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Meaningful String Extraction Based on Clustering for Improving Webpage Classification

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China Communications 2012年第3期9卷 68-77页

作者： Chen Jie tan jianlong Liao Hao Zhou Yanquan Beijing Univ Posts & Telecommun Beijing 100876 Peoples R China Chinese Acad Sci Inst Comp Technol Beijing 100190 Peoples R China Natl Engn Lab Informat Secur Technol Beijing 100190 Peoples R China

Since webpage classification is different from traditional text classification with its irregular words and phrases,massive and unlabeled features,which makes it harder for us to obtain effective *** cope with this problem,we propose two scenarios to extract meaningful strings based on document clustering and term clustering with multi-strategies to optimize a Vector Space Model(VSM) in order to improve webpage *** results show that document clustering work better than term clustering in coping with document ***,a better overall performance is obtained by spectral clustering with document ***,owing to image existing in a same webpage with document content,the proposed method is also applied to extract image meaningful terms,and experiment results also show its effectiveness in improving webpage classification.

关键词： webpage classification meaningfulstring extraction document clustering term cluste-ring k-means spectral clustering

Boosting imbalanced data learning with Wiener process oversampling

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Frontiers of Computer Science 2017年第5期11卷 836-851页

作者： Qian LI Gang LI Wenjia NIU Yanan CAO Liang CHANG jianlong tan Li GUO Institute of Information Engineering Chinese Academy of Sciences Beijing 100093 China School of Information Technology Deakin University Geelong VIC 3125 Australia Guangxi Key Laboratory of Trusted Software Guilin University of Electronic Technology Guilin 541004 China

Learning from imbalanced data is a challenging task in a wide range of applications, which attracts significant research efforts from machine learning and data mining community. As a natural approach to this issue, oversampling balances the training samples through replicating existing samples or synthesizing new samples. In general, synthesization outperforms replication by supplying additional information on the minority class. However, the additional information needs to follow the same normal distribution of the training set, which further constrains the new samples within the predefined range of training set. In this paper, we present the Wiener process oversampling （WPO） technique that brings the physics phenomena into sample synthesization. WPO constructs a robust decision region by expanding the attribute ranges in training set while keeping the same normal distribution. The satisfactory performance of WPO can be achieved with much lower computing complexity. In addition, by integrating WPO with ensemble learning, the WPOBoost algorithm outperforms many prevalent imbalance learning solutions.

关键词： imbalanced-data learning oversampling ensemble learning Wiener process AdaBoost

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杂交鲟“京龙1号”养殖试验

河北渔业 2024年第8期 29-31页

作者：赵强方会卿谭建龙朱静孟秋冬石家庄市水产技术推广站河北石家庄050091 河北省农业农村厅机关服务中心 050061

为对比鲟鱼新品种杂交鲟“京龙1号”和普通西杂鲟(西伯利亚鲟♀×施氏鲟♂杂交)的生长情况,进行了从苗种培育到养殖阶段的养殖对比试验。试验于2023年2月26日放苗,11月23日测产,通过比较两个品种养殖平均体质量、单位产量和成活率,得出... 详细信息

为对比鲟鱼新品种杂交鲟“京龙1号”和普通西杂鲟(西伯利亚鲟♀×施氏鲟♂杂交)的生长情况,进行了从苗种培育到养殖阶段的养殖对比试验。试验于2023年2月26日放苗,11月23日测产,通过比较两个品种养殖平均体质量、单位产量和成活率,得出新品种杂交鲟“京龙1号”具有生长速度快、成活率高、抗病性强、产量高的优点。

关键词：京龙1号西杂鲟养殖

Cesium removal from radioactive wastewater by adsorption and membrane technology

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Frontiers of Environmental Science & Engineering 2024年第3期18卷 161-175页

作者： Shuting Zhuang jianlong Wang School of Environment&Natural Resources Renmin University of ChinaBeijing 100872China Laboratory of Environmental Technology INETTsinghua UniversityBeijing 100084China Beijing Key Laboratory of Radioactive Waste Treatment INETTsinghua UniversityBeijing 100084China

Radiocesium is frequently present in radioactive wastewater,while its removal is still a challenge due to its small hydrated radius,high diffusion coefficient,and similar chemical behavior to other alkali metal elements with high background *** review summarized and analyzed the recent advances in the removal of Cs+from aqueous solutions,with a particular focus on adsorption and membrane separation *** inorganic,organic,and biological adsorbents have undergone assessments to determine their efficacy in the removal of cesium ***,membrane-based separation techniques,including reverse osmosis,forward osmosis,and membrane distillation,have also shown promise in effectively separating cesium ions from radioactive ***,this review summarized the main approaches,including Kurion/SARRY system+desalination system and advanced liquid processing system,implemented after the Fukushima Daiichi nuclear power plant accident in Japan to remove radionuclides from contaminated *** technology and membrane separation technology play a vital role in treatment of contaminated water.

