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1.
With the further aggravation of international competition, the science &: technology development has already become the most important factor that it influences a country's competitiveness. This paper structures the evaluation index system of regional science and technology development. It also utilizes AHP and main component projection to analyze the current science and technology development situations of eight areas in our country and receive the final result.  相似文献   

2.
In this paper, we consider a nonautonomous competitive model with dispersion and a finite number of discrete delays. The system, which consists of two Lotka-Volterra patches, has two competitors: one can disperse between the two patches, but the other is confined to one patch and cannot disperse. Our purpose is to demonstrate that the dispersion rates have no effect on the uniform persistence of the solutions of the system. Furthermore, we establish the conditions under which the system admits a positive periodic solution which attracts all solutions.  相似文献   

3.
1 IntroductionThe control of synchronous generators is one of the most important and widely studiedproblem in the area of power systems control.Such a problem is a non-trivial one,mainlybecause of the highly nonlinear behaviour of synchronous machines.As a matter of fact,their dynamic dramatically changes when passing from a working condition to another.Asa consequence,standard PID-based controllers can not guarantee high performances overthe entire working range.Among the various control a…  相似文献   

4.
1. Introduction A strategic conflict is a situation in which two or more decision-makers are to make a decision that affects issues they have different preferences about (Fang et al. 1993). Conflicts are one of the most characteristic attributes of human societies. Various forms of strategic conflict exist all around us, in areas such as environmental management, international rela-tions, economic competition, and relationships among individuals. Conflicts are studied in a wide range of disci…  相似文献   

5.
Operating Theatre is the centre of the hospital management's efforts. It constitutes the most expensive sector with more than 10% of the intended operating budget of the hospital. To reduce the costs while maintaining a good quality of care, one of the solutions is to improve the existent planning and scheduling methods by improving the services and surgical specialty coordination or finding the best estimation of surgical case durations. The other solution is to construct an effective surgical case plan and schedule. The operating theatre planning and scheduling is the two important steps, which aim to make a surgical case programming with an objective of obtaining a realizable and efficient surgical case schedule. This paper focuses on the first step, the operating theatre planning problem. Two planning methods are introduced and compared. Real data of a Belgian university hospital "Tivoli" are used for the experiments.  相似文献   

6.
In the distribution family with common support and the one side truncated distribution family, Bickle, I. A. Ibragimov and R. Z. Hasminskii proved two important convolution theorems. As to the two-side truncated case, we also proved a convolution theorem, which plays an extraordinary role in the efficiency theory. In this paper, we will study another kind of two-side truncated distribution family, and prove a convolution result with normal form. On the basis of this convolution result, a new kind of efficiency concept is given; meanwhile, we will show that MLE is an efficient estimate in this distribution family.  相似文献   

7.
Semigroup Method for a Mathematical Model in Reliability Analysis   总被引:4,自引:0,他引:4  
1  IntroductionAn important class of systems is one where objects move squentially from one station toanother,and where they rest between stations in buffers.A transferline with a reliablemachine,an unreliable machine and a storage buffer is a typical example of such systems.This transfer line consists of two machines that separated by a storage buffer. In thistransfer line,it is assumed that workpieces( or parts) enter machine 1 from outside. Eachworkpiece isoperated firstupon in machine 1 …  相似文献   

8.
《系统管理学报》2023,(6):1348-1349
<正>Background The China Finance Review International is a flagship academic journal broadly covering the Chinese and international financial markets.The journal is founded by Antai College of Economics and Management at Shanghai Jiao Tong University,one of the top universities in Asia.  相似文献   

9.
Retail price and promotional effort are two important parameters on which demand of a commodity largely depends.This paper develops and analyzes a two-echelon supply chain where market demand depends on both retail price and sales effort.The centralized model is studied as the benchmark case,and the wholesale price-only contract is studied as the base case in which each entity tries to maximize its individual profit.Different contract mechanisms are implemented to outperform the base case in terms of both total chain’s as well as individual profits.Comparisons among the coordinating contracts are provided so that any entity may choose the better one from available contracts after the contract parameters are negotiated.The model is extensively examined through a numerical example.  相似文献   

10.
An image segmentation algorithm of the restrained fuzzy Kohonen clustering network (RFKCN) based on high- dimension fuzzy character is proposed. The algorithm includes two steps. The first step is the fuzzification of pixels in which two redundant images are built by fuzzy mean value and fuzzy median value. The second step is to construct a three-dimensional (3-D) feature vector of redundant images and their original images and cluster the feature vector through RFKCN, to realize image seg- mentation. The proposed algorithm fully takes into account not only gray distribution information of pixels, but also relevant information and fuzzy information among neighboring pixels in constructing 3- D character space. Based on the combination of competitiveness, redundancy and complementary of the information, the proposed algorithm improves the accuracy of clustering. Theoretical anal- yses and experimental results demonstrate that the proposed algorithm has a good segmentation performance.  相似文献   

11.
OPTIMAL MAINTENANCE AND REPLACEMENT OF EXTRACTION MACHINERY   总被引:1,自引:1,他引:0  
This paper considers a problem of optimal preventive maintenance and replacement schedule of equipment devoted to extracting resources from known deposits. Typical examples are oil drills, mine shovels, etc. At most one replacement of the existing machinery by a new one is allowed. The problem is formulated as an optimal control problem subject to the state constraint that the remaining deposit at any given time is nonnegative. We show that the optimal preventive maintenance, production rates, and the replacement and salvage times of the existing machinery and the new one, if required, can be obtained by solving sequentially a series of free-end-point optimal control problems. Moreover, an algorithm based on this result is developed and used to solve two illustrative examples.  相似文献   

