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山东科学 2009年第5期22卷 84-88页

作者：田敏山东省计算中心山东济南250014

单标量乘和多点标量乘是椭圆曲线密码体制中最主要的运算，在各种密码协议中起到核心作用。提出一种基于Shamir方法优化预计算的多标量乘算法，算法对标量从左到右进行编码，并将编码阶段与多标量乘的主计算阶段合并进行，节省了存储标... 详细信息

单标量乘和多点标量乘是椭圆曲线密码体制中最主要的运算，在各种密码协议中起到核心作用。提出一种基于Shamir方法优化预计算的多标量乘算法，算法对标量从左到右进行编码，并将编码阶段与多标量乘的主计算阶段合并进行，节省了存储标量新编码的内存空间，更适合于内存受限的无线环境中应用。分析表明新算法在一般情况下效率可提高6％～50％。

关键词：无线网络椭圆曲线密码多标量乘 Shamir方法

Delivery Efficiency and Supplier Performance Evaluation in china's E-retailing Industry

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Journal of Systems science & Complexity 2017年第2期30卷 392-410页

作者： SHI Yong YANG Zhuofan YAN Hong tian Xin Research center on Fictitious Economy&Data science Chinese Academy of SciencesBeijing 100190China School of Economics and Management University of Chinese Academy of SciencesBeijing 100190China Key Research Laboratory of Big Data Mining and Knowledge Management Chinese Academy of SciencesBeijing 100190China Department of Logistics and Maritime Studies Faculty of Business The Hong Kong Polytechnic UniversityHong KongChina

This paper focuses on overall and sub-process supply chain efficiency evaluation using a network slacks-based measure model and an undesirable directional distance model. Based on a case analysis of a leading Chinese B2 C firm W, a two-stage supply chain structure covering procurementstock and inventory-sale management is constructed. The research shows overall supply chain inefficiency is attributable to procurement-stock conversion inefficiency. From a view of operations model,the third-party platform model is more efficient than a "shop in shop" self-operated model. However,the self-operated mode performs better in product categories such as computer & Office & digital, food& drink and healthy products due to these products' delivery characteristics and consumers' shopping habits. In the logistics selection, most e-retail players are inclined to choose the hybrid model of 3 PL and self-operated logistics with the product category extension from vertical model to all-category model. These findings may help managers improve supplier-buyer relationship and strengthen supply chain management. This research offers a new explanation regarding the failure of e-retail supply chain.

关键词： Efficiency e-retail performance evaluation supply chain virtual business

Reconstruction of plasmoid and traveling compression region in the near-Earth magnetotail

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science china(Technological sciences) 2015年第2期58卷 330-337页

作者： LU Shang Wen ZONG Qiu Gang VOGIATZIS Ioannis WANG Yong Fu tian An Min Institute of Space Physics and Applied Technology Peking University Department of Electrical and computer Engineering Democritus University of Thrace shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment School of Space Science and PhysicsShandong University at Weihai

Cluster spacecraft observed an earthward flowing plasmoid along with a travelling compression region （TCR） structure in southern plasma sheet boundary layer （PSBL） at 21：09 UT of September 19, 2001. We have reconstructed the two-dimensional topology of the magnetic field structure observed by C1 using Grad-Shafranov reconstruction method. Results show that CI passed through part of a plasmoid, which compressed the lobe magnetic field and formed a TCR. The size of the whole plas- moid structure in X direction is estimated to be about 3 Re. Furthermore, using multi-spacecraft observations, we have found some detailed information about this structure. First, C1 observed bi-streaming electron components, which supports our sug- gestion that the spacecraft passed through closed field lines. Second, a small magnetic field perturbation within this plasmoid accompanied by slight decrease in electron flux suggests that a flux rope core might exist at the center of the plasmoid.

