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Die Arbeit stellt die Möglichkeiten von 3D-Controllern für den Einsatz in der interventionellen Radiologie und insbesondere für die Steuerung der Echtzeit-Magnetresonanztomographie (MRT) dar. Dies ist interessant in Bezug auf die kontrollierte Navigation in ein Zielgewebe. Dabei kann der Interventionalist durch Echtzeit- Bildgebung den Verlauf des Eingriffs verfolgen, allerdings kann er bisher das MRT während der Durchführung des Eingriffs nicht selbst steuern, da dies durch den Assistenten im Nebenraum erfolgt. Die Kommunikation ist bei dem hohen Geräuschpegel aber sehr schwer. Diese Arbeit setzt an dieser Stelle an und analysiert 3D-Controller auf die Eignung für die Echtzeit-Steuerung eines MRTs. Dabei wurden trackingbasierte und trackinglose Geräte betrachtet. Als Ergebnis ließ sich festhalten, dass trackingbasierte Verfahren weniger geeignet sind, aufgrund der nicht ausreichenden Interpretation der Eingaben. Die trackinglosen Geräte hingegen sind aufgrund der korrekten Interpretation aller Eingaben und der intuitiven Bedienung geeignet.
Social networks, smart portable devices, Internet of Things (IoT) on base of technologies like analytics for big data and cloud services are emerging to support flexible connected products and agile services as the new wave of digital transformation. Biological metaphors of living and adaptable ecosystems with service-oriented enterprise architectures provide the foundation for self-optimizing and resilient run-time environments for intelligent business services and related distributed information systems. We are extending Enterprise Architecture (EA) with mechanisms for flexible adaptation and evolution of information systems having distributed IoT and other micro-granular digital architecture to support next digitization products, services, and processes. Our aim is to support flexibility and agile transformation for both IT and business capabilities through adaptive digital enterprise architectures. The present research paper investigates additionally decision mechanisms in the context of multi-perspective explorations of enterprise services and Internet of Things architectures by extending original enterprise architecture reference models with state of art elements for architectural engineering and digitization.
The digital transformation of our society changes the way we live, work, learn, communicate, and collaborate. This disruptive change drive current and next information processes and systems that are important business enablers for the context of digitization since years. Our aim is to support flexibility and agile transformations for both business domains and related information technology with more flexible enterprise information systems through adaptation and evolution of digital architectures. The present research paper investigates the continuous bottom-up integration of micro-granular architectures for a huge amount of dynamically growing systems and services, like microservices and the Internet of Things, as part of a new composed digital architecture. To integrate micro-granular architecture models into living architectural model versions we are extending enterprise architecture reference models by state of art elements for agile architectural engineering to support digital products, services, and processes.
Digitization fosters the development of IT environments with many rather small structures, like Internet of Things (IoT), microservices, or mobility systems. They are needed to support flexible and agile digitized products and services. The goal is to create service-oriented enterprise architectures (EA) that are self optimizing and resilient. The present research paper investigates methods for decision-making concerning digitization architectures for Internet of Things and microservices. They are based on evolving enterprise architecture reference models and state of the art elements for architectural engineering for microgranular systems. Decision analytics in this field becomes increasingly complex and decision support, particularly for the development and evolution of sustainable enterprise architectures, is sorely needed. The challenging of the decision processes can be supported with in a more flexible and intuitive way by an architecture management cockpit.
Introducing continuous experimentation in large software-intensive product and service organisations
(2017)
Software development in highly dynamic environments imposes high risks to development organizations. One such risk is that the developed software may be of only little or no value to customers, wasting the invested development efforts.Continuous experiment ation, as an experiment-driven development approach, may reduce such development risks by iteratively testing product and service assumptions that are critical to the success of the software. Although several experiment-driven development approaches are available, there is little guidance available on how to introduce continuous experimentation into an organization. This article presents a multiple-case study that aims at better understanding the process of introducing continuous experimentation into an organization with an already established development process. The results from the study show that companies are open to adopting such an approach and learning throughout the introduction process. Several benefits were obtained, such as reduced development efforts, deeper customer insights, and better support for development decisions. Challenges included complex stakeholder structures, difficulties in defining success criteria, and building experimen- tation skills. Our findings indicate that organizational factors may limit the benefits of experimentation. Moreover, introducing continuous experimentation requires fundamental changes in how companies operate, and a systematic introduction process can increase the chances of a successful start.
Purpose: Human breath analysis is proposed with increasing frequency as a useful tool in clinical application. We performed this study to find the characteristic volatile organic compounds (VOCs) in the exhaled breath of patients with idiopathic pulmonary fibrosis (IPF) for discrimination from healthy subjects. Methods: VOCs in the exhaled breath of 40 IPF patients and 55 healthy controls were measured using a multi-capillary column and ion mobility spectrometer. The patients were examined by pulmonary function tests, blood gas analysis, and serum biomarkers of interstitial pneumonia. Results: We detected 85 VOC peaks in the exhaled breath of IPF patients and controls. IPF patients showed 5 significant VOC peaks; p-cymene, acetoin, isoprene, ethylbenzene, and an unknown compound. The VOC peak of p-cymene was significantly lower (p < 0.001), while the VOC peaks of acetoin, isoprene, ethylbenzene, and the unknown compound were significantly higher (p < 0.001 for all) compared with the peaks of controls. Comparing VOC peaks with clinical parameters, negative correlations with VC (r =−0.393, p = 0.013), %VC (r =−0.569, p < 0.001), FVC (r = −0.440, p = 0.004), %FVC (r =−0.539, p < 0.001), DLco (r =−0.394, p = 0.018), and %DLco (r =−0.413, p = 0.008) and a positive correlation with KL-6 (r = 0.432, p = 0.005) were found for p-cymene. Conclusion: We found characteristic 5 VOCs in the exhaled breath of IPF patients. Among them, the VOC peaks of p-cymene were related to the clinical parameters of IPF. These VOCs may be useful biomarkers of IPF.
The presented wide-Vin step-down converter introduces a parallel-resonant converter (PRC), comprising an integrated 5-bit capacitor array and a 300 nH resonant coil, placed in parallel to a conventional buck converter. Unlike conventional resonant concepts, the implemented soft-switching control eliminates input voltage dependent losses over a wide operating range. This ensures high efficiency across a wide range of Vin= 12-48V, 100-500mA load and 5V output at up to 15MHz switching frequency. The peak efficiency of the converter is 76.3 %. Thanks to the low output current ripple, the output capacitor can be as small as 50 nF, while the inductor tolerates a larger ESR, resulting in small component size. The proposed PRC architecture is also suitable for future power electronics applications using fast-switching GaN devices.
This publication gives a short introduction and overview of the European project SCOUT and introduces a methodology for a holistic approach to record the state of the art in technical (vehicle and connectivity, human factors regarding physiologic and ergonomic level) and non-technical enablers (societal, economic, legal, regulatory and policy level) of connected and automated driving in Europe. The paper addresses beside the technical topics of environmental perception, E/E architecture, actuators and security, the state of the art of the legal framework in the context of connected and automated driving.
Purpose: Medical processes can be modeled using different methods and notations.Currently used modeling systems like Business Process Model and Notation (BPMN) are not capable of describing the highly flexible and variable medical processes in sufficient detail.
Methods: We combined two modeling systems, Business Process Management (BPM) and Adaptive Case Management (ACM), to be able to model non-deterministic medical processes. We used the new Standards Case Management Model and Notation (CMMN) and Decision Management Notation (DMN).
Results: First, we explain how CMMN, DMN and BPMN could be used to model non-deterministic medical processes. We applied this methodology to model 79 cataract operations provided by University Hospital Leipzig, Germany, and four cataract operations provided by University Eye Hospital Tuebingen, Germany. Our model consists of 85 tasks and about 20 decisions in BPMN. We were able to expand the system with more complex situations that might appear during an intervention.
Conclusion: An effective modeling of the cataract intervention is possible using the combination of BPM and ACM. The combination gives the possibility to depict complex processes with complex decisions. This combination allows a significant advantage for modeling perioperative processes.
Nowadays CHP units are discussed for the production of electricity on demand rather than for generation of heat providing electricity as a by-product. By this means, CHP units are capable of satisfying a higher share of the electricity demand on-site and in this new role, CHP units are able to reduce the load on the power grid and to compensate for high fluctuations of solar and wind power.
Evidently, a novel control strategy for CHP units is required in order to shift the operation oriented at the heat demand to an operation led by the electricity demand. Nevertheless, the heat generated by the CHP unit needs to be utilized completely in any case, for maintaining energy as well as economic efficiency. Such a strategy has been developed at Reutlingen University, and it will be presented in the paper. Part of the strategy is an intelligent management for the thermal energy storage (TES) ensuring that the storage is at low level in terms of its heat content just before an electricity demand is calling the CHP unit into operation. Moreover, a proper forecast of both, heat and electricity demand, is incorporated and the requirements of the CHP unit in terms of maintenance and lifetime are considered by limiting the number of starts and stops per unit time and by maintaining a certain minimum length of the operation intervals.
