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排序方式: 共有1318条查询结果,搜索用时 31 毫秒
1.
This paper analyzes transmission system operator (TSO)-host community negotiations over an efficient and socially-optimal compensation payment for the installation of new electric power transmission lines. We consider that the TSO has an incentive to negotiate over a transfer that will become a function of final demand. We thus develop a bargaining game within a vertical relationship framework to include the distribution system operator (DSO) and the end-users at the downside of the bargaining problem. We determine the equilibrium of the game, for three negotiation protocols (sequential, bilateral, and multilateral) as an alternative to the non-cooperative situation. We show that when the number of municipalities involved in the process is higher than 5, the multilateral bargaining procedure is the most profitable for all agents, including the municipalities. Inversely, when the number of municipalities is lower than 5, different cases can arise. A single municipality will prefer the non-cooperative outcome while municipalities will prefer the sequential case when there are 2 or the bilateral case when there are 3 or 4. However, from the TSO standpoint and for the society, multilateral negotiations are always the best outcome. 相似文献
2.
This paper examines the factors behind export diversification in oil countries. Specifically, we investigate the impact of oil booms on export diversification through an empirical framework. The paper finds that economy's export structure before the oil boom determines whether oil windfalls might affect the diversification process. Thus, an oil boom negatively affects export diversification only if countries initially exhibit low levels of diversification. In countries with a high level of diversification before the boom, an oil boom has no impact on diversification. These results are based on a large sample of 134 countries, and are robust to various sensitivity analyses. They are corroborated with data from the manufacturing sector which show that oil booms only reduce diversification in countries with a small manufacturing sector prior to the boom. 相似文献
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4.
The diffusion of solutes through milk and milk-derived media (i.e. dairy systems) is an important factor in the transformation and stabilization of dairy products. In several polymer systems, the diffusion of solutes largely depends on the microstructure within the material. The aim of this work was to establish how the diffusion of solutes is affected by the microstructure of dairy systems. Diffusion measurements were carried out using the technique of fluorescence recovery after photobleaching (FRAP). Diffusion coefficients of a range of 8 fluorescein isothiocyanate (FITC)–dextrans (molecular weights from 4 to 2000 kDa) were measured in dairy systems. These systems had the same casein concentration (130 g kg− 1) and water activity but their microstructure had been altered by different treatments: heat-treatment and rennet-induced coagulation. Microstructural parameters of these systems were estimated by the image analysis of transmission electron microscopy (TEM) micrographs. The results showed that the diffusion of solutes was affected by the microstructure of dairy systems. The application of heat-treatment hindered the diffusion of all solutes (irrespective of molecular weight), whereas rennet coagulation only increased the diffusion of the larger solute molecules (> 20 kDa). At the microscopic scale, the diffusion of solutes in dairy systems was mainly explained by both the pore size within the structure and by the interface area between the solute molecules and the surrounding matrix. Larger solutes diffused faster in dairy systems with larger pore sizes and less interface area. 相似文献
5.
Dreissenid mussel veligers compose a substantial component of pelagic biomass in the Great Lakes, yet their dynamics are poorly understood. To evaluate seasonal, spatial, and inter-annual variation in veliger density, we used a 64-μm mesh plankton net (2008, 2013–2016) and a 153-μm mesh plankton net (2007–2016) to collect dreissenid veligers at nearshore (15–25?m depth), transitional (45?m) and offshore (93–110?m) sites in southeast Lake Michigan during March–December. We also evaluated trends in density of recently settled mussels relative to veliger abundance and the density of the standing stock of adult mussels. Veliger density peaked during both summer and fall at all sites, but peak densities in summer were generally higher nearshore, whereas peak densities in the fall were generally higher offshore. The density of veligers in the 153-μm net was overall 28% of that in the 64-μm net, but there was high variability in this comparison among months. Smaller veligers were much more abundant in the 64-μm net, but there was little difference in the size distribution and abundance between nets for the 210–300?μm size classes. Thus, the 153-μm net could still be a useful tool for assessing density trends of larger veligers just prior to their settlement. Newly settled mussels (≤2?mm) were most abundant in summer or fall at the nearshore and offshore sites but were nearly absent at the transitional site despite the high density of veligers there. Factors other than veliger density must play an important role in mussel recruitment. 相似文献
6.
