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1	Análise de confiabilidade de estruturas com paredes portantes de concreto pré-moldado / Reliability analysis of structures with precast concrete loadbearing walls Cordeiro, Érico Souza Brito 22 March 2016 (has links) O método construtivo com painéis portantes de concreto é economicamente viável, porém relativamente novo no cenário nacional, sobretudo no caso dos pré-moldados. As incertezas referentes às peculiaridades desse método, bem como a nova norma brasileira de painéis pré-moldados, ainda em elaboração, vem a motivar uma análise probabilística dos critérios de projeto disponíveis. Utilizando-se a técnica da confiabilidade estrutural, é possível propagar as incertezas referentes às variáveis a uma resposta final no índice de confiabilidade, sendo um cálculo totalmente probabilístico. Neste trabalho, emprega-se tal técnica com informações estatísticas referentes a lajes de concreto moldadas in loco para verificar, de maneira mais verossímil, a segurança dos critérios de projeto impostos pelo Precast Concrete Institute Design Handbook - Precast and Prestressed Concrete - 7th Edition (2010) às fases transitórias (desforma, transporte e içamento) e pela Norma Brasileira ABNT NBR 6118: 2014 - Projeto de estruturas de concreto, à fase em uso. Prossegue-se a uma análise crítica dos resultados bem como sugestões para diminuir a variação dos resultados, sobretudo pela calibração de novos coeficientes parciais de segurança, processo para o qual este trabalho pode servir de base. / The shear wall building method is economicaly viable, but relatively new in the brazillian scene, that is specially true for precast members. The uncertainty pertaining this method, and the new brazillian design code for precast shear walls, still in development, serve as motivation for a probabilistic analysis of available project criteria. Using the structural reliability technique, it is possible to forward the variables uncertainties to a final answer in the form of the reliability index, being that this method is entirely probabilistic. In this study, this technique is used with statistical data pertaining cast-in-place concrete slabs to ascertain, with a higher degree of verisimilitude, the safety of the design criteria imposed by the Precast Concrete Institute Handbook - Precast and Prestressed Concrete - 7th Edition (2010) to the temporary states (stripping, transit and lifting) and by the Brazillian Code ABNT NBR 6118: 2014 - Concrete structures design, to the working state. The study then proceeds to a critical analysis of the results and to suggestions to reduce their variability, specially through calibration of new partial safety factors, a procedure to which this study might serve as a basis. Coeficientes de segurança Concreto pré-moldado Confiabilidade estrutural Loadbearing walls Paredes portantes Partial safety factors Precast concrete Structural reliability
2	Association Between Work-Related Safety and Work-Related Injuries Among Home Health Care Providers Abdulkhaleq, Sania Mohammed Saleh 01 January 2018 (has links) Home care nurses (HCNs) have reported a high rate of exposure to work-related injuries (WRIs). Nurses are challenged by the multidimensional problems associated with home care safety. These contextual risk factors increase the physical and social health problems of health care workers and of community suffering as a whole. This quantitative, cross-sectional study was designed to examine the relationship between the organization-related factors (ORFs) and the environment-related factors (ERFs) and their influences on safety behaviors (SBs) and the WRIs of HCNs. The PRECEDE framework was used to guide the study. Self-reported data were obtained from 74 home health care (HHC) nurses using the Safety Home Care Nursing questionnaire. A linear regression model was applied to determine the nature of the association between the independent variables and dependents variables. Findings showed the ORFs demonstrate a stronger effect on the SBs than the impact of the ERFs. The management commitment and the home-based care significantly affected the SBs. The supervisory support and safety access to a client's home were decreasing the WRIs. Therefore, the integration of efforts: The management and leadership of the health organization, the health care providers, and the clients' family would improve safety of HHC. This study is expected to help develop safety strategies for home care and thus attempt to minimize WRIs among HCNs. Nurses free of injuries are able to provide a quality of care and improve patients' health outcomes that in turn have an effect on reducing community suffering and financial costs. Environmental Safety Factors Home Health Care Safety Nursing Work Injuries Workplace Safety Nursing
