Residential variable energy price schemes can be made more effective with the use of a demand response (DR) strategy along with smart appliances. Using DR, the electricity bill of participating customers/households ca...
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Residential variable energy price schemes can be made more effective with the use of a demand response (DR) strategy along with smart appliances. Using DR, the electricity bill of participating customers/households can be minimised, while pursuing other aims such as demand-shifting and maximising consumption of locally generated renewable-electricity. In this article, a two-stage optimization method is used to implement a price-based implicit DR scheme. The model considers a range of novel smart devices/technologies/schemes, connected to smart-meters and a local DR-Controller. A case study with various decarbonisation scenarios is used to analyse the effects of deploying the proposed DR-scheme in households located in the west area of the Isle of Wight (Southern United Kingdom). There are approximately 15,000 households, of which 3000 are not connected to the gas-network. Using a distribution network model along with a load flow software-tool, the secondary voltages and apparent-power through transformers at the relevant substations are computed. The results show that in summer, participating households could export up to 6.4 MW of power, which is 10% of installed large-scale photovoltaics (PV) capacity on the island. Average carbon dioxide equivalent (CO(2)e) reductions of 7.1 ktons/annum and a reduction in combined energy/transport fuel-bills of 60%/annum could be achieved by participating households.
We consider an EOQ inventory model for growing items, wherein the value and size of items increase during time, some instances of these items are livestock, fish, and poultry. The main difference between this inventor...
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We consider an EOQ inventory model for growing items, wherein the value and size of items increase during time, some instances of these items are livestock, fish, and poultry. The main difference between this inventory system and older ones is weight increment of products during stocking without buying more. This paper studies an inventory system of poultries that new-born items are fed to reach the ideal weight for consumers. In this study, based on the consumers' preference of fresh foods over frozen items, we assume that shortage is permitted and consumers wait for fresh items when company pays some additional penalties, i.e., the shortage is fully backordered. On the other hand, for each cycle, the producer must prepare the place in terms of hygiene conditions;thus, a setup time per cycle is considered. The aim of this study is to obtain optimum system solution, such that total costs, including setup, purchasing, holding, feeding, and shortage, are minimized. To do so, we employ mathematical measures to approximate growing rates and model the system as a non-linear programming. To solve the obtained optimization model, we employ hessian matrix to obtain optimal solution for this inventory system. The proposed EOQ inventory model helps poultry industries in Iran to optimize their system considering costs and permissible shortage, and it can be employed in other countries. Finally, we provide a numerical example and its sensitivity analysis, plus some potential future directions.
Harmonic generation is an attractive research field that finds a variety of application areas. However, harmonic generation within a medium of micron-scale interaction length limits the magnitude of nonlinear coupling...
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Harmonic generation is an attractive research field that finds a variety of application areas. However, harmonic generation within a medium of micron-scale interaction length limits the magnitude of nonlinear coupling and leads to poor harmonic generation efficiency. In this study, we present a constrained non-linear programming approach based on the Quasi-Newton Broyden-Fletcher-Goldfarb-Shanno (BFGS) algorithm to obtain high-fidelity harmonic generation in optical micro-resonators. Using this approach, one can achieve high-intensity harmonic generation in a simple Fabry-Perot type optical micro-resonator. The generation of super-intense harmonics at a typical ultraviolet (UV)-ablation frequency of 820 THz and at pure yellow-light (515 THz) is investigated in particular. Moreover, we achieved more than 98% accuracy compared to well-known theoretical results. Our approach enables the design of highly efficient microscale harmonic generators to be used in integrated photonic devices.
The experience of designing a track with the use of the basic elements method showed its high effectiveness with the possibilities for the further improvement of the process of the automatized designing for the purpos...
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ISBN:
(纸本)9783319908359;9783319908342
The experience of designing a track with the use of the basic elements method showed its high effectiveness with the possibilities for the further improvement of the process of the automatized designing for the purpose of full elimination of the stage of graphical elaboration of the track and automatic consideration of all requirements set to it. For the purpose of realization of these possibilities, the issues of designing a clothoid track by approximation of succession of points of a sketch line with application of the methods of non-linear programming were viewed (method of approximation of succession of points). This method sets the task of the best approximation of the track to the set succession of point of the sketch line.
We propose a new family of relaxation schemes for mathematical programs with vanishing constraints that extend the relaxation of Hoheisel, Kanzow & Schwartz from 2012. We discuss the properties of the sequence of ...
