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胶合板木段进给、定心方法和设备:US6176282
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作者 夕波 《国际木业》 2002年第12期38-38,共1页
关键词 胶合板 木段进给 定心方法 US6176282 旋切设备 单板 专利
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快速定心的设想
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作者 杨向明 《铁道机车车辆工人》 2002年第2期32-32,共1页
关键词 矩形工件 快速定心方法 加工 中心探测器 矩形杆 中心线位置
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一种30倍连续变焦电视光学系统装调技术研究 被引量:2
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作者 张向明 王中强 +5 位作者 昌明 李玉喜 姜峰 王章利 马力 赵玮 《光电工程》 CAS CSCD 北大核心 2019年第4期64-70,共7页
针对30倍连续变焦电视公差灵敏度高,装调难度大的问题,运用光学仿真方法分析各分离透镜偏心对光学系统MTF的影响。结果显示,前组镜中心偏差对系统像质影响敏感,会产生非对称像差。本文优选光机界面的结构形式,使透镜下表面自动定心,微... 针对30倍连续变焦电视公差灵敏度高,装调难度大的问题,运用光学仿真方法分析各分离透镜偏心对光学系统MTF的影响。结果显示,前组镜中心偏差对系统像质影响敏感,会产生非对称像差。本文优选光机界面的结构形式,使透镜下表面自动定心,微调上表面将偏心控制在公差范围内。变倍组、补偿组作为运动组件,在变焦过程中光轴共轴性也是影响系统像质的关键因素。本文采用机械定心工装使运动组件的中心轴线与导杆轴线平行,再以前组镜透射光轴为基准,校正所有光学部件光轴与之共轴。光学系统经过精密装调,小视场像质分辨率达到2.43″,接近衍射分辨率极限。 展开更多
关键词 连续变焦 光机界面 定心方法
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Non-iterative image feature matching algorithm based on reference point correspondences 被引量:1
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作者 张维中 张丽艳 +2 位作者 王小平 丁志安 周玲 《Journal of Southeast University(English Edition)》 EI CAS 2007年第2期190-195,共6页
Based on the coded and non-coded targets, the targets are extracted from the images according to their size, shape and intensity etc., and thus an improved method to identify the unique identity(D) of every coded ta... Based on the coded and non-coded targets, the targets are extracted from the images according to their size, shape and intensity etc., and thus an improved method to identify the unique identity(D) of every coded target is put forward and the non-coded and coded targets are classified. Moreover, the gray scale centroid algorithm is applied to obtain the subpixel location of both uncoded and coded targets. The initial matching of the uncoded target correspondences between an image pair is established according to similarity and compatibility, which are based on the ID correspondences of the coded targets. The outliers in the initial matching of the uncoded target are eliminated according to three rules to finally obtain the uncoded target correspondences. Practical examples show that the algorithm is rapid, robust and is of high precision and matching ratio. 展开更多
关键词 reference points detection coded and non-coded target SUBPIXEL gray scale centroid point correspondence
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Factors Influencing on Drinking Water Source Selection in Rural Areas of the Bengal Region
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作者 Maiko Sakamoto 《Journal of Environmental Science and Engineering(A)》 2013年第11期664-676,共13页
The arsenic contamination of underground water is a serious problem in rural areas of the Bengal region, where the water pipeline supply is not equipped. Those, who suffer from the contamination are mainly in the poor... The arsenic contamination of underground water is a serious problem in rural areas of the Bengal region, where the water pipeline supply is not equipped. Those, who suffer from the contamination are mainly in the poorest sector. In the region, the selection of drinking water sources is done by women. The local traditional custom of Parda may restrict women's behavior. In this paper, a quantitative way of evaluating women's psychological stress is proposed, and mechanisms of women's water selection are analyzed using behavioral model. Ultimately, the more acceptable ways of installing water facilities to local people in each village are discussed. 展开更多
关键词 South Asia arsenic contamination drinking water GENDER space syntax.
