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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
101

Implementing Digital Logic Design Concepts Using Paper Electronics

Sah, Puja 05 1900 (has links)
This thesis presents the implementation of some of the basic concepts of digital logic design in a fun and creative way with the help of paper electronics. This involves circuit building on paper using conductive tape or conductive ink and circuit components as electronics craft materials. Paper electronics toolkit called circuit sticker microcontroller which is deployed by a company named Chibitronics and AT89C51 microcontroller were used for the computational functioning of the circuits built on paper. This can be used to teach the fundamentals of digital logic design to the students in their early stage of studies in an attractive way and can help them them gain a better understanding. This thesis can also be helpful in grabbing the attention of high school students and motivate them towards choosing the engineering discipline for their higher studies.
102

A CAD tool for current-mode multiple-valued CMOS circuits

Lee, Hoon S. 12 1900 (has links)
Approved for public release; distribution is unlimited / The contribution of this thesis is the development of a CAD (computer aided design) tool for current mode multiple-valued logic (MVL) CMOS circuits. It is only the second known MVL CAD tool and the first CAD tool for MVL CMOS. The tool accepts a specification of the function to be realized by the user, produces a minimal or near-minimal realization (if such a realization is possible), and produces a layout of a programmable logic array (PLA) integrated circuit that realizes the given function. The layout is in MAGIC format, suitable for submission to a chip manufacturer. The CAD tool also allows the user to simulate the realized function so that he/she can verify correctness of design. The CAD tool is designed also to be an analysis tool for heuristic minimization algorithms. As part of this thesis, a random function generator and statistics gathering package were developed. In the present tool, two heuristics are provided and the user can choose one or both. In the latter case, the better realization is output to the user. The CAD tool is designed to be flexible, so that future improvements can be made in the heuristic algorithms, as well as the layout generator. Thus, the tool can be used to accommodate new technologies, for example, a voltage mode CMOS PLA rather than the current mode CMOS currently implemented. / http://archive.org/details/cadtoolforcurren00leeh / Lieutenant, Republic of Korea Navy
103

Dizajn i minimizacija rekurzivnih Bulovih formula za memristivna logička kola / Logic design and minimization of recursive Boolean formulas for memristive circuits

Teodorović Predrag 02 July 2014 (has links)
<p>U radu je razmatran problem dizajna i minimizacije rekurzivne<br />Bulove formule konstruisane za proizvoljnu Bulovu funkciju y:BN<br />&rarr;B.<br />U cilju rešavanja ovog problema, predstavljene su dve algoritamske<br />heuristike za minimizaciju rekurzivne Bulove formule. Minimizacija<br />rekurzivne Bulove formule vrši se korišćenjem regularnih poredaka<br />pozitivnih proizvod termova. U disertaciji je dokazano kako je ova<br />regularnost poredaka zapravo potreban i dovoljan uslov da željena<br />Bulova funcija y bude korektno predstavljena rekurzivnom Bulovom<br />formulom konstruisanom na osnovu tih poredaka. Pokazano je i kako<br />predstavljeni algoritmi daju bolje rezultate za veći broj instanci<br />problema u poređenju sa algoritmima dostupnim u literaturi.</p> / <p>In this thesis, the problem of design and minimization of recursive Boolean<br />formula, based on an arbitrary Boolean function y:BN<br />&rarr;B , is considered. As a<br />solution of a problem, two heuristic algorithms that minimize the length of<br />recursive Boolean formula, were presented. Minimization, itself, is done by<br />using regular orders of positive product terms. In the thesis it was proved that<br />the regularity of orders represents necessary and sufficient condition for<br />correct representation of Boolean function y by recursive Boolean formula<br />based on such regular order. Developed algorithms are compared with other<br />heuristic algorithms for recursive Boolean formula minimization, available in<br />the literature, and it is shown how algorithms proposed in this thesis provide<br />better results for more problem instances.</p>
104

On general error cancellation based logic transformations: the theory and techniques. / 基於錯誤取消的邏輯轉換: 理論與技術 / CUHK electronic theses & dissertations collection / Ji yu cuo wu qu xiao de luo ji zhuan huan: li lun yu ji shu

January 2011 (has links)
Yang, Xiaoqing. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2011. / Includes bibliographical references (leaves 113-120). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.
105

Síntese de linguagens de descrição de arquitetura / Architecture description languages synthesis

