Дисертації: "Integration of active systems"

1

Rengaraj, Chandrasekaran. "Integration of active chassis control systems for improved vehicle handling performance." Thesis, University of Sunderland, 2012. http://sure.sunderland.ac.uk/4017/.

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This thesis investigates the principle of integration of vehicle dynamics control systems by proposing a novel control architecture to integrate the brake-based electronic stability control (ESC), active front steering (AFS), normal suspension force control (NFC) and variable torque distribution (VTD). A nonlinear 14 degree of freedom passive vehicle dynamics model was developed in Matlab/Simulink and validated against commercially available vehicle dynamics software CarSim. Dynamics of the four active vehicle control systems were developed. Fuzzy logic and PID control strategies were employed considering their robustness and effectiveness in controlling nonlinear systems. Effectiveness of active systems in extending the vehicle operating range against the passive ones was investigated. From the research, it was observed that AFS is effective in improving the stability at lower lateral acceleration (latac) region with less interference to the longitudinal vehicle dynamics. But its ability diminishes at higher latac regions due to tyre lateral force saturation. Both ESC and VTD are found to be effective in stabilising the vehicle over the entire operating region. But the intrusive nature of ESC promotes VTD as a preferred stability control mechanism at the medium latac range. But ESC stands out in improving stability at limits where safety is of paramount importance. NFC is observed to improve the ability to generate the tyre forces across the entire operating range. Based on this analysis, a novel rule based integrated chassis control (ICC) strategy is proposed. It uses a latac based stability criterion to assign the authority to control the stability and ensures the smooth transition of the control authority amongst the three systems, AFS, VTD and ESC respectively. The ICC also optimises the utilisation of NFC to improve the vehicle handling performance further, across the entire operating regions. The results of the simulation are found to prove that the integrated control strategy improves vehicle stability across the entire vehicle operating region.

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2

Strahler, Jeremy A. "Integration of an active optical system for Flexlab." Ohio : Ohio University, 2000. http://www.ohiolink.edu/etd/view.cgi?ohiou1173204753.

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3

Björkman, Mårten. "Real-Time Motion and Stereo Cues for Active Visual Observers." Doctoral thesis, KTH, Numerical Analysis and Computer Science, NADA, 2002. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3382.

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4

Zetterqvist, Robert. "Fault localization in IP-based communication infrastructure : Improving network information systems through active equipment integration." Thesis, KTH, Kommunikationsnät, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-169517.

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5

El, Hindi Khalil. "Integrating truth maintenance systems with active database systems for next generation cooperative systems." Thesis, University of Exeter, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.385771.

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6

Sarmiento, Leon Mayra Susana. "Testing platform implementation and system integration for an active/passive imager system including readout circuit design." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file 5.32 Mb., 170 p, 2006. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&res_dat=xri:pqdiss&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft_dat=xri:pqdiss:3220740.

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7

Tonnis, Kevin. "Integration of Highly Active Pt-Sn Nanoparticles into Practical Hydrogen and Direct Ethanol Fuel Cell Systems." University of Cincinnati / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1535464302229881.

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8

Al-Haddad, Tristan Farris. "PerFORMance: Integrating Structural Feedback into Design Processes for Complex Surface-Active Form." Thesis, Available online, Georgia Institute of Technology, 2006, 2006. http://etd.gatech.edu/theses/available/etd-07102006-111810/.

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9

Chiang, Mao-Hsiung, Yung-Ching Sung, and Han-Hsiang Liu. "A Study on Integration of Energy Harvesting System and Semi-Active Control for a Hydraulic Suspension System." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-199913.

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Suspension systems are used to diminish the vibration of vehicles. The hydraulic dampers in conventional suspension systems are mainly designed with the orifices of the piston; however, the vibration energy will be transferred into waste heat. In recent years, conventional vehicles with internal combustion engines and hybrid vehicles are used commonly. However, with the gradual depletion of fossil fuels, electric vehicles are developing. For this reason, the research focuses on recycling energy from the suspension of vehicles to improve the vehicle’s endurance. The purpose of this study is to develop a semi-active suspension control system with an energy harvesting system. Instead of the fixed orifices in conventional vehicles, an adjusting damping force method with variable resistance circuits system is studied for the semi-active suspension control system. Thus, we are able to develop semi-active control to improve the riding comfort. The energy harvesting system contains a hydraulic gear motor and a DC generator. When vehicles vibrate, the hydraulic damper serves as a hydraulic pump to compress the oil and drive the hydraulic motor. At the same time, the hydraulic motor drives the generator to generate electricity which will be stored in a battery. In this study, the test rig is the quarter-car system. We first design the novel hydraulic suspension system combining with the energy harvesting system. The simulation of dynamic mathematical model will be performed and analyzed by MATLAB/Simulink. Besides that, the semiactive control by the fuzzy sliding mode controller will be realized in the hydraulic suspension system with energy harvesting system. Finally, a test rig is set up for practical experimental implementation and verification.

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10

Towe, James Barry. "Integration and iteration of documentation and interactive systems development via the User Action Notation (UAN)." Master's thesis, This resource online, 1993. http://scholar.lib.vt.edu/theses/available/etd-12232009-020228/.

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11

Ghose, Agneta. "Life Cycle Assessment of an Active House : Sustainability concepts by integrating energy, environment and well-being." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for bygg, anlegg og transport, 2012. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-19316.

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An emerging interest in constructing ultra low energy buildings, with low impact materials and maximizing the potential of using renewable energy reflects the potential in building industry to significantly contribute towards reducing environmental impacts. Life cycle assessments of the different green building prototypes provide a means to estimate the impacts of such buildings as well as provide suggestive improvements. The Active house in Stjørdal, Norway is one such prototype of a green building. This is a single family residence which is built with a concept of solar architecture in ultra low-energy buildings. It is challenging to harness solar energy at high latitudes. The Active house uses the fundamental construction details for a Passive house as mentioned in Norwegian regulatory standard, with specific changes in increasing the glazed surface to promote passive solar heat gain as well as increase daylighting , but also making it vulnerable to heat loss. The house is based on timber framework. Apart from electricity the house uses solar collectors which are connected to the hot water storage and hydronic floor heating. Space heating is also compensated by use of wood stoves. In the LCA results suggest that, based on the construction the Active house requires ten percent more energy than an equivalent Passive house which uses only electricity and wood. However, due to the effectivity of the solar collectors, it compensates for the need of the extra energy and in a lifetime of 60 years, it performs 15 % better , contributing to lesser environmental impacts than an equivalent Passive house. It is understood that extra embodied energy does not affect the environmental performance of a building if it results in better environmental performance (1). However, it is important to create demonstrable value of the building for the end user. Lifecycle assessment results from simulated operational use carries considerable error with respect to how the building actually performs. The results in this study have also been estimated with an approximate error factor derived from previous studies (2). There is a necessity to make every stakeholder of the building participative in the functioning of the building, inclusive of the end user, and maintaining the well-being. The case has also been scored in the basic categories of a sustainibility certification, with the results available from the lifecycle assessment and energy simulation.

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12

Malekzadeh, Fatemeh. "Integration of Phase Change Materials in Commercial Buildings for Thermal Regulation and Energy Efficiency." Thesis, The University of Arizona, 2015. http://hdl.handle.net/10150/603534.

