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41.
针对钢铁企业物流公司客户关系管理现状,及其客户服务请求处理流程中的不足,提出了基于呼叫中心的钢铁企业最优化客服请求处理流程及其技术实现,给出了平台功能设计,探讨了平台实现的关键技术。该系统充分满足客户满意度以及服务请求处理的及时性,快速性,确切性,可操作性等方面要求。  相似文献   
42.
为解决车辆在拥堵环境中因车速波动较大所带来的跟驰平稳性较差、跟踪无效或不安全等问题,提出了基于车辆模型和深度强化学习的多目标优化跟驰方案。首先基于车辆横纵向动力学建立车辆跟驰模型,然后根据车间距误差、速度误差、横向偏差及相对偏航角等,利用深度确定性策略梯度算法得到跟驰车的加速度和转向角,以更平稳安全地控制跟驰车辆。经NGSIM公开驾驶数据集进行测试与验证,该方案可有效地提升跟驰车辆的稳定、舒适与安全性,对保证交通安全和提升道路通行能力具有重要意义。  相似文献   
43.
为确定合理的界面间约束与接触关系,采用ABAQUS中3种不同的约束与接触关系基于现有试验试件进行模拟,将数值分析结果与试验结果与进行对比分析。研究表明:采用内聚力模型的有限元模型破坏形态与试验结果较为一致,绑定约束次之,而采用接触摩擦模型的有限元模拟结果与试验差别最大;以试验开裂荷载与极限荷载为分析对象,绑定约束与内聚力模型的数值分析结果与试验吻合较好,而接触摩擦模型的数值分析结果与试验差异较大;与绑定约束模型相比,内聚力模型能够较好地模拟试件界面的损伤。因此,当采用ABAQUS进行预制桥面板与UHPC湿接缝的界面受力的有限元分析时,宜采用内聚力模型或绑定约束模型,不宜采用接触摩擦模型。  相似文献   
44.
人水关系是人类与自然界关系中最重要的关系之一,也是人类一出现就始终存在且复杂程度不断加深的一类关系。在对人水关系分析总结的基础上,提出了人水关系学的概念和思考,论述了人水关系学的提出背景和重要意义;构建了人水关系学的学科体系框架,阐述了人水关系学的主要内容,包括人水关系学的理论基础、方法论、应用实践;在分析学科发展趋势的基础上,对人水关系学未来全面、系统的研究进行了展望,并从科学研究、学科建设、学术交流与国际合作3个方面对人水关系学的发展进行战略布局。为进一步研究人水关系、丰富人水关系学内容、发展人水关系学学科体系及制定学科发展战略提供参考。  相似文献   
45.
Simulation of smoke flow and longitudinal ventilation in tunnel fire   总被引:5,自引:0,他引:5  
1 Introduction The tunnel is one of the important facilities of railroad and highway transportation, and also a throat of railroad and highway. With the development of transportation, there are more and more tunnels. Although the tunnel fire occurs seldo…  相似文献   
46.
CH_4 storage associated with adsorbed natural gas(ANG) technology is an issue attracting great concern.Following the Advanced Research Project Agency-Energy(ARPA-E) targeted deliverable capacity of 315 cm~3·cm~(-3)(STP), hundreds of thousands of materials have been experimentally or theoretically evaluated,while the best results still show a 35% gap from the target. Moreover, recent theoretical research reveals that the target is beyond the possibility that real materials can be designed. To get rid of the awkward situation, we make attempts on investigating the CH_4 delivery performance under other operation conditions. Methods of raising the discharge temperature(to infinite high) or elevating the storage pressure(to 25 MPa) have been proved to show limited effectiveness. In this work, it is found that the ARPA-E target can be achieved by using a decreasing storage temperature strategy. By taking 280 Co RE(computation-ready, experimental) COFs(covalent organic frameworks) as ANG materials, when reduce the storage temperature to 190.6 K, the highest deliverable capacity can reach 392 cm~3·cm~(-3)(STP), and16.1% Co RE COFs can surpass the target. The target is also achievable when storage at 220 K. Structure performance relationships study shows strong correlation between deliverable capacity and void fraction. Hence, 120 hypothetical COFs are generated to ascertain the optimum void fraction. In addition,the performance of 2 D-COFs can be greatly enhanced by increasing the interlayer spacings, e.g. CH_4 deliverable capacity(storage at 190.6 K) of ATFG-COF can be improved from 239 to 411 cm~3·cm~(-3)(STP) when interlayer spacing is enlarged to 1.65 nm.  相似文献   
47.
