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Dynamic threshold for SPWVD parameter estimation based on Otsu algorithm

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Journal of Systems Engineering and Electronics 2013年第6期24卷 919-924页

作者： Ning Ma jianxin wang School of Electronic Engineering and Optoelectronic Technology Nanjing University of Science and Technology

Time-frequency-based methods are proven to be effective for parameter estimation of linear frequency modulation （LFM） signals. The smoothed pseudo Winger-Ville distribution （SPWVD） is used for the parameter estimation of multi-LFM signals, and a method of the SPWVD binarization by a dynamic threshold based on the Otsu algorithm is proposed. The proposed method is effective in the demand for the estimation of different parameters and the unknown signal-to-noise ratio （SNR） circumstance. The performance of this method is confirmed by numerical simulation.

关键词： parameter estimation smoothed pseudo Winger-Ville distribution (SPWVD) dynamic threshold Otsu algorithm

FPC: A New Approach to Firewall Policies Compression

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Tsinghua Science and Technology 2019年第1期24卷 65-76页

作者： Yuzhu Cheng Weiping wang jianxin wang Haodong wang the School of Information Science and Engineering Central South University the School of Software Changsha Social work College the Department of Electrical Engineering and Computer Science Cleveland State University

Firewalls are crucial elements that enhance network security by examining the field values of every packet and deciding whether to accept or discard a packet according to the firewall policies. With the development of networks, the number of rules in firewalls has rapidly increased, consequently degrading network *** addition, because most real-life firewalls have been plagued with policy conflicts, malicious traffics can be allowed or legitimate traffics can be blocked. Moreover, because of the complexity of the firewall policies, it is very important to reduce the number of rules in a firewall while keeping the rule semantics unchanged and the target firewall rules conflict-free. In this study, we make three major contributions. First, we present a new approach in which a geometric model, multidimensional rectilinear polygon, is constructed for the firewall rules compression ***, we propose a new scheme, Firewall Policies Compression(FPC), to compress the multidimensional firewall rules based on this geometric model. Third, we conducted extensive experiments to evaluate the performance of the proposed method. The experimental results demonstrate that the FPC method outperforms the existing approaches, in terms of compression ratio and efficiency while maintaining conflict-free firewall rules.

关键词： firewall firewall policy network security firewall rules compression

Editorial for biomimetic nanoparticles for drug delivery

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Acta Pharmaceutica Sinica B 2018年第1期8卷 2-3页

作者： jianxin wang Department of Pharmaceutics School of PharmacyFudan University

The origins of controlled release drug delivery could be dated back to the *** Spansule technology was developed to deliver a drug for 12 h in *** with taking a drug every 6 h or every8 h,twice-a-day formulation was revolutionary in improving the patients’compliance and *** then,advances in drug delivery technologies have introduced numerous formulations

关键词： Editorial for biomimetic nanoparticles for drug delivery PGP

Reconsideration of the origins of the pastoral nomadic economy in the Eurasian Steppe

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Science China Earth Sciences 2022年第11期65卷 2057-2067页

作者： jianxin wang Chen DENG Xiang WAN Central for Silk Road Archaeology Northwest UniversityXi'an 710127China School of Culural Heritage Northwest UniversityXi'an710127China Institute of Silk Road Studies Northwest UniversityXi'an 710069China

Archaeological discoveries indicate that a variety of economic models have operated in the inland areas of *** of these models,pastoral nomadism,differs from agriculture,agro-pastoral,and settled pastoralism in terms of cattle-breeding,cultivation and *** nomadism is a livestock-breeding management mode of production,in which the stock is fed by uninterrupted moving in a large geographical *** Eurasian Steppe,which includes the cold forest-steppe area in the north and the semi-arid desert-steppe in the south,is the major region in which the ancient nomadic population *** of the absence of both intrinsic motivation and external pressure for the transition to pastoral nomadism,early animal husbandry economy in the forest-steppe area could not have developed into the initial pastoral nomadic economy;instead,the pastoral nomadic economy emerged from the agro-pastoral economy in the semi-arid *** agro-pastoral people were forced to minimize the scale of agriculture and sedentary pastoralism and to turn to a nomadic lifestyle,with the internal cause being a shortage of feed resources caused by expansion of the human population and livestock,with the added external pressure of climatic and environmental *** archaeological findings,the eastern Tianshan area in Xinjiang,China,was a major region for the emergence of the early pastoral nomadic *** main evidence for this conclusion is a series of pastoral nomadic settlement sites in the northern and southern piedmonts of the Tianshan Mountains,which display settlement conditions,resources and environments entirely different from those of agricultural and agro-pastoral settlements elsewhere.

关键词： Eurasian Steppe Origins of pastoral nomadic economy Semi-arid desert-steppe Eastern Tianshan Mountains Nomadic settlements

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Framework to Identify Protein Complexes Based on Similarity Preclustering

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Tsinghua Science and Technology 2017年第1期22卷 42-51页

作者： Xiaoqing Peng Xiaodong Yan jianxin wang the School of Information Science and Engineering Central South UniversityChangsha 410083China

Proteins interact with each other to form protein complexes, and cell functionality depends on both protein interactions and these complexes. Based on the assumption that protein complexes are highly connected and correspond to the dense regions in Protein-protein Interaction Networks（PINs）, many methods have been proposed to identify the dense regions in PINs. Because protein complexes may be formed by proteins with similar properties,such as topological and functional properties, in this paper, we propose a protein complex identification framework（KCluster）. In KCluster, a PIN is divided into K subnetworks using a K-means algorithm, and each subnetwork comprises proteins of similar degrees. We adopt a strategy based on the expected number of common neighbors to detect the protein complexes in each subnetwork. Moreover, we identify the protein complexes spanning two subnetworks by combining closely linked protein complexes from different subnetworks. Finally, we refine the predicted protein complexes using protein subcellular localization information. We apply KCluster and nine existing methods to identify protein complexes from a highly reliable yeast PIN. The results show that KCluster achieves higher Sn and Sp values and f-measures than other nine methods. Furthermore, the number of perfect matches predicted by KCluster is significantly higher than that of other nine methods.

