Dynamic Pricing of Substitutable Products in the Presence of Capacity Flexibility

Firms that offer multiple products are often susceptible to periods of inventory mismatches where one product may face shortages while the other has excess inventories. In this paper, we study a joint implementation of price- and capacity-based substitution mechanisms to alleviate the level of such inventory disparities. We consider a firm producing substitutable products via a capacity portfolio consisting of both product-dedicated and flexible resources and characterize the structure of the optimal production and pricing decisions. We then explore how changes in various problem parameters affect the optimal policy structure. We show that the availability of a flexible resource helps maintain stable price differences across products over time even though the price of each product may fluctuate over time. This result has favorable ramifications from a marketing standpoint because it suggests that even when a firm applies a dynamic pricing strategy, it may still establish consistent price positioning among multiple products if it can employ a flexible replenishment resource. We provide numerical examples for the price stabilization effect and discuss extensions of our results to a more general multiple product setting

Analysis of tip-sample interaction in tapping-mode atomic force microscope using an electrical circuit simulator

Cataloged from PDF version of article.We present a mechanical model for the atomic force microscope tip tapping on a sample. The model treats the tip as a forced oscillator and the sample as an elasticmaterial with adhesiveproperties. It is possible to transform the model into an electrical circuit, which offers a way of simulating the problem with an electrical circuit simulator. Also, the model predicts the energy dissipation during the tip–sample interaction. We briefly discuss the model and give some simulation results to promote an understanding of energy dissipation in a tapping mode. © 2001 American Institute of Physic

Dynamic Pricing and Replenishment with Customer Upgrades

We study a joint implementation of price‐ and availability‐based product substitution to better match demand and constrained supply across vertically differentiated products. Our study is motivated by firms that utilize dynamic pricing as well as customer upgrades, as ex ante and ex post mechanisms, respectively, to mitigate inventory mismatches. To gain insight into how offering product upgrades impacts optimal price selection, we formulate a multiple period, nested two‐stage model where the firm first sets prices and replenishment levels for each product while the demand is still uncertain, and after observing the demand, decides how many (if any) of the customers to upgrade to a higher quality product. We characterize the structure of the optimal upgrade, pricing and replenishment policies and find that firms having greater flexibility to offer product upgrades can restrain their reliance on dynamic pricing, enabling them to better protect the price differentiation between the products. We also show how the quality differential between the products or changes in the replenishment cost structures influence the optimal policy. Using insights gained from the optimal policy structure, we construct a heuristic policy and find that it performs well across various parameter values. Finally, we consider an extension in which the firm dynamically sets upgrade fees in each period. Our results overall help further our understanding of the intricate relationship among a firm's decisions on pricing, replenishment, and product upgrades in an effort to better match demand and constrained supply

Joint Interference Alignment and Bi-Directional Scheduling for MIMO Two-Way Multi-Link Networks

By means of the emerging technique of dynamic Time Division Duplex (TDD), the switching point between uplink and downlink transmissions can be optimized across a multi-cell system in order to reduce the impact of inter-cell interference. It has been recently recognized that optimizing also the order in which uplink and downlink transmissions, or more generally the two directions of a two-way link, are scheduled can lead to significant benefits in terms of interference reduction. In this work, the optimization of bi-directional scheduling is investigated in conjunction with the design of linear precoding and equalization for a general multi-link MIMO two-way system. A simple algorithm is proposed that performs the joint optimization of the ordering of the transmissions in the two directions of the two-way links and of the linear transceivers, with the aim of minimizing the interference leakage power. Numerical results demonstrate the effectiveness of the proposed strategy.Comment: To be presented at ICC 2015, 6 pages, 7 figure

Bubbly cavitating flow generation and investigation of its erosional nature for biomedical applications