3	Textilbeton Hegger, Josef, Will, Norbert, Schneider, Maike 05 December 2011 (has links) (PDF) Für die Anwendung des Verbundwerkstoffes „Textilbewehrter Beton“ sind die numerischen und experimentellen Grundlagenerkenntnisse zum Tragverhalten von Bauteilen in für die Baupraxis geeignete Nachweismodelle und Konstruktionsregeln zu überführen. Die aus dem Stahlbetonbau bekannten Ansätze müssen wegen der abweichenden Material- und Verbundeigenschaften für textilbewehrte Betonbauteile angepasst werden. Im Beitrag werden die grundlegenden Tragmechanismen textilbewehrter Elemente unter Zug-, Biege- und Querkraftbeanspruchung sowie punktförmiger Zugbeanspruchung beschrieben und die aus den Untersuchungsergebnissen abgeleiteten Nachweismodelle vorgestellt. Darauf aufbauend werden Sicherheitsbeiwerte für die textile Bewehrung ermittelt und die Berechnungsmodelle in ein Sicherheitskonzept eingebunden. Als einheitlicher Teilsicherheitsbeiwert für Textilbeton wird γtex = 1,5 vorgeschlagen. / For the application of the composite material Textile Reinforced Concrete (TRC) the numerical and experimental knowledge of the load bearing behaviour of construction elements has to be transferred into design models and construction rules applicable for the practice. Due to differences in the material and bond properties the design approach known for steel reinforced concrete has to be adjusted for textile reinforced concrete construction parts. In this paper the basic load-bearing mechanisms of textile reinforced concrete under tension, bending and shear loading as well as under concentrated tensile loading are described and empirically derived design models are presented. Based on the experimental results safety factors for the textile reinforcements are determined and the design models are integrated into an overall safety concept. A partial safety factor for textile reinforced concrete of γtex = 1,5 is recommended. Textilbeton Tragverhalten Bemessung Sicherheitskonzept Sicherheitsbeiwerte textile reinforced concrete load-bearing behavior design safety concept safety factors ddc:690 rvk:ZI 7100
4	Análise de confiabilidade de estruturas com paredes portantes de concreto pré-moldado / Reliability analysis of structures with precast concrete loadbearing walls Érico Souza Brito Cordeiro 22 March 2016 (has links) O método construtivo com painéis portantes de concreto é economicamente viável, porém relativamente novo no cenário nacional, sobretudo no caso dos pré-moldados. As incertezas referentes às peculiaridades desse método, bem como a nova norma brasileira de painéis pré-moldados, ainda em elaboração, vem a motivar uma análise probabilística dos critérios de projeto disponíveis. Utilizando-se a técnica da confiabilidade estrutural, é possível propagar as incertezas referentes às variáveis a uma resposta final no índice de confiabilidade, sendo um cálculo totalmente probabilístico. Neste trabalho, emprega-se tal técnica com informações estatísticas referentes a lajes de concreto moldadas in loco para verificar, de maneira mais verossímil, a segurança dos critérios de projeto impostos pelo Precast Concrete Institute Design Handbook - Precast and Prestressed Concrete - 7th Edition (2010) às fases transitórias (desforma, transporte e içamento) e pela Norma Brasileira ABNT NBR 6118: 2014 - Projeto de estruturas de concreto, à fase em uso. Prossegue-se a uma análise crítica dos resultados bem como sugestões para diminuir a variação dos resultados, sobretudo pela calibração de novos coeficientes parciais de segurança, processo para o qual este trabalho pode servir de base. / The shear wall building method is economicaly viable, but relatively new in the brazillian scene, that is specially true for precast members. The uncertainty pertaining this method, and the new brazillian design code for precast shear walls, still in development, serve as motivation for a probabilistic analysis of available project criteria. Using the structural reliability technique, it is possible to forward the variables uncertainties to a final answer in the form of the reliability index, being that this method is entirely probabilistic. In this study, this technique is used with statistical data pertaining cast-in-place concrete slabs to ascertain, with a higher degree of verisimilitude, the safety of the design criteria imposed by the Precast Concrete Institute Handbook - Precast and Prestressed Concrete - 7th Edition (2010) to the temporary states (stripping, transit and lifting) and by the Brazillian Code ABNT NBR 6118: 2014 - Concrete structures design, to the working state. The study then proceeds to a critical analysis of the results and to suggestions to reduce their variability, specially through calibration of new partial safety factors, a procedure to which this study might serve as a basis. Coeficientes de segurança Concreto pré-moldado Confiabilidade estrutural Paredes portantes Loadbearing walls Partial safety factors Precast concrete Structural reliability
