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An integrated synchronous buck converter with a high resolution dead time control for input voltages up to 48V and 10MHz switching frequency is presented. The benefit of an enhanced dead time control at light loads to enable zero voltage switching at both the high-side and low-side switch at low output load is studied. This way, compact multi-MHz DCDC converters can be implemented at high efficiency over a wide load current range. The concept also eliminates body diode forward conduction losses and minimizes reverse recovery losses. A dead time resolution of 125 ps is realized by an 8-bit differential delay chain. A further efficiency enhancement by soft switching at the high-side switch at light load is achieved with a voltage boost of the switching node by dead time control in forced continuous conduction mode. The monolithic converter is implemented in an 180nm high-voltage BiCMOS technology. At V IN = 48V, V OUT = 5V, 50mA load, 10MHz switching frequency and 500 nH output inductance, the efficiency is measured to be increased by 14.4% compared to a conventional predictive dead time control. A peak efficiency of 80.9% is achieved at 12V input.
In recent years, significant progress has been made on switched-capacitor DC-DC converters as they enable fully integrated on-chip power management. New converter topologies overcame the fixed input-to-output voltage limitation and achieved high efficiency at high power densities. SC converters are attractive to not only mobile handheld devices with small input and output voltages, but also for power conversion in IoE, industrial and automotive applications, etc. Such applications need to be capable of handling widely varying input voltages of more than 10V, which requires a large amount of conversion ratios. The goal is to achieve a fine granularity with the least number of flying capacitors. In [1] an SC converter was introduced that achieves these goals at low input voltage VIN ≤ 2.5V. [2] shows good efficiency up to VIN = 8V while its conversion ratio is restricted to ≤1/2 with a limited, non-equidistant number of conversion steps. A particular challenge arises with increasing input voltage as several loss mechanisms like parasitic bottom-plate losses and gate-charge losses of high-voltage transistors become of significant influence. High input voltages require supporting circuits like level shifters, auxiliary supply rails etc., which allocate additional area and add losses [2-5]. The combination of both increasing voltage and conversion ratios (VCR) lowers the efficiency and the achievable output power of SC converters. [3] and [5] use external capacitors to enable higher output power, especially for higher VIN. However, this is contradictory to the goal of a fully integrated power supply.
The power supply is one of the major challenges for applications like internet of things IoTs and smart home. The maintenance issue of batteries and the limited power level of energy harvesting is addressed by the integrated micro power supply presented in this paper. Connected to the 120/230 Vrms mains, which is one of the most reliable energy sources and anywhere indoor available, it provides a 3.3V DC output voltage. The micro power supply consists of a fully integrated ACDC and DCDC converter with one external low voltage SMD buffer capacitor. The micro power supply is fabricated in a low cost 0.35 μm 700 V CMOS technology and covers a die size of 7.7 mm². The use of only one external low voltage SMD capacitor, results in an extremely compact form factor. The ACDC is a direct coupled, full wave rectifier with a subsequent bipolar shunt regulator, which provides an output voltage around 17 V. The DCDC stage is a fully integrated 4:1 SC DCDC converter with an input voltage as high as 17 V and a peak efficiency of 45 %. The power supply achieves an overall output power of 3 mW, resulting in a power density of 390 μW/mm². This exceeds prior art by a factor of 11.
A high-voltage replica based current sensor is presented, along with challenges and design techniques which are rarely discussed in literature so far. The performance is evaluated by detailed small signal and large signal analysis. By dedicated placing of high-voltage cascode devices, while keeping as many low-voltage devices as possible, a high gain-bandwidth product is achieved. A decoupling and biasing circuit is introduced which improves the response time of the current sensor at on/off transitions by a factor of five. The current sensor is implemented in a 180nm HV BiCMOS technology. The sensor achieves a DC loop gain of 83 dB and a gain-bandwidth product of 7 MHz. With the proposed techniques, the gain-bandwidth product is increased by a factor of six. The measurable current range is between 60mA and 1.5 A. The performance is demonstrated in a 500 kHz buck converter at an input voltage of 40V. The overall circuit concept is suitable for 100V and beyond, enabling high performance power management designs including switched mode power supplies and motor applications.
This article analyses and compares the performance of regulators in the fields of finance and sport, especially cycling. I hypothesize that the courses of crises or scandals is the best time to study the lessons of regulatory response. First, I take into account the differences in both finance and cycling by looking at the nature of the rules and institutions governing the field. Second, I estimate the attention effect on new regulation in response to crises or scandals. The interest of the paper is in the alignment of incentives to prevent regulatory capture and to ensure accountability and enforceability. The paper concludes that the differences hold important lessons that call for the reform of rules and institutions governing finance and cycling alike.
This paper presents a compact 3 kW bidirectional GaN-HEMT DC/DC converter for 360V to 400-500 V. A very high efficiency has been reached by applying a zero voltage turn-on in conjunction with a negative gate-source voltage, even though normally-off HEMTs are used. Further improvements were achieved by adapting the switching frequency to the load current and output voltage, as will be explained by means of the loss contribution of the specific elements for a constant and an adaptive switching frequency. Measurements have shown a high converter efficiency exceeding 99% over a wide output power range of up to 3 kW.
