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Artificial Sun synchronous frozen orbit control scheme design based on J_2 perturbation

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Acta Mechanica Sinica 2011年第5期27卷 809-816页

作者： Gong-Bo Wang Yun-He Meng Wei Zheng guo-jian tang College of Aerospace and Material Engineering National University of Defense Technology410073 Changsha China

Sun synchronous orbit and frozen orbit formed due to J 2 perturbation have very strict constraints on orbital parameters,which have restricted the application a *** this paper,several control strategies were illustrated to realize Sun synchronous frozen orbit with arbitrary orbital elements using continuous ***,according to mean element method,the averaged rate of change of the orbital elements,originating from disturbing constant accelerations over one orbital period,was derived from Gauss＇ variation of parameters ***,we proposed that binormal acceleration could be used to realize Sun synchronous orbit,and radial or transverse acceleration could be adopted to eliminate the rotation of the argument of the ***,amending methods on the control strategies mentioned above were presented to eliminate the residual secular *** results showed that the control strategies illustrated in this paper could realize Sun synchronous frozen orbit with arbitrary orbital elements,and can save much more energy than the schemes presented in previous studies,and have no side effect on other orbital parameters＇ secular motion.

关键词： Continuous low-thrust Artificial Sun synchronous orbit Artificial frozen orbit Gauss' variation of parameters equations Mean element method

Suppression of low-frequency ultrasound broadband vibration using star-shaped single-phase metamaterials

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Defence Technology（防务技术） 2024年第4期34卷 217-224页

作者： Rui Zhao jian Zheng Jin guo Yunbo Shi Hengzhen Feng Jun tang Jun Liu Science and Technology on Electronic Test&Measurement Laboratory North University of ChinaTaiyuan 030051ShanxiChina School of Mechatronical Engineering Beijing Institute of TechnologyBeijing 100081China

In order to suppress the low-frequency ultrasound vibration in the broadband range of 20 k Hz—100 k Hz,this paper proposes and discusses an acoustic metamaterial with low-frequency ultrasound vibration attenuation properties,which is configured by hybrid arc and sharp-angle convergent star-shaped *** effect of the dispersion relation and the bandgap characteristic for the scatterers in star-shaped are simulated and *** target bandgap width is extended by optimizing the geometry parameters of arc and sharp-angle convergent *** proposed metamaterial configured by optimized hybrid lattices exhibits remarkable broad bandgap characteristics by bandgap complementarity,and the simulation results verify a 99%vibration attenuation amplitude can be obtained in the frequency of20 k Hz—100 k *** the fabrication of the proposed hybrid configurational star-shaped metamaterial by 3D printing technique,the transmission loss experiments are performed,and the experimental results indicate that the fabricated metamaterial has the characteristics of broadband vibration attenuation and an amplitude greater than 85%attenuation for the target *** results demonstrate that the hybrid configurational star-shaped metamaterials can effectively widen the bandgap and realize high efficiency attenuation,which has capability for the vibration attenuation in the application of highprecise equipment.

关键词： Star-shaped metamaterials Broadband Vibration attenuation Low-frequency ultrasound vibration Transmission loss

Effect of alumina occurrence form on metallurgical properties of hematite and magnetite pellets

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Journal of Iron and Steel Research International 2024年第4期31卷 797-809页

作者： jian Pan Chen-mei tang Cong-cong Yang De-qing Zhu Zheng-qi guo Wei-qun Huang School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083HunanChina Exploration and Development of Geology and Mineral Resources Co. Ltd.Nanchang 330030JiangxiChina