Goto, Samuel Shoji Fukujima 17 August 2018 (has links)
Orientador: Rodolfo Jardim de Azevedo / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Computação / Made available in DSpace on 2018-08-17T02:11:17Z (GMT). No. of bitstreams: 1 Goto_SamuelShojiFukujima_M.pdf: 4578638 bytes, checksum: c8297ac26a037d8b90ccb1c1ad3d6c43 (MD5) Previous issue date: 2010 / Resumo: Desde sua popularização, processadores dobraram de capacidade e desempenho à cada dois anos. No entanto, paralelamente, essa tendência foi apenas sustentada pelo crescimento da sofisticação das implementações utilizadas. Atualmente, apesar de eficientes, processadores são complexos e difíceis de projetar. Para gerenciar esse problema, foram criadas linguagens chamadas ADLs que simplificam a especificação e simulação em níveis mais abstratos, enquanto HDLs ainda são utilizadas para a descrição RTL. Esse trabalho unifica o fluxo de especificação e simulação de processadores com o fluxo de implementação RTL a partir da mesma linguagem ADL. Para isso, escolhemos uma linguagem de descrição de arquitetura chamada ArchC. Sintetizamos com sucesso parte de processadores descritos em ArchC, como o PIC16F84, o I8051, o MIPS-I, o R3000 e uma JVM. Subconjuntos dos processadores foram prototipados em FPGA, com frequências de operação entre 80MHZ à 120MHZ projetados duas a três vezes mais rapidamente do que os desenvolvidos com HDLs. Mostramos que ArchC é sintetizável, completando o fluxo de projeto da linguagem até o nível RTL. Criamos as ferramentas necessárias e fornecemos modelos RTL dos processadores citados / Abstract: The design and implementation of processors is a complex task. Architecture Description Languages (ADLs) were created to extend existing HDLs to manage the inherit complexity of modern processors. Along with HDLs, they ease the development and prototyping of new architectures by providing a set of tools and algorithms to optimize and automate some of the tedious parts. However, while much has been done on using ADLs for simulating high level specifications, the academia knows very little about how to reuse them to implement real life processors. This work addresses the issues of synthesizing processors from an ADL model. To accomplish that, we chose an ADL called ArchC and we successfully synthesized pieces of its most stable models, like the PIC16F84, the i8051, the MIPS-I, the R3000 and a JVM. The processors were prototyped in FPGAs, with frequencies of operation as fast as 80MHZ to 120MHZ developed two to tree times faster compared to current approaches. We show that ArchC is in fact synthesizable, completing the design flow down to the RTL level. We provide all the necessary tools that were created to synthesize the models as well as the RTL models themselves / Mestrado / Arquitetura de Computadores / Mestre em Ciência da Computação
106

Estratégias de busca no projeto evolucionista de circuitos combinacionais

Manfrini, Francisco Augusto Lima 23 February 2017 (has links)
Submitted by Renata Lopes (renatasil82@gmail.com) on 2017-06-01T15:26:09Z No. of bitstreams: 1 franciscoaugustolimamanfrini.pdf: 2355106 bytes, checksum: 0c2126ac87b502d91fbb53cda2fa0b2a (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2017-06-02T15:56:42Z (GMT) No. of bitstreams: 1 franciscoaugustolimamanfrini.pdf: 2355106 bytes, checksum: 0c2126ac87b502d91fbb53cda2fa0b2a (MD5) / Made available in DSpace on 2017-06-02T15:56:42Z (GMT). No. of bitstreams: 1 franciscoaugustolimamanfrini.pdf: 2355106 bytes, checksum: 0c2126ac87b502d91fbb53cda2fa0b2a (MD5) Previous issue date: 2017-02-23 / A computação evolucionista tem sido aplicada em diversas áreas do conhecimento para a descoberta de projetos inovadores. Quando aplicada na concepção de circuitos digitais o problema da escalabilidade tem limitado a obtenção de circuitos complexos, sendo apontado como o maior problema em hardware evolutivo. O aumento do poder dos métodos evolutivos e da eficiência da busca constitui um importante passo para melhorar as ferramentas de projeto. Este trabalho aborda a computação evolutiva aplicada ao projeto de circuito lógicos combinacionais e cria estratégias para melhorar o desempenho dos algoritmos evolutivos. As três principais contribuições resultam dessa tese são: (i) o desenvolvimento de uma nova metodologia que ajuda a compreensão das causas fundamentais do sucesso/fracasso evolutivo;(ii)a proposta de uma heurística para a semeadura da população inicial; os resultados mostram que existe uma correlação entre a topologia da população inicial e a região do espaço de busca explorada; e (iii) a proposta de um novo operador de mutação denominado Biased SAM; verificou-se que esta mutação pode guiar de maneira efetiva a busca. Nos experimentos realizados o operador proposto é melhor ou equivalente ao operador de mutação tradicional. Os experimentos computacionais que validaram as respectivas contribuições foram feitos utilizando circuitos benchmark da literatura. / Evolutionary computation has been applied in several areas of knowledge for discovering Innovative designs. When applied to a digital circuit design the scalability problem has limited the obtaining of complex circuits, being pointed as the main problem in the evolvable hardware field. Increased power of evolutionary methods and efficiency of the search constitute an important step towards improving the design tool. This work approaches the evolutionary computation applied to the design of combinational logic circuits and createsstrategiestoimprovetheperformanceofevolutionaryalgorithms. The three main contributions result from this thesis are: (i) the developement of a methodology that helps to understand the success/failure of the genetic modifications that occur along the evolution; (ii) a heuristic proposed for seeding the initial population; the results showed there is a correlation between the topology of the initial population and the region of the search space which is explored. (iii) a proposal of a new mutation operator referred to as Biased SAM; it is verified that this operator can guide the search. In the experiments performed the mutation proposed is better than or equivalent to the traditional mutation. The computational experiments that prove the efficiency of the respective contributions were made using benchmark circuits of the literature.
107

