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Cross-correlation function based multipath mitigation technique for cosine-BOC signals

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Journal of Systems Engineering and Electronics 2013年第5期24卷 742-748页

作者： Huihua Chen Weimin Jia Minli Yao department of Electronic & Information Engineering The Secord Artillery Engineering University

We propose a new multipath mitigation technique based on cross-correlation function for the new cosine phased binary off-set carrier （cosine-BOC） modulated signals, which will most likely be employed in both European Galileo system and Chinese Compass system. This technique is implemented to create an optimum cross-correlation function via designing the modulated symbols of the local signal. And the structure of the code tracking loop for cosine-BOC signals is quite simple including only two real correlators. Results demonstrate that the technique efficiently eliminates the ranging errors in the medium and long multipath regions with respect to the conventional receiver correlation techniques.

关键词： multipath cosine phased binary offset carrier (cosine- BOC) GaJiJeo Compass.

Midterm outcome of stapled transanal rectal resection for obstructed defecation syndrome:A single-institution experience in China

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World Journal of Gastroenterology 2013年第38期19卷 6472-6478页

作者： Bin Zhang Jian-Hua Ding Yu-Juan Zhao Meng Zhang Shu-Hui Yin Ying-Ying Feng Ke Zhao department of Colorectal Surgery the Second Artillery General Hospital department of Laboratory Medicine the Second Artillery General Hospital

AIM:To assess midterm results of stapled transanal rectal resection(STARR)for obstructed defecation syndrome(ODS)and predictive factors for ***:From May 2007 to May 2009,75 female patients underwent STARR and were included in the present *** and postoperative workup consisted of standardized interview and physical examination including proctoscopy,colonoscopy,anorectal manometry,and *** and functional results were assessed by standardized questionnaires for the assessment of constipation constipation scoring system(CSS),Longo’s ODS score,and symptom severity score(SSS),incontinence Wexner incontinence score(WS),quality of life Patient Assessment of Constipation-Quality of Life Questionnaire(PAC-QOL),and patient satisfaction visual analog scale(VAS).Data were collected prospectively at baseline,12 and 30 ***:The median follow-up was 30 mo(range,30-46 mo).Late postoperative complications occurred in 11(14.7%)*** of these patients required procedure-related reintervention(one diverticulectomy and two excision of staple granuloma).Although the recurrence rate was 10.7%,constipation scores(CSS,ODS score and SSS)significantly improved after STARR(P<0.0001).Significant reduction in ODS symptoms was matched by an improvement in the PAC-QOL and VAS(P<0.0001),and the satisfaction index was excellent in 25(33.3%)patients,good in 23(30.7%),fairly good in 14(18.7%),and poor in 13(17.3%).Nevertheless,the WS increased after STARR(P=0.0169).Incontinence was present or deteriorated in 8(10.7%)patients;6(8%)of whom were new *** analysis revealed that the occurrence of fecal incontinence(preoperative,postoperative or new-onset incontinence;P=0.028,0.000,and 0.007,respectively)was associated with the success of the ***:STARR is an acceptable procedure for the surgical correction of ***,its impact on symptomatic recurrence and postoperative incontinence may be problematic.

关键词： Colorectal surgery Constipation Stapled transanal rectal resection

The Application of Adaptive Genetic Reduction Algorithm in Pulse Doppler Radar

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The Application of Adaptive Genetic Reduction Algorithm in P...

Study of Coincidence Doppler Broadening in Carbon Nanotubes

第25届中国控制与决策会议

作者： Xu Guoxin Pan Wei Training department Shenyang artillery Academy Electric Detection department Shenyang artillery Academy

ISBN: (纸本)9781467355339

The adaptive genetic reduction algorithm based on knowledge dependability designed as a general optimization method was applied to the ambiguity resolution of pulse Doppler （PD） radar. The fitness, based on squared error for multi-PRF （pulse repeat frequency） consecutive ordered ranges, was designed. The crossover operator and the conditions of ending in GA were discussed. The relations among the probability of ambiguity resolution of this algorithm, the measurement error and the computational efficiency were analyzed. Simulation results show the GA ambiguity resolution algorithm does better than the sliding window algorithm on the probability of ambiguity resolution.

关键词： adaptive genetic algorithm, rough set, PD radar ambiguity resolution, sliding window

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Plasma Science and Technology 2012年第5期14卷 431-433页

作者：郭卫锋郝颖萍成斌刘建党杜淮江翁惠民叶邦角 department of Modern Physics University of Science and Technology of China department of Physics Artillery Academy of PLA

Coincidence Doppler broadening measurements of positron annihilation for multi- walled carbon nanotubes, double-walled carbon nanotubes, single-walled carbon nanotubes and graphite were performed. The ratio curves of the Doppler broadening for these samples to silicon were obtained. It is shown that there are distinct peaks at the position of 10xl0-arn0c for both carbon nanotubes and graphite, however the amplitudes of the peaks are not the same. We have the opinion that these peaks arise from the annihilation of positron with the 2s and 2p electron of carbon element.

