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怎样加强会计电算化下企业内部控制
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作者 梁志杰 《科技咨询导报》 2007年第7期147-147,共1页
严格的内部控制关系到企业财产物资的安全完整,关系到会计系统对企业经济活动反映的正确性和可靠性。由于电算化会计系统的特殊性,建立整套适合电算化会计系统的内部控制制度尤为重要。
关键词 计电算
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会计电算化在企业中的应用 被引量:1
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作者 吕盛华 《合作经济与科技》 2014年第23期148-149,共2页
当今电子计算机已经在社会各个方面都有了非常广泛的应用,同时相比于手工会计而言,会计电算化有着更多的优点,也逐渐开始得到普及,进而运用到会计行业中的多个环节。但是在我国会计电算化应用时间较晚,其中存在的问题和不足还是比较多... 当今电子计算机已经在社会各个方面都有了非常广泛的应用,同时相比于手工会计而言,会计电算化有着更多的优点,也逐渐开始得到普及,进而运用到会计行业中的多个环节。但是在我国会计电算化应用时间较晚,其中存在的问题和不足还是比较多的。本文首先阐述会计电算化的重要作用,详细分析现阶段会计电算化在企业应用中存在的问题,然后针对这些问题提出相应的对策。 展开更多
关键词 计电算 现状 存在问题 对策
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探究会计电算化课堂教学改革
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作者 李迎男 《中文科技期刊数据库(文摘版)教育》 2015年第11期256-256,共1页
随着教育改革的不断深入,传统的高职会计电算化教学模式存在一定的弊端,影响了高职院校会计电算化的教学质量。为提高学生学习质量,以“学生为主体”的会计电算化课程应当将传统的课堂教学模式与新型的教学方式如微课、世界大学生空间... 随着教育改革的不断深入,传统的高职会计电算化教学模式存在一定的弊端,影响了高职院校会计电算化的教学质量。为提高学生学习质量,以“学生为主体”的会计电算化课程应当将传统的课堂教学模式与新型的教学方式如微课、世界大学生空间进行有效的结合,以激发学生的学习积极性,实现高质量的教学效果。 展开更多
关键词 计电算 微课 世界大学生空间 教改
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刍议会计电算化对内审工作的影响
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作者 宋惠敏 《冶金财会》 1999年第10期42-43,共2页
近年来,随着计算机会计系统的应用和普及,利用计算机进行审计的技术和方法也越来越广泛地应用于审计实务中,同时,也给内审工作带来许多影响。 一、电子计算机会计系统特点及其对内审工作的影响 (一)组织结构方面 1.功能和信息的集中。... 近年来,随着计算机会计系统的应用和普及,利用计算机进行审计的技术和方法也越来越广泛地应用于审计实务中,同时,也给内审工作带来许多影响。 一、电子计算机会计系统特点及其对内审工作的影响 (一)组织结构方面 1.功能和信息的集中。计算机处理财务信息所需的人员减少。 展开更多
关键词 内审工作 计电算 议会 经济业务 算机会系统 内审人员 账户体系 人员 机器程序 原始凭证
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浅析会计电算化发展
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作者 刘君 张楠 《品牌》 2015年第9期166-,共1页
随着信息技术的不断发展,企业管理系统逐渐向信息化方向发展,而企业中的财务管理工作也逐渐向单纯的记录工作转向解析、控制和筹划等复合工作,这也为会计电算化的发展迎来了契机。会计电算化就是在会计工作中以电子计算机代替手工对会... 随着信息技术的不断发展,企业管理系统逐渐向信息化方向发展,而企业中的财务管理工作也逐渐向单纯的记录工作转向解析、控制和筹划等复合工作,这也为会计电算化的发展迎来了契机。会计电算化就是在会计工作中以电子计算机代替手工对会计业务进行处理的形式,并对会计信息进行整理、加工、预测和分析,并为管理者的决策提供依据。本文对会计电算化进行了分析,并了解了现阶段会计电算化的现状,最后对会计电算化的发展做出了预测。 展开更多
关键词 计电算 发展 现状
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电力市场中计算输电电价的一种新方法 被引量:28
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作者 任震 吴国玥 黄雯莹 《中国电机工程学报》 EI CSCD 北大核心 2003年第1期37-40,170,共5页
该文基于边际成本理论,提出了一种计算输电电价的新方法,在保留边际成本定价中的经济信息的同时,综合考虑了无功电价,又考虑了电网的年收支平衡,最后,通过潮流跟踪法,确定有功、无功电价及固定成本在各个用户间的分配,使定价模型更加合... 该文基于边际成本理论,提出了一种计算输电电价的新方法,在保留边际成本定价中的经济信息的同时,综合考虑了无功电价,又考虑了电网的年收支平衡,最后,通过潮流跟踪法,确定有功、无功电价及固定成本在各个用户间的分配,使定价模型更加合理、完善。经IEEE6节点系统算例证明,该文所提的模型和算法是正确而有效的,具有重要的理论意义和工程实际价值,特别是对于在厂网分开后电网建设以及维护电网稳定的资金筹措有相当的指导价值。 展开更多
关键词 电网 无功功率 边际成本理论 潮流 电力市场 输电电价
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Large and nonlinear electric field response in a two-dimensional ferroelectric Rashba material
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作者 Li Sheng Xiaomin Fu +2 位作者 Chao Jia Xingxing Li Qunxiang Li 《中国科学技术大学学报》 CAS CSCD 北大核心 2024年第6期8-11,21,I0009,共6页
The achievement of electrical spin control is highly desirable.One promising strategy involves electrically mod-ulating the Rashba spin orbital coupling effect in materials.A semiconductor with high sensitivity in its... The achievement of electrical spin control is highly desirable.One promising strategy involves electrically mod-ulating the Rashba spin orbital coupling effect in materials.A semiconductor with high sensitivity in its Rashba constant to external electric fields holds great potential for short channel lengths in spin field-effect transistors,which is crucial for preserving spin coherence and enhancing integration density.Hence,two-dimensional(2D)Rashba semiconductors with large Rashba constants and significant electric field responses are highly desirable.Herein,by employing first-principles calculations,we design a thermodynamically stable 2D Rashba semiconductor,YSbTe_(3),which possesses an indirect band gap of 1.04 eV,a large Rashba constant of 1.54 eV·Åand a strong electric field response of up to 4.80 e·Å^(2).In particular,the Rashba constant dependence on the electric field shows an unusual nonlinear relationship.At the same time,YSbTe_(3)has been identified as a 2D ferroelectric material with a moderate polarization switching energy barrier(~0.33 eV per formula).By changing the electric polarization direction,the Rashba spin texture of YSbTe_(3)can be reversed.These out-standing properties make the ferroelectric Rashba semiconductor YSbTe_(3)quite promising for spintronic applications. 展开更多
