Дисертації: "Design of devices"

1

Lee, Gregory S. "Low power haptic devices : ramifications on perception and device design /." Thesis, Connect to this title online; UW restricted, 2004. http://hdl.handle.net/1773/5863.

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2

ODSTAM, MÅNS, and ERNDAL A. N. D. R. E. A. S. STJ. "Game Design for Mobile Devices." Thesis, KTH, Skolan för datavetenskap och kommunikation (CSC), 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-134941.

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In the last few years there has been an incredible rise in the amount of game applications available for the latest generation of mobile platforms. An increasing amount of developers and companies are starting to invest more heavily in producing for this growing market. This report investigates some of the challenges faced when developing these games, with the focus on the genre turn based strategy games. The main areas that are explored are the time of a session with the device, the touchscreen control, the hardware and graphics, and finally the user interface. To accomplish this, three methods were used: creating a survey, testing successful game titles within the genre, and investigating various sources on the internet. The findings suggest that rounds should be possible to complete in considerably less time than a minute. Also, people seems to have no preference in the way a game is controlled as long as the controls fits the game well. In regards to graphics and hardware, it was shown that people do not see 3D graphics as a requirement and developers should not prioritize it over other aspects of the game. As for the user interface, amongst other conclusions, developers should aim to keep clickable items the same size across screen sizes instead of downscaling them for smaller devices 1
De senaste åren har antalet spelapplikationer för den senaste generationen mobila platformar ökat dramatiskt. Ett växande antal utvecklare och företag har börjat satsa mer och mer på att producera material till denna uppåtgående marknad. Den här rapporten utforskar några av de utmaningar som man ställs inför när man utvecklar spel till den mobila marknaden, med fokus på genren turbaserade strategispel. De områden som utreds i detalj är tiden för en spelsession, kontroll med pekskärmen, hårdvara och grafik, samt användargränssnitt. Tre metoder användes för att genomföra detta: skapa en enkät, testa inom genren framgångsrika spel, samt undersöka diverse källor på internet. Resultaten pekar mot att rundor bör vara möjliga att avsluta inom en minut. Det verkar också som att användare inte har några preferenser när det gäller hur ett spel ska kontrolleras så länge som kontrollerna passar spelet. Angående grafik och hårdvara så svarade enkättagare att 3D grafik inte är ett krav, utvecklare bör därför inte prioritera 3D grafik över andra delar av spelet. Utvecklare av användargränsnitt bör, bland annat, se till att clickbara ting på skärmen inte nerskalas på mindre skärmar utan håller en konsekvent storlek mellan olika skärmstorlekar.

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3

Kozuch, Kamil. "Contextual design for touch screen devices." Thesis, Södertörn University College, School of Communication, Media and it, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:sh:diva-3698.

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Designing touch screen devices includes many variables off how to address design issues in the best possible way. The design includes what type of touch interaction method is to be used, how the interface is to be designed and in which context it will be used. The problematic issue that has to be dealt with is how the designer must put together all these parameters into one final product. This paper presents the case of re-designing a touch screen bedside monitor, a device used in hospitals to observe the vital signs of patients. The design solution presented deals with the issues of how the device was designed to suit the users and environment of a hospital. A contextual inquiry showed the many constraints and standards that had to be met and how they shaped the design solution. Earlier work shows the different methods for touch interaction, interface design and feedback that can be applied for touch screen devices. The resulting design is discussed in relation to the different ways of creating touch screen interfaces, and an example of a work method is presented in the end of the paper on how to design for contextual touch screen devises.

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4

Shea, Patrick. "DESIGN AND MODELING OF RADIATION HARDENED LDMOSFET FOR SPACE CRAFT POWER SYSTEMS." Master's thesis, University of Central Florida, 2007. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/2822.

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NASA missions require innovative power electronics system and component solutions with long life capability, high radiation tolerance, low mass and volume, and high reliability in space environments. Presently vertical double-diffused MOSFETs (VDMOS) are the most widely used power switching device for space power systems. It is proposed that a new lateral double-diffused MOSFET (LDMOS) designed at UCF can offer improvements in total dose and single event radiation hardness, switching performance, development and manufacturing costs, and total mass of power electronics systems. Availability of a hardened fast-switching power MOSFET will allow space-borne power electronics to approach the current level of terrestrial technology, thereby facilitating the use of more modern digital electronic systems in space. It is believed that the use of a p+/p-epi starting material for the LDMOS will offer better hardness against single-event burnout (SEB) and single-event gate rupture (SEGR) when compared to vertical devices fabricated on an n+/n-epi material. By placing a source contact on the bottom-side of the p+ substrate, much of the hole current generated by a heavy ion strike will flow away from the dielectric gate, thereby reducing electrical stress on the gate and decreasing the likelihood of SEGR. Similarly, the device is hardened against SEB by the redirection of hole current away from the base of the device's parasitic bipolar transistor. Total dose hardness is achieved by the use of a standard complementary metal-oxide semiconductor (CMOS) process that has shown proven hardness against total dose radiation effects.
M.S.E.E.
School of Electrical Engineering and Computer Science
Engineering and Computer Science
Electrical Engineering MSEE

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5

Çetin, Aslı Seçkin Yavuz. "Applying product design methods to medical device design with a case study on home care devices/." [s.l.]: [s.n.], 2004. http://library.iyte.edu.tr/tezler/master/endustriurunleritasarimi/T000449.pdf.

