We study the stability of an equilibrium of arbitrarily switched, autonomous, continuous-time systems through the computation of a common Lyapunov function (CLF). The switching occurs between a finite number of indivi...
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We study the stability of an equilibrium of arbitrarily switched, autonomous, continuous-time systems through the computation of a common Lyapunov function (CLF). The switching occurs between a finite number of individual subsystems, each of which is assumed to be linear. We present a linear programming (LP) based approach to compute a continuous and piecewise affine (CPA) CLF and compare this approach with different methods in the literature. In particular we compare it with the prevalent use of linear matrix inequalities (LMIs) and semidefinite optimization to parameterize a quadratic common Lyapunov function (QCLF) for the linear subsystems.
Zn deficiency arising from inadequate dietary intake of bioavailable Zn is common in children in developing countries. Because house crickets are a rich source of Zn, their consumption could be an effective public hea...
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Zn deficiency arising from inadequate dietary intake of bioavailable Zn is common in children in developing countries. Because house crickets are a rich source of Zn, their consumption could be an effective public health measure to combat Zn deficiency. This study used Optifood, a tool based on linear programming analysis, to develop food-based dietary recommendations (FBR) and predict whether dietary house crickets can improve both Zn and overall nutrient adequacy of children's diets. Two quantitative, multi-pass 24-h recalls from forty-seven children aged 2 and 3 years residing in rural Kenya were collected and used to derive model parameters, including a list of commonly consumed foods, median serving sizes and frequency of consumption. Two scenarios were modelled: (i) FBR based on local available foods and (ii) FBR based on local available foods with house crickets. Results revealed that Zn would cease to be a problem nutrient when including house crickets to children's diets (population reference intake coverage for Zn increased from 89 % to 121 % in the best-case scenario). FBR based on both scenarios could ensure nutrient adequacy for all nutrients except for fat, but energy percentage (E%) for fat was higher when house crickets were included in the diet (23 E% v. 19 E%). This manoeuvre, combined with realistic changes in dietary practices, could therefore improve dietary Zn content and ensure adequacy for twelve nutrients for Kenyan children. Further research is needed to render these theoretical recommendations, practical.
linear programming is a technique widely used in decision-making nowadays. linear programming in a fuzzy environment makes it even more interesting due to the vagueness and uncertainty of the available resources and v...
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linear programming is a technique widely used in decision-making nowadays. linear programming in a fuzzy environment makes it even more interesting due to the vagueness and uncertainty of the available resources and variables. Since the market price and profit of certain goods are not known exactly, considering fuzzy variables and parameters in the linear programming makes it more closer to the real-life situation;therefore, it becomes more attractive for the decision-makers. In a fuzzy environment, there is only one information and that is the possibility of the variable. In many real-world problems, we need the reliability of the information along with its possibility. Zadeh suggested a Z-number Z = (A;B) with two components, A carrying the information of possibility of the variable, and B carrying the information about reliability of the first component A. linear programming with its parameters and variables carrying the information in the form of Z number is even more exciting for the decision-makers. Because every decision-maker demands information that is more reliable, linear programming in a Z-number environment with both its components taken as fuzzy numbers is a very attractive problem. In this paper, we present linear programming problems with the parameters and variables taken as Z number having triangular fuzzy numbers as possibility and reliability. We also suggest an interactive method to solve Z number linear programming problems by converting Z-numbers into conventional fuzzy numbers and then using the ranking of fuzzy numbers. We also present applications of the proposed models by solving numerical examples. We also test the authenticity of the proposed method by comparing the results with the existing techniques.
The government of Paraguay designed a National Development Plan 2030 with strategies and goals to achieve poverty reduction, social development, and inclusive economic growth. Despite the efforts above, family farmers...
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ISBN:
(纸本)9783031782404;9783031782411
The government of Paraguay designed a National Development Plan 2030 with strategies and goals to achieve poverty reduction, social development, and inclusive economic growth. Despite the efforts above, family farmers are affected by food insecurity and are losing dominance partly due to their operations' lack of sustainability and profitability. Furthermore, excessive self-consumption of their crops leads to inadequate diets with low-cost, high-energy, and nutrient-poor foods. In the case study analyzed for the Department of Caazapa of Paraguay, the farms served by the ALATs allocate 90% of their land to traditional crops: sesame, cassava, corn, and beans. In addition, they self-consume around 65% of their production. Therefore, they produce to subsist. In this work, we propose a deterministic mixed integer linear model considering the primary agricultural operations and the requirements to produce multiple crops in multiple periods, emphasizing demand satisfaction and cooperation among small farmers. The O seeks tomaximize the farmer's profit and the food security of the farm, considering, on the one hand, the operating costs and, on the other hand, income from product sales, self-consumption of crops, and the exchange of products between farmers. To include the dimensions of sustainability, this research addresses, among other aspects, the increase in the levels of profitability and food security (FS) of farmers in a developing country, proposing to carry out their operations from the perspective of an Agricultural Supply Chain (ASC) and generating, in the case study, alternative production planning to the plans suggested by the Local Technical Assistance Agencies (ALATs).
