Дисертації з теми "SPICE Implementation"
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1
Bonhomme, Phillip. "Circuit modeling of spintronic devices: a SPICE implementation." Thesis, Georgia Institute of Technology, 2014. http://hdl.handle.net/1853/51818.
Повний текст джерелаАнотація:
Every engineer that has worked on designing an integrated circuit has to leverage an under- standing of device physics. Understanding device physics is essential when optimizing a design for speed, power, etc. These characteristics affect the bottom line when considering an integrated circuit used in a particular application. In order for there to be an under- standing of device physics, there must be a device model that is developed for a device of interest. The development of a device model often involves utilizing fundamental physical equations in a manner that is solvable by either analytical or numerical means.
This typically begins by simplifying fundamental physical equations, possibly spanning multiple domains, and considering the physical quantities of interest. In order to make simplifications, assumptions about the underlying physics must be made. It is the process of transitioning from known physics laws to simplified mathematical models that a device modeler spans.
This thesis will cover the device modeling aspects of a new classification of computing devices, spintronics. It will begin by stating the physical assumptions necessary for the operation of spintronic devices. Then it will go the process of deriving the underlying physical equations and stating them in a tractable form with the appropriate boundary conditions. Then these equations will be manipulated and mapped into an equivalent circuit. The equivalent circuits will them be validated against analytical solutions provided from other works. It will then finish by providing example devices that can be simulated with the develop device models, and some optimization results are proposed based off a simplified circuit model.
2
Angel, Nathan A. "EQUIVALENT CIRCUIT IMPLEMENTATION OF DEMYELINATED HUMAN NEURON IN SPICE." DigitalCommons@CalPoly, 2011. https://digitalcommons.calpoly.edu/theses/611.
Повний текст джерелаАнотація:
This work focuses on modeling a demyelinated Hodgkin and Huxley (HH) neuron with Simulated Program with Integrated Circuit Emphasis (SPICE) platform. Demyelinating disorders affect over 350,000 people in the U.S and understanding the demyelination process at the cellular level is necessary to find safe ways to treat the diseases [9]. Utilizing a previous SPICE model of an electrically small cell neuron developed by Szlavik [32], an extended core conductor myelinated neuron was produced in this work. The myelinated neuron developed has seven active Nodes of Ranvier (nodes) separated by a myelin sheath. The myelin sheath can be successfully modeled with a resistive and capacitive network known as internodes. Both the Nodes of Ranvier and internode equivalent circuits were implemented in P-SPICE sub-circuit library files. Properties of the neuron can be changed in the library files to simulate neurons of different electrical or geometric properties. Using the P-SPICE code developed in this work, a myelinated neuron’s action potential was simulated and the action potential at each node was recorded. The action potential at each node was uniform in amplitude and pulse width. The conduction velocity of the action potential was calculated to be 57.15 m/s.
Demyelination can be modeled by decreasing the capacitance and increasing the resistance of the myelin [34]. Two demyelinated neuron models were simulated in this work. The first model had one internode segment demyelinated, and the second model was of three consecutive internode segments. The resulting conduction velocity was calculated for both simulations. For one and three internode segment demyelinated the conduction velocity was slowed to 44.15 m/s, and 27.15 m/s respectively. This model successfully showed that an HH neuron implemented in SPICE could show the effects of demyelination on conduction velocity
The goal of this work is to develop a demyelinated neuron so that treatments for Multiple Sclerosis (MS) and other demyelinated neurons could be simulated to test various treatments’ effectiveness. A current treatment for MS is ion channel blockers. Future work would be to use this model to test current ion channel blocker therapy and to validate if such therapies alleviate conduction slowing.
3
Tegethoff, Mauro Viana. "IMPLEMENTATION OF THE WAVEFORM RELAXATION ALGORITHM BASED ON CHEBYSHEV POLYNOMIALS IN SPICE." Thesis, The University of Arizona, 1985. http://hdl.handle.net/10150/275391.
Повний текст джерела
4
Manda, Malleswar. "Modeling of self heating effects in hetrojunction bipolar transistors and implementation in spice software." Ohio : Ohio University, 1996. http://www.ohiolink.edu/etd/view.cgi?ohiou1178213156.
Повний текст джерела
5
Nemesure, Gregg, and Brian Safigan. "A SPACE LINK EXTENSION IMPLEMENTATION FOR INTEGRAL." International Foundation for Telemetering, 2001. http://hdl.handle.net/10150/606476.
Повний текст джерелаАнотація:
International Telemetering Conference Proceedings / October 22-25, 2001 / Riviera Hotel and Convention Center, Las Vegas, NevadaCCSDS recommendations initially addressed the communication link between spacecraft and ground station. Space Link Extension (SLE) is a set of CCSDS recommended standards for extending the link to control centers, allowing distributed access to space link telecommand and telemetry services. The recommendations encompass the specification of both services and access methods. This paper discusses an implementation of SLE that will be used to provide Forward CLTU service to the upcoming INTEGRAL (International Gamma Ray Astrophysics Laboratory) mission.
6
Prelipcean, Adrian Corneliu. "Implementation and evaluation of Space Time Alarm Clock." Thesis, KTH, Geodesi och geoinformatik, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-157533.
Повний текст джерелаАнотація:
Many modern mobile communication devices are equipped with a GPS receiver and anavigation tool. These devices are useful when a user seeks to reach a specified destinationas soon as possible, but may not be so when he/she only needs to arrive at thedestination in time and wants to focus on some activities on the way. To deal with thislatter situation, a method and device called “Space Time Alarm Clock” is presented forhelping the user reach the destination by a specified deadline and inform the user aboutthe consequences of his/her decisions. It does so by continuously and efficiently computinghow much more time the user may stay at his/her current location without failing toreach the destination by the deadline. Furthermore, it determines the possible movementchoices that a user can make with regards to an underlying road network, it computesthe shortest travel time associated with each choice and informs the user about the consequencesof his/her decisions. Advantage of this approach is that it works completelyin the background so that the user‘s en-route activities will never be interfered with. The“Space Time Alarm Clock” was implemented for Stockholm, where it was tested.
7
Honorato, Mauro Jacob. "Wam based space efficient Prolog implementation in Lisp." Universidade Federal de Uberlândia, 2015. https://repositorio.ufu.br/handle/123456789/17800.
Повний текст джерелаАнотація:
Esse trabalho propõe a implementação de um sistema Prolog eficiente no
espaço, o mesmo é baseado nos trabalhos de David H. D. Warren e Hassan
Aït-Kaci. A Common Lisp é a estrutura usada para a construção do sistema
Prolog, ela foi escolhida tanto por fornecer um ambiente eficiente no espaço
quando por ser uma linguagem de programação rica no sentido de que fornece
ao usuário abstrações e novas maneiras de pensar. O sistema resultante
consiste em uma nova sintaxe aplicada à linguagem inicial que funciona sobre
a implementanção Common Lisp chamada SBCL e é capaz de abstrair ou
explorar o sistema subjacente.This thesis proposes the implementation of a space efficient Prolog implementation based on the work of David H. D. Warren and Hassan Aït-Kaci. The Common Lisp is the framework used to the construction of the Prolog system, it was chosen both to provide a space efficient environment and a rich programming language in the sense that it supply the user with abstractions and new ways of thinking. The resulting system is a new syntax to the initial language that runs on top of the SBCL Common Lisp implementation and can abstract away or exploit the underlying system.
