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Protective effect of Radix Astragali injection on immune organs of rats with obstructive jaundice and its mechanism 被引量:24
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作者 Rui-Ping Zhang Xi-Ping Zhang +4 位作者 Yue-Fang Ruan Shu-Yun Ye Hong-Chan Zhao Qi-Hui Cheng Di-Jiong Wu 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第23期2862-2869,共8页
AIM: To observe the protective effect of Radix Astragali injection on immune organs (lymph nodes, spleen and thymus) of rats with obstructive jaundice (OJ) and its mechanism. METHODS: SD rats were randomly divided int... AIM: To observe the protective effect of Radix Astragali injection on immune organs (lymph nodes, spleen and thymus) of rats with obstructive jaundice (OJ) and its mechanism. METHODS: SD rats were randomly divided into sham-operation group, model control group and Radix Astragali treatment group. On days 7, 14, 21 and 28 after operation, mortality rate of rats, pathological changes in immune organs, expression levels of Bax and nuclear factor (NF)-κB p65 proteins, apoptosis indexes and serum tumor necrosis factor (TNF)-α level in spleen and thymus were observed, respectively.RESULTS: Compared to model control group, the number of dead OJ rats in Radix Astragali treatment group decreased (P > 0.05). The TNF-α level (27.62 ± 12.61 vs 29.55 ± 18.02, 24.61 ± 9.09 vs 31.52 ± 10.95) on days 7 and 21, the pathological severity score for spleen [0.0 (0.0) vs 0.0 (2.0) on days 7 and 14 and for lymph nodes [0.0 (1.0) vs 1.0 (2.0), 1.0 (0.0) vs 2.0 (1.0)] on days 21 and 28, the product staining intensity and positive rate of Bax protein in spleen [0.0 (0.0) vs 1.0 (2.0), 0.0 (1.0) vs 2.0 (1.5) and thymus [0.0 (0.0) vs 1.0 (2.0), 0.0 (1.0) vs 2.0 (1.5)] on days 14 and 28, the apoptotic indexes [0.0 (0.0) vs 0.0 (0.01)] in spleen and thymus [0.0 (0.0) vs 0.0 (0.01) on days 14 and 21 were significantly lower in Radix Astragali treatment group than in model control group (P < 0.05). CONCLUSION: Radix Astragali has protective effects on immune organs of OJ rats by relieving the pathological changes in immune organs, reducing TNF-α level and inhibiting Bax expression and apoptosis in spleen and thymus. 展开更多
关键词 免疫器官 保护作用 注射液 机制 大鼠 黄疸 阻性
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Design for Quick Evaluating Platform of Servo System Status
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作者 沈怀荣 牛亚峰 《Defence Technology(防务技术)》 SCIE EI CAS 2006年第3期198-201,共4页
关键词 伺服系统 故障诊断 框架设计 武器
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NUMERICAL ANALYSIS OF STRIKE OF PISTON TO CYLINDER UNDER SUPERCHARGE CO NDITIONS
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作者 余志壮 宋正华 +1 位作者 董光能 谢友柏 《Journal of Pharmaceutical Analysis》 SCIE CAS 2004年第2期106-109,共4页
Objective To investigate th e changes to the strike extent of piston to cylinder after engine supercharge de sign. Methods The lubrication model between the skirt of piston and liner is established by means of piston ... Objective To investigate th e changes to the strike extent of piston to cylinder after engine supercharge de sign. Methods The lubrication model between the skirt of piston and liner is established by means of piston dynamics, combined with the hydrody namic lubrication equation. Optimized numerical analysis method is employed in s olving the dynamics and lubrication equations. The analyses about piston strike under two combustion gas pressures are performed. Results The p eak values of maximum eccentricity under supercharge condition are much greater than under non-supercharge condition, which means a stronger impulsion of pisto n to cylinder wall and a greater possibility of scuffing. The horizontal velocit ies of piston in supercharge condition are larger, which illuminate the more uns table motion state. Conclusion The analysis gives a new conclus ion. Combustion gas pressure plays an important role in the piston strike motion . Influences of supercharge should be taken into account so that the traditional product test items can be improved. 展开更多
关键词 PISTON supercharge STRIKE
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Design of a Modified Tracking Differentiator
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作者 Zhigao Liu Yaguang Jiang 《World Journal of Engineering and Technology》 2017年第4期668-674,共7页
A modified tracking differentiator is proposed. Firstly, a nonlinear odd exponent continuous function is adopted which is only stable at one equilibrium point and proved the global asymptotic stability of the modified... A modified tracking differentiator is proposed. Firstly, a nonlinear odd exponent continuous function is adopted which is only stable at one equilibrium point and proved the global asymptotic stability of the modified tracking differentiator by select a Lyapunov function. Through combining of the nonlinear and linear function properly, it can be sure that the state converges to the equilibrium point with high speed automatically no matter that the state was far away from the equilibrium point or near to it, and it can prevent the chattering.?Simulation results show that the modified tracking differentiator tracking results?are?superior to the classical nonlinear tracking differentiator, and the response?of state variables tracking differentiator estimated?is?almost coincide with the real state of the variables of the given system. 展开更多
关键词 TRACKING DIFFERENTIATOR LYAPUNOV FUNCTION Nonlinear SWITCH FUNCTION CHATTERING
