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1.
利用2000-2014年世界投入产出表数据,使用假设抽取法测度了各国和地区对中国出口国内增加值需求的三个指标,即出口中被一国和地区直接使用的国内增加值(vaxd),出口中被一国和地区用于消费的国内增加值(vaxc)和出口中被一国和地区用于生产最终产品的国内增加值(vaxp)的区域和结构变化特征,并结合中国行业出口特征,贸易政策和参与全球价值链特征的变动对出口国内增加值需求变化特征进行了理论分析和实证分析.研究发现,在出口国内增加值的区域分布方面,发达国家的优势地位不断下降,发展中国家和新兴经济体所占份额不断上升.在结构特征方面,被一国和地区直接使用的国内增加值和被一国和地区用于消费的国内增加值在对美国、日本等主要发达国家的出口中占据较高比重,而被一国和地区用于生产最终产品的国内增加值占比很低.对变动特征进一步分析发现,先进货物行业和现代服务行业出口占比提升对出口国内增加值需求有显著的促进作用.在参与全球价值链特征方面,全球价值链相对前向参与度增长率和全球价值链相对地位增长率的提升均对三类出口国内增加值需求有显著的正向影响,其中对出口中被一国和地区用于生产最终产品的国内增加值的影响最大.  相似文献   

2.
In this study, a novel hybrid intelligent mining system integrating rough sets theory and support vector machines is developed to extract efficiently association rules from original information table for credit risk evaluation and analysis. In the proposed hybrid intelligent system, support vector machines are used as a tool to extract typical features and filter its noise, which are different from the previous studies where rough sets were only used as a preprocessor for support vector machines. Such an approach could reduce the information table and generate the final knowledge from the reduced information table by rough sets. Therefore, the proposed hybrid intelligent system overcomes the difficulty of extracting rules from a trained support vector machine classifier and possesses the robustness which is lacking for rough-set-based approaches. In addition, the effectiveness of the proposed hybrid intelligent system is illustrated with two real-world credit datasets.  相似文献   

3.
具有利益冲突的发展中国家与发达国家之间的博弈分析   总被引:2,自引:0,他引:2  
运用微分对策理论研究具有利益冲突的发展中国家与发达国家的均衡策略 .首先建立两国的动态博弈模型 ,然后利用微分对策理论分析模型的均衡解 .研究结果显示 :1 .发达国家在一定时期里的蓄意破坏是其最优策略 ;2 .发展中国家与发达国家在不同时期里各自的最优策略是不同的 ,“以牙还牙”的策略并非最优策略 ;3.发展中国家为了避免在此对策略过程中蒙受更大的损失 ,利用军事或经济的策略基本上是无效的 .发展中国家应当寻求经济、军事以外的途径 ,比如政治和谈等手段 .该文的研究方法可适用于更大范围的对策问题的研究 .  相似文献   

4.
A 3DOF (three degrees of freedom) helicopter attitude control system with multi-operation points is described as a MIMO time-varying uncertain nonlinear system with unknown constant parameters, bounded disturbance and nonlinear uncertainty, and a robust output feedback control method based on signal compensation is proposed. A controller designed by this method consists of a nominal controller and a robust compensator. The controller is linear time-invariant and can be realized easily. Robust attitude tracking property of closed-loop system is proven and experimental results show that the designed control system can guarantee high precision robust attitude control under multi-operation points. This research is supported by the National Natural Science Foundation of China under Grant Nos. 60674017 and 60736024.  相似文献   

5.
Unbounded batch scheduling with a common due window on a single machine*   总被引:2,自引:0,他引:2  
The common due window scheduling problem with batching on a single machine is dealt with to minimize the total penalty of weighted earliness and tardiness. In this paper it is assumed that a job incurs no penalty as long as it is completed within the common due window. It is the first time for the due window scheduling to be extended to this situation so that jobs can be processed in batches. An unbounded version of batch scheduling is also considered. Hence, jobs, no matter how many there are, can be processed in a batch once the machine is free. For two cases that the location of due window is either a decision variable or a given parameter, polynomial algorithms are proposed based on several optimal properties.  相似文献   

