Fighting energy poverty in a typical Peruvian rural house

This study evaluates a typical, informal construction in the Peruvian highlands of Cuzco, a site at an Equatorial latitude (13,5° S), approximately, 3.400 mamsl, with a subtropical highland climate (Köppen Cwb). Its aim is to compare low-cost passive retrofit strategies, applicable in cities and rural areas with similar climate, and validate a best choice. To carry out this study a dynamic energy simulation was performed, using the typical meteorological year (IWEC) provided by ASHRAE. The model was used to understand the effects of simple changes in the envelope configuration and the associated effect on infiltration, and their combination, on the indoor comfort and the energy performance of the building. The outcomes were displayed in a simple Energy-needs/transformation cost chart and a Pareto curve was selected, identifying an optimal subset of solutions. Adequate indoor conditions can be obtained with the implementation of only passive strategies, mainly empowering the thermal insulation of walls, roofs and windows using simple, low cost, local technologies, and the control of the heat transmission toward the soil: the energy poverty of the informal settlements of Cuzco can be fought with very simple initiatives, that require investments with a reasonably short return of investment.

Pareto Effect of LMI for Ship Propulsion

The aim of this study was to analyze the dynamics of a multidimensional object based on the Pareto curve for the Linear Matrix Inequalities (LMI) controller. The study was carried out based on an available “Blue Lady” training vessel model controller with the use of a MATLAB and Simulink simulation package. Research was focused on optimising both the energy to be used when manoeuvring and the ship’s dynamics. Analysis was combined with the application of H2/H∞ norms finding the Pareto optimal solution for mixed norms used at the γ∞ parameter. Observations for a multidimensional ship model proved that it is possible to optimize the system, using principles of the Pareto curve, to reduce energy consumption in steering-propulsion systems while performing precise manoeuvres in ports correctly. Parameter values, received from observations of operation of individual steering-propulsion systems, proved to be reasonable.

Comparison of Soviet and post-Soviet Russian settlement systems with the US settlement system, 1959-2020

The lack of discernible changes in the Russian (hereinafter RF) settlement system after the transition from a centrally managed economy to a capitalist economy seems to be contrary to the established view of the exceptional character of capitalist-style settlement systems. To explain this misunderstanding, we compared the state of settlement systems in Russia and in the United States between 1959 and 2020 in this paper. The measures of shape of the Pareto curve were used to quantify the state of the settlement systems: critical exponent, asymmetry coefficient, and Gini coefficient. The study found that the system of settlement in RF territories during the Soviet and post-Soviet periods had the same order and development trend as the system of settlement in US states. The order of urban systems in regions correlates with the local average annual temperatures. The results have led us to conclude that the settlement systems were independent from the economic paradigm.

Time-Varying Semidefinite Programs

We study time-varying semidefinite programs (TV-SDPs), which are semidefinite programs whose data (and solutions) are functions of time. Our focus is on the setting where the data vary polynomially with time. We show that under a strict feasibility assumption, restricting the solutions to also be polynomial functions of time does not change the optimal value of the TV-SDP. Moreover, by using a Positivstellensatz (positive locus theorem) on univariate polynomial matrices, we show that the best polynomial solution of a given degree to a TV-SDP can be found by solving a semidefinite program of tractable size. We also provide a sequence of dual problems that can be cast as SDPs and that give upper bounds on the optimal value of a TV-SDP (in maximization form). We prove that under a boundedness assumption, this sequence of upper bounds converges to the optimal value of the TV-SDP. Under the same assumption, we also show that the optimal value of the TV-SDP is attained. We demonstrate the efficacy of our algorithms on a maximum-flow problem with time-varying edge capacities, a wireless coverage problem with time-varying coverage requirements, and on biobjective semidefinite optimization where the goal is to approximate the Pareto curve in one shot.

Aspects of Pareto distributions

Different skew models, such as the lognormal and the Pareto functions, have been proposed as suitable descriptions of income distribution. Specific distributions are usually applied in empirical investigations. It is a common opinion that the Pareto curve often provides an adequate description of higher incomes. Recently, double Pareto distributions that obey the power law in both the upper and lower tails have been suggested to reflect a general distribution of personal income. In this study, the literature concerning double Pareto models is presented and the model is applied to Finnish income data. JEL classification numbers: I32. Keywords: Maximum likelihood estimate, Method of moments, Bayesian method, Mean Squared Error, Lognormal, double Pareto, Coefficient of determination, survival function, Geometric Brownian motion.

