bluuebunny/crossref_metadata_2025 huggingface dataset:
Letter to the Editor—A New Application of Operations Research
Authors: Greenberg Irwin
Published: November 2008

The law enforcement agencies of the federal, state, and local governments are no strangers to the attributes of science. From the applications of the physical sciences in the police laboratories to the use of trained behavioral scientists, the scientific method plays a large part in law enforcement. However, with the possible exception of certain electronic data processing systems, the fields of operations research and systems engineering have been overlooked.
Letter to the Editor—Comments on a Paper by Shakun
Authors: Davis Gordon B.
Published: November 2008

The following are comments on “Application of Operations Research to Complex Financial Agreements—A Profit-Sharing Illustration,” by Melvin E. Shakun, which appeared in Operations Research, volume 8, pages 65–81 (January–February, 1960).
Uncertainties in Operations Research
Authors: Hitch Charles
Published: November 2008

What I want to do this evening is to talk in a general, but I hope constructive, way about some of operations-research's most intractable problems—those associated with uncertainties, and especially with those uncertainties tinged with ‘game’ elements. My own operations-research experience is pretty much restricted to military problems but, for an examination of the implications of uncertainty, this doesn't seem to me to be too important. For the kinds of uncertainties that we encounter in military problems have their counterparts and analogs in business and in everyday life (Address of the Retiring President, Operations Research Society of America, Seventeenth National Meeting, New York, May 19, 1960.).
Optimum Search Routines for Automatic Fault Location
Authors: Firstman Sidney I. , Glues Brian
Published: November 2008

This paper comprises an extension of Model I of a recent paper of Gluss, (1959) Opns. Res. 7, 468–477, and its purpose is to dictate strategies that minimize the expected cost (in time) of locating a fault in a complex system of equipment. These strategies are specialized for use with automatic testing equipment The model assumes that the complex system consists of N modules containing n(1), …, n(N) elements respectively, that the cost of examining the modules are t1, …, tN respectively, and that the costs of examining the elements within the rth module are tr1, …, trn(r). It is further assumed that module tests are performed to find which module is faulty before element tests are performed, and that there exist probabilities at each stage that errors of two kinds can be made (1) that the test fails to detect an actual fault in the module or item tested, (2) that the test finds a fault that does not exist. The estimation of the probabilities of faults lying in respective modules or elements is performed in a different way from that in Gluss' paper they are computed from element reliability data by manipulation of their λ parameters, where λ is the element failure rate. Furthermore, consideration is given to fault symptoms that are supplied by weighting the probabilities according to the symptom information. Because of the anticipated difficulty in obtaining the necessary parameter estimates, the analysis may be most useful for its illumination of the influence the several required estimates have on the optimum search routine.
The Control of Traffic Flow to Increase the Flow
Authors: Greenberg Harold , Daou Arthur
Published: November 2008

An operational study of tunnel-traffic flow is presented. A bottleneck within the tunnel is shown to cause shock waves which travel backward in the stream and continue to the entrance of the tunnel. Flow and density data at the bottleneck is fitted to a fluid model description of the flow. Analysis of the speeds of successive vehicles indicate that the speeds stabilize to where the resultant flow is below the maximum allowable flow at the bottleneck. This speed is such that shock waves develop. The control of the traffic input by platooning the entering vehicles is shown to eliminate the shock waves and allow higher flows.
Letter to the Editor—A Classroom Example of Linear Programming (Lesson Number 2)
Authors: Jewell William S.
Published: November 2008

Georges Brigham's discussion (Georges Brigham, “A Classroom Example of Linear Programming” (Letter to the Editor), Opns Res. 7, 524–533 (1959)) of the application of linear programming to the problem of blending feed illustrates the use, rather than the abuse, of optimization theory to find a practical answer. With your permission, this author would like to present some similar experiments in solving feed blending problems, indicating some traps for the unwary novice and pointing out some uses of the dual solution.
Letter to the Editor—Comments on the Growth of Research and Development Expenditures
Authors: Horowitz Ira
Published: November 2008

This is a portion of a longer paper presented at the Sixteenth National Meeting of the Operations Research Society of America, November 11–13, 1959, in Pasadena, California.
The Optimum Solution in Operations Research
Authors: Ornea J. C. , Stillson Paul
Published: November 2008

The concept of an “optimum” solution is defined in terms of the objective of an operations-research effort. An operational, technological, and investment objective is discussed and three separate formulations for a typical problem in the petroleum industry are developed in accordance with each approach.
A Simple Queue with Several Preemptive Priority Classes
Authors: Heathcote C. R.
Published: November 2008

Customers of a single server negative exponential queue are divided into R preemptive priority classes. The difference equations for the steady state probabilities are solved by the method of generating functions. The similarity between these and the equations for the Laplace transforms of the temporal probabilities is noted. This enables the Laplace transform of the temporal generating function to be derived in a simple way from the steady state solution. Inverse transformations are carried out in a few particular cases. Explicit results are given only for the special case when all service rates are equal. The general case requires only additional calculation, the method being the same.
Minimization of a Piecewise Quadratic Function Arising in Production Scheduling
Authors: Wilde Douglass J. , Acrivos Andreas
Published: November 2008