关键词： Cesium Adsorption Membrane separation Advanced liquid processing system Fukushima nuclear accident

Amino acids modified nanoscale zero-valent iron:Density functional theory calculations,experimental synthesis and application in the Fenton-like degradation of organic solvents

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Journal of Environmental Sciences 2024年第1期135卷 296-309页

作者： Xingchen Yang Fucheng Ming jianlong Wang Lejin Xu Department of Nuclear Engineering and Technology School of Energy and Power EngineeringHuazhong University of Science and TechnologyWuhan 430074China China-EU Institute for Clean and Renewable Energy Huazhong University of Science and TechnologyWuhan 430074China Institute of Nuclear and New Energy Technology Key Laboratory of Advanced Reactor Engineering and Safety of Ministry of EducationTsinghua UniversityBeijing 100084China Beijing Key Laboratory of Radioactive Wastes Treatment Tsinghua UniversityBeijing 100084China

To improve the adsorption and catalytic performance of heterogeneous Fenton-like catalysts for oil wastes,amino acids were used to modify nanoscale zero-valent iron(AA@Fe^(0)),which were applied in the Fenton-like degradation of organic solvents(tributyl phosphate and n-dodecane,named TBP and DD).Twelve amino acids,i.e.,glycine(Gly),alanine(Ala),leucine(Leu),proline(Pro),phenylalanine(Phe),methionine(Met),cysteine(Cys),asparagine(Asn),serine(Ser),glutamic acid(Glu),lysine(Lys)and arginine(Arg),were selected and calculated by density functional theory(DFT).The optimized structure,charge distribution,the highest occupied molecular orbital(HOMO),the lowest unoccupied molecular orbital(LUMO),interaction region indicator(IRI)isosurface map and adsorption energy of AA@Fe^(0),AA@Fe^(0)-TBP and AA@Fe^(0)-DD were studied,which indicated that Fe is more likely to approach and charge transfer with-COO and-NH_(3) on theα-carbon of amino *** is strong attraction between Fe and–COO,and Van der Waals force between Fe and-NH_(3),*** the interaction of AA@Fe^(0)with TBP and DD,Van der Waal force plays an important ***@Fe^(0)was synthesized in laboratory and characterized to investigate physicochemical *** Fenton-like degradation of organic solvents,the change of COD in water phase during the degradation process as well as the volume of the organic phase after the reaction were *** results of calculations combined with experiments showed that Ser-modified Fe^(0)performed the best in these amino acids,with 98%removal of organic solvents.A possible catalytic mechanism was proposed in which amino acids acted a linking role between Fe and organic solvents,activating H_(2)O_(2)to generate hydroxyl radicals for the degradation of organic solvents.

关键词： Amino acids Nanoscale zero-valent iron Density functional theory Organic solvents Fenton-like degradation

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基于本体的权限管理系统的研究与实现

计算机工程 2005年第13期31卷 43-45页

作者：李栋栋谭建龙中国科学院计算技术研究所软件室

设计实现了一个基于本体的权限管理系统,该系统使用本体对业务层面上与操作相关的信息进行概念建模,实现了一个对具有业务内涵的、范围相当广泛的一类广义操作进行权限定义、管理的合适的表达框架和管理机制。同时,该系统是独立于应用的... 详细信息

设计实现了一个基于本体的权限管理系统,该系统使用本体对业务层面上与操作相关的信息进行概念建模,实现了一个对具有业务内涵的、范围相当广泛的一类广义操作进行权限定义、管理的合适的表达框架和管理机制。同时,该系统是独立于应用的,可以为多种应用程序提供统一的权限管理支持。