The financial crisis of 2007-2010 was probably one of the greatest, most lustrous black-swan events that people of our generation(s) will experience – and at its heart, it was a dynamic phenomenon. It is stated in the vision of the System Dynamics Society that we aspire to transform society by influencing decision-making. Yet, it seems as if system dynamics did not play any significant role in this crisis: we did not examine the markets, we did not provide insights to banks, and we did not warn governments or the people. In our presentation we describe the dynamics involved in a housing bubble, and describe what made the last one different. With the insights gained from this exercise we conclude that, from a system dynamics perspective, the dimension of the financial crisis of 2007-2009 was eminently foreseeable, which will lead us to pose the following question: where were we as a field while this crisis was unfolding, why were we not active players? We present a range of potential answers to this question, hoping to provoke some reflection… and maybe some (re)action.
3D morphable face models are a powerful tool in computer vision. They consist of a PCA model of face shape and colour information and allow to reconstruct a 3D face from a single 2D image. 3D morphable face models are used for 3D head pose estimation, face analysis, face recognition, and, more recently, facial landmark detection and tracking. However, they are not as widely used as 2D methods - the process of building and using a 3D model is much more involved.
In this paper, we present the Surrey Face Model, a multi resolution 3D morphable model that we make available to the public for non-commercial purposes. The model contains different mesh resolution levels and landmark point annotations as well as metadata for texture remapping. Accompanying the model is a lightweight open-source C++ library designed with simplicity and ease of integration as its foremost goals. In addition to basic functionality, it contains pose estimation and face frontalisation algorithms. With the tools presented in this paper, we aim to close two gaps. First, by offering different model resolution levels and fast fitting functionality, we enable the use of a 3D Morphable Model in time-critical applications like tracking. Second, the software library makes it easy for the community to adopt the 3D morphable face model in their research, and it offers a public place for collaboration.
In this note we look at anisotropic approximation of smooth functions on bounded domains with tensor product splines. The main idea is to extend such functions and then use known approximation techniques on Rd. We prove an error estimate for domains for which bounded extension operators exist. This obvious approach has some limitations. It is not applicable without restrictions on the chosen coordinate degree even if the domain is as simple as the unit disk. Further for approximation on Rd there are error estimates in which the grid widths and directional derivatives are paired in an interesting way. It seems impossible to maintain this property using extension operators.
In contrast to IC design, MEMS design still lacks sophisticated component libraries. Therefore, the physical design of MEMS sensors is mostly done by simply drawing polygons. Hence, the sensor structure is only given as plain graphic data which hinders the identification and investigation of topology elements such as spring, anchor, mass and electrodes. In order to solve this problem, we present a rule-based recognition algorithm which identifies the architecture and the topology elements of a MEMS sensor. In addition to graphic data, the algorithm makes use of only a few marking layers, as well as net and technology information. Our approach enables RC-extraction with commercial field solvers and a subsequent synthesis of the sensor circuit. The mapping of the extracted RC-values to the topology elements of the sensor enables a detailed analysis and optimization of actual MEMS sensors.
It is known that the costs related with drug research and development (R&D) and the timelines to develop a new drug increased over the past years. In parallel, the success rates of drug projects along the pharmaceutical R&D phases are still very low, and the outcome of all R&D efforts is stagnating. In consequence, the R&D efficiency defined as the financial investment per drug has been steadily decreasing. As innovation is the major growth driver of the pharmaceutical industry, reliable data on R&D efficiency and new concepts to overcome these challenges are of great interest for R&D managers and the sustainability of the pharmaceutical industry as a whole. This book chapter reviews publications on R&D performance indicators of the past years, such as the success rates and timelines per phase. Additionally, it illustrates the factors influencing the success rates, timelines, and costs of pharmaceutical R&D most and, thus, the denominators of the R&D efficiency.
This article is a review of the book "Brain computation as hierarchical abstraction" by Dana H. Ballard published by MIT press in 2015. The book series computational neuroscience familiarizes the reader with the computational aspects of brain functions based on neuroscientific evidence. It provides an excellent introduction of the functioning, i.e. the structure, the network and the routines of the brain in our daily life. The final chapters even discuss behavioral elements such as decision-making, emotions and consciousness. These topics are of high relevance in other sciences such as economics and philosophy. Overall, Ballard’s book stimulates a scientifically well-founded debate and, more importantly, reveals the need of an interdisciplinary dialogue towards social sciences.
This paper is a commentary on the book ‘Probability and stochastic processes’ from Ionut Florescu. The book is an excellent introduction to both probability theory and stochastic processes. It provides a comprehensive discussion of the main statistical concepts including the theorems and proofs. The introduction to probability theory is easy accessible and a perfect starting point for undergraduate students even with majors in other subjects than science, such as business or engineering. The book is also up-to-date because it includes programming code for simulations. However, the book has some weaknesses. It is less convincing in more advanced topics of stochastic theory and it does not include solutions to excises and recent research trends.
