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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

Automated Construction of Macromodels from Frequency Data for Simulation of Distributed Interconnect Networks

Min, Sung-Hwan 12 April 2004 (has links)
As the complexity of interconnects and packages increases and the rise and fall time of the signal decreases, the electromagnetic effects of distributed passive devices are becoming an important factor in determining the performance of gigahertz systems. The electromagnetic behavior extracted using an electromagnetic simulation or from measurements is available as frequency dependent data. This information can be represented as a black box called a macromodel, which captures the behavior of the passive structure at the input/output ports. In this dissertation, the macromodels have been categorized as scalable, passive and broadband macromodels. The scalable macromodels for building design libraries of passive devices have been constructed using multidimensional rational functions, orthogonal polynomials and selective sampling. The passive macromodels for time-domain simulation have been constructed using filter theory and multiport passivity formulae. The broadband macromodels for high-speed simulation have been constructed using band division, selector, subband reordering, subband dilation and pole replacement. An automated construction method has been developed. The construction time of the multiport macromodel has been reduced. A method for reducing the order of the macromodel has been developed. The efficiency of the methods was demonstrated through embedded passive devices, known transfer functions and distributed interconnect networks.
102

Analysis and Design for the Electromagnetic Susceptibility of High-Speed Digital Circuits

Kuo, Hung-chun 28 June 2006 (has links)
With the enormously developing of the wireless communication technology, the electromagnetic environment exposing to the electrical devices is becoming more and more complex. Besides, the trends of designing high-speed digital computer systems are toward fast edge rates, high clock frequencies, and low voltage levels. The electromagnetic susceptibility (EMS) or immunity of the high-speed circuit has become an important issue today apparently. In this thesis, we will firstly establish the measurement environment and calibration technology for numerical validation. Then we employ the three-dimension finite-differential time-domain (3D-FDTD) numerical method compared to the finite element method (FEM) to simulate the EMS behavior of the power delivery network (PDN) and traces of the printed circuit boards (PCB). In addition to several types of layout of the traces studied in this thesis, we also explain the mechanism and phenomenon of the EMS of the power/ground planes of the PCB. Besides the EMS behavior research of the traditional solutions to suppress the power noise, we propose an electromagnetic bandgap structure (EBG) which has the broadband suppression of the power noise and is validated to be effective to improve the EMS problems. Finally, we also propose a novel concept to increase the signal integrity (SI) by shielding design.
103

The Impact of Leader¡¦s Integrity Character on the Effec- tiveness of Organization Change --- A Case of Formosa Plastics Corporation, Taiwan Semiconductor Manufacturing Company, and Macronix International

Lai, Shih-Chung 02 February 2007 (has links)
The Impact of Leader¡¦s Integrity Character on the Effectiveness of Organization Change --- A Case of Formosa Plastics Corporation, Taiwan Semiconductor Manufacturing Company, and Macronix International Student : Lai, Shih-Chung Advisor : Dr. Huang , Jason H. National Sun Yat¡V Sen University Department of Business Management Abstract Integrity is one of the key factors to organizational change and it long standing. It is also a highly emphasized issue in corporate governance. Across the world, business misconducts that have caused severe consequences to the economy and society are increasing each day, and the level of trust on the businesses worsens after each event. The objective of this study is to investigate the impact of the integrity orientation of the leaders on organizational change, on the innovation which leads to a new stage of growth. The study is conducted through literature review and case analyses. I probe into the factors that impact the effectiveness of organization change. The study focused on the leader's character of integrity. The findings are as follow. 1.Integrity character bears a high degree of influence on the organization change process. The more intense the changes, the more it should be initiated from the top down, and the more important is the leadership. 2.The strength of crisis consciousness drives organization change, and further the demand on leader¡¦s integral character, no matter it's a stable enterprise or the one under change. 3.The best prediction model for the integrity character of leaders is the long term coworker observation. The same model would apply for selecting and fostering successors. 4.By observing the consistency between leader's oral expression and actual behavior is sufficiently indicative of the suitability of the lesders. 5.There are three critical dimensions of the character of integrity, which this study referred to as the three components of integrity, that is, ¡§righteousness and the belief of integrity¡¨,¡§consistency in thought and words¡¨, and ¡§consistency between words and behaviors¡¨. ¡iKeyword¡j¡G Integrity Character, Organizational change, Righteousness , Integrity, Consistency between Thought and Words, Consistency between Words and Behaviors.
104

Managing signal and power integrity using power transmission lines and alternative signaling schemes

