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An improved adaptive differential evolution algorithm for single unmanned aerial vehicle multitasking

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Defence Technology（防务技术） 2021年第6期17卷 1967-1975页

作者： Jian-li su Hua Wang School of Astronautics Beihang UniversityBeijing100191China

Single unmanned aerial vehicle(UAV)multitasking plays an important role in multiple UAVs cooperative control,which is as well as the most complicated and hardest *** paper establishes a threedimensional topographical map,and an improved adaptive differential evolution(IADE)algorithm is proposed for single UAV *** an optimized problem,the efficiency of using standard differential evolution to obtain the global optimal solution is very low to avoid this ***,the algorithm adopts the mutation factor and crossover factor into dynamic adaptive functions,which makes the crossover factor and variation factor can be adjusted with the number of population iteration and individual fitness value,letting the algorithm exploration and development more *** experimental results implicate that the IADE algorithm has better performance,higher convergence and efficiency to solve the multitasking problem compared with other algorithms.

关键词： Unmanned aerial vehicle Multitasking Adaptive differential evolution Mutation factor Crossover factor

Packet track and traceback mechanism against denial of service attacks

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The Journal of China Universities of Posts and Telecommunications 2008年第3期15卷 51-58页

作者： li li SHEN su-bin Institute of Information Network Technology Nanjing University of Posts and Telecommunications Nanjing 210003 China

The denial of service attack is a main type of threat on the Internet today. On the basis of path identification （Pi） and Internet control message protocol （ICMP） traceback （iTrace） methods, a packet track and traceback mechanism is proposed, which features rapid response and high accuracy. In this scheme, routers apply packet marking scheme and send traceback messages, which enables the victim to design the path tree in peace time. During attack times the victim can trace attackers back within the path tree and perform rapid packet filtering using the marking in each packet. Traceback messages overcome Pi＇s limitation, wherein too much path information is lost in path identifiers; whereas path identifiers can be used to expedite the design of the path-tree, which reduces the high overhead in iTrace. Therefore, our scheme not only synthesizes the advantages but also compromises the disadvantages of the above two methods. Simulation results with NS-2 show the validity of our scheme.

关键词： denial of service (DoS) attack traceback packet marking Pi

基于固定化金属亲和整体柱的痕量微囊藻毒素富集分析

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分析测试学报 2025年第1期44卷 155-162,171页

作者：陈小燕杨玲苏立燊吴晓苹福州大学化学学院食品安全与生物分析教育部重点实验室福建福州350116 泉州市晋江环境监测站福建泉州362200 福建省妇幼保健院福建福州350001

基于固定化金属亲和色谱(IMAC)识别原理,采用后修饰法在热引发自由基聚合反应得到的有机基质整体柱上直接固定Cu^(2+),设计并合成表征了poly(VIM-co-DVB)-Cu^(2+)亲和毛细管整体柱,用于微囊藻毒素(MCs)的富集研究。详细优化了亲和整体... 详细信息

基于固定化金属亲和色谱(IMAC)识别原理,采用后修饰法在热引发自由基聚合反应得到的有机基质整体柱上直接固定Cu^(2+),设计并合成表征了poly(VIM-co-DVB)-Cu^(2+)亲和毛细管整体柱,用于微囊藻毒素(MCs)的富集研究。详细优化了亲和整体柱的萃取条件,在最优条件下,将poly(VIM-co-DVB)-Cu^(2+)整体柱用于毛细管微萃取(CME),并与高效液相色谱-质谱(HPLC-MS)检测技术联用,建立了环境水样品中3种MCs的高效富集分析方法。方法检出限为0.89~1.23 ng/L,加标回收率为80.0%~105%,相对标准偏差(RSD)不大于6.8%。该方法灵敏度高、准确性好,可为污染水体中微囊藻毒素的监测分析提供有效手段。

关键词：微囊藻毒素固定化金属亲和整体柱毛细管微萃取高效液相色谱-质谱

Peptidomimetics and metalloprotease inhibitors as anticancer drugs

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Science China Chemistry 2009年第5期52卷 535-548页

作者： su li XU WenFang School of Pharmaceutical Sciences Shandong UniversityJinan 250012China

Peptidomimetics with three types, as the structural or functional mimetics of natural active peptides, can preserve the bioactivity and improve the bioavailability and the specificity towards the targets of the lead peptides. Peptidomimetics of high bioactivity can be designed through various ways including conformation restriction, modification and non-peptide design. Recently the concentration on the de-velopment of cancer chemotherapeutic drugs was transferred from cytotoxic drugs to target-based drugs, and many proteases and peptidases that play key roles in the process of tumor genesis and development was discovered, which means that peptidomimetics as potential cancer chemotherapeu-tic drugs should be paid close attention to. Our laboratory has focused on the development of small-molecule peptidomimetic inhibitors of APN, MMPs and HDACs as target-based anticancer agents. These three zinc-dependent metalloproteinases play very important roles in the process of tumor genesis, invasion, metastasis, angiogenesis and matrix degradation, so small-molecule peptidomimetic inhibitors based on them would be quite potential in the development of chemotherapeutic drugs with high selectivity.

关键词： peptidomimetics drug design metalloproteinase inhibitors anticancer agents

Reliability analysis of urban gas transmission and distribution system based on FMEA and correlation operator

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Frontiers in Energy 2014年第4期8卷 443-448页

作者： su li Weiguo ZHOU School of Mechanical Engineering Tongji University Shanghai 200092 China

In order to improve the safety management of urban gas transmission and distribution system, failure mode and effects analysis （FMEA） was used to construct the reliability analysis system of the pipeline network. To solve the problem of subjectivity and uncertainty of the multi-expert decision making, the correlation operator was introduced into the calculation of the risk priority number （RPN）. Using FMEA along with weight analysis and expert investigation approach, the FMEA evaluation table was given, including five failure modes, risk priority numbers, failure causes and effects, as well as corrective actions. The results show that correlation operator can directly process the linguistic terms and quantify the priority of the risks.

