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31.
As the service industries grow, tasks are not directly assigned to the skills but the knowledge of the worker which is to be valued more in finding the best match. The problem becomes difficult mainly because the match has to be seen with the objectives of both sides. Assignment methods fail to respond to a multi-objective, multi-constraint problem with complicated match; whereas, metaheuristics is preferable based on computational simplicity. A conditional genetic algorithm is developed in this study to propose both global and composite match using different fitness functions. This algorithm kills the infeasibilities to achieve the maximum number of matches. The proposed algorithm is applied on an academic problem of multi-alternative candidates and multi-alternative tasks (m × n problem) in two stages. In the first stage, four different fitness functions are evaluated and in the second stage using one of the fitness functions global and composite matching have been compared. The achievements will contribute both to the academic and business world. 相似文献
32.
Omer Andac Yildiray Topcu Veysel T. Yilmaz Kutalmis Guven 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(12):1381-1384
The structures of the title triethanolamine (tea) complexes of CdII and HgII saccharinates, bis(triethanolamine)-κ3O,N,O′;κ4O,N,O′,O′′-cadmium(II) 1,2-benzisothiazol-3(2H)-onate 1,1-dioxide, [Cd(C6H15NO3)2](C7H4NO3S)2, (I), and bis(triethanolamine)-κ3O,N,O′;κ4O,N,O′,O′′-mercury(II) 1,2-benzisothiazol-3(2H)-onate 1,1-dioxide, [Hg(C6H15NO3)2](C7H4NO3S)2, (II), or [M(tea)2](sac)2, where M is CdII or HgII and sac is the saccharinate anion, reveal seven-coordinate metal ions in both complexes. Both complex cations, [M(tea)2]2+, adopt a monocapped trigonal prism geometry in which the two tea ligands exhibit different coordination modes to achieve seven-coordination. One tea ligand acts as a tetradentate ligand using all its donor atoms, while the other behaves as a tridentate O,N,O′-donor ligand, with one of its ethanol groups remaining uncoordinated. The H atoms of the free and coordinated hydroxyl groups of the tea ligands are involved in hydrogen bonding with the amine N atom, and with the carbonyl and sulfonyl O atoms of neighbouring sac ions, forming an infinite three-dimensional network. A weak π–π interaction between the phenyl rings of the sac ions also occurs. 相似文献
33.
A novel manganese complex, [Mn(phen)2(H2O)2](sac)2·H2O, was synthesized by the reaction of [Mn(sac)2(H2O)4]·2H2O with 1,10-phenantroline in aqueous solution and characterized by elemental analysis, IR spectral evidence, magnetic measurements, thermal analysis and single crystal X-ray diffraction. The compound crystallizes in triclinic system, space group P-1, with Z=2. The saccharinate ions do not coordinate the central metal, instead are present as the complementary anions. In the complex cation, Mn(II) is coordinated by two phen and two aqua ligands, and exhibits a distorted octahedral coordination with a high-spin configuration. The presence of lattice and coordinate water molecules are also confirmed by thermal analysis and IR spectroscopy. 相似文献
34.
We report true left-handed (LH) behavior in a composite metamaterial consisting of a periodically arranged split ring resonator (SRR) and wire structures. We demonstrate the magnetic resonance of the SRR structure by comparing the transmission spectra of SRRs with those of closed SRRs. We have confirmed experimentally that the effective plasma frequency of the LH material composed of SRRs and wires is lower than the plasma frequency of the wires. A well-defined LH transmission band with a peak value of -1.2 dB (-0.3 dB/cm) was obtained. The experimental results agree extremely well with the theoretical calculations. 相似文献
35.
H.?KockarEmail author M.?Alper H.?Topcu 《The European Physical Journal B - Condensed Matter and Complex Systems》2004,42(4):497-501
The influence of the deposition potentials applied in continuous and pulse
waveforms on the properties of the electrodeposited NiFe alloy films have
been investigated. The films were grown on (100) textured polycrystalline
copper substrates. During growth, the films were characterized by recording
the current-time transients. The composition of samples was determined by
inductively coupled plasma atomic emission spectrometry (ICP-AES). The
analysis results revealed that the Fe content in the films
decreases as both the deposition potential and the film thickness increase.
