检索结果-南通市图书馆

A rapid compensation method for launch data of long-range rockets under influence of the Earth＇s disturbing gravity field

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Aeronautics 2017年第3期30卷 1196-1203页

作者： Baolin MA hongbo ZHANG wei ZHENG Jie WU College of Aerospace Science and Engineering National University of Defense Technology Changsha 410073 China

Regarding the rapid compensation of the influence of the Earth＇ s disturbing gravity field upon trajectory calculation,the key point lies in how to derive the analytical solutions to the partial derivatives of the state of burnout point with respect to the launch data.In view of this,this paper mainly expounds on two issues：one is based on the approximate analytical solution to the motion equation for the vacuum flight section of a long-range rocket,deriving the analytical solutions to the partial derivatives of the state of burnout point with respect to the changing rate of the finalstage pitch program;the other is based on the initial positioning and orientation error propagation mechanism,proposing the analytical calculation formula for the partial derivatives of the state of burnout point with respect to the launch azimuth.The calculation results of correction data are simulated and verified under different circumstances.The simulation results are as follows：（1） the accuracy of approximation between the analytical solutions and the results attained via the difference method is higher than 90%,and the ratio of calculation time between them is lower than 0.2%,thus demonstrating the accuracy of calculation of data corrections and advantages in calculation speed;（2） after the analytical solutions are compensated,the longitudinal landing deviation of the rocket is less than 20 m and the lateral landing deviation of the rocket is less than 10 m,demonstrating that the corrected data can meet the requirements for the hit accuracy of a long-range rocket.

关键词： Analytical solution Earth＇s disturbing gravity field Launch data Partial derivative compensation method Rapid compensation

Application of Improved Multi-Objective Ant Colony Optimization Algorithm in Ship Weather Routing

在线全文

学校读者我要写书评

暂无评论

Journal of Ocean University of China 2021年第1期20卷 45-55页

作者： ZHANG Guangyu WANG hongbo ZHAO wei GUAN Zhiying LI Pengfei State Key Laboratory on Integrated Optoelectronics College of Electronic Science and EngineeringJilin UniversityChangchun 130012China CRRC Changchun Railway Vehicles Co. Ltd.Changchun 130000China

This paper presents a novel intelligent and effective method based on an improved ant colony optimization(ACO)algorithm to solve the multi-objective ship weather routing optimization problem,considering the navigation safety,fuel consumption,and sailing time.Here the improvement of the ACO algorithm is mainly reflected in two aspects.First,to make the classical ACO algorithm more suitable for long-distance ship weather routing and plan a smoother route,the basic parameters of the algorithm are improved,and new control factors are introduced.Second,to improve the situation of too few Pareto non-dominated solutions generated by the algorithm for solving multi-objective problems,the related operations of crossover,recombination,and mutation in the genetic algorithm are introduced in the improved ACO algorithm.The final simulation results prove the effectiveness of the improved algorithm in solving multi-objective weather routing optimization problems.In addition,the black-box model method was used to study the ship fuel consumption during a voyage;the model was constructed based on an artificial neural network.The parameters of the neural network model were refined repeatedly through the historical navigation data of the test ship,and then the trained black-box model was used to predict the future fuel consumption of the test ship.Compared with other fuel consumption calculation methods,the black-box model method showed higher accuracy and applicability.

关键词： multi-objective optimization weather routing ACO algorithm fuel consumption

重构与优化:导生共同体内部失序和外部失联的破解之道——基于系统治理的视角

在线全文

学校读者我要写书评

暂无评论

学位与研究生教育 2022年第7期 55-62页

作者：危红波华东政法大学研究生院华东政法大学政治学与公共管理学院上海200042

处理好导师与研究生关系,加强导生共同体建设,是加快新时代研究生教育改革发展、推进研究生教育高质量发展的需要。针对目前导生共同体存在导生平等共治意识缺失、权责利分配结构失衡、协同合作机制不足等问题,提出理念重构,树立导生共... 详细信息