关键词： plasma sheet boundary layer plasmoid traveling compression region Grad-Shafranov method

Difficulty-aware prior-guided hierarchical network for adaptive segmentation of breast tumors

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science china(Information sciences) 2023年第2期66卷 127-141页

作者： Sumaira HUSSAIN Xiaoming XI Inam ULLAH Syeda Wajiha NAIM Kashif SHAHEED Cuihuan tian Yilong YIN School of Software Engineering Shandong University Department of computer science Sindh Madressatul Islam University School of computer science and Technology Shandong Jianzhu University School of computer science and Engineering South China University of Technology School of Medicine Shandong University Health Management center Qilu Hospital of Shandong University

Breast tumor segmentation is vital to tumor detection at the early stages. Deep learning methods are typically used in automatic tumor segmentation tasks. However, in existing methods, the difference between pixels is disregarded, and the union network architecture is used to segment all pixels; these methods involve a tradeoff between accuracy and efficiency. A novel, difficulty-aware, prior-guided hierarchical network for the adaptive segmentation of breast tumors is presented herein. A difficulty prior learning module is proposed to learn the pixel’s difficulty prior to guild adaptive segmentation in the proposed network. To achieve a more accurate segmentation of hard pixels, a hard pixel processing unit is presented to learn more discriminative features for hard pixels. Experiments are conducted based on three datasets. The experimental results show that the proposed methods outperform traditional deep learning methods and achieve a balance between accuracy and efficiency.

关键词： breast tumor ultrasound image segmentation deep neural network difficulty-awareness

Polymerization-Amplified Photoacoustic Signal by Enhancing Near-Infrared Light-Harvesting Capacity and Thermal-to-Acoustic Conversion

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Chinese Journal of Polymer science 2022年第9期40卷 1090-1100页

作者： He-Qi Gao Jing-tian Zhang Xin-Wen Qi Di Jiao Yu-Ning Hong Ke Shan Xiang-Long Kong Dan Ding Key Laboratory of Bioactive Materials Ministry of Educationand College of Life SciencesNankai UniversityTianjin 300071China center for AIE Research Shenzhen Key Laboratory of Polymer Science and TechnologyGuangdong Research Center for Interfacial Engineering of Functional MaterialsCollege of Materials Science and EngineeringCollege of Physics and Optoelectronic EngineeringShenzhen UniversityShenzhen 518060China Department of Chemistry and Physics La Trobe Institute for Molecular ScienceLa Trobe UniversityMelbourneVictoria3086Australia shandong Artificial intelligence Institute and shandong computer science center Qilu University of TechnologyJinan 250353China

As a frontier imaging technique for biomedical applications,photoacoustic(PA)imaging has been developed *** development of new design strategies and excellent PA imaging reagents to boost PA conversion is eagerly desirable for high quality PA imaging but complicated to ***,we develop a new strategy in which PA imaging reagents with better properties can be easily optimized by polymerization.A series of new PA imaging reagents were designed and *** polymerization strategy can effectively promote the PA signal by specifically increasing the thermal-to-acoustic conversion *** these materials shared the same building units,the optimized effectiveness of polymerization strategy in terms of near-infrared light-harvesting capacity and thermal-to-acoustic conversion efficiency are discussed,*** polymers with intense intramolecular motion exhibit an amplified PA signal by elevating thermal-to-acoustic conversion and its higher light-harvesting capability at redshifted *** simultaneously strong PA signal and photothermal conversion efficiency of p-TTmB NPs enable precise PA imaging and effective photothermal *** work highlights a simple and available design guideline of polymerization for amplifying the PA effect and optimizing existing materials.

