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This paper presents part of the work ComEd and Quanta Technology have performed to quantify the locational and temporal value of DER to avoid distribution grid upgrade investments. It focuses on the formulation of a robust and efficient algorithm for DER optimal dispatch on a distribution feeder to mitigate the violation of current and voltage limits using the allocated cost of capacity and locational marginal value of real and reactive DER injection/withdrawal.  相似文献   
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Romanian policy makers have to perceive that human intervention on river basins land cover is influencing rainfall-runoff relation and the used methodology cannot accurately estimate watershed surface flow transformations. Global water cycles and energy fluxes understanding is leading to better predictions of land atmosphere interaction and local hydro-climates evolution. The water transfer time determination from rainfall to runoff needs accurate measurements of river basins hydrological parameters. Here, we analyzed and compared the lag time value results of two different methodologies (curve number and rational methodology) used for 54 Romanian small catchment areas study. The focus of this paper is the lag time evaluation and interpretation for an effective implementation of the best methodology approach in the Romanian geographical space. Our research in small river basins was developed using remote sensing technology maps, GIS and environmental datasets in combination with field work on every drainage basin in order to assess the specific morphological features and validate the land cover typology. We found that Soil Conservation Service - Curve Number (SCS-CN) method is widely used according to USA landscape features classification, but not necessarily applicable to Romanian river basins characteristics. Our results show how the official Romanian rational methodology national standard (RNS) can be improved and the limits of SCS-CN method.

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Clean Technologies and Environmental Policy - Food production and consumption is one of the major causes of global environmental degradation. One way to address environmental impacts in the food...  相似文献   
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The proliferating need for sustainability intervention in food grain transportation planning is anchoring the attention of researchers in the interests of stakeholders and environment at large. Uncertainty associated with food grain supply further intensifies the problem steering the need for designing robust, cost-efficient and sustainable models. In line with this, this paper aims to develop a robust and sustainable intermodal transportation model to facilitate single type of food grain commodity shipments while considering procurement uncertainty, greenhouse gas emissions, and intentional hub disruption. The problem is designed as a mixed integer non-linear robust optimisation model on a hub and spoke network for evaluating near optimal shipment quantity, route selection and hub location decisions. The robust optimisation approach considers minimisation of total relative regret associated with total cost subject to several real-time constraints. A version of Particle Swarm Optimisation with Differential Evolution is proposed to tackle the resulting NP-hard problem. The model is tested with two other state-of the art meta-heuristics for small, medium, and large datasets subject to different procurement scenarios inspired from real time food grain operations in Indian context. Finally, the solution is evaluated with respect to total cost, model and solution robustness for all instances.  相似文献   
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Stability constants and formation enthalpies of supramolecular complexes of crown ethers and their cyclic and acyclic analogues are determined on the basis of experimental data obtained by different physicochemical methods in the terms of a general approach developed and implemented in the ChemEqui software package. The established regularities of variation of stability of complexes are discussed as dependent on the ligand structure, nature of the cation, solvent, and anion. The applicability of the suggested method of determining complexation selectivity is shown for multicomponent equilibria in solutions.

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