一种基于智能优化的摄像机标定方法研究

针对现有包装设备上对摄像机标定中传统优化算法存在的缺点,如对初始值敏感、收敛性差、易陷入局部最优解等,研究了量子粒子群优化算法在摄像机标定中的应用,提出了一种基于智能优化的摄像机标定方法,并给出了具体的步骤。实验结果表明该标定方法可以克服传统算法的不足,具有较高的精度,可以满足计算机视觉在包装工程中的应用。     

基于DMAIC理论的温湿度计检定流程优化方法研究

DMAIC理论通过定义、测量、分析、改进、控制五个阶段,实现对业务流程质量的改进与优化.本文以笔者所在单位温湿度计检定效率为切入点,以实验工作间检定流程为研究对象,利用DMAIC理论进行改进与优化,重点分析检定过程中的时序问题,尽可能减少无增值活动.同时,通过应用DMAIC理论提高了温湿度计检定的工作效率,亦有助于推动各专业岗位计量保障手段的革新.     

求解复杂优化问题的双层多种群粒子群优化算法

为解决粒子群优化算法存在的易早熟和精度低问题,提出了一种双层多种群粒子群优化算法.此算法采用上下两层,即下层N个基础种群和上层一个精英种群.各个基础种群相互独立进化,并从精英种群中得到优良信息指导自己的进化.上层精英种群首先通过接受各基础种群的当前最优粒子来更新自己的粒子集合,然后执行自适应变异操作,最后随机地向每一个基础种群输送出本次进化后的一个最优粒子来改进其下一轮搜索.该算法的并行双进化机制增加了群体的随机性和多样性,提高了全局搜索能力和收敛精度.实例仿真表明该算法具有较好的性能,尤其对于复杂多峰函数优化,成功率显著提高.     

基于量子粒子群优化的Volterra核辨识算法研究

将量子粒子群优化（QPSO）引入到非线性Volterra系统辨识中,提出了一种基于量子粒子群优化（QPSO）的Volterra级数辨识方法,利用QPSO算法估计出了非线性系统的Volterra核函数。提出的方法同时和传统的最小二乘法(LMS)辨识方法进行比较,仿真结果验表明,在无噪声干扰下,提出的方法与LMS方法都具有很好的辨识精度和收敛性。然而,在有噪声干扰下,无论在辨识精度、收敛性和抗干扰性方面,本文方法都优于传统的LMS方法,而且,随着噪声的增强,这种优势越明显。     

基于遗传算法的测试性优化分配方法

测试性分配是测试性设计中的一项重要环节.测试性分配参数主要是故障检测率(FDR)和故障隔离率(FIR).常用的权值分配法存在权值计算繁杂、分配结果需要调整等不足.优化分配是一种较好分配方法,它是在一系列的约束条件下,使分配的结果费效比最优.但是解决约束优化分配问题的内点法、最小乘子法等算法存在易陷入局部最优、寻找初始点...     

基于智能混合策略的测试集优化

利用基于粒子群和蚁群算法的智能混合优化策略,删除冗余测试向量以解决测试集的优化问题. 利用蚁群算法的并行搜索能力构造初始解集,通过粒子群优化算法将解集维数降低,确定每次迭代的个体最优解和全局最优解,并利用新粒子信息更新信息素,最终通过多次迭代找到一个或多个最优测试集. 通过多组数据实例分析可知: 该智能混合优化策略与蚁群算法等其他测试集优化算法相比,可得到多个可行性最优测试集;与蚁群算法相比可提高收敛速度,并降低蚁群算法参数选取对收敛结果的影响,从而避免次优解的出现.     

机器人精密减速器单工位测试流程优化方法

为提高精密减速器性能测试效率,提出一种单工位测试流程优化方法。基于测试项目序列描述定义,构建测试流程网络,将流程转化为起点与终点固定的最短路径的旅行商问题(travelling salesman problem, TSP)模型进行优化求解,通过最优解改进找到最优测试路径。该方法能够通过测试项目的序列描述,发掘出不同项目之间优化合并空间,最优解改进克服一般TSP模型仅对相邻项目间优化的问题。应用结果表明,该方法对精密减速器动态测试项目进行优化,可以缩短16.17%测试时间。     

