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A contribution to assess he structural vulnerability timber pavements

Teixeira, Marcos; Ferreira, Débora; Cunha, Victor; Feio, Artur; Lousada, José; Varum, Humberto; Guedes, Miranda; Pinto, Jorge
Fonte: INEGI Publicador: INEGI
Tipo: Conferência ou Objeto de Conferência
ENG
Relevância na Pesquisa
66.32%
In general, timber pavements are the main horizontal structural elements of the Portuguese traditional buildings. Since these types of buildings required to be preserved, the maintenance of timber pavements is crucial. However and unfortunately, the demolition of the interior of traditional buildings still is a current building option in rehabilitation processes. This building scenario is more expressive in private estate, in particular, in private dwellings. This option may be due to the lack of technical knowledge concerning timber pavements. Therefore, this paper intends to give a contribution in this matter by proposing an expedite methodology able to assess the structural vulnerability of these types of horizontal structural elements. Mapping the different structural vulnerability degrees of a traditional timber pavement may give guidance for maintenance, inspection and/or reinforcement design processes.

A contribution to assess the structural vulnerability timber pavements

Teixeira, Marcos; Ferreira, Débora; Cunha, Victor; Feio, Artur; Lousada, José; Varum, Humberto; Guedes, João; Pinto, Jorge
Fonte: INEGI Publicador: INEGI
Tipo: Conferência ou Objeto de Conferência
POR
Relevância na Pesquisa
46.24%
In general, timber pavements are the main horizontal structural elements of the Portuguese traditional buildings. Since these types of buildings required to be preserved, the maintenance of timber pavements is crucial. However and unfortunately, the demolition of the interior of traditional buildings still is a current building option in rehabilitation processes. This building scenario is more expressive in private estate, in particular, in private dwellings. This option may be due to the lack of technical knowledge concerning timber pavements. Therefore, this paper intends to give a contribution in this matter by proposing an expedite methodology able to assess the structural vulnerability of these types of horizontal structural elements. Mapping the different structural vulnerability degrees of a traditional timber pavement may give guidance for maintenance, inspection and/or reinforcement design processes.

Structural vulnerability of two traditional Portuguese timber structural systems

Murta, António; Pinto, Jorge; Varum, Humberto
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
56.29%
In general, the traditional Portuguese buildings show an undesirable deterioration level and, consequently, urgent rehabilitation processes are required. These buildings need maintenance and preservation because they are a valuable Portuguese heritage. Knowing and understanding these buildings is the first step for adequate rehabilitation processes. Usually, these buildings show the same pattern of pathologies and failure sequence. This research work is focused on the study of the roof timber structural systems of these buildings and intends to highlight these aspects. An expedite methodology of structural vulnerability assessment of the traditional Portuguese timber roof structures based on the structural vulnerability theory is presented. Real cases of traditional Portuguese timber roof structures are used. It was concluded that the trussed timber roof system seems less robust than the beamed system. (c) 2010 Elsevier Ltd. All rights reserved.

A theory of vulnerability of water pipe network (TVWPN)

Pinto, Jorge; Varum, Humberto; Bentes, Isabel; Agarwal, Jitendra
Fonte: Springer Publicador: Springer
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
46.07%
The main objective of this paper is to introduce the proposed theory of vulnerability of water pipe network (TVWPN) and, in particular, its theoretical concepts These concepts have a basis in the structural vulnerability theory (Agarwal et al, Civ Eng Environ Syst 18(2) 141-165, 2001a, J Struct Saf 23(3) 203-220, 2001b, Lu et al, Struct Eng 77(18) 17-23, 1999, Lu 1998, Pinto 2002, Pinto et al, J Struct Saf 24 107-122, 2002, Yu 1997) The fundamental contribution of this theory is to help design water pipe networks (WPN) more robust against damage to the pipelines This is achieved through an analysis of the form of the network The application of the TVWPN is presented through an example of a water pipe network

Seismic performance and strengthening of traditional masonry buildings in the city centre of Coimbra