An oppositional Salp Swarm: Jaya algorithm for thermal design optimization of an Organic Rankine Cycle

This study proposes a hybrid metaheuristic algorithm to tackle both single and multi objective optimization problems that are subjected to hard constraints. Twenty-four single objective optimization benchmark problems comprising unimodal and multi modal test functions have been solved by the proposed hybrid algorithm (OPSSAJ) and numerical results have been compared with those acquired by some of the new emerged metaheuristic optimizers. The proposed OPSSAJ shows a significant accuracy and robustness in most of the cases and proves its efficiency in solving high dimensional problems. As a real-world case study, seventeen operational design parameters of an organic rankine cycle (ORC) operating with a binary mixture of R227EA and R600 refrigerants are optimized by the proposed hybrid OPSSAJ to obtain the optimum values of contradicting dual objectives of second law efficiency and Specific Investment Cost. A Pareto curve composed of non-dominated solutions is constructed through the weighted sum method and the final solution is chosen by the reputed TOPSIS decision-maker. The pareto curve and best-compromising result obtained by utilizing the OPPSAJ are compared with that of acquired by using nondominated sorting genetic algorithm II (NSGA-II) and multiple objective particle swarm optimization (MOPSO) algorithms. The multi-objective ORC design obtained with the OPSSAJ yields a significant improvement in thermal efficiency and cost values compared to designs found by the NSGA-II and MOPSO algorithms. Furthermore, a sensitivity analysis is performed to observe the influences of the selected design variables on problem objectives.

Cost management of a construction company based on functional cost analysis

In conditions of environmental instability and uncertainty, one of the factors for the effective functioning and development of a construction company is high-quality and continuous cost management. The cost management process is aimed at maximizing profits by increasing the efficiency of the use of all resources. It requires constant monitoring to make adjustments to the planned costs and their amounts. Cost management is impossible without careful analysis. Along with the traditional methods of cost management, it is advisable for construction companies to apply functional cost analysis, which is an effective tool for optimizing costs and the quality of production functions performance. The research studies a construction company. Particular attention in the study is paid to indirect costs due to an increase in their share in the structure of the construction products cost. Within the framework of the functional cost analysis, an ABC analysis was carried out and a Pareto curve was modelled. It allowed us to focus on the allocated cost areas and classify the processes into main, basic and supportive ones. The significance of the identified processes was determined using the paired comparisons method. The results obtained allow us to draw a conclusion about the correspondence of the share of cost items and their significance for the analyzed construction company. The research materials are of interest and practical importance for the CEOs of construction companies.

Aplikasi Desain Faktorial 23 pada Kadar CO2 Proses Purifikasi Bio-gas dengan Adsorben Genteng - Zeolite

The CO2 content in biogas is an impurity, so it needs to be reduced. One way to reduce the levels of CO2 in biogas is by purification with tile-zeolite adsorbents. The purpose of this study was to determine the use of tile - zeolite as an adsorbent in the purification process to reduce CO2 levels using a 23 factorial design. The use of tile powder adsorbents (25% and 75%) - Zeolite (75% and 25%), biogas flow rates of 1 and 6 liters/minute, which were investigated at intervals of 5 and 20 minutes, to collect CO2 content data. Gas Chromatography-Mass Spectrometry (GCMS) is used to test the adsorption gas content. The results are shown by the Pareto curve resulting from biogas purification of CO2 levels, each of which has a magnitude of response to CO2 levels. Increased levels of tile-zeolite as an adsorbent and the rate of biogas flow in the purification process had an effect of reducing CO2 levels by 44.214%. Conversely, an increase in tile-zeolite levels as an adsorbent increases CO2 levels in the biogas purification process. Natural tile is a porous material that can adsorb and has ions that can be exchanged with ions from the outside.

Size Distribution of States, Counties, and Cities in the USA: New Inequality Form Information

In this article, we propose a new approach for studying the patterns of size distribution in settlement systems, based on the analysis of the shape of the Pareto curve (PC). To study the shape of the PC, we used the Gini coefficient, the asymmetry coefficient, and, by analogy with the physics of phase transitions, critical exponent — the index of the PC degree in the neighborhood of zero. An empirical analysis of the PC of various levels of aggregation in the US settlement system has been performed. The form of size distribution of states was studied by decades from 1790 to 2010. The spatial analysis of the PC shape for counties and cities was performed for 2010. The results of an empirical study showed that the PC of the states had left-hand asymmetry over 220 years. The PC of districts and cities had both right-hand and left-hand asymmetries. The obtained results explain in which cases the Pareto distribution having a PC with right-hand asymmetry, and the lognormal distribution with a symmetric PC may not correspond objectively to real settlement systems. As an alternative to power-series distribution and lognormal distribution, we considered an analytically simple two-parameter model with a wide range of PC asymmetry that combines the properties of power-series distribution and lognormal distribution. Verification of the model showed that it adequately described the size of settlements in homogeneous settlement systems.