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1.
根据压缩传感理论和关联成像模型,将压缩传感理论应用于关联成像中,实现了传统的双臂关联成像的压缩传感重构。通过仿真实验验证了压缩传感用于关联成像的可行性,以峰值信噪比(PSNR)为衡量指标,分别对压缩传感和传统关联算法的重构图像质量进行了量化。仿真实验表明,压缩传感和关联算法的重构效果均随测量次数的增加而变优,在相同的测量次数下,压缩传感在关联成像中的重构图像的PSNR比传统的关联重构图像高20 dB以上。将压缩传感用于实际双臂关联成像的实验结果表明,压缩传感可以实现双臂关联成像装置的图像重构,但其重构质量很难优于传统关联算法的重构。针对这一实际实验与仿真实验似乎相矛盾的特殊现象,从双臂对称性的角度进行了合理解释,并利用实验中实际的散斑场对该现象进行了验证,最后提出了解决方案。 相似文献
2.
通过在自主研制的热冲压实验线上开展汽车纵梁热冲压实验,探明并对比了无涂层和不同润滑条件下Al-Si涂层22MnB5板对复杂零件热冲压成形质量和组织性能的影响。结果表明:①相比于无涂层板,涂层板能有效改善氧化脱碳现象,但涂层中形成的孔隙和裂纹容易导致零件在成形时产生破裂;采用水基石墨润滑不能消除破裂;采用玻璃润滑能有效避免破裂。②无涂层板的抗拉强度和屈服强度较高,无润滑和石墨润滑涂层板次之,玻璃润滑涂层板的抗拉强度和屈服强度较低;无涂层板的延伸率较涂层板的延伸率大。③玻璃润滑涂层板的表面粗糙度较小,无涂层板次之,无润滑和石墨润滑涂层板的表面粗糙度较大。 相似文献
3.
The composite spectrum (CS) data fusion technique has been shown to simplify rotating machines faults diagnosis by earlier studies. Faults diagnosis with the earlier CS relied solely on the amplitudes of several harmonics of the machine speed, owing to the loss of phase information leading to its computation. The proposed improved CS applies the concept of cross power spectrum density for computing a poly-Coherent Composite Spectrum (pCCS) of a machine, which retains amplitude and phase information at all measurement locations. The present study compares the proposed pCCS method with the earlier CS method for faults diagnosis in rotating machines, using experimental data from a rotating rig. Results and observations show that the proposed pCCS offered a much better representation of the machines dynamics when compared to the earlier CS method and hence better fault diagnosis. 相似文献
4.
邻氯苯亚甲基丙二腈(CS)作为催泪剂在各国反恐防暴装备中得到了广泛应用。实际使用时,燃烧和爆炸驱动分散CS形成气溶胶的同时会导致其分解。为提高CS的利用效率,有必要研究其热稳定性和热分解性能。本工作应用热重分析与差示扫描量热法(TGA/DSC)研究CS在不同升温速率时产生的热失重和热效应现象,并与傅里叶变换红外光谱法(FTIR)联用对逸出气体进行分析;用热裂解与气相色谱-质谱(PY-GC/MS)技术研究CS在350~650 ℃的热分解性能。实验发现:CS在96 ℃附近熔融;310 ℃附近沸腾;450~550 ℃之间发生首次热分解,热分解产物与温度有着密切关系,550 ℃的分解产物有4 种;650 ℃的热分解程度加深,分解产物多达 10 种。因此,建议CS与烟火剂混合使用时,烟火剂的燃烧温度以不超过450 ℃为宜。 相似文献
5.
Carbon steel (CS) is the most common material used in oil production. Based on surface wetting state, the corrosive wear behavior of CS in oil-water fluid was investigated. The surface wetting state of the metal in oil-water fluids with different water cut and flow velocity was measured using a specially constructed device. Wear loss, corrosion loss, and corrosive wear loss of the CS samples in different oil-water fluids were measured by a reciprocating corrosive wear tester. The damage morphology of the CS samples was observed using scanning electron microscopy (SEM) and the element distribution on the surface was detected by energy-dispersive X-ray spectroscopy (EDS). The results indicated that the surface water wetting rate of the metal increased with water cut and decreased with flow velocity in the oil-water fluid. Wear, corrosion, and corrosive wear behavior of the CS was related to the surface wetting film and surface reaction film. In this test range, the synergetic action is negative and chlorine embrittlement occurs in the fluid with high water cut and low velocity. The damage mechanism of the CS was abrasive wear with selective corrosion. 相似文献
6.
催泪喷射剂是常用控暴装备,尤其是警用催泪喷射器的主装药剂。当前催泪喷射剂中的刺激剂组分一般为西埃斯(CS)和合成辣椒素(OC),本文研究了催泪喷射剂中的刺激组分西埃斯(CS)和合成辣椒素(OC)的分析方法,建立了采用毛细管气相色谱柱分离,FID检测器进行检测的技术途径。对色谱条件进行了优化,色谱柱:HP—5;载气:高纯氮气(1.5mL/min);进样口温度:250℃;检测器温度:280℃;程序升温:初始温度80℃,保持0.5min后以20℃/min的速率升至250℃保持5min。方法的相对标准偏差为0.35%(CS)和0.47%(OC),最低检出浓度为0.05μg./mL(CS)和0.1μg/mL(OC),方法的平均回收率98%(CS)和101%(OC),两者分别在1.0~100.0μg/mL(CS)和5~1000μg/mL(OC)范围内有良好的线形关系。 相似文献
7.