处理好导师与研究生关系,加强导生共同体建设,是加快新时代研究生教育改革发展、推进研究生教育高质量发展的需要。针对目前导生共同体存在导生平等共治意识缺失、权责利分配结构失衡、协同合作机制不足等问题,提出理念重构,树立导生共同体“五维度”系统治理理念;秩序重构,建构权责利明晰合理的治理体系;制度优化,建立健全导生共同体协同合作治理机制等重构与优化策略,以实现系统治理视域下导生共同体的权责共担、道德共守、价值共存、知行共进、成就共赢的内涵构建和功能价值。

关键词：研究生导师导生共同体制度优化系统治理

数字社会的法学教育因应--基于新文科建设视角的理论考察

在线全文

学校读者我要写书评

暂无评论

华东政法大学学报 2022年第3期25卷 169-176页

作者：危红波华东政法大学研究生院

在信息革命的强劲驱动下,新文科、新法学已经成为一种迫切的时代要求。这就使得法学教育面临着法学理论知识的数字更新、法学教育模式的复合探索、法学人才市场的供需重组等严峻挑战,法学教育转型已经势在必行。这既是构建数字社会秩序... 详细信息

在信息革命的强劲驱动下,新文科、新法学已经成为一种迫切的时代要求。这就使得法学教育面临着法学理论知识的数字更新、法学教育模式的复合探索、法学人才市场的供需重组等严峻挑战,法学教育转型已经势在必行。这既是构建数字社会秩序的需要、推进数字法治转型的需要,也是确立中国法学自主性的需要。因此,亟须确立面向数字法治的教育理念,塑造根植数字法学的知识体系,构建深度交叠互动的教育模式,进而为“数字中国”战略实施和数字法治建设提供可靠的人才支撑。

关键词：新文科新法学数字法学法学教育数字法治

直肠癌患者Denonvilliers筋膜的手术标识线及其解剖结构的确定

在线全文

学校读者我要写书评

暂无评论

癌症 2020年第5期39卷 226-232页

作者： Jianglong Huang Jing Liu Jiafeng Fang Zongheng Zeng Bo wei Tufeng Chen Hongbo Wei 中山大学附属第三医院胃肠外科广东广州510630 中国人体解剖学与组织胚胎学教研室广东药科大学广东广州510006

背景与目的传统的全直肠系膜切除术(total mesorectal excision,TME)后泌尿生殖功能障碍的发生率很高,这引发了学者们对解剖分离标准方式的质疑。我们提出了保留直肠癌患者Denonvilliers筋膜的必要性。但是,如何准确定位Denonvilliers... 详细信息

背景与目的传统的全直肠系膜切除术(total mesorectal excision,TME)后泌尿生殖功能障碍的发生率很高,这引发了学者们对解剖分离标准方式的质疑。我们提出了保留直肠癌患者Denonvilliers筋膜的必要性。但是,如何准确定位Denonvilliers筋膜尚不清楚。本研究旨在通过比较大体解剖结果和手术录像的观察结果来探究Denonvilliers筋膜的解剖特征,进而提出一种在直肠癌手术中保留盆腔自主神经的解剖方法。方法通过解剖5例成年男性大体标本,并回顾了2009年1月至2019年2月期间135例接受中低位直肠癌TME手术患者的手术录像,以鉴定和比较Denonvilliers筋膜的结构。结果在5例男性大体标本中对Denonvilliers筋膜的单层结构进行了观察,其位于直肠、膀胱底部、精囊、输精管和前列腺之间。Denonvilliers筋膜起源于直肠膀胱陷窝(或直肠子宫陷窝),向下与前列腺顶部的直肠尿道肌的末端融合,并融合至两侧的外侧韧带。筋膜在中线较薄,厚度为1.06±0.10 mm。Denonvilliers筋膜的冠状面形状略呈三角形,中线高度为5.42±0.16 cm。Denonvilliers筋膜的前方比后方神经分布密集,在两侧更为显著。在腹腔镜观察下,Denonvilliers筋膜起源于直肠膀胱陷窝(或直肠–子宫陷窝)的最低点,并带有一条加粗的白线,可作为识别Denonvilliers筋膜的良好标识。结论确定Denonvilliers筋膜的手术标识线可以帮助我们识别Denonvilliers筋膜,更好地保护直肠癌患者接受TME手术后的骨盆自主神经功能。