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One of prospective procedures of absorbing thermal energy and releasing it during the required time is the application of phase change materials known as PCMs in building envelopes. High thermal energy storage (TES) materials has been a technology that effects the energy efficiency of a building by contributing in using onsite resources and reducing cooling or heating loads. Currently, many TES systems are emerging and contributing in building assemblies, however using an appropriate type of TES in a specific building and climate requires an in-depth knowledge of their properties. This research aims to provide a thorough review of a broad range of thermal energy storage technologies including their potential application in buildings. Subsequently, a comparative study and simulation between a basecase and an optimized model by PCM is thoroughly considered to understand the effect of high thermal storage building's shell on energy efficiency and indoor thermal comfort. Specifically this study proposes that the incorporation of PCM into glazing system as a high thermal capacity system will improve windows thermal performance and thermal capacity to varying climatic conditions. The generated results by eQUEST energy modeling software demonstrates approximately 25% reduction in cooling loads during the summer and 10% reduction in heating loads during the winter for optimized office building by PCM in hot arid climate of Arizona. Besides, using PCM in glazing system will reduce heat gain through the windows by conduction phenomenon. The hourly results indicates the effect of PCM as a thermal energy storage system in building envelopes for building's energy efficiency and thermal regulation. However, several problems need to be tackled before LHTES can reliably and practically be applied. We conclude with some suggestions for future work.

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13

Sahin, Murat. "Design And Simulation Of An Abs For An Integrated Active Safety System For Road Vehicles." Master's thesis, METU, 2007. http://etd.lib.metu.edu.tr/upload/2/12608801/index.pdf.

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Active safety systems for road vehicles have been improved considerably in recent years along with technological advances and the increasing demand for road safety. In the development route of active safety systems which started with introduction of digital controlled ABS in the late seventies, vehicle stability control systems have been developed which today, with an integration approach, incorporate ABS and other previously developed active safety technologies. ABS, as a main part of this new structure, still maintains its importance. In this thesis, a design methodology of an antilock braking system controller for four wheeled road vehicles is presented with a detailed simulation work. In the study, it is intended to follow a flexible approach for integration with unified control structure of an integrated active safety system. The objective of the ABS controller, as in the previous designs in literature, is basically to provide retention of vehicle directional control capability and if possible shorter braking distances by controlling the wheel slip during braking. iv A hierarchical structure was adopted for the ABS controller design. A high-level controller, through vehicle longitudinal acceleration based estimation, determines reference slip values and a low-level controller attempts to track these reference slip signals by modulating braking torques. Two control alternatives were offered for the design of the low-level controller: Fuzzy Logic Control and PID Control. Performance of the ABS controller was analyzed through extensive simulations conducted in MATLAB/Simulink for different road conditions and steering maneuvers. For simulations, an 8 DOF vehicle model was constructed with nonlinear tires.

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14

Hernandez, Jorge Eliezer. "Third harmonic management and flexible charging for the integration of electric vehicles into the grid." Diss., Georgia Institute of Technology, 2015. http://hdl.handle.net/1853/53495.

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Electric vehicle (EV) development has gone into an accelerated pace in recent years to address pressing concerns on energy security, the environment, and the sustainability of transportation. The future market success of EVs is still uncertain, but the current shift in the automotive industry is indicating a possible bright future for EVs. Because of its unique load characteristics, an extensive deployment of EVs will not only bring challenges to power systems, but will enable new opportunities as well. The objective of this work is to address the increased third harmonic currents expected with the introduction of EVs and to explore the potential of leveraging flexible EV charging to increase wind power production. Since EV chargers rely on a nonlinear power conversion process to obtain a controllable DC source from the utility AC supply, it is expected that these devices will aggravate third harmonic current issues. In fact, utility harmonic field data show that, even without EVs, distribution feeders are already experimenting elevated levels of third harmonic currents. To address present and future utility harmonic filtering needs, a practical third harmonic hybrid active filter for medium voltage (MV) applications is proposed. Its design is based on strict utility requirements of cost, reliability, and ease of system implementation. The operation and performance of the proposed filter is verified through simulations and two experimental setups, one tested at 7.2 kV. Furthermore, a system impact study of the proposed filter is performed using actual data for a typical residential/small commercial distribution feeder. Because vehicles remain stationary most of the time, EVs have the potential of being flexibly charged, providing a spectrum of opportunities for system operators. The recent increase in wind power penetration in the U.S. is raising concerns on how to accommodate this stochastic renewable energy resource in day-ahead scheduling operations. In this work, a detailed integrated day-ahead scheduling framework is developed to explore the impact of leveraging flexible EV charging to balance out the variability and uncertainty of wind power generation. It is determined that the full benefits of balancing wind power generation with flexible EV charging may not be achieved in congested power systems. A potential solution based on deploying power routers (PRs) to augment the flexibility of the transmission system is proposed. Simulation results are presented for a test system based on the IEEE 39-bus system.

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15

Pentarchou, Konstantina. "Web 2.0 tools integration in Online Public AccessCatalogue (OPAC) : users desires and motivation." Thesis, Linnéuniversitetet, Institutionen för informatik (IK), 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-36326.

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This research aimed to investigate the desires of the users of the Greek public Library on Gender and Equality (LGE) about a future Online Public Access Catalogue (OPAC) containing Web2.0 functionalities. The concepts of participation, information pluralism and community building in relation with Web 2.0 tools in libraries’ catalogues were introduced under the theoretical approach provided by Social Critical Theory of Jürgen Habermas. Aqualitative research based on semi-structured interviews with users of the LGE wasconducted and the collected data that were analysed with the thematic analysis method,revealed positive users’ impressions regarding the introduction of Web 2.0 tools in theLGE’s OPAC. The research also disclosed users’ desires and suggestions regarding specific Web 2.0 features and their common motivation to participate and contribute to be the opportunity of communicating with like-minded people.

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16

Mattlet, Benoit. "Potential benefits of load flexibility: A focus on the future Belgian distribution system." Doctoral thesis, Universite Libre de Bruxelles, 2018. https://dipot.ulb.ac.be/dspace/bitstream/2013/271127/5/contratBM.pdf.

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Since the last United Nations Climate Change Conference in 2015 in Paris (the COP 21), world leaders acknowledged climate change. There is no need any more to justify the switch from fossil fuel-based to renewable energy sources. Nevertheless, this transition is far from being straightforward. Besides technologies that are not yet mature -- or at least not always financially viable in today's economy -- the power grid is currently not ready for a rapid and massive integration of renewable energy sources. A main challenge for the power grid is the inadequacy between electric production and consumption that will rise along with the integration of such sources. Indeed, due to their dependence on weather, renewable energy sources are intermittent and difficult to forecast with today's tools. As a commodity, electricity is a quite distinct good for which there must be perfect adequacy of production and consumption at all time and characterized by a very inelastic demand. High shares of renewable energy sources lead to high price volatility and a higher risk to jeopardize the security of supply. Additionally, the switch to renewable energy sources will lead to an electrification of loads and transportation, and thus the emergence of new higher-consumption loads such as electric vehicles and heat pumps. These new and higher-consumption loads, combined with the population growth, will cause over-rated power load increases with less predictable load patterns in the future.This work focuses on issues specific to the distribution power grid in the context of the current energy transition. Traditional low-voltage grids are perhaps the most passive circuits in power grids. Indeed, they are designed primarily using a fit and forget approach where power flows go from the distribution transformer to the consumers and no element has to be operated or regularly managed. In fact, low-voltage networks completely lack observability due to very low monitoring. The distribution grid will especially undergo drastic changes from this energy transition. Distributed sources and new high-consumption -- and uncoordinated -- loads result in new power flow patterns, as well as exacerbated evening peaks for which it is not designed. The consequences are power overloads and voltage imbalances that deteriorate grid components, such as a main asset like the medium-to-low voltage transformer. Additionally, the distribution grid is characterized by end-users that pay a price for electricity that does not reflect the grid situation -- that is, mostly constant over a year -- and allow little to no actions on their consumption.These issues have motivated authorities to propose a global approach to ensure security of electricity supply at short and medium-term. The latter requires, among others, the development of demand response programs that encourage users to take advantage of load flexibility. First, we propose adequate electricity pricing structures that will allow users to unlock the potential of such demand response programs; namely, dynamic pricings combined with a prosumer structure. Second, we propose a fast and robust two-level optimization, formulated as a mixed-integer linear program, that coordinates flexible loads. We focus on two types of loads; electric vehicles and heat pumps, in an environment with solar PV panels. The lower level aims at minimizing individual electricity bills while, at the second level, we optimize the power load curve, either to maximize self-consumption, or to smoothen the total power load of the transformer. We propose a parametric study on the trade-off between only minimizing the individual bills versus only optimizing power load curves, which have proven to be antagonist objectives. Additionally, we assess the impact of the rising share of flexible loads and renewable energy sources for scenarios from today until 2050. A macro-analysis of the results allows us to assess the benefits of load flexibility for every actor of the distribution grid, and depending on the choice of a pricing structure. Our optimization has proved to prevent evening peaks, which increases the lifetime of the distribution transformer by up to 200%, while individual earnings up to 25% can be made using adequate pricings. Consequently, the optimization significantly increases the power demand elasticity and increases the overall welfare by 10%, allowing the high shares of renewable energy sources that are foreseen.
Doctorat en Sciences de l'ingénieur et technologie
info:eu-repo/semantics/nonPublished

