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Design Task (design + task)
Selected AbstractsSpatial Information: Classification and Applications in Building DesignCOMPUTER-AIDED CIVIL AND INFRASTRUCTURE ENGINEERING, Issue 4 2002Tang-Hung Nguyen Physical properties of building components are usually represented in building data models by their three-dimensional geometry and topology,also called spatial information. While geometric data of building components can be manipulated and managed by a computer-aided design (CAD) interface, their spatial relations (or topological information) are conventionally represented in a manual fashion into data models. The manual data representation, however, is inherently a complex and challenging task due to the wide variety of spatial relationships. Thus, topological information should be classified and modeled in such a way that the required spatial data for a particular design task can be automatically retrieved. This paper attempts to identify and classify various topological information commonly used in building design and construction into more specific categories (e.g., adjacency, connection, containment, separation, and intersection) to support automatic deduction of the spatial information in a computer-based building design system. The paper also discusses typical applications of the topological relations to different design activities. Finally, the development of deduction algorithms and the proposed building design system are briefly described. [source] Managing Complexity: The Executive MBA at the Zollverein SchoolDESIGN MANAGEMENT REVIEW, Issue 3 2007Andrej Kupetz President In this new and innovative program, management is viewed as a design task that engages the creative disciplines, as well as traditional skills in business and engineering. Andrej Kupetz, with students Martin Mangold and Miriam Selbeck, summarize the interdisciplinary nature of the curriculum, as well as its merging of theory and practice, and illustrate outcomes with the discussion of two real-world thesis projects. [source] Reduced pole placement method for cascaded frequency control via dispersed pulse invertersEUROPEAN TRANSACTIONS ON ELECTRICAL POWER, Issue 4 2005J. Sachau Abstract For modular power systems, structures with parallel power inverters are favourable in view of both easy expandability and supply security. The inverters' embedded controllers are implementing voltage and frequency droops and the superimposed frequency control is coupled via fieldbus. This is a case where a superimposed control is acting via one or more locally dispersed subimposed control-loops. As the states of the subimposed loops are inaccessible, their feedback is no longer viable. The method of reduced pole placement allows reformulation of the design task as complete state feedback without employing a feedback of the single virtual state that just globally describes the one or more subimposed systems. Results are presented for a robust grid frequency controller acting via dispersed pulse inverters. Copyright © 2005 John Wiley & Sons, Ltd. [source] Applying the proximity compatibility and the control-display compatibility principles to engineering design interfacesHUMAN FACTORS AND ERGONOMICS IN MANUFACTURING & SERVICE INDUSTRIES, Issue 1 2006Ling Rothrock The authors determine the utility of applying two display design principles toward the development of interfaces for engineering design. The first principle, called the Proximity Compatibility Principle, specifies that displays relevant to a common task or mental operation should be rendered close together in perceptual space. The second principle, called the Control-Display Compatibility Principle, stipulates that the spatial arrangement and manipulation of controls should be easily distinguishable. To examine the utility of both principles, the authors conducted an experiment comparing the ability of subjects to find effective designs using a separable versus a configural interface in a multi-objective engineering design task. Results suggest that the proximity compatibility principle is an effective indicator of task performance. Moreover, the control-display compatibility principle can be used as an indicator of performance efficiency. © 2006 Wiley Periodicals, Inc. Hum Factors Man 16: 61,81, 2006. [source] Designing globally optimal delta,sigma modulator topologies via signomial programmingINTERNATIONAL JOURNAL OF CIRCUIT THEORY AND APPLICATIONS, Issue 3 2009Yuen-Hong Alvin Ho Abstract We present a design methodology for globally optimizing the topologies of delta,sigma modulators (DSMs). Previous work cast the design task into a general non-convex, nonlinear programming problem, whereas we propose to recast it as a signomial programming problem. Convexification strategies are presented for transforming the signomial programming problem into its equivalent convex counterpart, thereby enabling the solution of globally optimal design parameters. It is also possible to include circuit non-ideal effects that affect the transfer function of the modulator into the formulation without affecting the computational efficiency. The proposed framework has been applied to topology synthesis problems of single-loop and multi-loop low-pass DSMs based on discrete-time circuitry. Numerical results confirm the effectiveness of the proposed approach over conventional nonlinear programming techniques. Copyright © 2008 John Wiley & Sons, Ltd. [source] Ausstattung von Klassenräumen mit Einrichtungen zum Temperieren, Lüften und BelichtenBAUPHYSIK, Issue 3 2009Gruppenleiterin Raumklimaqualität Runa Tabea Hellwig Dr.