Dynamic control mechanisms for revenue management with flexible products

Revenue management with flexible products has experienced a growing interest in the academic literature within the last few years. Flexible products allow supply-side substitution between resources and can therefore help to maximize overall revenue as well as capacity utilization in markets with highly uncertain demand. This paper addresses the question of how the mathematical models which have been developed for capacity control with flexible products should be used over time to exploit the substitution opportunities, while keeping practical applicability in mind. Several dynamic control mechanisms are proposed, each of which makes use of the flexibility to a different extent. A comprehensive computational study shows the potential of the different approaches by revealing their strengths and weaknesses.     

Dem Himmel entgegen – Klimadesign für den Federation Tower Moskau

Skywards – climate design for the Moscow Federation Tower. Advanced simulation tools were used in developing the climate design for the roof covering the taller of the two blocks at Moscow's Federation Tower. The all‐glass roof space at a height of 365 m is designed to accommodate the finest and most exclusive hotel areas. Several restaurants, bars and lounges and a Sky Dance Club will offer entertainment and fabulous views across the whole city. Simulations were used to develop and verify a design that ensures thermal comfort taking into account architectural, climate and utilisation requirements. The structure and the building services were simulated based on a 3D model, and simulations were carried out for summer and winter scenarios. This paper describes the design process including load calculations and the development and assessment of the climate design by means of simulation.     

Trust and Social Control: Sources of Cooperation,Performance, and Stability in Informal Value Transfer Systems

Computational Economics - We study the functioning of informal value transfer systems through the example of Hawala. By complementing the institutional theory with computational experiments that...     

A model-based approximation of opportunity cost for dynamic pricing in attended home delivery

OR Spectrum - For online retailers with attended home delivery business models, the decisive factor for promising dynamic time slot pricing decisions is the quality of the opportunity cost...     

Analysis of Subcycle Electro-Optic Sampling Without Background

Journal of Infrared, Millimeter, and Terahertz Waves - We explore background-free options to detect mid-infrared (MIR) electric transients. The MIR field and a near-infrared probe interact via sum-...     

Curing of polyimides

The imidization of films of the polyamic acid obtained from reaction of pyromellitic dianhydride (PMDA) with oxydianiline (ODA) was studied by dynamic mechanical thermal analysis (with the Polymer Labs DMTA), Two process regions are observed. The first process is characterized by decomplexation of the NMP/polyamic acid complex, plasticization, and imidization. The heating rate determines the character of the first process. At high temperatures (above 300°C) the second process becomes apparent. It is connected to the increase in chain mobility at these temperatures which allow molecular packing processes (densification, ordering) to occur. The ordering leads to an increase of the storage modulus. The particular transition temperature increases with annealing time.     

Optimized Sustainable Groundwater Extraction Management: General Approach and Application to the City of Lucknow, India

In rapidly developing urban areas of emerging countries, increased water demand has led to enormous groundwater withdrawal, calling out for sustainable groundwater management. We suggest implementing a sustainable pumping rate concept based on numerical modeling of the managed aquifer. Sustainability is achieved by constraints regarding (1) a minimum groundwater discharge rate to gaining rivers (ecological constraint) and (2) a maximum drawdown along the city boundaries (social constraints) to prevent excessive groundwater depletion in the neighboring peri-urban and rural areas. The total groundwater extraction is maximized subject to these constraints, leading to specific extraction patterns throughout the city, depending upon the values set for the constraints. The optimization is performed by linear programming. For a given extraction rate, the two constraints can be traded off by the groundwater manager, causing different wells to be activated or deactivated. We demonstrate the applicability of the methodology by the example of the city of Lucknow, India, but it can be transferred to other cities facing conflicts of managing groundwater resources.