To see the other types of publications on this topic, follow the link: Empirical equation.
Dissertations / Theses on the topic 'Empirical equation'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 dissertations / theses for your research on the topic 'Empirical equation.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.
1
Yuan, Yiyong Kolenikov Stanislav. "Empirical likelihood approach estimation of structural equation models." Diss., Columbia, Mo. : University of Missouri--Columbia, 2007. http://hdl.handle.net/10355/5029.
Full textAbstract:
The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file. Title from PDF of title page (University of Missouri--Columbia, viewed on September 15, 2009). Thesis advisor: Dr. Stanislav Kolenikov. Includes bibliographical references.
2
Romijn, Reinout Carel [Verfasser]. "Empirical Model Reduction of Differential-Algebraic Equation Systems / Reinout Carel Romijn." Aachen : Shaker, 2016. http://d-nb.info/1084536692/34.
Full text
3
Romijn, Reinout [Verfasser]. "Empirical Model Reduction of Differential-Algebraic Equation Systems / Reinout Carel Romijn." Aachen : Shaker, 2016. http://nbn-resolving.de/urn:nbn:de:101:1-201602282397.
Full text
4
Dhuttargaon, Mukund S. Cheraghi S. Hossein. "An empirical tool life equation for diamond interlocked tool based on delamination." Diss., A link to full text of this thesis in SOAR, 2007. http://soar.wichita.edu/dspace/handle/10057/1126.
Full textAbstract:
Thesis (M. S.)--Wichita State University, College of Engineering, Dept. of Industrial and Manufacturing Engineering."May 2007." Title from PDF title page (viewed on Dec. 20, 2007). Thesis adviser: S. Hossein Cheraghi. Includes bibliographic references (73-76 leaves).
5
Lu, Yinghua. "Empirical Likelihood Inference for the Accelerated Failure Time Model via Kendall Estimating Equation." Digital Archive @ GSU, 2010. http://digitalarchive.gsu.edu/math_theses/76.
Full textAbstract:
In this thesis, we study two methods for inference of parameters in the accelerated failure time model with right censoring data. One is the Wald-type method, which involves parameter estimation. The other one is empirical likelihood method, which is based on the asymptotic distribution of likelihood ratio. We employ a monotone censored data version of Kendall estimating equation, and construct confidence intervals from both methods. In the simulation studies, we compare the empirical likelihood (EL) and the Wald-type procedure in terms of coverage accuracy and average length of confidence intervals. It is concluded that the empirical likelihood method has a better performance. We also compare the EL for Kendall’s rank regression estimator with the EL for other well known estimators and find advantages of the EL for Kendall estimator for small size sample. Finally, a real clinical trial data is used for the purpose of illustration.
6
Stripling, Gwendolyn D. "An Empirical Assessment of Energy Management Information System Success Using Structural Equation Modeling." NSUWorks, 2017. http://nsuworks.nova.edu/gscis_etd/1019.
Full textAbstract:
The Energy Industry utilizes Energy Management Information Systems (EMIS) smart meters to monitor utility consumers’ energy consumption, communicate energy consumption information to consumers, and to collect a plethora of energy consumption data about consumer usage. The EMIS energy consumption information is typically presented to utility consumers via a smart meter web portal. The hope is that EMIS web portal use will aid utility consumers in managing their energy consumption by helping them make effective decisions regarding their energy usage. However, little research exists that evaluates the effectiveness or success of an EMIS smart meter web portal from a utility consumer perspective. The research goal was to measure EMIS smart meter web portal success based on the DeLone and McLean Information Success Model. The objective of the study was to investigate the success constructs system quality, information quality, service quality, use, and user satisfaction, and determine their contribution to EMIS success, which was measured as net benefits. The research model used in this study employed Structural Equation Modeling (SEM) based on Partial Least Squares (PLS) to determine the validity and reliability of the measurement model and to evaluate the hypothetical relationships in the structural model. The significant validity and reliability measures obtained in this study indicate that the DeLone and McLean Information Success Model (2003) has the potential for use in future EMIS studies. The determinants responsible for explaining the variance in net benefits were EMIS use and user satisfaction. Based on the research findings, several implications and future research are stated and proposed.
7
Brown, Chad M. "An Empirical Test of the Nontraditional Undergraduate Student Attrition Model Using Structural Equation Modeling." Ohio University / OhioLINK, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1176485072.
Full text
8
Romijn, Reinout Verfasser], Wolfgang [Akademischer Betreuer] Marquardt, and Martin A. [Akademischer Betreuer] [Grepl. "Empirical model reduction of differential-algebraic equation systems / Reinout Romijn ; Wolfgang Marquardt, Martin Alexander Grepl." Aachen : Universitätsbibliothek der RWTH Aachen, 2016. http://d-nb.info/1130326411/34.
Full text
9
Romijn, Reinout [Verfasser], Wolfgang [Akademischer Betreuer] Marquardt, and Martin A. [Akademischer Betreuer] Grepl. "Empirical model reduction of differential-algebraic equation systems / Reinout Romijn ; Wolfgang Marquardt, Martin Alexander Grepl." Aachen : Universitätsbibliothek der RWTH Aachen, 2016. http://nbn-resolving.de/urn:nbn:de:hbz:82-rwth-2016-001704.
Full text
10
Brown, Robert Winston, and rwb@rmit edu au. "Electrical and Thermal Modelling of Low Power Metallised Polypropylene Capacitors." RMIT University. Electrical and Computer Engineering, 2007. http://adt.lib.rmit.edu.au/adt/public/adt-VIT20080130.155318.
Full textAbstract:
Metallised polypropylene (MPP) capacitors, the dominant capacitor type used in a wide range of power and electronic circuit applications, offer high volumetric capacitor density, low cost, excellent frequency characteristics and a unique ability to recover from point failures in the dielectric film. However MPP capacitors have a generic weakness that is not well understood, failure of the self-healing process leading to ongoing catastrophic failure. The work described in this thesis includes the derivation of an improved electrical model of a capacitor and the uncovering of a mechanism for the catastrophic failure mode. Corrosion of the thin metallic field is firmly linked to drastic increases in metal film current densities and generation of hot spots in capacitors. In the work, novel formulae were derived relating capacitor parameters such as equivalent series resistance and equivalent series capacitance to frequency and physical characteristics such as metal film resistivity and physical dimensions of multiple layer capacitors. Modelling using numerical methods and diffusion equation showed that capacitors with double-end connection topology have more uniform voltage and power distribution than single-end connected capacitors. External characteristics of both connection topologies were shown to be virtually identical up to frequencies well above typical self-resonance. The aggregate spatial distribution of power from both layers and the voltage across the dielectric were found to be fundamentally different in the two circuit connection topologies. In this work it was shown that above singularity frequencies defined by distributed capacitance and metal film spreading resistance, equivalent series resistance and capacitance both fall with the square root of frequency Analysis of the inductance of typical MPP capacitors for single-end and double-end connected topologies and for circumferentially connected capacitor metallization showed that the magnitude and effect of distributed inductance in typical MPP power capacitors was insignificant compared to packaging inductance. Thermal and electrical modelling and experimental measurements showed that corrosion effects could readily account for the generic catastrophic failure mode of metallised polypropylene capacitors. Modelling showed that remnant vestiges of metal bridging corrosion gaps between the schooping and the metallic film could also pose serious thermal danger to the affected capacitor. Fusing current modelling and experimental measurement showed that fusing in metallic films typically occurred for current densities of several hundred thousand amperes per square centimetre. The partial disconnection of the metallic layers from the schooping edge by corrosion for example, was shown to result in large increases in dissipation factor and power loss in a capacitor readily explaining how capacitors
11
Degerli, Mustafa. "Identifying Factors Influencing The Acceptance Of Processes: An Empirical Investigation Using The Structural Equation Modeling Approach." Master's thesis, METU, 2012. http://etd.lib.metu.edu.tr/upload/12614321/index.pdf.
Full textAbstract:
In this research, it was mainly aimed to develop an acceptance model for processes, namely the process acceptance model (PAM). For this purpose, a questionnaire, comprising 3-part and 81-question, was developed to collect quantitative and qualitative data from people having relationships with certain process-focused models and/or standards (CMMI, ISO 15504, ISO 9001, ISO 27001, AQAP-160, AQAP-2110, and/or AS 9100). To revise and refine the questionnaire, expert reviews were ensured, and a pilot study was conducted with 60 usable responses. After reviews, refinements and piloting, the questionnaire was deployed to collect data and in-total 368 usable responses were collected from the people. Here, collected data were screened concerning incorrectly entered data, missing data, outliers and normality, and reliability and validity of the questionnaire were ensured. Partial least squares structural equation modeling (PLS SEM) was applied to develop the PAM. In this context, exploratory and confirmatory factor analyses were applied, and the initial model was estimated and evaluated. The initial model was modified as required by PLS SEM, and confirmatory factor analysis was repeated, and the modified final model was estimated and evaluated. Consequently, the PAM, with 18 factors and their statistically significant relationships, was developed. Furthermore, descriptive statistics and t-tests were applied to discover some interesting, meaningful, and important points to be taken into account regarding the acceptance of processes. Moreover, collected quantitative data were analyzed, and three additional factors were discovered regarding the acceptance of processes. Besides, a checklist to test and/or promote the acceptance of processes was established.
12
Lancaster, Steven L. "AN EMPIRICAL TEST OF A COGNITIVE MODEL OF PTSD USING PATH ANALYSIS AND STRUCTURAL EQUATION MODELING." OpenSIUC, 2011. https://opensiuc.lib.siu.edu/dissertations/388.
Full textAbstract:
This current study empirically tested elements of Ehlers and Clark's (2000) cognitive model of Posttraumatic Stress Disorder (PTSD) symptom maintenance using path analysis and structural equation modeling (SEM). Ehlers and Clark's model suggests that a reciprocal relationship between cognitive appraisals of the traumatic event and characteristics of the trauma memory maintain symptoms by increasing one's sense of current threat. Participants in the current study were 405 undergraduates at a Midwestern university who each reported having experienced at least one traumatic event during his/her lifetime. Path analysis was utilized to examine the possibility that one's posttraumatic cognitions may mediate the relationship between the centrality of the traumatic event to one's sense of self and one's current level of PTSD symptoms. The reverse mediation was also tested for each of the PTSD symptom clusters. Results indicate that both event centrality and posttraumatic cognitions are unique and independent predictors of current symptom level. SEM procedures were used to examine possible mediation as well as to test a reciprocal relationship between these predictors. Results are generally consistent with those from the path analysis although additional research is necessary before any firm conclusions can be stated. Overall, the results of this study support aspects of the cognitive model of PTSD; cognitive appraisals of the self and memory characteristics of the event were highly related to levels of distress. However, the current study suggests that overly integrated trauma memories lead to greater distress and not poorly integrated ones as suggested by Ehlers and Clark. The relationship between trauma memories and PTSD is in need of further study as is the role of memory and cognitions in the temporal development of PTSD.