In the study of production scheduling to meet random fluctuations in supply and demand, a probabilistic measure of effectiveness can be used. This measure is a piecewise quadratic positive definite function having discontinuous derivatives at a finite number of points. The unique minimum of this function, which always exists, can be found by applying an algorithm resembling the simplex algorithm. The computations per iteration are longer and the logic more complicated than for the simplex algorithm. The method can be applied to any overdetermined system in which all of the critical variables are functions of a single adjustable variable. The system is assumed to be linear and the input disturbances are presumed Gaussian.
Letter to the Editor—Queues with “Exponential-Type” Service-Time Distributions
Authors: Healy Thomas L.
Published: November 2008

This letter describes the use of the expected number of units in the system (i.e., queue plus service facility) as a criterion to determine under what conditions a k-Erlang or hyper-exponential service-time distribution provides a better model than the negative exponential distribution. The models to be considered are those for a single service facility with Poisson distributed arrivals under steady-state conditions and with infinite queues permitted.
Letter to the Editor—An Approach to the Ship-Collision Problem
Authors: Kyrala A.
Published: November 2008

The individual ship-collision problem consists of the determination of a (curvilinear or polygonal) course that will avoid collision with any other ship and still arrive at a desired port, or approach a desired limiting course direction. The collective ship-collision problem consists of the determination of such courses for all of a given set of ships. This note will discuss only the former.
A Boltzmann-Like Approach for Traffic Flow
Authors: Prigogine I. , Andrews F. C.
Published: November 2008

The approach to the traffic-flow problem based on an integral differential equation of the Boltzmann type which has been considered by one of us (I P ) in a recent paper is further developed. The possibility of passing is explicitly introduced into the equation for the velocity distribution function. As in the previous paper, it is shown that at sufficiently high concentration a collective flow process must take place. In order to study more specifically the effects of one car on another, we define reduced n-car distribution functions giving the probability of finding a cluster of n cars all having the same velocity. We derive an equation for the evolution of this distribution function. Study of it yields some information as to the way traffic changes from relatively free flow to completely hindered, “condensed” flow.
Letter to the Editor—Comments on Two Charts
Authors: Doeh Giyora
Published: November 2008

In Andrew Vazsonyi's “Comments on a Paper by Karush,” appearing in the May–June 1960 issue of Operations Research, a chart is presented which depicts in graphical form the quotient of the discrete probability distribution divided by the cumulative probability distribution (Poisson). This is the same as the chart in my Letter, “A Graphical Tool for the No-Queue Model,” published in the January–February 1960 issue.
Letter to the Editor—The Shortest-Route Problem
Authors: Peart Robert M. , Randolph Paul H. , Bartlett T. E.
Published: November 2008

This letter is a supplement to the excellent review of solutions of the shortest-route problem by Pollack and Wiebenson [Pollack, M., W. Wiebenson. 1960. Solutions of the shortest-route problem—A review. Opns. Res. 8 224–230.] in the March–April, 1960 issue of Operations Research. Four additional solutions are presented, two of which are linear programming methods related to Dantzig's tree method [Dantzig, G. B. 1957. Discrete-variable extremum problems. Opns. Res. 5 266–277.] mentioned in the article.
Customer Behavior As a Markov Process
Authors: Herniter Jerome D. , Magee John F.
Published: November 2008

Simple Markov processes appear to provide a fruitful conceptual basis for study of customer populations in the face of marketing activity. The purpose of this paper is to summarize characteristics and some implications and applications of the Markov model. Characteristic behavior of the model is compared with published data, and areas for further analytical and experimental effort are indicated.
Letter to the Editor—Comment on the “Reliability of Aircraft Structures in Resisting Chance Failure”
Authors: Bogdanoff J. L. , Kozin F.
Published: November 2008

The purpose of this brief paper is to point out an objection to the assumptions made in a recently published formula on the reliability of an aircraft in resisting chance failure, and to indicate how, with first passage time probabilities, it is possible to derive a more realistic expression for this formula.
Letter to the Editor—Initial Provisioning with Confidence
Authors: Barnett Howard H.
Published: November 2008

The paper in its present form describes briefly the use of the exponential model for failure distribution to obtain, under certain conditions, the number of items of one type to supply at the start of an operation that consumes the items as a result of their failure. One condition is the confidence α that complete consumption will not occur before completion of the operation.
Errata
Authors: Pollack Maurice
Published: November 2008

List of editorial errors in the author's Letter to the Editor, “The Maximum Capacity Through a Network,” Operations Research, Vol. 8, 733–736, September–October 1960.
Strategic Reliability and Preventive Maintenance
Authors: Truelove Alan J.
Published: November 2008

