A model for simulation of crowd behaviour in the evacuation from a smoke-filled compartment

The modelling of crowd evacuation from a building has been studied over the past decades. In this study, a numerical model based on cellular automaton is proposed to simulate the human behaviour termed “flow with the stream” in emergency evacuation from a large smoke-filled compartment. In the model, the smoke effect in the context of visibility is considered since visibility range can affect the human behaviour significantly. To simulate the reality that the smoke concentration in a fire compartment is not constant, the proposed model is developed to deal with the scenario in which the visibility range varies in the course of time. An empirical formula is incorporated into the proposed model to estimate the visibility range. The results of numerical tests show that the proposed model can also be used to investigate the effect of the number of guiders through case study.     

The dielectric and leakage current behavior of CoFe2O4-BaTiO3 composite films prepared by combining method of sol-gel and electrophoretic deposition

Composite CoFe₂O₄-BaTiO₃ films were prepared by combining method of sol-gel and electrophoretic deposition. CoFe₂O₄ thick films were prepared by electrophoretic deposition method and then BaTiO₃ precursor solution was spin-coated on these thick films to obtain dense structure. X-ray diffraction indicated that the films consisted of both spinel CoFe₂O₄ and perovskite BaTiO₃ phase. Dielectric properties and leakage current conduction of the films were studied. Leakage current characterization of the films exhibits an Ohmic conduction behavior at lower electric field and space charge limited conduction behavior at higher electric field, respectively.     

船用惯性导航系统姿态测量误差辨识及其补偿方法研究

本文分析了某型号船用惯性导航系统（ＳＩＮＳ）的试验数据，结果表明，ＳＩＮＳ的姿态误差主要来源于水平测姿传感器。据此，本文对该ＳＩＮＳ水平姿态测量误差的辨识及其补偿方法进行了研究，并建立了水平测姿误差的回归数学模型，以提高ＳＩＮＳ姿态精度     

可实现防碰撞通信的新型声表面波温度传感器

针对多声表面波传感器系统中各传感器信息读取时会产生通信碰撞的问题,提出了一种可实现防碰撞通信的新型声表面波温度传感器;通过分析声表面波温度传感器的回波脉冲信号,将沃尔什码作为编码内容实现了多声表面波温度传感器系统中各传感器的正交编码;将传感器对应的匹配信号与系统回波信号进行互相关运算,提取了系统中各传感器的感测温度信息,达到了防碰撞通信的目标;该传感器兼顾编码效率和加工工艺两方面要求,简化感测信息提取的复杂程度;仿真实验验证了上述理论的正确性。     

Palladium- and nickel-catalyzed aminations of aryl imidazolylsulfonates and sulfamates

A nickel complex derived from dppf, along with NaOt-Bu as the base, allowed for challenging aminations of aryl sulfamates. An improved functional group tolerance is observed in novel palladium-catalyzed aminations of imidazolylsulfonates with rac-BINAP as the ligand.     

Bounding Contingent Claim Prices via Hedging Strategy with Coherent Risk Measures

We generalize the notion of arbitrage based on the coherent risk measure, and investigate a mathematical optimization approach for tightening the lower and upper bounds of the price of contingent claims in incomplete markets. Due to the dual representation of coherent risk measures, the lower and upper bounds of price are located by solving a pair of semi-infinite linear optimization problems, which further reduce to linear optimization when conditional value-at-risk (CVaR) is used as risk measure. We also show that the hedging portfolio problem is viewed as a robust optimization problem. Tuning the parameter of the risk measure, we demonstrate by numerical examples that the two bounds approach to each other and converge to a price that is fair in the sense that seller and buyer face the same amount of risk.     

Composition operators from F(p, q, s) spaces to the nth weighted-type spaces on the unit disc

In this note we characterize the boundedness and compactness of the composition operator from the general function space F(p, q, s) to the nth weighted-type space on the unit disk, where the nth weighted-type space has been recently introduced by Stevo Stevi?.     

Naphthodithiophene-2,1,3-benzothiadiazole copolymers for bulk heterojunction solar cells

Two newly synthesized naphthodithiophene-based copolymers, PNB, exhibit a low optical bandgap of ～1.64 eV with which the solar cells fabricated from the blend of PNB and PC(71)BM afforded a power conversion efficiency of 5.3% with external quantum efficiency over 60% in a broad spectral range.     

100～500 GPa 4.2Ni2.45Fe0.35CoW合金的冲击压缩性和物态方程

 用二级轻气炮驱动飞片技术及对称碰撞技术，测量了两相合金4.2Ni2.45Fe0.35CoW（以下简称93W）的雨贡纽线。其压力范围为100~500 GPa。实测的冲击波速度D和粒子速度u可用直线关系式D=4.008+1.277u (km/s)描述。实验结果与用混合物雨贡纽线叠加原理的计算结果符合甚好。文中还给出了由实验数据计算得到的物态方程数据。     

Effect of a rhombohedral phase on lithium intercalation capacity in graphite

Five natural graphites with different rhombohedral phase (3R phase) content have been investigated as anode materials for rechargeable lithium-ion batteries. The reversible capacity varies from 250 mA h/g to 350 mA h/g for the same intercalation conditions depending on the content of the 3R-phase. With increasing rhombohedral phase in the graphite, the intercalation capacity will be high. A peak at about 10 mV in the cyclic voltammograms (CV) of a sample with a large 3R-phase content is caused by lithium ions occupying boundaries between the rhombohedral (3R) phase and the hexagonal (2H) phase and is responsible for a capacity exceeding the theoretical value.