关键词： positron annihilation coincidence Doppler broadening carbon nanotubes

Two-phase flow instability in a parallel multichannel system

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Nuclear Science and Techniques 2009年第2期20卷 111-117页

作者： HOU Suxia department of Physics the Second Artillery Engineering Institute Xi＇ an 710025 China

The two-phase flow instabilities observed in through parallel multichannel can be classified into three types,of which only one is intrinsic to parallel multichannel *** intrinsic instabilities observed in parallel multichannel system have been studied *** stable boundary of the flow in such a parallel-channel system are sought,and the nature of inlet flow oscillation in the unstable region has been examined experimentally under various conditions of inlet velocity,heat flux,liquid temperature,cross section of channel and entrance *** results show that parallel multichannel system possess a characteristic oscillation that is quite independent of the magnitude and duration of the initial disturbance,and the stable boundary is influenced by the characteristic frequency of the system as well as by the exit quality when this is low,and upon raising the exit quality and reducing the characteristic frequency,the system increases its instability,and entrance throttling effectively contributes to stabilization of the system.

关键词：多通道系统不稳定性两相流平行入口速度特征频率入口流量液体温度

Shielding performance of metal fiber composites

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中国有色金属学会会刊：英文版 2004年第Z1期14卷 493-496页

作者： CHEN Gang WU Bin CHEN Ze-fei Military Engineering department Artillery Academy Hefei 230031 China Military Engineering Department Artillery Academy Hefei 230031 China College of Mechanical Engineering South China University of Technology Guangzhou 510640 China

Metal fibers have been applied to construct composites with desirable electromagnetic interference shiel ding effectiveness and mechanical properties. Copper and stainless steel fibers were prepared with micro-saw fiberpulling combined cutting method. The cross section of the fibers is hook-like, which is beneficial to the improvement of bonding strength. Cement-based composites with copper and stainless steel fibers were fabricated and their electromagnetic shielding effectiveness was measured in the frequency range of 1 - 5 GHz. The results show that the electromagnetic interference shielding effectiveness of those composites is enhanced by the addition of metal fibers,which functions mainly due to the absorption. At some frequencies, 20 dB or more difference is obtained between the materials with and without metal fibers.

关键词： metal fiber composites shielding performance

The Application of Adaptive Reduction Genetic Algorithm in Radar Equipment Damage Evaluation Method

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The Application of Adaptive Reduction Genetic Algorithm in R...

Degradation data-driven approach for remaining useful life estimation

第25届中国控制与决策会议

作者： Zhang Yu Pan Wei Training department Shenyang artillery Academy Electric Detection department Shenyang artillery Academy

ISBN: (纸本)9781467355339

The paper proposes a rough set attribute reduction algorithm based on AGA, that in order to achieve effectively at tribute reduction, The core is joined initial population in AGA in order to accelerate capability. According to the dependability of decision attribute to the condition attribute, it can but only obtain the capability of part searching, but also retain the peculiarity of all searching. The adaptive crossover probability and adaptive mutation probability are designed, considering the influence of every generation to algorithm and the effect of different individual fitness in every generation. Experimental results show that the accurate reduction and the average algebraic sum all obtain the preferable values.

关键词： rough sets adaptive reduction genetic algorithm relative reduction crossover probability mutation probability

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Journal of Systems Engineering and Electronics 2013年第1期24卷 173-182页

作者： Zhiliang Fan Guangbin Liu Xiaosheng Si Qi Zhang Qinghua Zhang department of Automation The Second Artillery Engineering University department of Automation Tsinghua University Guangdong University of Petrochemical Technology

Remaining useful life （RUL） estimation is termed as one of the key issues in prognostics and health management （PHM）. To achieve RUL estimation for individual equipment, we present a degradation data-driven RUL estimation approach under the collaboration between Bayesian updating and expectation maximization （EM） algorithm. Firstly, we utilize an exponential-like degradation model to describe equipment degradation process and update stochastic parameters in the model via Bayesian approach. Based on the Bayesian updating results, both probability distribution of the RUL and its point estimation can be derived. Secondly, based on the monitored degradation data to date, we give a parameter estimation approach for non-stochastic parameters in the degradation model and prove that the obtained estimation is unique and optimal in each iteration. Finally, a numerical example and a practical case study for global positioning system （GPS） receiver are provided to show that the presented approach can model degradation process and achieve RUL estimation effectively and generate better results than a previously reported approach in literature.

关键词： reliability degradation remaining useful life (RUL) prognostics global positioning system (GPS).

Comparison of two position sensitive gamma-ray detectors based on continuous YAP and pixellated NaI(TI) for nuclear medical imaging applications

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Chinese Physics C 2008年第11期32卷 934-938页

作者：祝杰马红光马文彦曾晖汪兆民许咨宗 The Second artillery Engineering Institute department of Modern Physics University of Science and Technology of China

Dedicated position sensitive gamma-ray detectors based on position sensitive photomultiplier tubes （PSPMTs） coupled to scintillation crystals, have been used for the construction of compact gamma-ray imaging systems, suitable for nuclear medical imaging applications such as small animal imaging and single organ imaging and scintimammography. In this work, the performance of two gamma-ray detectors： a continuous YAP scintillation crystal coupled to a Harnamastu R2486 PSPMT and a pixellated NaI（TI） scintillation array crystal coupled to the same PSPMT, is compared. The results show that the gamma-ray detector based on a pixellated NaI（TI） scintillation array crystal is a promising candidate for nuclear medical imaging applications, since their performance in terms of position linearity, spatial resolution and effective field of view （FOV） is superior than that of the gamma-ray detector based on a continuous YAP scintillation crystal. However, a better photodetector （Hamamatau H8500 Flat Panel PMT, for example） coupled to the continuous crystal is also likely a good selection for nuclear medicine imaging applications.

关键词： gamma-ray detector PSPMT continuous YAP scintillation crystal NaI(TI) scintillation array crystal