6.
7.
This paper develops a multi-year lag Input-Holding-Output (I-H-O) Model on education with exclusion of the idle capital to address the reasonable education structure in support of a sustainable development strategy in China. First, the model considers the multiyear lag of human capital because the lag time of human capital is even longer and more important than that of fixed capital. Second, it considers the idle capital resulting from the output decline in education, for example, student decrease in primary school. The new generalized Leonitief dynamic inverse is deduced to obtain a positive solution on education when output declines as well as expands. After compiling the 2000 I-H-O table on education, the authors adopt modifications-by-step method to treat nonlinear coefficients, and calculate education scale, the requirement of human capital, and education expenditure from 2005 to 2020. It is found that structural imbalance of human capital is a serious problem for Chinese economic development. This research was supporting by the Key Project of National Natural Science Foundation of China under Grant No. 60874119, Innovation Funds of Chinese Academy of Sciences, Research Fund for Humanities and Social Sciences in colleges under Grant No. 06BJY102, Key project in Jiangxi Soft Science Project under Grant No. [2006]188, Jiangxi Research Fund for Humanities and Social Sciences in colleges under Grant No. 03JJ01, and Henan Research Fund for Humanities and Social Sciences in colleges under Grant No. 2008-ZD-002.  相似文献   

8.
This paper discusses a popular community definition in complex network research in terms of the conditions under which a community is minimal, that is, the community cannot be split into several smaller communities or split and reorganized with other network elements into new communities. The result provides a base on which further optimization computation of the quantitative measure for community identification can be realized.  相似文献   

9.
The authors give an upper bound for the projective plane crossing number of a circular graph. Also, the authors prove the projective plane crossing numbers of circular graph C (8, 3) and C (9, 3) are 2 and 1, respectively.  相似文献   

10.
This paper investigates the asymptotic properties of a modified likelihood ratio statistic for testing homogeneity in bivariate normal mixture models of two samples. The asymptotic null distribution of the modified likelihood ratio statistic is found to be χ22, where χ22 is a chi-squared distribution with 2 degrees of freedom. This research was supported by the National Natural Science Foundation of China under Grant No. 10661003, SRF for ROCS, SEM under Grant No. [2004]527, and the Natural Science Foundation of Guangxi under Grant No. 0728092.  相似文献   

11.
This paper studies the impact of the reference point on a hedger's decision based upon prospect theory and experimental evidence on how prior outcomes affect risky choice. The authors show that in the futures market, a hedger who does not adjust his reference point timely would increase his positions continually as his accumulated losses increase, and finally become a speculator. Numerical simulation results under the normal distribution also lend support to the results. The model can help explain why the hedging behavior of firms turns into speculative activities and can offer some new insights into hedging behavior.  相似文献   

12.
Semivarying coefficient models are frequently used in statistical models. In this paper, under the condition that the coefficient functions possess different degrees of smoothness, a two-step method is proposed. In the case, one-step method for the smoother coefficient functions cannot be optimal. This drawback can be repaired by using the two-step estimation procedure. The asymptotic mean-squared error for the two-step procedure is obtained and is shown to achieve the optimal rate of convergence. A few simulation studies are conducted to evaluate the proposed estimation methods. This research is supported in part by the National Natural Science Foundation of China under Grant No. 10871072 and Shanxi's Natural Science Foundation of China under Grant No. 2007011014.  相似文献   

13.
Inconsistency of multi-perspective requirements specifications is a pervasive issue during the requirements process. However, managing inconsistency is not just a pure technical problem. It is always associated with a process of interactions and competitions among corresponding stakeholders. The main contribution of this paper is to present a negotiations approach to handling inconsistencies in multi-perspective software requirements. In particular, the priority of requirements relative to each perspective plays an important role in proceeding negotiation over resolving inconsistencies among different stakeholders. An algorithm of generating negotiation proposals and an approach to evaluating proposals are also presented in this paper, respectively.  相似文献   

