dissertation com dez 1999 (20 résultats)

Taschenbuch. Etat : Neu. Neuware - Quasi-Monte Carlo methods, which are often described as deterministic versions of Monte Carlo methods, were introduced in the 1950s by number theoreticians. They improve several deficiencies of Monte Carlo methods; such as providing estimates with deterministic bounds and avoiding the paradoxical difficulty of generating random numbers in a computer. However, they have their own drawbacks. First, although they provide faster convergence than Monte Carlo methods asymptotically, the advantage may not be practical to obtain in 'high' dimensional problems. Second, there is not a practical way to measure the error of a quasi-Monte Carlo simulation. Finally, unlike Monte Carlo methods, there is a scarcity of error reduction techniques for these methods. In this dissertation, we attempt to provide remedies for the disadvantages of quasi-Monte Carlo methods mentioned above. In the first part of the dissertation, a hybrid-Monte Carlo sequence designed to obtain error reduction in high dimensions is studied. Probabilistic results on the discrepancy of this sequence as well as results obtained by applying the sequence to problems from numerical integration and mathematical finance are presented. In the second part of the dissertation, a new hybrid-Monte Carlo method is introduced, in an attempt to obtain a practical statistical error analysis using low-discrepancy sequences. It is applied to problems from mathematical finance and particle transport theory to compare its effectiveness with the conventional methods. In the last part of the dissertation, a generalized quasi-Monte Carlo integration rule is introduced. A Koksma-Hlawka type inequality for the rule is proved, using a new concept for the variation of a function. As a consequence of the rule, error reduction techniques and in particular an 'importance sampling' type statement are derived.Problems from different disciplines are used as practical tests for our methods. The numerical results obtained in favor of the methods suggest the practical advantages that can be realized by their use in a wide variety of applications.

Taschenbuch. Etat : Neu. Neuware - The problem this project attempts to solve is to develop a workable moral education in light of the clash between religious forms of moral education and U.S. Supreme Court decisions concerning them. The concept of story and storytelling has been suggested as a unifying focus for disparate prescriptions for moral education. Several recent approaches to moral storytelling have been proposed. The approaches of William Bennett, Nel Noddings, and Herbert Kohl are among those which have attempted to combine moral education and storytelling within the last decade. Bennett is identified with other theorists whose primary concern is the moral content of a story. Noddings is identified as a process theorist, whose primary concern is the process of moral storytelling, not the content. Kohl is identified as a reflection theorist, whose approach challenges tradition in the hope of creating a more moral society. Each one of these three approaches attempts to provide a comprehensive program of moral education, but they fall short of that goal. The purpose of this project, then, is to construct a storytelling moral education program that improves upon earlier approaches.Using the three levels of moral thinking posited by R.M. Hare, a three-level approach to moral storytelling is proposed. The intuitive, critical, and meta-ethical levels of moral thinking that Hare refers to are used to frame a new, three-level, approach to moral storytelling. The three-level approach combines content, process, and reflection into a unified prescription for moral education. Thus, a more comprehensive plan for moral education through storytelling is developed, one that respects traditional forms of moral education while remaining within the parameters set by the U.S. Supreme Court.

Taschenbuch. Etat : Neu. Neuware - The effect of video and written modeling on self-efficacy of 70 master's degree students enrolled in their first techniques course was investigated. The ability to understand and use reflection of content, feeling, and meaning was presented to the experimental group through videotaped instruction and examples and the control group through written instruction and examples. Facts about reflecting skills, which included information and three vignettes, demonstrated the use of the skills. Through two pilot studies, the Reflecting Skills Questionnaire (RSQ) developed for this study showed convergent validity with the Counseling Self-Estimate Inventory (COSE). Participants' indication of self-efficacy for the reflection of content, feeling, and meaning was assessed by the RSQ. A t - test was computed to determine whether video or written treatment had an effect on the self efficacy of counselors in training. Using a two-tailed t - test for independent groups, no significant difference (p > .05) was found.

Taschenbuch. Etat : Neu. Neuware - Scope of Study: This dissertation investigates the effect of cost and dose on the hemodialysis treatment modality. This modality of dialysis is an alternative to renal transplantation for people diagnosed with end-stage renal disease. The mortality rate is used as a quality indicator of the hemodialysis treatment by assessing the quality of service in Colombia and comparing it with the quality of service in the United States.Findings and Conclusions: The hypothesis testing used in this research shows that there is a significant difference between the delivered dose of hemodialysis in Colombia and the United States. The mortality rate for patients in hemodialysis in Colombia for a comparable age group (45-64) is higher than that of the United States. This is attributed in great part to the effect of the hemodialysis dose on the treatment. A simple linear regression shows a strong negative relationship between mortality rate and dose. Cost also has an impact on the quality of service of the hemodialysis therapy. Nevertheless, a direct relationship between cost and mortality rate could not be established. Factors such as patient's vascular access and dialyzer flow rates are not evaluated in this investigation.

