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WiFace:A Secure GeoSocial Networking system Using Wi-Fi Based Multihop MANET

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ZTE Communications 2011年第1期9卷 27-32页

作者： Lan Zhang Xuan Ding Zhiguo Wan Ming Gu Xiangyang Li Key Laboratory of Information system Security Tsinghua University department of Computer Science Illinois Institute of Technology

A number of mobile Online Social Networking （OSN） services have appeared in the market in recent times. While most mobile systems benefit greatly from cloud services, centralized servers and communications infrastructure is not always available. Nor are location-based services offered to mobile devices without GPS. To take advantage of cloud and to address these problems, a Wi-Fi based multihop networking system called MoNet is proposed. On top of MONET we propose a privacy-aware geosocial networking service called WiFace. Where there is no infrastructure, a distributed content sharing protocol significantly shortens the relay path, reduces conflicts, and improves data availability. Furthermore, a security mechanism is developed to protect privacy. Comprehensive experiments performed on MoNet show that the system is more than sufficient to support social networking and even audio and video applications.

关键词： Wi-Fi social network privacy MANET WiFace

Design of Lead Spectrometer for Spent Fuel Fissile Assay

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Journal of Energy and Power Engineering 2014年第1期8卷 59-64页

作者： Yong Deok Lee Chang Je Park Ho-Dong Kim Kee Chan Song Nonproliferation system Research department Korea Atomic Energy Research Institute Daejeon 305-353 Korea

The design of a lead slowing down spectrometer is being developed at KAERI （Korea Atomic Energy Research Institute） for an analysis of isotopic fissile content in spent and recycled fuel. The lead spectrometer has an advantage to assay fissile content directly from spent fuel. Accurate fissile material data must be fed back to the spent fuel design and management. For reutilization of PWR spent fuel, an isotopic fissile content analysis is required to obtain safety and economics in the fuel cycle. The LSDS （lead slowing down spectrometer） uses the different fission signatures of each fissile with respect to the interrogation neutron energy. Several simulations were done and parameter was obtained for the system working. Energy between 1 keV to 0.1 eV is very sensitive to isotopic fissile material fission with good energy resolution. An external source neutron is necessary to induce enough fissile fission. A neutron production methodology is being developed for cost effectiveness, easy maintenance and high neutron yield rate. The threshold fission detector screens the prompt fast fission neutrons from an intense radiation background. The detection of a fission signature has a direct relationship with the isotopic fissile content.

关键词： Fissile assay lead slowing down spectrometer fission measurement fissile utilization neutron source resolution.

A study of optimal switching problem in limited-cycle with multiple periods

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2010年第12期11卷 933-937页

作者： Jing SUN Hisashi YAMAMOTO Masayuki MATSUI Graduate School of Engineering Nagoya Institute of Technology Gokiso-cho Showa-ku Nagoya Aichi 466-8555 Japan department of system Design Management Systems Engineering Tokyo Metropolitan University 6-6 Asahigaoka Hino Tokyo 191-0065 Japan department of lnformatics Graduate School of lnformatics and Engineering The University of Electro-Communications 1-5-1 Chofugaoka Chofu-shi Tokyo 182-8585 Japan

In a social system or production line,the restrictions of the cost and the due-time exist in each ***,whether these restrictions are satisfied is dependent not only on the risks of this period,but also on the risks generated *** consider controlling the production process by switching the processing rate to a faster one at a given *** paper deals with the optimal switching period to minimize the total expected cost of the production *** first propose the optimal switching period model,and then the mathematic formulation of the total expectation is ***,the policy of optimal switching period is investigated in detail by numerical experiments.

关键词： Limited-cycle problem Multi-period Optimal switching period Production seat system Manufacturing line

A vector quantization algorithm suitable for VLSI implementation

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Progress in Natural Science:Materials International 1997年第2期 97-102页

作者：周汀陈旭昀章倩苓闵昊 ASIC & system State Key Laboratory China department of Electronics Engineering Fudan University Shanghai 200433

A new algorithm of vector quantization (VQ) suitable for VLSI implementation is proposed. In this algorithm, a large number of codewords will be rejected before computing its MAE while the image quality is maintained. A criterion of distortion measure, the presorted codebook, a nearest neighbors search algorithm and a dichotomy search method adopted in the proposed algorithm have resulted in a considerable reduction in the complexity of VLSI implementation.

