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Fixed Amount (fixed + amount)
Selected AbstractsDecentralized adaptive scheduling using consensus variablesINTERNATIONAL JOURNAL OF ROBUST AND NONLINEAR CONTROL, Issue 10-11 2007Kevin L. Moore Abstract In this paper we present a new approach to decentralized adaptive scheduling, using recent results on the control of consensus variables in graphs with nearest-neighbour communication topologies. First, existing results for single consensus variables are extended to include the cases of forced consensus, when one of the negotiating agents is driven by a setpoint, and of constrained consensus, where multiple consensus variables are required to be separated by a fixed amount. Next, we consider a class of adaptive scheduling problems, whereby a set of decentralized coordinators should cooperate to adapt shared schedule times in response to disturbances or changes in the system. Our approach is to choose task timings to be the consensus variables in the system. The utility of these ideas is illustrated using the example of a synchronized strike mission. Copyright © 2006 John Wiley & Sons, Ltd. [source] Social discounting and delay discountingJOURNAL OF BEHAVIORAL DECISION MAKING, Issue 1 2008Howard Rachlin Abstract Social discounting was measured as the amount of money a participant was willing to forgo to give a fixed amount (usually $75) to another person. In the first experiment, amount forgone was a hyperbolic function of the social distance between the giver and receiver. In the second experiment, degree of social discounting was an increasing function of reward magnitude whereas degree of delay discounting was a decreasing function of reward magnitude. In the third experiment, the shape of the function relating delayed rewards to equally valued immediate rewards for another person was predicted from individual delay and social discount functions. All in all, the studies show that the social discount function, like delay and probability discount functions, is hyperbolic in form. Copyright © 2007 John Wiley & Sons, Ltd. [source] Measuring Permeability of Rigid Materials by a Beam-Bending Method: I, TheoryJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 9 2000George W. Scherer When a saturated porous material is deformed, pressure gradients are created in the liquid, and the liquid flows within the pores to equilibrate the pressure. This phenomenon can be exploited to measure permeability: A rod of saturated porous material is instantaneously bent by a fixed amount, and the force required to sustain the deflection is measured as a function of time. The force decreases as the liquid flows through the pore network, and the rate of decrease depends on the permeability. This technique has been applied successfully to determine the permeability of gels, as well as their viscoelastic properties; in this paper the method is extended to ceramic materials, such as porous glass and cement paste. The theory has been modified to take account of the compressibility of the solid and liquid phases (whereas, those factors are negligible for gels). Analyses are presented for constant deflection, constant rate of deflection, and sinusoidal oscillation, where the solid phase is either purely elastic or viscoelastic, and the beam is either cylindrical or square. Experimental tests on Vycor® glass and cement paste will be presented in companion papers. [source] PRICING IN AN INCOMPLETE MARKET WITH AN AFFINE TERM STRUCTUREMATHEMATICAL FINANCE, Issue 3 2004Virginia R. Young We apply the principle of equivalent utility to calculate the indifference price of the writer of a contingent claim in an incomplete market. To recognize the long-term nature of many such claims, we allow the short rate to be random in such a way that the term structure is affine. We also consider a general diffusion process for the risky stock (index) in our market. In a complete market setting, the resulting indifference price is the same as the one obtained by no-arbitrage arguments. We also show how to compute indifference prices for two types of contingent claims in an incomplete market, in the case for which the utility function is exponential. The first is a catastrophe risk bond that pays a fixed amount at a given time if a catastrophe does not occur before that time. The second is equity-indexed term life insurance which pays a death benefit that is a function of the short rate and stock price at the random time of the death of the insured. Because we assume that the occurrence of the catastrophe or the death of the insured is independent of the financial market, the markets for the catastrophe risk bond and the equity-indexed life insurance are incomplete. [source] Optimal control of a revenue management system with dynamic pricing facing linear demandOPTIMAL CONTROL APPLICATIONS AND METHODS, Issue 6 2006Fee-Seng Chou Abstract This paper considers a dynamic pricing problem over a finite horizon where demand for a product is a time-varying linear function of price. It is assumed that at the start of the horizon there is a fixed amount of the product available. The decision problem is to determine the optimal price at each time period in order to maximize the total revenue generated from the sale of the product. In order to obtain structural results we formulate the decision problem as an optimal control problem and solve it using Pontryagin's principle. For those problems which are not easily solvable when formulated as an optimal control problem, we present a simple