关键词 computational chemistry Rashba effect FERROELECTRICS SPINTRONICS
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Deep learning model based on PET/CT and combination with Cox proportional hazard model for predicting progression of lung invasive adenocarcinoma after surgery
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作者 LI Yingci WU Dongbo GONG Feifei 《中国医学影像技术》 CSCD 北大核心 2024年第8期1194-1198,共5页
Objective To observe the efficacy of deep learning(DL)model based on PET/CT and its combination with Cox proportional hazard model for predicting progressive disease(PD)of lung invasive adenocarcinoma within 5 years a... Objective To observe the efficacy of deep learning(DL)model based on PET/CT and its combination with Cox proportional hazard model for predicting progressive disease(PD)of lung invasive adenocarcinoma within 5 years after surgery.Methods The clinical,PET/CT and 5-year follow-up data of 250 patients with lung invasive adenocarcinoma were retrospectively analyzed.According to PD or not,the patients were divided into the PD group(n=71)and non-PD group(n=179).The basic data and PET/CT findings were compared between groups,among which the quantitative variables being significant different between groups were transformed to categorical variables using receiver operating characteristic(ROC)curve and corresponding cut-off value.Multivariant Cox proportional hazard model was used to select independent predicting factors of PD of lung invasive adenocarcinoma within 5 years after surgery.The patients were divided into training,validation and test sets at the ratio of 6∶2∶2,and PET/CT data in training set and validation set were used to train model and tuning parameters to build the PET/CT DL model,and the combination model was built in serial connection of DL model and the predictive factors.In test set,the efficacy of each model for predicting PD of lung invasive adenocarcinoma within 5 years after surgery was assessed and compared using the area under the curve(AUC).Results Patients'gender and smoking status,as well as the long diameter,SUV max and SUV mean of lesions measured on PET images,the long diameter,short diameter and type of lesions showed on CT were statistically different between groups(all P<0.05).Smoking(HR=1.787[1.053,3.031],P=0.031)and lesion SUV max>4.15(HR=5.249[1.062,25.945],P=0.042)were both predictors of PD of lung invasive adenocarcinoma within 5 years after surgery.In test set,the AUC of PET/CT DL model for predicting PD was 0.847,of the combination model was 0.890,of the latter was higher than of the former(P=0.036).Conclusion DL model based on PET/CT had high efficacy for predicting PD of lung invasive adenocarcinoma within 5 years after surgery.Combining with Cox proportional hazard model could further improve its predicting efficacy. 展开更多
关键词 adenocarcinoma of lung positron-emission tomography and computed tomography deep learning disease progression
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First principles investigation of binary intermetallics in Mg-Al-Ca-Sn alloy:Stability,electronic structures,elastic properties and thermodynamic properties 被引量:8
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作者 王峰 孙士杰 +3 位作者 于波 张峰 毛萍莉 刘正 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第1期203-212,共10页