All aspects of this novel control strategy are revealed in the paper, which has been implemented on a controller for further testing at two sites in the field. Results from these tests are given as well as results from a simulation model, which is able to evaluate the performance of the control strategy for an entire year.
This article covers the design of highly integrated gate drivers and level shifters for high-speed, high power efficiency and dv/dt robustness with focus on automotive applications. With the introduction of the 48 V board net in addition to the conventional 12 V battery, there is an increasing need for fast switching integrated gate drivers in the voltage range of 50 V and above. State-of-the-art drivers are able to switch 50 V in less than 5 ns. The high-voltage electrical drive train demands for galvanic isolated and highly integrated gate drivers. A gate driver with bidirectional signal transmission with a 1 MBit/s amplitude modulation, 10/20 MHz frequency modulation and power transfer over one single transformer will be discussed. The concept of high-voltage charge storing enables an area-efficient fully integrated bootstrapping supply with 70 % less area consumption. EMC is a major concern in automotive. Gate drivers with slope control optimize EMC while maintaining good switching efficiency. A current mode gate driver, which can change its drive current within 10 ns, results in 20 dBuV lower emissions between 7 and 60 MHz and 52 % lower switching loss compared to a conventional constant current gate driver.
A novel configuration of the dual active bridge (DAB) DC/DC converter is presented, enabling more efficient wide voltage range conversion at light loads. A third phase leg as well as a center tapped transformer are introduced to one side of the converter. This concept provides two different turn ratios, thus extending the zero voltage switching operation resulting in higher efficiency. A laboratory prototype was built converting an input voltage of 40V to an output voltage in the range of 350V to 650V. Measurements show a significant increase up to 20% in the efficiency for light-load operation.
This paper presents a control strategy for optimal utilization of photovoltaic (PV) generated power in conjunction with an Energy Storage System (ESS). The ESS is specifically designed to be retrofitted into existing PV systems in an end-user application. It can be attached in parallel to the PV system and connects to existing DC/AC inverters. In particular, the study covers the impact such a modification has on the output power of existing PV panels. A distinct degradation of PV output power was found due to the different power characteristics of PV panel and ESS. To overcome such degradation a novel feedback system is proposed. The feedback system continuously modifies the power characteristic of the ESS to match the PV panel and thus achieves optimal power utilization. Impact on PV and power point tracking performance is analyzed. Simulation of the proposed system is performed in MATLAB/Simulink. The results are found to be satisfactory.
How to protect the skin from getting sun burnt? The sun can damage your skin e.g. skin cancer. But the sun has a positive effect to the human. The time in sun and the intensity are key values between enjoy the sunbath and having a negative effect to the skin. A smart device like a UV flower could help you to enjoy the sunbath. It measures the UV index around you and gives this information to a smartphone app. The development steps of such a device are described in this paper. The UV flower is made of textile fabrics.
Afrika ist aufgrund überdurchschnittlicher Wirtschaftswachstumsraten und als die weltweit letzten unbearbeiteten Märkte seit einigen Jahren ein populäres Thema der Wirtschaft. Deutsche Unternehmen sind allerdings mit ihrem Engagement auf den afrikanischen Märkten sehr zurückhaltend. So schwankt der Anteil der deutschen Exporte nach Afrika an den deutschen Gesamtexporten seit zehn Jahren um die zwei Prozent; betrachtet man nur Subsahara‐Afrika, so waren es sogar nur 0,5 % in 2014 (Allafi und Koch 2015, S. 3). Bezüglich der Direktinvestitionen (nur Beteiligungskapital, ohne Direktinvestitionskredite) spielt Afrika eine noch geringere Rolle mit nur 1,5 % aller deutschen Investitionen in 2014, wobei hiervon so gut wie alle nach Nordafrika und Südafrika geflossen sind (Deutsche Bundesbank 2015, S. 12 f.). Neben den Standardgründen wie beispielsweise politischen Risiken, schlechter Infrastruktur, schwacher institutioneller Rahmenbedingungen und Governance‐Problemen (vgl. zum Beispiel World Bank 2016a), ist ein gängiges Markteintrittsproblem die fehlende Verfügbarkeit von lokalen Partnern in den Bereichen Vertrieb, Logistik und teilweise auch Produktion (vgl. zum Beispiel Carlowitz und Röndigs 2016). Aktuell ist ein Markteintritt in Afrika ohne lokalen Partner aufgrund der völlig anderen und schwierigen Rahmenbedingungen fast unmöglich.
In vitro composed vascularized adipose tissue is and will continue to be in great demand e.g. for the treatment of extensive high-graded burns or the replacement of tissue after tumor removal. Up to date, the lack of adequate culture conditions, mainly a culture medium, decelerates further achievements. In our study, we evaluated the influence of epidermal growth factor (EGF) and hydrocortisone (HC), often supplemented in endothelial cell (EC) specific media, on the co-culture of adipogenic differentiated adipose derived stem cells (ASCs) and microvascular endothelial cells (mvECs). In ASCs, EGF and HC are thought to inhibit adipogenic differentiation and have lipolytic activities. Our results showed that in indirect co-culture for 14 days, adipogenic differentiated ASCs further incorporated lipids and partly gained an univacuolar morphology when kept in media with low levels of EGF and HC. In media with high EGF and HC levels, cells did not incorporate further lipids, on the contrary, cells without lipid droplets appeared. Glycerol release, to measure lipolysis, also increased with elevated amounts of EGF and HC in the culture medium. Adipogenic differentiated ASCs were able to release leptin in all setups. MvECs were functional and expressed the cell specific markers, CD31 and von Willebrand factor (vWF), independent of the EGF and HC content as long as further EC specific factors were present. Taken together, our study demonstrates that adipogenic differentiated ASCs can be successfully co-cultured with mvECs in a culture medium containing low or no amounts of EGF and HC, as long as further endothelial cell and adipocyte specific factors are available.
IT Governance (ITG) is crucial due to its significant impact on enabling innovation and enhancing firm performance. Hence, in the last decade ITG has become important in both academic and in practical research. Although several studies have investigated individual aspects of ITG success and its impact on single determinants, the causal relationship of how ITG promotes firm performance remains unclear. Thus, a more comprehensive understanding about the link between ITG and firm performance is needed. To address this gap, this research aims at understanding how ITG and firm performance are related. Therefore, we conducted a systematic literature review (1) to create an overview on how current research structures the link between ITG mechanisms and firm performance, (2) to uncover key constructs as potential mediators or moderators on the general link between ITG and performance, and (3) to set the basis for future studies on the ITG-firm performance relationship.
The success of an autonomous robotic system is influenced by several interdependent factors not easily identifiable. This paper is set to lay the foundation of a new integrated approach in order to deeply examine all the parameters and understand their contribution to success. After introducing the problem, two cutting edge autonomous systems for the process of unloading of containers will be presented. Then the STIC analysis, a recently developed method for modelling and interpreting all the parameters, will be introduced. The preliminary results of applying such a methodology to a first study case, based on one of the two systems available to the authors, will be shortly presented. Future research is in the end recommended in order to prove that this methodology is the only way to efficiently and effectively mitigate the risk that stops potential users from investing in autonomous systems in the logistics sector.
Structural and functional thermosetting composite materials are exposed to different kinds of stress which can damage the polymer matrix, thus impairing the intended properties. Therefore, self-healing materials have attracted the attention of many research groups over the last decades in order to provide satisfactory material properties and outstanding product durability. The present article provides a critical overview of promising self-healing strategies for crosslinked thermoset polymers. It is organized in two parts: an overview about the different approaches to self-healing is given in the first part, whereas the second part focuses on the specific chemistries of the main strategies to achieve self-healing through crosslinking. It is attempted to provide a comprehensive discussion of different approaches which are described in the scientific literature. By comparison of the advantages and disadvantages, the authors wish to provide helpful insights on the assessment of the potential to transfer the extensive present knowledge about self-healing materials and methods to surface varnishing thermoset coatings.
In this work we investigate the behavior of MIS- and Schottky-gate AlGaN/GaN HEMTs under high-power pulsestress. A special setup capable of applying pulses of constant power is used to evaluate the electro-thermal response in different operating points. For both types of devices, the time to failure was found to decrease with increasing drain-source voltage. Overall, the Schottky-gate device displays a higher pulse robustness. The pulse withstand time of the MIS-gate device is limited by the occurrence of a thermal instability at approximately 240°C while the Schottky-gate device displays a rapid increase of the gate leakage current prior to failure. The mechanism responsible for this gate current is further investigated by static and transient temperature measurements and yielded activation energies of 0.6 eV and 0.84 eV.
