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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.
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.
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.
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.
Painting galleries typically provide a wealth of data composed of several data types. Those multivariate data are too complex for laymen like museum visitors to first, get an overview about all paintings and to look for specific categories. Finally, the goal is to guide the visitor to a specific painting that he wishes to have a more closer look on. In this paper we describe an interactive visualization tool that first provides such an overview and lets people experiment with the more than 41,000 paintings collected in the web gallery of art. To generate such an interactive tool, our technique is composed of different steps like data handling, algorithmic transformations, visualizations, interactions, and the human user working with the tool with the goal to detect insights in the provided data. We illustrate the usefulness of the visualization tool by applying it to such characteristic data and show how one can get from an overview about all paintings to specific paintings.
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.
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.
A gate driver approach is presented for the reduction of turn-on losses in hard switching applications. A significant turn-on loss reduction of up to 55% has been observed for SiCMOSFETs. The gate driver approach uses a transformer which couples energy from the power path back into the gate path during switching events, providing increased gate driver current and thereby faster switching speed.
The gate driver approach was tested on a boost converter running at a switching frequency up to 300 kHz. With an input voltage of 300V and an output voltage of 600V, it was possible to reduce the converter losses by 8% at full load. Moreover, the output power range could be extended by 23% (from 2.75kW to 3.4 kW) due to the reduction of the turn-on losses.
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.
Cell-cell and cell-extracellular matrix (ECM) adhesion regulates fundamental cellular functions and is crucial for cell-material contact. Adhesion is influenced by many factors like affinity and specificity of the receptor-ligand interaction or overall ligand concentration and density. To investigate molecular details of cell ECM and cadherins (cell-cell) interaction in vascular cells functional nanostructured surfaces were used Ligand-functionalized gold nanoparticles (AuNPs) with 6-8 nm diameter, are precisely immobilized on a surface and separated by non-adhesive regions so that individual integrins or cadherins can specifically interact with the ligands on the AuNPs. Using 40 nm and 90 nm distances between the AuNPs and functionalized either with peptide motifs of the extracellular matrix (RGD or REDV) or vascular endothelial cadherins (VEC), the influence of distance and ligand specificity on spreading and adhesion of endothelial cells (ECs) and smooth muscle cells (SMCs) was investigated. We demonstrate that RGD-dependent adhesion of vascular cells is similar to other cell types and that the distance dependence for integrin binding to ECM-peptides is also valid for the REDV motif. VEC-ligands decrease adhesion significantly on the tested ligand distances. These results may be helpful for future improvements in vascular tissue engineering and for development of implant surfaces.
Intermediate filament reorganization dynamically influences cancer cell alignment and migration
(2017)
The interactions between a cancer cell and its extracellular matrix (ECM) have been the focus of an increasing amount of investigation. The role of the intermediate filament keratin in cancer has also been coming into focus of late, but more research is needed to understand how this piece fits in the puzzle of cytoskeleton-mediated invasion and metastasis. In Panc-1 invasive pancreatic cancer cells, keratin phosphorylation in conjunction with actin inhibition was found to be sufficient to reduce cell area below either treatment alone. We then analyzed intersecting keratin and actin fibers in the cytoskeleton of cyclically stretched cells and found no directional correlation. The role of keratin organization in Panc-1 cellular morphological adaptation and directed migration was then analyzed by culturing cells on cyclically stretched polydimethylsiloxane (PDMS) substrates, nanoscale grates, and rigid pillars. In general, the reorganization of the keratin cytoskeleton allows the cell to become more ‘mobile’- exhibiting faster and more directed migration and orientation in response to external stimuli. By combining keratin network perturbation with a variety of physical ECM signals, we demonstrate the interconnected nature of the architecture inside the cell and the scaffolding outside of it, and highlight the key elements facilitating cancer cell-ECM interactions.
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.
This paper describes a new method for condition monitoring of a roller chain. In contrast to conventional methods, no additional accelerometers are used to measure and interpret frequency spectra but the chain condition is evaluated using an easy to interpret similarity measure based on correlation functions using the driving motor torque. An additional clustering of current data and reference measurements yields an easy to understand representation of the chain condition.
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.
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.
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.