Strategic reliability is defined as the product of availability, and the reliability over a fixed period of time x Preventive maintenance is performed after Tp hours of continuing operation without failure. We have to choose Tp so as to optimize, in case (i), the availability, and in case (ii), the strategic reliability. The exact solution for (i) was given by Morse and is briefly summarized. The exact solution for (ii) is derived. An approximate solution for (ii) is derived, and it is shown that the “optimum curve” commonly drawn for (i) may be used to solve (ii) approximately.
Approximate Expected Delays for Several Maneuvers by a Driver in Poisson Traffic
Authors: Little John D. C.
Published: November 2008

Models are given for calculating the expected delay to a driver in making several maneuvers at or near a traffic light. These include going straight through, turning left, and various entrances and exits from the traffic stream. Traffic approaching the intersection is assumed to be Poisson. Approximations are used that apply at medium and low traffic flows.
A Class of Stochastic Investment Problems
Authors: Fisher James L.
Published: November 2008

A decision maker, faced with investment opportunities that occur throughout time, must, when confronted with a particular investment, decide whether to accept the investment. The problem of determining optimal decision rules under these conditions is formulated as a stochastic process that can be analyzed by the functional equation of dynamic programming. Some simple investment problems involving a decision maker with fixed assets are formulated and for a specific example, solved numerically. As an extension of these simple situations, a problem based on a business application of investing a stream of assets is solved and optimal decision rules are presented.
Optimum Weapon Deployment for Nuclear Attack
Authors: Perkins F. M.
Published: November 2008

Presented herein are solutions for the optimum deployment of both offensive and defensive weapons for a nuclear missile or aircraft attack against point targets. These solutions make it possible to determine rapidly the optimum deployment for both offense and defense and to estimate the expected level of destruction. The equations give some insight as to the interrelations between such factors as surviving worth, target hardness, warhead yield, accuracy, and defensive and offensive vehicle inventories.
On Lagrange Multipliers and Inequalities
Authors: Dorn W. S.
Published: November 2008

Necessary and sufficient conditions for minima (maxima) of nonlinear functionals subjected to linear constraints are derived. Two classes of functionals are considered (a) convex (concave) functionals for which necessary and sufficient conditions for global minima (maxima) are obtained, and (b) more general functionals possessing continuous second derivatives for which necessary and sufficient conditions for local optima are obtained. In the first case the theorems presented here are special cases of the well-known Kuhn-Tucker theorems. Some simple examples are included.
Comments on the Preceding Paper
Authors: Fiacco Anthony V.
Published: November 2008

A solution to the problem of acquiring an acceptable starting point is given in “A General Method for Nonlinear Programming,” by Anthony V. Fiacco, Nicholas M. Smith, and David Blackwell (Bulletin of the Operations Research Society of America, Volume 8, Supplement 1, page B-36 (1960). This the paper referred to in reference 17 of the Carroll, C. W. 1961. The created response surface technique for optimizing nonlinear, restrained systems. Oper. Res. 9 169–183.
Full-Service Probability for Regular Arrangements
Authors: Marshall Clifford W.
Published: November 2008

A regular arrangement is a multiple correspondence between a set of elements supplying a service, called stations, and a set of elements requiring service, called installations. There are n installations and 2n stations. The regular arrangement is such that stations aj and an+j are able to supply service to installations bj and bj+1. Each station therefore can service either of two installations and each installation is associated with four stations. It is supposed that after this arrangement has been made a random event removes some stations. The remaining stations are used in the best possible way to supply service to the installations, a station being able to serve only one of its associated installations. The present paper obtains the probability that after the random event it is possible for all installations to receive service.
Critical-Path Planning and Scheduling: Mathematical Basis
Authors: Kelley James E.
Published: November 2008

This paper is concerned with establishing the mathematical basis of the Critical-Path Method—a new tool for planning, scheduling, and coordinating complex engineering-type projects. The essential ingredient of the technique is a mathematical model that incorporates sequence information, durations, and costs for each component of the project. It is a special parametric linear program that, via the primal-dual algorithm, may be solved efficiently by network flow methods. Analysis of the solutions of the model enables operating personnel to answer questions concerning labor needs, budget requirements, procurement and design limitations, the effects of delays, and communication difficulties.
Activity Subdivision and PERT Probability Statements
Authors: Healy Thomas L.
Published: November 2008

The Program Evaluation and Review Technique (PERT) has been developed and implemented as a technique for planning and evaluating the progress of research and development programs. Probability theory is used in PERT to calculate a measure of the uncertainty in meeting scheduled dates. These computed probabilities can then be used by managers to aid their judgment in evaluating the validity of schedules for accomplishing program objectives. This paper investigates the effect of subdividing activities in PERT flow diagrams on computed probabilities for meeting scheduled dates. It is shown that the mechanics of activity subdivision can increase or decrease the computed probabilities, depending upon whether the scheduled date for an event is later or earlier in time than the expected date. Management personnel who are using PERT probabilities to aid their judgment in evaluating schedules should be aware of the potential biases inherent in the computation of probabilities.
Probability Functions for Waiting Times in Single-Channel Queues, with Emphasis on Simple Approximations
Authors: Saunders L. R.
Published: November 2008

