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Sensor management of LEO constellation based on covariance control

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Journal of Systems Engineering and Electronics 2019年第2期30卷 393-401页

作者： qin Zheng LIANG Yan'gang College of Aerospace Science and Engineering National University of Defense Technology

This paper studies the multi-sensor management problem for low earth orbit(LEO) infrared warning constellation used to track a midcourse missile. A covariance control approach, which selects sensor combinations or subset based on the difference between the desired covariance matrix and the actual covariance of each target, is used for sensor management, including some matrix metrics to measure the differentia between two covariance matrices. Besides, to meet the requirements of the space based warning system, the original covariance control approach is improved. Simulation results demonstrate that the covariance control approach is able to provide a better tracking performance by providing a well-designed desired covariance and balance tracking performance goals with system demands.

关键词： sensor management covariance control target tracking accuracy LEO constellation

A decision support system for satellite layout integrating multi-objective optimization and multi-attribute decision making

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Journal of Systems Engineering and Electronics 2019年第3期30卷 535-544页

作者： LIANG Yan’gang qin Zheng College of Aerospace Science and Engineering National University of Defense Technology

A decision support system, including a multi-objective optimization framework and a multi-attribute decision making approach is proposed for satellite equipment layout. Firstly, given three objectives (to minimize the C.G. offset, the cross moments of inertia and the space debris impact risk), we develop a threedimensional layout optimization model. Unlike most of the previous works just focusing on mass characteristics of the system, a space debris impact risk index is developed. Secondly, we develop an efficient optimization framework for the integration of computer-aided design (CAD) software as well as the optimization algorithm to obtain the Pareto front of the layout optimization problem. Thirdly, after obtaining the candidate solutions, we present a multi-attribute decision making approach, which integrates the smart Pareto filter and the correlation coefficient and standard deviation (CCSD) method to select the best tradeoff solutions on the optimal Pareto fronts. Finally, the framework and the decision making approach are applied to a case study of a satellite platform.

关键词： layout optimization satellite multi-objective optimization Pareto front multi-attribute decision making

Pore-scale modeling of pore structure properties and wettability effect on permeability of low-rank coal

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International Journal of Mining Science and Technology 2023年第5期33卷 573-584页

作者： Xiangjie qin Jianchao Cai gang Wang State Key Laboratory of Petroleum Resources and Prospecting China University of PetroleumBeijing 102249China State Key Laboratory of Mining Disaster Prevention and Control Cofounded by Shandong Province and the Ministry of Science and Technology Shandong University of Science and TechnologyQingdao 266590China

Permeability is a key parameter for coalbed methane *** the absolute permeability of coal has been extensively studied,wettability and pore structure properties continue to challenge the microscopic description of water-gas flow in *** this purpose,we reconstructed the microstructures of low-rank coal using micro-computed tomography(micro-CT)*** geometry and pore-throat parameters are introduced to establish a relationship with absolute permeability.A dual-porosity pore network model is developed to study water-gas displacement under different wetting and pore structure *** show that absolute permeability is significantly affected by pore geometry and can be described using a binary quadratic function of porosity and fractal ***-gas relative permeability varies significantly and the residual gas saturation is lower;the crossover saturation first decreased and then increased with increasing porosity under hydrophobic *** the water relative permeability is lower and a certain amount of gas is trapped in complex pore-throat networks;the crossover saturation is higher under hydrophilic *** with large percolating porosity and well-developed pore networks have high displacement efficiency due to low capillary resistance and avoidance of *** work provides a systematic description of absolute permeability and water-gas relative permeability in coal microstructure for enhanced gas recovery.