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6

Huffman, Jamie. "Design of a microfluidic device for lymphatic biology." Thesis, Georgia Institute of Technology, 2011. http://hdl.handle.net/1853/42886.

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The lymphatic system has three primary roles: transporting lipids, transporting immune cells, and maintaining fluid balance. Each one of these roles are influenced by the presence of flow. Inflammation increases lymph flow, lipid uptake is enhanced by flow, cancer cell migration increases in the presence of flow, and lymphatic permeability and lymphatic contractility respond to changes in flow. Flow is very important to lymphatic function, and yet, there are no in vitro models that incorporate both luminal (flow along cell lumen) and transmural (flow through cell lumina) flow for lymphatics. To address this need, a microfluidic device has been developed that can incorporate both of these types of flow. This is achieved by driving flow through a channel which creates a pressure gradient that drives fluid through a porous membrane into an adjacent channel. Following several design iterations, the device can be easily fabricated, imaged, and cells can grow and survive in it. Permeability experiments have been performed in static and flow, 0.175 mL/min (0.5 dyne/cm²), cases. The effective permeability of dextran in the static and flow cases was calculated to be 0.0083 μm/s and 2.05 μm/s respectively. While the effective permeability of bodipy in the static and flow cases was calculated to be 0.0053 μm/s and 2.57 μm/s respectively. The static values are similar to values obtained in a transwell study by Dixon et al. As mentioned, lipid uptake is increased in the presence of flow and these numbers suggest the same. In addition to permeability studies, experiments were performed with cancer cells suspended in a collagen gel. Two image processing techniques were used to quantify cancer cell migration. The first technique was used to calculate the number of cells present at the beginning of the experiment and the number of cells that were ever present during the experiment in that particular z slice. The static case yielded a cell flux of 15 additional cells. While the two flow cases, within interstitial flow range, had a flux of 24 and 40 cells. This suggests that flow increases migration in cancer cells and is in agreement with the literature. The second technique was used to show that the cells in the static and flow cases are similarly motile, but the flow case is more directed in the z direction towards the membrane. The future work for this device is quite extensive, but a strong foundation centered around basic capabilities like inducing flow, seeding cells, and imaging has been formed.

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7

Pavesi, Alessandro. "Design and implementation of a Reinforcement Learning framework for iOS devices." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2022. http://amslaurea.unibo.it/25811/.

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Reinforcement Learning is an increasingly popular area of Artificial Intelligence. The applications of this learning paradigm are many, but its application in mobile computing is in its infancy. This study aims to provide an overview of current Reinforcement Learning applications on mobile devices, as well as to introduce a new framework for iOS devices: Swift-RL Lib. This new Swift package allows developers to easily support and integrate two of the most common RL algorithms, Q-Learning and Deep Q-Network, in a fully customizable environment. All processes are performed on the device, without any need for remote computation. The framework was tested in different settings and evaluated through several use cases. Through an in-depth performance analysis, we show that the platform provides effective and efficient support for Reinforcement Learning for mobile applications.

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8

Aftab, Ahmad. "Model-based design of haptic devices." Licentiate thesis, KTH, Mekatronik, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-98667.

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Efficient engineering design and development of high precision and reliable surgical simulators, like haptic devices for surgical training benefits from model-based and simulation driven design. The complexity of the design space, multi-domains, multicriteria requirements and multi-physics character of the behavior of such a product ask for a model based systematic approach for creating and validating compact and computationally efficient simulation models to be used for the design process.The research presented in this thesis describes a model-based design approach towards the design of haptic devices for simulation of surgical procedures, in case of hard tissues such as bone or teeth milling. The proposed approach is applied to a new haptic device based on TAU configuration.The main contributions of this thesis are: Development and verification of kinematic and dynamic models of the TAU haptic device. Multi-objective optimization (MOO) approach for optimum design of the TAU haptic device by optimizing kinematic performance indices, like workspace volume, kinematic isotropy and torque requirement of actuators. A methodology for creating an analytical and compact model of the quasi-static stiffness of haptic devices, which considers the stiffness of; actuation system;flexible links and passive joints.
QC 20120611

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9

Panikowska, Katarzyna E. "Service-oriented design of microfludic devices." Thesis, Cranfield University, 2011. http://dspace.lib.cranfield.ac.uk/handle/1826/5606.