5	Litteraturstudie om faktorer som påverkar familjehemsplacerade barns psykiska mående / Literature review on factors that affect children's psychic health placed in foster care Hyllman, Therese, Eriksson, Josefine January 2016 (has links) Background: Placed children have a higher risk of mental illness and negative development but it does not mean one can predict that it will go in a certain way for a certain child. Children belonging to a risk group can do well and vice versa, but it is the community and family care to balance the risk of a negative development Purpose: In this paper, the authors want to draw attention to the problems of children placed children's mental-being. The focus is on three different factors to get a broader picture of what may affect the mental health of foster children. Method: Descriptive literature review of scientific articles and literature. Results: The factors that form the basis of our study is continuous / discontinuous contact with the biological parents, interrupted foster placement and school outcomes for foster children. Theories selected to connect the various factors related theory and risk and protective factors. The results that have emerged show that foster children and young people feel worse than other children and young people who have not been children placed. School results are adversely affected by foster placement which has emerged in our study, and it is of great importance to the social, school, and family home cooperating to act against this. Conclusion: Reports and literature has been quite agree that foster children feel worse than other children in the community. The various factors that the study has highlighted, there was very little empirical data to collect, why did the authors broaden and think internationally. It would be desirable if it could be researched further in this area of research the more there are, the more knowledge is given to social workers who work with disadvantaged children in their everyday lives. Family home located children Mental health Connection theory Continuous/discontinuous connector Cancelled family home location School results Skolfam Risk and safety factors
6	Calibração baseada em confiabilidade dos coeficientes parciais de segurança das principais normas brasileiras de projeto estrutural / Reliability-based calibration of partial safety factors from main Brazilian codes Santiago, Wagner Carvalho 26 February 2019 (has links) Este trabalho apresenta uma calibração baseada em confiabilidade dos coeficientes parciais de segurança das normas brasileiras utilizadas no dimensionamento de estruturas metálicas e de concreto. O estudo tem como objetivo a determinação de coeficientes parciais de segurança que reflitam a realidade das estruturas brasileiras projetadas de acordo com as normas ABNT NBR 8681:2003 Ação e segurança nas estruturas, NBR 6118:2014 Projeto de estruturas de concreto e NBR 8800:2008 Projeto de estruturas de aço e de estruturas mistas de aço e concreto. O trabalho está fundamentado na teoria de confiabilidade estrutural, que permite uma representação explícita das incertezas envolvidas em termos das resistências e ações. O estudo aborda uma metodologia de calibração que envolve a obtenção de um conjunto de coeficientes parciais de segurança que minimiza as variações dos índices de confiabilidade das mais diversas estruturas projetadas segundo as normas de interesse, em relação ao índice de confiabilidade alvo utilizado na calibração. O trabalho revela que os coeficientes otimizados tendem a majorar as ações consideradas principais e a minorar as ações consideradas secundárias nas combinações normais de projeto. O estudo também mostra que os novos coeficientes conduzem a uma confiabilidade mais uniforme para as diferentes situações de projeto e tipologias de estruturas. / This work presents a reliability-based calibration of partial safety factors from Brazilian design codes used in the design of steel and concrete structures. The study aims to find partial safety factors that reflect the reality of Brazilian structures projected according to the codes NBR 8681:2003 Loads and safety in the structures, NBR 6118:2014 Design of concrete structures and NBR 8800:2008 Design of steel structures and mixed steel-concrete structures. The work is based on reliability theory, which allows an explicit representation of the uncertainties involved in terms of resistances and loads. The study deals with a calibration methodology that involves obtaining a set of partial safety factors that minimizes the variations of the reliability indices of the most diverse structures projected according to the codes of interest, in relation to the target reliability index used in the calibration. The work reveals that the optimized factors tend to increase the main loads and to reduce the secondary loads in the load combinations. The study also shows that the new factors lead to more uniform reliability for different design situations and structural typology. Calibração de norma Code calibration Coeficientes parciais de segurança Concrete structures Confiabilidade estrutural Estados limites Estruturas de concreto Estruturas metálicas Limits states Partial safety factors Steel structures Structural reliability
