Tool For Analysis Of Systems Research Articles

Global sensitivity analysis of structural models by active subspace and neural network

PurposeGlobal sensitivity can measure the influence of input variables on model responses and is of positive significance for the improvement design of structural systems. This work aims to study the global sensitivity of structural models by combining the active subspace theory and neural network.Design/methodology/approachThis study aims to improve the efficiency of global sensitivity analysis for high-dimensional structural systems, a novel method based on active subspace and surrogate model is proposed. Active subspace can reduce the dimension of input variables, and an adaptive scaling strategy is proposed to improve the accuracy in finding the active subspace. The uncertainty propagation of active variables and model response is performed through the artificial neural network. Then the global sensitivity analysis is carried out.FindingsSeveral examples are studied by using the Monte Carlo simulation method and the proposed method. Comparison of the results shows that the proposed method has preferable accuracy and low computational cost.Originality/valueThe proposed method provides a practicable tool for the variance-based sensitivity analysis of structural systems. Apart from sensitivity analysis, the method can be also extended for use in other fields relating to uncertainty propagation.

Rancang Bangun Sistem Informasi Pengarsipan di PLN Rayon Rancaekek

In today's era, information systems are an important factor in a company, one of which is in the field of archiving. Archiving at the State Electricity Company (SEC) Rayon Rancaekek still uses a semi-computerized method, which raises several problems, namely difficulty in finding data, not yet integrated transaction files with reports so that reports cannot be generated automatically, the length of the data calculation process because it is still done manually, there is a risk of data being double input and deleted, as well as lost or damaged documents. The purpose of this final project is to simplify data retrieval, integrate transaction files with reports so that reports can be presented after the transaction process, streamline the calculation of archived data, avoid double input and deleted data, and anticipate lost or damaged documents. The research and system development method used is the System Development Life Cycle (SDLC) with the Waterfall model. This system is made using Microsoft Visual FoxPro 9.0 and FoxPro database. System analysis and design tools used in this final project are Flow map, Data Flow Diagram (DFD), Entity Relationship Diagram (ERD), database relation schema, and Structure Chart. With the system design made, it can be concluded that the search for archive data becomes easier, all files are integrated so that reports can be presented at any time, the data calculation process can be carried out more effectively, double input data and the risk of data loss can be anticipated, as well as loss and damage data can be anticipated.

Mathematical model of a microbial electrosynthesis cell for the conversion of carbon dioxide into methane and acetate

CO2 conversion to methane and short-chain carboxylic acids in a microbial electrosynthesis cell (MESC) is an emerging approach for combining CO2 sequestration with the production of valuable commodities from a renewable source of carbon. While the production of CH4 and carboxylic acids, such as acetate, was demonstrated in several studies, process scale-up requires a simulation tool for a thorough system analysis, optimization, and a techno-economic assessment. The dynamic mathematical model developed in this work simulates the production of H2 via electrochemical and bio-electrochemical pathways and the formation of CH4 and acetate from CO2 at the MESC cathode taking into account the non-linear dynamics of microbial growth and CO2 conversion, the effects of various operating conditions, and CO2 transport between the MESC electrode compartments. Furthermore, the model simulates the growth of the three key biomass populations of acetogenic, methanogenic and electroactive microorganisms. Parameter identification followed by model validation demonstrated a reasonable agreement between the model predictions and the experimental results. The model was used to predict changes in CH4 and acetate production in response to changing MESC operating conditions.

A Sensitivity-Based Three-Phase Weather-Dependent Power Flow Algorithm for Networks with Local Voltage Controllers

Local voltage controllers (LVCs) are important components of a modern distribution system for regulating the voltage within permissible limits. This manuscript presents a sensitivity-based three-phase weather-dependent power flow algorithm for distribution networks with LVCs. More specifically, the proposed algorithm has four distinct characteristics: (a) it considers the three-phase unbalanced nature of distribution systems, (b) the operating state of LVCs is calculated using sensitivity parameters having accelerated convergence, (c) it considers the precise switching sequence of LVCs based on their reaction time delays, and (d) the nonlinear influence of weather variations in the power flow is also taken into consideration. Simulations and validation results presented indicate that the proposed approach outperforms other existing algorithms with respect to the accuracy and speed of convergence, thus making it a promising power flow tool for accurate distribution system analysis.

Bulk automated analysis of variability of nucleosome structures and their complexes

The cryo-EM revolution is now driving the progress in our understanding of chromatin structure by solving the structures of nucleosomes and their complexes. The number of structures in the PDB database has doubled over the last three years and is rapidly growing. However, harnessing helpful information from this wealth of structural 3D data is challenging. Variations in components’ naming nomenclature, chain identifiers, amino acids, and nucleotide numbering and lack of readily available tools for systematic structure analysis and comparison adds to the complexity of the problem.