A lot of people need help in their daily life to wash, select and manage their clothing. The goal of this work is to design an assistant system (eKlarA) to support the user by giving recommendations to choose the clothing combinations, to find the clothing and to wash the clothing. The idea behind eKlarA is to generate a system that uses sensors to identify the clothing and their state in the clothing cycle. The clothing cycle consists of the stations: closets, laundry basket and washing machine in one or several places. The system uses the information about the clothing, weather and calendar to support the user in the different steps of the clothing cycle. The first prototype of this system has been developed and tested. The test results are presented in this work.
A seamless convergence of the digital and physical factory aiming in personalized Product Emergence Process (PPEP) for smart products within ESB Logistics Learning Factory at Reutlingen University.
A completely new business model with reference to Industrie4.0 and facilitated by 3D experience software in today's networked society in which customers expect immediate responses, delightful experience and simple solutions is one of the mission scenarios in the ESB Logistics Learning Factory at ESB Business School (Reutlingen University).
The business experience platform provides software solutions for every organization in the company respectively in the factory. An interface with dashboards, project management apps, 3D - design and construction apps with high end visualization, manufacturing and simulation apps as well as intelligence and social network apps in a collaborative interactive environment help the user to learn the creation of a value end to end process for a personalized virtual and later real produced product.
Instead of traditional ways of working and a conventional operating factory real workers and robots work semi-intuitive together. Centerpiece in the self-planned interim factory is the smart personalized product, uniquely identifiable and locatable at all times during the production process – a scooter with an individual colored mobile phone – holder for any smart phone produced with a 3D printer in lot size one. Smart products have in the future solutions incorporated internet based services – designed and manufactured - at the costs of mass products. Additionally the scooter is equipped with a retrievable declarative product memory. Monitoring and control is handled by sensor tags and a raspberry positioned on the product. The engineering design and implementation of a changeable production system is guided by a self-execution system that independently find amongst others esplanade workplaces.
The imparted competences to students and professionals are project management method SCRUM, customization of workflows by Industrie4.0 principles, the enhancements of products with new personalized intelligent parts, electrical and electronic selfprogrammed components and the control of access of the product memory information, to plan in a digital engineering environment and set up of the physical factory to produce customer orders. The gained action-orientated experience refers to the chances and requirements for holistic digital and physical systems.
In analog layout design, chip floorplans are usually still handcrafted by human experts. Particularly, the nondiscrete variability of block dimensions must be exploited thereby, which is a serious challenge for optimization-based algorithmic floorplanners. This paper presents a fundamentally new automation approach based on self-organization, in which floorplan blocks can autonomously move, rotate and deform themselves to jointly let compact results emerge from a synergistic flow of interaction. Our approach is able to minimize area and wirelength, supports nonslicing floorplan structures, can consider fully variable block dimensions, accounts for a fixed rectilinear boundary, and works absolutely deterministic. The approach is innovatively different from conventional, top-down oriented floorplanning algorithms.
Background and purpose: Transapical aortic valve replacement (TAVR) is a recent minimally invasive surgical treatment technique for elderly and high-risk patients with severe aortic stenosis. In this paper,a simple and accurate image-based method is introduced to aid the intra-operative guidance of TAVR procedure under 2-D X-ray fluoroscopy.
Methods: The proposed method fuses a 3-D aortic mesh model and anatomical valve landmarks with live 2-D fluoroscopic images. The 3-D aortic mesh model and landmarks are reconstructed from interventional X-ray C-arm CT system, and a target area for valve implantation is automatically estimated using these aortic mesh models.Based on template-based tracking approach, the overlay of visualized 3-D aortic mesh model, land-marks and target area of implantation is updated onto fluoroscopic images by approximating the aortic root motion from a pigtail catheter motion without contrast agent. Also, a rigid intensity-based registration algorithm is used to track continuously the aortic root motion in the presence of contrast agent.Furthermore, a sensorless tracking of the aortic valve prosthesis is provided to guide the physician to perform the appropriate placement of prosthesis into the estimated target area of implantation.
Results: Retrospective experiments were carried out on fifteen patient datasets from the clinical routine of the TAVR. The maximum displacement errors were less than 2.0 mm for both the dynamic overlay of aortic mesh models and image-based tracking of the prosthesis, and within the clinically accepted ranges. Moreover, high success rates of the proposed method were obtained above 91.0% for all tested patient datasets.
Conclusion: The results showed that the proposed method for computer-aided TAVR is potentially a helpful tool for physicians by automatically defining the accurate placement position of the prosthesis during the surgical procedure.
The acquisition of data for reality mining applications is a critical factor, since many mobile devices, e.g. smartphones, must be capable of capturing the required data. Otherwise, only a small target group would be able to use the reality mining application. In the course of a survey, we have identified smartphone features which might be relevant for various reality mining applications. The survey classifies these features and shows how the support of each feature has changed over the years by analyzing 143 smartphones released between 2004 and 2015. All analyzed devices can be ranked by their number of provided features. Furthermore, this paper deals with quality issues which have occurred during carrying out the survey.
