bluuebunny/crossref_metadata_2025 huggingface dataset:
Volatile anesthetics affect the morphology of rat glioma C6 cells via RhoA, ERK, and Akt activation
Authors: Tas Piet W.L. , Gambaryan Stepan , Roewer Norbert
Published: May 2007

Treatment of rat glioma C6 cells with the β‐receptor agonist isoproterenol induces a massive increase in cAMP. Concomitantly the cells change their morphology from a fibroblast‐type to an astrocyte‐like (stellated) cell shape. The stellated morphology can be completely reverted by thrombin and sphingosine‐1‐phosphate (S‐1‐P) but also to a certain extent by clinical concentrations of volatile anesthetics. The anesthetic‐induced reversion of the stellated cell shape seems to be mediated by a number of cellular alterations. Central to the effect is most likely a RhoA/Rho‐kinase activation, but also the MAPKK/MEK and the Akt/protein kinase B pathway are activated by the anesthetics. With the use of specific inhibitors we were able to show that activation of the MAPKK/MEK pathway inhibits, whereas activation of the Akt/protein kinase B pathway stimulates the reversal of the stellated cell shape by the anesthetics. In summary, volatile anesthetics affect the morphology of rat glioma C6 cells by activation of the RhoA/Rho kinase, the MAPKK/MEK, and the Akt/protein kinase B signaling pathways. J. Cell. Biochem. 102: 368–376, 2007. © 2007 Wiley‐Liss, Inc.
Trans‐ileocecal portal vein embolization as a preoperative treatment for right trisegmentectomy with caudate lobectomy
Authors: Shimura Tatsuo , Suehiro Taketoshi , Suzuki Hideki , Okada Kohji , Araki Kenichiro , Kuwano Hiroyuki
Published: May 2007

Background and Objectives

The indication of preoperative portal vein embolization (PVE) has been expanded to hepatocellular carcinoma, cholangiocellular carcinoma (CCC), hepatic metastasis, and gallbladder (GB) cancer as well as hilar cholangiocarcinoma (hCC). However, biliary cancers sometimes cause peritoneal dissemination.

Patients and Methods

We performed our preoperative trans‐ileocecal‐vein PVE (TIPE) method on 14 (3 GB cancer, 1 CCC, and 10 hCC), whose estimated residual liver volume was <30%.

Results

Out of 14 patients, peritoneal dissemination was encountered in two patients with GB cancer and one with hCC (21.4%) during our procedure. The estimated residual liver volume was 37.4 ± 2.7% at 14 days after PVE in patients without predisposing cholangitis, while those in patients with cholangitis was 29.3 ± 1.3% (P = 0.0002). No major complication due to the procedure was encountered in this series.

Conclusions

PTPE could be the first choice for patients with hCC, hepatocellular carcinoma, and hepatic metastases. Although the TIPE proposed here has some potential disadvantages, we would recommend it especially for patients with GB cancer because of its high potential to cause cancerous peritonitis. When a patient had predisposing cholangitis, radical operation should be scheduled on >21 days after PVE rather than on 14 days. J. Surg. Oncol. 2007;96:438–441. © 2007 Wiley‐Liss, Inc.
Orthogonal array design for the optimization of supercritical fluid extraction of baicalin from roots of Scutellaria baicalensis Georgi
Authors: Chang Yiling , Liu Ben , Shen Bo
Published: May 2007

Supercritical fluid was used to extract baicalin from the roots of Scutellaria baicalensis Georgi. An orthogonal array design (OAD), OA9(34), was employed as a chemometric method for the optimization of the supercritical fluid extraction of baicalin from the herbal medicine. Four parameters, namely, modifiers, temperature and pressure of supercritical fluid, and the dynamic extraction time, were studied and optimized by a three‐level OAD in which the interactions between the parameters were neglected. Determinations of the extracts were performed by high‐performance liquid chromatography. The effects of parameters were studied using analysis of variance. The results showed that selection of the modifier was the main factor in attaining higher yields of baicalin. While the other three factors had some effect on the extraction of the compound, the effect was much less than that of the modifiers. 1,2‐Propanediol‐modified supercritical fluid was more effective than 95% ethanol‐modified supercritical carbon dioxide or methanol‐modified supercritical carbon dioxide for the extraction of baicalin from the solid matrix. Finally, experimental conditions were proposed which can provide the highest extraction yield with respect to the considered factors.
Zinc corrosion runoff process induced by humid tropical climate
Authors: Veleva L. , Meraz E. , Acosta M.
Published: May 2007

