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Three-dimensional coordinates test method with uncertain projectile proximity explosion position based on dynamic seven photoelectric detection screen

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Defence Technology（防务技术） 2022年第9期18卷 1643-1652页

作者： Han-shan Li xiao-qian zhang School of Electronic and Information Engineering Xi'an Technological UniversityXi'an710021China

To objectively obtain the three-dimensional coordinates of the projectile fuze proximity explosion when projectile intersects the head of missile target, we propose a dynamic seven photoelectric detection screen test method, which is made up of six plane detection screens and a flash photoelectric dynamic detection screen. The three-dimensional coordinates calculation model of the projectile proximity explosion position based on seven plane detection screens with dynamic characteristics is *** to the relation of the dynamic seven photoelectric detection screen planes and the time values,the analytical function of the projectile proximity explosion position parameters under non-linear motion is derived. The projectile signal filtering method based on discrete wavelet transform is explored in this work. Additionally, the projectile signal recognition algorithm using an improved particle swarm is proposed. Based on the characteristics of the time duration and the signal peak error for the projectile passing through the detection screen, the signals attribution of the same projectile passing through six detection screens are analyzed for obtaining precise time values of the same projectile passing through the detection screens. On the basis of the projectile fuze proximity explosion test, the linear motion model and the proposed non-linear motion model are used to calculate and compare the same group of projectiles proximity explosion position parameters. The comparison of test results verifies that the proposed test method and calculation model in this work accurately obtain the actual projectile proximity explosion position parameters.

关键词： Dynamic multi-screen array plane Flash photoelectric detection target Projectile signal processing Particle swarm Proximity explosion fuze Three-dimensional coordinate

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Flight parameter calculation method of multi-projectiles using temporal and spatial information constraint

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Defence Technology（防务技术） 2023年第1期19卷 63-75页

作者： Han-shan Li xiao-qian zhang School of Electronic and Information Engineering Xi'an Technological UniversityXi'an710021China

The dynamic parameters of multiple projectiles that are fired using multi-barrel weapons in highfrequency continuous firing modes are important indicators to measure the performance of these *** characteristics of multiple projectiles are high randomness and large numbers launched in a short period of time,making it very difficult to obtain the real dispersion parameters of the projectiles due to the occlusion or coincidence of multiple *** six intersecting-screen testing system,in this paper,we propose an association recognition and matching algorithm of multiple projectiles using a temporal and spatial information constraint *** extract the output signal from each detection screen and then use the wavelet transform to process the output *** present a method to identify and extract the time values on which the projectiles pass through the detection screens using the wavelet transform modulus maximum *** then use the correlation of the output signals of three parallel detection screens to establish a correlation coefficient recognition constraint function for the multiple *** on the premise of linear projectile motion,we establish a temporal and spatial constraint matching model using the projectile’s position coordinates in each detection screen and the projectile’s time constraints within the multiple intersecting-screen *** then determine the time values of the multiple projectiles in each detection screen using an iterative search cycle registration,and finally obtain the flight parameters for the multiple projectiles in the presence of *** proposed method and algorithm were verified experimentally and can solve the problem of uncertainty in projectiles flight parameter under different multiple projectile firing states.

关键词： Six detection screen array Multi-projectile Recognition and matching Temporal and spatial information constraint Wavelet transform

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Potential Distribution on Random Electrical Networks

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Acta Mathematicae Applicatae Sinica 2011年第3期27卷 549-559页

作者： Da-qian qian xiao-dong zhang Department of Mathematics Shanghai Jiao Tong University 800 Dongchuan Road Shanghai 200240 China

Let N = （G, c） be a random electrical network obtained by assigning a certain resistance for each edge in a random graph G ∈ G（n, p） and the potentials on the boundary vertices. In this paper, we prove that with ... 详细信息

关键词： Electrical network potential distribution random graphs

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Multi-area detection sensitivity calculation model and detection blind areas influence analysis of photoelectric detection target

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Defence Technology（防务技术） 2022年第4期18卷 547-556页

作者： Han-shan Li xiao-qian zhang Hui Guan School of Electronic and Information Engineering Xi’an Technological UniversityXi’an710021China

