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Dynamic simulation of aerial towed decoy system based on tension recurrence algorithm

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Chinese Journal of Aeronautics 2016年第6期29卷 1484-1495页

作者： Ma Dongli wang shaoqi Yang Muqing Dong Yongpan School of Aeronautic Science and Engineering Beihang University

Dynamic model of aerial towed decoy system is established and simulations are performed to research the dynamic characteristics of the system. Firstly, Kinetic equations based on spinor are built, where the cable is discretized into a number of rigid segments while the decoy is modeled as a rigid body hinged on the cable. Then tension recurrence algorithm is developed to improve computational efficiency, which makes it possible to predict the dynamic response of aerial towed decoy system rapidly and accurately. Subsequently, the efficiency and validity of this algorithm are verified by comparison with Kane’s function and further validated by wind tunnel *** results indicate that the distance between the towing point and the decoy’s center of gravity is suggested to be 5%–20% of the length of decoy body to ensure the stability of *** up-risen maneuver process, the value of angular velocity is recommended to be less than0.10 rad/s to protect the cable from the aircraft exhaust jet. During the turning movement of aircraft, the cable’s extent of stretching outwards is proportional to the aircraft’s angular ***, the decoy, aircraft and missile form a triangle, which promotes the decoy’s performance.

关键词： Numerical simulation Spinor Tension recurrence algorithm Towed cable Towed decoy

Flight strategy optimization for high-altitude long-endurance solar-powered aircraft based on Gauss pseudo-spectral method

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Chinese Journal of Aeronautics 2019年第10期32卷 2286-2298页

作者： shaoqi wang Dongli MA Muqing YANG Liang ZHANG Guanxiong LI School of Aeronautic Science and Engineering Beihang University

Solar-powered aircraft have attracted great attention owing to their potential for longendurance flight and wide application *** to the particularity of energy system,flight strategy optimization is a significant way to enhance the flight performance for solar-powered *** this study,a flight strategy optimization model for high-altitude long-endurance solar-powered aircraft was *** model consists of three-dimensional kinematic model,aerodynamic model,energy collection model,energy store model and energy loss *** solve the nonlinear optimal control problem with process constraints and terminal constraints,Gauss pseudo-spectral method was employed to discretize the state equations and constraint *** a typical mission flying from given initial point to given final point within a time interval was *** indicate that proper changes of the attitude angle contribute to increasing the energy gained by photovoltaic *** of gravitational potential energy can partly take the role of battery *** these two measures,the optimized flight strategy can improve the final state of charge compared with current constant-altitude constant-velocity *** optimized strategy brings more profits on condition of lower sunlight intensity and shorter daytime.

关键词： Battery pack Flight strategy optimization Gauss pseudo-spectral method Photovoltaic cell Solar-powered aircraft

冻结液滴融化阶段相变过程与多相态分布定性分析

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低温工程 2024年第3期 45-55页

作者：张哲王少启刘训杰田津津郎元路张靖含天津商业大学天津市制冷技术重点实验室天津300314

采用基于CCD高速图像观测法,以不同基底表面、不同基底表面温度为工况,研究了冻结液滴融化阶段的不同动态演化过程和相态分布特性。结果表明:金属类基底表面冻结液滴在融化过程中,内部气泡体积较小,分布较密集;聚合物类基底表面的冻结... 详细信息

采用基于CCD高速图像观测法,以不同基底表面、不同基底表面温度为工况,研究了冻结液滴融化阶段的不同动态演化过程和相态分布特性。结果表明:金属类基底表面冻结液滴在融化过程中,内部气泡体积较小,分布较密集;聚合物类基底表面的冻结液滴在融化过程中,内部气泡体积较大,气泡聚集在固相区域周边及顶部。冻结速率对气泡的大小产生了重要影响,冻结速率越小产生的气泡体积越大,冻结速率越大产生的气泡体积越小;金属基底表面液滴在润湿过程中表现出明显的前驱膜,聚合物表面则未出现这一现象;聚合物表面冻结液滴内部的孔隙区域较大,金属表面则相反,孔隙内的水分布对冰晶融化有着促进作用。

关键词：液滴冻结融化形态演化多相分布

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PMMA低温表面液滴凝结过程的实验研究

低温与超导 2024年第1期52卷 36-42,86页

作者：张哲张靖含王晓霞田津津法静秀王少启刘训杰天津商业大学天津市制冷技术重点实验室天津300134

为了解不同温度下有机玻璃(PMMA)表面蒸汽凝结相变、液滴生长以及传热的过程,对有机玻璃表面的液滴冷凝过程进行了可视化实验观测,将液滴的凝结形态、面积率、接触角及尺寸变化等参数进行了分析并绘制出变化曲线,发现蒸汽在有机玻璃表... 详细信息

