检索结果-南通市图书馆

A review of tax avoidance in China

在线全文

学校读者我要写书评

暂无评论

China Journal of Accounting Research 2020年第4期13卷 327-338页

作者： Tanya Y.h.tang Department of Accounting Goodman School of BusinessBrock UniversityCanada

This paper synthesizes the major empirical findings of the burgeoning tax avoidance research in China from the accounting,finance,and economics literature over the last 13 *** surveys the evidence in four main areas:(1)the mechanisms through which Chinese firms avoid income taxes;(2)the effects of government ownership and agency problem on tax avoidance;(3)tax avoidance and political connections;and(4)the roles of book-tax conformity,tax enforcement,and corporate *** also discusses the appropriateness of tax avoidance measures in the Chinese ***,it proposes important directions for future research.

关键词： Tax avoidance Government ownership Agency problems Corporate political activity Book-tax conformity China

基于稀疏注意力卷积ViT模型的锌浮选工况识别

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

工程科学学报 2025年第2期47卷 328-338页

作者：苏越唐朝晖谢永芳高小亮张虎马炜烨汤海玚中南大学自动化学院长沙410083 中南大学数学与统计学院长沙410083

准确识别锌浮选工况并用于指导锌浮选操作,可以提高浮选效率、优化选矿过程.目前浮选现场主要通过人工肉眼观察泡沫并依据经验判断工况,这种方法主观性强,难以客观准确地评价锌浮选工况.针对该问题,本文通过研究锌浮选泡沫视觉特征和浮... 详细信息

准确识别锌浮选工况并用于指导锌浮选操作,可以提高浮选效率、优化选矿过程.目前浮选现场主要通过人工肉眼观察泡沫并依据经验判断工况,这种方法主观性强,难以客观准确地评价锌浮选工况.针对该问题,本文通过研究锌浮选泡沫视觉特征和浮选工况的密切联系,提出基于稀疏注意力卷积ViT模型的锌浮选工况识别方法.首先,所提模型融合了卷积神经网络(Convolutional neural networks,CNN)和视觉Transformer(Vision transformer,ViT)的结构和优点,同时感知泡沫局部空间信息和全局信息,完备表征泡沫图像.其次,模型引入稀疏的多头注意力机制,每个注意力头以不同的稀疏程度处理特征,从不同尺度下感知全局信息,同时引入注意力门控单元优化特征传递,最终实现锌浮选工况识别.实验结果表明,本文所提工况识别方法在锌浮选泡沫图像数据集上的准确率达到88.62%,解决了传统CNN和ViT模型不能充分利用泡沫图像全局信息,且无法自适应捕捉泡沫图像重要特征的问题,为浮选流程优化提供有力支持.

关键词：工况识别卷积神经网络视觉Transformer 稀疏注意力泡沫浮选

高空强爆炸X射线辐照铝靶板动响应的数值模拟

在线全文

学校读者我要写书评

暂无评论

爆炸与冲击 2025年第1期45卷 65-74页

作者：余润洲张昆汤文辉国防科技大学理学院湖南长沙410073

高空强爆炸所产生的X射线辐照至导弹壳体结构时产生的汽化反冲冲量(blow-off impulse,BOI)及热激波,能够引起目标的动响应破坏。现有的Whitener、BBAY和MBBAY理论模型仅能给出一维近似BOI值,无法处理复杂三维情况并给出对应的热激波峰... 详细信息

高空强爆炸所产生的X射线辐照至导弹壳体结构时产生的汽化反冲冲量(blow-off impulse,BOI)及热激波,能够引起目标的动响应破坏。现有的Whitener、BBAY和MBBAY理论模型仅能给出一维近似BOI值,无法处理复杂三维情况并给出对应的热激波峰值压力p,因此,对该问题的研究非常依赖数值计算。利用X射线热激波数值计算程序TshOCK3D对矩形铝靶板在0.1~3.0 keV范围的普朗克黑体温度和220~400 J/cm^(2)辐射能通量下的汽化反冲冲量及峰值压力进行计算,并与理论模型作了对比分析。结果表明,TshOCK3D程序可以得到可靠的结果,正辐照靶板中心处近似一维工况下的BOI与Whitener、BBAY和MBBAY三个理论模型下的BOI基本相符。通过单变量分析可得,靶板中BOI和峰值压力p均与入射能通量呈近似线性关系;而对于不同的黑体温度,BOI和峰值压力则在1.5~2.0 keV处存在极大值。

关键词： X射线汽化反冲冲量热激波 TshOCK3D

Quantitative hazard assessment for Zonguldak Coal Basin underground mines

同方期刊数据库博看期刊评论

在线全文

学校读者我要写书评

暂无评论

International Journal of Mining science and Technology 2019年第3期29卷 453-467页

作者： h.h.Erdogan h.s.Duzgun A.s.selcuk-Kestel Directorate for strategy Development Ministry of Energy and Natural ResourcesAnkara 06520Turkey Department of Mining Engineering Colorado School of MinesIL 80401USA Institute of Applied Mathematics Middle East Technical UniversityAnkara 06531Turkey

Underground coal mining is one of the most dangerous occupations throughout the *** reasons behind an underground occupational accident are too complex to analyze mainly due to many uncertainties which may arise from geological,operational conditions of the mine or individual characteristics of *** study proposes implementing a quantitative methodology for the analysis and assessment of hazards associated with occupational *** application of the proposed approach is performed on the mines of Turkish hard Coal Enterprises(TTK).The accidents in TTK between the years 2000 and 2014 are firstly statistically analyzed with respect to the number,type and location of accidents,age,experience,education level and main duty of the casualties and also injuries resulting from such *** hazards are classified as individual,operational and locational hazards and quantified using contingency tables,conditional and total probability *** and upper boundaries of hazards are determined and event trees for each hazard class are *** hazard evaluation results show that Armutcuk,Karadon and Uzulmez mines have relatively high hazard levels while Amasra and Kozlu mines have relatively lower hazard values.

