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结合神经网络方法和扩大训练基组构建新B3LYP泛函

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物理化学学报 2010年第1期26卷 188-192页

作者：张家虎王秀军华南理工大学化学与化工学院应用化学系广州510640

神经网络方法成功地应用于修正密度泛函理论B3LYP方法中的三个参数(a0、ax和ac)以构建新B3LYP交换相关泛函.本文采用包含输入层、隐藏层和输出层的三层式神经网络结构.总电子数、多重度、偶极矩、动能、四极矩和零点能被选为物理描述符.... 详细信息

神经网络方法成功地应用于修正密度泛函理论B3LYP方法中的三个参数(a0、ax和ac)以构建新B3LYP交换相关泛函.本文采用包含输入层、隐藏层和输出层的三层式神经网络结构.总电子数、多重度、偶极矩、动能、四极矩和零点能被选为物理描述符.296个能量数据被随机地分成两组,246个能量数据作为训练集以确定神经网络的最优结构和最优突触权重,50个能量数据作为测试集以测试神经网络的预测能力.修正后的三个参数觔0、觔x、觔c从输出层处得到,并用于计算体系的热化学性质如原子化能(AE)、电离势(IP)、质子亲合能(PA)、总原子能(TAE)和标准生成热(ΔfH苓).修正后的计算结果优于传统B3LYP/6-311+G(3df,2p)方法的计算结果.经过神经网络修正后,296个物种的总体均方根偏差从41.0 ***-1减少到14.2 ***-1.

关键词： B3LYP泛函神经网络描述符训练基组

上市公司审计委托关系的重构——加强审计独立性的路径

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审计与经济研究 2007年第1期22卷 49-51页

作者：汪俊秀广东金融学院会计系广东广州510521

本文首先分析了我国上市公司现行审计委托模式的缺陷,指出由上市公司直接委托会计师事务所审计的现行审计委托模式容易造成审计独立性缺失。然后结合我国实际,提出实行在中国证监会下设立审计委员会统一管理上市公司财务报表审计的新的... 详细信息

本文首先分析了我国上市公司现行审计委托模式的缺陷,指出由上市公司直接委托会计师事务所审计的现行审计委托模式容易造成审计独立性缺失。然后结合我国实际,提出实行在中国证监会下设立审计委员会统一管理上市公司财务报表审计的新的审计委托模式。通过重构上市公司审计委托关系,增强注册会计师审计独立性。

关键词：重构审计委托模式审计独立性

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特殊图类的符号控制数

纯粹数学与应用数学 2005年第1期21卷 59-61页

作者：王军秀安徽工业大学数理系安徽马鞍山243002

图G的符号控制数γS(G)有着许多重要的应用背景.已知它的计算是NP-完全问题,因而确定其上下界有重要意义.本文研究了1)一般图G的符号控制数,给出了一个新的下界;2)确定了Cn图的符号控制数的精确值.

关键词：符号控制函数符号控制数 Cn图

Boron shielding design for neutron and gamma detectors of a pulsed neutron tool

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Nuclear Science and Techniques 2025年第1期36卷 115-126页

作者： Xin-Yang wang jun-Yan Chen Qiong Zhang University of Electronic Science and Technology of China Chengdu 611731China

Shielding materials are critical for downhole pulsed neutron tool design because they directly influence the accuracy of formation measurements.A well-designed shield configuration ensures that the response of the tool is maximally representative of the formation without being affected by the tool and borehole *** study investigated the effects of boron-containing materials on neutron and gamma detectors based on a newly designed logging-while-drilling tool that is currently undergoing *** the boron content increased,the ability to absorb thermal neutrons increased *** simulation,it was proven that boron carbide(B_(4)C)can be used as an effective boron shielding material for thermal neutrons,and is therefore employed in this *** shield against thermal neutrons migrating from the mud pipes,the optimal shielding thicknesses for the near-and far-neutron detectors were determined to be 5 and 4 *** a porosity of 25 p.u.,near-neutron sensitivity exhibited a 5.6%***,to shield the capture gamma generated by thermal neutrons once they enter the tool from the mud pipe and formation,internal and external shields for the gamma detector were *** results show that the internal shield requires a boron content of 75%,whereas the external shield has a thickness of 14.2 mm thickness and a boron content of 25%to minimize the tool effect.

