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1.
At Penn State, the credit for broadening the Civil Engineering Department’s longstanding academic focus on analysis and design to include the construction phase must go to Dr. Harmer A. Weeden and his longtime associate Dr. Thomas D. Larson. Jack H. Willenbrock joined the Department as an Instructor in June 1968 and grew the construction program so that today about a fourth to a third of the civil undergraduates obtain employment in the construction industry. The program has awarded about 250 postbaccalaureate degrees.  相似文献   
2.
This paper reports on the field study of a steel stringer-fiber reinforced polymer (FRP) deck composite bridge in Pennsylvania. The objective of the study is to assess the effective compression flange width in the FRP deck and floor systems when they act compositely with underlying steel girders at service conditions. The research results reported herein support the notion of employing a design approach, for both interior and exterior girders of a composite floor system, that is philosophically consistent with current practice related to steel girders acting compositely with concrete decking. It appears from the results presented herein that FRP decks and floors acting compositely with underlying steel girders exhibit an effective width that is close to the actual girder spacing for interior beams, and approximately one-half this value for exterior beams.  相似文献   
3.
童乔慧  郭婵娟 《华中建筑》2012,(11):156-159
宾夕法尼亚大学设计学院成立于19世纪末,许多著名的建筑师、理论家毕业于此,包括路易斯·康。20世纪初至少有15位中国留学生选择宾大建筑系进行深造,包括陈植、杨廷宝、梁思成、林徽因等。宾大教学过程中非常重视理论研究、实践探讨和艺术表达之间的关系。教师非常强调把这些多种学习结合在一起,注重对于问题的新思考模式研究。该文介绍了宾西法尼亚大学设计学院的历史沿革、教学情况、课程设置,探讨了设计学院的教学思想和课程设置特点,希望能为国内建筑教育提供一定的思考。  相似文献   
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Many states rely upon the Pennsylvania 1957 Gas Well Pillar Study to evaluate the coal barrier surrounding gas wells. The study included 77 gas well failure cases that occurred in the Pittsburgh and Freeport coal seams over a 25-year span. At the time, coal was mined using the room-and-pillar mining method with full or partial pillar recovery, and square or rectangle pillars surrounding the gas wells were left to protect the wells. The study provided guidelines for pillar sizes under different overburden depths up to213 m(700 ft). The 1957 study has also been used to determine gas well pillar sizes in longwall mines since longwall mining began in the 1970 s. The original study was developed for room-and-pillar mining and could be applied to gas wells in longwall chain pillars under shallow cover. However, under deep cover, severe deformations in gas wells have occurred in longwall chain pillars. Presently, with a better understanding of coal pillar mechanics, new insight into subsidence movements induced by retreat mining, and advances in numerical modeling, it has become both critically important and feasible to evaluate the adequacy of the 1957 study for longwall gas well pillars. In this paper, the data from the 1957 study is analyzed from a new perspective by considering various factors, including overburden depth, failure location, failure time, pillar safety factor(SF), and floor pressure. The pillar SF and floor pressure are calculated by considering abutment pressure induced by full pillar recovery. A statistical analysis is performed to find correlations between various factors and helps identify the most significant factors for the stability of gas wells influenced by retreat mining. Through analyzing the data from the 1957 study, the guidelines for gas well pillars in the 1957 study are evaluated for their adequacy for roomand-pillar mining and their applicability to longwall mining. Numerical modeling is used to model the stability of gas wells by quantifying the mining-induced stresses in gas well casings. Results of this study indicate that the guidelines in the 1957 study may be appropriate for pillars protecting conventional gas wells in both room-and-pillar mining and longwall mining under overburden depths up to 213 m(700 ft),but may not be sufficient for protective pillars under deep cover. The current evaluation of the 1957 study provides not only insights about potential gas well failures caused by retreat mining but also implications for what critical considerations should be taken into account to protect gas wells in longwall mining.  相似文献   
6.