Tese (Doutorado)
8
Capizzi, Sirio <1980>. "A tuple space implementation for large-scale infrastructures." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2008. http://amsdottorato.unibo.it/914/1/Tesi_Capizzi_Sirio.pdf.
Повний текст джерелаАнотація:
Coordinating activities in a distributed system is an open research topic. Several models have been
proposed to achieve this purpose such as message passing, publish/subscribe, workflows or tuple
spaces. We have focused on the latter model, trying to overcome some of its disadvantages. In
particular we have applied spatial database techniques to tuple spaces in order to increase their
performance when handling a large number of tuples. Moreover, we have studied how structured
peer to peer approaches can be applied to better distribute tuples on large networks. Using some of
these result, we have developed a tuple space implementation for the Globus Toolkit that can be
used by Grid applications as a coordination service. The development of such a service has been
quite challenging due to the limitations imposed by XML serialization that have heavily influenced
its design. Nevertheless, we were able to complete its implementation and use it to implement two
different types of test applications: a completely parallelizable one and a plasma simulation that is
not completely parallelizable. Using this last application we have compared the performance of our
service against MPI. Finally, we have developed and tested a simple workflow in order to show the
versatility of our service.
9
Capizzi, Sirio <1980>. "A tuple space implementation for large-scale infrastructures." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2008. http://amsdottorato.unibo.it/914/.
Повний текст джерелаАнотація:
Coordinating activities in a distributed system is an open research topic. Several models have been
proposed to achieve this purpose such as message passing, publish/subscribe, workflows or tuple
spaces. We have focused on the latter model, trying to overcome some of its disadvantages. In
particular we have applied spatial database techniques to tuple spaces in order to increase their
performance when handling a large number of tuples. Moreover, we have studied how structured
peer to peer approaches can be applied to better distribute tuples on large networks. Using some of
these result, we have developed a tuple space implementation for the Globus Toolkit that can be
used by Grid applications as a coordination service. The development of such a service has been
quite challenging due to the limitations imposed by XML serialization that have heavily influenced
its design. Nevertheless, we were able to complete its implementation and use it to implement two
different types of test applications: a completely parallelizable one and a plasma simulation that is
not completely parallelizable. Using this last application we have compared the performance of our
service against MPI. Finally, we have developed and tested a simple workflow in order to show the
versatility of our service.
10
Khan, Ahmed. "Evaluation and Implementation of Linux User-space Fast Path Technologies : Linux, User-space." Thesis, Mittuniversitetet, Institutionen för informationsteknologi och medier, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-19611.
Повний текст джерелаАнотація:
The enormous increase in device connectivity for data and telecom devices places significant challenges on the packet processing techniques used in embedded systems such as IP stacks. Therefore, the traditional packet processing software cannot handle the line rate packet flow even for the most cutting edge devices. A solution to this problem is to allow applications to directly receive packets without passing through the normal kernel stack and drivers i.e. interface directly with the hardware. Two such open source libraries for Linux are PF_RING and Netmap. In addition Freescale has a similar technology called USDPAA. In order to satisfy the first goal of this project, a detailed analysis and evaluation of PF_RING, Netmap and USDPAA has been conducted in order to determine how they compare in relation to a number of criteria such as functionality, support, performance, ease of use, software/ hardware dependencies and project stability etc. Secondly based on the earlier work, a design is proposed that can be used to build and port an application to run on Freescale DPAA based hardware (P4080) on top of USDPAA.
11
Lacroix, Frédéric 1973. "Design, analysis and implementation of free-space optical interconnects." Thesis, McGill University, 2001. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=38072.
Повний текст джерелаАнотація:
Optical interconnects represent an attractive alternative technology for the implementation of dense, high-speed interconnects, as they do not suffer from many of the problems plaguing electrical interconnects such as frequency-dependent crosstalk and attenuation.However, optics has still not been accepted commercially as an interconnect technology. There is concern regarding the cost and complexity of the optomechanics needed to achieve the very fine alignments necessary to guarantee that the light emitted from the source actually falls on the receiver. The demonstration of a simple-to-assemble, dense and robust optical interconnect would constitute an important proof of the practicality of this technology. The photonic backplane demonstrator system presented in this thesis addresses these issues through a novel approach; the system uses slow Gaussian beams (f/16) and a clustered design to maximize misalignment tolerances. This in turn relaxes the positioning and packaging requirements for the components, thus simplifying assembly.
This thesis pursues two sets of complementary goals; the first set is concerned with the demonstration of some desirable optomechanical characteristics for optical interconnects such as passive alignment, repeatability and stability while the second set of goals is concerned with a verification of hypotheses often used in the design and implementation of optical interconnects. Such hypotheses are often used in practice to design optical interconnects despite the fact that little data exists in the literature to warrant their use. It therefore makes good sense to spend some time verifying the accuracy of these models. This will provide a solid engineering foundation for the design of future systems.
12
Huang, Xiaoqiang. "Comparison, implementation and evaluation of morphological scale-space image trees." Thesis, University of East Anglia, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.426691.
Повний текст джерела
13
Berhanu, Samuel, and Kamal Neupane. "Digital Radio Implementation for NASA S-Band Space Network Transceiver." International Foundation for Telemetering, 2012. http://hdl.handle.net/10150/581843.
Повний текст джерелаАнотація:
The system diagrams for the digital radio compatible with NASA's S-Band Space Network operating from 2025.8 - 2117.9 MHz (forward link) to 2200 - 2300 MHz (return link) are presented. The digital radio implementation includes binary phase shift keying (BPSK), quadrature phase shift keying (QPSK) and staggered quadrature phase shift keying (SQPSK). We have derived the system requirements for these modulation schemes from the Space Network User Guide (SNUG) and thereafter, derived system diagrams for the communication links. The designed system diagrams for the transceiver were implemented using Simulink models and USRP2 platform.
14
Häfliger, Philipp D. "A spike based learning rule and its implementation in analog hardware /." [S.l.] : [s.n.], 2000. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=13581.
Повний текст джерела
15
Tolunay, Bengi. "Space Vector Pulse Width Modulationfor Three-Level Converters : a LabVIEW Implementation." Thesis, Uppsala universitet, Elektricitetslära, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-169019.
Повний текст джерелаАнотація:
This thesis explains the theory and implementation of the Space Vector Pulse WidthModulation (SVPWM) using the graphical programming environment LabVIEW as itsbasis. All renewable energy sources are in need of multilevel power electronics inform of multilevel inverters. The mind behind the pulses created by the inverters isthe SVPWM. This modulation type uses a space vector, referred to as the referencevector, to locate and create the desired sinusoidal-shaped waveform. Using LabVIEWas the software makes it easy to read real-time output from the integrated circuit ofthe hardware (FPGA). The SVPWM shows good utilization of the DC-link voltage,low current ripple and is relatively easy to implement in the hardware, making itsuitable for any high-voltage, high-power application.
16
Kronberg, Anders. "Salient Pole Motor Inverter Design : with Implementation of Space Vector Modulation." Thesis, Uppsala universitet, Elektricitetslära, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-192994.
