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RMAC： A Reliable MAC Protocol Supporting Multicast for Wireless Ad Hoc Networks

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Journal of Computer Science & Technology 2005年第5期20卷 702-712页

作者： wei-Sheng si Cheng-Zhi Li School of Software Dalian University of Technology P.R. China Department of Computer Science and Engineering University of Texas at Arlington U.S.A.

This paper presents a new reliable MAC protocol called “RMAC”supporting reliable multicast for wireless ad hoc networks. By utilizing the busy tones to realize the multicast reliability, RMAC has three novelties：（1） it uses a variablelength control frame to stipulate an order for the receivers to respond, thus solving the feedback collision problem; （2） it extends the usage of busy tone for preventing data frame collisions into the multicast scenario; and （3） it introduces a new usage of busy tone for acknowledging data frames positively. In addition, RMAC is generalized into a comprehensive MAC protocol that provides both reliable and unreliable services for all the three modes of communications： unicast, multicast, and broadcast, making it capable of supporting various upper-layer protocols. The evaluation shows that RMAC achieves high reliability with very limited overhead. RMAC is also compared with other reliable MAC protocols, showing that RMAC not only provides higher reliability but also involves lower cost.

关键词： wireless ad hoc network medium access control reliable multicast busy tone

成渝地区双城经济圈旅游共生水平测度及协同发展研究

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四川师范大学学报（自然科学版） 2025年第1期48卷 94-104页

作者：司嵬樊丹王冲四川旅游学院旅游文化产业学院四川成都610100 四川旅游学院大数据与统计学院四川成都610100 四川旅游学院文旅融合发展研究中心四川成都610100

基于共生理论和社会网络分析,从成渝地区旅游同质度、关联度、外向功能强度3个维度测评并分析成渝地区双城经济圈旅游业共生水平现状.通过分析得出:成渝地区双城经济圈旅游业的同质度和重合度均较高,成都市、重庆主城区、渝西毗邻片区3... 详细信息

基于共生理论和社会网络分析,从成渝地区旅游同质度、关联度、外向功能强度3个维度测评并分析成渝地区双城经济圈旅游业共生水平现状.通过分析得出:成渝地区双城经济圈旅游业的同质度和重合度均较高,成都市、重庆主城区、渝西毗邻片区3个片区处于成渝双城经济圈旅游共生的中心主导地位,成都是连接四川省其他地区和重庆片区的桥梁.广安市、达州市、资阳市与重庆地区虽联系较多,但是外向功能强度不高,还未发挥出旅游的带动和桥梁作用.成渝地区双城经济圈中旅游关系存在4个子群,重庆地区与川南地区子群具有较强的影响力,川东北与重庆毗邻地区是最具潜力子群.据此,从建立分工基础上的对称互惠一体化共生模式、营造良好的旅游市场一体化共生环境、打破行政区划创造多元旅游共生界面3个方面提出成渝地区双城经济圈旅游共生发展的对策建议.

关键词：成渝双城经济圈旅游共生社会网络分析区域协同

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The Thickness of Some Complete Bipartite and Tripartite Graphs

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Acta Mathematicae Applicatae sinica 2024年第4期40卷 1001-1014页

作者： si-wei HU Yi-chao CHEN Yali Peicui School Changsha 410021China School of Mathematics Suzhou University of Science and TechnologySuzhou 215009China

In this paper,we obtain the thickness for some complete k-partite graphs for k=2,*** first compute the thickness of K_(n,n+8)by giving a planar decomposition of K_(4k-1,4k+7)for k≥***,two planar decompositions for K_(1,g,g)(g-1)when g is even and for K^(1,g,1/2(g-1)2)when g is odd are *** a recursive construction,we also obtain the thickness for some complete tripartite *** results here support the long-standing conjecture that the thickness of K_(m,n)is[mn/2(m+n-2)]for any positive integers m,n.

关键词： thickness complete bipartite graph complete tripartite graph planar decomposition

Glass capillary nanopore for single molecule detection

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Science China(Technological Sciences) 2015年第5期58卷 803-812页

作者： SHA JingJie si wei XU wei ZOU YiRen CHEN YunFei Jiangsu Key Laboratory for Design and Manufacture of Micro-Nano Biomedical Instruments Southeast University School of Mechanical Engineering Southeast University

single molecule detection based on nanopore technology is a very promising approach for medical diagnostics, drug therapy and even DNA sequencing. Compared with other biological nanopores and solid-state nanopores, the glass capillary nanopore has low cost, easy availability and stable mechanical characteristics, thus it has been widely used in the nanopore technology for single molecule detection. In this review, we will focus on the studies of the glass nanopore sensors. The popular glass nanopore fabrication methods would be introduced, and the applications of glass nanopores in the detection of nanoparticles, proteins and DNA molecules would be presented. We hope this review will help widen field of vision and promote the development of the nanopore technology based on the glass capillary nanopores.