为了解不同温度下有机玻璃(PMMA)表面蒸汽凝结相变、液滴生长以及传热的过程,对有机玻璃表面的液滴冷凝过程进行了可视化实验观测,将液滴的凝结形态、面积率、接触角及尺寸变化等参数进行了分析并绘制出变化曲线,发现蒸汽在有机玻璃表面凝结时可形成颗粒分明的珠状液滴,凝结时间越长液滴直径越大;底板温度越低,面积率越大,接触角越大。控制以上变量可以有效改善蒸汽凝结效果,有利于提高热量传递效率,为液滴相变(汽-液)特性和换热表面结霜除霜技术提供理论支持。

关键词：蒸汽凝结接触角面积率扩散性

Current Status of Studies on Targeted Therapy for Renal Cell Carcinoma

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Chinese Journal of Clinical Oncology 2008年第4期5卷 294-298页

作者： shaoqi wang Shaoxiang wang Juan wang Department of Oncology Hebei People＇s Hospital Shijiazhuang 050051 Hebei Province China. Shenzhen People＇s Hospital Shenzhen 518020 Guangdong Province China.

Renal cell carcinoma(RCC)is regarded as one of the most refractory malignancies.A further study of the molecular mechanism of RCC formation has led to a series of successful examples for treatment of patients with advanced *** the past 20 years,a nonspecific immunotherapy,with cytokines,has been employed as the gold standard for therapy of metastatic ***,with scientific development and clinical testing of new drugs,targeted molecular cancer therapy has become a focus of *** the same time,with a better understanding of RCC, the treatment method has converged on anti-vascular endothelial growth factor(VEGF)and related molecular-targeted pathways. A large amount of research and numerous clinical trials have demonstrated the clinical efficacy of the targeted molecular therapies in patients with metastatic *** example sorafenib and sunitinib were approved,in 2005 and 2006 respectively,by the *** for treating advanced *** this report,issues such as the importance of VEGF in RCC and the studies of bevacizumab, sunitinib and sorafenib in treating metastatic RCC etc.,are reviewed.

关键词： targeted molecular therapy renal cell carcinoma vascular endothelial growth factor.

Degradation of Acid Orange Ⅱ Using Negative Pulsed Discharge Plasma from a Nozzle-cylinder Electrode Coated with TiO2

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高电压技术 2013年第10期39卷 2514-2519页

作者： SUN Ming wang shaoqi ZHANG Ying Institute of Electrostatics Shanghai Maritime University Shanghai 200135 China

Many sub-products of pulsed discharge,such as ultraviolet light,strong electric fields,shock waves and active species,are effective in treating *** improve the efficiency of the discharge plasma technology in removing pollutants,adding TiO2 photo-catalyst to pulsed discharges could help.A negative-pulsed-discharge system,which has nozzle discharge electrodes with or without TiO2 coating,is used to degrade azo dye Acid Orange Ⅱ,and the effects of several key conditions(maximum pulse voltage,pulse repetition frequency,initial mass concentration of Acid Orange Ⅱ initial solution pH,treatment duration,the phase of discharge,and the existence of TiO2) on the degradation are experimentally *** degradation of Acid Orange Ⅱ increases with maximum pulse voltage,pulse repetition frequency,and treatment duration,and it is larger when putting the discharge electrode on the solution surface than in air or inside the solution,*** discharge in gas phase is more effective than that in gas-liquid phase or liquid *** degradation decreases as the initial mass concentration of the solution *** also relates to pH and is higher at acidic conditions than at neutral or alkaline *** to treatments without TiO2,the ones using the nozzle discharge electrode with TiO2 coated increase the degradation of Acid Orange Ⅱ by 5 %.It is concluded that the proposed system with TiO2 added in can remove Acid Orange Ⅱ from wastewater effectively.

关键词：脉冲放电等离子体 TiO2光催化剂酸性橙Ⅱ 放电电极降解表面覆盖喷嘴二氧化钛涂层

ReaxFF-MD simulation investigation of the degradation pathway of phenol for hydrogen production by supercritical water gasification

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Energy Storage and Saving 2023年第4期2卷 578-585页

作者： Deming Zhang shaoqi wang Yu Feng Zixuan wang Hui Jin School of Mechanical Engineering and Automation Harbin Institute of TechnologyShenzhenGuangdong518055China Institute of Intelligent Ocean Engineering Harbin Institute of TechnologyShenzhenGuangdong518055China State Key Laboratory of Multiphase Flow in Power Engineering(SKLMF) Xi’an Jiaotong UniversityXi’an710049China

