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This article presents a list of books related to operational research. Some of the books are--"Information Theory and Coding," by Norman Abramson; "Resources and People in East Kentucky: Problems and Potentials of a Lagging Economy," by Mary Jean Bowman and W. Wakeen Haynes; "A Strategy of Decision: Policy Evaluation as a Social Force," by David Braybkooke and Charles E. Lindblom; "Introduction to Probability: A Programmed Unit in Modem Mathematics," by Earl Boyd; and "Economic Analysis and Industrial Management," by Jacques Lesourne.

The purpose of this paper is to describe the development, implementation, and availability of a computer program for generating a variety of feasible network problems together with a set of benchmarked problems derived from it. The code "NETGEN" can generate capacitated and uncapacitated transportation and minimum cost flow network problems, and assignment problems. In addition to generating structurally different classes of network problems the code permits the user to vary structural characteristics within a class. Problems benchmarked on several codes currently available are provided in this paper since NETGEN will also allow other researchers to generate identical problems. In particular, the latter part of the paper contains the solution time and objective function value of 40 assignment, transportation, and network problems varying in size from 200 nodes to 8,000 nodes and from 1,300 arcs to 35,000 arcs. [ABSTRACT FROM AUTHOR]

Cyclic queuing systems have been proposed by several authors in the study of the behavior of multiprogrammed computer systems. Programs in the system wait for service at the central processor unit (CPU); then, after page fault or input-output request at a data transmission unit (DTU), the process repeats until the program completes. Semi-Markov analysis of such systems, based on the apparently plausible assumption of independently but exponentially distributed CPU burst time, and independent, but nearly consistent DTU time may be conducted. This paper presents some very simple approximations based on a continuous-state approximation--the simple diffusion with two reflecting barriers--to describe the CPU utilization. Computational experiences from which the quality of the approximation can be assessed in reported. [ABSTRACT FROM AUTHOR]

In a variety of situations, the amount of service activity wanted by a queuer is a function of the length of time during which he has had to wait for it. Additional want of service may emerge as a consequence of his own activity. New events may induce him to change the information, which he wants to communicate to somebody else. The latter case may also be regarded as a two-phase queuing problem. This paper considers the queuing problem characterized by Poisson streams of calls for service from the customers, the intensity of the individual rate of calls, and service times, being dependent on the position of the customer. An approximate solution is given for the general case, and special cases are examined with the aid of Monte-Carlo models. The solution covers a range of `machine-interference' problems and provides a pendant, in the range of finite numbers of customers, to the classical Erlangian solution of the infinite population delay system case. The model also accounts for the well-known fact that statistics frequently indicate a longer remaining duration of a telephone conversation, the longer it has been in progress. It remains to study, how the distribution of service times affects the accuracy of the solution. [ABSTRACT FROM AUTHOR]

The automatic control of a string of high-speed, densely-packed vehicles is studied in a unified approach. Various input structures for the control schemes and their stability are studied and compared. The optimal decentralized regulation theory developed in a previous paper is applied to seek the best feedback control gains for various input structures. Value of information is defined to evaluate the relative merit of these inputs. The results can be easily applied for on-board computer designs in developing new transportation technology such as `personal rapid transit' systems. [ABSTRACT FROM AUTHOR]

Traffic signals can be synchronized so that a car, starting at one end of a street and traveling at preassigned speeds, can go to the other end without stopping for a red light. The portion of a signal cycle for which this is possible is called the bandwidth for that direction. Ordinarily the band-width in each direction is single, i.e., is not split into two or more intervals within a cycle. We solve two problems for this case: (1) Given an arbitrary number of signals along a street, a common signal period, the green and red times for each signal, and specified vehicle speeds in each direction between adjacent signals, synchronize the signals to produce bandwidths that are equal in each direction and as large as possible. (2) Adjust the synchronization to increase one bandwidth to some specified, feasible value and maintain the other as large as is then possible. The method of calculation has been programmed for a digital computer and results have been used to synchronize signals on a street in Cleveland. [ABSTRACT FROM AUTHOR]

The conditions for optimum information acquisition by means of communication systems involve two basic costs (1) average communication cost and (2) average risk cost Communication cost is determined by the values of the basic communication parameters, power, bandwidth, and time It depends on the operational conditions of message density, method of modulation, and the coding technique Risk cost is the cost of decision and arises in the detection of signals in noise It is a function of the method of decoding received signals and decreases with increasing reliability of detection Increases in power, bandwidth, and time decrease risk cost and increase communication cost, respectively Specification of the constraints existing between power, bandwidth, and time in an actual communication system permit risk cost as well as communication cost to be expressed as a function of the three communication parameters Since a trade-off exists between risk and communication costs, the optimum operating condition for a communication system can be found by solving for the minimum average total cost This method is applied to a comparative evaluation of binary communication systems using three fundamental means for acquiring information in the presence of noise unidirectional, bidirectional employing information feedback, and bidirectional employing decision feedback [ABSTRACT FROM AUTHOR]