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Study on the performance of the A*Prune QoS routing algorithm for intelligent optical networks and its improvements

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The Journal of China Universities of Posts and Telecommunications 2006年第3期13卷 65-70页

作者： SUN Quan wang gong-pu School of Telecommunication Engineering Beijing University of Posts and Telecommunications Beijing 100876 China School of Network Education Beijing University of Pos'ts and TelecommunicationsBeijing 100088 China

The A＇Prune quality of service （QoS） routing algorithm was proposed to compute K-shortest paths satisfying multiple QoS constraints, The A＇Prune is considered to be one of the practical routing algorithms for intelligent optical networks because of its flexibility in handling many practical constraints, This article gives detailed performance studies of the algorithm through extensive simulation experiments. We found that both the running time and the memory space requirements of the algorithm are large, especially when the network size increases, in this article, we also propose an approach to improving the performance of the A＇Prune algorithm. The improvements should make the A＇Prune algorithm more attractive for practical use in intelligent optical networks.

关键词： constrained paths K-shortest paths QoS routing,intelligent optical networks

Condensation reaction of formaldehyde and methyl formate catalyzed by a composite catalyst system

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Chinese Chemical Letters 2007年第7期18卷 811-813页

作者： Ke Bing wang gong Ying wang Chengdu Institute of Organic Chemistry Chinese Academy of Sciences Chengdu 610041 China Graduate School of Chinese Academy of Sciences Beijing 100039 China

The condensation reaction of formaldehyde and methyl formate to form methyl glycolate and methyl methoxy acetate catalyzed by p-toluenesulfonic acid and different Lewis acid compounds has been investigated. The composite catalytic system consisting of p-toluenesulfonic acid and NiX2 （X = Cl, Br, I）, especially NiI2, exhibited a high catalytic performance for the condensation reaction, the total yield of MG and MMAc was up to 72.37%.

关键词： p-Toluenesulfonic acid Formaldehyde Methyl formate Methyl glycolate Methyl methoxy acetate

A New Load Balancing Scheme on Heterogeneous Database Cluster

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Geo-Spatial Information Science 2006年第3期9卷 216-222页

作者： gong Weihua wang Yuanzhen College of Computer Science and Technology Huazhong University of Science and Technology Guanshan Wuhan 430074 China.

In heterogeneous database cluster, the performance of load balancing is closely related to the computing capabilities of heterogeneous nodes and the different types of workloads. Thus, a method is introduced to evaluate the load status of nodes by the weighted load values with consideration of both the utilization of different resources and the workload types in a load balaneer and an efficient and dynamic load balancing scheme is proposed for OLTP（online transaction processing） workloads to maximize the utilization of distributed resources and achieve better performance, which need not collect the feedback of load information from the lower nodes and effectively keeps from the data skew. The simulation results for OLTP services gained by TPC-C tool show that the dynamic weighted balancing policy leads to sub-linear throughput speedup and keeps the heterogeneous cluster well balanced.

关键词： heterogeneous cluster OLTP load balancing

Synthesis of Chlorogenic Acid Imprinted Chromatographic Packing by Surface-initiated Atom Transfer Radical Polymerization and Its Application

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Chemical Research in Chinese Universities 2014年第5期30卷 855-862页

作者： NIU Yuling MA Meihua gong Yanru wang Yue gong Bolin Key Laboratory of Energy and Chemical Engineering Ningxia University Yinchuan 750021 P. R. China

A novel chromatographic packing of chlorogenic acid（CGA） molecularly imprinted polymer（MIP） based on the 5.0 ~tm silica was prepared by surface initiated atom transfer radical polymerization（SI-ATRP） with 4-vinylpyridine（4-VP） as functional monomer, ethyl glycol dimethacrylate（EDMA） as cross-linker in the mixture of methanol and water（7：3, volume ratio） under mild reaction conditions. The characteristics of CGA MIP were investi- gated by elemental analysis, thermogravimetric analysis（TGA）, Fourier transform infrared spectrometry（FTIR） and atomic force microscopy（AFM）. The effects of some chromatographic conditions such as mobile phase composition and temperature on the retention time were investigated. The adsorption capacity of the stationary phase for com- pounds was determined by frontal chromatographic technique. The results show that Freundlich isotherm fits the ex- perimental adsorption isotherm data better than Langmuir model does. The relatively high heterogeneity index values regressed with the Freundlich isotherm suggest the formation of fairly homogeneous MIP. Thermodynamic data（AAH and AAS） obtained by van＇t Hoff plots reveal an entropy-controlled separation. The CGA MIP column was shown to be successful for the separation and purification of chlorogenic acid from the extract of Honeysuckle.

关键词： Molecularly imprinted chromatographic packing Chlorogenic acid Surface initiated atom transfer radical polymerization Honeysuckle

A Novel Packet Marking Algorithm in Context-aware Autonomic QoS Framework

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China Communications 2009年第4期6卷 98-107页

作者： gong Xiangyang wang Wendong Li Yan State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications 100876 Beijing P.R. China

Autonomic networking is one of the hot research topics in the research area of future network *** this paper, we introduce context-aware and autonomic attributes into DiffServ QoS framework, and propose a novel autonomic packet marking(APM) *** the proposed autonomic QoS framework, APM is capable of collecting various QoS related contexts, and adaptively adjusting its behavior to provide better QoS guarantee according to users' requirements and network *** results show that APM provides better performance than traditional packet marker, and significantly improves user's quality of experience.