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Microfluidics is a relatively new and, with an estimation of the market for these devices exceeding $3 billion in 2014, it is considered a profitable domain. Constant development of new technologies and growing demand for more versatile products cause increasing complexity in this area. To address this, the current trends for the domain include automation, standardisation and customisation. At the same time, the society is moving from product types offering to services. Due to the customisation trend this transition appears beneficial for microfluidics. Taking advantage of these opportunities, an investigation of microfluidic design has been undertaken to address the issues at their origins. The literature review showed a lack of a general design methodology applicable for all microfluidic devices, identified existing approaches as technology driven and the domain as unique in terms of design. Also, it highlighted a number of automation and standardisation attempts in the area. In addition, microfluidics shows limited customer and service-orientation. Meanwhile, an investigation of complexity and its implications in microfluidics narrowed the study to sub-section interactions, which allowed standardisation and automation without compromising customisation. In response to these gaps, an aim of the research is to develop a guideline for service- oriented design of microfluidic devices that can deal with sub-section interactions. This research reviews: existing methodologies for design in micro-scale, their applicability to the domain, microfluidic practitioners’ approach to design, state of service-thinking and services in the area and how sub-section interactions are dealt with for these devices. The developed guideline and design enablers present a proposal for a general process for the design of microfluidics. The solution attempts to tackle the issue of sub- section interactions and brings the domain one step towards an ‘experience economy’ by incorporating service-considerations into the design process. The usefulness of this contribution has been confirmed by a variety of methods and numerous sources including experts in the field.

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10

Hsieh, Pei-Shan. "IGBT design, modelling and novel devices." Thesis, University of Cambridge, 2015. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.708993.

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11

Winter, William Thomas. "Design and modeling of dielectrophoretic devices." Thesis, University of Cambridge, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.608451.

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12

Sutcliffe, Laura Francesca Rose. "Environmentally conscious design of medical devices." Thesis, University of Cambridge, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.610758.

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13

Nguyen, Loc Bao. "Logic design using programmable logic devices." PDXScholar, 1988. https://pdxscholar.library.pdx.edu/open_access_etds/4103.

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The Programmable Logic Devices, PLO, have caused a major impact in logic design of digital systems in this decade. For instance, a twenty pin PLO device can replace from three hundreds to six hundreds Transistor Transistor Logic gates, which people have designed with since the 60s. Therefore, by using PLD devices, designers can squeeze more features, reduce chip counts, reduce power consumption, and enhance the reliability of the digital systems. This thesis covers the most important aspects of logic design using PLD devices. They are Logic Minimization and State Assignment. In addition, the thesis also covers a seldomly used but very useful design style, Self-Synchronized Circuits. The thesis introduces a new method to minimize Two-Level Boolean Functions using Graph Coloring Algorithms and the result is very encouraging. The raw speed of the coloring algorithms is as fast as the Espresso, the industry standard minimizer from Berkeley, and the solution is equally good. The thesis also introduces a rule-based state assignment method which gives equal or better solutions than STASH (an Intel Automatic CAD tool) by as much as twenty percent. One of the problems with Self-Synchronized circuits is that it takes many extra components to implement the circuit. The thesis shows how it can be designed using PLD devices and also suggests the idea of a Clock Chip to reduce the chip count to make the design style more attractive.

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14

Brankin, S. "Magnetic and thermal modelling in alternator design." Thesis, Queen's University Belfast, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.317058.

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15

Clare, Jonathan Charles. "Computer aided design of power electronic systems." Thesis, University of Bristol, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.315209.

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16

Pallett, Edward. "Design and fabrication of a miniature silicon microphone." Thesis, De Montfort University, 1995. http://hdl.handle.net/2086/10719.

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Silicon micromachining techniques were developed and used to batch fabricate a new type of heavily doped p-type (or p") silicon etch stop structure on glass that could be suitable for implementation of a condenser microphone. This involved study, development and use of techniques such as mask design, lithography, oxidation, diffusion, thin film deposition, electrostatic bonding, many different etching techniques, freeze drying, packaging/interfacing and testing. The condenser microphone structure consisted of a thin conductive diaphragm suspended above a back plate electrode in order to form a capacitive device. A narrow gap between the two plates constituted the capacitor plate separation and the air occupying the gap was the dielectric material. Two versions of this condenser microphone structure were fabricated with over all dimensions of 2mm2 x 8-12 Jlm, air gap sizes of 0.5-1.5 Jlm and lum thick diaphragms. The first design utilised a square diaphragm with an area of lrnm" while the second incorporated a circular diaphragm with a diameter of lrnm. Fabrication of the back chambers was implemented with an innovative double thermal oxidation technique. Signals of up to ImVIPa were obtained in the audio range for one of the circular p+ silicon microphone structures, but the frequency response measured was not consistent with the desired frequency response for a condenser microphone. Thin film thicknesses, silicon etch rates and electrode metallisation conductivity were characterised using specially designed test structures and innovative electrical and opticalmeasurement techniques so that fabrication accuracy and reproducibility could be monitored. As a result of the investigations carried out to develop novel p" silicon microphone structures, this thesis also identifies important areas which warrant further research, and provides a foundation, in terms of theory and fabrication, for future development of more advanced and appropriate p + microstructures for application as condenser microphones.

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17

Bryson, Geraldine Mary. "Computer aided design of small salient pole alternators." Thesis, Queen's University Belfast, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.287295.

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18

Tamjis, Mohamad Rom Bin. "Computation of switched reluctance motor design and performance." Thesis, University of Newcastle Upon Tyne, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.386710.

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19

Benarous, Maamar. "The analysis and design of brushless D.C. motors." Thesis, University of Bath, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.267382.

