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Estudo Comparativo de M?tricas de Pontua??o para Aprendizagem Estrutural de Redes BayesianasPifer, Aderson Cleber 30 August 2006 (has links)
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Previous issue date: 2006-08-30 / Bayesian networks are powerful tools as they represent probability distributions as graphs. They work with uncertainties of real systems. Since last decade there is a special interest in learning network structures from data. However learning the best network structure is a NP-Hard problem, so many heuristics algorithms to generate network structures from data were created. Many of these algorithms use score metrics to generate the network model. This thesis compare three of most used score metrics. The K-2 algorithm and two pattern benchmarks, ASIA and ALARM, were used to carry out the comparison. Results show that score metrics with hyperparameters that strength the tendency to select simpler network structures are better than score metrics with weaker tendency to select simpler network structures for both metrics (Heckerman-Geiger and modified MDL). Heckerman-Geiger Bayesian score metric works better than MDL with large datasets and MDL works better than Heckerman-Geiger with small datasets. The modified MDL gives similar results to Heckerman-Geiger for large datasets and close results to MDL for small datasets with stronger tendency to select simpler network structures / Redes Bayesianas s?o poderosas ferramentas de representa??o gr?fica de distribui??es de probabilidade. Tais redes manipulam incertezas existentes em sistemas do mundo real. A partir da ?ltima d?cada, especial interesse no aprendizado de sua estrutura a partir de um conjunto de dados. Entretanto, o aprendizado da estrutura ? um problema NP-Dif?cil, o que gerou a cria??o de Algoritmos heur?sticos de busca. Muitos desses Algoritmos s?o baseados em m?tricas de pontua??o para estimar o modelo. Este trabalho procura comparar tr?s das m?tricas mais utilizadas. Para gerar os resul tados foram utilizadas as redes ASIA e ALARM, que s?o dois dos benchmarks padr?es e o Algoritmo de busca K-2. A m?trica Bayesiana Heckerman-Geiger com hiperpar?metros que dificultam a gera??o de arestas apresentam melhores resultados que ?quelas que flexibilizam a gera??o de arestas, acontecendo o mesmo com a m?trica MDL modificada. A compara??o das duas m?tricas mostrou que a m?trica Bayesiana ? superior ? m?trica MDL com grandes conjuntos de dados e inferior, caso contr?rio. A modifica??o na m?trica MDL resultou em estruturas mais pr?ximas ?s apresentadas pela MDL para um conjunto reduzido de dados e mais pr?ximas ? Heckerman-Geiger para um grande conjunto de dados, quando seus par?metros restrigem a cria??o de arestas
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Incorporating human factors into process plant lifecycle: HF during design and operation of a process plantWidiputri, Diah Indriani 10 June 2011 (has links)
Major accidents in the process industries occurred mostly as an outcome of multiple failures in different safety barriers and their interrelation with unsafe acts by frontline operators. This has become the reason why safety analyses in terms of plant technical aspects cannot be performed independently from analysing human response to the changing technology. Unsafe acts and errors by operators must be seen as a symptom of system insufficiencies and underlying problems, rather than as the cause of an accident. With this paradigm, the need to optimally configure the system and the whole working condition to understand human’s limitation and requirements becomes very evident. It is too naive to desire that human operators make zero error by asking them to change their behaviour and to perfectly adapt to the system.
Human Factors (HF) attempts to cope with the need to understand the interrelation between human operators, the technology they are working with and the management system, with the aim to increase safety and efficiency. In achieving this goal, HF must be incorporated into the whole plant lifecycle, from the earliest design stage to plant operation and modifications. Moreover, HF analysis must comprise all kinds of operators’ activities and responsibilities in operating process plants, which can include manual works in field and supervisory control conducted remotely from a control centre/room.
This work has developed techniques that provide systematic way to incorporate HF into process plant lifecycle. The new HF analysis technique, PITOPA-Design, in a combination with the classic PITOPA, is applicable for an implementation during design and operation of a plant. With the awareness that safety analysis and HF cannot be performed separately, an interconnection with HAZOPs is made possible by means of this new technique. Moreover, to provide a systematic analysis of operators’ work in control room, an additional technique, the PITOPA-CR was also developed. This HF technique can as well be integrated into a general HF analysis both during design phase and plant operation. In addition to it, results coming from PITOPA-CR will provide information required to optimally configure control and alarm system, as well as the whole alarm management system to better understand the limitation and requirements of control room operators.
