检索结果-内蒙古大学图书馆

Machine Learning and Natural Language Processing (MLNLP), International Conference on

作者： Liu Xue Liu Jie Zhu Peipei Xiang Tao National Key Laboratory of Complex Aviation System Simulation Southwest China Institute of Electronic Technology Chengdu China

ISBN: (数字)9798350354973

ISBN: (纸本)9798350354980

To offer the military personnel a good service of assisting them to get information about enemy's equipment outside Internet, we build a system named MilChat which includes a large language model that has the ability to generate texts and an application which is easy to use. The model of MilChat is fine-tuned by the method of LoRA with military datasets from the basic model, Qwen-7B-Chat which is opensource and has good performance. After fine-tuning, the new model has higher scores than the basic one. Besides, we use the method of Prompt Learning to limit the answers into a standard format. Therefore, it is more accurate and professional than the basic model. This study has also a value of industrial application.

关键词： Accuracy Large language models Machine learning Natural language processing Libraries Internet Personnel Standards Military equipment

来源：评论

学校读者我要写书评

暂无评论

Evolution of superconductivity and corresponding electronic structure in pressurized Nb_(3)Sn

引用

Superconductivity 2025年第1期13卷 17-22页

作者： Wenxuan Chen Xintian Chen Yangfan Gao Yazhou Zhou Shu Cai Jinyu Zhao Ke Yang Aiguo Li Sheng Jiang Qi Wu Defang Duan Jing Guo Liling Sun Institute of Physics Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Center for High Pressure Science&Technology Advanced Research Beijing 100094China Shanghai Synchrotron Radiation Facilities Shanghai Advanced Research InstituteChinese Academy of SciencesNo.239 Zhangheng RoadShanghai 201204China Key Laboratory of Material Simulation Methods&Software of Ministry of Education and State Key Laboratory of Superhard Materials College of physicsJilin University130012ChangchunChina

The studies on superconductors under extreme conditions offer valuable insights for assessing their potential in new ***_(3)Sn,an intermetallic alloy with an A15 structure,is a key commercial superconductor known for its high critical current and magnetic field ***,we systematically investigated the physical properties of Nb_(3)Sn under high *** findings reveal that superconductivity in Nb_(3)Sn remains robust up to∼142 GPa,demonstrating remarkable stability despite a gradual suppression of��c with increasing ***-principles calculations indicate that the pressure-dependent superconducting behavior is primarily driven by variations in the density of states of Nb’s d-electrons,particularly contributions from the d_(x^(2)-y^(2)) and d_(z^(2)) ***,we predict the potential for synthesizing Nb_(3)Sn films and demonstrate that biaxial strain induced by suitable substrates can preserve their superconducting *** comprehensive study not only enhances our understanding of Nb_(3)Sn’s superconducting mechanism under high pressure but also opens new avenues for its application in advanced superconducting technologies.

关键词： Superconductivity High pressure Nb_(3)Sn

来源：评论

学校读者我要写书评

暂无评论

Intelligent vehicle path tracking based on feedback linearization and LQR under extreme conditions 41

Intelligent vehicle path tracking based on feedback lineariz...

引用

第41届中国控制会议

作者： Yi Sun Qikun Dai Jun Liu Xu Zhao Hongyan Guo College of Communication Engineering Jilin University The State Key Laboratory of Automotive Simulation and Control Jilin University The Department of Aviation Electrical Engineering Jilin Institute of Chemical Technology

ISBN: (数字)9789887581536

ISBN: (纸本)9781665482561

It proposes a path following control strategy for intelligent vehicles under extreme conditions based on feedback linearization and linear quadratic regulator(LQR).Firstly,the vehicle dynamics model and the vehicle kinematics model are established,and the affine nonlinear vehicle system model under the extreme condition is established by these two ***,the complex nonlinear vehicle system model is linearized using the feedback linearization method to obtain a simpler linear system ***,according to the obtained linear vehicle system model,the LQR method is used to design the tracking controller to obtain the optimal control input,so as to ensure the stability of the system and the optimality of the target,and realize the intelligent vehicle path *** affirm the effectiveness of the tracking method,a series of Carsim/Simulink co-simulation experiments are carried *** results show that the effects of path tracking combined with feedback linearization and LQR are significantly better than the other two methods,thus the path tracking method proposed in the paper is effectively verified.