The structural stability, electronic structures, elastic properties and thermodynamic properties of the main binary phases Mg_(17)Al_(12), Al_2Ca, Mg_2 Sn and Mg_2 Ca in Mg-Al-Ca-Sn alloy were determined from the ... The structural stability, electronic structures, elastic properties and thermodynamic properties of the main binary phases Mg_(17)Al_(12), Al_2Ca, Mg_2 Sn and Mg_2 Ca in Mg-Al-Ca-Sn alloy were determined from the first-principles calculation. The calculated lattice parameters are in good agreement with the experimental and literature values. The calculated heats of formation and cohesive energies show that Al_2Ca has the strongest alloying ability and structural stability. The densities of states(DOS), Mulliken electron occupation number, metallicity and charge density difference of these compounds are given. The elastic constants of Mg_(17)Al_(12), Al_2Ca, Mg_2 Sn and Mg_2 Ca phases are calculated, and the bulk moduli, shear moduli, elastic moduli and Poisson ratio are derived. The calculations of thermodynamic properties show that the Gibbs free energies of Al_2Ca and Mg_2 Sn are lower than that of Mg_(17)Al_(12), which indicates that Al_2Ca and Mg_2 Sn are more stable than Mg_(17)Al_(12) phase. Hence, the heat resistance of Mg-Al-based alloys can be improved by adding Ca and Sn additions. 展开更多
关键词 Mg-Al alloy first-principles calculation electronic structure elastic properties thermodynamic properties
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A first-principles study on electronic structure and elastic properties of Al_4Sr, Mg_2Sr and Mg_(23)Sr_6 phases 被引量:1
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作者 周惦武 刘金水 彭平 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第12期2677-2683,共7页
The electronic structures and mechanical properties of Al4Sr, Mg2Sr and Mg23Sr6 phases were determined by the use of first-principles calculations. The calculated heat of formation and cohesive energy indicate that Al... The electronic structures and mechanical properties of Al4Sr, Mg2Sr and Mg23Sr6 phases were determined by the use of first-principles calculations. The calculated heat of formation and cohesive energy indicate that Al4Sr has the strongest alloying ability as well as the highest structural stability. The elastic parameters were calculated, and then the bulk modulus, shear modulus, elastic modulus and Poisson ratio were derived. The ductility and plasticity were discussed. The results show that Al4Sr and Mg2Sr phases both are ductile, on the contrary, Mg23Sr6 is brittle, and among the three phases, Mg2Sr is a phase with the best plasticity. 展开更多
关键词 magnesium alloy first-principles calculation electronic structure elastic property
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EDLC charging performance for microgrid applications 被引量:9
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作者 徐青山 卞海红 赵伟然 《Journal of Southeast University(English Edition)》 EI CAS 2010年第3期415-420,共6页
In order to review storage performance of the electric double layer capacitor (EDLC) in microgrid applications, charging time and storage efficiency issues are mainly studied aiming at three different charging modes... In order to review storage performance of the electric double layer capacitor (EDLC) in microgrid applications, charging time and storage efficiency issues are mainly studied aiming at three different charging modes, including the constant voltage charging mode (CVCM), the constant current charging mode (CCCM) and the constant power charging mode (CPCM), based on the practical EDLC product. Numerical calculation methods are presented for different charging modes, and the charging efficiency is also reviewed with strict mathematical deductions, which is validated to be accurate enough and applicable through a simple case with the PV/EDLC system illustration. Finally, trade-off problems between charging time and energy loss are also studied. Research results show that the CPCM is more suitable for microgrid networks compared with the traditional constant-voltage and constant-current charging modes. The hybrid charging method is recommended to save energy and keep high efficiency relatively at the same time. However, how to manage the combination percentage of different charging modes in a reasonable way should be dealt with according to the practical requirements. 展开更多
关键词 electric double layer capacitor (EDLC) energy storage charge evaluation numerical calculation trade-off
