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Systematic diesel molecular performance evaluation based on quantitative structure-property relationship model

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Petroleum Science 2022年第2期19卷 809-818页

作者： guang-Qing Cai lin-Zhou Zhang State Key Laboratory of Heavy Oil Processing Petroleum Molecular Engineering Center(PMEC)China University of PetroleumBeijing 102249China

The production and separation of optimal molecules in diesel fuels require a systematic property evaluation for the containing *** paper evaluates the diesel molecules based on four key quality indicators:low-temperature fluidity,cleanliness,ignition,and power *** established the corresponding quantitative structure-property relationship models for corresponding properties,which are freezing point,yield sooting index,cetane number,and combustion *** models were applied for the screening of the high-performance molecules that is suitable for *** molecular performance distribution of the conventional diesel and biodiesel were also ***,we analyzed the effect of different transformation paths on molecular properties,giving guidance on the conversion process design.

关键词： Diesel Optimal molecules QSPR Molecular screening

SPECTRAL/HP ELEMENT METHOD WITH HIERARCHICAL RECONSTRUCTION FOR SOLVING NONlinEAR HYPERBOLIC CONSERVATION LAWS

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Acta Mathematica Scientia 2009年第6期29卷 1737-1748页

作者： Zhiliang Xu guang lin Department of Mathematics University of Notre Dame Notre Dame IN 46556 USA Computational Mathematics Group Pacific Northwest National Laboratory 902 Battelle Boulevard Richland WA 99352 USA

The hierarchical reconstruction （HR） [Liu, Shu, Tadmor and Zhang, SINUM ＇07] has been successfully applied to prevent oscillations in solutions computed by finite volume, Runge-Kutta discontinuous Galerkin, spectral volume schemes for solving hyperbolic conservation laws. In this paper, we demonstrate that HR can also be combined with spectral/hp element method for solving hyperbolic conservation laws. An orthogonal spectral basis written in terms of Jacobi polynomials is applied. High computational efficiency is obtained due to such matrix-free algorithm. The formulation is conservative, and essential nomoscillation is enforced by the HR limiter. We show that HR preserves the order of accuracy of the spectral/hp element method for smooth solution problems and generate essentially non-oscillatory solutions profiles for capturing discontinuous solutions without local characteristic decomposition. In addition, we introduce a postprocessing technique to improve HR for limiting high degree numerical solutions.

关键词： spectral/hp element method hierarchical reconstruction discontinuous Galerkin hyperbolic conservation laws

Improved Collaborative Filtering Recommendation Based on Classification and User Trust

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Journal of Electronic Science and Technology 2016年第1期14卷 25-31页

作者： Xiao-lin Xu guang-lin Xu the College of International Vocational Education Shanghai Second Polytechnic University the College of Mathematics and Information Shanghai Lixin University of Commerce

When dealing with the ratings from users,traditional collaborative filtering algorithms do not consider the credibility of rating data,which affects the accuracy of *** address this issue,the paper proposes an improved algorithm based on classification and user *** firstly classifies all the ratings by the categories of *** then,for each category,it evaluates the trustworthy degree of each user on the category and imposes the degree on the ratings of the ***,the algorithm explores the similarities between users,finds the nearest neighbors,and makes recommendations within each *** show that the improved algorithm outperforms the traditional collaborative filtering algorithms and enhances the accuracy of recommendation.

关键词： Collaborative filtering credibility of ratings evaluation on user trust item classification similarity metric

Higher taxa as surrogates of species richness of spiders in insect-resistant transgenic rice

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Insect Science 2012年第3期19卷 419-425页

作者： Sheng lin min-Sheng You Liette Vasseur guang Yang Feng-Jing Liu Feng Guo Institute of Applied Ecology and Research Centre for Biodiversity and Eco-Safety Fujian Agriculture and Forestry University Fuzhou China Department of Biological Sciences Brock University St. Catharines Ontario Canada

Biodiversity assessments can often be time- and resource-consuming. Several alternative approaches have been proposed to reduce sampling efforts, including indicator taxa and surrogates. In this study, we examine the reliability of higher taxon surrogates to predict species richness in two experimental rice fields of Fujian Province, southeastern China during 2005 and 2009. Spider samples in transgenic and nontransgenie plots were collected using a suction sampler. Both the genus and family surrogates had significant and positive linear relationships with species richness in the transgenic and nontransgenic rice fields. The rice varieties did not significantly influence the linear relationships. Our findings suggest that higher-taxon surrogacy could be a useful alternative to complete species inventory for risk assessments of transgenic rice.

关键词： Araneae biodiversity surrogate ecological risk assessment higher-taxonsurrogacy rapid biodiversity assessment taxonomic resolution

Chemical Intervention on Staphylococcus aureus Virulence

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Chinese Journal of Chemistry 2019年第2期37卷 183-193页

作者： lin-lin Zhou Cai-guang Yang State Key Laboratory of Drug Research Shanghai Institute of Materia MedicaChinese Academy of SciencesShanghai 201203China University of the Chinese Academy of Sciences Beijing 100049China

Resistance to conventional antibiotics has raised worldwide attention. Notably, Methicillin-resistant Staphylococcus aureus (MRSA) has become one of the most life-threatening health concerns. Although effective against bacterial infections, conventional antibiotics have also showed a series of side effects such as gut microbiota imbalance.