The main challenge when driving heat pumps by PV-electricity is balancing differing electrical and thermal demands. In this article, a heuristic method for optimal operation of a heat pump driven by a maximum share of PV-electricity is presented. For this purpose, the (DHW) are activated in order shift the operation of the heat pump to times of PV-generation. The system under consideration refers to thermal and electrical demands of a single family house. It consists of a heat pump, a thermal energy storage for DHW and of grid connected heating and generation of domestic hot water, the heat pump runs with two different supply temperatures and thereby achieving a maximum overall COP. Within the algorithm for optimization a set of heuristic rules is developed in a way that the operational characteristics of the heat pump in terms of minimum running and stopping times are met as well as the limiting constraints of upper and lower limits of room temperature and energy content of electricity generated, a varying number of heat pump schedules fulfilling the bundary conditions are created. Finally, the schedule offering the maximum on-site utilization of PV-electricity with a minimum number of starts of the heat pump, which serves as secondary condition, is selected. Yearly simulations of this combination have been carried out. Initial results of this method indicate a significant rise in on-site consumption of the PV-electricity and heating demand fulfilment by renewable electricity with no need for a massive TES for the heating system in terms of a big water tank.
How to separate the wheat from the chaff: improved variable selection for new customer acquisition
(2017)
Steady customer losses create pressure for firms to acquire new accounts, a task that is both costly and risky. Lacking knowledge about their prospects, firms often use a large array of predictors obtained from list vendors, which in turn rapidly creates massive high-dimensional data problems. Selecting the appropriate variables and their functional relationships with acquisition probabilities is therefore a substantial challenge. This study proposes a Bayesian variable selection approach to optimally select targets for new customer acquisition. Data from an insurance company reveal that this approach outperforms nonselection methods and selection methods based on expert judgment as well as benchmarks based on principal component analysis and bootstrap aggregation of classification trees. Notably, the optimal results show that the Bayesian approach selects panel-based metrics as predictors, detects several nonlinear relationships, selects very large numbers of addresses, and generates profits. In a series of post hoc analyses, the authors consider prospects’ response behaviors and cross selling potential and systematically vary the number of predictors and the estimated profit per response. The results reveal that more predictors and higher response rates do not necessarily lead to higher profits.
This article provides a general overview of the most promising candidates of bio based materials and deals with the most important issues when it comes to their incorporation into PF resins. Due to their abundance on Earth, much knowledge of lignin-based materials has already been gained and uses of lignin in PF resins have been studied for many decades. Other natural polyphenols that are less frequently considered for impregnation are covered as well, as they do also possess some potential for PF substitution.
High quality decorative laminate panels typically consist of two major types of components: the surface layers comprising décor and overlay papers that are impregnated with melamine-based resins, and the core which is made of stacks of kraft papers impregnated with phenolic (PF) resin. The PF-impregnated layers impart superior hydrolytic stability, mechanical strength and fire-resistance to the composite. The manufacturing involves the complex interplay between resin, paper and impregnation/drying processes. Changes in the input variables cause significant alterations in the process characteristics and adaptations of the used materials and specific process conditions may, in turn, be required. This review summarizes the main variables influencing both processability and technological properties of phenolic resin impregnated papers and laminates produced therefrom. It is aimed at presenting the main influences from the involved components (resin and paper), how these may be controlled during the respective process steps (resin preparation and paper production), how they influence the impregnation and lamination conditions, how they affect specific aspects of paper and laminate performance, and how they interact with each other
(synergies).
Characterisation of porous knitted titanium for replacement of intervertebral disc nucleus pulposus
(2017)
Effective restoration of human intervertebral disc degeneration is challenged by numerous limitations of the currently available spinal fusion and arthroplasty treatment strategies. Consequently, use of artificial biomaterial implant is gaining attention as a potential therapeutic strategy. Our study is aimed at investigating and characterizing a novel knitted titanium (Ti6Al4V) implant for the replacement of nucleus pulposus to treat early stages of chronic intervertebral disc degeneration. Specific knitted geometry of the scaffold with a porosity of 67.67 ± 0.824% was used to overcome tissue integration failures. Furthermore, to improve the wear resistance without impairing original mechanical strength, electro-polishing step was employed. Electro-polishing treatment changed a surface roughness from 15.22 ± 3.28 to 4.35 ± 0.87 μm without affecting its wettability which remained at 81.03 ± 8.5°. Subsequently, cellular responses of human mesenchymal stem cells (SCP1 cell line) and human primary chondrocytes were investigated which showed positive responses in terms of adherence and viability. Surface wettability was further enhanced to super hydrophilic nature by oxygen plasma treatment, which eventually caused substantial increase in the proliferation of SCP1 cells and primary chondrocytes. Our study implies that owing to scaffolds physicochemical and biocompatible properties, it could improve the clinical performance of nucleus pulposus replacement.
This paper reports an analysis of application and impact of FMEA on susceptibility of generic IT-networks. It is not new that in communication system, the frequency and the data transmission rate play a very important role. The rapid increase in miniaturization of electronic devices leads to very sensitivity against electromagnetic interference. Since the IT network with the data transfer rate makes a huge contribution to this development it is very important to monitor their functionality. Therefore, tests are performed to observe and ensure the data transfer rate of IT networks against IEMI. A fault tree model is presented and observed effects during radiation of disturbance on complex system by a HPEM interference sources are described using a continuous and consistent model of the physical layer to the application layer.
This work presents a spiral antenna array, which can be used in the V- and W-Band. An array equipped with Dolph-Chebychev coefficients is investigated to address issues related to the low gain and side lobe level of the radiating structure. The challenges encountered in this achievement are to provide an antenna that is not only good matched but also presents an appreciable effective bandwidth at the frequency bands of interest. Its radiation properties including the effective bandwidth and the gain are analyzed for the W-Band.
Electric freight vehicles have the potential to mitigate local urban road freight transport emissions, but their numbers are still insignificant. Logistics companies often consider electric vehicles as too costly compared to vehicles powered by combustion engines. Research within the body of the current literature suggests that increasing the driven mileage can enhance the competitiveness of electric freight vehicles. In this paper we develop a numeric simulation approach to analyze the cost-optimal balance between a high utilization of medium-duty electric vehicles – which often have low operational costs – and the common requirement that their batteries will need expensive replacements. Our work relies on empirical findings of the real-world energy consumption from a large German field test with medium-duty electric vehicles. Our results suggest that increasing the range to the technical maximum by intermediate (quick) charging and multi-shift usage is not the most cost-efficient strategy in every case. A low daily mileage is more cost-efficient at high energy prices or consumptions, relative to diesel prices or consumptions, or if the battery is not safeguarded by a long warranty. In practical applications our model may help companies to choose the most suitable electric vehicle for the application purpose or the optimal trip length from a given set of options. For policymakers, our analysis provides insights on the relevant parameters that may either reduce the cost gap at lower daily mileages, or increase the utilization of medium-duty electric vehicles, in order to abate the negative impact of urban road freight transport on the environment.
In this study, a novel strategy has been developed for the assembly of polyelectrolyte multilayer (PEM) on CaCO3 templates in acidic pH solutions, where consecutive polyelectrolyte layers (heparin/poly(allylamine hydrochloride) or heparin/chitosan) were deposited on PEM hollow microcapsules established previously on CaCO3 templates. The PEM build-up, hollow capsule characterization and successful encapsulation of fluorescein 5(6)-isothiocyanate (FITC)-Dextran by coprecipitation with CaCO3 are demonstrated. Improvement by the removal of CaCO3 core was achieved while the depositions. In the course of the release profile, high retardation for encapsulated FITC-Dextran was observed. The combined shell capsules system is a significant trait that has potential use in tailoring functional layer-by-layer capsules as intelligent drug delivery vehicles where the preliminary in vitro tests showed the responsiveness on the enzymes.
The purpose of this paper is to identify the potential of a fashion fTRACE (ffTRACE) application that gives transparent insight on the supply chain of a fashion item. The research methodology applied to this purpose is a literature review examining academic references. The key findings of this paper are that information plays a major role in the consumer decision process and is therefore beneficial to the demand for sustainable products. Given the right information content in a transparent, credible and understandable way is important. It is found that the functions of such an application would be able to satisfy this consumer demand and therefore has the potential to raise the sales of a sustainable company as well as increase the brand’s awareness and improve its image. While mainly indicating the potentials of the ffTRACE application, their relevance is not examined in this paper.