关键词： Feedback Linearization LQR Affine Nonlinear Vehicle System Model Extreme conditions Path Tracking

来源：评论

学校读者我要写书评

暂无评论

Map of Crystal-Field Effects in Correlated Layered t2gn Perovskites

引用

Physical Review Letters 2024年第23期132卷 236505-236505页

作者： Neda Samani Guoren Zhang Eva Pavarini Institute for Advanced Simulation School of Physics and Technology Key Laboratory of Materials Physics Institute of Solid State Physics Forschungszentrum Jülich Germany

Correlated metallic layered t2gn perovskites are intensively studied and yet their low-energy electronic properties remain hotly debated. Important elements of the puzzle, beside the on-site Coulomb repulsion, are the tetragonal crystal-field splitting and the spin-orbit interaction. Here, we show that they control the electronic properties principally via form and occupations of natural orbitals. We discuss consequences for shape and topology of the Fermi surface, effective masses, and metal-insulator transition, building a map of crystal-field effects. The emerging picture captures electronic-structure trends in this family of systems within a single framework.

关键词： Metal-insulator transition Orbital order Spin-orbit coupling Iridates Layered crystals Mott insulators Perovskites Ruthenates Strongly correlated systems Transition metal oxides Crystal-field theory Dynamical mean field theory

来源：评论

学校读者我要写书评

暂无评论

Research on the Configuration and Capacity Calculation of DC Side Dynamic Braking System 6

Research on the Configuration and Capacity Calculation of DC...

引用

6th International Conference on HVDC, HVDC 2024

作者： Bai, Yu Yang, Yuexi Zhou, Xiao Du, Zhenyu Hu, Yinghong Li, Yu State Grid Smart Grid Research Institute Co. Ltd. National Key Laboratory of Advanced Power Transmission Technology Beijing Key Laboratory of Dc Grid Technology and Simulation Beijing China Electric Power Research Institute State Grid JiBei Electric Power Co. Ltd. Beijing China

ISBN: (纸本)9798350387759

The Flexible DC Transmission technology circumvents the limitation of transmission distance caused by the charging power of AC cables. Additionally, it boasts technical advantages such as effectively isolating the interactions between onshore AC power grids and offshore wind farms, providing stable grid-connected voltage for offshore wind farms, and enabling flexible regulation of system operations. These factors make it the preferred technology for transmitting power from remote offshore wind farms. The offshore wind power flexible grid-connected system incorporates a DC-side dynamic braking system, which functions to absorb excess power injected by the wind farm and prevent system overvoltage when the AC main grid malfunctions, leading to the inability of the onshore converter station to deliver rated power. In this paper, the technical route, configuration scheme and capacity demand of DC side dynamic braking systems are studied, and the DC side dynamic braking system configuration scheme applicable to unipolar and bipolar isolated island new energy transmission flexible system is proposed, and the capacity demand of DC side dynamic braking system is analyzed, and the capacity design scheme of DC side dynamic braking system that conforms to the national calibration and meets the demand of system power balancing and fault ride-through and other requirements under the faulty AC system is proposed. The capacity design scheme of energy consuming devices is proposed in compliance with national calibration and can meet the system power balance and fault ride-through requirements in case of AC system failure and other working conditions. © 2024 IEEE.

关键词： capacity requirements DC side dynamic braking systems flexible DC grid layout design offshore wind power

来源：评论

学校读者我要写书评

暂无评论

NWD-YOLOv5: A YOLOv5 Model for Small Target Detection Based on NWD Loss 6

NWD-YOLOv5: A YOLOv5 Model for Small Target Detection Based ...

