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91.
A cold atomic medium(Rydberg medium) with cascade configuration under the blockade mechanism is considered. A partial coherent light(PCL) beam is incident on the medium, which makes an angle θ with z-axis. We study the influence of PCL field on the transmission spectrum and find high transmission of probe field for PCL field.Conversely, it is investigated that the transparency of probe field decrease for coherent light field. The transmission of probe field is also studied via beam width of PCL field and investigated high transmission of probe field for small beam width and vice versa. Interestingly, the Goos-H?nchen shift(GHS) in the transmitted light(TL) is studied for PCL field. Large negative and positive GHS in the TL are investigated for PCL field and small beam width of PCL field. 相似文献
92.
In this paper, an Economic Production Quantity (EPQ) model is developed with flexibility and reliability consideration of
production process in an imprecise and uncertain mixed environment. The model has incorporated fuzzy random demand, an imprecise
production preparation time and shortage. Here, the setup cost and the reliability of the production process along with the
backorder replenishment time and production run period are the decision variables. Due to fuzzy-randomness of the demand,
expected average demand is a fuzzy quantity and also imprecise preparation time is represented by fuzzy number. Therefore,
both are first transformed to a corresponding interval number and then using the interval arithmetic, the single objective
function for expected profit over the time cycle is changed to respective multi-objective functions. Due to highly nonlinearity
of the expected profit functions it is optimized using a multi-objective genetic algorithm (MOGA). The associated profit maximization
problem is illustrated by numerical examples and also its sensitivity analysis is carried out. 相似文献
93.
A metastable lattice gas with nearest-neighbor interactions and continuous-time dynamics is studied using a generalized Becker-D?ring approach in the multidimensional space of cluster configurations. The preexponential of the metastable-state lifetime (inverse of nucleation rate) is found to exhibit distinct peaks at integer values of the inverse supersaturation. Peaks are unobservable (infinitely narrow) in the strict limit T-->0, but become detectable and eventually dominate at higher temperatures. 相似文献
94.
95.
Nita H. Shah 《Journal of Mathematical Modelling and Algorithms》2011,10(3):293-305
In this paper, an integrated inventory model for a supply chain comprising of single buyer and single supplier is studied
when demand is stock-dependent and units in inventory deteriorate at a constant rate. The total cost of the integrated system
consists of the transportation cost, inspection cost and the cost of less flexibility under the assumption of JIT deliveries.
The total integrated cost of single-supplier and single-buyer is minimized with respect to number of inspections and deliveries,
the cycle time of deliveries and the delivery size for the replenishment time. A numerical example is given to validate the
model. The sensitivity analysis carried out suggests that the unit inspection cost, deterioration rate of units in inventory
and stock-dependent parameter are the critical factors. 相似文献
96.
Nita Salina Abu Bakar Zal U’yun Wan Mahmood Ahmad Saat 《Journal of Radioanalytical and Nuclear Chemistry》2013,295(1):315-323
In the present study, the depositions of 210Po were assessed in the surface soil and some mosses species found in the area around coal fired power plant using radiochemical deposition and alpha spectrometry counting system. The purposes of the study were to determine activity concentrations of 210Po in mosses and surface soil collected around coal-fired power plant in relation to trace the potential source of 210Po and to identify most suitable moss species as a bio-indicator for 210Po deposition. In this study, different species of mosses, Orthodontium imfractum, Campylopus serratus and Leucobryum aduncum were collected in May 2011 at the area around 15 km radius from Tanjung Bin coal-fired power plant located in Pontian, Johor. The 210Po activity concentrations in mosses and soil varied in the range 102 ± 4 to 174 ± 8 Bq/kg dry wt. and 37 ± 2 to 184 ± 8 Bq/kg dry wt., respectively. Corresponding highest activity concentration of 210Po observed in L. aduncum, therefore, this finding can be concluded this species was the most suitable as a bio-indicator for 210Po deposition. On the other hand, it is clear the accumulation of 210Po in mosses might be supplied from various sources of atmospheric deposition such as coal-fired power plant operation, industrial, plantation, agriculture and fertilizer activities, burned fuel fossil and forest; and other potential sources. Meanwhile, the main source of 210Po in surface soil is supplied from the in situ deposition of radon decay and its daughters in the soil itself. 相似文献
97.
Nistor MT Chiriac AP Vasile C Verestiuc L Nita LE 《Colloids and surfaces. B, Biointerfaces》2011,87(2):382-390
The study presents the preparation of a semi-synthetic hydrogel based on poly(N-isopropyl acrylamide-co-diethylene glycol diacrylate) inserted onto the collagen porous membrane. The synthesis of the hydrogels was performed through radical copolymerization of N-isopropyl acrylamide (NIPAM) with diethylene glycol diacrylate (DEGDA) also as crosslinking agent, using ammonium persulfate as initiator and N,N,N',N'-tetramethylethylene diamine as activator, and it was achieved in the presence of the collagen matrix. The prepared hydrogels were characterized by Attenuated Total Reflectance-Fourier Transform Infrared Spectroscopy and Scanning Electron Microscopy. The swelling behaviour of the semi-interpenetrated polymer network related on the hydrogel composition, it was also evaluated. The pore sizes of the synthesized hydrogels, much larger than the typical mesh size of a conventional hydrogel, allow to consider the hybrid hydrogel based on the inserted poly(NIPAM-co-DEGDA) onto collagen fibrils as a super-porous hydrogel. 相似文献