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Arts'Codes: A New Methodology for the Development of Real-Time Embedded Applications for Control SystemsTeitelbaum, Aryeh Roberto, a_hay@jct.ac.il January 2007 (has links)
Embedded real-time applications have to allow interaction between the control computer and the controlled environment. Controlling the environment requires in particular to take into account its time constraints and critical logical conditions. One of the main programmer efforts in real-time application's development is to trace the incoming events, and to perform reactions based on the current system status, according to the application requirements. All this have to be handled, although external events may come in the middle of a critical reaction, which may disturb it. This problem involves two difficulties: X The cognitive efforts to percept the problem, and consequently to express the solution. X The correct translation of this solution to code. Two requirements were defined in this research in order to achieve high-quality performance: clearness and robustness, clearness in the design, and robustness in the execution. In this work the author proposes a methodology and a tool for real-time application's development that uses or implies an innovated form of design based on natural-cognitive researches. This design method has clear compilation's rules to produce an Object-Oriented light-code, suitable for embedded platforms. These compilation's rules introduce to the code implicit security and synchronization's elements, to support robust execution. In this methodology, clear development phases were defined, using a high-degree of reuse and even polymorphism, which were emphasized in the research. Several existing ideas were improved/adapted and synthesized together with the author's innovation, creating the Arts'Codes method for real-time application development. The work includes cognitive evaluations, assuring the natural skills of the design. Arts'Codes method proposes a natural VPL (Visual Programming Language) for real-time applications, based on hierarchic components. This VPL is built on a minimum of diagrams: one for the static architecture and one for the dynamic behaviour, with a similar restricted notation at all levels. These two diagrams (static architecture and dynamic behaviour) are interleaved in a unified view. This method was implemented by building a suitable graphic editor, which automatically compiles the applications diagrams in a light and robust Object-Oriented code (based on Parallel Automata FSM), and by building an execution compact software platform. Furthermore, the parallel automata FSM are translated automatically in PTL temporal formula defining the goals and the behaviours of the components, permitting to prove a-priory that the components behaviours are consistent to their goals. The execution platform is based on a restricted implementation of the synchrony hypothesis and on a powerful model of execution: the parallel automata FSM. These Parallel Automata describe the dynamic behaviours of the components and allows implementing run-time exceptions handling too. In addition, the research proposes a tri-processor execution hardware platform, which supports a hybrid synchronous/multi-threading execution. This method will contribute to versatile, clear and robust real-time application's development.
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Model-Based Hazard Analysis of Undesirable Environmental and Components InteractionMehrpouyan, Hoda January 2011 (has links)
Identifying the detrimental effect of environmental factors and subsystem interactions are one of themost challenging aspects of early hazard assessment in the design of complex safety critical systems.Therefore, a complete understanding of potential failure effects before the catastrophe happens is a verydifficult task. The thesis proposes a model-based hazard analysis procedure for early identification ofpotential safety issues caused by unexpected environmental factors and subsystem interactions within acomplex safety critical system. The proposed methodology maps hazard and vulnerability modes tospecific components in the system and analyzes the hazard propagation paths for risk control andprotection strategies. The main advantage of the proposed method is the ability to provide the designerswith means to use low-fidelity, high level models to identify hazardous interactions. Using thistechnique, designers can examine the collective impacts of environmental and subsystem risks onoverall system during early stages of design and develop a hazard mitigation strategy.
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Design kadeřnického křesla / Design of armchair for hairdressingNečasová, Barbora January 2008 (has links)
This thesis aims to design a modern innovative hairdresser chair. The main innovation of the proposal is seen in the new interior arrangement with a washing component as a central point. The main idea of the whole work is to design such a hairdresser chair that would supersede all other chairs normally used in hairdressing salons. All activities concerned with the hair care (washing, trimming, colouring etc.) would be done on a sole chair that would be in the case of need placed to the washing component. By reclining the chair backrest and turning the washing component a client’s hair could be easily washed (or other functions that need water tap could be done). There are several advantages within this proposal. Primarily it offers fewer chairs in hair dressing salon as well as a more variable interior. Another positive feature is that the washing component can be used more economically when it serves to more seats. Finally, the visual aspect and shape interconnection of two basic components - washing basin and hairdresser’s chair - are innovative.
