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High-pressure minerals and new lunar mineral changesite-(Y) in Chang’e-5 regolith

Matter and Radiation at Extremes 2024年第2期9卷 90-97页

作者： Jing yang Wei Du Center for Lunar and Planetary Sciences Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China State Key Laboratory of Ore Deposit Geochemistry Institute of GeochemistryChinese Academy of Sciences(CAS)Guiyang 550081China CAS Center for Excellence in Comparative Planetology Hefei 230026China

Forty-five years after the Apollo and Luna missions, China’s Chang’e-5 (CE-5) mission collected ∼1.73 kg of new lunar materials from one ofthe youngest basalt units on the Moon. The CE-5 lunar samples provide opportunities to address some key scientific questions related to theMoon, including the discovery of high-pressure silica polymorphs (seifertite and stishovite) and a new lunar mineral, changesite-(Y). Seifertitewas found to be coexist with stishovite in a silica fragment from CE-5 lunar regolith. This is the first confirmed seifertite in returned lunarsamples. Seifertite has two space group symmetries (Pnc2 and Pbcn) and formed from an α-cristobalite-like phase during “cold” compressionduring a shock event. The aftershock heating process changes some seifertite to stishovite. Thus, this silica fragment records different stagesof an impact process, and the peak shock pressure is estimated to be ∼11 to 40 GPa, which is much lower than the pressure condition forcoexistence of seifertite and stishovite on the phase diagram. Changesite-(Y), with ideal formula (Ca_(8)Y)◻Fe^(2+)(PO_(4))_(7) (where ◻ denotes avacancy) is the first new lunar mineral to be discovered in CE-5 regolith samples. This newly identified phosphate mineral is in the form ofcolumnar crystals and was found in CE-5 basalt fragments. It contains high concentrations of Y and rare earth elements (REE), reaching upto ∼14 wt. % (Y,REE)2O3. The occurrence of changesite-(Y) marks the late-stage fractional crystallization processes of CE-5 basalts combinedwith silicate liquid immiscibility. These new findings demonstrate the significance of studies on high-pressure minerals in lunar materials andthe special nature of lunar magmatic evolution.

关键词： evolution minerals basalt

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An improved initial rotor position estimation method using high-frequency pulsating voltage injection for PMSM

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Defence Technology（防务技术） 2024年第3期33卷 19-29页

作者： yang Jiang Ming Cheng School of Electrical Engineering Southeast UniversityNanjing 210096China

High frequency pulsating voltage injection method is a good candidate for detecting the initial rotor position of permanent magnet synchronous ***,traditional methods require a large number of filters,which leads to the deterioration of system stability and dynamic *** order to solve these problems,a new signal demodulation method is proposed in this *** proposed new method can directly obtain the amplitude of high-frequency current,thus eliminating the use of filters,improving system stability and dynamic performance and saving the work of adjusting filter *** addition,a new magnetic polarity detection method is proposed,which is robust to current measurement ***,experiments verify the effectiveness of the method.

关键词： Initial position detection Signal demodulation algorithm Magnetic polarity detection Filter elimination

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Large language model and domain-specific model collaboration for smart education

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Frontiers of Information Technology & Electronic Engineering 2024年第3期25卷 333-341页

作者： Yawei LUO Yi yang School of Software Technology Zhejiang UniversityNingbo 315048China College of Computer Science and Technology Zhejiang UniversityHangzhou 310027China

In this paper,we introduce the large language model and domain-specific model collaboration(LDMC)framework designed to enhance smart *** LDMC framework leverages the comprehensive and versatile knowledge of large domain-general models,combines it with the specialized and disciplinary knowledge from small domainspecific models(DSMs),and incorporates pedagogy knowledge from learning theory *** integration yields multiple knowledge representations,fostering personalized and adaptive educational *** explore various applications of the LDMC framework in the context of smart education.

