燃气灶点火定时开关的设计

设计制作一种机械式燃气灶定时开关,可以根据使用者预先设定的时间到时准确关闭,从而能够达到杜绝厨房安全隐患的目的。本设计利用外接的定时器对燃气灶进行时间控制,通过机械结构的传动准确关闭点火开关。其特点是工作稳定,受环境影响小,成本低,安装方便等。     

双级全预混燃气灶引射器的理论分析

提出的一种双级全预混引射器是燃气灶实现全预混燃烧的重要部件。以燃烧功率为3. 5kW的民用天然气燃气灶为例,建立了双级引射器的理论模型,分析了引射比、截面比、引射压差等对引射器性能的影响。结果显示:引射器存在一最佳截面比使被引射流体压差最高,最佳截面比随引射比的增加而增大,且不受引射压差的影响;被引射流体压差随引射器截面比的增大呈先快速增加后小幅下降的趋势,且受引射比和截面比的影响逐渐减弱。一、二级引射比分别为μ_1=1. 2、μ_2=9. 3时,双级全预混燃气灶引射器的最佳截面比为k_1=15、k_2=130,此时的引射器性能较好,结构较优。     

自动节能环保安全燃气灶的设计与应用

通过对市场上现有燃气灶的调查研究,提出了“锅起火灭,锅落火起”的节能新方案,火苗不会因为外界环境因素（风吹、水淋等）意外熄灭造成燃气泄漏;采用更方便快捷的点火方式,设计了更节能、环保、安全的优化机构。经过模型设计及试验分析计算,此新型燃气灶达到了节能、便捷、安全的效果。     

一种节能环保抽油烟机清洁装置的设计

该文设计了一种利用燃气灶未利用的废热产生高压蒸汽对抽油烟机内部油污进行清理的装置.它包括供水模块,蒸汽发生模块和除油模块.该装置弥补了现有蒸汽除油产品高能耗而且需要对抽油烟机拆卸后才能对其进行油污清理的缺点,是一种无需外加能源、装载在抽油烟机内部、不用拆卸且自动清理抽油烟机内部油污的高效蒸汽除污装置.     

大尺寸球面加工装置

球面加工一直是决定轴流泵产品质量的关键因素。充分利用卧式车床的结构特点，设计了一种新型的大尺寸球面加工装置，并对其结构特点、工作原理、使用注意事项进行了介绍。     

螺旋压力机上带锻件顶出结构的锻模设计

锻件生产中成品顺利出模有着重要的现实意义.文中通过带顶出结构模具的设计及改进,充分利用了现有设备,同时也为此类设备上锻模设计工作摸索出一种基本设计方法及思路,积累一些前期设计经验.     

带有延时熄火装置的家用燃气炉

目前所使用的家用燃气炉,主要由炉台、炉头、煤气管接嘴、电子打火器构成,为防止泄漏,燃气灶必须加装熄火保护装置.论文提供了一种能在使用中人为地事先设定燃烧时间,延时关闭煤气通路,避免因忘记关炉而发生事故的带有延时熄火装置的家用燃气炉.该设计已获国家实用新型专利.     

活塞式制冷压缩机的参数化设计

提出一种基于约束网络图的参数化设计方法，并把它应用于活塞式制冷压缩机的计算机辅助设计。该方法可充分利用已有的压缩机同类产品的成熟结构，可减少活塞式制冷压缩机的设计绘图时间。     

新型秸秆撕裂粉碎机的设计

目前食用菌生产的原材料资源不断开发,为了充分利用农业废料,设计了一种利用动定锯齿结构对稻草等秸秆进行较细撕切粉碎的加工机械,能够用作食用菌的原料,大大提高了稻草的利用率.     

一种密集移动车库的制造装配与调试

为解决传统自行车停车装置无法充分利用水平空间,基于密集书库的原理,设计了一种密集移动车库,该车库采用模块化设计,每个模块主要包括两大部件:停车固定装置和停车底板,其制造装配与调试主要围绕这两大部件展开,该停车装置能够充分利用水平空间,方便停车取车。文中介绍了密集移动车库的整体结构、制造方法、装配方式、调试过程以及密集移动车库的应用前景。     

Minimal Realization of Linear Graph Models for Multi-physics Systems

An engineering system may consist of several different types of components,belonging to such physical"domains"as mechanical,electrical,fluid,and thermal.It is t...     

INTEGRAL EQUATION METHOD＇S APPLICATION IN HOLE-EDGE STRESS OF COMPOSITE MATERIAL PLATE WITH DIFFERENT SHAPED HOLES

The strength of composite plate with different hole-shapes is always one of the most important but complicated issues in the application of the composite material. The holes will lead to mutations and discontinuity to the structure. So the hole-edge stress concentration is always a serious phenomenon. And the phenomenon makes the structure strength decrease very quickly to form dangerous weak points. Most partial damage begins from these weak points. According to the complex variable functions theory, the accurate boundary condition of composite plate with different hole-shapes is founded by conformal mapping method to settle the boundary condition problem of complex hole-shapes. Composite plate with commonly hole-shapes in engineering is studied by several complex variable stress fimction. The boundary integral equations are founded based on exact boundary conditions. Then the exact hole-edge stress analytic solution of composite plate with rectangle holes and wing manholes is resolved. Both of offset axis loadings and its influences on the stress concentration coefficient of the hole-edge are discussed. And comparisons of different loads along various offset axis on the hole-edge stress distribution of orthotropic plate with rectangle hole or wing manhole are made. It can be concluded that hole-edge with continuous variable curvatures might help to decrease the stress concentration coefficient; and smaller angle of outer load and fiber can decrease the stress peak value.     