关键词：权限管理授权访问控制本体拦截器

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基于包内容的未知蠕虫发现

计算机工程 2006年第8期32卷 178-180页

作者：张吉谭建龙郭莉中国科学院计算技术研究所软件室

根据蠕虫抽象共性,提出了一种基于包内容的未知蠕虫发现策略,并实现了对应的原型系统。在具体实现中,解决了数据包中重复串快速统计和增量维护多串匹配的问题,并比较了系统参数对其性能的影响。模拟实验的结果表明:该系统具有较高的发... 详细信息

根据蠕虫抽象共性,提出了一种基于包内容的未知蠕虫发现策略,并实现了对应的原型系统。在具体实现中,解决了数据包中重复串快速统计和增量维护多串匹配的问题,并比较了系统参数对其性能的影响。模拟实验的结果表明:该系统具有较高的发现率和较低的误报率,处理性能达到40Mbps,可多台并行部署于骨干网结点处进行蠕虫检测。

关键词：未知蠕虫包内容串匹配网络安全

Mass transfer enhancement and hydrodynamic performance with wire mesh coupling solid particles in bubble column reactor

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Chinese Journal of Chemical Engineering 2024年第3期67卷 195-205页

作者： Chuanjun Di Jipeng Dong Fei Gao Guanghui Chen Pan Zhang jianlong Li Key Laboratory of Multiphase Flow Reaction and Separation Engineering of Shandong Province College of Chemical EngineeringQingdao University of Science and TechnologyQingdao 266042China College of Electromechanical Engineering Qingdao University of Science and TechnologyQingdao 266043China

It is of vital significance to investigate mass transfer enhancements for chemical engineering *** work focuses on investigating the coupling influence of embedding wire mesh and adding solid particles on bubble motion and gas-liquid mass transfer process in a bubble *** image velocimetry(PIV)technology was employed to analyze the flow field and bubble motion behavior,and dynamic oxygen absorption technology was used to measure the gas-liquid volumetric mass transfer coefficient(kLa).The effect of embedding wire mesh,adding solid particles,and wire mesh coupling solid particles on the flow characteristic and kLa were analyzed and *** results show that the gas-liquid interface area increases by 33%-72%when using the wire mesh coupling solid particles strategy compared to the gas-liquid two-phase flow,which is superior to the other two strengthening *** with the system without reinforcement,kLa in the bubble column increased by 0.5-1.8 times with wire mesh coupling solid particles method,which is higher than the sum of kLa increases with inserting wire mesh and adding particles,and the coupling reinforcement mechanism for affecting gas-liquid mass transfer process was discussed to provide a new idea for enhancing gas-liquid mass transfer.

关键词： Fluid mechanics Bubble Mass transfer Wire mesh coupling solid particles Particle image velocimetry Hydrodynamics

Solubility determination and comparison ofβ-HMX and RDX in two binary mixed solvents(acetonitrile+water,nitric acid+water)

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Chinese Journal of Chemical Engineering 2024年第5期69卷 238-249页

作者： Yuehua Yao Fan Wang Yinguang Xu Zishuai Xu Lizhen Chen jianlong Wang School of Chemistry and Chemical Engineering North University of ChinaTaiyuan 030051China Gansu Yinguang Chemical Industry Group Co.Ltd. Baiyin 730900China

In order to remove hexahydro-1,3,5-trinitro-1,3,5-triazine(RDX),the main impurity,in process of polymorphic transformation of octrahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine(HMX),the solubility ofβ-HMX and RDX in acetonitrile(ACN)+water in the temperature range of 288.15-333.15 K and in nitric acid(HNO_(3))+water in the temperature range of 298.15-333.15 K were measured by laser dynamic *** results showed that the solubility of bothβ-HMX and RDX in binary mixed solvents increased monotonously as the temperature increase at a given solvent composition or with increasing of mole fraction of solvent(ACN and nitric acid).Solubility data were well correlated by the modified Apelblat equation,Jouyban-Acree model,Yaws equation and van't Hoff equation,and the Yaws equation achieved the best fitting results according to the relative error and the mean square error ***,the solubility ofβ-HMX and RDX in binary mixed solvent was compared,based on the solubility difference and the solvent's own properties,the best separation degree ofβ-HMX and RDX was found when the mole fraction of nitric acid was 0.22 at room temperature,which provided data support for HMX crystallization in mixed *** solubility differences between RDX andβ-HMX in mixed solvents were explained from the formation of intermolecular and intramolecular hydrogen bonds.

关键词： Solubility Octrahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine Hexahydro-1,3,5-trinitro-1,3,5-triazine Separation Model Hydrogen bond