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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
171

The effects of performance based tasks on student understanding of science concepts and science process skills

Gill, Clara Joanne Schneberger 01 July 2003 (has links)
No description available.
172

États limites de piliers de ponts en béton armés de cerces avec recouvrement à la base

Zuluaga Rubio, Luis Felipe January 2015 (has links)
Résumé : Plusieurs tremblements de terre passés ont montré que face aux séismes, les ponts peuvent être les points faibles d’un réseau de transport. Néanmoins, les retours des expériences postsismiques ainsi que les études théoriques et expérimentales effectuées par les chercheurs et les ingénieurs de la pratique ont permis de faire évoluer les règles de l'art relatives au comportement sismique des ponts. Un des résultats de cette évolution est le dimensionnement basé sur la performance sismique (DBPS). En bref, le DBPS tente de concevoir des structures qui atteindront un état limite de performance déterminé lorsqu’ils sont soumis à un séisme d’une intensité donné. Toutefois, dans l'optique du DBPS, il est primordial de situer les états limites des composantes principales des ponts, principalement des piliers, de manière mesurable plutôt que phénoménologique. Lors du développement de courbes de fragilité des ponts au Québec, il est apparu que les états limites des piliers de ponts n'étaient pas clairement définis. Un programme de recherche expérimental a donc été conçu pour déterminer les états limites des piliers de pont en béton armé. Le projet comprend l’essai d’un poteau en béton armé à échelle réelle soumis à des cycles de chargement latéral en plus d’une charge axiale constante représentative du niveau de chargement réel. Le poteau reproduit les propriétés exactes des piliers du pont Chemin des Dalles (Trois-Rivières, Québec). Ce projet de recherche vise à améliorer l’évaluation de la fragilité sismique des ponts actuels du réseau routier québécois et à optimiser le dimensionnement sismique des futures structures selon l’approche basée sur la performance sismique. En particulier, le projet cherche à répondre aux incertitudes importantes qui subsistent sur la description quantitative des états limites des piliers de ponts en béton armé, particulièrement au niveau des déformations associées. / Abstract : Several past earthquakes have shown that bridges can be the weak points of a transport network. Nevertheless, returns of the post-seismic experiences as well as theoretical and experimental studies made by researchers and practice engineers allowed the art rules evolution related to the seismic behavior of bridges. One result of this evolution is the seismic performance based design (DBPS). In brief, the DBPS tries to design structures which will reach a certain limit state of performance when they are submitted to an earthquake of a given intensity. However, in the optics of the DBPS, it is essential to define the limit states of the main components of bridges, mainly for columns, in a measurable way rather than phenomenological. During the development of the fragility curves of bridges in Québec, it seemed that the limit states of the bridges columns were not clearly defined. An experimental research program was thus designed to determine the limit states of the reinforced concrete bridge columns. The project includes the testing of a large-scale reinforced concrete bridge column submitted to lateral cycles load in addition to a constant axial load which represented the real dead load level. The column reproduces the exact properties of the Chemin des Dalles bridge columns (Trois-Rivières, Québec). This research project aims to improve the evaluation of the seismic fragility of existing bridges of Québec road network and optimize the seismic design for future structures according to the performance based seismic approach. In particular, the project seeks to address the significant uncertainties which remain on the quantitative description of the limit states of the reinforced concrete bridge columns, particularly at the associated deformations level.
173

