• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 1419
  • 370
  • 155
  • 140
  • 105
  • 92
  • 45
  • 32
  • 25
  • 18
  • 17
  • 15
  • 8
  • 6
  • 6
  • Tagged with
  • 2858
  • 1727
  • 814
  • 595
  • 507
  • 403
  • 399
  • 308
  • 294
  • 273
  • 270
  • 268
  • 246
  • 228
  • 208
  • 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.
921

The Relationship between Strength of Embeddedness Ties in Strategic Networks and the Innovation Performance: The Perspectives on Cournot Duopoly Competitive Game and Real Options

Wu, Guo-Ciang 04 June 2005 (has links)
Prior research on the strength of embeddedness ties in strategic networks in influencing innovation performance has produced inconsistent conclusions. In this paper, drawing on an investment perspective on firms¡¦ decision behavior, we argue that the ¡§control benefits¡¨¡Xanother characteristics of strategic networks¡Xalso affects firms¡¦ innovation performance. According to previous research, we adopt the speed of ¡§patent application¡¨ and ¡§market introduction of a new product¡¨ to measure innovation performance. Furthermore, we divide firms¡¦ innovation strategies into ¡§apply for a patent and introduce the new product to market later¡¨, ¡§patent the innovation and market introduction immediately¡¨ as well as ¡§introduce the new product to market and apply for a patent later¡¨. We examine the relationship between the strength of enbeddedness ties and firms¡¦ innovation performance using the theoretical frames of game theory and real options. After the analysis of Cournot duopoly game model and real options approach, several findings are acquired as follows: (a) the higher the strength of embeddedness ties, the more likely the firm is to abandon the innovation strategy ¡§apply for a patent and introduce the new product to market later¡¨ and adopt innovation strategies ¡§patent the innovation and market introduction immediately¡¨ or ¡§introduce the new product to market and apply for a patent later¡¨; (b) if the firm adopts the innovation strategy ¡§apply for a patent and introduce the new product to market later¡¨, then the strength of embeddedness ties has a positive effect on the speed of market introduction of the new product, but the relationship between the strength of embeddedness ties and the speed of patent application is not sure; (c) if the firm adopts innovation strategies ¡§patent the innovation and market introduction immediately¡¨ or ¡§introduce the new product to market and apply for a patent later¡¨, then the strength of embeddedness ties has both positive and negative impact on the speed of ¡§patent application¡¨ and ¡§market introduction of a new product¡¨, and therefore the relationship between the strength of embeddedness ties and the innovator¡¦s innovation performance is indeterminable. The research findings indicate that the innovator may delay the application for patent or postpone the launching of a new product because of the ¡§control benefits¡¨ derived from different strength of embeddedness ties. These results have broad implications for future research on strategic networks and innovation.
922

Comparison Of Analysis Methods Of Embedded Retaining Walls

Harmandar, Serkan 01 January 2007 (has links) (PDF)
ABSTRACT COMPARISON OF ANALYSIS METHODS OF EMBEDDED RETAINING WALLS HARMANDAR, Serkan M.S., Department of Civil Engineering Supervisor : Prof. Dr. Yener &Ouml / zkan Co -Supervisor : Dr. Oguz &Ccedil / aliSan December 2006, 123 pages In this study a single-propped embedded retaining wall supporting a cohesionless soil is investigated by four approaches, namely limit equilibrium, subgrade reaction, pseudo-finite element and finite element methods. Structural forces, such as strut loads, wall shear forces, bending moments are calculated by each method and results are compared. The analyses are carried for for three values of internal friction angle of soil / 30o, 35o, and 40o. Effects of modulus of soil elasticity of the backfill and wall stiffness on structural forces are investigated by using different values for these parameters. It is found that, in those of obtained by, limit equilibrium approach results in embedment depth greater than other methods. Minimum strut loads for the same soil and structure parameters are obtained by limit equilibrium method. An increase of Young&rsquo / s modulus of the soil results in decrease of the strut loads.
923

An Evaluation Of Aspect-oriented Programming For Embedded Real-time Systems

Kartal, Yusuf Bora 01 May 2007 (has links) (PDF)
Crosscutting concerns are the issues in software that cannot be modularized within a software module. In this thesis work, a detailed evaluation of the use of Aspect Oriented Programming for the implementation of crosscutting concerns in embedded real-time systems is presented. The pilot Audio Switch project implementations are first evaluated in terms of software quality attributes. Then a detailed analysis of the two implementations, according to embedded real-time performance metrics has been carried out. Evaluation results show the benefits of Aspect Oriented Programming in embedded real-time systems.
924