The purpose of this paper is to investigate the use of sustainable closed-loop supply chain of the fashion brand Filippa K. Information on green fashion has been gathered and a case study approach on the fashion retailer
Filippa K conducted. Results show a switch in knowledge content between a fast fashion supply chain and a sustainable supply chain. Also there is an evolution in sustainability as companies, retailers, and manufactures suffer under pressure from the customers, governments, and the media. Sustainable fashion brands like Filippa K are interested in sharing precise knowledge on variety of aspects linked to the sustainable closed-loop supply chain. This research paper has been limited by less information and unexplored topics in the theme green fashion. This led to the personal critical disputation with the brand Filippa K.
The purpose of this paper is to investigate how the practice of closed-loop production systems (CLPS) is implemented in the fashion industry. This paper offers a critical literature review to present a thorough understanding of the actual status of literature. Subsequently, the paper reveals that CLPS are of great importance. Generally, such systems include different activities that have to be integrated. Critical points are the product acquisition, the recovering process itself and the remarketing to the customer. A lack of reliable data concerning CLPS in the specific case of fashion industry can be identified. Important research fields could be marketing strategies, controlling the acquisition process, evolvement of return technologies and strategies, adaption of recovered products to the mass market, and the development of new technologies concerning recovering processes.
The purpose of this paper is to explain the key aspects and growing relevance of sustainability in fashion retail and to evaluate the possibilities of fashion retailers to act sustainable in supply chain management as well as carving out the challenges they have to deal with. The research methodology applied for this purpose is a critical literature review examining books and articles. The findings demonstrate the rising importance of sustainability in fashion retail. In this regard, fashion retailers play a key role and responsibility for sustainability in the fashion supply chain, from the beginning up to the end. This paper mainly analyzes sustainability in the fashion supply chain. It does not analyze topics like second-hand shopping or social media sustainability.
Since there is no denying that transparency is increasingly central to corporate sustainability, the purpose of this paper is a case study on a company’s attempt to be fully transparent, hence, picking up the existent scholarly conversation about uncompromising supply chain transparency. Literature so far was found to be fairly limited, but, following a trend, has been rising in numbers over recent years. Addressing these shortcomings in the methodology, an in-depth literature review about the multiple dimensions of supply chain transparency has been performed and links within supply networks stressed. On this basis, a case study by exemplary illustrating the fashion label Honestby has been drafted and the effort to become the world’s first 100 % transparent company further examined. Findings are discussed whether more supply chain transparency is desirable in any case, obstacles listed and an outlook for this kind of business model has been drawn. The research is clearly limited by the amount of scholarly literature concerning Honestby in particular. Out of this reason, magazines and journal entries are used as reference as well. Only with the extension of the topic itself to supply chain transparency and the literature review beforehand, the paper gained its necessary academic standard. Concerning implications, it needs to be mentioned that even though Honest by demonstrates to be fully transparent, it was not possible to find any public information about the degree of supplier relationship. In particular, concerning the applied control mechanisms used to exert influence and to balance out the power gradient between company and suppliers.
The purpose of this paper is to study the recycling form of reusing second hand clothing from a conventional fashion brand’s perspective. It should clarify which measures and activities a fashion company needs to integrate in its value chain in order to offer branded second hand merchandise in a self-operated store. The research paper relies on a desk-based research and aims to illustrate the topic by means of a descriptive approach, processing the existing literature. Key findings demonstrate that fashion brands need to integrate complete lifecycle strategies, sustainability communication, and reverse logistics structures, like take-back schemes, for offering second hand clothing. The main limitations evolve from the research design. Further, empirical evidences need to be conducted for a more fundamental understanding of the new business model.
The purpose of this paper is to define what impacts sustainable manufacturing standards have for retail brands concerning the communication policy and to find possible solutions of how the companies can deal with them. Therefore, sustainable standards and the impacts on the internal and external communication are described. The enclosed discussion finds possible solutions for the negative impacts. A literature discussion has been conducted to investigate the purpose. Generally, there are many impacts fashion retails have to consider, if they want to transform their company to become more sustainable, because only the impacts on a defined part of the communication policy were huge. A limitation of this paper is that the proposals how retailers could deal with the impacts of the transformation of the company toward more sustainability need further research and tests until they are practicable.
The second hand concept indicates a growing trend in clothing recently, leading to growing numbers of second hand shops and developments of new second hand retail forms. This paper concentrates on the current second hand market for fashion products and presents the different motives toward second hand consumption as well as alternative consumption channels for second hand products. The findings of the paper are founded on literature research of academic articles and case studies. Results show that there is a high potential for the second hand market due to the increasing interest of consumers in buying second hand products. The paper concentrates on the second hand market for fashion products in the western society. This means that there was no research on second hand products for disadvantaged people in poor countries. Furthermore, the paper focuses the formal second hand retail channels to see what is already on the market.
The purpose of this research is to explore current boundaries of the fashion industry’s second hand market and which solutions and approaches can be adopted from the used-car industry. The paper is based on the study of existing literature which deals with sustainability in combination with second hand markets in general and adaptable features of the used-car industry. Adaptable features are found using the business model canvas. The key finding of this study indicates that the fashion industry faces immense social and environmental challenges which can be partly solved by the development of the second hand market. Used-car industry can be seen as role model for fashion retail. In this study only aspects of used-car distribution are highlighted; therefore, characteristics of the recycling of used cars are not examined.
The purpose of this paper is to examine the impact on sustainability of fashion production and consumption in order to discuss what the main lever is to reduce the negative impact. The research methodology applied is a literature review examining academic references. Key findings suggest that fashion production and consumption have a single comparable impact on sustainability. Moreover, as the fashion production follows the demand, the consumer steers the production in a certain direction. Therefore, consumers take over responsibility and need to be informed. To reach a long-term change in the fashion industry, the consumer has to be the focus of the sustainable efforts. Most results in literature were conducted by qualitative research methods, so that further quantitative testing of the results is recommended. Furthermore, most surveys were conducted with young fashion consumers in the EU or UK which does not represent the fashion consumer in general.
The purpose of this paper is to highlight potentials and limitations of the prosumer concept in fashion retail. The paper illustrates the evolution of prosumption and in which directions the concept is being developed. The primary research is based on a literature review containing different sources of academic and non-academic references. Findings suggest that the prosumer concept is no new phenomenon. Recently, it has moved into the focus of companies that have noted that it is efficient when engaging with customers in order to strengthen their brand loyalty. An increasing number of companies offer innovative business models that underlie the concept. However, lately smart prosuming machines are changing the objectives of the concept. Even if the prosumer concept exists since many years and scholars investigate its potentials continuously, it is the fashion industry that has been researched comparatively little up to now.
This study focuses on the different roles of social media for the promotion of a sustainable lifestyle, behaviour and consumption, especially with regard to the typically non-ethical fashion industry. Research findings include eight roles of social media influencing a sustainable consumption contrary to prior research naming one to five impacts. Results show that social media educates and engages the young and ethically interested target group besides increasing supply chain transparency and brand or theme awareness. Furthermore, social media provides a platform for organisations’ relationship management and social interaction since users get empowered to share experiences which leads to a higher level of trust.
The purpose of this paper is to evaluate consisting consumption patterns caused by fast fashion with a new appearing form of consumption and retaining potentials as an alternative as well as sustainable form of fast fashion consumption. This research is set up on a theoretical background of scientific literature including governmental as well as press releases in order to evaluate the status quo of consumption and answering the research question. A new consumption pattern as well as an appearing economy of sharing can be stated including potential aspects of raising businesses and sustainable alternative forms of fast fashion. The framework of the research is limited to the textile and fashion industry in industrialized countries focusing on consumption in the twenty first century.
Die Arbeit stellt die Vision des Internet of Things (IoT) vor und betrachtet sowohl Möglichkeiten der Nutzung als auch Gefahrenpotentiale für die Sicherheit der Nutzer. Insbesondere wird hierbei der Anwendungsfall Smart Home näher betrachtet und am Beispiel ZigBee gravierende Schwächen dieser Geräte aufgezeigt.
The wet chemical deposition of solution processed transparent conducting oxides (TCO) provides an alternative low cost and economical deposition technique to realize large-areas of conducting films. Since the price for the most common TCO Indium Tin Oxide rises enormously, Aluminum Zinc Oxide (AZO) as alternative TCO reaches more and more interest. The optoelectronical properties of nanoparticle coatings strongly depend beneath the porosity of the coating on the shape and size of the used particles. By using bigger or rod-shaped particles it is possible to minimize the amount of grain boundaries resulting in an improvement of the electrical properties, whereas particles bigger than 100 nm should not be used if highly transparent coatings are necessary as these big particles scatter the visible light and lower the transmittance of the coatings. In this work we present a simple method to synthesize AZO particles with different shape and size, but comparable electronical properties. We use a simple, well reproducible polyol method for synthesis and influence the shape and size of the particles by adding different amounts of water to the precursor solution. We can show that the addition of aluminum as dopant strongly hinders the crystal growth but the addition of water counteracts this, so that both, spherical and rod-shaped particles can be obtained.