convergent algorithm based on Pontryagin's principle that involves solving a sequence of very small quadratic programming (QP) problems. We also consider the case where the initial inventory of the product is a decision variable. We then analyse the two-product version of the problem where the linear demand functions are defined in the sense of Bertrand and we again solve the problem using Pontryagin's principle. A special case of the optimal control problem is solved by transforming it into a linear complementarity problem. For the two-product problem we again present a simple algorithm that involves solving a sequence of small QP problems and also consider the case where the initial inventory levels are decision variables. Copyright © 2006 John Wiley & Sons, Ltd. [source] PAYING FOR LOYALTY: PRODUCT BUNDLING IN OLIGOPOLY,THE JOURNAL OF INDUSTRIAL ECONOMICS, Issue 1 2006JOSHUA S. GANS In recent times, pairs of retailers such as supermarket and retail gasoline chains have offered bundled discounts to customers who buy their respective product brands. These discounts are a fixed amount off the headline prices that allied brands continue to set independently. We show that a pair of firms can profit from offering a bundled discount to the detriment of other firms and consumers whose preferences are farther removed from the bundled brands. Indeed, when both pairs of firms negotiate bundling arrangements, there are no beneficiaries and consumers simply find themselves consuming a sub-optimal brand mix. [source] Optimal amount of monocyte chemoattractant protein-1 enhances antitumor effects of suicide gene therapy against hepatocellular carcinoma by M1 macrophage activationCANCER SCIENCE, Issue 10 2008Tomoya Tsuchiyama Suicide gene therapy combined with chemokines provides significant antitumor efficacy. Coexpression of suicide gene and monocyte chemoattractant protein-1 (MCP-1) increases antitumor effects in murine models of hepatocellular carcinoma (HCC) and colon cancer. However, it is unclear whether the doses administered achieved the maximum antitumor effects. We evaluated antitumor effects of various amounts of recombinant adenovirus vector (rAd) expressing MCP-1 in the presence of a suicide gene in a murine model of HCC. HCC cells were transplanted subcutaneously into BALB/c nude mice, and transduced with a fixed amount of Ad-tk harboring the suicide gene, HSV-tk, and various doses of Ad-MCP1 harboring MCP-1 (ratios of 1:1, 0.1:1, and 0.01:1 relative to Ad-tk). Growth of primary tumors was suppressed when treated with Ad-tk plus Ad-MCP1 (1:1 and 1:0.1) as compared with Ad-tk alone. The antitumor effects against tumor rechallenge tended to be high in the Ad-tk plus Ad-MCP1 group (1:0.1). The effects were dependent on production of Th1 type-cytokines. Delivery of an optimal amount of rAd expressing MCP-1 enhanced the antitumor effects of suicide gene therapy against HCC by M1 macrophage activation, suggesting that this is a plausible form of cancer gene therapy to prevent HCC progression and recurrence. (Cancer Sci 2008; 99: 2075,2082) [source] Additive Tuning of Redox Potential in Metallacarboranes by Sequential Halogen SubstitutionCHEMISTRY - A EUROPEAN JOURNAL, Issue 22 2010Patricia González-Cardoso Abstract The first artificially made set of electron acceptors is presented that are derived from a unique platform Cs[3,3,-Co(C2B9H11)2], for which the redox potential of each differs from its predecessor by a fixed amount. The sequence of electron acceptors is made by substituting one, two, or more hydrogen atoms by chlorine atoms, yielding Cs[3,3,-Co(C2B9H11,yCly)(C2B9H11,zClz)]. The higher the number of chlorine substituents, the more prone the platform is to be reduced. The effect is completely additive, so if a single substitution implies a reduction of 0.1,V of the redox potential of the parent complex, then ten substitutions imply a reduction of 1,V. [source] Home-based therapy with ready-to-use therapeutic food is of benefit to malnourished, HIV-infected Malawian childrenACTA PAEDIATRICA, Issue 2 2005MJ Ndekha Abstract Aim: To determine if home-based nutritional therapy will benefit a significant fraction of malnourished, HIV-infected Malawian children, and to determine if ready-to-use therapeutic food (RUTF) is more effective in home-based nutritional therapy than traditional foods. Methods: 93 HIV-positive children >1 y old discharged from the nutrition unit in Blantyre, Malawi were systematically allocated to one of three dietary regimens: RUTF, RUTF supplement or blended maize/soy flour. RUTF and maize/soy flour provided 730 kJ·kg,1·d,1, while the RUTF supplement provided a fixed amount of energy, 2100 kJ/d. These children did not receive antiretroviral chemotherapy. Children were followed fortnightly. Children completed the study when they reached 100% weight-for-height, relapsed or died. Outcomes were compared using regression modeling to account for differences in the severity of malnutrition between the dietary groups. Results: 52/93 (56%) of all children reached 100% weight-for-height. Regression modeling found that the children receiving RUTF gained weight more rapidly and were more likely to reach 100% weight-for-height than the other two dietary groups (p<0.05). Conclusion: More than half of malnourished, HIV-infected children not receiving antiretroviral chemotherapy benefit from home-based nutritional rehabilitation. Home-based therapy RUTF is associated with more rapid weight gain and a higher likelihood of reaching 100% weight-for-height. [source] | ||||||||||||||||