检索结果-南通市图书馆

Asphalt　fractions　in　airborne　particles　from　highway　traffic　and　the　accumulation　in　plants

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Journal of Environmental Sciences 1996年第2期8卷 196-202页

作者： He Kebin(department of Environmental Engineering, Tsinghua University, Beijing 100084,china)Hans Mosbaek Jens Chr. Tjell(department of Environmental Engineering,technical University of Dentnark, 2800 Lyngby,Denmark) Dept. of Environmental Engineering Tsinghua University Beijing 100084 China Dept. of Environmental Engineering Technical University of Denmark 2800 Lyngby Denmark

With reference to ASTM D4124, asphalt fractions, including polar aromatics (polars),naphthene aromatics (aromatics) and saturates,were characterized both in airborne particles collected in the distances of 2.0 -83.6m from the highway and in the plant samples (including grass,leaves and wheat straw) collected in the distance of 2.0 -10. 0m from the highway. In comparison to the results of diesel particulate, background plant samples and asphalt cernent samples from highway surface, it is concluded that there could be asphalt rnatters in airborne particles and asphalt makes the rnain contributions to the accumulation of the three factions mentioned above in plant species. In the ambient air,the concentrations of the three asphalt fractions are 0. 54- 3.06 ×10-3 mg polars,1. 77- 9. 50 × 10-4 mg aromatics and 0. 21- 1. 23 × 10-4 mg saturates for per cubic meter air. The percentage of bitumen in airborne particles is 1. 61%-11. 02%. In the plant samples, the concentrations are 0. 29- 3.07mg polars, 0.89- 3.89 aromatics and 0. 37-1. 53 mg saturates for per gram dry plant materials.

关键词： asphalt airborne particle traffic pollution HPLC.

A Modified Filter Trust Region Method for Nonlinear Programming

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A Modified Filter Trust Region Method for Nonlinear Programm...

DNA Supercomputing of Multiprocessor’s Independent Task Scheduling Problem

第二十六届中国控制会议

作者： Su Ke1,2 1.department of mathematics,Tongji University,Shanghai 200092,P.R.china 2.college of mathematics and computer,Hebei University,Baoding 071002,P.R.china

Sequential quadratic programming（SQP）type method is one of the most effective methods for solving nonlinear ***,filter method,for its good numerical results,are extensively studied to handle nonlinear programming *** this paper,a new modified approach combined the filter technique and SQP trust region method is proposed to tackle the original problem,which ensures that every trail point will not be far away from the feasible *** convergence results of the proposed algorithm are established under suitable *** numerical results are reported in this paper.

关键词： Filter Method Trust Region Sequential Quadratic Programming Nonlinear Programming

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DNA Supercomputing of Multiprocessor’s Independent Task Sch...

Hausdorff centered measure of certain linear Cantor sets

2011年全国电子信息技术与应用学术会议

作者： Jianbo WANG department of computer Science and Technology Hunan Institute of Humanities,Science and Technology Loudi,china Guangjun GUO,Xinbo CHEN department of Electric and Electrical Engineering Loudi vocational and technical college Loudi,china

Task scheduling is a NP-hard problem and is an integral part of parallel and distributed *** this paper,implementation ideas and methods to solve independent task scheduling problem which is an engineering related combinatorial problem using this DNA computing approach is *** objective of solution of the independent task scheduling problem is to find an optimal scheduling that can satisfy with resources load *** proposed algorithms show promising results that DNA computing approach can be well-suited for solving such real-world application in the near future.

关键词： DNA computing task scheduling NP-hard problem parallel computing

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Progress in Natural Science:Materials International 2005年第4期 10-16页

作者： PENG Li 1* and WU Min 2(1. department of mathematics, Hubei University, Wuhan 430062, china 2. department of Applied mathematics, South china University of Technology, Guangzhou 510640, china) department of mathematics Hubei University Wuhan 430062 China department of Applied mathematics South China Uni-versity of Technology Guangzhou 510640 China

In this paper, we study the Hausdorff centered measure of certain linear Cantor sets. We establish the relationship between the Hausdorff centered measure of this set and the maximum centered density of the corresponding self similar measure. From this relationship, the Hausdorff centered measure of certain sets is obtained. In particular, we consider the linear iterated function system consisting of three maps with the same contraction ratios. Under some technical restrictions, we determine the exact Hausdorff centered measure of its attractor.

关键词： Hausdorff centered measure packing measure Cantor set.

Research on Fault Diagnosis Method of Principal Components Analysis and D-S Evidence Theory

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Research on Fault Diagnosis Method of Principal Components A...