引用

6th International Conference on Robotics, Intelligent Control and Artificial Intelligence, RICAI 2024

作者： Zhou, Liliang Ran, Huaming Xiong, Rongling Tan, Ruijie National Key Laboratory of Complex Aviation System Simulation Chengdu610036 China 10th Research Institute China Electronics Technology Group Corporation Chengdu610036 China School of Mathematics Southwest Jiaotong University Chengdu611756 China

ISBN: (纸本)9798331541699

Target detection technology is vital in modern social management and urban security, with small target detection—accurately identifying tiny objects in large scenes—posing a key challenge for improving surveillance system accuracy and real-time performance. The YOLO series is still the mainstream target detection model, for the YOLOv5 model, as the IoU metric it adopts still uses the geometrical overlap of the detection frame as the basis of the loss calculation, while the experiments have proved that this metric is unable to effectively utilize the small-scale characteristics of small targets. Therefore, improving the loss metric in the existing framework can help the model to pay more attention to the spatial semantic features of small targets in the image in the training phase of the network, respectively, and thus improve the detection effect. In this paper, we propose the NWDYOLOv5 model, i.e., we introduce the NWD loss that measures the difference in the distribution of the detection frames for the existing target detection framework YOLOv5, which ensures that the loss of the small targets is not neglected in the calculation of the forward propagation loss of the model, and we purposefully modify the structure of the feature extraction network in the original framework by adding a feature extraction layer for the detection of the small targets, which enhances the ability of the model to capture the subtle features thus improving the accuracy of small target detection. Through comparative experiments, we evaluated the detection performance of the original YOLOv5 model, the YOLOv5 model using only the NWD loss, the YOLOv5 model with only the additional small-target detection layer, and the full NWD-YOLOv5 model for small-targeted human bodies on the screened COCO2017 public dataset, respectively. The experimental results show that compared to the original YOLOv5 model, the model with only the NWD loss improves the mAP@.5 metrics on small-target detection by 16.5

关键词： Digital elevation model

来源：评论

学校读者我要写书评

暂无评论

Health benefits from the rapid reduction in ambient exposure to air pollutants after China's clean air actions:progress in efficacy and geographic equality

引用

National Science Review 2024年第2期11卷 103-113页

作者： Tao Xue Ruohan Wang Meng Wang Yanying Wang Dan Tong Xia Meng Conghong Huang Siqi Ai Fangzhou Li Jingyuan Cao Mingkun Tong Xueqiu Ni Hengyi Liu Jianyu Deng Hong Lu Wei Wan Jicheng Gong Shiqiu Zhang Tong Zhu Institute of Reproductive and Child Health National Health Commission Key Laboratory of Reproductive Health/Department of Epidemiology and Biostatistics Ministry of Education Key Laboratory of Epidemiology of Major Diseases(PKU) School of Public Health Peking University Health Science Centre State Environmental Protection Key Laboratory of Atmospheric Exposure and Health Risk Management and Center for Environment and Health Peking University Advanced Institute of Information Technology Peking University Department of Epidemiology and Environmental Health School of Public Health and Health ProfessionsUniversity at Buffalo State Key Joint Laboratory of Environment Simulation and Pollution Control College of Environmental Sciences and EngineeringPeking University Department of Earth System Science Tsinghua University School of Public Health Key Laboratory of Public Health Safety of the Ministry of Education and Key Laboratory of Health Technology Assessment of the Ministry of HealthFudan University College of Land Management Nanjing Agricultural University National&Local Joint Engineering Research Center for Rural Land Resources Use and Consolidation Clean Air Asia