The structure of the development can be described as follows:
i) Development of HAZOPA (the Hazards and Operator Actions Analysis), which provides the interconnection between HF analysis and HAZOPs,
ii) Development of PITOPA-Design, a technique to incorporate HF consideration into design phase, which is differentiated into 3 stages to comprise the conceptual design, the basic engineering and the detail engineering phase,
iii) Development of PITOPA-CR, a technique for HF analysis in control room,
iv) Integration of PITOPA-CR into alarm management system, development of a technique for alarm prioritization.:ACKNOWLEDGEMENT i
ABSTRACT iii
ZUSAMMENFASSUNG iv
CONTENTS v
TABLE OF FIGURES viii
LIST OF TABLES x
NOMENCLATURE xi
ACRONYMS AND ABBREVIATIONS xii
CHAPTER 1 1
INTRODUCTION 1
1.1 Background 1
1.2 Objectives 2
1.3 Scope of Work 3
CHAPTER 2 5
THEORETICAL BACKGROUND 5
2.1 Fundamentals of Human Error 5
2.2 Human Factors (HF) 8
2.3 Motivations to Consider HF in Process Safety 9
2. 3. 1 Accidents that Address HF in Process Safety 11
2. 3. 2 Regulation and Legal Requirements 16
2. 3. 3 Business Value 19
2.4 Work of Operators in Complex Systems 19
2. 4. 1 Role of Operators in Complex Systems 20
2. 4. 2 Problems with Computerisation and Automation 24
2. 4. 3 Allocation of Functions and Levels of Automation 25
2.5 Performance Influencing Factors (PIFs) 27
2.6 Distributed Control System (DCS) and Alarm Systems 29
2. 6. 1 Alarm, Alarm System and Alarm Management 30
2. 6. 2 Most Common Alarm Problems 33
2. 6. 3 Improving Alarm Performance through Prioritization 34
2.7 Safety Analysis Methods 38
2.7.1 Qualitative Safety Analysis 39
2.7.2 Quantitative Safety Analysis 43
2.8 Mathematical Algorithms 44
2.8.1 Techniques for Multi-Criteria Decision Making (MCDM) 44
2.8.2 Classification Methods 47
CHAPTER 3 50
RECENT DEVELOPMENTS IN HF STUDIES 50
3. 1 Methods for HF analysis 50
A. Task Analysis 50
B. Techniques for Operators Actions Analysis 51
3. 2 Human Reliability Analyses (HRA) 52
3. 3 Consideration of Human Error in HAZOP 53
3. 4 HF in Process Plant Design 54
3. 5 HF in Alarm Management and DCS-Design 55
3. 6 The Need for Further Development of HF Methods 57
CHAPTER 4 58
MOTIVATION OF THE WORK 58
CHAPTER 5 61
PROCESS INDUSTRY TOOL FOR OPERATOR ACTIONS ANALYSIS (PITOPA) 61
5.1 The New Technique for Operator Actions Analysis (OAA) 64
5.2 Technique for Performance Influencing Factors (PIFs) Evaluation 65
5.3 Validation of PITOPA in the Process Industry 67
CHAPTER 6 71
EXTENDING HAZOP TO INTEGRATE HF INTO 71
GENERAL SAFETY ANALYSIS 71
6.1 Development of HAZOPA (The Hazard, Operability and Operator Actions Analysis) 72
6.2 Case Study 75
CHAPTER 7 85
APPROACH TO INCORPORATING HF CONSIDERATION 85
INTO PLANT DESIGN 85
7.1 Development of an Approach for HF Analysis in Design – The PITOPA-Design 85
7.1.1 HF Analysis in Conceptual Design Phase (HFAD–Conceptual) 88
7.1.2 HF Analysis in Basic Engineering (HFAD – Basic) 93
7.1.3 HF Analysis in Detail Engineering (HFAD-Detail) 107
7.2 Technique for HF-Design Parameters Evaluation 109
7.3 Intermediate Summary 114
CHAPTER 8 115
IMPLEMENTATION OF THE NEW PITOPA-DESIGN: 115
A CASE-STUDY 115
8.1 Conceptual Design 115
8.2 Basic Engineering 123
8.3 Detail Engineering 127
CHAPTER 9 132
APPROACH FOR IMPROVING OPERATOR PERFORMANCE 132
IN CONTROL ROOM 132
9.1 Performance Influencing Factors (PIFs) for Supervisory & Monitoring Tasks 134
9.2 Development of PITOPA-Control Room (PITOPA-CR) 140
9.2.1 Analysis of Normal Operation 142
9.2.2 Analysis of Abnormal Operation 150
9.3 Alarm Prioritization 156
9.3.1 A survey on Alarm Prioritization 156
9.3.2 Incorporation of CROAA into Alarm Prioritization 157
9.4 Intermediate Summary 165
CHAPTER 10 167
INCORPORATION OF OPERATOR ACTIONS ANALYSIS INTO ALARM MANAGEMENT 167
CHAPTER 11 171
RESULTS AND FUTURE WORKS 171
11. 1 Results 171
11. 2 Future Works 172
BIBLIOGRAPHY 174
APPENDIX A A-1
APPENDIX B B-1 / Schwere Unfälle in der Prozessindustrie erfolgen meist aus einem Zusammenspiel mehrerer verschiedener Fehler und der gleichzeitigen Wechselwirkung mit falschem menschlichem Handeln. Dabei sind diese Fehlhandlungen nicht als Unfallursache anzusehen, sondern sie resultieren aus Fehlern, die in dem System selbst zu finden sind. Aus diesem Grund kann bei der Sicherheitsanalyse die technische Analyse nicht unabhängig von der Betrachtung des Human Factors (HF) durchgeführt werden. Um eine Reduzierung der Fehlhandlungen zu erreichen, müssen das Anlagendesign, die Bedienbarkeit und die Arbeitsumgebung an die menschlichen Fähigkeiten angepasst werden.
