会计职业道德对提高会计信息质量的影响

会计信息质量与环境、会计系统等诸多因素有关,同时会计职业道德也是一个非常重要的因素。它作为一种引导和制约会计行为的社会规范,与会计信息的质量息息相关。我国会计信息质量的现状不容乐观,重整我国会计职业道德,将对我国会计信息质量的提高起到积极的推动作用。文中分析了会计职业道德的特征和现状,提出了重整会计职业道德的几点思考.     

Nonlinear averaging theorems, and the determination of parameter convergence rates in adaptive control

The paper presents nonlinear averaging theorems for two-time scale systems, where the dynamics of the fast system are allowed to vary with the slow system. The results are applied to the Narendra-Valavani adaptive control algorithm, and estimates of the parameter convergence rates are obtained which do not rely on a linearization of the system around the equilibrium, and therefore are valid in a larger region in the parameter space.     

Machine learning-based real-time visible fatigue crack growth detection

Many large-scale and complex structural components are applied in the aeronautics and automobile industries.However,the repeated alternating or cyclic loads in ...     

Microwave radiation as heating method in the synthesis of titanium dioxide nanoparticles from hexafluorotitanate-organic salts

Nanocrystalline anatase was obtained from ionic liquid-like precursors containing hexafluorotitanate-organic salts and less than 25 wt.% of water, and using boric acid as fluoride scavenger. Two alternative heating methods were explored using either a conventional oven or a domestic microwave apparatus. A significant reduction in the reaction time from 24 h to only few minutes was obtained using the microwave route. The as-prepared materials were characterized by X-ray diffraction, transmission electron microscopy, nitrogen sorption analysis, and attenuated total reflectance Fourier transformed infrared, X-ray photoelectronic and Raman spectroscopes. The convenience of using the microwave heating option was a function of the organic cation present in the precursor. Thus, organic ammonium cations containing only hydrocarbon substituents, such as diethylammonium, phenylammonium and benzyltrimethylammonium led to the precipitation of nanocrystalline anatase powder with high specific surface area (up to 120 m² g⁻¹) in a short processing time (1-3 min). Otherwise, alcohol and carboxylate functionalized cations decomposed under microwave treatment. Moreover, the choice of the organic cation allowed tuning several properties of the end material, such as particle size and pore morphology.     

Direct vapor phase growth process and robust photoluminescence properties of large area MoS2 layers

There has been growing research interest in the use of molybdenum disulfide in the fields of optoelectronics and energy harvesting devices, by virtue of its indirect-to-direct band gap tunability. However, obtaining large area thin films of MoS2 for future device applications still remains a challenge. In the present study, the amounts of the precursors （S and MOO3） were varied systematically in order to optimize the growth of highly crystalline and large area MoS2 layers by the chemical vapor deposition method. Careful control of the amounts of precursors was found to the key factor in the synthesis of large area highly crystalline flakes. The thickness of the layers was confirmed by Raman spectroscopy and atomic force microscopy. The optical properties and chemical composition were studied by photoluminescence （PL） and X-ray photoelectron spectroscopy. The emergence of strong direct excitonic emissions at 1.82 eV （A-exciton, with a normalized PL intensity of -55 × 10^3） and 1.98 eV （B-exciton, with a normalized PL intensity of -5 × 10^3） of the sample at room temperature clearly indicates the high luminescence quantum efficiency. The mobility of the films was found to be 0.09 cm^2/（V.s） at room temperature. This study provides a method for the controlled synthesis of high-quality two-dimensional （2D） transition metal dichalcogenide materials, useful for applications in nanodevices, optoelectronics and solar energv conversion.     

融合双分支动态偏好的会话推荐

针对基于会话的推荐算法仅对用户单一偏好进行静态建模而无法捕捉用户受环境影响偏好产生的波动, 从而降低推荐准确性的问题. 提出融合双分支动态偏好的会话推荐方法: 首先, 通过异构超图来建模不同类型信息, 设计双分支聚合机制获取以及整合异构超图中信息并且学习多类型节点之间的关系, 再用价格嵌入增强器来加强类别和价格之间关系; 其次, 设计双层偏好编码器, 其中采用多尺度时序Transformer提取用户动态价格偏好, 利用软注意机制和反向位置编码学习用户动态兴趣偏好; 最后, 用门控机制融合用户多类型动态偏好, 向用户进行推荐. 通过在Cosmetics和Diginetica-buy两个数据集上进行实验, 结果证明与其他对比算法相比在Precision和MRR评价指标中有显著的提升.     

MicroRNA-Based Diagnosis and Therapy

MicroRNAs (miRNAs) are a group of endogenous non-coding RNAs that regulate gene expression. Alteration in miRNA expression results in changes in the profile of genes involving a range of biological processes, contributing to numerous human disorders. With high stability in human fluids, miRNAs in the circulation are considered as promising biomarkers for diagnosis, as well as prognosis of disease. In addition, the translation of miRNA-based therapy from a research setting to clinical application has huge potential. The aim of the current review is to: (i) discuss how miRNAs traffic intracellularly and extracellularly; (ii) emphasize the role of circulating miRNAs as attractive potential biomarkers for diagnosis and prognosis; (iii) describe how circulating microRNA can be measured, emphasizing technical problems that may influence their relative levels; (iv) highlight some of the circulating miRNA panels available for clinical use; (v) discuss how miRNAs could be utilized as novel therapeutics, and finally (v) update those miRNA-based therapeutics clinical trials that could potentially lead to a breakthrough in the treatment of different human pathologies.     

自定义服务质量模型的网格工作流调度算法

随着网格服务应用的发展,在网格工作流中,复杂的任务可以由多个独立的服务,通过工作流引擎等方式组合成新服务后完成。在组合服务的过程中,由不同服务提供商提供的候选服务,具有不同的服务质量参数,在网格工作流调度中,需要满足用户定义的服务质量约束。提出了方便用户定义的服务质量模型,并且在该模型的基础上,改进了网格工作流调度算法,通过实验分析证明改进后的算法优于传统的调度算法。