丁力扬 《建筑师》2022,(6):113-118
本文回顾了2022 年1月底至6 月初在宾夕法尼亚大学费舍尔美术图书馆和建筑档案馆举办的“中国建造: 现代建筑百年对话”展览。旨在呈现展览的原貌,本文概述了展览的背景和缘起,介绍了展览的具体内容和策 展思路,并回顾了展览进行过程中和结束后来自各界的反响和评价。本文将“中国建造”展置于近二十年来一 系列有关宾夕法尼亚大学与中国现代建筑关系的学术活动的框架内,强调其目标是在立足于“第一代“中国建 筑师与宾夕法尼亚大学布扎体系首次交集的一个世纪之后,审视现代建筑发展进程中的跨文化对话,揭示中国 建筑实践中的跨世纪连贯性,并对全球性建筑技术的探索和设计创作中本土身份之间的关系进行进一步地诠 释。文章指出本次展览是对中西现代建筑“百年对话”主题的一次有意义的深入扩展性研究,并提出了中西建 筑文化交流这一宏观话题进一步研究的可能方向。  相似文献   
7.
Weanling male white rats were fed a diet containing a commercially available breakfast cereal. In 28 days they developed a mild anemia coupled with an increased amount of iron in the liver. In parallel work, this same diet was supplemented in a factorial fashion with casein, iron, copper and zinc. The zinc had no effect. Copper supplementation increased the hemoglobin level. Casein decreased liver iron. The copper and casein, when fed together, produced results approaching normal control levels. Supplementation of the diet with additional iron did not increase the hemoglobin or hematocrit but it did further increase iron storage in the liver. It is suggested that cereal enrichment programs might do well to consider copper and protein rather than focus total attention on additional iron and zinc.  相似文献   
8.
Nat Oppenheimer , principal of structural engineers Robert Silman Associates, is a dissenting voice among the advocates of building information modelling (BIM) - an enthusiastic sceptic. Could the quest for integration be leading towards oversimplification rather than customisation and differentiation? Even towards the sort of standardisation adopted with LEED ratings in the quest for sustainability? Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
9.
This paper examines the background, history, and results of multiple investigations associated with pyrite-based expansive soils spanning almost 40 years in conjunction with a private elementary school located in western Pennsylvania. The school was initially designed in 1960. Original construction was completed in September 1961 and the first signs of distress, which were primarily related to slab heave, were reported in early 1962. One wing of the school, a 1965 classroom addition (1965 addition) with different structural and foundation systems, did not experience any expansive soil-related damages and served as a valuable comparison throughout multiple subsequent investigations. Pyritic soil material in the subgrade in conjunction with oxygen-rich groundwater was determined to be the cause of soil movement and building distress. Expansive soil-related problems at the school continued for decades despite an investigation, civil court action, and judgment in the late 1960s followed by a remediation program in the 1970s and 1980s. Following a second round of investigations and litigation in the late 1990s, all of the original classroom, office, and gymnasium building sections, with the exception of the 1965 addition, were demolished in late 2000 and early 2001 based on safety concerns and economic evaluation. Investigation and monitoring to confirm subgrade conditions continued throughout the demolition process. As a part of this paper, the history of this case dating back to one of the early identifications of pyrite as an expansive element of concern in building construction, including one of the earliest comprehensive identifications of the complete chemical-microbiological oxidation process is presented. The initial 1960s investigation and conclusions are identified as well as the series of engineering, procedural, and construction errors that took place during and after the first remediation process that led to ongoing soil expansion and structural damage, including misguided actions and misunderstandings that complicated and delayed a final resolution in this case. Today, the industry is more familiar with the potential for pyrite-related construction problems, nevertheless, the paper incorporates lessons learned for avoiding problems and in particular, the procedural failures that led to the eventual need to abandon and demolish the school facility.  相似文献   
10.
As the world teeters on the verge of environmental collapse, landscape architecture has taken on a new significance offering a longed-for sanctuary for our increasingly urbanised lives. Here, in his introduction to the issue, guest-editor Michael Spens explains how by taking its impetus from land art, landscape architecture, as an expanded field, transcends the conventional confines of site. This renders it possible to read architecture ‘as landscape, or as non-landscape, as building becomes non-site’ and the ‘site indeed materialises as the work per se’. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
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