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ACCURACY ANALYSIS OF PASSIVE LOCATION SYSTEM WITH PHASE DIFFERENCE RATE MEASUREMENT 被引量:1
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作者 邓新蒲 姜文利 周一宇 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2000年第4期222-227,共6页
The conventional mono-station passive location techniques of direction finding are low in speed and accuracy, due to the little information available. In this paper, a novel measurement-rate (derivative) of phase diff... The conventional mono-station passive location techniques of direction finding are low in speed and accuracy, due to the little information available. In this paper, a novel measurement-rate (derivative) of phase difference from a two-element antenna array (interferometer) is introduced, accuracy of a passive location system with this measurement and directions of arrival (DOA) is analyzed, and the Cramer-Rao bound of location error of this system for 3D location is examined by simulations. 展开更多
关键词 passive location phase difference rate location accuracy analysis INTERFEROMETER
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Effect of strain rate difference between inside and outside groove in M-K model on prediction of forming limit curve of Ti6Al4V at elevated temperatures 被引量:4
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作者 Xiao-qiang LI Hong-rui DONG +2 位作者 Hai-bo WANG Gui-qiang GUO Dong-sheng LI 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2020年第2期405-416,共12页
The influence of initial groove angle on strain rate inside and outside groove of Ti6Al4V alloy was investigated.Based on the evolution of strain rate inside and outside groove,the effect of strain rate difference on ... The influence of initial groove angle on strain rate inside and outside groove of Ti6Al4V alloy was investigated.Based on the evolution of strain rate inside and outside groove,the effect of strain rate difference on the evolution of normal stress and effective stress inside and outside groove was also analyzed.The results show that when linear loading path changes from uniaxial tension to equi-biaxial tension,the initial groove angle plays a weaker role in the evolution of strain rate in the M-K model.Due to the constraint of force equilibrium between inside and outside groove,the strain rate difference makes the normal stress inside groove firstly decrease and then increase during calculation,which makes the prediction algorithm of forming limit convergent at elevated temperature.The decrease of normal stress inside groove is mainly caused by high temperature softening effect and the rotation of groove,while the increase of normal stress inside groove is mainly due to strain rate hardening effect. 展开更多
关键词 Ti6Al4V alloy strain rate difference forming limit M-K model stress evolution
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Reducing the Internal Difference Error Rate in Hospital Pharmacies:From the Angle of Quality Control Circle 被引量:1
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作者 Wang Shuling Lei Yingzi +2 位作者 Liu Linchuan Wang Ruili He Yalan 《Asian Journal of Social Pharmacy》 2020年第2期73-82,共10页
Objective To improve the management level of pharmacy dispensing center,reduce dispensing errors and promote the safety of drug use.Methods Hospital pharmacies could be managed according to the theory of quality contr... Objective To improve the management level of pharmacy dispensing center,reduce dispensing errors and promote the safety of drug use.Methods Hospital pharmacies could be managed according to the theory of quality control circle(QCC).Based on the ten steps of QCC,the internal difference error rate in pharmacies could be reduced.Results and Conclusion The error rate of pharmacies was reduced from 2.74‰to 0.57‰,and the goal achievement rate was 108.466.Besides,the progress rate reached 84.82%.The abilities of circle members were improved,and the operation of pharmacy was more standardized.The activity of QCC is helpful to reduce the internal difference error rate,improve the operation level of pharmacy and ensure the safety of drug use. 展开更多
关键词 quality control circle(QCC) medical institution internal difference error rate
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Effect of unequal injection rates and different hopping rates on asymmetric exclusion processes with junction 被引量:1
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作者 肖松 蔡九菊 +1 位作者 刘飞 刘明哲 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第9期42-52,共11页
In this paper, the effects of unequal injection rates and different hopping rates on the asymmetric simple exclusion process (ASEP) with a 2-input 1-output junction are studied by using a simple mean-field approach ... In this paper, the effects of unequal injection rates and different hopping rates on the asymmetric simple exclusion process (ASEP) with a 2-input 1-output junction are studied by using a simple mean-field approach and extensive computer simulations. The steady-state particle currents, the density profiles, and the phase diagrams are obtained. It is shown that with unequal injection rates and different hopping rates, the phase diagram structure is qualitatively changed. The theoretical calculations are in good agreement with Monte Carlo simulations. 展开更多
