Showing papers by "Wrocław University of Technology published in 1996"
TL;DR: A fast and easily implementable approximation algorithm for the problem of finding a minimum makespan in a job shop is presented, based on a taboo search technique with a specific neighborhood definition which employs a critical path and blocks of operations notions.
Abstract: A fast and easily implementable approximation algorithm for the problem of finding a minimum makespan in a job shop is presented. The algorithm is based on a taboo search technique with a specific neighborhood definition which employs a critical path and blocks of operations notions. Computational experiments up to 2,000 operations show that the algorithm not only finds shorter makespans than the best approximation approaches but also runs in shorter time. It solves the well-known 10 × 10 hard benchmark problem within 30 seconds on a personal computer.
964 citations
TL;DR: A fast and easily implementable approximation algorithm for the problem of finding a minimum makespan in the permutation flow shop is presented in this article, based on a tabu search technique with a specific neighborhood definition which employs a block of jobs.
443 citations
322 citations
TL;DR: A definition of the optimal solution of the transportation problem with fuzzy cost coefficients as well as an algorithm determining this solution are proposed.
286 citations
TL;DR: The effective mass approximation is used to study the dependence of energy levels of lens-shaped SAD on size, depth of confining potential, and the magnetic field and relate the electron and hole energy levels to the magneto-optical properties of the SAD.
Abstract: The electronic structure of lens-shaped self-assembled quantum dots is studied as a function of the dot size, the confining potential, and the magnetic field. The parabolic confining potential and its corresponding energy spectrum are shown to be an excellent approximation. The magnetoexciton spectrum is calculated and compared with recent experiments. \textcopyright{} 1996 The American Physical Society.
285 citations
TL;DR: In this paper, the equality in law of a skewed stable variable and a nonlinear transformation of two independent uniform and exponential variables has been proved, which has led to some inaccuracies in the literature.
270 citations
TL;DR: In this paper, the authors rigorously show that the frequency domain response takes, in both nonbiased and biased walks, the only possible Cole-Cole form of relaxation function determined in this model by the Mittag-Leffler distribution.
Abstract: In the framework of the one-dimensional fractal time random walk (FTRW) relaxation model, we rigorously show that the frequency domain response takes, in both nonbiased and biased walks, the only possible Cole-Cole form. The underlying reason for this is the specific form of the relaxation function (the survival probability of a relaxing system) determined in this model by the Mittag-Leffler distribution. We provide also analytical formulas for the propagators of the nonbiased and biased FTRWs.
126 citations
TL;DR: The problem of scheduling n jobs on a single machine is studied and the problem is shown to be solvable in O(n log n) time if the resource is continuously divisible.
109 citations
TL;DR: The few-electron states of the lens-shaped self-assembled quantum dots in the magnetic field are studied and new features are predicted to occur at higher magnetic fields.
Abstract: The few-electron states of the lens-shaped self-assembled quantum dots in the magnetic field are studied. The calculated charging and infrared absorption spectra reflect the magnetic-field-induced transitions between different states of interacting electrons. The theoretical results compare well with recent experiments by Drexler et al. [Phys. Rev. Lett. 73, 2252 (1994)]. New features are predicted to occur at higher magnetic fields. \textcopyright{} 1996 The American Physical Society.
95 citations
TL;DR: In the paper a new heuristic algorithm is proposed solving the linear ordering problem using the sorting through insertion pattern as well as of the operation of permutation reversal, which seems to be the result of a unique property of the problem.
Abstract: The linear ordering problem is an NP-hard combinatorial problem with a large number of applications. Contrary to another very popular problem from the same category, the traveling salesman problem, relatively little space in the literature has been devoted to the linear ordering problem so far. This is particularly true for the question of developing good heuristic algorithms solving this problem. In the paper we propose a new heuristic algorithm solving the linear ordering problem. In this algorithm we made use of the sorting through insertion pattern as well as of the operation of permutation reversal. The surprisingly positive effect of the reversal operation, justified in part theoretically and confirmed in computational examples, seems to be the result of a unique property of the problem, called in the paper the symmetry of the linear ordering problem. This property consists in the fact that if a given permutation is an optimal solution of the problem with the criterion function being maximized, then the reversed permutation is a solution of the problem with the same criterion function being minimized.
85 citations
09 Feb 1996
TL;DR: Some of the techniques for creating fringe pattern images were presented along with methods of analysis and possible applications of interferometric methods, especially in the field of experimental orthopedics, endoscopy and ophthalmology will be pointed out.
