Some sufficient and necessary conditions that implication algebra on a partial ordered set is associated implication algebra are obtained, and the relation between lattice H implication algebra and associated implicat...Some sufficient and necessary conditions that implication algebra on a partial ordered set is associated implication algebra are obtained, and the relation between lattice H implication algebra and associated implication algebra is discussed. Also, the concept of filter is proposed with some basic properties being studied.展开更多
One primordial consideration in residential ventilation standards is the comfort of provided to people living in those habitations.This is highly dependent on the thermal and fluid flow conditions,the space geometry a...One primordial consideration in residential ventilation standards is the comfort of provided to people living in those habitations.This is highly dependent on the thermal and fluid flow conditions,the space geometry and so on.Efficient designs may reduce the energy usage,making the buildings more sustainable over a longer period of time.This study aims to investigate the impact of whole day thermal conditions on the fluid flow structure and heat transfer phenomena,mainly natural convection,inside a partitioned attic-shaped configuration.The Finite Volume Method is applied to solve the governing equations.Sinusoidal thermal boundary condition is applied on the sloping walls to illustrate the characteristics of primary flow through daily cycles.A highly thermal conductive partition was placed vertically at the middle of the cavity.Note that through the partition,only heat could freely transfer between two fluid zones.Results show that,during day time,a stratified fluid flow structure is obtained,which originates from the prevailing conduction heat transfer mechanism,while,for the night-time it changed into a strong convection mechanism which significantly affects the flow structure.These results are particularly important for understanding the fluid dynamics inside the attic shaped building and also designing new residential building.展开更多
A roof solar chimney (RSC) is inclined in the roof of a building wherein solar radiation is employed to heat the air the channel. The hot air flows up the channel which can be used to induce flow out of the building i...A roof solar chimney (RSC) is inclined in the roof of a building wherein solar radiation is employed to heat the air the channel. The hot air flows up the channel which can be used to induce flow out of the building in order to ventilate it. In this study, parameters that affect the performance of this natural ventilation system were investigated numerically, namely: inclination angles, channel gaps, solar intensities, vertical chimney attachment heights and channel expanding angles. The two last parameters were new concepts that seem to have never been studied before. All of the mentioned parameters were found to exhibit positive effects on the ventilation. Relative merits of these techniques were compared and discussed.展开更多
Materials with a low thermal emittance surface have been used for many years to create reflective insulations that reduce the rate of heat flow across building envelopes. Reflective insulation technology is now being ...Materials with a low thermal emittance surface have been used for many years to create reflective insulations that reduce the rate of heat flow across building envelopes. Reflective insulation technology is now being combined with other energy conserving technologies to optimize overall thermal performance. The basis for the performance of reflective insulations and radiant barriers will be discussed along with the combination of these materials with cellular plastic or mineral fiber insulations to form hybrid insulation assemblies. Calculations of thermal resistance for enclosed reflective air spaces and current field data from Southeast Asia will be presented. These data show that reductions in heat transfer across the building enclosure can be effectively reduced by the use of enclosed reflective air spaces and attic radiant barriers. Reflective technology increases the overall thermal resistance of the building enclosure when used to insulate poured concrete structures.展开更多
正正如不少人心中所怀的阁楼梦想,一间飘散着木质清香,能让你伴着鸟鸣醒来的山间小屋同样令人向往。在冬天,它意味着厚厚的羊绒毯,和炉火熊熊的壁炉;在夏天,它意味着冷冽的甘泉,和清新凉爽的空气。Dream about attic lays in many one’...正正如不少人心中所怀的阁楼梦想,一间飘散着木质清香,能让你伴着鸟鸣醒来的山间小屋同样令人向往。在冬天,它意味着厚厚的羊绒毯,和炉火熊熊的壁炉;在夏天,它意味着冷冽的甘泉,和清新凉爽的空气。Dream about attic lays in many one’sheart,chalet with the scent of wood andthe sound of birds also makes people展开更多
Attic cholesteatoma with antral extension in tight sclerotic mastoid cavities is a common presentation that creates difficult decision-making intraoperatively.Drilling through a sclerotic and small mastoid cavity,keep...Attic cholesteatoma with antral extension in tight sclerotic mastoid cavities is a common presentation that creates difficult decision-making intraoperatively.Drilling through a sclerotic and small mastoid cavity,keeping the canal wall intactis often difficult and increases the risk of serious injury.Consequently,a canal-wall-down mastoidectomy is often performed.The endoscopic transcanal modified canal-wall-down mastoidectomy approach al lows the benefits of an open cavity for cholesteatoma resection and the benefits of a closed cavity for better long-term care and a more normal ear canal and middle ear reconstruction.展开更多
阁楼里堆放着许多杂物,吉伯特在那里翻来翻 去,像是在寻找什么东西。 ——Gilbert:This year I am going to prepare a surprise for my birthday party．I began the preparations in the attic. 吉伯特:今年我将为我的生日派对准备 ...阁楼里堆放着许多杂物,吉伯特在那里翻来翻 去,像是在寻找什么东西。 ——Gilbert:This year I am going to prepare a surprise for my birthday party．I began the preparations in the attic. 吉伯特:今年我将为我的生日派对准备 一个惊喜。我开始在阁楼里做 准备工作。展开更多
基金Science & Technology Depart ment of Sichuan Province,China(No.03226125)the Education Foundation of Sichuan Province,China(No.2006A084)
文摘Some sufficient and necessary conditions that implication algebra on a partial ordered set is associated implication algebra are obtained, and the relation between lattice H implication algebra and associated implication algebra is discussed. Also, the concept of filter is proposed with some basic properties being studied.
