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1.
哈特曼-夏克传感器在非球面加工中的应用   总被引:9,自引:0,他引:9  
饶学军  凌宁  王成  姜文汉 《光学学报》2002,22(4):91-494
论述了哈特曼-夏克传感器的测量原理,对它的测量精度进行了标定。同时还介绍了哈特曼-夏克传感器的在光学车间实际测量大口径非球面系统的情况,表明哈特曼-夏克传感器是一种非常有效的光学车间检测手段。  相似文献   

2.
羰基镍分析报警仪运用化学发光原理构成,不仅适用于羰基镍生产车间现场的检测和报警,也适于实验室的研究工作。检出限达0.037mg/m^3(0.5ppb),响应时间2min。  相似文献   

3.
许玉枝  姜莉莉  张胜 《应用声学》2012,(6):1686-1688
通过物联网的原理和架构,对其关键技术进行研究,构建以物联网关键技术为基础的运营平台;对网络环境下的车间作业调度系统进行分析和研究,结合物联网技术平台,利用平台中的RFID等信息传感设备将采集到的车间底层信息通过无线传感器网络传送到中央信息系统,实现对待加工零件的实时信息采集和识别,进而通过开放式的计算机网络循环结构实现车间底层、管理层和用户层的信息交换和共享;车间现场数据采集的实时化、自动化和可视化使企业信息实现全程"透明"管理,实时监控生产加工过程,为企业在智能生产领域的长远发展提供了重要依据。  相似文献   

4.
在对经典遗传算法进行研究的基础上,针对具有等待时间置换流水车间调度问题,以最小化最大完成时间为优化目标建立整数规划模型,并提出一种解决该问题的IGA算法。算法中部分染色体的初始种群由原问题所转化而成的具有等待时间两台机器的置换流水车间调度问题的解所组成。交叉方法采用基于顺序和位置相结合的OPX方法。通过对Taillard算例中置换流水车间调度问题基准数据的测试,并对仿真实验的结果进行了分析,验证所提出IGA算法的有效性和可行性。  相似文献   

5.
刘露  陈于  常晓娟 《光谱实验室》2013,30(5):2414-2417
采用热解吸气相色谱法分别测定皮鞋厂成型车间、缝制车间和配料车间空气中的苯含量.用活性炭吸附管采集样品,并放入热解吸仪中加热,通氮气解吸出苯,用气相色谱仪FID检测器分析.结果表明,采样量为10L时,热解吸气相色谱法的平均解吸效率为97.5%,精密度和灵敏度均较高,适用于工作场所中苯浓度的测定.检测数据显示3个场所的苯浓度均符合国家标准.  相似文献   

6.
林健  王敏  韩振华  卓金寨 《应用光学》2012,33(6):1053-1057
为了实现车间球面镜片的半径偏差的在线无损检测,基于激光检测技术,提出了一种无需精密导轨的小型球面干涉仪系统的设计方案,并对整个系统的检测原理进行了分析。通过Zemax软件模拟的分析验证,该系统不仅可以测出球面面形的像散偏差和局部偏差,而且还可以快速测出球面镜的半径偏差,其演算测得的曲率半径精度优于0.01%。与目前已有的球面干涉仪相比较,具有系统结构紧凑、无精密导轨、操作效率高和低成本的特点,特别适用于车间的在线非接触检测。  相似文献   

7.
多速度差模型及稳定性分析   总被引:20,自引:0,他引:20       下载免费PDF全文
王涛  高自友  赵小梅 《物理学报》2006,55(2):634-640
在全速度差(Full Velocity Difference, FVD)模型的基础上,提出了一个扩展模型——多速度差(Multiple Velocity Difference, MVD)模型. 在MVD模型中,尝试利用多辆前车信息以提高交通流的稳定性,除了考虑前车与本车的速度差外,进一步利用了多辆前车间的速度差信息. 通过线性稳定性分析,对两个模型进行比较,发现在MVD模型中,自由流稳定的敏感系数临界值变小,稳定区域有明显增加. 数值仿真结果表明,MVD模型能有效地抑制交通流堵塞. 关键词: 交通流 稳定性分析 速度差 节能  相似文献   

8.
制作了可用于纺织细纱车间的折板式间接蒸发冷却器试验台,通过实验研究来分析折板式间接蒸发冷却器在纺织细纱车间应用时的主要影响因素。首先借助于正交实验表,通过9组实验来分析折板式间接蒸发冷却器的三种主要影响因素对折板式间接蒸发冷却器的换热效果的显著程度。然后引入单因素实验的研究方法,在保证其它影响因素为最优的情况下,研究某一主要影响因素变化导致换热效率变化的规律,为实际工程的设计和节能运行调节提供理论依据。  相似文献   

9.
为给卷烟厂生产车间选择适宜的冬季供冷模式,文中对三种供冷模式即冷水机组供冷、加大空调新风比以及冷却塔供冷的特点进行了对比分析,并以杭州卷烟厂为例,通过对其生产车间冬季供冷需求和上述三种供冷模式的能耗状况进行定量模拟计算,发现冷却塔供冷是一种最为节能的冬季供冷模式。同时对杭州卷烟厂实际实施的冷却塔供冷系统的运行数据进行了监测,结果表明该系统在监测期内(2011年12月24日到2012年3月6日),与冷水机组供冷相比,总计节约电量约为69万度,节能率为61.9%,季节冷源系统能效系数达10.6。该文研究对于卷烟厂生产车间冬季供冷模式的选择具有一定的指导和参考意义。  相似文献   