Social sustainable supply chain management in the textile and apparel industry : a literature review
(2017)
So far, a vast amount of studies on sustainability in supply chain management have been conducted by academics over the last decade. Nevertheless, socially related aspects are still neglected in the related discussion. The primary motivation of the present literature review has arisen from this shortcoming, thus the key purpose of this study is to enrich the discussion by providing a state of-the-art, focusing exclusively on social issues in sustainable supply chain management (SSCM) by considering the textile/apparel sector as the field of application. The authors conduct a literature review, including content analysis which covers 45 articles published in English peer-reviewed journals, and proposes a comprehensive map which integrates the latest findings on socially related practices in the textile/apparel industry with the dominant conceptualization in order to reveal potential research areas in the field. The results show an ongoing lack of investigation regarding the social dimension of the triple bottom line in SSCM. Findings indicate that a company’s internal orientation is the main assisting factor in sustainable supply chain management practices. Further, supplier collaboration and assessment can be interpreted as an offer for suppliers deriving from stakeholders and a focal company’s management of social risk. Nevertheless, suppliers do also face or even create huge barriers in improving their social performance. This calls for more empirical research and qualitative or quantitative survey methods, especially at the supplier level located in developing countries.
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.
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.
In times of dynamic markets, enterprises have to be agile to be able to quickly react to market influences. Due to the increasing digitization of products, the enterprise IT often is affected when business models change. Enterprise Architecture Management (EAM) targets a holistic view of the enterprise’ IT and their relations to the business. However, Enterprise Architectures (EA) are complex structures consisting of many layers, artifacts and relationships between them. Thus, analyzing EA is a very complex task for stakeholders. Visualizations are common vehicles to support analysis. However, in practice visualization capabilities lack flexibility and interactivity. A solution to improve the support of stakeholders in analyzing EAs might be the application of visual analytics. Starting from a systematic literature review, this article investigates the features of visual analytics relevant for the context of EAM.
We present a fully automatic approach to real-time 3D face reconstruction from monocular in-the-wild videos. With the use of a cascaded-regressor-based face tracking and a 3D morphable face model shape fitting, we obtain a semidense 3D face shape. We further use the texture information from multiple frames to build a holistic 3D face representation from the video footage. Our system is able to capture facial expressions and does not require any person specific training. We demonstrate the robustness of our approach on the challenging 300 Videos in the Wild (300- VW) dataset. Our real-time fitting framework is available as an open-source library at http://4dface.org.
It is assumed that more education leads to better understanding of complex systems. Some researchers, however, find indications that simple mechanisms like stocks and flows are not well understood even by people who have passed higher education. In this paper, we test people’s understanding of complex systems with the widely studied stock-and-flow (SF) tasks. SF tasks assess people’s understanding of the interplay between stocks and flows. We investigate SF failure of domain experts and novices in different knowledge domains. In particular, we compare performance on the original study’s bathtub task with the square wave pattern with two alternative cover stories from the engineering and business domains on different groups of business and engineering students from different semesters. Further, we show that, while engineering students perform better than business students, with progressing in higher education, students may lose the capability of dealing with simple SF tasks. We thus find hints on déformation professionelle in higher education.
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.
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.
This research is about Omnichannel Retailing and addresses the question how the omnichanneling of retailers in the fashion market can be measured. Our sources will include books, interviews, newspapers and scientific databases.
Omnichanneling is a current topic in the fashion market, retailers all over the world face the question on how to adapt to the challenges Omnichannel Retailing sets. We are going to define what Omnichanneling is by explaining the differences between Multiple-, Multi-, Cross- and Omnichannel Retailing. After we defined omnichanneling itself, we took a set of 26 retailers to evaluate regarding their Omnichannel capabilities. Then we create an index with criteria that can measure the Omnichannel capability of each retailer.
The Omnichannel Score is based on 31 criteria, which analyze the retailers in offline, online, mobile and social aspects enables to see differences between retailers. Our findings were that retailers in the US fashion market are more advanced in Omnichannel Retailing than retailers in the German fashion market. Our top three Omnichannel retailers were Sears with an Omnichannel Score of 91, followed by KOHL’S and Marks&Spencer, both with a Omnichannel Score of 88. The best Omnichannel Retailer from Germany was Adidas with the fourth place and an Omnichannel Score of 81.
There is no doubt that the amplification of channel integration towards an omni-channel structure is a powerful idea whose time has finally come. The digitally cross-linked world postulates all-encompassing, ubiquitous, and unobtrusive future services. In the concomitant, increasingly competitive market, retailers are starting to lay the foundation for omnichannel, meeting the expectations of a digitally cunning audience wanting their shopping experience to be as seamless and uncomplicated as possible. Nevertheless, recent researches show that there are still enough avenues for further research on omnichannel. Until now, the performance of companies was solely considered by experts from a suppliers’ point of view. It would be rather interesting to find out whether the desire to meet the increased cus-tomer expectations is also recognized by the customers themselves. This paper seeks to answering how the purchasing behavior has changed and what customers demand. In addition, it elaborates the opportunities that are promoted by omni-channel. Searching out all the effects, the paper will get to a final step, where it can be attested how the omnichannel performance of fashion and lifestyle retailers can be measured from a consumers’ perspective by developing an exclusive index. The study is confined to four fashion and lifestyle retailers: Hugo Boss AG, Levi Strauss & Co, Pull and Bear as well as COS. Using the scientific method of mystery shopping and a multi-item checklist including 54 key performance indicators, the paper aims to examine to which extend the four selected retailers provide a seamless customer journey, according to the five decision-making phases.