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17

Ellison, Thomas A. "Toward Transforming Health Systems: A Practice Study of Organizing and Practical Inquiry in Academic Medicine." Antioch University / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=antioch1445818686.

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18

Papadakis, Ktistakis Iosif. "An Autonomous Intelligent Robotic Wheelchair to Assist People in Need: Standing-up, Turning-around and Sitting-down." Wright State University / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=wright1546469803313219.

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19

Chandler, Dawn, John Dachos, Barbara DeBary-Kesner, Jimmy Howard, and Sherry Springs. "Human Systems Integration." Monterey, California. Naval Postgraduate School, 2011. http://hdl.handle.net/10945/7090.

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Purpose: Provide overview of Human Systems Integration (HSI) Inputs to the Capabilities Development Document (CDD), Provide an overview of the Localized Electromagnetic Directed Disrupter Device (LED3) Focus on the 7 HSI domains

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20

Ezz, Inas E. "Management support systems integration." Thesis, Brunel University, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.365077.

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21

Akeel, Fatmah Y. "Secure data integration systems." Thesis, University of Southampton, 2017. https://eprints.soton.ac.uk/415716/.

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As the web moves increasingly towards publishing data, a significant challenge arises when integrating data from diverse sources that have heterogeneous security and privacy policies and requirements. Data Integration Systems (DIS) are concerned with integrating data from multiple data sources to resolve users' queries. DIS are prone to data leakage threats, e.g. unauthorised disclosure or secondary use of the data, that compromise the data's confidentiality and privacy. We claim that these threats are caused by the failure to implement or correctly employ confidentiality and privacy techniques, and by the failure to consider the trust levels of system entities, from the very start of system development. Data leakage also results from a failure to capture or implement the security policies imposed by the data providers on the collection, processing, and disclosure of personal and sensitive data. This research proposes a novel framework, called SecureDIS, to mitigate data leakage threats in DIS. Unlike existing approaches that secure such systems, SecureDIS helps software engineers to lessen data leakage threats during the early phases of DIS development. It comprises six components that represent a conceptualised DIS architecture: data and data sources, security policies, integration approach, integration location, data consumers, and System Security Management (SSM). Each component contains a set of informal guidelines written in natural language to be used by software engineers who build and design a DIS that handles sensitive and personal data. SecureDIS has undergone two rounds of review by experts to conrm its validity, resulting in the guidelines being evaluated and extended. Two approaches were adopted to ensure that SecureDIS is suitable for software engineers. The first was to formalise the guidelines by modelling a DIS with the SecureDIS security policies using Event-B formal methods. This verified the correctness and consistency of the model. The second approach assessed SecureDIS's applicability to a real data integration project by using a case study. The case study addressed the experts' concerns regarding the ability to apply the proposed guidelines in practice.

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22

Zumdieck, Alexander. "Dynamics of Active Filament Systems." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2006. http://nbn-resolving.de/urn:nbn:de:swb:14-1139849910030-68242.

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Aktive Filament-Systeme, wie zum Beispiel das Zellskelett, sind Beispiele einer interessanten Klasse neuartiger Materialien, die eine wichtige Rolle in der belebten Natur spielen. Viele wichtige Prozesse in lebenden Zellen wie zum Beispiel die Zellbewegung oder Zellteilung basieren auf dem Zellskelett. Das Zellskelett besteht aus Protein-Filamenten, molekularen Motoren und einer großen Zahl weiterer Proteine, die an die Filamente binden und diese zu einem Netz verbinden können. Die Filamente selber sind semifexible Polymere, typischerweise einige Mikrometer lang und bestehen aus einigen hundert bis tausend Untereinheiten, typischerweise Mono- oder Dimeren. Die Filamente sind strukturell polar, d.h. sie haben eine definierte Richtung, ähnlich einer Ratsche. Diese Polarität begründet unterschiedliche Polymerisierungs- und Depolymerisierungs-Eigenschaften der beiden Filamentenden und legt außerdem die Bewegungsrichtung molekularer Motoren fest. Die Polymerisation von Filamenten sowie Krafterzeugung und Bewegung molekularer Motoren sind aktive Prozesse, die kontinuierlich chemische Energie benötigen. Das Zellskelett ist somit ein aktives Gel, das sich fern vom thermodynamischen Gleichgewicht befindet. In dieser Arbeit präsentieren wir Beschreibungen solcher aktiven Filament-Systeme und wenden sie auf Strukturen an, die eine ähnliche Geometrie wie zellulare Strukturen haben. Beispiele solcher zellularer Strukturen sind Spannungsfasern, kontraktile Ringe oder mitotische Spindeln. Spannungsfasern sind für die Zellbewegung essentiell; sie können kontrahieren und so die Zelle vorwärts bewegen. Die mitotische Spindel trennt Kopien der Erbsubstanz DNS vor der eigentlichen Zellteilung. Der kontraktile Ring schließlich trennt die Zelle am Ende der Zellteilung. In unserer Theorie konzentrieren wir uns auf den Einfluß der Polymerisierung und Depolymerisierung von Filamenten auf die Dynamik dieser Strukturen. Wir zeigen, dass der kontinuierliche Umschlag (d.h. fortwährende Polymerisierung und Depolymerisierung) von Filamenten unabdingbar ist für die kontraktion eines Rings mit konstanter Geschwindigkeit, so wie in Experimenten mit Hefezellen beobachtet. Mit Hilfe einer mikroskopisch motivierten Beschreibung zeigen wir, wie "filament treadmilling", also Filament Polymerisierung an einem Ende mit der gleichen Rate wie Depolymerisierung am anderen Ende, zur Spannung in Filament Bündeln und Ringen beitragen kann. Ein zentrales Ergebnis ist, dass die Depolymerisierung von Filamenten in Anwesenheit von filamentverbindenden Proteinen das Zusammenziehen dieser Bündel sogar in Abwesenheit molekulare Motoren herbeiführen kann. Ferner entwickeln wir eine generische Kontinuumsbeschreibung aktiver Filament-Systeme, die ausschließlich auf Symmetrien der Systeme beruht und von mikroskopischen Details unabhängig ist. Diese Theorie erlaubt uns eine komplementäre Sichtweise auf solche aktiven Filament-Systeme. Sie stellt ein wichtiges Werkzeug dar, um die physikalischen Mechanismen z.B. in Filamentbündeln aber auch bei der Bildung von Filamentringen im Zellkortex zu untersuchen. Schließlich entwickeln wir eine auf einem Kräftegleichgewicht basierende Beschreibung für bipolare Strukturen aktiver Filamente und wenden diese auf die mitotische Spindel an. Wir diskutieren Bedingungen für die Bildung und Stabilität von Spindeln
Active filament systems such as the cell cytoskeleton represent an intriguing class of novel materials that play an important role in nature. The cytoskeleton for example provides the mechanical basis for many central processes in living cells, such as cell locomotion or cell division. It consists of protein filaments, molecular motors and a host of related proteins that can bind to and cross-link the filaments. The filaments themselves are semiflexible polymers that are typically several micrometers long and made of several hundreds to thousands of subunits. The filaments are structurally polar, i.e. they possess a directionality. This polarity causes the two distinct filament ends to exhibit different properties regarding polymerization and depolymerization and also defines the direction of movement of molecular motors. Filament polymerization as well as force generation and motion of molecular motors are active processes, that constantly use chemical energy. The cytoskeleton is thus an active gel, far from equilibrium. We present theories of such active filament systems and apply them to geometries reminiscent of structures in living cells such as stress fibers, contractile rings or mitotic spindles. Stress fibers are involved in cell locomotion and propel the cell forward, the mitotic spindle mechanically separates the duplicated sets of chromosomes prior to cell division and the contractile ring cleaves the cell during the final stages of cell division. In our theory, we focus in particular on the role of filament polymerization and depolymerization for the dynamics of these structures. Using a mean field description of active filament systems that is based on the microscopic processes of filaments and motors, we show how filament polymerization and depolymerization contribute to the tension in filament bundles and rings. We especially study filament treadmilling, an ubiquitous process in cells, in which one filament end grows at the same rate as the other one shrinks. A key result is that depolymerization of filaments in the presence of linking proteins can induce bundle contraction even in the absence of molecular motors. We extend this description and apply it to the mitotic spindle. Starting from force balance considerations we discuss conditions for spindle formation and stability. We find that motor binding to filament ends is essential for spindle formation. Furthermore we develop a generic continuum description that is based on symmetry considerations and independent of microscopic details. This theory allows us to present a complementary view on filament bundles, as well as to investigate physical mechanisms behind cell cortex dynamics and ring formation in the two dimensional geometry of a cylinder surface. Finally we present a phenomenological description for the dynamics of contractile rings that is based on the balance of forces generated by active processes in the ring with forces necessary to deform the cell. We find that filament turnover is essential for ring contraction with constant velocities such as observed in experiments with fission yeast