关键词： Intramolecular motion Thermal-to-acoustic conversion Photoacoustic imaging Photothermal conversion efficiency Polymerization

Impact of intensity variability of the Asian summer monsoon anticyclone on the chemical distribution in the upper troposphere and lower stratosphere

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Atmospheric and Oceanic science Letters 2022年第3期15卷 25-30页

作者： Kecheng Peng Jiali Luo Jiayi Mu Xiaoqun Cao Hongying tian Lin Shang Yanan Guo College of Meteorology and Oceanography National University of Defense TechnologyChangshaChina Key Laboratory of Semi-Arid Climate Change and College of Atmospheric sciences Lanzhou UniversityLanzhouChina College of computer National University of Defense TechnologyChangshaChina shandong Provincial Climate center JinanChina Trainer Simulation Training center of Naval Aeronautical University HuludaoChina

During the Asian summer monsoon(ASM)season,the process of stratosphere-troposphere exchange significantly affects the concentration and spatial distribution of chemical constituents in the upper troposphere and lower stratosphere(UTLS).However,the effect of the intensity of the Asian summer monsoon anticyclone(ASMA)on the horizontal distribution of chemical species within and around the ASMA,especially on the daily time scale,remains ***,the authors use the MERRA-2 reanalysis dataset and Aura Microwave Limb Sounder observations to study the impact of ASMA intensity on chemical distributions at 100 hPa during the ASM *** intraseasonal variation of ASMA is classified into a strong period(SP)and weak period(WP),which refer to the periods when the intensity of ASMA remains strong and weak,*** relatively low ozone(O_(3))region is found to be larger at 100 hPa during SPs,while its mixing ratio is lower than during WPs in *** June,analysis shows that the O_(3) horizontal distribution is mainly related to the intensity of AMSA,especially during SPs in June,while deep convections also impact the O_(3) horizontal distribution in July and *** results indicate that the intraseasonal variation of the ASMA intensity coupled to deep convection can significantly affect the chemical distribution in the UTLS region during the ASM season.

关键词： Asian summer monsoon anticyclone Intensity index Chemical distribution Deep convection

Identification of Cognitive Dysfunction in Patients with T2DM Using Whole Brain Functional Connectivity

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Genomics, Proteomics & Bioinformatics 2019年第4期17卷 441-452页

作者： Zhenyu Liu Jiangang Liu Huijuan Yuan Taiyuan Liu Xingwei Cui Zhenchao Tang Yang Du Meiyun Wang Yusong Lin Jie tian CAS Key Laboratory of Molecular Imaging Institute of AutomationChinese Academy of SciencesBeijing 100190China School of computer and Information Technology Beijing Jiaotong UniversityBeijing 100044China Department of Endocrinology and Metabolism Henan Provincial People’s Hospital&the People’s Hospital of Zhengzhou UniversityZhengzhou 450003China Department of Radiology Henan Provincial People’s Hospital&the People’s Hospital of Zhengzhou UniversityZhengzhou 450003China Cooperative Innovation center for Internet Healthcare&School of Software Zhengzhou UniversityZhengzhou 450003China School of Mechanical Electrical&Information EngineeringShandong University(Weihai)Weihai 264209China University of Chinese Academy of sciences Beijing 100080China Beijing Advanced Innovation center for Big Data-Based Precision Medicine School of MedicineBeihang UniversityBeijing 100191China Engineering Research center of Molecular and Neuro Imaging of Ministry of Education School of Life Science and TechnologyXidian UniversityXi’an 710126China

Majority of type 2 diabetes mellitus(T2DM)patients are highly susceptible to several forms of cognitive impairments,particularly ***,the underlying neural mechanism of these cognitive impairments remains *** aimed to investigate the correlation between whole brain resting state functional connections(RSFCs)and the cognitive status in 95 patients with *** constructed an elastic net model to estimate the Montreal Cognitive Assessment(MoCA)scores,which served as an index of the cognitive status of the patients,and to select the RSFCs for further ***,we utilized a machine learning technique to evaluate the discriminative ability of the connectivity pattern associated with the selected *** estimated and chronological MoCA scores were significantly correlated with R=0.81 and the mean absolute error(MAE)=***,cognitive impairments of patients with T2DM can be identified using the RSFC pattern with classification accuracy of 90.54%and the area under the receiver operating characteristic(ROC)curve(AUC)of *** connectivity pattern not only included the connections between regions within the default mode network(DMN),but also the functional connectivity between the task-positive networks and the DMN,as well as those within the task-positive *** results suggest that an RSFC pattern could be regarded as a potential biomarker to identify the cognitive status of patients with T2DM.