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In modem computer systems electrical drives are used to rotate hard discs. These motors require special torque-speed characteristics. The speed of the hard disc must be constant in order for the unit to function correctly. One type of drive, which is used for hard discs is the brushless-DC-motor. This machine has permanent magnet excitation and a polyphase armature winding. It therefore takes the form of a synchronous machine, and in order to be brushless the armature winding is stationary and the excitation rotates. To run at adjustable speed a variable frequency supply is required. In the brushless D.C form the inverter output is phase locked to the rotor position, it is therefore electro-magnetically similar to the D.C machine where fixed brushes determine the frequency and phase of the current in the armature winding. In order to perform the phase lock action signals measuring the rotor position are needed. In one form of machine Hall effect probes detect the position of the rotor poles, in a second given that the rotor is in motion the induced back emf is used. Experimentally it is convenient to replace these magnet systems with a phototransistor and rotating shutter system and this was the approach used in this thesis. The objective of this research is to investigate different aspects of this motor. The generation, measurement, and placement of signals is described and illustrated, and the design and construction of an inverter supply circuit is described. Both 2D and 3D finite element analysis is used in order to find the machine parameters as well as cogging torque analysis, using the concept of permanent magnet magnetisation characteristics. It is shown that the cogging can be reduced for certain types of magnetisation. The finite element analysis is taken further by connecting the drive circuit needed to run the machine into the finite element mesh, the machine parameters are defined using this method. The close agreement between the simulation and practical results indicates that the complete modelling can be achieved using this method.The mathematical models of both Star, and Delta connected brushless DC machines are presented, and a complete model of the machine inverter system is built for both cases. The work is accomplished by the use of the Matlab analogue simulation toolbox, Simulink, and the simulation program calculates the electrical performances of both machines under steady state. The results obtained are compared to the experimental data, and a comparison between both machines is presented. A brushless DC motor using an insulated iron core material is presented, and analysed using 2D finite element analysis. The newly constructed machine is also tested and compared to the conventional version.

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20

Stead, Thomas. "An investigation into the application of design processes to novel self-use molecular diagnostic devices for sexually transmitted infections." Thesis, Brunel University, 2017. http://bura.brunel.ac.uk/handle/2438/15197.

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The purpose of this research was to investigate the application of design processes to the development of novel self-use molecular diagnostic devices for sexually transmitted infections. The argument proposed in this thesis is that the application of design methods at the earliest research stages into miniaturised, low cost, molecular diagnostic technologies will accelerate and improve the process of translating proof of concept diagnostic technologies into usable devices. Concept development requirements and potential issues and barriers to development were identified through interviews with expert stakeholders. These requirements were further refined through a survey of a multidisciplinary diagnostic medical device research group. An action research method was applied to develop a proof of concept prototype to the preclinical trial stage. Through these research studies, a design process model was formulated for use in a research environment. The application of design methods to the proof of concept prototype described in the thesis have resulted in a preclinical trial prototype that exhibits the necessary features for development into a self-use molecular diagnostic device. Issues and barriers were identified and discussed, design guidelines for further development beyond preclinical trial were defined and a generalised design process model for self-use molecular diagnostic devices for sexually transmitted infections was proposed. This research highlights the need for design methods to be applied at the earliest possible stages of the development of novel molecular diagnostic devices.

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21

Chin, Shaoan. "MOS-bipolar composite power switching devices." Diss., Virginia Polytechnic Institute and State University, 1985. http://hdl.handle.net/10919/54275.

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Two MOS-Bipolar composite power semiconductor switching devices are proposed and experimentally demonstrated. These devices feature high voltage and high current capabilities, fast switching speeds, simple gate drive requirements, savings in chip area, reverse bias second breakdown ruggedness and large safe operating areas. Application characteristics of the devices for high frequency power inverter circuits are discussed. Monolithic integration of the two composite devices are also proposed.
Ph. D.

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22

Fletcher, John Edward. "Design, analysis and control of a synchronous reluctance machine." Thesis, Heriot-Watt University, 1995. http://hdl.handle.net/10399/1202.

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23

Al-Amer, Itihad Abd Al-Hameed Abd. "A stable doubly-fed machine with novel rotor design." Thesis, Queen's University Belfast, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.335349.

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24

Aggarwal, Rakesh. "Computer aided design techniques for variable-reluctance stepping motors." Thesis, University of Cambridge, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.292938.

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25

Fair, Ruben Jeevanasan. "Analysis and design of electromagnetic moving coil vibration generators." Thesis, Imperial College London, 1991. http://hdl.handle.net/10044/1/7830.

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26

Lin, Julianna E. "Design and characterization of MEMS micromirror devices." Thesis, McGill University, 2001. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=32964.

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This thesis explores the design, implementation and characterization of MEMS micromirror devices for use in optical systems. Possible applications for these devices include areas such as adaptive optics, beam scanning, and optical switches. The devices were fabricated using a commercial MEMS foundry process, known as the Multi-User MEMS Processes (MUMPs) foundry service; the resulting prototypes were characterized using a phase-shifting Mirau interferometer, assembled specifically for this work. From these results, it was shown that the MUMPs process can be used to create satisfactory designs for rotational micromirrors with tilt angles in the range of 0--23 mrad and control voltages in the range of 0--30 V In addition, the behaviour of these mirrors were shown to fall within 5% of the predicted values calculated by the theoretical models for the devices.

