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Atmospheric and kinetic studies of OH and HO_2 by the FAGE technique

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Journal of Environmental Sciences 2012年第1期24卷 78-86页

作者： D.Amedro k.Miyazaki A.Parker c.Schoemaecker c.Fittschen Laboratoire Pc2A Universit de Lille 1- Ba timent C1159655 Villeneuve d'AscqFrance Department of Applied chemistry Tokyo Metropolitan UniversityJapan

A new FAGE setup has recently been built at the University of Lille,*** permits the quantification of OH and HO 2 in the atmosphere with a detection limit of 3×10 5 molecules/（cm 3 ·min） for OH and 1×10 6 molecules/（cm 3 ·min） for HO *** coupling to a photolysis cell enables the measurement of the total reactivity of the hydroxyl radical in ambient air and kinetic studies in *** configurations have been considered：one with the photolysis cell at 90° to the FAGE nozzle,the other on line with the FAGE *** two configurations have been tested and validated by measuring the well known rate constants of OH with cH 4,c 3 H 8 and *** advantages and drawbacks of each configuration have been *** ＂on line＂ configuration limits losses and permits measurements over a larger reactivity range but is affected by OH formation from the laser beam striking the FAGE nozzle,thus limiting the ability to carry out energy dependence studies which can,in contrast,be successfully performed in the 90° configuration.

关键词： OH kinetic reactivity laser induced fluorescence

New Ranking of Generalized Quadrilateral Shape Fuzzy Number Using centroid Technique

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Intelligent Automation & Soft computing 2023年第5期36卷 2253-2266页

作者： A.Thiruppathi c.k.kirubhashankar Department of Mathematics Sathyabama Institute of Science and TechnologyChennai600119TamilnaduIndia

The output of the fuzzy set is reduced by one for the defuzziﬁcation *** is employed to provide a comprehensible outcome from a fuzzy inference *** page provides further information about the defuzziﬁca-tion approach for quadrilateral fuzzy numbers,which may be used to convert them into discrete ***ﬁcation demonstrates how useful fuzzy ranking systems can *** major purpose is to develop a new ranking method for gen-eralized quadrilateral fuzzy *** primary objective of the research is to provide a novel approach to the accurate evaluation of various kinds of fuzzy *** ranking properties are *** the counterexamples of Lee and chen demonstrates the fallacy of the ranking ***,a new approach has been developed for dealing with fuzzy risk analysis,risk management,indus-trial engineering and optimization,medicine,and artiﬁcial intelligence problems:the generalized quadrilateral form fuzzy number utilizing centroid *** you can see,the aforementioned scenarios are all amenable to the solution pro-vided by the generalized quadrilateral shape fuzzy number utilizing centroid ***’s laid out in a straightforward manner that’s easy to grasp for *** rating method is explained in detail,along with numerical exam-ples to illustrate *** but not least,stability evaluations clarify why the Gener-alized quadrilateral shape fuzzy number obtained by the centroid methodology outperforms other ranking methods.

关键词： Fuzzy numbers quadrilateral fuzzy number ranking methods fuzzy risk analysis

ScHEDULING TWO GROUPS OF JOBS WITH INcOMPLETE INFORMATION

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Systems Science and Systems Engineering 2003年第1期12卷 73-81页

作者： GuochuanZHANG XiaoqiangcAI c.k.WONG DepartmentofMathematics ZhejiangUniversityHangzhou30027P.R.China DepartmentofSystemsEngineeringandEngineeringManagement TheChineseUniversityofHongKongShatinN.T.HongKong DepartmentofcomputerScienceandEngineering TheChineseUniversityofHangKongShatinN.T.HongKong

In real world situations, most scheduling problems occur neither as complete off-line nor as complete on-line models. Most likely, a problem arises as an on-line model with some partial information. In this article, we consider such a model. We study the scheduling problem P(n1,n2), where two groups of jobs are to be scheduled. The first job group is available beforehand. As soon as all jobs in the first group are assigned, the second job group appears. The objective is to minimize the longest job completion time (makespan). We show a lower bound of 3/2 even for very special cases. Best possible algorithms are presented for a number of cases. Furthermore, a heuristic is proposed for the general case. The main contribution of this paper is to discuss the impact of the quantity of available information in designing an on-line algorithm. It is interesting to note that the absence of even a little bit information may significantly affect the performance of an algorithm.

