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1.
The constructive analysis of Madrid's old timber-framed collective courtyard buildings, whether demolished, preserved intact, or enlarged, has achieved the dating of relevant case studies. New parameters established in this study set a chronology based on front sector original projects: old (1737–1788), pre-modern (1788–1847) and modern (1847–1892). The on-site inspection and archival research point to ongoing misleading construction in the historic Southern area. Some modern corralas erected on top of pre-existing buildings confirm the initial hypothesis. First dimensioning rules for new façades and the stability required in old ones before adding new storeys, maintaining the original masonry or double-layered system, are discovered. Undated buildings suggest their possible origin a la malicia and a later transformation into transitional corralas. Finally, an analysis of the demolished courtyards narrows down the dating and points to new conjectures in some preserved by showing their uneven layout, old features, and structural discordances in each sector.  相似文献   
2.
This paper assesses building integrated photovoltaic (BIPV) installation parameters based on the profit generated by a photovoltaic system. It takes into consideration a home building case study and it investigates its monthly energy demand based on a specific location and a typical occupancy. The capability of a photovoltaic (PV) system to generate more profit occurs when solar intensity is maximum while the electric energy price is at its highest rate. The paper traces a framework that encompasses different aspects such as energy demand, energy price, and solar intensity. This framework identifies profit alternatives according to different installation parameters. A tool that predicts a PV installation hourly electric energy production is developed. The profit generated is simulated for home buildings located in Beirut (Lebanon) and Xihua (China), both at 33.8° latitude north. The paper highlights a new approach for BIPV installations, taking into account weather conditions, energy demand, and electric energy utility rates.  相似文献   
3.
环境中氚和碳-14   总被引:4,自引:0,他引:4  
方栋  李红 《辐射防护》2002,22(1):51-56
本文介绍了加拿大恰克河实验室有关氚和碳-14在环境中行为和评价的研究。  相似文献   
4.
Based on an idea introduced by Benjamin and Cornell (1970. Probability, statistics and decision for civil engineers. New York: McGaw Hill) and previous works by the authors it is demonstrated how condition indicators may be formulated for the general purpose of quality control and for assessment and inspection planning in particular. The formulation facilitates quality control based on sampling of indirect information about the condition of the considered components. This allows for a Bayesian formulation of the indicators whereby the experience and expertise of the inspection personnel may be fully utilized and consistently updated as frequentistic information is collected. The approach is illustrated on an example considering a concrete structure subject to corrosion. It is shown how half-cell potential measurements may be utilized to update the probability of excessive repair after 50 years. Furthermore in the same example it is shown how the concept of condition indicators might be applied to develop a cost optimal maintenance strategy composed of preventive and corrective repair measures.  相似文献   
5.
张玉华  赵健 《人民长江》1994,25(12):31-35
三峡库区湖北宜昌、秭归、兴山、巴东四县幅员面积11589.3平方公里,总人口数166.02万人,三峡水库形成后,淹没土面积74.47平方公里,涉及8.94万人,规划农业生产安置2.8万人。本文以四县土地资源利用现状主和环境容量的分析为基础,进行三峡库区移民安置对水土流失的影响评价,论证综合开发利用水土资源,水土保持与开发性移民相结合,是扩大库区人口环境容量的必由之路,研究制订出移民安置与水土资源的  相似文献   
6.
阜阳电厂粉煤灰综合利用可行性研究   总被引:3,自引:0,他引:3  
结合阜阳地区实际情况,从目前成熟的粉煤灰利用途径中,选择制水泥、建粉磨站、生产非煅烧粉煤灰轻骨料、轻质小砌块,以及筑路回填、灰场种植等处理利用项目,达到节约土地并获得好的经济效益和环境效益  相似文献   
7.
硫化矿石氧化性的实验室综合评判   总被引:5,自引:0,他引:5  
李孜军  吴超  周勃 《铜业工程》2003,(1):40-42,25
探讨了一种硫化矿石氧化性综合评判的新方法 ,并将该方法应用于矿山实际 ,得到了准确的评判结果。该项成果对于硫化矿石自燃防治理论与技术的研究具有很高的参考价值。  相似文献   
8.
The Land Transport Authority of Singapore has a continuing program of highway bridge upgrading for refurbishing and strengthening bridges to allow for increasing vehicle traffic and increasing axle loads. One subject of this program has been a short-span bridge taking a busy main road across a coastal inlet near a major port facility. Experiment-based structural assessments of the bridge were conducted before and after upgrading works including strengthening. Each assessment exercise comprised three separate components: (1) a strain and acceleration monitoring exercise lasting approximately one month; (2) a full-scale dynamic test carried out in a single day without closing the bridge; and (3) a finite-element model updating exercise to identify structural parameters and mechanisms. This paper presents the dynamic testing and the modal analysis used to identify the vibration properties and the quantification of the effectiveness of the upgrading through the subsequent model updating. Before and after upgrade, similar sets of vibration modes were identified, resembling those of an orthotropic plate with relatively weak transverse bending stiffness. Conversion of bearings from nominal simple supports to nominal full fixity was shown via model updating to be the principal cause of natural frequency increases of up to 50%. The utility of the combined experimental and analytical process in direct identification of structural properties has been proven, and the procedure can be applied to other structures and their capacity assessments.  相似文献   
9.
甘勤 《金属矿山》2003,(2):62-64
简述了攀钢含铁尘泥的基本特性、攀钢含铁尘泥利用技术现状及存在的问题。根据目前国内外钢铁企业含铁尘泥综合利用技术的动态、经验,并结合攀钢的实际情况,提出了攀钢含铁尘泥利用技术的发展方向。  相似文献   
10.
对选矿废水综合利用的探讨   总被引:4,自引:0,他引:4  
刘敏婕 《中国钼业》1995,19(3):43-46
通过对金堆城钼业公司选矿废水再用于选矿作业的选矿试验,证明选矿废水循环利用是可行的,既提高了选矿浓度,又减少了对环境的污染,经济和社会效益显著。  相似文献   
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