Zinc and hot dip galvanized steel are frecuently used metals in building application. They have relatively good atmospheric resistance to corrosion, due to its oxidation in air and formation of protective rust on its surface, which acts as barrier between the metal and environment. However, some part of the rust can be dissolved by pluvial precipitations and water condensed on the metal surface. This process, called metal runoff, contributes for zinc dispersion in soils and waters. In order to make accurate estimation of zinc runoff induced by atmosphere in humid tropical climate, samples of pure Zn and hot dip galvanized steel have been exposed in the Gulf of Mexico. The data reveal that this process is strongly influenced by factors which determine the aggressivity of the environment (pluvial precipitations, cycles of dry and rainy periods, atmospheric pollutants, air humidity). High annual rates of zinc runoff (6.5 – 8.5 ± 0.30 g Zn m−2yr−1) were released, being the runoff 63 – 87% of the zinc corrosion rust. The zinc mass loss has been related to several independent parameters, presenting linear equation, which indicates the air contaminant SO2as the major factor controlling the runoff of zinc. The reported results show higher runoff of zinc samples, compared to that of hot dip galvanized steel
Effect of aging time and temperature on exfoliation corrosion of aluminum alloys 2024‐T3 and 7075‐T6
Authors: Khoshnaw F. M. , Gardi R. H.
Published: May 2007

Two types of aluminum alloys, 2024‐T3 and 7075‐T6, have been selected in this study to investigate the effect of metallurgical aspects on exfoliation corrosion. To determine and evaluate the metallurgical effects of heat treatments on corrosion behaviour of these alloys, G34 ASTM test was selected to investigate the exfoliation corrosion behaviour. The results showed that with increasing the aging time for the aluminum alloy type 2024‐T3 the susceptibility to exfoliation corrosion increases, while for type 7075‐T6 decreased. These results refer to precipitation of the intermetallic compound phases such as CuAl2, and MgZn2, in 2024‐T3 and 7075‐T6 respectively. The amount of these phases increases with increasing the aging time for both alloys. The investigations showed the phases that initiate in 2024‐T3 act as anode sites while in 7075‐T6 they act as cathode sites.
An in situ FT‐IR evaluation of candidate organic corrosion inhibitors for carbon steel in contact with alkaline aqueous solutions
Authors: Bozzini B. , Mele C. , Romanello V.
Published: May 2007

The influence of some organic additives on the anodic behaviour of a carbon steel electrode in contact with alkaline aqueous solutions was studied by in situ Fourier transform infrared (FT‐IR) spectroscopy. FT‐IR spectroscopy allows to obtain information at the molecular level regarding the metal‐electrolyte interface. The following molecules have been considered: (i) benzyldimethylphenylammonium chloride (BDMPAC), (ii) glutamic acid, (iii) triethylenetetramine (TETA), (iv) sodium tartrate and (v) sodium benzoate. Potential‐dependent spectra have been recorded for the different investigated systems. Quantitative information about the formation kinetics of corrosion products was derived by numerical analysis of the peak area as a function of the applied potential for the different systems investigated.
Crevice corrosion monitoring of titanium and its alloys using microelectrodes
Authors: Rajendran N. , Nishimura T.
Published: May 2007

Crevice corrosion of titanium and its alloys in 10% sodium chloride was investigated at 100°C with the aid of microelectrodes. Potential, pH and chloride ion concentration inside the crevice were monitored using an Ag/AgCl electrode, a tungsten microelectrode and a Ag/AgCl chloride ion selective microelectrode, respectively. The pH and Cl− concentrations within the crevice were calculated from the standard potential‐pH and potential‐log[Cl−] calibration curves. The effect of Mo on the crevice corrosion of titanium was also studied. The passivation behavior on the titanium and Ti‐15%Mo alloy was studied using electrochemical impedance studies. There was no apparent change in pH and Cl− ion activity inside the crevice for the alloy at 100°C, whereas a marginal decrease in pH and increase in Cl− ion concentration were observed for pure titanium. Thus pure titanium is susceptible to crevice corrosion in hot 10% NaCl solutions at 100°C. The chloride ion activity was found to be reduced for the alloy so that the pH inside the crevice increased. The corrosion reaction resistance (Rt) was found to increase with the addition of Mo as an alloying element. It also increases with externally applied anodic potential. Hence, Mo is an effective alloying element, which enhances the crevice corrosion resistance of titanium.
Preparation and Characterization of Hybrid Nanocomposite Coatings by Cationic UV‐Curing and the Sol‐Gel Process of a Vinyl Ether Based System
Authors: Sangermano Marco , Amerio Ezio , Epicoco Paolo , Priola Aldo , Rizza Giancarlo , Malucelli Giulio
Published: May 2007

Organic/inorganic hybrid nanocomposite coatings were prepared through a dual‐cure process involving the cationic photopolymerization of a vinyl ether based system and the condensation of an alkoxysilane inorganic precursor. All formulations produced transparent cured films characterized by high gel contents. An increase in glass transition temperature and an increase in storage modulus above Tg in the rubbery plateau were observed with increasing TEOS content in the photocurable formulation. TEM micrographs showed that the organic and inorganic phases were strictly interconnected with no macroscopic phase separation; the sizes of the silica domains in the polymeric matrix were 3–5 nm.

