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1.
针对不同强度准则计算松动圈的适用性问题,基于围岩弹塑性理论,采用统一强度理论推导了巷道围岩松动圈理论计算公式。依托实际工程,采用Mohr-Coulomb准则、Hoek-Brown准则和统一强度理论对巷道围岩松动圈厚度进行理论计算。将理论计算结果和现场测试结果进行对比,发现基于Mohr-Coulomb准则计算松动圈厚度大于现场测试结果,基于Hoek-Brown准则计算松动圈厚度小于现场测试结果,同时二者的理论计算厚度与现场测试结果相差较大。而统一强度理论计算松动圈厚度和现场测试结果比较接近。因此,统一强度理论适用于巷道围岩松动圈理论计算。  相似文献   

2.
平台印机转动惯量与制动力矩的计算与测试   总被引:1,自引:0,他引:1  
介绍对某平台印刷机等效转动惯量和制动力矩的理论计算和测试试验的方法和结果.内容包括运动分析,等效到制动轴的整机等效转动惯量计算,在各种预定时间内制动停止所需的制动力矩计算以及实际测试试验.理论计算与测试所得结果相当吻合.  相似文献   

3.
考虑各向异性的电缆地层测试产能预测方法   总被引:1,自引:0,他引:1  
为提高电缆地层测试对各向异性储层产能评价的精度,避免应用DST测试产生的高测试成本,利用自行设计的多探头电缆地层测试仪器和解释模型,求取既定方位的储层平面上正交方向的两个渗透率,利用基于地质统计学的变差函数分析方法分析储层实际主渗透率方向,结合矢量化渗透率计算模型,计算实际储层的主渗透率和垂直主渗透率方向的最小渗透率,给出通过电缆地层测试获得储层实际平面渗透率各向异性的方法.结合椭圆形边界油藏产量计算模型,给出渗透率各向异性地层电缆地层测试产能预测方法.电缆测试方法计算的产能结果与DST测试结果基本吻合.  相似文献   

4.
基于模拟试验的测试性评估方法研究   总被引:1,自引:0,他引:1  
研究了测试性故障注入及数据处理方法,提出测试性故障模式分析方法、样本量选取与分配原则等.考虑样本覆盖率与样本量,提出一种将模拟试验与自然样本相融合的测试性评估方法.将模拟样本数据与自然样本数据相结合,利用复杂系统故障率数据,实现测试性故障检测率指标综合计算.最后,通过实例进行了数据分析计算.计算结果表明,该方法能有效解决测试性模拟试验和自然故障样本数据融合评估的问题.  相似文献   

5.
采用传递矩阵法对倍捻锭子的临界转速及其对应阶振型进行了理论计算,并对样件进行了模态测试以验证理论计算的准确性,结果表明理论计算值与模态测试值基本吻合。  相似文献   

6.
 以线热源理论为基础建立套管式地埋管换热器换热的简化模型,给出基于热响应试验的套管式换热器设计计算方法。以湖南省韶山市一实际工程为实例对钻孔现场进行测试,采用该方法可计算出其综合导热系数和钻孔内总热阻。同时对该工程的另一钻孔进行双U测试及计算,以此作对比分析。考察两组测试在综合导热系数、钻孔内总热阻、换热温差和换热量上的内在联系。计算结果和测试结果表明,该计算方法在套管式换热器设计上具有适用性,避开了钻孔内层层热阻的复杂计算,简化了计算过程,可为实际工程提供计算参考。  相似文献   

7.
针对二维电大尺寸对象电磁散射场的计算,提出一种电磁散射快速算法,该算法以不变性测试方程(measured equation of invariance, MEI)方法为基础,将循环卷积和测试电流跳点平均技术分别用于不同区域对应的MEI 系数,可以大大加速MEI测试方程系数的计算,提高MEI方法的计算速度,通过二维实例的仿真计算验证了这种算法的计算效率和准确度,证实了算法的有效性。  相似文献   

8.
本文采用例证的方法证明了德国克劳斯塔尔工业大学采矿方法及矿山经济研究所在建立单图片摄影测试系统中原采用的计算露天矿爆堆块度分布的体积计算方法的非正确性.并推导出一种较为精确的煤岩块度计算方法──面积计算方法.使该测试系统的测试精度达到90%以上  相似文献   

9.
文章给出关于微处理器随机测试长度的计算方法:从模块级出发或从功能级出发,由最小检测概率计算最大测试长度。并获得实验证实。  相似文献   

10.
依据汽车滑行测试相关的标准,对被测车辆进行滑行阻力分析,利用能量守恒法构建被测车辆的能量耗散关系,并从中推导出被测车辆滑行试验中的空气阻力系数;根据最新发布的汽车行业标准对被测车辆进行道路滑行测试,对采集到的滑行数据进行分析计算,得出空气阻力系数的数值解析式;以实验数据和国Ⅵ计算方法作为参照,验证所得空气阻力系数计算式的合理性。研究结果表明:基于数值计算空气阻力系数所得的道路载荷与试验测试结果相比,相对误差控制在5.4%之内,且道路载荷的数值计算结果能有效逼近试验测试结果。  相似文献   

11.
海德格尔对荷尔德林诗歌的阐释,目的是进行诗与思的对话,归根结底还是探讨存在。诗与“在”的关系,是海氏诗学框架的核心内容,诗与“在”的关系又进一步引申为艺术与真理的关系,本从真理如何被遮蔽的问题入手,试图读解海德格尔诗学的内涵。艺术是无蔽的真理显明的一种方式,诗是危机的拯救,语言是存在的家园。海德格尔对诗与在的探讨最后又转入了对语言的探讨,无法走出语言的牢笼。只有在实践中,把艺术变成为社会变革的一个因素,才可以解放被传统理性压迫的力量,显现艺术的真理,确立艺术的价值。  相似文献   

