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With the wide application of thermoelastic structures in industries such as the aerospace field, the problem of topology optimization of thermoelastic structures has become a very common and important research topic. It is well known that the thermal environment has a non‐negligible influence on the dynamic performance of structures. However, few people consider the influence of the thermal environment on structural stiffness in thermoelastic dynamic topology optimization. In practical engineering applications, the influence of the environment on the structure performance should be considered to obtain the optimal structure. In this paper, we focus on the problem of dynamic topology optimization considering the effect of non‐uniform temperature fields on structural stiffness. The influence of non‐uniform temperature fields adds on structural stiffness to the topology optimization of thermoelastic dynamic for the first time, thereby comprehensively addressing its effects on structural stiffness in the context of dynamic topology optimization under harmonic vibration and transient load. The proposed method begins by computing the distribution of the non‐uniform temperature field within the structure. Subsequently, thermal stresses in the structure are determined through the application of thermoelastic theory. The geometric stiffness matrix of the structure is then calculated using finite element theory. The dynamic topology optimization model, employing a variable density approach, is established in conjunction with the dynamic compliance design objective. Sensitivity analysis is conducted through the adjoint method, and the design variables are updated utilizing the method of moving asymptotes. Numerical examples are presented to validate the efficacy of the proposed method and obtain the influence of different factors on the optimization results. The results show that the dynamic compliance of the optimized structure increases with increasing heat flux. For the optimization under harmonic vibration, the optimization results obtained by different external excitation frequencies are significantly different. For transient optimization, the study discovers that the optimization present transient effect. [ABSTRACT FROM AUTHOR]

The rapid growth of online marketplaces and the advance of Internet technology have enabled manufacturers to more easily engage in direct selling through their own online stores. However, as any retail channel suffers misplacements, the manufacturer's direct sales channel will also face a critical inventory misplacement problem if it chooses encroachment. Radio-frequency identification (RFID) proven to be the most effective technology to eliminate the inventory misplacement problem. This paper investigates the strategic interaction between manufacturer encroachment and RFID deployment decisions in a supply chain consisting of a manufacturer and a reseller. We find that the manufacturers' encroachment strategies are determined by channels' misplacement rates, RFID deployment decisions and channel competition intensity. Specifically, the retail (direct) channel's misplacement problem encourages (discourages) the manufacturer to encroach; in addition, if only the retail (if it is direct) channel employs RFID, the encroachment cost threshold increases (decreases) with the RFID tag price; moreover, the more intense the channel competition is, the less likely the manufacturer will be to encroach. Further, when encroachment has occurred, channel competition will be a crucial factor in the direct channel's RFID deployment decision, but it will not affect the deployment of RFID in the retail channel. [ABSTRACT FROM AUTHOR]

Based on the finite volume method, a continuum model that coupled enthalpy‐porosity approach is developed herein to investigate the fluid flow, phase transition, and macrosegregation in the solidification process for bloom continuous casting. The optimal parameters of the process of feeding strip technology (FST) are obtained, and the effects of different processes of regular continuous casting, mold electromagnetic stirring (M‐EMS), and FST on the superheat degree and macrosegregation are compared. The results show that the process of FST can not only greatly reduce the superheat degree of liquid steel and improve the macrosegregation in the bloom center, but also effectively avoid the deterioration of negative segregation defects at the edge of bloom, compared with the processes of regular continuous casting and M‐EMS. The best process parameters for the process of FST are as follows: the strip feeding position is 0.12 m far away from the bloom centerline, and the steel strip feeding velocity is 0.20 m s−1. [ABSTRACT FROM AUTHOR]

