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951.
在新意法中,利用掌子面的稳定情况来判断隧道是否需要采取超前加固措施。文中依据摩尔库伦准则,对隧道开挖后掌子面的弹塑性状态进行研究,得出掌子面处于弹性状态的隧道最大埋深,并通过数值模拟,对得到的结果进行了验证。  相似文献   
952.
应用一套模态测量分析系统对某V6柴油机组件进行了模态测试 ,获得其模态参数及振型 ,为发动机结构改进设计提供试验依据  相似文献   
953.
该文以无锡市蠡湖大道-周新路路口为例,介绍可变车道在信号交叉口的应用方法,包含可变车道检测器的布置、信号灯控制机理,以及交通安全配套设施的设置等,最后通过饱和度指标评价可变车道方案的实施效果。结果显示,实施可变车道能够合理分配道路资源、缓解路口通行压力、减小车辆排队长度,对于潮汐车流明显的城市,具有推广的意义。  相似文献   
954.
通过对农村公路管理养护现状及存在问题的剖析,以及农村公路养护模式的经验探讨,根据农村公路发展面临的形势和要求,研究构建山东省农村公路养护管理体制结构与运行机制。  相似文献   
955.
Lane closures due to highway work zones present many challenges to the goal of ensuring smooth traffic operations and a safe environment for both drivers and workers. Late merge behavior at a work zone closure is a dangerous behavior that impacts the traffic conflicts upstream of work zone closures. This paper analyzes the safety impacts of using a signalized lane control strategy at the work zone merge points. To achieve the objective of this research, a field study has been conducted at a highway work zone to collect traffic and driver behavior data, and a two-stage, simulation-based approach is used to analyze the safety impacts of implementing a signalized lane merge control strategy at the studied work zone. In the first stage, micro-simulation models are developed and calibrated based on field data to generate vehicle trajectories. In the second stage, the U.S. Federal Highway Administration’s Surrogate Safety Assessment Model is employed to identify potential conflicts under different traffic conditions. The paper concludes that a proposed signal control device could significantly reduce lane-change conflicts at work zone merge points. In addition, recommendations on the signal cycle length and timing splits are provided.  相似文献   
956.
Organic photovoltaic (OPV) cells and organic light-emitting diodes (OLEDs) are energy harvesting and generation devices that have attracted great attention these years because of their low costs, thin film structures, flexibility and environment-friendly manufacturing processes. For such thin film devices, photon management methods that increase the light absorption of OPV cells and the light extraction from OLEDs are highly desirable. Here, we report the experimental efforts to fabricate geometrically tunable and spontaneously formed nano-wrinkle structures with large areas, and the theoretical results on photon management with the nano-wrinkles.  相似文献   
957.
李琦 《中国水运》2007,5(4):163-164
“循环经济”已经融入中国主流经济概念当中,将对中国未来经济发展产生深远的影响。本文就我国循环经济立法的现状和趋势进行了分析,并对我国生产企业如何通过构建自身的逆向物流体系来应对循环经济立法趋势提出了建议。  相似文献   
958.
应用抗原特异性玫瑰花结试验对比研究HBV-TF、N-TF及TMP的生物活性及抗原特异性。实验发现经HBV-TF作用的绵羊淋巴细胞与HBsAg包被的绵羊红血球形成的抗原特异性玫瑰花结阳性率最高,为4.5%,而经N-TF及TMP作用的绵羊淋巴细胞仅形成极少的玫瑰花结,分别为0.35%和0.33%与HBV-TF作用组相比有非常显著的差异(P<0.01)。  相似文献   
959.
智力低下儿童的视觉—运动综合能力发育   总被引:1,自引:0,他引:1  
用Beery’s视觉-运动综合(VMI)发育测验对60名智力低下病儿作了评估,全部病儿的VMI发育的年龄等值均落后于实际年龄,落后15%~62%。与韦氏智力量表总智商之间的相关系数为0.5225(P<0.001)。Beery’sVMI发育测验是国外广泛应用的儿童发育评估工具,对智力低下、学习困难等发育疾病的诊断很有帮助,值得推荐。  相似文献   
960.
During the installation operations of underwater structures, offshore structures such as semisubmersibles, the steady nonlinear hydrodynamic force due to the ocean current, the tidal current, and the hydrodynamic interaction between structures are regarded as major disturbances. Generally, it is difficult and very expensive to collect information about these disturbances in advance, although such knowledge would be important and necessary for precise installation. Because of this situation, we have proposed a learning tracking controller (LTC) for automated tracking/docking operations of offshore structures. The LTC can be operated without any information about current, and can be applied to the installation problem of flexible structures whose flexibility cannot be ignored. In order to confirm the effectiveness of the LTC, basin tests were carried out using experimental models with an unknown current. Two types of basin experiment were executed using an ultrasound ranging system and thrusters. One was trajectory tracking of a semisubmersible, and the other was the precise mating of flexible underwater structures. In both cases the LTC showed good performance, and in the latter case in particular, two flexible models were successfully made to track the given trajectory and dock to the docking targets with an accuracy of ±5 mm, after the trajectory had been tracked six to seven times for learning purposes. No elastic responses were excited in the flexible model. Received for publication on Dec. 1, 1999; accepted on March 13, 2000  相似文献   
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