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971.
旋叶式汽车空调压缩机的噪声源识别   总被引:2,自引:0,他引:2  
运用分别运行法、频谱法和声强法分析了JSS-96系列旋叶式汽车空调压缩机噪声的产生机理,指出该型号压缩机的噪声源主要是由电机噪声和排气口的气体压力脉动引起的周期性脉动噪声以及进气噪声,其中电机噪声和进排气脉动噪声对整个压缩机的噪声贡献最大,为进一步控制压缩机的噪声提供了依据.  相似文献   
972.
Sepsis is a common and serious medical condition caused by hemorrhage, trauma, or abdominal surgery. Despite new understanding and much progress in therapies that specifically interfere with an interesting target, sepsis remains the leading causes of death in critically ill patients. Various therapies have been studied, but the majority of these treatments fail in clinical trials. It is clear that all septic patients exhibit coagulation abnormalities. These abnormalities range from subtle to marked activation of coagulation system, and finally to fulminant DIC. Studies confirmed that carbon monoxide has important cytoprotective function and anti-inflammatory properties. Until now, the question of whether CO plays a critical role in improving the coagulation system and then decreasing mortality during sepsis has not yet been definitely answered. Attempts to confirm this strategy may lead to new directions in the study of treatment of sepsis and the development of a novel agent for this disorder. Received 13 August 2008; received after revision 29 October 2008; accepted 17 November 2008  相似文献   
973.
相干源诱偏下比相被动雷达导引头测角性能分析   总被引:2,自引:0,他引:2  
从比相单脉冲测向体制出发,推导出比相体制PRS跟踪相干两点源的数学模型,对两点源诱偏下被动雷达导引头的测角性能进行了分析,指出比相体制导引头无法分辨雷达和相干源诱饵,PRS将跟踪雷达和诱饵的合成相位中心,跟踪角度不固定且不断变化。仿真结果和实测数据均验证了结论的正确性。  相似文献   
974.
为评估室内LED光源潜在的光生物安全风险,搭建了光生物安全测试系统平台.在该系统平台上对常用的几款室内LED光源进行了较全面的光生物安全测试.并对照标准GB /T 20145—2006《光源和光源系统的光生物安全》的要求,对实验结果作了较为详细的分析,对该光源的危险类别做了判定划分.该报告分析对搭建室内LED产品的光生物安全性测试系统以及研究其测试方法均具有一定的参考意义.  相似文献   
975.
Flexible strain sensors have received increasing attention with the development of wearable electronic devices. However, integrating wide strain detection range, high sensitivity while maintaining relatively wide linear response range for such sensor system still remain a challenge. A fabric based flexible sensor (S-CNT/PDMS-F) was designed and fabricated, and the sensor can simultaneously achieve high sensitivity, wide linear response and strain detection range by combining self-segregated carbon nanotube (CNT)/polydimethylsiloxane (PDMS) composites and elastic medical bandage. It has been observed that this new sensor system can achieve a high sensitivity with a gauge factor of 615, a large linear responsive range of 0–100% strain (R2 ?= ?0.993) and a wide strain detection range of ~ 200%, which is superior to almost all the reported CNT/PDMS flexible strain sensors. Compared to the similar fabric based strain sensor system deploying non self-segregated structure (C-CNT/PDMS-F), our S-CNT/PDMS-F demonstrates higher electrical conductivity and lower electrical percolation threshold and response time of 55 ?ms, as well as more stable and repeatable performance under cyclic loading conditions. The capability of the sensors in monitoring physiological activities and weight distribution has also been demonstrated.  相似文献   
976.
Through establishing Carbon Trading Platform (Carbon Trading Alliance) in the Carbon Trading Market, each participant can benefit more from the cooperation. But, the distributing mechanism of earnings of the market nowadays has a great influence on the development of Carbon Trading Platform. Based on that, the paper firstly utilize the traditional shapley value method to distribute the cooperative earnings of the Carbon Trading Market. Then, the risking factors taken by alliance members were brought in, and the weights of risks obtained trough the method of AHP, and risking coefficient was received. At last the existing results were corrected and the final distribution results were obtained. Finally, an example is used to verify the theory above. The research results show that the allocation system, taking risking factors into account, can improve the members'' enthusiasm to participate in the Carbon Trading Platform and promote the development and improvement of the Carbon Trading Platform and the market. Therefore, the results of this paper can provide a reference for policymakers of Carbon Trading Market.  相似文献   
977.
郑天  李峰  贺乃宝  顾亚 《系统仿真学报》2022,34(11):2377-2385
针对非线性系统中噪声的干扰,研究了一类神经模糊Hammerstein输出误差非线性系统的建模和辨识方法,利用组合式信号源实现静态非线性模块和动态线性模块参数辨识的分离,推导了相关性分析法和辅助模型递推最小二乘辨识方法估计动态线性模块和非线性模块的参数,有效抑制系统输出噪声的干扰。仿真结果表明:与最小二乘算法、多项式模型以及多信息方法相比,提出的方法具有参数估计收敛速度快,辨识精度高,建模误差小等优势,验证了所提学习算法的有效性。  相似文献   
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