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27

Pardo-Guzman, Dino Alejandro. "Design and processing of organic electroluminescent devices." Diss., The University of Arizona, 2000. http://hdl.handle.net/10150/284162.

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The present dissertation compiles three aspects of my Ph.D. work on OLED device design, fabrication and characterization. The first chapter is a review of the concepts and theories describing the mechanisms of organic electroluminescence. The second chapter makes use of these concepts to articulate some basic principles for the design of efficient and stable OLEDs. The third chapter describes the main characterization and sample preparation techniques used along this dissertation. Chapter IV describes the processing of efficient organic electroluminescent EL devices with ITO\TPD\AIQ₃\Mg:Ag structures. The screen printing technique of a hole transport polymeric blend was used in an unusual mode to render thin films in the order of 60-80 nm. EL devices were then fabricated on top of these sp films to provide ∼0.9% quantum efficiencies, comparable to spin coating with the same structures. Various polymer:TPD and solvent combinations were studied to find the paste with the best rheological properties. The same technique was also used to deposit a patterned MEH-PPV film. Chapter V describes my research work on the wetting of TPD on ITO substrates. The wetting was monitored by following its surface morphology evolution as a function of temperature. The effect of these surface changes was then correlated to the I-V-L characteristics of devices made with these TPD films. The surface roughness was measured with tapping AFM showed island formation at temperatures as low as 50-60°C. I Also investigated the effect of the purity of materials like AlQ3 on the device EL performance, as described in Chapter VI. In order to improve the purity of these environmentally degradable complexes a new in situ purification technique was developed with excellent enhancement of the EL cell properties. The in situ purification process was then used to purify/deposit organic dyes with improved film formation and EL characteristics.

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28

Tappin, Peter G. R. "Design and development of SIC power devices." Thesis, University of Newcastle Upon Tyne, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.514463.

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29

New, Edward G. "Design of multi-heterojunction organic photovoltaic devices." Thesis, University of Warwick, 2013. http://wrap.warwick.ac.uk/58079/.

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Organic photovoltaic (OPV) devices have shown great potential as an inexpensive source of renewable energy. There are many factors that affect the efficiency of an OPV device, and understanding them can help the design of new architectures to boost the efficiency towards a commercially viable level. Multijunction OPV devices have been realised as a key route to higher efficiencies. The work presented in this thesis focuses on the design of multi heterojunction OPV devices based upon small molecule organic semiconductors. A small molecule tandem OPV device consisting of two donor materials with complementary absorption spectra, boron subphthalocyanine chloride (SubPc) and aluminium phthalocyanine chloride (ClAlPc) combined with C60 as the acceptor is used as a test device architecture. The recombination layer between the sub-cells was investigated first, with the layer thickness and deposition conditions optimised. Modification of the photoactive layers by co-deposition of the donor and acceptor, and the use of a templating layer is proven to increase the device efficiency. α-NPD co-deposited with MoOx was used as a hole transport and optical spacer layer in single junction and tandem OPV devices. The electrical, optical and morphological properties of the α-NPD and the co-deposited layers are investigated. The hole transporting properties of α-NPD:MoOx are shown in a SubPc / C60 device with the optical spacing properties shown for a ClAlPc:C60 bulk heterojunction (BHJ) device. Implementation of the α-NPD:MoOx optical spacer layer is shown as a tool for current matching in a SubPc:C60 BHJ tandem OPV device. An optical simulation predicts the use of an optical spacer will improve the device performance as it positions the sub-cells in an optimum optical field position for current matching. Experimental results show good agreement with the optical simulation and an improvement in short circuit current (JSC) is shown with the α-NPD:MoOx optical spacer layer. The tandem OPV device is also shown with a larger active area which displays good operational stability characteristics. A multi-heterojunction cascade device was designed using α-sexithiophene (α-6T) as an interfacial layer with phthalocyanine / C60 OPV devices. The α-6T is shown to dissociate excitons in the phthalocyanine layer and contribute to the photocurrent of the device without affecting the phthalocyanine / C60 interface. The dual exciton dissociation in the cascade device leads to an increased JSC compared to the bilayer devices.

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30

Zhu, Weiming. "Photonic micromachined devices : design, fabrication and experiment." Phd thesis, Université Paris-Est, 2010. http://tel.archives-ouvertes.fr/tel-00596905.

