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991.
This paper examines bidding strategies in a bilateral market in which generating companies submit bids to loads. A load accepts electricity delivery from the generator with the lowest bid at its bid price as long as this price is not higher than the load's willingness to pay. Necessary and sufficient conditions of Nash equilibrium (NE) bidding strategy are derived based on a generic generating cost matrix and the loads' willingness to pay vector. The study shows that in any NE, efficient allocation is achieved. Furthermore, all Nash equilibria are revenue equivalent for the generators. Based on the necessary and sufficient conditions, this problem is formulated as an optimal assignment problem. Network optimization techniques are applied to calculate NE bid prices for the generators  相似文献   
992.
To detect faults in a time-dependent process, we apply a discrete wavelet transform (DWT) to several independently replicated data sets generated by that process. The DWT can capture irregular data patterns such as sharp "jumps" better than the Fourier transform and standard statistical procedures without adding much computational complexity. Our wavelet coefficient selection method effectively balances model parsimony against data reconstruction error. The few selected wavelet coefficients serve as the "reduced-size" data set to facilitate an efficient decision-making method in situations with potentially large-volume data sets. We develop a general procedure to detect process faults based on differences between the reduced-size data sets obtained from the nominal (in-control) process and from a new instance of the target process that must be tested for an out-of-control condition. The distribution of the test statistic is constructed first using normal distribution theory and then with a new resampling procedure called "reversed jackknifing" that does not require any restrictive distributional assumptions. A Monte Carlo study demonstrates the effectiveness of these procedures. Our methods successfully detect process faults for quadrupole mass spectrometry samples collected from a rapid thermal chemical vapor deposition process  相似文献   
993.
Coherent heterodyne detection in optical communication is degraded by phase instabilities present when a semiconductor laser is used as a local oscillator. Postdetection processing that accounts for these instabilities is suggested, based on a diffusion-process model for oscillator instabilities and a maximum-likelihood sequence-estimator of information symbols modulating the received light.  相似文献   
994.
The kinetics of drying of slab-like materials in- mersed in a fluidized bed of silica gel particles at a relatively low temperature, 30 °C, is studied. As a re- sult of desiccant particle action large surface-to-bed moisture fluxes and, consequently, large drying rates are attained. For all examined materials (cardboard, veneer, asbestos and ceramic plates) the drying times in the desiccant fluidized bed are much shorter than those in the empty apparatus with the same air flow, temperature and humidity. A simple, diffusional model of the drying based upon a mean mass capacity concept is developed. The drying curves calculated from the model are in good agreement with the experimental ones.  相似文献   
995.
Earlier work on the low temperature solution polyamidation of bisacid A2 has raised a number of structural problems. Work carried out more recently showed that the problem of apparent nonisostoichiometry could be reasonably satisfactorily explained. The present paper reports the synthesis and investigates the properties of a further series of polyamides based upon Bisacid A2. More importantly, however, a detailed characterization and evaluation of the new polymers with respect to their structures is presented. This enabled us to compare the various structures in the light of the experimental evidence provided by a number of analytical and spectroscopic techniques, solution behavior, molecular weight, and thermal, morphological, and mechanical properties. Some work was also done on the effect of incorporating a small amount of a trifunctional monomer into the polyamide system.  相似文献   
996.
The fatty acid compositions of total polar and total neutral lipids of Atlantic herring eggs and larvae were determined immediately before fertilization, after fertilization and at various times during subsequent embryonic and early larval development. Within 3 hr after fertilization the percentage of total PUFA in neutral lipid decreased from 33% to 20%, with a reciprocal increase in monoenes. Thereafter the percentage of PUFA in the neutral lipids increased progressively, attaining the original level in ripe eggs by the time of yolk sac absorption. During the larval stages the percentage of PUFA continued to increase in the neutral lipid, reaching almost 44% of the total by day 32 after fertilization, although it was reduced to 32% by day 36. The percentage of monoenes in the neutral lipid displayed a progressive decrease during the whole period of development from 3 hr after fertilization. Throughout all the developmental periods the fatty acid composition of total polar lipids remained essentially constant. The polar lipids of the yolk sac displayed virtually the same fatty acid composition as the larval bodies, but the neutral lipids of the yolk sac were low in PUFA compared to the larval bodies. The results are discussed with reference to changes in lipid class composition during development. The conservation of high levels of PUFA in lipids during embryogenesis and early larval development reflects the importance of these fatty acids during development.  相似文献   
997.
Distilled fractions of a coal-derived liquid from the H-Coal process were upgraded to diesel fuel by catalytic hydrotreatment. The total hydrotreated products were distilled into naphtha (<180°C) and diesel fuel fractions (>180°C) and the diesel fractions were analysed for hydrocarbon-type composition, hydrogen content and some diesel fuel properties. GC—MS-analyses were carried out on the hydrocarbon-type fractions to identify individual chemical compounds. To investigate the effect of different distillation cut points on diesel fuel yield and properties, cut points for one hydrotreated product were varied. The diesel fuel cetane numbers were correlated with percentage hydrogen, total aromatics and saturates. Cetane numbers above 40 were obtained for diesel fuels containing (i) more than 75% saturates, (ii) less than 15% total aromatics and (iii) a hydrogen content above 12.8%. Compounds identified by GC—MS-analyses (in the diesel fractions) were typical aromatic and cycloparaffin compounds. Normal-and iso-paraffin compounds were not detected. By varying the distillation cut point from 135 to 180°C, the cetane number of the residual diesel fraction improved from 37 to 44. This increase is ascribed to the removal of aromatic compounds in the 135–180°C boiling point range.  相似文献   
998.
999.
1000.
The Grimsel Test Site (Felslabor Grimsel — FLG) is situated at a depth of 450 m in the Juchlistock massif of the Bernese Oberland. It is managed by the National Cooperative for the Storage of Radioactive Waste (NAGRA-Switzerland).By means of a heater test, the power output of canisters filled with high-level waste is simulated. This heater test is performed by the German Gesellschaft für Strahlen- und Umweltforschung — GSF. Two electrical heaters, with a heatable length of 6 m, a diameter of 0.3 m and an available power of 4 kW/m, are installed in two vertical boreholes. One of them is located in the granite adjacent to a strongly fractured lamprophyre vein, the other one directly within this disturbed zone. They are operating since August 1986.The thermo-mechanical reaction of the rock mass is registered by a large number of measurement devices which are installed in an array of instrument boreholes around the heaters. They record the deformation and the alteration of rock stresses, the pore water pressure and the water conductivity caused by heating.  相似文献   
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