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23

Nelson, T. "Integrating action research and journey making during real-world organizational strategy development." Thesis, University of Strathclyde, 2003. http://oleg.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=21248.

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Information systems (IS) researchers and practitioners have for some time now been advocating the use of Action Research as an appropriate means of undertaking work in the field of information systems (Checkland and Scholes, 1990; Mansell, 1991; Stowell and West, 1994; Baskerville and Wood-Harper, 1996,1998; Stowell, West and Stansfield, 1997; Checkland and Holwell, 1998, West and Stansfield, 2001; Mumford, 2001). Yet little has been written about the application of Action Research during the real-world development of organizational strategic plans, where an important aim of the Action Researcher is also the attainment of an academic qualification. A possible explanation for this may be the amount of controversy that still surrounds the theoretical principles (Cady and Caster, 2000) and the practice and application (Stowell et. al, 1997) of Action Research. In particular, Action Research has been criticised for producing research with little action or action with little research (Foster, 1972), lacking in the rigor of true scientific research (Cohen and Manion, 1980), lacking in validity of data (Baskerville and Wood-Harper, 1996), lacking in internal and external control (Merriam and Simpson, 1984) and likely to be a problematic research method for doctoral students (Eden and Huxham, 1993,1995,1996). This doctoral research programme has been set up to investigate two 'themes'. The first, of more research/academic interest, concerns the development and testing of a diagrammatic Action Research Approach that will help to ensure the delivery of valid/robust research results. Also, because most existing diagrams don't describe Action Research at a more useful lower 'micro' level (Lau, 1997). The second research theme, of more practical interest, concerns understanding what can happen when a 'novice' practitioner attempts to use Action Research and JOURNEY Making (Eden and Ackermann, 1998) to solve a real-world organizational strategic problem. To ensure that the research is seen as 'valid' Action Research, Checkland and Holwell's (1998) 'FMA' model is applied because "This is the intellectual structure which will lead to findings and research lessons being recognised as such. Without that declaration, it is difficult to see how the outcome of Action Research can be more than anecdotal" (p. 13-14).

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24

Toh, Peng Seng. "Three-dimensional reconstruction by active integration of visual cues." Thesis, Imperial College London, 1990. http://hdl.handle.net/10044/1/46581.

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25

Fazlollahi, Ariyan. "Benefits of Enterprise Integration Systems." Thesis, KTH, Industriella informations- och styrsystem, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-98486.

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Today, with various technology and business standards, organizations face rapid changes in both internal and external environments. To be able to rapidly respond to such changing environments, integration of software systems has entered among the top priorities of many organizations. However, despite extended use of software integration, methods for estimating the business value of implementing such integration are still missing. Besides presenting a conceptual model to define the benefits of systems integration and related causal relationships, this study proposes a method for measuring such benefits in monetary terms. In particular, we demonstrate how a mathematical programming technique called Data Envelopment Analysis (DEA) can be used to evaluate the business value of software integration. Our method is illustrated using data from 12 organizations. The results indicate significant productivity gains by integrating software systems, which represent the value of software integration in organizations.

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26

Ertem, Turker. "Asymptotic Integration Of Dynamical Systems." Phd thesis, METU, 2013. http://etd.lib.metu.edu.tr/upload/12615405/index.pdf.

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In almost all works in the literature there are several results showing asymptotic relationships between the solutions of x&prime
&prime
= f (t, x) (0.1) and the solutions 1 and t of x&prime
&prime
= 0. More specifically, the existence of a solution of (0.1) asymptotic to x(t) = at + b, a, b &isin
R has been obtained. In this thesis we investigate in a systematic way the asymptotic behavior as t &rarr
&infin
of solutions of a class of differential equations of the form (p(t)x&prime
)&prime
+ q(t)x = f (t, x), t &ge
t_0 (0.2) and (p(t)x&prime
)&prime
+ q(t)x = g(t, x, x&prime
), t &ge
t_0 (0.3) by the help of principal u(t) and nonprincipal v(t) solutions of the corresponding homogeneous equation (p(t)x&prime
)&prime
+ q(t)x = 0, t &ge
t_0. (0.4) Here, t_0 &ge
0 is a real number, p &isin
C([t_0,&infin
), (0,&infin
)), q &isin
C([t_0,&infin
),R), f &isin
C([t_0,&infin
) ×
R,R) and g &isin
C([t0,&infin
) ×
R ×
R,R). Our argument is based on the idea of writing the solution of x&prime
&prime
= 0 in terms of principal and nonprincipal solutions as x(t) = av(t) + bu(t), where v(t) = t and u(t) = 1. In the proofs, Banach and Schauder&rsquo
s fixed point theorems are used. The compactness of the operator is obtained by employing the compactness criteria of Riesz and Avramescu. The thesis consists of three chapters. Chapter 1 is introductory and provides statement of the problem, literature review, and basic definitions and theorems. In Chapter 2 first we deal with some asymptotic relationships between the solutions of (0.2) and the principal u(t) and nonprincipal v(t) solutions of (0.4). Then we present existence of a monotone positive solution of (0.3) with prescribed asimptotic behavior. In Chapter 3 we introduce the existence of solution of a singular boundary value problem to the Equation (0.2).

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27

Jones, A. H. "Integration of multiple sensor systems." Thesis, University of Cambridge, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.383191.

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28

MOREIRA, MARCOS MAGALHAES. "SEMANTIC INTEGRATION OF INFORMATION SYSTEMS." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2003. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=4421@1.

