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1.
In this study, the crowd has been investigated and analyzed in waiting areas in large general hospitals in China in order to find the rules the variations of sound environment with the change of crowd. The field investigation, questionnaire, field-testing and computer simulation have been adopted. The results show that: the social/demographic characteristics of staff and patients are not significantly related to the satisfaction evaluation of sound environment; there is a significant correlation between the population density and LAeq of the background noise in waiting areas; when population density is 0, the LAeq of background noise is not 0 in waiting areas; the loudspeaker should be set in the waiting areas. Loudspeaker arrangements should be integrated into the ceiling lamp or construct facilities along the depth direction of the layout, and the two adjacent speakers recommended distance should be controlled at about 4 m. If the population density is controlled in the reasonable range, and sound absorption, noise reduction processing and electronic queuing system are adopted, sound environment of waiting areas will be built with noise interference relatively small in different population densities.  相似文献   
2.
目的分析研究多年冻土区青藏铁路在列车动荷载作用下路基的稳定性及振动衰减规律.方法选取青藏铁路北麓河段三个典型试验断面,在春季进行了列车荷载作用下的路基动力响应现场试验,采集路基、边坡、道床3处振动数据,统计计算了青藏铁路客车与货车行驶时路基振动的最大和平均加速度幅值,对实测数据进行了功率谱分析.结果路基上货运和客运列车的竖向最大加速度分别为2.2132m/ss^2和2.0004m/ss^2,对应的平均加速度分别为0.1495m/s^2和0.1143m/ss^2,道床上的振动明显减小.在T28次客运列车的作用下,对于断面Ⅲ,C3测点在振动频率为25Hz、38Hz、46Hz,55Hz出现峰值,能量集中在18~53Hz.边坡C4测点振动能量集中在20—65Hz,C5测点的优势频段为20—80Hz.结论路基上货运列车的振动比客运列车振动大,同一断面竖向衰减速度大于横向,素土路基各方向衰减小于块石路基,下一测点加速度峰值大致减小为相邻上一测点的1/10.  相似文献   
3.
This study proposes usability principles for the user interfaces (UI) design of complex 3D parametric architectural design and engineering tools. Numerous usability principles have been developed for generic desktop or web applications. The authors tried to apply existing usability principles as guidelines for evaluating complex 3D design and engineering applications. However, the principles were too generic and high-level to be useful as design or evaluation guidelines. The authors, all with more than 10 or 30 years of experience with various CAD systems, selected and reviewed 10 state-of-the-art 3D parametric design and engineering applications and captured what they thought were best practices, as screenshots and videos. The collected best practices were reviewed through a series of discussion sessions. During the discussion sessions, UI design principles underlying the collected best practices were characterized in the line of existing UI principles. Based on the best practices and the derived common UI principles, a new set of refined and detailed UI principles were proposed for improving and evaluating 3D parametric engineering design tools in the future.  相似文献   
4.
G-N系统是基于P2P模式构建一种拓扑结构,采用节点自适应算法,更好地处理节点与其相邻节点之间的关系,并能够充分利用节点的异构能力,维持更多的连接,获得更多的相关资源。  相似文献   
5.
High pressure solidification rules of Al-Mg alloy needs to be discussed further for its wide range of application. Mierostructures and phases of Al 25wt% Mg alloy solidified at 4 GPa were studied by optical microscope, X-ray diffractmeter, energy dispersive X-ray speetroscopy and transmission electron microscnpy (TEM). The mierostructure evolution mechanism of Al-25Mg alloy under high pressure was analyzed. The result shows that the alloy consists of α-Al phase and AI3Mg2 phase under normal pressure. However, only Al12 Mg17 phase forms without AI3Mg2 phase at 4 GPa. In addition, Mg concentration in α-Al phase increases and that of the lattice constant also increases. The α-Al dendrite presents the broken arms under normal pressure, after high pressure solidification, the morphology of the dendrite tends to integrate and the size of the dendrite arms decreases.  相似文献   
6.
We have investigated the low-temperature behavior of the optical and magneto-optical properties of (Bi, Gd, Al)-substituted yttrium iron-garnet films that are either single or microresonator, i.e. sandwiched between two dielectric Bragg mirrors. It was shown that the magneto-optical properties of the microresonators with a magnetic film core are mainly determined by the properties of the constituent magnetic films. Special attention was paid to the compositions possessing magnetic compensation temperatures. The phenomenon of the temperature hysteresis was found and discussed for several samples. This testifies the fact that the magnetic moment reorientation in a magnetic field occurs by the full cycle of the first-order phase transitions “collinear phase – non-collinear phase – collinear phase”. The Faraday hysteresis curves at around magnetic compensation temperatures are demonstrated to be very informative concerning composition of a sample. In particular, the hysteresis curves measured for the magnetic films on the garnet substrates showed bursts that indicates formation of a transition layer.  相似文献   
7.
Two new compounds based on mono copper(II)-substituted phosphomolybdate, [Cu4(tea)6(H4PMo11CuO39)(PMo12O40)]2·33H2O (1) and [Cu3(tea)6(H2O)2(H2PMo11CuO39)2]2·30H2O (2) (tea = 2- [1,2,4]triazol-4-yl-ethylamine), have been synthesized under hydrothermal conditions. Compound 1 owns tetra-nuclear clusters [Cu4(tea)6], linking a pair mono copper(II)-substituted and saturated Keggin anions to form a 2D structure. Compound 2 contains tri-nuclear clusters [Cu3(tea)6], fusing four mono copper(II)-substituted anions to construct a discrete four-membered cycle structure.  相似文献   
8.
针对道路车道因事故被占用时对该路段通行能力的影响问题,利用Excel处理数据进行了分析,通过统计得到数据,分析同一横断面交通事故所占车道不同对该横断面实际通行能力影响的差异,对排队车辆长度问题,用线性规划与最小二乘法分别构建模型,求出道路实际通行能力、上游车流量、时间与排队车长度间的关系,得出较为合理的数学模型,并用函数拟合说明该模型的可行性。  相似文献   
9.
从寒地住区建筑主体的节能布局、建筑体型选择、围护结构的设计、新技术的运用等方面入手,深入研究了寒地住区建筑节能问题的有效解决方法,并指出了寒地住区建筑未来的发展方向。  相似文献   
10.
张海鸿 《山西建筑》2013,(36):92-93
对工业管道概念及工业管道工程管理重要性进行了论述,结合工作经验提出了工业管道工程施工管理的要点,并进行了阐述和分析,对提高施工质量、保障工业管道安全运行具有重要意义.  相似文献   
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