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961.
962.
文章通过对从点到点——上海民间自发的旧建筑改造与利用实例的分析,说明这是旧建筑改造利用的重要方式,应引起足够的重视和关注,同时指出政府在旧建筑改造利用中的角色定位。 相似文献
963.
云南老厂矿区无烟煤瓦斯含量高、衰减性强、透气性系数低、瓦斯难于抽采,采用常规顺层钻孔和普通顶板高位钻孔方式难以解决上隅角瓦斯和回风流瓦斯超限问题,而采用顶板高抽巷方式面临工程量大、经济成本高、工期长等问题。通过使用定向大直径钻机施工高位定向长钻孔替代顶板高抽巷的方法,利用FLAC3D数值差分软件分析煤层顶板断裂带高度。结果表明:老厂矿区8#煤层垂向18~35 m区域为最佳抽采层位,使用高位定向长钻孔对8#煤层顶板裂隙抽采后平均抽采瓦斯浓度(甲烷体积分数,下同)可达16%左右,平均抽采瓦斯纯流量为9.05 m3/min,工作面上隅角瓦斯浓度控制在0.60%以下,回风流瓦斯浓度控制在0.40%以下,与采用高抽巷方法的瓦斯抽采效果相当,验证了高位定向长钻孔“以孔代巷”技术的合理性和可行性,可为云南老厂矿区无烟煤瓦斯抽采提供参考。 相似文献
964.
针对矿井风网解算中待掘巷道摩擦阻力系数难以准确实测赋值的问题,构建了巷道摩擦阻力系数BP神经网络预测模型,以双柳煤矿各类巷道摩擦阻力系数实测数据作为训练样本进行学习训练,使预测模型的期望误差达到0.000 1以下。利用该模型对尚未贯通的23(4)13回采工作面的巷道摩擦阻力系数进行预测,将预测结果代入基于斯考德—恒斯雷法风网解算方法构建的双柳煤矿通风网络解算模型中,分别对23(4)13回采工作面贯通后备用阶段和回采阶段全风网风量分布进行了解算,解算结果与现场实测结果之间相对误差小于8%。研究结果表明,利用基于BP神经网络算法的巷道摩擦阻力系数预测模型对待掘巷道摩擦阻力系数进行预测赋值,能够实现风网风量的准确解算。 相似文献
965.
Considering the mixture after muon-catalyzed fusion(μCF) reaction as overdense plasma,we analyze muon motion in the plasma induced by a linearly polarized two-colour laser,particularly,the effect of laser parameters on the muon momentum and trajectory.The results show that muon drift along the propagation of laser and oscillation perpendicular to the propagation remain after the end of the laser pulse.Under appropriate parameters,muon can go from the skin layer into field-free matter in a time period of much less than the pulse duration.The electric-field strength ratio or frequency ratio of the fundamental to the harmonic has more influence on muon oscillation.The laser affects little on other particles in the plasma.Hence,in theory,this work can avoid muon sticking to α effectively and reduce muon-loss probability in μCF. 相似文献
966.
Victoria Aragon Stephanie Gauthier Peter Warren Patrick A. B. James Ben Anderson 《Building Research & Information》2019,47(4):375-393
ABSTRACTOccupancy patterns are necessary to estimate energy demand and evaluate thermal comfort in households. Because of this, many European countries are developing representative domestic schedules to replace outdated criteria. This paper evaluates the state of knowledge of UK domestic occupancy patterns and develops new domestic occupancy profiles for England. The presented research (1) characterizes methods for collecting occupancy data and inferring patterns; (2) identifies and assesses the quality of categories of occupancy patterns used in building simulation; and (3) develops updated occupancy profiles. A systematic scoping review identified social and monitoring surveys as the most deployed data-collection methods. A systematic literature review also established that the occupancy categories most frequently used in UK building simulation are (a) a family with dependent children where the parents work full time; and (b) a retired elderly couple who spend most of their time indoors. The interview sample from the English Housing Survey 2014–15 was used to map household typologies. Results show that categories (a) and (b) combined amount to only 19% of England’s households, which suggest models are over-reliant on these groups. Considering this result, the paper develops occupancy patterns for England derived from 2015 UK Time Use Survey diaries for each household typology previously identified. 相似文献
967.
No authorship indicated 《Canadian Metallurgical Quarterly》2010,65(8):718
The American Psychological Association 2010 Award for Distinguished Scientific Early Career Contributions to Psychology was awarded to Stanley F. Floresco, for his outstanding and innovative research on neural mechanisms linking brain activity to critical cognitive functions including risk-based decision making, cognitive flexibility, working memory, and other aspects of executive function. His novel findings form an empirical base for understanding how neural pathology may underlie aspects of psychotic behavior and as such validate neuropsychopharmacological approaches to mental ill health. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
968.
969.
Niccols Alison; Milligan Karen; Sword Wendy; Thabane Lehana; Henderson Joanna; Smith Ainsley; Liu Jennifer; Jack Susan 《Canadian Metallurgical Quarterly》2010,24(3):466
To examine the impact of integrated treatment programs (those with substance use treatment and pregnancy-, parenting-, or child-related services) on maternal mental health, we compiled a database of studies of integrated programs published between 1990 and 2007 with outcome data on maternal mental health. There were 18 cohort studies, 3 randomized trials, and 2 quasi-experimental studies. Of the five studies comparing integrated to nonintegrated programs, three studies provided enough information to allow for them to be combined in a meta-analysis. The average effect size was 0.23 (95% CI = 0.15 to 0.31, SE = 0.04), p Q = 5.66, p = .059. This meta-analysis is the first systematic quantitative review of studies evaluating the impact of integrated programs on maternal mental health. Findings suggest that integrated programs may be associated with a small advantage over nonintegrated programs in improving maternal mental health. This review highlights the need for further research with improved methodology, study quality, and reporting to improve our understanding of how best to meet the mental health needs of mothers with substance abuse issues. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
970.
A number of critiques have been published drawing attention to the gaps in research methods applied to issues surrounding homelessness and service utilisation in Britain. This paper discusses the use of social identity, a theory drawn from the field of applied social psychology, and synthesises it with the pathways model, thereby providing a framework to further explore service utilisation. The synthesised framework was used to predict the uptake of outreach services in a prospective study of 121 homeless people in a major UK city. In general, homeless people's use of intervention services was affected by the extent to which they identified with the support services themselves. The study demonstrates the central role of social identity in understanding service utilisation patterns, and shows the importance of applying fresh techniques to fine-tune our understanding of uptake in the long term. 相似文献