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Layer-layout-based heuristics for loading homogeneous items into a single container

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第12期8卷 1944-1952页

作者： wANG Zhou-jing li Kevin w Department of Automation Xiamen University Xiamen 361005 China Odette School of Business University of Windsor Windsor Ontario N9B 3P4 Canada

The container loading problem (CLP) is a well-known NP-hard problem. Due to the computation complexity, heuristics is an often-sought approach. This article proposes two heuristics to pack homogeneous rectangular boxes into a single container. Both algorithms adopt the concept of building layers on one face of the container, but the first heuristic determines the layer face once for all, while the second treats the remaining container space as a reduced-sized container after one layer is loaded and, hence, selects the layer face dynamically. To handle the layout design problem at a layer's level, a block-based 2D packing procedure is also developed. Numerical studies demonstrate the efficiency of the heuristics.

关键词： Container loading problem (CLP) Heuristic Laver Packing. Optimization

PREDICTION OF CHARACTERISTICS FOR VERTICAL ROUND NEGATIVE BUOYANT JETS IN HOMOGENEOUS AMBIENT

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Journal of Hydrodynamics 2001年第1期13卷 103-110页

作者： Huai, w.X. li, w. Dep. of River Eng. Coll. of Water Resource Eng. Wuhan 430072 China

The k-Ε turbulence model is used to establish a mathematical model of a vertical round jet with negative buoyancy in a static homogeneous ambient. The hybrid finite analytic method, with a non-uniform staggered grid, is used to calculate the whole flow field. The variations of centerline velocity, density and turbulent kinetic energy along the axial line for a given exit densimetric Froude number are found to converge to single curves under the unified scaling law derived by Chen and Rodi. The profiles of mean velocities, mean density difference and the half-width of negative buoyant jets for velocity and density are given. The calculation confirmed that the maximum height of rise is proportional to M03/4 B0-1/2, where M0 and B0 are the momentum flux and the buoyancy flux at the source, respectively.

关键词： Computer simulation Jets Mathematical models Numerical methods

A NOVEL APPROACH TO CHARACTERIZING HESITATIONS IN INTUITIONISTIC FUZZY NUMBERS

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Journal of Systems Science and Systems Engineering 2013年第3期22卷 283-294页

作者： Minji HUANG Kevin w.li Department of Automation Xiamen University Odette School of Business University of Windsor

Building upon the concept of Dα operator introduced by Atanassov （1989）, thin article proposes an improved objective approach and a hybrid approach to operationalize Dα so that the hesitation in an intuitionistic fuzzy number （IFN） can be further refined and characterized. Numerical experiments are carried out to demonstrate the features and novelty of the proposed approach compared to existing methods in the literature. The aim is to furnish an effective way to refine hesitations in intuitionistic fuzzy assessments for more reliable and confident decision aids.

关键词： Intuitionistic fuzzy numbers fuzzy numbers hesitation Dα operator

GROwTH KINETICS OF SINGLE INCLUSION PARTICLE IN MOLTEN MELTS

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Acta Metallurgica Sinica(English Letters) 2007年第2期20卷 129-138页

作者： B.w. Zhang B.w. li Department of Materials and Metallurgy Inner Mongolia University of Science and Technology Baotou 014010 China

On the basis of the single-particle framework, a new theory on inclusion growth in metallurgical melts is developed to study the kinetics of inclusion growth on account of reaction and collision. The studies show that the early growth of inclusion depends on reaction growth and Brawnian motion collision, and where the former is decisive, the late growth depends on turbulence collision and Stokes＇ collision, and where the former is dominant; collision growth is very quick during the smelting process, lessened in the refining process, but nearly negligible in the continuous casting process.

关键词： inclusion growth reaction collision kinetics

NOTES ON “MULTICRITERIA FUZZY DECISION-MAKING METHOD BASED ON A NOVEL ACCURACY FUNCTION UNDER INTERVAL-VALUED INTUITIONISTIC FUZZY ENVIRONMENT”

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Journal of Systems Science and Systems Engineering 2010年第4期19卷 504-508页

作者： Kevin w. li Zhoujing wANG Odette School of Business University of Windsor Windsor Ontario N9B 3P4 Canada School of Computer Science and Engineering Beihang University Beijing 100083 China Department of Automation Xiamen University Xiamen Fujian 361005 China

This note points outs the inappropriateness of an accuracy function introduced by Ye [Ye, J. （2009）. Multicriteria fuzzy decision-making method based on a novel accuracy function under interval-valued intuitionistic fuzzy environment. Expert Systems with Applications, 36 （3）： 6899-6902] and its misleading use for comparing two interval-valued intuitionistic fuzzy numbers.