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A network isolation algorithm
Authors: Bellmore M. , Bennington G. , Luhore S.
Published: May 2007

A set of edges D called an isolation set, is said to isolate a set of nodes R from an undirected network if every chain between the nodes in R contains at least one edge from the set D. Associated with each edge of the network is a positive cost. The isolation problem is concerned with finding an isolation set such that the sum of its edge costs is a minimum.

This paper formulates the problem of determining the minimal cost isolation as a 0–1 integer linear programming problem. An algorithm is presented which applies a branch and bound enumerative scheme to a decomposed linear program whose dual subproblems are minimal cost network flow problems. Computational results are given.

The problem is also formulated as a special quadratic assignment problem and an algorithm is presented that finds a local optimal solution. This local solution is used for an initial bound.
Resource allocation for transportation
Authors: Bennington G. , Lubore S.
Published: May 2007

A linear programming formulation is described that will permit the optimal assignment of transportation resources (vehicles) and movement requirements to a network consisting of a set of designated origins, ports of embarkation, enroute bases, ports of debarkation, and destinations to achieve a prescribed schedule of arrivals.
A queueing process with varying degree of service
Authors: Scott Meckinley
Published: May 2007

This article describes and presents some results of the analysis of a queueing process where the degree of service given to a customer is subject to control by the management. The control doctrine used is based on the queue length and also on the recent history of the system.
A methodology for estimating expected usage of repair parts with application to parts with no usage history
Authors: Haber Sheldon E. , Sitgreaves Rosedith
Published: May 2007

In this paper a model is presented which focuses on the difficult problem of predicting demands for items with extremely low usage rates. These form the bulk of repair parts in military systems. The basic notion underlying the model is the pooling of usage data for common design items with movement for the purpose of estimating usage rates for similar items which have shown no movement.

A unique feature of the model is that it also makes possible the estimation of usage rates for items newly introduced into a system for which no previous usage history is available.
A note on the calculation of expected time‐weighted backorders over a given interval
Authors: Ho Chung‐Mei
Published: May 2007

Two formulae are presented for calculating expected time‐weighted backorders over a fixed time interval. One formula is a more precise form of a result found in the literature and is found using a direct intuitive approach. The second formula is derived using the steady. State distribution of inventory and is directly compatible with the use of steady‐state (R, Q) models.

The two formulae are compared and reconciled.
Optimal control of multi‐channel service systems
Authors: Magazine M. J.
Published: May 2007

D. P. Heyman, M. Sobel, and M. J. Magazine among others have shown existence of an optimal policy for control of single server queuing systems. For queues under periodic review existence of an analogous rule is established for multi‐server systems. Formulation as a dynamic programming problem is given and proofs for existence are presented for finite horizon, infinite horizon and average cost criteria.
The transportation paradox
Authors: Szwarc Wlodzimierz
Published: May 2007

A paradox arises when a transportation problem admits to a total cost solution which is lower than the optimum and is attainable by shipping larger quantities of goods over the same routes that were previously designated as optimal. That is, falling total costs are present in moving to the greater shipment quantities. Necessary conditions for this to occur are established and an algorithm for solving this expanded transportation problem is supplied.
The interface of computer science and statistics
Authors: Goodman A. F.
Published: May 2007

Current scientific, technical, and management progress is characterized by the generation of a tremendous amount of data for analysis. This, in turn, poses a significant challenge: to effectively and efficiently extract meaningful information from the large volume of data. Two relatively young professions, computer science and statistics, are intimately linked in any response to the challenge. They have consequently become indispensable to scientific, technical, and management progress, occupying a position at its very heart

Computer science and statistics have each been separately documented by many books as well as numerous papers. However, the interface of computer science and statistics, the area of their interaction, has been documented only in part. This paper begins characterization of the entire interface by providing a structure and an historical background for it

A structure for the interface is introduced initially, followed by an historical background for the interface presented in two parts. First to be summarized is the evolution of the interface from an interweaving of the mechanical prerequisites to the computer and mathematical prerequisities to computer science and of the foundations for probability and statistics. Development of statistics prior to 1900 then is reviewed.
Statistical concepts in computational mathematics
Authors: Juncosa M. L.
Published: May 2007

For a young science and even for most old ones, the intensity and variety of activities involved in computer science are unsurpassed. In an effort to provide the extremely varied training needed in the field, curriculum planners have tended to slight probability and statistics. Rarely has it been a requisite and only occasionally a desired elective

However, not only is an adequate foundation in probability and statistics necessary for such external computer applications as tracking and other data reduction, Monte Carlo techniques, gaming, operations research, traffic analyses, etc., but it also plays an important role in internal applications to computer science and technology

