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A　BRANcH-AND-PRIcE　ALGORITHM　FOR　SOLVING　THE　cUTTING　STRIPS　PROBLEM

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Applied Mathematics(A Journal of chinese Universities) 1997年第2期12卷 215-224页

作者： cHENZHIPING c.A.J.HURKENS J.L.DEJONG DepantmeatofMathematicsandcomputingSciences EindhovenUniversityofTechnologyTheNertherlands. DepartmentofMathematicsandcomputingSciences EindhovenUniversityofTechnologyTheNertherlands. DepartmeatofMathematics Xi＇anJiaotongUniversityXi＇an710049.

After giving a suitable model for the cutting strips problem, we present a branch and price algorithm for it by combining the column generation technique and the branch and bound method with LP relaxations. Some theoretical issues and implementation details about the algorithm are discussed, including the solution of the pricing subproblem, the quality of LP relaxations, the branching scheme as well as the column management. Finally, preliminary computational experience is reported.

关键词： cutting strips problem column generation branch-and-bound

A Boundary Meshless Method for Solving Heat Transfer Problems Using the Fourier Transform

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Advances in Applied Mathematics and Mechanics 2011年第5期3卷 572-585页

作者： A.Tadeu c.S.chen J.Antonio Nuno Simoes Department of civil Engineering Faculty of Sciences and TechnologyUniversity of CoimbraPolo II-Pinhal de Marrocos3030-290 CoimbraPortugal Department of Mathematics University of Southern MississippiHattiesburgMS 39406USA

Fourier transform is applied to remove the time-dependent variable in the diffusion *** non-harmonic initial conditions this gives rise to a non-homogeneous Helmholtz equation,which is solved by the method of fundamental solutions and the method of particular *** particular solution of Helmholtz equation is available as shown in[4,15].The approximate solution in frequency domain is then inverted numerically using the inverse Fourier transform *** frequencies are used in order to avoid aliasing phenomena and to allow the computation of the static *** numerical examples are given to illustrate the effectiveness of the proposed approach for solving 2-D diffusion equations.

关键词： Transient heat transfer meshless methods method of particular solutions method of fundamental solutions frequency domain Fourier transform

Studies on the Lattice Distortion and Substructures of Shocked Lamellae in Naturally Shocked Quartz

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Acta Geochimica 1987年第1期6卷 19-32页

作者：谢先德 EDWARD c. T. cHAO Institute of Geochemistry Academia Sinica United States Geological Survey Mailstop 929 Reston Va 22092 United States of America

One unshocked and 9 naturally shocked single quartz crystal grains with 1-6 sets of shock lamellaefrom the Ries, West Germany, and the Lake Lappajarvi, Finland, covering a range from unshocked quartzwith _disibledevent=1.544 to nearly completely glassy quartz with _disibledevent=1.461 have been used for X-ray precessionand Laue investigations. Four of the shocked grains have preliminarily been studied under a transmissionelectron microscope. It is found that quartz having No less than 1.539 shows intensive anisotropic cellexpansion and lattice disordering which gradually increase as No decreases. Shock-induced lattice distortionof quartz is clearly shown on both precession and Laue photographs. For the weakly shocked quartz (pced spreading of spots is observed. When the pressure reaches 200 kb, both concentricspreading of spots having long ‘tails' and concentric rings (powder pattern) are revealed on the samephotograph, which means that besides a part of single crystal there also exist randomly oriented tiny‘fragments' of quartz in this shocked quartz grain. As pressure increases from 230 to 315 kb, more and morecrystalline puases in the quartz grains have transformed from solid state into silica glass, and the concentricrings and the long ‘tails' disappear and the spot spreading becomes slight again, but reflection intensitiesbecome much lower in comparison with those of weakly shocked quartz. TEM investigations show three kinds of substructures of shock lamellae. The glass contents of two ofthe four grains (73% and 84% respectively) were measured on TEM photographs with the help of an imageanalysis system. On the basis of above investigations a six-terminal-state model for the mechanism of deformation inshock metamorphosed quartz is presented.

关键词： Studies on the Lattice Distortion and Substructures of Shocked Lamellae in Naturally Shocked Quartz

Effects of high temperature treatment at initial stage of anther culture on culture responses in wheat

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chinese Science Bulletin 1997年第17期42卷 1472-1476页

作者： Liang, H Ouyang, JW Jia, SE Zhang, c Jia, X AcAD SINIcA GENET INSTBEIJING 100101PEOPLES R CHINA

cULTURE temperature is an important factor in anther culture. In our laboratory we have made intensive studies on this problem, and found that the responses of anther culture to culture temperature were not only sensi... 详细信息

关键词： wheat anther culture culture temperature.

The brazing of diamond

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金刚石与磨料磨具工程 2008年第S1期28卷 134-142页

作者： Sung Michael Sung James c. Advanced Diamond Solutions Inc.351 King Street Suite 813San FranciscoCA 94158U.S.A. KINIK company 64Chung-San Rd.Kuo-Ying National Taiwan UniversityTaipei 106 Taiwan National Taipei University of Technology

Diamond grits held in metal matrix(sintered or electroplated) are retained primary by mechanical *** of this weak attachment,the pullouts of diamond from matrix are inevitable during the cutting ***,the working grits have low protrusion heights,so the cutting speed of the tool is limited. Furthermore,the rubbing of metal matrix and the work object can cause thermal damages of diamond and other materials,and power increase for the operation. Diamond can be firmly held in a metal matrix by *** of the presence of strong chemical bonding,diamond grits can protrude twice as high without being knocked off from the *** a result,the cutting speed of the tool may be doubled. When the braze melts,the carbide formers will migrate toward diamond to form carbide at the interface. This reaction may be excessive as to degrade diamond *** this case,a coating on diamond may be needed to moderate the reaction. When diamond is brazed on the surface of a substrate,the melt tends to pull the grits closer together that may thicken the braze layer *** clustering of grits can reduce the cutting effectiveness of the diamond tool.A diamond grid design is necessary to maintain the uniform thickness of the braze ***,the controlled melting of braze alloy can form a gentle slope around each diamond *** a massive support can allow aggressive cutting of the diamond tool with a low power consumption.