Many organizations identified the opportunities of big data analytics to support the business with problem-specific insights through the exploitation of generated data. Socio-technical solutions are developed in big data projects to reach competitive advantage. Although these projects are aligned to specific business needs, common architectural challenges are not addressed in a comprehensive manner. Enterprise architecture management is a holistic approach to tackle the complex business and IT architecture. The transformation of an organization's EA is influenced by big data projects and their data-driven approach on all layers. To enable strategy oriented development of the EA it is essential to synchronize these projects supported by EA management. In
this paper, we conduct a systematic review of big data literature to analyze which requirements for the EA management discipline are proposed. Thereby, a broad overview about existing research is presented to facilitate a more detailed exploration and to foster the evolution o the EA management discipline.
For many companies, it is major international sporting events (in particular the Football World Cup or the Olympic Games) that constitute the ideal platform for the integration of their target group-specific marketing communication into an attractive sports environment. Sports event organizers sell exclusive marketing rights for their events to official sponsors, who, in return, acquire exclusive options to utilize the event for their own advertising purposes. Ambush marketing is the method used by companies that do not hold marketin rights to an event, but still use their marketing activities in diverse ways to establish a connection to it. There is still whidespread debate and confusion about the topic. Ambush marketing is often defined in different ways, by different people, according to their position as either supporters of opponents of the practice.
Reliable and accurate car driver head pose estimation is an important function for the next generation of advanced driver assistance systems that need to consider the driver state in their analysis. For optimal performance, head pose estimation needs to be non-invasive, calibration-free and accurate for varying driving and illumination conditions. In this pilot study we investigate a 3D head pose estimation system that automatically fits a statistical 3D face model to measurements of a driver’s face, acquired with a low-cost depth sensor on challenging real-world data. We evaluate the results of our sensor-independent, driver-adaptive approach to those of a state-of-the-art camera-based 2D face tracking system as well as a non-adaptive 3D model relative to own ground-truth data, and compare to other 3D benchmarks. We find large accuracy benefits of the adaptive 3D approach.
The fast moving process of digitization1 demands flexibility in order to adapt to rapidly changing business requirements and newly emerging business opportunities. New features have to be developed and deployed to the production environment a lot faster. To be able to cope with this increased velocity and pressure, a lot of software developing companies have switched to a Microservice Architecture (MSA) approach. Applications built this way consist of several fine-grained and heterogeneous services that are independently scalable and deployable. However, the technological and business architectural impacts of microservices based applications directly affect their integration into the digital enterprise architecture. As a consequence, traditional Enterprise Architecture Management (EAM) approaches are not able to handle the extreme distribution, diversity, and volatility of micro-granular systems and services. We are therefore researching mechanisms for dynamically integrating large amounts of microservices into an adaptable digital enterprise architecture.
The Internet of Things, enterprise social networks, adaptive case management, mobility systems, analytics for big data, and cloud services environments are emerging to support smart connected products and services and the digital transformation. Biological metaphors of living and adaptable ecosystems provide the logical foundation for self-optimizing and resilient run-time environments for intelligent business services and related distributed information systems with service-oriented enterprise architectures. We are investigating mechanisms for flexible adaptation and evolution for the next digital enterprise architecture systems in the context of the digital transformation. Our aim is to support flexibility and agile transformation for both business and related enterprise systems through adaptation and dynamical evolution of digital enterprise architectures. The present research paper investigates digital transformations of business and IT and integrates fundamental mappings between adaptable digital enterprise architectures and service-oriented information systems. We are putting a spotlight with the example domain – Internet of Things.
This paper addresses the turn-on switching process of insulated-gate bipolar transistor (IGBT) modules with anti-parallel free-wheeling diodes (FWD) used in inductive load switching power applications. An increase in efficiency, i.e. decrease in switching losses, calls for a fast switching process of the IGBT, but this commonly implies high values of the reverse-recovery current overshoot. To overcome this undesired behaviour, a solution was proposed which achieves an independent control of the collector current slope and peak reverse recovery current by applying a gate current that is briefly turned negative during the turn-on process. The feasibility of this approach has already been shown, however, a sophisticated control method is required for applying it in applications with varying currents, temperature and device parameters. In this paper a solution based on an adaptive, iterative closed-loop ontrol is proposed. Its effectiveness is demonstrated by experimental results from a 1200 V/200A IGBT power module for different load currents and reverse-recovery current overshoots.
The development of in vitro adipose tissue constructs is highly desired to cope with the increased demand for substitutes to replace damaged soft tissue after high graded burns, deformities or tumor removal. To achieve clinically relevant dimensions, vascularization of soft tissue constructs becomes inevitable but still poses a challenge. Adipose-derived stem cells (ASCs) represent a promising cell source for the setup of vascularized fatty tissue constructs as they can be differentiated into adipocytes and endothelial cells in vitro and are thereby available in sufficiently high cell numbers.