关键词： protein complex similarity preclustering protein-protein interaction networks K-means

Improved kernels for triangle packing in tournaments

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Science China(Information Sciences) 2023年第5期66卷 100-113页

作者： Hanchun YUAN Qilong FENG jianxin wang School of Computer Science and Engineering Central South University Hunan Provincial Key Lab on Bioinformatics Central South University

Triangle packing problem has been paid lots of attention to in the literature. In this paper, we study the kernelization of the triangle packing problem in tournaments. For the parameterized arc-disjoint triangle packing problem in tournaments, we find a maximal arc-disjoint triangle packing with the number of vertices bounded by 2.5k. Based on the relation between the maximal arc-disjoint triangle packing and the vertices outside of the packing, a kernel of size 3.5k for the problem is obtained, improving the previous best one 6k. For the parameterized vertex-disjoint triangle packing problem in sparse tournaments, several new properties between the triangles in maximal vertex-disjoint triangle packing and the arcs in the feedback arc set are presented, which result in a kernel of size 7k for the problem, improving the previous best one of *** also give a 7k vertex kernel for the parameterized feedback vertex set problem in sparse *** kernelization process presented in this paper for the parameterized arc-disjoint triangle packing can be applied to solve the parameterized arc-disjoint triangle packing problem on other restricted directed graph classes.

关键词： tournaments triangle packing kernelization fixed-parameter tractable graph algorithms

Suppression of super-knock in TC-GDI engine using two-stage injection in intake stroke(TSII)

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Science China(Technological Sciences) 2014年第1期57卷 80-85页

作者： wang Zhi XU YaQi wang jianxin State Key Laboratory of Automotive Safety and Energy Tsinghua University

Turbocharging and direct injection are main technologies used for energy-saving gasoline engines. But the biggest challenge is super-knock, whose mechanism is unclear and has no effective strategy to suppress this super-knock until now. The effects of injection strategies on super-knock were experimentally investigated in a turbocharged GDI engine. It was found that two-stage injections during intake stroke （TSII） can eliminate super-knock. Meanwhile, the fuel consumption, emissions and exhaust tem- perature can keep optimized level. By sweeping the start of the 1st injection （SOIl）, end of the 2nd injection （EOI2） and the split injection ratios （ROI2） using 5000 cycles evaluation test at low-speed high load operating point, the optimized injection strategy for the typical TC-GDI engine is TSII with SOIl at middle of intake stroke, EOI2 at end of intake stroke, and ROI2 of 0.3.

关键词： turbocharged GDI engine super-knock injection strategies two-stage injections in intake stroke (TSII)

Effects of Zn, Zn-Al and Zn-P Additions on the Tensile Properties of Sn-Bi Solder

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Acta Metallurgica Sinica(English Letters) 2014年第6期27卷 1159-1164页

作者： Xiaojing wang Yanlai wang Fengjiang wang Ning Liu jianxin wang School of Material and Science Engineering Jiangsu University of Science and Technology Key Laboratory of Semiconductor Photovoltaic Technology of Inner Mongolia Autonomous Region School of Physical Science and Technology Inner Mongolia University

Effects of Zn, Zn-Al and Zn-P additions on melting points, microstructures, tensile properties, and oxidation behaviors of Sn-40 Bi lead-free solder were investigated. The experimental results show that the addition of these three types of elements can refine the microstructures and improve the ultimate tensile strength（UTS） of solder alloys. The fractographic analysis illustrates that ductile fracture is the dominant failure mode in tensile tests of Sn-40Bi-2Zn（SBZ）and Sn-40Bi-2Zn-0.005Al（SBZA） specimens, while brittle fracture is the controlled manner in Sn-40Bi-2Zn-0.005P（SBZP） and Sn-58 Bi solders. XPS analysis indicates that trace amounts of both Al and P additives in solder can improve the antioxidant capacity, whereas only the additive of Al in solder can reduce the thickness of oxidation film.

关键词： Sn-Bi Tensile test Microstructure

Incremental algorithms for the maximum internal spanning tree problem

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Science China(Information Sciences) 2021年第5期64卷 77-84页

作者： Xianbin ZHU Wenjun LI Yongjie YANG jianxin wang School of Computer Science and Engineering Central South University Chair of Economic Theory Saarland University Hunan Provincial Key Laboratory of Intelligent Processing of Big Data on Transportation Changsha University of Science and Technology

The maximum internal spanning tree(MIST) problem is utilized to determine a spanning tree in a graph G,with the maximum number of possible internal *** incremental maximum internal spanning tree(IMIST) problem is the incremental version of MIST whose feasible solutions are edge-sequences e,e,…,esuch that the first k edges form trees for all k ∈ [n-1].A solution’s quality is measured using maxopt(G,k)/|In(T)| with lower being ***,opt(G,k) denotes the number of internal vertices in a tree with k edges in G,which has the largest possible number of internal vertices,and |In(T)| is the number of internal vertices in the tree comprising the solution’s first k *** first obtained an IMIST algorithm with a competitive ratio of 2,followed by a 12/7-competitive algorithm based on an approximation algorithm for MIST.

关键词： maximum internal spanning tree incremental problem approximation algorithm competitive ratio