• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 41
  • 26
  • 25
  • 8
  • 2
  • 1
  • 1
  • Tagged with
  • 107
  • 107
  • 35
  • 33
  • 31
  • 31
  • 28
  • 21
  • 20
  • 19
  • 17
  • 17
  • 13
  • 12
  • 12
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

Prostate Cancer in High-Risk Population

Nair, Rasmi Girijavallabhan January 2018 (has links)
In 2018, the United States Preventive Services Task Force (USPSTF) recommended that African American men and those with a family history of prostate cancer should discuss the pros and cons of PSA testing with their physician and engage in shared decision making. Identifying risk factors of prostate cancer, calculating individualized prediction of the risk of prostate cancer, and ensuring that the patients are well informed with knowledge to understand these risks so as to easily make decisions, are extremely important in shared decision making. The overarching goal of this dissertation is to assist in these three steps and facilitate shared decision making in a high-risk population. Aim 1 assessed the association of demographic characteristics, clinical markers and genitourinary symptoms with the diagnosis of prostate cancer (Aim 1a), as well as with the diagnosis of significant prostate cancer (Aim 1b), in a high-risk population. A nested case-control study for Aim 1a and a case-control study for Aim 1b was conducted using the Prostate Risk Assessment Program (PRAP) data, which enrolls African American men and those with a family history of prostate cancer. Multivariate conditional logistic regression was used to assess the association between the risk factors for any prostate cancer, while multivariate logistic regression was used for clinically significant prostate cancer. The risk of any prostate cancer increased with increasing age, presence of family history and increasing PSA levels, while the risk of significant prostate cancer was associated with increasing PSA level. This suggests that PSA level, as a continuum, is extremely important while predicting prostate cancer, especially significant prostate cancer within a high-risk population. Using Aim 2, we compared the performance of two prostate cancer risk calculators, Prostate Cancer Prevention Trial – Risk Calculator 2.0 (PCPT-RC 2.0) and the European Randomized Study of Screening for Prostate Cancer -Risk Calculator 3/5 (ERSPC-RC 3/5) to predict any prostate cancer and clinically significant prostate cancer in a high-risk American population. All men who underwent prostate biopsy with the PRAP data registry since 1996 were included in the study. The probability of being diagnosed with any prostate cancer and significant prostate cancer (Gleason score > 6) was calculated using the online versions of PCPT-RC 2.0 and ERSPC-RC 3/5. The performance of these calculators was compared using calibration (calibration plot and calibration-in-the-large), discrimination (comparing AUC curves using DeLong’s method) and decision curve analysis (to assess clinical utility). The calibration suggested that both risk calculators under-predicted the probability of any prostate cancer while PCPT-RC 2.0 over-predicted the probability of significant prostate cancer. Analysis of the AUC curves suggested that the PCPT-RC 2.0 (AUC: 0.59, 95% CI 0.52 to 0.66) showed a trend towards better discrimination for any prostate cancer as compared to ERSPC-RC 3/5 (AUC: 0.55, 95% CI 0.48-0.63, p= 0.3819). Similarly, PCPT-RC 2.0 (AUC: 0.71, 95% CI 0.61-0.82) showed a trend towards better discrimination for significant prostate cancer as compared to ERSPC-RC 3/5 (AUC: 0.63, 95% CI 0.51 to 0.75, p= 0.2335). PCPT-RC 2.0 proved to be clinically beneficial to predict significant prostate cancer in the range of lower prediction thresholds. These results suggest that the PCPT-RC 2.0 is superior to ERSPC-RC 3/5 in a high-risk American population. Aim 3 utilized a systematic review of the decision aids used to improve prostate cancer knowledge, improve risk perception, reduce confusion, involve in shared decision making or utilize PSA tests in men at high-risk of prostate cancer, defined as those with African descent or those with a family history of prostate cancer. Data was extracted by searching MEDLINE, CINAHL, EMBASE, and PsycINFO via Ovid and EBSCOhost. After screening titles and abstracts, the resulting full-text articles were assessed for inclusion and exclusion criteria. A data extraction table was created, and the methodological quality of the studies was assessed based on three criteria – randomization, double blinding and intention-to-treat analysis. Due to the clinical heterogeneity of the studies, a descriptive analysis of all the studies was conducted and tabulated. A total of 2605 articles were retrieved after literature search, of which 8 articles met the inclusion criteria and were included in the qualitative analysis. Of these 8 articles, 6 were targeted at those who were African American or those with an African descent and 2 articles included interventions targeted at those with a family history of prostate cancer. Majority of the studies targeted at African American men demonstrated an improvement in knowledge and reduction in decisional conflict in the intervention group compared to the control group. The two studies that included men with a family history of prostate cancer did not show any change in knowledge or decisional conflict in the intervention group compared to the comparison group. All studies were of low quality, except one which was medium quality. Thus, this review unveiled that tailored decision aids would be helpful in improving knowledge and reducing decisional conflict in African American men while decision aids designed for men with family history of prostate cancer would not significantly change prostate cancer knowledge or decisional conflict compared to the standard decision aid. Thus, one of the tailored decision aids can be used to help African American men improve their knowledge of prostate cancer and reduce decisional conflict, while the standard decision aid can be used in men with a family history of prostate cancer. These conclusions can be assimilated into the USPSTF recommended shared decision-making sessions between the patients and the physicians. / Epidemiology
42

