Effects of wall temperature on boundary layer stability over a blunt cone at Mach 7.99

Effects of wall temperature on stabilities of hypersonic boundary layer over a 7-degree half-cone-angle blunt cone are studied by using both direct numerical simulation (DNS) and linear stability theory (LST) analysis. Four isothermal wall cases with Tw/T0= 0.5, 0.7, 0.8 and 0.9, as well as an adiabatic wall case are considered. Results of both DNS and LST indicate that wall temperature has significant effects on the growth of disturbance waves. Cooling the surface accelerates unstable Mack II mode waves and decelerates the first mode (Tollmien–Schlichting mode) waves. LST results show that growth rate of the most unstable Mack II mode waves for the cases of cold wall Tw/T0=0.5 and 0.7 are about 45% and 25% larger than that for the adiabatic wall, respectively. Numerical results show that surface cooling modifies the profiles of rdut/dyn and temperature in the boundary layers, and thus changes the stability haracteristic of the boundary layers, and then effects on the growth of unstable waves. The results of DNS indicate that the disturbances with the frequency range from about 119.4 to 179.1 kHz, including the most unstable Mack modes, produce strong mode competition in the downstream region from about 11 to 100 nose radii. And adiabatic wall enhances the amplitudes of disturbance according to the results of DNS, although the LST indicates that the growth rate of the disturbance of cold wall is larger. That because the growth of the disturbance does not only depend on the development of the second unstable mode

Design and Implementation of Enterprise Human Resource Management System

人力资源管理是每一个企业单位都必须要进行的工作，提高人力资源管理的效率有助于提高企业单位竞争力。于是，开发一套企业内部使用的人力资源管理系统具有十分重要的实际意义。人力资源管理系统主要是对企业单位内部职工的人事档案、考勤情况、绩效考核、薪资情况和离职审批等操作进行管理和维护，以便于公司领导者根据本公司的发展战略对人力资源进行合理的分配，充分激发职工的内在潜能，能够实现个人更大的价值，与此同时，也给企业带来可观的经济效益和价值。此外，相比于传统的人工手动管理企业的各种资源和文档，该人力资源管理系统能够提高职工的工作效率、企业机密数据的安全性、也能够减少资源的浪费，节约成本。因此，人力资源管理系统...Human resources management must be carried out in each business unit, raising the efficiency of human resources management will help improve the competitiveness of enterprises. So, develop a set of human resource management system for the enterprise internal has very important practical significance. Human resource management system mainly to employees in enterprises, to Management and maintenance...学位：工程硕士院系专业：软件学院_工程硕士(软件工程)学号：X201223026

保单现金价值强制执行的反思与重构

通过对保单现金价值返还请求权执行说的反思,发现该学说关于保单现金价值返还请求权系附条件债权的观点存在问题,法院和债权人通过代位解除保险合同的执行方法,更是过度干预投保人与保险人之间的合同自由,同时损害被保险人和受益人的利益,且不符合强制执行法上的比例原则要求。保单现金价值具有多元的变现方式,应重新确立保单质押贷款权、投资账户价值部分提取权、分红请求权作为对保单现金价值强制执行的标的,并在此基础上对强制执行方法进行重构,以助于实现债权人、投保人、保险人、被保险人和受益人之间的利益平衡

《海商法》实施25年司法适用研究报告

《中华人民共和国海商法》(简称《海商法》)实施至今已有25年。对《海商法》进行全面修订,已成为业界共识,但仅从理论价值和制度规范层面进行研究,尚存不足。对自1992年11月7日《海商法》颁布以来至2017年12月31日为止中国裁判文书网收录的30 375篇海事海商纠纷案件裁判文书予以实证研究,就《海商法》实施以来的司法适用情况,特别是比较《中华人民共和国合同法》《中华人民共和国物权法》等一般性民商事法律在海事海商纠纷案件中的司法适用情况进行分析,揭示《海商法》在司法适用中出现的\"虚置化\"现象,探讨该现象背后的原因,为《海商法》修订提供司法依据。2018年国家社科基金项目“《海商法》修订中重大问题研究

“一带一路”背景下福建自由贸易港高端航运要素聚集的法律和政策保障机制构建论要

通过对世界各国(地区)自由贸易港产业结构与制度发展趋势的梳理总结,立足于外部环境与福建内部资源、能力、核心竞争力的全面分析,认为福建探索建设自由贸易港应当以航运保险、航运资产...2018年度国家社会科学基金项目“《海商法》修订中重大问题研究”(项目编号:18BFX208)阶段性研究成