关键词： Nuclear well logging Pulsed neutron tool Boron shielding

Civil aviation emissions in China in 2019:Characteristics and abatement potential

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Journal of Environmental Sciences 2025年第5期151卷 225-237页

作者： Haowen An Yu wang Yaxin wang jun Liu Xiaolong Tang Honghong Yi Department of Environmental Engineering School of Energy and Environmental EngineeringUniversity of Science and Technology BeijingBeijing 100083China Key Laboratory of Beijing Municipal Industry Pollutant Resources Processing Beijing 100083China

Civil aviation is one of the industries facing the greatest challenge in reaching carbon neutrality by the middle of this century,and this sector also contributes to adverse impacts on the regional air quality and human *** exhibits the second highest air passenger turnover *** understanding of civil aviation emissionsmust be urgently enhanced,and themitigation potential should be *** this study,on the basis of real domestic flight information for 2019,we built a greenhouse gas and air pollution emission inventory for the civil aviation sector in China with the fuel flowmethod based on the cruise and other *** thoroughly analyzed emissions by region,aircraft and engine types,and aircraft age,based on which we designed four measures to evaluate the abatement *** found that the hydrocarbon(HC),CO,NO_(x),SO_(2),particulate matter(PM)and CO_(2)emissions in 2019 reached 79.9 kt(95%CI[51.6–114.5]),176.3 kt(95%CI[114.5–248.2]),304.2 kt(95%CI[203.4–420.7]),23.2 kt(95%CI[14.2–33.7]),1.0 kt(95%CI[0.61–1.44])and 87.0 Mt(95%CI[57.4–119.6]),*** cruise phase was the major emission phase,accounting for 67%-87%of the total pollutant *** four measures were jointly implemented,the HC,CO,NO_(x),SO_(2),PM and CO_(2)emissions could be reduced by 61%,54%,55%,45%,32%and 38%,*** lower-emission aircraft and switching travel modes could substantially reduce civil aviation emissions in China.

关键词： Emission inventory Fuel flow method Cruise emission Age structure Reduction measures

Adsorption of typical NDMA precursors by superfine powdered activated carbon:Critical role of particle size reduction

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Journal of Environmental Sciences 2025年第1期147卷 101-113页

作者： Ying wang Zhichen Zhang Zhihang Yin jun wang Xiaojian Zhang Chao Chen State Key Joint Laboratory of Environmental Simulation and Pollution Control School of EnvironmentTsinghua UniversityBeijing 100084China Research Institute for Environmental Innovation(Suzhou) TsinghuaSuzhou 215163China

Control of N-nitrosodimethylamine(NDMA)in drinking water could be achieved by removing its precursors as one practical ***,superfine powdered activated carbons with a diameter of about 1μm(SPACs)were successfully prepared by grinding powdered activated carbon(PAC,D50=24.3μm)and applied to remove model NDMA precursors,***(RAN)and nizatidine(NIZ).Results fromgrain diameter experiments demonstrated that the absorption velocity increased dramatically with decreasing particle size,and the maximum increase in k2 was 26.8-folds for RAN and 33.4-folds for ***,kinetic experiments explained that rapid absorption could be attributed to the acceleration of intraparticle diffusion due to the shortening of the diffusion ***,performance comparison experiments suggested that the removal of RAN and NIZ(C_(0)=0.5 mg/L)could reach 61.3%and 60%,respectively,within 5 min,when the dosage of SAPC-1.1(D_(50)=1.1μm)was merely 5 mg/L,while PAC-24.3 could only eliminate 17.5%and 18.6%.The adsorption isotherm was well defined by Langmuir isotherm model,indicating that the adsorption of RAN/NIZ was a monolayer coverage *** adsorption of RAN or NIZ by SAPC-1.1 and PAC-24.3 was strongly pH dependent,and high adsorption capacity could be observed under the condition of pH>pk_(a)+*** coexistence of humic acid(HA)had no significant effect on the adsorption performance because RAN/NIZ may be coupled with HA and removed *** coexistence of anions had little effect on the adsorption *** study is expected to provide an alternative strategy for drinking water safety triggered by NDMA.