Clean air actions （CAAs） in China have been linked to considerable benefits in public ***,whether the beneficial effects of CAAs are equally distributed geographically is *** high-resolution maps of the distributions of major air pollutants (fine particulate matter[PM2.5]and ozone[O3]) and population,we aimed to track spatiotemporal changes in health impacts from,and geographic inequality embedded in,the reduced exposures to PM2.5and O3from 2013 to *** used a method established by the Global Burden of Diseases *** analyzing the changes in loss of life expectancy（LLE） attributable to PM2.5and O3,we calculated the gain of life expectancy （GLE） to quantify the health benefits of the air-quality ***,we assessed the geographic inequality embedded in the GLE using the Gini index （GI）.Based on risk assessments of PM2.5and O3,during the first stage of CAAs（2013 to 2017）,the mean GLE was 1.87 *** of the sum of the GLE was disproportionally distributed in about one quarter of the population exposed （GI 0.44）.During the second stage of CAAs（2017 to 2020）,the mean GLE increased to 3.94 months and geographic inequality decreased （GI 0.18）.According to our assessments,CAAs were enhanced,from the first to second stages,in terms of not only preventing premature mortality but also ameliorating health *** enhancements were related to increased sensitivity to the health effects of air pollution and synergic control of PM2.5and *** findings will contribute to optimizing future CAAs.

关键词： clean air action public health inequality fine particulate matter ozone

来源：评论

学校读者我要写书评

暂无评论

Effect of Sb-induced oxygen octahedral distortion on piezoelectric performance and thermal stability of Pb(In,Nb)O_(3)-Pb(Hf,Ti)O_(3)ceramics

引用

Journal of Materials Science & technology 2023年第30期161卷 101-110页

作者： Huanli Shi Mo Zhao Dongyan Zhang Zhimin Li Maolin Zhang Jingya Wang Li Jin Yangxi Yan School of Advanced Materials and Nanotechnology Xidian UniversityXi’an 710071China National Ceramic Industry Design Institute of China Quanzhou 362500China Electronic Materials Research Laboratory Key Laboratory of the Ministry of EducationSchool of Electronic Science and EngineeringXi’an Jiaotong UniversityXi’an 710049China State Key Laboratory of Intense Pulsed Radiation Simulation and Effect(Northwest Institute of Nuclear Technology) Xi’an 710024China Shaanxi Applied Physics and Chemistry Research Institute Xi’an 710061China

The combination of excellent thermal stability and outstanding electrical performance is of great sig-nificance for piezoelectric ***,we have prepared 0.11Pb(In_(0.5)Nb_(0.5))O_(3)-0.89Pb(Hf_(0.47)Ti_(0.53))O_(3)-Sb_(2)O_(5)(PIN-PHT-x Sb)ceramics by solid-phase method and investigated the effect of oxygen octahedral lattice distortion on microstructure and macroscopic electrical *** distortion index of oxygen octahedra is studied by Rietveld refinement,showing that optimal octahedral distortion can soften B-O repulsion,disrupt long-range ordered ferroelectric domains,and enhance local heterogeneities,signifi-cantly increasing piezoelectric ***,outstanding thermal stability and ultrahigh piezo-electric response of PIN-PHT-1.2Sb ceramics are realized under the synergistic influence of octahedral distortion,excellent density,and large grain *** with PIN-PHT ceramics,PIN-PHT-1.2Sb ce-ramics exhibit ultrahigh piezoelectric responses(d_(33)=706 pC/N,k_(p)=0.68,ε_(r)=3244),a high Curie temperature(T C)of 300℃,excellent thermal stability,and anti-fatigue properties.

关键词： Oxygen octahedron Piezoelectric response Thermal stability

来源：评论

学校读者我要写书评

暂无评论

Study on frictional behavior of SiC_(f)/SiC composite clad tube clamping condition under nuclear irradiation

引用

Friction 2024年第5期12卷 919-938页

作者： Chenglong XIAO Liangliang SHEN Tianqi ZHU Jianbo TANG Ximing XIE Xinyu FAN Jian XU Zhiying REN School of Mechanical Engineering Zhejiang University of TechnologyHangzhou310023China Engineering Laboratory of Advanced Energy Materials Ningbo Institute of Material Technology and EngineeringChinese Academy of SciencesNingbo315201China State Key Laboratory of Fine Chemicals Liaoning High-Performance Polymer Engineering Research CenterSchool of Chemical EngineeringDalian University of TechnologyDalian116024China School of Mechanical Engineering and Automation Fuzhou UniversityFuzhou350116China School of Computer Science and Technology Shandong UniversityQingdao266237China Aviation Industry Corporation of China Ltd.Beijing100028China