关键词 asymmetric simple exclusion processes mean-field approximation JUNCTION different hopping rates
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Adaptive learning rate GMM for moving object detection in outdoor surveillance for sudden illumination changes 被引量:1
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作者 HOCINE Labidi 曹伟 +2 位作者 丁庸 张笈 罗森林 《Journal of Beijing Institute of Technology》 EI CAS 2016年第1期145-151,共7页
A dynamic learning rate Gaussian mixture model(GMM)algorithm is proposed to deal with the problem of slow adaption of GMM in the case of moving object detection in the outdoor surveillance,especially in the presence... A dynamic learning rate Gaussian mixture model(GMM)algorithm is proposed to deal with the problem of slow adaption of GMM in the case of moving object detection in the outdoor surveillance,especially in the presence of sudden illumination changes.The GMM is mostly used for detecting objects in complex scenes for intelligent monitoring systems.To solve this problem,a mixture Gaussian model has been built for each pixel in the video frame,and according to the scene change from the frame difference,the learning rate of GMM can be dynamically adjusted.The experiments show that the proposed method gives good results with an adaptive GMM learning rate when we compare it with GMM method with a fixed learning rate.The method was tested on a certain dataset,and tests in the case of sudden natural light changes show that our method has a better accuracy and lower false alarm rate. 展开更多
关键词 object detection background modeling Gaussian mixture model(GMM) learning rate frame difference
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Fusion Reaction Rate Coefficient for Different Beam and Target Scenarios
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作者 欧巍 曾宪俊 +1 位作者 邓柏权 苟富均 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第2期43-47,共5页
Fusion power output is proportional not only to the fuel particle number densities participating in reaction but also to the fusion reaction rate coefficient (or reactivity), which is dependent on reactant velocity ... Fusion power output is proportional not only to the fuel particle number densities participating in reaction but also to the fusion reaction rate coefficient (or reactivity), which is dependent on reactant velocity distribution functions. They are usuMly assumed to be dual Maxwellian distribution functions with the same temperature for thermal nuclear fusion circumstances. However, if high power neutral beam injection and minority ion species ICRF plasma heating, or multi-pinched plasma beam head-on collision, in a converging region are required and investigated in future large scale fusion reactors, then the fractions of the injected energetic fast ion tail resulting from ionization or charge exchange will be large enough and their contribution to the non-Maxwellian distribution functions is not negligible, hence to the fusion reaction rate coefficient or calculation of fusion power. In such cases, beam-target, and beam-beam reaction enhancement effect contributions should play very important roles. In this paper, several useful formulae to calculate the fusion reaction rate coefticient for different beam and target combination scenarios are derived in detail 展开更多
关键词 Fusion Reaction rate Coefficient for Different Beam and Target Scenarios exp
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Rate of Phase Difference Change Estimation in Single Airborne Passive Locating System 被引量:5
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作者 王军虎 王永生 +2 位作者 郭涛 王洪浩 王强 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2009年第2期184-190,共7页
As an important parameter in the single airborne passive locating system, the rate of phase difference change contains range information of the radio emitter. Taking single carrier sine pulse signals as an example, th... As an important parameter in the single airborne passive locating system, the rate of phase difference change contains range information of the radio emitter. Taking single carrier sine pulse signals as an example, this article illustrates the principle of passive location through measurement of rates of phase difference change and analyzes the structure of measurement errors. On the basis of the Cramér-Rao lower bound (CRLB), an algorithm associated with time-chips is proposed to determine the rates of pha... 展开更多
关键词 LOCATION rate of phase difference change Cramér-Rao lower bound phase discrimination multi-chip processing
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A specific objective supplemental factor in evaluating acute mountain sickness: ΔHR in combination with SaO_2 被引量:7
