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作者： Vyčítal, Václav Brno University of Technology

Finding cost efficient earthing system design with acceptable level of safety might be quite tedious work. Thus, many earthing system engineers try to find the most suitable design either by employing only their best experience or taking advantage of some more complex optimisation programs. Although both approaches might work well under certain circumstances, they might fail either due to counter-intuitiveness of the specific situation or by misunderstanding of the applied optimisation method, its limitations etc. Thus, in this paper, the earthing system design optimisation problem was addressed by analysing optimisation simulation results together with conducted sensitivity analysis. In the paper, a simple double ring earthing system was optimised while using five different optimisation methods. The earthing system was placed in different horizontally stratified soil models and the earthing system was optimised by minimising touch voltages instead of commonly minimised earth potential rise. The earthing system was modelled by Ansys Maxwell software. Apart from using Ansys Maxwell built-in optimisers, the possible solution space has also been mapped by performing sensitivity analysis with changing the earthing system design dimensions and the results of optimisation were compared and validated. It was found out that the Sequential non-linear programming Optimisation technique was quite superior to the other techniques. Additionally, in most cases, the Ansys Maxwell optimiser was able to found optimal solution; however, in some cases, based on the initial conditions, it might get stuck in local minima or the results might be influenced by the solution noise. Additionally, some quite non intuitive dependencies of earthing system electrodes positions had been found when different spatial dimensions constraints are used.

关键词： earthing earthing system optimisation Ansys Maxwell sensitivity analysis touch voltage non-linear programming

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Optimizing sustainable, affordable and healthy diets and estimating the impact of plant-based substitutes to milk and meat: A case study in Spain

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JOURNAL OF CLEANER PRODUCTION 2023年 424卷

作者： Munoz-Martinez, Julia Elias, Ricardo Abejon Batlle-Bayer, Laura Cusso-Parcerisas, Irene Carrillo-Alvarez, Elena Ramon Llull Univ Pedag Soc & Innovat Support Informat & Commun Technol PSITIC Res Grp FPCEE Blanquerna Barcelona Spain Ramon Llull Univ Global Res Wellbeing GRoW Res Grp FCS Blanquerna Barcelona Spain Univ Santiago Dept Chem Engn Santiago Chile Pompeu Fabra Univ UNESCO Chair Life Cycle & Climate Change ESCI UPF Barcelona Spain

The global food system is failing to appropriately nourish the population and has been identified as a driving force for environmental degradation. Changing current diets to healthier and more sustainable ones is key to decrease the incidence of non-communicable diseases and force changes at the production stage that will release environmental pressure. The determination of such diets is a challenge since it should be context specific, culturally acceptable, affordable, nutritionally adequate, and environmentally friendly. Through multiobjective optimization we aimed to determine a sustainable and healthy diet(SHD) in Spain with the minimum cost and environmental impact (assessed through GHGe, land use and blue-water use) that deviate the least from current consumption. Additionally, this research also compares the optimised diet with the Spanish food-based dietary guidelines(FBDG), and explores the potential benefits of reducing animal meat and milk while replacing them with plant-based alternatives. Compared to current consumption, a SHD in Spain can be more nutritious and reduce cost, GHGe, land and blue-water use by 32%, 46%, 27%, and 41%, respectively. The Spanish intake displayed the worst nutritional assessment and the highest values for GHGe and land use. The Spanish FBDG showed the highest cost and blue-water usage. Further analysis revealed that plant-based meat alternatives are not necessary to achieve a nutritionally adequate diet at the minimum cost and environmental impact. Shifting to fortified plant-based milk alternatives may add additional environmental benefits. This work emphasizes the potentiality of using optimization to determine a SHD and identifies important gaps to be fulfilled in future research.

关键词： Life cycle assessment Sustainable diet non-linear programming Affordability Spain Nutritional adequacy (max 6)

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Adaptive neural network model based predictive control of an internal combustion engine with a new optimization algorithm

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PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART D-JOURNAL OF AUTOMOBILE ENGINEERING 2006年第D2期220卷 195-208页

作者： Wang, SW Yu, DL Gomm, IB Page, GF Douglas, SS Liverpool John Moores Univ Control Syst Res Grp Sch Engn Liverpool L3 3AF Merseyside England

This paper presents an application of adaptive neural network modelling and model-based predictive control (MPC) for an engine simulation. A radial basis function (RBF) neural network trained by a recursive least-squares (RLS) algorithm is compared with the network with fixed parameters and demonstrated to be more suitable for modelling the crankshaft speed, the intake manifold pressure, and the manifold temperature. Based on the obtained adaptive neural network model, an MPC strategy for controlling the crankshaft speed is realized successfully. A reduced Hessian method, a newly developed sequential quadratic programming (SQP) method for solving non-linear programming (NLP) problems, is implemented to solve the non-linear optimization in MPC. Some important modifications are proposed for the algorithm settings in this research to make the reduced Hessian method more appropriate for the adaptive neural network model based predictive control strategy of internal combustion (IC) engines.