Human Factors (HF) betrachtet die Interaktion zwischen menschlichen, technischen und organisatorischen Aspekten einer Anlage, mit dem Ziel die Sicherheit und Effektivität der Anlage zu optimieren. Dafür ist eine Einbindung von HF in den gesamten Lebenszyklus einer Anlage notwendig. So müssen HF- Analysen nicht nur während des Betriebs einer Anlage und bei Prozessmodifikationen durchgeführt werden, sondern auch während des gesamten Design- Prozesses, da gerade in den frühen Design-Phasen das Optimierungspotential besonders hoch ist. Eine solche Analysemethode muss alle Aufgaben eines Operators erfassen, so dass zwischen manueller Arbeit und der Arbeit in der Leitwarte unterschieden werden muss.
In dieser Arbeit wurden Analysentechniken entwickelt, die einen systematischen Ansatz zur Berücksichtigung des HF über den gesamten Lebenszyklus einer verfahrenstechnischen Anlage darstellen. Mit Hilfe der neuen Analysemethode, PITOPA-Design, können Untersuchungen sowohl während der Designphase als auch während des Betriebs einer Anlage durchgeführt werden. Da solche HF-Analyse immer in Verbindung mit einer klassischen Sicherheitsanalyse erfolgen muss, bindet die neue Methode die HAZOP-Analyse direkt ein.
Darüber hinaus wurde ein weiterer Ansatz für die Analyse von Operatorhandlungen in einer Messwartenarbeit entwickelt. Diese neue Analysentechnik, PITOPA-CR, bildet die Grundlage für Verbesserungen im Alarmsystem und wird in das Alarmmanagementsystem eingebunden.
Die Arbeit ist wie folgt strukturiert:
i) Entwicklung von HAZOPA (the Hazards and Operator Actions Analysis). Diese Methode stellt die Einbindung der HF-Analyse in HAZOP dar.
ii) Entwicklung von PITOPA-Design, zur HF-Analyse während des gesamten Designprozesses einer verfahrenstechnischen Anlage. Die Methode wurde in 3 Teile eingeteilt, um die drei Designsphasen Conceptual-, Basic-, und Detail-Design zu erfassen.
iii) Entwicklung von PITOPA-CR, zur HF-Analyse in der Messwarte.
iv) Einbindung von PITOPA-CR in das Alarmmanagementsystem und Entwicklung einer Technik zur Alarmpriorisierung.:ACKNOWLEDGEMENT i
ABSTRACT iii
ZUSAMMENFASSUNG iv
CONTENTS v
TABLE OF FIGURES viii
LIST OF TABLES x
NOMENCLATURE xi
ACRONYMS AND ABBREVIATIONS xii
CHAPTER 1 1
INTRODUCTION 1
1.1 Background 1
1.2 Objectives 2
1.3 Scope of Work 3
CHAPTER 2 5
THEORETICAL BACKGROUND 5
2.1 Fundamentals of Human Error 5
2.2 Human Factors (HF) 8
2.3 Motivations to Consider HF in Process Safety 9
2. 3. 1 Accidents that Address HF in Process Safety 11
2. 3. 2 Regulation and Legal Requirements 16
2. 3. 3 Business Value 19
2.4 Work of Operators in Complex Systems 19
2. 4. 1 Role of Operators in Complex Systems 20
2. 4. 2 Problems with Computerisation and Automation 24
2. 4. 3 Allocation of Functions and Levels of Automation 25