In recent times, enterprises have been increasingly dealing with the use of social media in internal communication and collaboration. In particular, so-called Enterprise Social Networks (ESN) promise meaningful benefits for the nature of work in corporations. However, these platforms often suffer from poor degrees of use. This raises the question of what initiatives enterprise can launch in order to stimulate the vitality of ESN. Since the use of ESN is often voluntary, individual adoption by employees need to be examined to find an answer. Therefore, the Unified Theory of Acceptance and Use of Technology (UTAUT) model was selected for the theoretical foundation of this paper. Following a qualitative research approach, the available research provides an analysis of expert interviews on specific ESN implementation strategies and included factors. In order to extensively conceptualize and generalize these strategic considerations, we conducted an inductive coding process. The results reveal that ESN implementation strategies can be understood as a multi-level construct (individual vs. group vs. organizational level) containing different factors dependent on the degree of documentation and intensity. This research in progress describes a qualitative evaluation as a preliminary study for further quantitative analysis of an ESN adoption model.
Medical applications are becoming increasingly important in the current development of health care and therefore a crucial part of the medical industry. The work focuses on the analysis of requirements and the challenges arisen from designing mobile medical applications in relation to the user interface. The paper describes the current status in the development of mobile medical apps and illustrates the development of e-health market. The author will explain the requirements and will illustrate the hurdles and problems. He refers to the German market which is similar to the European and compares that with the market in the USA.
Medical applications are becoming increasingly important in the current development of health care and therefore a crucial part of the medical industry. An essential component is the development of user interfaces for mobile medical applications. The conceptual process is crucial for the further development of the main development process. Inconsistency or errors in the conceptual phase, have a serious impact on all areas and could prevent the certification for market approval.
This paper presents a guide to support developer with this process. It was developed based on a requirement analysis of the legal requirements to publish a medical device.
More and more power electronics applications utilize GaN transistors as they enable higher switching frequencies in comparison to conventional Si devices. Faster switching shrinks down the size of passives and enables compact solutions in applications like renewable energy, electrical cars and home appliances. GaN transistors benefit from ~10× smaller gate charge QG and gate drive voltages in the range of typically 5V vs. ~15V for Si.
This work presents a fully integrated GaN gate driver in a 180nm HV BCD technology that utilizes high-voltage energy storing (HVES) in an on-chip resonant LC tank, without the need of any external capacitor. It delivers up to 11nC gate charge at a 5V GaN gate, which exceeds prior art by a factor of 45-83, supporting a broad range of GaN transistor types. The stacked LC tank covers an area of only 1.44mm², which corresponds to a superior value of 7.6nC/mm².
New digital technologies present both game-changing opportunities for—and existential threats to—companies whose success was built in the pre-digital economy. This article describes our findings from a study of 25 companies that were embarking on digital transformation journeys. We identified two digital strategies—customer engagement and digitized solutions—that provide direction for a digital transformation. Two technology-enabled assets are essential for executing those strategies: an operational backbone and a digital services platform. We describe how a big old company can combine these elements to navigate its digital transformation.
In any autonomous driving system, the map for localization plays a vital part that is often underestimated. The map describes the world around the vehicle outside of the sensor view and is a main input into the decision making process in highly complicated scenarios. Thus there are strict requirements towards the accuracy and timeliness of the map. We present a robust and reliable approach towards crowd based mapping using a GraphSLAM framework based on radar sensors. We show on a parking lot that even in dynamically changing environments, the localization results are very accurate and reliable even in unexplored terrain without any map data. This can be achieved by collaborative map updates from multiple vehicles. To show these claims experimentally, the Joint Graph Optimization is compared to the ground truth on an industrial parking space. Mapping performance is evaluated using a dense map from a total station as reference and localization results are compared with a deeply coupled DGPS/INS system.
Decreasing batch sizes in production in line with Industrie 4.0 will lead to tremendous changes of the control of logistic processes in future production systems. Intelligent bins are crucial enablers to establish decentrally controlled material flow systems in value chain networks as well as at the intralogistics level. These intelligent bins have to be integrated into an overall decentralized monitoring and control approach and have to interact with humans and other entities just like other cyber-physical systems (CPS) within the cyber-physical production system (CPPS). To realize a decentralized material supply following the overall aim of a decentralized control of all production and logistics processes, an intelligent bin system is currently developed at the ESB Logistics Learning Factory. This intelligent bin system will be integrated into the self developed, cloud-based and event-oriented SES system (so-called “Self Execution System”) which goes beyond the common functionalities and capabilities of traditional manufacturing execution systems (MES).
To ensure a holistic integration of the intelligent bin for different material types into the SES framework, the required hard- and software components for the decentrally controlled bin system will be split into a common and an adaptable component. The common component represents the localization and network layer which is common for every bin, whereas the flexible component will be customizable to different requirements, like to the specific characteristics of the parts.
This paper presents a novel multi-modal CNN architecture that exploits complementary input cues in addition to sole color information. The joint model implements a mid-level fusion that allows the network to exploit cross modal interdependencies already on a medium feature-level. The benefit of the presented architecture is shown for the RGB-D image understanding task. So far, state-of-the-art RGB-D CNNs have used network weights trained on color data. In contrast, a superior initialization scheme is proposed to pre-train the depth branch of the multi-modal CNN independently. In an end-to-end training the network parameters are optimized jointly using the challenging Cityscapes dataset. In thorough experiments, the effectiveness of the proposed model is shown. Both, the RGB GoogLeNet and further RGB-D baselines are outperformed with a significant margin on two different tasks: semantic segmentation and object detection. For the latter, this paper shows how to extract object level groundtruth from the instance level annotations in Cityscapes in order to train a powerful object detector.
Diese Arbeit beschäftigt sich mit dem neuen elektronischen Personalausweis. Zum einen werden in diesem Paper die Sicherheitsziele des Personalausweises und die technische Umsetzung der Architektur und Protokolle erklärt. Es wird der Ablauf einer Online-Identifizierung für einen Nutzer mithilfe des Ausweises aufgezeigt. Risiken und Schwachstellen der Technologie im Software- und Hardwarebereich werden diskutiert und die bereits erfolgten Hack-Angriffe aufgezeigt. Die Arbeit legt Möglichkeiten dar, wie sich der Nutzer vor Angriffen schützen kann. Es werden die Gründe genannt, warum der neue Personalausweis online nur schwar Anklang findet und warum die Aufklärung über die zur Verfügung stehenden Anwendungen, eine Preisreduzierung der Lesegeräte sowie die vom Europa-Parlament und Europarat erlassene eIDAS-Verordnung nicht helfen werden, um die Nutzung voranzutreiben. Ergebnisse hierfür liefert eine Nutzerstudie. Zum anderen werden Ideen genannt, wie die Nutzung der elektronischen Funktionen des Ausweises stattdessen zu fördern ist.
Electronic word-of-mouth (eWoM) communication plays an increasingly important role in modern business. The underlying concept of word-of-mouth (WoM) communication is well researched and has proved highly significant in respect of its impact on customers purchase behavior. However, due to the advent of digital technologies, decision-making among customers is progressively shifting to the online world. Consequently, eWoM has received a lot of attention from the academic community. As multiple research papers focus on specific facets of eWoM, there is a need to integrate current research results systematically. Thus, this paper presents a scientific literature analysis in order to determine the current state-of-the-art in the field of eWoM. Five main research areas were analyzed, supporting the need for further eWoM studies and providing a structured overview of existing results.
Trotz größer werdendem Tenor, die Intuition als gewinnbringende Ergänzung zur rational geprägten Entscheidungskultur im Vertrieb zu implementieren, scheint dennoch Unsicherheit und Unwissenheit über den richtigen Umgang mit der Intuition seitens der Mitarbeiter und Mitarbeiterinnen vorzuherrschen. Durch die systematische Legitimierung der Intuition Vertrieb kann diesem Umstand entgegengewirkt werden.
In the lights of an increasing digitalization of companies, the sales process might experience changes in the usage and the influence of digital tools. In order to examine the status quo of German companies in this regard, a study was conducted between 235 participants. The results of this study will be outlined in the article at hand.
Digitization will require companies to fundamentally reengineer their sales processes. Adapting the concept of value selling to the digital age will enable them to deliver superior value to their customers. Specifically, social selling will provide them with an answer to the ever-increasing complexity of customer journeys. This article, based on a survey among 235 German companies, assesses the status quo and outlines opportunities. Moreover, it introduces a novel approach for developing well-grounded social selling metrics.
