Enhancing optical absorption in visible light of ZnO co-doped with europium and promethium by first-principles study through modified Becke and Johnson potential scheme

By using first-principles calculations we studied the electronic, optical and magnetic properties of ZnO co-doped with Eu and Pm. In this calculation, we used Wien2k code based on full potential linearized augmented plane waves (FP-LAPW) method with the modified Becke-Johnson (mBJ) approximation. This correction gives good band gap compared to experimental band gap. The introduction of Eu and Pm codoping leads to an increase in the band gap. Electrons can transit easily from the valence band to the conduction band, which results in an enhancement of visible light absorption in a wider absorption range. Absorption spectra reach a high value in visible and infrared light regions. With the significance of the obtained results, the studied compounds may potentially find spintronic and optoelectronic applications.     

奥钢联板坯铸机驱动力报警问题的分析及改进

浇铸过程中，驱动力报警会导致紧急停浇甚至滞坯事故发生。为防止事故发生，通常采用降速、强冷等措施，但降速造成成本浪费，强冷又产生裂纹等质量缺陷，两者都难以满足生产需要。通过对铸机的各项参数对比分析，找到影响驱动力报警的主要原因为辊缝异常，轻压下模型参数、冷却工艺设置不合理等，通过调整二冷工艺、优化模型参数、加强轻压下区域扇形段辊缝维护，可以达到明显降低驱动力、消除报警的目的，从而保证连铸生产稳定。     

Transport Map sampling with PGD model reduction for fast dynamical Bayesian data assimilation

The motivation of this work is to address real-time sequential inference of parameters with a full Bayesian formulation. First, the proper generalized decomposition (PGD) is used to reduce the computational evaluation of the posterior density in the online phase. Second, Transport Map sampling is used to build a deterministic coupling between a reference measure and the posterior measure. The determination of the transport maps involves the solution of a minimization problem. As the PGD model is quasi-analytical and under a variable separation form, the use of gradient and Hessian information speeds up the minimization algorithm. Eventually, uncertainty quantification on outputs of interest of the model can be easily performed due to the global feature of the PGD solution over all coordinate domains. Numerical examples highlight the performance of the method.     

Microwave-assisted combustion synthesis of ZnAl2O4 and ZnO nanostructure particles for photocatalytic wastewater treatment

ZnAl₂O₄ and ZnO nanostructure particles and in situ crystallization of zinc aluminate and zinc oxide coating layers on sintered α-Al₂O₃ and γ-Al₂O₃ granules by the microwave-assisted combustion method were investigated. For powders, the effects of solution pH value and for coated samples the influence of support type on the structure, microstructure, and photocatalytic activity of powders were studied. Results showed that variation of synthesis pH value caused to considerable change in agglomeration, specific surface area, obtaining up to 88 and 92% yields for zinc aluminate and zinc oxide nanoparticles, respectively. γ-alumina granules were more appropriate supports than the α-alumina ones because of the better photocatalytic activities and lower extent of the attritions for both zinc aluminate and zinc oxide coating layers.     

Texture Feature Extraction Method for Ground Nephogram Based on Contourlet and the Power Spectrum Analysis Algorithm

It is important to extract texture feature from the ground-base cloud image for cloud type automatic detection. In this paper, a new method is presented to capture the contour edge, texture and geometric structure of cloud images by using Contourlet and the power spectrum analysis algorithm. More abundant texture information is extracted. Cloud images can be obtained a multiscale and multidirection decomposition. The coefficient matrix from Contourlet transform of ground nephogram is calculated. The energy, mean and variance characteristics calculated from coefficient matrix are composed of the feature information. The frequency information of the data series from the feature vector values is obtained by the power spectrum analysis. Then Support Vector Machines (SVM) classifier is used to classify according to the frequency information of the trend graph of data series. It is shown that altocumulus and stratus with different texture frequencies can be effectively recognized and further subdivided the types of clouds.     

一种有效折扣证据源的冲突证据合成方法

为解决证据组合规则中一票否决和弱决策证据在低冲突情况下出现的反直观推理的现象，提出一种有效折扣证据源的冲突证据合成方法。首先根据证据的信任函数和似然函数求得证据间的相似度，然后求出证据之间的支持程度，并确定折扣因子，最后采用Dempster组合规则合成利用折扣因子修正后的证据源。数值算例分析结果表明，改进后的证据组合方法可以有效地处理证据冲突。     

Predicting employee information security policy compliance on a daily basis: The interplay of security-related stress,emotions, and neutralization

We conceptualized security-related stress (SRS) and proposed a theoretical model linking SRS, discrete emotions, coping response, and information security policy (ISP) compliance. We used an experience sampling design, wherein 138 professionals completed surveys. We observed that SRS had a positive association with frustration and fatigue, and these negative emotions were associated with neutralization of ISP violations. Additionally, frustration and fatigue make employees more likely to follow through on their rationalizations of ISP violations by decreased ISP compliance. Our findings provide evidence that neutralization is not a completely stable phenomenon but can vary within individuals from one time point to another.     

A New NTRU-Type Public-Key Cryptosystem over the Binary Field

As the development of cloud computing and the convenience of wireless sensor netowrks, smart devices are widely used in daily life, but the security issues of the smart devices have not been well resolved. In this paper, we present a new NTRU-type public-key cryptosystem over the binary field. Specifically, the security of our scheme relies on the computational intractability of an unbalanced sparse polynomial ratio problem (DUSPR). Through theoretical analysis, we prove the correctness of our proposed cryptosystem. Furthermore, we implement our scheme using the NTL library, and conduct a group of experiments to evaluate the capabilities and consuming time of encryption and decryption. Our experiments result demonstrates that the NTRU-type public-key cryptosystem over the binary field is relatively practical and effective.     

Theoretical kinetic study of the reaction between dimethyl disulfide and OH radicals

The potential energy profile of the reaction between dimethyl disulfide and OH^? radicals is explored by utilizing ab initio and hybrid meta density functional theory methods. Having the energies and structural data of the stationary points, statistical rate theories, such as transition state theory and variable reaction coordinate-transition state theory, are employed to compute the overall rate constants, and discuss the mechanism and product channels. On the basis of the calculations, the overall rate coefficient is predicted to be 2.49?×?10^?10?cm³?molecule^?1?s^?1 at 298?K. It is found that in the most favorable pathway, the reaction proceeds via formation of the relatively unstable intermediate CH₃S^?(OH)SCH₃ decomposing rapidly to yield CH₃S^?+CH₃SOH.