Roofs are the single enclosure element common to artificial shelters constructed by all cultures in all climate regions. The hygrothermal performance of insulated, sloped, wood-framed roof assemblies has long been of interest to building scientists and building codes alike. Requirements for the ventilation of roof assemblies have been included in building codes for more than 50 years, however moisture problems still occur. Unvented roof assemblies have been suggested as an alternate and potentially superior solution. While unvented roofs have become relatively common in the warmer southern climates of North America, some technical issues remain unclear and the need exists for further study and demonstration of the hygrothermal performance of both ventilated and unvented roof assemblies in cold northern climates. This thesis seeks to address these issues through a review of existing literature, experience and industry practice, field investigation and measurement, analytical calculation and computer simulations.

In passive RFID systems, how to reduce the collision among tags is an important issue at the medium access control layer. The Framed Slotted ALOHA and its variations are well-known anti-collision algorithms for RFID systems. However, when the Framed Slotted ALOHA is used, the system efficiency and the average time delay deteriorate rapidly when the total number of tags increases. On the other hand, the total number of slots in a frame can¡¦t be infinity. In this thesis, we first compare existing anti-collision protocols and then propose a novel algorithm based on the Enhanced Dynamic Framed Slotted ALOHA (EDFSA) and the Progressing Scanning (PS) algorithm. The proposed algorithm is called Dynamic Grouping (DG). The DG algorithm partitions the RFID tags according to the distances from tags to the reader in order to avoid using too many slots in a frame. Inparticular, the DG algorithm estimates the spatial distribution of tags based on previous scanning results and then adjusts the partition accordingly. Unlike PS algorithm, the DG algorithm is applicable when the RFID tags are uniformly distributed or normally distributed.

Building Information Modeling (BIM) is the comprehensive process of developing a computer model of a building project in the phases of designing, analyzing, building, managing, refurbishing and even demolishing the building. Applying BIM to public construction has become an obligation in South Korea. According to the Public Procurement Service in South Korea, the use of BIM has been compulsory on all government projects over $44M since 2012. Moreover, from 2013, the application of BIM will be expanded to all public construction projects over $27.6M. Finally, beginning in 2016, all public construction projects will be required to use BIM. Most research on BIM in South Korea has been focused on developing regulations and policies, application of BIM, solving technical problems, and searching for the value of BIM. However, the use of BIM in Korea during construction for decision-making has not been thoroughly reported in Korea yet. One may be wondering then if BIM is indeed well utilized in Korea during construction for practical decision-making. The objective of this research centers on investigating how a construction company in South Korea is using BIM for its decision making process during ongoing construction phases. For this investigation, a case study method was used. The construction operations on a jobsite in South Korea were monitored June to August in 2012. Field notes were taken to document the decision-making process and information used during field coordination meetings. A total of 36 cases were monitored and recorded. The use of BIM on field was then compared to the industry expectations indicated in the literature. Specifically, the use of BIM for scheduling, estimating, coordination, review of drawings, and tracking for change orders were carefully monitored and compared with the industry expectations as they were addressed in the literature. The results of this research study were mixed. That is, there are not only similarities, but also differences between BIM’s role used for decision making at the construction site, and its expected role described in previous research. The similarities were regarded as minimizing reworking. This factor came to fruition at a construction site by minimizing error, omission in design phases, or congruence in design and construction tasks. These factors could have a positive effect on estimating and scheduling at a construction site. However, use of BIM at a construction site was still limited in reducing repetitive work when 2D drawings were not able to provide enough information to conduct construction. Additionally, even though this study was successful in revealing the connection between the decision making process and the application of BIM at a construction site, the results of the study may not be generalizable to the construction industry as a whole in South Korea. Therefore, further research is needed to ensure its applicability to other construction projects.

Made available in DSpace on 2014-06-11T19:25:21Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-05-25Bitstream added on 2014-06-13T20:13:40Z : No. of bitstreams: 1 manera_rs_me_ilha.pdf: 1781622 bytes, checksum: df51260a9abc905f915b3ff67132b0bb (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Atualmente no Brasil, há a necessidade de se construir novas pontes, além da grande demanda por pontes de pequenos e médios vãos em novas regiões agrícolas. Com este propósito, a empresa Galvani propôs um sistema estrutural que será utilizado como estrutura principal de uma ponte de madeira, sendo utilizada madeira de reflorestamento da espécie Eucalipto Citriodora. O sistema estrutural estudado consiste em um pórtico pré-tensionado, com duas peças de madeira roliça com 15 metros de altura interligadas por um nó metálico em seu topo, essas peças terão um travamento horizontal efetuado por uma peça de madeira roliça a três quartos da altura da base do pórtico. Este pórtico será a sustentação principal, por tirantes, de um tabuleiro de uma ponte de 5 metros de largura por 30 metros de comprimento. O estudo necessário foi realizado para que este sistema estrutural atenda a todos os requisitos das normas técnicas da ABNT vigentes no país e que satisfaça a expectativa do seu principal idealizador, o engenheiro civil Rodolfo Galvani Júnior / Currently in Brazil it's necessary to build new bridges, because there are a large demand for small and medium bridges in new agricultural areas. For this purpose, the company Galvani proposed a new structural system to be used as the principal structure of a wooden bridge, and is used the reforestation wood of species Eucalyptus citriodora. The structural system consists to apply a displacement at the base of the principal structure and will be analyzed its influence in improving the structural behavior when it is loaded. The principal structure have two pieces of roundwood with 15 meters of height and both are connected with the use of metal profiles, these parts will have a lock on a horizontal piece of roundwood to three quarters of the height of base of the structure. This principal structure is used like a support of a main board of a bridge of 5 meters width by 30 meters in length. The objective of this research is study this new structural scheme complies with the requirements of technical standards ABNT and meets the expectation of engineer civil Rodolfo Galvani Junior