关键词： image coding vector quantization VLSI.

Inducible RNA targeting and N^(6)-methyladenosine editing by a split-Cas13 architecture

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Journal of Molecular Cell Biology 2024年第1期16卷 66-69页

作者： Yang Li Qiang Sun Zhi Yang Gang Yuan International Institutes of Medicine the Fourth Affiliated Hospital of Zhejiang University School of MedicineYiwu 322000China department of Thoracic Surgery and Institute of Thoracic Oncology West China HospitalSichuan UniversityChengdu 610041China Future Health Laboratory Innovation Center of Yangtze River DeltaZhejiang UniversityJiaxing 314100China

Dear editor,Cas13,a class Ⅱ type Ⅵ CRISPR‒Cas endonuclease with two higher eukaryotes and prokaryotes nucleotide-binding(HEPN)domains,exclusively binds to and cleaves single-stranded RNA by a complementary guide RNA(gRNA)(Makarova et al.,2020).RfxCas13d(also known as CasRx)is an ortholog of CRISPR‒Cas13 with a relatively small size and robust RNA knockdown capability in mammalian cells(Konermann et al.,2018).Owing to its simplicity and high efficiency,CasRx has been applied for RNA targeting in various types of cells and ***,most of these studies failed to control the nuclease activity of CasRx *** re-engineered split-Cas9 system enables inducible genome editing and epigenetic modulation through chemical-induced reassembly of the Cas9 protein(Zetsche et al.,2015).However,tools that allow for efficient and controllable RNA knockdown by a split-Cas13 system remain to be established.

关键词： split system simplicity

Carbon nanotubes for electronics manufacturing and packaging:from growth to integration

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Advances in Manufacturing 2013年第1期1卷 13-27页

作者： Johan Liu Di Jiang Yifeng Fu Teng Wang department of Microtechnology and Nanoscience Chalmers University of Technology Key Laboratory of Advanced Display and system Applications and SMIT Center School of Automation and Mechanical Engineering Shanghai University SHT Smart High Tech AB Fysikgrnd 3412 96 GothenburgSweden

Carbon nanotubes （CNTs） possess excellent electrical, thermal and mechanical properties. They are light in weight yet stronger than most of the other materials. They can be made both highly conductive and semi-conductive. They can be made from nano-sized small catalyst particles and extend to tens of millimeters long. Since CNTs emerged as a hot topic in the early 1990s, numerous research efforts have been spent on the study of the various properties of this new material. CNTs have been proposed as alternative materials of potential excellence in a lot of applications such as electronics, chemical sensors, mechanical sensors/actuators and composite materials, etc. This paper reviews the use of CNTs particularly in electronics manufacturing and packaging field. The progresses of three most important applications, including CNT-based thermal interface materials, CNT-based interconnections and CNT-based cooling devices are reviewed. The growth and post-growth processing of CNTs for specific applications are introduced and the tai- loring of CNTs properties, i.e., electrical resistivity, thermal conductivity and strength, etc., is discussed with regard to specific application requirement. As the semiconductor industry is still driven by the need of getting smaller and faster, CNTs and the related composite systems as emerging new materials are likely to provide the solution to the future challenges as we make more and more complex electronics devices and systems.

关键词： Carbon nanotubes Electronicsmanufacturing Electronics packaging - Growth Integration

揭示银关联缺陷的双重作用:环保型AgIn0.5Ga0.5S2中发光和载流子动力学的操纵者

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Science China Materials 2024年第1期67卷 214-222页

作者：刘高豫徐丽丽胡扬李晓明 Seokwoo Jeon 张胜利曾海波 MIIT Key Laboratory of Advanced Display Materials and Devices School of Materials Science and EngineeringNanjing University of Science and TechnologyNanjing 210094China department of Materials Science and Engineering Korea UniversitySeoul02841Republic of Korea

AgIn_(0.5)Ga_(0.5)S_(2)由于环境友好、合成成本低、成分灵活可调等优点在许多领域受到广泛关注.适当的直接带隙、无禁戒跃迁和高激子结合能使其成为一种有前途的发光材料.多组分体系的演化丰富了光电特性,并使其本征缺陷更加复杂.反过... 详细信息

