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Robust multi-path routing for dynamic topology in wireless sensor networks

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The Journal of China Universities of Posts and Telecommunications 2007年第1期14卷 1-5页

作者： HUANG Ping tian hui ZHANG Ming ZHANG Ping Wireless Technology Innovation Institute Beijing University of Posts and Telecommunications Beijing 100876 China

Wirreless sensor networks are being widely researched and are expected to be used in several scenarios. On the leading edge of treads, on-demand, high-reliability, and low-latency routing protocol is desirable for indoor environment applications. This article proposes a routing scheme called robust multi-path routing that establishes and uses multiple node-disjoint routes. Providing multiple routes helps to reduce the route recovery process and control the message overhead. The performance comparison of this protocol with dynamic source routing （DSR） by OPNET simulations shows that this protocol is able to achieve a remarkable improvement in the packet delivery ratio and average end-to-end delay.

关键词： multiple node-disjoint routes finite-state Markov channel model high-reliability low-latency

ISSAMAC: a High Speed MAC Protocol for B3G Systems

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The Journal of China Universities of Posts and Telecommunications 2006年第1期13卷 53-59页

作者： GU Xue-lin tian hui YANG Ning ZHANG Ping ZHANG Ping College of Telecommunication Engineering Beijing University of Posts and Telecommunications Beijing 100876 P.R. China

Based on a discussion of the requirements for the multiple acess control protocol of beyond thlrd-generation mobile systems, we in this paper articulate the needs of the new multiple acess control protocol with support of high-speed transmission and guaranteed quality of service, for voice, video and audio. In light of these, we present the design of a new multiple acess control protocol, called intelligent slot-subcarriered assignment multiple acess control protocol, to support multiple service categories and to yield high spectral efficiency. Our simulation results verify that intelligent slot-subcarriered assignment multiple acess control protocol can not only provide low delays for the real-time traffic by using bandwidth reservation and effectual scheduling, but also make full use of the limited bandwidth by using a dynamic sub-carrier assignment algorithm.

关键词： B3G multiple acess control QoS OFDMA MIMO

Gas Generation from Coal and Coal-Measure Mudstone Source Rocks of the Xujiahe Formation in the Western Sichuan Depression,Sichuan Basin

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Journal of Earth Science 2023年第4期34卷 1012-1025页

作者： Zijin Wu Tengfei Li Sui Ji Qin Zhou hui tian State Key Laboratory of Organic Geochemistry Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China University of Chinese Academy of Sciences Beijing 100049China CAS Center for Excellence in Deep Earth Science Guangzhou 510640China

The Triassic and Jurassic tight sandstone gas in the western Sichuan depression,Sichuan Basin has attracted much attention in recent years,and the Upper Triassic coal-bearing Xujiahe Formation is believed to be the major source ***,there are relatively few studies on the carbon isotopic heterogeneity of methane generated from coal-measure source rocks and the origin of the natural gases in Xinchang Gas Field is still *** this study,one coal-measure mudstone sample and one coal sample of the Xujiahe Formation in western Sichuan Basin were selected for gold tube pyrolysis experiment to determine their gas generation *** extrapolation of gas generation and methane carbon isotope fractionation parameters reveals that the main gas generation stage of Xujiahe Formation ranges from Late Jurassic to Cretaceous in the Xinchang Gas *** natural gas in the 5th member of Xujiahe Formation in Xinchang Gas Field is mainly derived from the 5th member of Xujiahe Formation itself,i.e.,self-generation and self-reservoir,however,the gas in the Jurassic gas pools is mainly derived from the source rocks of the 3rd member of Xujiahe Formation rather than the 5th member of Xujiahe Formation.

关键词： western Sichuan Basin coal coal-measure mudstone Xujiahe Formation kinetics of methane carbon isotope fractionation.