关键词： engine control adaptive neural networks non-linear programming reduced Hessian method predictive control

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Optimal Placement of Phasor Measurement Units with linear and non-linear Models

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ELECTRIC POWER COMPONENTS AND SYSTEMS 2015年第4期43卷 357-373页

作者： Theodorakatos, Nikolaos P. Manousakis, Nikolaos M. Korres, George N. Natl Tech Univ Athens ECE Dept Athens Greece

Abstract-This article presents a non-linear programming-based model for the optimal placement of phasor measurement units. The optimal phasor measurement units placement is formulated to minimize the number of phasor measurement units required for full system observability and to maximize the measurement redundancy at all buses in a power system. A sequential quadratic programming algorithm is used for the solution of the proposed model. The existence of power flow and injection measurements, the limited phasor measurement units channel capacity, the lack of communication facilities in substations, and the single phasor measurement units loss are also incorporated into the initial proposed formulation. The non-linear programming model is applied to IEEE 14- and 118-bus test systems in MATLAB. The accuracy and the effectiveness of the proposed method is verified by comparing the simulation results to those obtained by a binary integer programming model also implemented in MATLAB. The comparative study shows that the proposed non-linear programming model yields the same number of phasor measurement units as the binary integer programming model. A remarkable advantage of the non-linear programming against binary integer linear programming is its capability to give more than one optimal solution, each one having the same minimum number of phasor measurement units (same minimum objective value), but at different locations.

关键词： binary integer linear programming optimization mixed integer linear programming Phasor measurement unit observability sequential quadratic programming optimal placement non-linear programming

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Operační výzkum v oblastech recyklace odpadů

Operační výzkum v oblastech recyklace odpadů

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作者： Camara, Assa Brno University of Technology

Bakalárska práca je zamerané na nájdenie a popísanie matematického modelu, ktorý rekonštruuje skutočné súčasné finančné náklady na zber a zvoz odpadu na ... 详细信息

Bakalárska práca je zamerané na nájdenie a popísanie matematického modelu, ktorý rekonštruuje skutočné súčasné finančné náklady na zber a zvoz odpadu na úrovní obcí s rozšírenou pôsobnosťou, ktoré nie sú ináč dostupné a sú potrebné na ďalšie plánovanie s využiteľným odpadom. Na vytvorenie modelu sú použité znalosti z optimalizácie, štatistiky a teórie grafov, ktoré sú v texte zhrnuté. Model je aplikovaný na skutočné dáta v prostredí GAMS. Výsledky aplikácie sú okomentované a analyzované. Na základe tejto analýzy sú uvedené aj možnosti vývoja tohto modelu.

关键词： štatistika nelineárne programovanie náklady na spracovanie odpadu komunálny odpad tok v sieti statistics non-linear programming waste treatment costs municipal waste network flow Text

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Tvorba optimálních sazeb v neživotním pojištění

Tvorba optimálních sazeb v neživotním pojištění

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作者： Ďurošková, Zuzana Charles University of Prague

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Klasické a moderní přístupy k sazbování v neživotním pojištění

Klasické a moderní přístupy k sazbování v neživotním...

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作者： Vojtěch, Jonáš Charles University of Prague

Title: Traditional and modern approaches to pricing in nonlife insurance Abstract: This thesis deals with the theory and implementation of generalized linear models in the area of pricing of non-life insurance and subsequent optimalization of rates. Using the generalized linear models it is possible to estimate expected value and variance of compound distribution of total claims made according to insurance policy during definite time period. The next step is to build an optimalization model and describe several methods how to determine rates that lead to optimal distribution of safety margins within insurance policies in particular risk groups. Represented approaches how to calculate insurance premiums are numerically illustrated on simulated data in concluding parts of the thesis.