在不同工作特性下,酬勞誘因對組織績效之影響:實地實證研究

李伶珠, Lee, Ling Chu Unknown Date (has links)
傳統代理理論主張,企業可利用績效酬勞激勵員工努力工作,提昇組織績效;而競賽理論則強調,利用同儕競賽,並擴大勝負間的酬勞差距,以達企業利潤極大化目標。績效酬勞與競賽誘因對員工投入的努力皆具正面激勵效果,然而,在不同工作特性下,酬勞誘因隨著員工工作所需的合作程度不同,對組織績效的影響卻有所差異。 本文首先依據代理理論與競賽理論模型,將績效酬勞與競賽誘因同時納入酬勞誘因制度中,以利分析在不同工作特性的情況下,酬勞誘因對於營業單位經營績效之影響。在績效酬勞對經營績效之影響上,理論分析結果發現:不論對員工工作彼此獨立或對工作需合作的營業單位而言,績效酬勞的增加,都可提高經營績效;當隨機干擾因素增加,因員工獲得酬勞的不確定性增加,進而削弱員工努力的意願,降低營業單位之經營績效。在競賽誘因對組織績效的影響方面,靜態分析結果指出:在不同工作特性的情況下,競賽誘因會出現不同的效果。當員工工作彼此獨立時,擴大競賽後贏家與輸家間的酬勞差距,有利於組織績效之提高。相對的,在員工工作彼此合作的情況下,酬勞差距擴大後,一方面使員工最適個人努力提高,有益於組織經營績效;另一方面卻削弱員工彼此合作的意願,降低協助同儕的努力,兩種效果抵銷之後,使得酬勞誘因對組織經營績效之提昇受到限制。 本文以一家大型連鎖汽車公司為個案公司,研究期間為2001年至2004年,包括86個營業所及90家汽車修護廠的營業績效資料及中低階層員工之酬勞資料,以實地實證研究法進行實證研究。研究結果發現,當員工工作彼此獨立時,營業單位之個人績效酬勞愈大或收入變異程度愈小者,績效愈好;當員工工作彼此需要合作時,營業單位之團體績效酬勞愈大或收入變異程度愈小者,績效愈好。在競賽誘因方面,當員工工作彼此獨立時,不論是職務間或職務內的酬勞差距的擴大,皆對營業單位之經營績效具有正面提昇效果;相較於工作彼此獨立,當員工工作彼此需要合作時,職務間或職務內酬勞差距的擴大對營業單位績效提昇幅度顯著較小。由此可知,企業在進行酬勞誘因設計時,應同步考量工作特性與酬勞誘因機制間的配適性,俾利於組織績效的提昇。 / Agency theory suggests that organizations can motivate employees to exert their efforts by providing individual-based compensation. Tournament theory argues that, by encouraging competition among employees and increasing the compensation gaps between winners and losers, firms can direct employees’ actions in alignment with the firm’s interests. Both compensation schemes can induce employees’ efforts and increase corporate performance. However, the positive effects on corporate performance vary in the need of cooperation among employees, ranging from independent to interdependent tasks. This paper uses a theoretical and empirical analysis of performance-based and tournament-based incentives to examine the impacts of compensation incentives on branch performance. For the impacts of performance-based incentives on branch performance, the performance will increase in the individual performance-based incentives. When employees work independently, the greater the compensation gaps lead to more efforts and higher performance. When employees work interdependently, two contradictory effects of greater the compensation gaps make the performance change unclear. On the one hand, greater compensation gaps will increase employees’ efforts for being winner in the tournament. On the other hand, greater compensation gaps will induce employees not to help their competitors and hurt the performance, although help efforts can contribute firms profits. Using four years of data from a large car company with 86 car dealer branches and 90 car repair service branches, we find that for the independent tasks, the branch performance increase as individual performance-based compensation increases or revenue variance decreases. For the tasks needed cooperation among employees, the branch performance is increasing in group-based compensation or decreasing in revenue variance. Besides, we find that the larger the compensation gaps between inter- or intra-jobs, the branch performance for the independent tasks are better. The impacts of the compensation gaps on the interdependent tasks are smaller than on the independent tasks. Therefore, incentive policy rewards the best performances with the complementary fit between tasks design and compensation schemes
174

Usage de la tablette tactile par les personnes âgées : une approche écologique de l'évaluation et de l'aide à l'apprentissage / Cognitive impairment, learning process and tablet computers : contributing to the empowerment of aging people

