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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.
151

Integrity as Part of a Manager¡¦s Professional Image Construct. A Mixed Methods Study

Gosling, Mark 19 December 2011 (has links)
Integrity in leadership is regarded as an important quality by the academic literature, by the practitioner and by the popular press alike. Given its lauded position this research argues that integrity is not just desirable in a manager, it is also an image desired by the manager and that it is a part the manager¡¦s professional image construction. This research uses a mixed methods approach to investigate integrity as an image goal and examines dispositional and situational factors on the manager¡¦s side of the relationship that effect the presentation of this image goal. Analysis of semi-structured interviews established that managers are aware of the importance of integrity and that it is seen both as a desirable image and in need of maintenance. Survey results found no main effects between behavioral integrity and the dispositional variable, self-monitoring. Investigating contingent factors this study showed that the relationship was moderated by job demands such that in situations of high job demands high self-monitors were perceived to be lower in behavioral integrity. Other contingent factors, multiple audiences and ethical guidelines, did not significantly moderate the relationship. The situational variable, distance, was shown to significantly affect the perception of the manager¡¦s integrity, where a reduction in distance led to an increase in behavioral integrity perceived by the subordinate. These results are discussed in combination with themes identified from the manager interviews and contribute to the understanding of the role of integrity for the manager and an understanding of how integrity is part of his professional image construct. The study indicated that while a manager may desire to present an image of integrity dispositional and situational factors might affect the success of this self-presentational goal. Implications and future research directions are presented.
152

An evaluation of membrane materials for the treatment of highly concentrated suspended salt solutions in reverse osmosis and nanofiltration processes for desalination

Hughes, Trenton Whiting 15 May 2009 (has links)
This thesis presents a study to enhance and improve a zero liquid discharge (ZLD) reverse osmosis process that uses seed crystals to promote crystallization of the dissolved salts in the residual brine while it is being treated by identifying those membrane materials that are most suitable for the process. In the study, a one plate SEPA Cell module by GE Osmonics was used to determine which membranes were most susceptible to fouling and/or membrane hydrolysis. A cellulose acetate (CA), polyamide (PA) low MWCO, and PA high MWCO membrane were tested under reverse osmosis conditions. The CA and thin film (TF) membranes were also tested for nanofiltration. The cell was operated under conditions that were determined to be optimum for each membrane by the manufacturer, GE Osmonics. A high pressure, low flow, positive displacement diaphragm pump circulated the saturated calcium sulfate solution with 2 % suspended solids through the cell while the reject and permeate were recycled back to the feed, thereby preserving a saturated solution to promote crystal growth and simulate the seeded reverse osmosis process. The temperature was maintained constant by adding an ice pack to the feed vessel when necessary. The transmembrane pressure differential was maintained constant by adjusting a back pressure valve on the concentrate outlet. The results illustrate that if potable drinking water is the intended use, then the nanofiltration cellulose acetate membrane should be used. If irrigation is the desired use, then the nanofiltration thin film membrane should be used. Overall, the reverse osmosis cellulose acetate membrane was observed to outperform all membranes when all performance parameters were normalized. However, this membrane was observed to be prone to degradation in a seeded slurry and therefore its lifetime should be analyzed further. The polyamide membrane initially had a high water transport coefficient, but fouling led to its rapid decline which was attributed to the membrane’s rough and protrusive surface. A lifetime test on the thin film and cellulose acetate revealed that when operated at their maximum pressure specified by GE Osmonics for a duration of 8 hours that no decrease in rejection occurred.
153

Time-Domain Methods for Synthesizing Broadband Macro-Models of Coupled Interconnects in High-Speed Digital Circuits

