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51.
根据手机前盖的结构特点和质量要求,运用Moldflow软件对产品浇注系统、冷却系统进行优化设计。通过正交试验,分析了注射工艺参数对产品体积收缩率和翘曲变形的影响规律,得到优化注射工艺方案。根据Moldflow分析结果,利用UG软件完成产品的模具设计。  相似文献   
52.
This paper presents a metal hydride (MH) actuator rescue jack that uses hydrogen-absorbing alloy as its pressure source. The MH actuator is attached to a thin and flexible fiber-reinforced rubber bag end effector, enabling it to pry open narrow and rough gaps. The proposed MH rescue jack was prepared with different amounts of alloy (6–15 g). The results showed that, with only 6 g of alloy, the rescue jack was able to jack up a 100 kg weight to a height of 10 mm within 1 min by heating the alloy container to 50 °C. Moreover, the jack-up speed increased as the amount of alloy increased. A mathematical model was derived from the jack-up operation tests to estimate the jack-up height, with the aim of designing appropriate amounts of hydrogen-absorbing alloys for rescue jack development. According to the experimental results, the response of the jack-up height was modeled as a first order system in time domain. The model was defined as a function of alloy amount, and its validity was assessed by comparing the experimental and simulation results. The results were in good agreement which confirmed the potential of the proposed model as a design tool for jacks from the viewpoint of time constant.  相似文献   
53.
《Soils and Foundations》2019,59(5):1537-1551
Drainage is one of the most popular protecting measures to mitigate ground liquefaction. Deploying the drains horizontally may be convenient where conventional vertical ones cannot be used, like beneath existing structures. The spacing among drains must be designed to limit the pore pressure build-up during shaking. The usual assumptions of radial consolidation around vertical drains, stemming from the assumption of an infinite number of drains, may not be appropriate for horizontal ones, since the latter are generally arranged in few rows at a shallow depth, especially if drainage at the ground level is possible as well. Hence, existing solutions for vertical “earthquake” drains have been modified in this work to take into account such different geometrical features. The resulting solution has been validated against numerical and experimental sets of data. Charts covering a wide range of geometrical layouts, soil properties, and seismic actions are finally proposed. They can be used to design the drain spacing that is needed so as not to exceed the target value of excess pore pressure in the ground.  相似文献   
54.
To overcome the challenges of reconstructive microsurgery, a teleoperated robot called ASTEMA was built to help surgeons performing microanastomoses. The surgeons’ needs are first analyzed then the design steps are summarized. This robot is composed of three orthogonal linear actuators and a spherical wrist with its remote center of motion at the instrument tip. Geometric model of the spherical wrist was calibrated through mathematical optimization in order to compensate for imperfections of machining and assembling. Two preliminary experiments were carried out to assess the ASTEMA performance. The first was performed with a simple circular position trajectory. The second was a complex angular trajectory. Results show a significant improvement of gesture precision with respect to manual trajectory execution. They also show that subjects instinctively compensate the errors from the non-ideal wrist, thanks to visual feedback from microscope.  相似文献   
55.
Online knowledge-sharing communities typically acknowledge their top contributors by implementing recognition systems. Extant recognition systems suffer from several limitations such as treatment of the entire community as homogeneous and inflexibility of customization. We propose a framework based on socio-technical design principles for designing a multi-criterion- and multi-segment-based recognition system that exploits multiple user characteristics for differential recognition according to community goals. We apply this framework on data gathered from Yelp.com and show how it can be used to recognize top members of different identified behavioral segments (amateurs, adepts, and enthusiasts) based on their performance on various relevant factors.  相似文献   
56.
工程教育是我国高等教育的重要组成部分,工程教育认证已成为中国高校新的风向标,也成为高考生选择报考专业的一项重要指标。设计模式是计算机科学与技术专业的一门核心课程,包含了面向对象的精髓,是软件体系结构的基础,在工程教育认证所评估的课程设置中起着承上启下的关键作用。本文基于工程教育专业认证理念,以及山东农业大学申请认证所用的《计算机科学与技术专业培养方案》,从教学内容、教学方式、课程目标与毕业要求对应关系、解决复杂工程问题能力、教学进度安排等方面,对设计模式课程开展了教学研究,并将该教学方案应用于本科教学。  相似文献   
57.
生活陶艺涉及了陶艺、日用陶瓷设计、工业设计等,本文将从设计的角度来探索生活陶艺最具特色的两个部分--审美与形式。人性化设计包含个性设计、人文设计、绿色设计。本文将引用人性化设计中的个性化设计与人文设计中的来论述生活陶艺的功能与情感设计的运用。  相似文献   
58.
当复杂形式的建筑设计日益普遍,几何学对于建筑师理解复杂建筑形体的操作实质变得前所未有的重要,并以此催发几何学与建筑学关联性的重新审视。本文从梳理两者关系的演变历程出发,分析了当代数字化建筑实践的4种几何建构策略——几何生形、几何转化、协同模拟和几何重构,并结合具体案例研究,指出面向建筑本体需求的数字化几何思维是建筑学传统的回归,可以为数字化建筑设计提供更为合理的认识和参考。  相似文献   
59.
The aim of this work is the design of a pitot probe (PP) prototype in order to retard the cool down of the tip, in case of a heating element failure. The viability of operation in flight conditions is evaluated. The design consists of a redundant heating system incorporating phase change materials (PCM). Combining experimental observations of ice formation with the implementation of the conjugate heat transfer (CHT) model, with the addition of the heat release due to the phase change of the PCM, the numerical evaluation is developed. The modelling assumptions and numerical implementation of the phase change process are presented. Then, the selection an appropriate PCM is based on the low flammability and volume dilation and the quantitative effects of the material properties on the heat transfer. A commercial PCM solution based on salt hydrates was chosen as the most adequate for the design. The parametric design of the prototype, based on the design of experiment method and fractional factorial testing, is established. A multiple linear regression model was obtained in order to maximize the cooling retardation. The numerical simulations demonstrate that the prototype PP tip temperature remains 194 s longer above 0 °C than that of the conventional model analyzed.  相似文献   
60.
殷彦斌  张宏亮 《机械制造》2020,58(2):10-13,19
为了预防自动扶梯发生安全事故,设计了一种基于人工智能的自动扶梯智能安防系统。这一系统利用视频数据采集平台采集乘客数据,应用机器视觉及人工智能技术对乘客的姿态与行为进行主动识别,针对乘客的危险行为给出异常报警,在出现危险状态时触发声光报警器,控制自动扶梯减速或停止运行。这一系统通过有线或无线网络将数据传输至云平台,监管部门可基于手机客户端进行实时监控。特种设备监督管理部门、检验机构、维护保养单位、产权单位等可通过这一系统掌握自动扶梯运行状况。应用所设计的自动扶梯智能安防系统,可以显著提高自动扶梯安全事故预防水平和应急处理能力。  相似文献   
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