Dupré, Lisa 12 April 2018 (has links)
Les nouvelles technologies de l’information et de la communication (TIC) pourraient contribuer à la prévention de l’isolement et au développement du sentiment de bien-être des adultes âgés, ainsi qu’à l’amélioration de la qualité de vie et de prise en charge des patients souffrant de maladie de type Alzheimer. La technologie tactile possiblement plus simple d’utilisation que l’ordinateur, y compris pour des personnes présentant des troubles neurocognitifs, constituerait une solution facilitatrice d’accès aux TIC. La formation reste toutefois l’un des déterminants majeurs de l’utilisation des technologies par des adultes âgés. Un accompagnement efficace nécessite la prise en compte des besoins des aînés et donc une évaluation fine de la nature des difficultés rencontrées et des aides à fournir. En conséquence, nous avons souhaité étudier les difficultés particulières des personnes âgées à utiliser ces technologies, mais aussi les conditions de l’aide dont ils peuvent bénéficier. Notre recherche s’est en particulier intéressée au téléphone (fixe et mobile) et à la tablette tactile, qui paraissent offrir l’avantage d’une plus grande simplicité d’utilisation que les ordinateurs et ainsi présenter un intérêt particulier pour les personnes âgées, y compris pour des personnes présentant des troubles neurocognitifs. L’objectif de ce travail était de déterminer s’il était possible d’expliquer des difficultés à utiliser les nouvelles TIC, propres aux personnes âgées, dans le but de leur proposer un accompagnement adapté. Une évaluation en situation et la comparaison des capacités d’utilisation des TIC d’adultes jeunes et âgés a montré que les adultes âgés se caractérisent par un plus grand nombre d’erreurs d’exécution et un besoin en aides plus précises et explicites, notamment pour l’utilisation des technologies mobiles. L’exploration du lien entre la nature des erreurs produites lors de l’utilisation des TIC et les compétences cognitives indiquait le caractère déterminent de la préservation des capacités d’inhibition ainsi que de la mémoire épisodique, en particulier du processus de récupération spontanée. Ces capacités étaient liées aux erreurs d’exécution et non aux omissions. La recherche d’une structuration de l’environnement informatif et d’une automatisation de certaines procédures de base indispensables à l’utilisation des TIC apparait donc comme une très probable orientation permettant de pallier les difficultés des personnes âgées. Enfin, la participation à un programme d’initiation à l’utilisation des tablettes tactiles, intégrant les principes de l’apprentissage sans erreur et de la récupération espacée, permettait d’améliorer les attitudes à l’égard des technologies ainsi que les performances lors de leur utilisation. / In modern society, use of information and communication technologies (ICTs) is critical in order to avoid exclusion from many common modern day activities. Furthermore, longer life expectancy presents a major challenge to support dependent seniors, or those at risk of losing their independence but wish to continue living in their own home. ICTs seem particularly relevant in this context. Indeed, they promote social engagement, facilitate access to social networks, and provide a gateway to a wide range of information. Of particular interest in the present study are landline or mobile phones, and tablet computers, which are more readily portable, offer simpler functionality than most computers, and therefore are potentially very useful for aging people, included people with neurocognitive disorders. Broadly, such ICTs help to maintain and improve autonomy. Despite these potential benefits, seniors do not commonly use ICTs. Age-related physical and cognitive decline may affect the ability of older people to use ICTs. Therefore, it is essential to promote education and learning. However, an adapted and effective support could not exist without a fine evaluation of the nature of the difficulties and of the efficient cues. Consequently, we wanted to study the particular difficulties of older people in using these technologies, but also the conditions of the assistance they can benefit from. The objectif of this thesis project was to determine whether elderly encountered specific difficulties in using new ICT, in order to offert them an adapted support. A performance-based assessment and a comparison of the capacity of ICT ise of young and old adults has shown that older adults are characterized by a greater number of commission errors and a need for more precise and explicit cues, especially for the use of mobile technologies. Exploring the link between the nature of errors produced in the use of ICTs and cognitive skills indicated the determinent factor of inhibition abilities as well as episodic memory, in particular the spontaneous recovery process. These abilities were related to commission errors and not to omissions. Structuring the informative environment and automation of some basic procedures essential to the use of ICTs therefore appear as a very probable orientation to alleviate the difficulties of the elderly. Finally, participation in a tablet computer training program using the errorless learning and spaced-retrieval techniques, allowed to improve attitudes towards technologies as well as the performance when they are used.
175

Monetära belöningssystem och dess effekter / Monetary reward system and its effects