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We propose a new family of relaxation schemes for mathematical programs with vanishing constraints that extend the relaxation of Hoheisel, Kanzow & Schwartz from 2012. We discuss the properties of the sequence of relaxed non-linear programs as well as stationary properties of limiting points. Our relaxation schemes have the desired property of converging to an M-stationary point. A main advantage of this new method is to converge to an S-stationary point satisfying MPVC-LICQ for a large class of problem. We also study MPVC constraint qualification connected to this study and prove convergence of the method under the new MPVC-CRSC. Additionally, we obtain the new MPVC-wGCQ and prove that it is the weakest MPVC constraint qualification.
In order to improve the performance of time difference of arrival(TDOA)localization,a nonlinear least squares algorithm is proposed in this ***,based on the criterion of the minimized sum of square error of time diffe...
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In order to improve the performance of time difference of arrival(TDOA)localization,a nonlinear least squares algorithm is proposed in this ***,based on the criterion of the minimized sum of square error of time difference of arrival,the location estimation is expressed as an optimal problem of a non-linear ***,an initial point is obtained using the semi-definite *** finally,the location is extracted from the local optimal solution acquired by Newton *** results show that when the number of anchor nodes is large,the performance of the proposed algorithm will be significantly better than that of semi-definite programming approach with the increase of measurement noise.
This study mainly focuses on the design of a new cantilever structure and its minimal mass optimization subject to yield and buckling constraints. Given a vertical force in a constant distance from a vertical wall, th...
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This study mainly focuses on the design of a new cantilever structure and its minimal mass optimization subject to yield and buckling constraints. Given a vertical force in a constant distance from a vertical wall, the minimal mass design of a two elements structure with and without anchorage length limitation of the wall is first studied. To further reduce the total structural mass of, a sector cantilever structure is proposed, and the advantage of choosing equal bar length and connecting strings to the center of a circle is proved. Given finite anchorage length of the wall, a tailored sector cantilever structure with finite anchorage length is proposed. Minimal mass design of the sector cantilever with and without anchorage length constraint can be obtained by processing a constrained nonlinear optimization of shape parameters. Considering the penalty of joint mass, the optimal complexity of the sector cantilever will decrease as the penalty coefficient increases. Numerical results are given to show the efficiency of the proposed cantilever structures in saving mass.
This paper presents a methodology to optimize the parameters of the frequency controller installed in a battery energy storage system (BESS) to minimize frequency deviation considering electricity system operator (ESO...
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ISBN:
(纸本)9781538647226
This paper presents a methodology to optimize the parameters of the frequency controller installed in a battery energy storage system (BESS) to minimize frequency deviation considering electricity system operator (ESO) imposed rate of change constraints. The problem is formulated with a non-linear programming (NLP) structure and the exterior penalty function (EPF) method is applied to solve it efficiently. The impact of the location of the BESS on the frequency nadir is quantified by simulations in a medium voltage (MV) distribution network benchmark with a high proportion of distributed energy resources (DER). Simulations are performed with detailed dynamic models in DIgSILENT (R) Power Factory (TM) in combination with Python for data analysis and manipulation. Simulation results show the suitability of the proposed approach.
As today's distribution grid is experiencing increased rooftop solar installations, there is growing interest in evaluating the PV hosting capacity (HC) of the grid. Since, predicting the exact size and location o...
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ISBN:
(纸本)9781728104942
As today's distribution grid is experiencing increased rooftop solar installations, there is growing interest in evaluating the PV hosting capacity (HC) of the grid. Since, predicting the exact size and location of potential PV installations is not feasible at the distribution grid planning phase, a stochastic method is employed to choose a finite number of combinations of possible PV size and location. As a result, the calculated PV HC is a range of total PV capacity in MW that a circuit can accommodate and not a single value. Additionally, the calculated PV HC range is not unique;it varies with the PV distribution considered for the analysis. This paper proposes an optimal power flow based formulation to find the maximum PV capacity in MW that can be accommodated in a given distribution grid. The PV HC values are evaluated for IEEE 123 bus circuit by the proposed method and the results are compared with the conventional approach. It is observed that the results of the optimal power flow method is unique and can act as the upper bound for the stochastic PV HC analysis.
We study multi-level optimization problem on energy system, transportation system and informa- tion network. We use the concept of boundedly rational user equilibrium (BRUE) to predict the behaviour of users in system...
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We study multi-level optimization problem on energy system, transportation system and informa- tion network. We use the concept of boundedly rational user equilibrium (BRUE) to predict the behaviour of users in systems. By using multi-level optimization method with BRUE, we can help to operate the system work in a more efficient way. Based on the introducing of model with BRUE constraints, it will lead to the uncertainty to the optimization model. We generate the robust optimization as the multi-level optimization model to consider for the pessimistic condition with uncertainty. This dissertation mainly includes four projects. Three of them use the pricing strat- egy as the first level optimization decision variable. In general, our models' first level's decision variables are the measures that we can control, but the second level's decision variables are users behaviours that can only be restricted within BRUE with uncertainty.
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