Telikepalli, Satyanarayana 08 June 2015 (has links)
In this dissertation, a new signaling scheme known as Constant Voltage Power Transmission Line (CV-PTL) is presented to supply power to a digital I/O circuit. This signaling scheme provides power through a transmission line in place of a power plane while dynamically changing the impedance of the power delivery network to keep a constant voltage at the power pin of the IC. Consequently, this reduces the effects of return path discontinuities and can improve the quality of output signal by reducing power and ground bounce. Through theory, simulation, and measurements, we show that this new method can be used to reduce jitter and eye height with the proposed PDN methodology. In addition, the signaling scheme was extended to vertically-stacked 3D integrated circuits (3D ICs). It is known that power supply noise worsens as one goes higher up in the stack of dies due to increased interconnect inductance. However, by utilizing the CV-PTL concept in the PDN design of a 3-layer 3DIC system, the circuit showed considerable improvement in power supply noise and peak-to-peak jitter as compared to the conventional design approach. In addition to signal and power integrity of these signaling schemes, the noise coupling between digital and RF components is also investigated. A simple design for mitigating the coupling of power supply noise in mixed-signal electronics is presented. Currently used methods, such as electromagnetic bandgap structures have been shown to exhibit excellent noise isolation characteristics, and are a popular area of research in this area. However, these structures can pose difficulties for signal integrity. The proposed method extends the previous power transmission line work to address both the power supply noise generation and isolation. Test vehicles using these proposed methods, as well as using an EBG structure were fabricated and tested with regards to power supply noise, jitter, and noise isolation. The proposed methods show significant improvements in almost all performance metrics as compared to EBG. Finally, this dissertation discusses the effect of implementing a power transmission line in a power distribution network composed of a switching regulator and a voltage regulator module. The DC conductor losses of the PTL can not only affect power efficiency of the entire system, but can also affect the proper operation of the linear regulator module when supporting large currents. Consequently, recommendations are made on the design of the PTL to ensure proper operation and efficiency.
105

The Relationship Between Secondary School Teachers' Perceptions of Principal Ethical Leadership and Organizational Health

Chambers, Jessica H 01 December 2011 (has links)
The purpose of this descriptive, correlational study was to determine if any significant relationships existed between secondary school teachers’ perceptions of principal leader integrity as measured by the Perceived Leadership Integrity Scale ([PLIS], Craig & Gustafson, 1998) and schools’ organizational health as perceived by secondary school teachers and gauged by the Organizational Health Inventory for Secondary Schools ([OHI-S], Hoy & Feldman, 1987). The study also explored the seven OHI-S dimensions: (1) Institutional Integrity, (2) Initiating Structure, (3) Consideration, (4) Principal Influence, (5) Resource Support, (6) Morale, and (7) Academic Emphasis—and their relationships with the demographics of the sample. The sample involved six hundred fifty (650) Tennessee secondary school teachers identified through a purposive sampling process. These teachers completed both surveys and the requested demographic questionnaire online. Pearson product correlations revealed statistically significant relationships between Perceived Leader Integrity (PLI) and the composite score calculated from the scores of the seven OHI-S dimensions—the Organizational Health Index (OH Index), as well as between PLI and each of the seven OHI-S dimensions. Multiple regression analysis provided closer scrutiny of the data. In terms of the seven dimensions on PLI, this analysis showed the OH Index to have a moderate direct relationship, Consideration to be the strongest indicator, and Institutional Integrity and Academic Emphasis to a have a smaller, but statistically significant relationships. Univariate and multivariate analysis of variance tests were conducted to determine differences between and among PLI, the OH Index, and the demographic variables. Subject taught was strongly significant in relation to the seven OHI-S dimensions. The Tukey HSD and the Bonferroni correction were performed to examine more closely the significant differences found to exist among educational level or total years of teaching experience and the OH Index, as well as each of its seven dimensions. These findings help broaden understanding of the relationship between leadership and ethics. Northouse (2004) suggests that clarification of this relationship can identify implications for policy and decision making. Future research should explore the use of longitudinal or qualitative research methodology to study PLI and organizational health in greater depth.
106

[pt] MONITORAMENTO DE RISERS FLEXÍVEIS COM SENSORES A FIBRA ÓPTICA / [en] MONITORING FLEXIBLE RISERS WITH OPTICAL FIBER SENSORS