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作者 Ming Li Ji-Hang Zhang +8 位作者 Guo-Xi Zhao Shi-Zhu Bian Xu-Bin Gao Xi Liu Jie Yu Jun-Qing Dong Guo-Zhu Chen Hong Wang Lan Huang 《Military Medical Research》 SCIE CAS 2015年第3期139-144,共6页
Background: So far, there have been no measurements confirmed useful in diagnosing acute mountain sickness(AMS). The aim of this study was to determine the role of heart rate(HR) difference(ΔHR) and oxygen saturation... Background: So far, there have been no measurements confirmed useful in diagnosing acute mountain sickness(AMS). The aim of this study was to determine the role of heart rate(HR) difference(ΔHR) and oxygen saturation(Sa O2) as objective risk factors in aiding the diagnosis of AMS.Methods: A total of 1,019 participants were assigned to either the acute exposure group(AEG): from 500 m to 3,700 m by flight within 2.5 hours(n=752); or the pre-acclimatization group(PAG): ascended to 4,400 m from 3,650 m within three hours by car after adapting 33 days at 3,650m(n=267). The questionnaires or measurements of resting Sa O2 and HR were completed between 18 and 24 hours before departure and after arrival.Results: Incidence of AMS was 61.3%(461) in AEG, with 46.1%(347) mild cases and 15.2%(114) severe cases. In PAG, the incidence was 38.9%(104), with 30.7%(82) mild cases and 8.2%(22) severe cases. The AMS subjects showed a significant increase in HR and a decrease in Sa O2 levels compared with the non-AMS subjects in both groups. ΔHR and post-exposure Sa O2 were significantly correlated with the Lake Louise Score(LLS) in both groups. Stepwise logistic regression analysis revealed the ΔHR >25 and Sa O2 <88% in AEG as well as ΔHR >15 and Sa O2 <86% in PAG to be independent risk factors of AMS. Combining these two measurements could specifically indicate participants with AMS, which showed a positive predictive value of 89% and specificity of 97% in AEG as well as 85% and 98% in PAG.Conclusion:ΔHR or Sa O2, as objective measurements, correlate with AMS. Combination of these two measurements may be useful as an additional specific and objective factor to further confirm the diagnosis of AMS. 展开更多
关键词 Acute mountain sickness Oxygen saturation Heart rate difference
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Midinfrared optical frequency comb based on difference frequency generation using high repetition rate Er-doped fiber laser with single wall carbon nanotube film 被引量:3
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作者 M.Tsuzuki L.Jin +9 位作者 M.Yamanaka V.Sonnenchein H.Tomita A.Sato T.Ohara Y.Sakakibara E.Omoda H.Kataura T.Iguchi N.Nishizawa 《Photonics Research》 SCIE EI 2016年第6期313-317,共5页
We demonstrated stable midinfrared(MIR) optical frequency comb at the 3.0 μm region with difference frequency generation pumped by a high power, Er-doped, ultrashort pulse fiber laser system. A soliton mode-locked161... We demonstrated stable midinfrared(MIR) optical frequency comb at the 3.0 μm region with difference frequency generation pumped by a high power, Er-doped, ultrashort pulse fiber laser system. A soliton mode-locked161 MHz high repetition rate fiber laser using a single wall carbon nanotube was fabricated. The output pulse was amplified in an Er-doped single mode fiber amplifier, and a 1.1–2.2 μm wideband supercontinuum(SC) with an average power of 205 m W was generated in highly nonlinear fiber. The spectrogram of the generated SC was examined both experimentally and numerically. The generated SC was focused into a nonlinear crystal, and stable generation of MIR comb around the 3 μm wavelength region was realized. 展开更多
关键词 high Midinfrared optical frequency comb based on difference frequency generation using high repetition rate Er-doped fiber laser with single wall carbon nanotube film MIR SWNT PCF rate mode DSF EDF length SC DFG
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Performance Analysis of a Discrete-Time Queue with Working Breakdowns and Searching for the Optimum Service Rate in Working Breakdown Period 被引量:1
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作者 Shaojun LAN Yinghui TANG 《Journal of Systems Science and Information》 CSCD 2017年第2期176-192,共17页
This paper deals with a discrete-time Geo/Geo/1 queueing system with working breakdowns in which customers arrive at the system in variable input rates according to the states of the server. The server may be subject ... This paper deals with a discrete-time Geo/Geo/1 queueing system with working breakdowns in which customers arrive at the system in variable input rates according to the states of the server. The server may be subject to breakdowns at random when it is in operation. As soon as the server fails, a repair process immediately begins. During the repair period, the defective server still provides service for the waiting customers at a lower service rate rather than completely stopping service.We analyze the stability condition for the considered system. Using the probability generating function technique, we obtain the probability generating function of the steady-state queue size distribution.Also, various important performance measures are derived explicitly. Furthermore, some numerical results are provided to carry out the sensitivity analysis so as to illustrate the effect of different parameters on the system performance measures. Finally, an operating cost function is formulated to model a computer system and the parabolic method is employed to numerically find the optimum service rate in working breakdown period. 展开更多