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Representing Design Patterns As Super Components In Component Oriented Software EngineeringAvkarogullari, Okan 01 February 2004 (has links) (PDF)
It is widely believed and empirically shown that component reuse improves both the quality and productivity of software development. This brings the necessity of a graphical editor to model the projects by using components. A graphical editor was implemented for the development of Component Oriented software development. The editor facilitates modeling efforts through application of the graphical modeling language COSEML. Both design patterns and software components have come to play important roles in software development. The correlation between software components and design patterns is apparent. In the design phase of the projects design patterns are used widely both in component and object oriented projects. Design patterns can be used as super components in component-based development . Software reuse, software components, design patterns, use of design patterns in component-based development, and component architectures are studied in details to address the need for the approach. COSE modeling activity starts with the decomposition of the target system into building blocks in a top-down order. Next, interfaces between these blocks are defined. If required design patterns can be added to model as super components.
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Development And Investigation of Two-Stage Silica Gel + Water Adsorption Cooling Cum Desalination SystemMitra, Sourav January 2016 (has links) (PDF)
The present research work caters to two important needs of rural India: i) desalination of subsoil/coastal brackish water and ii) basic refrigeration for short term preservations of agro-produce, medicines etc. Fortunately, such places are blessed with abundant solar insolation and/or low grade thermal energy (< 100°C) is available which may be tapped for this purpose instead of relying solely on grid electricity. Both the objectives of desalination and cooling are realized by evaporating brackish water at a low pressure (~1 kPa) and thermally compressing the water vapour to a higher pressure before condensing it. Adsorption route is chosen for compression where silica gel is the adsorbent and water to be desalinated as the refrigerant. The objective of this study is to develop a laboratory prototype of a two-stage adsorption cooling cum desalination system driven by low grade heat source. The entire system is air-cooled which is necessitated by non-availability of heat exchange grade cooling water.
Initially various experimental and theoretical studies are carried out for characterizing silica gel + water pair which is fundamental to the system design. RD type silica gel is used in this study due to its high uptake capabilities. The uptakes for this adsorption pair at various pressure and temperature conditions are measured using a specially designed isothermal adsorber cell connected to an evaporator. Subsequently, a modelling study of adsorption kinetics is performed for a monolayer of silica gel in order to estimate the adsorption time scale. This time scale is used as an input for the scaling analysis of columnar packed silica gel bed. The scaling analysis showed that the thermal diffusion time scale limits the adsorption process. It also showed that for a given thermal length scale, the bed has a unique vapour flow length scale beyond which the adsorption phenomenon gets limited due to pressure drop. The scaling results are validated by simulation studies.
A shell-and-tube heat exchanger is chosen for the adsorber which closely mimics the columnar silica gel packing studied in scaling analysis. The heat exchanger is designed for radial entry of vapour. A modelling study is performed on ANSYS® Fluent platform for optimising the tube pitch by minimising the overall thermal capacitance of the bed. The shell diameter is determined for this tube pitch based on the vapour flow length criterion established through scaling. To experimentally study the effect of pressure drop on bed performance, the radial entry of vapour is closed for 1 bed/stage (out of the 4 beds/stage) enforcing the vapour to flow along the longer axial dimension.
The system is generously instrumented for precise measurements and control over the various experimental parameters. For the functioning of the adsorber system, various vapour valves and water (heat transfer fluid) valves need to be operated in a cyclical and synchronized manner. Individual components are fitted with pressure, temperature and water flow sensors. The entire operation and data acquisition for the adsorption system has been automated using National Instruments® (NI) PXIe controller executing an in-house developed code written on NI Labview® platform. To simulate solar/waste heat input, multiple electrical heaters are used in this study and a constant temperature bath is used to simulate the cooling load at the evaporator.
Prior to conducting experiments a 4-bed lumped dynamic model is developed based on the design data of the system to simulate the two-stage system performance for various input conditions. The study helped to optimise the performance of a two-stage system. The study also compares the two-stage and single-stage system performance for various ambient temperatures (25–40°C). The study revealed that for pressure lifts higher than 5 kPa a two-stage system is preferable.
A detailed experimental study is conducted on the developed prototype by operating it in various conditions namely 2, 3 and 4–bed modes for single and two-stage operations; with 1.0–1.7 kPa evaporator pressures, half cycle time varying between 1200–3000s and source temperature in the range of 75–85°C. The system is operated indoors during summer conditions wherein the ambient temperature is found to be 36±1°C which is significantly higher than the design point of 25°C. This resulted in lower than expected throughput; however, the system performance variation is qualitatively similar to as predicted by the lumped model. A comparison between the experimental and simulated bed temperature revealed that the thermal wave during the switching of hot/cold water plays a significant role causing a large deviation from the simulation results. A comparative study is carried out between the beds with radial vapour flow to that with axial flow and the results validate the scaling criterion. Experimental results also depict that two-stage operation is favourable when the pressure lift required is larger than 5 kPa. Such large pressure lift is encountered when air-cooling is used in a tropical country like India.