Este trabalho apresenta conceitos e procedimentos que devem ser considerados na análise dinâmica de fundações de máquinas. São discutidas as abordagens e os métodos de cálculo à disposição dos engenheiros, assim como os fatores que influenciam a escolha e o desenvolvimento de modelos matemáticos adequados. Três tipos diferentes de fundação (fundações em bloco rígido, fundações de martelos e fundações aporticadas) são examinados, e são utilizados exemplos para demonstrar a eficácia de técnicas simples de modelagem. / This paper presents concepts and procedures necessary to the dynamic analysis of machine foundations. Analytical approaches available to the designer, and factors which influence the choice and development of a suitable analytical model are discussed. Three different foundations (block foundations, hammer foundations and framed foundations) are examined and examples are given to demonstrate the effectiveness of simple modeling techniques.

To understand how to better stimulate adult sport engagement, this study investigated effects of gain-framed messages (GFM; Rothman & Updegraff, 2010) on psychological/behavioural outcomes, with or without efficacy-enhancing messages (Latimer et al., 2010). Eligible adults (30-69 years-old) were randomly assigned to one of two experimental conditions (‘GFM alone’ or ‘GFM plus efficacy-enhancing messages’), or a control condition. Participants (N = 232; 62.5% female) completed baseline/screening measures, watched their messaging intervention and reported outcomes one-week later (Time 2), and responded one-month later (Time 3). Comparing the experimental conditions showed non-significant differences for all outcomes, indicating no added benefit of efficacy-enhancing messages. Collapsing the experimental groups and comparing against the control showed significant group-by-time interactions for three ‘outcome expectancies’ (travel, social affiliation, stress relief), with reports higher among experimental participants. Results also indicated that moderate-to-vigorous physical activity significantly decreased at Time 3 within the control, but remained constant among experimental participants.

京都大学 / 0048 / 新制・論文博士 / 博士(理学) / 乙第12910号 / 論理博第1546号 / 新制||理||1590(附属図書館) / 32120 / ソウル大学大学院数学科 / (主査)教授 中島 啓, 教授 小野 薫, 教授 向井 茂 / 学位規則第4条第2項該当 / Doctor of Science / Kyoto University / DFAM

No description available.

In this study, methods for the geometric nonlinear analysis and the material nonlinear analysis of plane frames subjected to elevated temperatures are presented. The method of analysis is based on a Eulerian (co-rotational) formulation, which was developed initially for static loads, and is extended herein to include geometric and material nonlinearities. Local element force-deformation relationships are derived using the beam-column theory, taking into consideration the effect of curvature due to temperature gradient across the element cross-section. The changes in element chord lengths due to thermal axial strain and bowing due to the temperature gradient are also taken into account. This "beam-column" approach, using stability and bowing functions, requires significantly fewer elements per member (i.e. beam/column) for the analysis of a framed structure than the "finite-element" approach. A computational technique, utilizing Newton-Raphson iterations, is developed to determine the nonlinear response of structures. The inclusion of the reduction factors for the coefficient of thermal expansion, modulus of elasticity and yield strength is introduced and implemented with the use of temperature-dependent formulas. A comparison of the AISC reduction factor equations to the Eurocode reduction factor equations were found to be in close agreement. Numerical solutions derived from geometric and material analyses are presented for a number of benchmark structures to demonstrate the feasibility of the proposed method of analysis. The solutions generated for the geometrical analysis of a cantilever beam and an axially restrained column yield results that were close in proximity to the exact, theoretical solution. The geometric nonlinear analysis of the one-story frame exhibited typical behavior that was relatively close to the experimental results, thereby indicating that the proposed method is accurate. The feasibility of extending the method of analysis to include the effects of material nonlinearity is also explored, and some preliminary results are presented for an experimentally tested simply supported beam and the aforementioned one-story frame. The solutions generated for these structures indicate that the present analysis accurately predicts the deflections at lower temperatures but overestimates the failure temperature and final deflection. This may be in part due to a post-buckling reaction after the first plastic hinge is formed. Additional research is, therefore, needed before this method can be used to analyze the materially nonlinear response of structures.

No description available.