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IEEE Conference on Aerospace

作者： Eric Sholes Aviation and Missile Research Development and Engineering Center System Simulation Development Directorate Redstone Arsenal AL USA

At PerMIS 2002, the Air Force research Lab presented a paper entitled "Metrics Schmetrics", which presented the results of a research study on how to determine the autonomy level of a unmanned aerial vehicle (UAV). The striking point made by the author, given the obvious importance of the need to effectively evaluate and classify autonomous algorithms, was the general dearth of existing effective metrics and/or taxonomies to determine a UAVs autonomy level. To fill the void, the author presented a framework, referred to as the AFRL Autonomy Framework, which identified 10 autonomy control levels (ACLs) and presented the characteristics that differentiate the various levels. The purpose of this paper is to examine how the metrics presented have been applied and how they have evolved and expanded, in theory and practice, as a result of lessons learned during those applications. Specifically, the evolution in metrics development has culminated with the advent of an evaluation technique that blends emerging simulation technologies to create new unmanned aerial vehicle (UAV) autonomy assessment methods which take full advantage of visual virtual environments and statistical constructive simulations to examine the autonomy algorithm along the four dimensions of the Observe, Orient, Decide, Act (OODA) loop commonly applied by military aviators during the decision making process. This approach has been used over the last three years to evaluate emerging autonomy technologies from the Army's Unmanned Autonomous Collaborative Operations (UACO) Science and technology program. This unique technique for testing UAV autonomy effectiveness is a significant advance in the UAV community. As autonomy algorithms proliferate to the point where multiple candidate algorithms are available for each platform, the ability to characterize the effectiveness of each autonomy algorithm will be critical to further for successful implementation of autonomous capability.

关键词： Unmanned aerial vehicles Taxonomy Missiles Virtual environment Decision making Automotive engineering systems engineering and theory Collaboration Testing Aerospace industry

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Explicit Multi-Symplectic Splitting Methods for the Nonlinear Dirac Equation

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Advances in Applied Mathematics and Mechanics 2014年第4期6卷 494-514页

作者： Yaming Chen Songhe Song Huajun Zhu Department of Mathematics and System Science and State Key Laboratory of High Performance Computing National University of Defense TechnologyChangsha 410073China State Key Laboratory of Aerodynamics China Aerodynamics Research and Development CenterMianyang 621000China

In this paper,we propose two new explicit multi-symplectic splitting methods for the nonlinear Dirac(NLD)*** on its multi-symplectic formulation,the NLD equation is split into one linear multi-symplectic system and one nonlinear infinite Hamiltonian *** multi-symplectic Fourier pseudospectral method and multi-symplectic Preissmann scheme are employed to discretize the linear subproblem,*** the nonlinear subsystem is solved by a symplectic ***,a composition method is applied to obtain the final schemes for the NLD *** find that the two proposed schemes preserve the total symplecticity and can be solved *** experiments are presented to show the effectiveness of the proposed methods.

关键词： Nonlinear Dirac equation multi-symplectic method splitting method explicit method

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Application of readiness approach to risk management for materiel life cycle

Application of readiness approach to risk management for mat...

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5th IEEE International Conference on Management of Innovation and technology, ICMIT2010

作者： Zhao, G. Zhao, G.Y. Zhao, T.D. Xing, C.G. School of Reliability and System Engineering Beijing University of Aeronautics and Astronautics Beijing China Aeronautical Technology Research Division Aviation Industry Development Research Center of China Beijing China

ISBN: (纸本)9781424465675

In order to reduce the risks for materiel development effectively, technology readiness is always highlighted during materiel acquisition. This paper discusses readiness assessment method based on technology readiness and applies the method to risk management for materiel development. This paper introduces readiness and readiness-related concepts and describes several popular readiness models, discusses the process of risk management, and then puts forward the method for applying readiness assessment to risk management and gives the thought and flow of such application. © 2010 IEEE.

关键词： Risk assessment

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High-resolution and site-specific SSRM on S/D engineering

High-resolution and site-specific SSRM on S/D engineering

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10th International Workshop on Junction technology, IWJT-2010

作者： Zhang, L. Saitoh, M. Koike, M. Takeno, S. Tanimoto, H. Adachi, K. Yasutake, N. Kusunoki, N. Advanced LSI Technology Laboratory Corporate Research and Development Center Toshiba Corporation Japan Center for Semiconductor Research and Development Japan System LSI Division Semiconductor Company 1 Komukai-Toshiba-Cho Saiwai-Ku Kawasaki 212-8582 Japan

ISBN: (纸本)9781424458691

Recently, we reported significantly improved spatial resolution in scanning spreading resistance microscopy (SSRM) by measuring in a vacuum. In this work, we demonstrate the 1-nm-spatial resolution of SSRM on pn junction delineation by comparing with three-dimensional device simulation. A five-order dynamic range of carrier concentration is also confirmed on staircase sample. A systematic comparison between pFETs/nFETs on (110) and (100) substrates has been carried out with SSRM. The S/D of (110) pFETs shows less lateral distribution than that of (100), strongly indicating 2D-channeling effect of boron ion implantation. We also succeeded in a new sample-making method by fully FIB pick up, enabling site-specific SSRM characteristics for failure analysis and for further scaled devices. © 2010 IEEE.

