果蔬气调库设计时需考虑的几个问题

气调库与一般高温库设计要求不同,本文就建库型式的选择、平面布置、库房的气密性、气凋库的安全,以及气调库制冷系统方案的选择、气调设备的选型等进行了详细的讨论.     

高温库改造成为气调冷库的实例探讨

本文介绍了厦门某食品公司的高温冷藏库改造成气调库的工艺设计实例。对高温库改造成气调冷库和直接建造气调库的异同进行分析比较。在对该具体实例进行设计调研和费用计算基础上，对一般高温库改造为气调库的典型问题，包括库房结构，制冷设备、气调系统选择和气调方式确定等进行了分析探讨。提出了高温库改造为气调库时注意的问题，对于非大宗短期贮藏、多品种、多批量的情况，柔性气调库方式的经济效益尤其明显，建议推广应用。     

大连市机电研究设计院小型气调库受青睐

气调库是目前被国内外公认的最先进的贮藏设施 ,大连市机电研究设计院自 1 984年已在全国各地建造了各种结构和形式的气调库几十座 ,建造气调库也由原先需进口库体材料、部分设备到现在全部国产化。然而过去研究设计院建造的气调库吨位一般均在 50 0 t以上 ,普通用户难以承受。为此该院瞄准市场 ,开发出农家经济型气调库。采用膜制氮机、二氧化碳脱除机和新型气密涂料 ,从而降低了农家经济型气调库的价格 ,一户或几户农民便能联合承受了。该院已为大连金州果树推广中心设计承建了国内首座 30 t小型气调库 ,各项指标均处于国内先进水平 ,受到…     

组合式气调库围护结构设计研究与分析

组合式气调库是一种新型的气调库,它的围护结构是其发挥气调贮藏功能的重要保障。从理论计算和实际测试两方面来深入分析了组合式气调库围护结构设计。     

果蔬气调冷库的气密层施工

近年来,果蔬气调冷库在国内有较快的发展,气调库与普通冷藏库的主要区别在于有气密层的施工.本文结合设计所承建的几个气调库项目,分别介绍了土建气调库、装配式气调库气密层的施工经验.     

装配式气调库的结构设计

本文介绍了装配式气调库的特点和围护结构的设计要点，工程实例的气密性测试结果，达到或超过西方发达国家常用的气调库气密性标准。     

气调库设计中制氮机的选用与计算

本文给出了一个适用于气调库中制氮机选用的数学模型，采用数学计算的方法取得了以往凭经验或参考同类气调库对制氮机进行选择的方法，该数学模型在实际应用中取得了令人满意的结果。     

浅谈我国气调库建设的现状和建设时应注意的几个问题

本文论述了我国果品气调库建设的发展历史和现状,并就新时期果品气调库的建设应注意的有关问题,发表了个人看法.     

我国气调库建设的现状及建设气调库时应注意的几个问题

本文论述了我国果品气调库建设的发展历史和现状,并就新时期果品气调库的建设应注意的有关问题,发表了个人看法.     

果蔬气调库贮藏中温湿度控制及气密性措施

近几年果蔬气调库发展迅速。气调库与一般高温库温度、湿度控制要求不同 ,温湿度控制不但关系到贮藏食品的品质 ,还会影响到气调库中设定的气体成分。本文详细地讨论了气调贮藏中温度、湿度的控制要求、控制方式 ,以及实现气调库气密性的措施。     

预应力混凝土无梁楼盖结构在冷库中运用的建议

鉴于目前国内冷库发展状况,文中分别对预应力混凝土无梁楼盖结构及冷库中无梁楼盖结构进行了分析,提出了在冷库结构中采用预应力混凝土无梁楼盖结构体的建议,并结合实际冷库设计经验给出设计中应注意的问题。     

冷库设计中氨制冷系统的安全与防护

氨作为制冷系统的“环保工质”广泛应用在冷库、食品加工、啤酒、饮料、石油化工等工程项目中。在冷库设计中,氨制冷系统的安全十分重要,采用积极有效的安全和防护措施,保证制冷氨系统安全和无故障运行,保护人身和财产安全,保护环境,充分体现以人为本的宗旨。本文系统论述了当前冷库设计中氨制冷系统的安全与防护设计要求及相关做法,对国外氨制冷系统安全防护状况也作出了介绍。     

近红外光谱尿液分析仪的原理及实现

分析了现有尿液成分分析方法,结合光谱仪工作原理和光机电设计理论,提出一种基于近红外光谱的无试剂尿液分析仪。该分析仪采用4个LED光源固定分布在圆形转盘上,系统控制步进电机带动圆盘转动实现LED循环透射样品,高速型InGaAs光电二极管作为检测器;单片机控制软件采用C51语言编制,实现对电路各模块的功能驱动;PC上位机软件采用VC++6.0编写,实现对数据采集卡传输的数据进行存储、图形显示及尿液成分分析。     

探讨信息产品加网络服务创造的价值

一、信息产品的特征信息产品的特征大致可归纳为“5i”,如图1所示。这类产品融合了当今最前沿的科学技术研究、网络研究、智能研究、互动研究、创意发明、心理学研究、工业设计研究等学科领域的智慧,是信息化时代的产物。     