Exploring User Requirements for the Design of an Electronic Patient Decision Aid for Guardians Making Treatment Decisions about Congenital Adrenal Hyperplasia

Tahir, Irtaza 11 1900 (has links)
Congenital Adrenal Hyperplasia (CAH) describes a set of autosomal recessive diseases which affect enzymes mediating steroid biochemistry in the adrenal glands. In chromosomal females, the excess androgens associated with CAH cause virilization. Females with a high degree of virilisation can undergo feminizing genitoplasty in infancy or later in life. Parents and guardians are the medical proxies for their infants and therefore make decisions on their behalf. However, decision-making about feminizing genitoplasty can be very difficult. One tool that could help in such a situation is an electronic patient decision aid (PtDA). However, a PtDA for feminizing genitoplasty does not exist and there is insufficient information in existing literature to inform its design and development. Thus, the objectives of this study were to: (1) Identify user requirements, (2) Develop specifications for the design and development of the PtDA, and (3) Understand the best way to implement and distribute the PtDA We used the persona-scenario methodology to acquire user-requirements. Persona-scenario sessions were conducted with four parents of children with CAH, two adult patients with CAH, and four healthcare practitioners. Participants created fictitious personas, and scenarios wherein their personas interacted with an idealized version of the PtDA. Transcripts of these persona-scenarios and facilitator notes were analyzed to identify user-requirements, which were interpreted into specifications. Participants provided user requirements about (1) information and decisional content in the PtDA, (2) proposed functionalities for the PtDA, (3) web usability, and (4) implementation context. Many of these requirements are supported by existing literature. The requirements identified in this project will inform the design and development of a PtDA for feminizing genitoplasty in patients with CAH. However, further research is necessary to understand how to best implement these requirements and to ensure that the gathered information is useful for a broad range of potential end users. / Thesis / Master of Science (MSc)
43

The application of PROMETHEE multi-criteria decision aid in financial decision making: case of distress prediction models evaluation

Mousavi, Mohammad M., Lin, J. 22 May 2020 (has links)
No / Conflicting rankings corresponding to alternative performance criteria and measures are mostly reported in the mono-criterion evaluation of competing distress prediction models (DPMs). To overcome this issue, this study extends the application of the expert system to corporate credit risk and distress prediction through proposing a Multi-criteria Decision Aid (MCDA), namely PROMETHEE II, which provides a multi-criteria evaluation of competing DPMs. In addition, using data on Chinese firms listed on Shanghai and Shenzhen stock exchanges, we perform an exhaustive comparative analysis of the most popular DPMs; namely, statistical, artificial intelligence and machine learning models under both mono-criterion and multi-criteria frameworks. Further, we address two prevailing research questions; namely, "which DPM performs better in predicting distress?" and "will training models with corporate governance indicators (CGIs) enhance the performance of models?”; and discuss our findings. Our multi-criteria ranking suggests that non-parametric DPMs outperform parametric ones, where random forest and bagging CART are among the best machine learning DPMs. Further, models fed with CGIs as features outperform those fed without CGIs.
44

