基于收益管理和仿真的第三方仓储资源分配

针对不确定市场需求条件下第三方仓储资源的能力规划与分配问题,构建随机数学规划模型,理论分析证明了最优资源分配量的存在性,并指出最优资源分配量是单位资源成本的递减函数、单位资源收益和单位损失成本的递增函数。鉴于解析求解的复杂性,基于收益管理思想,结合离散事件仿真技术和响应曲面法,提出一种新的分析求解框架:收益管理用于细分顾客、构建资源分配策略,仿真模型刻画系统随机特性并评估系统绩效指标,响应曲面法则优化分配策略并探寻绩效改进方向。案例研究和仿真实验结果显示,根据顾客类别分配仓储能力的策略优于传统的先到先服务策略,收益管理、响应曲面法与仿真的综合集成,能够提高系统收益,从而使本文所提方法体系得到了有效验证。     

液相-固相还原法克服团聚制备高性能超级电容器用石墨烯电极材料

以水合肼为还原剂采用液相预还原-冷冻干燥-固相充分还原的方法制备的石墨烯电极材料具有十分优越的电化学性能,在超级电容器中比电容值达到336F·g-1(10 mV·s-1,循环伏安法),较液相还原石墨烯(270F·g-1)提高24%,同时亦优于固相还原石墨烯(323 F·g-1).对液相预还原氧化石墨烯采取冷冻干燥,既避免了液相直接还原干燥过程中的团聚现象,同时也有效地增加了固相还原石墨烯的无序度,从而进一步提高了石墨烯的电化学性能.     

金刚石切削Soda-lime玻璃中的刀具磨损及其对工件表面粗糙度的影响

金刚石切削加工光学玻璃时,工件表面粗糙度与刀具磨损直接相关,为研究切削距离递增下的金刚石刀具磨损及其对工件加工表面粗糙度的影响,进行了Soda-lime玻璃金刚石切削的刀具磨损试验,并对刀具磨损形貌、后刀面磨损带的材料成份、工件的表面形貌及粗糙度进行了检测.结果表明:切削距离递增下的金刚石刀具前刀面磨损表现为平滑且均匀的月牙洼磨损,后刀面磨损表现为磨损带逐渐增大,且磨损带内有沿切削方向的微沟槽产生;切削距离未达到150 m时,工件表面粗糙度Rq、Ra及Rmax值始终低于32、25及300 nm,切削距离超过150 m后,工件表面粗糙度显著增大.机械摩擦作用、热化学作用及磨料磨损作用为导致金刚石刀具磨损的主要原因.     

不同波长激光同时辐照薄膜热效应研究

通过分析两个不同波长激光同时辐照下薄膜体内驻波场分布并求解热传导方程,得到1 064 nm激光和355 nm激光在三倍频分离膜内共同作用下二维温度场分布.研究表明：1 064 nm激光和355 nm激光共同作用引起薄膜体内的温升峰值高于相同能量1 064 nm激光单独作用引起的薄膜体内的温升峰值,低于相同能量355 nm激光单独作用引起的薄膜体内的温升峰值.     

四种不同形状微粒的摩擦学性能研究

为了减少润滑液对石油的依赖,发展环境友好水基润滑液,本文通过在蒸馏水中加入螺旋藻、白葡萄球菌、寡核苷酸和丝素四种水溶性微粒来改善水的摩擦学特性.采用原子力显微镜和扫描电子显微镜对螺旋藻、白葡萄球菌、寡核苷酸和丝素进行结构表征;采用微摩擦试验仪对蒸馏水和四种水基润滑液摩擦性能进行了评价,采用流变仪对其流变性进行了评价.结果表明:①螺旋藻结构为螺旋状,白葡萄球菌为球状,寡核苷酸和丝素为线状;②螺旋藻的减摩效果最好,白葡萄球菌次之,最后是寡核苷酸和丝素;随着载荷增大蒸馏水摩擦系数减小,四种水基润滑液摩擦系数均增大;随着滑动速度增大摩擦系数均减小;③蒸馏水中添加微粒后仍为牛顿流体,但黏度增大.通过对机理进行分析,认为螺旋藻减摩效果最好是由于表面的螺旋结构能够产生足够大的滑动摩擦力,容易克服滚动阻力偶使微粒滚动起来;载荷增大四种水基润滑液摩擦系数均增大是微粒滚动阻力偶增大造成的;滑动速度增大四种水基润滑液摩擦系数均减小是微粒聚集体逐渐被分解造成的.     