关键词：大体解剖腹腔镜手术保留盆腔自主神经直肠癌 Denonvilliers筋膜全直肠系膜切除

Highly oxidation-resistant Ti-Mo alloy with two-scale network Ti_(5)Si_(3)reinforcement

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2022年第15期110卷 24-34页

作者： Qiong Lu Yaozha Lv Chi Zhang hongbo Zhang wei Chen Zhanyuan Xu Peizhong Feng Jinglian Fan Powder Metallurgy Research Institute Central South UniversityChangsha 410083China Department of Mechanical Engineering Imperial College LondonExhibition RoadLondon SW72AZUK School of Materials Science and Engineering China University of Mining and TechnologyXuzhou 221116China

There is keen interest in using Ti alloys as lightweight structural materials for aerospace and automotive industries.However,a long-standing problem for these materials is their poor oxidation resistance.Herein,we designed and fabricated a Ti_(5)Si_(3) reinforced Ti-4(wt.%)Mo composite with two-scale network architecture by low energy milling and spark plasma sintering.It displays superior oxidation resistance at 800°C owing to the in-situ formation of a multi-component surface layer.This oxide layer has a dense grain size gradient structure that consists of an outer TiO_(2)layer and an inner SiO_(2)-padding-TiO_(2) layer,which has remarkable oxidation resistance and thermal stability.Furthermore,it was revealed that the hitherto unknown interaction between Ti_(5)Si_(3) reinforcement and nitrogen during oxidation would contribute to the formation of a TiN nano-twin interface layer,which accommodates the thermal mismatch strain between the oxide layer and matrix.This,along with high adhesion,confers excellent thermal cycling life with no cracking or spallation during long-term oxidation.In this regard,the secure operating temperature of this new composite can be increased to 800°C,which provides a design pathway for a new family of Ti matrix composites for high-temperature applications.

关键词： Ti matrix composites Oxidation mechanism Thermal stability Interface strengthening Transmission electron microscopy

Chemical looping oxidative propane dehydrogenation controlled by oxygen bulk diffusion over FeVO_(4)oxygen carrier pellets

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Chemical Engineering 2023年第1期53卷 409-420页

作者： hongbo Song wei Wang Jiachen Sun Xianhui Wang Xianhua Zhang Sai Chen Chunlei Pei Zhi-Jian Zhao Key Laboratory for Green Chemical Technology of Ministry of Education School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China Collaborative Innovation Center of Chemical Science and Engineering Tianjin 300072China Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192China Zhejiang Institute of Tianjin University Ningbo 315201China Joint School of National University of Singapore and Tianjin University International Campus of Tianjin UniversityBinhai New CityFuzhou 350207China Department of Chemistry National University of Singapore3 Science Drive 3117543Singapore

The oxygen distribution and evolution within the oxygen carrier exert significant influence on chemical looping processes.This paper describes the influence of oxygen bulk diffusion within FeVO4 oxygen carrier pellets on the chemical looping oxidative propane dehydrogenation(CL-ODH).During CL-ODH,the oxygen concentration at the pellet surface initially decreased and then maintained stable before the final decrease.At the stage with the stable surface oxygen concentration,the reaction showed a stable C3H6 formation rate and high C3H6 selectivity.Therefore,based on Fick’s second law,the oxygen distribution and evolution in the oxygen carrier at this stage were further analyzed.It was found that main reactions of selective oxidation and over-oxidation were controlled by the oxygen bulk diffusion.C3H8 conversion rate kept decreasing during this stage due to the decrease of the oxygen flux caused by the decline of oxygen gradient within the oxygen carrier,while C3H6 selectivity increased due to the decrease of overoxidation.In addition,reaction rates could increase with the propane partial pressure due to the increase of the oxygen gradient within the oxygen carrier until the bulk transfer reached its limit at higher propane partial pressure.This study provides fundamental insights for the diffusion-controlled chemical looping reactions.