Multi-element array photoelectric detector is the core devices to form a photoelectric detection target with a large field of *** photoelectric detection target brings about the problem of uneven detection sensitivity distribution in the detection *** improve the uneven detection sensitivity of this photoelectric detection target,this paper analyzes the distribution law of the uneven detection sensitivity of the photoelectric detection target using the multi-element array photoelectric detector,dissects the main factors affecting the detection sensitivity according to the photoelectric detection principle,establishes the calculation model of detection sensitivity of the photoelectric detection target in the different detection areas and proposes a method to improve the detection sensitivity by compensating the gain of each unit photoelectric *** analysis of simulation and experimental results show that the proposed method of photoelectric detection target can effectively improve the output signal amplitude of the projectile under the certain detection distance,in particular,the output signal amplitude of the projectile is significantly increased when the projectile passes through the detection blind *** experimental results are consistent with the simulation results,which verify the effectiveness of the proposed improvement method.

关键词： Projectile Photoelectric detection target Multi-element array photoelectric detector Detection sensitivity Detection screen

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A line laser detection screen design and projectile echo power calculation in detection screen area

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Defence Technology（防务技术） 2022年第8期18卷 1405-1415页

作者： Han-shan Li xiao-qian zhang Xue-wei zhang Quan-min Guo School of Electronic and Information Engineering Xi'an Technological UniversityXi'an710021China

A line laser with high power as the background light source for the design of a new photoelectric detection target is proposed in this paper, aiming to improve the detection ability of the traditional photoelectric detection target under low background illumination. The laser emitted pulse waveform function and the laser echo pulse response function were used to establish the mathematical model of the reflected echo power of projectile in the detection area and derive the calculation function of minimum detectable echo power in the line laser detection screen, according to information of the line laser emitted power, incident angle of projectile, duration time and detection distance of projectile passing through the line laser detection screen. Calculations and experimental results showed that the design method of line laser detection screen and calculation model of laser echo power are reasonable, and the detection ability of line laser detection screen is obviously higher than that of traditional photoelectric detection screen, especially in low background illumination;at the same time, the designed line laser detection screen was used to combine a six line laser detection screen intersection test system, based on live ammunition for shooting. The test system is stable and able to obtain the dynamic parameters of the flying projectile, verifying that the design of the line laser detection screen in new photoelectric detection target can be suitable for shooting range test applications.

关键词： Line laser detection screen Photoelectric detection target Photoelectric detection receiver Echo power Projectile

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C-X-C chemokine receptor type 7 antibody enhances neural plasticity after ischemic stroke

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Neural Regeneration Research 2023年第9期18卷 1976-1982页

作者： xiao-qian zhang xiao-Yin Wang Bing-Chao Dong Mei-Xuan Li Yu Wang Ting xiao Shan-Shan Zhao Department of Neurology The First Hospital of China Medical UniversityShenyangLiaoning ProvinceChina Key Laboratory of Immunodermatology Ministry of HealthMinistry of EducationShenyangLiaoning ProvinceChina

Stromal cell-derived factor-1 and its receptor C-X-C chemokine receptor 4(CXCR4) have been shown to regulate neural regeneration after *** r,whether stromal cell-derived factor-1 receptor CXCR7,which is widely distributed in the develo ping and adult central nervous system,participates in neural regeneration remains poorly unde *** this study,we established rat models of focal cerebral ischemia by injecting endothelin-1 into the cerebral co rtex and *** on day 7 after injury,CXCR7-neutralizing antibody was injected into the lateral ventricle using a micro drug delivery system for 6 consecutive *** results showed that CXCR7-neutralizing antibody increased the total length and number of sprouting co rticospinal tra ct fibers in rats with cerebral ischemia,increased the expression of vesicular glutamate transporter 1 and growth-related protein 43,marke rs of the denervated spinal cord synapses,and promoted the differentiation and maturation of oligodendrocyte progenitor cells in the *** addition,CXCR7 antibody increased the expression of CXCR4 in the striatum,increased the protein expression of RAS and ERK1/2 associated with the RAS/ERK signaling pathway,and im proved rat motor *** findings suggest that CXCR7 improved neural functional recovery after ischemic stroke by promoting axonal regeneration,synaptogenesis,and myelin regeneration,which may be achieved by activation of CXCR4 and the RAS/ERK1/2 signaling pathway.