关键词： gas transmission and distribution system risk evaluation reliability analysis failure mode and effects analysis (FMEA) correlation operator

Metallogenic Correlations for the Fe-Nb-REE Mineralization in the West Mine of the Bayan Obo Deposit, Inner Mongolia, China

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Acta Geologica Sinica(English Edition) 2018年第2期92卷 614-626页

作者： su li PENG suping China State Key Laboratory of Coal Resources and Safe Mining China University of Mining and Technology College of Mining and Coal Engineering Inner Mongolia University of Science and Technology

The West Mine of the Bayan Obo deposit, located in the northern-central part of Inner Mongolia, China, is enriched in Nb, rare earth elements and iron （Nb-REE-Fe） mineral resources. This paper presents a combined method to explore metallogenic correlation of the Nb-REE-Fe mineralization at the Bayan Obo West Mine. The method integrates factor analysis and Back Propagation （BP） neural network technology into processing and modeling of geological data. In this study, the Nb and REE contents of samples were transformed into discrete values to analyze the correlations among the metallogenic elements. The results show weak mineralization correlations between Nb and REEs. Nb and U are closely related in the geochemical patterns, while Fe is closely related to both Th and Mn. LREEs are an important factor for the mineralization of the Bayan Obo deposit, while Fe and Nb can be considered as the results of passive mineralization. On the basis of a metallogenic correlation analysis, the factors affecting the Fe-REE-Nb mineralization were extracted, and the Nb mineralization model was established by the BP neural network. Based on the BP neural network data computing, the variability of the Nb concentration displays a coupled multi-factor nonlinear relationship, which can be used to reveal the inherent metallogenic elemental regularities and predict the degree of element mineralization enrichment in the mining area.

关键词： Factor analysis BP neural network metallogenic correlation mineralization prediction modeling Bayan Obo deposit

PQBP1:A New Player in Metabotropic Glutamate Receptor Signaling and Synaptic Plasticity

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Neuroscience Bulletin 2021年第11期37卷 1637-1638页

作者： li-Da su Ying Shen Neuroscience Care Unit Second Affiliated Hospital of Zhejiang University School of MedicineHangzhou310009China Department of Physiology Zhejiang University School of MedicineHangzhou310058China

Group 1 metabotropic glutamate receptors(Gp1 mGluRs),comprising mGluR1 and mGluR5,are predominantly located at postsynaptic ***1 mGluRs induce the activation of phospholipase C-γ.

关键词： mGluR5 Metab Receptor

Rheological Properties of Mantle Peridotites at Yushigou in the North Qilian Mountains and Their Implicationsfor Plate Dynamics

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Acta Geologica Sinica(English Edition) 1998年第2期72卷 131-141,242页

作者： SONG Shuguang su li Xi'an Institute of Geology and Mineral Resources CAGS166 East Youyi Rd.Xi'anShaanxi 710054

Abstract: This paper discusses in detail the deformation textures, glide system, petrofabrics and olivine dislocation microstructures of mantle peridotites at Yushigou in the North Qilian Mountains, northwestern China. The peridotites have undergone high-pressure, high-temperature and low-strain rate plastic flow deformation. According to the dynamic recrystallized-grain size of olivine and the average spacing between the dislocation walls as well as the chemical composition of enstatite, the authors calculated the rheological parameters of the ancient upper mantle in the study area as follows: temperatures 1025–1093°C; pressures 3043–4278 MPa; depths 95–132 km; deviatoric stress 28–32 MPa; strain rates 0.2×10?14-2.13×10?14s?1 and equivalent viscosities 0.45×1020-4.65×1020 Pa ? s. These parameters suggest that the position where plastic flow took place was correspondent to the lowvelocity zone beneath the oceanic lithosphere and that oceanization characterized by middle-velocity (1–3 cm/a) sea-floor spreading took place in the North Qilian Mountains during the Early Palaeozoic.

关键词： oceanic mantle rocks rheology sea-floor spreading North Qilian Mountains

Opportunistic spectrum sharing in software defined wireless network

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Journal of Systems Engineering and Electronics 2014年第6期25卷 934-941页

作者： Mao Yang Yong li Depeng Jin li su lieguang Zeng Department of Electronic Engineering Tsinghua University

Over the past few decades, the world has witnessed a rapid growth in mobile and wireless networks（MWNs） which significantly change human life. However, proliferating mobile demands lead to several intractable challenges that MWN has to face. Software-defined network is expected as a promising way for future network and has captured growing attention. Network virtualization is an essential feature in software-defined wireless network（SDWN）, and it brings two new entities, physical networks and virtual networks. Accordingly, efficiently assigning spectrum resource to virtual networks is one of the fundamental problems in SDWN. Directly orienting towards the spectrum resource allocation problem, firstly, the fluctuation features of virtual network requirements in SDWN are researched, and the opportunistic spectrum sharing method is introduced to SDWN. Then, the problem is proved as NP-hardness. After that, a dynamic programming and graph theory based spectrum sharing algorithm is *** demonstrate that the opportunistic spectrum sharing method conspicuously improves the system performance up to around 20%–30% in SDWN, and the proposed algorithm achieves more efficient performance.

关键词： software-defined network(SDN) wireless virtualiza-tion opportunistic spectrum sharing dynamic programming graph theory