Day-Ahead Scheduling for Economic Dispatch of Combined Heat and Power with Uncertain Demand Response

This paper presents an energy management method for the interconnected operation of power, heat, Combined Heat and Power (CHP) units to settle the Day-Ahead market in the presence of a demand response program (DRP). A major challenge in this regard is the price uncertainty for DRP participants. First, the definitive model of the problem is introduced from the perspective of the Regional Market Manager (RMM) in order to minimize the total supply cost in the presence of TOU program, which is a type of DRP. Furthermore, a market-oriented tensile model is presented in the form of a combination of over-lapping generations (OLG) and price elasticity (PE) formulations to determine the amount of electricity demand in the TOU program. Then, a price uncertainty model of the proposed problem is introduced according to the IGDT risk aversion and risk-taking strategies considering information gap decision theory (IGDT). The above problem is solved through the use of the co-evolutionary particle swarm optimization (C-PSO) algorithm and the proposed model is implemented on a standard seven-unit system for a period of 24 hours.© 2022 authors. Published by IEEE. This work is licensed under a Creative Commons Attribution 4.0 License. For more information, see https://creativecommons.org/licenses/by/4.0/fi=vertaisarvioitu|en=peerReviewed

Effects of 2-chloroethylphosphonic acid (Ethrel) and selected environmental factors on growth of quackgrass (Agropyron repens L. (Beauv.)) and field bindweed (Convolvulus arvensis L.)

The primary purposes of these studies were to investigate: (1) the effects of air temperature, soil moisture, and supplemental light on sprouting ability of quackgrass (Agropyron repens L. (Beauv. )) rhizome buds; (2) the influence of 2-chloroethylphosphonic acid (Ethrel) on growth, morphology, and regenerative capacity of quackgrass and field bindweed (Convolvulus arvensis L.); and (3) the efficacy of Ethrel in enhancing the phytotoxicity of a mixture of 3-aminos- triazole and ammonium thiocyanate (amitrol-T) and 2, 2 -dichloro propionic acid (dalapon) on the regenerative capacity of quackgrass rhizomes. The studies were carried out in a greenhouse or growth chambers. The percent sprouting of the single-node quackgrass rhizome buds was decreased if the plants were subjected to 70°F day and 60°F night air temperatures, a reduced level of light intensity, or severe soil moisture stress. Ethrel applied to mature quackgrass plants effectively induced the rhizome buds to grow and develop into either rhizome branches or into leafless, rhizome-like aerial shoots. The aerial shoots did not develop normal leaves for two to four weeks. Later, as the effect of Ethrel diminished, normal leaves developed on the upper parts of the new shoots. Higher rates of Ethrel (4 to 6 lb/A) were more effective in evoking growth of the rhizome buds than the lower rates, but the resulting shoots remained leafless for a longer time. A high level of soil-applied nutrients also induced growth of quackgrass rhizome buds. In this regard, the effect of Ethrel and high soil nutrient level was simply additive not synergistic. Ethrel applied to intact quackgrass plants or to its excised rhizome buds did not increase or decrease the percent sprouting of the single-node rhizome buds. But the excised rhizome buds from quackgrass plants growing at a high level of soil nutrients had a higher percent sprouting. Over a six-week period, Ethrel (6 lb/A) application doubled the fresh and the dry weight of the leaves plus the newly formed shoots, moderately reduced the dry weight but not the fresh weight of the rhizomes, and inhibited root growth of the treated quackgrass plants in comparison to the untreated plants. Pre-treating quackgrass plants with Ethrel did not enhance the effectiveness of amitrol-T, applied subsequently, as measured by the average weight of regrowth produced by the replanted rhizome segments. But Ethrel in combination with amitrol-T completely inhibited the rhizome segments of 60% to 80% of the plants from producing any regrowth. When amitrol-T alone was used, the rhizome segments of 30% to 50% of the plants failed to have any regrowth. The rhizome pieces from quackgrass plants treated with Ethrel and dalapon produced more regrowth dry weight than the rhizome segments obtained from similar plants treated with dalapon alone. The reason for this antagonistic relation between Ethrel and dalapon was not investigated. Mature field bindweed plants sprayed with Ethrel sustained severe to complete defoliation. Many of the existing stems also died. The rootstocks of these plants, especially those treated with 1.0 lb Ethrel/A, were stimulated to initiate numerous visible shoot-buds. The initiated buds close to the soil surface emerged and developed into aerial shoots with minute leaves and short internodes. The rootstocks of field bindweed plants were segmented and replanted to measure their regrowth potential. The segmented rootstocks from Ethrel (1.0 lb/A) treated plants produced three times as many shoots and five times as much regrowth dry weight than the untreated plants. The effects of low rates of Ethrel (1/4 to 1.0 lb/A) on shoot and root growth of young field bindweed were similar to those of mechanical defoliation or mowing

Architecture of Electrical-energy Grids, Why and How?