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In this PhD project, three different approaches have been studied for tunable photonic devices based on MEMS technology. First, the optical double barrier structure has been numerically studied and experimentally demonstrated as the thermo-optical switch, switchable polarizer and optical tunneling junctions integrated as reconfigurable WDM system. Second, the slow light structure using metamaterial with coupled split ring unit cells is numerically analyzed. Finally, a tunable magnetic metamaterial is demonstrated using MEMS technology. The first major work is to use the optical tunneling effects to design MEMS based photonic devices. Three different tunable photonic devices has been demonstrated using thermo-optical tuning. a thermo-optic switch is realized using MEMS technology. The device is fabricated on silicon-on-isolator wafer using deep etching process. The transmission of the optical switch is controlled by the optical length of the central rib which is thermally controlled by the external pumping current. In experiment, it measures a switching speed of 1 us and an extinction ratio of 30 dB. A switchable polarizer is demonstrated using the double optical barrier structure which transmit the light with one polarization state and filter out the others. In experiment it measures a PER of lager than 23 dB when the pumping current is above 60mA. The switching time is shorter than 125 us which is limited by the polarization analyzer used in the experiment. A MEMS reconfigurable add-drop multiplexer is realized by applied the optical tunneling structure to the ribbed waveguide. The tunable add-drop multiplexer is based on Y-shape optical double barriers tunneling junction which are realized by MEMS technology

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31

Bao, Di. "Design and applications of optical transformation devices." Thesis, Queen Mary, University of London, 2012. http://qmro.qmul.ac.uk/xmlui/handle/123456789/3173.

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This thesis provides an insight into the designing, physical realization and characterization of optical transformation devices. It begins with an introduction to the discrete coordinate transformation with a design example of a carpet cloak. The realization and characterization of materials, namely a dielectric disk matrix and polyurethane/BaTiO3 foam composite, for constructing transformation optics devices are studied both numerically and experimentally. Two different kinds of low loss and broadband all-dielectric realisations of OT devices are designed and experimentally demonstrated. First, the cloaking structure made of a high-ǫ dielectric-loaded foam mixture is reported. A polyurethane foam, mixed with different ratios of barium titanate is used to produce the required range of permittivities, and the invisibility cloak is demonstrated to work for all incident angles, over a wide range of microwave frequencies. Then, based on a study on the properties of periodic dielectric particles, the cloak, realized with periodic dielectric cylinders, is proposed. The required dielectric map for the cloak is achieved by means of manipulating the dimensions, or spatial density, of the periodically distributed dielectric cylinders embedded in the host medium, whose permittivity is close to one. The scattering reduction effects are verified through both simulation and experimental results. The performances of the two different kinds of cloak are also compared quantitatively. Last, but not least, an extraordinary-transmission (ET) device made from commercially available ceramics and Teflon is designed, which exhibits broadband transmission through a sub-wavelength aperture. It is verified both numerically and experimentally that the device can provide transmission with a -3 dB bandwidth of more than 1 GHz, in a region which would otherwise be a stop band caused by the sub-wavelength aperture in an X-band waveguide.

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32

Rivera, Ortiz Phillip M. (Phillip Michael). "Phosphorylation based insulation devices design and implementation." Thesis, Massachusetts Institute of Technology, 2013. http://hdl.handle.net/1721.1/81622.

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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2013.
Cataloged from PDF version of thesis.
Includes bibliographical references (p. 85-87).
This thesis presents the analysis of a phosphorylation based insulation device implemented in Saccharomyces cerevisae and the minimization of the retroactivity to the input and retroactivity to the output of a single cycle phosphorylation device by means of optimal substrate and phosphatase concentration selection. Characterizing and improving the performance of insulation devices brings us a step closer to their successful implementation in biological circuits, and thus to modularity. To this end, an insulation device was designed and implemented in Saccharomyces cerevisae employing the principle of timescale separation. It was shown experimentally (data pending publication), that the dynamics of the insulation device output remained unchanged in the presence of promoter sites (load) providing retroactivity. In this thesis, the underlying mechanism by which the insulation device retains its dynamic performance in the presence of load is explained through singular perturbation and parameter sensitivity analysis. It was determined that the fast phosphotransfer reactions of the insulation device indeed allowed for retroactivity attenuation provided the substrate and phosphatase concentration are in sufficient amounts. Furthermore, the retroactivity to the input and retroactivity to the output of phosphorylation based insulation devices were parameterized with the substrate and phosphatase concentrations using a single cycle model. While previous works have focused on showing output retroactivity attenuation through high substrate and phosphatase concentration, it is shown that this has detrimental effects on the insulation device performance even in isolation. Employing singular perturbation and contraction theory tools, this work provides a framework to determine an optimal substrate and phosphatase concentration to reach a tradeoff between the retroactivity to the input and the retroactivity to the output.
by Phillip M. Rivera Ortiz.
S.M.

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33

Li, Weifeng. "Carbon Nanotube Materials Characterization and Devices Design." University of Cincinnati / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1298043357.

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34

Adil, Farhan. "Offset reduction using floating-gate devices." Thesis, Georgia Institute of Technology, 2003. http://hdl.handle.net/1853/14945.

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35

Ward, Gillian Anne. "Design of a multi-kilowatt, high frequency, DC-DC converter." Thesis, University of Birmingham, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.274596.

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36

Monkhouse, Peter. "Design and analysis of a high performance brushless DC drive." Thesis, University of Sheffield, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.389485.

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37

Garst, Sebastian. "Design and production of polymer based miniaturised bio-analytical devices." Australasian Digital Thesis Program, 2007. http://adt.lib.swin.edu.au/public/adt-VSWT20071003.082618/index.html.