In this research, a new optimization algorithm, called the cuckoo search algorithm (CS) algorithm, is introduced for solving manufacturing optimization problems. This research is the first application of the CS to the optimization of machining parameters in the literature. In order to demonstrate the effectiveness of the CS, a milling optimization problem was solved and the results were compared with those obtained using other well-known optimization techniques like, ant colony algorithm, immune algorithm, hybrid immune algorithm, hybrid particle swarm algorithm, genetic algorithm, feasible direction method, and handbook recommendation. The results demonstrate that the CS is a very effective and robust approach for the optimization of machining optimization problems. 相似文献
8.
A problem of optimal assignment of parallel program branches to processor cores of a distributed computer system (CS) in order to minimize its execution times is formulated. The formulation takes into account the hierarchic organization of the distributed CS communication network, the property of multicore processors, and the structure of a parallel program information graph. Stochastic sequential and parallel algorithms for solving the problem are proposed. Results of algorithm modeling by a cluster CS are presented. 相似文献
9.
腐蚀损伤会加速疲劳载荷下的飞机铝合金结构裂纹的萌生和扩展,威胁结构安全性。针对腐蚀影响下的疲劳裂纹扩展的随机性本质,对预腐蚀LD10CS合金的预腐蚀疲劳试验进行了数据分析,提出了基于可靠性的腐蚀裂纹扩展速率表征方法,与试验结果对比表明,该方法可以给出LD10CS腐蚀疲劳裂纹扩展速率的上下限,进而给出该种材料铝合金构件的疲劳裂纹扩展寿命的上下限,为评估铝合金构件的寿命提供了依据。 相似文献
10.
CS5463是美国Cirrus Logic公司新近推出的单相双向功率/电能计量集成电路芯片.介绍了CS5463的工作原理、应用特点、主要功能及典型应用.由于很多功能都在单芯片内实现,采用CS5463设计电能测量仪表可以提高电路的稳定性,也有利于简化设计,缩短开发,降低成本. 相似文献
11.
在介绍新型开放型集散控制系统CS1000/CS3000的基础上,文章重点对工程的概念和系统测试功能的特点、类型、功能及应用进行了阐述。 相似文献
12.
针对传统的贝叶斯网络(Bayesian network, BN)结构学习算法运行效率低、算法易早熟、学习效果不理想等缺点,选取布谷鸟(Cuckoo search, CS)和粒子群(Particle swarm optimization, PSO)智能算法,结合BN结构特点,提出了一种CS-PSO的BN结构学习算法。首先,对CS算法从以下三个方面进行改进:利用最大支撑树来指导CS算法的初始化方向,利用解的适应度来调节解的寻优及舍弃过程,利用PSO算法来进行CS算法的位置更新。其次根据BN的结构特征,将CS-PSO算法应用于BN的结构学习。最后采用chest clinic、 credit和car diagnosis三种经典网络作为仿真模型,进行贪婪算法、 K2算法、 CS算法和CS-PSO算法的建模和仿真比较。结果表明, CS-PSO算法在BN的结构学习中,收敛速度快、收敛精度高且稳定性好,可以更快、更优地得到精确的贝叶斯网络结构模型。 相似文献
13.
Pentraxin-3 (PTX3), the prototype of long pentraxins, seems to influence complement system (CS) modulation.
PTX3 and CS sustain carcinogenesis, enriching tumor microenvironment (TME) with pro-inflammatory molecules
promoting angiogenesis in prostate cancer (PC) and renal cell carcinoma (RCC). Furthermore, cancer cells
overexpress complement regulatory proteins, such as CD46, CD55 and CD59, which negatively affect complement
pathways for support cancer cells survival. This viewpoint aims to elucidate the ambivalent role of PTX3 and the CS
in the context of tumor microenvironment (TME). 相似文献
14.
Here we propose a generalized procedure for a two-parameter assessment of the Combustion stability (CS) of industrial gas turbines. In evaluating the CS, this procedure employs two parameters of measured dynamic pressure data: the Root-mean-square (RMS) pressure as the primary parameter and the damping ratio as a secondary parameter. The former tells the time-averaged level of the dynamic pressure, and, the latter, the degree of acoustic energy loss. A data point pairing the two parameters, which are evaluated at a specific instance of a combustion process, identifies Instantaneous combustion stability (ICS) by its location on a 2-D domain of both parameters. Collective representation of the ICS points on the domain produces a CS map of the combustion process. The locus of the ICS point on the map represents the temporal variation of CS during the combustion process. The biparametric assessment procedure divides the CS map into three regimes (i.e., stable, transitional and unstable) by utilizing two threshold values for the RMS pressure and one for the damping ratio. The feasibility of the proposed procedure was tested with the dynamic pressure data from a model gas turbine combustor burning synthetic natural gas. Then the technique was applied experimental data obtained from a laboratory-scale lean premixed combustor to identify the three regimes of the combustion process of a reported case. We found that the procedure is able to provide gas turbine operators with valuable information on CS during a combustion process, especially on the transitional regime. 相似文献
15.