Effects Of Parallel Programming Design Patterns On The Performance Of Multi-core Processor Based Real Time Embedded Systems

Kekec, Burak 01 June 2010 (has links) (PDF)
Increasing usage of multi-core processors has led to their use in real time embedded systems (RTES). This entails high performance requirements which may not be easily met when software development follows traditional techniques long used for single processor systems. In this study, parallel programming design patterns especially developed and reported in the literature will be used to improve RTES implementations on multi-core systems. Specific performance parameters will be selected for assessment, and performance of traditionally developed software will be compared with that of software developed using parallel programming patterns.
925

Study of High Performance Circuits for 2.0V Embedded Dynamic Random Access Memory

Chen, Wei-Shiun 27 July 2000 (has links)
Abstract Four high-performance circuits design techniques for embedded DRAM are proposed. First, a negative voltage generator having high efficiency is proposed to provide the negative voltage for the modified word line driver. The negative voltage generator circuits could be manufactured in n-Well CMOS process, and its operation achieve optimal output voltage. When 2.0-V supplied voltage is applied, the output voltage of -1.6-V is obtained. Even though, the supplied voltage is scaled down to 1.5-V, the output voltage can still achieve -1.05-V. In contrast, the output voltage of traditional one under 2.0-V supplied voltage is only -0.67-V. Second, a fast wordline driver suitable for PMOS pass transistor is proposed. The wordline driver improves the turned-on time by 26.8ns compared with the traditional one and raises the operating speed by 79%. Third, a new reduced clock-swing driver is proposed. Under 2.0-V supplied voltage and 100MHz operating frequency, the total power consumption of the new driver working with RCSFF is reduced by 10% than that of traditional one working with RCSFF. For the above advantage of low power, the new driver is thus more suitable for embedded DRAM applications. Fourth, a modified hierarchical read bus amplifier is proposed. The read bus amplifier is based on the new sense-amplifier. It could drive the output by full-swing voltage. It improves the sensing speed by 2.1ns. And it got the same advantage of no dc idling current as the traditional N&PMOS cross-coupled amplifier. In this thesis, finally, the performance of these circuits is also integrated and examined in an 1-Kbit embedded DRAM test circuit. The simulation RAS access time of 27.9ns is achieved under 2.0V supplied voltage and loading of 16-Mbit embedded DRAM. This indicated the above proposed circuits could be applied in the low voltage and high speed embedded DRAM.
926

The Development Environment of Embedded System based on AMBA Platform

Wang, Wei-Cheng 23 January 2003 (has links)
In this paper, we proposed a hardware development environment of the Embedded system to reduce the complexity of the Embedded system archeitecture, fit the varied specification, decrease the difficulties and time consuming on hardware integration, and short the life period of products. According to the On-Cihp Bus platform, we can utilize certain modules repeatly and recofigure the parameters flexibily to integrate the necessary system hardware and complete the system verification rapidly that we can achieve the time to market. In this thesis, we discuss architecture of hardware platform and the technique of system integration. Further more; we introduce the concept of VRM (Verification Reuse Methodology) on the system verification that reduces the verification time of system.
927

Animating physical phenomena with embedded surface meshes

Wojtan, Chris 17 November 2010 (has links)
Accurate computational representations of highly deformable surfaces are indispensable in the fields of computer animation, medical simulation, computer vision, digital modeling, and computational physics. The focus of this dissertation is on the animation of physics-based phenomena with highly detailed deformable surfaces represented by triangle meshes. We first present results from an algorithm that generates continuum mechanics animations with intricate surface features. This method combines a finite element method with a tetrahedral mesh generator and a high resolution surface mesh, and it is orders of magnitude more efficient than previous approaches. Next, we present an efficient solution for the challenging problem of computing topological changes in detailed dynamic surface meshes. We then introduce a new physics-inspired surface tracking algorithm that is capable of preserving arbitrarily thin features and reproducing realistic fine-scale topological changes like Rayleigh-Plateau instabilities. This physics-inspired surface tracking technique also opens the door for a unique coupling between surficial finite element methods and volumetric finite difference methods, in order to simulate liquid surface tension phenomena more efficiently than any previous method. Due to its dramatic increase in computational resolution and efficiency, this method yielded the first computer simulations of a fully developed crown splash with droplet pinch off.
928

Resurssnålt kommunikationsprotokoll för små inbyggda system

Pettersson, Stefan January 2004 (has links)
<p>Web Services har vuxit i popularitet de senast åren. Användningen av inbyggda system</p><p>ökar också ständigt, och möjligheten att göra inbyggda system tillgängliga via Web Services öppnar nya möjligheter.</p><p>Detta arbete visar på möjligheter och problem med standardiserade textbaserade protokoll för kommunikation i inbyggda system med små resurser. XML-RPC och SOAP studeras ur detta perspektiv. SOAP befinns vara mer komplext att implementera stöd för än XMLRPC i den begränsade testmiljön, som har 32kB internminne. XML-RPC visar sig ge fördelar över proprietära protokoll främst när det gäller underhållbarhet och återanvändbarhet.</p>
929