Multi-processor logic simulation at the chip level

Roumeliotis, Emmanuel January 1986 (has links)
This dissertation presents the design and development of a multi-processor logic simulator. After an introduction to parallel processing, the concept of distributed simulation is described as well as the possibility of deadlock in a distributed system. It is proven that the proposed system does not deadlock. Next, the modeling techniques are discussed along with the timing mechanisms used for logic simulation. A new approach, namely process oriented simulation is studied in depth. It is shown that modeling for this kind of simulation is more efficient regarding modeling ease, computer memory and simulation time, than existing simulation methods. The hardware design of the multi-processor system and the algorithms for synchronization and signal interchange between the processors are presented next. An algorithm for an efficient partitioning of the digital network to be simulated among the processors of the system is also described. Apart from the simulation of a single digital network, the simulator can also be used for fault simulation and design verification. Regarding fault simulation, the fault injection and fault detection techniques are presented. The experimental results obtained by running the multi-processor simulator are compared with the theoretical estimates as well as with results obtained by other multi-processor systems. The comparison shows that the proposed simulator exhibits the estimated performance. Finally, the design of a common bus interface is given. This interface will connect the processors of the system directly without the intervention of a hard disk which was used for the development and testing of the system. / Ph. D.
108

Gene expression programming for logic circuit design

Masimula, Steven Mandla 02 1900 (has links)
Finding an optimal solution for the logic circuit design problem is challenging and time-consuming especially for complex logic circuits. As the number of logic gates increases the task of designing optimal logic circuits extends beyond human capability. A number of evolutionary algorithms have been invented to tackle a range of optimisation problems, including logic circuit design. This dissertation explores two of these evolutionary algorithms i.e. Gene Expression Programming (GEP) and Multi Expression Programming (MEP) with the aim of integrating their strengths into a new Genetic Programming (GP) algorithm. GEP was invented by Candida Ferreira in 1999 and published in 2001 [8]. The GEP algorithm inherits the advantages of the Genetic Algorithm (GA) and GP, and it uses a simple encoding method to solve complex problems [6, 32]. While GEP emerged as powerful due to its simplicity in implementation and exibility in genetic operations, it is not without weaknesses. Some of these inherent weaknesses are discussed in [1, 6, 21]. Like GEP, MEP is a GP-variant that uses linear chromosomes of xed length [23]. A unique feature of MEP is its ability to store multiple solutions of a problem in a single chromosome. MEP also has an ability to implement code-reuse which is achieved through its representation which allow multiple references to a single sub-structure. This dissertation proposes a new GP algorithm, Improved Gene Expression Programming (IGEP) which im- proves the performance of the traditional GEP by combining the code-reuse capability and simplicity of gene encoding method from MEP and GEP, respectively. The results obtained using the IGEP and the traditional GEP show that the two algorithms are comparable in terms of the success rate when applied on simple problems such as basic logic functions. However, for complex problems such as one-bit Full Adder (FA) and AND-OR Arithmetic Logic Unit (ALU) the IGEP performs better than the traditional GEP due to the code-reuse in IGEP / Mathematical Sciences / M. Sc. (Applied Mathematics)
109

Integrated Circuits Based on Individual Single-Walled Carbon Nanotube Field-Effect Transistors

