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991.
A multi-objective iterated greedy search for flowshop scheduling with makespan and flowtime criteria 总被引:1,自引:0,他引:1
In this paper, we tackle the problem of total flowtime and makespan minimisation in a permutation flowshop. For this, we introduce
a multi-criteria iterated greedy search algorithm. This algorithm iterates over a multicriteria constructive heuristic approach
to yield a set of Pareto-efficient solutions (a posteriori approach). The proposed algorithm is compared against the best-so-far
heuristic for the problem under consideration. The comparison shows the proposal to be very efficient for a wide number of
multicriteria performance measures. Aside, an extensive computational experience is carried out in order to analyse the different
parameters of the algorithm. The analysis shows the algorithm to be robust for most of the considered performance measures. 相似文献
992.
993.
Piedmont Ralph L.; McCrae Robert R.; Riemann Rainer; Angleitner Alois 《Canadian Metallurgical Quarterly》2000,78(3):582
Because of the potential for bias and error in questionnaire responding, many personality inventories include validity scales intended to correct biased scores or identify invalid protocols. The authors evaluated the utility of several types of validity scales in a volunteer sample of 72 men and 106 women who completed the Revised NEO Personality Inventory (NEO-PI-R; P. T. Costa and R. R. McCrae, 1992) and the Multidimensional Personality Questionnaire (MPQ; A. Tellegen, 1978/1982) and were rated by 2 acquaintances on the observer form of the NEO-PI-R. Analyses indicated that the validity indexes lacked utility in this sample. A partial replication (N?=?1,728) also failed to find consistent support for the use of validity scales. The authors illustrate the use of informant ratings in assessing protocol validity and argue that psychological assessors should limit their use of validity scales and seek instead to improve the quality of personality assessments. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
994.
995.
Marc Stadtler Rainer Bromme 《International Journal of Computer-Supported Collaborative Learning》2007,2(2-3):191-210
Drawing on the theory of documents representation (Perfetti et al., Toward a theory of documents representation. In: H. v.
Oostendorp & S. R. Goldman (Eds.), The construction of mental representations during reading. Mahwah, NJ: Erlbaum, 1999), we argue that successfully dealing with multiple documents on the World Wide Web requires readers
to form documents models; that is, to form a representation of contents and sources. We present a study in which we tested the assumption that the use of metacognitive strategies is crucial to the
formation of documents models. A total of 100 participants with little medical knowledge were asked to conduct an Internet
research on a medical topic. Participants were randomly assigned to four experimental groups that received different types
of metacognitive prompts: participants either received evaluation prompts, monitoring prompts, both types of prompts, or no
prompts. A control group took paper-and-pencil notes. Results showed that laypersons receiving evaluation prompts outperformed
controls in terms of knowledge about sources and produced more arguments relating to the source of information when justifying
credibility judgments. However, laypersons receiving evaluation prompts were not better able to indicate the source of information
after Internet research than controls. In addition, laypersons receiving monitoring prompts acquired significantly more knowledge
about facts, and performed slightly better on a comprehension test. It is concluded that the results underline the importance
of metacognition in dealing with multiple documents. 相似文献
996.
Sarmimala Hore Carmen Vetter Rainer Kern Herman Smit Andreas Hinsch 《Solar Energy Materials & Solar Cells》2006,90(9):1176-1188
Thin titaniumdioxide (TiO2) semiconductor layer with different scattering layers was investigated in dye-sensitized solar cells (DSSC). Since the cost of the photoactive dye in the DSSC is relatively high, it is reasonable to assume that the price of the dye could be one of the decisive factors in determining the price of the DSSC modules. Use of a thin layer of nanocrystalline TiO2 would imply reduction in the amount of dye coverage, however, lower amount of dye in the thin films would imply fewer electron generation upon illumination. Thus, it becomes necessary to include a light scattering layer such that the lower photon conversion due to thin layer could be compensated. In the present study up to 80% increase in current density was observed due to inclusion of scattering layers. Reflectance and transmittance measurements were employed in order to study the optical properties of these scattering layers. The scattering layers, which are considered here, are TiO2-Rutile, zirconiumdioxide (ZrO2), and layers consisting of these two in various proportions. With a 4 μm thin titanium dioxide semiconductor layer as photo electrode and an additional light scattering layer (consisting of TiO2-Rutile and ZrO2 in a ratio of 1:3), efficiencies of 6.8% were achieved. 相似文献
997.
Wang Wen-Fu; Wu Shey-Lin; Liou Ying-Ming; Wang An-Li; Pawlak Cornelius Rainer; Ho Ying-Jui 《Canadian Metallurgical Quarterly》2009,123(6):1261
Animal models of Parkinson’s disease with dementia would greatly facilitate research into the underlying causes of this disorder. Here, we showed that bilateral infusion of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) into the substantia nigra pars compacta (SNc) of Wistar rats caused degeneration of nigrostriatal dopaminergic neurons, cell loss in the hippocampal CA1 area, as well as microglial activation and increase of interleukin-2 levels in several brain regions. In addition, increase of anxiety-like behavior and impairment of object recognition were observed in the MPTP-lesioned rats. These findings suggest that neuroinflammation may contribute to MPTP-induced neurodegeneration and behavioral deficits, which is suggested as an animal model of Parkinson’s disease dementia. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
998.
999.
1000.
Hector M. Alvarez Rainer Kalscheuer Alexander Steinbüchel 《European Journal of Lipid Science and Technology》1997,99(7):239-246
Members of the genera Rhodococcus and Nocardia corallina were investigated for their capability to accumulate storage lipids that occur in the cytoplasm during cultivation of the cells under nitrogen-limiting conditions in the absence or presence of various effectors. All bacteria were able to accumulate triacylglycerols (TAG) as main compounds plus minor amounts of diacylglycerols and wax esters. In addition to neutral lipids, R. fascians, R. erythropolis, and R. opacus MR22 accumulated small amounts of polyhydroxybutyrate (PHB), and N. corallina and R. ruber accumulated significant amounts of polyhydroxyalkanoates (PHA) consisting of 3-hydroxybutyrate (3HB) and 3-hydroxyvalerate (3HV) from glucose or valerate. Alloxan or 3-nitropropionate, which are inhibitors of the citric acid cycle, caused a decrease in the content of odd-numbered fatty acids in the TAG accumulated from acetate by R. opacus PD630. Cerulenin, an inhibitor of the fatty acid de novo synthesis, completely inhibited accumulation of TAG from glucose or gluconate but not from hexadecane in all bacteria investigated. In addition, cerulenin caused an increase of the PHA content and resulted in an increase of the relative amounts of 3HB units in the PHA in R. ruber and N. corallina. Acrylic acid, an inhibitor of fatty acid β-oxidation, completely or partially inhibited accumulation of TAG from hexadecane or valerate, respectively, in R. opacus PD630. In R. ruber, acrylic acid completely inhibited accumulations of TAG from valerate; under these conditions the content of PHA increased twofold, and the polyester consisted exclusively of 3HV. PEG-200 (0.2 to 5%, w/v) caused a decrease in the PHA content, but stimulated the incorporation of 3HV units into the PHA in R. ruber. Therefore, the relative amounts and compositions of both storage lipids can be affected by various compounds in these Gram-positive bacteria. 相似文献