The effect of alumina occurrence form on the metallurgical properties of both hematite and magnetite pellets was investigated at the same Al_(2)O level of 2 wt.%,including reduction index(RI),low-temperature reduction disintegration index(RDI),reduction swelling index(RSI),and high-temperature softening-dripping *** mineralogy of fired pellets was also studied to reveal the influence of alumina occurrence form on the phase composition and *** the results,the alumina occurrence form presents tremendous impacts on the metallurgical perfor-mance of both magnetite and hematite *** of all alumina occurrence forms contributes to inferior reducibility of pellets,especially in the case of gibbsite for magnetite pellets with a RI of 58.4%and kaolinite for hematite pellets with a RI of 56.8%.However,addition of all alumina occurrence forms improves the RDI of magnetite pellets,while there is no significant difference among various alumina occurrence *** contrast,alumina occurrence forms have little influence on the RDI of hematite *** presence of free alumina,gibbsite,and kaolinite tends to improve the RSI of hematite and magnetite pellets,whereas hercynite gives the opposite trend with a RSI of 25.6%.For softening-dripping performance of magnetite pellets,all alumina occurrence forms contribute to narrower softening-melting ***,alumina,gibbsite,and kaolinite give narrower softening-dripping interval,at 229,217,and 88℃,respectively,whereas addition of hercynite results in the largest melting range at 276℃ due to its high melting *** hematite pellets,free alumina,gibbsite,and hercynite tend to enlarge melting range,whereas kaolinite contributes to lower dripping temperature of 1148℃ and narrow softening-dripping interval of 88℃ due to the formation of a greater amount of slag phase at high temperatures.

关键词： Oxidized pellet Magnetite Hematite Alumina occurrence form Metallurgical performance Blast furnace

Harnessing data using symbolic regression methods for discovering novel paradigms in physics

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Science China(Physics,Mechanics & Astronomy) 2024年第6期67卷 1-11页

作者： jianyang guo Wan-jian Yin College of Energy Soochow Institute for Energy and Materials Innovations(SIEMIS)Jiangsu Provincial Key Laboratory for Advanced Carbon Materials and Wearable Energy TechnologiesSoochow UniversitySuzhou 215006China Shanghai Qi Zhi Institute Shanghai 200232China Light Industry Institute of Electrochemical Power Sources Soochow UniversitySuzhou 215006China

In recent years,machine-learning methods have profoundly impacted research in the interdisciplinary fields of ***,most machine-learning models lack interpretability,and physicists doubt the credibility of their conclusions because they cannot be combined with prior physical ***,this review focuses on symbolic regression,which is an interpretable machine-learning ***,the relevant concepts of machine learning are introduced in conjunction with ***,we provide an overview of symbolic regression ***,the recent directions for the application of symbolic regression methods in different subfields of physics are outlined,and an overview of the ways in which the applications of symbolic regression have evolved in the realm of physics is *** major aim of this review is to introduce the basic principles of symbolic regression and explain its applications in the field of physics.

关键词： machine learning genetic programming symbolic regression

Enterogenous infection of Candida albicans in immunocompromised rats under severe acute pancreatitis

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World Journal of Emergency Medicine 2016年第4期7卷 294-299页

作者： Xiang-wang Zhao Lei Yan Dan Xu Yu-hui Cui Chun-hui Yang Yan-jun Zhou jian-guo tang Department of Intensive Care Unit Shandong Cancer HospitalShandong UniversityJinan 250117China Department of Emergency Medicine Zhongshan HospitalFudan UniversityShanghai 200032China Department of Trauma-Emergency&Critical Care Medicine Shanghai Fifth People's HospitalFudan University Shanghai 200240China Division of Swine Infectious Diseases Shanghai Veterinary Research InstituteCAASShanghai 200240China

BACKGROUND:Opportunistic infection of Candida albicans(***) has become a serious problem in immunocompromised *** study aimed to explore the mechanism of enterogenous infection of *** in immunocompromised rats under severe acute pancreatitis(SAP).METHODS:Sprague Dawley(SD) rats(n=100) were randomly assigned into 5 groups as the following:blank group,cyclophosphamide+ceftriaxone+SAP group,cyclophosphamide+ceftriaxone group,cyclophosphamide+SAP group,and cyclophosphamide *** rats were sacrificed at 5and 10 days,and their jejunum,colon,mesenteric lymph nodes,pancreas,intestinal content,and blood were quickly collected to detect ***.A region of the 25 S rRNA gene was chosen and amplified by polymerase chain reaction(PCR) to differentiate *** *** amplified products were further sequenced and compared to judge their ***:Compared with the Cyclophosphamide group,the combination of immunosuppressants and broad-spectrum antibiotics significantly increased the colonization of *** in intestine in 5 and 10 *** SAP stress did not increase the opportunistic infection of *** PCR products of *** isolates all belonged to the genotype A family,and sequence alignment showed that the amplified fragments were ***:The damage of immune system and broad-spectrum antimicrobial agents are important risk factors for opportunistic fungal *** tract is an important source for genotype-A *** to translocate and invade into bloodstream.