Повний текст джерелаАнотація:
The researchers at the Department of Electricity at Uppsala University has recently entered the field of electric motor design, however no real knowledge of motor control of salient pole permanent magnet motors exists in the department. This master thesis is a continuation of a previous bachelor thesis that analyses the theory behind the control and simulating two different control methods. The two methods are here discarded for their high torque ripple. A third method is therefore implemented in this thesis to improve the performance. This thesis will present the design and construction of an inverter for driving of a 30kW permanent magnet motor intended for vehicle propulsion. The work is divided into two parts, the power electronics and the control system hardware and software. The results shows a working concept for a drive system, but further testing and improvements are needed to achieve maximum efficiency of the whole system.Ett drivsystem för högeffektiva elektriska fordonsmotorer har konstruerats och testats på en 30kW motor utvecklad på Uppsala universitet. Resultaten visar att systemet fungerar, men att det även finns behov av förbättringar. Med tanke på de senaste årens forskning och debatt om peak oil och en ökande mängd växthusgaser i atmosfären har det blivit tydligare att världens energikonvertering måste förändras för ett mer hållbart samhälle. Avdelningen för elektricitetslära på Uppsala universitet har det senaste decenniet fokuserat på utveckling av förnyelsebara energikällor, så som vind-, våg-, vatten- och marin strömkraft. Med samma verktyg och metoder som använts vid utvecklingen av högeffektiva generatorer har de nyligen gett sig in på området elektriska motorer för fordonsframdrift. En av elbilens nackdelar är dess räckvidd, för att kunna konkurrera med dagens bilar är det därför viktigt att optimera verkningsgraden i de olika delsystemen mellan laddkontakt och hjul. I detta arbete presenteras en metod i vilken de tre fasernas drivelektronik styrs som en enhet istället för att behandla den som tre oberoende enheter. Detta möjliggör en 15.4% högre drivspänning till motorn, vilket leder till lägre strömmar och förluster för samma uteffekt. Arbetet omfattar konstruktion av kraftelektronik, styrelektronik och programmering av styrelektroniken, samt test och verifiering av hela systemet.
17
Jing, Ming-Haw. "The implementation of a fault-tolerant computer system for space instrumentation." Thesis, University of Sheffield, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.285034.
Повний текст джерела
18
Van, der Horst Johannes Gerhardus. "Radiation tolerant implementation of a soft-core processor for space applications." Thesis, Stellenbosch : University of Stellenbosch, 2007. http://hdl.handle.net/10019.1/1857.
Повний текст джерелаАнотація:
Thesis (MScEng (Electrical and Electronic Engineering))--University of Stellenbosch, 2007.The availability of high density FPGAs has made the use of soft-core processors an attractive proposition for the low volume space market. Soft-core processors combine the power of programmable logic with the ease of use of a conventional processor to provide a highly customisable solution. However, the SRAM FPGAs used as implementation platform are especially susceptable to radiation induced single event upsets, due to the sensitivity of their configuration memory. To safely use these processors in a space environment requires the modification of the processor to safely mitigate these effects. This thesis presents the process followed to develop and test a fault tolerant implementation of an 8-bit PicoBlaze soft-core processor on a Xilinx Spartan-3 SRAM FPGA. A thorough investigation was made into the available methods that can be used to mitigate single event upsets, in order to identify the most suitable ones. Guidelines for the application of SEU mitigation techniques to SRAM FPGAs were proposed. A single event upset simulator was designed and constructed to compare the different techniques. It mimics SEUs by injecting errors into the configuration memory of an FPGA. The results of error injection were used to develop a PicoBlaze implementation with limited overhead, while it still offers a high degree of error mitigation. Three different designs were tested by proton irradiation to verify the protection afforded by the mitigation techniques. It was found that protected designs were more robust. The cross-section of the FPGA was also determined, which can be used with the SEU simulator to predict the dynamic cross-section of designs. The work contained in this thesis demonstrates the use of open-source intellectual property with commercial-off-the-shelf components to develop a robust component for use in the miniature spacecraft market.
19
DeBoy, Christopher C., Paul D. Schwartz, and Richard K. Huebschman. "Midcourse Space Experiment Spacecraft and Ground Segment Telemetry Design and Implementation." International Foundation for Telemetering, 1996. http://hdl.handle.net/10150/608390.
Повний текст джерелаАнотація:
International Telemetering Conference Proceedings / October 28-31, 1996 / Town and Country Hotel and Convention Center, San Diego, CaliforniaThis paper reviews the performance requirements that provided the baseline for development of the onboard data system, RF transmission system, and ground segment receiving system of the Midcourse Space Experiment (MSX) spacecraft. The onboard Command and Data Handling (C&DH) System was designed to support the high data outputs of the three imaging sensor systems onboard the spacecraft and the requirement for large volumes of data storage. Because of the high data rates, it was necessary to construct a dedicated X-band ground receiver system at The Johns Hopkins University Applied Physics Laboratory (APL) and implement a tape recorder system for recording and downlinking sensor and spacecraft data. The system uses two onboard tape recorders to provide redundancy and backup capabilities. The storage capability of each tape recorder is 54 gigabits. The MSX C&DH System can record data at 25 Mbps or 5 Mbps. To meet the redundancy requirements of the high-priority experiments, the data can also be recorded in parallel on both tape recorders. To provide longer onboard recording, the data can also be recorded serially on the two recorders. The reproduce (playback) mode is at 25 Mbps. A unique requirement of the C&DH System is to multiplex and commutate the different output rates of the sensors and housekeeping signals into a common data stream for recording. The system also supports 1-Mbps real-time sensor data and 16-kbps real-time housekeeping data transmission to the dedicated ground site and through the U.S. Air Force Satellite Control Network ground stations. The primary ground receiving site for the telemetry is the MSX Tracking System (MTS) at APL. A dedicated 10-m X-band antenna is used to track the satellite during overhead passes and acquire the 25-Mbps telemetry downlinks, along with the 1-Mbps and 16-kbps real-time transmissions. This paper discusses some of the key technology trade-offs that were made in the design of the system to meet requirements for reliability, performance, and development schedule. It also presents some of the lessons learned during development and the impact these lessons will have on development of future systems.
20
Tang, Yipeng. "DSP implementation of trellis coded modulation and distributed space time coding." Morgantown, W. Va. : [West Virginia University Libraries], 2001. http://etd.wvu.edu/templates/showETD.cfm?recnum=1796.
Повний текст джерелаАнотація:
Thesis (M.S.)--West Virginia University, 2001.Title from document title page. Document formatted into pages; contains v, 118, [64] p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 114-118).
21
Cirillo, Giovanni. "Space Surveillance and Tracking Tool: Implementation and Test of New Methods." Thesis, KTH, Rymdteknik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-262030.