关键词： Type 2 diabetes mellitus Resting state functional connectivity Elastic net Support vector machines MoCA

A Novel Early Warning Model for Hand, Foot and Mouth Disease Prediction Based on a Graph Convolutional Network

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Biomedical and Environmental sciences 2022年第6期35卷 494-503页

作者： JI tian Jiao CHENG Qiang ZHANG Yong ZENG Han Ri WANG Jian Xing YANG Guan Yu XU Wen Bo LIU Hong Tu NHC Key Laboratory of Medical Virology and Viral Diseases National Institute for Viral Disease Control and PreventionChinese Center for Disease Control and PreventionBeijing 100026China Academy of Cyber science and Engineering Southeast UniversityNanjing 211189JiangsuChina center for Biosafety Mega science Chinese Academy of SciencesWuhan 430071HubeiChina Guangdong center for Disease Control and Prevention Guangzhou 511430GuangdongChina shandong center for Disease Control and Prevention Jinan 250014ShandongChina LIST Key Laboratory of Computer Network and Information Integration(Southeast University)Ministry of EducationSoutheast UniversityNanjing 211189JiangsuChina

Objectives Hand,foot and mouth disease(HFMD)is a widespread infectious disease that causes a significant disease burden on *** achieve early intervention and to prevent outbreaks of disease,we propose a novel warning model that can accurately predict the incidence of *** We propose a spatial-temporal graph convolutional network(STGCN)that combines spatial factors for surrounding cities with historical incidence over a certain time period to predict the future occurrence of HFMD in Guangdong and shandong between 2011 and *** 2011-2018 data served as the training and verification set,while data from 2019 served as the prediction *** important parameters were selected and verified in this model and the deviation was displayed by the root mean square error and the mean absolute *** As the first application using a STGCN for disease forecasting,we succeeded in accurately predicting the incidence of HFMD over a 12-week period at the prefecture level,especially for cities of significant *** This model provides a novel approach for infectious disease prediction and may help health administrative departments implement effective control measures up to 3 months in advance,which may significantly reduce the morbidity associated with HFMD in the future.

关键词： HFMD Early warning model STGCN Disease prediction

Dynamically taming focal fields of femtosecond lasers for fabricating microstructures

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Chinese Optics Letters 2022年第1期20卷 6-11页

作者： Meng-Qiang Cai Qiang Wang Cheng-Hou Tu Yong-Nan Li Hui-tian Wang School of Physics and Key Laboratory of Weak Light Nonlinear Photonics Nankai UniversityTianjin 300071China Institute of Space science and Technology Nanchang UniversityNanchang 330031China National Laboratory of Solid State Microstructures Nanjing UniversityNanjing 210093China Collaborative Innovation center of Advanced Microstructures Nanjing UniversityNanjing 210093China Collaborative Innovation center of Light Manipulations and Applications Shandong Normal UniversityJinan 250358China

Micromachining based on femtosecond lasers usually requires accurate control of the sample movement,which may be very complex and ***,the exploration of micromachining without sample movement is ***,we have illustrated the manipulation of optical fields by controlling the polarization or phase to vary periodically and then realized certain focal traces by real-time loading of the computer-generated holograms(CGHs) on the spatial light *** focal trace is composed of many discrete focal spots,which are generated experimentally by using the real-time dynamically controlled *** the designed focal traces,various microstructures such as an ellipse,a Chinese character "Nan",and an irregular quadrilateral grid structure are fabricated in the z-cut LiNbO_(3) wafers,showing good qualities in terms of continuity and *** method proposes a movement free solution for micromachining samples and completely abandons the high precision stage and complex movement control,making microstructure fabrication more flexible,stable,and cheaper.

关键词： manipulation of optical fields computer-generated holograms focal trace microstructures