The purpose of this paper is to determine the relevance of social media for luxury brand management. It employs both a multi-methodological approach: After analyzing the online performance of the three luxury brands Burberry, Louis Vuitton and Gucci, the empirical research includes a survey as well as an eye tracking test executed with Tobii Studio. The findings reveal that online and social media have given luxury fashion businesses the opportunity to establish a sustainable interaction with their customers and distinguish themselves from the competition. Still, the online business holds many challenges for luxury companies to overcome. This paper gives instructions as to how social media can be effectively incorporated into a luxury company.
The conventional view of the value-creation chain suggests offering high-value propositions at the product level (in terms of benefits provided by elements of the product) to attain high-value perceptions at the customer level, which should ultimately result in high-value appropriation at the firm level (i.e. relationship, volume, pricing and financial success). This study challenges this view and provides a differentiated understanding of the value creation chain. With a multi-industry sample of 339 companies and a sample of 626 customers to validate managerial assessments, the authors apply a configurational approach to identify whether and to what extent offering high-value propositions at the product level is necessary or sufficient for achieving superior value perceptions at the customer level and high-value appropriation at the firm level. Taking into account the company-internal and company-external environment of the value-creation chain, the study identifies seven value creation chain constellations.
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.
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.
Digitisation forms a part of Industrie 4.0 and is both threatening, but also providing an opportunity to transform business as we know it; and can make entire business models redundant. Although companies might realise the need to digitise, many are unsure of how to start this digital transformation. This paper addresses the problems and challenges faced in digitisation, and develops a model for initialising digital transformation in enterprises. The model is based on a continuous improvement cycle, and also includes triggers for innovative and digital thinking within the enterprise. The model was successfully validated in the German service sector.
Propofol is a commonly used intravenous general anesthetic. Multi-capillary column (MCC) coupled ion-mobility spectrometry (IMS) can be used to quantify exhaled propofol, and thus estimate plasma drug concentration. Here, we present results of the calibration and analytical validation of a MCC/IMS pre-market prototype for propofol quantification in exhaled air.
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.
Purpose: The purpose of this study was to investigate the value of the web representation of certain fashion hot spots and how these results can be shown on fashion maps in an illustrated way.
Design/methodology/approach: A new ranking was created, which was evaluated with a self-instructed index, to gain solid results. Numbers were collected from Google, Instagram, Facebook, Twitter and web.alert.io. Additionally, fashion maps were created for an illustrative visualization of the results.
Findings: Compared with the ranking of a trend forecasting agency, called Global Language Monitor, which concepted a ranking of non-virtual fashion cities, the web representation and therefore the ranking of the research project, differs mainly in the situation of the cities among the first 10, viz. the rank on which a city occurs, but fewer in the actual cities mentioned.
Research limitations: The research was limited to subjective analysis of data, leading to partly subjective results, as well as the selected number of social media platforms, that had been used.
Originality/value: This is the first study to explore the web representation value of fashion metropolises in comparison to their non-virtual ranking. The results are partly based on results that already existed, concerning transformations of fashion cities or in general which cities own the status of a fashion city.
Purpose: The purpose of this paper is to examine the service of the new business model Curated Shopping in the fashion industry as well as to analyze if the service provides a higher costumer added value in comparison to traditional services in retail stores and e-commerce platforms. It gives implications to curated shop operators how to optimize the service in each stage of the customer buying process.
Design/methodology/approach: The research methodology applied is an empirical study that uses the principal of mystery shopping in order to investigate the provided services during the selling process.
Findings: The study showed that information about the customer should be collected carefully and as holistic as possible in order to assort a suitable outfit. The consumer is able to benefit from the service by saving time and enjoying a stress-free way of shopping. Nevertheless there are limitations in the personal service to give individual and inspiring advice by the curator caused by the physical distance to the customer.
Research limitations: The survey was conducted under 10 mystery shoppers and 4 curated shop operators in Germany, limiting findings to these mystery shoppers and operators.
Practical implications: One implication for the shop operators is to collect consumer information carefully and expand the assortment and brand portfolio in order to provide fashion goods to inspire the consumer. The shop operators are on the right track still there is huge potential to provide a more shopper-oriented service.