Повний текст джерелаАнотація:
In March 2019 the number of artificial objects bigger than 1 mm in orbit around the Earth is estimated to be more than 170 millions. Only a small fraction of them (0.03%) is catalogued. An impact of an operational satellite with one of these debris can damage the satellite and undermine its mission. So it is important to catalogue as many objects as possible in order to reduce the risk of a collisions. This is done by using the software tool Space Object Observations and Kalman Filtering (SPOOK), developed in Airbus Defence and Space in Friedrichshafen. The goal of this Master Thesis was to create newfunctionalities to this tool and improve the existing ones. In particular three main goals have been accomplished: • a new model for the lighting ratio has been built to take into account the occultation of the Sun due to a covering body (for example the Earth or the Moon) and itsinfluence on the solar radiation pressure, necessary to have a good model for orbit propagation; • a tracklet building algorithm has been built to distinguish different tracklets (consecutive observations of the same object along its orbit) as a starting point for the association of different measurements belonging to the same object at distant epochs, necessary to update a catalogue of space objects; • a model to take into account the process noise has been improved giving some suggestion on how to tune the different parameters for different kinds of orbit.I mars 2019 uppgick antalet konstgjorda föremål större än 1 mm i omloppsbana runt jorden till över 170 miljoner. Av dessa är endast en mycket liten andel (0.03%) katalogiserade. En kollision mellan en operativ satellit och ett annat föremål i bana kan helt eller delvis förstöra satelliten. För att reducera risken för kollisioner är det därför viktigt att katalogisera så många föremål som möjligt. Detta görs genom att använda programvaran "Space Object Observations and Kalman Filtering" (SPOOK), som utvecklats av företaget Airbus Defence and Space i Friedrichshafen, Tyskland. Målet med detta examensarbete var att skapa nya funktioner i programvara samt att förbättra de befintliga funktionerna. Tre huvudmål har uppnåtts: • En ny modell för ljusförhållandet har skapats för att ta hänsyn till ocklutationen av solen på grund av en täckande kropp (till exempel jorden eller månen) och dess påverkan på solstrålningstrycket på rymdfarkosten, vilket är nödvändigt för att ha en bra modell för hur omloppsbanan fortplantas • En algoritm för s.k. tracklets, flera observationer av samma föremål längs dess omlopp, har skapats i syfte att skilja mellan olika tracklets som utgångspunkt för bestämma vilka mätningar som tillhör samma föremål vid avlägsna epoker. Detta är nödvändigt för att korrekt kunna uppdatera katalogen över rymdföremål. • Modellen för att ta hänsyn till processbruset har förbättrats och förslag ges om hur man ställer in olika parametrar för olika slags omloppsbanor.
22
ROSSI, VALERIO. "Advanced multibody dynamics formulations for space applications: from theory to implementation." Doctoral thesis, Università degli Studi di Roma "Tor Vergata", 2014. http://hdl.handle.net/2108/202968.
Повний текст джерелаАнотація:
Recently, the interest of the space agencies in missions involving the soft-landing of a
spacecraft on the surface of moons, planets, asteroids and comets is growing. Modern
CAE tool can extensively improve the design of such complex systems. Nevertheless few
multibody codes are tailored for space applications. DCAP is a multibody software widely
used by the European Space Agency over the last 30 years and specifically produced for
the dynamic analysis of space mechanisms. In order to perform a dynamic analysis of a
soft-landing of a spacecraft, particular features need to be available.
The focus of this thesis is the development, from theory to implementation, of innovative
features for the multibody DCAP software in order to extend its simulation capabilities.
DCAP is established on a recursive multibody formulation based on Maggi-Kane’s
equations. Quaternions have been implemented in DCAP code in order to avoid the gimbal
lock singularity generated from the use of the Euler angles. A modern numerical integrator
with variable step size and variable order has been studied and added to the DCAP
solver options. Three different contact types have been formulated and implemented and
an extensive review of the most widespread dry friction force models has been accomplished.
A multibody simulation of a soft-landing of a spacecraft on the surface of an
asteroid is reported to highlight the benefits of the developments implemented. A second
numerical simulation has been investigated to illustrate a modelling approach for studying
multiple closed loop topology systems.
23
Perez, Richard. "The Canadian C-Spine Rule and CT-Head Rule Implementation Studies: A Psychological Process Evaluation." Thesis, Université d'Ottawa / University of Ottawa, 2011. http://hdl.handle.net/10393/19814.
Повний текст джерелаАнотація:
The Canadian C-Spine (CS) and CT-Head (CT) Rules are tools aimed at improving the accuracy and efficiency of radiography use in emergency departments. This study evaluated whether the Theory of Planned Behaviour (TPB) could explain the inconsistent results from implementation studies of these two rules at 12 Canadian hospitals, where the same intervention resulted in a significant reduction in CS radiography but not CT radiography. It was demonstrated that the TPB model’s proposed relationships between constructs and behaviour could explain the ordering of CS but not CT radiography. However, after examining longitudinal changes of the TPB constructs, it was clear that these changes could not explain the changes in CS radiography ordering. Overall, TPB is unlikely to suggest important ways by which to improve radiography use, for CT because its constructs are not related to radiography ordering, and for CS because of high baseline levels of intention to clinically clear.
24
Simons, Kevin J. "The Work Process of Research Librarians: Implementation of the Abstraction-Decomposition Space." Connect to this document online, 2005. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=miami1113847496.
Повний текст джерелаАнотація:
Thesis (Ph.D.)--Miami University, Dept. of Psychology, 2005.Title from second page of PDF document. Document formatted into pages; contains [2], vi, 72, [22] p. : ill. Includes bibliographical references (p. 35-37).
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Ozdemir, Basak Gonca. "Power Stage Design And Implementation Of A Deploymentmechanism Driver For Space Applications." Master's thesis, METU, 2012. http://etd.lib.metu.edu.tr/upload/12614058/index.pdf.
Повний текст джерелаАнотація:
With the developments in space technology, the capabilities of spacecrafts have been
increased considerably which in turn have entailed the development of more efficient
spacecrafts in terms of cost, mass, size and power. One way to achieve such a development
is the replacement of body mounted appendages with the deployable ones, which greatly
reduces the size, mass and cost of the spacecraft especially when large appendages are
considered. In order to obtain these deployable structures, deployment mechanisms and
deployment mechanism drivers are used. A deployment mechanism is a combination of
electrical and/or mechanical structures which hold the appendages in the stowed position
before launch and deploys them after the launch with the power and commands supplied by
the deployment mechanism driver. This necessary power of the deployment mechanism
driver is produced by the Power Stage of the deployment mechanism driver and the
necessary commands required by the deployment mechanism are supplied by the Control
Stage of the deployment mechanism driver. In this thesis, the power stage of a deployment
mechanism driver will be designed and implemented taking into account of the
requirements for Low Earth Orbit Satellites such as temperature tolerance, reliability and
radiation limits. In order to acquire a cost, mass and size efficient Power Stage, different
deployment mechanism topologies will be studied and the most convenient one among
these topologies will be chosen as the deployment mechanism driver load and the design
will be performed accordingly.
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Liu, Yongsheng. "Design, implementation and characterization of free-space optical interconnects for optical backplanes." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape11/PQDD_0017/NQ44498.pdf.
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Liu, Yongsheng 1963. "Design, implementation and characterization of free-space optical interconnects for optical backplanes." Thesis, McGill University, 1997. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=34752.
Повний текст джерелаАнотація:
Free-space optical interconnects (FSOIs) represent a potential solution for solving the bottleneck associated with the increasing demands for high bandwidth interconnections in modern communication services and advanced computing systems. Such interconnects utilize two-dimensional smart pixel arrays to take advantage of the additional degree of freedom gained in FSOIs. As a result, thousands of parallel optical channels may be available. This thesis studies the design issues of board-to-board free-space optical interconnections. The impacts of device technology, the data-link topology of multiple-board interconnections, and the imaging mapping between stages are explored. Four types of free-space optical interconnects have been examined in terms of system complexity, scalablity, and alignability. In particular, the alignment tolerance of a symmetric optical interconnect is analytically studied. Comparison of alignment tolerances is carried out between a system with telecentric configuration and a system with maximum lens-to-waist configuration. It has been shown that interconnection between integrated microlenses/transmitters and microlenses/receivers is generally more alignment toleranced than that of non-optical integrated transmitters and receivers.Key issues are identified and explored in the design, implementation and characterization of three types of optical systems, namely macrolens based optical interconnect, microlens based optical interconnect and hybrid-lens based optical interconnect. The microchannel optical interconnect employing a window-clustering scheme is demonstrated as well. The uniformity issue of a spot array generation using diffractive fanout gratings is experimentally studied. Imaging mapping between interconnection stages is developed using a standard matrix representation. For a complex multistage modulator-based free-space optical interconnet, the component requirements, alignment and assembly procedures, characterizing techniques, and system performance are presented. It is believed that modular subsystems with passive in-situ alignment techniques have potential for providing the required alignment solution of implementing free-space board-to-board interconnects.