One approach to the waiting-time problem is through the integral equation, whose solution is the cumulative probability function—the method derived by Lindley. The equation is of the type for which a general solution was developed by Wiener and Hopf, and an adaptation of their method is presented in this paper. A quite wide range of arrival and service-time distributions can be accommodated, and approximations for the tail of the density curve are readily found. This is a convenient property, because the useful information about waiting times is fully provided by the mean value and the tail of the curve. The approximation process occurs within the solution, giving a reduction in the total mathematical labor compared with the forming of an approximation from an exact final formula.
Application of Dynamic Programming to Countercurrent Flow Processes
Authors: Dranoff J. S. , Mitten L. G. , Stevens W. F. , Wanninger L. A.
Published: November 2008

This paper shows how the methods of dynamic programming may be applied to the problem of optimal design and operation of countercurrent flow processes. The physical relations involved are summarized by a set of transformations describing the technology of the process. The dynamic programming recursive maximum return functions are then used to generate a set of optimal technologies. The stages above and below the feed stage are treated as independent dynamic programming problems that are then coupled through the feed stage technology. The optimal design of a complex of chemical plants is used as an illustrative example.
Letter to the Editor—Useful Properties of the Poisson Distribution
Authors: Hadley G. , Whitin T. M.
Published: November 2008

Presented below is a table of properties of the Poisson distribution that have been found useful in working with a variety of operational models.
Letter to the Editor—Addendum to “Operations Research for the U. S. Navy Since World War II”
Authors: Engel Joseph H.
Published: November 2008

With the passage of time since October 1958, when the talk “Operations Research for the U.S. Navy Since World War II” was given, there have been considerable changes in the Operations Evaluation Group. The purpose of this addendum is to inform the members of the Society of two of the most significant additions to the operation and constitution of OEG since the time this talk was given.
Letter to the Editor—Comments on “The Shortest-Route Problem” by Peart, Randolph, and Bartlett
Authors: Pollack Maurice , Wiebenson Walter
Published: November 2008

Peart, Randolph, and Bartlett (Peart, R. M., P. H. Randolph, T. E. Bartlett. 1960. The shortest-route problem. Opns Res. 8 866–868.) contribute four additional methods for solving the shortest-route problem which provide a valuable supplement to our review article (Pollack, M., W. Wiebenson. 1960. Solutions of the shortest-route problem—a review. Opns Res. 8 224–230.). The fourth method, however, includes contradictory statements concerning its application.
Letter to the Editor—Comments Suggested by Schelling's Paper
Authors: Brooks Douglas L.
Published: November 2008

Dr Schelling's paper (Schelling, T. C. 1961. Dispersal, deterrence, and damage. Oper. Res. 9 363–370.) admirably serves his purpose in calling attention to two important issues, the specific one of SAC bomber dispersal and the more general one of strategic alternatives to sheer blind destructiveness in a possible future U.S.-U.S.S.R. war.
Production Smoothing and Inventory Control
Authors: Beckmann Martin J.
Published: November 2008

Let production of a product be continuous and subject to the following costs the direct cost of production is proportional to the rate of output, the cost of changing the rate is proportional to the size of the change, with (possibly) different coefficients for upward and downward shifts, the cost of storage is proportional to the stock level, and there is a proportional penalty for backlogs. No orders are lost demands for the product arise at random intervals and the number of units demanded is a random variable with known distribution. The problem is to find the optimal policy of adjusting the rate of production to stock. It is shown that there exists a zone of control depending on the stock level such that no adjustment is made as long as the rate of production falls inside this zone and the rate is brought to its nearest endpoint when it has fallen outside the zone. A discrete version of this problem has been programmed on the IBM 650 Results of some computations are presented.
Optimizing Systems When Components Have Discontinuous Cost Functions
Authors: Peart Robert M. , French Charles E. , Isaacs G. W.
Published: November 2008

A special type of problem can be solved by linear programming even though some of the cost functions are discontinuous at zero due to fixed charges. A group of systems is represented on a flow chart, a network of directed links. Any single path through the network represents a complete system. The minimum-cost single path is the desired solution. Associated with each link are certain machines and known operating costs which apply if that link is in the system. A certain machine may be specified in several links, and a given system may use such a “multiple-use” machine once, several times, or not at all. This fact prohibits the use of a link cost that is constant regardless of the rest of the system. The types of restriction equations are limited, and the simplex algorithm normally yields a solution of the form xı = 0 or 1. The use of integer-solution methods allows further restrictions to be added Problems of determining optimum production levels and the materials handling system for this production can be solved.
Stability of Following in Two Dimensions
Authors: Tuck Ernest
Published: November 2008

