The expansion of social housing in Brazil is solving the great demand among low-income populations, ltowever, these projects are not considering climatic factors and thermal comfort strategies. There is a standardizat...The expansion of social housing in Brazil is solving the great demand among low-income populations, ltowever, these projects are not considering climatic factors and thermal comfort strategies. There is a standardization of architectural projects, which leads to the user discomfort. Bioclimatic solutions that improve the thermal performance of buildings should be valued in the projects of buildings. This paper presents a comparative study noticing the thermal comfort provided by a earth tube ventilation system with a natural ventilation system based in the opening of the windows. In this study, three Brazilian bioclimatic zones defined by NBR （Brazilian Standard） 15220 （2005）, Zone 1 （Curitiba）, 2 （Camaqu~,） and 7 （Cuiabfi）, were considered. To make this comparison, computer simulation was used to observe the thermal confort conditions in RTQ-R （Quality Technical Standard for Energy Efficiency Level in Residential Buildings） （2010）, with the help of Energy Plus software and Schektch Up with the plug in Open Studio for modeling the residence. After the energy modeling, the results were analyzed with the Analisys Bio software in order to obtain the percentage of hours of comfort for the year （8,760 h）. The conclusion is drawn that the natural ventilation strategy with the opening and closing of the windows is more efficient in Bioclimatic Zone 1. For the Bioclimatic Zone 2, the earth tubes should be used only in the summer and, in Bioclimatic Zone 7, earth tubes are efficient throughout the year because of the high temperatures in the exterior environment.展开更多
In Ethiopian construction projects, schedule delay risk is a predominant issue because it is not properly addressed. Although several studies have been focused on the various effects of risk in construction projects, ...In Ethiopian construction projects, schedule delay risk is a predominant issue because it is not properly addressed. Although several studies have been focused on the various effects of risk in construction projects, limited efforts have been made to investigate the typical and the overall schedule delay risk. In this study, our aim is to detect the typical and overall schedule delay risk throughout the construction project lifecycle, which consists of the pre-construction, construction, and post-construction stages, and compare the stages with each other. Common criteria, sub-criteria, and attributes were developed for all alternatives for the purpose of making a risk decision. The methodology that was followed integrated the multiplecriteria decision-making(MCDM) model of fuzzy analytic hierarchy process comprehensive evaluation(FAHPCE)and the relative important index(RII). Data were collected from 77 participants, who were selected through purposive sampling from different contracting organizations in Ethiopian construction projects by means of questionnaires that were distributed to experienced experts. The findings showed that there is a typical delay risk either in the type or in the level of the different construction activities.Consequently, the most influenced alternative is the construction stage because of the high-risk responsibility,resource, and contract condition related criteria. The postconstruction stage was the second most influenced stage because of the high-risk responsibility-related criteria. The pre-constructed stage was the least influenced stage that consist high-risk criteria of responsibility, resource, and contract condition related. These differences provided noteworthy information about risk mitigation in construction projects by identifying the exact risk level on specific activity to make appropriate decision.展开更多
文摘The expansion of social housing in Brazil is solving the great demand among low-income populations, ltowever, these projects are not considering climatic factors and thermal comfort strategies. There is a standardization of architectural projects, which leads to the user discomfort. Bioclimatic solutions that improve the thermal performance of buildings should be valued in the projects of buildings. This paper presents a comparative study noticing the thermal comfort provided by a earth tube ventilation system with a natural ventilation system based in the opening of the windows. In this study, three Brazilian bioclimatic zones defined by NBR （Brazilian Standard） 15220 （2005）, Zone 1 （Curitiba）, 2 （Camaqu~,） and 7 （Cuiabfi）, were considered. To make this comparison, computer simulation was used to observe the thermal confort conditions in RTQ-R （Quality Technical Standard for Energy Efficiency Level in Residential Buildings） （2010）, with the help of Energy Plus software and Schektch Up with the plug in Open Studio for modeling the residence. After the energy modeling, the results were analyzed with the Analisys Bio software in order to obtain the percentage of hours of comfort for the year （8,760 h）. The conclusion is drawn that the natural ventilation strategy with the opening and closing of the windows is more efficient in Bioclimatic Zone 1. For the Bioclimatic Zone 2, the earth tubes should be used only in the summer and, in Bioclimatic Zone 7, earth tubes are efficient throughout the year because of the high temperatures in the exterior environment.
文摘In Ethiopian construction projects, schedule delay risk is a predominant issue because it is not properly addressed. Although several studies have been focused on the various effects of risk in construction projects, limited efforts have been made to investigate the typical and the overall schedule delay risk. In this study, our aim is to detect the typical and overall schedule delay risk throughout the construction project lifecycle, which consists of the pre-construction, construction, and post-construction stages, and compare the stages with each other. Common criteria, sub-criteria, and attributes were developed for all alternatives for the purpose of making a risk decision. The methodology that was followed integrated the multiplecriteria decision-making(MCDM) model of fuzzy analytic hierarchy process comprehensive evaluation(FAHPCE)and the relative important index(RII). Data were collected from 77 participants, who were selected through purposive sampling from different contracting organizations in Ethiopian construction projects by means of questionnaires that were distributed to experienced experts. The findings showed that there is a typical delay risk either in the type or in the level of the different construction activities.Consequently, the most influenced alternative is the construction stage because of the high-risk responsibility,resource, and contract condition related criteria. The postconstruction stage was the second most influenced stage because of the high-risk responsibility-related criteria. The pre-constructed stage was the least influenced stage that consist high-risk criteria of responsibility, resource, and contract condition related. These differences provided noteworthy information about risk mitigation in construction projects by identifying the exact risk level on specific activity to make appropriate decision.
