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Optimizing Multi-Dimensional Packet Classification for Multi-Core Systems

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Journal of Computer Science & Technology 2018年第5期33卷 1056-1071页

作者： Tong Shen Da-Fang zhang Gao-Gang Xie xin-yi zhang College of Computer Science and Electronic Engineering Hunan University Changsha 410082 China Network Technology Research Center Institute of Computing Technology Chinese Academy of Sciences Beijing 100190 China State Key Laboratory of Computer Architecture Institute of Computing Technology Chinese Academy of Sciences Beijing 100190 China University of Chinese Academy of Sciences Beijing 100049 China

Packet classification has been studied for decades; it classifies packets into specific flows based on a given rule set. As software-defined network was proposed, a recent trend of packet classification is to scale the five-tuple model to multi-tuple. In general, packet classification on multiple fields is a complex problem. Although most existing software-based algorithms have been proved extraordinary in practice, they are only suitable for the classic five-tuple model and difficult to be scaled up. Meanwhile, hardware-specific solutions are inflexible and expensive, and some of them are power consuming. In this paper, we propose a universal multi-dimensional packet classification approach for multi-core systems. In our approach, novel data structures and four decomposition-based algorithms are designed to optimize the classification and updating of rules. For multi-field rules, a rule set is cut into several parts according to the number of fields. Each part works independently. In this way, the fields are searched in parallel and all the partial results are merged together at last. To demonstrate the feasibility of our approach, we implement a prototype and evaluate its throughput and latency. Experimental results show that our approach achieves a 40% higher throughput than that of other decomposed-based algorithms and a 43% lower latency of rule incremental update than that of the other algorithms on average. Furthermore, our approach saves 39% memory consumption on average and has a good scalability.

关键词： multi-dimensional multi-core packet classification

Value of magnetic resonance diffusion combined with perfusion imaging techniques for diagnosing potentially malignant breast lesions

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World Journal of Clinical Cases 2022年第18期10卷 6021-6031页

作者： Hui zhang xin-yi zhang Yong Wang Department of Radiology Hebei General HospitalShijiazhuang 050000Hebei ProvinceChina Department of Radiology the First Hospital of Hebei Medical UniversityShijiazhuang 050000Hebei ProvinceChina

BACKGROUND Lesions of breast imaging reporting and data system(BI-RADS)4 at mammography vary from benign to malignant,leading to difficulties for clinicians to distinguish between *** specificity of magnetic resonance imaging(MRI)in detecting breast is relatively low,leading to many false-positive results and high rates of re-examination or ***-weighted imaging(DWI),combined with perfusion-weighted imaging(PWI),might help to distinguish between benign and malignant BI-RADS 4 breast lesions at *** To evaluate the value of DWI and PWI in diagnosing BI-RADS 4 breast *** This is a retrospective study which included patients who underwent breast MRI between May 2017 and May 2019 in the *** lesions were divided into benign and malignant groups according to the classification of histopathological *** diagnostic efficacy of DWI and PWI were analyzed respectively and *** 95 lesions were divided according to histopathological diagnosis,with 46 benign and 49 *** main statistical methods used included the Student t-test,the Mann-Whitney U-test,the chi-square test or Fisher’s exact *** The mean apparent diffusion coefficient(ADC)values in the parenchyma and lesion area of the normal mammary gland were 1.82±0.22×10^(-3)mm^(2)/s and 1.24±0.16×10^(-3)mm^(2)/s,respectively(P=0.021).The mean ADC value of the malignant group was 1.09±0.23×10^(-3)mm^(2)/s,which was lower than that of the benign group(1.42±0.68×10^(-3)mm^(2)/s)(P=0.016).The volume transfer constant(Ktrans)and rate constant(Kep)values were higher in malignant lesions than in benign ones(all P<0.001),but there were no significant statistical differences regarding volume fraction(V_(e))(P=0.866).The sensitivity and specificity of PWI combined with DWI(91.7%and 89.3%,respectively)were higher than that of PWI or DWI *** accuracy of PWI combined with DWI in predicting pathological results was significantly higher than that predicted

关键词： Magnetic resonance imaging Breast diseases Diffusion-weighted imaging Perfusion-weighted imaging