Gustafsson, Anton, Nguyen, Ann-Sofie January 2019 (has links)
Monetära belöningssystem är vanligt förekommande inom organisationer och implementeras vanligtvis för att öka motivationen hos medarbetare för att kunna påverka deras prestation, dock kan det finnas andra effekter som det inte tas någon hänsyn till. Syftet med studien är att skapa kunskap och en djupare förståelse om effekter av monetära belöningssystem i arbetslivet och hur monetära belöningssystem påverkar prestationen. Den teoretiska referensramen komponerades av tidigare studier på monetära belöningssystem och olika motivationsteorier, såsom Maslows behovshierarki och Vrooms förväntansteori. För att samla in data har semistrukturerade intervjuer utförts med åtta informanter. Valet av informanter gjordes med vissa kriterier där kriterierna var att informanten skulle arbeta vid en arbetsplats där de hade ett monetärt belöningssystem som antingen baserades på individen eller gruppen prestation eller både individen och gruppen prestation. Studiens resultat visar att uppfattningen av det monetära belöningssystemet påverkas främst av hur trygg personen känner sig ekonomiskt. Det visar att det finns positiva effekter i form av ökad motivation, men att det även finns negativa effekter i form av minskad motivation i vissa fall. Studien visar även att det monetära belöningssystemet i vissa fall även kan bidra till stress, oro, rädsla för att misslyckas och försämrad kvalité i arbetsuppgifter som inte innefattas av det monetära belöningssystemet. I vissa fall visar resultatet även att samarbetet och kommunikationen blir lidande vid användning av ett belöningssystem som är baserat på individens prestation, medan i andra fall så påverkas inte samarbetet och kommunikationen av belöningssystemet som är baserat på individens prestation. Vi har kommit fram till att monetära belöningssystem har både positiva och negativa effekter och påverkar prestationen båda positivt och negativt och att det främst beror på hur ekonomiskt trygg personen känner sig. Organisationer behöver ta hänsyn till detta vid implementeringen av ett monetärt belöningssystem så att belöningssystemet kongruerar med organisationens intresse. / Monetary reward systems are common in organisations and are usually implemented to increase motivation amongst the employed. The goal is to have an impact on the performance, but there may be other effects that are not considered. The purpose of the study is to create knowledge and a deeper understanding of the effects of monetary reward systems in the working life and how monetary reward systems affect the performance. The theoretical frame of reference was composed of previous studies on monetary reward systems and various motivational theories, such as Maslow's hierarchy of needs and Vroom's expectancy theory. In order to collect data, semi-structured interviews have been conducted with eight informants. The selection was based on a few criteria where the criteria were that the informant would work at a workplace where they had a monetary reward system that either was based on the individual or group performances or both the individual and the group performances. The study's results show that the perception of the monetary reward system is affected primarily by how financially secure the person feels. It shows that there are positive effects like increased motivation, but that there are also negative effects in terms of reduced motivation in some cases. The study also shows that in some cases the monetary reward system also contributes to stress, concern, fear of failure and a deterioration in the quality of tasks that are not included in the monetary reward system. In some cases, the result also shows that the cooperation and communication suffer when using a reward system that targets the individual's performance, while in other cases the cooperation and communication of the reward system that is based on the individual's performance is not affected. We have concluded that monetary reward systems have both positive and negative effects and affect both performances positively and negatively and that it depends primarily on how financially secure the person feels. Organizations need to take this into account when implementing a monetary reward system, so that the reward system correspond with the organisation's interest
176

Elitidrott och självkänsla : Lagidrottares upplevelser av sin självkänsla kopplat till elitidrott / Elite sports and self-esteem : Team athletes´experiences of self-esteem in elite sports

