Decentralization versus coordination in competing supply chains under retailers’ extended warranties

This paper studies a two-tier duopoly competing supply chain system consisting of two manufacturers and two exclusive retailers. Both manufacturers produce differentiated products and both retailers provide extended warranties for the products they sell. Two types of channel-structure strategy options are considered: a decentralized structure with a wholesale price contract and a coordinated structure with a sophisticated contract. We first derive the equilibrium outcomes under three possible chain-to-chain competition scenarios. Subsequently, we reveal how manufacturers control their retail channels to gain more supply chain system profit under an interactive environment with supply chain competition and retailers’ extended warranties. We find that pure coordinated channel competition and pure decentralized channel competition may both reach equilibrium. Furthermore, the interaction forces of supply chain competition and extended warranty service significantly impact the characteristics of the equilibria. Finally, we analyze the competing supply chain’s coordination contract design by using the example of a two-part tariff contract, and determine the feasible contract parameter range that results in a win-win solution for supply chain members.

     

Growth and characterization of high-quality GaN nanowires by ammonification technique

GaN nanowires were successfully synthesized at high quality and large yield on Si (1 1 1) substrate through ammoniating Ga₂O₃/BN films deposited by radio frequency (RF) magnetron sputtering system. X-ray diffraction (XRD), Fourier transformed infrared spectra (FTIR) and selected-area electron diffraction (SAED) confirm that the as-synthesized nanowires are of a hexagonal GaN with wurtzite structure. Scanning electron microscopy (SEM) and high-resolution transmission electron microscopy (HRTEM) reveal that the nanowires have a straight and smooth curved structure with extremely uniform diameter of about 60 nm, which is helpful to the application of GaN nanowires. The present results demonstrate that the BN is a very important intermedium in the growth of GaN nanowires by this method.     

On Strong Kadison–Singer Algebras

We show that many Kadison–Singer algebras are maximal triangular in all algebras containing them although their definition requires the maximality taken in the class of reflexive algebras. Diagonal-trivial maximal non self-adjoint subalgebras of matrix algebras with lower dimensions are classified.     

一类非线性积分偏微分方程的初值问题

讨论初值问题 整体经典解的存在性。该问题来源于粘弹性力学。在关于已知函数的一些正则性假设和p'(s)≥c₁>0,|q'(s)|≤const,λ(0)<0,λ'(0)<λ2(0)的条件下,通过能量估计,证明了该问题整体经典解的存在性。     

不同加载速率下铝自由面微粒子喷射现象研究

 本文主要研究铝自由面微粒子喷射量随压力加载速率的关系，重点是对微射流机制的研究。用人工楔形槽作为自由面上的模拟几何缺陷，用斜波发生器技术改变加载速度，用石英传感器技术测量微粒子喷射量。研究结果表明：在楔形槽尺寸和峰值应力不变的条件下，微粒子喷射量及其最大喷射速度，均随加载速度（加载波阵面宽度的一种度量）的减小而减小；在压力加载条件不变时，发现微粒子喷射量有随几何缺陷体积的增加而增大的迹象。用HELP编码对本实验进行的二维数值模拟结果表明，在数值上与实测数据基本符合。     

Experimental realization of quantum cryptography communication in free space

Quantum cryptography is a new secure communication protocol with the combina- tion of quantum mechanics and information theory[1]. Its security depends on the laws of physics and has been proved strictly[2,3]. Quantum communication is the art of generat- ing and transmitting the keys through a quantum channel between two parties, usually called Alice and Bob. Unlike the classical key distribution, the quantum keys are gener- ated in the process of transmission instantaneously. The keys can be…     

Proca Effect in Reissner–Nordstrom de Sitter Metric

Reissner–Nordstrom de Sitter spacetime with photon rest mass is studied. An iteration method is used to get the metric of this spacetime. In the case of μ → 0, the solution will return to the common Reissner–Nordstrom de Sitter spacetime.     

Measurement of the absolute branching fraction of D+→K0e+ve via K0→π0π0

By analyzing 2.93 fb^-1 data collected at the center-of-mass energy √s=3.773 GeV with the BESIII detector, we measure the absolute branching fraction of the semileptonic decay D⁺→K⁰e⁺v_e to be B(D⁺→K⁰e⁺v_e)=(8.59±0.14±0.21)% using K⁰→K_S⁰→π⁰π⁰, where the first uncertainty is statistical and the second systematic. Our result is consistent with previous measurements within uncertainties..     

Ignition and volatile combustion behaviors of a single lignite particle in a fluidized bed under O2/H2O condition

O₂/H₂O combustion, as a new evolution of oxy-fuel combustion, has gradually gained more attention recently for carbon capture in a coal-fired power plant. The physical and chemical properties of steam e.g. reactivity, thermal capacity, diffusivity, can affect the coal combustion process. In this work, the ignition and volatile combustion characteristics of a single lignite particle were first investigated in a fluidized bed combustor under O₂/H₂O atmosphere. The flame and particle temperatures were measured by a calibrated two-color pyrometry and pre-buried thermocouple, respectively. Results indicated that the volatile flame became smaller and brighter as the oxygen concentration increased. The ignition delay time of particle in dense phase was shorter than that in dilute phase due to its higher heat transfer coefficient. Also, the volatile flame was completely separated from particles (defined as off-flame) in dense phase while the flame lay on the particle surface (defined as on-flame) in dilute phase. The self-heating of fuel particles by on-flame in dilute phase was more obvious than that in dense phase, leading to earlier char combustion. At low oxygen concentration, the flame in the H₂O atmosphere was darker than that in the N₂ atmosphere because the heat capacity of H₂O is higher than that of N₂. With the increase of oxygen concentration, the flame temperature in the O₂/H₂O atmosphere was dramatically enhanced rather than that in the O₂/N₂ atmosphere, where the diffusion rate of oxygen in O₂/N₂ atmosphere became the dominant factor.     

Theoretical study of optical and electronic properties of the bis‐dipolar diphenylamino‐endcapped oligoarylfluorenes as promising light emitting materials

We present a detailed study of the structural, electronic, and optical properties of the bis‐dipolar emissive oligoarylfluorenes, OF(2)Ar‐NPhs. The aim of our quantum‐chemical calculations is to investigate the role of the transition and the influence of the optical properties of the various central aryl cores in the oligoarylfluorenes. Geometry optimizations were performed for the ground‐state and for the first electronically excited‐state. The absorption and emission spectra were calculated using time‐dependent density functional theory (TD‐DFT). The results show that the HOMO, LUMO, energy gap, ionization potentials (IP), electron affinities (EA) and reorganization energy (λ) of the oligoarylfluorenes are significantly affected by the electronic withdrawing property and the conjugated length of the central aryl core. Consistently, the stronger the electron withdrawing strength, the lower the LUMO energy is. This thus improves the electron‐accepting and transporting properties by the low LUMO energy levels. The absorption and emission spectra of this series of bis‐dipolar molecules exhibit red shifts to some extent by the electronic nature of the electron affinitive central core in the oligoarylfluorenes. All the calculated results show that the oligoarylfluorenes are promising as useful light emitting materials for OLEDs. Copyright © 2007 John Wiley & Sons, Ltd.