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HPLC法测定麻杏止咳片中绿原酸的含量

湖北中医药大学学报 2024年第4期26卷 40-43页

作者：田辉付桃利黄胤湖北中医药大学附属武汉市中医医院湖北武汉430014

目的用高效液相色谱法测定麻杏止咳片中绿原酸的含量。方法采用XB-C_(18)(4.6 mm×250mm,5μm)色谱柱,流动相为乙腈-0.1%磷酸溶液,流速1.0 mL/min,柱温20℃,检测波长为326 nm,进样量为10μL。HPLC法测定麻杏止咳片中绿原酸的含量。结果... 详细信息

目的用高效液相色谱法测定麻杏止咳片中绿原酸的含量。方法采用XB-C_(18)(4.6 mm×250mm,5μm)色谱柱,流动相为乙腈-0.1%磷酸溶液,流速1.0 mL/min,柱温20℃,检测波长为326 nm,进样量为10μL。HPLC法测定麻杏止咳片中绿原酸的含量。结果绿原酸的进样量在0.625~15.000μg(R^(2)=0.9973)范围内与峰面积的线性关系良好。平均回收率为100.73%,RSD=1.05%。结论所建立的方法准确,重现性好,可用于麻杏止咳片中绿原酸含量的测定。

关键词：麻杏止咳片绿原酸高效液相色谱法含量测定

The trend of mechanizing road header for coal mine entry

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Journal of Coal Science & Engineering(China) 2010年第1期16卷 99-103页

作者： hui Xing-tian School of Architecture and Civil Engineering Xi＇an University of Science and Technology Xi＇an 710054 China

In discussing coal mine entry construction with rock bolt technology, examinedthe craft and machinery problems as well as the conditions in which to use each kind ofmachine and *** exposed the intrinsic flaws of the widely used road *** problemis that it was designed according to early timbering support state but is not suitable forrock bolt *** way to improve the function of existing road headers is notthrough parallel operations but using the SUDM (Shield Union Driving Machine), which isa new machine that improves *** article proposed a few solutions in designto solve this problem.

关键词： coalmine gateway mine entry construction road header mechanization suggestion

Thermal maturation as revealed by micro-Raman spectroscopy of mineral-organic aggregation (MOA) in marine shales with high and over maturities

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Science China Earth Sciences 2020年第10期63卷 1540-1552页

作者： Xianming XIAO Qin ZHOU Peng CHENG Jian SUN Dehan LIU hui tian School of Energy Resources China University of Geosciences(Beijing)Beijing 100083China State Key Laboratory of Organic Geochemistry Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China

Laser Raman spectroscopy of organic matter in coals and sedimentary rocks has been increasingly investigated to assess thermal *** organic matter such as vitrinite and solid bitumen,as well as isolated kerogen are definitely selected for this purpose,but there has been no systematic report on the Raman spectral parameters directly based on mineral-organic aggregations(MOA)in *** this paper,the Raman spectral characteristics and parameters of MOA in two sets of marine shale samples from southern China with either different TOC contents(TOC=0.10–4.59%)or different maturities(BRo=1.71–4.57%)were *** was found that the Raman technique is very sensitive to the organic matter in *** the TOC content of the shales reaches about 0.60%,perfect Raman spectra with D and G bands derived from organic matter in MOAwere obtained,and the Raman parameters of MOA are in good agreement with those of its associated solid bitumen,and can indicate the thermal maturity just like those of solid *** the Raman parameters of MOA is a potential alternative way to estimate maturity levels of high and over mature shales,especially those lower Paleozoic and Precambrian shales that lack macerals suitable for reflectance or Raman measurements.