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Propõe-se neste trabalho uma abordagem para a integração semântica de informações baseada na linguagem de ontologia OWL, utilizada como linguagem padrão para tornar compatíveis as diversas fontes de informação. Incialmente, apresenta-se o problema de integração de informações e discute-se a aplicação de ontologia para resolvê-lo. Em seguida, indentificam-se as formas de obtenção e extração de ontologias , com ênfase em sistemas de bancos de dados. Da mesma forma, propõem-se alternativas para mapeamento entre classes , propriedades e instâncias das ontologias obtidas. Finalmente, desenvolve-se um estudo de caso para aplicação e validação das idéias apresentadas. Como resultado, propõe-se uma arquitetura de um sistema integrador e discute-se a implementação de alguns dos seus componentes.
This work presents a semantic approach to information integration based on the OWL ontology language, proposed as a standard language to facilitate the integration of different information sources. The information integration problem is first presented and then the use of ontologies to solve it is addressed. Then, strategies to obtain and extract ontologies are identified, emphasizing database system. Alternative mappings between classes , properties and instances of the resulting ontologies are also proposed.Finally, a case study is developed to apply and validate the strategies presented. As a result, an integrator system architecture is proposed and the implementation of some of its components is discussed.

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29

Hassan, Samy Aly. "Fundamental studies of passive, active and semi-active automotive suspension systems." Thesis, University of Leeds, 1986. http://etheses.whiterose.ac.uk/2691/.

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The fundamental properties of various automotive suspension systems are theoretically investigated on the basis of simple vehicle models subjected to realistic inputs chosen to represent road surfaces of different qualities. The vehicle response is evaluated through a performance index representing ride comfort, dynamic tyre load and suspension working space parameters, and interpreted in the light of these individual parameters together with the implications of the suspension design for attitude control and steering behaviour. Linear analysis procedures are followed in studying the passive, active and slow-active suspension systems while suitable simulations are used for the non-linear semi-active suspension systems. Linear optimal control theory is used to determine the optimal parameters of the active and slow-active suspension systems. Semi-active suspension behaviours are evaluated on the basis of applying the optimal active parameters to each system, but the semi-active damper can only dissipate energy and switches off when external power would be needed for the system to follow the optimal active control law. Results are generated and discussed for each of these types of system and their performance capabilities are compared with each other. Conclusions concerning the practical viability of each of the systems are drawn.

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30

Jeppesen, B. P. "Enhancing safety in active suspension systems." Thesis, University of Cambridge, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.605592.

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Chapter 3 describes how a distributed control system architecture was designed, to fulfil the functional specification required of the vehicle. A safety review was performed on the conceptual design, which identified requirements for the control software and the need for an independent safe-shutdown system. The choice of hardware and a software development system for the co-ordinating Global Controller is described. The deign of the safe shutdown system is detailed. A multi-mode software structure is defined. Chapter 4 discusses the principles of fault detection, and their application in cases of ‘direct redundancy’. The logic required for voting systems, using identical sensors, is extended to the case of sensors whose measurements can be related instantaneously, for example using kinetics. Suitable sets of sensors on the experimental vehicle are identified, and test results are presented. Chapter 5 shows how fault detection can be made more precise by using dynamic models, rather than instantaneous relationships, to relate sensor measurements. The techniques are applied by dividing the experimental vehicle conceptually into subsystems. Identification of more subtle faults, including loss of suspension stiffness, is demonstrated.

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31

Truscott, A. J. "Control studies in active suspension systems." Thesis, University of Manchester, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.282524.

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32

Mills, P. G. L. "Active loudspeaker systems with transconductance amplification." Thesis, University of Essex, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.384776.

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33

Hediyeh, Zahabi. "Colour changing electro active polymer systems." Thesis, Queen Mary, University of London, 2017. http://qmro.qmul.ac.uk/xmlui/handle/123456789/24856.

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Dielectric elastomers are electroactive polymers, which change size and shape in response to an electrical field. Dielectric elastomer actuators (DEAs) are highly promising new technologies in optical applications such as tuneable optical lenses, diffraction gratings and active camouflage. This thesis aims to develop a new approach to create a strain actuated compliant colour changing device that is controlled using DEAs as they offer stretchability, low weight, high efficiency, low cost and the possibility for miniaturisation. Conventional DEAs use transparent elastomeric materials with no significant colour change with strain. Conversely, liquid crystal materials are known to display dynamic colour changing behaviour, thereby making them good candidate materials. The thesis examines both the potential for colour changing soft actuators and the upcoming challenges in this field as well as the key concepts around liquid crystals that exhibit colour change. An initial approach was aimed at creating colour changes using dielectric elastomer actuators that drove a masked positioner. This method showed colour change since the mask changes the colour visualisation. The second approach used polymer dispersed liquid crystals, such as a nematic liquid crystal within a reactive silicone resin. The immiscibility of these compounds resulted in a dispersion of the liquid crystal droplets in the silicone matrix. However, the optical properties could not be controlled through mechanical deformation alone and the alignment of resulting LC droplets in the PDLC films was sensitive to the substrate used to perform the actuation. The next approach used reactive cholesteric liquid crystals (CLC) instead. A thin film coating process was preferred to carefully control the film's thickness by stretching. In free standing films a planar cholesteric alignment was obtained with mesogens aligned parallel to the substrate and colour was achieved based on the selective reflection of light. A transfer print technique was introduced to combine CLC coatings with elastomeric substrates that can be stretched. However, no colour change was achieved in response to mechanical deformation primarily due to the modulus and strength mismatch between the thin film and the elastomeric susbstrate material. Finally, lightly crosslinked liquid crystal elastomers using a combination of reactive and non-reactive liquid crystals were produced that were compatible with elastomer substrate materials. In free standing films planar cholesteric alignment was obtained with mesogens aligned parallel to the substrate. Successfully a reversible colour change based on selective reflection of light was achieved in response to a mechanical deformation.

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34

Haribabu, Aravind Saravanan. "Active Interaction Complexity in Systems Engineering." Thesis, KTH, Skolan för industriell teknik och management (ITM), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-301619.