13
Arner, Wayne. "A DERIVATION OF AN EMPIRICAL EQUATION FOR ESTIMATING THE ACOUSTICAL SHADOW ZONE LENGTH OF ROADWAY NOISE BARRIERS." Master's thesis, University of Central Florida, 2006. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/2329.
Full textAbstract:
The objective of this research was to derive an empirical equation that estimates the acoustical shadow zone length (SZL) of roadway noise barriers. The acoustical shadow zone is the area behind a noise barrier of reduced sound levels, generally to some stated level at or near background. The ability to predict the SZL can be used as a method to evaluate the performance, and possibly the design, of roadway noise barriers. The current federally required roadway noise model is the Federal Highway Administration (FHWA) Traffic Noise Model (TNM). TNM uses insertion loss (IL) to evaluate the effectiveness of a barrier. Insertion loss is the difference in sound level between the "no barrier" and the "with barrier" case. One major limitation with TNM is that the reported IL does not take into account how background noise levels influence the mitigated sound levels. Background noise can be defined as the noise present at a barrier location in the absence of roadway noise. The shadow zone represents a region behind the noise barrier where the barrier is effective at reducing noise levels and takes into account how background noise affects the IL and thus the SZL. The inclusion of background noise becomes significant in evaluating barrier effectiveness because as the distance from the barrier increases, background noise begins to overtake roadway noise as the dominate noise source. The derivation of the empirical equation began by collecting in-situ noise measurements at 18 noise barrier locations across Florida. The measured noise data was supplemented by noise data obtained from computer modeling. After a sufficient quantity of measured and modeled IL data was obtained, a contour of equal IL (IL = 5 dB) was plotted for each barrier location. The area defined by the contour is called the shadow zone. All the SZLs were statistically compared to several variables that were expected to influence it. Regression modeling showed that the background noise level, noise barrier height, the distance from the roadway to the noise barrier, and percent of heavy truck traffic volume were statistically significant as useful predictors of SZL. Two empirical equations were derived, one from linear regression and one from polynomial regression, and are referred to as the Shadow Zone Equations.M.S.Env.E.
Department of Civil and Environmental Engineering
Engineering and Computer Science
Environmental Engineering
14
Wang, Catherine Lihong. "Knowledge management orientation, organisational capabilities and performance : an empirical test of performance relationships using structural equation modeling." Thesis, University of Wolverhampton, 2003. http://hdl.handle.net/2436/96617.
Full text
15
Al-Kazemi, Saad A. "Patenting Activity, Firm Innovation Characteristics, and Financial Performance: An Empirical Investigation." Cleveland, Ohio : Case Western Reserve University, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=case1249013130.
Full textAbstract:
Thesis (Ph.D.)--Case Western Reserve University, 2009Title from PDF (viewed on 19 August 2009) Department of Accounting Includes abstract Includes bibliographical references Available online via the OhioLINK ETD Center
16
Copana, Paucara Julio. "Seismic Slope Stability: A Comparison Study of Empirical Predictive Methods with the Finite Element Method." Thesis, Virginia Tech, 2020. http://hdl.handle.net/10919/100797.
Full textAbstract:
This study evaluates the seismically induced displacements of a slope using the Finite Element Method (FEM) in comparison to the results of twelve empirical predictive approaches. First, the existing methods to analyze the stability of slopes subjected to seismic loads are presented and their capabilities to predict the onset of failure and post-failure behavior are discussed. These methods include the pseudostatic method, the Newmark method, and stress-deformation numerical methods. Whereas the pseudostatic method defines a seismic coefficient for the analysis and provides a safety factor, the Newmark method incorporates a yield coefficient and the actual acceleration time history to estimate permanent displacements. Numerical methods incorporate advanced constitutive models to simulate the coupled stress-strain soil behavior, making the process computationally more costly. In this study, a model slope previously studied at laboratory scale is selected and scaled up to prototype dimensions. Then, the slope is subjected to 88 different input motions, and the seismic displacements obtained from the numerical and empirical approaches are compared statistically. From correlation analyses between seven ground motion parameters and the numerical results, new empirical predictive equations are developed for slope displacements. The results show that overall the FEM displacements are generally in agreement with the numerically developed methods by Fotopoulou and Pitilakis (2015) labelled "Method 2" and "Method 3", and the Newmark-type Makdisi and Seed (1978) and Bray and Travasarou (2007) methods for rigid slopes. Finally, functional forms for seismic slope displacement are proposed as a function of peak ground acceleration (PGA), Arias intensity (Ia), and yield acceleration ratio (Ay/PGA). These functions are expected to be valid for granular slopes such as earth dams, embankments, or landfills built on a rigid base and with low fundamental periods (Ts<0.2).Master of Science
A landslide is a displacement on a sloped ground that can be triggered by earthquake shaking. Several authors have investigated the failure mechanisms that lead to landslide initiation and subsequent mass displacement and proposed methodologies to assess the stability of slopes subjected to seismic loads. The development of these methodologies has to rely on field data that in most of the cases are difficult to obtain because identifying the location of future earthquakes involves too many uncertainties to justify investments in field instrumentation (Kutter, 1995). Nevertheless, the use of scale models and numerical techniques have helped in the investigation of these geotechnical hazards and has led to development of equations that predict seismic displacements as function of different ground motion parameters. In this study, the capabilities and limitations of the most recognized approaches to assess seismic slope stability are reviewed and explained. In addition, a previous shaking-table model is used for reference and scaled up to realistic proportions to calculate its seismic displacement using different methods, including a Finite Element model in the commercial software Plaxis2D. These displacements are compared statistically and used to develop new predictive equations. This study is relevant to understand the capabilities of newer numerical approaches in comparison to classical empirical methods.
17
Kang, In Gu. "Empirical testing of a human performance model| Understanding success in federal agencies using second-order structural equation modeling." Thesis, Indiana University, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=3715873.
Full textAbstract:
Even though various models have been developed in the field of human performance technology (HPT), little research has been done to empirically test these models of human performance (HP) with large amounts of data. This insufficient evidence on whether or not HP models work in practice discourages HPT professionals and workers from applying HP models into their own contexts. This study aims to examine structural relationships among performance support systems (PSS), human behaviors (HB), and performance (PER) in order to test the proposed performance model. Using national government-wide representative data from the 2012 Federal Employee Viewpoint Survey (FEVS, N=687,687, 82 federal agencies), this study has the opportunity to empirically test a comprehensive performance model (Bichelmeyer & Horvitz, 2006) using structural equation modeling (SEM). In measurement model I, a 1st order confirmatory factor analysis (CFA), all model fit indices were found to be adequate (?
2(93) = 90800.207; CFI = .949; TLI = .926; RMSEA = .038; SRMR = .030). All factor loadings of the observed variables were significant (p < .001), indicating that all first-order factors were well measured by the indicators. In measurement model II, a 2nd order CFA, all model fit indices were also found to be in adequate range (?
2(111) = 120515.246; CFI = .933; TLI = .918; RMSEA = .040; SRMR = .036). All factor loadings of the first-order factors used to measure the second-order factors were statistically significant (p < .001), indicating that all the second-order factors were well measured by the first-order factors. In structural model, a 2nd order SEM, all model fit indices demonstrated the proposed model is entirely adequate (?
2(111) = 120515.381; CFI = .933; TLI = .918; RMSEA = .040; SRMR = .036). In terms of structural relationships, results supported the hypothesized direct associations among PSS, HB, and PER. Four steps outlined by Baron and Kenny (1986) and Judd and Kenny (1981) were taken for mediation analysis. In addition, bootstrapping (1,000) with confidence intervals was used for a robust examination of the mediating effect of HB. The results indicated that HB partially mediated the relationship between PSS and PER (?_11* ?_21 = .35, p < .001, 95% CI [0.34 to 0.37]). Finally, implications are discussed based on the results and findings of this study. At the first-order factor level, various sets of practices for Human Performance Technology (HPT), Human Resource Management (HRM), and Human Resource Development (HRD) are presented.
18
Dömeland, Narvaez Dörte. "Empirical studies on human capital and natural resources." Doctoral thesis, Universitat Pompeu Fabra, 2006. http://hdl.handle.net/10803/7345.
Full textAbstract:
El primer capítulo de la tesis sobre "Estudios Empíricos sobre Capital Humano e Instituciones" presenta estimaciones de retornos a la educación en Alemania y analiza los determinantes de las preferencias educativas. El segundo capítulo utiliza estimaciones de retornos a la experiencia en el país de origen de inmigrantes en Estados Unidos para proporcionar evidencia empírica que el comercio aumenta la acumulación de capital humano en el trabajo, incluso en los países menos desarrollados, resolviendo la ambigüedad teórica si el comercio aumenta o disminuye "learning-by-doing". La acumulación de capital humano en el trabajo es también positivamente asociada con el PIB per capita, un alto nivel de educación y una mayor calidad de políticas e instituciones. El último capítulo analiza el efecto de recursos naturales y asistencia externa sobre la calidad de instituciones, proporcionando evidencia empírica que -contrario a la asistencia externa, la abundancia de mineral y combustible tiende a ser asociada negativamente con la calidad de instituciones si la fragmentación étnica es grande.The first chapter of the thesis on "Empirical Studies on Human Capital and Institutions" presents estimates of returns to education in Germany and analyses the determinants of educational choices. The second chapter uses estimated returns to home country experience of US immigrants to provide empirical evidence that trade increases on-the-job human capital accumulation even in less developed countries, thereby resolving the theoretical ambiguity whether trade increases or decreases learning-by-doing. Similar to trade, GDP per capita, a high average level of educational attainment and stronger quality of policy and institutions are found to be positively associated with on-the-job human capital accumulation. The last chapter analyses the effect of natural resources and aid on institutions, providing empirical evidence that contrary to aid, mineral and fuel abundance tends to be associated with significantly lower quality of institutions if ethnic fractionalization is large.