This paper was presented at the 2nd Micro and Nano Flows Conference (MNF2009), which was held at Brunel University, West London, UK. The conference was organised by Brunel University and supported by the Institution of Mechanical Engineers, IPEM, the Italian Union of Thermofluid dynamics, the Process Intensification Network, HEXAG - the Heat Exchange Action Group and the Institute of Mathematics and its Applications.The paper presents a study of the generation of hydrodynamic bubbly cavitation in microchannels to investigate the destructive energy output resulting from this phenomenon and its potential use in biomedical applications. The research performed in this study includes the experimental results from bubbly cavitation experiments and the findings showing the destructive effects of bubbly cavitating flow on selected specimens and cells. The bubbles caused by hydrodynamic cavitation are highly destructive at the surfaces of the target medium on which they are carefully focused. The resulting destructive energy output could be effectively used for good means such as destroying kidney stones or killing infected cancer cells. Motivated by this potential, the cavitation damage (material removal) to cancerous cells and chalk pieces having similar material properties as calcium phosphate in human bones was investigated. Also the potential of hydrodynamic bubbly cavitation generated at the microscale for biomedical treatments was revealed using the microchannel configuration of a microorifice (with an inner diameter of 0.147 mm and a length of 1.52cm).This work was supported by Sabancı University Internal Grant for Research Program under Grant FRG-C47004

Simulation of higher harmonics generation in tapping-mode atomic force microscopy

Cataloged from PDF version of article.In tapping-mode atomic force microscopy, nonlinear tip–sample interactions give rise to higher harmonics of the cantilever vibration. We present an electrical circuit to model the atomic force microscope cantilever with its first three flexural eigenmodes. An electrical circuit simulator is used to simulate the tapping-mode operation. Amplitude and phase responses of the third flexural eigenmode are obtained for different sample properties. It is found that amplitude and phase of higher harmonics depend highly on sample properties. © 2001 American Institute of Physic

A laboratory study of the effects of water dissolved gypsum application on hydraulic conductivity of saline-sodic soil under intermittent ponding conditions

peer-reviewedReclamation of saline-sodic soils has great importance in agricultural management. The objective of this study was to evaluate the effectiveness of the methods used to apply water and gypsum on hydraulic conductivity of a saline-sodic soil with an electrical conductivity of 28 dS/m and exchangeable sodium percentage of 46%. The experiment was conducted under laboratory conditions using disturbed and non-cropped soil columns. A total of 45 cm of water was applied to each column with 3, 6, or 9 separate water applications. Finely ground gypsum (< 0.5 mm maximum particle diameter) was either incorporated into the surface 2 to 3 cm of soil or was dissolved into the leaching water at a rate corresponding to 3.82 t/ha. Six or nine separate water applications of gypsum dissolved into leaching water significantly increased hydraulic conductivity (P < 0.01). Soil hydraulic conductivity increased (P < 0.01) with depth at separate applications of gypsum

Water and energy-based optimisation of a “MiniCity”: A system dynamics approach

Urban sprawls in Australia and several countries around the world have introduced a number of social, economic, and environmental issues for residents and urban planners, highlighting the need for new urban development concepts. In recent years, the concept of a vertical sprawl called "MiniCity" has been presented. The objective of a successful "MiniCity", compared to traditional high-rises, is to be as self-sufficient and self-contained as possible; whilst also minimising issues such as car dependency, loss of agricultural land and natural habitats, water and air pollution, and poorer health and wellbeing, which are common for residents in low-density, low-rise areas and developments. To date however, the viability of a MiniCity has yet to be properly addressed. Arguably, the predominant needs for a community are water, energy and food. In this research study, a System Dynamics model was developed to simulate supply and demand of the water and energy systems, as well as their interaction, for a hypothetical MiniCity located in South-East Queensland, Australia. The models were conceptualised based on expert knowledge, with data and equations collected from local Gold Coast sources and from the literature. Preliminary results show the complex, but expected, dynamics and interactions between the two systems, and their dependence to critical input parameters, such as climate data, roof area, number of floors, to name a few. Future work will focus on adding other critical modelling components such as food production and thus analyse the water-energy-food nexus. The final, validated model will allow the optimisation of critical MiniCity parameters and the identification of suitable locations that can maximise the socio-economic and environmental viability of the MiniCity.Full Tex