Loss-Avoidance and Forward Induction in Experimental Coordination Games

We report experiments on how players select among multiple Pareto-ranked equilibria in a coordination game. Subjects initially choose inefficient equilibria. Charging a fee to play (which makes initial equilibria money-losing) creates coordination on better equilibria. When fees are optional, improved coordination is consistent with forward induction. But coordination improves even when subjects must pay the fee (forward induction does not apply). Subjects appear to use a "loss-avoidance" selection principle: they expect others to avoid strategies that always result in losses. Loss-avoidance implies that "mental accounting" of outcomes can affect choices in games

Equilibrium analysis of capacity allocation with demand competition

This article examines the capacity allocation decisions in a supply chain in which a supplier sells a common product to two retailers at a fixed wholesale price. The retailers order the supplier's product subject to an allocation mechanism preannounced by the supplier, and compete for the customer demand. We perform an equilibrium analysis of the retailers' ordering decisions under uniform and individually responsive allocations. Uniform allocation guarantees equilibrium orders, but is not necessarily truth inducing in the presence of demand competition. Further, we find that (1) neither the supplier nor either one of the retailers sees its profits necessarily increasing with the supplier's capacity, and the supplier may sell more with a lower capacity level, and (2) capacity allocation may not only affect the supply chain members' profits but also change the supply chain structure by driving a retailer out of the market. This article provides managerial insights on the capacity and ordering decisions for the supplier, the retailers, and the supply chain. © 2012 Wiley Periodicals, Inc. Naval Research Logistics, 2012Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/91147/1/21486_ftp.pd

A new process model for urban transport of food in the UK

Urbanisation is increasing at a rapid pace and one of the consequences of this trend is that more people live in cities, more people demand more products, and above all, more food needs to be transported to and distributed within the cities. With the advancement of new technologies and widespread use of mobile devices in the population, more and more people prefer to shop online, not just books, electronics, or fashion products, but food products as well, in particular the groceries. In this work, we focus on this growing challenge of food distribution in the cities, from the viewpoint of this emerging channel: home deliveries of online food purchases. Especially in the UK which is the second biggest online grocery market over the world, retailers are offering online shopping to their customers and then fulfil the home delivery using their own fleet. This poses challenges to retailers in terms of increased costs from providing a non-core service of distribution and logistics to end-consumers and the life in the cities in general in terms of increased carbon emissions and traffic. We design models that propose appropriate incentives to retailers to collaborate for the distribution of home deliveries. For this purpose, we initially investigate the current market structure and operations. Then, we test our logistics sharing models with empirical data from a retailer based in London to show the relevance of collaboration. Our results suggest that it is theoretically possible to collaborate and reduce economic, environmental, and social costs arising from the uncoordinated case; however, implementation of these ideas still pose a great challenge due to the extremely competitive nature of the food retail marke

Turbulence Model Comparison for Compact Plate Heat Exchanger Design Application.

In the framework of the Gas-Power Conversion System for the Advanced Sodium Technological Reactor for Industrial Demonstration (ASTRID) project design, works done at CEA are focused on the design of the sodium-gas heat exchanger. Compact plate heat exchangers are indicated as the most suitable technology for such applications. An innovative compact heat exchanger geometry is proposed in this paper: its innovationconsists increatinga 3D mixing flow. The proposed geometry has also very good mechanical resistance to high pressure gradients, being suitable for a large variety of flow applications. The flowfield inside such a channel is experimentally studied using the Laser Doppler Velocimetry (LDV) technique. The main velocity, the radial velocity as well as the Reynolds stressesare measured: data show the high level of flow mixing and the 3D flow pattern inside the channel. The experimental measurements are then used to validate turbulence models: in particular Reynolds-Averaged Navier-Stokes (RANS) equations are closed using both isotropic 2-equation isotropic eddy viscosity models and a Non-Linear Eddy Viscosity Model (NLEVM). Presented results represent the first step in the assessment of innovative high-performance compact plate heat exchangers that can be used to increase the plant efficiency as well as decrease the capital cost of the single component

Colgajo libre córtico-perióstico de la arteria genicular descendente en el tratamiento de la seudoartritis distal de tibia

Presentamos un caso de un varón de 35 años con pseudoartrosis aséptica de tibia distal con escaso defecto óseo, intervenido previamente mediante recambio del material de osteosíntesis e injerto de cresta iliaca, que fracasó. Tras estudio de las diferentes opciones de tratamiento, se le propuso estabilizar el foco mediante enclavado endomedular y aumentar la capacidad osteogénica con un colgajo córtico-perióstico de la arteria genicular descendente, según la técnica de Sakai. Discusión: El manejo terapéutico de la pseudoartrosis distal de tibia no está del todo resuelto. Cuando otras opciones no han sido efectivas, el clavo endomedular asociado al colgajo libre córtico-perióstico de la arteria genicular descendente puede ser una opción válida para el tratamiento. Esta técnica quirúrgica supone un trabajo coordinado entre los especialistas en traumatología y cirugía plástica.We present a case of 35 years old man presented with aseptic distal tibial nonunion without bone defect. Previous unsuccessful surgical attempt, consisting on revision of the internal fixation and iliac crest bone grafting, was performed. After studying the different treatment options, we suggested him to carry out an endomedular nail stabilization of the nonunion site in combination with a descending genicular corticoperiosteal free flap to provide osteogenetic enhancement, as described by Sakai. Discussion: The treatment protocol of the distal tibial nonunion still remains controversial. When other surgical attempts are unsuccessful, the combination of endomedular nailing and descending genicular corticoperiosteal free flap, may be useful. This surgical technique may require a coordinated work between orthopaedic and plastic surgeons