19
Yunus, Erlinda Nusron. "Drivers of Supply Chain Integration and the Role of Organizational Culture: Empirical Evidence from Indonesia." OpenSIUC, 2012. https://opensiuc.lib.siu.edu/dissertations/525.
Full textAbstract:
The increasing emphasis on integration among members of a supply chain has led to new mechanisms to help firms coordinate the flow of products, services, and information through the supply chain. Many studies support the importance and influence of supply chain integration on firm performance but only a few focus on factors driving the integration practices. Moreover, the role of organizational contextual factors that could influence supply chain integration has been largely overlooked. This research examines firms' internal and external drivers of supply chain integration, as well as evaluates the impact of the integration on firm performance. This study further investigates the moderating role of organizational culture, based on the dimensions of control-flexibility orientation and internal-external focus, in strengthening or weakening the relationships between supply chain integration and its antecedents. For the purpose of this study, manufacturing firms were identified as the focal firms in supply chains, and thus data was collected through a survey of 223 Indonesian-based manufacturing firms. Two informants from each firm became the respondents. Structural equation modeling was used to analyze the data, and this study confirmed the positive relationships between supply chain integration and firm performance. The results also indicated that internal driver, or specifically firms' customer orientation, triggered the initiation of supply chain integration. Other factors, such as demand uncertainty, supply uncertainty, technology uncertainty, as well as firms' anticipation of benefits, were not significantly related to the degree of supply chain integration. Furthermore, focal firms with external focus were pursuing a higher degree of supply chain integration than those with internal focus. By investigating the linkages between internal and external drivers, supply chain integration, firm performance, and organizational culture, this study attempts to contribute to the Operations Management discipline, especially to the area of supply chain management. Implications for research and practice are discussed.
20
Tuttle, Matthew D. "True North or Traveled Terrain? An Empirical Investigation of Authentic Leadership." [Tampa, Fla] : University of South Florida, 2009. http://purl.fcla.edu/usf/dc/et/SFE0003188.
Full text
21
Cakir, Murat. "Development And Validation Of B2c E-commerce Adoption Model: An Empirical Investigation Using Structural Equation Modeling And Interpretative Phenomenological Analyses." Phd thesis, METU, 2012. http://etd.lib.metu.edu.tr/upload/12614895/index.pdf.
Full textAbstract:
Incentive for this research stems from the fact that Business-to-Consumer electronic commerce sector is going to oligopoly and the new actors have relatively less chance to accomplish in the current market if they follow the same ways that the old companies have already paved. Considering this challenge, the aim is to understand the adoption process of customers by analyzing the contemporary perceptions of individuals against e-shopping. Initially, business-to-consumer electronic commerce adoption model is developed. Proposed model and hypotheses are tested with Partial Least Squares as a Structural Equation Modeling technique using data collected from 1115 respondents via an online survey. Then, semi-structured open-ended interviews are conducted in order to grasp the perceptions of customers. The results are interpreted following a systematic mixed methodology involving Interpretative Phenomenological Analysis to elucidate the antecedents and causal relations of constructs in an inductive and exploratory way to illuminate a socio-technical phenomenon as complementary to deductive and confirmatory quantitative perspective. Findings and implications are asserted to be utilized as a roadmap especially for start-up companies that challenge to survive and succeed in current market conditions. Trust is found to be the predominant factor in e-shopping adoption. It is proved that, after almost two decades shopping via Internet had been invented, contemporarily, definitions for the dimensions of Enjoyment, Perceived Usefulness, Store Familiarity, Perceived Ease of Use and Subjective Norm have
evolved into new semantics and customers perceive each factor according to their actual cognition contexts.
22
Bouadoumou, Maxime K. "Jackknife Empirical Likelihood for the Accelerated Failure Time Model with Censored Data." Digital Archive @ GSU, 2011. http://digitalarchive.gsu.edu/math_theses/112.
Full textAbstract:
Kendall and Gehan estimating functions are used to estimate the regression parameter in accelerated failure time (AFT) model with censored observations. The accelerated failure time model is the preferred survival analysis method because it maintains a consistent association between the covariate and the survival time. The jackknife empirical likelihood method is used because it overcomes computation difficulty by circumventing the construction of the nonlinear constraint. Jackknife empirical likelihood turns the statistic of interest into a sample mean based on jackknife pseudo-values. U-statistic approach is used to construct the confidence intervals for the regression parameter. We conduct a simulation study to compare the Wald-type procedure, the empirical likelihood, and the jackknife empirical likelihood in terms of coverage probability and average length of confidence intervals. Jackknife empirical likelihood method has a better performance and overcomes the under-coverage problem of the Wald-type method. A real data is also used to illustrate the proposed methods.
23
Van, Deventer Megan. "The development and empirical evaluation of an work engagement structural model." Thesis, Stellenbosch : Stellenbosch University, 2015. http://hdl.handle.net/10019.1/96784.
Full textAbstract:
Thesis (MComm)--Stellenbosch University, 2015.ENGLISH ABSTRACT: Work Engagement is one construct of many that forms part of the complex nomological network of constructs underlying the behaviour of working man2. Work Engagement is an important construct both from an individual as well as from an organisational perspective. Human resource management interventions aimed at enhancing Work Engagement aspire to contribute to the achievement of the organisation’s primary objective and the well-being of the organisation’s employees. Such interventions will most likely also be valued by individuals within the workplace, as individuals will be able to experience a sense of personal fulfilment through self-expression at work. It is therefore essential to gain a valid understanding of the Work Engagement construct and the psychological mechanism that underpins it, in order to design human resource interventions that will successfully enhance Work Engagement. The current study raises the question why variance in Work Engagement exists amongst different employees working in different organisational contexts. The research objective of the current study is to develop and empirically test an explanatory Work Engagement structural model that will provide a valid answer to this question. In this study, a comprehensive Work Engagement structural model was proposed. An ex post facto correlational design with structural equation modelling (SEM) as the statistical analysis technique was used to test the substantive research hypotheses as represented by the Work Engagement structural model. Furthermore, the current study tested two additional narrow-focus structural models describing the impact of value congruence on Work Engagement by using an ex post facto correlational design with polynomial regression as the statistical analysis technique. A convenience sample of 227 teachers working in public sector schools falling under the jurisdiction of the Western Cape Education Department (WCED) participated in the study. The comprehensive Work Engagement model achieved reasonable close fit. Support was found for all of the hypothesised theoretical relationships in the Work Engagement structural model, except for the influence of the PsyCap*Job Characteristics interaction effect on Meaningfulness and for three of the five latent polynomial regression terms added in the model in an attempt to derive response surface test values. The response surface analyses findings were mixed. Based on the obtained results, meaningful practical recommendations were derived.
AFRIKAANSE OPSOMMING: Werkverbintenis1 is een van ‘n groot verskeidenheid konstrukte wat deel vorm van die komplekse nomologiese netwerk van konstrukte wat die gedrag van die arbeidende mens onderlê. Werkverbintenis word as ‘n belangrike konstruk beskou vanuit ‘n individuele sowel as vanuit ‘n organisatoriese perspektief. Menslike hulpbronbestuurs-intervensies gerig op die bevordering van Werkverbintenis streef daarna om by te dra tot die bereiking van die organisasie se primêre doel sowel as tot die welstand van die organisasie se werknemers. Sodanige intervensies sal waarskynlik ook deur werknemers waardeer word, aangesien sodanige intervensies die kanse verhoog dat individue selfvervulling in hul werk sal ervaar omdat die werk hul die geleentheid bied om hulself in hul werk uit te leef. Dit is gevolglik noodsaaklik om ‘n geldige begrip te ontwikkel van die Werkverbintenis-konstruk en die sielkundige meganisme wat dit onderlê ten einde menslike hulpronbestuurs-intervensies te ontwerp wat suksesvol Werkverbintenis sal bevorder. Die huidige studie stel die vraag aan die orde waarom variansie in Werkverbintenis tussen verskillende werknemers bestaan wat in verskillende organisatoriese kontekste werk. Die navorsingsdoelstelling van die huidige studie is om ‘n verklarende Werkverbintenisstrukturele model te ontwikkel en te toets wat ‘n geldige antwoord op hierdie vraag sal bied. ‘n Omvattende Werkverbintenis strukturele model is in hierdie studie voorgestel. ‘n Ex post facto korrelatiewe ontwerp met strukturele vergelykingsmodellering (SVM) as die statistiese ontledingstegniek is gebruik om die substantiewe navorsingshipotese soos voorgestel deur die Werkverbintenis strukturele model te toets. Die huidige studie het voorts twee addisionele nouer-fokus strukturele modelle getoets wat die impak van waardekongruensie op Werkverbintenis beskryf deur middel van ‘n ex post facto korrelatiewe ontwerp met polinomiese regressie-ontleding as statistiese ontledingstegniek. ‘n Geriefsteekproef van 227 onderwysers wat in openbare skole werksaam is wat onder die beheer van die Wes Kaapse Department van Onderwys val (WKDO) het aan die studie deelgeneem. Die omvattende Werkverbintenis-model het redelik goeie pasgehalte getoon. Steun is gevind vir all die voorgestelde teoretiese verwantskappe in die Werkverbintenis strukturele model, behalwe vir die invloed van die Sielkundige kapitaal*Werk eienskappe-interaksie-effek op Betekenisvolheid en vir drie van die vyf polinomiese latente regressie-terme wat in die model ingesluit is in ‘n poging om responsoppervlakte-waardes af te lei. Gemengde resultate is verkry vir die responsoppervlakte-ontleding. Betekenisvolle praktiese aanbevelings is gemaak op grond van die navorsingsresultate.
24
Kwock, Yongsub. "A Theoretical Integration and Empirical Test of Strategic Management: Environment, Strategy, Structure, Implementation, and Performance in the Hospitality Industry." Diss., Virginia Tech, 1999. http://hdl.handle.net/10919/37653.
Full textAbstract:
The main purposes of this study were to investigate the causality, congruence, and relationships among the constructs in the strategic management process. Perceived environmental certainty, organizational structure, types of strategy, types of strategy implementation, and satisfaction level with performance were selected as relevant constructs for this study.