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The master's thesis describes how complexity measurement can enhance product development or design processes in collaboration with Scania CV AB. Scania has a strong track record in vehicle modularization and thus wanted to investigate the possibility of using complexity measures when architecting, developing, and maintaining complex engineering products such as electrified or self-driving trucks and buses to gain various types of benefits. The section YMPI at Scania, where the project is conducted, had, however, little experience in complexity measurements wants to identify and investigate which complexity measure effectively captures the complexity of a complex system. A fairly complicated industrial case of a conceptual Battery Electric Vehicle (BEV) variant was utilized to demonstrate the newly proposed complexity metric methodology and demonstrate its ability to determine the technical complexity of a system. As a result, the thesis author found a specific case study at Scania and used appropriate methodologies to determine the complexity of the chosen subsystem using the newly proposed complexity measure. This was done by adapting the DSM (Design Structure Matrix) before clustering it with the IGTA++ clustering algorithm. The proposed complexity metric yields a higher complexity number when compared to the traditional product complexity metric. Another purpose of the thesis was to answer the research questions and conduct a literature review in the field of Model Based System Engineering and product architecting to define the state-of-the-art. The thesis concludes that the newly proposed complexity metric, when implemented on the chosen subsystem, yields a higher complexity number when compared to the number obtained from product complexity, implying that including the directions of an interaction between the components and taking into account the active interacting components improves the accuracy of the complexity measure. Therefore, it is recommended to Scania to use this proposed method to find the complexity of the system and to compare how the system gets complex when incorporating new technologies or modifying the system or product architecture, as well as to utilize this as a safety and a performance factor for a system.
I examensarbetet beskrivs hur komplexitetsmätning kan förbättra produktutvecklings- eller designprocesser i samarbete med Scania CV AB. Scania har en stark erfarenhet av fordonsmodularisering och önskade därför undersöka möjligheten att använda komplexitetsmått för arkitektur, utveckling och underhåll av komplexa tekniska produkter som elektrifierade eller självkörande lastbilar och bussar för att få olika typer av fördelar. Sektionen YMPI på Scania, där projektet genomförs, hade dock lite erfarenhet av komplexitetsmått och sökte identifiera och undersöka vilket komplexitetsmått som effektivt fångar komplexiteten hos ett komplext system. Ett ganska komplicerat industriellt fall av en konceptuell variant av ett elektriskt batterifordon (BEV) användes för att demonstrera den nyligen föreslagna metoden för komplexitetsmätning och för att visa dess förmåga att fastställa ett systems tekniska komplexitet. Som ett resultat av detta hittade avhandlingsförfattaren en specifik fallstudie hos Scania och använde lämpliga metoder för att bestämma komplexiteten hos det valda delsystemet med hjälp av det nyligen föreslagna komplexitetsmåttet. Detta gjordes genom att anpassa DSM (Design Structure Matrix) innan den klustrades med klusteralgoritmen IGTA++. Det föreslagna komplexitetsmåttet ger ett högre komplexitetstal jämfört med det traditionella produktkomplexitetsmåttet. Ett annat syfte med avhandlingen var att besvara forskningsfrågorna och genomföra en litteraturstudie inom området modellbaserad systemteknik och produktarkitektur för att definiera den senaste tekniken. I avhandlingen dras slutsatsen att det nyligen föreslagna komplexitetsmåttet, när det tillämpas på det valda delsystemet, ger ett högre komplexitetstal jämfört med det tal som erhålls från produktkomplexitet, vilket innebär att om man inkluderar riktningarna för en interaktion mellan komponenterna och tar hänsyn till de aktiva interagerande komponenterna förbättras komplexitetsmåttets noggrannhet. Därför rekommenderas Scania att använda den föreslagna metod för att fastställa systemets komplexitet och jämföra hur systemet blir mer komplext när ny teknik införlivas eller när system- eller produktarkitekturen ändras, samt att använda detta som en säkerhets- och prestandafaktor för ett system.

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35

Hassan, Marwa M. "Framework for active solar collection systems." Diss., Virginia Tech, 2003. http://hdl.handle.net/10919/28048.

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A framework that presents a new methodology for design-evaluation of active solar collection systems was developed. Although this methodology emphasizes the importance of detailed modeling for accurate prediction of building performance, it also presents a process through which the detailed modeling results can be reused in a simplified iterative procedure allowing the designer the flexibility of revising and improving the preliminary design. For demonstration purposes, the framework was used to design and evaluate two case studies located in Blacksburg (VA) and Minneapolis (MN). These locations were selected because they both represent a cold weather region; presenting a need for using solar energy for heating and hot water requirements. Moreover, the cold weather in Blacksburg is not as severe as in Minneapolis. Therefore, the two cases will result in different thermal loading structures enabling the framework validation process. The solar collection system supplying both case studies consisted of a low temperature flat plate solar collector and storage system. Thermal performance of the case study located in Blacksburg was conducted using detailed modeling evaluation techniques; while thermal performance of the case study located in Minneapolis was conducted using a simplified modeling evaluation technique. In the first case study, hourly evaluation of the thermal performance of the solar collection system was accomplished using finite element (FE) analysis, while hourly evaluation of the building thermal performance was made using Energy Plus software. The results of the finite element analysis were used to develop a statistical predictive design equation. The energy consumption for the second case study was calculated using the heating design day method and the energy collection for that case study was calculated using the predictive design equation developed from the first case study results. Results showed that, in the case of the building located in Blacksburg, the solar collection system can supply an average of 85% of the buildingâ s heating and hot water requirements through out the year. In the case of the building located in Minneapolis, the solar collection system can supply an average of 56% of the buildingâ s heating and hot water requirements through out the year given no night time window insulation and using similar insulation thicknesses for both cases.
Ph. D.

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36

Bergamini, Giacomo <1979&gt. "Photo-and redox-active supramolecular systems." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2007. http://amsdottorato.unibo.it/475/1/GBergaminiTesiXIXcicl.pdf.

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37

Bergamini, Giacomo <1979&gt. "Photo-and redox-active supramolecular systems." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2007. http://amsdottorato.unibo.it/475/.

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38

Carter, Joanna M. "Shipbuilding integration." Thesis, Monterey California. Naval Postgraduate School, 2005. http://hdl.handle.net/10945/1841.

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The build cycle of a first in class combat ship takes about six years. During that timeframe, systems are being designed, installed, and tested, but, until the ship is in the water and tested at sea trials, it is not known if the ship is fully integrated and will actually work. As time progresses, integration problems become harder and more expensive to solve. Every time a new system is added or upgraded, there may be interference from another system that was not anticipated. It is important to test and verify each system, but there is limited time and resources to do so. By successfully planning and performing systems integration at the correct time of the acquisition cycle, it is possible to reduce the chance of system failure. This thesis explains and establishes a process for designing and building a fully integrated combat ship by first defining systems integration for the customer and the shipbuilder and explaining why performing systems integration is important.

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39

García, Estébanez Jesús. "GPS-IMU Integration for a Snake Robot with Active Wheels." Thesis, Norwegian University of Science and Technology, Department of Engineering Cybernetics, 2009. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-9107.

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A snake robot will be defined herein as any multilink robot for whose shape and motion capabilities are reminiscent of a snake like PiKo [1]. PiKo is a five links snake robot with active wheels designed by SINTEF in collaboration with the Norwegian University of Science and Technology (NTNU). Researchers have been greatly interested in the development of robots like PiKo because of its shape versatility and motion capacity in difficult terrains. These skills and properties are useful for rescue teams working in earthquakes, pipe inspection operations and other utilities where access and movement in the terrain are typically difficult. When a working team decides to develop a snake robot, an important point to consider is the development of an efficient navigation system that reaches an accurate position of the robot. Technically speaking, it is prudent to design at the same time a state observer that gives us at least the real time position and velocity information of the robot body to be controlled. The relevance of this information is derived from every control action applied to the robot will require some information about the situation of the robot over time. The controller will need feedback about the robot dynamics and the effect that the control actions have caused. Typically this information has three sources: the information that comes from external sensors, that from internal sensors that transmitting to the control place the measurements from the sensors in the robot body and estimated data from a physical model. All of these feedback sources have some advantages and disadvantages. Implementing an external observer, with external sensors, will not cause space problem with sensors location in the robot body, but when the robot is working inside a pipe, underground or in another hard environment where the optical, magnetic or radio frequency contact is difficult or impossible, the information reception from an external observer is too difficult and expensive or simply impossible. Locating internal sensors in the body of the robot may solve has the problem with the measurements reception, but still pose some difficulties which must be considered by the designer. Many times space becomes a problem when locating some sensors inside the robot body due to size and weight constraints within the robot body. Basing the navigation system instead on a physical model that simulates the robot motion invites the possibility of error due to simplifications taken during the mathematical and physical development. It is impossible to develop a perfect physical model since all the variables, forces, and parameters that depend on the nature characteristics usually are random process and we can just raise a useful factor estimating the average of these effects in our concrete situation. In this thesis a navigation system with a GPS (Global Positioning System) and IMU (Inertial Measurement Unit) fusion was achieved. This navigation system will be work as long the GPS signal is available. The application of the fusion technique further reduces one order the potential errors inherent in using only the GPS navigation system. When the robot will encounter locations where the GPS signal is impossible, this thesis will present a set of tools that not being a universal solution, it will be a set of mathematical tools that depending on the case could give us an accurate navigation system. During the time the GPS signal reception is impossible, this thesis presents the development and implementation of a physical model for a snake robot with active wheels which simulates the snake robot running behavior and studies the possibility to use the trajectory estimated by the model for reaching an accurate navigation system.