The mechanism by which objects follow each other on a two-dimensional surface is considered, with the movement of a convoy of ships in mind as a physical example. This is to be compared with single-lane traffic dynamics, which is essentially a one-dimensional following theory applied to cars on a straight highway. At first the assumed laws of following are linear in the position and velocity vectors of the ships, and the form of relation used is one suggested partly by previous work on traffic dynamics and partly from the theory of guided missiles. As a measure of imperfections in speed control and steering, various types of time constants are introduced and the resulting equations tested for stability, yielding criteria for the maximum permissible size of the time constants. Nonlinear control equations are also investigated, and by making linear approximations to the trajectories in these cases, stability criteria are again suggested. Finally a few computed trajectories have been obtained, including an interesting example where the following ship suddenly reverses its direction of motion in course.
Analytical Methods for Determination of Training-Device Requirements
Authors: Yarnold Kenneth W. , Nehnevajsa Jiri
Published: November 2008

Training devices must be conceived of some time after the conceptualization of the systems they simulate. They must be delivered earlier than the systems they simulate. They compete for development funds with the system itself and with one another. There is thus a need for a logical analytical tool, which can operate upon the guesses and assumptions that, early in system development, are all that are available, in order to generate training-device needs, priorities, values, and specifications. This paper describes the development of such a logical tool. The process developed has been used to develop training device requirements for a large number of varied military systems. Though its results are sensitive to the assumptions with which it is entered, the method does provide a clearer statement of the training devices that will be needed than other methods appear to do.
Letter to the Editor—An Application of the Assignment Problem
Authors: Machol Robert E.
Published: November 2008

The famous physician who discovered a cure for which there was no known disease has his parallel in many OR discoveries of solutions for which there is no known problem. Outstanding among these is the assignment problem. Mathematically, the assignment model can be represented as a linear-programming model in which each coefficient in every constraint equation is zero or unity. It provides a particularly attractive introduction for students to linear programming because the model is so simple, and because the Hungarian method (Flood, Merrill M. 1956. The traveling-salesman problem. Opns Res. 4 61–72.) provides such elegant solutions.
Errata
Authors: Jewell William S.
Published: November 2008

Corrections to the author's article “The Properties of Recurrent Event Processes” which appeared in Operations Research 8 446–472 (July–August 1960).
Operating Characteristics of a Simple Production, Inventory-Control Model
Authors: Gaver D. P.
Published: November 2008

Queuing theory is adapted to study the coordination of a continuous-level production rate with a base-stock level inventory policy, where the latter is depleted by a particular random demand process. Figures of merit for the combined production, inventory system (such as stock-out probability and expected demand delay, average inventory level, and production idleness probability) are given in terms of demand parameters, production rate, and maximum stock level. Costs are discussed, and a criteria is given for deciding when the stocking of inventory is economically desirable. Improvements in the model are proposed.
Driver Response to the Amber Phase of Traffic Signals
Authors: Olson Paul L. , Rothery Richard W.
Published: November 2008

Observations of motorist response to the amber phase of traffic signals obtained at five intersections, representing three speed zones, are presented. The data from these observations give an estimate of the probability of stopping for vehicles as a function of their distance from the intersection at the onset of the amber phase of the traffic signal. The results lend no support to a popular hypothesis, i.e., that drivers tend to “take advantage” of a long amber phase by treating it as an extension of the green. The results of the study are compared with other investigations pertaining to amber phase lengths and implications of this work for the design of amber phases is discussed.
Preemptive Resume Priority Queue
Authors: Jaiswal N. K.
Published: November 2008

The queue length probability generating function for a preemptive resume priority queue characterized by Poisson arrivals and general service time distributions has been obtained by using the “supplemetary vanable method”. The preempted item follows the “resume” rule so that upon re-entry the service on the nonpriority unit is started at the point where it was interrupted when preemption occurred. Apart from the steady-state solution, the Laplace transform of the time dependent probability generating function and the length of busy periods has also been obtained.
Letter to the Editor—A Note on “Statistical Equilibrium”
Authors: Morris Robert , Wolman Eric
Published: November 2008

In most expositions of steady-state queuing theory in which the system can be represented as a Markov process, the condition of “statistical equilibrium” is introduced into the mathematical model for the queue by assuming that the mean transition rate into any given state is equal to the mean transition rate out of that state. The authors have found a slightly different approach that offers deeper insight into the relation between the queue and its model, and sometimes a reduction in the amount of algebraic manipulation required to find the distribution of queue lengths.
Letter to the Editor—A Doubled-Ended Queuing Problem of Kendall
Authors: Dobbie James M.
Published: November 2008