This effort in Rand's continuing study of computational mathematics and its applications offers a number of examples in various areas of computational mathematics and computing machine arithmetic‐to say nothing of computer design, time sharing, and the like‐to support the thesis that probability and statistics should be a requisite, not simply an elective or, even worse, ignored, at any institution offering a program in computer science. Further more, a potentially profitable source of research problems can be found in the interface between probability and statistics and computer science.
Hit probability for a chain‐like series of shots—a simple formula
Authors: Zahle T. U.
Published: May 2007

To find the hit probability for a series of correlated shots is, with conventional methods, a very tedious job even for the simplest statistical distributions. Experimental data, however, commonly show the shots lying chain‐like on smooth curves about the target. For this case this paper introduces a new method of finding the hit probability without the use of correlation coefficients. The method is based on a transformation, where the target is transformed into a point and each bullet into an area the size of the target.
The bottleneck transportation problem
Authors: Garfinkel R. S. , Rao M. R.
Published: May 2007

The bottleneck transportation problem can be stated as follows: A set of supplies and a set of demands are specified such that the total supply is equal to the total demand. There is a transportation time associated between each supply point and each demand point. It is required to find a feasible distribution (of the supplies) which minimizes the maximum transportaton time associated between a supply point and a demand point such that the distribution between the two points is positive. In addition, one may wish to find from among all optimal solutions to the bottleneck transportation problem, a solution which minimizes the total distribution that requires the maximum time

Two algorithms are given for solving the above problems. One of them is a primal approach in the sense that improving fcasible solutions are obtained at each iteration. The other is a “threshold” algorithm which is found to be far superior computationally.
Integer points on the Gomory fractional cut (hyperplane)
Authors: Salkin Harvey M. , Breining Patrice
Published: May 2007

In this paper we show that the Gomory fractional cut (hyperplane) for the integer program is either void of integer points or contains an infinite number of them. The conditions for each case are presented. Also, we derive a stronger cut from the hyperplane which does not intersect integer points.
Scheduling with earliest start and due date constraints
Authors: Bratley Paul , Florian Michael , Robillard Pierre
Published: May 2007

We consider the scheduling of n tasks on a single resource. Each task becomes available for processing at time ai, must be completed by time bi, and requires di time units for processing. The aim is to find a schedule that minimizes the elapsed time to complete all jobs. We present solution algorithms for this problem when job splitting is permitted and when job splitting is not permitted. Then we consider several scheduling situations which arise in practice where these models may apply.
A bivariate normal theory maximum‐likelihood technique when certain variances are known
Authors: Locks Mitchell O.
Published: May 2007

A maximum‐likelihood technique is described for estimating the bivariate normal distribution of the estimates of two or more related values when data are obtained from several different sources, each having known variance. The problem is comparable, in the bivariate sense to estimating the mean of a normal population with known variance. The results tend to be dominated by those sources of data associated with the smallest variances.
On models for business failure data
Authors: Dubey Satya D.
Published: May 2007

It is pointed out in this paper that Lomax's hyperbolic function is a special case of both Compound Gamma and Compound Weibull distributions, and both of these distributions provide better models for Lomax's business failure data than his hyperbolic and exponential functions. Since his exponential function fails to yield a valid distribution function, a necessary condition is established to remedy this drawback. In the light of this result, his exponential function is modified in several ways. It is further shown that a natural complement of Lomax's exponential function does not suffer from this drawback.
The multicommodity network flow model revised to include vehicle per time period and node constraints
Authors: Weigel Henry S. , Cremeans John E.
Published: May 2007

The minimum‐cost formulation of the problem of determining multicommodity flows over a capacitated network subject to resource constraints has been treated in previobs papers. In those treatments only capacitated arcs were assumed and a uniform unit of measure like short tons was used for all commodities. This paper treats the effect of constraints on the nodes of the network, allows the commodities to be measured in their “natural” units and allows the network capacities to be expressed in vehicles per time period‐in some cases giving a more accurate representation of the capacities of the network. This paper describes the solution procedure which uses the column generation technique; it also discusses computational experience.
The payment scheduling problem
Authors: Grinold Richard C.
Published: May 2007

Large complicated projects with interdependent activities can be described by project networks. Arcs represent activities, nodes represent events, and the network's structure defines the relation between activities and events. A schedule associates an occurrence time with each event: the project can be scheduled in several different ways. We assume that a known amount of cash changes hands at each event. Given any schedule the present value of all cash transactions can be calculated. The payment scheduling problem looks for a schedule that maximizes the present value of all transactions.

