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Topology awareness algorithm for virtual network mapping

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Journal of Zhejiang university-Science C(Computers and Electronics) 2012年第3期13卷 178-186页

作者： Xiao-ling LI Huai-min WANG Chang-guo GUO Bo DING Xiao-yong LI Wen-qi BI Shuang TAN National Key Laboratory of Parallel and Distributed Processing National University of Defense Technology.Changsha 410073China School of Computer National University of Defense TechnologyChangsha 410073China China Electronic Systems Engineering Corporation Beijing 100039China The northern Institute of Electronic Equipment of China Beijing 100083China

Network virtualization is recognized as an effective way to overcome the ossification of the Internet. However, the virtual network mapping problem (VNMP) is a critical challenge, focusing on how to map the virtual networks to the substrate network with efficient utilization of infrastructure resources. The problem can be divided into two phases: node mapping phase and link mapping phase. In the node mapping phase, the existing algorithms usually map those virtual nodes with a complete greedy strategy, without considering the topology among these virtual nodes, resulting in too long substrate paths (with multiple hops). Addressing this problem, we propose a topology awareness mapping algorithm, which considers the topology among these virtual nodes. In the link mapping phase, the new algorithm adopts the k-shortest path algorithm. Simulation results show that the new algorithm greatly increases the long-term average revenue, the acceptance ratio, and the long-term revenue-to-cost ratio (R/C).

关键词： Network virtualization Ossification Virtual network (VN) mapping Substrate network (SN) Topology awareness Acceptance ratio

Visualization Analysis of Literature on Building Photovoltaic technology Based on CiteSpace

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Journal of Landscape Research 2024年第5期16卷 46-49,55页

作者： WANG Ling LI Haiying university of northern technology Beijing 100144China

With the proposal of the double carbon target,the task of energy saving and emission reduction of buildings has become more *** application of building photovoltaic technology is identified as a significant breakthrough to address this *** this paper,the visual analysis and interpretation of literature on building photovoltaic(PV)technology were conducted by using the Cite Space analysis tool based on a review of Chinese and international literature ***,global research on BIPV technology was summarized and *** paper provides ideas for the future application of building photovoltaic technology by constructing a knowledge map for the application of building photovoltaic technology to help the construction of a low-carbon society.

关键词： Building photovoltaic technology Cite Space Visualized analysis

Bi nanoparticles encapsulated in nitrogen-doped carbon as a long-life anode material for magnesium batteries

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Journal of Magnesium and Alloys 2023年第11期11卷 4181-4188页

作者： Junjun Wang Ruohan Yu Jianxiang Wang Juncai Long Fan Qiao Lei Zhang Guanjie He Qinyou An Liqiang Mai State Key Laboratory of Advanced technology for Materials Synthesis and Processing School of Materials Science and EngineeringWuhan University of TechnologyWuhan 430070China Christopher Ingold Laboratory Department of ChemistryUniversity College London20 Gordon StreetLondon WC1H 0AJUnited Kingdom of Great Britain and Northern IrelandUnited Kingdom Hubei Longzhong Laboratory Wuhan University of Technology(Xiangyang Demonstration Zone)Xiangyang 441000China

Bismuth has garnered significant interest as an anode material for magnesium batteries(MBs) because of its high volumetric specific capacity and low working potential. Nonetheless, the limited cycling performance(≤100 cycles) limits the practical application of Bi as anode for MBs. Therefore, the improvement of Bi cycling performance is of great significance to the development of MBs and is also full of challenges. Here, Bi nanoparticles encapsulated in nitrogen-doped carbon with single-atom Bi embedded(Bi@NC) are prepared and reported as an anode material for MBs. Bi@NC demonstrates impressive performance, with a high discharge capacity of 347.5 mAh g^(-1) and good rate capability(206.4 mAh g^(-1)@500 mA g^(-1)) in a fluoride alkyl magnesium salt electrolyte. In addition, Bi@NC exhibits exceptional long-term stability, enduring 400 cycles at 500 mA g^(-1). To the best of our knowledge, among reported Bi and Bi-based compounds for MBs, Bi@NC exhibits the longest cycle life in this work. The magnesium storage mechanism of Bi@NC is deeply studied through X-ray diffraction, transmission electron microscopy and X-ray photoelectron spectroscopy. This work provides some guidance for further improving the cycling performance of other alloy anodes in MBs.