关键词： fabrication capillary nanotubes sequencing diameters SWNTs DNA etching diagnostics nanometer

Measuring the beaming angle of GRB 030329 by fitting the rebrightenings in its multiband afterglow

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Research in Astronomy and Astrophysics 2010年第11期10卷 1119-1126页

作者： wei Deng Yong-Feng Huang si-wei Kong Department of Astronomy Nanjing University Nanjing 210093 China Key Laboratory of Modern Astronomy and Astrophysics （Nanjing Univ.） Ministry of EducationNanjing 210093 China

Multiple rebrightenings have been observed in the multiband afterglow of GRB 030329. In particular, a marked and quick rebrightening occurred at about t 1.2 × 10^5 s. Energy injection from late and slow shells seems to be the best interpretation for these rebrightenings. Usually it is assumed that the energy is injected into the whole external shock. However, in the case of GRB 030329, the rebrightenings are so quick that the usual consideration fails to give a satisfactory fit to the observed light curves. Actually, since these late/slow shells freely coast in the wake of the external shock, they should be cold and may not expand laterally. The energy injection then should only occur at the central region of the external shock. Considering this effect, we numerically re-fit the quick rebrightenings observed in GRB 030329. By doing this, we were able to derive the beaming angle of the energy injection process. Our result, with a relative residual of only 5% - 10% during the major rebrightening, is bet- ter than any previous modeling. The derived energy injection angle is about 0.035. We assume that these late shells are ejected by the central engine via the same mechanism as those early shells that produce the prompt gamma-ray burst. The main difference is that their velocities are much slower, so that they catch up with the external shock relatively late and are manifested as the observed quick rebrightenings. If this were true, then the derived energy injection angle can give a good measure of the beaming angle of the prompt γ-ray emission. Our study may hopefully provide a novel method to measure the beaming angle of gamma-ray bursts.

关键词： gamma-rays bursts-ISM jets and outflows

Prediction of the Charpy V-notch impact energy of low carbon steel using a shallow neural network and deep learning

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International Journal of Minerals,Metallurgy and Materials 2021年第8期28卷 1309-1320页

作者： si-wei Wu Jian Yang Guang-ming Cao State Key Laboratory of Advanced Special Steel School of Materials Science and EngineeringShanghai UniversityShanghai 200444China State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819China

The impact energy prediction model of low carbon steel was investigated based on industrial data. A three-layer neural network, extreme learning machine, and deep neural network were compared with different activation functions, structure parameters, and training functions. Bayesian optimization was used to determine the optimal hyper-parameters of the deep neural network. The model with the best performance was applied to investigate the importance of process parameter variables on the impact energy of low carbon steel. The results show that the deep neural network obtains better prediction results than those of a shallow neural network because of the multiple hidden layers improving the learning ability of the model. Among the models, the Bayesian optimization deep neural network achieves the highest correlation coefficient of 0.9536, the lowest mean absolute relative error of 0.0843, and the lowest root mean square error of 17.34 J for predicting the impact energy of low carbon steel. Among the variables, the main factors affecting the impact energy of low carbon steel with a final thickness of7.5 mm are the thickness of the original slab, the thickness of intermediate slab, and the rough rolling exit temperature from the specific hot rolling production line.

关键词： prediction shallow neural network deep neural network impact energy low carbon steel

Separation of growth-stimulating peptides for Bifidobacterium from soybean conglycinin

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World Journal of Gastroenterology 2005年第37期11卷 5801-5806页

作者： wei-Yong Zuo wei-Hua Chen si-Xiang Zou Key Laboratory of Animal Physiology and Biochemistry Ministry of Agriculture College of Veterinary Medicine Nanjing Agricultural University Nanjing 210095 Jiangsu Province China