This problem was first introduced by Russell [2]; it is a nonlinear program with linear constraints and a nonconcave objective. This paper demonstrates that the payment scheduling problem can be transformed into an equivalent linear program. The linear program has the structure of a weighted distribution problem and an efficient procedure is presented for its solution. The algorithm requires the solution of triangular systems of equations with all matrix coefficients equal to ± or 0.
Sequential bid selection by stochastic approximation
Authors: Agnew Robert A.
Published: May 2007

Suppose that a contractor is faced with a sequence of “minimum bid wins contract” competitions. Assuming that a contractor knows his cost to fulfill the contract at each competition and that competitors are merely informed whether or not they have won, bids may be selected sequentially via a tailored stochastic approximation procedure. The efficacy of this approach in certain bidding environments is investigated.
Stochastic duels involving reliability
Authors: Thompson David E.
Published: May 2007

The reliability of weapons in combat has been treated by Bhashyam in the context of a stochastic duel characterized by fixed ammunition supplies. negative exponentially distributed firing times and weapon lifetimes, and a fixed number of spare weapons for each duelist. The present paper takes a different approach by starting with the fundamental duel of Ancker and Williams, characterized by unlimited ammunition and by ordinary renewal firing times, and adding to it weapon lifetimes which can be functions of time or of round position in the firing sequence. Probabilities of winning and tieing are derived and it is shown that under certain conditions the weapon lifetimes are equivalent to random time and ammunition limits.
An operator theory of parametric programming for the transportation problem‐I
Authors: Srinivasan V. , Thompson G. L.
Published: May 2007

This paper investigates the effect on the optimum solution of a (capacitated) transportation problem when the data of the problem (the rim conditions‐i. e., the warehouse supplies and market demands‐the per unit transportation costs and the upper bounds) are continuously varied as a (linear) function of a single parameter. An operator theory is developed and algorithms provided for applying rim and cost operators that effect the transformation of optimum solution associated with changes in rim conditions and unit costs. Bound operators that effect changes in upper bounds are shown to be equivalent to rim operators. The discussion in this paper is limited to basis preserving operators for which the changes in the data are such that the optimum basis structures are preserved.
An operator theory of parametric programming for the transportation problem‐II
Authors: Srinivasan V. , Thompson G. L.
Published: May 2007

This paper investigates the effect on the optimum solution of a (capacitated) transportation problem when the data of the problem (the rim conditions‐i. e., the warehouse supplies and market demands‐, the per unit transportation costs and the upper bounds) are continuously varied as a (linear) function of a single parameter. Operators that effect the transformation of optimum solution associated with such data changes, are shown to be a product of basis preserving operators (described in the earlier paper) that operate on a sequence of adjacent basis structures. Algorithms are provided for both rim and cost operators. The paper concludes with a discussion of the economic and managerial interpretations of the operators.
Properties of a multifacility location problem involving euclidian distances
Authors: Francis Richard L. , Cabot A. Victor
Published: May 2007

This paper considers a problem of locating new facilities in the plane with respect to existing facilities, the locations of which are known. The problem consists of finding locations of new facilities which will minimize a total cost function which consists of a sum of costs directly proportional to the Euclidian distances among the new facilities, and costs directly proportional to the Euclidian distances between new and existing facilities. It is established that the total cost function has a minimum; necessary conditions for a mimumum are obtained; necessary and sufficient conditions are obtained for the function to be strictly convex (it is always convex); when the problem is “well structured,” it is established that for a minimum cost solution the locations of the new facilities will lie in the convex hull of the locations of the existing facilities. Also, a dual to the problem is obtained and interpreted; necessary and sufficient conditions for optimum solutions to the problem, and to its dual, are developed, as well as complementary slackness conditions. Many of the properties to be presented are motivated by, based on, and extend the results of Kuhn's study of the location problem known as the General Fermat Problem.
On the discrete‐time queue length distribution under markov‐dependent phases
Authors: Chaudhry M. L.
Published: May 2007

The technique of probability generating functions has been applied to solve the steady state behavior of a discrete‐time, single‐channel, queueing problem wherein the arrivals to the queue at consecutive time‐marks are statistically independent, but the service is accomplished in phases which are Markov‐dependent. Special cases of importance have been discussed. In the end, mean number of phases, its special cases, the mean queue lengths, and the variances have been ascertained.
Heuristic solution to a discrete collection model
Authors: Saipe Alan L. , Cunningham A. A.
Published: May 2007

A discrete time Collection Model is formulated, involving the completion of a touring objective on a network with stochastic node states. Heuristic touring strategies are constructed, there being as yet inadequate analytic results for its optimal solution. Effectiveness of the heuristics is assessed by comparing expected tour times under the heuristics with expected tour times given perfect information. A branch and bound algorithm is presented for computing the perfect information tour times.
A note comparing glover's and young's simplified primal algorithms
Authors: Salkin Harvey M.
Published: May 2007

Glover and Young, References [4] and [8], respectively, present convergent primal integer programming algorithms. The algorithm outlined in Young's paper (which was deliberately specialized) is shown to be a special case of the Glover algorithm under his acceptable source row selection, Rule 1.
An economic model for planning strategic mobility posture
Authors: Bennington G. , Gsellman L. , Lubore S.
Published: May 2007