关键词： Machine scheduling worst-case analysis on-line algorithm

精神病临床高危人群的症状和功能改变:一项系统综述和三水平元分析

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心理科学进展 2025年第1期33卷 42-61页

作者：赵子卿余锦婷陈嘉彦王芸茹黄佳陈楚侨中国人民大学心理学系北京100872 北京体育大学心理学院北京100091 中国科学院心理研究所心理健康重点实验室神经心理学与应用认知神经科学实验室北京100101 中国科学院大学心理学系北京100101

精神病临床高危(clinical high-risk for psychosis,cHR-P)人群的症状和功能发展存在异质性,澄清这个群体症状和功能的改变及联系,有利于精神病早期预防。元分析纳入54篇文献,探究cHR-P人群各维度临床症状和功能的纵向改变、基线症状对... 详细信息

精神病临床高危(clinical high-risk for psychosis,cHR-P)人群的症状和功能发展存在异质性,澄清这个群体症状和功能的改变及联系,有利于精神病早期预防。元分析纳入54篇文献,探究cHR-P人群各维度临床症状和功能的纵向改变、基线症状对随访功能的预测作用、调节效应。结果发现,cHR-P人群轻微阳性症状、阴性症状、瓦解症状、情感症状、一般精神病理症状、整体功能和角色功能随时间显著改善,社会功能没有显著改善;基线阴性症状显著负向预测随访的整体功能、社会功能、角色功能,基线的瓦解症状、情感症状、一般精神病理症状与随访的整体功能显著负相关;受教育程度显著调节轻微阳性症状和阴性症状的纵向变化,年龄、轻微阳性症状亚组比例和短暂间歇性精神病性症状亚组比例显著调节情感症状的纵向变化。这揭示阴性症状改善少和社会功能损害是cHR-P人群的核心特征,提示未来可针对阴性症状研发干预措施,进而改善社会功能。

关键词：精神病临床高危人群纵向改变三水平元分析阴性症状社会功能

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Physical and mechanical properties of klainedoxa gabonensis with engineering potential

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Journal of Forestry Research 2017年第3期28卷 629-636页

作者： k.Boakye Boadu c.Antwi-Boasiako k.Frimpong-Mensah Department of Wood Science&Technology Faculty of Renewable Natural ResourcesKwame Nkrumah University of Science&TechnologyKumasiGhana

Adequate information is sparse for many tropical timbers on their engineering applications, which make their international promotion difficult. The physical and mechanical properties of klainedoxa gabonensis Pierre ex Engl. （a lesserutilized species） and Entandrophragma cylindricum were compared. k. gabonensis contained more moisture with greater density at 12 % moisture content than E. cylindricum and had a tangential-radial ratio for swelling and shrinkage of 1.31-1.38 and 1.58-1.63, respectively, within acceptable thresholds for engineering/structural timbers. For k. gabonensis, shear parallel to grain was 32.2 ± 0.4-33.5 ±1 N mm^-2; compressive parallel to grain, 80.7 ± 1.4-90.6± 1 N mm^-2; modulus of rupture, 204± 4.0-214 ± 4.0 N mm^-2 and modulus of elasticity, 28,932 ± 664-29,493 ±822 N mm^-2. These properties were superior to those of E. cylindricum [（15.5 ± 0.9）- （15.6 ± 0.6）, （56.4 ± 4.5）-（63.6 ± 1.2）, （99.4 ± 4.7）- （121.3 ± 10.6）, and （9987.4 ± 207）-（10,051 ± 258） N mm^-2, respectively] and compared well with those of several traditional timbers for conslruction and furniture production. Its use would contribute to minimize pressure on the primary timbers in the forests and widen the raw material base for wooden products.