Élaboration d’un modèle d’aide à la décision probabiliste pour l’évaluation de la performance des digues fluviales / Toward a probabilistic desicion aid model for assessment of levee's performance

Vuillet, Marc 30 November 2012 (has links)
Lors d'une crue, la défaillance d'une digue fluviale est susceptible d'avoir des conséquences en vies humaines et économiques lourdes. Dans ce contexte, la réglementation sur la sécurité des ouvrages hydrauliques a récemment été renforcée (décret du 11 décembre 2007). Elle impose dorénavant aux gestionnaires la réalisation de diagnostics périodiques et encourage l'évaluation probabiliste de la sécurité des digues. De part leur caractère à grand linéaire, la complexité de leurs mécanismes de rupture et la grande variété de données nécessaires à leur diagnostic, les digues induisent des problématiques de diagnostic particulières, nécessitant l'intervention d'un ingénieur expert. Celui-ci doit procéder à l'analyse spatiale de l'information, l'interprétation des données disponibles et la prise en compte de leurs incertitudes. Il procède ensuite, par expertise, à l'évaluation qualitative de la performance des ouvrages. L'objectif de la thèse est l'élaboration d'un modèle d'aide à la décision probabiliste pour l'évaluation de la performance des digues. Ce modèle a vocation à être utilisé par un ingénieur spécialisé, en situation de diagnostic rapide ou approfondi et en valorisant toutes les données disponibles. Le modèle apporte une aide à l'ingénieur pour : identifier les tronçons homogènes d'un linéaire de digue, évaluer la performance des ouvrages pour les différents mécanismes de ruptures et préciser les niveaux d'incertitudes des résultats produits en fonction de l'imperfection des données disponibles. Notre démarche de recherche comporte trois étapes :- le développement d'un modèle fonctionnel des mécanismes de rupture des digues, bâti à partir de méthodes issues de la Sûreté de Fonctionnement et du Raisonnement Qualitatif ;- le développement d'un modèle d'aide à la décision déterministe comprenant des indicateurs de performance pour chaque mécanisme de rupture des digues, suivant une méthode de construction de critères uniques de synthèse ;- le développement d'un modèle d'évaluation probabiliste de la performance incluant une méthode de prise en compte des incertitudes des informations d'entrée et des résultats du modèle dans le cadre des probabilités subjectives. Les résultats de nos recherches sont illustrés par des applications du modèle à des études de cas, sur des digues fluviales et torrentielles / Levee risk control is crucial, as flood defense failures may seriously affect human life or economics issues. The regulation in France relating to the safety of the hydraulic structures is recently evolved (decree of December 11, 2007) and henceforth envisages for levees the realization of regular diagnoses and studies of dangers and encourages a probabilistic evaluation of levees safety. A levee safety evaluation currently consists in appraising the work, including taking into account data stemming from various prior investigations: historical records, visual inspections, hydraulic modeling, geophysical explorations, geotechnical explorations, etc. Such investigations may be performed to a more or less comprehensive extent, according to the resources available. Levee diagnostic studies will first split the alignments into several homogenous construction and loading sections, then complete an expert quality assessment of their performance levels. The goal of our research is to develop a probabilistic model for performance assessment of river levees, for a quick or comprehensive diagnosis. The model give support for engineer and make possible to determine how much an evaluation may be trusted and will help decide which levee sections should be primarily subjected to action or investigations. This will also facilitate the decision making process regarding technical actions to be taken to improve a levee section performance. Our approach contains three main steps:- analyzing and modeling levees failure mechanisms with a functional model build up from risk analysis methods ;- construction of deterministic decision aid model including levees performance indicator, using unicriterion decision support methods ;- construction of a probabilistic-based model for evaluating levees performance. Such model taking into account the input data uncertainty by using subjective probabilities. Our research results are illustrated by model application on cases studies
45

Desenvolvimento de um modelo para avaliação de sites de comércio eletrônico utilizando a metodologia multicritério de apoio à decisão - MCDA / Development of a model for the evaluation of e-commerce sites using the Multicriteria Decision Aid methodology - MCDA