The distribution of the difference between two independent Poisson variables has been obtained by Irwin (Irwin, J. O. 1937. The frequency-distribution of the difference between two independent variates following the same Poisson distribution. J. Roy. Stat. Soc. 100(Part 3) 415–416.), when the means are equal, and by Skellam (Skellam, J. G. 1946. The frequency-distribution of the difference between two Poisson variates belonging to different populations. J. Roy. Stat. Soc. 109(Part 3) 296.), when the means are unequal. The purpose of this note is to point out that the Irwin-Skellam distribution still applies when α and β are time-dependent.
Inclusion of Detection in Probability of Survival Models
Authors: Dubins Lester E. , Morgenthaler George W.
Published: November 2008

The chance for survival in aerial or vehicle-to-vehicle space combat, particularly with guided missiles, would seem to depend in large measure upon the relative ability to detect. But there seems to be few published quantitative studies of how the chance of survival varies with ability to detect. Therefore, this note develops simple models for estimating survival that include the detection distributions of the combatants. Simplifying assumptions are suggested that are realistic and mathematically reasonable, and it is indicated how “answers” can be computed in a variety of cases.
Bargaining Strategy in a Production and Distribution Problem
Authors: Chacko George K.
Published: November 2008

An attempt is made to select a bargaining strategy for a multiplant, multi-product, manufacturing company, engaged in negotiations with two of its distributors. The basis for negotiations is the company's net profit equivalent, and the distributors' net profit. Net profit is excess of income over expenditure. Net profit equivalent is net sales minus variable cost, statistically determined from 52-month data, treating output of the two component groups of products as the independent variable, and their cost, the dependent variable. The company's decision to manufacture in three, instead of four, plants affects the three types of revenue earned by the distributors. How should the company act vis-à-vis its distributors? The company may enter into coalitions with the customers of the distributors, and bid to supplant the distributors. It may negotiate with other manufacturing companies to supply the distributor customers, thus saving warehousing costs. So can the customers collude among themselves, with other manufacturing companies, etc. These coalitions, simultaneously entered into by the same players, who band together for and against the same party at the same time, in order to achieve joint-profit maximization in a nonzero-sum game, are defined for the first time in this paper as concomitant coalitions. The influence of the power to “bind” of the weaker players, who improve their gains by “some voluntary, but irreversible freedom of choice” is examined in the imputations. The dominant strategies are identified by inspection, and the corresponding outcome for the different players worked out has intutive appeal. Accepted by the company management as pertinent to long-term implementation, this analysis demonstrated how an otherwise loss situation could be successfully turned into one of significant profit.
A Linear Programming Approach to the Cutting-Stock Problem
Authors: Gilmore P. C. , Gomory R. E.
Published: November 2008

The cutting-stock problem is the problem of filling an order at minimum cost for specified numbers of lengths of material to be cut from given stock lengths of given cost. When expressed as an integer programming problem the large number of variables involved generally makes computation infeasible. This same difficulty persists when only an approximate solution is being sought by linear programming. In this paper, a technique is described for overcoming the difficulty in the linear programming formulation of the problem. The technique enables one to compute always with a matrix which has no more columns than it has rows.
The Face of Bargaining
Authors: Deutsch Morton
Published: November 2008

The nature of a bargaining situation is discussed. Two general propositions about the conditions affecting the likelihood of a bargaining agreement are presented. The effects of the availability of threat and of permissive and compulsory communication upon interpersonal bargaining are investigated experimentally in a two-person bargaining game. The major findings are (1) Under conditions of bilateral (i.e., available to both players) threat, players have most difficulty in reaching agreements, unilateral (available to one player) threat produces somewhat less difficulty, however, only under conditions of no threat are subjects able to maximize their payoffs. (2) Under conditions of permissive communication, subjects' performance does not differ from that found when the opportunity to communicate is not present. (3) Under conditions of compulsory communication, an improvement in performance is noted in the unilateral threat condition only. These findings are discussed with respect to the balance of cooperative and competitive motivational forces present and the player's need to maintain “face” in interpersonal encounters.
Letter to the Editor—The Maximum Capacity Route Problem
Authors: Hu T. C.
Published: November 2008

We consider the problem of finding maximum capacity routes between all pairs of nodes in a network.
Letter to the Editor—Some Properties of a Disguised Poisson Function
Authors: Benson F. , Gregory G.
Published: November 2008

There have been a number of papers on closed queues in which the solution has been stated in the form of formulas for the probabilities of each state in terms of one particular state probability. However, the measures of effectiveness proposed are usually linear functions of the state probabilities and it is often possible to compute these more efficiently without calculating the individual state probabilities explicitly.
Letter to the Editor—Comments on a Paper by Thomas Healy
Authors: Roseboom John H.
Published: November 2008

In the May–June issue of Operations Research, Thomas Healy presents findings which he uses to demonstrate that a prescribed subdivision of activities will change probabilities in a PERT network analysis [“Activity Subdivision and PERT Probability Statements,” 9 341–347 (1961)].