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Managing and Measuring Business Networks in Russia
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作者 Seppo E. Niittymaki Lauri J. Tenhunen 《Chinese Business Review》 2012年第5期483-490,共8页
The research topic of this article "Managing and measuring business networks in Russia" has been under consideration in three successive research projects oriented to Russian business to business (B2B) networks. T... The research topic of this article "Managing and measuring business networks in Russia" has been under consideration in three successive research projects oriented to Russian business to business (B2B) networks. The projects have been accomplished by HAMK, VTT Technical Research Centre of Finland, and Tampere University of Technology (TUT). Russian experts from The Higher School of Economics in Moscow and the Graduate School of Management in St. Petersburg were involved in these projects. We asked how managing and measuring B2B networks should be developed, when a company becomes established to Russian market. Both qualitative and quantitative analytical methods were used. Results concerning performance measurement presented in this article are based on data which was collected using survey and a questionnaire. Methodical triangulation was carried out as both research instruments produced 17 full answers for questions concerning performance measurement. Wider results are based on about 200 face-to-face interviews and answers for questionnaires. Results indicate that in Russia the management and leadership models as well as the company performance measurement should be adjusted to Russian traditions. Networked companies have difficulties in applying matrix type organizations in Russia, as management practices are based traditionally on authoritarian leadership. However, clear and specific targets should be set for projects and strategic business areas. Targets and bonuses should be agreed on with managers and staff throughout the company and the business network. Personal networks, within project stake- holders, have more emphasis in Russia than in Finland, because personal relations to authorities', and organizations are needed at every stage of the project. Therefore, managing SMEs working in B2B networks is challenging in Russia. In this article, a method for setting and implementing strategic targets for a business networked company is presented. Understanding networked performance measurement indicators will enable successful business for all networked partners in the long tenn. 展开更多
关键词 MANAGING measuring performance business networks RUSSIA
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Monte-Carlo based cascade control approach with focus on real overactuated space systems
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作者 M.Shahi A.H.Mazinan 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第12期3171-3182,共12页
The present research relies on a cascade control approach through the Monte-Carlo based method in the presence of uncertainties to evaluate the performance of the real overactuated space systems.A number of potential ... The present research relies on a cascade control approach through the Monte-Carlo based method in the presence of uncertainties to evaluate the performance of the real overactuated space systems.A number of potential investigations in this area are first considered to prepare an idea with respect to state-of-the-art.The insight proposed here is organized to present attitude cascade control approach including the low thrust in connection with the high thrust to be implemented,while the aforementioned Monte-Carlo based method is carried out to guarantee the approach performance.It is noted that the investigated outcomes are efficient to handle a class of space systems presented via the center of mass and the moments of inertial.And also a number of profiles for the thrust vector and the misalignments as the disturbances all vary in its span of nominal variations.The acquired results are finally analyzed in line with some well-known benchmarks to verify the approach efficiency.The key core of finding in the research is to propose a novel 3-axis control approach to deal with all the mentioned uncertainties of space systems under control,in a synchronous manner,as long as the appropriate models in the low-high thrusts are realized. 展开更多
关键词 Monte-Carlo based method cascade control approach overactuated space systems low-high thrusts models
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Effect of pulsatile perfusion during cardiopulmonary bypass in terms of radial artery sphygmogram 被引量:2
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作者 Zhifeng Zhang Jiatuo Xu +15 位作者 Enyuan Zhu Qi Zhang Lu Yu Yongbing Qiu Jianguo Tang Zhaofu Fei Xin Li Liping Tu Chouping Han Ying Liu Zhen Guo Changle Zhou Meiyu Shi Yingxin Qian Yimin Bao Xinming Ji 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2014年第6期673-677,共5页
OBJECTIVE: To investigate a quantitative method for using radial artery pulse waveforms to assess the effect of pulsatile flow during cardiopulmonary bypass(CPB).METHODS: A total of 34 adults with heart disease who un... OBJECTIVE: To investigate a quantitative method for using radial artery pulse waveforms to assess the effect of pulsatile flow during cardiopulmonary bypass(CPB).METHODS: A total of 34 adults with heart disease who underwent open-heart surgery between April2010 and January 2011 were randomized into a pulsatile perfusion group(n=17) and a non-pulsatile perfusion group(n=17). Radial arterial pulse waveforms of pulsatile and non-pulsatile perfusion patients were observed and compared before and during CPB.RESULTS: No pulse waveform could be detected at patients' radial artery in both groups when the aorta was cross-clamped. Pulse waveforms could be detected at pulsatile perfusion patients' radial artery, but could not be detected at non-pulsatile perfusion patients' radial artery during CPB. Additionally, patients' pulse waveforms during pulsatile perfusion were lower than those before the operation.CONCLUSION: Our findings indicate that radial artery sphygmogram can be used as a valid indicator to evaluate the effectiveness of pulsatile perfusion during CPB. 展开更多
关键词 Cardiopulmonary bypass Pulsatileflow Radial artery Pulse waveforms SPHYGMOGRAM
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Determination of regional earthquake source parameters in wavelet domain 被引量:3
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作者 HAO JinLai YAO ZhenXing 《Science China Earth Sciences》 SCIE EI CAS 2012年第2期296-305,共10页
Investigating source parameters of small and moderate earthquakes plays an important role in seismology research. For small and moderate earthquakes, the mechanisms are usually obtained by first motion of P-Wave, surf... Investigating source parameters of small and moderate earthquakes plays an important role in seismology research. For small and moderate earthquakes, the mechanisms are usually obtained by first motion of P-Wave, surface wave spectra method in frequency-domain or the waveform inversion in time-domain, based on the regional waveform records. We applied the wavelet domain inversion method to determine mechanism of regional earthquake. Using the wavelet coefficients of different scales can give more information to constrain the inversion. We determined the mechanisms of three earthquakes occurred in California, the United States. They are consistent with the previous results (Harvard Centroid Moment Tensor and United States Geological Service). This proves that the wavelet domain inversion method is an efficient method to determine the source parameters of small and moderate earthquakes, especially the strong aftershocks after a large, disastrous earthquake. 展开更多
关键词 wavelet domain inversion method regional earthquake focal mechanism
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