-Ing. Bauphysik allgemein; Energieeinsparung Abstract Fast alle Schulräume werden in Deutschland ausschließlich über Fenster mit Außenluft versorgt. Messungen haben gezeigt, dass die Belüftung der Schulräume vor allem in der kalten Jahreszeit unzureichend ist. Hybride Lüftungssysteme mit einer automatischen Unterstützung der Fensterlüftung könnten eine Möglichkeit bieten, die Häufigkeit schlechter Innenluftqualität in Schulen zu minimieren. Hierbei ist die Anordnung der dezentralen Zuluftöffnungen in den Fassaden eine der kritischsten Systemkomponenten, und es besteht gerade bei Schulgebäuden weiterer Untersuchungs- und Optimierungsbedarf. Im Rahmen des vom Bundesministerium für Wirtschaft und Technologie geförderten Verbund- projektes "Heizenergieeinsparung, thermische Behaglichkeit und gute Luftqualität in Schulgebäuden durch hybride Lüftungstechnik" werden die Eigenschaften von Klassenräumen im Landkreis Miesbach bezüglich der Temperierung, Belüftung und Belichtung aufgenommen. Die Begehung von 22 Schulen im Landkreis Miesbach ermöglicht für einen gesamten Landkreis die Bewertung der baulichen Gegebenheiten, welche die raumklimatischen Verhältnisse entscheidend beeinflussen. Die Belegungsdichte der Klassenräume im Landkreis Miesbach ist eher als normal bis gering einzustufen, da in ca. 80 % der Räume der Mindestwert von 2 m2 je Schüler eingehalten wird. 88 % der untersuchten Räume weisen eine mittlere bis hohe thermische Masse auf. Die meisten Klassenräume im Landkreis haben einen Fensterflächenanteil von 30 bis 60 %. Etwa 50 % der Räume besitzen keinen Sonnenschutz. Der bauliche sommerliche Wärmeschutz muss überwiegend als unzureichend bewertet werden. Etwa zwei Drittel der Klassenräume weisen eine gute bis mittlere Tageslichtversorgung auf. Die Klassenräume werden über Fenster belüftet. Die Fassaden besitzen vielfältige Öffnungsmöglichkeiten, wobei Drehkippflügel und Schwingflügel am häufigsten angetroffen werden. Equipment of classrooms with systems for maintaining temperature, for ventilation and for illumination. Most German classrooms are not equipped with mechanical ventilation systems. Natural ventilation controlled by the occupants opening the windows is the main way to provide fresh air. Measurements in real classrooms showed that the ventilation especially in cold season is insufficient. Hydrid ventilation systems with automatically controlled windows might reduce the prevalence of high carbon dioxide concentration inside the classrooms. The position of the air supply opening in the façade is the most sensible design task. There is still a big potential for optimization. In the frame of the project "Energy saving, thermal comfort and good indoor air quality in schools using hybrid ventilation" supported by the German Federal Ministry for Economic Affairs and Technology the properties of classrooms in the county Miesbach/Germany regarding thermal comfort, ventilation and illumination were collected. In sum data of 106 classrooms in 22 schools were collected. The density of persons is normal to low. Approximately 80% of the rooms offer at least 2 or more square meter per pupil. 88% of the investigated classrooms are built with medium or high thermal mass. The glazed facade area is between 30 and 60% for most of the classrooms. 50% of the classrooms do not have any sun shading device. The summer overheating protection by passive means is insufficient. Two thirds of the classrooms offer a good to acceptable daylight condition. The classrooms are ventilated by opening the windows. There are different opening types of the windows and several combinations of the types in the façades. Tilt and turn windows and the horizontally pivot-hung type are the most prevalent types. [source] Investigating static and dynamic characteristics of electromechanical actuators (EMA) with MATLAB GUIsCOMPUTER APPLICATIONS IN ENGINEERING EDUCATION, Issue 2 2010Gursel Sefkat Abstract This paper deals with the design of an electromechanical device considering some prescribed performance requirements, and static and dynamic analysis of this device are carried out. In studying the transient response of such a system, as part of dynamic analysis, two methods mostly used finite element method (FEM) and finite differences method (FDM). However, these methods need much CPU time. In this work, a computer simulator program is developed for an EMA. This technique is implemented in the MATLAB-Simulink environment and tested for different design tasks such as electromagnetic valves or electromechanical brakes etc. Furthermore, by using GUIDE tools within MATLAB, a simple useful and user-friendly GUI structure is developed to provide a visual approach to design and analysis process. © 2009 Wiley Periodicals, Inc. Comput Appl Eng Educ 18: 383,396, 2010; Published online in Wiley InterScience (www.interscience.wiley.com); DOI 10.1002/cae.20279 [source] Analog circuit design by nonconvex polynomial optimization: Two design examplesINTERNATIONAL JOURNAL OF CIRCUIT THEORY AND APPLICATIONS, Issue 1 2010Siu-Hong Lui Abstract We present a framework for synthesizing low-power analog circuits through global optimization over generally nonconvex multivariate polynomial objective function and constraints. Specifically, a nonconvex optimization problem is formed, which is then efficiently solved through convex programming techniques based on linear matrix inequality (LMI) relaxation. The framework allows both polynomial inequality and equality constraints, thereby facilitating more accurate device modelings and parameter tuning. Compared to traditional nonlinear programming (NLP), the proposed methodology exhibits superior computational efficiency, and guarantees convergence to a globally optimal solution. As in other physical design tasks, circuit knowledge and insight are critical for initial problem formulation, while the nonconvex optimization machinery provides a versatile tool and systematic way to locate the optimal parameters meeting design specifications. Two circuit design examples are given, namely, a nested transconductance(Gm),capacitance compensation (NGCC) amplifier and a delta,sigma (,,) analog-to-digital converter (ADC), both of them being the key components in many electronic systems. Copyright © 2008 John Wiley & Sons, Ltd. [source] | ||||||||||