Der B-to-B-Vertrieb hat sich durch neueste Informationstechnologien stark verändert und ist wesentlich komplexer geworden. Gleichwohl haben sich die Möglichkeiten dadurch auch dramatisch verbessert. International agierende, virtuell zusammenarbeitende Teams haben die Entscheidungsprozesse und Kompetenzen verschoben. Mit Social Selling bietet sich jetzt eine Möglichkeit, die neu entstandenen Herausforderungen im Vertrieb besser zu meistern.
Der folgende Artikel befasst sich mit Wearables für Pferde. Ziel ist es, die Sicherheit der Tiere bei einem Ausbruch von einer Weide zu erhöhen und damit Personen- und Sachschäden zu minimieren. Hierzu wird der Stand der Technik zur Standortbestimmung im Freien zusammengetragen und durch eine Klassifizierung der unterschiedlichen Ansätze ermittelt, welche Standortbestimmung pferdegerecht erscheint. Zudem soll ein Fragebogen konzipiert werden, um Charakteristiken und Funktionalitäten für einen Prototypen festzustellen.
Digitization transforms business process models and processes in many enterprises. However, many of them need guidance, how digitization is impacting the design of their information systems. Therefore, this paper investigates the influence of digitization on information system design. We apply a two-phase research method applying a literature review and an exploratory case study. The case study took place in the IT service provider of a large insurance enterprise. The study’s results suggest that a number of areas of information system design are affected, such as architecture, processes, data and services.
Modern power transistors are able to switch at very high transition speed, which can cause EMC violations and overshoot. This is addressed by a gate driver with variable gate current, which is able to control the transition speed. The key idea is that the gate driver can influence the di/dt and dv/dt transition separately and optimize whichever transition promises the highest improvement while keeping switching losses low. To account for changes in the load current, supply voltage, etc., a control loop is required in the driver to ensure optimized switching. In this paper, an efficient control scheme for an automotive gate driver with variable output current capability is presented. The effectiveness of the control loop is demonstrated for a MOSFET bridge consisting of OptiMOS-T2™devices with a total gate charge of 39nC. This bridge setup shows dv/dt transitions between 50 to 1000ns, depending on driving current. The driver is able to switch between gate current levels of 1 to 500mA in 10/15ns (rising/falling transition). With the implemented control loop the driver is measured to significantly reduce the ringing and thereby reduce device stress and electromagnetic emissions while keeping switching losses 52% lower than with a constant current driver.
Es wird gezeigt, wie bei Fernspeisung die Vorhersage der Erwärmung mit entsprechender Modellierung verbessert werden kann und wie der Einfluss von Material und Form des Kabelkanals die Erwärmung und das das Temperaturprofil des Bündels beeinflusst. Es wird auch vorgestellt, dass die erhöhte Erwärmung von Metallkabelkanälen auf die geringere Emissivität zurückzuführen ist und wie das verbessert werden kann.
To evaluate the quality of sleep, it is important to determine how much time was spent in each sleep stage during the night. The gold standard in this domain is an overnight polysomnography (PSG). But the recording of the necessary electrophysiological signals is extensive and complex and the environment of the sleep laboratory, which is unfamiliar to the patient, might lead to distorted results. In this paper, a sleep stage detection algorithm is proposed that uses only the heart rate signal, derived from electrocardiogram (ECG), as a discriminator. This would make it possible for sleep analysis to be performed at home, saving a lot of effort and money. From the heart rate, using the fast Fourier transformation (FFT), three parameters were calculated in order to distinguish between the different sleep stages. ECG data along with a hypnogram scored by professionals was used from Physionet database, making it easy to compare the results. With an agreement rate of 41.3%, this approach is a good foundation for future research.
A wide variety of cell types exhibit substrate topography-based behavior, also known as contact guidance. However, the precise cellular mechanisms underlying this process are still unknown. In this study, we investigated contact guidance by studying the reaction of human endothelial cells (ECs) to well-defined microgroove topographies, both during and after initial cell spreading. As the cytoskeleton plays a major role in cellular adaptation to topographical features, two methods were used to perturb cytoskeletal structures. Inhibition of actomyosin contractility with the chemical inhibitor blebbistatatin demonstrated that initial contact guidance events are independent of traction force generation. However, cell alignment to the grooved substrate was altered at later time points, suggesting an initial ‘passive’ phase of contact guidance, followed by a contractility-dependent ‘active’ phase that relies on mechanosensitive feedback. The actin cytoskeleton was also perturbed in an indirect manner by culturing cells upside down, resulting in decreased levels of contact guidance and suggesting that a possible loss of contact between the actin cytoskeleton and the substrate could lead to cytoskeleton impairment. The process of contact guidance at the microscale was found to be primarily lamellipodia driven, as no bias in filopodia extension was observed on micron-scale grooves.
Recent digital technologies like the Internet of Things and Augmented Reality have brought IT into companies’ core products. What were previously purely physical products are becoming hybrid or digitized. Despite receiving a lot of recent attention, digitized products have only seen a slow uptake in businesses so far. In this paper, we study the challenges that keep companies from realizing the desired impacts of digitized products and the practices they employ to address these challenges. To do so, we looked at companies from a set of industries that are highly affected by digital transformation, but at the same time hesitant to move to a more digitized world: the creative industries. Based on a literature review and twelve interviews in creative industries, we developed a conceptual model that can serve as a basis for formulating testable hypotheses for further research in this area.
In vitro cultured cells produce a complex extracellular matrix (ECM) that remains intact after decellularization. The biological complexity derived from the variety of distinct ECM molecules makes these matrices ideal candidates for biomaterials. Biomaterials with the ability to guide cell function are a topic of high interest in biomaterial development. However, these matrices lack specific addressable functional groups, which are often required for their use as a biomaterial. Due to the biological complexity of the cell-derived ECM, it is a challenge to incorporate such functional groups without affecting the integrity of the biomolecules within the ECM. The azide-alkyne cycloaddition (click reaction, Huisgen-reaction) is an efficient and specific ligation reaction that is known to be biocompatible when strained alkynes are used to avoid the use of copper (I) as a catalyst. In our work, the ubiquitous modification of a fibroblast cell-derived ECM with azides was achieved through metabolic oligosaccharide engineering by adding the azide-modified monosaccharide Ac4GalNAz (1,3,4,6 tetra-O-acetyl-N-azidoacetylgalactosamine) to the cell culture medium. The resulting azide-modified network remained intact after removing the cells by lysis and the molecular structure of the ECM proteins was unimpaired after a gentle homogenization process. The biological composition was characterized in order to show that the functionalization does not impair the complexity and integrity of the ECM. The azides within this ‘‘clickECM” could be accessed by small molecules (such as an alkyne modified fluorophore) or by surface-bound cyclooctynes to achieve a covalent coating with clickECM.
Das Ziel dieser Arbeit ist, die Infrastruktur einer modernen Fahrzeug-zu Fahrzeug-Kommunikation auf ihre Sicherheit zu prüfen. Dazu werden die Sicherheitsstandards für die Funkkommunikation genauer beschrieben und anschließend mit möglichen Angriffsmodellen geprüft. Mit dem erläuterten Wissen der VANET Architektur werden verschiedene Angriffe verständlicher. Dadurch werden die Schwachstellen offengelegt und Gegenmaßnahmen an passenden Punkten in der Architektur verdeutlicht.
This paper examines the efficacy of social media systems in customer complaint handling. The emergence of social media, as a useful complement and (possibly) a viable alternative to the traditional channels of service delivery, motivates this research. The theoretical framework, developed from literature on social media and complaint handling, is tested against data collected from two different channels (hotline and social media) of a German telecommunication services provider, in order to gain insights into channel efficacy in complaint handling. We contribute to the understanding of firm’s technology usage for complaint handling in two ways:
(a) by conceptualizing and evaluating complaint handling quality across traditional and social media channels and (b) by comparing the impact of complaint handling quality on key performance outcomes such as customer loyalty, positive word-of-mouth, and crosspurchase intentions across traditional and social media channels.
Electronic word-of-mouth (eWoM) communication has received a lot of attention from the academic community. As multiple research papers focus on specific facets of eWoM, there is a need to integrate current research results systematically. Thus, this paper presents a scientific literature analysis in order to determine the current state-of-the-art in the field of eWoM.
This paper investigates the impact of dynamic capabilities (DC) on brand love. From a resource-based view, there is little clarity vis-à-vis the specific capabilities that drive the ability to create brand love. This paper focuses on three research questions: Firstly, which dynamic capabilities are relevant for brand love? Secondly, how strong is the impact of certain dynamic capabilities on brand love? Thirdly, which conditions mediate and moderate the impact of specific dynamic capabilities on brand love? Data from a multi-method research approach have been used to itentify the specific capabilities that corporations need, to enhance brand love. Furthermore, a standardized online survey was conducted on marketing executives and evaluated by structural equation modeling. The results indicate, that customer expertise plays a major role in the relationship between dynamic capabilities and brand love. Furthermore, this relationship is more important in markets that have a low competitive differentiation in products and services.