This review summarizes the currently known characteristics of ASCs and achievements in adipogenic and endothelial differentiation in vitro. Further, the interdependency of adipogenesis and angiogenesis based on the crosstalk of endothelial cells, stem cells and adipocytes is addressed at the molecular level. Finally, achievements and limitations of current co-culture conditions for the construction of vascularized adipose tissue are evaluated.
Um sich im Kommunikationswettbewerb zu profilieren und Streuverluste zu minimieren, bedienen sich Unternehmen vermehrt den sogenannten "nicht klassischen" Kommunikationsinstrumenten. Sponsoring stellt dabei einen erfolgsversprechenden Ansatz dar, da Sponsoring in einem attraktiven, emotional- aufgeladenen und nicht -kommerziellen Umfeld stattfindet. Aufgrund der zunehmenden Reizüberflutung der Konsumenten erscheint die Erreichung gesteckter Sponsoringziele durch bloße Sichtbarkeit jedoch nicht mehr zufriedenstellend realisierbar. Der vorliegende Beitrag behandelt das Thema Aktuelle Trends im Sponsoring im Sport. Die Analyse der aktuellen Entwicklungen zeigt, dass sich die Wirkungsvoraussetzungen des Sponsoring im Zeitverlauf verändert haben. Es bedarf neuer und innovativer Aktivierungsmaßmahmen, um die Reizüberflutung der Konsumenten zu überwinden und die Potentiale des Sponsorings zu nutzen. Die Darstellung praktischer Beispiele aus dem Sportmarketing zeigt, dass die handelnden Akteure die neuen Herausforderungen des Sponsorings erkannt haben. Es werden die aktuellen Entwicklungen hinsichtlich Digitalisierung, Internationalisierung, Professionalisierung und unkonventionaller Aktivierung aufgezeigt.
In dieser Ausarbeitung geht es um den aktuellen Stand der Digitalisierung der Textilindustrie. Sie dient als Grundlage zur Master-Thesis und soll die Frage beantworten, ob ein Informations-System, das die Textilprozesskette begleitet, benötigt wird. Dazu werden die einzelnen Prozessschritte kurz erläutert. In der Ausarbeitung wird auch die Verbindung zwischen der Textilindustrie und den neuen Möglichkeiten mit dem Internet der Dinge beleuchtet.
Bei großen Sportereignissen wie der diesjährigen Fußball- Europameisterschaft oder den Olympischen Sommerspielen 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 vorliegenden 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 Marktführer McDonald's Punkte zu sammeln.
Purpose: The purpose of this paper is to comprehensively characterise the interdisciplinary phenomenon of ambush marketing in sports, structure its manifestations, illustrate the consequences associated with ambush marketing and provide a critical evaluation from an objective perspective.
Design/methodology/approach: Various approaches to the definition of ambush marketing are presented and the objectives pursued with ambush marketing are identified. In this paper a new approach has been developed to structure the strategies and manifestations of ambush marketing.
Findings: It is a fine line between creative marketing and infringing on sponsorship rights. So the interdisciplinary phenomenon ambush marketing is discussed controversially. Ambush marketing is situated at the intersection of two opposing spheres of interest conducting a battle for shares of the marketing potential of a sports event. On one side there is the disparaging view of ambush marketing founded on legal and/or ethical considerations. On the other, the author has the respectful assessment of ambushers characterised by their innovative, creative marketing.
Practical implications: The analysis conducted in this paper leads to the conclusion that a general evaluation or condemnation of ambush marketing is not feasible. A four-field matrix emerges from the combination of a legal statutory consideration on one hand and an ethical-moral assessment on the other.
Originality/value: The paper describes and structures ambush marketing in a novel form and discusses illustrating examples from major sporting events. Ambush marketing is evaluated from a neutral perspective by summarising the opportunities and threats of ambush marketing which leads to a nuanced contemplation of ambush marketing.
A highly integrated synchronous buck converter with a predictive dead time control for input voltages >18 V with 10 MHz switching frequency is presented. A high resolution dead time of ˜125 ps allows to reduce dead time dependent losses without requiring body diode conduction to evaluate the dead time. High resolution is achieved by frequency compensated sampling of the switching node and by an 8 bit differential delay chain. Dead time parameters are derived in a comprehensive study of dead time depended losses. This way, the efficiency of fast switching DC-DC converters can be optimized by eliminating the body diode forward conduction losses, minimizing reverse recovery losses and by achieving zero voltage switching. High-speed circuit blocks for fast switching operation are presented including level shifter, gate driver, PWM generator. The converter has been implemented in a 180 nm high-voltage BiCMOS technology.
This paper presents an efficient implementation of a reconfigurable battery stack which allows full exploitation of the capacity of every single cell. Contrary to most other approaches, it is possible to electrically remove one or more cells from the battery stack. Therefore, the overall capacity of the system is not restricted by the weaker cells, and cells with very different states of health can be used, making the system very attractive for refurbished batteries. For the required switches, low-voltage high-current MOSFETs are used. A demonstrator has been built with a total capacity of up to 3.5 kWh, a nominal voltage of 35 V, and currents up 200 A.