2.5 Performance Influencing Factors (PIFs) 27
2.6 Distributed Control System (DCS) and Alarm Systems 29
2. 6. 1 Alarm, Alarm System and Alarm Management 30
2. 6. 2 Most Common Alarm Problems 33
2. 6. 3 Improving Alarm Performance through Prioritization 34
2.7 Safety Analysis Methods 38
2.7.1 Qualitative Safety Analysis 39
2.7.2 Quantitative Safety Analysis 43
2.8 Mathematical Algorithms 44
2.8.1 Techniques for Multi-Criteria Decision Making (MCDM) 44
2.8.2 Classification Methods 47
CHAPTER 3 50
RECENT DEVELOPMENTS IN HF STUDIES 50
3. 1 Methods for HF analysis 50
A. Task Analysis 50
B. Techniques for Operators Actions Analysis 51
3. 2 Human Reliability Analyses (HRA) 52
3. 3 Consideration of Human Error in HAZOP 53
3. 4 HF in Process Plant Design 54
3. 5 HF in Alarm Management and DCS-Design 55
3. 6 The Need for Further Development of HF Methods 57
CHAPTER 4 58
MOTIVATION OF THE WORK 58
CHAPTER 5 61
PROCESS INDUSTRY TOOL FOR OPERATOR ACTIONS ANALYSIS (PITOPA) 61
5.1 The New Technique for Operator Actions Analysis (OAA) 64
5.2 Technique for Performance Influencing Factors (PIFs) Evaluation 65
5.3 Validation of PITOPA in the Process Industry 67
CHAPTER 6 71
EXTENDING HAZOP TO INTEGRATE HF INTO 71
GENERAL SAFETY ANALYSIS 71
6.1 Development of HAZOPA (The Hazard, Operability and Operator Actions Analysis) 72
6.2 Case Study 75
CHAPTER 7 85
APPROACH TO INCORPORATING HF CONSIDERATION 85
INTO PLANT DESIGN 85
7.1 Development of an Approach for HF Analysis in Design – The PITOPA-Design 85
7.1.1 HF Analysis in Conceptual Design Phase (HFAD–Conceptual) 88
7.1.2 HF Analysis in Basic Engineering (HFAD – Basic) 93
7.1.3 HF Analysis in Detail Engineering (HFAD-Detail) 107
7.2 Technique for HF-Design Parameters Evaluation 109
7.3 Intermediate Summary 114
CHAPTER 8 115
IMPLEMENTATION OF THE NEW PITOPA-DESIGN: 115
A CASE-STUDY 115
8.1 Conceptual Design 115
8.2 Basic Engineering 123
8.3 Detail Engineering 127
CHAPTER 9 132
APPROACH FOR IMPROVING OPERATOR PERFORMANCE 132
IN CONTROL ROOM 132
9.1 Performance Influencing Factors (PIFs) for Supervisory & Monitoring Tasks 134
9.2 Development of PITOPA-Control Room (PITOPA-CR) 140
9.2.1 Analysis of Normal Operation 142
9.2.2 Analysis of Abnormal Operation 150
9.3 Alarm Prioritization 156
9.3.1 A survey on Alarm Prioritization 156
9.3.2 Incorporation of CROAA into Alarm Prioritization 157
9.4 Intermediate Summary 165
CHAPTER 10 167
INCORPORATION OF OPERATOR ACTIONS ANALYSIS INTO ALARM MANAGEMENT 167
CHAPTER 11 171
RESULTS AND FUTURE WORKS 171
11. 1 Results 171
11. 2 Future Works 172
BIBLIOGRAPHY 174
APPENDIX A A-1
APPENDIX B B-1
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UHF-SAR and LIDAR Complementary Sensor Fusion for Unexploded Buried Munitions DetectionDepoy, Randy S., Jr. January 2012 (has links)
No description available.