Vicente, R.; Rodrigues, H.; Varum, H.
Fonte: Universidade de Aveiro Publicador: Universidade de Aveiro
Tipo: Conferência ou Objeto de Conferência
ENG
Relevância na Pesquisa
36.31%
The increasing concern and consequent appraisal on durability, conservation state and changeable use and function of old buildings in urban centres relies a great deal on the structural safety evaluation of vertical load capacity but also the capable resistance to horizontal forces. The need to assess seismic vulnerability, particularly of the traditional masonry buildings is a key issue. Particular attention has been put upon the building stock of the old city centre of Coimbra, mainly constituted by old masonry load-bearing buildings of significant architectural value. The evaluation of the seismic vulnerability of old buildings is essential in the definition of the strengthening needs and minimization of possible damages due to seismic actions, in safeguarding of built heritage or in the identification of critical buildings. This paper intends to contribute for the assessment of old buildings considering the local seismic risk. A three dimensional model was developed for an aggregate of four buildings. The finite element modelling of these buildings has intended to identify structural fragilities, help understand the damages detected in the existing structures (crack opening) and evaluate the global structural safety of this type of buildings. It will be presented the main results obtained in this study...

S. João de Loure Bridge: vulnerability assessment and study of a common strengthening solution

Varum, H.; Fernandes, C.
Fonte: Universidade de Aveiro Publicador: Universidade de Aveiro
Tipo: Conferência ou Objeto de Conferência
ENG
Relevância na Pesquisa
56.24%
This paper presents a structural vulnerability assessment of the steel bridge S. João de Loure. A structural model of the bridge was created and the influence of the joint’s stiffness on its structural response was evaluated using the structural analysis software SAP2000. Natural frequencies, axial forces and corresponding stress, and maximum mid-span deflection, were analyzed. A common strengthening solution with prestressing cables was studied intending to reduce the bridge’s mid-span deflection.

Structural vulnerability of Nepalese Pagoda temples

Shakya, M.; Varum, H.; Vicente, R.; Costa, A.
Fonte: Universidade de Aveiro Publicador: Universidade de Aveiro
Tipo: Conferência ou Objeto de Conferência
ENG
Relevância na Pesquisa
45.97%
Nepal is located in one of the most severe earthquake prone areas of the world, lying between collisions of Indian to the Eurasian plate, moving continuously, resulting in frequent devastating earthquakes within this region. Moreover, different authors refer mention that the accumulated slip deficit (central seismic gap) is likely to produce large earthquakes in the future. Also, the analysis of the available information of previous earthquakes indicates the potential damage that can occurs in unreinforced traditional masonry structures in future earthquakes. Most of the Nepalese pagoda temples were erected following very simple rules and construction details to accomplish with seismic resistance requirement, or even without any consideration for seismic resistance, during the period of Malla dynasty (1200-1768). Presently, conservation and restoration of ancient monuments are one of the major concerns in order to preserve our built heritage, transferring it to the future generations. The present paper is devoted to outline particular structural fragility characteristics in the historic Nepalese pagoda temples which affect their seismic performance. Moreover, based on the parametric analysis identified structural weaknesses/fragilities of pagoda topology...

Structural Vulnerability and Health: Latino Migrant Laborers in the United States

Quesada, James; Hart, Laurie K.; Bourgois, Philippe
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /07/2011 EN
Relevância na Pesquisa
46.12%
Latino immigrants in the United States constitute a paradigmatic case of a population group subject to structural violence. Their subordinated location in the global economy and their culturally depreciated status in the United States are exacerbated by legal persecution. Medical Anthropology Volume 30, issues 4 and 5, include a series of ethnographic analyses of the processes that render undocumented Latino immigrants structurally vulnerable to ill-health. We hope to extend the social science concept of ‘structural vulnerability’ to make it a useful tool for health care. Defined as a positionality that imposes physical/emotional suffering on specific population groups and individuals in patterned ways, structural vulnerability is a product of two complementary forces: (1) class-based economic exploitation and cultural, gender/sexual, and racialized discrimination; and (2) processes of symbolic violence and subjectivity formation that have increasingly legitimized punitive neoliberal discourses of individual unworthiness.