关键词： Carrier concentration

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Effects of climate,land use and land cover changes on soil loss in the Three Gorges Reservoir area,China

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Geography and Sustainability 2020年第3期1卷 200-208页

作者： Chunbo Huang Zhixiang Zhou Mingjun Teng Changguang Wu Pengcheng Wang Research Center for Spatial Planning and Human-Environment System Simulation School of Geography and Information EngineeringChina University of GeosciencesWuhan 430078China College of Horticulture and Forestry Sciences/Hubei Engineering Technology Research Center for Forestry Information Huazhong Agricultural UniversityWuhan 430070China

Climate,land use and land cover(LULC)changes are among the primary driving forces of soil *** their effects can help in understanding the magnitude and trend of soil loss in response to human activities and ecosystem ***,the RUSLE model was applied to estimate the spatial-temporal variations of soil loss rate in the Three Gorges Reservoir(TGR)area during 2001-2015,followed by a scenario design to decouple the effects of climate and LULC *** results showed that increasing rainfall generated as much as 2.90×10^(7)t soil loss in the TGR ***,such effect was offset by changes in LULC particularly afforestation,which retained about 1.10×10^(7)t soil *** human activities such as dam development and urbanization aggravated soil loss by as much as 1.40×10^(6)t *** of land use policies that favor economic development,distinct spatial variances of soil loss were observed in TGR *** loss in some counties located downstream of the TGR area(i.e.,close to the dam)was more influenced by dam development,but soil loss in the other counties was more influenced by *** climate change(i.e.,increasing rainfall)did not affect plant performance in TGR area,our findings suggested that ecological restoration was more beneficial to curb the amount of soil loss caused by urbanization and dam construction.

关键词： Water erosion Ecosystem service Relative contribution Scenario design Spatial heterogeneity

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Reduced switching loss based cell capacitor voltage balancing strategy for MMC 9

Reduced switching loss based cell capacitor voltage balancin...

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9th IEEE International Conference on Power Electronics, Drives and Energy systems, PEDES 2020

作者： Choudhury, Abhijit Shimada, Takae Kanouda, Akihiko Mabuchi, Yuuichi Center for Technology Innovation-Controls Hitachi Ltd. Research and Development Group Drive System Control Research Department Hitachi-shi Ibaraki-ken319-1292 Japan

ISBN: (纸本)9781728156729

Modular multilevel converter (MMC) is considered to be an efficient solution for high voltage and high power applications, like for high voltage DC transmission (HVDC) system. This is due to their inherent modular structure, usage of low voltage power devices, inherent distributed energy storage capability for each cell unit and the absence of DC link capacitor. Due to their above-mentioned advantages they are considered to be a suitable candidate for medium voltage and medium power « 500 kW) application like for energy storage and DC microgrid applications as well. However, MMC has an inherent problem of cell capacitor voltage imbalance. To solve this issue a reduced switching loss-based cell capacitor voltage balancing strategy is proposed. The proposed strategy is based on the conventional sorting algorithm, which helps to reduce the switching losses considerably while maintaining the set capacitor voltage ripple. Detailed analytical analysis and simulation studies are carried out to show the efficacy of the proposed system for a 300 kVA system. Results show a considerable reduction in the total converter losses (40%) compared to the conventional scheme. © 2020 IEEE.

关键词： Cells

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Towards Cost-Effective Cloud Downloading with Tencent Big Data

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Journal of Computer Science & technology 2015年第6期30卷 1163-1174页

作者：李振华刘刚嵇智源 Roger Zimmermann School of Software Tsinghua University Beijing 100084 China Tsinghua National Laboratory for Information Science and Technology Beijing 100084 China QQXuanfeng System Group Tencent Co. Ltd Shanghai 200233 China High Technology Research and Development Center Ministry of Science and Technology Beijing 10004 China Department of Computer Science National University of Singapore Singapore 117417 Singapore

The cloud downloading scheme, first proposed by us in 2011, has effectively optimized hundreds of millions of users＇ downloading experiences. Also, people start to build a variety of useful Internet services on top of cloud downloading. In brief, by using cloud facilities to download （and cache） the requested file from the ＂best-effort＂ Internet on behalf of the user, cloud downloading ensures the data availability and remarkably enhances the data delivery speed. Although this scheme seems simple and straightforward, designing a real-world cloud downloading system involves complicated and subtle trade-offs （between deployment cost and user experience） when serving a large number of users： 1） how to plan the cloud cache capacity to achieve a high and affordable cache hit ratio, 2） how to accelerate the data delivery from the cloud to numerous users, 3） how to handle the dense user requests for highly popular files, and 4） how to judge a potential downloading failure of the cloud. This paper addresses these design trade-offs from a practical perspective, based on big data from a nationwide commercial cloud downloading system, i.e., Tencent QQXuanfeng. Its running traces help us find reasonable design strategies and parameters, and its real performances confirm the efficacy of our design. Our study provides solid experiences and valuable heuristics for the developers of similar and relevant systems.