基于PMOPSO方法的H型铲齿凸轮优化设计

给出一种H型铲齿凸轮的标准设计方法,用于解决多升程H型铲齿凸轮的优化设计问题。针对传统铲齿凸轮存在的过渡点冲击问题,提出基于H型凸轮从动件运动规律的铲齿凸轮设计方案。以凸轮面积为设计目标函数,以从动件的偏置量和初始位移为设计变量,在凸轮一般设计准则的基础上,考虑理论廓线曲率范围和压力角分布的约束条件,建立H型铲齿凸轮的优化设计模型。多升程H型铲齿凸轮的优化设计问题具有约束条件多、非线性强和计算复杂度高的特点,将多项式变异算子和标准粒子群优化结合,提出多项式变异粒子群优化方法。以此优化方法为基础,通过构造罚函数处理设计约束,分别求解三升程和四升程的H型铲齿凸轮优化设计问题。计算结果表明,提出的标准设计方法可显著降低多升程H型铲齿凸轮的工作轮廓面积,使铲削机构更加紧凑。     

基于方法研究及仿真的汽车零部件流程优化

为促进工业工程(Industrial Engineering,IE)在我国制造业中的推广应用,减少生产过程中存在的浪费,应用IE中的方法研究对某一铸造企业进行改善优化,基于“ECRS”原则使产品加工流程、布置经路和人机作业更加合理,并通过witness软件对人机作业改善前后进行仿真模拟,验证了人机分析的正确性,充分挖掘了人机闲余能力,增强了人机的协调配合,降低了人工成本.研究表明,在低投资下,工业工程方法是提高制造业整体竞争力的有效途径.     

大型医药物流中心流程优化研究

为提高医药物流中心的运作效率，提出了面向大型医药物流中心的流程优化方法，该方法针对医药物流中心普遍存在的问题，以流程图为载体，依照诊断、分析、应用、反馈和改进的过程对医药物流中心物流流程做系统化的改造，使流程简明规范、信息化水平提高，从而使得流程效率和服务水平均得到提高，降低了物流费用。文中给出了流程优化的具体步骤。     

An upper bound on the weight-balanced testing procedure with multiple testers

This paper presents the performance of the Weight-Balanced Testing (WBT) algorithm with multiple testers. The WBT algorithm aims to minimize the expected number of (round of) tests and has been proposed for coding, memory storage, search and testing applications. It often provides reasonable results if used with a single tester. Yet, the performance of the WBT algorithm with multiple testers and particularly its upper bound have not been previously analyzed, despite the large body of literature that exists on the WBT algorithm, and the recent papers that suggest its use in various testing applications. Here we demonstrate that WBT algorithm with multiple testers is far from being the optimal search procedure. The main result of this paper is the generalization of the upper bound on the expected number of tests previously obtained for a single-tester WBT algorithm. For this purpose, we first draw an analogy between the WBT algorithm and alphabetic codes; both being represented by the same Q-ary search tree. The upper bound is then obtained on the expected path length of a Q-ary tree, which is constructed by the WBT algorithm. Applications to the field of testing and some numerical examples are presented for illustrative purposes.     

A seismic optimization procedure for reinforced concrete framed buildings based on eigenfrequency optimization

Several seismic optimization methods have been proposed to improve the performance of reinforced concrete framed (RCF) buildings; however, they have not been widely adopted among practising engineers because they require complex nonlinear models and are computationally expensive. This article presents a procedure to improve the seismic performance of RCF buildings based on eigenfrequency optimization, which is effective, simple to implement and efficient. The method is used to optimize a 10-storey regular building, and its effectiveness is demonstrated by nonlinear time history analyses, which show important reductions in storey drifts and lateral displacements compared to a non-optimized building. A second example for an irregular six-storey building demonstrates that the method provides benefits to a wide range of RCF structures and supports the applicability of the proposed method.     

Development of an accelerated abrasion test apparatus with a standardized testing procedure

Depending on the nature of the working environment, the abrasive wear of concrete floor slabs can range from scratching or scuffing to impact and local crushing. To assess abrasion resistance it is, therefore, necessary to have a versatile apparatus. This investigation describes the development of a basic apparatus with three modes of action and a standardized testing procedure, for assessing the abrasion resistance of concrete slabs in the industrial environment. It consisted of a rotating plate carrying a total load of 65 kg so that it was sufficiently portable for both laboratory and site testing. Three different types of abrasion head—(a) revolving pads, (b) rolling wheels, (c) dressing wheels—could be fixed to the plate so that the effects of different modes of wear could be assessed. The abrasion resistance is expressed in terms of the depth of the groove produced by 15 min of abrasion. A laboratory programme was undertaken to assess the apparatus and test method. The factors examined included the methods of assessing the abrasive wear, the duration of the test, the minimum number of tests to reliably assess the abrasion resistance, the relative performance of the three types of test head and the mechanism(s) by which each head abraded the concrete surface. Consequently a standardized procedure was developed which was found to be sensitive to variations in surface conditions. This has the additional advantages of simulating service conditions and of being repeatable, easy to follow and with the cost and time of testing not being excessive.     