Karlsson, Lisa January 2019 (has links)
Undersökningen har studerat hur sex elitidrottande kvinnor upplever sin självkänsla kopplat till bas-självkänsla och prestationsbaserad självkänsla. Det tar utgångspunkt i att elitidrott är en prestationsinriktad miljö som med omgivningens krav ställer press på idrottarna. Undersökningen utgick från två olika perspektiv, de som är aktiva och de som inte är aktiva, där antalet var jämnt fördelat. Respondenterna delades sedan in i en av fyra grupper som mäter hur hög eller låg bas-självkänslan och den prestationsbaserade självkänslan är. Grupp 1 beskrivs som hög bas-självkänsla och hög prestationsbaserad självkänsla, grupp 2 beskrivs som låg bas- självkänsla och hög prestationsbaserad självkänsla. Resterande grupper 3 och 4 beskrivs antingen ha hög eller låg bas-självkänsla och låg prestationsbaserad självkänsla. Undersökningens resultat visade på att tre av respondenterna blev placerade i grupp 1 och tre respondenter i grupp 2. Resultatet av undersökningen menar på att samtliga respondenter upplever en hög prestationsbaserad självkänsla, som kännetecknas genom att de har en stark tillhörighet till sin idrott och upplever starka känslor för att prestera. Varje respondent påverkas olika men utgår efter liknande känslor och tankar vilket skapar en tydlig bild över att fenomenet kan skapa motivation till att prestera men också vara en faktor till att psykisk ohälsa existerar inom idrotten. / The study has shown how six women in elite sports experience their self-esteem based on basic self-esteem and performance-based self-esteem. This is developed on the premise that elite sports are a performance-oriented environment which, with the demands of the environment, puts pressure on the athletes. The study takes on two different perspectives, those that are active and those who are not active anymore, where the number is evenly distributed. The respondents were then divided into one of four groups, that measure how high or low the base self-esteem and the performance-based self-esteem are. Group 1 is described as high-base self-esteem and high-performance-based self-esteem, group 2 is described as low-base self-esteem and high performance-based self- esteem. Remaining groups 3 and 4 are described as having either high or low base self-esteem and low performance-based self-esteem. The results of the survey showed that three of the respondents were placed in group 1 and three of the respondents in group 2. The survey states that all respondents experience a high performance-based self-esteem, which is characterized by having a strong belonging for their sport and experiencing strong feelings for performing. Each respondent is affected differently but is based on similar feelings and thoughts. It creates a clear picture that the phenomena can be able to bring motivation to performance but also develop the mental illness that exists in sport.
177

Les fonctions exécutives chez les enfants et adolescents soignés pour une tumeur cérébrale : approche clinique des perturbations en situation d’examen et de vie quotidienne / Executive functions in children and adolescents treated for a brain tumor : Clinical approach of impairments in conventional examination and in daily life

Georges Roche, Jeanne 21 December 2017 (has links)
Les séquelles neuropsychologiques associées aux tumeurs cérébrales pédiatriques représentent un enjeu de santé publique. Les troubles des fonctions exécutives sont désormais avérés chez ces enfants mais la nature des processus perturbés, les modalités d'évaluation à préconiser et l'impact des variables démographiques/médicales liées à la maladie restent méconnus. L'objectif de cette thèse était de mieux comprendre le profil de perturbation des différents processus exécutifs dans ce contexte clinique, en confrontant des mesures basées sur la performance et des indicateurs de vie quotidienne (dans le contexte familial et scolaire). Dans cette perspective, nous avons 1) analysé le profil exécutif de 171 enfants d’âge scolaire atteints d'une tumeur cérébrale à la BRIEF (Inventaire d'évaluation comportementale des fonctions exécutives) et 2) étudié la convergence de ces indicateurs avec des mesures basées sur la performance adaptées en français auprès de 27 patients appariés à des enfants sains. L’influence des variables cliniques sur les profils exécutifs a été examinée. Des difficultés exécutives étendues mais variables ont été identifiées dans le quotidien des patients (tous types histologiques et localisations) au domicile et à l’école, avec par ailleurs des difficultés accrues rapportées par les parents en cas d’irradiation à un âge précoce. Des perturbations du contrôle exécutifs ont confirmées dans les mesures directes, dont la convergence avec les questionnaires apparait cependant limitée. Sur la base de ces résultats, sont discutés les apports respectifs de ces deux types d’outils pour appréhender la problématique exécutive dans le cadre des tumeurs pédiatriques. / Neuropsychological sequelae associated with pediatric brain tumors represent a major public health issue.Disorders of executive functions have been identified among these children, but the nature of the impaired processes, recommended evaluation modalities and the impact of demographic and medical variables related to the disease remain unclear. The aim of this thesis was to get a broader understanding of the disturbance profile of the different executive processes in this disease context, comparing performance-based measures and daily life indicators (in both the school and home environment). From this perspective, we have 1) analyzed the executive profile of 171 school age children with a brain tumor in the BRIEF (Behavior Rating Inventory of Executive Function) and 2) examined the association of these indicators with performance-based measures adapted in French in 27 patients matched to healthy children. The influence of clinical variables on the executive profiles was discussed. Broad and variable executive difficulties have been identified in patients’ everyday life (all tumor types and locations) at home as well as school, with also increased difficulties reported by parents in the case of radiation therapy at an early age. Disturbances of executive control are confirmed in direct measures, whose convergence with the questionnaires appears however limited. Based on these results, respective contributions of these two types of tools are discussed in order to understand the executive issue in pediatric brain tumor survivors.
178