Silvestri, Luiz Antonio 05 March 2002 (has links)
Em meio às crises, surgem as ameaças e as oportunidades na Rede Mundial de Computadores. A Internet, âncora do Comércio Eletrônico, apresenta estas duas situações implícitas. Um grande acumulo de situações que se tornam ameaçadoras, as quais quando tratadas utilizando um embasamento científico, aprovado experimentalmente; são consideradas favoráveis, transformando-as em uma grande oportunidade de sucesso em uma próspera empresa, participante desse mundo virtual do comércio eletrônico na Internet. Com o intuito de colaborar com esta situação que envolve decisões importantes e estratégicas, grande volume de recursos, cujas soluções têm influência no futuro das organizações, esta dissertação propõe um modelo de avaliação para empresas de comércio eletrônico, visando sua melhoria contínua, através da aplicação recursiva desta avaliação. Tal modelo informado pelos juízos de valores daqueles responsáveis pelo site, objetiva identificar as limitações e potencialidades da empresa, diante dos cenários ameaçadores e oportunistas que se apresentam no momento de sua aplicação. Para a construção do modelo, foi eleita a metodologia Multicritério de Apoio à Decisão - MCDA, fundamentada cientificamente e com comprovada eficiência em aplicações práticas, considerada a mais adequada, por sua capacidade de gerar conhecimento aos participantes, através de um processo construtivista, e por sua capacidade de integrar tanto elementos objetivos quanto subjetivos. A partir da aplicação do modelo, será observado o perfil de desempenho de um site de comércio eletrônico mediante as ameaças e oportunidades existentes, sendo possível elaborar as recomendações e análises das ações, objetivando a melhoria da empresa de forma progressiva e contínua, servindo de referencial para aplicações futuras. / During times of crises, threats and opportunities will certainly arise in the computer World Wide Web. The Internet, an e-commerce anchor, presents both aforementioned situations. Many of these situations may become threatening, however, when treated by means of an experimentally proven scientific process, they can be changed into great opportunities for a company which participates in the Internet e-commerce virtual world. This situation involves important and strategic decisions, and a great amount of resources, which can lead to solutions that will have a great influence in the future of the organizations. In this way, this thesis proposes an evaluation model for e-commerce companies seeking continuous improvement by the recursive application of it. This evaluation model, that requires information provided by the site management, has as a goal to identify the company limitations and potentialities, in the presence of the threatening and opportunistic scenario existing at the moment of its application. For the development of the evaluation model, the MCDA - Multicriteria Decision Aid has been selected, as it is regarded as a scientifically well-founded methodology. Having its efficiency proven by practical applications, this methodology has been considered the most appropriate, because it generates knowledge to the participants, through a constructive process and for its capability of integrating both objective and subjective elements. Through the application of this model, the performance profile of the e-commerce sites will be observed, in face of the existing threats and opportunities. Thus, it becomes possible to elaborate the recommendations and analyses of actions to be taken, in order to improve the enterprise in a progressive and continuous way. Furthermore, this research can be used as a reference for future applications.
46

Elaboração de modelo para prospecção de cenários com auxilio multicritério a decisão: aplicação em empresa de serviços de engenharia do Estado do Rio de Janeiro