This paper presents a laboratory experiment integrating the fields of electronics design, power electronics and drive control. The aim of this experiment is first to illustrate the need for a deep knowledge and the challenges in power electronics and its applications, in this particular case for drive control. The different tasks in this experiment are executed on a complete setup for a brushless dc motor test bench. The tasks assigned to the students are designed such that, in some tasks the knowledge from a particular field, power electronics, electronic design or drive control is deepened, whereas in other tasks the knowledge from more than one of these fields is needed to solve the given problem. Thus, the experiment trains students in the particular domains but illustrates as well the links between power electronics, electronic design and drive control.
This paper enhances SWARM, a novel deterministic analog layout automation approach based on the idea of cellular automata. SWARM implements a decentralized interaction model in which responsive layout modules, covering basic circuit types, autonomously move, rotate and deform themselves to let constraint-compliant, compact layout solutions emerge from a synergetic flow of self-organization. With the ability to consider design constraints both implicitly and explicitly, SWARM joins the layout quality of procedural generators with the flexibility of optimization algorithms, combining these two kinds of automation into a “bottom-up meets top-down” flow. The new enhancements are demonstrated in an OTA example, depicting the power of SWARM and its enormous potential for future developments.
To illustrate the power and the pitfalls of Bionic Optimization, we will show some examples spanning classes of applications and employing various strategies. These applications cover a broad range of engineering tasks. Nevertheless, there is no guarantee that our experiences and our examples will be sufficient to deal with all questions and issues in a comprehensive way. As general rule it might be stated, that for each class of problems, novices should begin with a learning phase. So, in this introductory phase, we use simple and quick examples, e.g., using small FE-models, linear load cases, short time intervals and simple material models. Here beginners within the Bionic Optimization community can learn which parameter combinations to use. In Sect. 3.3 we discuss strategies for optimization study acceleration. Making use of these parameters as starting points is one way to set the specific ranges, e.g., number of parents and kids, crossing, mutation radii and, numbers of generations. On the other hand, these trial runs will doubtless indicate that Bionic Optimization needs large numbers of individual designs, and considerable time and computing power. We recommend investing enough time preparing each task in order to avoid the frustration should large jobs fail after long calculation times.
Like many others, fashion companies have to deal with a global and very competitive environment. Thus companies rely on accurate sales forecasts - as key success factor of an efficient supply chain management. However, forecasters have to take into account some specificities of the fashion industry. To respond to these constraints, a variety of different forecasting methods exists, including new, computer-based predictive analytics. After the evaluation of different methods, their application to the fashion industry is investigated through semi structured expert interviews. Despite several benefits predictive analytics is not yet frequently used in practice. This research does not only reflect an industry profile, but also gives important insights about the future potential and obstacles of predictive analytics.
Application to CAE systems
(2016)
Due to the broad acceptance of CAD-systems based on 3D solids, the geometric data of all common CAE (Computer-Aided Engineering) software, at least in mechanical engineering, are based on these solids. We use solid models, where the space filled by material is defined in a simple and easily useable way. Solid models allow for the development of automated meshers that transform solid volumes into finite elements. Even after some unacceptable initial trials, users are able to generate meshes of non-trivial geometries within minutes to hours, instead of days or weeks. Once meshing had no longer been the cost limiting factor of finite element studies, numerical simulation became a tool for smaller industries as well.
Due to the broad acceptance of CAD-systems based on 3D solids , the geometric data of all common CAE (Computer-Aided Engineering) software, at least in mechanical engineering, are based on these solids. We use solid models , where the space filled by material is defined in a simple and easily useable way. Solid models allow for the development of automated meshers that transform solid volumes into finite elements. Even after some unacceptable initial trials, users are able to generate meshes of non-trivial geometries within minutes to hours, instead of days or weeks. Once meshing had no longer been the cost limiting factor of finite element studies, numerical simulation became a tool for smaller industries as well.
In the early days of automated meshing development, there were discussions over the use of tetragonal (Fig. 4.1) or hexagonal based meshes. But, after a short period of time, it became evident, that there were and will always be many problems using automated meshers to generate hexagonal elements . So today nearly all automated 3D-meshing systems use tetragonal elements .
The evolution of Services Oriented Architectures (SOA) presents many challenges due to their complex, dynamic and heterogeneous nature. We describe how SOA design principles can facilitate SOA evolvability and examine several approaches to support SOA evolution. SOA evolution approaches can be classified based on the level of granularity they address, namely, service code level, service interaction level and model level. We also discuss emerging trends, such as microservices and knowledge-based support, which can enhance the evolution of future SOA systems.