关键词： cloud downloading cost-effective design trade-off big data

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TV guidance technical schemes for manned lunar soft landing 7

TV guidance technical schemes for manned lunar soft landing

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7th IEEE Chinese Guidance, Navigation and Control Conference, CGNCC 2016

作者： Xibao, Xu Jifeng, Guo Chengchao, Bai Luwen, Zhang School of Astronautics Harbin Institute of Technology Harbin150001 China Beijing Institute of Astronautical Systems Engineering Beijing100076 China Aircraft System Simulation Research Center Harbin Institute of Technology Harbin150001 China

ISBN: (纸本)9781467383189

This paper researches the manually controlled site reselection focusing on the approaching phase and landing phase of soft landing of manned lunar landing. First, this paper introduces the phase division of manned lunar landing, establishes the kinetic model for lunar module and then makes research on the manual control site selection scheme under TV guidance. In the TV guidance scheme, the astronaut can directly select new lunar landing point within the field of view. The target guidance is achieved by automatic control system. Meanwhile, the impact of response delay of the astronaut on tasks in actual execution is considered. According to the simulation results of the guidance scheme, as the TV guidance is not restricted by the angle of sight, the adjustable range of the landing point is relatively great. Meanwhile, TV guidance has relatively great requirements on the attitude maneuver. In addition, the earlier the site reselection made by the astronaut, the greater the adjustable range of the landing point is. © 2016 IEEE.

关键词： Automation

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Performance Analysis of 3D-IC for Multi-Core Processors in sub-65nm CMOS technologies

Performance Analysis of 3D-IC for Multi-Core Processors in s...

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International Symposium on Circuits and systems Nano-Bio Circuit Fabrics and systems (ISCAS 2010)

作者： Nomura, Kumiko Abe, Keiko Fujita, Shinobu Kurosawa, Yasuhiko Kageshima, Atsushi Advanced LSI Technology Laboratory Corporate R and D Center Toshiba Corporation Japan Center of Semiconductor Research and Development Toshiba Semiconductor Company Japan System LSI Division Toshiba Semiconductor Company Japan

ISBN: (纸本)9781424453092

Three-dimensional integrated circuits (3D-IC) have the potential to reduce interconnect length and improve performance especially in sub-65nm CMOS technologies. This paper describes design and performance analysis of the 3D-IC in sub-65nm CMOS technologies based on the accurate calculation of interconnects delays using 16-core processors as case studies. Performance improvement of the 3D-IC vs. 2D-IC is increased as CMOS scales down, which is consistent with the expected trend. The performance improvement is over 20%. Furthermore, performance of the 3D-IC in 65 nm (or 45 nm) CMOS technology is superior to that of the 2D-IC in 45 nm (or 32 nm) CMOS technology. It indicates that design conversion from 2D-IC to 3D-IC is superior to the CMOS technology migration according to COMS scaling. Reduction in repeater buffers and area overhead is also estimated.

关键词： CMOS integrated circuits

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A Client Selection Method Based on Loss Function Optimization for Federated Learning

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Computer Modeling in Engineering & Sciences 2023年第10期137卷 1047-1064页

作者： Yan Zeng Siyuan Teng Tian Xiang Jilin Zhang Yuankai Mu Yongjian Ren Jian Wan School of Computer Science and Technology Hangzhou Dianzi UniversityHangzhou310018China Key Laboratory of Complex System Modeling and Simulation Ministry of EducationHangzhou310018China Zhejiang Engineering Research Center of Data Security Governance Hangzhou310018China Intelligent Robotics Research Center Zhejiang LabHangzhou311100China HDU-ITMO Joint Institute Hangzhou Dianzi UniversityHangzhou310018China

Federated learning is a distributedmachine learningmethod that can solve the increasingly serious problemof data islands and user data privacy,as it allows training data to be kept locally and not shared with other *** trains a globalmodel by aggregating locally-computedmodels of clients rather than their ***,the divergence of local models caused by data heterogeneity of different clients may lead to slow convergence of the global *** this problem,we focus on the client selection with federated learning,which can affect the convergence performance of the global model with the selected local *** propose FedChoice,a client selection method based on loss function optimization,to select appropriate local models to improve the convergence of the global *** firstly sets selected probability for clients with the value of loss function,and the client with high loss will be set higher selected probability,which can make them more likely to participate in ***,it introduces a local control vector and a global control vector to predict the local gradient direction and global gradient direction,respectively,and calculates the gradient correction vector to correct the gradient direction to reduce the cumulative deviationof the local gradient causedby *** experiments to verify the validity of FedChoice on CIFAR-10,CINIC-10,MNIST,EMNITS,and FEMNIST datasets,and the results show that the convergence of FedChoice is significantly improved,compared with FedAvg,FedProx,and FedNova.

关键词： Federated learning model aggregation Non-IID

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