We consider the design of cost-sharing policies to motivate electricity distribution utilities to manage the costs of distributed energy resource (DER) projects. The optimal share of realized cost savings (s) that is awarded to the utility takes a relatively simple form in certain settings. More generally, s can vary with the prevailing environment in subtle and sometimes counterintuitive ways. For instance, s may increase as cost savings become less onerous for the utility to secure. Gains from affording the utility a choice among cost-sharing policies typically are minimal. 相似文献
7.
《Journal of the European Ceramic Society》2005,25(8):1355-1358
Growth kinetics and microstructural development of single crystal YBa2Cu3O7−x (Y123) superconductors, prepared by a melt texturing method under isothermal undercooling conditions, were investigated. At small undercooling, ΔT = 6 K, the initial growth of Y123 crystal was terminated at a size of ∼8 mm × 8 mm in the semisolid phase before the entire sample was fully solidified through the peritectic reaction. With incremental increase of ΔT, the growth of the crystal continued so that the whole sample (22 mm diameter and 8 mm thickness) solidified as a single crystal. Termination of the crystal growth at a given undercooling temperature was attributed to the coarsening process of Y211 particles in the melt associated with their surface energy contributions. Isothermal growth of large size Y123 single crystal requires a continuous supply of Y solute to the solidification interface which can be achieved by continuing dissolution of coarsening Y211 particles through further undercooling of the melt. 相似文献
8.
《Automation in Construction》2005,14(3):287-295
In the architecture, engineering and construction industries, computer visualization usage can cover the whole lifecycle of a product from presentation of initial concepts to the final stages of production and can also extend to maintenance issues. Three-dimensional walkthroughs can be created from hand drawn sketches at the very early stages of the design process. Three-dimensional models can be used by design teams to communicate design intent to client and users and to compare and evaluate design options. During more advanced stages of design, three-dimensional representations can be used to check the integrity of services coordination, accessibility and maintainability. During construction, visualization can facilitate the interpretation of design details by site operatives. The concept of visualization is not limited to modeling physical objects but can extend to the representation of abstract data sets of the type obtained from simulation programs used in performance assessment or from Computation Fluid Dynamics (CFD) applications. This paper will review the application of visualization in the process of design and construction and then present findings from three research projects that made use of some of these techniques at various stages of the process: for collaborative working during concept design stage, for design development and marketing in the house building sector, and for the modeling of design details during the construction stage. 相似文献
9.
《Information & Management》2021,58(8):103545
In this research, we report the information technologies rated as important by IT professionals in thirty-seven countries of the world, thus enhancing our understanding of the global technology landscape. Past research has focused primarily on the U.S. technology issues, which although useful in the U.S. context, may not generalize to all other countries. Globally, four core technologies have been ranked high for most of the countries: networks/telecommunications, business intelligence/analytics, enterprise application integration, and mobile and wireless applications. There were also differences among countries. Statistical analyses were performed to analyze the nature of these differences based on the economic level of the country and its IT infrastructure capability. Further insights were generated by performing cluster analysis; grouping the countries into three clusters (optimizers, pragmatists, and progressives), and examining their characteristics and technology priorities. These results are useful for multinational companies, governments, and international agencies as they forge their technology strategies and make investment decisions. We also lay the foundation for ongoing research to better understand the contextual factors that explain the differences in technology priorities among nations. 相似文献
10.
《Advanced Engineering Informatics》2012,26(4):889-903
With the capability of capturing detailed geometry of bridges in minutes, laser scanning technology has attracted the interests of bridge inspectors and researchers in the domain of bridge management. A challenge of effectively utilizing laser scanned point clouds for bridge inspection is that inspectors need to manually extract and measure large numbers of geometric features (e.g., points) for deriving geometric information items (e.g., the minimum underclearance) of bridges, named as bridge surveying goals in this research. Tedious manual data processing impedes inspectors from quantitatively understanding how various data processing options (e.g., algorithms, parameter values) influence the data processing time and the reliabilities of the surveying goal results. This paper shows the needs of automatic workflow executions for extracting surveying goals from laser scanned point clouds, and presents a computational framework for addressing these needs. This computational framework is composed of formal representations of workflows and mechanisms for constructing and executing workflows. Using a prototype system implemented based on this framework, we constructed and quantitatively characterized three workflows for extracting three representative bridge surveying goals, using three metrics of workflow performance defined in this research: exhaustiveness of measurement sampling, reliability of surveying goal results, and time efficiency. 相似文献