Wastewater from the thermochemical conversion of coal and biomass contains a significant amount of phenolic structures *** degradation of these phenolic compounds to hydrogen-rich gasses can prevent envi-ronmental pollution and save *** water(SCW)gasification of phenol is experimentally studied and a reactive force field molecular dynamics(ReaxFF-MD)simulation is conducted to investigate the catalytic mechanism of Ni/Al2 O3 in the phenol *** experimental results indicate that Ni/Al2 O3 facilitates the conversion of phenol to 1-ethoxy butane via ring opening,which is a crucial step for complete *** ReaxFF-MD simulation demonstrated that Ni facilitates the formation of H3 O free radicals and Ni-phenol inter-mediates.H3 O free radicals can be decomposed into H2 and OH free *** the generated OH free radical and Ni-phenol intermediate promote the ring-opening reaction of *** promotes the direct decomposition of phenol into C1,C2,and C3 fragments,which is beneficial for further complete gasification.

关键词： Supercritical water gasification Phenol degradation Ring opening process ReaxFF-MD

融合密集空洞注意力金字塔和多尺度的视网膜病变分割

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中国医学物理学杂志 2024年第8期41卷 1000-1009页

作者：王志鲁池越周亚同单春艳肖志涛王劭奇河北工业大学电子信息工程学院天津300401 天津医科大学朱宪彝纪念医院/天津市内分泌研究所/国家卫健委激素与发育重点实验室/天津市代谢性疾病重点实验室天津300134 天津工业大学生命科学学院天津300387

针对糖尿病视网膜病变(DR)分割任务中病变区域多尺度特征难以学习、边界模糊等问题,提出一种改进的U型多病变分割模型DDAPNet。首先,对DR图像进行Patch处理,使模型更好地捕捉病变的局部特征;其次在主干特征提取后引入重新设计的密集空... 详细信息

针对糖尿病视网膜病变(DR)分割任务中病变区域多尺度特征难以学习、边界模糊等问题,提出一种改进的U型多病变分割模型DDAPNet。首先,对DR图像进行Patch处理,使模型更好地捕捉病变的局部特征;其次在主干特征提取后引入重新设计的密集空洞注意力金字塔(DDAP)模块,扩大感受野,解决病变边界模糊问题;同时采用金字塔切分注意力进行特征增强,然后将二者进行特征融合;最后在跳跃连接中嵌入改进的残差注意力模块,降低浅层冗余信息的干扰。在数据集和医院真实数据集上进行联合验证,实验结果表明,相较于基础模型,DDAPNet模型对微动脉瘤、出血点、软渗出DDR物和硬渗出物的分割在Dice系数上分别提高了4.31%、2.52%、3.39%、4.29%,在mIoU上分别提高了1.80%、2.24%、4.28%、1.98%。该模型对病灶边缘的分割更为连续和平滑,有效提升了软渗出物等视网膜病变的分割性能。

关键词：糖尿病视网膜病变密集空洞注意力金字塔多尺度特征残差模块

Self-supervised recalibration network for person re-identification

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Defence Technology（防务技术） 2024年第1期31卷 163-178页

作者： shaoqi Hou Zhiming wang Zhihua Dong Ye Li Zhiguo wang Guangqiang Yin Xinzhong wang Shenzhen Institute of Information Technology Shenzhen518172China University of Electronic Science and Technology of China Chengdu611731China Kash Institute of Electronics and Information Industry Kashi844099China

The attention mechanism can extract salient features in images,which has been proved to be effective in improving the performance of person re-identification(Re-ID).However,most of the existing attention modules have the following two shortcomings:On the one hand,they mostly use global average pooling to generate context descriptors,without highlighting the guiding role of salient information on descriptor generation,resulting in insufficient ability of the final generated attention mask representation;On the other hand,the design of most attention modules is complicated,which greatly increases the computational cost of the *** solve these problems,this paper proposes an attention module called self-supervised recalibration(SR)block,which introduces both global and local information through adaptive weighted fusion to generate a more refined attention *** particular,a special"Squeeze-Excitation"(SE)unit is designed in the SR block to further process the generated intermediate masks,both for nonlinearizations of the features and for constraint of the resulting computation by controlling the number of ***,we combine the most commonly used Res Net-50 to construct the instantiation model of the SR block,and verify its effectiveness on multiple Re-ID datasets,especially the mean Average Precision(m AP)on the Occluded-Duke dataset exceeds the state-of-the-art(SOTA)algorithm by 4.49%.

关键词： Person re-identification Attention mechanism Global information Local information Adaptive weighted fusion