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Tunable-Q contourlet transform for image representation

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Journal of Systems Engineering and Electronics 2013年第1期24卷 147-156页

作者： haijiang wang Qinke Yang Rui Li Zhihong Yao Institute of Soil and Water Conservation Chinese Academy of Sciences and Ministry of Water Resources College of Urban and Environment Science Shanxi Normal University College of Urban and Environmental Sciences Northwest University College of Resources and Environment North China University of Water Resources and Electric Power

A novel tunable-quality-factor （tunable-Q） contourlet transform for geometric image representation is proposed. The Laplacian pyramid in original contourlet decomposes a signal into channels that have the same bandwidth on a logarithmic scale, and is not suitable for images with different behavior in frequency domain. We employ a new tunable-Q decomposition defined in the frequency domain by which one can flexibly tune the bandwidth of decomposition channels. With an acceptable redundancy, this tunable-Q contourlet is also anti-aliasing and its basis is sharply localized in the desired area of frequency and spatial domain. Our experiments in nonlinear approximation and denoising show that the contourlet using a better-suitable quality factor can achieve a more promising performance and often outperform wavelets and the previous contourlets both in visual quality and in terms of peak signal-to-noise ratio.

关键词： contourlet quality factor (Q-factor) anti-aliasing mul-tiscale decomposition.

A model study of the equation of state,quark-number susceptibility and scalar susceptibility of QCD at finite chemical potential and zero temperature

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Science China(Physics,Mechanics & Astronomy) 2012年第12期55卷 2425-2433页

作者： ZHU HuiXia wang haijiang PAN DanFeng ZONG HongShi Department of Physics Nanjing UniversityNanjing 210093China The College of Physics and Electronic Information Anhui Normal UniversityWuhu 241000China Joint Center for Particle Nuclear Physics and CosmologyNanjing 210093China

In this article,we try to calculate the equation of state(EOS) of quantum chromodynamics(QCD) at finite chemical potential and zero temperature in the framework of a nonperturbative QCD *** with the cold,perturbative EOS of QCD proposed by Fraga et al.,our EOS approaches more fastly to the free quark gas result at large chemical *** is expected that our EOS can provide a possible new tool for the study of neutron *** also try to provide a direct approach for calculating quark number susceptibility and scalar susceptibility at finite chemical potential and zero temperature.

关键词： the equation of state quark number density quark-number susceptibility scalar susceptibility phase transition

Performance improvement for air-cooled open-cathode proton exchange membrane fuel cell with different design parameters of the gas diffusion layer

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Progress in Natural Science:Materials International 2020年第6期30卷 825-831页

作者： Chen Zhao Shuang Xing Wei Liu Ming Chen haijiang wang Department of Mechanical and Energy Engineering Southern University of Science and Technology

Air-cooled open-cathode LTPEMFC(AO-LTPEMFC) has been developed as a new power source for the portable power supply. The effect of the gas diffusion layer(GDL) on AO-LTPEMFC operation in challenging ambient air conditions was investigated in the present study. The effect of the content of polytetrafluoroethylene(PTFE) on the substrate layer and microporous layer(MPL), the thickness of GDL and the pulse width modulation(PWM) of the fan on cell performance as well as the cathode outlet surface temperature distribution were investigated. The polarization curves, electrochemical impedance spectroscopy(EIS) and dynamic voltage test were used to correlate the structural characteristics of GDL with heat dissipation, oxygen transport and water management in AO-LTPEMFC. The results showed that GDL with appropriate PTFE content in the substrate layer and MPL could significantly optimize cell performance. In addition, the thickness of GDL also had a certain impact on the mass and heat transfer of the fuel cell, while the water management in GDL was affected by PWM of the fan, simultaneously. Combined with the practice process, the optimum values of the substrate layer PTFE content, MPL layer PTFE content and thickness of GDL were identified to be 10%, 40%, and 200 μm, respectively.