Taschenbuch. Etat : Neu. Neuware - As distance education schools grow in popularity, contemporary educators are raising important instructional questions about quality of these programs. A vital question involves concerns about the level of interactivity or interaction between students and between teachers and students. Interactivity is a challenging subject because there are few research studies that address the issue. It is a dynamic entity that involves a number of important elements, but the researcher stressed three vital elements: communication, participation, and feedback. The study highlights research results from a survey of students who were pursuing on-line graduate degrees (masters and doctoral). Important distance education issues are discussed such as feedback from professors and the quality of academic dialog during a computer-mediated class. The text offers a relevant analysis of interactivity that should help distance educators and administrators in their quest to develop programs that meet the needs of todayÍs adult learners.

Taschenbuch. Etat : Neu. Neuware - Scope of Study: This dissertation summarizes the current use of concurrent software engineering (CSE) by information technology (IT) organizations in the United States and its effectiveness in improving software delivery time, quality, and cost. From a total population of 7,173 IT organizations, a one-third sample of 2,391 were surveyed. A net valid response of 142 organizations was received, which represents a valid return rate of 6.2 percent. The responses were then analyzed against software development time, quality, and cost metrics according to the software development methodologies used. Findings and Conclusions: This study shows the extent to which pure CSE and CSE in combination with the traditional system development life cycle (SDLC) are used in the United States. There are strong indications that CSE improves software development time and cost, but this could not be statistically proven from the data. There is no indication that CSE improves software quality.

Taschenbuch. Etat : Neu. Neuware - The problem of controlling sensory perception for use in discrete event feedback control systems is addressed in this thesis. The sensory perception controller (SPC) is formulated as a sequential Markov decision problem. The SPC has two main objectives; 1) to collect perceptual information to identify discrete events with high levels of confidence.

Taschenbuch. Etat : Neu. Neuware - That neuropsychological performance is impaired in patients with affective disorders is now widely accepted, and there is growing evidence that attentional dysfunction (effortful attention in particular) is one of the major impairments normally observed. The present study aimed at defining the nature of attentional dysfunction in depression by means of tests designed to measure specific aspects of attention, such as sustained, selective, focused, divided attention, etc. We also tested the effect of increasing effortful attentional demands on subjects' performance. To that end, effort level was increased on the task variable that was considered to be the defining characteristic of each task. For example, the Stroop Color-Word is a test of perceptual interference, so that on the high effort condition we presented two types of interference - visual as well as auditory (recorded messages). Fourteen unipolar and thirteen bipolar patients were recruited from the inpatient psychiatry unit at the University of Massachusetts Medical Center, based on DSM-III criteria and score on the Inventory to Diagnose Depression (IDD). An age and education matched control group (N=20) was recruited from hospital workers. Subjects were administered a battery of twenty neuropsychological tests, including: Computerized Stroop Test, Continuous Performance Test, Trail Making, Symbol-Digit Modalities Test, Finger Tapping & Controlled Word Generation, Visual Letter Search, Digit Span, and a Levels of Processing Memory task. For each of these tasks, a low and high effort levels were employed. Subjects filled out two self-report scales, Fatigue Assessment Inventory and Profile of Mood States, before and after testing. Both unipolar and bipolar patients exhibited severe depression as measured by the IDD. ANOVA procedures indicated that on most measures patients performed significantly poorly when compared to normal controls (p.

Taschenbuch. Etat : Neu. Neuware - 'The New World Order' is anything but new, it has been evolving for over 100 years. This thesis begins with the idea for an elite establishment of one late 19th century individual, and shows how it developed into the many organizations that make up the global regime of today.

Taschenbuch. Etat : Neu. Neuware - This study explores the emergence and development of the conservation movement in Argentina during the twentieth century. I argue that the development of the conservation movement has been linked to shifts in the broader spectrum of Argentina's political arena as well as the international political situation as nations competed for the sovereignty of newly acquired territories after the Indian Wars. This book explores the development of Argentina as a nation in relation to conservation of its natural resources as a counter measure to resource extraction. Thus, I establish the relationship between the need for national sovereignty and socio-economic development via the formulation of nature based tourism industry. This strategy was developed by Excequiel Bustillo and spearheaded by the formation of National Park System. The environmental movement in Argentina has been based on the principles of utilitarianism, and the National Park System of Argentina was instrumental in establishing hegemonic national identity and sovereignty in Patagonia. The National Park System institutionalized and for many years was the leading force behind conservation of Argentina's natural resources, and it fostered social and economic development of remote areas through nature based tourism practices.