文摘One primordial consideration in residential ventilation standards is the comfort of provided to people living in those habitations.This is highly dependent on the thermal and fluid flow conditions,the space geometry and so on.Efficient designs may reduce the energy usage,making the buildings more sustainable over a longer period of time.This study aims to investigate the impact of whole day thermal conditions on the fluid flow structure and heat transfer phenomena,mainly natural convection,inside a partitioned attic-shaped configuration.The Finite Volume Method is applied to solve the governing equations.Sinusoidal thermal boundary condition is applied on the sloping walls to illustrate the characteristics of primary flow through daily cycles.A highly thermal conductive partition was placed vertically at the middle of the cavity.Note that through the partition,only heat could freely transfer between two fluid zones.Results show that,during day time,a stratified fluid flow structure is obtained,which originates from the prevailing conduction heat transfer mechanism,while,for the night-time it changed into a strong convection mechanism which significantly affects the flow structure.These results are particularly important for understanding the fluid dynamics inside the attic shaped building and also designing new residential building.
文摘A roof solar chimney (RSC) is inclined in the roof of a building wherein solar radiation is employed to heat the air the channel. The hot air flows up the channel which can be used to induce flow out of the building in order to ventilate it. In this study, parameters that affect the performance of this natural ventilation system were investigated numerically, namely: inclination angles, channel gaps, solar intensities, vertical chimney attachment heights and channel expanding angles. The two last parameters were new concepts that seem to have never been studied before. All of the mentioned parameters were found to exhibit positive effects on the ventilation. Relative merits of these techniques were compared and discussed.
文摘Materials with a low thermal emittance surface have been used for many years to create reflective insulations that reduce the rate of heat flow across building envelopes. Reflective insulation technology is now being combined with other energy conserving technologies to optimize overall thermal performance. The basis for the performance of reflective insulations and radiant barriers will be discussed along with the combination of these materials with cellular plastic or mineral fiber insulations to form hybrid insulation assemblies. Calculations of thermal resistance for enclosed reflective air spaces and current field data from Southeast Asia will be presented. These data show that reductions in heat transfer across the building enclosure can be effectively reduced by the use of enclosed reflective air spaces and attic radiant barriers. Reflective technology increases the overall thermal resistance of the building enclosure when used to insulate poured concrete structures.
文摘正正如不少人心中所怀的阁楼梦想,一间飘散着木质清香,能让你伴着鸟鸣醒来的山间小屋同样令人向往。在冬天,它意味着厚厚的羊绒毯,和炉火熊熊的壁炉;在夏天,它意味着冷冽的甘泉,和清新凉爽的空气。Dream about attic lays in many one’sheart,chalet with the scent of wood andthe sound of birds also makes people
文摘Attic cholesteatoma with antral extension in tight sclerotic mastoid cavities is a common presentation that creates difficult decision-making intraoperatively.Drilling through a sclerotic and small mastoid cavity,keeping the canal wall intactis often difficult and increases the risk of serious injury.Consequently,a canal-wall-down mastoidectomy is often performed.The endoscopic transcanal modified canal-wall-down mastoidectomy approach al lows the benefits of an open cavity for cholesteatoma resection and the benefits of a closed cavity for better long-term care and a more normal ear canal and middle ear reconstruction.
文摘阁楼里堆放着许多杂物,吉伯特在那里翻来翻 去,像是在寻找什么东西。 ——Gilbert:This year I am going to prepare a surprise for my birthday party．I began the preparations in the attic. 吉伯特:今年我将为我的生日派对准备 一个惊喜。我开始在阁楼里做 准备工作。