AgIn_(0.5)Ga_(0.5)S_(2)由于环境友好、合成成本低、成分灵活可调等优点在许多领域受到广泛关注.适当的直接带隙、无禁戒跃迁和高激子结合能使其成为一种有前途的发光材料.多组分体系的演化丰富了光电特性,并使其本征缺陷更加复杂.反过来,这些缺陷对光电性能有重要影响,从而影响其发光性能.然而,对于这类半导体,在实验中观察到的与发光相对应的点缺陷的微观机制大多是未知的或间接推断的.本工作系统地揭示了AgIn_(0.5)Ga_(0.5)S_(2)的微观缺陷与发光之间的机制.热力学稳定性表明AgIn_(0.5)Ga_(0.5)S_(2)是亚稳态的并且与次生相之间存在显著的竞争.此外,计算的缺陷结果表明,与银关联的缺陷是幕后操纵者.两个浅能级缺陷(VAg和Agi)充当载流子提供者,而四个深能级反位缺陷(AgIn,AgGa,InAg和GaAg)充当载流子湮灭者.最后,载流子动力学的研究揭示了四种深能级反位缺陷对载流子辐射过程的不利影响.这些旨在为AgIn_(0.5)Ga_(0.5)S_(2)在发光领域的功能应用提供重要指导.

关键词：深能级反位缺陷发光材料本征缺陷浅能级热力学稳定性禁戒跃迁多组分体系

Comparison of variability and change rate in tropospheric NO_(2) column obtained from satellite products across China during 1997–2015

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International Journal of Digital Earth 2017年第8期10卷 814-828页

作者： Dongmei Chen Yao Feng Xiuying Zhang department of Geography and Planning Queen’s UniversityKingstonOntarioCanada School of Geography and Remote Sensing Nanjing University of Information Science&TechnologyNanjingPeople’s Republic of China International Institute of Earth system Science Nanjing UniversityNanjingJiangsuPeople’s Republic of China

Tropospheric NO_(2) column(TNC)products retrieved from five satellites including GOME/ERS-2(H,1997–2002),SCIAMACHY(S,2003–2011),OMI(O,2005–2015),GOME-2/METOP_A(A,2007–2013)and GOME-2/METOP_B(B,2013–2015)were compared in terms of their spatiotemporal variability and changes over *** temporal series of H suggested an increasing trend of TNC from 1997 to 2002,those of S,O and A revealed further increasing trends until the highest level of TNC was reached in 2011,but decreasing trends were detected by those of O and B from 2011 to ***,TNC was the highest in winter and the lowest in *** and changes from satellite TNC products are also analyzed in different regions of ***,it was the highest in North China and the lowest in Tibetan Plateau based on five ***,TNCs from A,B and S were higher than that from O;and TNC from S was larger than that from A at the country *** higher TNC the region has,the larger difference satellite products would ***,different datasets reached a good agreement in the spatial pattern of trends in TNC with highly significant increasing trends detected in North China.

关键词： Tropospheric NO_(2)column satellite products spatialtemporal change China

Lidar-Visual-Inertial Odometry with Online Extrinsic Calibration

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Journal of Shanghai Jiaotong university(Science) 2023年第1期28卷 70-76页

作者：茅天阳赵文韬王景川陈卫东 department of Automation Institute of Medical RoboticsShanghai Jiao Tong UniversityShanghai 200240China Key Laboratory of system Control and Information Processing of Ministry of Education Shanghai 200240China Shanghai Engineering Research Center of Intelligent Control and Management Shanghai 200240China

To achieve precise localization,autonomous vehicles usually rely on a multi-sensor perception system surrounding the mobile *** is a time-consuming process,and mechanical distortion will cause extrinsic calibration ***,we propose a lidar-visual-inertial odometry,which is combined with an adapted sliding window mechanism and allows for online nonlinear optimization and extrinsic *** the adapted sliding window mechanism,spatial-temporal alignment is performed to manage measurements arriving at different *** nonlinear optimization with online calibration,visual features,cloud features,and inertial measurement unit(IMU)measurements are used to estimate the ego-motion and perform extrinsic *** experiments were carried out on both public datasets and real-world *** indicate that the proposed system outperforms state-of-the-art open-source methods when facing challenging sensor-degenerating conditions.

关键词： autonomous vehicles multi-sensor fusion online calibration