Taschenbuch. Etat : Neu. Neuware - During the adolescent years, young people seek to leave behind childhood and the age of 'informed consent'--i.e, the years when adults informed and expected children to consent! Teenagers strive for adult roles and passionately seek ways to prove their maturity to themselves, peers, and adults. This quest for adult roles leads teens through a variety of rites of passage both formal and informal. Some rites of passage which involve youth/adult partnerships delineate the movement from childhood to adulthood in positive ways while young people (psychological orphans) who do not have adult support for rites of passage often create their own rites which involve dangerous risk-taking and destructive behavior.Aching to Age explores rites of passage both ancient and modern, formal and informal; examines the place of these rites in meeting the adolescent psychological quest for adulthood (adult roles); and also explores popular cultural practices by adolescents who lack or eschew established rites of passage. Further, Aching to Age looks at the purpose of these rites in the lives of adolescents and finally explores the importance of rites of passage and how adults who interact with adolescents become partners with young people in the transition to adult roles and responsibilities.

Taschenbuch. Etat : Neu. Neuware - In this dissertation, a new spare capacity planning methodology is proposed utilizing path restoration. The approach is based on forcing working flows/traffic which are on paths that are disjoint to share spare backup capacity. The algorithm for determining the spare capacity assignment is based on genetic algorithms and is capable of incorporating non-linear variables such as non-linear cost function and QoS variables into the objective and constraints. The proposed methodology applies to a wider range of fault scenarios than most of the current literature. It can tolerate link-failures, node-failures, and link-and-node failures. It consists of two stages: the first stage generates a set of network topologies that maximize the sharing between backup paths by forcing them to use a subset of the original network. The second stage utilizes a genetic algorithm to optimize the set of solutions generated by the first stage to achieve an even better final solution. It can optimize the solution based on either minimizing spare capacity or minimizing the total network cost. In addition, it can incorporate QoS variables in both the objective and constraints to design a survivable network that satisfies QoS constraints.Numerical results comparing the proposed methodology to Integer Programming techniques and heuristics from the literature are presented showing the advantages of the technique. The proposed methodology was applied on 4 different size networks based on spare capacity optimization criteria and it was found that it achieved solutions that were on average 9.3% better than the optimal solution of the IP design that is based on link-restoration. It also achieved solutions that were on average 22.2 % better than the previous heuristic SLPA. The proposed methodology is very scalable. It was applied on networks with different sizes ranging from a 13-node network to a 70-node network. It was able to solve the 70-node network in less than one hour on a Pentium II PC. The curve-fitting of the empirical execution time of the methodology was found to be O(n3).

Taschenbuch. Etat : Neu. Neuware - This study is designed to show how personality dispositions and cognitive variables may combine with social norms to influence wife abuse. Prior research examining the role of individual differences in wife abuse has been sparse, unsystematic, and appear questionable for two reasons. First, these studies have not considered that contextual norms and cognitive variables are likely to interact with dispositional variables to either facilitate or discourage abuse.Second, the theoretical relationship between dispositional variables and macrolevel approaches (i.e. feminist and sociological) has not been investigated. How demographic variables, contextual norms, and individual differences interact may have important implications for the study of wife abuse.The present project addresses these issues by focusing on a description of the relationship between personality (authoritarianism & sex-role attitudes), cognitive variables (self-consciousness & the hostile attribution bias), contextual norms (military experience & regional background) and wife abuse.149 males completed a questionnaire containing the Conflict Tactics Scale, RWA scale, Self-Consciousness Scale, Adversarial Sexual Beliefs Scale, and the Attitudes Toward Women Scale. Furthermore, subjects responded to a variety of demographic items designed to assess income level, age, regional background, alcohol consumption, educational level, and military experience.Results suggest three principal conclusions. First, they show that the hostile attributional bias is the most powerful predictor of verbal and physical abuse. Analyses consistently indicated that subjects possessing hostile attributions toward women are the most likely to verbally and physically abuse their present partner.Second, the contextual norms and demographics emphasized in past models of abuse were found to interact with personality and cognitive variables. The effect of military experience, Southerness, and alcohol use were mediated by personality and cognitive variables. Finally, the present results are consistent with past studies showing that abusers consume more alcohol, are younger, and earn less than non-abusers. Insofar as the results show significant relationships between relevant of cognitive, personality, and contextual factors, they provide a new, more accurate description of the problem, and may allow more effective forms of prediction, intervention and treatment.