关键词： Magnesium batteries Bismuth 3D tomography reconstruction Magnesium alloy Single-atom

Delicate scale multipeak and flat-top structures of solitary waves in multicomponent plasmas

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Plasma Science and technology 2017年第3期19卷 42-46页

作者： Ding LU Ziliang LI Haibo SANG Baisong XlE College of Nuclear Science and technology Beijing Normal University Beijing 100875 People's Republic of China Middle School Northern Jiaotong University Beijing 100081 People's Republic of China Beijing Radiation Center Beijing 100875 People's Republic of China

Numerically the delicate scale multipeak structures of the electrostatic solitary waves are found for the three-component（electron-positron-ion,i.e.,EPI） *** complicated homoclinic phase portraits for this two-degree-of-freedom system are presented,which indicate that the system exhibits more abundant nonlinear *** finding is very useful to unveil the coherent dynamical behavior in laser-plasma *** has an implication of electron acceleration by a laser with soliton wave mechanism.

关键词： solitary wave electron-positron-ion plasma laser-plasma interaction physics

The Topology Sampling of H2SO4·NH3 with Meta-Dynamics Method

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Computers, Materials & Continua 2019年第8期61卷 701-710页

作者： Yugai Huang Yu Shang Wenqing Li Jiajing He Hairong Zhou Bin Gu Jiangsu Key Laboratory for Optoelectronic Detection of Atmosphere and Ocean Nanjing University of Information Science and TechnologyNanjing210044China Department of Chemistry Jiangsu Second Normal UniversityNanjing210013China Queen’s university BelfastNorthern IrelandBelfast BT71NNUK School of Applied Meteorology Nanjing University of Information Science and TechnologyNanjing210044China

The configurations of molecular clusters have significant impacts on their growth into fine particles in *** this paper,we explore the topology space of the structure of H2SO4·NH3 dimer with a novel sampling technique of meta-dynamics(MTD)method and ab initio molecular dynamics *** simulations are carried out at the temperatures of both 50 K and 242 K,which represent the typical high and low latitudes of *** results show that,compared with only traditional MD simulations,the structure samplings are significantly accelerated with MTD ***,more isomers of the dimer are discovered within the same simulation time *** addition,the results show that MTD is more efficient for circumstances with high temperature.

关键词： Structure sampling H2SO4 and NH3 meta-dynamics acceleration temperature effects

Rollback reconstruction for TDC enhanced perfusion imaging

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Nuclear Science and Techniques 2021年第8期32卷 23-33页

作者： Jia-Shun Liu Yi-Kun Zhang Hui Tang Li-Bo Zhang Ben-Qiang Yang Ying Yan Li-Min Luo Yang Chen Laboratory of Image Science and technology Southeast UniversityNanjing 210096China Department of Radiology General Hospital of the Northern Theater of the Chinese People’s Liberation ArmyShenyang 110016China Department of Radiotherapy General Hospital of the Northern Theater of the Chinese People’s Liberation ArmyShenyang 110016China Centre de Recherche en Information Biomedicale SinoFrancais(LIA CRIBs) 35000 RennesFrance

Tomographic perfusion imaging is a significant imaging modality for stroke ***,the low rotational speed of the C-arm(6–8 s per circle)is a challenge for applying perfusion imaging in C-arm cone beam computed tomography(CBCT).Traditional reconstruction methods cannot remove the artifacts caused by the slow rotational speed or acquire enough sample points to restore the time density curve(TDC).This paper presents a dynamic rollback reconstruction method for *** proposed method can improve the temporal resolution by increasing the sample points used for calculating the *** with existing techniques,the algorithm allows slow-rotating scanners to be used for perfusion imaging *** the experiments,the proposed method was compared with other dynamic reconstruction algorithms based on standard reconstruction and the temporal interpolation *** presented algorithm could improve the temporal resolution without increasing the X-ray exposure time or contrast agent.

关键词： Rollback reconstruction CBCT Time resolution Time density curve

Hybrid Malware Variant Detection Model with Extreme Gradient Boosting and Artificial Neural Network Classifiers

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Computers, Materials & Continua 2023年第9期76卷 3483-3498页

作者： Asma A.Alhashmi Abdulbasit A.Darem Sultan M.Alanazi Abdullah M.Alashjaee Bader Aldughayfiq Fuad A.Ghaleb Shouki A.Ebad Majed A.Alanazi Department of Computer Science Northern Border UniversityArar9280Saudi Arabia Department of Computer Sciences Faculty of Computing and Information TechnologyNorthern Border UniversityRafha91911Saudi Arabia Department of Information Systems College of Computer Science and InformationJouf UniversitySakakaAljoufSaudi Arabia School of Computing University Teknologi Malaysia81310 UTM Johor BahruJohor81310Malaysia Department of Computer and Electronic Engineering Sana’a Community CollegeSana’a5695Yemen