关键词： Chemical looping Diffusion Reaction kinetics Oxygen carriers Oxidation

A Secure Mutual Authentication Scheme of Blockchain-Based in WBANs

在线全文

学校读者我要写书评

暂无评论

China Communications 2020年第9期17卷 34-49页

作者： Jianbo Xu Xiangwei Meng wei Liang hongbo Zhou Kuan-Ching Li School of Computer science and Engineering Hunan University of Science and TechnologyXiangtan 411201China College of Computer science and Electronic engineering Hunan UniversityChangsha 410082China School of Software Quanzhou University of Information engineeringQuanzhou 362000China Department of Computer Science and Information engineering Taichung 43301TaiwanChina

Wireless Body Area Networks(WBANs)refer to small sensor network that consists of sensor devices mounted on the surface of the body or implanted in the body,as such networks are employed to harvest physiological data of the human body or to act as an assistant regulator of several specific physiological indicators of the human body.The sensor devices transmit the harvested human physiological data to the local node via a public channel.Before transmitting data,the sensor device and the local node should perform mutual authentication and key agreement.It is proposed in this paper a secure mutual authentication scheme of blockchain-based in WBANs.To analyze the security of this scheme,formal security analysis,and informal security analysis are used,then the computation and communication costs are compared with those of the relevant schemes.Relevant experimental results reveal that the proposed scheme exhibit more effective control over energy consumption and promising.

关键词： information security authentication blockchain WBANs Real-or-Random model

Recent observations and research progresses of terrestrial gamma-ray flashes during thunderstorms

在线全文

学校读者我要写书评

暂无评论

Science China Earth Sciences 2023年第3期66卷 435-455页

作者： Fanchao LYU Yijun ZHANG Gaopeng LU Baoyou ZHU hongbo ZHANG wei XU Shaolin XIONG weitao LYU Key Laboratory of Transportation Meteorology of China Meteorological Administration Nanjing Joint Institute for Atmospheric SciencesNanjing 210041China State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081China Institute of Atmospheric Sciences Fudan UniversityShanghai 200441China School of Earth and Space Sciences University of Science and Technology of ChinaHefei 230026China Key Laboratory of Middle Atmosphere and Global Environment Observation Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100081China Electronic Information School Wuhan UniversityWuhan 430072China Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100081China

Terrestrial gamma-ray flashes(TGFs)are high-energy emissions in thunderstorms that were discovered first by satellite-based and then by ground-based gamma-ray detectors with photon energy up to tens of Me V.TGFs are a natural highenergy phenomenon associated with lightning discharges that frequently occur during thunderstorms.However,their production mechanisms and associated processes are still unclear.TGF studies have already been a research spotlight in the atmospheric electricity and high-energy atmosphere research areas.In this paper,we review recent research progresses on TGF studies in the past decade,including TGF detection,the relationship between TGFs and lightning processes,and thunderstorm activities.Several unsolved important scientific questions are discussed.Results suggest that upward TGFs observed by satellite-based detectors are closely connected with the development of in-cloud upward negative leaders.They are usually generated in milliseconds of the initiation of upward negative leaders and may produce a kind of distinct radio emissions because of the generation and propagation of huge amounts of high-energy electrons.By contrast,its counterpart,i.e.,downward TGFs observed by ground-based gamma-ray detectors,is associated with different types of lightning processes,such as downward negative or upward positive leaders,the initial continuing current stage of rocket-triggered lightning flashes return stroke processes.Because of limited observations,how these downward TGFs are generated is still unclear.Benefiting from the development of state-of-the-art instruments with high temporal and spatial resolutions,new insights into the processes and mechanisms of TGFs will be achieved with coordinated observations from satellite-based and ground-based measurements.

关键词： Terrestrial gamma-ray flashes(TGFs) Lightning Thunderstorm High-energy emissions Radio emission detection