20 October 2011 (has links)
[pt] O interesse no monitoramento da integridade estrutural de risers flexíveis tem crescido significativamente nos últimos anos. Para dutos que já estão atingindo sua vida de projeto, sistemas de monitoramento podem fornecer alertas antecipados de possíveis falhas e também auxiliar o operador na programação de paradas para manutenção. Diferentes técnicas estão sendo testadas pelos operadores de dutos flexíveis tais como inspeção visual automatizada, monitoramento de vibrações e emissão acústica, além de técnicas baseadas em métodos eletromagnéticos. Algumas destas técnicas já estão sendo implementadas em unidades de exploração e produção marítimas no Brasil e em outros países. A presente contribuição aborda o monitoramento contínuo e em tempo real utilizando sensores a fibra óptica (Redes de Bragg) para detectar a ruptura dos arames nas armaduras de tração de risers flexíveis. Duas linhas são seguidas, monitoramento direto e monitoramento indireto. O monitoramento indireto consiste na instrumentação da capa polimérica do riser, de forma não intrusiva, e avalia possíveis alterações na mesma, causadas pelo rompimento dos arames. Para isso foi desenvolvido um transdutor, denominado Colar 3D, capaz de detectar variações no diâmetro externo, elongação e torção no duto. A técnica de monitoramento direto é denominada MODA (Monitoramento Óptico Direto nos Arames). Nesta técnica os arames são instrumentados individualmente com os sensores ópticos, que monitoram as tensões/deformações dos mesmos, assim, rompimentos de arames e comportamentos inesperados podem ser facilmente detectados. Resultados de ensaios em escala real mostraram que a probabilidade de detecção do monitoramento indireto aumenta significativamente quando o sistema é empregado em conjunto com outros tipos de monitoramento indireto. Os resultados de laboratório para o monitoramento direto apontaram alta sensibilidade e confiabilidade do sistema, que já foi instalado em três plataformas operadas pela Petrobra na Bacia de Campos. / [en] The interest in structural health monitoring of flexible risers has grown significantly in recent years. For ducts that are already reaching their design life, monitoring systems can provide early warnings of potential failures and also assist the operator in scheduling downtime. Different techniques are being tested by operators of flexible pipes such as automated visual inspection, vibration monitoring and acoustic emission, in addition to techniques based on electromagnetic methods. Some of these techniques are already being implemented in units of maritime exploration and production in Brazil and other countries. This contribution discusses the continuous monitoring and real-time using optical fiber sensors (FBGs) to detect the breaking of wires in the tensile armor of flexible risers. Two lines are followed, direct monitoring and indirect monitoring. The proposed indirect monitoring technique consists in the nonintrusive instrumentation of the riser’s polymeric outer sheath, which will provide strain signals that change due to the breaking of wires in the armor layer. For that, a transducer capable of detecting variations in the outer diameter, as well as stretching and twisting in the duct was developed. In the direct monitoring technique, all the wires in the external armor layer are individually instrumented with optical sensors that continuously monitor their strains, so that any disruptions of wires and unexpected behavior can be easily detected. Results of full scale laboratory tests showed that the probability of detection of indirect monitoring increases significantly when the system is used in conjunction with other types of indirect monitoring. The laboratory results for the direct monitoring showed high sensitivity and reliability of the system, which has already been installed in three oil rigs operated by Petrobras in the Campos Basin.
107