This paper describes a linear programming model used to perform cost‐effectiveness analysis to determine the requirements for military strategic mobility resources. Expenditures for three classes of economic alternatives are considered: purchase of transportation resources; prepositioning of material; and augmentation of port facilities. The mix of economic alternatives that maximizes the effectiveness of the resultant transportation system is determined for a given investment level. By repeating the analysis for several levels of investment, a cost‐effectiveness tradeoff curve can be developed.
A mixed optimization technique for the generalized machine replacement problem
Authors: Sethi S. P. , Morton T. E.
Published: May 2007

A mixed optimization technique for optimal machine replacement is presented which allows much more flexibility than previous models. Optimal purchase, maintenance and sale of a given machine between any two given points in time is treated as a subproblem, which one may choose to solve via control theory, dynamic programming, or practical engineering considerations. (A control theory formulation is used in the paper as an illustration.) These subproblem solutions are then incorporated into a Wagner‐Whitin formulation for solution of the full problem. The technique is particularly useful for problems with such asymmetries as an existing initial machine or uneven technological change. A simple numerical example is solved in the Appendix.
A defense allocation problem with development costs
Authors: Shere Kenneth D. , Cohen Edgar A.
Published: May 2007

In this paper, the mathematical model for the allocation of resources among a general mix of percentage vulnerable and of numerically vulnerable weapon systems is presented and solved. Percentage vulnerable systems consist of mobile weapons which are difficult to locate, but relatively easy to destroy once located; numerically vulnerable systems comprise easily located fixed base weapons which are difficult to destroy. The distinguishing feature of this analysis is the inclusion of development costs. The theory of max‐min is extended as necessary to solve this problem. References are provided to a sequence of earlier versions of this problem.
On the isbell and marlow fire programming problem
Authors: Taylor James G.
Published: May 2007

A complete solution is derived to the Isbell and Marlow fire programming problem. The original work of Isbell and Marlow has been extended by determining the regions of the initial state space from which optimal paths lead to each of the terminal states of combat. The solution process has involved determining the domain of controllability for each of the terminal states of combat and the determination of dispersal surfaces. This solution process suggests a solution procedure applicable to a wider class of tactical allocation problems, terminal control attrition differential games. The structure of optimal target engagement policies in “fights to the finish” is discussed.
Stationary (s, s) policies for a finite horizon
Authors: Wheeler Alan C.
Published: May 2007

In the finite‐horizon stochastic (s, S) inventory model with periodic review the parameters of the optimal policy generally vary with the length of the horizon. A stationary policy, however, is easier to implement and may be easier to calculate. This paper studies optimal stationary policies for a finite horizon and relates them to optimal policies through their relation to optimal stationary policies for an infinite horizon.
On a sequential test procedure with delayed observations
Authors: Chang R. C. , Ehrenfeld S.
Published: May 2007

This paper considers sequential test procedures to decision problems where there exists time delays in obtaining observations.
Equivalent knapsack‐type formulations of bounded integer linear programs: An alternative approach
Authors: Padberg Manfred W.
Published: May 2007

In this paper we show that every bounded integer linear program can be transformed into an integer program involving one single linear constraint and upper and lower bounds on the variables, such that the solution space of the original problem coincides with that one of the equivalent knapsack‐type problem.
Constructing bimatrix games with special properties
Authors: Millham C. B.
Published: May 2007

This work is concerned primarily with presenting techniques for constructing bimatrix games with predetermined equilibrium points. Some partial results on Nash‐solvability are also given.
Scheduling data transmission under an {si; o} policy
Authors: Sahney Vinod K.
Published: May 2007

This paper discusses scheduling of data transmission when data can only be transmitted in one direction at a time. A common policy used is the so‐called alternating priority policy. In this paper we select a more general class of policies named the {Si; O} policy. We show how to determine the optimal parameters of the {Si; O} policy for given system parameters. We also give a simple example to show that {Si; O} policy is, in fact, better then alternating priority policy.
Productivity estimates of the strategic airlift system by the use of simulation
Authors: Nolan Richard L. , Mastroberti Rocci
Published: May 2007

Although the strategic airlift system is under continuous analysis, C‐5A problems provided impetus to analyze the airlift system productivity function by using a large‐scale simulation model. Development of the simulation model (Simulation of Airlift Resources ‐ SOAR) was initiated by the Office of Secretary of Defense (Systems Analysis) in 1966. SOAR had barely become operational in time for the study in November 1968.

Since limited verification and validation tests had been performed on the simulation model, the design of experiments was of critical importance. The experimental design had to be flexible enough to salvage the maximum amount of information possible upon the discovery of either a verification or validation error. In addition, the experimental design was required to accommodate the estimation of a large number of possibly changing independent variables.