The digitization of our society changes the way we live, work, learn, communicate, and collaborate. The Internet of Things, enterprise social networks, adaptive case management, mobility systems, analytics for big data, and cloud services environments are emerging to support smart connected products and services and the digital transformation. Biological metaphors of living and adaptable ecosystems provide the logical foundation for self-optimizing and resilient run-time environments for intelligent business services and service-oriented enterprise architectures. Our aim is to support flexibility and agile transformations for both business domains and related information technology. The present research paper investigates mechanisms for decision analytics in the context of multi-perspective explorations of enterprise services and their digital enterprise architectures by extending original architecture reference models with state of art elements for agile architectural engineering for the digitization and collaborative architectural decision support. The paper’s context focuses on digital transformations of business and IT and integrates fundamental mappings between adaptable digital enterprise architectures and service-oriented information systems. We are putting a spotlight on the example domain – Internet of Things.
Data collected from internet applications are mainly stored in the form of transactions. All transactions of one user form a sequence, which shows the user´s behaviour on the site. Nowadays, it is important to be able to classify the behaviour in real time for various reasons: e.g. to increase conversion rate of customers while they are in the store or to prevent fraudulent transactions before they are placed. However, this is difficult due to the complex structure of the data sequences (i.e. a mix of categorical and continuous data types, constant data updates) and the large amounts of data that are stored. Therefore, this thesis studies the classification of complex data sequences. It surveys the fields of time series analysis (temporal data mining), sequence data mining or standard classification algorithms. It turns out that these algorithms are either difficult to be applied on data sequences or do not deliver a classification: Time series need a predefined model and are not able to handle complex data types; sequence classification algorithms such as the apriori algorithm family are not able to utilize the time aspect of the data. The strengths and weaknesses of the candidate algorithms are identified and used to build a new approach to solve the problem of classification of complex data sequences. The problem is thereby solved by a two-step process. First, feature construction is used to create and discover suitable features in a training phase. Then, the blueprints of the discovered features are used in a formula during the classification phase to perform the real time classification. The features are constructed by combining and aggregating the original data over the span of the sequence including the elapsed time by using a calculated time axis. Additionally, a combination of features and feature selection are used to simplify complex data types. This allows catching behavioural patterns that occur in the course of time. This new proposed approach combines techniques from several research fields. Part of the algorithm originates from the field of feature construction and is used to reveal behaviour over time and express this behaviour in the form of features. A combination of the features is used to highlight relations between them. The blueprints of these features can then be used to achieve classification in real time on an incoming data stream. An automated framework is presented that allows the features to adapt iteratively to a change in underlying patterns in the data stream. This core feature of the presented work is achieved by separating the feature application step from the computational costly feature construction step and by iteratively restarting the feature construction step on the new incoming data. The algorithm and the corresponding models are described in detail as well as applied to three case studies (customer churn prediction, bot detection in computer games, credit card fraud detection). The case studies show that the proposed algorithm is able to find distinctive information in data sequences and use it effectively for classification tasks. The promising results indicate that the suggested approach can be applied to a wide range of other application areas that incorporate data sequences.
It is assumed that more education leads to better understanding of complex systems. Some researchers claim, 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 (Booth Sweeney and Sterman 2000). 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 (Booth Sweeney and Sterman 2000) 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 seem to lose the capability of dealing with simple SF tasks from domains other than their field. We thus find hints on déformation professionelle in higher education.
Sportmarketing ist die spezifische Anwendung der Marketing-Prinzipien und -Prozesse auf Sportprodukte und Sportdienstleistungen im Sinne der marktorientierten Unternehmensführung. Die Prinzipien des allgemeinen Marketing können allerdings nicht ohne weiteres auf den Sport übertragen werden. Vielmehr wird ein eigenständiger Ansatz benötigt, wenn anstelle von klassischen Produkten oder Dienstleistungen der Sport ins Zentrum der Betrachtung rückt. Ein zentrales Unterscheidungsmerkmal zwischen Sportmarketing und klassischem Marketing ist der Kunde. Sportfans unterscheiden sich in vielerlei Hinsicht fundamental von Konsumenten normaler Produkte, worauf im vorliegenden Beitrag eingegangen wird.
Aufgrund seiner hohen gesellschaftlichen Bedeutung, der emotionalen Strahlkraft und der überdurchschnittlich hohen medialen Reichweiten hat sich der Sport zu einer der bedeutendsten Kommunikationsplattformen entwickelt. Unternehmen nutzen Sportsponsoring, um ihre Bekanntheit im hochemotionalen Umfeld des Sports zu steigern sowie Produkte und Marken mittels eines Imagetransfers zu profilieren. Sportsponsoring bietet eine attraktive Möglichkeit, den heutigen kommunikationspolitischen Problemstellungen des steigenden Werbedrucks, der erhöhten Reizüberflutung und der sinkenden Effizienz klassischer Kommunikationsinstrumente entgegenzutreten.
Im vorliegenden Beitrag werden Best Practice Beispiele der wichtigsten Organisationsformen des Sponsoring anhand eines eigens entwickelten Untersuchungsdesigns analysiert. Die Fallbeispiele zeigen, dass die Erreichung anvisierter Sponsoringziele von internen und externen Einflussfaktoren abhängig gemacht werden kann. Während die bloße Sichtbarkeit eines Sponsorships alleine nicht zielführend ist, geht es vielmehr darum, die Sponsoringpartnerschaft durch systematische Aktivierungskonzepte und eine ganzheitliche Integration bekannt zu machen. Die untersuchten Fallbeispiele liefern kreative Lösungsansätze und lassen Rückschlüsse auf Erfolgsfaktoren des Sportsponsoring zu.
