车载瞄准设备升降系统设计

为了适应市场的需要,出现了车载式瞄准设备.其中瞄准机座是瞄准设备的支撑和定位装置,通过控制安装在机座上的瞄准系统,使它能够按照预定的规律或者跟随目标运动,准确地指向目标;并且通过它精确地测出目标的方向.为了减小树木、房屋等低高度近距离障碍物对瞄准设备的遮蔽,通常应采取措施将其举高架设.对于要求架设时间短的车载瞄准设备来说,必须设计出自动升降系统,以实现快速便捷地升高设备的目的.     

AFC车站系统设备布局调整工程可行性分析

为了满足车站客流组织和安全运营的需要,通过提高AFC设备使用效率,以便更好服务乘客,以提高地铁的运营服务水平。对现有运营车站AFC设备布局重新进行设计,对工程做出详细指引。达到优化各车站的设备布局和设备数量,指导完成各站AFC设备的布局调整。在已运营线路的车站开展布局调整工程,对车站运营有较大影响,对工程质量也有更高的要求。为了保证AFC布局调整工程顺利高效的完成,对AFC布局调整工程的可行性做出分析和指引是十分必要的。     

可溶性阳极快速刷镀Ni-P合金镀层结构及性能研究

论述Ni P合金快速刷镀液的配方 ,研究可溶化金属阳极电沉积刷镀工艺 ,分析可溶化金属阳极电沉积刷镀层性能。采用可溶化金属阳极在零部件上刷镀Ni P合金具有刷镀层硬度高 ,耐磨性好 ,有广泛的应用前景。     

提高极限拉延比的方法探讨

依据极限拉延比、极限拉延系数、极限直径减小比之间的关系以及压料力对极限拉延比的影响,分析得出通过干膜润滑剂提高凸模的摩擦力、提高压边圈和凹模工作表面光洁度、周边退火拉延法等措施,探讨了提高极限拉延比的方法。     

新型环保烧烤炉

新型环保烧烤炉不仅可以节省木炭,还能起到减污减排的效果：它采用侧旋风烧烤食物．使产生的一部分油烟注入到炭中继续燃烧可以节省木炭约25％：它利用炭火的余热产生水蒸汽处理另一部分油烟。最终,使我们的产品达到节能减排的效果。     

Calibration and analysis of spatially resolved x-ray absorption spectra from a nonuniform plasma

We report here the calibration and analysis techniques used to obtain spatially resolved density and temperature measurements of a pair of imploding aluminum wires from x-ray absorption spectra. A step wedge is used to measure backlighter fluence at the film, allowing transmission through the sample to be measured with an accuracy of ±14% or better. A genetic algorithm is used to search the allowed plasma parameter space and fit synthetic spectra with 20?μm spatial resolution to the measured spectra, taking into account that the object plasma nonuniformity must be physically reasonable. The inferred plasma conditions must be allowed to vary along the absorption path in order to obtain a fit to the spectral data. The temperature is estimated to be accurate to within ±25% and the density to within a factor of two. This information is used to construct two-dimensional maps of the density and temperature of the object plasma.     

简易数控车床纵向伺服进给系统的设计

本文提出了一种简易数控车床纵向伺服进给系统的设计方法,具体包括:总体方案的确定、滚珠丝杠螺母副的设计及计算、传动比的确定、齿轮参数的计算、步进电机的计算及选取等,最后对伺服进给系统控制器的设计给出了一种可行方案。     

有关电子俘获检测器污染后的判定、清洗及维修案例分析

电子俘获是气相色谱分析中常用的的检测器（ECD）。它最易出现的问题就是受污染,轻则灵敏度降低,重则没有响应。处于对放射源的恐惧,人们往往敬而远之,不知该如何处理。所以,了解污染源、判定污染程度、掌握有效的清洗方法,这对用好仪器有着很大的帮助。通过一个故障实例的分析,更清晰的展示了整个维修过程。包括防止污染的办法、判断污染的步骤、清洗管路的连接、操作中的注意事项和技巧等。     

