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Receiver Detection Employing Semaphore in Cognitive Radio

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China Communications 2010年第1期7卷 41-49页

作者： wang Weidong Li Fan Zhang Yinghai wang shoufeng wang Yongtao Beijing Jiaotong Univ Natl Engn Lab Next Generat Internet Interconnect Beijing 100044 Peoples R China

Interference from secondary users to primary users should be avoided in cognitive radio. However, it is difficult to solve the interference problem if the secondary users cannot get the information of the primary receivers. Insufficient information of primary users would result in inaccurate spectrum detecting result. To deliver the information of primary users, Receiver Detection Employing Semaphore (ReDES) is proposed in this paper. Primary receiver informs secondary users of its licensed receive frequency according to semaphore architecture directly in ReDES. The semaphore is used to determine the spectrum holes by secondary users. Frequency mapping method is come up with as a realization of ReDES. The procedure and the detailed techniques are illustrated to make ReDES scheme reasonable and feasible. Simulation results show that the proposed scheme can effectively detect the frequencies of primary receivers, and improve the accuracy of spectrum detection.

关键词： cognitive radio receiver detection hidden terminal problem.

Synthesis of high molecular weight polylactic acid from aqueous lactic acid co-catalyzed by tin(II)chloride dihydrate and succinic anhydride

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Chinese Science Bulletin 2005年第20期50卷 2390-2392页

作者： LEI Ziqiang BAI Yanbin wang shoufeng Key Laboratory of Polymer Materials of Gansu Province College of Chemistry and Chemical Engineering Northwest Normal University Lanzhou 730070 China

Polylactic acid was synthesized from commer- cial available cheap aqueous lactic acid (85%―90% w/w) using succinic anhydride and SnCl2·2H2O as catalyst in the absence of organic solvents. As a result, polylactic acid with a molecular weight of 60000 was prepared in 10 h. The new procedure is much simple, cheap and outstanding in that the start material is aqueous lactic acid; the catalytic system is environmentally benign.

关键词：聚合物催化剂有机溶剂分子结构乳酸

Magnetically Separable and Versatile Pd/Fe3O4 Catalyst for Efficient Suzuki Cross-Coupling Reaction and Selective Hydrogenation of Nitroarenes

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Chinese Journal of Chemistry 2011年第3期29卷 525-530页

作者： Zhang, Rongzhao Liu, Jianming Li, Fuwei wang, shoufeng Xia, Chungu Sun, Wei State Key Laboratory for Oxo Synthesis and Selective Oxidation Lanzhou Institute of Chemical Physics Chinese Academy of Sciences Lanzhou Gansu 730000 China Graduate School of the Chinese Academy of Sciences Beijing 100039 China

Magnetic nanoparticle-supported Pd/Fe3O4 was readily prepared and proved to be versatile catalyst for efficient Suzuki cross-coupling reaction, and the reduction of nitroarenes under mild conditions （balloon H2 pressure and room temperature）. The catalyst could be conveniently recovered and reused several times with sustained catalytic activity.

关键词： nanoparticles Fe3O4 supported catalyst Suzuki coupling reaction reduction

Future Point Estimation Method for Unpowered Gliding Targets

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Journal of Electronic Research and Application 2024年第6期8卷 162-169页

作者： shoufeng wang Jiangsu Automation Research Institute Lianyungang 222061Jiangsu ProvinceChina

In modern warfare,unpowered glide munitions,represented by JDAM,are widely *** predicting the future trajectory of such targets is crucial for intercepting *** paper proposes a future point prediction method for unpowered gliding targets based on attitude *** estimating the current state of the target,we derive the target’s attitude coordinate ***,the paper analyzes the forces acting on the target and updates the state transition matrix,ultimately calculating the future position of the *** results show that,compared to traditional methods,this approach improves the accuracy of future point predictions by 9%to 45%.

关键词： Guided bomb Extended Kalman filter Maneuver prediction Fire control calculation Attitude coordinate system Future point prediction

Expression of Drosophila melanogaster acetylcholinesterase(DmAChE) gene splice variants in Pichia pastoris and evaluation of its sensitivity to organophosphorus pesticides

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2021年第3期22卷 204-213页

作者： Liujia SHI Fangfang YANG Yanyan XU shoufeng wang Institute of Pharmaceutical Biotechnology School of MedicineZhejiang UniversityHangzhou 310058China Zhejiang Provincial Key Laboratory for Microbial Biochemistry and Metabolic Engineering Hangzhou 310058China