关键词： Gas diffusion layer (GDL) MPL Substrate layer PTFE content Thickness Air-cooled open cathode LT- PEMFC

Numerical Green’s function method:Application to quantifying ground motion variations of M7 earthquakes

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Earthquake Science 2010年第3期23卷 205-214页

作者： haijiang wang Heiner Igel Frantisek Gallovic School of Earth and Space Sciences University of Science and Technology of China Hefei 230026 China Department of Earth and Environmental Studies Section Geophysics Ludwig-Maximilians-University Miinchen 80333 Germany Mengcheng National Geophysical Observatory School of Earth and Space Sciences University of Science and Technology of China Mengcheng 233527 China

The concept of ＂numerical Green’s functions＂（NGF or Green’s function database） is developed. The basic idea is： a large seismic fault is divided into subfaults of appropriate size, for which synthetic Green’s functions at the surface （NGF） are calculated and stored. Consequently, ground motions from arbitrary kinematic sources can be simulated, rapidly, for the whole fault or parts of it by superposition. The target fault is a simplified, vertical model of the Newport-Inglewood fault in the Los Angeles basin. This approach and its functionality are illustrated by investigating the variations of ground motions （e.g. peak ground velocity and synthetic seismograms） due to the source complexity. The source complexities are considered with two respects： hypocenter location and slip history. The results show a complex behavior, with dependence of absolute peak ground velocity and their variation on source process directionality, hypocenter location, local structure, and static slip asperity location. We concluded that combining effect due to 3-D structure and finite-source is necessary to quan- tify ground motion characteristics and their variations. Our results will facilitate the earthquake hazard assessment projects.

关键词： numerical Green's function ground motion variation hypocenter location static displacement distribution

Secure key-aggregation authorized searchable encryption

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Science China(Information Sciences) 2019年第3期62卷 220-222页

作者： haijiang wang Xiaolei DONG Zhenfu CAO Dongmei LI Nanyuan CAO School of Information and Electronic Engineering Zhejiang University of Science and Technology Department of Computer Science and Engineering Shanghai Jiao Tong University Shanghai Key Lab for Trustworthy Computing East China Normal University

Dear editor,Selective sharing of encrypted documents with other users makes the cloud storage system more flexible and effective [1]. For safety reasons, data owners use different keys to encrypt different documents. ... 详细信息

关键词： MSK ID length

3D-printed fuel-cell bipolar plates for evaluating flow-field performance

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Clean Energy 2020年第2期4卷 142-157页

作者： Hossein Piri Xiaotao T.Bi Hui Li haijiang wang Clean Energy Research Centre&Department of Chemical and Biological Engineering The University of British ColumbiaCanada Southern University of Science and Technology of China ShenzhenChina

In the last decade,many researchers have focused on developing fuel-cell flow-field designs that homogeneously distribute reactants with an optimum pressure *** of the previous studies are numerical simulations and the few experimental studies conducted have used very simple flow-field geometries due to the limitations of the conventional fabrication techniques.3D printing is an excellent rapid prototyping method for prototyping bipolar plates(BPPs)to perform experiments on new flow-field *** present research investigates the applicability of different 3D-printed BPPs for studying fluid-dynamic ***-of-the-art flow-field designs are fabricated using PolyJet 3D printing,stereolithographic apparatus(SLA)3D printing and laser-cutter technologies,and the pressure-drop and velocity profiles are measured for each *** results demonstrate that SLA BPPs have great promise in serving as a screening tool in modifying flow-field design with a small feature size.

