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The influenfial factors of stratification plane to smooth blasting are studied according to the ti eory of smooth blasting and the anslysis of static stress. The results show that the angle p between the maximum principal plane and the rertical line of stratification plane has some influence on the fracture of rock masses. 相似文献
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This article puts forward a 3 Layers Model for the communication between embedded system and PC. It is based on the speciality of them and the TCP/IP model. The model defines the communicate process of embedded system to be three layers: Transport Layer, Control Layer and Application Layer. Each layer serves for its higher-up. It can keep the efficiency and credibility of the communicate process and the authors prove and analyse that in the article. the concept of the model is also suitable for Bluetooth, IrDA and other kinds of communication about embedded system. 相似文献
24.
Chen Qigao Feng Ya 《保鲜与加工》1993,(1)
This paper analyses the thermal moist characteristics of the hull layer beside an air layer at lower temperature in an envelope for a cold storage and presents a new method of waterproof by air layer. With test data from engineering practice, the theory on the barrier of self moisture proof at the surface sublayer of the hull layer in an attic on a cold storage is proven. The dried zone about three phase point is confirmed. It is a new knowledge for thermophysics on thermal design of a cold storage with an optimum thermal performance. 相似文献
25.
紫坪铺水利枢纽引水系统取消厂前伸缩节研究 总被引:3,自引:0,他引:3
结合紫坪铺水利枢纽工程的实际情况,采用三维有限元方法对该工程发电引水系统取消伸缩节的可行性进行了研究。计算结果表明,主厂房上游永久分缝处以一段垫层管代替常规伸缩节,结构位移和应力完全可以满足使用要求,从而达到了取消伸缩节、节省工程投资的目的。 相似文献
26.
南方平原灌区渠道防渗工程规划方案决策分析 总被引:1,自引:1,他引:1
针对目前灌区防渗渠道规划的局限性,引入价值工程的概念,并根据南方平原地区灌区的特点,应用计算机模拟技术,通过对渠道的衬砌费用和节水量的模拟计算,得出更为切合实际的灌区防渗渠道投资效益评价指标,从而确定防渗工程的最优布局以及工程实施的先后顺序。 相似文献
27.
U形混凝土衬砌渠道断面的一种优化设计方法 总被引:2,自引:1,他引:2
齐宝全 《中国农村水利水电》1996,(8)
明渠衬砌U形断面渠道设计中仍存在一定的缺陷。以总费用(或投资)最小为目标,建立了U形渠道断面优化设计模型,采用比例系数法,将优化设计数学模型简化,用PC—1500计算机求解了衬砌U形断面渠道在工程费用较小时的断面设计参数。 相似文献
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行星边界层参数化方案(PBL)对天气气候和大气环境的模拟与预报具有重要影响.通过基于单柱模式(SCM)的乌鲁木齐单点理想实验,以及新疆2019年8月15—18日的一次降水天气过程的模拟检验及诊断分析,研究了YSU、ACM2、BOULAC、GBM、MYJ和QNSE 6种常用的PBL参数化方案模拟的大气比湿、位温等气象要素... 相似文献
30.
Bacteria in desert soil have unique phylogeny and important ecological functions, and theirresponses to changes in precipitation need further attention. However, relevant studies have mainlyfocused on the surface soil, and studies on the responses of bacteria at different soil depths to variationsin precipitation are rare. Thus, we used 16S rDNA high-throughput sequencing to investigate the changesin soil bacterial distribution along a mean annual precipitation gradient (50–150 mm) in the Alxa Desert,China, and compared the variation characteristics in the surface soil layer (0–10 cm) and subsurface soillayer (10–20 cm). Results showed that soil bacterial communities significantly changed along theprecipitation gradient in both soil layers. However, the subsurface soil layer could support bacterialcommunities with higher diversity and closer internal relationships but more internal competition than thesurface soil layer. Additionally, compared with the surface soil layer, variations in diversity andco-occurrence patterns in the subsurface soil layer were more in line with the changes in the mean annualprecipitation, while bacterial community structure was less variable in the subsurface soil layer. Comparedwith the mean annual precipitation, soil moisture had little influence on the structure and diversity of soilbacterial community but had a high correlation with intercommunity connectivity. Therefore, soilmoisture might play a complex role in mediating environmental conditions and soil bacterial communitycharacteristics. Due to the different responses of surface and subsurface soil bacteria to the changes inprecipitation, it is necessary to distinguish different soil layers when predicting the trends in desert soilbacterial conditions associated with precipitation, and prediction of subsurface soil bacteria may be moreaccurate. 相似文献