The book provides suggestions on how to start using bionic optimization methods, including pseudo-code examples of each of the important approaches and outlines of how to improve them. The most efficient methods for accelerating the studies are discussed. These include the selection of size and generations of a study’s parameters, modification of these driving parameters, switching to gradient methods when approaching local maxima, and the use of parallel working hardware.
Bionic optimization means finding the best solution to a problem using methods found in nature. As evolutionary strategies and particle swarm optimization seem to be the most important methods for structural optimization, we primarily focus on them. Other methods such as neural nets or ant colonies are more suited to control or process studies, so their basic ideas are outlined in order to motivate readers to start using them.
A set of sample applications shows how bionic optimization works in practice. From academic studies on simple frames made of rods to earthquake-resistant buildings, readers follow the lessons learned, difficulties encountered and effective strategies for overcoming them. For the problem of tuned mass dampers, which play an important role in dynamic control, changing the goal and restrictions paves the way for multi-objective-optimization. As most structural designers today use commercial software such as FE-Codes or CAE systems with integrated simulation modules, ways of integrating bionic optimization into these software packages are outlined and examples of typical systems and typical optimization approaches are presented.
The closing section focuses on an overview and outlook on reliable and robust as well as on multi-objective optimization, including discussions of current and upcoming research topics in the field concerning a unified theory for handling stochastic design processes.
In this chapter we introduce methods to improve mechanical designs by bionic methods. In most cases we assume that a general idea of the part or system is given by a set of data or parameters. Our task is to modify these free parameters so that a given goal or objective is optimized without violation of any of the existing restrictions.
Mit dem Betrieb von KWK-Anlagen lässt sich nennenswert Primärenergie einsparen. KWK-Anlagen werden aus diesem Grund aufgrund verschiedener Gesetze und Richtlinien gefördert. Zum wirtschaftlichen Betrieb einer KWK-Anlage ist es erforderlich, den größtmöglichen Teil des erzeugten elektrischen Stroms entweder selbst zu verbrauchen oder an Dritte (Mieter, Wohnungseigentümer…) zu verkaufen. Mit dem KWKG 2016 werden größere KWK-Anlagen interessant, und Anlagen mit geringerer jährlicher Laufzeit können sich sogar wirtschaftlicher darstellen als reine Grundlastanlagen.
Blood vessel reconstruction is still an elusive goal for the development of in vitro models as well as artificial vascular grafts. In this study, we used a novel photo curable cytocompatible polyacrylate material (PA) for freeform generation of synthetic vessels. We applied stereolithography for the fabrication of arbitrary 3D tubular structures with total dimensions in the centimeter range, 300 µm wall thickness, inner diameters of 1 to 2 mm and defined pores with a constant diameter of approximately 100 µm or 200 µm. We established a rinsing protocol to remove remaining cytotoxic substances from the photo-cured PA and applied thio-modified heparin and RGDC-peptides to functionalize the PA surface for enhanced endothelial cell adhesion. A rotating seeding procedure was introduced to ensure homogenous endothelial monolayer formation at the inner luminal tube wall. We showed that endothelial cells stayed viable and adherent and aligned along the medium flow under fluid-flow conditions comparable to native capillaries. The combined technology approach comprising of freeform additive manufacturing (AM), biomimetic design, cytocompatible materials which are applicable to AM, and biofunctionalization of AM constructs has been introduced as BioRap® technology by the authors.
Size and cost of a boost converter can be minimized by reducing the voltage overshoot and fastening the transient response in case of load transient. The presented technique improves the transient response of a current mode controlled boost converter, which usually suffers from bandwidth limitation because of its right-half-plane zero (RHPZ). The proposed technique comprises a load current estimation which works as part of a digital controller without any additional measurements. Based on the latest load estimation the controller parameters are adapted, achieving small voltage overshoot and fast transient response. The presented technique was implemented in a digital control circuit, consisting of an ASIC in a 110 nm-technology, a Xilinx Spartan-6 field programmable gate array (FPGA), and a TI-ADS8422 analog to-digital-converter (ADC). Simulation and measurements of a 4V-to-6.3V, 500mA boost converter show an improvement of 50% in voltage overshoot and response time to load transient.
Branding in sports
(2016)
Brands are ubiquitous in the sports business. The significance of the brand is fuelled not only by the various functions that a brand performs for providers and consumers in sports, but by the monetary value that brands have come to represent for sporting organizations. As part of the commercialization and professionalization of sports, a uniform brand presence is becoming increasingly important for sporting organizations. The implication is the need for systematic and integral brand management. This chapter initially examines the key features of sports from the marketing perspective and the most important fundamentals of sport marketing. Based on this, we will demonstrate specifically how brands in sports are established and cultivated.