Approche performantielle et microstructurale de la durabilité de bétons à base de ciments sulfoalumineux-bélitiques ferriques / Microstructural and performance-based approach of the durability of belite-ye’elimite-ferrite cements based concretes

Schmitt, Emmanuel 20 October 2014 (has links)
Les ciments sulfoalumineux (CSA) peuvent être une solution à l’amélioration de l’impact environnemental des bétons, grâce aux faibles consommations énergétiques et émissions de CO2 lors de leur fabrication. Leurs propriétés expansives, de rapidité de prise et de montée en résistance participent également à l’intérêt grandissant dans les domaines de la construction et de la préfabrication en béton pour ce type de liant. Toutefois, la durabilité des bétons sulfoalumineux reste encore méconnue ou discutée, notamment en milieux acides et face à la corrosion des armatures, en ambiance marine et par carbonatation. Les travaux présentés dans cette thèse se proposent ainsi d’étudier et de comparer la durabilité face à ces attaques, de bétons sulfoalumineux à celle de bétons de référence à base de CEM I et de CEM III/B. Ils s’appuient sur des caractérisations performantielles (indicateurs de durabilité, essais performantiels en conditions accélérées ou naturelles) et microstructurales (phases solides, porosité). Au préalable, l’application des caractérisations sus-citées aux bétons sulfoalumineux est vérifiée et discutée. La bonne résistance des bétons sulfoalumineux aux milieux acides est observée lors d’essais de lixiviation dynamique, à température et pH régulés. L’étude de la pénétration des chlorures (migration en régime permanent et transitoire, isothermes de fixation, exposition en zone de marnage) et de la carbonatation (naturelle et accélérée) de bétons à base de 8 ciments sulfoalumineux de laboratoire différents a permis d’établir des moyens d’améliorer leur durabilité potentielle. Ces moyens ont été appliqués à la fabrication d’un ciment industriel performant, dont la bonne durabilité reste toutefois à confirmer définitivement en conditions réelles. / Calcium sulfoaluminate (CSA) cements can be a solution to improve the environmental impact of concrete, thanks to the lower energy consumption and CO2 emission during their production. Their expansive, fast setting and rapid hardening properties contribute to the growing interest of engineers for concrete construction and prefabrication. However, the durability of sulfoaluminate concretes is not clearly assessed yet, especially in acidic and marine environments, as well as carbonation and chloride induced rebars corrosion. Thus, the aim of this thesis is to study and compare the durability, related to these attacks, of concretes made with CSA cements to ordinary Portland and GGBS cements based reference concretes. This study is founded on microstructural (solid phases, porosity) and performancial (durability indicators, natural and accelerated tests) characterization. Beforehand, the application of these characterizations to CSA concretes is verified and discussed. These show a good resistance to acidic environments when submitted to dynamic leaching tests at pH 3 and 5. The study of chloride ingress (steady and non-steady state migration, binding isotherms and tidal zone exposition) and carbonation (natural and accelerated) in concretes of 8 different laboratory CSA cements enabled us to find achievable means to improve their potential durability. These means were applied to the production of a performant industrial CSA cement, whose good durability has still to be assessed on field conditions.
179

Sustentabilidade e inovação no setor brasileiro da contrução civil: um estudo exploratório sobre a implantação da política pública baseada em desempenho / Sustainability and Innovation on the Brazilian Building Sector: An exploratory study about the performance-based implementation of the public housing policy

