考虑低碳偏好及碳减排的闭环供应链回收及专利授权策略

研究考虑消费者低碳偏好的闭环供应链回收、碳减排与专利授权决策问题。分别构建制造商回收再制造、零售商回收再制造支付固定专利费、零售商回收再制造支付单位专利费的闭环供应链模型,分析低碳消费者比例、普通消费者对再制品的接受程度及碳权交易价格,对企业回收、碳减排及定价决策的影响,并比较了三种模式下企业及供应链的利润。研究表明:随着市场中低碳消费者比例及普通消费者对再制品接受程度的提高,总会使得回收率及碳减排率增加;碳权交易价格的提高,也会促使制造商提高碳减排率;对制造商来说,其利润在零售商回收再制造且支付固定专利费用下实现最优。从自身利润最优的角度出发,作为领导者的制造商将总是选择零售商回收再制造且支付固定专利费用模式。     

产能约束下的闭环供应链制造商合作策略研究

构建了一个由制造商、回收商和零售商组成的闭环供应链模型,运用Stackelberg博弈对产能约束下制造商的合作策略进行了研究。研究发现:制造商始终有与回收商或零售商合作的经济动机,且当产能较小时,更倾向于与零售商合作;反之,则更倾向与回收商进行合作。此外,相对于无合作模式,不同合作策略对于回收率、供应链整体利润、新产品与再制品总体环境影响程度以及消费者剩余的影响会随着制造商产能大小的变化发生改变,而不同合作策略对于总体环境影响程度的影响与制造商的再制造水平也存在关联。     

Parameter choice by discrepancy principles for ill-posed problems leading to optimal convergence rates

Schock (Ref. 1) considered a general a posteriori parameter choice strategy for the Tikhonov regularization of the ill-posed operator equationTx=y which provides nearly the optimal rate of convergence if the minimal-norm least-squares solution belongs to the range of the operator (T ^* T) ^v , o<v1. Recently, Nair (Ref. 2) improved the result of Schock and also provided the optimal rate ifv=1. In this note, we further improve the result and show in particular that the optimal rate can be achieved for 1/2v1.The final version of this work was written while M. T. Nair was a Visiting Fellow at the Centre for Mathematics and Its Applications, Australian National University, Canberra, Australia. The work of S. George was supported by a Senior Research Fellowship from CSIR, India.     

Thermal decomposition of transition metal carboxylates

Thermal solid-phase decomposition of anhydrous copper(ii) formate has been studied at 120–180 ° The rate of gas evolution during the decomposition depends on the depth of conversion and can be presented as the sum of first-order reaction rates and the rate of the autocatalytic process (a second-order reaction). The evolution of the solid phase during thermolysis has been observed by optical microscopy. The decomposition of copper formate is a complex topochemical process, a combination of homogeneous and heterogeneous transformations and dispersion of large crystals.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. l, pp. 72–76, January, 1996.     

Optimal life strategies in organisms exposed to recurrent critical events

The optimal partition of energy between survival and reproduction is considered for a population subject to recurrent and potentially lethal critical events. The best strategy is found by maximizing fitness, a functional derived from the Lotka equation. The dynamics is governed by a second-order, age-varying, nonlinear system. The energy storage and the probability of survival are the state variables, while the amounts of energy placed into and withdrawn from the storage are the controls. The optimal life strategy is shown to be as follows: build up the storage at the very beginning of life, and then progressively deplete it to resist the critical events.This work was partially supported by MURST Project Ricerche sui Fondamenti della Conservazione della Natura. The authors would like to thank C. Ricci for suggesting the problem and C. Matessi for helpful discussion.     

Fubini theorem for anticipating stochastic integrals in Hilbert space

Let (X,l,) be a measure space, letW be a cylindrical Hilbert-Wiener process, and let be an anticipating integrable process-valued function onX. We prove, under natural assumptions on, that there exists a measurable version Y_x,x X, of the anticipating integral of(x) such that the integral _x Y_x(dx) is a version of the anticipating integral of _X (x)(dx). We apply this anticipating Fubini theorem to study solutions of a class of stochastic evolution equations in Hilbert space.     

Cyclical games with prohibitions

We consider a certain combinatorial game on a digraph for two cases of the price function. For one case the game in question extends the cyclical game studied in Ehrenfeucht and Mycielski (1979) and Gurvitch, Karzanov and Khachiyan (1988) which, in its turn, is a generalization of the well-known problem of finding a minimum mean cycle in an edge-weighted digraph. We prove the existence of optimal uniform stationary strategies for both cases and give algorithms to find such strategies.This work was partially supported by Chaire municipale, Mairie de Grenoble.     

Thermal and mechanical-induced phase transformations during YAG and alumina–YAG syntheses

The preparation of pure Y₃Al₅O₁₂ (YAG) and 50 vol% Al₂O₃–YAG composite powders by a wet chemical route is presented. The role of the synthesis temperature during reverse-strike precipitation has been investigated, showing its relevant effect on the purity and homogeneity of YAG powder. The composite material was prepared by comparing two different synthesis routes. A composite powder was synthesized via reverse-strike temperature-controlled co-precipitation. In the latter case, a pure-alumina precursor was firstly reverse-strike precipitated and then doped with an yttrium salt solution. For both syntheses, the role of thermal and mechanical pre-treatments on the phase development was demonstrated.     

Kilogram-scale synthesis of carbon quantum dots for hydrogen evolution,sensing and bioimaging

A facile, low-cost, green, kilogram-scale synthesis of high quality CQDs were synthesized. The throughput of CQDs is 1.4975 kg in one pot and the as-prepared CQDs have a highly crystalline hexagonal structure with remarkable solubility, stability, and biocompatibility. It showed outstanding electrocatalytic activity, Fe³⁺ sensitivity and good biocompatibility.