Abstract: Optical metrology based on the principle of interference can be applied as a testing tool in biomedical research. Interferograms in form of fringe patterns can be produced in two-beams interferometers, holographic or speckle interferometers, in setups realizing moire techniques or in deflectometers. By analyzing of the fringe pattern images, information about the shape or mechanical behavior of the object under study can be retrieved. Here, some of the techniques for creating fringe pattern images were presented along with methods of analysis. Possible applications of interferometric methods, especially in the field of experimental orthopedics, endoscopy and ophthalmology will be pointed out.
TL;DR: In this article, the authors showed that basic 2-and 4-pyridylmethyl derivatives of aminophosphonic acids and their esters, as well as the derivatives possessing similar structure, can be converted to amine derivatives with no cleavage of CP bond.
TL;DR: The physical and chemical properties of 8 samples of amber from different localities in Poland (Baltic Coast, Belchatow Tertiary brown coal, and Jaroszow clay mine) were investigated by N 2 sorption at 77 K, positron annihilation spectroscopy for chemical analysis (PASCA) and by organic geochemical methods (FT-IR, 1 H and 13 C NMR, GC, and GC-MS) as mentioned in this paper.
TL;DR: In this article, the authors present experimental results of research on the electrostatic, non-contact measurement of the mass flow rate and mean flow velocity of solids in pneumatic transport lines.
TL;DR: In this article, the enantiomerically pure (Rp)-tert-butylphenylphosphinothioic acid and quinine were successfully used for the direct determination of the Enantiomeric purity of diethyl 1-hydroxyalkyl phosphonates.
Abstract: Enantiomerically pure (Rp)-tert-butylphenylphosphinothioic acid and quinine were successfully used for the direct determination of the enantiomeric purity of diethyl 1-hydroxyalkylphosphonates. Only quinine was effective as a chiral solvating agent for the determination of the enantiomeric excess of diethyl 2-hydroxyalkylphosphonates. Copyright (C) 1996 Elsevier Science Ltd
TL;DR: In this article, the authors reported the results of dynamic phase grating formation in an anthraquinone derivative dichroic dye-doped nematic liquid crystal in which an external DC electric field was used to change the planar alignment of liquid crystal molecules into a near homeotropic one.
Abstract: In this paper we report the results of dynamic phase grating formation in an anthraquinone derivative dichroic dye-doped nematic liquid crystal in which an external DC electric field was used to change the planar alignment of liquid crystal molecules into a near homeotropic one. This field was also needed to produce an efficient grating via photoconductivity-induced molecular reorientation in a degenerate two-wave mixing experiment with He - Ne (632.8 nm) laser light serving as a low power excitation source. The characteristic of the measured effect shows that the mechanism of grating formation is evidently a non-photorefractive one. A diffraction efficiency of up to 20% has been measured in the system. Fast hologram recording and erasing times (1 ms) make this system attractive for image processing applications.
TL;DR: In this article, high-sulfur bituminous coal containing 4.17 wt% of pyritic sulfur and the pyrite concentrate separated from this coal were used to examine the interaction between pyritic sulfates and the organic part of coal during pyrolysis.
TL;DR: In this article, a series of Polish hard coals of different rank that contained sulfur in the quantity from 0.37 to 4.90 wt% was investigated in an atmosphere of the gases evolved during the pyrolysis process.
TL;DR: It was found that some of compounds 4 and 5 are modest cytokine (TNF, IFN) inducers in human peripheral blood leucocyte cultures and block the constitutive endothelial nitric oxide synthase (ce NOS).
Abstract: A convenient synthesis of the 2-carboxyalkyl-1,2-benzisoselenazol-3(2H)-ones 4a–k and their esters 41–p from 2-(chloroseleno)benzoyl chloride (2) and amino acids or their carboxy esters is reported. In similar way other 2-substituted 1,2-benzisoselenazol-3(2H)-ones 4q–u were synthesized. The related bis[2-(carbamoyl)phenyl] diselenides 5 were obtained by reductive conversion of 1,2-benzisoselenazol-3(2H)-ones 4 or directly by the reaction of bis[2-(chlorocarbonyl)phenyl] diselenide (3) with compounds having a primary amino group. It was found that some of compounds 4 and 5 are modest cytokine (TNF, IFN) inducers in human peripheral blood leucocyte cultures and block the constitutive endothelial nitric oxide synthase (ce NOS).
TL;DR: In this article, the effect of interactions of many electrons and holes on optical properties of quantum dots in a magnetic field was studied, showing that the degeneracies in the electronic structure of these artificial atoms lead to a remarkable dependence of the absorption/emission spectrum on density of excitons.
TL;DR: The qualitative agreement with the numerical results gives a remarkable new confirmation of the CF picture.