关键词： Micro-CT Permeability Wetting condition Pore structure properties Water-gas flow

Engineered Cancer Nanovaccines:A New Frontier in Cancer Therapy

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Nano-Micro Letters 2025年第2期17卷 134-168页

作者： Yijie Wang Congrui Liu Chao Fang Qiuxia Peng Wen qin Xuebing Yan Kun Zhang Central Laboratory and Department of Medical Ultrasound Sichuan Academy of Medical SciencesSichuan Provincial People’s HospitalSchool of MedicineUniversity of Electronic Science and Technology of ChinaNo.32West Second SectionFirst Ring RoadChengdu 610072People’s Republic of China Department of Stomatology and Central Laboratory School of MedicineShanghai Tenth People’s HospitalTongji UniversityNO.301 Yan‑Chang‑Zhong RoadShanghai 200072People’s Republic of China Jiangsu Provincial Innovation and Practice Base for Postdoctors Suining People’s HospitalAffiliated Hospital of Xuzhou Medical UniversityNo.2Bayi West RoadSuiningXu Zhou 221000Jiangsu ProvincePeople’s Republic of China

Vaccinations are essential for preventing and treating disease,especially cancer nanovaccines,which have gained considerable interest recently for their strong anti-tumor immune *** can prompt the immune system to generate antibodies and activate various immune cells,leading to a response against tumor tissues and reducing the negative effects and recurrence risks of traditional chemotherapy and *** enhance the flexibility and targeting of vaccines,nanovaccines utilize nanotechnology to encapsulate or carry antigens at the nanoscale level,enabling more controlled and precise drug delivery to enhance immune *** nanovaccines function by encapsulating tumor-specific antigens or tumor-associated antigens within *** small size of these nanomaterials allows for precise targeting of T cells,dendritic cells,or cancer cells,thereby eliciting a more potent anti-tumor *** this paper,we focus on the classification of carriers for cancer nanovaccines,the roles of different target cells,and clinically tested cancer nanovaccines,discussing strategies for effectively inducing cytotoxic T lymphocytes responses and optimizing antigen presentation,while also looking ahead to the translational challenges of moving from animal experiments to clinical trials.

关键词： Cancer nanovaccines Immunotherapy Nanobiotechnology Immune targets Signaling pathway

Surface Texturing of TiO_2 Film by Mist Deposition of TiO_2 Nanoparticles

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Nano-Micro Letters 2013年第2期5卷 129-134页

作者： gang qin Akira Watanabe Institute of Multidisciplinary Research for Advanced Materials Tohoku University School of Materials Science and Engineering Henan Polytechnic University

Unique and various microstructures of titanium oxide(TiO_2 ) film including macroporous structure, chromatic veins and rings, have been easily fabricated by mist deposition method on silicon substrate with mild preparation conditions. Rutile phase TiO_2 nanoparticles were directly used as starting material to prepare film and led to a simple preparation process. It was found that several different microstructures existed in the sample and changed with the varied positions from the center to the edge of the film when the concentration of the TiO_2 suspension is 0.06 mol/l, the deposition time is 30 min, the flow rate is 1 l/min and the temperature is150. The surface texturing shows apparent distinction as the concentration of the TiO_2 suspension decreased to 0.03 mol/l and 0.01 mol/l.

关键词： Mist deposition TiO2 film TiO2 nanoparticle Surface texturing Microstructure

Filling mode and regularity of vertical centrifugal casting process of titanium alloy in thin-walled cylinder cavity

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China Foundry 2019年第2期16卷 105-109页

作者： qin Xu Xing Wang Yong-gang guo Shi-ping Wu School of Mechanical and Electrical Engineering Henan University of Technology School of Materials Science and Engineering Harbin Institute of Technology

The mold filling process of titanium alloy in a thin-walled cylinder cavity under vertical centrifugal casting process was studied by means of the hydraulic simulation experiments. Results show that the filling mode of the melt in the cylinder cavity varies with casting wall-thickness. When the casting wall-thickness is less than or equal to the thickness of the first layer during the filling process, the melts fill the cavity from the bottom to the *** the casting wall-thickness is greater than the thickness of the first layer during the filling process, the melts first fill the largest radius parts of the cavity with a certain thickness of the first layer from the bottom to the top of the cavity, and then they fill the cavity from the larger radius part to the smaller radius part. The melt filling ability increases with the increment of the mold rotational speed and the pouring temperature. In another aspect, the melt filling ability rises with the decrement of the melt viscosity, and the melt with the better filling ability is prone to fill the cylinder cavity layer by layer.