基于搜索路径结构创新下的Apple APP Store再设计

目的对经典的Apple APP Store进行再设计的意义并不是对其予以否定,而是以此为研究对象,从人性化的角度进行设计探讨。方法安排测试人员围绕搜索效率与搜索兴趣两方面,对苹果在线商店进行感性体验与命题搜索体验,再用比较法分析Apple APP Store的部分设计特点,确定多条路径导向一个下载页面的思路后,又调整网站的搜索路径与页面视觉分区,并通过用户测试完成再设计。结论充分重视用户的操作行为,不断分析用户在产品体验过程中的认知变化以便拓宽设计思路,把脉设计痛点并找到设计途径。     

A particle swarm optimizer for constrained multi-objective engineering design problems

This article presents a particle swarm optimizer (PSO) capable of handling constrained multi-objective optimization problems. The latter occur frequently in engineering design, especially when cost and performance are simultaneously optimized. The proposed algorithm combines the swarm intelligence fundamentals with elements from bio-inspired algorithms. A distinctive feature of the algorithm is the utilization of an arithmetic recombination operator, which allows interaction between non-dominated particles. Furthermore, there is no utilization of an external archive to store optimal solutions. The PSO algorithm is applied to multi-objective optimization benchmark problems and also to constrained multi-objective engineering design problems. The algorithmic effectiveness is demonstrated through comparisons of the PSO results with those obtained from other evolutionary optimization algorithms. The proposed particle swarm optimizer was able to perform in a very satisfactory manner in problems with multiple constraints and/or high dimensionality. Promising results were also obtained for a multi-objective engineering design problem with mixed variables.     

Auto Store仓储系统的运作与效率优化研究

目的 为缓解零售电商商品仓库占地面积广,拣选效率受限等问题。方法 文中就存储策略、指派策略以及路径策略方面对Auto Store仓储系统进行详尽的介绍,在此基础上流程化的分析Auto Store系统完成单次订单拣货作业的业务流程,并运用Anylogic软件对所提出的模型进行仿真和验证。结果 假定订单到达服从Erlang分布,在拣选车和工作站数量和拣选货物数量相同的情况下,对比了Auto Store仓储系统混存布局和传统布局的拣选效率,验证了混存布局的可行性。结论 同时对比基于2种任务指派策略,得出了以基于拣选时间最小化的指派策略下系统运作效率更优这一结论,对理论分析与仿真研究之间的结果进行分析比较,验证了模型的有效性。     

A hybrid of back propagation neural network and genetic algorithm for optimization of injection molding process parameters

This paper presents a hybrid optimization method for optimizing the process parameters during plastic injection molding (PIM). This proposed method combines a back propagation (BP) neural network method with an intelligence global optimization algorithm, i.e. genetic algorithm (GA). A multi-objective optimization model is established to optimize the process parameters during PIM on the basis of the finite element simulation software Moldflow, Orthogonal experiment method, BP neural network as well as Genetic algorithm. Optimization goals and design variables (process parameters during PIM) are specified by the requirement of manufacture. A BP artificial neural network model is developed to obtain the mathematical relationship between the optimization goals and process parameters. Genetic algorithm is applied to optimize the process parameters that would result in optimal solution of the optimization goals. A case study of a plastic article is presented. Warpage as well as clamp force during PIM are investigated as the optimization objectives. Mold temperature, melt temperature, packing pressure, packing time and cooling time are considered to be the design variables. The case study demonstrates that the proposed optimization method can adjust the process parameters accurately and effectively to satisfy the demand of real manufacture.     

Nonconvex optimization of desirability functions

Desirability functions (DFs) are commonly used in optimization of design parameters with multiple quality characteristic to obtain a good compromise among predicted response models obtained from experimental designs. Besides discussing multi-objective approaches for optimization of DFs, we present a brief review of literature about most commonly used Derringer and Suich type of DFs and others as well as their capabilities and limitations. Optimization of DFs of Derringer and Suich is a challenging problem. Although they have an advantageous shape over other DFs, their nonsmooth nature is a drawback. Commercially available software products used by quality engineers usually do optimization of these functions by derivative free search methods on the design domain (such as Design-Expert), which involves the risk of not finding the global optimum in a reasonable time. Use of gradient-based methods (as in MINITAB) after smoothing nondifferentiable points is also proposed as well as different metaheuristics and interactive multi-objective approaches, which have their own drawbacks. In this study, by utilizing a reformulation on DFs, it is shown that the nonsmooth optimization problem becomes a nonconvex mixed-integer nonlinear problem. Then, a continuous relaxation of this problem can be solved with nonconvex and global optimization approaches supported by widely available software programs. We demonstrate our findings on two well-known examples from the quality engineering literature and their extensions.     

多载荷多工位转盘拓扑优化设计

基于拓扑优化理论,以结构总质量最小为目标,利用SIMP材料插值方法,结合HyperWorks/Optistruct拓扑优化功能对自动化组装设备中常用的多工位转盘进行了拓扑优化．根据优化后的重构模型与原始结构模型的静力学对比分析知,优化后降低了多工位转盘的总质量,提高了多工位转盘的刚度,同时减小了多工位转盘的局部最大应力．数据结果表明本方法对多工位转盘优化设计是有效的．