As a member of the original PERT team, I would like to call attention to and take issue with some aspects of his paper.
Puberty in a case with novel 17-hydroxylase mutation and the putative role of estrogen in development of pubic hair
Authors: Turan Serap , Bereket Abdullah , Guran Tulay , Akcay Teoman , Papari-Zareei Mahboubeh , Auchus Richard J
Published: November 2008

Objective

17-Hydroxylase/17,20-lyase deficiency (17OHD) results from mutations in the CYP17A1 gene, leading to failure to synthesize cortisol, adrenal androgens, and gonadal steroids. Adrenarche is a consequence of the increased production of adrenal androgens. Here, we report a case carrying novel R239Q mutation causing complete functional loss of CYP17A1, and thus absence of adrenal and gonadal sex hormone production. The patient has had unexpected pubic hair development and insufficient breast development with estrogen replacement therapy. Possible mechanisms leading to pubic hair development and breast underdevelopment are discussed.

Patient and methods

A 15-year-old female born to consanguineous parents presented with the lack of full breast development and irregular menses after the age of 14 years. She had Tanner III breast development on one side, Tanner I on the other side and Tanner I pubic hair and, no axillary hair development. The serum levels of FSH, LH, and progesterone were high and, estradiol was low. The measurement of basal and ACTH-stimulated steroids was consistent with the diagnosis of 17OHD. Genetic analysis revealed novel homozygous mutation R239Q in CYP17A1 gene. Therapy with hydrocortisone was initiated and followed by the addition of conjugated estrogen. Her breast development did not improve considerably, however, pubic hair development started after estrogen treatment in spite of undetectable serum levels of androgens.

Conclusion

This case study suggests that estrogen exerts a permissive effect on pubic hair development in girls, even in the presence of very low-circulating androgens, and impaired breast development might be due to estrogen/progesterone imbalance in breast tissue.
Osteopontin Combined with CD44, a Novel Prognostic Biomarker for Patients with Hepatocellular Carcinoma Undergoing Curative Resection
Authors: Yang Guo-Huan , Fan Jia , Xu Yang , Qiu Shuang-Jian , Yang Xin-Rong , Shi Guo-Ming , Wu Bing , Dai Zhi , Liu Yin-Kun , Tang Zhao-You , Zhou Jian
Published: November 2008

Background.

Osteopontin (OPN) plays important roles in tumor progression and metastasis through binding to CD44 and integrin. The goal of this study was to elucidate the prognostic significance of OPN and CD44 in hepatocellular carcinoma patients.

Methods.

Tumor tissue microarray was used to detect the expression levels of OPN and CD44 in 302 hepatocellular carcinoma patients undergoing curative resection between 1997 and 2000 at our institute. Clinicopathologic data for these patients were investigated. The prognostic effects of OPN and CD44 were evaluated using the Kaplan–Meier method and compared using the log-rank test. The Spearman rank test and Fisher's exact test were applied to demonstrate correlations.

Results.

Both OPN and CD44 were independent predictors for overall survival and disease-free survival. When OPN and CD44 were taken into consideration together, the predictive range was extended and the sensitivity was improved, especially for those patients with normal serum α-fetoprotein levels. The 8-year overall survival and disease-free survival rates in OPN+ and/or CD44+ patients were 28.2% and 25.6%, respectively, which were significantly lower than those of OPN−CD44− patients (52.1% and 51.6%, respectively).

Conclusions.

OPN combined with CD44 is a promising independent predictor of tumor recurrence and survival in hepatocellular carcinoma patients.
Cold War Milton
Authors: Achinstein Sharon
Published: November 2008

Careful analysis of the historical context in which the first (1953) volume of Yale's magisterial edition of Milton's prose works, ‘Yale I,’ was produced reveals how the Milton it represents was shaped by current events – specifically, how Cold War developments threatened editor Don Wolfe's very American vision of what a liberal society should be. The exhaustive historical detail provided in Yale I's textual apparatus, its introduction and notes, not only portrays the political turmoil of seventeenth-century England but also represents Milton as a fierce opponent of political dangers clearly perceived as similar to those rampant in Cold War America – dangers such as McCarthyite anti-Communism, the rise of the defence-driven research university, and the ascendancy of that institution's favourite form of literary studies, the New Criticism. Ironically, Wolfe's presentism safeguarded historicist interest in Milton, inoculating Milton studies not only against the de-historicizing drive of New Criticism but also against the later innovations of the New Historicism.
A Physiological Function for Apolipoprotein(a): A Natural Regulator of the Inflammatory Response
Authors: Hoover-Plow Jane , Hart Erika , Gong Yanqing , Shchurin Aleksey , Schneeman Tracey
Published: November 2008

