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861.
The main focus of this note is on the interval Shapley value for interval games introduced by Alparslan Gök et al. (Cent. Eur. J. Oper. Res. 18:131–140, 2010). In the framework of interval games, we introduce the potential approach and prove that the interval Shapley value can be formulated as the vector of marginal contributions of a potential function. 相似文献
862.
863.
Conventional two-stage data envelopment analysis (DEA) models measure the overall performance of a production system composed of two stages (processes) in a specified period of time, where variations in different periods are ignored. This paper takes the operations of individual periods into account to develop a multi-period two-stage DEA model, which is able to measure the overall and period efficiencies at the same time, with the former expressed as a weighted average of the latter. Since the efficiency of a two-stage system in a period is the product of the two process efficiencies, the overall efficiency of a decision making unit (DMU) in the specified period of time can be decomposed into the process efficiency of each period. Based on this decomposition, the sources of inefficiency in a DMU can be identified. The efficiencies measured from the model can also be used to calculate a common-weight global Malmquist productivity index (MPI) between two periods, in that the overall MPI is the product of the two process MPIs. The non-life insurance industry in Taiwan is used to verify the proposed model, and to explain why some companies performed unsatisfactorily in the specified period of time. 相似文献
864.
This paper studies a problem of scheduling fabrication and assembly operations in a two-machine flowshop, subject to the same predetermined job sequence on each machine. In the manufacturing setting, there are n products, each of which consists of two components: a common component and a unique component which are fabricated on machine 1 and then assembled on machine 2. Common components of all products are processed in batches preceded by a constant setup time. The manufacturing process related to each single product is called a job. We address four regular performance measures: the total job completion time, the maximum job lateness, the total job tardiness, and the number of tardy jobs. Several optimality properties are presented. Based upon the concept of critical path and block schedule, a generic dynamic programming algorithm is developed to find an optimal schedule in O(n 7) time. 相似文献
865.
We study the fractional Schrödinger equations in R1+d, d?3, of order d/(d−1)<α<2. Under the angular regularity assumption we prove linear and nonlinear profile decompositions which extend the previous results [9] to data without radial assumption. As applications we show blowup phenomena of solutions to mass-critical fractional Hartree equations. 相似文献
866.
Taraxacum, known as dandelion, is a large genus of plants in the family Asteraceae. Pharmacological studies have shown that these plants display a wide variety of medicinal properties because Taraxacum extracts contain many pharmacologically active metabolites that display anti-inflammatory, antinociceptive, antioxidant, and anticancer activity. Each plant species displays several different natural constituents, the majority of which have not been studied as no global metabolite screen of the diverse Taraxacum species has been performed. In this study, we investigated the metabolite difference in three species of Taraxacum (T. coreanum, T. officinale, and T. platycarpum) by (1)H NMR spectroscopy and gas chromatography-mass spectrometry (GC-MS) coupled with multivariate statistical analyses. The aim of this study was to identify the different chemical compositions of the polar and nonpolar extracts in these species. A partial least-squares discriminant analysis showed a significantly higher separation among nonpolar extracts (mainly fatty acids and sterols) compared to polar extracts (mainly amino acids, organic acids, and sugars) between these species. A one-way ANOVA was performed to statistically certify the metabolite differences of these nonpolar extracts. Taken together, these data suggest that a metabolomic approach using combined (1)H NMR and GC-MS analysis is an effective analytical method to differentiate biochemical compositions among different species in plants. 相似文献
867.
Kao SY Chang YC Su JH Lu MC Chen YH Sheu JH Wen ZH Wang WH Kuo YH Hwang TL Sung PJ 《Chemical & pharmaceutical bulletin》2011,59(8):1048-1050
(-)-Hydroxylindestrenolide (1), an enantiomer of the known sesquiterpenoid, (+)-hydroxylindestrenolide (2), was isolated from a gorgonian coral identified as Menella sp. The structure, including the relative stereochemistry of 1 was established by spectroscopic methods and by comparison the spectral and physical data with those of 2. Sesquiterpenoid 1 exhibited marginal cytotoxicity toward HL-60 and K562 leukemia tumor cells, and displayed a weak inhibitory effect on superoxide anion generation at a concentration of 10 μg/ml by human neutrophils. 相似文献
868.
Chen YH Tai CY Kuo YH Kao CY Li JJ Hwang TL Fang LS Wang WH Sheu JH Sung PJ 《Chemical & pharmaceutical bulletin》2011,59(3):353-358
Five new eunicellin-type diterpenoids, cladieunicellins A-E (1-5), were isolated from an Indonesian soft coral identified as Cladiella sp. The structures of diterpenoids 1-5 were established using spectroscopic methods. Eunicellins 2 and 5 were found to be cytotoxic against DLD-1 and HL-60 tumor cells, respectively, and 3 displayed inhibitory effects against superoxide anion generation by human neutrophils. 相似文献
869.
SeYeon Hwang YoonKook Park Kyungmoon Park 《The Journal of chemical thermodynamics》2011,43(3):339-343
The high-pressure phase behaviour of the binary system {1-ethyl-methylimidazolium tetrafluoroborate ([EMIM][BF4]) + CO2} was determined over the temperature range of (293.2 to 323.2) K at intervals of 5.0 K with the CO2 mole fraction ranging from 0.153 to 0.578 by using a high-pressure variable-volume view cell. Further, the (vapour + liquid) equilibrium of the binary system {1-hexyl-methylimidazolium tetrafluoroborate ([HMIM][BF4]) + CO2} was measured over the temperature range of (303.2 to 328.2) K with the CO2 mole fraction ranging from 0.314 to 0.593. The Peng–Robinson equation of state along with two-parameter mixing rules has been employed to correlate the experimental results. In case of the ([EMIM][BF4] + CO2) system, the (vapour + liquid + liquid) equilibrium and (vapour + liquid) equilibrium have been observed at a high CO2 mole fraction. The experimental values obtained in this study were compared with the available phase behaviour data of the binary system (1-alkyl-3-methylimidazolium tetrafluoroborate + CO2) in order to investigate the effect of the alkyl chain length in the imidazolium cation on the phase behaviour of such systems. 相似文献
870.
In this study, a photo-alignment material PM4Ch, poly(4-methacryloyloxychalcone), was synthesized. The electro-optical characteristics of a photo-aligned twisted nematic liquid crystal display (TN-LCD), with linearly polarized UV exposure at normal direction on a PM4Ch surface, were investigated. The NLC alignment was uniform. Excellent voltage-transmittance characteristics were obtained; a fast response time was also achieved. Reduction of d.c. voltage decreases with increasing UV exposure time. 相似文献