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40

Lyall, Evan Harrison. "Surround Integration During Active Sensation in the Mouse Barrel Cortex." Thesis, University of California, Berkeley, 2019. http://pqdtopen.proquest.com/#viewpdf?dispub=13422798.

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Анотація:

Organisms scan their sensors around their environment to build an internal representation of that environment in a process known as active sensation. The integration of information across time and space is critical to providing context as to what is the organism is perceiving. However, the neural circuits that encode and underlie the integration of incoming sensory information have predominantly been studied in the context of passive sensation. Studying these circuits in the context of active sensation is imperative to generating a better understanding of how the brain naturally encodes sensation. This would have profound impacts on understanding the mechanisms of a number of neural disorders, including autism and attention-deficit/hyperactivity disorder, as well as how to improve the acuity of artificial sensation implanted into disabled individuals. To better understand how the mammalian brain encodes and integrates information during active sensation, my collaborators and I developed several novel paradigms to study surround integration in the mouse barrel cortex during active whisking. In Chapter 1 I establish why this is an important problem, and briefly summarize what is already known about sensory coding in the mouse whisker system. In Chapter 2 my collaborators and I probe how mice represent the location of an object within its whisking field, and how the integration of information across surround whiskers affects this representation. In doing so we discover a novel thalamocortical transformation where surround integration in the cortex suppresses activity in layer 4 of the cortex, ultimately generating a smooth map of scanned space in cortical layer 2/3. In Chapter 3 I utilize a novel tactile display to better understand the logic of multi-whisker integration in two cortical layers. In this unpublished work, I show that contrary to the previous literature in anesthetized mice, cortical neurons in awake, whisking mice powerfully summate specific whisker combinations supralinearly, generating a sparse code representing the entire combinatoric space of whisker touch. In Chapter 4, I conclude with some closing thoughts and propose some future lines of inquiry to further this research.

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41

Girlevicius, Lukas. "Active magnetic bearing driver circuit design featuring current measurement integration." Thesis, Uppsala universitet, Elektricitetslära, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-269215.

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Researchers at Uppsala University are developing a flywheel energy storage device intended to be used in electrical vehicles. Kinetic energy storage technology has potential to make purely electric powertrain both more effective and efficient. While deployment of the third prototype is approaching there has been a request for a more precise and noise-immune circuitry to power active magnetic bearings that hold and stabilise the rotor. A similar circuit designed for powering electromagnets was recently developed at the Uppsala University’s Electricity department and is used as a template in development of the new active magnetic bearing driver circuit. Current measurement integration technique is tested and implemented as a way to increase circuit’s control feedback loop performance. To further boost precision and noise-immunity 0-20 mA current loop signals are adapted as the standard for output signals. Results of this project include a thorough analysis of the electromagnet driver circuit development, implementation of a new current sensing technique including an experimental self-inductance measurement, printed circuit board layout design and a full list of components necessary to power and control two sets of active magnetic bearings consisting of 8 individual electromagnets.

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42

Becker, Gina M. D. "Human Systems Integration Competency Development for Navy Systems Commands." Thesis, Monterey, California. Naval Postgraduate School, 2012. http://hdl.handle.net/10945/17322.

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Анотація:

Approved for public release; distribution is unlimited
There is a growing need in defense acquisition to design timely, cost-effective competency development programs to facilitate qualifying new hires to replace a rapidly aging workforce. Navy Systems Commands (SYSCOMs), which are charged with system acquisition and sustainment, are engaged in Total Force Management strategies to support technical competency, development, and qualifications. This thesis examined a Competency Development Model constructed by Space and Naval Warfare Systems Command subject matter experts for Human System Integration (HSI) practitioners at four levels of their careers. The notional meta-competencies required by HSI practitioners were initially reviewed by 10 senior HSI acquisition professionals (representing each of the three major Navy SYSCOMs) and then 24 frontline supervisors to align them with the appropriate acquisition domain, validate the proper practitioner work level where the meta-competency was required, and identify the potential sources for meta-competency development. The results were then compiled for supervisory use in supporting HSI practitioner career development. In addition, an Individual Development Plan for front-line supervisors was constructed to support entry-level HSI employee development. It is asserted that this process can be used by other SYSCOM engineering competencies to identify requisite meta-competencies for practitioner career development and qualification.

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43

Leimkuhler, Benedict, and Sebastian Reich. "Symplectic integration of constrained Hamiltonian systems." Universität Potsdam, 1994. http://opus.kobv.de/ubp/volltexte/2007/1565/.

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A Hamiltonian system in potential form (formula in the original abstract) subject to smooth constraints on q can be viewed as a Hamiltonian system on a manifold, but numerical computations must be performed in Rn. In this paper methods which reduce "Hamiltonian differential algebraic equations" to ODEs in Euclidean space are examined. The authors study the construction of canonical parameterizations or local charts as well as methods based on the construction of ODE systems in the space in which the constraint manifold is embedded which preserve the constraint manifold as an invariant manifold. In each case, a Hamiltonian system of ordinary differential equations is produced. The stability of the constraint invariants and the behavior of the original Hamiltonian along solutions are investigated both numerically and analytically.

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44

Hadjimichael, Basil. "Manufacturing execution systems integration and intelligence." Thesis, McGill University, 2005. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=82491.

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In order to survive in today's competitive manufacturing markets, manufacturing systems need to adapt at an ever-increasing pace to incorporate new technology which can lower the cost of production, while maintaining quality and delivery schedules. The task of the manufacturing system becomes even more challenging in the quest to use a common approach for different manufacturing plants and ever evolving manufacturing processes for specific plants. This thesis introduces a reference architecture that enables such changes between plants and updates within plants. For this, we use the paradigm of Manufacturing Execution Systems (MES). A developed MES architecture by the National Institute of Standards and Technology (NIST) is used as the standard reference architecture. Its flexibility and scalability is applied to a specific steel melt-shop plant case study. In this case study the standard framework is specified through re-labeling standard data and modules to specifics tailored for the melt process of a generic steel plant. Since steel plants are faced with difficult scheduling and disturbance handling problems, specific intelligent algorithms are developed to deal with these issues through integrating some of the control into the MES. Conclusions as to the success of the algorithms along with supporting data and recommendations of further use for them are also included.

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45

Tvaryanas, Anthony P. "A discourse in human systems integration." Monterey, California. Naval Postgraduate School, 2010. http://hdl.handle.net/10945/10571.

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This dissertation tackles, head on, two fundamental questions: What is human systems integration (HSI) and how should one think about HSI problems? The objective was to develop a coherent systems method to improve the integration of HSI domains to create sustainable systems while preserving system stakeholder preferences. This dissertation addresses these questions by accomplishing two things: 1) extracting the lessons learned from a historical analysis of the emergence of HSI both as a philosophy and as a Defense Department program, and 2) using those lessons to characterize and illustrate a technical approach to addressing HSI considerations early in an acquisition process. It is shown that the discourse on general systems that occurred over the latter half of the twentieth century, coupled with pressing organizational factors within the U.S. Army, were the principal forces that shaped and drove the emergence and formal recognition of HSI. As determined from this historical analysis, HSI involves the integration of the behavioral sciences, human factors engineering, and operations research to more broadly represent human considerations in early weapon system analyses and the products that evolve from these analyses. Inclusion of HSI in system analyses necessitates a holistic perspective of the performance and economic trade space formed by the synthesis of the HSI domains. As a result, individual domain interventions are considered in terms of tradeoff decisions. Ideally, the HSI trade space can be systematically explored by integrating Simon's research strategy, Kennedy and Jones' isoperformance approach, and coupling isoperformance with utility analysis through means such as physical programming. Although domain tradeoffs are a central element of HSI, very few studies illustrate the integration of the behavioral sciences and human factors engineering with the tools and methodologies of operations research. Accordingly, three case studies are presented: a preexisting opportunistic dataset of potential Air Force unmanned aircraft pilots, a prospective dataset of Army Soldiers in Basic Combat Training, and data derived from simulation of staffing and shift scheduling solutions using a biomathematical model. Lastly, guidelines for a New HSI method and future challenges are discussed.