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Mathematical models for ecoepidemiological interactions, with applications to herd behaviour and bovine tuberculosis, and evolutionary interactions of alarm calls / Modelos matemáticos para interações ecoepidemiológicas, com aplicações para o comportamento de manada e tuberculose bovina, e interações evolutivas de alarmesAssis, Luciana Mafalda Elias de 25 February 2019 (has links)
This thesis presents several nonlinear mathematical models applied to ecoepidemiology and evolution. A detailed study involving predator-prey type models considering an alternative resource for the predator was carried out, investigating the situation of infection in the prey and in the predator on separate models. Such study served as a theoretical contribution to the investigation of problems such as bovine tuberculosis in wild animal species presented in a specific model. We also developed models to explain the evolution of alarm calls in species of birds and mammals. The theoretical framework adopted for those evolution models is that of Population Ecology. The models were developed using Ordinary Diferential Equations (ODEs) to describe the population dynamics. The biological assumptions of the systems that we wanted to analyse were enumerated and explained / Esta tese apresenta vários modelos matemáticos não-lineares aplicados à ecopidemiologia e à evolução. Foi realizado um estudo detalhado envolvendo modelos do tipo predador-presa considerando um recurso alternativo para o predador, investigando situações de infecção na presa e no predador em modelos separados. Tal estudo, serviu de aporte teórico para a investigação de problemas como a tuberculose bovina em espécies de animais selvagens apresentado em um modelo específico. Também desenvolvemos modelos para explicar a evolução dos chamados de alarme em espécies de aves e mamíferos. O quadro teórico adotado para esses modelos de evolução é o da Ecologia de População. Nos modelos desenvolvidos usamos as Equações Diferenciais Ordinárias (EDOs) para descrever a dinâmica populacional. Consideramos pressupostos biológicos dos sistemas biológicos analisados
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Avaliação aprofundada da enurese e tratamento com alarme associado à uroterapia / Not informed by the authorPorto, Paula Ferreira Braga 05 February 2015 (has links)
Uma vez que atraves do uso do alarme de urina nem todas as criancas com enurese obtem os criterios definidos para o sucesso (14 noites secas consecutivas), buscou--se investigar procedimentos complementares para potencializar o seu efeito: a) o diario miccional, utilizado como um instrumento de avaliacao diagnostica da enurese e como uma medida dos efeitos de tratamentos e b) a uroterapia, que consiste de um conjunto de medidas comportamentais que tem como objetivo corrigir dificuldades provavelmente relacionadas a enurese nao corrigidas pelo uso do alarme. O diario miccional e o registro do volume de liquidos ingeridos e eliminados no periodo de dois dias pela crianca, que pode indicar, dentre outros padroes, urgencia miccional, hiperatividade detrusora, poliuria, bem como ingestao irregular de liquidos. As medidas comportamentais que compoe a uroterapia podem ser exemplificadas por: miccoes em horarios regulares; aumento da ingesta de liquidos e evitacao de irritantes vesicais. Neste estudo participaram 65 criancas e adolescentes com enurese distribuidas em dois grupos de tratamento. O primeiro grupo foi exposto a uroterapia e ao tratamento com alarme (grupo Uroterapia), enquanto o segundo grupo foi exposto somente ao tratamento com alarme (grupo Alarme). Por volta de 70% dos participantes de ambos os grupos obtiveram sucesso no tratamento, independentemente da realizacao da uroterapia. Os participantes do grupo Uroterapia apresentaram uma melhora mais acentuada no inicio do tratamento, mas esta nao se manteve como tendencia ao longo do tempo. Os participantes de ambos os grupos tiveram um aumento significativo da porcentagem da capacidade volumetrica da bexiga utilizada. Os participantes do grupo Uroterapia tiveram um aumento significativamente maior dos volumes de ingesta de liquidos e miccional / Not all children with enuresis reach 14 consecutive dry nights thought the use of the bell and pad alarm. That considered, we aimed to investigate additional procedures to enhance its success rate: a) the voiding diary, used as a diagnostic tool for evaluating enuresis and to measure overall treatments effects and b) urotherapy, consisting of a set of behavioral measures that aims at problems probably related to enuresis not corrected by the use of the bell and pad alarm. The voiding diary is a two--day record of fluid intake and micturition habits. It may indicate, among other patterns, urgency, detrusor overactivity, polyuria and irregular fluid intake. Urotherapy is composed of behavioral measures such: voiding at regular times; increased fluid intake; and avoidance of bladder irritants. 65 children and adolescents participated in this study. They were assigned to two treatment groups. The first group was exposed to urotherapy and to an alarm treatment (Urotherapy group), while the second was exposed only to an alarm treatment (Alarm group). Around 70% of participants became dry, regardless of the group they were assigned to. Participants from the Urotherapy group showed a more marked improvement early in treatment, but this trend was not maintained over time. Participants from both groups had a significant increase in the percentage of volumetric bladder capacity used and participants from the Urotherapy group had a significantly greater increase of fluid intake and voided volume
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Charge-flow structures as polymeric early-warning fire-alarm devices.Sechen, Carl Matthew January 1977 (has links)
Thesis. 1977. M.S.--Massachusetts Institute of Technology. Dept. of Electrical Engineering and Computer Science. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING. / Includes bibliographical references. / M.S.