Taschenbuch. Etat : Neu. Neuware - Robert Siodmak, who is considered the master of film noir thrillers and crime melodramas, has long been seen as a mere 'assignment director,' never an artist in complete control of his work. J. Greco's study of Siodmak's Hollywood career dispels this view and presents a unique perspective on the studio system and the director who used cunning to get his own way within it. He incorporates both archival evidence and stylistic analysis to show a distinct correlation between the production histories of Siodmak's studio films and the director's central artistic purpose. Shedding new light on the career of this important film maker, this book is worthwhile reading for the film scholar, the lover of film noir, and the fan of Siodmak's work.

Taschenbuch. Etat : Neu. Neuware - Barriers which hinder career advancement of women are complex and varied. They have become top agenda items for most corporations and the gov-ernment. The 'glass ceiling' is a term that symbolizes a variety of barriers that prevent qualified individuals from advancing higher in their organization. Although many women hold management positions, few have made the breakthrough to top-level positions. To determine what conditions are required for women to attain top executive positions, an ethnographic study was conducted at a hospital. The study was limited to four women who held executive positions: one associate administrator, one interim associate administrator, one director and the CEO. An in-depth data gathering technique using observation, interviews and documentation was used to investigate factors such as education/skills, influences, support, barriers and corporate culture.The findings revealed: (a) having opportunities to be participating, valued family members and to compete in activities while young helps girls to develop a sense of competence and mastery; (b) education, credential building experiences, certain competencies and being willing to take risks are necessary for success; (c) having certain attitudes and philosophies are crucial factors in their success; (d) mentors, network involvement and relationships with peers does affect mobility; (e) the women did have a career plan, not in the sense of a linear career plan, but rather one in the form of the spiral career concept; (f) the hospital is a structure which provides opportunities to develop careers; (g) the women understand, accept and have learned to adapt to the culture of the society in which they live and work; (h) the women are savvy at expressing, affirming and communicating the substance of their culture to others; (i) the amount of prejudice a woman encountered depended upon several components; and (j) the barriers to advancement experienced by the women do not confirm those discussed in the review of literature.Further research is recommended on the qualifications of male and female CEOs, educational programs most appropriate for female executives, how successful female executives learned to deal with their barriers and why certain organizations do not have top female executives.

Taschenbuch. Etat : Neu. Neuware - America is a mobile nation and frequent relocation is a way of life for many corporate families. This qualitative review of literature relating to the sociological impact of relocation on the corporate family appears to show that relocation has short-term and long-term implications for the family system. Relocation is not an isolated event but a process of adjustment over time involving emotional stages similar to the stages of grief and loss. Each family member may experience the relocation differently and progress through the stages at a different rate. This creates a period of disorganization and disorientation for the family similar to a prolonged jet-lag, which I call Relo-Lag(TM). This period of adjustment for the family system is the most frequently cited short-term effect and can last up to two years. Frequent relocations may also precipitate a long-term effect by causing the family system to become too tightly closed. The family may not seek outside help when needed or accept it when offered. Individual family members may experience difficulty with long-term close friendships and relationships outside the family. In addition, children appear to be particularly vulnerable when relocating during the individuation stages, years 3-5 and adolescence, years 13-16. Not all families experience relocation negatively and some families cope well with relocation. Relocation can improve career and financial opportunities for some corporate families, but there may be emotional costs that need to be considered before making a decision to relocate.