The experimental design developed for the analysis was full factorial design sets for a finite number of factors. Initial analysis began with aggregated sets of factors at two levels, and information gained from experiment execution was used to parse the sets. The process was sequential and parsing continued until the major explanatory independent variables were identified or enough information was obtained to eliminate the factor from further direct analysis. This design permitted the overlapping of simulation runs to fill out the factorial design sets.

In addition to estimating the airlift productivity function, several other findings are reported which tended to disprove previous assumptions about the nature of the strategic airlift system.
Optimal location of public facilities
Authors: Dee Norbert , Liebman Jon C.
Published: May 2007

Location of both public and private facilities has become an important consideration in today's society. Progress in solution of location problems has been impeded by difficulty of the fixed charge problem and the lack of an efficient algorithm for large problems.

In this paper a method is developed for solving large‐scale public location problems. An implicit enumeration scheme with an imbedded transportation algorithm forms the basis of the solution technique.
Structured markovian decision problems
Authors: Kalymon Basil A.
Published: May 2007

Structured finite action‐finite state space discounted Markovian decision problems are analyzed. Any problem of a general class is shown to be equivalent to a “separated” problem with decomposable problem structure. A modified policy iteration approach is developed for this decomposable reformulation. Both analytic and computer evaluations of the decomposition algorithm's effectiveness are presented.
Polaroids: A new tool in non‐convex and in integer programming
Authors: Burdet Claude‐Alain
Published: May 2007

This paper presents a generalization, called polaroid, of the concept of polar sets

A list of properties satisfied by polaroids is established indicating that the new concept nay be fruitfully used in an area of non‐convex (called here polar) programming as well as in integer programming, by means of polaroid cuts; this class of new cuts contains the ones defined by Tuy for concave programming (a special case of polar programming) and by Balas integer programming; it furthermore provides for new degrees of freedom in the construction of algorithms in the above‐mentioned areas of mathematical programming.
A squared‐variable transformation approach to nonlinear programming optimality conditions
Authors: Taylor James G.
Published: May 2007

We show that the well‐known necessary and sufficient conditions for a relative maximum of a nonlinear differentiable objective function with nonnegative variables constrained by nonlinear differentiable inequalities may be derived using the classical theory of equality constrained optimization problems with unrestricted variables. To do this we transform the original inequality‐constrained problem to an equivalent equality‐constrained problem by means of a well‐known squared‐variable transformation. Our major result is to show that second order conditions must be used to obtain the Kuhn‐Tucker conditions by this approach. Our nonlinear programming results are motivated by the development of some well‐known linear programming results by this approach.
Parametric analysis of linear programs with upper bounded variables
Authors: Panwalkar S. S.
Published: May 2007

Linear programming problems with upper bounded variables can be solved by regular simplex method by considering upper bounding constraints as explicit constraints of the problem. However, more efficient methods exist which consider these upper bound constraints implicitly. When parametric analysis for problems with upper bounds is to be carried out, one can use the regular parameter analysis by considering the upper bound constraints explicitly. This paper develops formulas for parametric analysis where upper bound constraints are used implicitly, thus reducing the size of the basic matrix.
Requirements of an “optimizer” for computer simulations
Authors: Smith Dennis E.
Published: May 2007

Computer simulation has many advantages. However, one major disadvantage is that, in all too many cases, the attempt to use computer simulation to find an optimum solution to a problem rapidly degenerates into a trial‐and‐error process. Techniques for overcoming this disadvantage, i. e., for making optimization and computer simulation more compatible, are applicable at two points in the development of the overall computer simulation. Techniques which are used within actual construction of the mathematical models comprising the simulation will be labeled as internal methods, while those which are used after the simulation has been completely developed will be termed external methods

Because external methods appear to offer the largest potential payoff, discussion is restricted to these methods, which are essentially search techniques. In addition, the development of an “Optimizer” computer program based on these techniques is suggested

Although drawbacks to the use of search techniques in the computer simulation framework exist, these techniques do offer potential for “optimization.” The modification of these techniques to satisfy the requirements of an “Optimizer” is discussed.
Three ways of obtaining the average cost expression in a problem related to joint replenishment inventory control
Authors: Silver Edward A.
Published: May 2007

This paper does not present a new result, rather it is meant to illustrate the choice of modelling procedures available to an analyst in a typical inventory control problem. The same “average cost per unit time” expression is developed by three quite different procedures. This variety of approaches, as well as the recounting of the author's chronological efforts to solve the problem, should be of interest to the reader. The specific inventory problem studied is one where the controller of an item is faced with random opportunities for replenishment at a reduced setup cost; the problem is an integral component of the broader problem of inventory control of a group of items whose replenishments are coordinated to reduce the costs of production, procurement, and/or transportation.
The lower bounded and partial upper bounded distribution model
Authors: Wagner Harvey M.
Published: May 2007