Kuo, Chun-Chih 12 July 2005 (has links)
This dissertation proposed two time-domain algorithms for extracting the broadband SPICE-compatible models of high-speed coupled interconnects. The first approach is proposed to synthesized the equivalent models of multi-conductor interconnects by cascading multiple configuration-oriented coupled transmission line (CCTL) units. The second approach focuses on the modeling of differential via based on a broadband macro-£k model with three modules represented by the optimum pole-residue forms. Using a systematic lumped-model extraction technique (SLET), all the pole-residue rational functions can transfer into a corresponding lumped model. The accuracy of the two algorithms is demonstrated both in time- and frequency -domain responses comparison with the direct 3D-FDTD simulation.
154

Methodology to quantify leaks in aerosol sampling system components

Vijayaraghavan, Vishnu Karthik 15 November 2004 (has links)
Filter holders and continuous air monitors (CAMs) are used extensively in the nuclear industry. It is important to minimize leakage in these devices and in recognition of this consideration, a limit on leakage for sampling systems is specified in ANSI/HPS N13.1-1999; however the protocol given in the standard is really germane to measurement of significant leakage, e.g., several percent of the sampling flow rate. In the present study, a technique for quantifying leakage was developed and that approach was used to measure the sealing integrity of a CAM and two kinds of filter holders. The methodology involves use of sulfur hexafluoride as a tracer gas with the device being tested operated under dynamic flow conditions. The leak rates in these devices were determined in the pressure range from 2.49 kPa (10 In. H2O) vacuum to 2.49 kPa (10 In. H2O) pressure at a typical flow rate of 56.6 L/min (2 cfm). For the two filter holders, the leak rates were less than 0.007% of the nominal flow rate. The leak rate in the CAM was less than 0.2% of the nominal flow rate. These values are well within the limit prescribed in the ANSI standard, which is 5% of the nominal flow rate. Therefore the limit listed in the ANSI standard should be reconsidered as lower values can be achieved, and the methodology presented herein can be used to quantify lower leakage values in sample collectors and analyzers. A theoretical analysis was also done to determine the nature of flow through the leaks and the amount of flow contribution by the different possible mechanisms of flow through leaks.
155

A Process Model of Applicant Faking on Overt Integrity Tests

Yu, Janie 14 January 2010 (has links)
To better understand the cognitive processes associated with faking behaviors, Ajzen?s Theory of Planned Behavior was adapted to the study of faking on overt integrity tests. This decision-based model is then expanded through the inclusion of a key outcome (counterproductive work behavior) and basic individual differences (conscientious personality and cognitive ability). Results from two student samples (n = 233 and n = 160) demonstrate that conscientiousness negatively predicts attitudes toward faking on employment tests, while cognitive ability predicts the ability to fake. In turn, faking ability moderates the effect of self-reported faking motive on actual test scores, while self-reported faking decreases the validity of integrity tests for predicting counterproductive work behaviors. Implications are discussed.
156

A Time Domain Approach for Effective Synthesizing of Broadband SPICE-Compatible Models of the Power Delivery Networks with Resonance Effect

Wang, Chen-chao 12 February 2008 (has links)
This dissertation proposed a novel time-domain algorithm for extracting the broadband SPICE-compatible models of power/ground planes with resonance effect. The time-domain algorithm approach can focus on the modeling of interconnectors and power/ground planes based on a broadband macro model. Every module of the broadband macro model is represented by the optimum pole-residue forms. Using a systematic lumped-model extraction technique, all the optimum pole-residue rational functions can be transferred into a corresponding lumped circuit model. The accuracy of the time-domain algorithms is demonstrated both in time- and frequency-domain responses comparison by the 3D-FDTD simulation and measurement. In addition, these models can be efficiently incorporated into the currently available circuit simulator such as HSpice for the consideration of power/ground bouncing noise with active devices in high-speed circuits.
157

Effects of Discontinuity Structures on EMI in Multi-Layer Printed Circuit Board Using Transmission Line Model

