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We develop a price competition model for a new supply chain that competes in a market comprised of some rival supply chains. The new supply chain has one risk-neutral manufacturer and one risk-averse retailer in which the manufacturer is a leader and retailer is a follower. The manufacturer pays a fraction of the risk cost (caused by demand uncertainty) to the retailer. We apply this competitive model to a real-world case in a supply chain under uncertain environment and obtain the optimal wholesale and retail prices. We show that our obtained prices are better than the existing wholesale and retail prices and admit more profits for both manufacturer and retailer and generally for the entire supply chain. Also, using this case, the effects of risk sensitivity of retailer and fraction of risk cost shared by manufacturer in the total risk cost on the new supply chain’s optimal wholesale and retail prices and profits are illustrated.

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We develop a new coordination contract of manufacturer-retailer in a distribution system. A revenue sharing contract based on retail price is modelled, which is more practical to handle channel conflict. We also integrate two concepts of CSR (Corporate Sociality Responsible) and Semi-TDPD (Semi Third Degree Price Discrimination) into our model. Semi-TDPD strategy makes it possible to exploit the opportunity of customer behavior, by adopting a price discrimination strategy. According to this strategy, some customers who cannot or are not willing to pay the posted price, are allowed to purchase at lower prices through bargaining. To illustrate the proposed approach, we present some numerical examples. Through these examples, we investigate the impact of CSR and Semi-TDPD on decisions and also the good performance of this coordination.

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The purpose of the present study was to determine the effect of education using mathematical games on learning and retention of third grade elementary students. This research in terms of purpose was conducted as an applied research. Also in terms of implementation and data collection method, the quasi-experimental method and pre-test-post-test design with a control group was used. The statistical population of the present study included all 6,500 female third grade elementary school students in District 1 of Mashhad- Iran. The sampling method in this study was in convenience form that included 60 students and were selected through convenience sampling method, thus two classes with 30 female students for each classroom were selected among the elementary girls' schools in District 1 of Mashhad- Iran. In order to collect data, two researcher-made tests of learning and retention were used, the validity of which was confirmed by experts and its reliability was calculated based on Cronbach's alpha equal to 0.81 and 0.83, respectively. Multivariate analysis of covariance (MANCOVA) was used in order to test the hypotheses inferential analysis. The results of data analysis showed that math games are effective on students math both learning and retention (P <0.01). Therefore, it can be concluded that education using math games is effective and has increased students' learning and retention.
 

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In this paper the pricing of reverse products in a two-level closed-loop supply chain is considered and a game theory approach is used to solve it. Pricing is a sensitive and vital issue for businesses. In the market of reverse products, this issue will be much more difficult and complex due to difficulties associated with collecting and re-manufacturing processes. On the other hand, the use of the internet and direct channels for collecting products from customers alongside traditional retailers is an important issue that requires management and coordination. The proposed price for buying second-hand and defective products from customers should be high enough to convince them that returning the products has more benefits than discarding or keeping them at home. At the same time, the price should be low enough to make it economically viable for producers to carry out the repair and re-manufacturing operations and resell them in the direct supply chain for the producer. The use of game theory, where the decisions of one player affect the decisions and outcomes of other players as well as their outcomes, is a suitable method for solving the problem of pricing reverse products in a two-level closed-loop supply chain