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软件工程在导弹攻防作战仿真系统中的应用 被引量:1
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作者 管清波 罗小明 +1 位作者 ZHANG Rong 张荣 《装备指挥技术学院学报》 2001年第1期64-68,共5页
针对作战仿真系统开发过程中所面临的困难,提出了解决此类问题的软件工程方法。应用软件工程方法对军事卫星信息支援下导弹攻防作战仿真系统进行了科学的管理和开发。
关键词 软件工程 卫星应用 作战仿真 导弹攻防
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Monaural speech enhancement using U-net fused with multi-head self-attention
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作者 FAN Junyi YANG Jibin +1 位作者 ZHANG Xiongwei ZHENG Changyan 《Chinese Journal of Acoustics》 CSCD 2023年第1期98-118,共21页
Under low signal-to-noise ratio(SNR)and burst noise conditions,the speech enhancement effect of existing deep learning network models is not satisfactory.In contrast,humans can exploit the long-term correlation of spe... Under low signal-to-noise ratio(SNR)and burst noise conditions,the speech enhancement effect of existing deep learning network models is not satisfactory.In contrast,humans can exploit the long-term correlation of speech to form an integrated perception of different speech signals.Thus,describing the long-term dependencies of speech can help improve the enhancement performance under low SNR and burst noise conditions.Inspired by this feature,a time domain end-to-end monaural speech enhancement model TU-net that fuses the multi-head self-attention mechanism and U-net deep network is proposed.The TU-net model adopts the codec layer structure of U-net to achieve multi-scale feature fusion.It introduces the dual-path Transformer module using the multi-head self-attention mechanism to calculate the speech mask and better model long-term correlation.The TU-net model is trained with a weighted sum loss function in the time,time-frequency,and perceptual domains.Simulation experiments are carried out and the results show that with maintaining relatively fewer network model parameters,TU-net outperforms other similar monaural enhancement network models in several evaluation metrics such as perceptual evaluation of speech quality(PESQ),short-time objective intelligibility(STOI)and SNR gain under low SNR and burst noise conditions. 展开更多
关键词 network SPEECH noise
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3-D flame temperature field reconstruction with multiobjective neural network 被引量:2
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作者 万雄 高益庆 汪元美 《Chinese Optics Letters》 SCIE EI CAS CSCD 2003年第2期78-81,共4页
A novel 3-D temperature field reconstruction method is proposed in this paper, which is based on multi-wavelength thermometry and Hopfield neural network computed tomography. A mathematical modelof multi-wavelength th... A novel 3-D temperature field reconstruction method is proposed in this paper, which is based on multi-wavelength thermometry and Hopfield neural network computed tomography. A mathematical modelof multi-wavelength thermometry is founded, and a neural network algorithm based on multiobjectiveoptimization is developed. Through computer simulation and comparison with the algebraic reconstructiontechnique (ART) and the filter back-projection algorithm (FBP), the reconstruction result of the newmethod is discussed in detail. The study shows that the new method always gives the best reconstructionresults. At last, temperature distribution of a section of four peaks candle flame is reconstructed with thisnovel method. 展开更多
关键词 火焰 温度场 辐射温度计
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Human Reliability Analysis Method on Armored Vehicle System Considering Error Correction 被引量:1
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作者 伊枭剑 董海平 +2 位作者 董笑 姜基平 张忠 《Journal of Shanghai Jiaotong university(Science)》 EI 2016年第4期472-477,共6页
Human reliability analysis(HRA) is an expansion of man-machine engineering. It is also a new multidisciplinary based on behavioral science, cognitive science, information processing, system analysis and probability st... Human reliability analysis(HRA) is an expansion of man-machine engineering. It is also a new multidisciplinary based on behavioral science, cognitive science, information processing, system analysis and probability statistics in order to analyze, predict, reduce and prevent human errors. Firstly, the quantitative analysis model of HRA is proposed based on Markov process theory by using human error probability(HEP) and error correction cycle(ECC) as parameters. And human reliability evaluation criterion is built. Then, the HRA process considering error correction is proposed based on cognitive reliability and error analysis method(CREAM). Finally, according to the characteristics of armored vehicle system, common performance condition(CPC) in CREAM is improved.A reliability impact index is characterized by the overall contexts of tasks. Human reliability evaluation criterion of armored vehicle system is formulated. And the result of HRA is obtained based on the method presented in this paper. In addition, the relative weights are estimated by combining scale of 10/10—18/2 and analytical hierarchy process(AHP), and the triangular fuzzy number considering confidence factor and optimism index is adopted in order to reduce the subjectivity. The analysis results show that the method presented in this paper is reasonable and feasible. Meantime, the method can provide guidance for human reliability analysis of other weapon systems. 展开更多
关键词 可靠性分析方法 车辆系统 装甲 误差修正 人的可靠性分析 层次分析法 马尔可夫过程 定量分析模型
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