关键词： axonal regeneration cerebral ischemia C-X-C chemokine receptor 4 CXCR7 antibody neural plasticity RAS/ERK pathway remyelination stroke stromal cell-derived factor-1 synaptogenesis

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The general public’s ability to operate automated external defi brillator: A controlled simulation study

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World Journal of Emergency Medicine 2020年第4期11卷 238-245页

作者： Xue-jie Dong Lin zhang Yue-lin Yu Shu-xiao Shi xiao-chen Yang xiao-qian zhang Shuang Tian Helge Myklebust Guo-hong Li Zhi-jie Zheng School of Public Health Shanghai Jiao Tong UniversityShanghaiChina School of Medicine Shanghai Jiao Tong UniversityShanghaiChina Laerdal Medical StavangerNorway School of Public Health Peking UniversityBeijingChina

BACKGROUND:Automated external defibrillators(AEDs)enable laypeople to provide early defi brillations to patients undergoing cardiac arrest,but scant information is available on the general public’s ability to use *** study assessed the ability of laypeople to operate AEDs,the effect of a 15-minute training,and whether skills differed by ***:From May 1 to December 31,2018,a prospective simulation study was conducted with 94 laypeople aged 18–65 years(32 aged 18–24 years,34 aged 25–54 years,and 28 aged 55–65 years)with no prior AED *** participants’AED skills were assessed individually pretraining,post-training,and at a three-month follow-up using a simulated cardiac arrest *** critical actions and time intervals were evaluated during the AED operating ***:Only 14(14.9%)participants(eight aged 18–24 years,four aged 25–54 years,and two aged 55–65 years)successfully delivered defi brillations before *** operation errors were more likely to occur among the participants aged 55–65 years than among other age *** training,the proportion of successful defi brillations increased signifi cantly(18–24 years old:25.0%vs.71.9%,P<0.01;25–54 years old:11.8%vs.70.6%,P<0.01;55–65 years old:7.1%vs.67.9%,P<0.01).After three months,26.1%of the participants aged 55–65 years successfully delivered defi brillations,which was signifi cantly lower than that of participants aged 18–24 years(54.8%)and 25–54 years(64.3%)(P=0.02).There were no differences in time measures among three age groups in each ***:The majority of untrained laypeople cannot effectively operate *** frequent training and refresher courses are crucial to improve AED skills.

关键词： Automated external defi brillator Cardiac arrest General public Training Simulation

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Synergistically enhanced ORR and HER performance on Co-N-C coupled in-situ generated PtCo intermetallic

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Journal of Energy Chemistry 2025年第1期100卷 721-729页

作者： Guanyu Luo Min Song Lulu An xiao Huang qian zhang Chenhao zhang Tao Shen Shuang Wang Deli Wang Key Laboratory of Material Chemistry for Energy Conversion and Storage (Huazhong University of Science and Technology) Ministry of Education School of Chemistry and Chemical Engineering Huazhong University of Science and Technology

Integrating multi-scale sites in a composite catalyst is vital to realize efficient ***,a synergistic composite catalyst consisting of Co atomic sites and in-situ generated PtCo intermetallic compounds （IMCs）(o-PtCo@CoNC) is proposed through Co pre-anchoring and subsequent impregnation-reduction *** loading of Co atoms provides a chance for in-situ generating PtCo ordered intermetallic *** remaining Co single atoms and PtCo IMCs construct synergistic electrocatalytic *** from the ordered structure,synergistic effect of Pt Co IMCs and Co single atoms,o-PtCo@CoNC exhibits excellent electrocatalytic performance for oxygen reduction reaction （ORR） and hydrogen evolution reaction （HER） with mass activity of 1.21 A mgPt-1（at 0.9 V） and5.70 A mgPt-1（at an overpotential of 100 mV）,***,o-PtCo@CoNC delivers negligible loss of half-wave potential and overpotential during long-term stability test in acid solutions,with 13 mV decay after 50,000 potential cycles for ORR and a 2.7 mV decay after 20,000 potential cycles for *** integration strategy of single-atomic sites coupled IMCs paves the way for enhancing the activity and durability of Pt-based electrocatalysts.