A total of 184 responses to a survey given to top management in the hospitality industry, including restaurant and lodging firms, were analyzed. The various relationships among the constructs were hypothesized and tested by utilizing exploratory factor, confirmatory factor, and structural equation modeling analyses. The exploratory factor analysis revealed several dimensions of both strategy and strategy implementation constructs. The reliabilities, validities, and model fits of each construct and of all constructs together were assessed by utilizing confirmatory factor analysis. Finally, the various structural relationships among the constructs were tested by structural equation modeling.
Results revealed the existence of causality in the model. Results also indicated a positive relationship between perceived environmental certainty and the defender type of strategy. A negative effect of the defender type of strategy and a positive effect of the prospector type of strategy on organic organizational structure were revealed. Perceived environmental certainty had a positive effect on the collaborator type of strategy implementation. An organic organizational structure had a positive effect on the commander type of strategy implementation. A positive effect of the defender type of strategy on the commander type of strategy implementation, and the positive effect of the prospector type of strategy on the collaborator type of strategy implementation were identified. There were positive effects of the prospector type of strategy and the collaborator type of strategy implementation on the satisfaction level with performance. Finally, a positive effect of the congruence between the prospector type of strategy and the collaborator type of strategy implementation on the satisfaction level with performance was revealed.
Several hypothesized relationships were not supported: a negative effect of perceived environmental certainty on the prospector type of strategy, a negative effect of perceived environmental certainty on organic organizational structure, a positive effect of perceived environmental certainty on the commander type of strategy implementation, a positive effect of an organic organizational structure on the collaborator type of strategy implementation, a positive effect of the defender type of strategy on the satisfaction level with performance, and a positive effect of the commander type of strategy implementation on the satisfaction level with performance.
The results of statistical analysis implied that top management in the hospitality industry did not perceive the environment as an important factor contributing to a firmâ s performance. In addition, top management was reluctant to change organizational structure. Also, many firms in the industry still practice a defensive strategy and strategy implementation with the traditional pyramid type of organizational structure, which does not contribute positively to a satisfaction level with performance. Finally, the prospector type of strategy and the collaborator type of strategy implementation were important contributors to the satisfaction level with performance.
In spite of some limitations, including the problems associated with generalizability, the advantages that could have been gained by a longitudinal study, the lack of some relevant variables, and subjective nature of the data, the findings of this study contribute to a better understanding of the strategic management process in the hospitality industry by revealing various relationships among the constructs in the strategic management process.Ph. D.
25
Kanat, Irfan Emrah. "E-government Adoption Model Based On Theory Of Planned Behavior: Empirical Investigation." Master's thesis, METU, 2009. http://etd.lib.metu.edu.tr/upload/12610714/index.pdf.
Full textAbstract:
The e-government phenomena has become more important with the ever increasing number of implementations world wide. A model explaining the e-government adoption and the related measurement instrument a survey had been developed and validated in this study. In a post technology acceptance model (TAM) approach, theory of planned behavior (TPB) was extended to t the requirements of e-government context. The
adoption of student loans service of the higher education student loans and accommodation association (KYK) was investigated to obtain data for empirical validation. The
instrument was administered to over four-hundred students and partial least squares path modeling was employed to analyze the data. The results indicate that the model was an improvement over TAM in terms of predictive power. The constructs investigated in the study successfully explained the intention to use an e-government service.
26
Blekh, Aleksandr. "Governance and organizational sponsorship as success factors in free/libre and open source software development: An empirical investigation using structural equation modeling." NSUWorks, 2015. http://nsuworks.nova.edu/gscis_etd/40.
Full textAbstract:
Recent advances in information technologies and subsequent explosive growth of computer software use in practically all aspects of everyday life provide tremendous opportunities and benefits for improving people's lives. However, significant proportion of software projects represents cancelled, abandoned or otherwise failed projects. This situation exists not only in commercial software products or government information systems, but also in an increasingly popular and important domain of free/libre and open source software (FLOSS).
The problem of failures in software development projects requires identification and understanding of the factors of success and their interrelationships. Practice and previous research suggest that governance of software development projects plays crucial role in their success. Increasing adoption and sponsorship of FLOSS by commercial firms and government organizations present additional challenges; such sponsorship may also interact with governance in FLOSS projects and play a role in determining their success.
This dissertation focused on analyzing the role and significance of governance and organizational sponsorship in the success of FLOSS development. This study used both conceptual analysis and empirical methods. The conceptual analysis phase, a preliminary study based on the review of existing literature, produced a partial model of success in FLOSS development. This model was verified in an empirical phase, which statistically analyzed data from multiple FLOSS repositories and other public sources. The statistical analysis was based on structural equation modeling (SEM) approach.
Results of this study did not confirm hypothesized effects of the main two factors (governance and organizational sponsorship) on FLOSS success, but confirmed a positive effect of project maturity on the success. The likely reason of the lack of support for the main factors is unavailability of sufficient and correct data for proper operationalization. This and other uncovered issues are planned to be addressed in the future research on the topic, for which this dissertation formed a solid conceptual and data analysis framework.
27
Chen, Chun-I. Philip. "Factors Affecting Business-to-Business Electronic Commerce Success: An Empirical Investigation." NSUWorks, 2010. http://nsuworks.nova.edu/gscis_etd/118.
Full textAbstract:
It is generally believed that Business to Business (B2B) e-commerce has a great impact on business performance improvement. Considerable research also shows that another dependent variable, B2B e-commerce success, can be a good overall measure of B2B systems. This paper investigated and examined the impact of several factors, which are either internal or external to the firm on B2B performance improvement and B2B e-commerce success. It is suggested that the various factors affect B2B success through business performance improvement.
A research model was developed to test and evaluate these factors. A survey instrument was developed to examine the relationships between these factors and business performance. Survey data was collected online from 143 companies in the U.S.A. and Taiwan where their B2B e-commerce systems were operational for more than 1 year. Structural Equation Modeling (SEM) technique was used to assess the measurement and the structural model.
Analyses and results of the pooled survey data suggest that the following factors are significant in the B2B e-commerce environments: (a) alignment of business and e-commerce strategy has a positive impact on business performance, (b) strong relationships between the trading partners have a positive influence on business performance, and (c) B2B e-commerce success is significantly influenced by business performance improvements. Thus, firms that seek to implement successful B2B systems should focus on business performance improvements.
28
Teker, Mahmut. "Identifying Factors That Facilitate The Use Of Multi-purpose Smart Cards By University Students: An Empirical Investigation." Master's thesis, METU, 2011. http://etd.lib.metu.edu.tr/upload/12612983/index.pdf.
Full textAbstract:
The aim of this thesis is to identify factors that affect the university students&rsquoacceptance of multi-purpose Smart Cards. The findings of this study will be beneficial to facilitate the use of Smart-Card enabled system both n universities and in other institutions which either have these systems in use or plan to invest on these systems in the future. The research methodology employed within this study is based on quantitative methods. A survey instrument comprising 51 5-point Likert-type questions has been developed and applied to 207 university Middle East Technical University students. The data collected has been analyzed using Exploratory Factor Analysis to categorize factors having items. According to analysis results, the data classified under 5 factors
Perceived Usefulness, Perceived Ease of Use, Behavioral Intention, Anxiety, and Technological Complexity. Then, the relations between these 5 factors identified and a measurement model was created. For assessing the proposed model Discriminant and Convergent Validity scores were calculated by Confirmatory Factor Analysis. Then, Structural Equation Modeling was conducted with Partial Least Squares for validating the model&rsquo
s estimated influence. The study has shown that the main Technology Acceptance Model constructs fit for determining the university students&rsquo
intention of Smart Card usage except for Perceived Ease of Use over Behavioral Intention. Moreover, study showed that Anxiety and Technological Complexity were the external factors that have effect on willingness of using multi-purpose Smart Cards. If students have Anxiety, this affects their perception of easiness of the system and it has negative indirect effect on the perceived usefulness and direct effect on intention. Technological Complexity is another factor which has direct affect on the perception of easiness and usefulness and intention.
29
Dawson, Matthew D. "AN EMPIRICAL TEST OF A MODEL OF THE IMPACT OF ATTACHMENT STYLE ON DEPRESSIVE SYMPTOMS, CONFLICT RESOLUTION, AND MARITAL QUALITY." The Ohio State University, 2002. http://rave.ohiolink.edu/etdc/view?acc_num=osu1038947437.
Full text
30
Rudolph, Michael J. "DO INTERCOLLEGIATE ATHLETICS SUBSIDIES CORRELATE WITH EDUCATIONAL SPENDING? AN EMPIRICAL STUDY OF PUBLIC DIVISION-I COLLEGES AND UNIVERSITIES." UKnowledge, 2017. http://uknowledge.uky.edu/epe_etds/51.
Full textAbstract:
Intercollegiate athletics are a prominent feature of American higher education. They have been characterized as the “front door” to the university due to their unique ability to draw alumni and other supporters to campus. It is often supposed that the exposure from high-profile athletics produces a number of indirect benefits including greater institutional prestige. Such exposure comes at a cost, however, as most Division I athletics programs are not financially self-sufficient and receive institutional subsidies to balance their budgets. At present, it is unclear how institutions budget for athletics subsidies or whether the recent increases in subsidies have impacted the overall financial picture of colleges and universities. Prior research has shown that athletics subsidies and student tuition and fees are not significantly correlated for public Division I institutions, which suggests the possibility that institutions have reallocated funds from other core areas to athletics. In this dissertation, the relationship between athletics subsidies and one of the most important core areas of the university – education and related activities – was examined. This relationship was investigated using fixed-effects structural equation models to analyze a panel dataset of public Division I institutions.
It was found that total athletics subsidies (school funds and student fees) per student and education and related spending per student were positively correlated. This suggests that rather than decrease educational spending, institutions that increase total athletics subsidies have simultaneously increased their educational expenditures. However, in the analyses involving the more restrictive definition of athletics subsidies, it was shown that athletics subsidies from school funds was not correlated with educational spending. The results also provided some evidence that differences in the relationship between athletics subsidies and educational spending exist according to Carnegie classification and level of athletics competition. The findings from this study have a number of implications for higher education policy and future research. The absence of a negative relationship between athletics subsidies and educational spending suggests that athletics subsidies are not associated with decreases in educational spending that could ultimately harm the quality of education provided by colleges and universities. Furthermore, the existence of a positive correlation between athletics subsidies and educational spending and the fact that core revenues were controlled for in the models suggest the possibility that institutions have redirected funds from other areas to support education and athletics.