Polo-like kinase 1 (PLK1) plays an important role in cell cycle progression and proliferation in cancer cells. PLK1 also contributes to anticancer drug resistance and is a valuable target in anticancer therapeutics. To identify additional effective PLK1 inhibitors, we performed QSAR studies of two series of known PLK1 inhibitors and proposed a new structure based on a hybridized 3D-QSAR model. Given the hybridized 3D-QSAR models, we designed and synthesized 4-benzyloxy-1-(2-arylaminopyridin-4-yl)-1H-pyrazole-3-carboxamides, and we inspected its inhibitory activities to identify novel PLK1 inhibitors with decent potency and selectivity.  相似文献   
48.
The true stress--strain curves of TC16 alloy with a wide range of strain rates were investigated under uniaxial quasi-static tension and uniaxial dynamic compression with the lnstron 8032 test machine and the split Hopkinson bar respectively. The results indicate that the true stress increases with increasing strain rate, while decreases with increasing temperature. Under the 105 s^-1 high strain rate and temperature higher than 673 K, the true stress would even be less than that under quasi-static condition. A new method incorporating TCl6's stress strain curve developing item was proposed to determine the coefficients in J-C model easily and to avoid the estimation of the adiabatic temperature rising. The Johnson-Cook dynamic constitutive relationship for TC16 was obtained for the first time. Good agreement was obtained between the model prediction and the experimental stress--strain curves for TC16 under both quasi-static and dynamic loadings.  相似文献   
49.
This paper investigates the interfacial structure in hot-wall CVD TiN/κ-Al2O3 multilayer coatings using both HREM and DFT modeling. Two multilayers with different thicknesses of the TiN layers (50 and 600 nm) separating the κ-Al2O3 layers are analyzed. The general microstructure of the two multilayers is relatively similar. The TiN layer in the thicker TiN/κ-Al2O3 coating is thick enough to be several TiN grains high. This means that epitaxial columns, which are often found in the thinner TiN/κ-Al2O3 coatings, are not present. However, the orientation relationships at the TiN/κ-Al2O3 interfaces are the same in both multilayers. The HREM investigations show that κ-Al2O3 (001) planes can grow directly on flat (111) TiN faces, without any other phases or detectable amounts of impurities, such as sulphur, present. Where the TiN layers are more curved, γ-Al2O3 can be grown, at least partly stabilized by the cube-on-cube orientation relationship between γ-Al2O3 and the underlying TiN. The DFT calculations show very similar adsorption strengths for an O monolayer positioned on Ti-terminated TiC(111) and TiN(111) surfaces, with preferred adsorption in the fcc site. O adsorption on N-terminated TiN(111) is much weaker, with preferred adsorption in the top site. Calculated elastic-energy contributions yield a higher stability for κ-Al2O3 on TiN(111) than on TiC(111) and a higher stability for κ-Al2O3 than for α-Al2O3 on both TiC and TiN. This indicates that the observed higher stability of κ-Al2O3 on TiC(111) than on TiN(111) is not due to the lattice mismatch, while the preferred epitaxial growth of κ-Al2O3 over α-Al2O3 can be partly attributed to the mismatch.  相似文献   
50.
The technology of cold pressure welding was adopted to achieve the bonding of Al/Cu(limited soluble and forming compounds),Ag/Ni(hardly mutual soluble),and the relative state of interface was tested by HREM.The results indicate that stable interface is always corresponding to the low interfacial energy value;the stable interface is not coherent but partly-coherent because of the twisting of grain boundary caused by pressure,meanwhile existing dislocation.Namely,the interfacial match and other states under the condition of cold pressure welding are different from the situation that under the condition of thermal action.Moreover,theoretical analyses and calculation on the base of thermodynamics,crystallogeny ,solid physics etc,were discussed.  相似文献   
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