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Tubbs, Casey. "IRIG-106 PCM IMPLEMENTATION UTILIZING CONSULTATIVE COMMITTEE FOR SPACE DATA SYSTEMS (CCSDS)." International Foundation for Telemetering, 1990. http://hdl.handle.net/10150/613777.
Повний текст джерелаАнотація:
International Telemetering Conference Proceedings / October 29-November 02, 1990 / Riviera Hotel and Convention Center, Las Vegas, NevadaAsynchronous data sources such as those associated with Space Based Radar create a unique problem for Time Division Multiplexed (TDM) Pulse Code Modulation (PCM) frame formats. The problem consists of data arrival based on external occurrences such as target tracking, and not due to sampling polls from internal sequencers. Reserved time slots for asynchronous data must be provided within the synchronous TDM telemetry stream. This increases the required bandwidth to transfer collected data to ground sites proportional to the worst case arrival rate of asynchronous data and the maximum latency allowed for the application. Asynchronous data is readily handled by the Consultative Committee for Space Data Systems (CCSDS) recommended formats without the need to increase the bandwidth disproportionately. The recommendation maintains the ability to provide synchronous telemetry data collection and transmission provided by the TDM PCM frame formats. This paper provides an implementation of CCSDS recommendations and addresses the methodology of merging asynchronous and synchronous data sources without the prerequisite increase in bandwidth associated with purely synchronous TDM approaches. Additional implementation details are provided for the implementation of a Telemetry Operation Procedure (TOP) to downlink error free telemetry frames. The TOP is not currently supported within the CCSDS recommendation. The implementation is provided through the Micro Packaged Data Acquisition and Control Systems developed by SCI Technology in Huntsville, Alabama.
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Juanola-Parramon, R. "A far-infrared spectro-spatial space interferometer : instrument simulator and testbed implementation." Thesis, University College London (University of London), 2014. http://discovery.ucl.ac.uk/1427371/.
Повний текст джерелаАнотація:
FIRI (Far Infrared Interferometer) is a concept for a spatial and spectral space interferometer with an operating wavelength range 25-300 μm and sub-arcsecond angular resolution, and is based on the combination of two well-known techniques, Stellar Interferometry and Fourier Transform Spectroscopy, to achieve high spectral and spatial resolution in the Far Infrared (Chapter 2). The resulting technique is called Double Fourier Spatio-Spectral Interferometry (Mariotti and Ridgway 1988). With increased spatial and spectral resolution a number of interesting science cases such as the formation and evolution of AGN and the characterization of gas, ice and dust in disks undergoing planetary formation, among others, can be investigated. In this thesis I present two approaches to study the feasibility of a FIRI system a) An experimental approach via the Cardiff University-UCL FIRI Testbed (Chapter 3), a laboratory prototype spectral-spatial interferometer to demonstrate the feasibility of the Double-Fourier technique at the Far-infrared regime, including the Wide-Filed Imaging Interferometry Testbed at the Optical and Near-infrared regime. b) The Far-Infrared Interferometer Instrument Simulator (FIInS) to assess the performance of a space-based system (Chapter 4). The main goal of this software is to simulate both the input and the output of such a system. With FIInS, once a set of modeled scientific data is available, one can compare an input sky map with the synthesized one after data reduction and processing algorithms have been applied. To validate FIInS data from the Cardiff University-UCL FIRI testbed has been used (Chapter 5). FIInS is intended to be a tool for the astronomical community to explore the limits of a space interferometer. For this reason it is also applied to simulated scientific data (Chapter 6), more specifically to simulated circumstellar disks to test the simulator in a more realistic scenario.
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Bruno, Lucien V. IV. "Contested Road Space: Public Narratives and Bus Rapid Transit in Indore, India." ScholarWorks@UNO, 2014. http://scholarworks.uno.edu/td/1850.
Повний текст джерелаАнотація:
Bus Rapid Transit (BRT) has a demonstrated capacity to improve safety, mobility and accessibility for multiple types of road users. In India, where road safety is an ongoing problem, the national government has supported cities’ efforts to implement BRT as a cost-effective tool to improve urban travel. The case of Indore’s iBus attests to the cultural and institutional barriers that Indian cities may face in gaining public support for BRT. After a contentious implementation process, the High Court ruled to open the dedicated bus lane to private automobiles, resulting in drops in ridership and increases in accidents and travel delay. This study examines the competing, public narratives that framed the issues during and after project construction. Contested notions of the public interest, the cause of traffic problems, and community participation informed the basis for the arguments that culminated in the court ruling.
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Perez, Casanova Gaspar M. "Implementation of a fault tolerant control unit within an FPGA for space applications." Thesis, Monterey, Calif. : Naval Postgraduate School, 2006. http://bosun.nps.edu/uhtbin/hyperion.exe/06Dec%5FPerez%5FCasanova.pdf.
Повний текст джерелаАнотація:
Thesis (M.S. in Electrical Engineering)--Naval Postgraduate School, December 2006.Thesis Advisor(s): Herschel H. Loomis, Alan A. Ross. "December 2006." Includes bibliographical references (p. 77-83). Also available in print.
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Andersen, Dennis. "Screen-Space Subsurface Scattering, A Real-time Implementation Using Direct3D 11.1 Rendering API." Thesis, Blekinge Tekniska Högskola, Institutionen för kreativa teknologier, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-661.
Повний текст джерелаАнотація:
Context Subsurface scattering - the effect of light scattering within a material. Lots of materials on earth possess translucent properties. It is therefore an important factor to consider when trying to render realistic images. Historically the effect has been used for offline rendering with ray tracers, but is now considered a real-time rendering technique and is done based on approximations off previous models. Early real-time methods approximates the effect in object texture space which does not scale well with real-time applications such as games. A relatively new approach makes it possible to apply the effect as a post processing effect using GPGPU capabilities, making this approach compatible with most modern rendering pipelines. Objectives The aim of this thesis is to explore the possibilities of a dynamic real-time solution to subsurface scattering with a modern rendering API to utilize GPGPU programming and modern data management, combined with previous techniques Methods The proposed subsurface scattering technique is implemented in a delimited real-time graphics engine using a modern rendering API to evaluate the impact on performance by conducting several experiments with specific properties. Results The result obtained hints that by using a flexible solution to represent materials, execution time lands at an acceptable rate and could be used in real-time. These results shows that the execution time grows nearly linearly with consideration to the number of layers and the strength of the effect. Because the technique is performed in screen space, the performance scales with subsurface scattering screen coverage and screen resolution. Conclusions The technique could be used in real-time and could trivially be integrated to most existing rendering pipelines. Further research and testing should be done in order to determine how the effect scales in a complex 3D-game environment.