12.
Canonical Wnt/β-catenin pathway plays a central role in development, homeostasis, as well as tumorigenesis. The regulation of the pathway involves various and complicated mechanisms, including the extracellular, intracellular and endonuclear regulation. As the key component of the pathway, the Lefl/Tcfs-β-catenin complex is also the key target of regulation in the nucleus. In the current review, we are going to summarize the regulators in the nucleus which can modify the transcrip- tional activity of the Wnt/β-catenin pathway.  相似文献   

13.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

14.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

15.
信托财产是信托关系的基本要素,由于信托的特殊性,信托财产与传统民法的财产有很大区别,正确给信托财产定位,是信托业得以健康发展的核心问题。信托财产的特性在于其人格性,而这种人格性的赋予是以交易成本最小化为动因,尽管信托财产人格性设计对受益人的利益有偏袒,但从社会成本而言,其目的在于促使交易成本最小化,当然,对信托财产的人格性不能绝对化,由于利益平衡的需求,往往在特定情况下对信托财产予以人格否认。  相似文献   

16.
本文通过测量金属晶体电极表面的微分电容研究了金属电极表面在金属与水溶液界面上的吸附能力,以及金属与吸附质之间的相互作用。文中论述了多晶铜电极在(0.5-x)mNaClO_4+xmNaBr的一系列不同x值的溶液中的微分电容测量值及微分电容-电位曲线,证明了F~-和ClO_4~-离子在多晶铜电极表面是非常弱的吸附,Br~-离子在多晶铜电极表面具有特定的吸附,每条电容-电位曲线有一个凸起的峰。在峰所对应的位能值,金属表面对阴离子的吸附能力强,证实金属-吸附质之间的相互作用强,吸附的阴离子在过渡层中散射导电电子的能力也强。对于相同阴离子和金属的体系,其微分电容与吸附质的浓度、电压、溶液的pH值和表面的非均匀性等因素密切有关。研究证明,金属晶体电极表面在电解质溶液中的微分电容的变化规律类似于表面电反射信号的强弱变化规律,微分电容大小取决于金属-吸附质之间的电荷转移程度。  相似文献   

17.
阴离子表活剂压裂液是新型清洁压裂液,原油和地层水对其破胶机理与实验研究已相当充分,但气体对其破胶作用至今研究很少.为解决阴离子表活剂压裂液在压裂应用中的障碍,研究采用一套实用的实验流程,评价了天然气、氮气、二氧化碳三种常见气体对阴离子表活剂压裂液的影响.实验证明,三种不同的气体对阴离子表活剂压裂液的降粘幅度存在较大的差别,其中,二氧化碳气体对阴离子清洁压裂液降粘幅度最大,可使交联液体彻底破胶,天然气对阴离子型表活剂压裂液降粘幅度较小,氮气对阴离子压裂液的粘度几乎没有影响,氮气和天然气可以使液体泡沫化,从而有利于返排.实验结果为优化压裂设计提供了依据,可有效提高现场压裂施工成功率.  相似文献   

18.
介绍了速调管在我国的发展现状和几种不同结构的多腔速调管的主要特性比较,并给出了小信号条件下速调管的各种主要特性的简化分析方法.在这种简化分析方法中,把多腔速调管看作是几个双腔速调管的级联,并且没有考虑非线性、空间电荷效应和相对论效应等带来的影响,目的是阐述基本原理和基本分析方法.  相似文献   

19.
Deposition of granular materials into a container is a general industrial packing process. In this study, the deposition behaviour of dilute granular mixtures consisting of two types of particles that were of the same particle size but different particle densities in the presence of air was numerically analyzed using a coupled discrete element method (DEM) and computational fluid dynamics (CFD). Bilayer granular mixtures with light particles at bottom and heavy particles at top were first simulated. It was found that the presence of air significantly affected the flow behaviour of the bilayer mixtures. For the system with a relatively low initial void fraction, the air entrapped inside the container escaped through the dilated zones induced due to the friction between the powder bed and wall surfaces. The escaping air streams entrained light particles that were originally located at the bottom of the granular system. Consequently, these light particles were migrated to the top of the granular bed at the end of deposition process. More light particles were migrated when the deposition distance was increased. For the system with a high initial void fraction, some light particles penetrated into the top layer of heavy particles and created a mixing zone. Deposition of random mixtures with different initial void fractions was also investigated and the influence of initial void fraction on the segregation behaviour was explored as well. It was found that the increase of void fraction promoted segregation during the deposition in air. It was demonstrated that, for granular mixtures consisting of particles of different air sensitivities, the presence of air had a significant impact on the mixing and segregation behaviour during the deposition.  相似文献   

20.
Subjective logic provides a means to describe the trust relationship of the real world.However,existing fusion operations it offers treat fused opinions equally,which makes it impossible to deal with the weighted opinions effectively.A.Jφsang presents a solution,which combines the discounting operator and the fusion operator to produce the consensus to the problem.In this paper,we prove that this approach is unsuitable to deal with the weighted opinions because it increases the uncertainty of the consensus.To address the problem,we propose two novel fusion operators that are capable of fusing opinions according to the weight of opinion in a fair way,and one of the strengths of them is improving the trust expressiveness of subjective logic.Furthermore,we present the justification on their definitions with the mapping between the evidence space and the opinion space.Comparisons between existing operators and the ones we proposed show the effectiveness of our new fusion operations.  相似文献   

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