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Magnetism and Stability of Diluted Magnetic Semiconductor (Ga_(1-x)Fe_x)As 被引量:1
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作者 危书义 闫玉丽 +2 位作者 王天兴 夏从新 汪建广 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2004年第12期1586-1590,共5页
Magnetism and the stability of (Ga 1-xFe x)As are investigated using the first principles LMTO-ASA band calculation by assuming supercell structures.Four concentrations of the 3d impurities are studied (x=1,1/2,1/... Magnetism and the stability of (Ga 1-xFe x)As are investigated using the first principles LMTO-ASA band calculation by assuming supercell structures.Four concentrations of the 3d impurities are studied (x=1,1/2,1/4,and 1/8).The results show the effect of varying Fe concentration on the magnetic and stable properties. 展开更多
关键词 diluted magnetic semiconductor electronic band calculation MAGNETISM STABILITY
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Calculation model of edge carbon atoms in graphite particles for anode of lithium-ion batteries 被引量:2
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作者 张万红 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第11期2466-2475,共10页
Based on the hexagonal crystallite model of graphite,the electrochemical characteristics of carbon atoms on the edge and basal plane were proposed by analyzing graphite crystal structure and bonds of carbon atoms in d... Based on the hexagonal crystallite model of graphite,the electrochemical characteristics of carbon atoms on the edge and basal plane were proposed by analyzing graphite crystal structure and bonds of carbon atoms in different sites.A spherical close-packed model for graphite particle was developed.The fractions of surface carbon atoms(SCA) and edge carbon atoms(ECA) were derived in the expression of crystallographic parameters and particle size,and the effects of ECA on the initial irreversible capacity and the mechanisms of action were analyzed and verified.The results show that the atoms on the edge are more active for electrochemical reactions,such as electrolyte decomposition and tendency to form stable bond with other atoms and groups.For the practical graphite particle,corresponding modifying factors were introduced to revise the difference in calculating results.The revised expression is suitable for the calculation of the fractions of SCA and ECA for carbon materials such as graphite,disordered carbon and modified graphite. 展开更多
关键词 Li-ion batteries carbon anode calculation model electrochemical properties mechanism of action
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NOVEL AIRCRAFT ELECTRICAL POWER DISTRIBUTION SYSTEM BASED ON DISTRIBUTED COMPUTER 被引量:3
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作者 杨善水 付大丰 严仰光 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2001年第2期224-228,共5页
As a matured technique used in many fields,the distributed computer system is still a new management method for the aeronautical electrical power distribution system in our country. In this paper, a novel aircraft ele... As a matured technique used in many fields,the distributed computer system is still a new management method for the aeronautical electrical power distribution system in our country. In this paper, a novel aircraft electrical power distribution system based on the distributed computer system is proposed. The principles, features and structure of the aircraft electrical power distribution system and the distributed computer system named electrical load management system (ELMS) are studied. The ELMS composed of four electrical load management centers (ELMCs) and two power source processors (PSPs) operates in the 1553B buses. Principles of the ELMCs and the PSPs are introduced. With the application of the distributed computer system, the aircraft electrical power distribution system is simple, adaptable and flexible. 展开更多
关键词 aircraft electrical power supply system aircraft electrical power distribution system distributed computer system 1553B buses electrical load management system
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Adaptive Layout Partitioning for Dark Field Alternating Phase-Shift Mask Design 被引量:1