Due to the complexity and large size on the one hand and addition of new equipment and technologies on the other hand, power systems may be subject to uneven or uncoordinated development. That is, development and addition of new technologies are mostly done locally, and then their effect on the whole system is observed in future. Such an approach endangers the long-term integrity and security of the power system. From economical point of view, it can also lead to waste of investment and poor asset management. Grid architecture is a topic that has been of interest in recent years to address these problems. Output of the grid architecture usually includes models and roadmaps that are aligned with the goals and requirements of the power system and coordinate downstream activities with upstream ones in the system. This paper presents the concepts, steps, notes and challenges of the grid architecture. A general view of the topic is presented that could be useful for researchers and those who are involved in the electricity industry

Ranking Sustainable Projects through an Innovative Hybrid DEMATEL-VIKOR Decision-Making Approach Using Z-Number

According to the heavy reliance of economic growth on environmental and social matters, sustainable development has turned into one of the main strategies of the organizations associated with selecting the project basket. Moreover, market conditions, rapid global changes in several aspects, uncertainty in intellectual judgments of the experts, and many other factors have increased uncertainty in problems of this kind. Accordingly, the main objective of this paper is to develop a mixed decision-making approach (DEMATEL-VIKOR) with the aim of ranking and evaluating suggested projects considering sustainability indices in a “mass production and infrastructural” company under uncertainty, while also taking reliability (Z-number information) into account. Given the existing uncertainty in the opinions of experts and previous data, fuzzy approach and Z-number information have been employed for weighting the filtered sustainability indices that are aligned with the objectives of the considered company (Z-DEMATEL), as well as ranking candidate projects (Z-VIKOR), which contribute to the main innovation of the present research. In addition, for scoring in the Z-number state, a novel definition of linguistic variable (fuzzy linguistic variable considering probabilities) has been put forward. The suggested approach was solved by an expert in two numerical examples in three certain, fuzzy, and Z-number scenarios, the results of which show that different results are obtained for different scenarios. Apart from that, given that Z-number takes the probability of reliance on the opinions of experts into consideration, the more the approach moves from being certain towards the fuzzy state and the Z-number state, the more the results approach the real world, hence yielding more reliable results. Therefore, results obtained from the proposed Z-DEMATEL-VIKOR approach are far more reliable. Moreover, significance weights in the Z-number scenario are 39%, 26%, and 36% in the economic, social, and environmental dimensions, respectively, which is indicative of the importance of social and environmental aspects apart from the economic dimension

Profit efficiency and ownership of German hospitals

This paper investigates the cost and profit efficiency of German hospitals and their variation with ownership type. It is motivated by the empirical finding that private (for-profit) hospitals – having been shown to be less cost efficient in the past – on average earn higher profits than public hospitals. We conduct a Stochastic Frontier Analysis on a multifaceted administrative German data set combined with the balance sheets of 541 hospitals of the years 2002–2006. The results show no significant differences in cost efficiency but higher profit efficiency of private than of publicly owned hospitals. Copyright (C) 2010 John Wiley & Sons, Ltd.hospital efficiency , ownership , stochastic frontier analysis , profit function ,

An Empirical Analysis of Bank Mergers and Cost Efficiency in Taiwan

This study compiled input and output panel data of 46 commercial banks in Taiwan during the period from 1997 to 1999 and used the two-stage method to evaluate the effects of bank mergers on bank efficiency. Generally speaking, a bank’s cost efficiency would be improved if the bank mergers happened between banks with different culture backgrounds. On the other hand, if the mergers happened between homogeneous banks, there would be little financial innovation and the cost efficiency would be unsubstantially improved. Another finding is that small banks have superior performance than larger banks in Taiwan. Also, efficiency would seem to dictate against merger mania. Copyright Springer 2005