关键词： Marine shale Mineral-organic aggregation(MOA) Solid bitumen Raman parameter Maturity

Duplicated transmission based-resource scheduling for uplink grant-free SCMA system

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The Journal of China Universities of Posts and Telecommunications 2020年第2期27卷 1-9页

作者： Xiao Jiali Nie Gaofeng Deng Gang tian hui Zhang Chong School of Information and Communication Engineering Beijing University of Posts and TelecommunicationsBeijing 100876China National Radio and Television Administration Academy of Broadcasting ScienceBeijing 100102China

Sparse code multiple access-based uplink grant-free transmission(SCMA-UGFT)has been proposed to realize ultra reliable and low latency communication(URLLC)in the fifth generation(5 G)*** the process of resource request and grant,users may collide in the same *** compensate the potential user performance decline,resource scheduling becomes a tough issue in the SCMA-UGFT *** article proposes a duplicated transmission-based resource scheduling(DTBRS)scheme for SCMA-UGFT system by considering the URLLC *** from the existing schemes,not only one shared basic transmission units(BTUs)are allocated to a user equipment(UE)in the proposed DTBRS scheme for initial transmission to realize the duplicated transmission and to guarantee the transmission ***,according to the proposed DTBRS scheme,one or two exclusive BTUs are assigned to a UE for retransmission to avoid the *** last,each packet is given a lifetime to limit the transmission latency to meet the URLLC latency *** simulation demonstrates that the DTBRS scheme can achieve a better performance than the existing state-of-the-art scheme in terms of the average packet drop rate.

关键词： grant-free SCMA resource scheduling URLLC

Optimal energy-efficient scheme for two-way relay channel using physical layer network coding

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The Journal of China Universities of Posts and Telecommunications 2011年第6期18卷 51-58页

作者： ZHOU Min CUI Qi-mei WANG hui TAO Xiao-feng tian hui MIKKO Valkama Key Laboratory of Universal Wireless Communications Beijing University of Posts and Telecommunications Beijing 100876 China Department of Communications Engineering Tampere University of Technology Tampere PF1-33101 Finland

Systems are always designed and optimized based on full traffic load in the current literatures. However, practical systems are seldom operating at full load, even at peak traffic hours. Instead of maximizing system rate to achieve the full load, an optimal energy-efficient scheme to minimize the transmit power with required rates is investigated in this article. The considered scenario is a two-way relay channel using amplify-and-forward protocol of physical layer network coding, where two end nodes exchange messages via multiple relay nodes within two timeslots. A joint power allocation and relay selection scheme is designed to achieve the minimum transmit power. Through convex optimization theory, we firstly prove that single relay selection scheme is the most energy-efficient way for physical layer network coding. The closed-form expressions of power allocation are also given. Numerical simulations demonstrate the performance of the designed scheme as well as the comparison among different schemes.

关键词： energy-efficient two-way relay channel physical layer network coding power allocation relay selection rate constraints

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基于改进的多元宇宙算法的晶圆生产调度算法

郑州大学学报（理学版） 2024年第6期56卷 77-83页

作者：王银玲师春雪田辉朱晓然曹仰杰卫荣汉郑州大学网络空间安全学院河南郑州450002 郑州大学智能传感研究院河南郑州450002 汉威科技集团股份有限公司河南郑州450001 郑州大学力学与安全工程学院河南郑州450001

针对以最小化最大完工时间为目标的晶圆生产制造系统的调度问题,提出了改进的多元宇宙算法。根据晶圆生产制造系统的特征,构建了一个整数规划模型。针对原始多元宇宙算法的局限性,分别从使用启发式规则生成初始种群、重新定义向最优宇... 详细信息

针对以最小化最大完工时间为目标的晶圆生产制造系统的调度问题,提出了改进的多元宇宙算法。根据晶圆生产制造系统的特征,构建了一个整数规划模型。针对原始多元宇宙算法的局限性,分别从使用启发式规则生成初始种群、重新定义向最优宇宙移动策略和宇宙更新策略三个方面对算法进行改进。将原始多元宇宙算法、遗传算法、NEH启发式算法、迭代贪婪算法以及通过不同策略改进的多元宇宙算法进行对比实验,结果表明,所提方法可以高效地解决晶圆制造过程中的复杂现象。

关键词：晶圆制造多元宇宙算法可重入的混合流水车间调度算法