A NEW APPROACH TO DYNAMIC INTEGRITY CONTROL

Albalawi, Talal S. 20 April 2016 (has links)
No description available.
108

Modeling and simulation for signal and power integrity of electronic packages

Choi, Jae Young 06 November 2012 (has links)
The objective of this dissertation is to develop electrical modeling and co-simulation methodologies for signal and power integrity of package and board applications. The dissertation includes 1) the application of the finite element method to the optimization for decoupling capacitor selection and placement on a power delivery network (PDN), 2) the development of a PDN modeling method effective for multidimensional and multilayer geometries, 3) the analysis and modeling of return path discontinuities (RPDs), and 4) the implementation of the absorbing boundary condition for PDN modeling. The optimization technique for selection and placement of decoupling capacitors uses a genetic algorithm (GA) and the multilayer finite element method (MFEM), a PDN modeling method using FEM. The GA is customized for the decoupling problem to enhance the convergence speed of the optimization. The mathematical modifications necessary for the incorporation of the capacitor model into MFEM is also presented. The main contribution of this dissertation is the development of a new modeling method, the multilayer triangular element method (MTEM), for power/ground planes of a PDN. MTEM creates a surface mesh on each plane-pair using dual graphs; a non-uniform triangular mesh (Delaunay triangulation) and its orthogonal counterpart (Voronoi diagram), to which electromagnetic and equivalent circuit concepts are applied. The non-uniform triangulation is especially efficient for discretizing multidimensional and irregular geometries which are common in package and board PDNs. Moreover, MTEM generates a sparse, banded, and symmetric system matrix, which enables efficient computations. For a given plane-pair, MTEM extracts an equivalent circuit that is consistent with the physics-based planar-circuit model of a plane-pair. Thus, the values of the lumped elements can be simply calculated from the physical parameters, such as material properties and mesh geometries of each unit-cell. Consequently, the modeling of MTEM is flexible and easy to modify for further extensions, such as the incorporation of external circuits, e.g. decoupling capacitors and vertical interconnects. Power and ground planes provide paths for the return current of signal traces. Typically, planes have discontinuities such as via holes, plane cutouts, and split planes that disturb flow of signal return currents. At the discontinuity, return currents have to detour or switch to different layers, causing signal and power integrity problems. Therefore, a separate analysis of signal interconnects will neglect the significant coupling with a PDN, and the result will not be reliable. In this dissertation, the co-simulation of the signal and power integrity is presented focusing on the modeling of RPDs created by split planes, apertures, and vias. Plane resonance is one of the main sources of power integrity problems in package and board PDNs. A number of techniques have been developed and published in literature to reduce or prevent the resonance of a plane-pair. One of the techniques is to surround plane-pair edges with absorbing material that effectively damps the outgoing parallel-plate wave and minimizes the reflection. To model this behavior, the boundary condition of MTEM needs to be changed from its original form, the open-circuit boundary condition. In this dissertation, the application of the 1st order absorbing boundary condition to MTEM is presented.
109

Anti-money laundering regulations and the effective use of mobile money in South Africa / Marike Kersop

Kersop, Marike January 2014 (has links)
Mobile financial services, specifically mobile money, has the potential to expand access to financial services to millions of unbanked people in South Africa. As such, it looks very promising in terms of financial inclusion. However, concerns exist that mobile money can be detrimental to financial integrity since there are several proven risk factors linked to mobile financial services. These risk factors make mobile money very susceptible to money laundering. The potential for abuse and the need for appropriate controls is therefore something which cannot be ignored. While the South African legislator has made provision for comprehensive anti-money laundering preventative measures by means of the Financial Intelligence Centre Act 38 of 2001, there exists no South African legislation explicitly concerned with mobile money. It is therefore difficult to determine what the regulatory stance is in terms of mobile money in South Africa. The Financial Action Task Force (FATF) is, however, currently focusing attention on the effect which mobile money may have on financial integrity. The latest FATF Recommendations make provision for several anti-money laundering controls which are specifically applicable to mobile money, including controls regarding money or value transfer services and new technologies. While it is always difficult to balance financial integrity and financial inclusion, the risk-based approach makes it possible for governments to implement effective antimoney laundering measures, thereby preserving financial integrity, without the need to compromise on financial inclusion objectives. The fact that South Africa has not fully adopted a risk-based approach is a problem which needs to be addressed if mobile money is to deliver on its promises for financial inclusion, without being detrimental to financial integrity. / LLM (Import and Export Law), North-West University, Potchefstroom Campus, 2015
110

Anti-money laundering regulations and the effective use of mobile money in South Africa / Marike Kersop

Kersop, Marike January 2014 (has links)
Mobile financial services, specifically mobile money, has the potential to expand access to financial services to millions of unbanked people in South Africa. As such, it looks very promising in terms of financial inclusion. However, concerns exist that mobile money can be detrimental to financial integrity since there are several proven risk factors linked to mobile financial services. These risk factors make mobile money very susceptible to money laundering. The potential for abuse and the need for appropriate controls is therefore something which cannot be ignored. While the South African legislator has made provision for comprehensive anti-money laundering preventative measures by means of the Financial Intelligence Centre Act 38 of 2001, there exists no South African legislation explicitly concerned with mobile money. It is therefore difficult to determine what the regulatory stance is in terms of mobile money in South Africa. The Financial Action Task Force (FATF) is, however, currently focusing attention on the effect which mobile money may have on financial integrity. The latest FATF Recommendations make provision for several anti-money laundering controls which are specifically applicable to mobile money, including controls regarding money or value transfer services and new technologies. While it is always difficult to balance financial integrity and financial inclusion, the risk-based approach makes it possible for governments to implement effective antimoney laundering measures, thereby preserving financial integrity, without the need to compromise on financial inclusion objectives. The fact that South Africa has not fully adopted a risk-based approach is a problem which needs to be addressed if mobile money is to deliver on its promises for financial inclusion, without being detrimental to financial integrity. / LLM (Import and Export Law), North-West University, Potchefstroom Campus, 2015

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