关键词： smart language knowledge

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Expert consensus on pediatric orthodontic therapies of malocclusions in children

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International Journal of Oral Science 2024年第2期16卷 186-196页

作者： Chenchen Zhou Peipei Duan Hong He Jinlin Song Min Hu yuehua Liu Yan Liu Jie Guo Fang Jin yang Cao Lingyong Jiang Qingsong Ye Min Zhu Beizhan Jiang Wenhua Ruan Xiao Yuan Huang Li Rui Zou Yulou Tian Li Gao Rui Shu Jianwei Chen Renkai Liu Shujuan Zou Xiaobing Li State Key Laboratory of Oral Diseases&National Center for Stomatology&National Clinical Research Center for Oral Diseases&Department of Pediatric Dentistry West China Hospital of StomatologySichuan UniversityChengduChina State Key Laboratory of Oral Diseases&National Center for Stomatology&National Clinical Research Center for Oral Diseases&Department of Orthodontics West China Hospital of StomatologySichuan UniversityChengduChina State Key Laboratory of Oral and Maxillofacial Reconstruction and Regeneration&Key Laboratory of Oral Biomedicine Ministry of Education&Hubei Key Laboratory of Stomatology&Department of Orthodontics&Center for Dentofacial Development and Sleep Medicine School and Hospital of StomatologyWuhan UniversityWuhanChina Chongqing Key Laboratory of Oral Diseases and Biomedical Sciences&Chongqing Municipal Key Laboratory of Oral Biomedical Engineering of Higher Education Stomatological Hospital of Chongqing Medical UniversityChongqing Medical University&College of StomatologyChongqing Medical UniversityChongqingChina Department of Orthodontics Hospital of StomatologyJilin UniversityChangchunChina Department of Orthodontic&Oral Biomedical Engineering Laboratory Shanghai Stomatological HospitalFudan UniversityShanghaiChina Department of Orthodontics Central LaboratoryPeking University School and Hospital for Stomatology&National Center for Stomatology&National Clinical Research Center for Oral Diseases&National Engineering Research Center of Oral Biomaterials and Digital Medical Devices&Beijing Key Laboratory of Digital Stomatology&Research Center of Engineering and Technology for Computerized Dentistry Ministry of Health&NMPA Key Laboratory for Dental Materials&National Engineering Research Center of Oral Biomaterials and Digital Medical DevicesBeijingChina Department of Orthodontics School and Hospital of StomatologyCollege of MedicineShandong University&Shandong Key Laboratory of Oral Tissue Regeneration&Shandong Engineering Laboratory for Dental Materials and Oral Tissue

Malocclusion,identified by the World Health Organization(WHO)as one of three major oral diseases,profoundly impacts the dental-maxillofacial functions,facial esthetics,and long-term development of~260 million children in *** its physical manifestations,malocclusion also significantly influences the psycho-social well-being of these *** intervention in malocclusion can foster an environment conducive to dental-maxillofacial development and substantially decrease the incidence of malocclusion or reduce the severity and complexity of malocclusion in the permanent dentition,by mitigating the negative impact of abnormal environmental influences on the *** orthodontic treatment encompasses accurate identification and treatment of dental and maxillofacial morphological and functional abnormalities during various stages of dental-maxillofacial development,ranging from fetal stages to the early permanent dentition *** an economic and societal standpoint,the urgency for effective early orthodontic treatments for malocclusions in childhood cannot be overstated,underlining its profound practical and social *** consensus paper discusses the characteristics and the detrimental effects of malocclusion in children,emphasizing critical need for early *** elaborates on corresponding core principles and fundamental approaches in early orthodontics,proposing comprehensive guidance for preventive and interceptive orthodontic treatment,serving as a reference for clinicians engaged in early orthodontic treatment.