Silicon carbide fiber reinforced silicon carbide matrix(SiC_(f)/SiC)composite is the key cladding material of nuclear fuel,which determines the safety and reliability of nuclear fuel storage and *** replacement of its storage and transportation scenario needs to be completed by the manipulator,but the application of SiC_(f)/SiC wear,fracture,and nuclear leakage in the snatching process of brittle-flexible-rigid contact in the irradiation environment has been seriously restricted due to unclear understanding of the damage ***,the effects of irradiation dose and clamping load on the friction characteristics of the contact interface between SiC_(f)/SiC clad tube are studied in this paper,and the effects of irradiation parameters and clamping force on the static friction coefficient of the contact interface between the clad tube and flexible nitrile are *** on the Greenwood-Williamson tribological model,a numerical model of the shape and structure of the contact micro-convex at the micro-scale of the clamping interface is constructed by introducing the multi-surface integral,and finally verified by *** research results show that there is a unique“Irradiation suppression zone”under the clamping condition of SiC_(f)/SiC cladding tube under the nuclear irradiation environment,and the growth of static friction coefficient slows down until stagnates after irradiation reaches a certain extent(600 kGy),and there will be a decline when the irradiation dose continues to increase,among which the clamping force of 15.2 N within the irradiation interval of 1,000 kGy can meet the safety of nuclear environment *** results of this paper can provide an important theoretical basis and application guidance for the safe operation of SiC_(f)/SiC cladding tubes in the storage and transportation clamping process.

关键词： SiC_(f)/SiC Clad tube nuclear irradiation conditions Greenwood-Williamson tribological model multi-surface integral

来源：评论

学校读者我要写书评

暂无评论

Simultaneously optimizing pore morphology and enhancing mechanical properties of Al-Si alloy composite foams by graphene nanosheets

引用

Journal of Materials Science & technology 2022年第6期101卷 60-70页

作者： Weiting Li Xudong Yang Kunming Yang Chunnian He Junwei Sha Chunsheng Shi Yunhui Mei Jiajun Li Naiqin Zhao Tianjin Key Laboratory of Composite and Functional Materials School of Materials Science and EngineeringTianjin UniversityTianjin 300350China Sino-European Institute of Aviation Engineering Civil Aviation University of ChinaTianjin 300300China Collaborative Innovation Center of Chemical Science and Engineering Tianjin UniversityTianjin 300350China Tianjin Key Laboratory of Advanced Joining Technology School of Materials Science and EngineeringTianjin UniversityTianjin 300350China

The integrity and regularity of pore morphology play an important role in determining the mechanical properties of the metallic foam *** conventional methods on refining pore morphology are mainly focused on the optimization of fabrication techniques,however,they are usually inconvenient and ***,incorporating nano reinforcement is considered to be a suitable way to fabricate metallic composite foams accompanied by optimized pore morphology and enhanced mechanical *** this work,through a facile and rapid powder metallurgy foaming method,the aluminum-silicon(Al-Si)alloy composite foams reinforced by graphene nanosheets(GNSs)are successfully *** microstructure analyses reveal that,for the Al-Si alloy foams incorporating the GNSs(GNSs/Al-Si composite foams),the pore size is transformed to be smaller,the pore size distributions become more homogeneous and the pore shape is also refined to a regular and roundish ***,the shape of Si precipitates is found transforming from an irregular long strip(length of~20μm,width of~5μm)to a fine particle state(diameter of~5μm).Moreover,the compressive testing results show that,the 0.4wt%GNSs/Al-Si composite foams own the optimal compression stress of 11.7±0.5 MPa,plateau stress of 10.0±1.0 MPa and energy absorption capacity of 6.8±0.7 MJ/m^(3),which have improvement of 58.1%,53.8%and 51.1%in comparison with the Al-Si alloy foams counterpart,*** present findings may pave a new way for developing new generation of metallic composite foams that with stable microstructure and excellent mechanical performance.

关键词： Metal matrix composites Aluminum foam Graphene Energy absorption

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：