Laser Resistance of Ta2O5/SiO2 and ZrO2/SiO2 Optical Coatings under 2 9m Femtosecond Pulsed Irradiation

Ta2O5/SiO2 and ZrO2/SiO2 high reflecting （HR） coatings are prepared by ion beam sputtering and electron beam evaporation, respectively. The laser-induced damage thresholds （LIDTs） of these samples are investigated with 2μm femtosecond pulse lasers （80fs, 1kHz）. It is found that the Ta2O5/SiO2 HR coating has a higher capability of laser damage resistance than the ZrO2/SiO2 HR coating in the 2μm femtosecond regime. The scanning electron microscope results show that the damage sites of the ZrO2//SiO2 FIR coating have a relatively porous structure, the loose structure of coatings will provide more sites for water molecules, and the LIDTs of HR coatings will be reduced as a result of the strong water absorption at the wavelength of 2 μm.     

基于偏振测量的雾天图像场景分割

现有场景分割方法主要依赖于图像亮度、颜色和纹理等特征,然而在雾天图像中提取这些特征将变得困难且不稳定.基于此本文提出了适用于雾天图像场景分割的特征矢量,以及相应的特征提取算法.特征矢量由目标偏振度、深度和颜色三部分组成.特征提取算法分别为:用去相关的方法从图像偏振度分离出大气偏振度和目标偏振度；根据雾天退化模型和雾天图...     

高效液相色谱-荧光/紫外串联测定鱼体中硝基苯同系物

采用高效液相色谱-荧光/紫外检测器串联测定鱼体中7种硝基苯同系物。通过色谱柱、荧光激发和发射波长等条件的优化,实现7种硝基苯同系物组分的完全分离,并通过荧光-紫外串联检测提高了定性的准确度。结果表明:7种硝基苯的峰面积与其质量浓度在0.1～2.0μg/mL范围内呈线性关系,相关系数均大于0.999;检出限为6.3～151.0ng/g;方法的回收率为71.48%～90.14%;相对标准偏差在4.38%～13.29%范围。     

Characterizations of Stress and Strain Variation in Three-Dimensional Forming of Laser Micro-Manufacturing

A micro-manufacturing technology is presented to form three-dimensional metallic micro-structures directly. Micro grid array structures are replicated on a metallic foil surface, with high spatial resolution in micron levels. The numerical simulation results indicate that the material deformation process is characterized by an ultrahigh strain rate. With increasing pulse duration, the sample absorption strain energy increases, and the sample deformation degree enlarges. The stress state of the central point fluctuates between tensile stress and compression stress. The stress state of the angular point is altered from compressive stress to tensile stress due to geometry and loading conditions. The duration length of pulse stress has an effect on the stress state, as with the increase of pulse duration, fluctuation in the stress state decreases. Therefore, laser micro-manufacturing technology will be a potential laser micro forming method which is characterized by low cost and high efficiency.     

Study on Electric Double Layer of a Cylindrical Particle with Functional Theoretical Approach

A new method, i.e. the iterative method in functional theory, was introduced to solve analytically the nonlinear Poisson-Boltzmann （PB） equation under general potential ψ condition for the electric double layer of a charged cylindrical colloid particle in a symmetrical electrolyte solution. The iterative solutions of ψ are expressed as functions of the distance from the axis of the particle with solution parameters： the concentration of ions c, the aggregation number of ions in a unit length m, the dielectric constant e, the system temperature T and so on. The relative errors show that generally only the first and the second iterative solutions can give accuracy higher than 97%. From the second iterative solution the radius and the surface potential of a cylinder have been defined and the corresponding values have been estimated with the solution parameters, Furthermore, the charge density, the activity coefficient of ions and the osmotic coefficient of solvent were also discussed,