The X-ray patterns showed that the films have face centred cubic (fcc)
structure as their substrates and the (111) texture. The magnetic
characteristics of films studied by a vibrating sample magnetometer (VSM)
were found to vary depending on the type of the deposition (pulse or
continuous) and the thickness of samples. The easy axis is in the film plane
for all samples. 相似文献
36.
Omer Andac Yildiray Topcu Veysel T. Yilmaz William T.A. Harrison 《Journal of chemical crystallography》2000,30(12):767-771
The crystal structure of trans-bis(monoethanolamine)bis(saccharinato)nickel(II), [Ni(C7H4NO3S)2(C2H7NO)2], has been determined from X-ray diffraction data. The metal complex is monoclinic, with a = 11.0555(5), b = 8.9103(4), c = 11.3890(5) Å, = 105.0230(10)°, Z = 2, and space group P21/c
. The structure consists of individual molecules. Two monoethanolamine molecules and two saccharinate anions coordinate the nickel atom forming a distorted octahedron. The monoethanolamine molecules act as a bidentate ligand and form five-membered trans chelate rings, which constitute the plane of the coordination octahedron, while two saccharinate ions behave as a monodentate ligand occupying the axial positions. Intermolecular hydrogen bonds link the molecules to form a three-dimensional infinite structure. 相似文献
37.
Recep Özen Kutalmis Guven Hatice Can Metin Balci 《Journal of chemical crystallography》2004,34(7):477-481
The title compound 6-phenyl-4,6,8-triazatetracyclo[9.2.1.02,10.04,8]tetradec-2(10)-ene-5,7-dione (6) has been synthesized by the addition of 4-phenyl-1,2,4-triazole-3,5-dione (PTAD) to 2,3-dimethylenebicyclo[2.2.1]heptane. The cell parameters are a = 9.991(5), b = 11.754(9), c = 6.549(5) Å, = 101.08(7)°, = 103.31(5)°, = 98.24(5)°. The crystal structure of 6 was determined. The obtained geometrical parameters were highly correlated with the DFT calculations. The experimentally determined folding angle of the double bond was found to be 8.44°. The effect of the electron-withdrawing ability of nitrogen atom on the degree of pyramidalization is discussed. 相似文献
38.
An inverse theorem of the trigonometric approximation theory in Weighted Orlicz spaces is proved and the constructive characterization
of the generalized Lipschitz classes defined in these spaces is obtained. 相似文献
39.
Zeynep Medine Ozmen Bulent Guven 《International Journal of Mathematical Education in Science & Technology》2019,50(1):25-45
Introductory statistics courses, which are important in preparing students for their daily lives, generally derive inferential statistics from informal knowledge. In this transition process, sampling distributions have an important place, yet research has shown that students often have difficulties with this concept. In order to increase their understanding of sampling distributions, students should have a strong conceptual foundation that is balanced with procedural knowledge. To address this issue, this study was designed to examine the relationship between college students’ procedural and conceptual knowledge of sampling distributions. With this aim in mind, an achievement test consisting of two sections – procedural and conceptual knowledge – was prepared. In answering the questions related to procedural knowledge, the participants were more successful in identifying the relationship between standard deviation of a population and sample means. However, they lacked theoretical knowledge about statements that they had heard or knew intuitively. Simulation activities provided in statistics courses may support students in developing their conceptual understanding in this regard. 相似文献
40.
Guven I. Madenci E. Cho Lik Chan 《Components and Packaging Technologies, IEEE Transactions on》2002,25(4):684-694
Electronic packages experience large temperature excursions during their fabrication and under operational conditions. Inherent to electronic packages are the presence of geometric and material discontinuities. The regions where adhesive bond lines intersect with convective heat-loss surfaces are the most critical locations for failure initiation due to heat flux singularities and extreme thermo-mechanical stresses. Thus, accurate calculation of the flux field, as well as the temperature field, is essential in transient thermo-mechanical stress analysis. Although the finite element method (FEM) is highly efficient and commonly used, its application with conventional elements suffers from poor accuracy in the prediction of the flux field in these regions. The accuracy of the results from the boundary element method (BEM) formulation, which requires computationally intensive time-integration schemes, is much higher than that of the FEM. However, in this study, a novel boundary element-finite element coupling algorithm is developed to investigate transient thermal responses of electronic packages consisting of dissimilar materials. 相似文献