Sexual Health of Latino Migrant Day Labourers under Conditions of Structural Vulnerability

Organista, Kurt C.; Worby, Paula A.; Quesada, James; Arreola, Sonya G.; Kral, Alex H.; Khoury, Sahar
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
46.18%
The purpose of this paper is to explore the context of the sexual health of Latino migrant day labourers in the U.S.A., challenges to sexual health and ways of coping, with attention to conditions of structural vulnerability permeating the lives of this unique Latino population. Given the limited information about this topic and population, ethnographic research employing in-depth semi-structured interviews with 51 labourers, recruited through purposive sampling in the San Francisco Bay Area, was utilised. The sexual health aspirations of the men are deeply embedded in the core value and practice of Latino familismo or, in this case, the central goal of securing a family headed by men as providers and present husbands/fathers. However, such goals are frequently thwarted by the poverty engendering work and prolonged separations from home that characterise predominantly undocumented day labour in the U.S.A. Resulting goal frustration, combined with pent up sexual urges, often lead to sexual risk in spite of efforts to cope with challenges to sexual health. Unless community, state, and national level interventions are developed to mitigate the pronounced structural vulnerability of migrant day labourers, individual level interventions to promote sexual health...

Navigating the Risk Environment: Structural Vulnerability, Sex, and Reciprocity Among Women Who Use Meth

McKenna, Stacey A.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
46.09%
Drug users’ risky sexual practices contribute to their increased risk for contracting HIV and other sexually transmitted infections. Use of methamphetamine has been associated with a number of high-risk sexual practices such as frequent sexual contacts, multiple sex partners, unprotected sex, and exchange sex. The media construct women who use meth as engaging in exchange sex to support their drug habit. Despite an abundance of data on exchange sex among heroin and crack users that suggest the importance of examining these practices in context, they remain understudied among female methamphetamine users. This article draws on preliminary findings from ongoing ethnography with female meth users to highlight the risk environment(s) that contribute to structural vulnerability and shape behaviour. While their sexual practices may be deemed transactional and risky, understanding their embeddedness in structural context and networks of reciprocity is essential to understanding implications for policy and harm reduction.

Finding a Balance between Growth and Vulnerability Trade-Offs : Lessons from Emerging Europe and the CIS

Ghosh, Swati; Sugawara, Naotaka; Zalduendo, Juan
Fonte: Banco Mundial Publicador: Banco Mundial
Relevância na Pesquisa
36.29%
This paper examines the growth patterns of emerging Europe and the Commonwealth of Independent States (CIS) countries prior to the global financial crisis. The aim is to draw lessons on what policies can best position these countries going forward to enjoy growth without a buildup in macro and financial vulnerability. Cluster analysis is used to classify these countries across the growth and vulnerability dimensions; namely, a classification into low or high growth outcomes, each of which may occur with low or high vulnerability features. The vulnerability indicators used are multifaceted, covering both the domestic and the external dimensions that have been identified in previous studies as being good indicators of likelihood of crisis -- itself understood as multidimensional. Based on multinomial logit regressions, the initial conditions and the economic policies that might affect the probabilities of being in each of the four possible cluster combinations are examined. Many (if not most) of the countries in the sample experienced very large capital inflows relative to their gross domestic product prior to the crisis...

Seismic risk assessment and hazard mapping in Nepal

Chaulagain, Hemchandra; Rodrigues, Hugo; Silva, Vítor; Spacone, Enrico; Varum, Humberto
Fonte: Springer Publicador: Springer
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
46.18%
Seismic risk in the form of impending disaster has been seen from past records that moderate-to-large earthquakes have caused the loss of life and property in all parts of Nepal. Despite the availability of new data, and methodological improvements, the available seismic hazard map of Nepal is about two decades old. So an updated seismic hazard model at the country level is imperative and logical. The seismic hazard and risk model constitute important tools for framing public policies toward land-use planning, building regulations, insurance, and emergency preparedness. In fact, the reliable estimation of seismic hazard and risk eventually minimizes social and economic disruption caused by earthquakes. In this frame of reference, the seismic risk assessment at a country level is elementary in reducing potential losses stemming from future earthquakes. Thus, this study investigates structural vulnerability, seismic risk, and the resulting possible economic losses owing to future earthquakes in Nepal. To this end, seismic risk assessment in Nepal is done using an existing probabilistic seismic hazard, a newly developed structural vulnerability, and recently released exposure data. The OpenQuake-engine, the open-source platform for seismic hazard and risk assessment from the Global Earthquake Model initiative...