31
Muhammed, Shahnawaz. "Antecedents and Impacts of Knowledge Management Practices Supported by Information Technology: An Empirical Study in Manufacturing Context." University of Toledo / OhioLINK, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1153916152.
Full text
32
Schmitz-Justen, Felix J. [Verfasser]. "Forum-based online knowledge communities : knowledge processes and their factors of influence [[Elektronische Ressource]] : an empirical study using structural equation modeling / Felix J. Schmitz-Justen." Bremen : IRC-Library, Information Resource Center der Jacobs University Bremen, 2008. http://d-nb.info/1034767895/34.
Full text
33
Schmitz-Justen, Felix [Verfasser]. "Forum-based online knowledge communities : knowledge processes and their factors of influence [[Elektronische Ressource]] : an empirical study using structural equation modeling / Felix J. Schmitz-Justen." Bremen : IRC-Library, Information Resource Center der Jacobs University Bremen, 2008. http://nbn-resolving.de/urn:nbn:de:101:1-201305171065.
Full text
34
Alomiri, Hamdi. "The impact of leadership style and organisational culture on the implementation of e-services : an empirical study in Saudi Arabia." Thesis, University of Plymouth, 2016. http://hdl.handle.net/10026.1/4343.
Full textAbstract:
There is a general scarcity of empirical studies investigating the impact of leadership styles on e-Government use in the service industry. This is doubly true of styles such as transformational, transactional and servant leadership. Theorised models propose that leadership style forms the desired organisational culture for implementing e-services, organisational culture being the mediator and the national culture the moderator. This research fills the empirical gap by investigating how leadership forms the organisational culture that facilitates and enhances the implementation and use of e-government in organisations in Saudi Arabia. The research was conducted through the sampling of employees in private and public sectors. While the data for the leadership styles, organisational culture and national culture were collected through the use of questionnaires designed for employees, the e-services were measured through organizations’ official websites. All data were processed and analysed using computer software (WarPPLS) and SPSS. The results support the hypothesized relationships proposed in the theoretical model, wherein all constructs under study (except for the mediating effect of National Culture (NC) on the relationship between leadership styles and organisational culture) positively affect e-services implementation, including Individualized Influence (IINF), Intellectual Stimulation (ISTIM), Individualized Support (ISUP), Contingent Reward (CR), Management by Exception (MbE), Servant Leadership (SL), Bureaucratic Culture (BC), Involvement Culture (INVC), Mission Culture (MC), Innovative Culture (INC), Task Culture (TC) and Future Culture (FC) and the mediating effect of National Culture (NC) on the relationship between organisational culture and e-services implementation. The results also indicated that specific leadership styles have direct and positive impacts on e-services implementation and indirect influences through a mediating organisational culture and a moderating national culture. The empirical findings bring new evidence in support of this proposal, indicating that specific leadership styles play crucial roles in influencing processes and outcomes within organizations. According to these results, e-services differ from one organization to another, and these variations were correlated to leadership styles and organizational culture. It was found that there were positive and significant correlations between total leadership styles (hybrid) and total organizational cultures (hybrid) in the full sample and in e-services implementation. E-services implementation increases when the mean for leadership styles rises, but types of organizational culture were also crucial factors in achieving better e-services. The national culture variable, which was used as a moderator, did not have a significant influence on the relationship between leadership style and organisational culture. Therefore, the moderating role of national culture in the relationship between leadership styles and organisational culture did not have any level of statistical significance, which means that regardless of the national culture (power distance or uncertainty avoidance) the effect of leadership style on organisational culture in the model adopted in this study appeared to be quite consistent. The study links theory to practice by explaining the subject of modern leadership styles and shows their relevance to the Saudi organisations and business environment. As such, it opens up a domain for investigating the application of modern management theories in a different culture. Although a plethora of studies have investigated the effect of factors such as organisational culture and/or national culture on e-services implementation in Saudi’s organisations, no study (to the best of this writer's knowledge) has tackled the issue of e-services implementation and leadership styles in those organisations. Therefore, studying e-services implementation and leadership styles in Saudi’s organisations is a contribution to the literature on the service industry, adding to its knowledge with a case study from a different cultural setting. The study also opens up a horizon for future research on developing the business sector, as it uses standardized tools in terms of reliability and validity within the context of the e-services implementation. Therefore, this study contributes to existing knowledge in that leadership and organisational culture are revealed to be key contributors to e-services implementation. The three leadership styles - transformational, transactional, and servant leadership - were empirically found to be appropriate styles that work well in e-services implementation projects. These styles have direct and positive benefits to e-services implementation and an indirect impact through the mediating means of organisational culture, and empirical findings bring new evidence for this notion. Moreover, the six organisational cultural dimensions were judged to be appropriate supporters of e-services implementation, specifically: involvement, mission, innovation, task-orientation, bureaucracy, and future-orientation.
35
Kamilis, Dimitrios. "Uncertainty Quantification for low-frequency Maxwell equations with stochastic conductivity models." Thesis, University of Edinburgh, 2018. http://hdl.handle.net/1842/31415.
Full textAbstract:
Uncertainty Quantification (UQ) has been an active area of research in recent years with a wide range of applications in data and imaging sciences. In many problems, the source of uncertainty stems from an unknown parameter in the model. In physical and engineering systems for example, the parameters of the partial differential equation (PDE) that model the observed data may be unknown or incompletely specified. In such cases, one may use a probabilistic description based on prior information and formulate a forward UQ problem of characterising the uncertainty in the PDE solution and observations in response to that in the parameters. Conversely, inverse UQ encompasses the statistical estimation of the unknown parameters from the available observations, which can be cast as a Bayesian inverse problem. The contributions of the thesis focus on examining the aforementioned forward and inverse UQ problems for the low-frequency, time-harmonic Maxwell equations, where the model uncertainty emanates from the lack of knowledge of the material conductivity parameter. The motivation comes from the Controlled-Source Electromagnetic Method (CSEM) that aims to detect and image hydrocarbon reservoirs by using electromagnetic field (EM) measurements to obtain information about the conductivity profile of the sub-seabed. Traditionally, algorithms for deterministic models have been employed to solve the inverse problem in CSEM by optimisation and regularisation methods, which aside from the image reconstruction provide no quantitative information on the credibility of its features. This work employs instead stochastic models where the conductivity is represented as a lognormal random field, with the objective of providing a more informative characterisation of the model observables and the unknown parameters. The variational formulation of these stochastic models is analysed and proved to be well-posed under suitable assumptions. For computational purposes the stochastic formulation is recast as a deterministic, parametric problem with distributed uncertainty, which leads to an infinite-dimensional integration problem with respect to the prior and posterior measure. One of the main challenges is thus the approximation of these integrals, with the standard choice being some variant of the Monte-Carlo (MC) method. However, such methods typically fail to take advantage of the intrinsic properties of the model and suffer from unsatisfactory convergence rates. Based on recently developed theory on high-dimensional approximation, this thesis advocates the use of Sparse Quadrature (SQ) to tackle the integration problem. For the models considered here and under certain assumptions, we prove that for forward UQ, Sparse Quadrature can attain dimension-independent convergence rates that out-perform MC. Typical CSEM models are large-scale and thus additional effort is made in this work to reduce the cost of obtaining forward solutions for each sampling parameter by utilising the weighted Reduced Basis method (RB) and the Empirical Interpolation Method (EIM). The proposed variant of a combined SQ-EIM-RB algorithm is based on an adaptive selection of training sets and a primal-dual, goal-oriented formulation for the EIM-RB approximation. Numerical examples show that the suggested computational framework can alleviate the computational costs associated with forward UQ for the pertinent large-scale models, thus providing a viable methodology for practical applications.
36
Omoge, Akinyemi Paul. "The direct and mediated effects of customer relationship management (CRM) systems usage as service delivery channels on consumer buying behaviour : an empirical appraisal of the context of the Nigerian banking industry." Thesis, Robert Gordon University, 2016. http://hdl.handle.net/10059/2139.
Full textAbstract:
Ample evidence from the literature suggests that in recent years, banks have been heavily investing in customer relationship management (CRM) systems. The reasons for this are traced to banks' emergent need to gain and sustain competitive advantage through greater knowledge of their customers. In turn, this increased knowledge is likely to also lead to increased: a) customer base, b) customer satisfaction, c) customer retention and, d) customer loyalty. The literature suggests that there is a knowledge gap, which relates to the reasons for CRM systems in adoption and usage as service delivery channels, as well as its effects on banks' customers. This is particularly the case with regards to the banks' customers' buying behaviour and is stemming from the fact that bank customers display some unique buying patterns. Based on the above, the aim of this study is to find out whether or not there is a potential influence of newly implemented CRM systems on consumer buying behaviour in the context of the Nigerian banking industry and also to assess the extent and nature of this influence (if any).
37
Kim, Seehyung. "A Causal Model of Linkages between Environment and Organizational Structure, and Its Performance Implications in International Service Distribution: An Empirical Study of Restaurant and Hotel Industry." Diss., Virginia Tech, 2005. http://hdl.handle.net/10919/27373.
Full textAbstract:
This research develops and tests a model of the service unit ownership and control patterns used by international service companies. The main purpose of this study is to investigate trivariate causal relationships among environmental factors, organizational structure, and perceived performance in the internationalization process of service firms. A service firm operating in foreign soil has a choice of three general entry mode strategies offering different degrees of ownership and control of its remote operating units located in foreign countries -- full ownership arrangement, joint venture arrangement, and franchising arrangement.
The entry mode strategies chosen depend on the factors relating to internal environment of a specific firm, industry related factors in which the firm operates, and external environment of the operating units at national context. This study identifies these factors, investigates how they affect the firm's choice of entry modes, and finally examines the impact of entry mode on firm's performance. The overall model has been explained by contingency theory that conceptualizes optimal level of ownership and control mode as a response by the firm to the interplay of environmental factors and as a determinant of firm's performance. To this core can be added complementary theories which are borrowed from agency theory, transaction cost theory, and resource dependence theory. These theories explain the linkages between market entry mode and each type of environmental factors.
