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排序方式: 共有198条查询结果,搜索用时 31 毫秒
1.
A bilinear multivariate errors-in-variables model is considered. It corresponds to an overdetermined set of linear equations
AXB=C, A∈ℝm×n, B∈ℝp×q, in which the data A, B, C are perturbed by errors. The total least squares estimator is inconsistent in this case.
An adjusted least squares estimator is constructed, which converges to the true value X, as m →∞, q →∞. A small sample modification of the estimator is presented,
which is more stable for small m and q and is asymptotically equivalent to the adjusted least squares estimator. The theoretical
results are confirmed by a simulation study.
Acknowledgements. We thank two anonymous reviewers for their suggestions and corrections.? A. Kukush is supported by a postdoctoral research
fellowship of the Belgian office for Scientific, Technical and Cultural Affairs, promoting Scientific and Technical Collaboration
with Central and Eastern Europe.? S. Van Huffel is a full professor with the Katholieke Universiteit Leuven.? I. Markovsky
is a research assistant with the Katholieke Universiteit Leuven.? This paper presents research results of the Belgian Programme
on Interuniversity Poles of Attraction (IUAP V-22), initiated by the Belgian State, Prime Minister's Office – Federal Office
for Scientific, Technical and Cultural Affairs of the Concerted Research Action (GOA) projects of the Flemish Government MEFISTO-666
(Mathematical Engineering for Information and Communication Systems Technology), of the IDO/99/03 project (K.U. Leuven) “Predictive
computer models for medical classification problems using patient data and expert knowledge”, of the FWO projects G.0078.01,
G.0200.00, and G0.0270.02.? The scientific responsibility is assumed by its authors. 相似文献
2.
生物电子等排原理在新药设计中的应用 总被引:4,自引:3,他引:4
探索生物电子等排原理在新药研究中应用的规律,推动新药研究的进展;通过查阅文献资料,阐述生物电子等排的定义及各类生物电子等排的特点、使用范围、典型事例;表明生物电子等排既有外层电子总数相等的原子或基因的替换,也有在体积、形状、构象、电子分布、脂水分配系数、pKa、化学反应性(包括代谢相似性)和氢键成键能力等重要参数上存在相似性的原子或基团的替换,是对已知药物的结构改造或结构修饰;所产生新化合物优于、近于或拮抗原来药物的作用,具有成功率高、风险小、投资少的特点,在新药研究中占有重要的地位。应用生物电子等排体进行新药设计,尤其适合我国制药工业现有的实际情况。 相似文献
3.
This paper is a critical analysis of behavioral modification techniques as tools for performance enhancement in the Nigerian Banking Industry. The overriding objective of the study was to determine the impact of behavior modification techniques on performance enhancement in the Nigerian banking industry. The specific focus was on selected banks in the Makurdi metropolis, Benue State. The study employed a simple empirical survey method with a view to eliciting relevant data for analytical purpose so as to answer several questions and to obtain the objectives of the study. Both primary and secondary sources were explored in a bid to attain data which were considered to be highly germaine to the investigation under reference. Five-point Likert scale rating questionnaire was used in obtaining the views and opinions of respondents (i.e. strongly agree-5, agree-4, undecided-3, disagree-2, and strongly disagree--l). Two hypotheses were formulated and tested. Non-parametric tools including simple percentages and Pearson Chi-square statistics were used due to their analytical simplicity and relevance. The study found that banks in Makurdi utilized behavior modification strategies translated to high organizational success or enhancement in a comparative sense. This was evident from the fact that the banks net profitability trends were observed to be upwards generically. In the light of the findings of the study, it is hereby recommended that proactive behavior modifications strategies rules guideline and the like be tailored along lines with greatest organizational profitability trends and performance enhancement profiles, both potential and actual. This will require rewarding productive behaviors that detect/report fraudulent acts with cash gifts, meritawards, prizes and discouraging unproductive behaviors such as fraudulent activities, absenteeism, drug abuse, alcoholic influences and lateness to work amongst others with punishment, extinction, and negative reinforcement. 相似文献
4.
随着工作面功率的加大,矿井电压过低造成设备启动困难或不启动现象,甚至造成欠电压跳闸,因此1140V电压等级升高到3300V将是煤矿发展的前进方向。 相似文献
5.
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7.
超高分子量聚乙烯的应用及改性研究进展 总被引:7,自引:0,他引:7
介绍了超高分子量聚乙烯(UHMWPE)的性能和用途,综述了提高UHMWPE加工性能和物理性能的物理改性、化学改性、聚合物填充改性以及自增强改性方法的研究进展,指出了其今后的发展方向. 相似文献
8.
为了解决制药行业典型VOCs物质——丙酮的易挥发、难降解问题,对改性海泡石吸附丙酮的性能和表征进行了研究。研究结果表明:1)质量分数为13%的盐酸改性海泡石12h后对丙酮的吸附效果最好,吸附量达54.41 mg/g;2)水热温度170℃的海泡石对丙酮的吸附量也可达到23.20mg/g;3)对海泡石采用酸和水热改性的方式进行处理后,改性海泡石的实际丙酮平衡吸附过程均符合Lagergren二级吸附速率方程;4)表征结果表明,酸改性可使海泡石比表面积增大,杂质降低,孔道更顺畅,利于丙酮的吸附。该研究为丙酮污染的治理提出了新路线,在工业催化领域拥有广阔的应用前景。 相似文献
9.
纳米TiO_2的表面处理方法及改性效果表征 总被引:9,自引:5,他引:9
分析了纳米 TiO_2 的团聚与分散机理 ,介绍了纳米 Ti O_2 的表面处理方法及表面处理效果的表征方法。 相似文献
10.
Anna Szychta 《Management Accounting Research》2002,13(4):401
The transformation of Poland’s economic system in the 1990s as a result of transition from a centrally planned economy to a market-based system involves significant changes in the regulatory context and in accounting practice and education.This paper presents the scope of application of management accounting concepts and methods in 60 Polish enterprises covered by a questionnaire survey carried out by the author between November 1998 and December 1999 in enterprises located in central and southern Poland. The selected companies were interviewed by means of a postal survey, with inquiry forms delivered in person in some cases.The detailed analyses carried out in this paper and the conclusions presented are also based on information obtained from documentary evidence kept by the enterprises and from direct interviews conducted in the course of work in teams engaged in analysis and assessment of cost accounting practices and in management accounting system design in a number of large and medium Polish enterprises.The empirical research carried out is aimed at verification of a number of hypotheses including the following: • modification of cost accounting systems and implementation of management accounting tools in Polish enterprises is brought about by many different factors, the most important being growth of competition and ownership changes in business entities, • Polish enterprises mostly implement the methods and techniques of operational management accounting, • short-term budgeting for cost centres is the most widely used method of management accounting. 相似文献