Bismarchi, Luis Felipe 09 June 2011 (has links)
O objetivo principal deste trabalho é identificar quais são os possíveis impactos que a adoção de um novo modelo de contratação de empreendimentos populares pela Caixa Econômica Federal (CAIXA) tem sobre a promoção da inovação e da sustentabilidade na cadeia brasileira da construção civil. Apesar de possuir diversas definições, o conceito mais aceito de sustentabilidade é a capacidade de atender as necessidades do presente sem impedir que as futuras gerações satisfaçam suas necessidades. O movimento em prol da sustentabilidade vem se fortalecendo rapidamente no mundo no início deste século XXI, instigando a sociedade civil a repensar seu comportamento de consumo, impactando diretamente sobre o comportamento de produção das empresas. Neste processo de mudança, a capacidade de inovar, isto é, de produzir novos conhecimentos ou aplicar de maneira diferentes conhecimentos existentes, é estratégica para que as empresas possam se adaptar a este novo contexto em que a sustentabilidade é requisito de participação no mercado. Um modelo de compra estratégica de empreendimentos populares baseado em desempenho, ao modificar a metodologia de seleção, contratação e acompanhamento das construtoras se apresenta como uma maneira do Estado influenciar o setor brasileiro da construção civil em direção à sustentabilidade. Através de uma pesquisa exploratória teórica, apresentamos uma forma de aplicação do modelo de compra estratégica baseada em desempenho desenvolvida nos Estados Unidos no início dos anos 1990 e identificamos seu potencial em estimular a sustentabilidade, devido principalmente à maneira como são descritas as características dos empreendimentos a serem construídos, e a inovação, devido à maneira como se dá a relação entre proponentes e a CAIXA durante o processo de seleção dos empreendimentos. A principal conclusão desta pesquisa é que o modelo apresentado tem um potencial muito maior que o atual em promover a inovação e a sustentabilidade no setor brasileiro da construção civil, uma vez que apresenta novos papéis e uma nova dinâmica de relacionamento entre todos os agentes envolvidos na implantação da política pública de habitação. / The main purpose of this research is to identify the possible impacts the adoption of a new purchasing model of popular buildings by Caixa Econômica Federal (CAIXA) has on the promotion of innovation and sustainability in the Brazilian building chain. Despite several definitions, the most accepted concept of sustainable development is the development which meets the needs of the present without compromising the ability of future generations to meet their own needs. The sustainability movement is quickly getting stronger in the beginning of the 21st century, urging civil society to rethink its consumption pattern. This has a direct impact over companies production pattern. On this change process, the ability to innovate, that is, to develop new knowledge or apply in different matters the existing knowledge, is strategic to companies adapt to this new context where sustainability is a condition to keep in market. A performance-based procurement model of popular housing, once it modifies the methodology of selection, award and monitoring building companies, becomes a way to the State promote the Brazilian building sector towards sustainability. Through a theoretical exploratory research, we present a model of performance-based procurement developed in the USA in the 1990´s and we identify its potential to promote sustainability and innovation, mainly due to the way the request for proposal is done. The main finding of this research is that the presented model has a greater potential than the actual one to foster innovation and sustainability in the Brazilian building sector, once it presents new roles and a new relationship dynamics among all agents involved in the implementation of the public housing policy.
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Performance-Based Analysis of a Reinforced Concrete Shear Wall Building

Hagen, Garrett Richard 01 June 2012 (has links)
PERFORMANCE-BASED ANALYSIS OF A REINFORCED CONCRETE SHEAR WALL BUILDING Garrett Richard Hagen In this thesis, a special reinforced concrete shear wall building was designed per ASCE 7-05, and then the performance was investigated using the four analysis procedures outlined in ASCE 41-06. The proposed building was planned as a 6-story office building in San Francisco, CA. The structural system consisted of a two-way flat plate and reinforced concrete columns for gravity loads and slender structural walls for seismic loads. The mathematical building models utilized recommendations from ASCE 41-06 and first-principle mechanics. Moment-curvature analysis and fiber cross-section elements were used in developing the computer models for the nonlinear procedures. The results for the analysis procedures showed that the building met the Basic Safety Objective as defined in ASCE 41-06. The performance levels for the nonlinear procedures showed better building performance than for the linear procedures. This paper addresses previously found data for similar studies which used steel special moment frames, special concentric braced frames, and buckling restrained braced frames for their primary lateral systems. The results showcase expected seismic performance levels for a commercial office building designed in a high seismicity region with varying structural systems and when using different analysis procedures. Keywords: reinforced concrete structural walls, shear walls, performance-based analysis, ETABS, Perform-3D, flat plate, two-way slab.

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