In order to empirically test the hypotheses, data were collected from hospitality firms regarding the ownership structure of subsidiaries located in foreign countries. As a whole, the conceptual model developed in the study received strong support from the empirical study. This study found a positive impact of contingency fit on performance and so support contingency theory in which some combinations of the environmental dimensions and organizational structure will lead to better organizational performance. Another finding of this study indicates that the increased level of ownership and control will result in enhancing the level of perceived performance. It should be noted that contingency model-based mode choice would provide managers with the optimal performance because there is not one best performing mode choice in volatile international market.
Next, the relationship of market environment with organizational structure was examined through three different perspectives. Market environment was investigated at firm, industry, and national context, which includes five factors -- monitoring uncertainty, asset specificity, cultural distance, political uncertainty, and economic uncertainty. The model is suggestive of a picture in which five environmental factors vie for affecting the choice of market entry modes. All five environmental factors were found to be significantly related to firms' organizational structure. Among five environmental factors, cultural uncertainty has the largest effect on the choice of entry mode followed by monitoring uncertainty, political uncertainty, asset specificity, and economic uncertainty.
One of the important implications of this research is the inclusion of franchising as an actual management strategy and competitive business practice that is related to international ownership and control strategy. Higher degrees of uncertainty associated with the foreign market encourage external dependence of the venture, in which the operation depends more heavily on local relationships. Franchising substitutes the loss of ownership by an increase of external relationships and it takes without losing control on retail operation. Resource exploitation depends on the local market for either inputs or outputs for better performance. Understanding the fit between the each set of contingent variables and the elements of ownership and control strategy will allow marketers to determine when franchising is the suitable mode of operation in global markets.
Collectively, these results suggest that the choice of an organizational form for international service firms involves a complex balance of firm, industry, and country level factors. Managers can maximize performance by aligning entry mode strategy with external contextual circumstances as well as internal resources. Managers may also be able to make better mode choice decisions using the theory-driven criteria examined in this study, increasing their chances for financial and non-financial success.Ph. D.
38
Simpson, Joseph P. "Empirical Analysis of Socio-Cognitive Factors Affecting Security Behaviors and Practices of Smartphone Users." NSUWorks, 2016. http://nsuworks.nova.edu/gscis_etd/951.
Full textAbstract:
The overall security posture of information systems (IS) depends on the behaviors of the IS users. Several studies have shown that users are the greatest vulnerability to IS security. The proliferation of smartphones is introducing an entirely new set of risks, threats, and vulnerabilities. Smartphone devices amplify this data exposure problem by enabling instantaneous transmission and storage of personally identifiable information (PII) by smartphone users, which is becoming a major security risk. Moreover, companies are also capitalizing on the availability and powerful computing capabilities of these smartphone devices and developing a bring-your-own-device (BYOD) program, which makes companies susceptible to divulgence of organizational proprietary information and sensitive customer information. In addition to users being the greatest risk to IS security, several studies have shown that many people do not implement even the most basic security countermeasures on their smartphones. The lack of security countermeasures implementation, risky user behavior, and the amount of sensitive information stored and transmitted on smartphones is becoming an ever-increasing problem.
A literature review revealed a significant gap in literature pertaining to smartphone security. This study identified six socio-cognitive factors from the domain of traditional computer security which have shown to have an impact on user security behaviors and practices. The six factors this study identified and analyzed are mobile information security self-efficacy, institutional trust, party trust, and awareness of smartphone risks, threats, and vulnerabilities and their influence on smartphone security practices and behaviors. The analysis done in this research was confirmatory factor analysis (CFA) – structural equation modeling (SEM). The goal of this study was to cross-validate previously validated factors within the context of traditional computer security and assess their applicability in the context of smartphone security. Additionally, this study assessed the influential significance of these factors on the security behaviors and practices of smartphone users.
This study used a Web-based survey and was distributed to approximately 539 users through Facebook® and LinkedIn® social media outlets which resulted in 275 responses for a 51% response rate. After pre-analysis data screening was completed, there were a total of 19 responses that had to be eliminated due to unengaged responses and outliers leaving 256 responses left to analyze. The results of the analysis found that vulnerability awareness, threat awareness, and risk awareness are interrelated to one another which all in turn had significance in predicting self-efficacy, security practices, and behaviors. This intricate relationship revealed in this study indicates that a user has to have an increased awareness in all three categories of awareness before they can fully understand how to protect themselves. Having an increased awareness in one category does not impact the overall security posture of the user and that risk, threat, and vulnerability awareness all work together. Another interesting find was that as risk awareness increased the less the smartphone users protected themselves. This finding warrants additional research to investigate why the user is more averse to risk, and willing to accept the risk, despite their increased awareness. Finally, institutional trust and party trust was found not to have any significance on any of the factors.
These findings should give smartphone users and organizations insight into specific areas to focus on in minimizing inappropriate security behaviors and practices of smartphone users. More specifically, users and organizations need to focus on educating users on all three factors of threats, risks, and vulnerabilities in order for there to have any impact on increasing self-efficacy and reducing inappropriate security behaviors and practices.
39
Gericke, Andreas. "Evaluation of empirical approaches to estimate the variability of erosive inputs in river catchments." Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät II, 2013. http://dx.doi.org/10.18452/16861.
Full textAbstract:
Die Dissertation erforscht die Unsicherheit, Sensitivität und Grenzen großskaliger Erosionsmodelle. Die Modellierung basiert auf der allgemeinen Bodenabtragsgleichung (ABAG), Sedimenteintragsverhältnissen (SDR) und europäischen Daten. Für mehrere Regionen Europas wird die Bedeutung der Unsicherheit topographischer Modellparameter, ABAG-Faktoren und kritischer Schwebstofffrachten für die Anwendbarkeit empirischer Modelle zur Beschreibung von Sedimentfrachten und SDR von Flusseinzugsgebieten untersucht. Der Vergleich alternativer Modellparameter sowie Kalibrierungs- und Validierungsdaten zeigt, dass schon grundlegende Modellentscheidungen mit großen Unsicherheiten behaftet sind. Zur Vermeidung falscher Modellvorhersagen sind kalibrierte Modelle genau zu dokumentieren. Auch wenn die geschickte Wahl nicht-topographischer Algorithmen die Modellgüte regionaler Anwendungen verbessern kann, so gibt es nicht die generell beste Lösung. Die Ergebnisse zeigen auch, dass SDR-Modelle stets mit Sedimentfrachten und SDR kalibriert und evaluiert werden sollten. Mit diesem Ansatz werden eine neue europäische Bodenabtragskarte und ein verbessertes SDR-Modell für Einzugsgebiete nördlich der Alpen und in Südosteuropa abgeleitet. In anderen Regionen Europas ist das SDR-Modell bedingt nutzbar. Die Studien zur jährlichen Variabilität der Bodenerosion zeigen, dass jahreszeitlich gewichtete Niederschlagsdaten geeigneter als ungewichtete sind. Trotz zufriedenstellender Modellergebnisse überwinden weder sorgfältige Algorithmenwahl noch Modellverbesserungen die Grenzen europaweiter SDR-Modelle. Diese bestehen aus der Diskrepanz zwischen modellierten Bodenabtrags- und maßgeblich zur beobachteten bzw. kritischen Sedimentfracht beitragenden Prozessen sowie der außergewöhnlich hohen Sedimentmobilisierung durch Hochwässer. Die Integration von nicht von der ABAG beschriebenen Prozessen und von Starkregentagen sowie die Disaggregation kritischer Frachten sollte daher weiter erforscht werden.This dissertation thesis addresses the uncertainty, sensitivity and limitations of large-scale erosion models. The modelling framework consists of the universal soil loss equation (USLE), sediment delivery ratios (SDR) and European data. For several European regions, the relevance of the uncertainty in topographic model parameters, USLE factors and critical yields of suspended solids for the applicability of empirical models to predict sediment yields and SDR of river catchments is systematically evaluated. The comparison of alternative model parameters as well as calibration and validation data shows that even basic modelling decisions are associated with great uncertainties. Consequently, calibrated models have to be well-documented to avoid misapplication. Although careful choices of non-topographic algorithms can also be helpful to improve the model quality in regional applications, there is no definitive universal solution. The results also show that SDR models should always be calibrated and evaluated against sediment yields and SDR. With this approach, a new European soil loss map and an improved SDR model for river catchments north of the Alps and in Southeast Europe are derived. For other parts of Europe, the SDR model is of limited use. The studies on the annual variability of soil erosion reveal that seasonally weighted rainfall data is more appropriate than unweighted data. Despite satisfactory model results, neither the careful algorithm choice nor model improvements overcome the limitations of pan-European SDR models. These limitations are related to the mismatch of modelled soil loss processes and the relevant processes contributing to the observed or critical sediment load as well as the extraordinary sediment mobilisation during floods. Therefore, further research on integrating non-USLE processes and heavy-rainfall data as well as on disaggregating critical yields is needed.
40
Kuncoro, Andreas. "Employing Quality Management Principles to Improve the Performance of Educational Systems: An Empirical Study of the Effect of ISO 9001 Standard on Teachers and Administrators Performance in the Indonesian Vocational Education System." Doctoral diss., University of Central Florida, 2013. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/5966.
Full textAbstract:
ISO 9001 has been world widely implemented in both manufacturing and service organizations. A lot of studies have been conducted to investigate the effects of ISO 9001 implementation on the performance of these organizations. Most of these studies show that ISO 9001 implementation realized positive operational improvements and financial success.
Building on the merits of successful implementation of ISO 9001 quality management system in manufacturing and service, educational institutions have been attempted to adopt it in their operations. Even though there are studies relating ISO implementation to education, no research has been done to investigate the effects of ISO 9001 at the individual level.
The objective of this research is to investigate the effects of ISO 9001 quality management implementation on the performance of administrators and teachers. The Indonesian vocational education system is selected as a case example as there is a significant number of such institutions in Indonesia that attempt to achieve ISO certification and there is a national need to improve the performance of vocational education. It is a challenge to assess objectively the degree of ISO 9001 implementation in this specific educational context because of the size and diversity. This study relies on survey that measures the respondents' perception. Hence, this study applies a self-reported survey based performance measurement. The questionnaires are developed based on extensive literature review. Partial Least Squares Structural Equation Modeling (PLSSEM) has been used to examine the relationships between the different elements of quality management systems, quality culture; administrator and teacher performances.