关键词： Underground coal mining Occupational accidents hazard assessment Contingency tables Zonguldak Coal Basin

Modeling biomembranes and red blood cells by coarse-grained particle methods

在线全文

学校读者我要写书评

暂无评论

Applied Mathematics and Mechanics(English Edition) 2018年第1期39卷 3-20页

作者： h.LI h.Y.ChANG J.YANG L.LU Y.h.tang G.LYKOTRAFITIs Division of Applied Mathematics Brown University Department of Materials science and Engineering Massachusetts Institute of Technology Department of Mechanical Engineering University of Connecticut

In this work, the previously developed coarse-grained （CG） particle models for biomembranes and red blood cells （RBCs） are reviewed, and the advantages of the CG particle methods over the continuum and atomistic simulations for modeling biological phenomena are discussed. CG particle models can largely increase the length scale and time scale of atomistic simulations by eliminating the fast degrees of freedom while preserving the mesoscopic structures and properties of the simulated system. Moreover, CG particle models can be used to capture the microstructural alternations in diseased RBCs and simulate the topological changes of biomembranes and RBCs, which are the major challenges to the typical continuum representations of membranes and RBCs. The power and versatility of CG particle methods are demonstrated：through simulating the dynamical processes mvolving significant topological .changes e.g. lipid self-assembly vesicle fusion and membrane budding.

关键词： coarse-grained molecular dynamics,lipid bilayer red blood cell membrane membrane fusion

Non-noble metal anode based dual-ion batteries： promising high-energy and low-cost energy storage devices

在线全文

学校读者我要写书评

暂无评论

science China Materials 2017年第4期60卷 368-370页

作者： Zhiyong tang CAs Key Laboratory of Nanosystem and hierarchical Fabrication CAS Center for Excellence in Nanoscience National Center for Nanoscience and Technology Beijing 100190 China

Lithium-ion batteries(LIBs),as one of the most commonly used electrochemical energy storage devices,have dominated todays markets for portable electronics and electric vehicles[1].Llowever,their energy density cannot yet satisfy the increasing requirement,so it is imperative for developing next-generation batteries with high energy density together with long cycling life and good *** recent years,a novel type of battery called as

关键词：科学研究材料学工程材料中国

Global change hydrology:Terrestrial water cycle and global change

在线全文

学校读者我要写书评

暂无评论

science China Earth sciences 2020年第3期63卷 459-462页

作者： Qiuhong tang Key Laboratory of Water Cycle and Related Land surface Processes Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of Sciences University of Chinese Academy of sciences

*** Global Change hydrology(GCh)is an emerging interdisciplinary field that links global change research and *** integrates hydrology,climatology,and geography to study the interactions between the terrestrial water cycle and global change across various time and space *** main objective of GCh is to understand the natural and anthropogenic causes of the changing terrestrial water cycle and the associated influences and feedbacks in the Earth system.

关键词： hydrology terrestrial Global

Multi-objective optimization strategies using adjoint method and game theory in aerodynamics

在线全文

学校读者我要写书评

暂无评论

Acta Mechanica sinica 2006年第4期22卷 307-314页

作者： Zhili tang College of Aerospace Engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 China

There are currently three different game strategies originated in economics：（1） Cooperative games （Pareto front）, （2） Competitive games （Nash game） and （3） hierarchical games （stackelberg game）. Each game achieves different equilibria with different performance, and their players play different roles in the games. here, we introduced game concept into aerodynamic design, and combined it with adjoint method to solve multi- criteria aerodynamic optimization problems. The performance distinction of the equilibria of these three game strategies was investigated by numerical experiments. We computed Pareto front, Nash and stackelberg equilibria of the same optimization problem with two conflicting and hierarchical targets under different parameterizations by using the deterministic optimization method. The numerical results show clearly that all the equilibria solutions are inferior to the Pareto front. Non-dominated Pareto front solutions are obtained, however the CPU cost to capture a set of solutions makes the Pareto front an expensive tool to the designer.

关键词： Multi-objective optimization. Pareto front Nash game stackelberg game Adjoint method

Direct knitting privileged molecular catalysts into recyclable single-site catalysts with enhanced activity

在线全文

学校读者我要写书评

暂无评论

science China Chemistry 2020年第4期63卷 419-420页

作者： Yong tang state Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China

An ideal strategy for catalyst immobilization is taking advantage of the widely well studied homogeneous molecular catalysts and transforming them directly into highly efficient and recyclable heterogeneous ***,the obtained heterogeneous catalysts often have inferior activity due to altered chemical environment around active centers and decreased mass/heat transfer[1,2].

关键词： catalysts molecular centers