Abstract: Numerical results for the energy spectra of $N$ electrons on a spherical surface are used as input data to determine the quasiparticle energies and the pairwise "Fermi liquid" interactions of composite fermion (CF) excitations in fractional quantum Hall systems. The quasiparticle energies and their interactions are then used to determine the energy spectra, $E$ vs total angular momentum $L$, of states containing more than two quasiparticles. The qualitative agreement with the numerical results gives a remarkable new confirmation of the CF picture.
TL;DR: In this article, the authors compared the performance of o-, m- and p-cresols in three-component model mixtures with naphthalene and n-hexadecane over a CoMo Al 2 O 3 catalyst at 360°C and a hydrogen pressure of 7 MPa.
TL;DR: In this paper, the use of benzylamine, α-methylbenzenylamine and tritylamine was unsuccessful in the case of dialkyl 1-oxo-alkylphosphonates whereas conversion of 2-oxoxoalkylophosphonate was also achieved although with lower yields.
TL;DR: In this paper, the correlation energy of the LiH molecule has been evaluated in the extended basis set at the experimental geometry of LiH and the results indicate the importance of correlation energy in positron-molecule complexes.
TL;DR: In this paper, the authors deal with a settlement analysis of shallow foundations resting on a layered subsoil, which is based on the finite element method coupled with stochastic versions of the perturbation and the Neumann expansion methods.
TL;DR: A concise presentation of the chemical and crystallographic principles for controlled molecular association into structural building blocks, and their further organisation into three-dimensional crystal structures, is given and several examples are discussed as mentioned in this paper.
TL;DR: In this article, the authors describe the experience obtained with the chips of Al and its alloy with addition of small amount of tungsten powder directly converted into the final product by hot extrusion process.
TL;DR: In this article, a new principal mechanism underlying real-time holographic grating recording in a thin cell filled with a nematic liquid crystal doped with a dye is proposed, where a laser light interference pattern is mapped in the form of a spatial modulation of index of refraction.
Abstract: A new principal mechanism underlying real-time holographic grating recording in a thin cell filled with a nematic liquid crystal doped with a dye is proposed. In the experiment a laser light interference pattern is mapped in the form of a spatial modulation of index of refraction. This is achieved by respective modulation of an electric field in the vicinity of the nematic liquid crystal due to its bulk photoconductivity and subsequent space charge field formation. In the spatially modulated electric field the nematic director is locally reoriented to some degree, leading to the appearance of a phase Δπ grating due to the birefringent properties of a nematic. The externally applied electric field plays an important role in the whole process: it changes the initial planar alignment of liquid crystal molecules and enhances the photogeneration quantum yield. The role of electrical edge conditions in the cell is pointed out as they determine the field distribution in the liquid crystal, which is generally different from the space charge field distribution described for photorefractive materials.
TL;DR: In this paper, a theoretical and experimental analysis of thermal stress effects on the modal polarization properties of highly elliptical-core fibers is presented, based on solving the vectorial Maxwell's equations, using a finite-element scheme.
Abstract: A theoretical and experimental analysis of thermal stress effects on the modal polarization properties of highly elliptical-core fibers is presented. The theoretical analysis is based on solving the vectorial Maxwell's equations, using a finite-element scheme, when form-induced and stress-induced effects are introduced simultaneously through appropriate calculation of the refractive indexes of the anisotropic media. The experimental analysis is done by studying the temperature response of a white-light interferometric sensor employing highly elliptical-core fibers. The calculated temperature sensitivities of the modal birefringence and the polarization mode dispersion in highly elliptical-core fiber are in close agreement with the experimental results. Interpretation of the results useful for designing white-light interferometric sensors composed of highly elliptical-core fibers is also given.
TL;DR: In this article, it was shown that during acidic hydrolysis of 2-and 4-pyridylmethylaminophosphonates, a rearrangement occurred, combined with a cleavage of C-P bond in the phosphonate molecules and subsequent formation of the corresponding amines.
Abstract: The benzylic amines (benzylamine, benzhydrylamine and benzyl carbamate) were applied in the synthesis of aminophosphonates derived from pyridine, pyrrole and imidazole. The Schiff bases obtained from corresponding heterocyclic aldehydes and benzylic amines were caused to react with diphenyl phosphonate or dibenzyl phosphonate to form corresponding heterocyclic aminophosphonates in good yields. The N-(benzylamino)-phosphonates were deblocked by catalytic hydrogenolysis. The benzhydryl group from the phosphonates was removed by acidic hydrolysis, and the carbobenzyloxy group from the phosphonates can be easy removed by treatment with a solution of 30% HBr in acetic acid, as well. It was found that during acidic hydrolysis of 2- and 4-pyridylmethylaminophosphonates a rearrangement occurred. combined with a cleavage of C—P bond in the phosphonate molecules and subsequent formation of the corresponding amines.