A numerical approach for 3D manufacturing tolerances synthesis

Making a product conform to the functional requirements indicated by the customer suppose to be able to manage the manufacturing process chosen to realise the parts. A simulation step is generally performed to verify that the expected generated deviations fit with these requirements. It is then necessary to assess the actual deviations of the process in progress. This is usually done by the verification of the conformity of the workpiece to manufacturing tolerances at the end of each set-up. It is thus necessary to determine these manufacturing tolerances. This step is called "manufacturing tolerance synthesis". In this paper, a numerical method is proposed to perform 3D manufacturing tolerances synthesis. This method uses the result of the numerical analysis of tolerances to determine influent mall displacement of surfaces. These displacements are described by small displacements torsors. An algorithm is then proposed to determine suitable ISO manufacturing tolerances

Equilibrium Storage in a Markov Economy

We model an economy that alternates randomly between abundance and scarcity episodes. We develop an original method to characterize in detail the structure of the Markovian competitive equilibrium. Accumulation and drainage of stocks are the main focuses. Economically appealing comparative statics results are proved. We also characterize stationary distribution of states. We extend the model to discuss price stabilization policies, injection and release costs, and limited storage capacity. Overall, the analysis delineates the notion of “flexible economy.”Price stabilization; strategic stocks; supply risk

Optimal Liquidity Management and Hedging in the presence of a non predictable investment opportunity

In this paper, we develop a dynamic model that captures the interaction between the cash reserves, the risk management policy and the profitability of a non-predictable irreversible investment opportunity. We consider a firm that has assets in place generating a stochastic cash- ow stream. The firm has a non-predictable growth opportunity to expand its operation size by paying a sunk cost. When the opportunity is available, the firm can finance it either by cash or by costly equity issuance. We provide an explicit characterization of the firm strategy in terms of investment, hedging, equity issuance and dividend distribution.

The signaling effect of tax policy.

The paper focuses on the signaling value of a tax when agents are less informed than the government on the effect of their consumption. The policy making process is analyzed as a game in which the government wants to influence consumers' behaviors through tax policy, consumers being rational and Bayesian. The marginal cost of public funds induces the government to provide biased information to pursue budgetary objectives. We analyze the tax distortion that is required for credibility.tax policy; marginal cost of public funds; information bias; signaling;

Risk Aversion and the Value of Risk to Life.

The standard literature on the value of life relies on Yaari’s (1965) model, which includes an implicit assumption of risk neutrality with respect to life duration. To overpass this limitation, we extend the theory to a simple variety of nonadditively separable preferences. The enlargement we propose is relevant for the evaluation of life-saving programs: current practice, we estimate, puts too little weight on mortality risk reduction of the young. Our correction exceeds in magnitude that introduced by the switch from the notion of number of lives saved to the notion of years of life saved.Lifecycle Behavior; Life Insurance; Value of Statistical Life; Cost-Benefit Analysis;

Risk Aversion and the Value of Risk to Life

The standard literature on the value of life relies on Yaari’s (1965) model, which includes an implicit assumption of risk neutrality with respect to life duration. To overpass this limitation, we extend the theory to a simple variety of nonadditively separable preferences. The enlargement we propose is relevant for the evaluation of life-saving programs: current practice, we estimate, puts too little weight on mortality risk reduction of the young. Our correction exceeds in magnitude that introduced by the switch from the notion of number of lives saved to the notion of years of life saved.Value of Statistical Life; Lifecycle Behavior; Cost-benefit Analysis

Risk Aversion and the Value of Risk to Life

The standard literature on the value of life relies on Yaari’s (1965) model, which includes an implicit assumption of risk neutrality with respect to life duration. To overpass this limitation, we extend the theory to a simple variety of preferences which are not necessarily additively separable. The enlargement we propose is relevant for the evaluation of life-saving programs: current practice, we estimate, puts too little weight on mortality risk reduction of the young. Our correction exceeds in magnitude that introduced by the switch from the notion of number of lives saved to the notion of years of life saved.Value of Statistical Life; Lifecycle Behavior; Cost-benefit Analysis

On the value of optimal stopping games

We show, under weaker assumptions than in the previous literature, that a perpetual optimal stopping game always has a value. We also show that there exists an optimal stopping time for the seller, but not necessarily for the buyer. Moreover, conditions are provided under which the existence of an optimal stopping time for the buyer is guaranteed. The results are illustrated explicitly in two examples.Comment: Published at http://dx.doi.org/10.1214/105051606000000204 in the Annals of Applied Probability (http://www.imstat.org/aap/) by the Institute of Mathematical Statistics (http://www.imstat.org