Browsing by Subject "Merging"

Now showing 1 - 3 of 3

Open Access
Active pixel merging on hypercube multicomputers
(Springer, Berlin, Heidelberg, 1996) Kurç, Tahsin M.; Aykanat, Cevdet; Özgüç, Bülent
This paper presents algorithms developed for pixel merging phase of object-space parallel polygon rendering on hypercube-connected multicomputers. These algorithms reduce volume of communication in pixel merging phase by only exchanging local foremost pixels. In order to avoid message fragmentation, local foremost pixels should be stored in consecutive memory locations. An algorithm, called modified seanline z-buffer, is proposed to store local foremost pixels efficiently. This algorithm also avoids the initialization of scanline z-buffer for each scanline on the screen. Good processor utilization is achieved by subdividing the image-space among the processors in pixel merging phase. Efficient algorithms for load balancing in the pixel merging phase are also proposed and presented. Experimental results obtained on a 16-processor Intel's iPSC/2 hypercube multicomputer are presented. © Springer-Verlag Berlin Heidelberg 1996.
Open Access
Cournot competition in networked markets
(ACM, 2014) Bimpikis, K.; Ehsani, S.; İlkılıç, Rahmi
The paper considers a model of competition among firms that produce a homogeneous good in a networked environment. A bipartite graph determines which subset of markets a firm can supply to. Firms compete a la Cournot and decide how to allocate their production output to the markets they are directly connected to. We assume that markets have inverse linear demand and firms have quadratic production costs. First, we show that the resulting Cournot game has a unique equilibrium for any given network and provide a characterization of the production quantities at equilibrium. Our results identify a close connection between the equilibrium outcome and supply paths in the underlying network structure. In particular, we show that whether two firms see their output in different markets as strategic substitutes or complements depends critically on the paths between those markets in the line graph induced by the original bipartite network. Armed with a characterization of the equilibrium supply decisions, we explore the effect of changes in the network structure on firms' profits and consumer welfare. First, we study the question of a firm entering a new market. We show that entry may not be beneficial for either the firm or the consumers as such a move affects the entire vector of production quantities. The firm might face a more aggressive competition in its original markets due to its entry to a new market. Moreover, the effect on other firms and consumers also depends on their location in the network. This is in stark contrast with standard results in Cournot oligopoly where entry implies more competition in the market and thus higher consumer welfare. Similarly, the effect of a merger between two firms on profits and overall welfare largely depends on the structure of competition in the original Cournot market. In particular, we show that insights from analyzing mergers in a single market do not carry over in a networked environment. Market concentration indices are insufficient to correctly account for the network effect of a merger and one should not restrict attention to the set of markets that the firms participating in the merger supply to. Finally, we study the operations of a cartel including the entire set of firms. We show that the cartel maximizes its profits by appropriately segmenting the markets among its members so that a firm supplies solely to the ones allocated to it, and we provide an algorithm that computes the optimal production quantities for each firm in the cartel. © 2014 Authors.
Open Access
Inventory performance with pooling: evidence from mergers and acquisitions
(Elsevier, 2015) Çömez-Dolgan, N.; Tanyeri B.
Theoretical studies show that compared to decentralized inventory management, (i) pooling inventories for different demand sources decreases the optimal safety stock, which in turn decreases inventory costs and (ii) the decrease in stock is related to the correlation between the different demand sources and variabilities of demands. Mergers and acquisitions (M&A) provide a business context to investigate the effects of correlation and variability of the merging firms' demands on potential improvements in inventory performance through inventory pooling. While merging firms may not fully centralize their inventory decisions, the coordination of inventory and supply chain decisions may result in synergies. Using firm-level data for 270 same-industry mergers carried out in U.S. between 1981 and 2009, we find that the inventory turnover of bidder and target firms improves (relative to firms in their industry) following the successful completion of mergers. The improvement in turnover is especially pronounced in deals where the demand of bidder and target firms are negatively correlated prior to the merger. Our results provide novel empirical support for the predictions of theoretical models on inventory economies in M&A.