Ryu, Hyeyeon 05 November 2012 (has links) (PDF)
This thesis investigates the fabrication and integration of nanoscale field-effect transistors based on individual semiconducting carbon nanotubes. Such devices hold great potential for integrated circuits with large integration densities that can be manufactured on glass or flexible plastic substrates. A process to fabricate arrays of individually addressable carbon-nanotube transistors has been developed, and the electrical characteristics of a large number of transistors has been measured and analyzed. A low-temperature-processed gate dielectric with a thickness of about 6 nm has been developed that allows the transistors and circuits to operate with voltages of about 1.5 V. The transistors show excellent electrical properties, including a large transconductance (up to 10 µS), a large On/Off ratio (>10^4), a steep subthreshold swing (65 mV/decade), and negligible leakage currents (~10^-13 A). For the realization of unipolar logic circuits, monolithically integrated load resistors based on high-resistance metallic carbon nanotubes or vacuum-evaporated carbon films have been developed and analyzed by four-probe and transmission line measurements. A variety of combinational logic circuits, such as inverters, NAND gates and NOR gates, as well as a sequential logic circuit based on carbon-nanotube transistors and monolithically integrated resistors have been fabricated on glass substrates and their static and dynamic characteristics have been measured. Optimized inverters operate with frequencies as high as 2 MHz and switching delay time constants as short as 12 ns. / Thema dieser Arbeit ist die Herstellung und Integration von Feldeffekt-Transistoren auf der Grundlage einzelner halbleitender Kohlenstoffnanoröhren. Solche Bauelemente sind zum Beispiel für die Realisierung integrierter Schaltungen mit hoher Integrationsdichte auf Glassubstraten oder auf flexiblen Kunststofffolien von Interesse. Zunächst wurde ein Herstellungsverfahren für die Anfertigung einer großen Anzahl solcher Transistoren auf Glas- oder Kunststoffsubstraten entwickelt, und deren elektrische Eigenschaften wurden gemessen und ausgewertet. Das Gate-Dielektrikum dieser Transistoren hat eine Schichtdicke von etwa 6 nm, so das die Versorgungsspannungen bei etwa 1.5 V liegen. Die Transistoren haben sehr gute elektrische Parameter, z.B. einen großen Durchgangsleitwert (bis zu 10 µS), ein großes Modulationsverhältnis (>10^4), einen steilen Unterschwellanstieg (65 mV/Dekade) und vernachlässigbar kleine Leckströme (~10^-13 A). Für die Realisierung unipolarer Logikschaltungen wurden monolithisch integrierte Lastwiderstände auf der Grundlage metallischer Kohlenstoffnanoröhren mit großem Widerstand oder mittels Vakuumabscheidung erzeugter Kohlenstoffschichten entwickelt und u. a. mittels Vierpunkt- und Transferlängen-Messungen analysiert. Eine Reihe kombinatorischer Schaltungen, z.B. Inverter, NAND-Gatter und NOR-Gatter, sowie eine sequentielle Logikschaltung wurden auf Glassubstraten hergestellt, und deren statische und dynamische Parameter wurden gemessen. Optimierte Inverter arbeiten bei Frequenzen von bis zu 2 MHz und haben Signalverzögerungen von lediglich 12 ns.
110

Automated Generation of Round-robin Arbitration and Crossbar Switch Logic

Shin, Eung Seo 25 November 2003 (has links)
The objective of this thesis is to automate the design of round-robin arbiter logic. The resulting arbitration logic is more than 1.8X times faster than the fastest prior state-of-the-art arbitration logic the author could find reported in the literature. The generated arbiter implemented in a single chip is fast enough in 0.25ьm CMOS technology to achieve terabit switching with a single chip computer network switch. Moreover, this arbiter is applicable to crossbar (Xbar) arbitration logic. The generated Xbar, customized according to user specifications, provides multiple communication paths among masters and slaves. As the number of transistors on a single chip increases rapidly, there is a productivity gap between the number of transistors available in a chip and the number of transistors per hour a chip designer designs. One solution to reduce this productivity gap is to increase the use of Silicon Intellectual Property (SIP) cores. However, a SIP core should be customized before being used in a system different than the one for which it was designed. Thus, to reconfigure the SIP core, either an engineer must spend significant effort altering the core by hand or else an enhanced CAD tool can automatically customize the core according to customer specifications. In this thesis, we present SIP generator tools for arbiter and Xbar generation. First, we introduce a Round-robin Arbiter Generator (RAG). The RAG can generate a hierarchical Bus Arbiter (BA) which is faster than all known previous approaches. RAG can also generate a hierarchical Switch Arbiter (SA) which is faster than all known previous approaches. Using a 0.25ьm TSMC standard cell library from LEDA Systems, we show the arbitration time of a 32x32 SA and demonstrate that our SA meets the time constraint to achieve terabit throughput. Furthermore, using a novel token-passing hierarchical arbitration scheme, our 32x32 SA performs better than the Ping-Pong Arbiter and Programmable Priority Encoder by factors of 1.8X and 2.3X, respectively, with less power dissipation. Finally, we present an Xbar switch Generator (X-Gt) tool that automatically configures a crossbar for a multiprocessor System-on-a-Chip (SoC). An Xbar is generated in Register Transfer Level (RTL) Verilog HDL.

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