Suppressing oxygen redox in layered oxide cathode of sodium-ion batteries with ribbon superstructure and solid-solution behavior

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Journal of Materials Science & Technology 2023年第29期160卷 9-17页

作者： Zhi-Xiong Huang Xue-Li zhang xin-xin Zhao Hong-Yan Lü xin-yi zhang Yong-Li Heng Hongbo Geng xing-Long Wu MOE Key Laboratory for UV Light-Emitting Materials and Technology Northeast Normal UniversityChangchunJilin 130024China School of Materials Engineering Changshu Institute of TechnologyChangshuJiangsu 215500China Faculty of Chemistry Northeast Normal UniversityChangchunJilin 130024China

Sodium-ion batteries(SIBs)are proved as one of the most acceptable candidates for replacing lithium-ion batteries in some fields by virtue of a similar“rocking chair”mechanism and the abundance of *** voltage,rate performance,and energy density of these batteries are mainly determined by the ***,a Li-Ni-Co co-substituted P2-Na_(0.67)[Li_(0.1)(Mn_(0.7)Ni_(0.2)Co_(0.1))_(0.9)]O_(2)(NLMNC)with ribbon super-structure is prepared with the aim of multi-ion synergistic *** to the addition of Ni and Co,the Jahn-Teller distortion of Mn can be suppressed corresponding with the improved structural stability,and a little bit of oxygen redox activities is *** with the substitution of 10%Li,the X-ray diffraction(XRD)peaks of NLMNC show the ribbon superstructure at about 21°and 22°.The smooth charge/discharge profiles of the NLMNC cathode exhibit the solid-solution *** addition,the platform at high voltage disappears corresponding with the existing oxygen redox activities being suppressed which may be related to the ribbon superstructure and the promotion of the Ni *** NLMNC cathode can deliver a reversible discharge capacity of 123.5 mA h g^(-1)at 10 mA g^(-1).Even if the current density increases to 500 mA g^(-1),a reversible discharge capacity of 112.8 mA h g^(-1)still can be *** distinguished cycling stability is related to the reversible migration of Li+between the metal oxide layer and the interlayer and low volume change during *** is also needing to be mentioned that the capacity retention of NLMNC cathode is about 94.4%(based on the highest discharge capacity)after 100 *** work presents an effective route to develop high-performance cathodes for SIBs.

关键词： Sodium-ion batteries Layered oxides Ribbon superstructure Solid-solution reaction

The Aviation Technology Two-Sided Matching with the Expected Time Based on the Probabilistic Linguistic Preference Relations

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Journal of the Operations Research Society of China 2020年第1期8卷 45-77页

作者： Bo Li yi-xin zhang Ze-Shui Xu Institute for Disaster Management and Reconstruction Sichuan UniversityChengdu 610207China Business School State Key Laboratory of Hydraulics and Mountain River EngineeringSichuan UniversityChengdu 610064China School of Computer Science University of ManchesterManchester M139PLUnited Kingdom

The two-sided matching has been widely applied to the decision-making problems in the field of *** the limited working experience,the two-sided agents usually cannot provide the preference order directly for the opposite agent,but rather to provide the preference relations in the form of linguistic *** preference relations based on probabilistic linguistic term sets(PLTSs)not only allowagents to provide the evaluation with multiple linguistic terms,but also present the different preference degrees for linguistic *** the diversities of the agents,they may provide their preference relations in the form of the probabilistic linguistic preference relation(PLPR)or the probabilistic linguistic multiplicative preference relation(PLMPR).For two-sided matching with the expected time,we first provide the concept of the time satisfaction degree(TSD).Then,we transform the preference relations in different forms into the unified preference relations(u-PRs).The consistency index to measure the consistency of u-PRs is ***,the acceptable consistent u-PRs are constructed,and an algorithm is proposed to modify the unacceptable consistent ***,we present the whole two-sided matching decisionmaking process with the acceptable consistent ***,a case about aviation technology suppliers and demanders matching is presented to exhibit the rationality and practicality of the proposed *** analyses and discussions are provided to further demonstrate the feasibility and effectiveness of the proposed method.