关键词： diamond brazing diamond dresser pad conditioner diamond adherence diamond distribution chemical mechanical planarization

Tertiary lymphoid structures in cancer – considerations for patient prognosis

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cellular & Molecular Immunology 2020年第6期17卷 570-575页

作者： Luis Munoz-Erazo Janet L.Rhodes Valentine c.Marion Roslyn A.Kemp Department of Microbiology and Immunology University of OtagoDunedinNew Zealand Ecole Normale Superieure de Lyon LyonFrance and Universite Claude Bernard Lyon 1LyonFrance

Tertiary lymphoid structures(TLS)are ectopic lymphoid formations that form within nonlymphoid *** share structural and functional characteristics with secondary lymphoid structures such as lymph nodes and can contain B-cell follicles and germinal centers surrounded by a T-cell *** have been described in several types of cancers and are usually associated with positive patient ***,TLS differ vastly in cellular composition and location within tissue *** this review,we discuss factors confounding the interpretation of the evidence for a prognostic role for TLS in cancer and frame these factors in the context of translation to regular clinical use.

关键词： tertiary lymphoid structure prognosis cancer tissue

Multi-Pass Simulation of Heavy Plate Rolling Including Intermediate Forced cooling

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Journal of Iron and Steel Research International 2011年第S1期18卷 506-510页

作者： E.J.Palmiere A.A.Howe H.c.carey Institute for Microstructural and Mechanical Process Engineering:The University of Sheffield (IMMPETUS) Sir Robert Hadfield BuildingMappin StreetSheffieldS1 3JDUK Tata Steel Research Development &Technology Swinden Technology CentreMoorgateRotherham S60 3ARUK

Thermomechanical controlled Processing (TMcP) including accelerated cooling after the final hot rolling pass is a well-established technology,widely applied in HSLA steel plate ***,there are still certain limitations,especially for thicker *** rolling schedule includes a long holding period (HP) after the roughing stage to allow the temperature to fall sufficiently for optimised TMcP during *** Forced cooling (IFc) applied during the HP can increase productivity by decreasing the required hold time,can restrict austenite grain growth,and can also improve the subsequent strain penetration in thick plate with further metallurgical ***-pass plane strain compression (PSc) tests have been performed on the thermomechanical compression (TMc) machine at Sheffield University including different severities of *** it is impossible to simulate all aspects of the temperature and strain gradients present in thick plates in laboratory specimens,and most of the tests were conducted at temperatures and strains calculated by Finite Element modelling as relevant to specific positions through the plate ***,some aspects of the gradients were addressed with tests using cold *** results have indeed shown that IFc can shorten the HP and reduce austenite grain growth and its variation across thick plate.

关键词： Steel plate rolling intermediate forced cooling plane strain compression recrystallisation grain growth finite element modelling temperature and strain distribution

cOMPARISON OF LINEAR AND NONLINEAR WAVES ASSOcIATED WITH STEADY-STATE FORcING SOURcES

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Acta meteorologica Sinica 1990年第5期4卷 650-660页

作者：雷兆崇 c.N.Duncan Nanjing Institute of Meteorology Nanjing Department of Meteorology University of Edinburgh U.K.

Low-frequency phenomena in the atmosphere are intimately related to stationary waves and, in a sense, the former may even be viewed as the time-varying part of the quasi-stationary waves themselves, Much attention has been focused on nonlinear interactions in the conceptual study on stationary waves. Linear and nonlinear primitive-equation baroclinic spectral models are adopted to investigate the response of stationary waves to large- scale mechanical forcing and steady-state thermal forcing, both idealized and realistic, followed by calculations of the EP fluxes and three-dimensional wave activity fluxes (Plumb, 1985) for both the linear and nonlinear solu- tions. Results show that when the forcing source grows intense enough to be comparable to the real one, non- linear interaction becomes very important, especially for the maintenance of tropical and polar stationary waves. care should be taken, however, in using the EP flux and Plumb's 3-D flux for diagnostic analysis of observational data as they are highly sensitive to nonlinear interaction.

关键词： cOMPARISON OF LINEAR AND NONLINEAR WAVES ASSOcIATED WITH STEADY-STATE FORcING SOURcES

Gangrenous cholecystitis: A silent but potential fatal disease in patients with diabetic neuropathy. A case report

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World Journal of clinical cases 2018年第15期6卷 1007-1011页

作者： Melorin Mehrzad charles c Jehle Lauren O Roussel Raman Mehrzad Department of Plastic and Reconstructive Surgery Rhode Island Hospital Brown University

Gangrenous cholecystitis(Gc) is a severe and potentially deadly complication of acute cholecystitis. We present a 83-year-old gentleman with a past medical history of type 2 diabetes mellitus with significant associated neuropathy, presenting to a community hospital in a major metropolitan area with 10 days nausea and vomiting and a benign abdominal exam. While the patient was admitted for hyperglycemia, he was subsequently found to have severe Gc requiring urgent surgical intervention.

关键词： Gangrenous cholecystitis Diabetes mellitus Hyperglycemia complications case report