关键词 discrete-time queue working breakdowns different arrival rates performance measures optimum service rate
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Asymmetric Coupling in Two-Lane Asymmetric Simple Exclusion Processes with Unequal Injection Rates: Effect of Different Hoping Rates
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作者 肖松 陈晓瑜 刘艳娜 《Communications in Theoretical Physics》 SCIE CAS CSCD 2015年第5期581-587,共7页
This paper investigates the effect of both unequal injection rates and different hopping rates on two-lane asymmetric simple exclusion processes(ASEPs) with asymmetric coupling. When the hopping rates of both lanes ar... This paper investigates the effect of both unequal injection rates and different hopping rates on two-lane asymmetric simple exclusion processes(ASEPs) with asymmetric coupling. When the hopping rates of both lanes are different, the system includes six steady phases, however, when the hopping rates of both lanes are same, the seventh phase(MC, MC) will exist in the system. Interestingly, with different hopping rates of both lanes, the densities of the system cannot be influenced by the non-zero vertical transition rate. Our theoretical arguments are in well agreement with extensively performed Monte Carlo simulations. 展开更多
关键词 asymmetric simple exclusion processes unequal injection rates different hoping rates mean fieldapproximation Monte Carlo simulations
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PREDECESSOR-SET TECHNIQUE FOR RELIABILITY EVALUATION OF A STOCHASTIC MANUFACTURING SYSTEM 被引量:1
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作者 Yi-Kuei Lin Ping-Chen Chang 《Journal of Systems Science and Systems Engineering》 SCIE EI CSCD 2015年第2期190-210,共21页
This paper studies the reliability evaluation of a stochastic manufacturing system with multiple production lines in parallel. Multiple repairs and different failure rates, never simultaneously addressed in earlier wo... This paper studies the reliability evaluation of a stochastic manufacturing system with multiple production lines in parallel. Multiple repairs and different failure rates, never simultaneously addressed in earlier works, are taken into account. First, a revised graphical methodology integrating transformation and decomposition is utilized to construct the stochastic manufacturing system as a multi-state manufacturing network (MSMN). In particular, a "predecessor-set" technique is proposed to deal with multiple repairs. An algorithm is proposed to generate the lowest capacity vectors (LCVs) that stations should provide to satisfy the workloads. Subsequently, the system reliability of the MSMN, which is defined as the probability of demand satisfaction, is calculated in terms of the LCVs. A real case of a printed circuit board manufacturing system is utilized to demonstrate how the system reliability can be evaluated. A further decision making issue is addressed based on the derived system reliability. 展开更多
关键词 Multi-state manufacturing network (MSMN) predecessor-set lowest capacity vector(LCV) different failure rates multiple repairs system reliability
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Probing and modulating the interactions of the DNAzyme with DNA-functionalized nanoparticles 被引量:1
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作者 Yuqiang Hu Zhen Zhang +3 位作者 Wei Zhang Minghao Hu Xianjin Xiao Tongbo Wu 《Chinese Chemical Letters》 SCIE CAS CSCD 2022年第6期3026-3030,共5页
DNA-functionalized gold nanoparticles are one of the most versatile bionanomaterials for biomedical and clinical diagnosis. Herein, we discovered that the performance of DNAzyme cleaving the substrate is highly relate... DNA-functionalized gold nanoparticles are one of the most versatile bionanomaterials for biomedical and clinical diagnosis. Herein, we discovered that the performance of DNAzyme cleaving the substrate is highly related to its length. This intriguing phenomenon only appears at the interfaces of DNAfunctionalized gold nanoparticles. We systematically investigated the causes of this phenomenon. We conjectured that the DNAzyme with extended nucleotides that do not match its substrate strand is vulnerable to non-specific adsorption, electrostatic repulsion, and steric hindrance. Based on our improved understanding of this phenomenon, we have successfully developed a highly sensitive and specific amplifiable biosensor to detect human apurinic/apyrimidinic endonuclease 1. 展开更多
关键词 Gold nanoparticles DNAZYME Interface interaction rate difference Human apurinic/apyrimidinic endonuclease 1
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