With the arrival of the 5G era, centralized cloud computing is gradually shifting to edge computing. However, due to the characteristics of distributed multi-deployment of edge computing, it is difficult to ensure tha...
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With the arrival of the 5G era, centralized cloud computing is gradually shifting to edge computing. However, due to the characteristics of distributed multi-deployment of edge computing, it is difficult to ensure that all edge-node clusters have enough resources. Faced with the limited resources of edge-node cluster, how to carry out reasonable resource scheduling and provide users with high-quality services (high quality and low delay) has become the focus of current research. Aiming at this problem, in this paper, the edge-node resource scheduling based on linear programming is the key technology being studied. It is compared with conventional algorithm-based edge-node resource scheduling system. In the five deployments of the edge node resource scheduling system under the conventional algorithm, 8 virtual machines are used. The edge node resource scheduling system under the linear programming algorithm uses 7 virtual machines for 3 deployments and 8 virtual machines for 2 deployments. It can be seen that the results affirm the feasibility of edge node resource scheduling based on linear programming, and make due contributions to current research.
Among the many technologies for increasing the efficiency of oil field development using waterflooding, the least economically expensive include hydrodynamic methods for increasing oil recovery, based on changing the ...
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Among the many technologies for increasing the efficiency of oil field development using waterflooding, the least economically expensive include hydrodynamic methods for increasing oil recovery, based on changing the directions of filtration flows. Thus, one of the key tasks of increasing the efficiency of waterflooding at a late stage of development is to reduce the volume of ineffective injection. The article discusses the problem of redistributing volumes of injected water between injection wells for a given total injection volume in order to increase oil production. An analytical relationship is proposed for assessing injection efficiency, based on known displacement characteristics and calculated well interference coefficients based on CRMP. The optimization problem is formulated as a linear programming problem. Using the example of a fragment of an oil deposit, the possibility of assessing the injectivity of injection wells is shown, which makes it possible to increase the predicted oil production by changing the direction of filtration flows in the formation. As a result of applying the developed algorithm, the predicted increase in cumulative oil production amounted to 19683 m(3) (9.5%) over 15 years.
Intuitionistic fuzzy set (InFS) theory represents a paradigm change in handling strategic planning challenges, one of the most important issues in the physical realm. Aggregation operators (AOs) have a big part to pla...
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Egypt has started constructing its New Administrative Capital since 2015. The new capital was designed to meet smart city standards, which presents a challenge for businesses to make the optimum business decisions giv...
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Egypt has started constructing its New Administrative Capital since 2015. The new capital was designed to meet smart city standards, which presents a challenge for businesses to make the optimum business decisions given the set budget for such a project. As a result, reaching the optimum solution for allocating the needed materials to each building became important. Many researchers have considered the theory of constraints in their studies to determine the optimum product mix. Frequently, research considers the target of profit maximization to reach the optimum solution with one scenario. In this paper, we aim to solve the problem of product mix in cement production, which organizations face. The problem was formulated based on a case study in Egypt with two linear programming approaches. For this problem, many scenarios were presented under the consideration of two aspects, which are resource utilization and productivity. Data visualization was used in this paper to simplify the procedure of decision-making. Also, a dashboard web application was made for the decision makers to make it easier to create, analyze, and see different business scenarios.
Current drive control systems tend to push control loops to the limits of their performance. One of the ways of doing so is to use advanced optimization algorithms, usually related to model-based off-line calculations...
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Current drive control systems tend to push control loops to the limits of their performance. One of the ways of doing so is to use advanced optimization algorithms, usually related to model-based off-line calculations, such as genetic algorithms, the particle swarmoptimisation or the others. There is, however, a simpler way, namely to use predictive control formalism and by formulation of a simple linear programming problem which is easy to solve using powerful solvers, without excessive computational burden, what is a reliable solution, as whenever the optimization problem has a feasible solution, a global minimizer can be efficiently found. This approach has been deployed for a servo drive system operated by a real-time sampled-data controller, verified between model-in-the-loop and hardware-in-the-loop configurations, for a range of prediction horizons, as an attractive alternative to classical quadratic programming-related formulation of predictive control task.
In this paper we present a simple technique to derive certificates of non-realizability for a combinatorial polytope. Our approach uses a variant of the classical algebraic certificates introduced by Bokowski and Stur...
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In this paper we present a simple technique to derive certificates of non-realizability for a combinatorial polytope. Our approach uses a variant of the classical algebraic certificates introduced by Bokowski and Sturmfels (1989), the final polynomials. More specifically we reduce the problem of finding a realization to that of finding a positive point in a variety and try to find a polynomial with positive coefficients in the generating ideal (a positive polynomial), showing that such point does not exist. Many, if not most, of the techniques for proving non-realizability developed in the last three decades can be seen as following this framework, using more or less elaborate ways of constructing such positive polynomials. Our proposal is more straightforward as we simply use linear programming to exhaustively search for such positive polynomials in the ideal restricted to some linear subspace. Somewhat surprisingly, this elementary strategy yields results that are competitive with more elaborate alternatives, and allows us to derive new examples of non-realizable combinatorial polytopes. (C) 2022 Elsevier Ltd. All rights reserved.
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