We were able to identify a set of specific capabilities corporations need to develop in order to enhance brand love. Furthermore, the effects of most dynamic capabilities on brand love have a strong correlation to the degree of customer orientation. Other results are relevant concerning the proposed moderation and mediation hypotheses. Firstly, the impact of customer orientation on brand love is varied under specific market conditions, supporting our central moderation hypothesis (β = .259, p = .001). To be precise, the impact of customer orientation is strongest in markets that have low competitive differentiation in products and services. Other control variables like age, gender, or market form (B2B versus B2C) lead to no significant heterogeneity in the data set. Finally, mediation analyses show no significant “direct effect” of the existing DC constructs on brand love, supporting the mediating role of customer orientation.
LDMOS transistors in integrated power technologies are often subject to thermo-mechanical stress, which degrades the on-chip metallization and eventually leads to a short. This paper investigates small sense lines embedded in the LDMOS metallization. It will be shown that their resistance depends strongly on the stress cycle number. Thus, they can be used as aging sensors and predict impending failures. Different test structures have been investigated to identify promising layout configurations. Such sensors are key components for resilient systems that adaptively reduce stress to allow aggressive LDMOS scaling without increasing the risk of failure.
Characteristics of modern computing and storage technologies fundamentally differ from traditional hardware. There is a need to optimally leverage their performance, endurance and energy consumption characteristics. Therefore, existing architectures and algorithms in modern high performance database management systems have to be redesigned and advanced. Multi Version Concurrency Control (MVCC) approaches in data-base management systems maintain multiple physically independent tuple versions. Snapshot isolation approaches enable high parallelism and concurrency in workloads with almost serializable consistency level. Modern hardware technologies benefit from multi-version approaches. Indexing multi-version data on modern hardware is still an open research area. In this paper, we provide a survey of popular multi-version indexing approaches and an extended scope of high performance single-version approaches. An optimal multi-version index structure brings look-up efficiency of tuple versions, which are visible to transactions, and effort on index maintenance in balance for different workloads on modern hardware technologies.
Database management systems (DBMS) are critical performance components in large scale applications under modern update intensive workloads. Additional access paths accelerate look-up performance in DBMS for frequently queried attributes, but the required maintenance slows down update performance. The ubiquitous B+ tree is a commonly used key-indexed access path that is able to support many required functionalities with logarithmic access time to requested records. Modern processing and storage technologies and their characteristics require reconsideration of matured indexing approaches for today's workloads. Partitioned B-trees (PBT) leverage characteristics of modern hardware technologies and complex memory hierarchies as well as high update rates and changes in workloads by maintaining partitions within one single B+-Tree. This paper includes an experimental evaluation of PBTs optimized write pattern and performance improvements. With PBT transactional throughput under TPC-C increases 30%; PBT results in beneficial sequential write patterns even in presence of updates and maintenance operations.
Pokémon Go was the first mobile Augmented Reality (AR) game that made it to the top of the download charts of mobile applications. However, very little is known about this new generation of mobile online Augmented Reality (AR) games. Existing media usage and technology acceptance theories provide limited applicability to the understanding of its users. Against this background, this research provides a comprehensive framework that incorporates findings from uses & gratification theory (U>), technology acceptance and risk research as well as flow theory. The proposed framework aims at explaining the drivers of attitudinal and intentional reactions, such as continuance in gaming or willingness to conduct in-app purchases. A survey among 642 Pokémon Go players provides insights into the psychological drivers of mobile AR games. Results show that hedonic, emotional and social benefits, and social norms drive, vice versa physical risks (but not privacy risks) hinder consumer reactions. However, the importance of these drivers differs between different forms of user behavior.
Pokémon Go was the first mobile augmented reality (AR) game to reach the top of the download charts of mobile applications. However, little is known about this new generation of mobile online AR games. Existing theories provide limited applicability for user understanding. Against this background, this research provides a comprehensive framework based on uses and gratification theory, technology risk research, and flow theory. The proposed framework aims to explain the drivers of attitudinal and intentional reactions, such as continuance in gaming or willingness to invest money in in-app purchases. A survey among 642 Pokémon Go players provides insights into the psychological drivers of mobile AR games. The results show that hedonic, emotional, and social benefits and social norms drive consumer reactions while physical risks (but not data privacy risks) hinder consumer reactions. However, the importance of these drivers differs depending on the form of user behavior.
Close and safe interaction of humans and robots in joint production environments is technically feasible, however should not be implemented as an end in itself but to deliver improvement in any of a production system’s target dimensions. Firstly, this paper shows that an essential challenge for system integrators during the design of HRC applications is to identify a suitable distribution of available tasks between a robotic and a human resource. Secondly, it proposes an approach to determine task allocation by considering the actual capabilities of both human and robot in order to improve work quality. It matches those capabilities with given requirements of a certain task in order to identify the maximum congruence as the basis for the allocation decision. The approach is based on a study and subsequent generic description of human and robotic capabilities as well as a heuristic procedure that facilities the decision making process.
In den letzten Jahren beschäftigten sich Forscher und Automobilhersteller mit den Voraussetzungen für die Einführung von autonomem Fahren. Für Innovationen und Geschäftsmodelle im Bereich der intelligenten Mobilität, aber auch innerhalb der digitalen Wertschöpfungskette, spielen generell Zuverlässigkeit und Qualität der digitalen Datenübertragung eine entscheidende Rolle. Bevor das autonome Fahren vollständig eingeführt wird, muss man feststellen, welche Anforderungen an die digitale Infrastruktur beachtet werden müssen, gleichzeitig muss die Bedrohungslandschaft für autonomes Fahren analysiert werden.
Die folgende Arbeit beschäftigt sich damit, die Anforderungen und Gefahren zu analysieren und allgemeine Handlungsempfehlungen vorzuschlagen.
Angesichts des breiten Angebotsspektrums neuer Technologien und der Vielzahl verschieden verwendeter Begriffe rund um Industrie 4.0, stehen Unternehmen nicht selten orientierungslos vor der Herausforderung, individuelle Umsetzungsstrategien abzuleiten. Das vorliegende Reifegradmodell ermöglicht die Erfassung bereits im Produktionssystem implementierter Lean Management-Prinzipien und gibt praktikable Antworten auf die evolutionären Visionen, indem es realisierbare und individuelle Migrationspfade in Richtung Industrie 4.0 für Unternehmen aufzeigt.
Zukünftige Montagearbeitsplätze müssen veränderten Herausforderungen, wie z. B. der zunehmenden Anzahl von Mensch Roboter-Kollaborationen, gerecht werden. Die Virtual Reality (VR)-Technik bietet im Rahmen der Arbeitsplatzgestaltung neue Möglichkeiten, diesen veränderten Planungsherausforderungen gerecht zu werden. Die Ausarbeitung stellt eine Methode zur Bewertung des sinnvollen Einsatzes der VR-Technik für einen spezifischen Arbeitsplatz vor. Außerdem wird aufgezeigt, wie die VR-Technik in den Prozess der Arbeitsplatzgestaltung integriert werden kann.
Integrated power semiconductors are often used for applications with cyclic on-chip power dissipation. This leads to repetitive self-heating and thermo-mechanical stress, causing fatigue on the on-chip metallization and possibly destruction by short circuits. Because of this, an accurate simulation of the thermo-mechanical stress is needed already during the design phase to ensure that lifetime requirements are met. However, a detailed thermo mechanical simulation of the device, including the on-chip metallization is prohibitively time-consuming due to its complex structure, typically consisting of many thin metal lines with thousands of vias. This paper introduces a two-step approach as a solution for this problem. First, a simplified but fast simulation is performed to identify the device parts with the highest stress. After, precise simulations are carried out only for them. The applicability of this method is verified experimentally for LDMOS transistors with different metal configurations. The measured lifetimes and failure locations correlate well with the simulations. Moreover, a strong influence of the layout of the on-chip metallization lifetime was observed. This could also be explained with the simulation
method.
In this paper we describe the design and development process of an electromagnetic picker for rivets. These rivets are used in a production process of leather or textile design objects like riveted waist belts or purses. The picker is designed such that it replaces conventional mechanical pickers thus avoiding mechanical wear problems and increasing the process quality. The paper illustrates the challenges in the design process of this mechatronic system. The design process was based on both simulation and experiments leading to a prototype that satisfies the requirements.