关键词： permanent stated children

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Game-theoretical Model for Dynamic Defense Resource Allocation in Cyber-physical Power Systems Under Distributed Denial of Service Attacks

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Journal of Modern Power Systems and Clean Energy 2024年第1期12卷 41-51页

作者： Bingjing Yan Pengchao Yao Tao yang Boyang Zhou Qiang yang the College of Electrical Engineering Zhejiang UniversityHangzhou 310027China Zhejiang Lab Hangzhou 311100China

Electric power grids are evolving into complex cyber-physical power systems(CPPSs)that integrate advanced information and communication technologies(ICTs)but face increasing cyberspace threats and *** study considers CPPS cyberspace security under distributed denial of service(DDoS)attacks and proposes a nonzero-sum game-theoretical model with incomplete information for appropriate allocation of defense resources based on the availability of limited *** time delay is applied to quantify the expected utility as CPPSs have high time requirements and incur massive damage DDoS *** resource allocation strategies are adopted by attackers and defenders under the three cases of attack-free,failed attack,and successful attack,which lead to a corresponding consumption of resources.A multidimensional node value analysis is designed to introduce physical and cybersecurity *** experiments and numerical results demonstrate the effectiveness of the proposed model for the appropriate allocation of defense resources in CPPSs under limited resource availability.

关键词： Game theory complex cyber-physical power system(CPPS) multidimensional evaluation distributed denial of service(DDoS)attack

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An anti-collision algorithm for robotic search-and-rescue tasks in unknown dynamic environments

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Frontiers of Information Technology & Electronic Engineering 2024年第4期25卷 569-584页

作者： yang CHEN Dianxi SHI Huanhuan yang Tongyue LI Zhen WANG School of Computer Science Peking UniversityBeijing 100871China Tianjin Artificial Intelligence Innovation Center Tianjin 300457China Intelligent Game and Decision Lab Beijing 100071China College of Computer National University of Defense TechnologyChangsha 410073China

This paper deals with the search-and-rescue tasks of a mobile robot with multiple interesting targets in an unknown dynamic *** problem is challenging because the mobile robot needs to search for multiple targets while avoiding obstacles *** ensure that the mobile robot avoids obstacles properly,we propose a mixed-strategy Nash equilibrium based Dyna-Q(MNDQ)***,a multi-objective layered structure is introduced to simplify the representation of multiple objectives and reduce computational *** structure divides the overall task into subtasks,including searching for targets and avoiding ***,a risk-monitoring mechanism is proposed based on the relative positions of dynamic *** mechanism helps the robot avoid potential collisions and unnecessary ***,to improve sampling efficiency,MNDQ is presented,which combines Dyna-Q and mixed-strategy Nash *** using mixed-strategy Nash equilibrium,the agent makes decisions in the form of probabilities,maximizing the expected rewards and improving the overall performance of the Dyna-Q ***,a series of simulations are conducted to verify the effectiveness of the proposed *** results show that MNDQ performs well and exhibits robustness,providing a competitive solution for future autonomous robot navigation tasks.

关键词： Search and rescue Reinforcement learning Game theory Collision avoidance Decision-making

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High-Superelasticity NiTi Shape Memory Alloy by Directed Energy Deposition-Arc and Solution Heat Treatment

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Acta Metallurgica Sinica(English Letters) 2024年第1期37卷 132-144页

作者： Junyi Ma Lin Yu Qing yang Jie Liu Lei yang State Key Laboratory of Materials Processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan430070China School of Transportation and Logistics Engineering Wuhan University of TechnologyWuhan430074China

Directed energy deposition-arc(DED-Arc)technology has the advantages of simple equipment,low manufacturing cost and high deposition rate,while the use of DED-Arc has problems of microstructure inhomogeneity,position dependence of macroscopic mechanical properties and ***,it is necessary to carry out a subsequent heat treatment to improve its microstructure uniformity,mechanical properties and *** this investigation,the DED-Arc 15-layer NiTi alloy thin-walled parts with the solution treatment at different process parameters were studied to analyze the effects of solution heat treatment on microstructure,phase composition,phase transformation,microhardness,tensile and *** temperature range of solution treatment is 800-1050℃,and the treatment time range is 1-5.5 *** results show that after solution treatment at 800℃/1 h,the content of precipitated phase decreases,the grain is refined,the microhardness increases,and the mechanical properties in the 0°direction are *** strain recovery rate after 10 tensile cycles has increased from 37.13%(as-built)to 49.25%(solid solution treatment).This research provides an effective post treatment method for high-performance DED-Arc NiTi shape memory alloys.

