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排序方式: 共有1276条查询结果,搜索用时 15 毫秒
1.
We assess the benefits of sharing demand forecast information in a manufacturer–retailer supply chain, consisting of a traditional retail channel and a direct channel. The demand is a linear function of price with a Gaussian primary demand (i.e., zero-price market potential). Both the manufacturer and the retailer set their price based on their forecast of the primary demand. In this setting, we investigate the value of sharing demand forecasts. We analyze the ‘make-to-order’ scenario, in which prices are set before and production takes place after the primary demand is known, and the ‘make-to-stock’ scenario, in which production takes place and prices are set before the primary demand is known. We also compare the supply chain performance with and without the direct channel under some assumptions (production cost is zero, and each demand function has the same slope of price). We find that the direct channel has a negative impact on the retailer’s performance, and, under some conditions, the manufacturer and the whole supply chain are better off. Our research extends and complements prior research that has investigated only the inventory and replenishment-related benefits of information sharing.  相似文献   
2.
Carbon xerogel (CX), a kind of novel carbon material with low-density and continuous nano-porous structure that can be controlled and tailored on nanometer scale, has been prepared through the sol–gel polycondensation of resorcinol (R) with formaldehyde (F) followed by drying at ambient pressure and carbonization in inert atmosphere, and CX–SiO composite has been synthesized by high energy mechanical ball-milling of the obtained CX and commercial SiO at room temperature and atmosphere. The characteristics of CX and CX–SiO as anode material for lithium-ion battery have been systematically investigated on basis of field emission scanning electron microscope (FESEM), X-ray diffraction (XRD), electrochemical and charge–discharge tests. The results showed that, CX–SiO is composed of active carbon, graphite, SiO and dispersed Si crystal while CX consists of active carbon and graphite, CX–SiO has smaller and much more uniform particles than CX. SiO can greatly improve discharge capacity of CX with an acceptable sacrifice of cycling stability, and the charge–discharge capacity of CX–SiO comes mainly from lithium insertion–extraction in Si–SiO in the sample.  相似文献   
3.
A novel cyclic ammonium salt, N,N-dimethylpyrrolidinium tetrafluoroborate (P11-BF4), was successfully synthesized for the first time. The smallest cyclic structure of P11-BF4 induced high solubility and conductivity in PC, which can easier enter the micropores of activated carbon and occupy more surface area during charge/discharge process.  相似文献   
4.
Han  Ningning  Lu  Jian  Li  Shidong 《Numerical Algorithms》2022,90(3):1197-1223
Numerical Algorithms - Iterative algorithms based on thresholding, feedback, and null space tuning (NST+HT+FB) for sparse signal recovery are exceedingly effective and efficient, particularly for...  相似文献   
5.
《Fluid Phase Equilibria》2005,233(2):123-128
Isobaric vapor–liquid equilibria for the binary mixtures of tert-butanol (TBA) + 2-ethyl-1-hexanol and n-butanol (NBA) + 2-ethyl-1-hexanol were experimentally investigated at atmospheric pressure in the temperature range of 353.2–458.2 K. The raw experimental data were correlated using the UNIQUAC and NRTL models and used to estimate the interaction parameters between each pair of components in the systems. The experimental activity coefficients were obtained using the gas chromatographic method and compared with the calculated data obtained from these equilibrium models. The results show that UNIQUAC model gives better correlation than NRTL for these binary systems. The liquid–liquid extraction of TBA from aqueous solution using 2-ethyl-1-hexanol was demonstrated by simulation and the variation of separation factor of TBA at several temperatures was reported.  相似文献   
6.
《Tetrahedron: Asymmetry》2006,17(21):2957-2959
The asymmetric synthesis of tertiary and quaternary stereocentres has been successfully achieved through Cu-catalyzed 1,6-addition of dialkylzinc reagents to 5-(3-aryl-2-propenylidene) Meldrum’s acid derivatives in the presence of a phosphoramidite ligand.  相似文献   
7.
The purpose of this paper is to construct two superimposed optimization methods for solving the mixed equilibrium problem and variational inclusion. We show that the proposed superimposed methods converge strongly to a solution of some optimization problem. Note that our methods do not involve any projection.  相似文献   
8.
为了发现具有良好生物活性的新型先导化合物,在综合多种高活性化合物结构特点的基础上,设计合成了一系列含苯甲酰基乙烯醇结构的2-取代苯甲酰基-5-烷基-环戊酮类化合物.以己二酸二乙酯为原料,经6步反应制得目标产物,其结构经IR,1H NMR,X射线及元素分析或高分辨质谱确证,并对该类化合物合成方法进行了探讨.初步生测结果表明,部分化合物对油菜表现出明显的抑制活性,在100μg/mL浓度下对油菜的抑制率达到60%以上.  相似文献   
9.
Research on Chemical Intermediates - A highly efficient oligomer antimicrobial agent, polyhexamethylene guanidine hydrochloride (PHMGH), is added to mixtures of polyvinylpyrrolidone (PVP)/chitosan...  相似文献   
10.
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