本文介绍了几种基于CENTUM CS1000/CS3000的实时数据采集方法,包括OPC的存取规范,客户端开发环境和开发组件的安装和使用。重点介绍了如何通过OPC接口来存取实时数据。 相似文献
16.
The aim of this study is to investigate the lubrication of hyaluronic acid (HA) and chondroitin sulfate (CS) on the condylar cartilage of the temporomandibular joint. The wear behaviour of bovine condyle cartilage was explored against a zirconia ball with different lubrications under torsional fretting mode. The worn cartilage morphologies were observed using scanning electron microscopy and hemotoxylin and eosin staining. The results indicated that HA or CS could significantly lower the friction torque and dissipated energy of fretting interface and reduce the damage of the articular cartilage surface compared to the control (phosphate‐buffered saline). The mixture (HA and CS) could provide better protection for the cartilage layer. Absence of good lubrication in overloading torsional fretting process caused excessive cartilage wear. High concentration and high molecular weight HA or CS acted as good boundary lubricants, and the lubrication effect of their mixture was better due to their synergistic function. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
17.
This article addresses the problem of contact-state (CS) monitoring for peg-in-hole force-controlled robotic assembly tasks. In order to perform such a monitoring target, the wrench (Cartesian forces and torques) and pose (Cartesian position and orientation) signals of the manipulated object are firstly captured for different CS’s of the object (peg) with respect to the environment including the hole. The captured signals are employed in building a model (a recognizer) for each CS, and in the framework of pattern classification, the CS monitoring would be addressed. It will be shown that the captured signals are nonstationary, i.e., they have non-normal distribution that would result in performance degradation if using the available monitoring approaches. In this article, the concept of the Gaussian mixtures models (GMM) is used in building the likelihood of each signal and the expectation maximization (EM) algorithm is employed in finding the GMM parameters. The use of the GMM would accommodate the signals nonstationary behavior and the EM algorithm would guarantee the estimation of the optimal parameters set of the GMM for each signal, and hence the modeling accuracy would be significantly enhanced. In order to see the performance of the suggested CS monitoring scheme, we installed a test stand that is composed of a KUKA lightweight robot (LWR) doing peg-in-hole tasks. Two experiments are considered; in the first experiment, we use the EM-GMM in monitoring a typical peg-in-hole robotic assembly process, and in the second experiment, we consider the robotic assembly of camshaft caps assembly of an automotive powertrain and use the EM-GMM in monitoring its CS’s. For both experiments, the excellent monitoring performance will be shown. Furthermore, we compare the performance of the EM-GMM with that obtained when using available CS monitoring approaches. Classification success rate (CSR) and computational time will be considered as comparison indices, and the EM-GMM will be shown to have a superior CSR performance with reduced a computational time. 相似文献
18.
将质量功能展开的分析方法引入顾客满意度优化研究中,通过质量屋中矩阵图表的形式描述了顾客满意需求与企业资源配置要素之间的关联关系,并对此进行量化分析.通过定义资源配置要素配置率的概念,来解决顾客满意度和资源配置多因素间由于量纲不同导致组合优化困难的问题,建立了基于质量功能展开的顾客满意度优化决策模型.通过算例分析,说明了所建模型的有效性和合理性,解决了企业资源配置过程中实施顾客满意战略的多因素多目标的规划问题,实现了企业资源配置成本与顾客满意度的双赢目标. 相似文献
19.
对由泡沫金属铝芯和金属面板组成的三层和多层复合板四点弯曲条件下的变形和断裂行为进行原位观察。研究结果表明:在弯曲条件下,复合板有两种基本的破坏方式,一种是复合板表面凹陷(Indentation, ID),它是表面局部集中塑性变形的结果;另一种是泡沫铝内芯切断 (Core shear, CS),它是内芯在最大切应力作用下的破坏。对一个给定的三层复合板,当凹陷破坏的载荷极限FID大于内芯切断的载荷极限FCS时发生内芯切断式破坏,反之发生表面凹陷式破坏。对于多层复合板,破坏方式受金属面板制约,不能直接应用三层板的破坏判据。若三层板发生凹陷型破坏,具有与三层板相同金属面板厚度的多层复合板发生凹陷加内芯切断的混合型破坏。当三层板只发生内芯切断型破坏时,具有与三层板相同金属面板厚度的多层复合板完全发生内芯切断型破坏。 相似文献
20.
集散控制系统CS3000是新一代开放型、网络型集散控制系统,其显著特点是具有系统测试功能.本文从三种类型的工程概念和系统测试功能出发,介绍了集散控制系统CS3000在离子膜电解槽中的应用,使离子膜生产实现连锁控制. 相似文献
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