Non-monotonic material contrast in scanning ion and scanning electron images

30 keV Ga⁺ focused ion beam induced secondary electron (iSE) imaging was used to determine the relative contrast between several materials. The iSE signal compared from C, Si, Al, Ti, Cr, Ni, Cu, Mo, Ag, and W metal layers does not decrease with an increase in target atomic number Z₂, and shows a non-monotonic relationship between contrast and Z₂. The non-monotonic relationship is attributed to periodic fluctuations of the stopping power and sputter yield inherent to the ion–solid interactions. In addition, material contrast from electron-induced secondary electron (eSE) and backscattered electron (BSE) images using scanning electron microscopy (SEM) also shows non-monotonic contrast as a function of Z₂, following the periodic behavior of the stopping power for electron–solid interactions. A comparison of the iSE and eSE results shows similar relative contrast between the metal layers, and not complementary contrast as conventionally understood. These similarities in the contrast behavior can be attributed to similarities in the periodic and non-monotonic function defined by incident particle–solid interaction theory.     

Application of Feature Extraction through Convolution Neural Networks and SVM Classifier for Robust Grading of Apples

This paper proposes a novel grading method of apples,in an automated grading device that uses convolutional neural networks to extract the size,color,texture,an...     

分布动态载荷识别的抗噪处理

针对正交多项式频域法在用多种响应对矩形薄板进行载荷识别中抗噪性较差的问题,综合运用平均法、矩阵预处理和奇异值截断法等方法对之进行改善,并引入空间映射的思想,将该方法的应用范围拓展为复杂的模型.利用仿真算例,证实了该方法具有较好的抗噪性.     

基于MELTAC-N平台的核电厂安全级DCS环网研究与测试

针对工程实践中环网通讯相关问题的处理缺乏理论基础及国产化安全级DCS平台的开发缺乏成熟经验借鉴问题,对基于MELTAC-N平台核电厂安全级DCS环网的软硬件实现进行了研究。提出了安全级DCS环网双环网冗余设计、光切换开关设计等硬件设计方法,以及以RPR协议为基础,采用全数据收发策略的软件设计方法。在CPR1000安全级DCS平台上对安全级DCS环网的可靠性及实时性进行了评价,并进行了容错能力、响应时间及响应时间稳定性测试验证实验。结果表明,基于MELTAC-N平台安全级DCS环网软硬件设计具有较好的容错能力及响应时间稳定性。     

Short-Term Relay Quality Prediction Algorithm Based on Long and Short-Term Memory

The fraction defective of semi-finished products is predicted to optimize the process of relay production lines, by which production quality and productivity ar...     

End-to-End Multiview Gesture Recognition for Autonomous Car Parking System

The use of hand gestures can be the most intuitive human-machine interaction medium.The early approaches for hand gesture recognition used device-based methods....     

The laboratory simulation of abrasive wear

Abrasive wear has long been recognised as one of the most potentially serious tribological problems facing the operators of many types of plant and machinery; several industrial surveys have indicated that wear by abrasion can be responsible for more than 50% of unscheduled machine and plant stoppages. Locating the operating point of a tribological contact in an appropriate operational ‚map’︁ can provide a useful guide to the likely nature and origins of the surface degradation experienced in use, though care must be exercised in choosing the most suitable parameters for the axes of the plot. Laboratory testing of materials and simulations of machine contacts are carried out for a number of purposes; at one level for the very practical aims of ranking candidate materials or surface hardening treatments in order of their wear resistance, or in an attempt to predict wear lives under field conditions. More fundamentally, tests may be aimed at elucidating the essential physical mechanisms of surface damage and loss, with the longer term aim of building an analytical and predictive model of the wear process itself. In many cases, component surface damage is brought about by the ingress of hard, particulate matter into machine bearing or sealing clearances. These may be running dry although, more usually, a lubricant or service fluid is present at the interface. A number of standardised wear test geometries and procedures have been established for both two- and three-body wear situations, and these are briefly described. Although abrasive wear is often modelled as following an ‚Archard’︁ equation (i.e. a linear increase in material loss with both load and time, and an inverse dependence on specimen hardness) both industrial experience and laboratory tests of particularly lubricated contacts show that this is not always the case: increasing the hardness differential in an abrasively contaminated lubricated pair may not always reduce the rate of damage to the harder surface.     

Limits of topographic measurement by the scanning tunnelling and atomic force microscopes

Parameters describing the topographic character of a surface (height, surface wavelength, slope and curvature) can be derived from equivalent sinusoidal profiles. The response of a surface-measuring instrument may be modelled in terms of instrument parameters such as stylus radius, and scanning range and resolution. The performance of the instrument may then be mapped as a zone in amplitude-wavelength (AW) space to show the sinusoidal profiles it is capable of measuring. In a first-order analysis the STM and AFM are considered as equivalent to contact-stylus instruments with a notional stylus radius equal to the tip radius plus the gap. Comparisons between different instruments and types of instrument are readily made by mapping in AW space. The error arising from convolution of the sinusoidal profile with that of the finite tip may be quantified and plotted as contours in AW space.