共查询到20条相似文献,搜索用时 46 毫秒
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根据CO2气体对红外线的吸收特性,利用红外吸收传感器设计了一种CO2气体的检测方法,详细阐述了其工作原理,并对系统进行了硬件电路和软件框图设计。红外吸收法测定CO2浓度实现了对CO2气体的高精度、高选择性的检测,具有测量范围宽、灵敏度高、响应时间快、选择性好、抗干扰能力强等特点,具有广泛的应用前景。 相似文献
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建立了基于光谱吸收技术的检测系统,用于快速、准确地测量N2O气体浓度。首先,从理论上证明了二次谐波、一次谐波与N2O气体浓度之间的关系;然后,设计了痕量N2O气体浓度检测系统,利用光源调制、锁相放大等技术,实现了强杂波背景下气体浓度弱信号的解析;最后,实验测试了系统的检测性能、抗干扰能力及检测结果的可重复性。测试结果表明,系统能够在0~1%有效检测N2O气体浓度,检测下限为5.0×10-5,相对检测误差为0.11%,检测结果线性方程为Y=192.699 09 X-0.006 24,线性度为0.998 07。多次检测实验表明,系统相对标准偏差为0.137%,CO2、O2、水蒸气等常见气体对检测结果无影响。改变激光器的中心波长,该方法亦可用于CO2,CH4等其它温室气体的检测。 相似文献
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非分光红外CO浓度探测系统 总被引:2,自引:0,他引:2
介绍了基于非分光红外(NDIR)原理的CO浓度探测系统总体设计.采用新型红外光源和探测器对系统光学部分进行设计,通过低频电调制取代传统机械调制方法.讨论了光源恒压供电系统和信号滤波放大处理电路,开展了大量的实验验证研究.实验结果表明该CO浓度探测系统准确可靠,可以满足工况场合下CO气体浓度测量分析的需求. 相似文献
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基于红外吸收型智能CO_2浓度分析仪 总被引:1,自引:1,他引:0
基于环境监测部门和工业现场对二氧化碳浓度精确测量的需要,文中根据红外吸收原理和Lamber-Beer定律,将调制光源和红外传感器应用于CO2浓度分析仪器中,设计了一种新型CO2气体浓度分析仪。文中简要说明了整个系统的架构,详细介绍了系统硬件和软件驱动程序设计以及调制光源、传感器信号与气体浓度的关系。该分析仪具有自动量程切换、声光报警、远程通信等功能,可以对检测现场进行实时、远程监控。设计的分析仪精度高、稳定性好、响应速度快、体积小。 相似文献
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基于红外传感器的CO2气体检测电路设计 总被引:1,自引:1,他引:0
白泽生 《仪表技术与传感器》2007,(3):59-60
利用红外吸收型CO2气体传感器设计了一种CO2气体检测电路,详细阐述了其结构和工作原理。该电路具有测量范围宽、灵敏度高、响应时间快、抗干扰能力强等优点,简单易用,快速直读,价格低廉,具有较好的应用前景。 相似文献
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本文介绍了一种基于CAN总线的车内空气质量控制节点设计方法.本设计采用PHILIPS公司的P89C58单片机、独立CAN控制器SJA1000、CAN收发器PCA82C250,开发了一款带空气质量传感器的通用车载CAN总线控制节点.利用控制节点数据采集功能实时监控车内CO、CO2气体浓度,当气体浓度轻度超标时进行声光报警提醒驾乘人员;当气体浓度重度超标时节点与车载CAN总线通讯,发送CAN控制数据帧,实现自动开窗通气.经实际验证,设计的车内空气质量控制节点可灵活、方便的安装在装备车载CAN总线的车型上,提高了汽车使用安全性能,有效防止车内CO、CO2气体对驾乘人员的伤害和事故发生. 相似文献
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Clarence W.DE SILVA 《Instrumentation》2019,(4):72-84
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... 相似文献
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INTEGRAL EQUATION METHOD'S APPLICATION IN HOLE-EDGE STRESS OF COMPOSITE MATERIAL PLATE WITH DIFFERENT SHAPED HOLES 总被引:1,自引:0,他引:1
LI Cheng ZHENG Yanping 《机械工程学报(英文版)》2008,21(6):115-118
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. 相似文献
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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. 相似文献
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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... 相似文献
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分布动态载荷识别的抗噪处理 总被引:2,自引:2,他引:0
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. 相似文献
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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。 相似文献
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The fraction defective of semi-finished products is predicted to optimize the process of relay production lines, by which production quality and productivity ar... 相似文献
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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.... 相似文献
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J. A. Williams 《Lubrication Science》1997,3(3):267-306
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. 相似文献
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M. Stedman 《Journal of microscopy》1988,152(3):611-618
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. 相似文献