关键词： Candida albicans Immunosuppression Severe acute pancreatitis Genotype

solated Unilateral Horizontal Semicircular Cana Malformation

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Chinese Medical Journal 2018年第6期131卷 743-745页

作者： Yi-Wei Liu Ke Sun jian-guo tang Department of Otolaryngology-Head and Neck Surgery Sir Run Run Shaw Hospital Medical College of Zhejiang University Hangzhou Zhejiang 310016 China

To the Editor： Semicircular canal （SCC） malformation （dystrophy, coloboma, or enlargement） is a kind of inner ear anomaly. It is usually found in congenital syndromes along with the malformation（s） of other structure（s） of any of the parts of the ear including the inner ear. Isolated one SCC malformation is extremely rare and might thereby be easily missed. The present study reports a case of the left lateral SCC （LSCC） aplasia.

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The Structure Entropy of Social Networks

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Journal of Systems Science & Complexity 2024年第3期37卷 1147-1162页

作者： LI Zhenpeng YAN Zhihua YANG jian tang Xijin School of Electronics and Information Engineering Taizhou UniversityLinhai 317000China Academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing 100190China Yunnan Key Laboratory of Smart City in Cyberspace Security Yuxi Normal UniversityYuci 653100China University of Chinese Academy of Sciences Beijing 100039China

Micro triadic structure is an important motif and serves the building block of complex *** this paper,the authors define structure entropy for a social network and explain this concept by using the coded triads proposed by Davis and Leinhardt in *** proposed structure entropy serves as a new macro-evolution index to measure the network’s stability at a given *** analysis of real-world network structure entropy discloses rich information on the mechanism that yields given triadic motifs frequency *** paper illustrates the intrinsic link between the micro dyadic/triadic motifs and network structure ***,the authors find that the high proportion of reciprocity and transitivity results in the emergence of hierarchy,order,and cooperation of online social networks.

关键词： Dyadic and triadic motifs network structure entropy reciprocity and transitivity

Covering-Based Soft Rough Sets

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Journal of Electronic Science and Technology 2011年第2期9卷 118-123页

作者： jian-guo tang Kun She Yu-Qi Wang School of Computer Science and Engineering University of Electronic Science and Technology of ChinaChengdu 611731China School of Computer Science and Engineering Xinjiang University of Finance and EconomicsUrumqi 830012China Key Lab of Granular Computing Zhangzhou Normal UniversityZhangzhou 363000China

Covering-based rough sets process data organized by a covering of the universe. A soft set is a parameterized family of subsets of the universe. Both theories can deal with the uncertainties of data. Soft sets have not any restrictions on the approximate description of the object,and they might form a covering of the universe. From this viewpoint,we establish a connection between these two theories. Specifically,we propose a complementary parameter for this purpose. With this parameter,the soft covering approximation space is established and the two theories are bridged. Furthermore,we study some relations between the covering and the soft covering approximation space and obtain some significant results. Finally,we define a notion of combine parameter which can help us to simplify the set of parameters and reduce the storage requirement of a soft covering approximation space.

关键词： Complementary parameter covering-based rough sets covering-element soft set

Research progress on metal-organic framework compounds(MOFs)in electrocatalysis

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Journal of Environmental Sciences 2024年第7期141卷 261-276页

作者： Yutong guo Shunzheng Zhao Xiaolong tang Honghong Yi Department of Environmental Science and Engineering School of Energy and Environmental EngineeringUniversity of Science and Technology BeijingBeijing 100083China Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants Beijing 100083China

Metal-organic frameworks(MOFs)have favorable characteristics such as large specific surface area,high porosity,structural diversity,and pore surface modification,giving them great potential for development and attractive prospects in the research area of modern materials ***,unsatisfactory catalytic activity and poor electronic conductivity are the main challenges facing *** review focuses on MOF-based materials used in electrocatalysis,based on the types of catalytic reactions that have used MOF-based materials in recent years along with their applications,and also looks at some new electrocatalytic materials and their future development prospects.

关键词： Metal-organic frame compounds Electrocatalysis Oxidation-reduction Nitrogen fixation to synthesize ammonia Carbon dioxide reduction