Structural similarities between apolipoprotein(a) (apo(a)), the unique apoprotein of lipoprotein(a), and plasminogen, the zymogen of plasmin, can interfere with functions of plasmin (ogen) in vitro. The purpose of this study was to evaluate the role of apo(a) in inflammation in vivo using apo(a) transgenic mice and to determine if effects are plasminogen-dependent using backgrounds that are either plasminogen-replete or plasminogen-deficient. After administration of peritoneal inflammatory stimuli, thioglycollate, bioimplants or lipopolysaccharide, the number of responding peritoneal neutrophils and macrophages were quantified. Apo(a), in either wild-type or plasminogen deficient backgrounds, inhibited neutrophil recruitment but had no effect on plasminogen-dependent macrophage recruitment. Macrophage-inflammatory protein-2, a neutrophil chemokine, was reduced in apo(a) mice, and injection of this chemokine prior to thioglycollate restored neutrophil recruitment in apo(a) transgenic mice. In the lipopolysaccharide model, mice with apo(a), unlike mice without apo(a), did not increase neutrophil recruitment in response to the stimulus. In the bioimplant model, neutrophil recruitment and neutrophil cytokines were reduced in apo(a)tg mice but only in a plasminogen-deficient background. These results indicate for the first time that apo(a), independent of plasminogen interaction, inhibits neutrophil recruitment in vivo in diverse peritoneal inflammatory models. Hence, apo(a) may function as a cell specific suppressor of the inflammatory response.
βig-h3 Interacts with α3β1 Integrin to Promote Adhesion and Migration of Human Hepatoma Cells
Authors: Tang Juan , Wu Ya-Mei , Zhao Pu , Jiang Jian-Li , Chen Zhi-Nan
Published: November 2008

βig-h3 is a TGF-induced extracellular matrix (ECM) protein. Our previous evidence suggests that β ig-h3 may promote adhesion and invasion potential of human hepatoma cells, but the mechanism underlying this process is still unknown. The present study identifies a pivotal role for molecules of the β ig-h3 signal transduction pathway. We demonstrated that β ig-h3 co-immunoprecipitated with α 3β 1 integrin in human 7721 hepatoma cells. The addition of α 3β 1 integrin antibodies inhibited the elevated adhesion and migration in β ig-h3-over-expressing 7721 cells, but not in β ig-h3 siRNA transfected 7721 cells. The expression and activity of integrin downstream molecules FAK and paxillin show a positive correlation with β ig-h3 expression in different human hepatoma cells. Levels of focal adhesions and stress fibers were decreased in β ig-h3 siRNA transfected 7721 cells. We suggest that by interaction with α 3β 1 integrin, β ig-h3 activates FAK-paxillin signaling linkage, leads to cytoskeleton reorganization, and thus enhances the metastatic potentials of human hepatoma cells.
Immunological, Hematological, and Glycemia Effects of Dietary Supplementation withAgaricus sylvaticuson Patients’ Colorectal Cancer
Authors: Fortes Renata C. , Novaes Maria Rita C. G. , Recôva Viviane L. , Melo Andresa L.
Published: November 2008

Objective: The aim of this study was to evaluate the effects of dietary supplementation with Agaricus sylvaticus fungus on hematological, immunological, and glycemia levels of postsurgical patients with colorectal cancer. Methods: A randomized, placebo-controlled, clinical trial was conducted at the General Hospital of Brazil for 6 months. Fifty-six patients with colorectal cancer (stages I, II, and III) were divided into 2 groups: A. sylvaticus (30 mg/kg/day) and placebo. Complete hemogram, serum iron, and fasting glycemia evaluations were carried out throughout the treatment course. Subjects were divided according to body mass index (BMI), sex, and stage of colorectal cancer. Data were analyzed using SPSS 14.0 programs, Student’s t test, and F statistical test, with P ≤ 0.05 considered significant. Results: After 6 months of supplementation, the group that received A. sylvaticus showed significant increases in hemoglobin ( P = 0.0001), hematocrit ( P = 0.0001), erythrocytes ( P = 0.01), mean cell volume ( P = 0.01), mean cell hemoglobin ( P = 0.0001), mean cell hemoglobin concentration ( P = 0.0001), and neutrophil levels ( P = 0.0001). The platelet count was significantly reduced ( P = 0.03), but remained within normal levels. No significant alterations were observed in the placebo group. The study group was composed of 32 women (57.1%) and 24 men (42.9%). Mean BMI was 24.65 kg/m2. Glycemia levels in the placebo group (average age 59.14 ± 12.95 years) were: initial, 94.36 ± 15.34 mg/dl; 3 months, 98.12 ± 15.54 mg/dl ( P = 0.03); and 6 months, 98.52 ± 9.03 mg/dl ( P = 0.01). Glycemia levels in the supplemented group (average age 56.34 ± 15.53 years) were: initial, 95.92 ± 11.64 mg/dl, 3 months, 94.88 ± 12.24 mg/dl ( P = 0.65); and 6 months, 92.86 ± 6.82 mg/dl ( P = 0.01). Conclusions: The results of this study suggest that supplementation with A. sylvaticus produces benefits in hematological and immunological parameters and can reduce glycemia levels in patients with colorectal cancer.