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46

Lohith, Penmetsa Neela. "Monolithic 3D integration of asynchronous systems." Thesis, Georgia Institute of Technology, 2014. http://hdl.handle.net/1853/53113.

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The goal of this thesis is to study the impact of 3D integration on asynchronous circuits and explore the benefits in power, performance and area compared to traditional two dimensional integration. To enable this study we develop a fully automated asynchronous design methodology and 3D integration flows for asynchronous circuits. This study is also a first one to explore the mutual benefits of asynchronous circuits and 3D integration.

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47

Liu, Kevin K. (Kevin Kaitan) 1986. "Cost estimation of human systems integration." Thesis, Massachusetts Institute of Technology, 2010. http://hdl.handle.net/1721.1/59776.

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Thesis (S.M. in Technology and Policy)--Massachusetts Institute of Technology, Engineering Systems Division, 2010.
Cataloged from PDF version of thesis.
Includes bibliographical references (p. 103-108).
Human Systems Integration (HSI) is the interdisciplinary technical and management processes for integrating human considerations within and across all system elements. The goal of this research is to develop a better understanding of how the costs of doing HSI work within a program can be estimated. The research is divided into two parts. In the first part, problem formulation, literature from several relevant domains is first reviewed. Next a descriptive case study is conducted on the development of the Pratt and Whitney F 119 engine. It examines activities done to support HSI up to engineering and manufacturing development and concludes that, among other factors, HSI in requirements are a major driver of effort. This conclusion leads to work on the integration of HSI into the counting of requirements for an existing systems engineering cost model. In the second part of the research, implementation and validation, two workshops are conducted to assess how HSI considerations are addressed in real-world requirements engineering. The first workshop tests existing requirements counting guidelines, identifies weakness, and suggests improvement. The second workshop applies the Wideband Delphi method to generate consensus between stakeholders in order to deliver a quantitative estimate of HSI effort. The workshop also demonstrates that stakeholders perceive functional and nonfunctional requirements as driving effort in similar ways, a conclusion that challenges a widely-held belief that nonfunctional requirements are less significant than functional ones. The research done in the case study and workshops results in improvements to the existing systems engineering cost model, and an application of the model is presented. Policy considerations are discussed. The integration of the HSI into the model represents a significant step toward being better able to plan HSI effort in acquisition programs.
by Kevin K. Liu.
S.M.in Technology and Policy

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Quiram, David J. "Characterization and systems integration of microreactors." Thesis, Massachusetts Institute of Technology, 2001. http://hdl.handle.net/1721.1/8272.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Chemical Engineering, February 2002.
Includes bibliographical references.
Microfabrication technology presents the opportunity to create highly instrumented, micro-scale chemical reactors that bring with them the potential for new analytical capabilities, point-of-use synthesis, and highly parallel screening methods. However, the use of integrated circuit-like reaction devices, such as the MIT thin-film microreactor, also gives rise to a spectrum of new engineering challenges with respect to reactor system integration and scale-up schemes. This work demonstrates the integration of multiple microreactors operating in parallel within a system that includes gas flow control components and the associated electronic circuitry. The system built is equivalent to a conventional laboratory reactor system but in 1/10th of the space. Fluidic and electronic interfaces, thermal management, and operational safety are all considerations in microreactor packaging. A standard microchip socket from Texas Instruments was selected as the first level packaging. The sockets have mechanical attributes that lend them to, with minor reworking, simultaneous fluidic and electronic connection. This selection makes PC board mounting of the reactor devices straightforward. Shut-off microvalves and proportional microvalves from Redwood Microsystems, with their control electronics, have also been mounted on PC boards to control the gas flow in the system. This allows the entire system: reactors, device electronics, and gas distribution manifold to be mounted on standard CompactPCI cards and housed in a commercially available chassis. A Kaparel CompactPCI chassis is used to house the microreactor system.
Electrical connections between the boards are achieved through a standard backplane and custom-built rear I/O PC boards. The system is comprised of a temperature controller card that regulates temperature for auxiliary heaters in the system; a gas mixing board that mixes the feed gas for the microreactors; two microreactor boards that each contain two microreactors with their feed flow controllers; and two heater circuit boards that provide power to the microreactor heaters. A National Instruments embedded real time processor is used to provide closed-loop control and monitor system alarms. A host PC, running LabVIEW 6, is used as the human machine interface for operator interaction and historical data logging.
by David J. Quiram.
Ph.D.

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49

Faltinsen, Stig. "Geometric integration of lie-poisson systems." Thesis, University of Cambridge, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.621090.

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50

Minich, Matthias Ernst. "Industrialising software development in systems integration." Thesis, University of Plymouth, 2013. http://hdl.handle.net/10026.1/2772.

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Compared to other disciplines, software engineering as of today is still dependent on craftsmanship of highly-skilled workers. However, with constantly increasing complexity and efforts, existing software engineering approaches appear more and more inefficient. A paradigm shift towards industrial production methods seems inevitable. Recent advances in academia and practice have lead to the availability of industrial key principles in software development as well. Specialization is represented in software product lines, standardization and systematic reuse are available with component-based development, and automation has become accessible through model-driven engineering. While each of the above is well researched in theory, only few cases of successful implementation in the industry are known. This becomes even more evident in specialized areas of software engineering such as systems integration. Today’s IT systems need to quickly adapt to new business requirements due to mergers and acquisitions and cooperations between enterprises. This certainly leads to integration efforts, i.e. joining different subsystems into a cohesive whole in order to provide new functionality. In such an environment. the application of industrial methods for software development seems even more important. Unfortunately, software development in this field is a highly complex and heterogeneous undertaking, as IT environments differ from customer to customer. In such settings, existing industrialization concepts would never break even due to one-time projects and thus insufficient economies of scale and scope. This present thesis, therefore, describes a novel approach for a more efficient implementation of prior key principles while considering the characteristics of software development for systems integration. After identifying the characteristics of the field and their affects on currently-known industrialization concepts, an organizational model for industrialized systems integration has thus been developed. It takes software product lines and adapts them in a way feasible for a systems integrator active in several business domains. The result is a three-tiered model consolidating recurring activities and reducing the efforts for individual product lines. For the implementation of component-based development, the present thesis assesses current component approaches and applies an integration metamodel to the most suitable one. This ensures a common understanding of systems integration across different product lines and thus alleviates component reuse, even across product line boundaries. The approach is furthermore aligned with the organizational model to depict in which way component-based development may be applied in industrialized systems integration. Automating software development in systems integration with model-driven engineering was found to be insufficient in its current state. The reason herefore lies in insufficient tool chains and a lack of modelling standards. As an alternative, an XML-based configuration of products within a software product line has been developed. It models a product line and its products with the help of a domain-specific language and utilizes stylesheet transformations to generate compliable artefacts. The approach has been tested for its feasibility within an exemplarily implementation following a real-world scenario. As not all aspects of industrialized systems integration could be simulated in a laboratory environment, the concept was furthermore validated during several expert interviews with industry representatives. Here, it was also possible to assess cultural and economic aspects. The thesis concludes with a detailed summary of the contributions to the field and suggests further areas of research in the context of industrialized systems integration.

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