Browsing by Subject "Coordination"

Now showing 1 - 5 of 5

Open Access
An Elasticity Approach to the Newsvendor with Price Sensitive Demand
(INFORMS, 2011-04) Kocabiyikoglu, A.; Popescu, I.
We introduce a measure of elasticity of stochastic demand, called the elasticity of the lost-sales rate, which offers a unifying perspective on the well-known newsvendor with pricing problem. This new concept provides a framework to characterize structural results for coordinated and uncoordinated pricing and inventory strategies. Concavity and submodularity of the profit function, as well as sensitivity properties of the optimal inventory and price policies, are characterized by monotonicity conditions, or bounds, on the elasticity of the lost-sales rate. These elasticity conditions are satisfied by most relevant demand models in the marketing and operations literature. Our results unify and complement previous work on price-setting newsvendor models and provide a new tool for researchers modeling stochastic price-sensitive demand in other contexts.
Open Access
Innovation in mixed market economies: the case of METU technopolis in Turkey
(2023-07) Dervişler, Olgu
This dissertation examines the conditions under which innovation would be possible in a Mixed Market Economy, also known as the Mediterranean Market Economy, (MME) at the sub-national level through covering a case study which was conducted in METU Technopolis of Turkey. The Varieties of Capitalism (VoC) literature identifies two ideal-typical market economies which are Liberal Market Economies (LMEs) and Coordinated Market Economies (CMEs), yet MMEs are regarded as the third category. Due to a lack of strong institutional complementarities and macro-level coordination, this market type is regarded as disadvantageous to have high innovation performance. However, Systems of Innovation (SI) literature suggests that independent of macro-level coordination and institutional complementarities, owing to local and place-specific factors, high innovation performance would still be possible in an MME. In this context, within the framework of this dissertation, seventeen semi-structured interviews were conducted with the firms in METU Technopolis to understand the conditions which would lead to the innovation outcome in an MME. This study demonstrates that in a sub-national innovation system of an MME, both macro-level and sub-national level factors have an impact on the innovation outcome, at various levels. Despite the fact that macro-level institutions have a complementary role in innovation performance when it comes to particular competencies to overcome the coordination problems in the market, firms have difficulties. However, as findings demonstrate, thanks to place-specific factors, local resources, and a high level of interaction with stakeholders at the sub-national level, firms in this ecosystem produce innovation.
Open Access
Inventory and coordination issues with two substitutable products
(Elsevier, 2010-03) Gürler, Ü.; Yılmaz, A.
This study considers a two level supply chain in a newsboy setting with two substitutable products. Demands for the two products are assumed independent as long as both are available. If, however, a product stocks out, some of its demand is transferred to the available one with a known probability which ultimately creates a dependence on the amount of purchased items. The retailer is allowed to return some or all of the unsold products to the manufacturer with some credit. The expected chain profit, the retailer’s and the manufacturer’s profit expressions are derived under general conditions. Special cases are inspected to investigate the conditions under which channel coordination is achieved. It is demonstrated that channel coordination can not be achieved if unlimited returns are allowed with full credit, a result that agrees with the findings of Pasternak [B.A. Pasternack, Optimal pricing and return policies for perishable commodities, Market. Sci. 4 (1985) 166– 176] for the single item case. For the cases of unlimited returns with partial credit, the conditions for coordination are derived for one way full substitutions. For exponential demand explicit expressions for the channel and retailer’s expected profit functions are provided.
Open Access
Pricing and revenue management: the value of coordination
(INFORMS Inst.for Operations Res.and the Management Sciences, 2014) Kocabiyikoǧlu, A.; Popescu, I.; Stefanescu, C.
The integration of systems for pricing and revenue management must trade off potential revenue gains against significant practical and technical challenges. This dilemma motivates us to investigate the value of coordinating decisions on prices and capacity allocation in a stylized setting. We propose two pairs of sequential policies for making static decisions - on pricing and revenue management - that differ in their degree of integration (hierarchical versus coordinated) and their pricing inputs (deterministic versus stochastic). For a large class of stochastic, price-dependent demand models, we prove that these four heuristics admit tractable solutions satisfying intuitive sensitivity properties. We further evaluate numerically the performance of these policies relative to a fully coordinated model, which is generally intractable. We find it interesting that near-optimal performance is usually achieved by a simple hierarchical policy that sets prices first, based on a nonnested stochastic model, and then uses these prices to optimize nested capacity allocation. This tractable policy largely outperforms its counterpart based on a deterministic pricing model. Jointly optimizing price and allocation decisions for the high-end segment improves performance, but the largest revenue benefits stem from adjusting prices to account for demand risk.
Open Access
The pursuit of an ideal coordination environment of the catalytic site for water splitting
(2022-07) Ahmad, Aliyu Aremu
The construction of catalysts from cheap materials and exquisite tuning of the coordination environment of the active site is pivotal to the development of a highly active sustainable water-splitting catalyst. Although recent years have seen tremendous growth in the application of Prussian Blue Analogues (PBAs) as non-noble catalysts for water splitting, the effect of the structural coordination of the active sites on the activity of a Prussian blue (PB) catalyst is yet to be explored. Herein, using two simple synthetic strategies, we show that manipulating the coordination environment of the catalytic sites affects the morphology, electronic properties, and eventually the catalytic activity of PBAs. Moreover, this study mimics natural photosynthesis by using solar light as an energy source. First, we demonstrate that the water oxidation activity and stability of a Co–Fe PBA can be tuned by coordinating bidentate capping ligands to the catalytic cobalt sites. Structural characterization studies reveal that the ligand decorated structures are of relatively lower dimensionality and they retained their network structures even after photocatalysis. Photocatalytic water oxidation studies indicate that coordination of one equivalent ligand group to the catalytic cobalt sites (CoL–Fe) results in an enhancement of about 50 times in upper-bound turnover frequency (TOF), while coordination of two equivalent ligand groups to the catalytic cobalt sites (CoL2–Fe) lead to an inactivity, which is attributed to the lack of coordination of water molecules to the catalytic sites. In addition, computational studies support experimental observation by showing that bidentate pyridyl groups enhance the susceptibility of the rate-determining Co(IV)-oxo species to the nucleophilic water attack during the critical O−O bond formation. We found in the second study that the replacement of [Fe(CN)6]3− unit with a square planar [Ni(CN)4]2− building block drastically changes the electronic environment and catalytic properties by converting the PB structure from 3D to a 2D layered structure, and we utilized it for the first time for photocatalytic hydrogen evolution reaction. We synthesized a 2D cyanide-coordination compound [Co–Ni] and performed a complete structural and morphological characterization that fully supports our synthetic claim. Relying on its exposed facets, layered morphology, and abundant surface-active sites, [Co–Ni] can efficiently convert water and sunlight to H2 in the presence of a ruthenium photosensitizer with an optimal evolution rate of 30,029 μmol g−1 h −1, greatly exceeding that of 3D PBA frameworks and top-ranked catalysts operating under the same condition. Furthermore, [Co–Ni] retains its structural integrity throughout a 6-hour photocatalytic cycle, which is confirmed by XPS, XRD and Infrared analysis. Overall, these two strategies signify the importance of the coordination environment of the active sites in exploiting structure/morphology and optimizing the activity of the catalyst.