Yu, Ming-Hsuan 23 July 2008 (has links)
In this thesis, we study the discontinuity structure electromagnetic effect of multilayer printed circuit board in three sections. In first section, we introduced a modeling approach which is based on transmission line theory , and simulated with a series of test boards ,such as regular and irregular power delivery system and multilayer with via structure, finally ,we confirmed that the modeling approach is an efficient simulation and agreed fairly well with 3D full-wave method. In second section, we demonstrated the return current is disrupted at the via or broken at the power / ground plane with slots , the impedance becomes extremely high at the resonance frequencies of the power / ground plane cavity and via could be a major cause of the simultaneous switching noise generation, signal quality problem, and edge radiated emission in multi-layer PCB. In final section, we provided a effective reduction mechanism to eliminate the noise or EMI, which has been achieved using island with shorting vias and combining with the modeling approach can simulate and estimate effectively.
158

Research on Digitally Predistorted Power Amplifier and Injection-Pulled Oscillator for Wireless Communication System

Li, Chien-Jung 26 July 2009 (has links)
In a wireless communication system, the RF signal integrity is often deteriorated by power amplifier (PA) nonlinearity and local oscillator (LO) pulling. This dissertation attempts to study power amplifier and local oscillator with the deliberate input distortion or interference for understanding, and hence improving, the resultant RF signal integrity issues. Furthermore, the scope of this study is extended to explore novel wireless applications. Based on the above thoughts, this dissertation includes three topics. The first topic is devoted to a baseband digital predistortion technique for enhancing the power amplifier linearity in a wireless RF transmitter. A digital predistorter has been designed to compensate the amplitude and phase distortion due to the nature of PAs, and the predistortion can enhance the linearity of linear PAs as well as switching-mode PAs. The second topic proceeds with a rigorous analysis of a local oscillator subject to injection signal. A phase-locked loop (PLL) under injection is analyzed in frequency domain to account for the inherent band-pass filtering on an injection signal. Such analysis can further predict the effect of co-frequency or co-channel interference on the PLL phase noise. A discrete-time analysis is also provided to predict output spectra of the LO pulled by a sinusoidal and modulated injection signal. The final topic presents a novel RF sensing circuit for a cognitive radio to sense spectral environment using injection locking and frequency demodulation techniques. The proposed RF sensing circuit can fast and reliably detect frequency and power for analog and digital modulation signals. In addition, the sensing principle and circuit architecture are delivered on theoretical basis developed in this dissertation. A discrete time approach is also investigated to compute the sensed output signal.
159

Definition and measurement of stream health in Japan based on index of biological integrity (IBI) concepts /

Rossano, Eriko Morishita. January 2002 (has links)
Thesis (Ph. D.)--University of Washington, 2002. / Vita. Includes bibliographical references (leaves 105-115).
160

Do as I say, not as I do? Supervisory behavioral integrity, shared financial interests, and subordinate honesty in budget reporting

Zhang, Zhen 14 August 2015 (has links)
Participative budgeting plays an important role for information communication among hierarchies in organizations. In this study, I use a lab experiment to examine three research questions and investigate the role of supervisors in influencing subordinate honesty. First, I predict and find support that supervisory behavioral integrity, i.e. the alignment between a superior’s communication of a value of honesty and the superior’s behavioral honesty, is an effective informal control mechanism to influence employee honesty. However, the effectiveness of supervisory behavioral integrity in influencing employee honesty depends on the presence of shared financial interests between the superior and the subordinates, such that high supervisory behavioral integrity may promote employee honesty only in the presence of shared financial interests. In the absence of shared financial interests, supervisory behavioral integrity is no longer effective in influencing employee honesty. Finally, I investigate whether supervisory behavioral integrity, compared to supervisory behavioral honesty, has incremental effect on subordinate honesty. The results suggest that, compared to supervisory behavioral honesty, supervisory behavioral integrity has a stronger influence on subordinate honesty. Furthermore, high supervisory behavioral honesty is shown to have a demotion effect on subordinate honesty, i.e. subordinate honesty is lower when superior’s honesty is high than when it is low. Supplemental analysis provides potential explanations for the demotion effect. The implications of the findings for management accounting research and practice are discussed.

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