关键词： Two-sided matching Time satisfaction degree Probabilistic linguistic term sets Preference relation Aviation technology

Discrimination of Pb-Zn deposit types using sphalerite geochemistry: New insights from machine learning algorithm

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Geoscience Frontiers 2023年第4期14卷 200-219页

作者： Xiao-Ming Li yi-xin zhang Zhan-Ke Li xin-Fu Zhao Ren-Guang Zuo Fan Xiao yi Zheng School of Earth Resources China University of GeosciencesWuhanHubei Province 430074China School of Computer Science China University of GeosciencesWuhanHubei Province 430078China State Key Laboratory of Geological Processes and Mineral Resources China University of GeosciencesWuhan 430074China School of Earth Sciences and Engineering Sun Yat-Sen UniversityZhuhaiGuangdong Province 519000China

Due to the combined influences such as ore-forming temperature,fluid and metal sources,sphalerite tends to incorporate diverse contents of trace elements during the formation of different types of Lead-zinc(Pb-Zn)***,trace elements in sphalerite have long been utilized to distinguish Pb-Zn deposit ***,previous discriminant diagrams usually contain two or three dimensions,which are limited to revealing the complicated interrelations between trace elements of sphalerite and the types of Pb-Zn *** this study,we aim to prove that the sphalerite trace elements can be used to classify the Pb-Zn deposit types and extract key factors from sphalerite trace elements that can dis-criminate Pb-Zn deposit types using machine learning algorithms.A dataset of nearly 3600 sphalerite spot analyses from 95 Pb-Zn deposits worldwide determined by LA-ICP-MS was compiled from peer-reviewed publications,containing 12 elements(Mn,Fe,Co,Cu,Ga,Ge,Ag,Cd,In,Sn,Sb,and Pb)from 5 types,including Sedimentary Exhalative(SEDEX),Mississippi Valley Type(MVT),Volcanic Massive Sulfide(VMS),skarn,and epithermal *** Forests(RF)is applied to the data processing and the results show that trace elements of sphalerite can successfully discriminate different types of Pb-Zn deposits except for VMS deposits,most of which are falsely distinguished as skarn and epithermal *** further discriminate VMS deposits,future studies could focus on enlarging the capacity of VMS deposits in datasets and applying other geological factors along with sphalerite trace elements when con-structing the classification ***’s feature importance and permutation feature importance were adopted to evaluate the element significance for ***,a visualized tool,t-distributed stochastic neighbor embedding(t-SNE),was used to verify the results of both classification and *** results presented here show that Mn,Co,and Ge display significant impacts on classifica

关键词： Discrimination Pb-Zn deposit Sphalerite trace elements Machine learning algorithms Feature analysis

Influence of Backbone and Axial Substituent of Catalyst onα-Imino-ketone Nickel Mediated Ethylene(Co)Polymerization

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Chinese Journal of Polymer Science 2022年第5期40卷 469-477页

作者： Yu-Kai Chu Xiao-Qiang Hu Yue zhang Da-Jun Liu yi-xin zhang Zhong-Bao Jian College of Chemistry and Environmental Engineering Changchun University of Science and TechnologyChangchun 130022China State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 730022China

Theα-imino-ketone nickel catalyst is an emerging versatile platform that is easy to prepare and allows for the production of branched high molecular weight functionalized ***,study on this catalyst system is rare thus *** this contribution,by introducing different backbones,flexible and rigid axial substituents into theα-imino-ketone framework,a family of cationic nickel catalysts were synthesized and fully *** the addition of any activator,systematic studies on ethylene polymerization and copolymerization with polar monomers were performed to explore the influence of both backbone and axial substituent on catalytic activity,polymer molecular weight,branching density and *** particular,owing to the unique semi-opening feature of theα-imino-ketone framework,the preferred nickel catalyst exhibited high activity of 175 kg·mol^(-1)·h^(-1)to produce functionalized polyethylene with molecular weight of 13.4 kg·mol^(-1)and comonomer incorporation of 2.9 mol%.

