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At metro junction stations located in transportation hubs, a great number of passengers need to transfer to the metro system from other transportation modes during peak hours. This paper proposes a new train operation strategy—reserving carriages dynamically on each service train at the departure station for the metro junction station, which aims to relieve the serious passenger accumulation at the target station. We construct a nonlinear integer programming model which determines the number of reserved carriages on each train, and the total risk levels of passenger accumulation and passenger waiting time are both taken into account in the objective function. Furthermore, the latest arrival time of passengers on board is introduced to calculate effective passenger loading times analytically. At last, a set of numerical experiments from Beijing Metro Line 4 are implemented to verify the performance and effectiveness of the proposed approach. [ABSTRACT FROM AUTHOR]

In view of the problem that the high content of stone powder in manufactured sand and the change of applied environment will lead to the significant decline of the workability of concrete, in this paper, the change law of the fluidity of cement paste, its correlation with the ambient temperature, and the competitive adsorption performance of stone powder and cement on poly-carboxylate superplasticizer(PCE) were studied under the condition of equal substitution of stone powder. Meanwhile, the mechanism of competitive adsorption was revealed. The results show that the fluidity of cement paste replaced by 20% stone powder decreases by 5.3% and 24.3% respectively at 20 °C and 40 °C, compared with pure cement paste, the influence of temperature on the fluidity is significant. The results of adsorption amount show that when the solid content of PCE is 0.3%, the adsorption amount of PCE on cement particles reaches saturation, and the saturated adsorption amount is 0.41 mg/g, the adsorption amount of PCE on stone powder is 0.58 mg/g, and continues to increase with the increase of PCE content. The results show that the adsorption capacity of PCE on stone powder is stronger than that of cement particles and the increase of ambient temperature will accelerate the adsorption of PCE on the surface of cement particles and stone powder. [ABSTRACT FROM AUTHOR]

The aim of the present study is to reveal the causal effects of Smart City policies on urban innovation. Using the panel data harvested from 103 cities in China, the constructed sample was analysed rigorously based on the combination of the strength of Propensity Score Matching (PSM) and Difference-in-Differences (DID). As suggested by the empirical results, Smart City policies indeed positively and significantly impact urban innovation. Besides, whether policy effects vary with the regional location and city scale is explored; the results reveal that the impact is significantly positive only for the megacities as well as cities in central China. [ABSTRACT FROM AUTHOR]

This work studies the fabrication and pressureless sintering of silicon carbide (SiC) refractories. SiC particles were adopted as aggregates, introducing different amounts (20%, 30%, 40%, 50%, and 60%, by mass) of submicron SiC powder, adding resin as the binder and the carbon source, and B4C as the sintering aid. It is found that when the mass ratio of B4C to the submicron SiC powder is 3%, the optimal sintering can be obtained. With the increase of the submicron powder addition, the sintering linear shrinkage increases and the mechanical properties enhance. The optimal sintering temperature is 2 050-2 100 ℃. [ABSTRACT FROM AUTHOR]

AbstractThe shallow straight-link-shaped structure of 2.5D woven composites (2.5D-SSLS-WC) is a novel material with a wide range of promising applications, but the randomness of its internal structure has brought challenges to performance prediction and engineering design. The gap of existing unit-cell models in capturing the internal randomness of the 2.5D-SSLS-WC material limits the accurate prediction of properties and the optimization of engineering design. In this work, the modeling method for random unit-cell model based on Gaussian distribution is proposed for 2.5D-SSLS-WC structure considering random distribution property of weft yarns and extrusion effects between structural surfaces and internal yarns during the molding process, which can more effectively reflect the practical mesoscopic structure of the material, reveal the micro mechanical behavior inside materials and provide theoretical basis for material design and performance optimization. The mechanical property and damage evolution of the proposed model is predicted and analyzed using finite element (FE) analysis and progressive damage method. The maximum errors of equivalent stiffness and strength between prediction and experimental values are 6.7% and 2.3%, respectively. The results show that the proposed model has high prediction accuracy and can reasonably reflect the damage extension and ultimate failure mode of the material during the loading process, which verifies the rationality of the proposed unit-cell modeling strategy. The modeling method proposed in this paper provides a new perspective for the in-depth understanding and description of the microstructure and mechanical behavior of 2.5D-SSLS-WC materials, which is of significant theoretical and engineering value and can be extended to the modeling of other woven composites. [ABSTRACT FROM AUTHOR]

Background: Computerized cognitive remediation therapy (CCRT) is generally effective for the cognitive deficits of schizophrenia. However, there is much uncertainty about what factors mediate or moderate effectiveness and are therefore important to personalize treatment and boost its effects. Method: In total, 311 Chinese inpatients with Diagnostic and Statistical Manual of Mental Disorders-IV schizophrenia were randomized to receive CCRT or Active control for 12 weeks with four to five sessions per week. All participants were assessed at baseline, post-treatment and 3-month follow-up. The outcomes were cognition, clinical symptoms and functional outcomes. Results: There was a significant benefit in the MATRICS Consensus Cognitive Battery (MCCB) total score for CCRT (F1,258 = 5.62; p = 0.02; effect size was 0.27, 95% confidence interval 0.04–0.49). There were no specific moderators of CCRT improvements. However, across both groups, Wisconsin Card Sort Test improvement mediated a positive effect on functional capacity and Digit Span benefit mediated decreases in positive symptoms. In exploratory analyses younger and older participants showed cognitive improvements but on different tests (younger on Symbol Coding Test, while older on the Spatial Span Test). Only the older age group showed MSCEIT benefits at post-treatment. In addition, cognition at baseline negatively correlated with cognitive improvement and those whose MCCB baseline total score was around 31 seem to derive the most benefit. Conclusions: CCRT can improve the cognitive function of patients with schizophrenia. Changes in cognitive outcomes also contributed to improvements in functional outcomes either directly or solely in the context of CCRT. Age and the basic cognitive level of the participants seem to affect the cognitive benefits from CCRT. [ABSTRACT FROM AUTHOR]

With the development of the heat-resistant resin, carbon fiber resin matrix composites can service at high temperature condition. However, there are very few studies about the thermo-mechanical behavior at temperatures of the composites, and the temperature effects on composites are very complex. Open-hole composite structure is one of the typical bearing structures used in engineering widely. In order to capture the thermo-mechanical behaviors of the open-hole laminates, tensile tests and compressive tests of the open-hole T300/BMP316 laminate were conducted over a wider temperature range (from RT to 310 °C). Based on the experimental results, there occurs an inflection point in the curve of strength versus temperature of the open-hole T300/BMP316 laminates, and tensile strength and compressive strength have the similar variation rules when the temperature increases. In the temperature range from RT to 230 °C, both the tensile strength and compressive strength decrease with the rise of temperature. In the temperature range above 230 °C, both the tensile strength and compressive strength increase with temperature. The temperature effect on compressive strength is greater than on tensile strength. Based on the theory of progressive damage and 3D Hashin's failure criteria, a strength prediction method considering temperature effects was developed and was used to describe the mechanical behaviors of open-hole T300/BMP316 laminate. Compared with the experimental results, the maximum error of predicted strengths is <7%, the fractures and the tendency of tensile/compressive strength varied with temperature obtained by simulations and experiments are similar, which illustrated that the strength prediction model considering temperature effects is effective. [ABSTRACT FROM AUTHOR]