Human security and human rights under international law : reinforcing protection in the context of structural vulnerability

ESTRADA-TANCK, Dorothy
Fonte: Instituto Universitário Europeu Publicador: Instituto Universitário Europeu
Tipo: Tese de Doutorado
EN
Relevância na Pesquisa
46.18%
Examining Board: Professor Martin Scheinin, European University Institute (Supervisor) Professor. Ruth Rubio-Marin, European University Institute Professor Christine Chinkin, London School of Economics and Political Science Judge Antônio Augusto CançadoTrindade, International Court of Justice.; Defence date: 10 June 2013; Human security has been qualified as "the emerging paradigm for understanding global vulnerabilities". Articulated by UN and regional bodies over the last twenty years, its person-centred axis of freedom from fear, from want and to live in dignity and its protection and empowerment strategies, suggest communicating bridges with human rights law. However, this connection has seldom been explored at a deeper level that transcends human rights as discourse or token. This thesis analyses whether human security may provide tools for an expansive and integrated legal interpretation of international human rights, state and non-state obligations in the context of structural vulnerability; and whether a gendered and human rights-based approach can more accurately define the scope of human security and the types of violence and deprivation it considers. Thus, on the basis of an initial interdisciplinary research, this thesis maps and critically evaluates the expressions of human security/human rights interaction in international law...

Self-assessed oral health, cognitive vulnerability and dental anxiety in children: Testing a mediational model

Carrillo-Diaz, M.; Crego, A.; Armfield, J.; Romero-Maroto, M.
Fonte: Blackwell Munksgaard Publicador: Blackwell Munksgaard
Tipo: Artigo de Revista Científica
Publicado em //2012 EN
Relevância na Pesquisa
36.28%
OBJECTIVE: To explain the association between children's self-perceived oral health status and dental anxiety, by considering their levels of cognitive vulnerability. METHODS: Participants were 161 children (47.8% female; mean age = 11.93 years) who filled in a questionnaire comprising self-assessed oral health-related status, dental treatment-related cognitive vulnerability and dental anxiety measures. Gender, age and number of decayed, missing and filled permanent teeth were controlled for. Bivariate correlations, hierarchical regression analyses and structural equation modelling were conducted to test the hypotheses. RESULTS: Subjective oral health status, cognitive vulnerability variables and dental anxiety were strongly correlated. Regression and structural models testing the mediating effects of cognitive vulnerability variables on the relationship between perceived oral health and dental anxiety were supported. CONCLUSIONS: The activation of the cognitive vulnerability schema, as a mediating variable, is a mechanism by means of which children's self-perceptions of a poor oral health might lead to dental anxiety. Both components of vulnerability analysed (threat and disgust) contribute decisively to this potential process.; María Carrillo-Díaz...

The East Asian currency crises: lessons for an early warning system

Jotzo, Frank
Fonte: Universidade Nacional da Austrália Publicador: Universidade Nacional da Austrália
Tipo: Working/Technical Paper Formato: 303887 bytes; 172543 bytes; application/pdf; application/pdf
EN_AU
Relevância na Pesquisa
46.18%
Is it possible to devise a functioning early warning system for currency crises, and is there a role for the analysis of indicators beyond economic fundamentals? In light of the East Asian crisis, the issue is examined both theoretically and empirically. An analytical framework to detect macroeconomic and structural vulnerability as well as changes in the perception of fundamentals is developed, and a range of leading indicators explored. An exemplary early warning system which includes investors' sentiments is applied retrospectively in case studies of the crises in Indonesia and Thailand in 1997, Mexico 1994 and three other Latin American episodes.

The paper argues that the monitoring of market sentiments has a place along with the analysis of economic fundamentals, structural and political factors. Particularly in the recent East Asian experience, a sudden and dramatic change in the perception of economic fundamentals and expectations regarding future developments was the driving force behind the crisis. A range of promising indicators are identified, some using readily available quantitative data. The challenge lies in the exploration of relevant information outside the traditional realm of economics and the construction of quantifiable indices. The importance of sudden changes in expectations...