An experimental investigation of entry cost effects in sealed bid dollar auctions

Discussion paperIn numerous auction settings potential bidders incur costs to enter the auction. Such costs may potentially influence bidder’s behavior subsequently. In this paper we experimentally study the effect of entry costs on bidding and entry behavior, through a complete information common value auction. We run first and second price auctions both with and without entry costs. We find that with entry costs, players on average bid lower in first price auctions, while in second price auctions the average bids are higher, compared to bids in the corresponding no entry fee auctions.Author's draft issued as discussion paper. Final version published by Elsevier; available online at http://www.sciencedirect.com

Supplier-Buyer Negotiation Games: Equilibrium Conditions and Supply Chain Efficiency

In a decentralized supply chain, supplier–buyer negotiations have a dynamic aspect that requires both players to consider the impact of their decisions on future decisions made by their counterpart. The interaction generally couples strongly the price decision of the supplier and the quantity decision of the buyer. We propose a basic model for a repeated supplier–buyer interaction, during several rounds. In each round, the supplier first quotes a price, and the buyer places an order at that price. We find conditions for existence and uniqueness of a well-behaved subgame-perfect equilibrium in the dynamic game. When costs are stationary and there are no holding costs, we identify some demand distributions for which these conditions are met, examine the efficiency of the equilibrium, and show that, as the number of rounds increases, the profits of the supply chain increase towards the supply chain optimum. In contrast, when costs vary over time or holding costs are present, the benefit from multi-period interactions is reduced and after a finite number of time periods, supply chain profits stay constant even when the number of rounds increases

Robert Jones bandage pressure range assessment using a pressure mapping system and application to band calibration

International audienceThe Robert Jones bandage (RJ) is a widely used bandage among veterinary surgeons to maintain physiological position of the limbs. It is a 3-layer composite bandage, which realization involves the use of several types of bands in a specific arrangement to give the bandage all its properties. Its proper making is difficult and requires experience, as the bandage needs to be not too tight or not too loose. This issue is a recurrent matter with every type of compression bandage (Rimaud et al. 2014). For the realization of a RJ, various types of bands can be used, depending on the surgeon but each layer has its own function that cannot be changed.The purpose of this study is to measure the pressure under a RJ bandage with a pressure mapping system and to evaluate the properties of some commonly used bands. The final application of these results is to propose a band calibration system to apply the correct pressure as a function of the band’s deformation

Identification of unique reciprocal and non reciprocal cross packaging relationships between HIV-1, HIV-2 and SIV reveals an efficient SIV/HIV-2 lentiviral vector system with highly favourable features for in vivo testing and clinical usage.

BACKGROUND: Lentiviral vectors have shown immense promise as vehicles for gene delivery to non-dividing cells particularly to cells of the central nervous system (CNS). Improvements in the biosafety of viral vectors are paramount as lentiviral vectors move into human clinical trials. This study investigates the packaging relationship between gene transfer (vector) and Gag-Pol expression constructs of HIV-1, HIV-2 and SIV. Cross-packaged vectors expressing GFP were assessed for RNA packaging, viral vector titre and their ability to transduce rat primary glial cell cultures and human neural stem cells. RESULTS: HIV-1 Gag-Pol demonstrated the ability to cross package both HIV-2 and SIV gene transfer vectors. However both HIV-2 and SIV Gag-Pol showed a reduced ability to package HIV-1 vector RNA with no significant gene transfer to target cells. An unexpected packaging relationship was found to exist between HIV-2 and SIV with SIV Gag-Pol able to package HIV-2 vector RNA and transduce dividing SV2T cells and CNS cell cultures with an efficiency equivalent to the homologous HIV-1 vector however HIV-2 was unable to deliver SIV based vectors. CONCLUSION: This new non-reciprocal cross packaging relationship between SIV and HIV-2 provides a novel way of significantly increasing bio-safety with a reduced sequence homology between the HIV-2 gene transfer vector and the SIV Gag-Pol construct thus ensuring that vector RNA packaging is unidirectional.RIGHTS : This article is licensed under the BioMed Central licence at http://www.biomedcentral.com/about/license which is similar to the 'Creative Commons Attribution Licence'. In brief you may : copy, distribute, and display the work; make derivative works; or make commercial use of the work - under the following conditions: the original author must be given credit; for any reuse or distribution, it must be made clear to others what the license terms of this work are