关键词： non-life insurance pricing generalized linear model non-linear programming optimal allocation

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Hybridization of the imperialist competitive algorithm and local search with application to ship design optimization

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COMPUTERS & INDUSTRIAL ENGINEERING 2019年 137卷 106069-000页

作者： Peri, Daniele CNR Ist Applicaz Calcolo Via Taurini 19 I-00185 Rome Italy

In the wide scenario of the optimization techniques, a large number of algorithms are inspired by natural processes, in many different ways. One of the latest is the Imperialist Competitive Algorithm (ICA) Atashpaz-Gargari and Lucas (2007), judged by their authors as very efficient and competitive with other popular optimization algorithms. However, its diffusion is still limited, so that it has not yet been adequately studied. In this paper, we have investigated the convergence properties of the ICA algorithm, observing the effect of the various coefficients and their role in the global convergence. Some modifications, including the coupling with a local search method, have been listed/suggested and then tested on a suite of standard algebraic test functions, verifying the improvements on the speed of convergence of the original algorithm. An application to naval design has been also included, in order to check the ability to solve realistic problems.

关键词： Global optimization non-linear programming Evolutionary optimization Hybrid optimization methods Imperialist competitive algorithm Ship design optimization

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Synthesis of Heat-Integrated Water Allocation Networks: A Meta-Analysis of Solution Strategies and Network Features

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ENERGIES 2018年第5期11卷 1158-1158页

作者： Kermani, Maziar Kantor, Ivan D. Marechal, Francois Ecole Polytech Fed Lausanne EPFL Valais Wallis Ind Proc & Energy Syst Engn IPESE Grp Rue Ind 17Case Postale 440 CH-1951 Sion Switzerland

Industries consume large quantities of energy and water in their processes which are often considered to be peripheral to the process operation. Energy is used to heat or cool water for process use;additionally, water is frequently used in production support or utility networks as steam or cooling water. This enunciates the interconnectedness of water and energy and illustrates the necessity of their simultaneous treatment to improve energy and resource efficiency in industrial processes. Since the seminal work of Savulescu and Smith in 1998 introducing a graphical approach, many authors have contributed to this field by proposing graphically-or optimization-based methodologies. The latter encourages development of mathematical superstructures encompassing all possible interconnections. While a large body of research has focused on improving the superstructure development, solution strategies to tackle such optimization problems have also received significant attention. The goal of the current article is to study the proposed methodologies with special focus on mathematical approaches, their key features and solution strategies. Following the convention of Je. zowski, solution strategies are categorized into: decomposition, sequential, simultaneous, meta-heuristics and a more novel strategy of relaxation/transformation. A detailed, feature-based review of all the main contributions has also been provided in two tables. Several gaps have been highlighted as future research directions.

关键词： mathematical programming superstructure optimization solution strategy heat-integrated mass allocation network (HIMAN) non-linear programming heat integration non-isothermal mixing benchmarking sequential simultaneous

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Selected Mathematical Optimization Methods for Solving Problems of Engineering Practice

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ENERGIES 2022年第6期15卷 2205页

作者： Vagaska, Alena Gombar, Miroslav Straka, L'uboslav Tech Univ Kosice Fac Mfg Technol Seat Presov Dept Nat Sci & Humanities Presov 08001 Slovakia Univ Presov Fac Management & Business Dept Management Presov 08001 Slovakia Tech Univ Kosice Fac Mfg Technol Seat Presov Dept Automobile & Mfg Technol Presov 08001 Slovakia

Engineering optimization is the subject of interest for many scientific research teams on a global scale;it is a part of today's mathematical modelling and control of processes and systems. The attention in this article is focused on optimization modelling of technological processes of surface treatment. To date, a multitude of articles are devoted to the applications of mathematical optimization methods to control technological processes, but the situation is different for surface treatment processes, especially for anodizing. We perceive their lack more, so this state has stimulated our interest, and the article contributes to filling the gap in scientific research in this area. The article deals with the application of non-linear programming (NLP) methods to optimise the process of anodic oxidation of aluminium using MATLAB toolboxes. The implementation of optimization methods is illustrated by solving a specific problem from engineering practice. The novelty of this article lies in the selection of effective approaches to the statement of optimal process conditions for anodizing. To solve this complex problem, a solving strategy based on the design of experiments approach (for five factors), exploratory data analysis, confirmatory analysis, and optimization modelling is proposed. The original results have been obtained through the experiment (performed by using the DOE approach), statistical analysis, and optimization procedure. The main contribution of this study is the developed mathematical-statistical computational (MSC) model predicting the thickness of the resulting aluminium anodic oxide layer (AOL). Based on the MSC model, the main goal has been achieved-the statement of optimal values of factors acting during the anodizing process to achieve the thickness of the protective layer required by clients, namely, for 5, 7, 10, and 15 [mu m].

关键词： engineering optimization mathematical optimization methods constrained optimization non-linear programming MATLAB aluminum anodic oxidation

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