关键词： Directed energy deposition-arc(DED-Arc) Cold metal transfer(CMT) NiTi shape memory alloys Microstructure Phase transformation Solution heat treatment

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Geometric Constraints for Global Regularity of 3D Shear Thickening Fluids

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Acta Mathematicae Applicatae Sinica 2024年第1期40卷 205-210页

作者： Jia-qi yang Research&Development Institute of Northwestern Polytechnical University in Shenzhen Shenzhen518063China Key Laboratory for Mechanics in Fluid Solid Coupling Systems Institute of MechanicsChinese Academy of SciencesBeijing100190China

We consider the relation between the direction of the vorticity and the global regularity of 3D shear thickening *** is showed that a weak solution to the non-Newtonian incompressible fluid in the whole space is stron... 详细信息

关键词： direction of the vorticity non-Newtonian fluid global regularity

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基于分布式代理的云资源调度中可信数据获取机制(英文)

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China Communications 2011年第6期8卷 108-116页

作者：李小勇杨月华 Beijing Key Lab of Intelligent Telecommunication Software and Multimedia Beijing University of Posts and Telecommunications

Cloud computing is a new paradigm in which dynamic and virtualized computing resources are provided as services over the Internet. However, because cloud resource is open and dynamically configured, resource allocation and scheduling are extremely important challenges in cloud infrastructure. Based on distributed agents, this paper presents trusted data acquisition mechanism for efficient scheduling cloud resources to satisfy various user requests. Our mechanism defines, collects and analyzes multiple key trust targets of cloud service resources based on historical information of servers in a cloud data center. As a result, using our trust computing mechanism, cloud providers can utilize their resources efficiently and also provide highly trusted resources and services to many users.

关键词： cloud computing trusted computing distributed agent resource scheduling

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Anomalous magnetic property and broadband photodetection in ultrathin non-layered manganese selenide semiconductor

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Nano Research 2024年第9期17卷 8578-8584页

作者： Ye Zhao Ruilong yang Ke yang Jiarui Dou Xiaoting yang Jinzhong Guo Guowei Zhou Xiaohong Xu School of Chemistry and Materials Science Key Laboratory of Magnetic Molecules and Magnetic Information Materials of Ministry of EducationShanxi Normal UniversityTaiyuan 030006China Research Institute of Materials Science Collaborative Innovation Center for Shanxi Advanced Permanent Magnetic Materials and TechonologyShanxi Normal UniversityTaiyuan 030006China

Two-dimensional(2D)semiconductors with intrinsic ferromagnetism are highly desirable for potential applications in nextgeneration spintronic and optoelectronic ***,controllable synthesis of intrinsic 2D magnetic semiconductor on a substrate is still a challenging ***,large-area 2D non-layered rock salt(α-phase)MnSe nanosheets were grown on mica substrates,with the thickness changing from 54.2 to 0.9 nm(one unit cell),by chemical vapour *** X-ray diffraction,Raman spectroscopy,transmission electron microscopy,and X-ray photoelectron spectroscopy measurements confirmed that the resulting 2Dα-MnSe nanosheets were obtained as high-quality single *** magnetic hysteresis loops and synchrotron X-ray measurements directly indicated the anomalous magnetic properties inα-MnSe *** analysis of the reasons for magnetic property revealed that the low-temperature phase transition,small number of stacking differences in crystals,and surface weak oxidation in(111)-orientedα-MnSe were the main ***,α-MnSe nanosheets exhibited broadband photoresponse from 457 to 671 nm with an outstanding detectivity and responsivity *** study presents the detailed growth process of ultrathin 2D magnetic semiconductorα-MnSe,and its outstanding magnetic properties and broadband photodetection,which provide an excellent platform for magneto-optical and magneto-optoelectronic research.

关键词： two-dimensional material anomalous magnetism broadband photodetection α-phase MnSe non-layered crystal

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