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Acompanhamento à distância do tratamento com alarme para enurese: efeitos dos problemas de comportamentoFerrari, Rafaela Almeida 12 March 2014 (has links)
A enurese é uma condição caracterizada pela eliminação de urina durante o sono, em crianças com mais de cinco anos, em função da dificuldade de acordar associada à baixa produção do hormônio vasopressina ou à instabilidade da bexiga, sem outra condição clínica que explique os episódios de molhar a cama. A intervenção comportamental com alarme é a mais recomendada pela literatura para a cura da enurese. O acompanhamento do uso do alarme pode ser realizado através de contatos telefônicos, em que são investigados pontos chave do procedimento a ser realizado em casa pelas famílias. Uma pesquisa verificou que o acompanhamento telefônico é uma alternativa eficaz para a população que faz uso do alarme de urina para enurese, mas sem obter clareza na questão da sua validade para crianças com escores clínicos de problemas de comportamento. O presente estudo teve como objetivo geral comparar a eficácia do tratamento para enurese entre dois grupos de participantes que receberam acompanhamento telefônico, sendo previamente classificados pelos pais de duas maneiras: um com índices clínicos de problemas de comportamento e outro sem tais índices. Como objetivos específicos: (1) classificar as crianças quanto aos problemas de comportamento a partir de observação feita por uma pesquisadora; (2) verificar a eficácia do tratamento para crianças com e sem problemas de comportamento, a partir da avaliação da pesquisadora; (3) Verificar a evolução dos problemas de comportamento comparando escores pré e pós tratamento a partir da avaliação dos pais (4) comparar o nível de autoconceito reportado pela criança antes e após a intervenção (5) verificar possíveis correlações entre nível de autoconceito e o resultado do tratamento. Participaram do estudo 31 crianças com idades entre seis a 11 anos, (média=8,3, DP=1,3), sendo 15 do sexo masculino e 16 do sexo feminino e seus pais. Para a inclusão da criança no tratamento, o diagnóstico de enurese foi obtido através do Formulário de Avaliação de Enurese. Para a avaliação dos problemas de comportamento foram aplicados o Inventário de Comportamento para Crianças e Adolescentes (CBCL), destinado aos pais e o Inventário de Observação Direta (DOF), instrumento que permite ao pesquisador observar e qualificar o comportamento infantil em escalas semelhantes às obtidas pelo preenchimento do CBCL durante atividades recreativas. Este último instrumento foi preenchido por uma pesquisadora vinculada ao Projeto Enurese. Para mensurar o autoconceito foi utilizado a Escala de Autoconceito Infanto-Juvenil. Setenta e um por cento dos participantes, independente do grupo (clínico ou não clinico) ao qual pertenciam obtiveram sucesso no tratamento, não havendo correlação entre os problemas de comportamento e os resultados do tratamento. A única variável 8 relacionada com o sucesso foi a menor frequência de episódios de molhadas antes do tratamento. As avaliações feitas pelos pais e pela pesquisadora em relação aos problemas de comportamento apresentaram um ligeiro grau de concordância (57,2%). Conforme esperado, o grupo das crianças que obteve sucesso no tratamento apresentou melhora nos índices de problemas de comportamento totais e autoconceito pessoal e social quando comparado ao daquelas que não obtiveram sucesso / Enuresis is a condition defined by urine loss during sleep due to the incapacity to wake up in response to the full bladder signals associated to a lack of vasopressin hormone or dysfunctional bladder activity, when the child is at least five years-old and has no other condition that explains bedwetting. Behavioral intervention with alarm is one of the most effective ways to cure enuresis. One method to monitor the alarm use by the families is periodic phone calls, in which the researcher checks if the treatment procedure is being correctly done. A past research concluded that monitoring the intervention by phone is a effective alternative for the treatment, but it was unclear if children with clinical levels of behavioral problems would benefit of it. This study aimed to compare the treatment efficacy with two groups receiving alarm treatment with phone follow up, one group with clinical levels of behavioral problems and the other without it, according to the parents\' view. Specific objectives were: (1) to use an alternative method to assess behavioral problems, according to a researcher\'s point of view; (2) to verify treatment efficacy for children with and without clinical levels of behavioral problems according to the researcher\'s point of view; (3) to compare behavioral problems levels before and after treatment, according to the parents\' point of view; (4) to compare children\'s self-concept levels before and after treatment; and (5) to investigate correlations between self-concept levels and treatment result. Thirty-one children aged 6 to 11 (mean=8,3, SD=1,3) were included in the study. Fifteen were male and 16 were females. To assess enuresis the Enuresis Assessment Form was used; to assess behavioral problems, the Child Behavior Checklist (CBCL) and the Direct Observation Form (DOF) were applied, the first instrument was filled up by the parents at home and the second by a researcher during recreational activities. The Child Self-Concept Scale was used to assess participants\' self-concept. Seventy-one percent of the children reached the criterion for treatment success. There was no influence of behavioral problems in the treatment result. A higher bedwetting frequency prior to treatment was the only variable related to a better treatment result. The comparison between the parents and the researchers evaluation about the behavioral problems showed a moderated level of agreement (57,2%). As expected, children who were successful in the treatment showed a significantly higher improvement in total behavioral problems levels and personal and social self-concept, when compared to those who did not had success