关键词： Density Dimensional stability Timberengineering Mechanical property Tangential-radialratio Traditional timber

Deformation behavior of Zr-based bulk metallic glass and composite in the supercooled liquid region

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Science china(Physics,Mechanics & Astronomy) 2008年第4期51卷 349-355页

作者： cHEN Qi LIU Lin cHAN k.c. State key Laboratory of Die&Mould Technology Huazhong University of Science and TechnologyWuhan 430074China Department of Industrial and Systems Engineering Hong Kong Polytechnic UniversityHong KongChina

A Zr-based bulk metallic glass (BMG) with a composition of (Zr75cu25)78.5Ta4Ni10Al7.5 and a bulk metallic glass matrix composite (BMGc) with a composition of (Zr75cu25)74.5Ta8Ni10Al7.5 have been prepared by copper-mold casting. The compres-sive deformation behavior of the BMG and BMGc was investigated in the super-cooled region at different temperatures and various strain rates ranging from 8×10-4s-1 to 8×10-2s-1. It was found that both the strain rate and test temperature signifi-cantly affect the deformation behavior of the two alloys. The deformation follows Newtonian flow at low strain rates but non-Newtonian flow at high strain rates. The deformation mechanism for the two kinds of alloys was discussed in terms of the transition state theory.

关键词： bulk metallic glass composites supercooled liquid region compressive deformation free volume

Modelling and mapping third dimension in a spatial database

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International Journal of Digital Earth 2011年第6期4卷 505-520页

作者： F.Donera c.Bıyık Department of Geomatics Engineering Gumushane UniversityGumushaneTurkey Department of Geomatics Engineering Karadeniz Technical UniversityTrabzonTurkey

In this paper,an overview of phases for modelling and mapping third dimension of spatial objects in a database is presented based on a selected spatial database management system(DBMS).These phases include(1)defining a spatial reference system for representing three-dimensional(3D)objects with real-world coordinates,(2)geometric modelling of 3D objects in the database,(3)3D spatial indexing for fast accessing/querying the 3D data,3D spatial queries and representation of 3D ***,a case study is performed to assess needs,possibilities and potential limitations of 3D data modelling in the spatial database.

关键词： spatial database geo-data 3D data modelling GIS digital earth

The Weakly Potency of certain HNN Extensions of Nilpotent Groups

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Algebra colloquium 2014年第4期21卷 689-696页

作者： k.B. Wong P.c. Wong Institute of Mathematical Sciences University of Malaya 50603 Kuala Lumpur Malaysia

In this paper we give a characterization for certain HNN extensions oi suogroup separable groups with normal associated subgroups to be weakly potent. We then apply our result to show that certain HNN extensions of fi... 详细信息

关键词： weakly potent HNN extensions subgroup separable finitely generated nilpo-tent groups

THE 1-LAPLAcIAN cHEEGER cUT： THEORY AND ALGORITHMS

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Journal of computational Mathematics 2015年第5期33卷 443-467页

作者： k.c. chang Sihong Shao Dong Zhang LMAM and School of Mathematical Sciences Peking University Beijing 100871 China

This paper presents a detailed review of both theory and algorithms for the cheeger cut based on the graph 1-Laplacian. In virtue of the cell structure of the feasible set, we propose a cell descend （cD） framework for achieving the cheeger cut. While plugging the relaxation to guarantee the decrease of the objective value in the feasible set, from which both the inverse power （IP） method and the steepest descent （SD） method can also be recovered, we are able to get two specified cD methods. comparisons of all these methods are conducted on several typical graphs.

关键词： Spectral graph theory Spectral clustering 1-Laplace operator Graph Lapla-cian Eigenvalue problems cheeger constant Graph cut Optimization convergence