关键词： Olefin polymerization α-Imino-ketone ligand Nickel catalyst Polar monomer

APPLICATION OF TWO-DIMENSIONAL WAVELET TRANSFORM IN NEAR-SHORE X-BAND RADAR IMAGES

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Journal of Hydrodynamics 2011年第2期23卷 179-186页

作者： FENG Xiang-bo YAN yi-xin, zhang Wei State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering and College of Harbor Coastal and Offshore Engineering Hohai University Nanjing 210098 China

Among existing remote sensing applications, land-based X-band radar is an effective technique to monitor the wave fields, and spatial wave information could be obtained from the radar images. Two-dimensional Fourier Transform （2-D FT） is the common algorithm to derive the spectra of radar images. However, the wave field in the nearshore area is highly non-homogeneous due to wave refraction, shoaling, and other coastal mechanisms. When applied in nearshore radar images, 2-D FT would lead to ambiguity of wave characteristics in wave number domain. In this article, we introduce two-dimensional Wavelet Transform （2-D WT） to capture the non-homogeneity of wave fields from nearshore radar images. The results show that wave number spectra by 2-D WT at six parallel space locations in the given image clearly present the shoaling of nearshore waves. Wave number of the peak wave energy is increasing along the inshore direction, and dominant direction of the spectra changes from South South West （SSW） to West South West （WSW）. To verify the results of 2-D WT, wave shoaling in radar images is calculated based on dispersion relation. The theoretical calculation results agree with the results of 2-D WT on the whole. The encouraging performance of 2-D WT indicates its strong capability of revealing the non-homogeneity of wave fields in nearshore X-band radar images.

关键词： non-homogeneity X-band radar two-dimensional Wavelet Transform (2-D WT) dispersion relation nearshore wave field

Where is the future of China's biogas? Review, forecast,and policy implications

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Petroleum Science 2016年第3期13卷 604-624页

作者： Lei Gu yi-xin zhang Jian-Zhou Wang Gina Chen Hugh Battye College of Earth and Environmental Sciences Lanzhou University School of Mathematics and Statistics Lanzhou University School of Statistics Dongbei University of Finance and Economics School of Law Northwestern University School of History and Culture Lanzhou University Department of Economics The London School of Economics and Political Science

This paper discusses the history and present status of different categories of biogas production in China,most of which are classified into rural household production,agriculture-based engineering production,and industry-based engineering *** evaluate the future biogas production of China,five models including the Hubbert model,the Weibull model,the generalized Weng model,the H-C-Z model,and the Grey model are applied to analyze and forecast the biogas production of each province and the entire *** is proved that those models which originated from oil research can also be applied to other energy *** simulation results reveal that China＇s total biogas production is unlikely to keep on a fast-growing trend in the next few years,mainly due to a recent decrease in rural household production,and this greatly differs from the previous goal set by the official *** addition,China＇s biogas production will present a more uneven pattern among regions in the *** paper will give preliminary explanation for the regional difference of the three biogas sectors and propose some recommendations for instituting corresponding policies and strategies to promote the development of the biogas industry in China.

关键词： Biogas production China Temporal–spatial Forecast Policy

Benzodiazepines in complex biological matrices: Recent updates on pretreatment and detection methods

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Journal of Pharmaceutical Analysis 2023年第5期13卷 442-462页

作者： yi-xin zhang Yuan zhang Yu Bian Ya-jie Liu Ai Ren Yu Zhou Du Shi Xue-Song Feng School of Pharmacy China Medical UniversityShenyang110122China Department of Pharmacy National Cancer Center/National Clinical Research Centerfor Cancer/Cancer Hospital ChineseAcademy of Medical Sciences and Peking Union Medical CollegeBeijing100021China Department of Urology The First Hospital of China Medical UniversityShenyang110001China

Benzodiazepines(BDZs)are used in clinics for anxiolysis,anticonvulsants,sedative hypnosis,and muscle *** have high consumptions worldwide because of their easy availability and potential *** are often used for suicide or criminal practices such as abduction and drug-facilitated sexual *** pharmacological effects of using small doses of BDZs and their detections from complex biological matrices are *** pretreatment methods followed by accurate and sensitive detections are ***,pretreatment methods for the extraction,enrichment,and preconcentration of BDZs as well as the strategies for their screening,identification,and quantitation developed in the past five years have been ***,recent advances in various methods are *** and advantages of each method are *** directions of the pretreatment and detection methods for BDZs are also reviewed.

关键词： Benzodiazepine Biological matrices Detectionmethods Samplepreparation