关键词： Adsorption NDMA Kinetics Superfine powdered activated carbon Intraparticle diffusion Drinking water

Hausdorff Measure of Space Anisotropic Gaussian Processes with Non-stationary Increments

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Acta Mathematicae Applicatae Sinica 2025年第1期41卷 114-132页

作者： jun wang Zhen-long CHEN Wei-jie YUAN Guang-jun SHEN School of Mathematics and Physics Anhui Polytechnic UniversityWuhu 241000China School of Statistics and Mathematics Zhejiang Gongshang UniversityHangzhou 310018China Department of Mathematics Anhui Normal UniversityWuhu 241000China

Let X={X(t),t∈R+} be a centered space anisotropic Gaussian process values in R^(d) with non-stationary increments,whose components are independent but may not be identically *** certain conditions,then almost surely c_(1)≤ϕ-m(X([0,1]))≤c_(2),where ϕ denotes the exact Hausdorff measure associated with function ϕ(s)=s1/α_(k)+Σ_(i=1)k(1-αi/αk)log log 1/s for some 1≤k≤d,(α_(1),…,α_(d))∈(0,1]^(d).We also obtain the exact Hausdorff measure of the graph of X on[0,1].

关键词： Hausdorff measure self-similar Gaussian processes non-stationary increment Lamperti theorem

Nrf2/ARE通路在消化道肿瘤预防中的研究进展

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浙江大学学报（医学版） 2012年第4期41卷 453-463页

作者：高鹏唐修文王秀君浙江大学医学院药理学系浙江杭州310058 浙江大学医学院生物化学与遗传生物学系浙江杭州310058

转录因子红细胞系-2 p45(NF-E2)相关因子-2(nuclear factor erythroid-2 related factor 2,Nrf2)通过与抗氧化反应元件ARE(antioxidant response element)结合,调控一系列二相解毒酶和抗氧化酶基因的表达,从而保护机体免受化学致癌剂的伤害,大量研究证明Nrf2对预防肿瘤发生起重要的作用。目前,肠癌、胃癌、食管癌等消化道肿瘤是我国高发癌症类型,服用天然或人工合成的Nrf2激活剂有可能是防止此类疾病发生的有效措施。文中基于动物模型和临床的研究报道,综述了Nrf2/ARE通路在消化道肿瘤化学预防中的最新进展。

关键词：消化系统肿瘤/预防和控制核胞浆转运蛋白类氧化性应激 Nrf2 癌症化学预防消化道肿瘤

A Multi-Condition Sequential Network Ensemble for Industrial Energy Storage Prediction Considering the Condition Switching Characteristics

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IEEE/CAA Journal of Automatica Sinica 2025年第2期12卷 369-380页

作者： Tianyu wang Fan Zhou Yangjie Wu jun Zhao Wei wang IEEE the School of Control Science and Engineering Dalian University of Technology the School of Information Science and Engineering Dalian Polytechnic University

As a crucial storage and buffering apparatus for balancing the production and consumption of byproduct gases in industrial processes, accurate prediction of gas tank levels is essential for optimizing energy system scheduling. Considering that the continuous switching of the pressure and valve status(mechanism knowledge) would bring about multiple working conditions of the equipment, a multi-condition time sequential network ensembled method is proposed. In order to especially consider the time dependence of different conditions, a centralwise condition sequential network is developed, where the network branches are specially designed based on the condition switching sequences. A branch combination transfer learning strategy is developed to tackle the sample imbalance problem of different condition data. Since the condition or status data are real-time information that cannot be recognized during the prediction process, a pre-trained and ensemble learning approach is further proposed to fuse the outputs of the multi-condition networks and realize a transient-state involved prediction. The performance of the proposed method is validated on practical energy data coming from a domestic steel plant, comparing with the state-of-the-art algorithms. The results show that the proposed method can maintain a high prediction accuracy under different condition switching cases, which would provide effective guidance for the optimal scheduling of the industrial energy systems.

关键词： Ensemble learning industrial energy prediction multi-working condition structural deep network transfer learning