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Thesis (MEng) - Swinburne University of Technology, Industrial Research Institute Swinburne - 2007.
A thesis submitted for fulfillment of the requirement for the degree of Master of Engineering, Industrial Research Institute, Swinburne University of Technology - 2007. Typescript. Includes bibliographical references (p. 148-155).

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38

Al-Akayshee, Qasim Hamood. "Design, construction and operation of an A.C. side excited machine." Thesis, University of Bath, 1996. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.337822.

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39

Murphy, Robert S. "The design of safety-critical medical infusion devices." Thesis, University of South Wales, 2007. https://pure.southwales.ac.uk/en/studentthesis/the-design-of-safetycritical-medical-infusion-devices(1557c702-3087-43f9-a399-99a9ba65ae9b).html.

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Intravenous infusion devices - commonly known as infusion pumps - provide clinicians with mechanisms to automate the accurate dosing of potent fluid therapies to critically ill patients. In critical care applications, fluid dosing must be both accurate and safe since unwanted flow disturbance can cause physiological harm to the patient. This study consists of three discrete projects based on these vital themes of safe device design and accurate fluid delivery. The first project, commissioned by Medical Magnetics Ltd during the period 1998 onwards, proposed that the fail-safe design philosophy universally used in the design of infusion pumps, and implemented in embedded software, is lengthy and provides the manufacturer with difficulties in demonstrating the exhaustive fail-safe validation needed for an instrument to be released speedily for sale. An alternative and innovative strategy employing the design of hardware modules and using re-configurable VLSI, is proposed and shown to offer a significant reduction of the design and validation phase of development with consequent financial benefit to the manufacturer. The second project conducted as part of the Manukau Institute Research Programme for 2003 examined the manner in which dosing accuracy is assessed for infusion pumps. The International Standard used by clinicians to select apparatus suitable for treatment of 'critically-ill' patients is shown to be flawed and potentially misleading - a finding of international significance. An innovative mathematical simulation model is described that enables prediction of flow accuracy for various expected operating scenarios previously impossible to investigate using current laboratory measurement techniques. Use of this simulation model indicates that various mechanical design factors influencing system compliance and hence dosing accuracy have been previously ignored by designers and suggests that contemporary infusion pump designs are far from optimum. These findings offer an explanation for instances of dosing error previously reported in the clinical literature and are of international value. The third project of the study utilises the findings of, and is subsequent to, the second project. An innovative design is proposed for an infusion therapy device in which dosing accuracy may be maintained under operating conditions such as height change and patient venous pressure variation that cause unwanted errors in conventional equipment designs. This design is the subject of patent application, commercial exploitation and further development.

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40

Beignon, Anaëlle. "Design for obsolete devices. : Exploring the marginalization of users of obsolete devices regarding the Swedish public services’ digitalization." Thesis, Malmö universitet, Institutionen för konst, kultur och kommunikation (K3), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-43842.

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This thesis project addresses the obsolescence of technology through the lens of accessibility to public services. It explores the processes by which electronic devices age in regards to a technological normativity that marginalizes owners of obsolete devices. My research focuses on two main questions: How might we enable owners of non-smart phones to have access to public services that have been digitalized? How might we design public services’ infrastructure in a way that challenges the obsoletion processes of technological devices? The research is based upon a critical analysis of the term ‘obsolescence’, low-tech approaches and studies that examine the accessibility of technology. This work is based on the study of the digitalization of public services in Sweden, with specific attention to public transportation and to the electronic identification technology which enables access to various essential public services. I present the exploration of these services through the lens of obsolescence and encounter with users of obsolete devices. This leads to the design of two prototypes that propose ways of integrating obsolete devices’ users in the existing digitalized Swedish infrastructures, followed by their analysis. The designs seek to take a critical stand on technological progress as it is understood in the technology industry and propose ways of reimagining the digitalization of public services while taking into account the obsoletion processes they foster. Overall, I argue for design for obsolete devices as a way of caring for groups that are put aside during technological innovation processes. I propose ways of ‘circuit bending’ public services’ infrastructures in a way that is more hospitable to obsolete devices.

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41

Rezaei-Lori, Ahmad Ali. "Design and simulation of brushless DC drive systems for industrial applications." Thesis, Cardiff University, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.336117.

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42

Tam, C. H. "Design and development of axial-field air-cored brushless DC motors." Thesis, University of Warwick, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.370229.

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43

Hu, Gongfan. "Computer aided analysis and design of a single phase induction actuator." Thesis, University of Dundee, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.334764.

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44

Zhou, Dawei. "Finite element analysis and design optimisation of shaded pole induction motors." Thesis, Abertay University, 2001. https://rke.abertay.ac.uk/en/studentTheses/ba129f34-0df4-4154-a966-5a369640723d.