Newly developed active pharmaceutical ingredients (APIs) are often poorly soluble in water. As a result the bioavailability of the API in the human body is reduced. One approach to overcome this restriction is the formulation of amorphous solid dispersions (ASDs), e.g., by hot-melt extrusion (HME). Thus, the poorly soluble crystalline form of the API is transferred into a more soluble amorphous form. To reach this aim in HME, the APIs are embedded in a polymer matrix. The resulting amorphous solid dispersions may contain small amounts of residual crystallinity and have the tendency to recrystallize. For the controlled release of the API in the final drug product the amount of crystallinity has to be known. This review assesses the available analytical methods that have been recently used for the characterization of ASDs
and the quantification of crystalline API content. Well established techniques like near- and mid-infrared spectroscopy (NIR and MIR, respectively), Raman spectroscopy, and emerging ones like UV/VIS, terahertz, and ultrasonic spectroscopy are considered in detail. Furthermore, their advantages and limitations are discussed with regard to general practical applicability as process analytical technology (PAT) tools in industrial manufacturing. The review focuses on spectroscopic methods which have been proven as most suitable for in-line and on-line process analytics. Further aspects are spectroscopic techniques that have been or could be integrated into an extruder.
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.
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.
Condition Monitoring for mechanical systems like bearings or transmissions is often done by analysing frequency spectra obtained from accelerometers mounted to the components under observation. Although this approach gives a high amount on information about the system behaviour, the interpretation of the resulting spectra requires expert knowledge, that is, a deep understanding of the effect on condition deterioration on the measured spectra. However, an increasing number of condition monitoring applications demands other representations of the measured signals that can be easily interpreted even by non–experts. Therefore, the objective of this paper is to develop an approach for processing measured process data in order to obtain an easy to interpret measure for assessing the component condition. The main idea is to evaluate the deterioration of a component condition by computing the correlation function of current measurements with past measurements in order to detect a component condition deterioration from a change in these correlation functions. Besides the simplicity of the obtained measure, this approach opens the opportunity for integrating a model based approach as well. The developed method is tested based on a condition monitoring application in a roller chain.
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.
Für Führungskräfte sind Widersprüche und paradoxe Spannungen eine alltägliche Erfahrung. Dennoch sehen viele Führungskräfte Widersprüche als etwas an, das »eigentlich« nicht da sein sollte. Häufig blenden sie die widersprüchlichen Signale aus und ignorieren die Paradoxie. Oder sie nehmen die Spannungen als störend und belastend wahr und versuchen die Paradoxie zu lösen. Die Management- und Organisationsforschung zeigt jedoch: Paradoxien sind in Organisationen omnipräsent. Und sie sind nicht dauerhaft lösbar. Welche Konsequenzen hat das für unser Verständnis von Management?
Best Practice-Modelle und Change- Weisheiten erfreuen sich großer Beliebtheit, was sich wohl damit erklären lässt, dass sie bei den Verantwortlichen komplexitätsreduzierend wirken und Unsicherheit abbauen. Allerdings sind Organisationen voller Widersprüche, reagieren oft irrational und folgen nicht unbedingt den durchgeplanten Entwürfen des Change Managements. Manche Fragen in Organisationen sind unlösbar, und die Organisationen pendeln bei ihrer Lösungssuche zwischen entgegengesetzten Polen hin und her. Best Practices können als Idealvorstellungen die in sie gesetzten Erwartungen oft nicht erfüllen. Dort, wo sie an ihre Grenzen stoßen, erscheint es ratsam, sich auf die fundamentalen Kräfte des Wandels wie Paradoxien, Ambiguität, Komplexität und Nicht-Steuerbarkeit einzulassen.
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.
Die meisten Unternehmen steuern ihr operatives Marketing, ohne die Effektivität und die Effizienz der dabei eingesetzten Instrumente zu quantifizieren - in Anbetracht der Höhe typischer Marketingbudgets ein kritischer Befund. Wie kann man hier Abhilfe schaffen? Ein Blick auf eines der Schlüsselkonzepte von Industrie 4.0 zeigt einen möglichen Weg auf.
Data Integration of heterogeneous data sources relies either on periodically transferring large amounts of data to a physical Data Warehouse or retrieving data from the sources on request only. The latter results in the creation of what is referred to as a virtual Data Warehouse, which is preferable when the use of the latest data is paramount. However, the downside is that it adds network traffic and suffers from performance degradation when the amount of data is high. In this paper, we propose the use of a readCheck validator to ensure the timeliness of the queried data and reduced data traffic. It is further shown that the readCheck allows transactions to update data in the data sources obeying full Atomicity, Consistency, Isolation, and Durability (ACID) properties.
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.
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.