Taschenbuch. Etat : Neu. Neuware - Despite evidence that 90% of violent crimes are committed by men, higher education professionals and researchers still understand relatively little about the process by which male students acquire the attitudes, knowledge, values and skills which serve as deterrents to perpetrating violence against women and against other men. Men Against Violence is a peer advocacy organization at a large, public Research I institution in the South which focuses on the special and unique responsibility men have to end violence. Through participation in a wide array of service learning, community action and leadership opportunities, MAV members challenge cultural norms which link masculinity with violence. Types of violence targeted by MAV include: fighting, domestic violence, rape, vandalism, hazing, harassment, hate crimes, homicide and suicide. Utilizing a sociological, public health perspective that incorporates theories of masculinity and models of student development, this dissertation is a case study of the organization Men Against Violence. It examines the ways in which a close-knit association of men generated and sustained an organizational culture that encourages and rewards non- violence among its members, as well as begins to reframe traditional conceptions of masculinity. Subjects for this study consisted of the eight male students who comprised the 1997-1998 Executive Board of MAV. Primary research questions were:(1) What are the characteristics of an organizational culture of non-violence that is created and maintained among a close-knit group of male college students (2) How can higher education professionals, particularly women, facilitate the process of creating such an organizational culture Chapter 1 addresses methodological concerns in the dissertation; Chapters 2 and 3 review current literature regarding men and campus violence; Chapter 4 provides a historical narrative of the founding and development of MAV; Chapter 5 presents cultural themes which emerged during content analysis of data from ethnographic interviews and participant- observation; and Chapter 6 offers theoretical and practical implications of the study.

Taschenbuch. Etat : Neu. Neuware.

Taschenbuch. Etat : Neu. Neuware - This work is concerned with the evaluation of rhetoric as an essential aspect of Renaissance sensibility. It is an analysis of the Renaissance world viewed in terms of literary style and aesthetic. Eight plays are analysed in some detail: four by George Peele: The Battle of Alcazar, Edward I, David and Bethsabe, and The Arraignment of Paris; and four by Christopher Marlowe: Dido Queen of Carthage, Tamburlaine Part One, Dr Faustus and Edward II. The work is thus partly a comparative study of two important Renaissance playwrights; it seeks to establish Peele in particular as an important figure in the history and evolution of the theatre. Verbal rhetoric is consistently linked to an analysis of the visual, so that the reader/viewer is encouraged to assess the plays holistically, as unified works of art. Emphasis is placed throughout on the dangers of reading Renaissance plays with anachronistic expectations of realism derived from modern drama; the importance of Elizabethan audience expectation and reaction is considered, and through this the wider artistic sensibility of the period is assessed.

Taschenbuch. Etat : Neu. Neuware - The study of Multivariate Time Series has always been more difficult at the modeling stage than the univariate case. Identification of a suitable model, questions of stability, and the difficulties of prediction are well recognised. A variety of methods appear to be worth examining. This thesis is concerned with the proposal of an useful tool which is to apply canonical analysis to a realisation of a Multivariate Time Series and concentrates it's attention on k-variate ARMA(p,q) models. The multivariate series is partitioned into two overlapping or non-overlapping sets of different sizes. The left set is kept at lag 0 (without loss of generality) and the right set at a sequence of lags s=0,1, . The model includes the possibility that the same subset of variables belong to the left set at lag 0 and to the right set at lag s. A technique for dimension reduction is suggested. We tried to elucidate identification and the internal structure of time-dependence at several pairs of lags as a tool for identification. As the technique suggested provide a method of investigation of patterns of interrelations between two multivariate sets or subsets of variables with a joint distribution, it is an efficient tool for use in multivariate series of economic data. A review of the basic models of Multivariate Time Series is given and their canonical auto and cross correlation analysis is presented. In order to study the asymptotic distribution, several Monte Carlo experiments were necessary. We attempted to provide information through simulation about the distributional and other statistical properties for the canonical statistics obtained by our procedures. New software is provided and data experience is given. The first computer program provides us with information, graphs for the canonical auto and cross correlations, test statistics for the 'useful' canonical auto and cross correlations as well as the left and right eigenvectors, left and right intraset and interset matrices of correlations, proportions of variances extracted by the canonical variates of the left and of the right sets and left and right redundancies for lags s=0,1, .The second program gives similar calculations for the k-variate ARMA(p,q) models when the matrices of parameters and variance-covariance matrix of the error are known. The third program provides us with the mean value, minimum and maximum values, excess kurtosis, histogram and cumulative distribution for each one of the canonical auto and cross correlations at every lag s calculated from several simulations of Monte Carlo generated k-variate ARMA(p,q) models when the matrices of parameters and variance-covariance matrix of the error are given or when they are generated. The second part of the thesis is devoted to the generalisation of the robust and practically useful univariate Holt-Winters model. We developed formula for the Multivariate Additive Holt-Winters (Seasonal and Non-Seasonal) to the point of application and its reduction to Moving Average form. New software is produced. The link between the two main themes consists on the canonical analysis of a Multivariate Holt-Winters from its reduced MA form and reducing its dimension as well as detecting the basic linear relationships between variables, between and within several lags. We also attempted to investigate the effect of outliers, the removal of non-stationary trends via cubic spline fitting , differencing as well as transformations such as loge (data).