关于奇异非线性两点边值问题的一点注记

在k（x）具有较强奇性的情况下证明了奇异非线性两点边值问题正解的存在性．同时提出了一个C1正解存在的充要条件

The performance of passive DMFC

研制了两只单体电池串联的被动式直接甲醇燃料电池(DMFC),无外部泵等辅助设施。考察了甲醇的浓度和温度、空气提供方式对单体电池性能的影响及单体电池的长期运行性能。单体电池在室温(25℃)下,贵金属载量为2.5 mg/cm2、甲醇浓度为3 mol/L时,性能最佳,峰值功率密度可达10 mW/cm2。提高甲醇温度和采用流动的空气,可提高电池的性能。单体电池在无水热管理系统1、00 mA放电的条件下,可在室温下连续、稳定地工作4 h。A passive direct methanol fuel cell(DMFC) with two single cells in series without auxiliary devices such as external pumps was designed and fabricated.The effects of methanol concentration and temperature,the air supply mode on the performance of single cell and the long-time operation performance of single cell were investigated.The single cell had optimal performance at room temperature(25 ℃) with 3 mol/L methanol and the noble metal loading was 2.5 mg/cm2,the peak power density could reach 10 mW/cm2.The increasing of methanol temperature and using flowing air could improve the performance of the cell.The single cell could work stably and continuously for 4 h at room temperature under the condition without water and thermal management systems and 100 mA discharge

分辨率优化的混合WENO格式

为提高有限差分格式的分辨率,利用傅里叶分析对WENO格式进行色散及耗散优化,并给出优化的线性权重.用优化后的WENO格式与保单调格式（MP）进行加权混合,得到新的加权混合WENO格式（H-WENO）.通过一维激波管问题、Shu-Osher问题及二维双Mach反射问题及R-T不稳定性问题对格式进行数值测试.结果显示,新格式具有强健的激波捕捉能力和对小尺度波结构的高分辨率,与原WENO格式相比改进明显

高血压病人围术期麻醉体会

目的探讨高血压病人围术期全身麻醉用药及有关处理方法。方法术前30min东莨菪碱和咪唑安定肌注;气管插管全麻诱导用咪唑安定、芬太尼、阿曲库铵、福尔利、艾司洛尔,静脉注射,结合表面麻醉完成气管内插管;术中做到充分通气、镇静和镇痛,严密观察血压,若ABP高者则用硝酸甘油降压;艾司洛尔应用于心动过速;术后PCA(自控镇痛)镇痛及适度镇静下拨管。结果本组术中利用硝酸甘油降压共34例,血压大部分较平稳;心动过速16例,艾司洛尔静脉治疗后正常;室性早搏者4例;l例房颤患者出现室颤、经积极心肺脑复苏而未出现并发症。术后17例ABP超过麻醉前4KPa,加强PCA镇静镇痛后能下降;窦性心动过速27例,艾司洛尔静脉治疗后心率下降至正常。本组均未发生脑血管意外,术后随访经治疗均出院。结论高血压病人采用全麻,合理用药及处理方法,可保障病人度过围手术期

Structure and electrochemical performance of Mg-doping nickel hydroxide

采用化学共沉淀法制备出不同含量Mg掺杂的氢氧化镍样品。应用X-射线衍射(XRD),傅里叶变换红外光谱(FTIR)和热重分析(TG)手段对样品的结构进行了表征,并用循环伏安法研究了样品的电化学性能。结果表明:与Mn、Al等元素掺杂到一定含量后使Ni(OH)2晶型由!型转化为"型不同,即使Mg掺杂含量达到30%,样品仍为#型。但样品晶格产生畸变,晶粒尺寸随Mg含量的增加先变小后增大,电化学性能随Mg含量的增加先变好后变坏。Mg最佳含量为5%左右,此时OH-数量增多,产生了大量的晶格畸变,c轴拉长,有利于质子扩散系数的变大,增强了反应的可逆性,提高了电极充电效率和活性物质的利用率,从而改善了电极的电化学性能。The different amount of Mg-doping Ni(OH)2 samples were prepared by a coprecipitation method. The crystal structures were characterized by XRD, FTIR and TG methods. The electrochemical performances were also investigated by cyclic voltammetry method. The results show that even the Mg-doping content reaches 30%, the sample still is β-phase, which is different from Mn-doping or Al-doping samples in which the samples are changed to α-phase from β-phase when the doping amount reaches some levels. The distortion of crystal lattices are happened. The size of crystalline grains diminishes and then increases, and the electrochemical performances also are better and then worse when the Mg-doping amounts increases. The suitable Mg-doping amount is about 5%. In this case, the number of OH-increases, the crystal lattice distortion is engendered, and the interlayer distance c is stretched, which are favorable to enhancement of the proton transfer between electrode materials. Therefore, the reversibility of electrode reaction is improved, the charge efficiency is increased and the utilization of active materials is promoted, which results in improvement of electrochemical performance