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PACHECO, LABRADOR JORGE. "Design and implementation of 1GbpsLaser Ethernet Transceiver (LET) for Free-Space Optical communications." Thesis, KTH, Rymd- och plasmafysik, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-152465.
Повний текст джерелаАнотація:
Free Space Optical (FSO) communications are an emerging technology. Multiple resources around the world are being dedicated to the study and implementation of associated technologies. The possibility of high data rates, lower masses and more power efficient antennas are the expected advantages of these systems. However FSO channels are highly vulnerable. Atmospheric perturbations as well as pointing misalignments compromise the integrity of the transmitted data. Besides, current data protection architectures for FSO communication systems are not powerful enough to protect the data due to the nature of the perturbations. Therefore, Deutsches Zentrum für Luft- und Raumfahrt (DLR) is working on the implementation of a communication protocol (Laser Ethernet Transceiver protocol, LET) capable of transmitting high bit rates reliably. LET has to overcome the multiple errors induced by the disturbances in the channel (fades in the signal induced by the atmosphere and miss-pointing) and data stream misalignments during transmission. In addition, LET has to provide a framework for transmitting 1GbE (Gigabit Ethernet) payloads. Thus the focus of this MSc Thesis is on the definition and implementation of the abovementioned algorithms and hardware structures. These hardware structures are developed for their integration on Field Programmable Gate Arrays (FPGA) in VHDL language. At the end of this MSc Thesis, a significant improvement of 3.5 dB in the optical gain has been achieved with a Bit-Level Forward Error Correction (BLFEC) implementation. Some of the hardware structures have also been implemented and tested for the next steps. An analysis of the synchronization problems that will affect the system has been done and a technical solution has been provided. Additionally, an improvement of the channel throughput has been achieved in order to comply with the 1GbE Standard.
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Maples, Bruce W., and Keith A. Fix. "An IF Sampling Digital Receiver Implementation for Space-based Command and Telemetry Applications." International Foundation for Telemetering, 2002. http://hdl.handle.net/10150/607493.
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International Telemetering Conference Proceedings / October 21, 2002 / Town & Country Hotel and Conference Center, San Diego, CaliforniaThis paper describes an approach to the implementation of an IF sampling digital receiver for low data rate command and telemetry applications in the NASA Goddard Spaceflight Tracking and Data Network (STDN) and Air Force Space-Ground Link System (SGLS). The digital design is targeted for an FPGA-based implementation and was written entirely in VHDL. Several size and clock reduction techniques are described which were utilized due to limited gate-array resources and power. The system-level design architecture is described followed by a discussion of algorithms and performance of critical stages in the receiver chain. Bit error performance of the prototype receiver is also presented. Finally, although this design is specifically targeted for a narrowband command and telemetry application, the methodology forms the basis of a configurable receiver for higher data rate applications.
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Sobhanmanesh, Fariborz School of Electrical Engineering And Telecommunications UNSW. "Hardware implementation of V-BLAST MIMO." Awarded by:University of New South Wales. School of Electrical Engineering And Telecommunications, 2006. http://handle.unsw.edu.au/1959.4/24198.
Повний текст джерелаАнотація:
The exploitation of the theoretically enormous capacity achieved by the multiple transmit and receive antennas systems (MIMO) in a rich scattering communication channel has been the subject of vast body of research on the field of MIMO. In particular, the Vertically-layered Bell Laboratories Layered Space-Time (V-BLAST) is a well known MIMO architecture which has demonstrated the enormous capacity of 20-40 bit/s/Hz in an indoor propagation environment with realistic SNR and error rates. However, due to the intensive computation involved, it would be difficult to implement this architecture for high data rate communication systems. Some works have been done to improve the receiver complexity and performance by coding techniques, by different detection architectures. In this thesis, we have focused on QR-based decoders for V-BLAST MIMO. For a suitable V-BLAST detection implementation, we need to carefully consider the problem from algorithmic, arithmetic and architectural aspects. At the algorithmic level, the numerical stability and robustness should be considered. At the arithmetic level, signal quantization is important, and, at the architectural level, parallelism and pipelining require attention. We have performed the above mentioned optimization on the 1-pass QR factorization with back substitution SIC (Symbol Interference Cancellation) decoder in chapter 3. At first optimizations are made on the proposed algorithm and architecture using MATLAB simulations. Then a new architecture for the QR-factorizer as the core processor of the V-BLAST decoder is developed in chapter 4. This architecture uses only two low complexity CORDIC (Coordinate rotation digital computer) processors. The parameterized feature of the controller and address generator blocks of this architecture has provided a scalable architecture for the implementation of QR factorization for square matrix of any dimension. The reduced hardware complexity of the processors and its simple parameterized controller are two outstanding features of the architecture, resulting in a more suitable alternative architecture for QR factorization than traditional triangular systolic arrays. In the next phase of the research, new hardware architectures of the back substitution SIC decoder was developed for a 4 X 4 MIMO system with 16-QAM constellation scheme in chapter 5. The division operation for back substitution needs a complex hardware, and results in the numerical instability. In the proposed hardware the elimination of division and modification of multiplier has reduced the hardware complexity and led to numerical stability. In addition the pre decoding block was designed and optimized in terms of number of the pipeline registers and CORDIC rotator processors. The developed hardware is capable of processing 20 vectors data burst and results in a throughput of 149 Mb/s. The FPGA (Field Programmable Gate Array) and ASIC (Application specific Integrated Circuit) implementations of the proposed optimized architecture are presented in Chapter 5. We found that the equivalent gates and the core area in our design is less than 30% of other designs and the maximum clock frequency and the throughput is higher (175 %) than other works. Finally the improvements of the BER performance using the branching method and parallel architectures are presented in chapter 6. In this supplementary part to back substitution OSIC decoder, the final symbol vector is selected from 2 or 8 potential candidates based on the minimum Euclidean norm, which improves the BER between 3 to 7 db and gives a very close match to the original V-BLAST performance.
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Trochimczyk, Maja. "Space and spatialization in contemporary music : history and analysis, ideas and implementations." Thesis, McGill University, 1994. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=116333.
Повний текст джерелаАнотація:
Note: Pages have been removed from this digital copy due to copyright restrictions. A print copy is available in the McGill Library.This dissertation presents the history of space in the musical thought of the 2Othcentury (from Kurth to Clifton, from Varèse to Xenakis) and outlines the development of spatialization in the theory and practice of contenlporary music (after 1950). The text emphasizes perceptual and temporal aspects of musical spatiality, thus reflecting the close connection of space and time in human experience. A new definition of spatialization draws from Ingarden’s notion of the musical work; a new typology of spatial designs embraces music for different acoustic environments, movements of performers and audiences, various positions of musicians in space, etc. The study of spatialization includes a survey of the writings of many composers (e.g. Ives, Boulez, Stockhausen, Cage) and an examination of their compositions. The final part of the dissertation presents three approaches to spatialization: Brant’ s simultaneity of sound layers, Xenakis’s movement of sound, and Schafer’s music of ritual and soundscape.