关键词： titanium alloy thin-walled casting vertical centrifugal casting cylinder-shape cavity hydraulic experiment mold filling

Performance measure for image fusion considering region information

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第4期8卷 559-562页

作者： LIU gang Lü Xue-qin School of Power and Automation Engineering Shanghai University of Electric Power Shanghai 200093 China

An objective performance measure for image fusion considering region information is proposed. The measure not only reflects how much the pixel level information that fused image takes from the source image, but also considers the region information between source images and fused image. The measure is meaningful and explicit. Several simulations were conducted to show that it accords well with the subjective evaluations.

关键词： Image fusion Information fusion Image processing

Population dynamics and protection strategies of Litsea coreana *** with Guizhou Province in China as an example

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Journal of Mountain Science 2023年第4期20卷 1090-1101页

作者： YUAN gang-yi guo Qi-qiang XIE Na ZHANG Ya-qin LUO Si-qiong GUI qin YAO Shan Institute for Forest Resources and Environment of Guizhou College of ForestryGuizhou UniversityGuiyang550025China

Studying the dynamics of plant populations is crucial to the conservation and management of endangered *** diameter at breast height(DBH),tree height,crown width,and environmental factors of a total of 15 plots in five populations in Guizhou Province,China were measured in this *** method of substituting diameter at breast height for age was used to divide the population into 7 age *** age structure,static life table,and relationship between the population characteristics and environmental factors of the Litsea coreana *** population were ***,the time series model was used to predict the population *** showed that the age structure of population in Zhengan County(Population ZA)had an inverted Jshape with abundant seedlings and insufficient middle-aged and elderly *** age structures of populations in Daozhen County(Population DZ),Kaiyang County(KY),Meitan County(Population MT),and Xishui County(Population XS)were spindle-shaped with few young individuals and many middle-aged and elderly *** mortality rate of each population fluctuated with the increase in age class,and the populations were extremely *** survival curve was close to the Deevey III type,and the degree of deviation was related to the lack of young *** the age stages II,IV,and VI,the number of aged plants in the different populations initially increased then decreased,and population stability was difficult to *** analysis showed that the DBH,tree height and crown width of the population decreased with the increase of annual mean temperature,and the population density was restricted by soil nutrient conditions to a certain *** results of this work provide scientific basis for the conservation and sustainable utilization of natural populations of *** *** in Guizhou Province,China.

关键词： Litsea coreana var.sinensis Age structure Survival curve Time series prediction Environmental factor

非货币激励因素对中小学教师工作满意度的影响——基于云贵川渝的调查

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教师教育学报 2025年第1期12卷 106-115页

作者：周琴郭瑜琦西南大学教师教育学院重庆400715

教师工作满意度是影响教师工作效能、促进教师可持续发展的重要因素。研究采用TALIS 2018教师问卷对云贵川渝4个省份的中小学教师展开抽样调查。数据分析显示,该地区教师工作满意度处于较高水平,但内部群体间存在显著性差异。回归分析发... 详细信息

教师工作满意度是影响教师工作效能、促进教师可持续发展的重要因素。研究采用TALIS 2018教师问卷对云贵川渝4个省份的中小学教师展开抽样调查。数据分析显示,该地区教师工作满意度处于较高水平,但内部群体间存在显著性差异。回归分析发现,云贵川渝4省份中小学教师工作满意度受工资薪酬以及其他非货币因素的影响。比较分析发现,云贵川渝初中教师对工资薪酬的接受度高于上海同行,但对社会认可、媒体关注等非货币激励因素的认可程度却低于上海教师,从而使其工作满意度整体水平低于上海。研究认为,坚持教育家精神铸魂强师的同时提升教师工作满意度,需要在巩固提高工资薪酬水平的基础上,进一步从优化教师工作体验、提高教师学历、打通职业晋升渠道、营造尊师重教良好氛围等非货币因素着手,在满足教师内在需求的同时,为加快教育现代化、建设教育强国、办好人民满意的教育提供有力支撑。

关键词：中小学教师工作满意度工资非货币激励双因素理论