In this article, liposome-based coatings aiming to control drug release from therapeutic soft contact lenses (SCLs) materials are analyzed. A PHEMA based hydrogel material loaded with levofloxacin is used as model system for this research. The coatings are formed by polyelectrolyte layers containing liposomes of 1,2-dimyristoyl-sn-glycero-3- phosphocholine (DMPC) and DMPC1cholesterol (DMPC1 CHOL). The effect of friction and temperature on the drug release is investigated. The aim of the friction tests is to simulate the blinking of the eyelid in order to verify if the SCLs materials coated with liposomes are able to keep their properties, in particular the drug release ability. It was observed that under the study conditions, friction did not affect significantly the drug release from the liposome coated PHEMA material. In contrast, increasing the temperature of release leads to an increase of the drug diffusion rate through the hydrogel. This phenomenon is recorded both in the control and in the coated samples.
This paper presents an approach for label-free brain tumor tissue typing. For this application, our dual modality microspectroscopy system combines inelastic Raman scattering spectroscopy and Mie elastic light scattering spectroscopy. The system enables marker-free biomedical diagnostics and records both the chemical and morphologic changes of tissues on a cellular and subcellular level. The system setup is described and the suitability for measuring morphologic features is investigated.
The influence of turbidity on the Raman signal strengths of condensed matter is theoretically analyzed and measured with laboratory - scale equipment for remote sensing. The results show the quantitative dependence of back- and forward-scattered signals on the thickness and elastic-scattering properties of matter. In the extreme situation of thin, highly turbid layers, the measured Raman signal strengths exceed their transparent analogs by more than a factor of ten. The opposite behavior is found for thick layers of low turbidity, where the presence of a small amount of scatterers leads to a decrease of the measured signal. The wide range of turbidities appearing in nature is experimentally realized with stacked polymer layers and solid/liquid dispersions, and theoretically modeled by the equation of radiative transfer using the analytical diffusion approximation or random walk simulations.
Nenne sie niemals Senioren!
(2017)
Bei großen Sportereignissen wie Fußball-, Welt- und Europameisterschaften oder Olympischen Spielen geht es für Verbände und offizielle Sponsoren um Millionen, entsprechend scharf verteidigen sie ihre Werberechte. Burger King zeigt, wie sich dieses „Monopol“ kreativ umgehen lässt. Im folgenden Beitrag werden exemplarisch zwei Ambush-Marketing-Aktivitäten von Burger King im Rahmen der Fußball Europameisterschaften 2016 vorgestellt. Nicht-Sponsor Burger King setzte Ambush Marketing dabei gezielt und kreativ im Rahmen der EM ein, um gegen den offiziellen UEFA-Sponsor und Wettbewerber McDonald‘s Punkte zu sammeln.
Energy transfer kinetics in photosynthesis as an inspiration for improving organic solar cells
(2017)
Clues to designing highly efficient organic solar cells may lie in understanding the architecture of light harvesting systems and exciton energy transfer (EET) processes in very efficient photosynthetic organisms. Here, we compare the kinetics of excitation energy tunnelling from the intact phycobilisome (PBS) light harvesting antenna system to the reaction center in photosystem II in intact cells of the cyanobacterium Acaryochloris marina with the charge transfer after conversion of photons into photocurrent in vertically aligned carbon nanotube (va- CNT) organic solar cells with poly(3-hexyl)thiophene (P3HT) as the pigment. We find that the kinetics in electron hole creation following excitation at 600 nm in both PBS and va-CNT solar cells to be 450 and 500 fs, respectively. The EET process has a 3 and 14 ps pathway in the PBS, while in va-CNT solar cell devices, the charge trapping in the CNT takes 11 and 258 ps. We show that the main hindrance to efficiency of va CNT organic solar cells is the slow migration of the charges after exciton formation.
In this paper a method for the generation of gSPM with ontology-based generalization was presented. The resulting gSPM was modeled with BPMN/BPMNsix in an efficient way and could be executed with BPMN workflow engines. In the next step the implementation of resource concepts, anatomical structures, and transition probabilities for workflow execution will be realized.
Due to rapidly changing technologies and business contexts, many products and services are developed under high uncertainties. It is often impossible to predict customer behaviors and outcomes upfront. Therefore, product and service developers must continuously find out what customers want, requiring a more experimental mode of management and appropriate support for continuously conducting experiments. We have analytically derived an initial model for continuous experimentation from prior work and matched it against empirical case study findings from two startup companies. We examined the preconditions for setting up an experimentation system for continuous customer experiments. The resulting RIGHT model for Continuous Experimentation (Rapid Iterative value creation Gained through High-frequency Testing) illustrates the building blocks required for such a system and the necessary infrastructure. The major findings are that a suitable experimentation system requires the ability to design, manage, and conduct experiments, create so-called minimum viable products or features, link experiment results with a product roadmap, and manage a flexible business strategy. The main challenges are proper, rapid design of experiments, advanced instrumentation of software to collect, analyse, and store relevant data, and integration of experiment results in the product development cycle, software development process, and business strategy. This summary refers to the article The RIGHT Model for Continuous Experimentation, published in the Journal of Systems and Software [Fa17].
The business landscape is changing radically because of software. Companies in all industry sectors are continously finding new flexibilities in this programmable world. They are able to deliver new functionalities even after the product is already in the customer's hands. But success is far from guaranteed if they cannot validate their assumptions about what their customers actually need. A competitor with better knowledge of customer needs can disrupt the market in an instant.
This book introduces continuous experimentation, an approach to continuously and systematically test assumptions about the company's product or service strategy and verify customers' needs through experiments. By observing how customers actually use the product or early versions of it, companies can make better development decisions and avoid potentially expensive and wasteful activities. The book explains the cycle of continuous experimentation, demonstrates its use through industry cases, provides advice on how to conduct experiments with recipes, tools, and models, and lists some common pitfalls to avoid. Use it to get started with continuous experimentation and make better product and service development decisions that are in-line with your customers' needs.
THE PROBLEM: Companies create problems for customers and employees when product innovation goes unmanaged. Eventually, excessive operational complexity hurts the bottom line.
THREE SOLUTIONS: Focus on product integration, not product proliferation. Make sure your product developers work closely with customerfacing and operational employees. And settle on a high-level purpose that can guide decision making.
Royal Philip's goal was to use innovation to improve the lives of three billion people a year by 2025. To reach that goal, the company was shifting from selling medical products in a transactional manner to providing integrated healthcare solutions based on digital health technology ("HealthTech").
This shift required a dual transformation. On one hand, the company needed to transform how healthcare was conducted. Healthcare professionals would have to change the way they worked and reimbursement schemes needed to change to incentivize payers, providers, and patients in vastly different ways. On the other hand, Philips needed to redesign how it worked internally. The company componentized its business, introduced digital platforms, and co-created solutions with the various stakeholders of the healthcare industry.
In other words: Royal Philips was transforming itself in order to reinvent healthcare in the digital age.
AUDI AG has historically focused on producing and selling premium vehicles but has begun to experiment with providing mobility services, built around car sharing. Its response to the so-called sharing economy addressed strategic and transformational challenges. Strategically, the company pursued additional sources of revenue from targeted, premium mobility services, rather than the less segmented services provided by competitors such as BMW and Zipcar. AUDI AG also transformed its organizational structure, processes and architecture to balance autonomy for innovation and integration for competitiveness.
In 2016, German car manufacturer the Audi Group (AUDI AG) was working on an expanding array of digital innovations. The goals of these innovations varied, and included strengthening customer- and employee-facing processes, digitally enhancing existing products, and developing new, potentially disruptive business models. Audi’s IT unit was critical to each of these efforts. Based on personal interviews with 11 IT- and non-IT executives at Audi, this case examines the different ways in which digitization can help to enhance and transform an organization’s processes, products, and business models. The case also highlights the challenges that arise as large companies “digitize.”
IT platforms as the foundation of digitized processes and products are vital in a digital economy. However, many companies’ platforms are liabilities, not strategic assets because of their complexity. Consequently, companies initiate IT complexity reduction programs. But these technology-centric programs at best provide temporary relief. Soon after, companies’ platforms become just as complex as before. Based on four case studies, we identify three non-technical drivers of platform complexity: (1) Lacking awareness of consequences business decisions have on platform complexity, (2) Lacking motivation to avoid platform complexity, (3) Lacking authority to protect platforms from complexity. We propose measures to address these drivers that can help achieve more sustainable impact on platform complexity: (1) Removing information asymmetries between those creating complexity and those dealing with complexity, (2) Redefining incentives to include long-term effects on platform complexity, (3) Redressing power imbalances between those who create complexity and those who have to manage it.
This paper investigates the electrothermal stability and the predominant defect mechanism of a Schottky gate AlGaN/GaN HEMT. Calibrated 3-D electrothermal simulations are performed using a simple semiempirical dc model, which is verified against high-temperature measurements up to 440°C. To determine the thermal limits of the safe operating area, measurements up to destruction are conducted at different operating points. The predominant failure mechanism is identified to be hot-spot formation and subsequent thermal runaway, induced by large drain–gate leakage currents that occur at high temperatures. The simulation results and the high temperature measurements confirm the observed failure patterns.