Demand forecast sharing in a dual-channel supply chain

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.     

Preparation and characterization of carbon xerogel (CX) and CX–SiO composite as anode material for lithium-ion battery

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.     

Facile cyclic ammonium salt with the smallest size for high performance electric double layer capacitors

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.     

The finite steps of convergence of the fast thresholding algorithms with f-feedbacks in compressed sensing

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...     

Isobaric vapor–liquid phase equilibria for the binary systems of tert-butanol + 2-ethyl-1-hexanol and n-butanol + 2-ethyl-1-hexanol

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.     

Asymmetric Cu-catalyzed 1,6-conjugate addition of dialkylzinc reagents to 5-(3-aryl-2-propenylidene) Meldrum’s acids

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.     

Quantum limited frequency modulation laser spectroscopy

Frequency modulation spectroscopy (FMS) is an optical heterodyne technique which allows high-resolution, high-sensitivity measurements of absorptions or dispersions associated with narrow spectral features. With new methods, the sensitivity limitations of FMS (caused by residual amplitude modulation) can be overcome, and quantum-limited performance can be readily achieved.     

Preparation and Properties of Electrospun Sheath-core Modified-PMMA Nanofibers with Photoluminescence and Photochromic Functions

Multi-functional nanofibers are playing an important role in the optical field, and are widely used in fluorescence indication, product anti-counterfeit identification and smart clothing. Nanofibers with photoluminescence and photochromic functions are already attracting more interest from researchers. In this work, based on electrospun technology, the modified-PMMA nanofibers[PMMA=poly(methyl methacrylate)] with photoluminescence and photochromic functions were prepared through the design of the sheath-core structure(SCNFs 1-4). Compared with other samples, SCNF-4 shows outstanding photoluminescence and photochromic functions. SCNF-4 can produce green light and its fluorescence intensity and fluorescence lifetime can reach 7144 a.u. and 1031.32 μs, respectively. In photochromic functions, SCNF-4 can show purple in 1 min under the 365 nm ultraviolet light, and the color can be preserved for more than 4 h under the sunlight. When SCNF-4 is irradiated by far infrared light, the color of the samples can fade quickly in 40 s. Under the irradiation of ultraviolet light of different wavelengths, SCNF-4 can display multi-color fluorescence and achieve a reversible transition between white and purple. The design of the sheath-core structure realizes the complementarity of photoluminescence and photochromic functions of the electrospun modified-PMMA nanofibers, which is important to promote the wide application of multi-functional nanofibers in the optical field.     

Nearly invariant subspaces for shift semigroups

Let{T (t)}_t≥0 be a C₀-semigroup on an infinite-dimensional separable Hilbert space; a suitable definition of near{T (t)~*}_t≥0 invariance of a subspace is presented in this paper. A series of prototypical examples for minimal nearly{S(t)~*}t≥0 invariant subspaces for the shift semigroup{S(t)}_t≥0 on L²(0,∞) are demonstrated, which have close links with near T~*_θ invariance on Hardy spaces of the unit disk for an inner function θ. Especially, ...