We investigate RFID adoption strategies under wholesale price and buy-back contracts in a supply chain with one manufacturer and one retailer who faces inventory misplacement and demand forecast error. RFID can alleviate the misplacement problem, and can reduce demand forecast error by shortening order lead time. By a newsvendor model, we characterise the optimal contract terms in the supply chain without and with RFID adoption, respectively. We further analyse how the contract terms depend on RFID-related parameters (e.g. salable rate and demand forecast error). We find that both without and with RFID, the wholesale price contract will lead to the double marginalisation problem, while the buyback contract can coordinate the supply chain. We show that the supply chain adopts RFID if and only if the tagging cost is below a threshold; the threshold is in negative correlation to the demand forecast error. The supply chain is more willing to adopt RFID under the buy-back contract than under the wholesale price contract. RFID adoption can sometimes lessen the double marginalisation problem under the wholesale price contract, improving the supply chain efficiency. A smaller RFID tagging cost or a reduced forecast error do not necessarily lead to higher supply chain efficiency. [ABSTRACT FROM AUTHOR]

If crowdsourcing wants to be developed steadily, the members are required to be involved in mutual trust and common progress with each other in the virtual community. Firstly, by analyzing the members' participation motivation and interest in virtual community, we spot the fraud motivation of participants. Secondly, based on the principle that long-term interests weigh more than short-term gains and the sanctioning mechanism model, and using the game theory method we establish game model of integrity safeguards mechanism and reputation evaluation mechanism respectively which under considering the moral hazard. The purpose is to employ the two mechanisms to constraint unilateral or bilateral fraud and to ensure good trading environment. Thirdly, through the two mechanisms comparative analysis, the study shows that the profits of solver are always greater in integrity safeguard mechanism than in reputation evaluation mechanism when the effort level of solver has been offered. However, the profits of solver are always greater in reputation evaluation mechanism than in integrity safeguard mechanism when the cost of appeals is too high. Finally, given the case analysis of 'zhubajie', we illustrate the effectiveness of the model. [ABSTRACT FROM AUTHOR]

Red soil from Guangxi, China was selected as the background soil, and a porous biomorphic genetic composite of α -Fe 2 O 3 /Fe 3 O 4 /C comprising a bamboo template (PBGC-Fe/C) was used as a passivator to remediate As(Ⅴ) contaminated soils. The performance of PBGC-Fe/C was characterized by Scanning electron microscopy (SEM), X-ray diffraction (XRD), and Fourier-transform infrared spectroscopy (FT-IR). The results showed that PBGC-Fe/C could improve the passivation effect of As(Ⅴ) from the contaminated soils compared with a single passivation material. Under the conditions of a 5% dose addition, 25% water content, and particle size of 100 mesh, the stability rates of PBGC-Fe/C on As(Ⅴ) contaminated soils with different concentrations of 500 mg·kg -1 and 1000 mg·kg -1 could reach 80.95% and 73.49%, respectively. The porous biomorphic genetic composite of bamboo charcoal provided a large number of adsorption sites for As(Ⅴ), and the acidity of the soil was favorable for the remediation of As(Ⅴ) via passivation. Moreover, PBGC-Fe/C could not only adsorb and fix As(Ⅴ), but also promoted the stabilization of As species. Chemical complexation and ion exchange played major roles in this passivation process.

The specific characteristics and mechanism of passivation of Pb in soil were studied using HAP/C composite (PBGC-HAP/C) as passivation, and using proportion of PBGC-HAP/C, particle size and type of passivator, soil moisture content, soil pH value of Pb, and particle size of the material as influencing factors. The results showed that with an increase in dosage of the passivator and passivation time, the passivation effect increases gradually. Reducing the particle size of the passivator is beneficial to improving the passivation effect. pH has a greater impact on passivation, with the passivation effect obviously rising with increased pH, and the passivation rate in an alkaline environment can reach above 99%. An increase in water content is beneficial to the improvement of the passivation effect, but the contribution is not significant. Through comparative analysis of the XPS, XRD, and FT-IR of materials before and after passivation, the results indicated that the passivation of PBGC-HAP/C to Pb is mainly through direct and indirect effects. Direct effects include physical adsorption, chemical complexation, electrostatic interaction, ion exchange, and precipitation; the indirect effect is mainly enhanced by increasing the pH value of the organic matter.