A procedure for fatigue testing of shaft-sleeve glued connections

We describe a procedure for testing-shaft-sleeve glued connections using anaerobic materials for high-cycle fatigue, present a scheme of numerical analysis of stresses in glued connections, and propose a criterion of the limiting state of these connections attained in the course of fatigue tests under conditions of excitation of vibrations in the resonance mode.     

静电放电测试中相关的问题研究

通过分析两台带宽均为1GHz的数字示波器在对静电放电模拟器的静电放电脉冲的测试中得到的不同结果,分别从IEC61000-4-2标准的测试要求、试验方法及数字示波器的波形采集的原理出发,提出了要想准确测试静电放电脉冲波形除了考虑数字示波器带宽指标外,还必须考虑数字示波器的采样速率.     

Luus-Jaakola optimization procedure for phase-only sampled-fiber Bragg gratings

We describe a Luus-Jaakola (LJ) optimization algorithm approach for the design of wavelength division multiplexing (WDM) optical communication systems by using phase-only sampled-fiber Bragg gratings. The LJ method is used to optimize the phase grating as well as the number of segments which form the grating. The numerical example of WDM is studied. The method is easily applicable and shows promising results with low refractive index modulation.     

An efficient optimization procedure for designing a capacitated distribution network with price-sensitive demand

This paper considers a location-allocation problem in a supply-chain distribution network with capacitated distribution centers and customers with price-sensitive demands. The problem determines location, allocation and price decisions in order to maximize the total profit under two supply policies. Serving all of the customers is compulsory under the first policy, but is optional under the second. The problem is formulated as a mixed-integer linear program and solved by a Lagrangian relaxation algorithm under each policy. The numerical study indicates that the proposed algorithms are highly efficient and effective for solving large-sized instances of the problem.     

Towards a uniform precracking procedure for fracture toughness testing

The precracking requirements for fracture toughness testing of metallic materials are investigated in this study. In addition, some experiments were performed in the transition region to quantify the consequences of violating these requirements. It is found that the different standards are not consistent. For most of the requirements some rationale can be found. Some theoretical developments were performed to justify the use of a fixed maximum stress intensity factor. This limit is tightly related to the fracture mechanism and to the fracture process zone. From an experimental point of view, a relatively limited effect of precracking on the fracture toughness is found.     

Lipid composition optimization in spray congealing technique and testing with curcumin-loaded microparticles

Spray-congealing, a technique based on the fast solidification of sprayed molten lipids, is considered a novel strategy to encapsulate natural products. Among others, it is a safe, low cost, fast and reproducible technique, with rising interest for several applications (e.g. food applications). One of the key parameters for the application of this technique is the lipid solidification temperature, which can be modulated by optimizing the lipid composition. In this work, three lipid components (beeswax, carnauba wax, and medium-chain triglycerides (Miglyol 812)) were selected, and the mixture composition modelled using a simplex-centroid experimental design. Three different lipid compositions were chosen to validate the proposed model, then tested in the preparation of curcumin-loaded microparticles (1.5%, w/w). The produced microparticles were analysed in terms of colour, morphology, particle size, encapsulation efficiency and load, physicochemical, crystalline, and thermal properties. Results evidenced that microparticle’s properties, including encapsulation efficiency, vary according to the used lipid mixture, supporting their tailoring role. This fact brings advantages in the design of microencapsulation systems based on spray congealing processes, broadening their applicability. Moreover, lipid composition optimisation was proved to be an important tool to precede the development of spray-congealing applications.     

Effect of metal purity and testing procedure on surface tension measurements of liquid tin

The surface tension of liquid tin of three different grades of purity (99.85, 99.96, and 99.999%) was measured by the classical sessile drop method over the temperature range 523–1023 K, in heating and cooling regimes. The results obtained show that the metal purity affects the values of surface tension and its temperature dependence. The highest values of surface tension and smooth linear temperature dependence were obtained in cooling regime for tin of the highest purity. With increasing content of impurities, both surface tension and its temperature coefficient decrease while the scatter of the data increases. The surface tension values measured on heating regime show higher scatter, compared to those obtained in cooling regime, and the temperature dependence of the surface tension is curvilinear rather than linear.