立身文化及立身教育

“立身”作为传统文化概念,与“立德、立功、立言”之“三不朽”有同等重要的意义。甚至更具基础性。人生在世,何以立身,以何立身,这是自古至今人们都要思考并践行的。从文化传统视角考察,立身在人们的观念和行为中实际上是对道的遵从、对德的坚守、对礼的维护、对孝的体认。“遵道”具有天人合一的意蕴,“守德”强调主体良心的发现,“从礼”注重社会规则的价值,“讲孝”旨在强化事父忠君的家庭--社会模式的同构。立身文化的积极意义在于促进人的社会化、维护社会的和谐稳定。而立身教育就是要从文化的角度解决人何所由何所之、人的善良本性如何激发、人的规则意识怎样建立、人的品性如何养成的问题。从根本上说,解决立身问题是中国传统文化传承和发展的一条重要轨迹。     

混流汽车总装配线上的零部件优化配送方案研究

配送车每次配送的利用率大小是提高配送效率的主要因素,因此设计一种启发式算法使配送车一次装载的标准塑料周转箱尽可能多,提高配送车空间利用率.最后的仿真实验验证了上述配送方法的实用性,提出的零部件配送管理方法,只需使用较少的配送工人,同时降低了线旁库存,能为企业节省人力,降低生产成本.     

Precision motion control with a high gain disturbance compensator for linear motors

In this paper, we address the problem relating to the precision control of permanent magnet linear motors to track repeated motion trajectories. A high gain disturbance compensator is developed to improve the control performance degraded due to the presence of significant disturbances. An inverse gain of the overall system model is used to set up a disturbance observer. The observed disturbance is then used to generate a "knocker" signal, to be augmented to the control signal, which can provide the additional energy necessary to overcome the effects of the disturbances. A learning scheme is used to adjust the knocker signal iteratively over the repeated cycles. Simulation and experimental results are furnished to demonstrate the effectiveness of the proposed control scheme.     

A cutting sequence optimization algorithm to reduce the workpiece deformation in thin-wall machining

A thin-wall part of lower stiffness can be subject to significant deformation during its cutting process. This study proposes a cutting process optimization algorithm to reduce the workpiece deformation. First, the volume to be removed is divided into a set of blocks. The proposed algorithm starts from the finished workpiece shape, with all the blocks removed. The objective of the proposed algorithm is to find a sequence of adding the blocks, such that the workpiece deformation is always smaller than the given threshold value when the cutting forces is imposed at each step. The workpiece deformation at each step is simulated by using the FEM (finite element method) simulation. By inverting the sequence of adding the blocks, the optimized sequence to remove the blocks can be obtained. Additionally, the block size can be modified to reduce the axial depth of cut to further reduce the workpiece deformation, or to increase the radial depth of cut to enhance the efficiency. Experiments are conducted to confirm the effectiveness of the algorithm to reduce the maximum workpiece deformation during the entire cutting process.     

高速铁路桥梁栏杆的机械化生产

根据我国武汉-广州铁路客运专线试验段工程施工的需要,对高速铁路桥梁栏杆机械化生产工艺和生产线进行了研究。通过相关生产工艺性试验,对目前国内普遍采用的混凝土产品生产基本工艺进行了指标检测和数据对比分析,创新性地提出了串联双效生产工艺,即预制件在浇注中先进行预振实,保证成品的密实度,离心成型时改善预制件的外观质量。同时结合工程施工实际,自行研制出了一条高速铁路桥梁栏杆机械化生产线,并介绍了机械化生产线的主要装置,其中包括隔柱、立柱、扶手生产线,主要设备包括离心成型机、振实台、模具拆装机具等,以及保障产品质量的生产过程控制。通过实践运用,高速铁路桥梁栏杆机械化生产线具有生产效率高、简单易操作,可靠稳定、维护费用低等优点。该生产线所生产的产品能满足栏杆结构受力与使用功能,具有外形美观、质量稳定可靠的特点。     

Analytical models of composite material drilling

Drilling of composite material structures is widely used for aeronautical assemblies. When drilling, damage to the composite laminate is directly related to the cutter geometry and the cutting conditions. Delamination of the composite materials at the hole exit as directly related to the axial force (F _Z) of the cutter is considered to be the major such defect. To address this issue, an orthotropic analytical model is developed in order to calculate the critical force of delamination during drilling and a number of hypotheses for loading are proposed. This critical axial load is related to the delamination conditions (propagation of cracks in the last layers) and the mechanical characteristics of the composite material machined. A numerical model is also drawn up to allow for numerical validation of the analytical approach. A comparison between these analytical and numerical modellings and experimental results from quasi-static punch tests led to the choice of the loading hypothesis closest to the experimental conditions. The selection of corresponding load permits to model the drilling critical thrust force on delamination and then to optimise the cutting conditions. The dimensions and geometrical shape of the cutter are of considerable importance when it comes to choosing this load. The present article focuses on the case of the twist drill, which is commonly used to drill thick plates. However, this work can be adapted to different cutter geometries.     

