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Spaces without northerly orientations have an impact on the ‘energy behaviour’ of a building. This paper outlines possible energy savings and better performance achieved by different zenithal solar passive strategies (skylights, roof monitors and clerestory roof windows) and element arrangements across the roof in zones of cold to temperate climates typical of the central and central-southern Argentina. Analyses were undertaken considering daylighting, thermal and ventilation performances of the different strategies. The results indicate that heating, ventilation and lighting loads in spaces without an equator-facing facade can be significantly reduced by implementing solar passive strategies. In the thermal aspect, the solar saving fraction reached for the different strategies were averaged 43.16% for clerestories, 41.4% for roof monitors and 38.86% for skylights for a glass area of 9% to the floor area. The results also indicate average illuminance levels above 500 lux for the different clerestory and monitor arrangements, uniformity ratios of 0.66–0.82 for the most distributed arrangements and daylighting factors between 11.78 and 20.30% for clear sky conditions, depending on the strategy. In addition, minimum air changes rates of 4 were reached for the most extreme conditions. 相似文献
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清代皇家园林规划设计控制的量化研究——以圆明三园、清漪园为例 总被引:1,自引:0,他引:1
本文通过量化分析探索了清代皇家园林规划设计的控制规律及相关理论。 相似文献
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文章通过对焦作煤田大煤顶分层沿空留巷大量观测资料的分析,闸明在大煤既定的围岩特征和留巷所采用的支护方式条件下,“支驾——围岩”这一对相互作用的力学力系,在采场支承压力作用下趋向平衡时所呈现的矿压规律。从而分析留巷所采用的梯形“工”字钢支架,巷内架设抬棚的支护方式的合理性。 相似文献
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我国古典园林论著,现在常见的有计成的《园冶》、李笠翁的《一家言居室器玩部》以及明人程荩臣的《清闲供》书中的《小蓬莱》共三种,其余零星散见于古人笔记的不计。《清闲供》一书,计有不同内容的短篇十四篇,《小蓬莱》谈造园艺术,只是书中的一项内容,全文短。《清闲供》毫无现实的积极意义,经过时代的淘汰更失去其效用,成为了糟粕。 相似文献
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概述了汽车顶内饰用热塑性聚氨酯硬质泡沫塑料进展状况,介绍了硬泡及顶内饰成型方法,对影响该硬泡性能的一些因素进行了讨论。指出该顶内饰已批量生产。 相似文献
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随着城市的发展,城市积水造成了越来越严重的问题.解决问题的关键就是分析超标降雨下的城市积水风险,以指导近期应急排水预案以及远景城市雨水系统改造方案的制定.由于北京市降雨量年内分配很不均匀,汛期暴雨又多表现为局地短历时的大暴雨甚至特大暴雨,造成城市道路(特别是立交桥区)积水问题频发,严重影响城市交通.在此背景下,从保障奥运安全召开的角度出发,以奥运中心区为研究对象,收集整理奥运中心区雨水系统各组成部分相关资料,建立奥运中心区雨水系统数据库,建立奥运中心区雨水系统模型,对超标降雨条件下奥运中心区的可能积水风险进行了分析,并以此为基础进行对策研究和实施效果评价. 相似文献
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《矿业科学技术学报(英文版)》2017,27(1):37-41
In underground mining, machine design is predominantly dictated by mine conditions and individual customer desires. In partnership with Foresight Energy, J. H. Fletcher Company was tasked to design and manufacture a new roof bolting machine with six independent drilling apparatus on board capable of drilling and bolting the roof and ribs with material handling. The objective was to produce a machine capable of drilling and installing six bolts simultaneously with a limited number of operators. The goal of the mine is to decrease the time to bolt a cut to improve the safety level of the current roof bolting method, improve efficiency and to improve the bottom line cost of entry development. The customer wanted four drills at the front of the machine dedicated to installing roof bolts and then another two drills behind them dedicated to rib bolts. This dictated the requirement of latched controls, which would allow the operator to start drilling one hole and then latch the controls to be able to move on to the next.The result of the design is a machine with a single platform and six independent masts with drillheads:four masts strictly for drilling and installing roof bolts on the front of the platform and two masts on the back of the platform for rib bolts. The controls at each operator's station include a latch control for drilling. The six-head roof bolter allows fewer operators to drill and install roof and rib bolts, which in turn lowers the miners' roof exposure per cut. This design reduces the operator's exposure from the inherent pinch points and rotary hazards once he has engaged the latch drilling. Therefore, the machine will help to decrease the time to bolt a cut, improving productivity while enhancing the ability to operate the machine safely. 相似文献
10.
《矿业科学技术学报(英文版)》2016,26(2):261-265
Based upon characteristic movement features of the overlying strata in solid backfill mining and in-situ observations,an associated model representing a roadway support system has been developed.Based on the Winkler foundation and beam model,the current study presents a static analysis of the model,thus permitting acquisition of a theoretical formula pertaining to roof convergence.Through use of working face 6304-1(Jisan Colliery) as the research setting,the association between roof convergence magnitude and both packwall strength and width have been elucidated.Based upon observed conditions at the working face,realistic packwall parameters have been formulated,with numerical simulation results and field application results indicating that design parameters garnered from the developed formula successfully adapted to local geological movement and deformation.Accordingly,roadway deformation was shown to be within the permissible range,thus satisfying mine production requirements.The proposed method in the current study may give a design basis for pack design in the context of SBM under similar conditions. 相似文献