‘Boots for my Sancho’: structural vulnerability among Latin American day labourers in Berkeley, California

Ordóñez, Juan Thomas
Fonte: Universidade do Rosário Publicador: Universidade do Rosário
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/acceptedVersion Formato: application/pdf
Publicado em //2012 ENG
Relevância na Pesquisa
56.12%
This paper addresses the structural vulnerability of Latin American undocumented day labourers in Northern California, as it is expressed in conversations on street corners where they wait for work. The intimate aspects of migrant experience become exemplified in jokes about the Sancho – a hypothetical character who has moved in on a day labourer's family and who enjoys the money he sends home. Joking turns to more serious topics of nostalgia and tensions with family far away, elements that come together with the fears and threats of labour on the corner and affect the way day labourers see themselves. Sexuality is rearticulated in the absence of women and masculinity becomes enmeshed in the contingencies of unregulated work and long-term separation from the people the men support. Together, these elements result in the articulation of threat to the immigrant body itself, which is exemplified by anxieties over homosexual propositions on the corner. Cet article aborde la vulnérabilité structurelle des travailleurs journaliers latino-américains sans papiers dans le Nord de la Californie, telle qu'ils l'expriment dans leurs conversations en attendant du travail aux coins des rues. Les aspects intimes de l'expérience de la migration sont exemplifiés à travers des blagues sur le Sancho – un personnage hypothétique qui...

Attack structural vulnerability of power grids: A hybrid approach based on complex networks

Chen, Guo; Dong, Zhao Yang; Hill, David; Zhang, Guohua; Hua, Ke Qian
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
46.03%
Power grids have been studied as a typical example of real-world complex networks. Different from previous methods, this paper proposes a hybrid approach for structural vulnerability analysis of power transmission networks, in which a DC power flow model

An improved model for structural vulnerability analysis of power networks

Chen, Guo; Dong, Zhao Yang; Hill, David; Zhang, Guohua
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
46.03%
Electric power networks have been studied as a typical example of real-world complex networks. Traditional models for structural vulnerability analysis appear to be all based on physical topological structure. In this paper, we depict a typical power netw

Structural Vulnerability of Power Grids to Disasters: Bounds, Adversarial Attacks and Reinforcement

Deka, Deepjyoti; Vishwanath, Sriram
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 24/09/2015
Relevância na Pesquisa
46.21%
Natural Disasters like hurricanes, floods or earthquakes can damage power grid devices and create cascading blackouts and islands. The nature of failure propagation and extent of damage is dependent on the structural features of the grid, which is different from that of random networks. This paper analyzes the structural vulnerability of real power grids to impending disasters and presents intuitive graphical metrics to quantify the extent of damage. Two improved graph eigen-value based bounds on the grid vulnerability are developed and demonstrated through simulations of failure propagation on IEEE test cases and real networks. Finally this paper studies adversarial attacks aimed at weakening the grid's structural resilience and presents two approximate schemes to determine the critical transmission lines that may be attacked to minimize grid resilience. The framework can be also be used to design protection schemes to secure the grid against such adversarial attacks. Simulations on power networks are used to compare the performance of the attack schemes in reducing grid resilience.; Comment: 9 pages, 11 figures

Representation of electric power systems by complex networks with applications to risk vulnerability assessment

Correa-Henao,Gabriel Jaime; Yusta-Loyo,José María
Fonte: DYNA Publicador: DYNA
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/08/2015 EN
Relevância na Pesquisa
46.07%
The occurrence of impact events (e.g. blackouts with vast geographic coverage) into electrical critic infrastructure systems usually require the analysis of cascade failure root causes through the conduction of structural vulnerability studies, with well-defined methodologies that may guide decision-making for the implementation of prevention actions and for operation recovery of the power system (e.g. N-1 and N-t contingency studies). This technical contribution provides some alternative techniques based upon complex networks and graph theory, which in the last few years, have been proposed as useful methodologies for analysis of physical behavior of electric power systems. Vulnerability assessment is achieved by testing their performance into random risks and deliberate attack threat scenarios. Results shown in this proposal lead to conclusions on the use of complex networks for contingency analysis by means of studies of those events that result in cascade failures and consumer disconnections.