The study is able to examine multiple interrelated dependence and subsequent relationships simultaneously among examined factors such as teacher and administrator performance, existing quality culture and ISO principles; and to incorporate variables that cannot be directly measured, such as leadership, for example. The findings of this study show that ISO 9001 implementation has positive significant effect on the performance of the vocational school administrator and teacher. The study also identifies key influencing elements of the ISO quality management system and examines their direct and indirect relationships with teacher and administrator performances. This study is expected to improve the current practices in implementing ISO and quality culture in any educational settings, specifically in the case of vocational educational system.Ph.D.
Doctorate
Industrial Engineering and Management Systems
Engineering and Computer Science
Industrial Engineering
41
Filippin, Livio. "Relativistic study of electron correlation effects on polarizabilities, two-photon decay rates, and electronic isotope-shift factors in atoms and ions: ab initio and semi-empirical approaches." Doctoral thesis, Universite Libre de Bruxelles, 2017. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/261670.
Full textAbstract:
The first aim of this thesis is to perform relativistic calculation of atomic and ionic polarizabilities and two-photon decay rates. Hydrogenic systems are treated by the Lagrange-mesh method. The extension to alkali-like systems is realized by means of a semiempirical-core-potential approach combined with the Lagrange-mesh method. The studied systems are partitioned into frozen-core electrons and an active valence electron. The core orbitals are defined by a Dirac-Hartree-Fock (DHF) calculation using the GRASP2K package. The valence electron is described by a Dirac-like Hamiltonian involving a core-polarization potential to simulate the core-valence electron correlation. Polarizabilities appear in a large number of fields and applications, namely in cold atoms physics, metrology and chemical physics. Two-photon transitions are part of a priori highly unlikely processes and are therefore called forbidden radiative processes. Experimental situations report decays from metastable excited states through these channels. Long lifetimes were measured for highly charged Be-like ions in recent storage-ring experiments, but their interpretation is problematic. The study of the competition between forbidden (one-photon beyond the dipole approximation, or multi-photon) and unexpected (hyperfine-induced or induced by external magnetic fields) radiative processes is all obviously relevant. The second aim of this thesis is to perform relativistic ab initio calculations of electronic isotope-shift (IS) factors by using the multiconfiguration DHF (MCDHF) method implemented in the RIS3/GRASP2K and RATIP program packages. Using the MCDHF method, two different approaches are adopted for the computation of electronic IS factors for a set of transitions between low-lying levels of neutral systems. The first one is based on the estimate of the expectation values of the one- and two-body nuclear recoil Hamiltonian for a given isotope, including relativistic corrections derived by Shabaev, combined with the calculation of the total electron densities at the origin. In the second approach, the relevant electronic factors are extracted from the calculated transition shifts for given triads of isotopes. These electronic quantities together with observed ISs between different pairs of isotopes provide the changes in mean-square charge radii of the atomic nuclei. Within this computational approach for the estimation of the mass- and field-shift factors, different models for electron correlation are explored in a systematic way to determine a reliable computational strategy, and to estimate theoretical error bars of the IS factors.Doctorat en Sciences de l'ingénieur et technologie
info:eu-repo/semantics/nonPublished
42
Justino, Josivan Ribeiro. "Estimativas de mortalidade para a regi?o nordeste do Brasil em 2010: uma associa??o do m?todo demogr?fico equa??o geral de balanceamento, com o estimador bayesiano emp?rico." Universidade Federal do Rio Grande do Norte, 2013. http://repositorio.ufrn.br:8080/jspui/handle/123456789/13859.
Full textAbstract:
Made available in DSpace on 2014-12-17T14:23:30Z (GMT). No. of bitstreams: 1
JosivanRJ_DISSERT.pdf: 3858170 bytes, checksum: cf220eba177815a3f2e7efdc0fc51b69 (MD5)
Previous issue date: 2013-08-15One of the greatest challenges of demography, nowadays, is to obtain estimates of mortality, in a consistent manner, mainly in small areas. The lack of this information, hinders public health actions and leads to impairment of quality of classification of deaths, generating concern on the part of demographers and epidemiologists in obtaining reliable statistics of mortality in the country. In this context, the objective of this work is to obtain estimates of deaths adjustment factors for correction of adult mortality, by States, meso-regions and age groups in the northeastern region, in 2010. The proposal is based on two lines of observation: a demographic one and a statistical one, considering also two areas of coverage in the States of the Northeast region, the meso-regions, as larger areas and counties, as small areas. The methodological principle is to use the General Equation and Balancing demographic method or General Growth Balance to correct the observed deaths, in larger areas (meso-regions) of the states, since they are less prone to breakage of methodological assumptions. In the sequence, it will be applied the statistical empirical Bayesian estimator method, considering as sum of deaths in the meso-regions, the death value corrected by the demographic method, and as reference of observation of smaller area, the observed deaths in small areas (counties). As results of this combination, a smoothing effect on the degree of coverage of deaths is obtained, due to the association with the empirical Bayesian Estimator, and the possibility of evaluating the degree of coverage of deaths by age groups at counties, meso-regions and states levels, with the advantage of estimete adjustment factors, according to the desired level of aggregation. The results grouped by State, point to a significant improvement of the degree of coverage of deaths, according to the combination of the methods with values above 80%. Alagoas (0.88), Bahia (0.90), Cear? (0.90), Maranh?o (0.84), Para?ba (0.88), Pernambuco (0.93), Piau? (0.85), Rio Grande do Norte (0.89) and Sergipe (0.92). Advances in the control of the registry information in the health system, linked to improvements in socioeconomic conditions and urbanization of the counties, in the last decade, provided a better quality of information registry of deaths in small areas
Um dos grandes desafios atuais da demografia ? obter estimativas de mortalidade, de maneira consistente, principalmente em pequenas ?reas. A car?ncia destas informa??es, dificulta a??es de sa?de p?blica e leva ao comprometimento da qualidade de classifica??o de ?bitos, gerando preocupa??o por parte dos dem?grafos e epidemiologistas na obten??o de estat?sticas confi?veis da mortalidade no Pa?s. Neste contexto, o objetivo deste trabalho ? obter estimativas de fatores de ajuste de ?bitos para corre??o da mortalidade adulta, por estados, mesorregi?es e grupos et?rios na regi?o nordeste, em 2010. A proposta est? pautada sobre duas linhas de observa??o: uma demogr?fica e outra estat?stica, considerando tamb?m duas ?reas de abrang?ncia nos estados da regi?o Nordeste, as mesorregi?es como ?reas maiores e os munic?pios como pequenas ?reas. O principio metodol?gico ? usar o m?todo demogr?fico Equa??o Geral e Balanceamento ou General Growth Balance, para corrigir os ?bitos observados, nas ?reas maiores (mesorregi?es) dos estados, por estas serem regi?es menos prop?cias a quebra dos pressupostos metodol?gicos. Em seguida, ser? aplicado o m?todo estat?stico estimador bayesiano emp?rico, considerando como soma dos ?bitos nas mesorregi?es, o valor de ?bito corrigido pelo m?todo demogr?fico e como refer?ncia de observa??o de ?rea menor os ?bitos observados nas pequenas ?reas (munic?pios). Como resultados desta combina??o, um efeito de suaviza??o do grau de cobertura dos ?bitos ? obtido, fruto da associa??o com o estimador bayesiano emp?rico e a possibilidade de avaliar o grau de cobertura de ?bitos por grupos et?rios em n?vel de munic?pios, mesorregi?es e estado, com a vantagem de estimar fatores de ajuste, conforme o n?vel de agrega??o desejado. Os resultados agrupados por estado, apontam para uma melhora significante do grau de cobertura de ?bitos, segundo a combina??o dos m?todos com valores acima de 80%. Alagoas (0,88), Bahia (0,90), Cear? (0,90), Maranh?o (0,84), Para?ba (0,88), Pernambuco (0,93), Piau? (0,85) , Rio Grande do Norte (0,89) e Sergipe (0,92). Os avan?os no controle do registro das informa??es no sistema de sa?de, associado ?s melhorias nas condi??es socioecon?micas e de urbaniza??o dos munic?pios, na ?ltima d?cada, proporcionaram uma melhor qualidade do registro das informa??es de ?bitos nas pequenas ?reas
43
Yang, Ma Ga. "Developing a Focal Firm’s Sustainable Supply Chain Framework: Drivers, Orientation, Practices and Performance Outcomes." University of Toledo / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1356543598.
Full text
44
Wyckoff, Peter S. (Peter Scott). "Numerical solution of differential equations through empirical eigenfunction expansions." Thesis, Massachusetts Institute of Technology, 1995. http://hdl.handle.net/1721.1/29872.
Full text
45
Eftang, Jens Lohne. "Reduced basis methods for parametrized partial differential equations." Doctoral thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for matematiske fag, 2011. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-12550.
Full text
46
Garven, Elizabeth A. "Review of the empirical equations for predicting the shear strength of unsaturated soils." Thesis, University of Ottawa (Canada), 2009. http://hdl.handle.net/10393/28344.
Full textAbstract:
Shear strength is a key engineering property required in the design of several geotechnical structures that include earth dams, pavements, slopes, retaining walls and foundations. In many situations these structures are constructed with unsaturated soils or in soils that are placed in a state of unsaturated condition. The designs of these structures are based on conventional soil mechanics assuming that the soil is in a state saturated condition resulting in conservative estimations.
Several experimental techniques are presently available and more are evolving for determining the shear strength of unsaturated soils in the laboratory environment in this emerging research area that is of significant practical interest. However, these experimental techniques are expensive, time consuming and need elaborate testing equipment. In addition, qualified and trained personnel are required for reliably determining the shear strength behaviour of unsaturated soils. Due to these reasons, the focus of investigations in recent years has been directed towards predicting the shear strength of unsaturated soils. There are several techniques that include semi-empirical, empirical and mathematical fitting relationships that can be used in the prediction or estimation of the variation of shear strength of unsaturated soils with respect to suction. Such techniques are encouraging towards extending the mechanics of unsaturated soils into engineering practice.