In an era marked by escalating cybersecurity threats,our study addresses the challenge of malware variant detection,a significant concern for amultitude of sectors including petroleum and mining *** paper presents an innovative Application Programmable Interface(API)-based hybrid model designed to enhance the detection performance of malware *** model integrates eXtreme Gradient Boosting(XGBoost)and an Artificial Neural Network(ANN)classifier,offering a potent response to the sophisticated evasion and obfuscation techniques frequently deployed by malware *** model’s design capitalizes on the benefits of both static and dynamic analysis to extract API-based features,providing a holistic and comprehensive view of malware *** these features,we construct two XGBoost predictors,each of which contributes a valuable perspective on the malicious activities under *** outputs of these predictors,interpreted as malicious scores,are then fed into an ANN-based classifier,which processes this data to derive a final *** strength of the proposed model lies in its capacity to leverage behavioral and signature-based features,and most importantly,in its ability to extract and analyze the hidden relations between these two types of *** efficacy of our proposed APIbased hybrid model is evident in its performance *** outperformed other models in our tests,achieving an impressive accuracy of 95%and an F-measure of 93%.This significantly improved the detection performance of malware variants,underscoring the value and potential of our approach in the challenging field of cybersecurity.

关键词： API-based hybrid malware detection model static and dynamic analysis malware detection

Recent advances in the application of metal organic frameworks using in advanced oxidation progresses for pollutants degradation

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Chinese Chemical Letters 2022年第12期33卷 5013-5022页

作者： Heshan Zheng Yunying Hou Shuo Li Jun Ma Jun Nan Tong Li College of Chemistry and Chemical Engineering Qiqihar UniversityQiqihar 161006China Urban Water Resources Development and northern National Engineering Research Center Harbin 150090China School of Environment Harbin Institute of TechnologyHarbin 150090China School of Energy and Environmental Engineering University of Science and Technology BeijingBeijing 100083China

Metal-organic frameworks(MOFs)materials with highly ordered and porous crystalline structure,have excellent performance in advanced oxidation progresses(AOPs)for organic contaminants degradation in water *** review intends to summarize the timely references and insights for the recent advances in MOFs that are used in *** with the preparation methodologies,including conventional hydrothermal method,electrochemical method,sol-gel method,and emerging microwave and ultrasound assisted synthesis *** and mechanism for MOFs using in various AOPs of Fenton-like,photocatalysis,catalytic ozonation,persulfate catalysis and other emerging oxidation methods are emphatically *** hope this review can comprehensively summarize the research and application progress of MOFs in AOPs,deepen the understanding of the catalytic mechanisms.

关键词： Advanced oxidation progresses Metal-organic frameworks Contaminants degradation Synthesis methods Catalysis mechanism

Initiation of ice jam in front of bridge piers-An experimental study

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Journal of Hydrodynamics 2019年第1期31卷 117-123页

作者： Jun Wang Jian Hua Pang-pang Chen Jueyi Sui Peng Wu Todd Whitcombe College of Civil and Hydraulic Engineering Hefei University of TechnologyHefei 230009China Modern Green Development Co.LTD Beijing 100028China Environmental Sciences and Engineering Program University of Northern British ColumbiaPrince GeorgeBCCanada Environmental System Engineering Program University of ReginaReginaCanada

The presence of bridge piers in natural rivers significantly changes the flow and boundary *** a consequence,ice jams can often be initiated in front of bridge *** the changes in flow conditions,two types of ice jam formation may appear:surface accumulation of ice blocks (surface ice blockage) and thickened accumulation of ice blocks (vertical ice blockage).In the present study,the initiation process of ice jam was studied based on *** is found that the critical ice concentration for ice jam blockage depends on the ice block dimension,channel opening and flow *** surface blockage conditions,a larger ratio of ice cube dimension to channel opening (between piers) can result in a smaller critical ice concentration for ice jam blockage,which has no obvious relation with flow *** vertical blockage conditions,the critical ice concentration for ice jam blockage increases with flow Froude number and decreases with the ratio of ice dimension to channel opening (between piers).Based on experiments conducted in laboratory,equations for determining critical ice concentration for these two types of ice jam blockage have been developed.

关键词： Bridge piers surface ice blockage vertical ice blockage critical ice concentrations