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Additive Fertigung frei geformter Betonbauteile durch selektives Binden mit calciumsilikatbasierten ZementenWeger, Daniel, Talke, Daniel, Lowke, Dirk, Henke, Klaudius, Gehlen, Christoph, Winter, Stefan 21 July 2022 (has links)
Die additive Fertigung erlaubt ein bisher nicht gekanntes Maß an geometrischer Freiheit bei der Gestaltung von Bauteilen. In der Medizin- und Dentaltechnik wird die additive Fertigung beispielsweise eingesetzt, um an die individuelle Anatomie des Patienten angepasste Prothesen und Implantate herzustellen. Im Maschinenwesen ermöglicht sie den Bau von multifunktionalen und formoptimierten Bauteilen und damit eine Senkung des Materialeinsatzes bei gleichzeitiger Steigerung der Leistungsfähigkeit. In der Luft- und Raumfahrttechnik wird sie genutzt, um mittels Topologieoptimierung oder durch das Zusammenfassen von ganzen Baugruppen zu einem einzelnen Bauteil Gewicht zu sparen [1]. (Aus: Motivation] / Additive manufacturing allows a previously unknown degree of geometric freedom in the design of components. In medical and dental technology for example, additive manufacturing is used to produce prostheses and implants adapted to the individual anatomy of the patient. In mechanical engineering, it enables the construction of multifunctional and shape-optimized components thus reducing the amount of material used while simultaneously increasing performance. In aerospace engineering, it is used to save weight by means of topology optimization or by combining entire assemblies into a single component [1]. [Off: Motivation]
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Assisting decision making in component design for sustainable manufacturingEastlick, Dane, 1985- 15 March 2012 (has links)
Current life cycle assessment tools are often deficient in assisting design for sustainable manufacturing efforts. Integrating an improved assessment method into a decision support framework will provide a means for designers and engineers to better understand the impacts of their decisions. A unit process modeling-based sustainability assessment method is presented to assist design decision making by accounting for and quantifying economic, environmental, and social attributes. A set of these sustainability metrics is defined as a basis for comparison of component design alternatives. The method is demonstrated using two titanium component production alternatives that represent typical design for manufacturing scenarios. The modeling method significantly increases the resolution of sustainable manufacturing metrics over conventional assessment techniques, and is one aspect of the overall decision support framework developed. Additionally, fixed sum importance weighting, weighted sum modeling, and scenario analysis were selected as easily employed and transparent design decision techniques to provide the remaining elements of the framework. The demonstration of the decision support framework for titanium component manufacturing illustrates that the sequential approach developed can assist engineers in developing more sustainable components and products. / Graduation date: 2012
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Advancing the Filling Process in Agricultural Machinery : Hopper observation technology for improved filling in Väderstad´s Seed Hawk 600-900C / Förbättring av fyllningsprocessen i jordbruksmaskiner : Övervakningssystem av sålådor för bättre påfyllning av Väderstads Seed Hawk 600-900CAbou Shkair, Ali, Augustini, Jakob January 2024 (has links)
This master’s thesis was conducted in the spring of 2024 at Väderstad AB, a companyknown for producing high-performance agricultural machines, such as seeding machines. Among these machines, the Seed Hawk 600-900C is an important machine for thecompany’s future. The innovation department at Väderstad has developed an automatic Bag Slicer, capable of slicing large bags of seeds/fertilizer without requiring the farmer to climb onto the machine, a cumbersome and hazardous task. Several challenges arisein integrating the Bag Slicer onto their machines, which has hindered its implementation.These challenges have been thoroughly investigated, and one has been selected as thepriority for resolution: enabling the observation of the filling process without the need for climbing onto the hopper. To address this challenge, theoretical studies, concept development, and investigations in the 3D software Blender have been conducted. Creo Parametric was utilized to assemble the Bag Slicer onto the Seed Hawk machine and design other essential components. Coloring, animations, and renderings were created in Blender to create a configuration of cameras, lights, cables, and investigate their properties. This configuration provides users witha comprehensive overview of the filling process and enables operation of the Bag Slicerin the field from the safety of a tractor or wheel loader. Consideration has been given to the conditions occurring inside and around the Seed Hawk machine when specifyingall the different components and operational requirements. The entire configuration was compiled into a complete list of specifications, constituting the main result of this thesis.
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