关键词： Chemical Intervention Staphylococcus aureus Virulence

Optimal mother wavelet-based Lamb wave analyses and damage detection for composite structures

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仪器仪表学报 2007年第10期28卷 1729-1735页

作者： Li Fucai Meng guang Ye lin State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong University Shanghai 200240 China School of Aerospace Mechanical ＆ Mechatronic Engineering The University of Sydney NSW 2006 Australia

With the purpose of on-line structural health monitoring,a transducer network was embedded into compos- ite structure to minimize the influence of *** intrinsic dispersion characteristic of Lamb wave makes the wavelet transform an effective signal processing method for guided *** get high precision in feature extrac- tion,an information entropy-based optimal mother wavelet selection approach was proposed,which was used to choose the most appropriate basis function for particular Lamb wave *** using the embedded sensor network and extracting time-of-flight,delamination in the composite laminate was identified and *** results demon- strate the effectiveness of the proposed methods.

关键词：拉姆波损失探测内传感器信息熵最优小波基

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Tor被动流量分析综述

软件学报 2025年第1期36卷 253-288页

作者：梅汉涛程光朱怡霖周余阳东南大学网络空间安全学院江苏省泛在网络安全工程研究中心(东南大学) 网络空间国际治理研究基地(东南大学) 紫金山实验室

随着网络的蓬勃发展,用户隐私正面临着前所未有的挑战.人们开发出多种匿名通信系统来保护隐私,第2代洋葱路由Tor (the second-generation onion router)是目前最为广泛使用的匿名通信系统.然而,卓越的匿名性也使之成为不法分子犯罪的温... 详细信息

随着网络的蓬勃发展,用户隐私正面临着前所未有的挑战.人们开发出多种匿名通信系统来保护隐私,第2代洋葱路由Tor (the second-generation onion router)是目前最为广泛使用的匿名通信系统.然而,卓越的匿名性也使之成为不法分子犯罪的温床,如今Tor中充斥着非法交易、网络犯罪等. Tor被动流量分析通过被动观察网络流量对Tor进行去匿名化,已成为最热门的去匿名化技术.从Tor与流量分析基本概念出发,介绍Tor被动流量分析技术的应用场景与威胁模型.按照技术类型将现有工作分为流量分类技术与流关联技术,依据分析流程分别对比其流量采集方法、特征提取方法、使用算法.最后探讨当前研究面临的主要挑战与未来可能的研究趋势.

关键词： Tor 流量分析流量分类网站指纹流关联

Porous carbon nanofibers derived from low-softening-point coal pitch towards all-carbon potassium ion hybrid capacitors

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Rare Metals 2022年第11期41卷 3706-3716页

作者： guang-Yuan Wang Xiao-Hong Wang Jin-Feng Sun Ya-min Zhang lin-Rui Hou Chang-Zhou Yuan School of Materials Science and Engineering University of JinanJinan250022China

Potassium ion hybrid capacitors(PIHC)have promising applications in medium and large-scale energy storage systems due to their high energy/power density,abundant potassium resource and low ***,the slow kinetics of battery-type anodes originating from the large-size K+results in a mismatch between the two electrodes,rendering the modest energy density of ***,we first develop an electrospinning strategy to successfully synthesize fibrous precursor by using the HNO_(3)pre-oxidized low-softening-point coal pitch as the low-cost raw *** further carbonization or KOH activation,the two types of carbon nanofibers(CNF)are fabricated as anode and cathode materials,respectively,towards the dual-carbon PIHC *** to its threedimensional interconnected porous conducting network and large layer spacing,the resulted CNF anode material is endowed with high reversible capacities,excellent rate and long cycle ***,the activated CNF cathode with a large surface area of 2169 m^(2)·g^(-1)exhibits excellent capacitive performance.A PIHC constructed with the two fibrous electrodes delivers an energy density of110.0 Wh·kg^(-1)at 200.0 W kg^(-1),along with a capacitance retention of 83.5%after 10,000 cycles at 1.0 A·g^(-1).The contribution here provides a cost-efficiency avenue and platform for advanced dual-carbon PIHC.

关键词： Potassium ion hybrid capacitors(PIHC) Low-softening-point coal pitch Carbon nanofibers(CNF) Dual-carbon devices Long durability

Mode Purity Improvement of High-Order Vortex Waves

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Chinese Journal of Electronics 2022年第6期31卷 1146-1154页

作者： lin Jie YANG guang LI Weiwen AN Cheng Department of Electronic Engineering Xiamen University

Vortex electromagnetic waves can carry orbital angular momentum(OAM) modes of different order number, which are mutually orthogonal. Communication technologies multiplexing different OAM topological charges have attracted extensive attention in improving spectrum utilization. In this regard, the efficient generation of OAM modes becomes a key issue. However, it is difficult to generate high-order OAM modes by using a microstrip antenna with a simple structure, and the mode purity is usually not high. Methodologically, the OAM wave of a microstrip antenna is mostly achieved by synthesizing degenerate eigenmodes. In this paper, combined with eigenmode analysis, the construction of high-order and high-purity OAM mode microstrip antennas is carried out from the perspectives of radiating element,ground plane, and structural symmetry. For a regular hexagonal patch antenna of the 4th-order OAM mode,the mode purity is improved from about 40% to over 80%by removing the inner conductor of the patch layer, using a circular ground plane, and adding lug patches on the outside. This method of improving mode purity through the analysis of mode significance and characteristic current distribution also has guiding significance for the design of other high-order OAM mode patch antennas.

关键词： mode purity improvement regular hexagonal patch antenna vortex electromagnetic waves orbital angular momentum modes microstrip antennas angular momentum antenna radiation patterns microstrip antenna different order number OAM wave current distribution free-space optical communication high-order OAM modes 4th-order OAM mode multiplexing mode significance high-order vortex different OAM topological charges high-order OAM mode patch antennas