基于自适应变步长算法在大型非圆曲线零件数控加工中的应用

针对固定步长的圆弧插补算法在大型非圆曲线零件加工中的缺点，提出了自适应变步长算法，该方法按照曲线的曲率变化而采用相应的步长，算法简单，插补误差小，达到了快速、高效的加工效果，避免了以往过切或者加工精度不够的现象。能够提高数控机床的插补精度和加工效率。     

新型换热器管子管板焊接工艺的研究

管板堆焊镍基合金，换热管为铁素体钢管，管子管板接头为平齐式的换热器是一种新型结构的换热器。管子管板角焊缝的焊接采用A-GTAW焊接方法。通过实验发现，为了得到质量稳定、焊缝尺寸和形状能够满足设计和相关技术条件要求的焊接接头，在严格限制镍基合金和换热管杂质元素含量、合理选择焊接工艺参数、控制焊枪钨极与管壁相对位置的同时，应采取以下两方面工艺措施：一是焊前对待焊区进行严格的清理，去除油、锈等杂质污物；二是在焊接过程中对管板进行低温预热。     

液压增压注水泵的研究

分析了机械增压注水泵存在的问题，介绍了液压增压注水泵的结构、工作原理及所具备的排量可调等优点，并对液压冲击、噪声等问题进行了理论动态特性的分析。     

自行车机器人的控制

作为被控制对象的自行车双轮机器人是以自行车为基础,再配以转动车把的电机和驱动后轮的装置构成的。根据经验,当自行车行走不稳向两边倾倒时,人会向左或右转动车把,并且人的重心也会向右(或左)移动。向倾倒的方向转动车把的作用是将使车倾倒的重力的分力转用于车体做曲线运动的向心力,从而避免车体的倾倒。而骑车人调节自身的重心的作用,可以辅助起到将车体从倾倒的方向纠正回平衡点处的作用。     

基于因特网的远程家居自动控制系统研制

提出了一种基于因特网的远程家居自动控制系统解决方案,给出了系统各组成部分的硬件、软件详细设计与具体实现.系统由基于C8051F005单片机的嵌入式控制器和家居Web服务器组成,嵌入式控制器有8路A/D转换通道和32个I/O端口,用于连接传感器和控制家电设备,嵌入式控制器通过RS232串口同家居Web服务器进行通讯,Web服务器设有基于JSP技术构建的自动控制网站,用户可通过嵌入式控制器或WWW浏览器控制家电设备.系统采用动态DNS技术将动态IP地址映射为一个固定域名,通过此域名可方便地访问家居自动控制网站实现对家居的远程监控.系统扩展灵活、功能强,价格低廉.     

Journal bearing housing design—A statistical study with FEM

When designing journal bearing housings for construction equipment, one goal is to get an even pressure distribution over the length of the bushing. This is to avoid excessive wear due to contact pressure peaks.A housing that is considered good, does not allow the pin to deflect and keeps the stresses low in the weld. To do this it must be stiff and this will lead to high contact pressures on the edges of the bushing, which is not preferable since wear is highly dependent on the contact pressure level.If the distribution of the contact pressure could be smoothed out over the bushing, the material might be used more efficiently. The normal way to do this is to crown the bushing to allow for pin deflection. However this leads to reduced area in contact. Another method to avoid high pressures in the bearing is to optimize the bearing housing for optimum stiffness.This paper describes one way to optimize journal bearing housings in regard to the contact pressure in the tribo-contact. A statistical approach was applied to a parameterized finite element model with contact elements. Three parameters were analyzed at different loads; set ring thickness, set ring width and fillet weld size.The contact pressure distributions were evaluated in two different ways to a single value to meet the statistical demand of measurable result. The results show that the set ring thickness and width are the parameters that influence most the contact pressure distribution. To reduce the maximum contact pressure the set ring thickness should be kept small.