Vieira, Jose Artur Moraes 31 July 2017 (has links)
Submitted by Secretaria Pós de Produção (tpp@vm.uff.br) on 2017-08-01T01:26:36Z No. of bitstreams: 1 M2016 - Jose Artur Moraes Vieira.pdf: 2506150 bytes, checksum: 586cf2bf3d9b631d29846fc88be94f0a (MD5) / Made available in DSpace on 2017-08-01T01:26:36Z (GMT). No. of bitstreams: 1 M2016 - Jose Artur Moraes Vieira.pdf: 2506150 bytes, checksum: 586cf2bf3d9b631d29846fc88be94f0a (MD5) / As discussões recentes sugerem a utilização de recursos de maneira otimizada, dada a sua escassez cada vez mais presente, sejam ambientais, de prazo, financeiros, políticos ou legais. Tal fato torna a tomada de decisão e planejamento estratégico baseados em cenários futuros uma tarefa complexa, já que dispõe alternativas múltiplas e incertas. Este estudo, então, propõe um modelo para prospecção de cenários apoiado na abordagem de Auxílio Multicritério à Decisão (AMD), considerando obrigatoriamente, fatores políticos, econômicos, sociais, tecnológicos e ambientais, que possa ser utilizado como ferramenta para auxiliar no planejamento estratégico das empresas e aplica-lo em uma empresa de serviços de engenharia, localizada no Estado do Rio de Janeiro. A motivação do tema estudado está na possibilidade da aplicação de técnicas AMD no planejamento estratégico. Como resultado foi mostrada a utilidade do modelo proposto visto que possibilitou ao gestor analisar alternativas através da prospecção de futuros realizada. / Recent discussions suggest the use of resources optimally, given their scarcity increasingly present, whether environmental, term, financial, political or legal. This fact makes the decision-making and strategic planning based on future scenarios a complex task, as it has multiple and uncertain alternatives. This study then proposes a model for prospecting scenarios supported in Multicriteria Decision Aid (AMD), considering necessarily political, economic, social, technological and environmental factors, which can be used as an auxiliary tool in strategic planning companies and apply it in an engineering services company located in the state of Rio de Janeiro. The motivation of the subject studied is the possibility of applying AMD techniques in strategic planning. As a result was shown the usefulness of the proposed visa that enabled the manager to analyze alternatives over the prospect of future held model.
47

Traveler Centric Trip Planning: A situation-Aware System

Amar, Haitham January 2012 (has links)
Trip planning is a well cited problem for which various solutions have been reported in the literature. This problem has been typically addressed, to a large extent, as a shortest distance path planning problem. In some scenarios, the concept of shortest path is extended to reflect temporal objectives and/or constraints. This work takes an alternative perspective to the trip planning problem in the sense it being situation aware. Thus, allowing multitudes of traveler centric objectives and constraints, as well as aspects of the environment as they pertain to the trip and the traveler. The work in this thesis introduces TSADA (Traveler Situation Awareness and Decision Aid) system. TSADA is designed as a modular system that combines linguistic situation assessment with user-centric decision-making. The trip planning problem is modeled as a graph G. The objective is to find a route with the minimum cost. Both hard and soft objective/attributes are incorporated. Soft objective/attributes such as safety, speed and driving comfortability are described using a linguistic framework and processed using hierarchical fuzzy inference engine. A user centric situation assessment is used to compute feasible routes and map them into route recommendation scheme: recommended, marginally recommended, and not recommended. In this work, we introduce traveler's doctrines concept. This concept is proposed to make the process of situation assessment user centric by being driven by the doctrine that synthesizes the user's specific demands. Hard attributes/objectives, such as the time window and trip monitory allowances, are included in the process of determining the final decision about the trip. We present the underline mathematical formulation for this system and explain the working of the proposed system to achieve optimal performance. Results are introduced to show how the system performs under a wide range of scenarios. The thesis is concluded with a discussion on findings and recommendations for future work.
48

Development and evaluation of an automated path planning aid

Watts, Robert Michael 13 April 2010 (has links)
In the event of an onboard emergency, air transport pilots are remarkably adept at safely landing their aircraft. However, the tasks of selecting an alternate landing site and developing a safe path to land are very difficult in the high workload, high stress environment of a cockpit during an emergency. The purpose of this research was to develop an automated path planning aid which would assist the pilot in the completion of these tasks. A prototype was developed to test this concept experimentally. The experiment was also intended to gather further information about how pilots think about and accomplish this task as well as the best ways to assist them. In order to better understand the priorities and processes pilots use when dealing with emergency planning, a survey of airline pilots was conducted. The results of this survey highlighted the fact that each emergency is unique and has its own set of factors which are critically important. One factor which is important in many emergencies is the need to land quickly. The survey responses indicated that one of the most important characteristics of a useful tool is that it should provide pertinent information in an easy to use manner, and should not divert too much attention from their other tasks. A number of design goals drove the development of the prototype aid. First, the aid was to work within current aircraft, without requiring substantial redesign on the cockpit. Second, the aid was to help improve pilots' performance without increasing their workload. Finally, the aid was designed to assist pilots in obtaining and processing critical information which influences the site selection and path development tasks. One variation of the aid included a filter dial which allowed pilots to quickly reduce the number of options considered, another variation of the aid did not include such a dial. These two variations of the aid were tested in order to assess the impact of the addition of the filter dial to the system. Though many of the results did not prove to be statistically significant, they suggest that the addition of a filter dial improved the quality of the selected landing site; however, it also increased the time required for the selection. The results were obtained in both familiar and unfamiliar emergencies. The dial was shown to improve the time to complete the task in the case of unfamiliar emergencies. The experiment also compared an optimal ranking system to a non-optimal system, for which results showed no significant difference between the two. This may imply that while pilots did not tend to over rely on the ranking system, under-reliance may need to be addressed by training and a better understanding of the factors which impact the rankings. The participants found that the aid facilitates quick and easy access to critical information. The aid was also useful for processing this information by filtering out options which were inappropriate for a given scenario through the use of the filter dial. The participants also made recommendations about possible improvements which could be made to the system such as better filter settings which are more similar to the way that pilots think about their options.
49