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Análise de risco para embarcações com sistemas de alarmes com foco nos fatores humanos e organizacionais. / Risk analysis for ships with alarm systems, focusing on human and organizational factors.Barbarini, Luiz Henrique Maiorino 11 May 2012 (has links)
Este trabalho apresenta uma proposta de modelo de análise de risco para embarcações, incorporando em sua formulação a influência das interações entre os sistemas de alarmes e os fatores humanos e organizacionais presentes a bordo. De acordo com estatísticas de sociedades classificadoras, o homem é o maior responsável por acidentes marítimos, e, desta forma, é um dos principais componentes da segurança de uma embarcação. A relevância do elemento humano se dá pelo fato de que ações e decisões humanas estão relacionadas tanto à causa, quanto à prevenção de acidentes. O sistema de alarmes é um equipamento de segurança obrigatório, e com direta participação na dinâmica de um acidente, fornecendo informação para a tomada de decisão das ações por parte da tripulação na resolução do problema. O estudo da interação entre este equipamento e o elemento humano a bordo permite a gestores e armadores elaborar diretrizes para investimentos em sistemas de segurança e políticas que influenciam o desempenho humano, e, portanto, a segurança a bordo. O modelo proposto, inspirado em relatório de acidentes marítimos, tem como ponto de partida uma estrutura sequencial do acidente e leva em consideração uma sucessão usual e simplificada dos eventos ocorridos, iniciando a partir de uma falha no sistema físico. O elemento humano, então, é incorporado à análise de risco através das técnicas de análise de confiabilidade humana, as quais têm como princípio a visão do homem como mais um componente do sistema, ou o liveware interagindo com software e hardware. Sob este ponto de vista, uma abordagem sócio-técnica é aplicada, ou seja, considera-se que um navio é composto não apenas de sua estrutura e máquinas, mas também de toda a tripulação. Com o objetivo de exemplificar passos e hipóteses de uma aplicação do modelo proposto, é apresentada a aplicação ao caso do acidente da embarcação Maersk Doha, ocorrido em outubro de 2006 nos Estados Unidos, cujo relatório de investigação do acidente é de acesso público via Internet, no site da Marine Accident Investigation Branch MAIB. / This work presents a risk analysis model for ships, focusing on the scenarios where the crew interacts with the alarm and monitoring system. According to statistics of classification societies, humans are largely responsible for accidents on board and, therefore, are considered a major component of the safety of vessels. The relevance of the human element is given by the fact that human decisions and actions are related to the cause of accidents, either being the direct causative factor of failure or influencing the probability of failure, and the prevention of accidents or mitigation of the consequences. The alarm system is a mandatory component of certified vessels, with direct participation in an accident. It supplies information for the decision making process of the crew, considering their actions to recover the system. The study of the interactions between this automation equipment and the human element on board provides guidelines to managers and owners to invest in proper security systems and policies that influence human behavior, and therefore the safety on board. The model, inspired in accident reports, has as starting point a sequential structure of the accident, and takes into account a typical and simplified sequence of events, starting from a failure in the physical system. The human element is incorporated into the risk analysis through techniques of human reliability analysis, which place man as another component of the system, or the \"liveware\" interacting with software and hardware. From this point of view, a socio-technical approach is applied, considering that a ship is composed of not only its structure and machinery, but also of the entire crew. In order to illustrate the steps and assumptions to be done by an analyst applying the proposed model, the accident of the vessel Maersk Doha, occurred in October of 2006 in the United States, is analyzed. The report on the investigation of this accident is public and accessible via the Internet site of the Marine Accident Investigation Branch MAIB.
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Fault Detection and Identification in Computer Networks: A soft Computing ApproachMohamed, Abduljalil January 2009 (has links)
Governmental and private institutions rely heavily on reliable computer networks for
their everyday business transactions. The downtime of their infrastructure networks may result in millions of dollars in cost. Fault management systems are used to keep today’s complex networks running without significant downtime cost, either by using active techniques or passive techniques. Active techniques impose excessive management traffic, whereas passive techniques often ignore uncertainty inherent in network alarms,leading to unreliable fault identification performance. In this research work, new
algorithms are proposed for both types of techniques so as address these handicaps.
