This paper demonstrates that an important role of intermediaries in supply chains is to reduce the financial risk faced by retailers. It is well known that risk averse retailers when faced by the classical single-period inventory (newsvendor) problem will order less than the expected value maximizing (newsboy) quantity. We show that in such situations a risk neutral distributor can offer a menu of mutually beneficial contracts to the retailers. We show that a menu can be designed to simultaneously: (i) induce every risk averse retailer to select a unique contract from it; (ii) maximize the distributor's expected profit; and (iii) raise the order quantity of the retailers to the expected value maximizing quantity. Thus inefficiency created due to risk aversion on part of the retailers can be avoided. We also investigate the influence of product/market characteristics on the offered menu of contracts. 相似文献
Discovering and designing novel materials is a challenging problem as it often requires searching through a combinatorially large space of potential candidates, typically requiring great amounts of effort, time, expertise, and money. The ability to predict reaction outcomes without performing extensive experiments is, therefore, important. Toward that goal, we report an approach that uses context-free grammar-based representations of molecules in a neural machine translation framework. This involves discovering the transformations from the source sequence (comprising the reactants and agents) to the target sequence (comprising the major product) in the reaction. The grammar ontology-based representation hierarchically incorporates rich molecular-structure information, ensures syntactic validity of predictions, and overcomes over-parameterization in complex machine learning architectures. We achieve an accuracy of 80.1% (86.3% top-2 accuracy) and 99% syntactic validity of predictions on a standard reaction dataset. Moreover, our model is characterized by only a fraction of the number of training parameters used in other similar works in this area. 相似文献
Hexanal is rapidly autoxidized in mixture with nonlipidic substrates even at 25 degrees C. The formation of peroxides follows the kinetics of a first order reaction with respect to hexanal (k1 about 10(-5) min-1), and is higher in mixture with casein or lysine-impregnated cellulose than with cellulose. In mixtures containing pure hexanal, peroxides are decomposed more rapidly after second-order reaction with respect to peroxides (k2 about 10(-3) mmol X kg-1 X min-1) while only slowly by the first-order reaction (k3 about 10(-5) min-1). In presence of small amounts of hexanoic acid the rate of second-order peroxide decomposition remained unaffected while the rate of the first-order peroxide decomposition increased by 4 orders (k3 about 10(-1) min-1). The presence of peroxides was percepted in the odour by sensory analysis contrary to nonvolatile lipid hydroperoxides. 相似文献
A new 11 T SRAM cell with write-assist is proposed to improve operation at low supply voltage.In this technique,a negative bit-line voltage is applied to one of the write bit-lines,while a boosted voltage is applied to the other write bit-line where transmission gate access is used in proposed 11 T cell.Supply voltage to one of the inverters is interrupted to weaken the feedback.Improved write feature is attributed to strengthened write access devices and weakened feedback loop of cell at the same time.Amount of boosting required for write performance improvement is also reduced due to feedback weakening,solving the persistent problem of half-selected cells and reliability reduction of access devices with the other suggested boosted and negative bit-line techniques.The proposed design improves write time by 79%,63% and slower by 52% with respect to LP 10 T,WRE 8 T and 6 Tcells respectively.It is found that write margin for the proposed cell is improved by about 4×,2.4× and 5.37× compared to WRE8 T,LP10 T and 6 T respectively.The proposed cell with boosted negative bit line (BNBL) provides 47%,31%,and 68.4% improvement in write margin with respect to no write-assist,negative bit line (NBL) and boosted bit line (BBL) write-assist respectively.Also,new sensing circuit with replica bit-line is proposed to give a more precise timing of applying boosted voltages for improved results.All simulations are done on TSMC 45 nm CMOS technology. 相似文献
This paper presents a new dual Vt 8T SRAM cell having single bit-line read and write,in addition to Write Assist and Read Isolation (WARI).Also a faster write back scheme is proposed for the half selected cells.A high Vt device is used for interrupting the supply to one of the inverters for weakening the feedback loop for assisted write.The proposed cell provides an improved read static noise margin (RSNM) due to the bit-line isolation during the read.Static noise margins for data read (RSNM),write (WSNM),read delay,write delay,data retention voltage (DRV),leakage and average powers have been calculated.The proposed cell was found to operate properly at a supply voltage as small as 0.41 V.A new write back scheme has been suggested for half-selected cells,which uses a single NMOS access device and provides reduced delay,pulse timing hardware requirements and power consumption.The proposed new WARI 8T cell shows better performance in terms of easier write,improved read noise margin,reduced leakage power,and less delay as compared to the existing schemes that have been available so far.It was also observed that with proper adjustment of the cell ratio the supply voltage can further be reduced to 0.2 V. 相似文献
Supplier selection is one of the key activities of purchase management in supply chain. Supplier selection is a multifaceted problem relating qualitative and quantitative multi-criteria. This paper deals with a supplier selection problem in an Indian automobile company. The work presents selection of headlamp supplier using integrated fuzzy multi-criteria decision-making approaches: analytical hierarchy process (AHP) and technique for order of preference by similarity to ideal solution (TOPSIS). The selection process starts with identifying the criteria based on literature review and interviewing industry experts. Weights to criteria are assigned using AHP, and suppliers are ranked using AHP and TOPSIS. Consistency tests are carried out to check the quality of expert’s inputs. Also, sensitivity analysis is done to check the robustness of the approach. The results address that fuzzy approaches could be effective and more accurate than the existing approaches for supplier selection problems.