In spite of recent advances in the field of unsaturated soils, few practitioners have background with respect to the shear strength behaviour and the mechanics of unsaturated soils. This thesis provides a historical background of the development of concepts related to our present understanding of the shear strength behaviour of unsaturated soils. The techniques of interpreting the shear strength behaviour proposed by various investigators are also summarized. The details presented in the thesis also include the state-of-the-art testing procedures for determining the shear strength behaviour. In addition, a wealth of 130 soils data published in the literature from various conferences and journals from all over the world are summarized.
There are twenty-five different equations that are available in the literature to predict the variation of shear strength with respect to suction using different techniques. All these techniques are summarized providing details of the philosophies used in the development of these equations. Thirteen of the above equations use the soil-water characteristic curve (SWCC) and the saturated shear strength parameters (c' and &phis;') for predicting the shear strength of unsaturated soils. Other techniques that include mathematical fitting models and empirical relationships for estimating the shear strength of unsaturated soils are also summarized.
Seven prediction equations commonly used in the literature are chosen from the available 25 equations in the literature to predict the variation of shear strength with respect to suction using 130 data sets of published experimental results from the literature. A quantitative assessment method is used in comparing the predicted and measured shear strength results of the 130 sets. Each of the seven prediction equations is able to successfully predict the variation of shear strength with respect to suction for some of the soils; however, approximately 8% of the soils were not able to be successfully predicted by any of the 7 equations.
The shear strength behaviour of unsaturated soils if a complex relationship which is dependent on many factors including stress history, density, soil structure or fabric, water content, volume change behaviour during shearing state and testing techniques. For example, recent developments in shear strength testing techniques show that previously measured water content in samples may not be representative of the actual water content due to diffused air, condensation and evaporation in the system. In other words, the simple prediction procedures that are available in the literature are not capable of taking into account many complex parameters that influence the shear strength behaviour of unsaturated soils. Therefore, the available techniques or procedures have to be used in practice with engineering judgment while predicting the shear strength of unsaturated soils. Some guidelines and recommendations are provided with respect to the available prediction procedures such that practicing engineers and other investigators can use them understanding the strengths and weaknesses. Finally, the research work summarized in this thesis is also useful for other investigators to undertake future work in the area of shear strength of unsaturated soils to better understand its behaviour.
47
Negreiros, Jefferson Ronald Quaresma. "RelaÃÃes simplificadas para a estimativa do assoreamento de reservatÃrios." Universidade Federal do CearÃ, 2014. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=13679.
Full textAbstract:
Esta pesquisa apresenta uma sÃntese das taxas de assoreamento observadas
em reservatÃrios brasileiros, onde foram identificadas taxas de assoreamento
variando aproximadamente de 1 a 7% do volume inicial por dÃcada (inferiores Ã
mÃdia mundial de 10%), sendo os reservatÃrios localizados no Estado do
Cearà aqueles que possuem menores taxas, provavelmente devido Ãs densas
redes de reservatÃrios existentes nas bacias de contribuiÃÃo. Verificou-se
tambÃm uma tendÃncia geral de decaimento das taxas de assoreamento com o
volume inicial dos reservatÃrios. Em seguida, foram desenvolvidos dois
mÃtodos expeditos para estimativa do assoreamento de reservatÃrios, os quais
sÃo baseados em correlaÃÃes empÃricas ajustadas a partir de dados de campo,
e com este mesmo objetivo foi realizada a aplicaÃÃo da Metodologia de Lima
Neto et al. (2011) para os reservatÃrios brasileiros. Os mÃtodos propostos sÃo
mais simples que as metodologias existentes na literatura, e dependem
basicamente da pluviometria nas bacias de contribuiÃÃo e do volume inicial dos
reservatÃrios. As diferenÃas observadas entre as diferentes metodologias
foram inferiores a 30% . Este dado sugere que qualquer um dos trÃs mÃtodos
pode ser utilizado para estimar o assoreamento de reservatÃrios, em nÃvel de
planejamento. PorÃm, vale ressaltar que apesar da praticidade/simplicidade
das equaÃÃes propostas, mediÃÃes de campo e/ou modelos mais sofisticados
continuam sendo necessÃrios para se avaliar de forma mais precisa o
assoreamento de reservatÃrios.This research provides an overview of sedimentation rates observed in Brazilian reservoirs, where sedimentation rates were identified ranging approximately 1 to 7% of the starting volume per decade (the lower world average of 10%), and the reservoirs in the State of Cearà those with lower rates, probably due to dense existing reservoirs networks in contribution basins. It was found also a general trend of decay of sedimentation rates with initial volume of the reservoirs. Then we developed two empirical methods to estimate reservoir sedimentation, which are based on empirical correlations adjusted from field data, and with this same goal was carried out the implementation of Lima Methodology Neto et al. (2011) for the Brazilian reservoirs. The proposed methods are simpler than the existing methods in the literature, and depend basically the rainfall in contribution basins and the initial volume of reservoirs. The differences observed between the different methodologies were less than 30%. This suggests that any of the three methods can be used to estimate reservoir sedimentation in level planning. However, it is noteworthy that despite the practicality / simplicity the proposed equations, field measurements and / or more sophisticated models still needed to assess more accurately the reservoir sedimentation.
48
Shankar, Venkataraman N. "Limited dependent variable and structural equations models : empirical applications to traffic operations and safety /." Thesis, Connect to this title online; UW restricted, 1997. http://hdl.handle.net/1773/10179.
Full text
49
Wu, Fan. "The extended empirical likelihood." Thesis, 2015. http://hdl.handle.net/1828/6124.
Full textAbstract:
The empirical likelihood method introduced by Owen (1988, 1990) is a powerful
nonparametric method for statistical inference. It has been one of the most researched
methods in statistics in the last twenty-five years and remains to be a very active
area of research today. There is now a large body of literature on empirical likelihood
method which covers its applications in many areas of statistics (Owen, 2001).
One important problem affecting the empirical likelihood method is its poor accuracy,
especially for small sample and/or high-dimension applications. The poor
accuracy can be alleviated by using high-order empirical likelihood methods such as
the Bartlett corrected empirical likelihood but it cannot be completely resolved by
high-order asymptotic methods alone. Since the work of Tsao (2004), the impact of
the convex hull constraint in the formulation of the empirical likelihood on the finite sample
accuracy has been better understood, and methods have been developed to
break this constraint in order to improve the accuracy. Three important methods
along this direction are [1] the penalized empirical likelihood of Bartolucci (2007)
and Lahiri and Mukhopadhyay (2012), [2] the adjusted empirical likelihood by Chen,
Variyath and Abraham (2008), Emerson and Owen (2009), Liu and Chen (2010) and
Chen and Huang (2012), and [3] the extended empirical likelihood of Tsao (2013) and
Tsao and Wu (2013). The latter is particularly attractive in that it retains not only
the asymptotic properties of the original empirical likelihood, but also its important
geometric characteristics. In this thesis, we generalize the extended empirical likelihood
of Tsao and Wu (2013) to handle inferences in two large classes of one-sample
and two-sample problems.
In Chapter 2, we generalize the extended empirical likelihood to handle inference
for the large class of parameters defined by one-sample estimating equations, which
includes the mean as a special case. In Chapters 3 and 4, we generalize the extended
empirical likelihood to handle two-sample problems; in Chapter 3, we study the extended
empirical likelihood for the difference between two p-dimensional means; in
Chapter 4, we consider the extended empirical likelihood for the difference between
two p-dimensional parameters defined by estimating equations. In all cases, we give
both the first- and second-order extended empirical likelihood methods and compare
these methods with existing methods. Technically, the two-sample mean problem
in Chapter 3 is a special case of the general two-sample problem in Chapter 4. We
single out the mean case to form Chapter 3 not only because it is a standalone published
work, but also because it naturally leads up to the more difficult two-sample
estimating equations problem in Chapter 4. We note that Chapter 2 is the published paper Tsao and Wu (2014); Chapter 3 is
the published paper Wu and Tsao (2014). To comply with the University of Victoria
policy regarding the use of published work for thesis and in accordance with copyright
agreements between authors and journal publishers, details of these published work
are acknowledged at the beginning of these chapters. Chapter 4 is another joint paper
Tsao and Wu (2015) which has been submitted for publication.Graduate
0463
fwu@uvic.ca
50
Lin, Kuo-tai, and 林國泰. "Empirical Study of Residential Smart Meter Adoption Using Structural Equation Modeling." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/57131745177525597409.
Full textAbstract:
碩士國立臺灣科技大學
營建工程系
103
Global warming and extreme weather have been increasingly severe in recent years, prompting countries worldwide to pay attention to energy conservation and sustainable development. Power supply is closely related to the economic development and daily needs of the people in a country. However, in Taiwan, the infrastructure of electrical grids in the consumer end is deteriorating, which intangibly results in additional electricity losses. Thus, numerous developed countries have actively developed alternative energy sources and formulated measures and management strategies to reduce energy consumption. In the recent development of power management, numerous countries have proposed using smart meters for energy-conservation control. Specifically, they intend to use an automatic energy consumption monitoring system to record the electricity consumption pattern of consumers, thereby optimizing an electricity consumption trend and improving the efficiency of energy usage. Taiwan is currently at the initial stage of smart grid deployment. Smart meters have not been widely installed to monitor residential electricity consumption; therefore, investigating the adoption propensity and implementation strategies of smart meters in residential buildings is a critical research topic at present. This study began with a literature review to identify the factors considered by users in their actual adoption of smart meters and subsequently assessed general residential consumers’ acceptance degree of contemporary technologies. Structured questionnaires were used to interview a randomly selected sample to quantify users’ expected acceptance degree to the use of smart meters. Structural equation modeling was employed to verify the explanatory power between assessment criteria and dimensions. Based on the analysis result, the consumer adoption propensity index was employed as the baseline for the current consumers’ willingness to use smart meters. A two-dimensional analysis based on index importance and perceptions of potential users was conducted to identify the crucial index that influenced the adoption propensity. The indicatiors served as the feedback for the basis of subsequent implementation strategies. Implications were discussed qualitatively at the end of this paper. The analytical findings clarify the primary factors considered by consumers and can be used to assess the intention of people to install smart meters. Therefore, energy management authorities can adopt a social and humanistic perspective to continually enhance strategies for technology marketing, thereby achieving the goals of energy conservation and sustainable development.