14.
The authors define and study topological pre-image entropy for the non-autonomous discrete dynamical systems given by a sequence {fi}i=1^∞ of continuous self-maps of a compact topological space. The basic properties and the invariant with respect to equiconjugacy of pre-image entropy for the non-autonomous discrete dynamical systems are obtained.  相似文献   

15.
This paper investigates the optimal dynamic investment for an investor who maximizes constant absolute risk aversion (CARA) utility in a discrete-time market with a riskfree bond and a risky stock. The risky stock is assumed to present both the dividend risk and the price risk. With our assumptions, the dividend risk is equivalent to fundamental risk, and the price risk is equivalent to the noise trading risk. The analytical expression for the optimal investment strategy is obtained by dynamic programming. The main result in this paper highlights the importance of differentiating between noise trading risk and fundamental risk for the optimal dynamic investment.  相似文献   

16.
1. Introduction With the development of information technology and the increasing market competition, simultaneously reducing inventory costs of raw materials, work-in-process, and finished items in different stages has become a major focus for supply chain management. Industrial practice and academic research have shown that VMI (Vendor Managed Inventory) can improve supply chain performance by decreasing inventory levels and costs. VMI is a collaborative business initiative where the vend…  相似文献   

17.
This paper proposes relaxed sufficient conditions for the consensus of multi-agent systems by the averaging protocols with time-varying system topology. Bidirectional information exchange between neighboring agents is considered and both the discrete-time and continuous-time consensus protocols are studied. It is shown that the consensus is reached if there exists an unbounded time sequence such that two agents who own the maximum and minimum states at each time instant in the sequence will be jointly connected at some future time. Further, this result is applied to the original nonlinear Vicsek model, and a sufficient condition for the heading consensus of the group with restricted initial conditions is obtained.  相似文献   

18.
Energy flow drives the complex systems to evolve. The allometric scaling as the universal energy flow pattern has been found in different scales of ecological systems. It reflects the general power law relationship between flow and store. The underlying mechanisms of energy flow patterns are explained as the branching transportation networks which can be regarded as the result of systematic optimization of a biological target under constraints. Energy flows in the ecological system may be modelled by the food web model and population dynamics on the network. This paper reviews the latest progress on the energy flow patterns, explanatory models for the allometric scaling and modelling approach of flow and network evolution dynamics in ecology. Furthermore, the possibility of generalizing these flow patterns, modelling approaches to other complex systems is discussed. This research is supported by Guozhi Xu Post Doctoral Research Foundation and the National Natural Science Foundation of China under Grant No. 60574068.  相似文献   

19.
The authors propose a V N, p test statistic for testing finite-order serial correlation in a semiparametric varying coefficient partially linear errors-in-variables model. The test statistic is shown to have asymptotic normal distribution under the null hypothesis of no serial correlation. Some Monte Carlo experiments are conducted to examine the finite sample performance of the proposed V N, p test statistic. Simulation results confirm that the proposed test performs satisfactorily in estimated size and power. This research is supported by the National Natural Science Foundation of China under Grant Nos. 10871217 and 40574003; the Science and Technology Project of Chongqing Education Committee under Grant No. KJ080609; the Doctor's Start-up Research Fund under Grant No. 08-52204; and the Youth Science Research Fund of Chongqing Technology and Business University under Grant No. 0852008.  相似文献   

20.
The authors propose an affine scaling modified gradient path method in association with reduced projective Hessian and nonmonotonic interior backtracking line search techniques for solving the linear equality constrained optimization subject to bounds on variables. By employing the QR decomposition of the constraint matrix and the eigensystem decomposition of reduced projective Hes- sian matrix in the subproblem, the authors form affine scaling modified gradient curvilinear path very easily. By using interior backtracking line search technique, each iterate switches to trial step of strict interior feasibility. The global convergence and fast local superlinear/quadratical convergence rates of the proposed algorithm are established under some reasonable conditions. A nonmonotonic criterion should bring about speeding up the convergence progress in some ill-conditioned cases. The results of numerical experiments are reported to show the effectiveness of the proposed algorithm.  相似文献   

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