Pastato statybos vietos parinkimo modeliavimas / The modelling of building lot selection

Laurinaitytė, Lina 30 September 2008 (has links)
Baigiamajame magistro darbe nagrinėjamos pastato statybos vietos parinkimo problemos, esama situacija Lietuvoje bei užsienyje. Aptarti metodai, kurie gali būti naudojami problemai spręsti. Išnagrinėti veiksniai, turintys įtakos parenkant pastato statybos vietą. Parinkti vietos parinkimą lemiantys rodikliai bei suformuoti jų nustatymo algoritmai. Remiantis turimais duomenimis sudarytas pastato statybos vietos parinkimo modelis. Taikant projektų daugiakriterinio kompleksinio proporcingo įvertinimo metodą parenkama daugiabučio gyvenamojo pastato statybos vieta. Išnagrinėjus teorinius ir praktinius pastato statybos vietos parinkimo aspektus, pateikiamos baigiamojo darbo išvados ir siūlymai. / The objective of final paper of master studies is to create the model of building lot selection. In this paper there are studying the problems of building lot selection, the present situation in Lithuania and abroad in this issue, giving the methods that could be used to solve these problems. Defining the factors, which influence the building lot selection, there are giving the rates that have influence on building lot selection, and there are giving the structure of estimation algorithms of these rates. According to the method of multi criteria integrated proportional evaluation of the projects, there are selected the building lot of the residential block of flats. Analyzing the academic and practical aspects of building lot selection, in the end of the work there are giving conclusions and proposals.
50

Traveler Centric Trip Planning: A situation-Aware System

Amar, Haitham January 2012 (has links)
Trip planning is a well cited problem for which various solutions have been reported in the literature. This problem has been typically addressed, to a large extent, as a shortest distance path planning problem. In some scenarios, the concept of shortest path is extended to reflect temporal objectives and/or constraints. This work takes an alternative perspective to the trip planning problem in the sense it being situation aware. Thus, allowing multitudes of traveler centric objectives and constraints, as well as aspects of the environment as they pertain to the trip and the traveler. The work in this thesis introduces TSADA (Traveler Situation Awareness and Decision Aid) system. TSADA is designed as a modular system that combines linguistic situation assessment with user-centric decision-making. The trip planning problem is modeled as a graph G. The objective is to find a route with the minimum cost. Both hard and soft objective/attributes are incorporated. Soft objective/attributes such as safety, speed and driving comfortability are described using a linguistic framework and processed using hierarchical fuzzy inference engine. A user centric situation assessment is used to compute feasible routes and map them into route recommendation scheme: recommended, marginally recommended, and not recommended. In this work, we introduce traveler's doctrines concept. This concept is proposed to make the process of situation assessment user centric by being driven by the doctrine that synthesizes the user's specific demands. Hard attributes/objectives, such as the time window and trip monitory allowances, are included in the process of determining the final decision about the trip. We present the underline mathematical formulation for this system and explain the working of the proposed system to achieve optimal performance. Results are introduced to show how the system performs under a wide range of scenarios. The thesis is concluded with a discussion on findings and recommendations for future work.

Page generated in 0.0951 seconds