关键词： autonomic QoS framework DiffServ context-aware packet marking

On the Second Smallest and the Largest Normalized Laplacian Eigenvalues of a Graph

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Acta Mathematicae Applicatae Sinica 2021年第3期37卷 628-644页

作者： Xiao-guo TIAN Li-gong wang You LU Department of Applied Mathematics School of ScienceNorthwestern Polytechnical UniversityXi'an 710072China Xi'an-Budapest Joint Research Center for Combinatorics Northwestern Polytechnical UniversityXi'an 710129China

Let G be a simple connected graph with order *** L(G)and Q(G)be the normalized Laplacian and normalized signless Laplacian matrices of G,***λk(G)be the k-th smallest normalized Laplacian eigenvalue of *** byρ(A)the spectral radius of the matrix *** this paper,we study the behaviors ofλ2(G)andρ(L(G))when the graph is perturbed by three *** also study the properties ofρ(L(G))and X for the connected bipartite graphs,where X is a unit eigenvector of L(G)corresponding toρ(L(G)).Meanwhile we characterize all the simple connected graphs withρ(L(G))=ρ(Q(G)).

关键词： second smallest normalized Laplacian eigenvalue normalized Laplacian spectral radius normalized signless Laplacian spectral radius

Commentary on “Experimental study on the moving characteristics of fine grains in wide grading unconsolidated soil under heavy rainfall” by CUI Yi-fei, ZHOU Xiao-jun and GUO Chao-xu

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Journal of Mountain Science 2018年第4期15卷 918-920页

作者： wang gong-hui JIANG Yao Disaster Prevention Research Institute Kyoto University Key Laboratory of Mountain Hazards and Earth Surface Process/Institute of Mountain Hazards and Environment Chinese Academy of Sciences (CAS)

A paper, which was recently published in Journal of Mountain Science by Cui et al.(2017), reported a series of laboratory flume experiments designed to illuminate the moving characteristics of fine particles for wide grading unconsolidated soils by considering three factors, slope gradient, rainfall duration and rainfall intensity. This commentary is prompted to further provide some viewpoints about the fine particle migration phenomenon during landslide initiation and offer some recommendations as the future research focus for better understanding the related processes.

关键词：降雨评论特征试验性 CUI 学习谷物土壤

Synthesis of Poly(isosorbide carbonate) via Melt Polycondensation Catalyzed by Ca/SBA-15 Solid Base

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Chinese Journal of Polymer Science 2018年第9期36卷 1027-1035页

作者： Xiao-Long Shen Zi-Qing wang Qing-Yin wang Shao-Ying Liu gong-Ying wang Chengdu Institute of Organic Chemistry Chinese Academy of Sciences Chengdu 610041 China University of Chinese Academy of Sciences Beijing 100049 China Changzhou Institute of Chemistry Changzhou 213164 China

Ca/SBA-15 solid bases with different Ca/Si atomic ratios were prepared by a one-pot route and employed as catalysts for the production of poly（isosorbide carbonate）（PIC） from diphenyl carbonate and isosorbide via a transesterification polymerization process. The relationship between physicochemical properties and catalytic performance for Ca/SBA-15 in this melt process was investigated by means of various characterization techniques. It was found that basic site amount and strength were responsible for this transesterification process; the weak and medium basic sites inclined to promote polycondensation reaction. It was worth noting that strong basic sites could favor the decomposition of the resultant P/C, resulting in the decrease of weight-average molecular weight （Mw） and yield, and the sample with Ca/Si atomic ratio of 0.4 exhibited the best catalytic performance, giving PIC with Mw of 4.88 × 10^4 g/mol and Tg of 169 ℃ at the optimal conditions. This excellent activity can be ascribed to the presence of rich basic sites and specific basic strength on the surface of 0.4Ca/SBA-15.

关键词： Ca/SBA-15 Poly(isosorbide carbonate) Diphenyl carbonate Transesterification Basic sites

Coherence resonance and bi-resonance by time-periodic coupling strength in Hodgkin-Huxley neuron networks

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Science China Chemistry 2012年第2期55卷 256-261页

作者： LIN Xiu gong YuBing wang Li MA XiaoGuang School of Physics Ludong University Yantai 264025 China

We study the effect of time-periodic coupling strength on the spiking coherence of Newman-Watts networks of Hodgkin-Huxley(HH) neurons with non-Gaussian *** is found that the spiking can exhibit coherence resonance(CR) when the extent of deviation of non-Gaussian noise from Gaussian noise and the amplitude of the coupling strength are *** particular,coherence bi-resonance(CBR) is observed when the frequency of the coupling strength is varied,and the CBR is always observed when the frequency is equal to,or a multiple of,the spiking period,manifesting as the locking between the frequencies of the spiking and the coupling *** results show that a time-periodic coupling strength may play a more constructive and efficient role in enhancing the spiking coherence of the neuronal networks than a constant coupling *** findings provide insight into the role of time-periodic coupling strength for enhancing the time precision of information processing in neuronal networks.

关键词： neuronal network time-periodic coupling strength coherence resonance and bi-resonance non-Gaussian noise