Performance Evaluation of Embedded Microcomputers for Avionics Applications

Bilen, Celal Can, Alcalde, John January 2010 (has links)
<p>Embedded microcomputers are used in a wide range of applications nowadays. Avionics is one of these areas and requires extra attention regarding reliability and determinism. Thus, these issues should also be born in mind in addition to performance when evaluating embedded microcomputers.</p><p>This master thesis suggests a framework for performance evaluation of two members of the PowerPC microprocessor family, namely the MPC5554 from Freescale and PPC440EPx from AMCC, and analyzes the results within and between these processors. The framework can be generalized to be used in any microprocessor family, if required.</p><p>Apart from performance evaluation, this thesis also suggests also a new terminology by introducing the concept of determinism levels to be able to estimate determinism issues in avionics applications more clearly, which is crucial regarding the requirements and working conditions of this very application. Such estimation does not include any practical results as in performance evaluation, but rather remains theoretical. Similar to Automark™ used by AutoBench™ in the EEMBC Benchmark Suite, we introduce a new performance metric score that we call ”Aviomark” and we carry out a detailed comparison of Aviomark with the traditional Automark™ score to be able to see how Aviomark differs from Automark™ in behavior.</p><p>Finally, we have developed a graphical user interface (GUI) which works in parallel with the Green Hills MULTI Integrated Development Environment (IDE) in order to simplify and automate the evaluation process. By the help of the GUI, the users will be able to easily evaluate their specific PowerPC processors by starting the debugging from MULTI IDE.</p>
930

Durability of Embedded Fibre Optic Sensors in Composites

Levin, Klas January 2001 (has links)
<p>This thesis concerns various aspects of the durability offibre optic sensors embedded in composite. Since repair orreplacement of embedded sensors is not generally possible, thefunctional reliability of embedded sensors is one of the mostimportant prerequisites for successful use. The main researchobjective was to investigate the interaction between the sensorand the composite, and how this is affecting the mechanical andoptical sensor response. Fibre optic sensors embedded incomposite structures induce local stress concentrations whenthe composite is subjected to mechanical loads andenvironmental changes such as temperature and moisture. Acomplex transfer of stresses through the interfaces between theembedded sensor and the composite occurs and can result inlarge local stresses in the composite and a significant changein the response of the embedded sensor. These stressconcentrations make the interfaces susceptible todebonding.</p><p>The sensor performance was studied experimentally andnumerically. Some basic results were generated for the EFPI andBragg grating sensors. The phase-strain response was determinedduring static and fatigue loading. The results showed that thesensors were more reliable in compression than in tensilestatic and fatigue loading. Generally, the sensor reliabilityduring loading was significantly improved for the Bragg gratingsensors over that of the EFPI sensor, as an effect of thesensor geometry. This was also demonstrated in theinvestigations on impacts. Impacts do not necessarily result indamage in the composite, but might cause debonding or otherfailure modes in the sensor area. Large, local stressconcentrations occur at several positions in the EFPI sensor,which pointed out that this sensor type was not suitable forembedded applications.</p><p>The shift in focus from the sensor concept based on the EFPIsensor to that based on the Bragg grating sensor manifesteditself in several studies. The calculated deformation fieldaround an embedded optical fibre was verified in experimentsusing a high-resolution moiré interferometric technique.Furthermore, the improvement in the coating technology wasverified. A significant higher interfacial strength wasobtained with the silane-treated glass surface. The resultsindicated that at least a twofold improvement of the shearstrength was obtained.</p><p>To simultaneously measure the in-plane strain components andthe temperature change, embedded Bragg grating sensors werearranged in a rosette configuration. The relationship betweenthe optical response from each sensor and the strains in thelaminate was numerically and analytically established.</p><p>Damage lead to stress redistribution in the sensor region,which may influence the output from the embedded Bragg gratingsensor. The effect was numerically evaluated for interfacialdamage, and was compared to that of a sensor with undamagedinterface. The results showed that debonding might have asignificant influence, in particular for combined thermal andmechanical loading.</p><p><b>Keywords</b>: composites, fibre optic sensor, embedded, EFPIsensor, Bragg grating sensor, durability, fatigue, impact,strain measurement, interface, stress analysis</p>

Page generated in 0.0567 seconds