关键词： Electrolytic reduction

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Esophageal mesenchymal tumors:Endoscopy,pathology and immunohistochemistry

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World Journal of Gastroenterology 2007年第5期13卷 768-773页

作者： Xuan Zhu xiao-qian zhang Bi-Min Li Ping Xu Kun-He zhang Jiang Chen Department of Gastroenterology First Affiliated Hospital Nanchang University Nanchang 330006 Jiangxi Province China Department of Digestive Diseases First Affiliated Hospital Nanchang University Nanchang 330006 Jiangxi Province China

AIM： To study the endoscopic, pathological and immunoo histochemical features of esophageal mesenchymal tumors. METHODS： Twenty-nine patients diagnosed as esophageal rnysenchymal tumors by electronic endoscopy and endoscopic ultrasound （EUS） were observed under light microscopes, and all tissues were stained by the immunohistochemical method. The expression of CD117, CD34, SMA and desmin were measured by staining intensity of cells and positive cell ratios. RESULTS： Endoscopically, esophageal gastrointestinal stromal tumors （GISTs） and leiomyomas （LMs） had similar appearances, showing submucosal protuberant lesions. They all showed low echo images originated from the muscularis propria or muscularis mucosa on EUS. Endoscopy and EUS could not exactly differentiate esophageal GISTs from LMs. Microscopically, there were two kinds of cells： spindle cell type and epitheloid cell type in esophageal GISTs. Leiomyomas and leiomyosarcornas were only of spindle cell type. One malignancy was found in five cases of esophageal GISTs, and one malignancy in 24 cases of leiomyomas and leiomyosarcomas. Using Fisher＇s exact method, the differences of malignant lesion proportion were not significant between esophageal LMs and GISTs, 1/5 vs 1/24 （P 〉 0.05）. All cases of esophageal GISTs were positive for CD117, and 3 cases were also positive for CD34. The 24 cases of leiomyomas and leiomyosarcomas were all negative for CD117 and CD34. The differences of positive rates of CD117 and CD34 were significant between esophageal GISTs and LMs, 5/5 vs 0/24, 3/5 vs 0/24 （P 〈 0.005）. All leiomyomas and leiomyosarcomas were positive for SMA, and desmin. Among 5 cases of esophageal GISTs, 2 cases were SMA positive, and 1 case was desmin positive. The differences in positive rates and expression intensity of SMA and desmin were significant between esophageal LMs and GISTs, 24/24 vs 2/5, 24/24 vs 115 （P 〈 0.005）. CONCLUSION： The most common esophageal mesenchymal tumors are leiomyomas, and esophageal

关键词： Esophageal mesenchymal tumors Gastrointestinal stromal tumors Leiomyomas Endoscopy Pathology Immunohistochemistry

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Emodin induces apoptosis in human prostate cancer cell LNCaP

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Asian Journal of Andrology 2008年第4期10卷 625-634页

作者： Chun-xiao Yu xiao-qian zhang Lu-Dong Kang Peng-Ju zhang Wei-Wen Chen Wen-Wen Liu Qing-Wei Liu Jian-Ye zhang Department of Biochemistry and Molecular Biology Shandong University School of Medicine Jinan 250012 China Merck Sharp ＆ Dohme Beijing 100738 China Positron Emission Tomography and Computer Tomography （PET-CT） Center Shandong Provincial Hospital Jinan 250021 China

Aim： To elucidate effects and mechanisms of emodin in prostate cancer cells. Methods： Viability of emodin-treated LNCaP cells and PC-3 cells was measured by MTT assay. Following emodin treatments, DNA fragmentation was assayed by agarose gel electrophoresis. Apoptosis rate and the expression of Fas and FasL were assayed by flow cytometric analysis. The mRNA expression levels of androgen receptor （AR）, prostate-specific antigen （PSA）, p53, p21, Bcl-2, Bax, caspase-3, -8, -9 and Fas were detected by RT-PCR, and the protein expression levels of AR, p53 and p21 were detected by Western blot analysis. Results： In contrast to PC-3, emodin caused a marked increase in apoptosis and a decrease in cell proliferation in LNCaP cells. The expression of AR and PSA was decreased and the expression of p53 and p21 was increased as the emodin concentrations were increased. In the same time, emodin induced apoptosis of LNCaP cells through the upregulation of caspase-3 and -9, as well as the increase of Bax/Bcl-2 ratio. However, it did not involve modulation of Fas or caspase-8 protein expression. Conclusion： In prostate cancer cell line, LNCaP, emodin inhibites the proliferation by AR and p53-p21 pathways, and induces apoptosis via the mitochondrial pathway.

关键词： emodin prostate cancer LNCaP PC-3 proliferation androgen receptor p53 apoptosis mitochondrial pathway

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