Cette thèse présente l’histoire de l’espace dans la pensée musicale du vingtième siècle (de Kurth à Clifton, de Varèse à Xenakis) et retrace le développement de la spatialisation dans la théorie et la pratique de la musique contemporaine (après 1950). Le texte souligne les aspects perceptuels et temporels de la spatialisation musicale, reflétant ainsi le lien étroit entre temps et espace t!ans l’expérience humaine. Une nouvelle définition de la spatialisation tire son origine de la notion de l’oeuvre musicale d’Ingarden; une nouvelle typologie des plans spatiaux prend en considération des musiques pour différents environnements acoustiques, diverses positions des musiciens dans l’espace de même que le mouvement de ceux-ci et des auditeurs, etc. L’étude de la spatialisation inclut un survol des écrits de plusieurs compositeurs (Ives, Stockhausen, Boulez et Cage, par exemple) de même qu’un examen de leurs oeuvres. La dernière partie de la thèse présente trois approches compositionnelles de la spatialisation: la simultanéité de strates sonores ,:hez Brant, le mouvement du son chez Xenakis et la musique du rituel et l’écologie sonore chez Schafer.
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Gummalla, Srikanth. "Design and Implementation of an Optical Tag Reader." University of Cincinnati / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1229447375.
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García, de Herreros Miciano María. "Feasibility study of the implementation of a space sunshade near the first Lagrangian point." Thesis, KTH, Rymdteknik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-280140.
Повний текст джерелаАнотація:
The lack of strong measures to avoid the possible fatal consequences of global warming is pushing researchers to look for other alternatives such as geoengineering.Within geoengineering, this study focuses on the space based solar radiation management methods. More precisely, the project evaluates the feasibilityof implementing a space sun shade near the first Lagrangian point in the Sun-Earth system within a thirty year period time from now. The study isstructured in three main blocks: spacecraft configuration, trajectory definition and launch. An analysis looking at the minimum cost system was carried out,starting with the definition of the mass and size of spacecraft. Furthermore, an optimization of the trajectory was developed in order to minimize the traveltime to the vicinity of the Lagrangian point. The shades will be formed by swarms of 10 000m2 solar sails that will cover an area of 6:3 x 1012 m2 witha total mass of around 5:7 x 1010 kg. The sails will be injected into a LEO and will start a trajectory to the vicinity of the first Lagrangian point that willtake around 2.3 years. The total cost of the project is approximated to be 10 trillion dollars. The mission appears to be feasible from a technological pointof view, with some development needed in the attitude control subsystem. The main challenge will be the launch of all the spacecraft. A space mission of thisdimensions has never been attempted before so it will require a big advance from the launch vehicle industry.Bristen på åtgärder för att undvika de konsekvenser som den globala uppvärmingen leder till, har drivit forskare att leta efter alternativa lösningar, varav geoengineering är en av dem. Denna studie fokuserar på rymdbaserade strålhanteringsmetoder, mer specifikt på hur huruvida implementationer av solparasoller nära Lagrangepunkten L1 i sol-jord-systemet är möjlig eller ej. Studien är strukturerad i tre huvudsakliga block: rymdskeppskonfiguration, banadefinition och uppskjutning. Med målet att minimera kostnaderna, definierades rymdskeppets utforming, massa och storlek. Vidare så, optimerades vägen till närheten av L1 med avseende på att minimera tiden. Solparasollerna kommer vara placerade i svärmar med en area på 10 000m2 vardera, totalt kommer solparasollerna att täcka en yta av 6:3 x 1012 m2 med en total massa på 5:7 x 1010 kg. Solparasollerna kommer skjutas upp till LEO och därefter starta sin resa till närheten av L1, vilket kommer ta cirka 2.3 år. Totala kostanden för projektet uppskattas till 10 billioner dollar. Efter genomförd studie visades projektet vara genomförbart sett från en teknisk synvinkel, men vidare studier behövs göras för att utveckla och fastställa styrsystemet. Huvudutmaningen kommer att vara uppskjutningen av rymdskeppen, då det kräver stora framsteg och utveckling inom rymdindustrin.
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Ramsey, John Karl. "Vector-space implementation of Hamilton's law of varying action for linear and nonlinear systems /." The Ohio State University, 2000. http://rave.ohiolink.edu/etdc/view?acc_num=osu1488196234909189.
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Rödiger, Jasper. "Time-Frequency Quantum Key Distribution: Numerical Assessment and Implementation over a Free-Space Link." Doctoral thesis, Humboldt-Universität zu Berlin, 2020. http://dx.doi.org/10.18452/21046.
Повний текст джерелаАнотація:
Die Quantenschlüsselverteilung (QKD), die erste anwendbare Quantentechnologie, verspricht informationstheoretisch sichere Kommunikation. In der vorliegenden Arbeit wurde das Zeit-Frequenz (TF)-QKD-Protokoll untersucht, das Zeit und Frequenz, nämlich Puls-Positionsmodulation (PPM) im Zeitbereich und Frequenzumtastung (FSK) im Frequenzbereich als die beiden komplementären Basen verwendet. Seine Sicherheit beruht den Quanteneigenschaften von Licht und auf der Zeit-Frequenz-Unschärferelation.
TF-QKD kann mit größtenteils Standard-Telekommunikationstechnologie im 1550-nm-Band implementiert werden. Die PPM-Basis kann mit Modulatoren und die FSK-Basis mit Hilfe der Wellenlängenmultiplex-Technologie realisiert werden. Das TF-QKD-Protokoll ist in der Lage, ein beliebig großes Alphabet bereitzustellen, was mehr als 1 bit/Photon ermöglicht. Darüber hinaus ist es robust gegenüber athmosphärischen Störungen und somit für die Übertragung über den Freiraumkanal geeignet.
In der vorliegenden Arbeit wird das TF-QKD-Protokoll theoretisch bewertet, mit Standardkomponenten für 1 bit/Photon implementiert und die Freiraumübertragung mit optischem Tracking über eine 388 m Teststrecke wird bei Tageslicht demonstriert. Unter Verwendung der vorhandenen Komponenten konnte eine sichere Schlüsselrate von 364 kbit/s back-to-back und 9 kbit/s über den Freiraumkanal demonstriert werden.Quantum key distribution (QKD), the first applicable quantum technology, promises information theoretically secure communication. In the presented work the time-frequency (TF)-QKD protocol was examined, which uses time and frequency, namely pulse position modulation (PPM) in the time domain and frequency shift keying (FSK) in the frequency domain as the two complementary bases. Its security relies on the quantum properties of light and the time-frequency uncertainty relation. TF-QKD can be implemented mostly with standard telecom-technology in the 1550 nm band. The PPM basis can be implemented with modulators and the FSK basis with help of wavelength-division multiplexing technology. The TF-QKD protocol is capable of providing an arbitrarily large alphabet enabling more than 1 bit/photon. Moreover, it is robust in the atmosphere making it suitable for transmission over the free-space channel. In the present work the TF-QKD protocol is assessed theoretically, implemented with off-the-shelf components for 1 bit/photon and free-space transmission with optical tracking over a 388 m testbed is demonstrated in daylight. Using components at hand, secret key rates of 364 kbit/s back-to-back and 9 kbit/s over the free-space channel could be demonstrated.
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Hanebaum, Oliver [Verfasser]. "Implementation of FTLM for full Hilbert space investigation of anisotropic quantum spin systems / Oliver Hanebaum." Bielefeld : Universitätsbibliothek Bielefeld, 2018. http://d-nb.info/1169314848/34.
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McLachlan, Justiné. "Grade R teachers' understanding and implementation of the mathematical content knowledge of space and shape." Diss., University of Pretoria, 2018. http://hdl.handle.net/2263/65443.