10.
在织造车间降噪上应用“吸声吊顶”的实效   总被引:2,自引:0,他引:2       下载免费PDF全文
沈仁 《应用声学》1985,4(1):41-44
我国目前纺织厂织造车间的噪声级均较高.应用吸声降噪原理,经四年多来的探研,通过模拟、中试和二顶试点三步的实践证明,对厂房建筑上进行声学处理,即架设大面积“强吸声吊顶”技术的方法,能使织造车间的噪声降低4—6dB(A),收到较好的降噪效果,受到工人们的欢迎.为纺织工业的织造车间噪声治理提供了实践经验.  相似文献   

11.
Based on the analysis of active noise control system with multi-channel monopole secondary sources, a kind of compound secondary source is proposed in this paper. The proposed compound secondary source consists of two closely located monopole sources with their distance much smaller than a wavelength. The characteristics of the compound source are analyzed, and the performances of the active noise control system with the compound secondary sources on the monopole primary sound field and sound radiated by a plate are investigated both numerically and experimentally. It has been found that the proposed compound secondary sources control system can provide higher noise reduction for free field noise radiation control with the same number of control channels. It is shown that the better performance in noise reduction of the compound secondary sources control system is mainly due to the directivity of the secondary sources where the energy radiation pattern of the compound sources is similar to that of the primary sources.  相似文献   

12.
13.
在分析多通道单极子次级源控制系统的基础上,提出一种幅度调节型组合次级声源,这种组合源由两个单极子声源构成,单极子声源的间距远小于声波的波长。文中就组合次级源在自由场中对不同初级声源辐射噪声的控制进行理论分析和实验验证,并与同等条件下的单极子次级源控制系统的降噪性能进行了比较分析。数值计算和实验结果均表明,对于不同的初级声场,在次级通道数相同的情况下,组合次级源控制系统可以得到比单极子次级源控制系统高的降噪量。  相似文献   

14.
Feature selection of noise sources is important for noise sources detection and classification. In this paper, a new rough set based feature selection method has been given. Based on the method, a noise sources automatic classification system (NSACS) has been designed and validated. The key idea of the method is that most effective features can distinguish the most number of samples belonging to different classes of noise sources, if they are used for classification. This new approach has been applied into the system NSACS to select relevant features for artificial datasets and real-world datasets and the results have shown that this approach can correctly select all the relevant features of artificial datasets and at the same time it can drastically reduce the number of features. From the experiments, it can be found that to consider all the five datasets, the number of classification features after selection drops to 35% and the accurate classification rate increases about 14%. For the underwater noise sources dataset the number of features drops to 1/5 and the accurate classification rate increases about 6% after feature selection.  相似文献   

15.
侯比学  陈国夫 《光子学报》1998,27(10):896-900
本文详细分析了超短脉冲激光电子学全息选通透过散射介质成象系统的噪音因素,其噪音来源主要有电子学全息图的记录过程、再现过程以及CCD自身的噪音、系统光学元件产生的噪音等等,提出了相应的噪音处理措施.  相似文献   

16.
本文详细分析了超短脉冲激光电子学全息选通透过散射介质成象系统的噪音因素,其噪音来源主要有电子学全息图的记录过程、再现过程以及CCD自身的噪音、系统光学元件产生的噪音等等,提出了相应的噪音处理措施.  相似文献   

17.
18.
Motor fans used for cooling electric motors have long been recognized as one of the major noise sources. Current paper focuses on design of motor fan for electric motors that are used in submarines for pumping sea water. Noise reduction at source is very important and the critical task, for under water applications. An attempt has been made for reduction of motor fan noise by modification of noise sources. For this purpose computational fluid dynamics and computational aeroacoustics code FLUENT package is used to identify the noise sources and to know the overall sound pressure level of motor fan. From these results it is observed that aerodynamic noise is the dominate fan noise source. Aerodynamic noise of motor fan can be reduced by modifying fan geometry. The aerodynamic noise level of motor fan has been reduced by replacing the straight blades with various digits of NACA (National Advisory Committee for Aeronautics) 65 series airfoil sections. From the numerical results it is observed that the minimum sound pressure level for NACA 65-010 is 65.4 dB(A). These numerical results are compared with measurements in a semi-anechoic chamber. It is found that there is good agreement between numerical and experimental results.  相似文献   

19.
I.IntroductionAcousticshockwavcs(ASW)isanimportantphcnomcnoninnonlinearacoustics.Experimentalrcsultshavcshownthatwhenanaircraftcngincinletopcratesneartheson-iccondition,vcrystrongnoisegcncratedbythcfanscanbcreduccdgreat1yowingtothcformationofASWatthcthroatofthcin1etll].ASWisadiscontinuityofacousticvaria-bles,whichisdifTcrcntfromthcshockwavesoccurringinhighspcedsteadyflowinducts.Theformer'sintensityismuch1cssthanthelattcr's.Furthcrmorc,thepositionandintensityofASWisalwayschangedwithtime.l…  相似文献   

20.
This paper investigates the noise sources in a pneumatic nail gun. The study combines two complementary experimental approaches. The first uses simultaneous data observation, with sound, acceleration and air pressure signals simultaneously recorded in conjunction with a nail gun motion high speed video. This strategy allows the identification of the physical processes involved in the operation of the machine at different time instants, as well as the associated noise generation mechanisms. However, since multiple noise sources radiate at the same time, this observation technique is not sufficient for noise source identification and ranking. Thus, a second approach introduces a selective wrapping procedure, and the strategy assures a reliable classification of the noise sources. The investigation considers the following noise origins: the air exhaust, the machine body and the workpiece/worktable.  相似文献   

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