The first Joint Meeting of the Austrian and Swiss Operations Research Societies was held at the University of Technology in Vienna, Austria, from 22-24 September 1980. A selection of the papers then presented are published in this volume. The papers included provide a picture of Operations Research as a discipline comprehending various methods and models. The volume is divided into two parts. The first part contains papers on mathematical programming and optimal control theory. Moreover, two papers on decision and game theory are included as well as two on biomathematical to~ics. Being more heterogeneous, the second part, on stochastic models, includes such topics as queueing theory, econometrics and time series analysis. As a special feature of the symposium, a series of applications of OR models in energy planning were discussed, e.g., load and demand forecasting, power distribution and extension planning, reliability and work-safety, etc. These papers have been incorporated into parts one and two according to the models used. GUSTAV FEICHTINGER PETER !CALL Institut fUr Okonometrie und Institut fUr Operations Research und Operations Research mathematische Methoden der Wirtschafts- Technische UniversitHt wissenschaften Wien UniversitHt ZUrich November 198 I ix Gustav Feichtinger and Peter Kall (eds.), Operations Research in Progress, ix..

1: Mathematical Programming and Optimal Control Theory.- An Optimality Condition and its Application to Parametric Semi-Infinite Optimization.- The Choice of a Parameter in a Penalty Method.- Recent Results on ?-Conjugation and Nonconvex Optimization.- On Quantitative Stability of Point-to-Set-Mappings and the Rate of Convergence of Corresponding Algorithms.- On the Penalization Method in Convex Stochastic Programming.- A New Algorithm of Solving the Flow - Shop Problem.- On Dynamic Traffic Assignment.- On an Approximation Problem of Mechanical Structural Optimization.- Optimal Daily Scheduling of the Electricity Production in Hungary.- Power Distribution Planning and the Application of Linear Mixed-Integer Programming.- Optimal Flood Control by Reservoir Systems Using the Reduced Gradient Method.- Instant Optimization of Hydro Energy Storage Plants.- Dynamic Programming in Power System Extension Planning.- Some New Multicriteria Approaches.- Equilibrium Selection in a Wage Bargaining Situation with Incomplete Information.- Planning and Forecast Horizons in a Simple Wheat Trading Model.- Intertemporal Reversales of Environmental and Macroeconomic Policies.- Optimal Control of Concave Economic Models with two Control Instruments.- Optimal Control with Switching Dynamics.- Dynamic Systems with Several Decision-Makers.- Optimal Bimodal Harvest Policies in Age-Specific Bioeconomic Models.- Growth Rates, Optimal Harvesting and Related Topics in the Mass Rearing of Tsetse Flies.- The Release of Partly Fertile Males or Females in the Application of the Sterile-Insect Technique: Mathematical Analysis of the Hard-Release Strategy.- 2: Stochastic Models.- New Developments in Optimal Control of Queueing Systems.- Estimation and Control in a GI|M|1-System.- On Discriminatingamong Stochastic Models - A Survey.- Increasing the Work-Safety in Nuclear Power Plants through the Use of Preventive Maintenance Policies.- Recent Developments in Econometrics.- Slight Misspecifications of Linear Systems.- Local Sensitivity Analysis and Matrix Derivatives.- Analysis and Forecasting of Demand for Electricity Using Time Series Analysis.- Short Term Load Predication in Electric Power Systems.- Interactive Short-Term Load Forecasting.- Predicting the Demand for Electricity - An Application of Transfer Function Analysis.- Problems Associated with the Design of a Reliability Model in Electricity Industry.