12.
For ill-posed bilevel programming problem, the optimistic solution is always the best decision for the upper level but it is not always the best choice for both levels if the authors consider the model's satisfactory degree in application. To acquire a more satisfying solution than the optimistic one to realize the two levels' most profits, this paper considers both levels' satisfactory degree and constructs a minimization problem of the two objective functions by weighted summation. Then, using the duality gap of the lower level as the penalty function, the authors transfer these two levels problem to a single one and propose a corresponding algorithm. Finally, the authors give an example to show a more satisfying solution than the optimistic solution can be achieved by this algorithm.  相似文献   

13.
Characteristic Polynomial Assignment in 2-D System   总被引:1,自引:0,他引:1  
CONTROL THEORY AND APPLICATION1. IWTSODUCTIONTwo-dimensional (2-D) systems have mad applications such as 2-D digital Kalman filtering, image processing,etc., and have been studied extensively during the past two decades [1, 2]. The characteristic polynomialassignment problem for 2-D systems is one of the most important problems in the research of 2-D systems,and has been considered by many authors. In reference 13], the author has presellt a method for coefficielltassignmellt …  相似文献   

14.
AN IMPROVED MULTIVARIATE LOSS FUNCTION APPROACH TO OPTIMIZATION   总被引:3,自引:0,他引:3  
The basic purpose of a quality loss function is to evaluate a loss to customers in a quantitativemanner.Although there are several multivariate loss functions that have been proposed and studied inthe literature,it has room for improvement.A good multivariate loss function should represent anappropriate compromise in terms of both process economics and the correlation structure amongvarious responses.More important,it should be easily understood and implemented in practice.According to this criterion,we first introduce a pragmatic dimensionless multivariate loss functionproposed by Artiles-Leon,then we improve the multivariate loss function in two respects:one ismaking it suitable for all three types of quality characteristics;the other is considering correlationstructure among the various responses,which makes the improved multivariate loss function moreadequate in the real world.On the bases of these,an example from industrial practice is provided tocompare our improved method with other methods,and la  相似文献   

15.
This paper further investigates cluster synchronization in a complex dynamical network with two-cluster. Each cluster contains a number of identical dynamical systems, however, the subsystems composing the two clusters can be different, i.e., the individual dynamical system in one cluster can differ from that in the other cluster. Complete synchronization within each cluster is possible only if each node from one cluster receives the same input from nodes in other cluster. In this case, the stability condition of one-cluster synchronization is known to contain two terms: the first accounts for the contribution of the inner-cluster coupling structure while the second is simply an extra linear term, which can be deduced by the "same-input" condition. Applying the connection graph stability method, the authors obtain an upper bound of input strength for one cluster if the first account is known, by which the synchronizability of cluster can be scaled. For different clusters, there are different upper bound of input strength by virtue of different dynamics and the corresponding cluster structure. Moreover, two illustrative examples are presented and the numerical simulations coincide with the theoretical analysis.  相似文献   

16.
Structuring the hierarchy of a system is an important link of solving problems with the analytic hierarchy process. This paper gives and proves the two theorems about the relationship between the hierarchy and the reachability matrix of the system. On the basis of it, we propose a method of structuring hierarchy by directly using the reachability matrix of the system. This method is simpler and clearer than that of interpretive structural modeling and is suitable for both manual calculating and computer proceeding. It fully shows the simplicity of the AHP.  相似文献   

17.
LOGISTICS SCHEDULING: ANALYSIS OFTWO-STAGE PROBLEMS   总被引:4,自引:0,他引:4  
This paper studies the coordination effects between stages for scheduling problems where decision-making is a two-stage process. Two stages are considered as one system. The system can be a supply chain that links two stages, one stage representing a manufacturer; and the other, a distributor It also can represent a single manufacturer, while each stage represents a different department responsible for a part of operations. A problem that jointly considers both stages in order to achieve ideal overall system performance is defined as a system problem. In practice, at times, it might not be feasible for the two stages to make coordinated decisions due to (i) the lack of channels that allow decision makers at the two stages to cooperate, and/or (ii) the optimal solution to the system problem is too difficult (or costly) to achieve.Two practical approaches are applied to solve a variant of two-stage logistic scheduling problems. The Forward Approach is defined as a solution procedure by which the first sta  相似文献   

18.
During the COVID-19 pandemic, the international financial markets experienced severe turbulence. Under the background of “Made in China 2025”, substantial entity enterprises have a large demand for non-ferrous metals. With the enhancement of financial attributes of non-ferrous metals, it is vital to prevent financial systemic risk contagion in the non-ferrous metal markets. In this article,the ensemble empirical mode decomposition method is used to decompose the prices of eight important non-fer...  相似文献   

19.
Abstract Accurate forecast of future container throughput of a port is very important for its con struction, upgrading, and operation management. This study proposes a transfer forecasting model guided by discrete particle swarm optimization algorithm (TF-DPSO). It firstly transfers some related time series in source domain to assist in modeling the target time series by transfer learning technique, and then constructs the forecasting model by a pattern matching method called analog complexing. Finally, the discrete particle swarm optimization algorithm is introduced to find the optimal match between the two important parameters in TF-DPSO. The container throughput time series of two im portant ports in China, Shanghai Port and Ningbo Port are used for empirical analysis, and the results show the effectiveness of the proposed model.  相似文献   

20.
正Background The China Finance Review International is a flagship English academic journal broadly covering the Chinese and international financial markets.The journal is founded by Antai College of Economics and Management at Shanghai Jiao Tong University,one of the top universities in Asia.The journal publishes quality empirical and theoretical research on financial and economic issues.  相似文献   

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