AIM： To isolate and identify the soybean conglycinin peptides that selectively stimulates the growth of bifidobacteria in vitro, and to investigate the effect of soybean conglycinin peptides on intestinal ecosystem in vivo. METHODS： Soybean conglycinin was purified from soybean seeds by gel filtration （Sepharose-CL-6B）. These proteins were submitted to hydrolysis by pepsin. Several growth-stimulating peptides for bifidobacteria were isolated chromatographically from pepsin hydrolysis of soybean conglycinin and identified by means of matrixassisted laser desorption ionization time of flight mass spectrometry （MALDI-TOF-MS）. Parallel to in vitro study, in vivo experiments with soybean conglycinin peptides were performed in mice. Ninety male KM mice were randomly assigned into five groups of 16 mice each, and each group was administered for 21d intragastrically with physiological saline （control）, conglycinin, pepsin-treated conglycinin （PTC）, the most active fraction which isolated from pepsin-treated conglycinin （P2-PTC） and HCl-full hydrolysis of conglycinin （HCl-FHC）, respectively. Intestinal microflora were evaluated by standard microbiologic methods and biochemical assays of cecal content samples after treatment. RESULTS： The results showed that the peptides which were isolated from soybean conglycinin could stimulate the growth of bifidobacteria in vitro, and the molecular mass of purified peptides with MALDI-TOF-MS ranged from 693.32 to 1829.55. Compared with control group, in vivo experiments showed that P2-PTC group decreased cecal pH （7.08±0.08 vs7.21±0.09, P〈0.05） and enterococcicounts （5.38±0.26 log10CFU/g vs 5.78±0.19 log10CFU/g, P〈0.05）, significantly increased sigA level （172.08±35.40 ng/g vs 118.27±33.93 ng/g, P〈0.01） and β-galactosidase activity （1.28±0.23 U/g vs 1.82±0.58 U/g, P〈0.05） CONCLUsiON： The results have shown that conglycinin is good source for enzyme-mediated production of peptides which stimulate the growth of bifidobacteria. These peptid

关键词： Conglycinin pepsin peptides bifidobacteria

TRIPLET combined with microwave ablation:A novel treatment for advanced hepatocellular carcinoma

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World Journal of Gastrointestinal Oncology 2025年第1期17卷 10-12页

作者： Fei-Yu Zhao Guo-wei si Nian-Song Qian Department of Thoracic Oncology Respiratory and Critical Care MedicineThe Eighth Medical Center of People’s Liberation Army General HospitalBeijing 100853China Department of Gastroenterology Fourth Medical CentreGeneral Hospital of the People's Liberation ArmyBeijing 100142China Senior Department of Thoracic Oncology Respiratory and Critical Care MedicineThe Eighth Medical Center of People’s Liberation Army General HospitalBeijing 100091China

This editorial comments on a study by Zuo et *** focus is on the efficacy of he-patic arterial infusion chemotherapy combined with camrelizumab and apatinib(the TRIPLET regimen),alongside microwave ablation therapy,in treating advanced hepatocellular carcinoma(HCC).The potential application of this combination therapy for patients with advanced HCC is evaluated.

关键词： Microwave ablation Hepatic arterial infusion chemotherapy Apatinib Camrelizumab Hepatocellular carcinoma

A review of nuclear magnetic resonance(NMR) technology applied in the characterization of polymer gels for petroleum reservoir conformance control

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Petroleum Science 2021年第6期18卷 1760-1775页

作者： Dao-Yi Zhu Zhi-Hua Deng si-wei Chen State Key Laboratory of Petroleum Resources and Prospecting and Petroleum School China University of Petroleum-Beijing at KaramayKaramay834000XinjiangChina

Polymer gel systems have been widely applied to control excessive water and improve oil recovery(IOR)in petroleum *** are usually divided into two main types,in-situ cross-linked polymer gels,and pre-formed polymer *** recent years,nuclear magnetic resonance(NMR) technology has been gradually applied to the research of polymer gel systems due to its unique analysis *** paper is intent to review these works *** in-situ cross-linked polymer gel systems,NMR can be used to characterize the chemical structure changes of the polymer,the cross-linker,and the auxiliary agent in the formulation of the polymer gel ***,the gelation time and the gel strength of the in-situ cross-linked polymer gel systems can also be measured by *** pre-formed polymer gels,NMR can be employed to detect the chemical structure of the designed ***,the NMR method can evaluate the plugging,water control,and oil improvement performance of the polymer gels in porous media without using *** review can help readers build a more systematic understanding of the application of NMR technology in polymer gel systems for IOR and help re searchers to more deeply study the performance of polymer gel systems.

关键词： Nuclear magnetic resonance Polymer gels Gelation time Gel strength Conformance control