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In the area of performance analysis of the Shaded Pole Induction Motors (SPIMs),much research has been done with different equivalent circuit models, but the results are generally not satisfactory. The emergence of Finite Element (FE) methods provides an opportunity to take a fresh look at the design of SPIMs and this forms the backbone of my research. In the research, a more accurate two-dimensional time-stepping eddy-current FE model was developed. The multi-slice technique, justified as the more efficient way to consider the effect of a skewed rotor, has been adopted in the model. For the first time,the end-ring resistance was investigated under the condition that the end-ring current distributes itself non-sinusoidally along the circumferential direction in the end-ring area. An instantaneous non-uniform end-ring resistance model was therefore presented and coupled with the two-dimensional multi-slice FE model. Thus, compared with using the normal two-dimensional FE model, the three-dimensional nature of electric machines, e.g. the skew and end-ring, could be considered more properly by using the proposed FE Model. Meanwhile, the harmonics, the skin effect and the saturation of the permeable parts can all be taken into account with the new model. On the other hand, in order to reduce the computing time required, by the time-stepping technique, a variable step size method was adopted and a more reliable method of estimating the truncation error of time-stepping has been developed. Additionally, by coupling the external circuits equations directly to the field equations, the time cost was further reduced and the performance of a SPIM including current and torque might be obtained immediately after the systems equations were solved. With the developed two-dimensional FE model, the effects of variation of design parameters, including air gap profile, pole bridge, the skew, rotor slot number and closed-slot rotor, have been investigated. By introducing a new harmonic analysis method based directly on the time-stepping finite element method, the effect of different designs on the spatial harmonic in the air gap field and the time harmonic in the rotorbar current can be learned. The optimisation technique was applied to the design of SPIMs in order to obtain a proper combination of the design variables. A more efficient global-local hybrid search algorithm that combines the Genetic Algorithm with the direct search method was proposed in this study. To meet the demand of either speed or accuracy, a multi-slice fixed-mesh model of SPIMs was built up and used to calculate of the motor performance, the objective function of the optimisation. Because the optimisation program was based on FE analysis directly, an automatic re-mesh scheme depending on the optimisation variables was required and therefore developed in this research as well. A great performance improvement was achieved when applying the proposed optimisation method to maximising the starting torque. Finally, In order to validate the result of the two-dimensional, multi-slice FE model proposed, a PC-based experimental rig has been set up. With this test rig, two SPIMs have been tested in both the steady state and the transient state and the measuring results proved the accuracy of the analysis model developed in the study.

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45

Alyammahi, Saleimah. "Design and Simulation of Multifunctional Optical Devices Using Metasurfaces." University of Dayton / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1508340337384298.

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46

Elani, U. "The design, fabrication and assessment of interdigitated back contact silicon solar cells." Thesis, Cardiff University, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.354744.

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47

Akmese, Recep. "Design, operation and dynamic performance of a brushless DC tubular drive system." Thesis, University of Bath, 1989. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.328876.

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48

Pokorný, Martin. "Design defibrilátoru." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2010. http://www.nusl.cz/ntk/nusl-228921.

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This master’s thesis deals with design of defibrillator. It is a medical device for restoration of proper heart rhythm. The proposal respects the current production, but should draw their own concepts. The actual solution consisting in a combination of manual and fully automatic defibrillator. Applicability should include a wide range of expertise. The proposal is completely prepared in compliance with all aspects of construction of defibrillator.

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49

SCHOENEMAN, DONALD WARREN. "COMPUTER-AIDED DESIGN OF THERMIONIC INTEGRATED CIRCUIT ACTIVE DEVICES." Diss., The University of Arizona, 1985. http://hdl.handle.net/10150/188077.

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Two computer-aided design methods are described in this dissertation for the design of Thermionic Integrated Circuits (TIC). Such circuits combine vacuum tube techniques with modern integrated circuit techniques to produce microminiature vacuum tube circuits, with possibly hundreds of vacuum triodes on a single substrate. The first method described in the line charge approximation technique in which the TIC devices are modelled as collections of line charges. A TIC is produced by evaporating metal electrodes on one or two sapphire substrates. The entire structure is heated to about 850°C so that electrons are emitted from the cathode electrodes to travel to the plate electrodes as in a conventional vacuum triode. The line charge approximation method is easy to implement and provides a simple means of satisfying the sapphire dielectric boundary conditions of the TIC basic problems, which are electrostatics problems since space charge effects are neglected. The method requires only a single matrix inversion and is a finite element Green's function approach. The method uses no iteration as in previous TIC analysis methods. Later as the development of TIC devices proceeded further it was found that conducting shields had to be placed over the unused sapphire surface so that the basic problem became a metal box problem. For this case a second method was developed called the step and ramp function method in which each electrode is modelled by a step function, which is the electric field solution for a potential step on a zero potential boundary. A superposition of these step functions models the TIC electrodes. The method provides direct calculation of the electric fields from equations and requires no iteration or matrix inversion. The potential variation between electrodes is modelled by linear potential functions called ramps. A superposition of steps and ramps completely specifies a TIC structure. The method does not solve for the case of electrodes which are elevated above substrates. For this case a modified line charge method was developed but not implemented.

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50

Almajid, Abdulhakim A. "Design of high performance piezo composites actuators /." Thesis, Connect to this title online; UW restricted, 2002. http://hdl.handle.net/1773/7130.

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Дисертації з теми "Design of devices"

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