7	A framework for the deployment of traffic safety technologies in Abu Dhabi highways Al Junaibi, Musallem January 2016 (has links) There has been a good effort made in Abu Dhabi for the last couple of years between government stakeholders to develop a road safety strategy, define rules and responsibilities, and gain a fully coordinated and integrated framework to deal with road safety. According to my point of view, the challenges that might be seen as a problem for the future development of Abu Dhabi can be the management and the usage of traffic safety technologies to reduce serious road traffic accidents. This study focused on the relationship between the use of traffic safety technologies and serious road traffic accidents on Abu Dhabi Highways. The motivation for this research is to implement correctly the traffic safety technologies in Abu Dhabi highways as a part of the need to adopt plans, programmes, and preventive measures to reduce or prevent the occurrence of traffic accidents in order to ensure the safety of individuals and property, in addition to preserving the security of the state and its human and economic components. The overall approach to this study is a mixed methodology, which combines quantitative and qualitative methods. A questionnaire is one method used in this regard, and is designed to be quantitative. In the quantitative method, comparing statistics of fatalities and injuries before and after installation of the speed cameras is used. As a result of this study and by making the connectivity between reviewing the results and findings of the literature review, identifying the questionnaire results, and exploring the before and after statistics led to findings which were used to develop a decision support framework that can be used to advise the regional safety strategy to be sustainable. The design framework was also validated through Abu Dhabi highways by a panel of experts, which was carried out using the focus group method, which was qualitative in nature. It is recommended from this research to invest much in traffic safety technologies, focus more on driver support systems and rapid response systems, improve driver behaviour as a priority in Abu Dhabi highways using traffic safety technologies, and integrate the compatibility of all of the above through an integrated system and specific performance indicators that are measured and followed up on an ongoing basis, and supported by geographic information systems (GIS). 363.12
8	Textilbeton: Tragverhalten – Bemessung – Sicherheit Hegger, Josef, Will, Norbert, Schneider, Maike January 2011 (has links) Für die Anwendung des Verbundwerkstoffes „Textilbewehrter Beton“ sind die numerischen und experimentellen Grundlagenerkenntnisse zum Tragverhalten von Bauteilen in für die Baupraxis geeignete Nachweismodelle und Konstruktionsregeln zu überführen. Die aus dem Stahlbetonbau bekannten Ansätze müssen wegen der abweichenden Material- und Verbundeigenschaften für textilbewehrte Betonbauteile angepasst werden. Im Beitrag werden die grundlegenden Tragmechanismen textilbewehrter Elemente unter Zug-, Biege- und Querkraftbeanspruchung sowie punktförmiger Zugbeanspruchung beschrieben und die aus den Untersuchungsergebnissen abgeleiteten Nachweismodelle vorgestellt. Darauf aufbauend werden Sicherheitsbeiwerte für die textile Bewehrung ermittelt und die Berechnungsmodelle in ein Sicherheitskonzept eingebunden. Als einheitlicher Teilsicherheitsbeiwert für Textilbeton wird γtex = 1,5 vorgeschlagen. / For the application of the composite material Textile Reinforced Concrete (TRC) the numerical and experimental knowledge of the load bearing behaviour of construction elements has to be transferred into design models and construction rules applicable for the practice. Due to differences in the material and bond properties the design approach known for steel reinforced concrete has to be adjusted for textile reinforced concrete construction parts. In this paper the basic load-bearing mechanisms of textile reinforced concrete under tension, bending and shear loading as well as under concentrated tensile loading are described and empirically derived design models are presented. Based on the experimental results safety factors for the textile reinforcements are determined and the design models are integrated into an overall safety concept. A partial safety factor for textile reinforced concrete of γtex = 1,5 is recommended. info:eu-repo/classification/ddc/690 ddc:690
9	Existing codes and guidelines for durability design of FRP reinforcement Ur Rehman, Nazaib, Michler, Harald 10 November 2022 (has links) There are various approaches available for the durability design of non-metallic reinforcement in concrete, such are ACI 440.1R-15, BISE-99, CHBDC-07, NS3473-98, and JSCE-97.These available design approaches are very general and consolidate all effects into a single factor for each type of Fiber Reinforced Polymer (FRP) material depending on the type of fiber, which does not actually resemble the real concrete service life. Thus, more reliable design approaches are in need and have been developed in recent years which tried to simulate real-life conditions. They provide safety factors by not only considering the type of fiber, but also the moisture conditions, temperature conditions, diameter of the bar, and service life of the structure. Such design approaches need to be considered in the standards that can be applied in the concrete design context. This study was a part of my master’s thesis. info:eu-repo/classification/ddc/690 ddc:690