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作者 王迪 吴为民 洪先龙 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2004年第7期766-770,共5页
A new partitioning methodology is presented to accelerate 130nm and beyond large scale alternating phase shift mask(Alt PSM) design flow.This method deals with granularity self adaptively.Phas... A new partitioning methodology is presented to accelerate 130nm and beyond large scale alternating phase shift mask(Alt PSM) design flow.This method deals with granularity self adaptively.Phase conflicts resolution approaches are described and strategies guaranteeing phase compatible during layout compaction are also discussed.An efficient CAD prototype for dark field Alt PSM based on these algorithms is implemented.The experimental results on several industry layouts show that the tool can successfully cope with the rapid growth of phase conflicts with good quality and satisfy lower resource consumption with different requirements of precision and speedup. 展开更多
关键词 IC CAD phase-shift mask PARTITION phase conflict design for manufacturing
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Application of the Computer Simulation Technique to Developing EFI Engine 被引量:1
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作者 张付军 赵长禄 +2 位作者 黄英 葛蕴珊 孙业保 《Journal of Beijing Institute of Technology》 EI CAS 2000年第2期205-210,共6页
The application of computer simulation technique to electronic controlled fuel injection(EFI) engine was studied to increase the development speed and improve the overall performance of the engine and car. On the bas... The application of computer simulation technique to electronic controlled fuel injection(EFI) engine was studied to increase the development speed and improve the overall performance of the engine and car. On the basis of an EFI system developed by ourselves, the simulation model of the initial control data and engine operation points during a driving cycle and the car performance pridiction model were established. This method was applied to a mini car. The experiment showed that the simulated control data has good accuracy; and the engine test points and car performances obtained by simulation are useful for the matching of EFI system with gasoline engine and the development speed is increased. 展开更多
关键词 computer simulation electronic-controlled fuel injection (EFI) gasoline engine
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First-Principle Calculation of the Electronic Structure of Sb-Doped SrTiO_3 被引量:1
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作者 贠江妮 张志勇 +1 位作者 邓周虎 张富春 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2006年第9期1537-1542,共6页
The electronic structure,including band structure,density of states (DOS), and partial density of states of SrTi1-xSbxO3 with x = 0,0. 125,0.25,and 0.33 is calculated from the first principles of plane wave ultra-so... The electronic structure,including band structure,density of states (DOS), and partial density of states of SrTi1-xSbxO3 with x = 0,0. 125,0.25,and 0.33 is calculated from the first principles of plane wave ultra-soft pseudo-potential technology based on density function theory. The calculated results reveal that due to the electron doping,the Fermi level moves into the conduction bands for SrTi1-xSbxO3 with x = 0. 125 and the system shows metallic behavior. In addition, the DOS moves towards low energy and the optical band gap is broadened. The wide band gap and the low density of the states in the conduction band result in the transparency of the films. 展开更多
关键词 first principles SRTIO3 Sb-doping electronic structure transparent films
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Computation of Diffusion Activation Energies of C, N in γFe 被引量:2
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作者 苏文勇 张瑞林 邵彬 《Journal of Beijing Institute of Technology》 EI CAS 2002年第1期105-108,共4页