关键词： Interval-valued intuitionistic fuzzy set accuracy function score function multicriteria decision-making

COMPARISON OF K-ε AND K-ω TURBULENCE MODELS FOR SIMULATION OF SHALLOw RECIRCULATING FLOwS IN AN OPEN CHANNEL

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Journal of Hydrodynamics 1998年第2期10卷 74-86页

作者： Zhang, Yifan li, C.w. Nanjing Hydraulic Research Inst Nanjing China

The paper describes the comparison of commonly used k-ε and k-ω turbulence models for simulating the recirculating flows behind a sudden expansion in a straight open channel. The depth-average numerical model and the quasi three-dimensional multilayer model are presented respectively. The governing equations are split into three parts in the finite difference approach: advection, dispersion and propagation. Comparison of the results computed with the k-ε and k-ω models shows that the two turbulence models have strong robustness in simulating the reattachment length of the recirculating flows. The computed results are found in good agreement with the measured data.

关键词： turbulence k-ω modek k-ε model finite difference channel expansion

Studies　on　Porphyrin　and　Phthalocyanine　Monolayers　by　Means　of　Compression－Recompression　Isotherms　and　BAM

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Chinese Chemical Letters 1996年第11期7卷 1041-1042页

作者： wang, wS li, w Xi, SQ CHINESE ACAD SCI CHANGCHUN INST APPL CHEMCHANGCHUN 130022PEOPLES R CHINA

Monolayers of porphyrin and phthalocyanine at the air-water interface were studied bymeans of film balance and Brewster angle microscopy (BAM). ResultS showed that the final point ofcompression isotherm and that of recompression isotherm were coincident or not coincidentdepending on the target pressures. Results were discussed in terms of the morphology of monolayersobserved by BAM.

关键词： BAM and Isotherms Means Monolayers Phthalocyanine Porphyrin Studies Recompression

The Transient Time-Resolved Absorption Spectra of 1-Naphthylacetic Acid

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Chinese Chemical Letters 2000年第3期11卷 261-262页

作者： li, w Tung, CH Ye, JP Chinese Acad Sci Inst Photog Chem Beijing 100101 Peoples R China

The transient absorption spectra of 1-naphthylacetic acid in tetrahydrofuran have been obtained by laser flash photolysis technique. The transient species bands are at 509, 535 and 553 nm. These peak intensities incre... 详细信息

关键词： transient spectra laser chemistry 1-naphthylacetic acid

Effect of cholecystokinin and secretin on contractile activity of isolated gastric muscle strips in guinea pigs

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world Journal of Gastroenterology 2000年第1期6卷 93-95页

作者： li w Zheng TZ Qu SY Department of Physiology Lanzhou Medical CollegeLanzhou 730000Gansu ProvinceChina

AIM To study the effect of cholecystokinin-octapeptide（CCK-8）and secretin on contractileactivity of isolated gastric muscle strips inguinea *** Each isolated gastric muscle stripwas suspended in a tissue chamber containing5 mL Krebs solution constantly warmed by waterjacked at 37℃ and supplied with a mixed gas of95% O2 and 5% CO2 After incubating for lhunder 1 g tension,varied concentrations of CCK-8 and secretin were added respectively in thetissue chamber and the contractile response wasmeasured isometrically on ink-writing *** CCK-8 could increase①all regionalcircular and longitudinal muscular tension at rest（fundus LM 19.7%±2.1%,Plitude of antral circular muscle（58.6%±18.4%,Plity index ofpylorus CM（145.0%±23.8%,Plitude ofgastric body and antral LM（-10.3%±3.3%,-10.5%±4.6%,respectively,P were not blocked by atropine *** had no effect on gastricsmooth muscle *** CCK-8 possessed bothexcitatory and inhibitory action on contractileactivity of different regions of stomach in *** action was not mediated via cholinergicM receptor and endogenous prostagiandinreceptor,

关键词： Subject headings gastric muscle strips cholecystokinin secretin guinea pigs