摘要:

AbstractIn power systems economic generation scheduling using a network loss model, it is important to evaluate the loss model coefficients with a high degree of accuracy. The size of the network model depends on the number of generation buses in the network. The loss coefficients are usually evaluated by the method of least squares from a set of load flow results of the system. Two problems are encountered in the evaluation of a large network loss model. The first is that a large number of load flow results will have to be available, a costly proposition. The second is the problem of ill-conditioning.In this paper, these two problems are addressed and remedied. A new method to evaluate the economic dispatch schedules of large power networks is presented. The proposed method uses diakoptical techniques in the evaluation of the network loss model coefficients. A practical power system is used to illustrate the method described in this paper.

ISSN:0228-6203    

DOI:10.1080/02286203.1985.11759897

出版商:Taylor&Francis    

年代:1985

数据来源: Taylor

摘要:

AbstractThis paper shows that the river water quality problem can be formulated and solved using the CSMP and DYNAMO simulation languages. In CSMP, a continuous solution approach is adopted while DYNAMO follows a finite-section solution, which assumes that water quality remains constant in each section. Application of the CSMP and DYNAMO formulations to the Hsintien River in Taiwan indicates that they can produce acceptable results as compared to available measured data, and those obtained from CSMP seem to provide a better fit.

ISSN:0228-6203    

DOI:10.1080/02286203.1985.11759898

出版商:Taylor&Francis    

年代:1985

数据来源: Taylor

摘要:

AbstractMan has long been concerned about floods and the physical and non-physical damage they bring to him and his environment. He will probably have to struggle with this damage for a long time to come, because in many parts of the world, and especially in industriali zed and densely popul ated areas, flood damage is on the increase. Because of the stochastic nature of the flood phenomenon, mathematical statistics and probability theory have come to play an increasingly important role in the study of its random behavior. Extreme value theory, in particular, has proven to be a very useful tool for the study of floods as extreme hydrologic events. several studies have been conducted within the past few years in search for a widely appl icable model for the simultaneous analysis of flood frequency and flood magnitude. Aparticular class of probabilistic space-time models, with which we are concerned in the present study, seems to be very promising, and improvements are continuously being reported in water resources literature with regard to such models. In the present report, we discuss the advantages and limitations of this probabilistic approach to flood analysis, and point to some research gaps which mathematicians and engineers may wish to investigate.

ISSN:0228-6203    

DOI:10.1080/02286203.1985.11759899

出版商:Taylor&Francis    

年代:1985

数据来源: Taylor

摘要:

AbstractSome fundamental understanding of the blow-off (i.e., the disappearance of wall shear) of a transient, laminar boundary layer by a strong cross-flow is gained by extending the classical Stokes’first problem to include blowing (and suction). It is found, by asymptotic studies as well as detailed numerical display of exact solutions for a variety of situations (including a similarity solution where the cross-flow varies inversely with the square root of time) that there are, in general, three stages clearly discernible when blowing is present: (1) pre-blow-off stage during which the influence of the eross-flow has not shown up yet; (2) blow-off stage during which the boundary layer exhibits a zero slope in its velocity profile, and the blow-off begins; and (3) post-blow-off stage during which a wave front is seen to ride with the cross-flow, carrying with it a rather rapid change of motion of the wall to the rest-state before it, while the blow-off at the wall is sustained. Furthermore, for very large Reynolds numbers, the front in the third stage becomes very sharp, and the accompanying change very sudden. In contrast, in the case of suction, the boundary layer is seen to stick to the wall, in a more exaggerated manner; and the situation approaches a steady limit for large times.

ISSN:0228-6203    

DOI:10.1080/02286203.1985.11759900

出版商:Taylor&Francis    

年代:1985

数据来源: Taylor

摘要:

AbstractUnder certain cutting conditions, due to the formation of unstable built-up edge, severe relative vibrations between the workpiece and the tool may occur. Analysis of chatter due to formation of unstable SUE requires solution of a non-linear model. In this paper the non-linear model has been analysed by simulation with the help of analog computer. It has been found that the dynamic behaviour of metal cutting with built-up edge formation is different for finish turning from that during rough turning. Some of the simulation results were verified experimentally by actual cutting.

ISSN:0228-6203    

DOI:10.1080/02286203.1985.11759901

出版商:Taylor&Francis    

年代:1985

数据来源: Taylor

ISSN:0228-6203    

DOI:10.1080/02286203.1985.11759902

出版商:Taylor&Francis    

年代:1985

数据来源: Taylor

摘要:

AbstractA dynamic stochastic optimization of the soybean market is formulated under the assumption that a representative producer and consumer maximize their expected net cash flow in a quasi-rational expectations environment. Each solves for the optimal inventory level to be held at the end of period t as a function of lagged inventories and, among other thIngs, the whole series of the current and future anticipated prices of the commodity.

ISSN:0228-6203    

DOI:10.1080/02286203.1985.11759903

出版商:Taylor&Francis    

年代:1985

数据来源: Taylor

摘要:

AbstractThis paper presents a digital simulation study of the use of a static phase shifter (SPS) as an active power controller to damp local and inter area electromechanical modes of oscillation in an integrated multimachine power system. A model is derived for incorporating static phase shifters in the integrated system state space representation. This model is utilized to investigate different control strategies to implement static phase shifters as stability enhancement tools which could replace the need for individual power system stabilizers in a multimachine power system.

ISSN:0228-6203    

DOI:10.1080/02286203.1985.11759904

出版商:Taylor&Francis    

年代:1985

数据来源: Taylor

ISSN:0228-6203    

DOI:10.1080/02286203.1985.11759905

出版商:Taylor&Francis    

年代:1985

数据来源: Taylor