10	Development of Sensitive In Vitro Assays to Assess the Ocular Toxicity Potential of Chemicals and Ophthalmic Products McCanna, David January 2009 (has links) The utilization of in vitro tests with a tiered testing strategy for detection of mild ocular irritants can reduce the use of animals for testing, provide mechanistic data on toxic effects, and reduce the uncertainty associated with dose selection for clinical trials. The first section of this thesis describes how in vitro methods can be used to improve the prediction of the toxicity of chemicals and ophthalmic products. The proper utilization of in vitro methods can accurately predict toxic threshold levels and reduce animal use in product development. Sections two, three and four describe the development of new sensitive in vitro methods for predicting ocular toxicity. Maintaining the barrier function of the cornea is critical for the prevention of the penetration of infections microorganisms and irritating chemicals into the eye. Chapter 2 describes the development of a method for assessing the effects of chemicals on tight junctions using a human corneal epithelial and canine kidney epithelial cell line. In Chapter 3 a method that uses a primary organ culture for assessing single instillation and multiple instillation toxic effects is described. The ScanTox system was shown to be an ideal system to monitor the toxic effects over time as multiple readings can be taken of treated bovine lenses using the nondestructive method of assessing for the lens optical quality. Confirmations of toxic effects were made with the utilization of the viability dye alamarBlue. Chapter 4 describes the development of sensitive in vitro assays for detecting ocular toxicity by measuring the effects of chemicals on the mitochondrial integrity of bovine cornea, bovine lens epithelium and corneal epithelial cells, using fluorescent dyes. The goal of this research was to develop an in vitro test battery that can be used to accurately predict the ocular toxicity of new chemicals and ophthalmic formulations. By comparing the toxicity seen in vivo animals and humans with the toxicity response in these new in vitro methods, it was demonstrated that these in vitro methods can be utilized in a tiered testing strategy in the development of new chemicals and ophthalmic formulations. in vitro Alternative Methods alamarBlue rhodamine tight junctions bovine lens viability toxicity mitochondria mitochondria integrity benzalkonium chloride sodium dodecyl sulphate sodium lauryl sulfate scanning electron microscopy Draize Draize maximal average scores zonula occludens cosmetic directive PETA humane society animal league ICCVAM ECVAM JaCVAM BCOP bovine cornea ocular irritants ocular irritation ocular toxicity human corneal epithelial cells vitro confocal confocal microscopy metabolic activity optical quality reactive oxygen species contact lens contact lens care solutions barrier function microbial keratitis mulitipurpose solutions tight junction cell damage claudin ZO-1 occludin MDCK Madin Madin-Darby canine kidney cells cornea human cornea human corneal epithelium epithelial cell line human corneal epithelial cell line sodium fluorescein sodium fluorescein permeability fluorescein permeability ocular surface cell monolayer Araki-Sasaki cell physiology risk assessment safety assessment ScanTox scanning laser lens epithelium corneal cells in vitro model ophthalmic formulations multiple instillation back vertex animal testing rabbit testing alternatives to animal testing cultured bovine lens toxicity of chemicals irritation irritants laser scanner organ culture delayed toxicity toxins hydrogen peroxide cornea toxicity cornea toxicity models prediction of human toxicity no observable adverse effect level lowest observable adverse effect level NOAEL LOAEL toxicity thresholds safety factors cornea uncertainty factors preservatives disinfectants ophthalmic products preclinical preclinical testing epithelial barrier drug penetration clinical confocal microscopy animal rights rabbit cornea human cornea human clinical effects toxic animal rights activist sensitive measures toxic effect toxicity threshold agar overlay agar diffusion agar overlay method agar diffusion method cytochrome cytochrome c apoptosis necrotic apoptotic necrosis caspase rhodamine 123 resazuran resorufin cell death cell viability metabolic dye microsomal microsomal enzymes cytotoxicity cytotoxic cytotoxic effect MTT XTT WST-1 plasma membrane mitochondrial mitochondrial morphology ocular toxicity potential ocular toxicity human corneal epithelial cell line confocal analysis corneal epithelium cell fluorescence alamarBlue assay rhodamine dye animal welfare toxic injury degraded mitochondria epithelial monolayer disinfectants membrane integrity eye toxicity eye viability dye toxicity in humans human toxicity effects on the mitochondria mitochondrial toxicity in vitro battery in vitro test battery ophthalmic eye drop direct contact product safety cytotoxicity potential molecular molecular biology refine reduce replace sensitivity and relevance sensitivity relevance rabbit ocular irritation test product development cytotoxicity models cytotoxicity alternative methods replacements for animal testing three r's beagle tiered testing tiered testing strategy replacements animal testing mechanistic toxicity cornea mitochondria dose response threshold Vision Science and Biology

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