The aim of this study is to assess pullulan as a novel steric stabilizer during the wet-stirred media milling (WSMM) of griseofulvin, a model poorly water-soluble drug, and as a film-former in the preparation of strip films via casting–drying the wet-milled drug suspensions for dissolution and bioavailability enhancement. To this end, pullulan films, with xanthan gum (XG) as thickening agent and glycerin as plasticizer, were loaded with griseofulvin nanoparticles prepared by WSMM using pullulan in combination with sodium dodecyl sulfate (SDS) as an ionic stabilizer. The effects of drug loading and milling time on the particle size and suspension stability were investigated, as well as XG concentration and casting thickness on film properties and dissolution rate. The nanosuspensions prepared with pullulan–SDS combination were relatively stable over 7 days; hence, this combination was used for the film preparation. All pullulan-based strip films exhibited excellent content uniformity (most?<3% RSD) despite containing only 0.3–1.3?mg drug, which was ensured by the use of precursor suspensions with?>5000 cP viscosity. USP IV dissolution tests revealed fast/immediate drug release (t80?30?min) from films?<120?μm thick. Thinner films, films with lower XG loading, or smaller drug particles led to faster drug dissolution, while drug loading had no discernible effect. Overall, these results suggest that pullulan may serve as an acceptable stabilizer for media milling in combination with surfactant as well as a fast-dissolving film former for the fast release of poorly water-soluble drug nanoparticles. 相似文献
Thick ceramic coatings deposited by plasma spraying techniques are widely used as wear and corrosion resistant coatings at
high temperature. To measure accurately the thermal diffusivity of such coatings, the diffusivimeter of LNE has been set up
to allow multilayered material studies up to 1,400°C by rear-face and front-face laser flash methods. These two methods have been compared in a large temperature range by measuring the thermal diffusivity
of homogeneous (Armco iron and Poco graphite) and multilayered materials (chromium oxide coating deposited on iron alloy substrate).
The thermal-diffusivity values measured by using front-face and rear-face techniques are in good agreement, with a relative deviation of less than 5% depending on temperature and materials. 相似文献
In this study, Cd1−xZnxSySe1−y (0 ≤ x = y ≤ 0.35) photoelectrodes are deposited via inexpensive facile chemical bath deposition. The effects of Zn and S doping on the compositional, microstructural, electrical, and optical properties of thin films were analysed. The electrochemical photovoltaic (EPV) cell of configuration Cd1−xZnxSySe1−y/0.25M sulfide/polysulfide/C was assembled to examine the different performance parameters in light and in dark conditions. An EPV cell fabricated with the Cd1−xZnxSySe1−y (0 ≤ x = y ≤ 0.075) photoelectrode exhibited a maximum photoconversion efficiency of 3.18%. This performance can be attributed primarily to the enhanced light-absorption ability of the material because of the enhanced rough microstructure and low recombination of photo-injected electrons with the electrolyte. The photovoltaic (PV) performance is significantly enhanced after doping CdSe with Zn and S. 相似文献