通用图书查重系统研制开发设计原理及其实现方法

2009中国控制与决策会议

作者： Peng Tong~(),Lian-suo An~2,Ji Zhang~3,Yu-tao Liu~4 1.department of Power Engineering,Baoding technical college of Electric Power,Baoding 071003,china 2.department of Power Engineering,North china Electric Power University,Baoding 071003,china 3.department of computer,North china Electric Power University,Baoding 071003,china 4.department of mathematics & Physics,North china Electric Power University,Baoding 071003,china

＜正＞According to the problem of amount and complexity of calculation exponent increased with the measurement dimension increment when multi-data source related by D-S Fusion arithmetic,a fault diagnosis method combined PCA and D-S evidence theory is ***,the characteristic of data dimension reduction of PCA and the completeness of fault diagnosis and the advantage of presenting and reasoning inaccurate information of evidence theory are utilized, and the problem of non-uniqueness of fault isolation of PCA and combination explosion of evidence theory is solved. And calculation amount and complexity are reduced quit,and the simulation study on boiler feed water control system shows that the fault of sensor can be isolated correctly and effectively by this method.

关键词： fault diagnosis D-S evidence theory principal components analysis power plant

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图书馆论坛 2005年第1期25卷 74-76页

作者：吕刚揭阳学院图书馆广东揭阳522000

针对目前人工图书查重繁琐、费时的具体问题, 提出了通用图书查重系统研制开发的设计原理及关键技术的实现方法, 从而使图书查重更方便、更省时省力, 同时还解决了现场采购图书的查重问题。

关键词：图书查重现场采购省力具体问题省时实现方法开发设计通用设计原理关键技术

Theoretical calculation of the finishing rolling elongation in alloying non-quenched and tempered steel

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Progress in Natural Science:Materials International 2006年第8期16卷 859-867页

作者： LIU Zhilin, LIN Cheng and GUO Yanchang (department of Materials and Chemical Engineering, Liaoning Institute of Technology, Jinzhou 121001, china The technical Center of Benxi Iron and Steel Group Corporation, Benxi 117000, china) [a]department of Materials and Chemical Engineering Liaoning Institute of Technology Jinzhou China [b]The technical Center of Benxi Iron and Steel Group Corporation Benxi China

The finishing rolling elongationδof the alloying non-quenched and tempered steel is calculated with the covalent electron number nA of the strongest bond of the alloying phases and the interface electron density differenceΔρof the phase interfaces. The calculations show that the elongationδα-Fe of the matrixα-Fe decreases with rolling refinement, the elongationδα-Fe-C-M of solid solution phases (M denotes alloying element) is inversely proportional to the covalent electron number nAα-Fe-C-M of the strongest bond, the elonga tion decrementΔδα-Fe/α-Fe-C-M caused by interface strengthening is directly proportional to the interface electron density differenceΔρα-Fe/α-Fe-C-M, but the elongation decrementsΔδα-Fe/MCC1 andΔδα-Fe-C/MCC2 caused by dispersion strengthening and precipitation strength- ening respectively are directly proportional to the ratio of the electron density differenceΔρα-Fe/MCC1 andΔρα-Fe/MCC2 of the strengthening interfaces toΔρα-Fe/α-Fe-C of the basic interfaceα-Fe/α-Fe-C. Therefore, the finishing rolling elongation of the alloying non-quenched and tempered steel is considered to be subtracting all the elongation decrements of solution strengthening, interface strengthening, dispersion strengthening and precipitation strengthening from the elongation of the refinedα-Fe matrix. The calculation formulas in this paper are integrated with the proposed ones ofσS,σb and ofαK delivered in another paper, the finishing rolling mechanical properties can be achieved and the calculated results agree well with the measured ones.

关键词： electron structure parameters alloying non-quenched and tempered steel elongation theoretical calculation.

Volume Change of Heterogeneous Quasi-brittle Materials in Uniaxial Compression

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Journal of Wuhan University of Technology(Materials Science) 2006年第3期21卷 162-167页

作者：王学滨 department of Mechanics and Engineering Sciences Liaoning Technical University Fuxin 123000China

The volumetric strain was categorized into elastic and plastic parts. The farmer camposed of axial and lateral strains is uniform and determined by Hooke＇s law ; however, the latter consisting of axial and lateral strains is a fuaction af thickness af shear band determined by grndieat-dependeat plasticity by cansidering the heterngeneity of quasi- brittle materials. The non- uniform lateral strain due to the fact that shear band was farmed in the middle of specimen was averaged within specimen to precisely assess the volumetric strain. Then, the analytical expression for volumetric strain was verified by comparison with two earlier experimental results for concrete and rack. Finally, a detailed parametric study was carried out to investigate effects of constitutive parameters （ shear band thickness, elastic and softening rnoduli ） and geometrical size of specimen（ height and width of specimen ） on the volume dilatancy.

关键词： quasi-brittle material heterogeneity volume dilatancy axial compression strain localization non-uniformity of lateral strain shear band thickness

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■-二重粗积分与系统识别

山东大学学报（理学版） 2009年第3期44卷 92-96页

作者：吕昆山东城市建设职业学院基础部山东济南250014 山东大学数学学院山东济南250100

以函数单向S-粗集对偶的上、下近似生成的函数为基础,提出了粗区域的定义,二重粗积分的定义及其动态特征,通过动态特征给出了扩张度和扩张率的概念,并且通过计算扩张度和扩张率来度量系统受干扰的程度。

关键词：函数单向S-粗集对偶粗区域二重粗积分扩张度扩张率系统识别