Повний текст джерелаАнотація:
Globally, the importance of teaching mathematics to young children has rapidly increased. The concepts of space and shape are one of the mathematical content areas of mathematics that young children should explore, and Grade R teachers ought to understand and implement. Numerous theorists, researchers and authors have provided valuable insights and research on why Grade R teachers should be effectively teaching the mathematical content of knowledge of space and shape in their classrooms. In South Africa, several influences and contributing factors make it a challenge for Grade R teachers to implement the mathematical content knowledge of space and shape. This study sought to gain an insight in how Grade R teachers understand and implement the mathematical content knowledge of space and shape. The conceptual framework was developed from existing theories and research literature. A constructivist approach was followed. The framework comprised six levels to explain how Grade R teachers’ mathematical and pedagogical knowledge develops. The framework assisted in formulating questions and methods for the data collection process. The collected data was organised, transcribed and analysed. The study employed a qualitative case study design to generate data from five Grade R teachers’ experiences, views, ideas, opinions and perceptions on teaching the mathematical concepts of space and shape. Data were collected from the five teachers through participant observations, semi-structured interviews, documents and keeping a journal. The data analyses and findings support the themes and subthemes to answer the research questions. The findings from the research revealed that teachers should implement various innovative teaching approaches to facilitate active participation, so that the children could make their own meaning and understanding of the mathematical content of space and shape. Age-appropriate content and materials that scaffolds on children’s prior knowledge were found to be important strategies for effective teaching and learning. Teachers and their schools have a responsibility to establish positive learning environments as well as positive learning experiences for the children. The teachers in the study raised their concerns about the Curriculum and Assessment Policy Statements as they felt that they lacked creativity and guidance. Various factors with a negative impact on teaching and learning were identified and recommendations were made for improvement. The study concludes that Grade R teachers would benefit from gaining an in-depth understanding of the effective implementation of the mathematical content knowledge of space and shape.Dissertation (MEd)--University of Pretoria, 2018.
Early Childhood Education
MEd
Unrestricted
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Heaton, Tyler DeVoe. "Cloud Based IP Data Management Theory and Implementation for a Secure and Trusted Design Space." The Ohio State University, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=osu155498721009978.
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Han, Biao. "Predictive coding : its spike-time based neuronal implementation and its relationship with perception and oscillations." Thesis, Toulouse 3, 2016. http://www.theses.fr/2016TOU30029/document.
Повний текст джерелаАнотація:
Dans cette thèse, nous avons étudié le codage prédictif and sa relation avec la perception et les oscillations. Nous avons, dans l'introduction, fait une revue des connaissances sur les neurones et le néocortex et un état de l'art du codage prédictif. Dans les chapitres principaux, nous avons tout d'abord, proposé l'idée, au travers d'une étude théorique, que la temporalité de la décharge crée une inhibition sélective dans les réseaux excitateurs non-sélectifs rétroactifs. Ensuite, nous avons montré les effets perceptuels du codage prédictif: la perception de la forme améliore la perception du contraste. Enfin, nous avons montré que le codage prédictif peut utiliser des oscillations dans différentes bandes de fréquences pour transmettre les informations en avant et en rétroaction. Cette thèse a fourni un mécanisme neuronal viable et innovant pour le codage prédictif soutenu par des données empiriques démontrant des prédictions rétroactives excitatrices et une relation forte entre codage prédictif et oscillationsIn this thesis, we investigated predictive coding and its relationship with perception and oscillations. We first reviewed my current understanding about facts of neuron and neocortex and state-of-the-arts of predictive coding in the introduction. In the main chapters, firstly, we proposed the idea that correlated spike times create selective inhibition in a nonselective excitatory feedback network in a theoretical study. Then, we showed the perceptual effect of predictive coding: shape perception enhances perceived contrast. At last, we showed that predictive coding can use oscillations with different frequencies for feedforward and feedback. This thesis provided an innovative and viable neuronal mechanism for predictive coding and empirical evidence for excitatory predictive feedback and the close relationship between the predictive coding and oscillations
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李偉豪. "Hardware Implementation for Spike Sorting." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/61034842087278958232.
Повний текст джерелаАнотація:
碩士國立臺灣師範大學
資訊工程研究所
100
This paper presents a novel architecture for fast spike sorting. The architecture is based on Generalized Hebbian Algorithm (GHA) and Fuzzy C-Means (FCM) algorithm. The GHA are used for feature extraction and the FCM are used for clustering. To show the effectiveness of the circuit, the proposed architecture is physically implemented by Field Programmable Gate Array (FPGA). It is embedded in a System-On-Programmable-Chip (SOPC) platform for performance measurement. Experimental results show that the proposed architecture is an efficient spike sorting design for at-taining low classification error rate, low area costs and high speed computation.
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Wu, Cheng-You, and 吳承祐. "Software implementation of spike sorting system." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/65000911953816965384.
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陳昊. "Pipelined GHA Hardware Implementation for Spike Sorting." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/91990769286059410052.
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Wang, Kuo-Chuan, and 王國全. "Implementation of Handwritten Numeral Recognition in Space." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/10028335107564825731.
Повний текст джерелаАнотація:
碩士國立臺北教育大學
資訊科學系碩士班
101
This paper achieves the implementation of hand gesture digit recognition function by using the body motion sensor. The interactive motion-sensing technology is used to record the handwritten numerals in space. Then it converts the trajectories of handwritten numerals into corresponding shapes of digits. A feature matching method is also used to conduct the digit recognition. In the recognition process, the character area is used for extraction firstly. Then the image processing and recognition, binarization and Hilditch thinning algorithm are performed on the area of digits. The traversal and segmentation algorithm proposed by G.E.M.D.C. Bandara and S.D. Pathirana are also used to conduct segmentation of the skeleton area after thinning. The recognition’s result obtains by comparing the feature extraction and the feature database based on each character’s resulted segments. This paper proposes a concept of the interactive motion-sensing technology with trajectories of handwritten numerals to conduct digit recognition. And the conditions of identification of starter points can be improved. Therefore, this research can enhance the digit recognition rate and reduce the recognition time.
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Ko, Cheng-Wen, and 柯正雲. "Implementation of Automatic Spike Detection System for EEG." Thesis, 1998. http://ndltd.ncl.edu.tw/handle/31092700983815263148.
Повний текст джерелаАнотація:
碩士國立臺灣大學
電機工程學系研究所
86
An automatic spike detection algorithm for classification of multi-channelelec troencephalographic (EEG) signals based on artificial neural network is presen ted. Radial basis function (RBF) neural network was chosen for single channel recognition, with model optimization using receiver operating characteristics analysis. Waveform simplification was employed for high noise immunity. Fea ture extraction with as few as three parameters was used as preparation for th e inputs to the neural network. Identification of multi-channel geometric cor relation was performed to further lower the false-positive rate by using an in cidence matrix. Threshold value for spike classification was chosen for simul taneous maximization of detection sensitivity and selectivity. Evaluation wit h visual analysis in this preliminary study showed a 83% sensitivity using 16- channel continuous EEG records of four patients, while a high false positive r ate was found, which was believed to arise from the extensive andexhaustive vi sual analysis process. The computation time required for spike detection was significantly less than that needed for online display of the signals on the m onitor. We believe that the algorithm proposed in this study is robust and th at the simple structure of RBF neural network yields high potential for real-t ime implementation.
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McCurdy, Collin B. "A dual address space architecture : implementation and evaluation /." 2008. http://www.library.wisc.edu/databases/connect/dissertations.html.
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