A structure relaxation model based on the empirical electron theory of solids and molecules is developed to compute the diffusion active energies of C, N in γFe. First, adding a restriction, the lattice maintains rig... A structure relaxation model based on the empirical electron theory of solids and molecules is developed to compute the diffusion active energies of C, N in γFe. First, adding a restriction, the lattice maintains rigidity when solute atom migrates to the saddle point. In this step, the hybridization classes of every atom do not change. Then, the restriction is loosed and the atoms are relaxed under the coulomb repulsive forces. It is supposed that the energy needed in the first step would be compensated partly by the second step. In this way, the diffusion active energies of C, N in γFe are computed. Compared with the experiment data, the relative errors are less than 5%, which are good results in the computation of activation energy of diffusion. 展开更多
关键词 diffusion active energy empirical electron theory electronic structure
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Finite element solution based on fast numerical technique for large-scale electromagnetic computation
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作者 赵阳 储家美 Satish Udpa 《Journal of Southeast University(English Edition)》 EI CAS 2006年第4期470-474,共5页
A numerical technique of the target-region locating (TRL) solver in conjunction with the wave-front method is presented for the application of the finite element method (FEM) for 3-D electromagnetic computation. F... A numerical technique of the target-region locating (TRL) solver in conjunction with the wave-front method is presented for the application of the finite element method (FEM) for 3-D electromagnetic computation. First, the principle of TRL technique is described. Then, the availability of TRL solver for nonlinear application is particularly discussed demonstrating that this solver can be easily used while still remaining great efficiency. The implementation on how to apply this technique in FEM based on magnetic vector potential (MVP) is also introduced. Finally, a numerical example of 3-D magnetostatic modeling using the TRL solver and FEMLAB is given. It shows that a huge computer resource can be saved by employing the new solver. 展开更多
关键词 finite element method electromagnetic computation numerical technique fast solver
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Theoretical Investigation on Photoionization and Dissociative Photoionization of Toluene
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作者 赵玉杰 詹友胜 +5 位作者 李李 李欣 连相宇 黄培 盛六四 陈军 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2017年第3期303-311,I0001,I0002,共11页
The photoionization and dissociation photoionization of toluene have been studied using quantum chemistry methods. The geometries and frequencies of the reactants, transition states and products have been performed at... The photoionization and dissociation photoionization of toluene have been studied using quantum chemistry methods. The geometries and frequencies of the reactants, transition states and products have been performed at B3LYP/6-311++G(d,p) level, and single-point energy calculations for all the stationary points were carried out at DFT calculations of the optimized structures with the G3B3 level. The ionization energies of toluene and the ap- pearance energies for major fragment ions, C7H7+, C6H5+, C5H6+, C5H5+, are determined to be 8.90, 11.15 or 11.03, 12.72, 13.69, 16.28 eV, respectively, which are all in good agree- ment with published experimental data. With the help of available published experimental data and theoretical results, four dissociative photoionization channels have been proposed: CTHT++H, C6Hs++CH3, C5H6+WC2H2, CsHs++C2H2+H. Transition structures and intermediates for those isomerization processes are determined in this work. Especially, the structures of C5H6+ and C5H5+ produced by dissociative photoionization of toluene have been defined as chain structure in this work with theoretical calculations. 展开更多
关键词 Quantum chemical calculations TOLUENE Dissociative photoionization mech-anism Density functional theory Transition states
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