关键词： PEM fuel cell bipolar plate prototyping 3D printing pressure drop velocity profile

An Approach towards Synthesis of Nanoarchitectured LiNi1/3Co1/3Mn1/3O2 Cathode Material for Lithium Ion Batteries

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Chinese Journal of Chemistry 2015年第2期33卷 261-267页

作者： Weibo Hua Yanjie wang Yanjun Zhong Guoping wang Benhe Zhong Baizeng Fang Xiaodong Guo Shixuan Liao haijiang wang College of Chemical Engineering Sichuan UniversityChengduSichuan 610065China Department of Chemical and Biological Engineering University of British Columbia2360 East MallVancouverBCCanadaV6T 1Z3 Institute for Fuel Cell Innovation National Research Council of Canada4250 Wesbrook MallVancouverBC V6T 1W5Canada College of Chemical Engineering University of South ChinaHengyangHunan 421001China

To explore advanced cathode materials for lithium ion batteries(LIBs),a nanoarchitectured LiNi_(1/3)Co_(1/3)Mn_(1/3)O_(2)(LNCM)material is developed using a modified carbonate coprecipitation method in combination with a vacuum distillation-crystallisation *** with the LNCM materials produced by a traditional carbonate copre-cipitation method,the prepared LNCM material synthesized through this modified method reveals a better hexago-nal layered structure,smaller particle sizes(ca.110.5 nm),and higher specific surface *** of its unique structural characteristics,the as-prepared LNCM material demonstrates excellent electrochemical properties in-cluding high rate capability and good cycleability when it is utilized as a cathode in the lithium ion battery(LIB).

关键词： cathode materials nanoarchitectured coprecipitation electrochemical properties lithium ion battery

Self-adaptive resource allocation for cloud-based software services based on progressive QoS prediction model

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Science China(Information Sciences) 2019年第11期62卷 192-194页

作者： Xing CHEN Junxin LIN Yun MA Bing LIN haijiang wang Gang HUANG College of Mathematics and Computer Science Fuzhou University Fujian Key Laboratory of Network Computing and Intelligent Information Processing Fuzhou University School of Software Tsinghua University College of Physics and Energy Fujian Normal University Key Laboratory of High Confidence Software Technologies Ministry of Education

Dear editor,Self-adaptation is a promising approach to allocate resources for cloud-based software services [1, 2].Traditional self-adaptive resource-allocation methods are rule-driven, which leads to high administrat... 详细信息

关键词： service Self-adaptive resource allocation for cloud-based software services based on progressive QoS prediction model

Origin of Crude Oil in the Lunnan Region,Tarim Basin

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Acta Geologica Sinica(English Edition) 2010年第5期84卷 1157-1169页

作者： LI Sumei PANG Xiongqi YANG Haijun XIAO Zhongyao GU Qiaoyuan ZHANG Baoshou wang haijiang State Key Laboratory of Petroleum Resource and Prospecting China University of Petroleum Beijing 102249 China PetroChina Tarim Oilfield Company Kuerle 841000 Xinjiang China

The oil source of the Tarim Basin has been controversial over a long time. This study characterizes the crude oil and investigates the oil sources in the Lunnan region, Tarim Basin by adopting compound specific isotopes of n-alkanes and biomarkers approaches. Although the crude oil has a good correlation with the Middle-Upper Ordovician （02＋3） source rocks and a poor correlation with the Cambrian-Lower Ordovician （C-O1） based on biomarkers, the ~3C data of n-alkanes of the Lunnan oils show an intermediate value between C-O1 and 02＋3 genetic affinity oils, which suggests that the Lunnan oils are actually of an extensively mixed source. A quantification of oil mixing was performed and the results show that the contribution of the Cambrian-Lower Ordovician source rocks ranges from 11% to 70% （averaging 36%）, slightly less than that of the Tazhong uplift. It is suggested that the inconsistency between the biomarkers and od3C in determining the oil sources in the Lunnan Region results from multiple petroleum charge episodes with different chemical components in one or more episode（s） and different sources. The widespread marine mixed-source oil in the basin indicates that significant petroleum potential in deep horizons is possible. To unravel hydrocarbons accumulation mechanisms for the Lunnan oils is crucial to further petroleum exploration and exploitation in the region.

关键词： Lunnan uplift biomarkers compound specific isotopes oilsource rock correlation mixed-source oil