This paper pruvides a smaller equivalelnt bounded variable transportation problem than that in Charnes, Glover, and Klingman [1] for the lower bounded and partial upper bounded distribution model.
An approach to the allocation of common costs of multi‐mission systems
Authors: Crow Robert Thomas
Published: May 2007

Many Naval systems, as well as other military and civilian systems, generate multiple missions. An outstanding problem in cost analysis is how to allocate the costs of such missions so that their true costs can be determined and resource allocation optimized. This paper presents a simple approach to handling this problem for single systems. The approach is based on the theory of peak‐load pricing as developed by Marcel Boiteux. The basic principle is that the long‐run marginal cost of a mission must be equal to its “price.” The implication of this is that if missions can cover their own marginal costs, they should also be allocated some of the marginal common costs. The proportion of costs to be allocated is shown to a function of not only the mission‐specific marginal costs and the common marginal costs, but also of the “mission price.” Thus, it is shown that measures of effectiveness must be developed for rational cost allocation. The measurement of effectiveness has long been an intractable problem, however. Therefore, several possible means of getting around this problem are presented in the development of the concept of relative mission prices.
Min/max bounds for dynamic network flows
Authors: Wilkinson W. L.
Published: May 2007

This paper presents an algorithm for determining the upper and lower bounds for arc flows in a maximal dynamic flow solution. The procedure is basically an extended application of the Ford‐Fulkerson dynamic flow algorithm which also solves the minimal cost flow problem. A simple example is included. The presence of bounded optimal are flows entertains the notion that one can pick a particular solution which is preferable by secondary criteria.
Concave minimization over a convex polyhedron
Authors: Taha Hamdy A.
Published: May 2007

A general algorithm is developed for minimizing a well defined concave function over a convex polyhedron. The algorithm is basically a branch and bound technique which utilizes a special cutting plane procedure to' identify the global minimum extreme point of the convex polyhedron. The indicated cutting plane method is based on Glover's general theory for constructing legitimate cuts to identify certain points in a given convex polyhedron. It is shown that the crux of the algorithm is the development of a linear undrestimator for the constrained concave objective function. Applications of the algorithm to the fixed‐charge problem, the separable concave programming problem, the quadratic problem, and the 0‐1 mixed integer problem are discussed. Computer results for the fixed‐charge problem are also presented.
Some experiments in global optimization
Authors: Hartman James K.
Published: May 2007

When applied to a problem which has more than one local optimal solution, most nonlinear programming algorithms will terminate with the first local solution found. Several methods have been suggested for extending the search to find the global optimum of such a nonlinear program. In this report we present the results of some numerical experiments designed to compare the performance of various strategies for finding the global solution.
Generalized multicomponent systems under cannibalization
Authors: Hochberg Murray
Published: May 2007

Using the theory of Hirsch, Meisner, and Boll, we study the consequences of interchanging parts within a generalized coherent structure. This procedure has been termed “cannibalization.” The theory of cannibalization is extended to the case where each component can operate at several levels of partial performance and a representation theorem is derived, which expresses the state of a system as a function of the number of working parts at each level. The stochastic theory of these systems is then investigated.
A theory of ideal linear weights for heterogeneous combat forces
Authors: Howes David R. , Thrall Robert M.
Published: May 2007

Detailed combat simulations can produce effectiveness tables which measure the effectiveness of each weapon class on one side of an engagement, battle, or campaign to each weapon class on the other. Effectiveness tables may also be constructed in other ways

This paper assumes that effectiveness tables are given and shows how to construct from them a system of weapon weights each of which is a weighted average of the effects of a given weapon against each of the enemy's weapons. These weights utilize the Perron‐ Frobenius theory of eigenvectors of nonnegative matrices. Methods of calculation are discussed and some interpretations are given for both the irreducible and reducible cases.
Further light on nonparametric selection efficiency
Authors: Dudewicz Edward J. , Fan Chung‐Lien
Published: May 2007

A nonparametric selection procedure 𝒫bs was proposed by Bechhofer and Sobel (1958) and studied by Dudewicz (1971) in comparison with other procedures under normal and uniform alternatives. He found 𝒫BS always required larger sample sizes, sometimes substantially so. For 2‐point populations we find more extreme results. We also find that 𝒫BS may be substantially better than reasonable competitors designed specifically for 2‐point populations. Finally, a new nonparametric selection procedure (conjectured to be better than 𝒫BS) is proposed.
Simplified estimates of the parameters of the double exponential distribution based on optimum order statistics from a middle‐censored sample
Authors: Ahsanullah M. , Rahim M. A.
Published: May 2007

In an ordered sample from a given population, a few of the consecutive observations from somewhere in the middle may be missing Further, we may be constrained to use a few, and not all, of the remaining observations for purposes of estimation of population parameters. In this paper, such a situation is considered for the double exponential distribution and best linear unbiased estimates are obtained for its parameters, based on a choice of an optimum set of order statistics when the number of observations in the set are prefixed.