Active techniques use probing technology so that the managed network can be tested periodically and suspected malfunctioning nodes can be effectively identified and
isolated. However, the diagnosing probes introduce extra management traffic and storage space. To address this issue, two new CSP (Constraint Satisfaction Problem)-based algorithms are proposed to minimize management traffic, while effectively maintain the same diagnostic power of the available probes. The first algorithm is based on the standard CSP formulation which aims at reducing the available dependency matrix significantly as means to reducing the number of probes. The obtained probe set is used for fault detection and fault identification. The second algorithm is a fuzzy CSP-based algorithm. This proposed algorithm is adaptive algorithm in the sense that an initial reduced fault detection probe set is utilized to determine the minimum set of probes used
for fault identification. Based on the extensive experiments conducted in this research both algorithms have demonstrated advantages over existing methods in terms of the overall management traffic needed to successfully monitor the targeted network system.
Passive techniques employ alarms emitted by network entities. However, the fault
evidence provided by these alarms can be ambiguous, inconsistent, incomplete, and
random. To address these limitations, alarms are correlated using a distributed Dempster-Shafer Evidence Theory (DSET) framework, in which the managed network is divided into a cluster of disjoint management domains. Each domain is assigned an Intelligent Agent for collecting and analyzing the alarms generated within that domain. These agents are coordinated by a single higher level entity, i.e., an agent manager that combines the partial views of these agents into a global one. Each agent employs DSET-based algorithm that utilizes the probabilistic knowledge encoded in the available fault propagation model to construct a local composite alarm. The Dempster‘s rule of combination is then used by the agent manager to correlate these local composite alarms.
Furthermore, an adaptive fuzzy DSET-based algorithm is proposed to utilize the fuzzy
information provided by the observed cluster of alarms so as to accurately identify the malfunctioning network entities. In this way, inconsistency among the alarms is removed by weighing each received alarm against the others, while randomness and ambiguity of the fault evidence are addressed within soft computing framework. The effectiveness of
this framework has been investigated based on extensive experiments.
The proposed fault management system is able to detect malfunctioning behavior
in the managed network with considerably less management traffic. Moreover, it
effectively manages the uncertainty property intrinsically contained in network alarms,thereby reducing its negative impact and significantly improving the overall performance of the fault management system.
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Fault Detection and Identification in Computer Networks: A soft Computing ApproachMohamed, Abduljalil January 2009 (has links)
Governmental and private institutions rely heavily on reliable computer networks for
their everyday business transactions. The downtime of their infrastructure networks may result in millions of dollars in cost. Fault management systems are used to keep today’s complex networks running without significant downtime cost, either by using active techniques or passive techniques. Active techniques impose excessive management traffic, whereas passive techniques often ignore uncertainty inherent in network alarms,leading to unreliable fault identification performance. In this research work, new
algorithms are proposed for both types of techniques so as address these handicaps.
Active techniques use probing technology so that the managed network can be tested periodically and suspected malfunctioning nodes can be effectively identified and
isolated. However, the diagnosing probes introduce extra management traffic and storage space. To address this issue, two new CSP (Constraint Satisfaction Problem)-based algorithms are proposed to minimize management traffic, while effectively maintain the same diagnostic power of the available probes. The first algorithm is based on the standard CSP formulation which aims at reducing the available dependency matrix significantly as means to reducing the number of probes. The obtained probe set is used for fault detection and fault identification. The second algorithm is a fuzzy CSP-based algorithm. This proposed algorithm is adaptive algorithm in the sense that an initial reduced fault detection probe set is utilized to determine the minimum set of probes used
for fault identification. Based on the extensive experiments conducted in this research both algorithms have demonstrated advantages over existing methods in terms of the overall management traffic needed to successfully monitor the targeted network system.
Passive techniques employ alarms emitted by network entities. However, the fault
evidence provided by these alarms can be ambiguous, inconsistent, incomplete, and
random. To address these limitations, alarms are correlated using a distributed Dempster-Shafer Evidence Theory (DSET) framework, in which the managed network is divided into a cluster of disjoint management domains. Each domain is assigned an Intelligent Agent for collecting and analyzing the alarms generated within that domain. These agents are coordinated by a single higher level entity, i.e., an agent manager that combines the partial views of these agents into a global one. Each agent employs DSET-based algorithm that utilizes the probabilistic knowledge encoded in the available fault propagation model to construct a local composite alarm. The Dempster‘s rule of combination is then used by the agent manager to correlate these local composite alarms.
Furthermore, an adaptive fuzzy DSET-based algorithm is proposed to utilize the fuzzy
information provided by the observed cluster of alarms so as to accurately identify the malfunctioning network entities. In this way, inconsistency among the alarms is removed by weighing each received alarm against the others, while randomness and ambiguity of the fault evidence are addressed within soft computing framework. The effectiveness of
this framework has been investigated based on extensive experiments.
The proposed fault management system is able to detect malfunctioning behavior
in the managed network with considerably less management traffic. Moreover, it
effectively manages the uncertainty property intrinsically contained in network alarms,thereby reducing its negative impact and significantly improving the overall performance of the fault management system.
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