Acetylcholinesterase(AChE) is a key enzyme used to detect organophosphorus pesticide residues by the enzyme inhibition *** accidental discovery of a mutant strain with AChE activity was made in our laboratory during the process of AChE expression by Pichia *** pPIC9 K-Drosophila melanogaster acetylcholinesterase(DmAChE)-like expression vector was constructed by codon optimization of this mutant strain,which was transformed into *** GS115,and positive clones were selected on yeast peptone dextrose(YPD) plate with G418 at 4.0 mg/*** GS115-pPIC9 K-DmAChE-like strain was subjected to 0.5% methanol induction expression for 120 h,with a protein band at 4.3 kDa found by the tricine-sodium dodecyl sulfate-polyacrylamide gel electrophoresis(SDS-PAGE) pattern of the fermentation *** preliminary purification by ammonium sulfate precipitation,the enzyme activity was detected to be 76.9 U/(mL·min).In addition,the pesticide sensitivity test proved that DmAChE-like is selective and sensitive to organophosphorus pesticides.

关键词： Acetylcholinesterase(AChE) Pichia pastoris Enzyme activity determination Pesticide sensitivity

Intelligent Traffic Allocation Algorithm for Multiple Networks

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China Communications 2012年第12期9卷 127-136页

作者： Gao Peng Meng Dexiang wang shoufeng Zhang Dongchen Cheng Nan Research Division China Mobile Group Design Institute Co.Ltd.Beijing 100080P.R.China

In recent years, wireless communication systems have experienced tremendous growth in data traffic. Many capacity-enhancing techniques are applied to elevate the gap between the amount of traffic and network capacity, and more solutions are required to minimize the gap. Traffic allocation among multiple networks is regarded as one of the most effective methods to solve the problem. However, current studies are unable to derive the quantity of traffic that each network should carry. An intelligent traffic allocation algorithm for multiple networks is proposed to obtain the optimal traffic distribution. Multiple factors affecting traffic distribution are considered in the proposed algorithm, such as network coverage, network cost, user habit, service types, network capacity and terminals. Using evaluations, we proved that the proposed algorithm enables a lower network cost than load balancing schemes. A case study of strategy rmldng for a 2G system refarming is presented to further illustrate the applicability of the proposed algorithm. We demonstrated that the new algorithm could be applied in strategy rmldng for telecommunication operators.

关键词： traffic allocation strategy making network optimization

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一类lpp-半群的结构(英文)

数学进展 2008年第3期37卷 342-352页

作者：王守峰西南大学数学与统计学院

本文研究含左正则lpp-断面的lpp-半群的结构.特别地,给出了含右理想左正则lpp-断面的lpp-半群的一个结构.另外,还把这个结构用于一些特殊情况.

关键词： lpp-半群左正则lpp-断面强左正则lpp-断面右理想

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三氟甲基季碳中心的合成进展

有机化学 2020年第7期40卷 1901-1911页

作者：王守锋王文贵济南大学化学化工学院山东省氟化学化工材料重点实验室济南250022

三氟甲基是一个重要的含氟基团,常被应用于药物和农药领域.季碳中心是广泛存在于天然产物和合成药物中的结构.近年来,构建含有三氟甲基季碳中心的分子得到了快速发展.从直接三氟甲基化反应、新的合成砌块和新反应的探索几个方面,综述了... 详细信息

三氟甲基是一个重要的含氟基团,常被应用于药物和农药领域.季碳中心是广泛存在于天然产物和合成药物中的结构.近年来,构建含有三氟甲基季碳中心的分子得到了快速发展.从直接三氟甲基化反应、新的合成砌块和新反应的探索几个方面,综述了近十年来合成三氟甲基季碳中心的研究进展.

关键词：三氟甲基季碳中心合成进展

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水溶液中的Minisci反应研究进展

有机化学 2024年第7期44卷 2136-2146页

作者：王文贵王守锋济南大学化学化工学院、山东省氟化学化工材料重点实验室济南250022

Minisci反应是通过自由基中间体对缺电子含氮杂环化合物进行官能团化的方法.利用Minisci反应可以向未官能团化的缺电子含氮杂环上引入烷基、酰基、硅基、烷硫基、硼烷等,构建具有不同取代基的杂环化合物,是合成取代杂环的一个重要手段.... 详细信息

Minisci反应是通过自由基中间体对缺电子含氮杂环化合物进行官能团化的方法.利用Minisci反应可以向未官能团化的缺电子含氮杂环上引入烷基、酰基、硅基、烷硫基、硼烷等,构建具有不同取代基的杂环化合物,是合成取代杂环的一个重要手段.水作为一种绿色环保的溶剂,是进行有机反应的理想介质,在Minisci反应中得到了广泛应用.尽管从发现Minisci反应开始,水作为Minisci反应的介质就得到应用,但是水溶液中的Minisci反应仍然发展缓慢.从烷基化、芳基化和酰基化三个方面,根据不同的自由基前体,综述了水溶液中Minisci反应的进展.

关键词： Minisci反应自由基水溶液杂环化合物