Analysis of social vulnerability index in Watershed Bengawan Solo downstream

Purpose of this research to know 1) the level of social vulnerability, 2) socio economic description, and 3) mapping of comparison of social vulnerability in Watershed of Bengawan Solo covering Bojonegoro, Tuban, Lamongan and Gresik. The method used in this research by using Social Vulnerability Index (SoVI) method as social vulnerability analysis tool and Geography Information System (GIS) analysis tool to map the area and its vulnerability level. The results showed the highest level of social vulnerability with the highest score of SoVI score obtained by Tuban Regency with SoVI score of 7, then Bojonegoro with SoVI score of 6, Lamongan with SoVI score of 4, and Gresik with SoVI score of 1. Bojonegoro And Kabupaten Tuban have the same highest score on the components of social vulnerability level, then Lamongan regency, and the lowest level of social vulnerability is in Gresik regency. For the grade of social vulnerability, Kabupaten Tuban and Bojonegoro are categorized into high social vulnerability classes, Lamongan District with moderate social vulnerability, and Gresik Regency with the lowest social vulnerability.

СЕЛЬСКАЯ ТЕРРИТОРИЯ КАК СИСТЕМА ВЗАИМОДЕЙСТВИЯ ЭКОНОМИЧЕСКИХ И СОЦИАЛЬНЫХ ПРОЦЕССОВ

The article deals with the problems of interaction of economic and social processes in rural municipal areas, which is a determining factor in the quality of life of the rural population. The aim is to study on the basis of constructive simplification of the territorial system the allocation of its subsystems for separate study. The criterion for such allocation is to take into account the main links considered by the economic and social subsystems with the structure of the system as a whole. Rural territory can be represented in the form of interconnected spatial subsystems of the following: agricultural production, household, service, transport and information communications. At the same time, the potential for consumption of material and spiritual goods can be considered from the standpoint of three types of social accessibility: material, spiritual and spatial-temporal. It is revealed that the main disproportions in the modern development of rural areas are the disproportions between the potential of consumption, on the one hand, and the level of actual availability of material and spiritual goods, on the other. To eliminate these imbalances, it is advisable to use system analysis tools that allow you to obtain the necessary information about the interaction of social and economic factors. At the same time, the study of current trends in the interaction of economic and social processes that determine the standard of living of the rural population shows that the placement of capital investments within a rural municipal district should be based on a comprehensive cost-effectiveness analysis, since the evaluation of the effectiveness of investments for individual objects does not take into account the interrelationships, interaction and synergetic effect of socio-economic factors affecting the qual

ВИКОРИСТАННЯ МЕТОДІВ СИСТЕМНОГО АНАЛІЗУ ПРИ ДОСЛІДЖЕННІ ПРОБЛЕМ ІНТЕЛЕКТУАЛЬНИХ ТРАНСПОРТНИХ СИСТЕМ

This article discusses the use of systems analysis to study the problems of intelligent transport systems. The main problems of transport systems are identified and the main functions of intelligent transport systems are given. The object of research is intelligent transport systems. The purpose of the study – to analyze the feasibility of using methods of systems analysis in the study of problems of intelligent transport systems. The main advantage of intelligent transport systems is the simulation of various events and forecasting of dangerous situations. These systems are an important component of a systematic approach to improving the efficiency of the country's transport system. The lack of research in the field of ITS, implemented using methods and tools of systems analysis, indicates the relevance of this study. It is established that intelligent transport systems are an important component of an integrated approach to improving the efficiency of the transport system with a significant expansion of information infrastructure: collection, transmission, processing and storage of information about the transport system in real time and operational dispatch coordination. KEY WORDS: TRANSPORT, TRANSPORT PROBLEMS, SYSTEM ANALYSIS, SYSTEM APPROACH, TRANSPORT SYSTEMS, INTELLIGENT TRANSPORT SYSTEM.

Is Sociodemographic Status Associated with Empathic Communication and Decision Quality in Diabetes Care?

ObjectiveTo assess the relationship between empathic communication, shared decision-making, and patient sociodemographic factors of income, education, and ethnicity in patients with diabetes.Research Design and MethodsThis was a cross-sectional study from five primary care practices in the Greater Toronto Area, Ontario, Canada, participating in a randomized controlled trial of a diabetes goal setting and shared decision-making plan. Participants included 30 patients with diabetes and 23 clinicians (physicians, nurses, dietitians, and pharmacists), with a sample size of 48 clinical encounters. Clinical encounter audiotapes were coded using the Empathic Communication Coding System (ECCS) and Decision Support Analysis Tool (DSAT-10).ResultsThe most frequent empathic responses among encounters were “acknowledgement with pursuit” (28.9%) and “confirmation” (30.0%). The most frequently assessed DSAT components were “stage” (86%) and knowledge of options (82.0%). ECCS varied by education (p=0.030) and ethnicity (p=0.03), but not income. Patients with only a college degree received more empathic communication than patients with bachelor’s degrees or more, and South Asian patients received less empathic communication than Asian patients. DSAT varied with ethnicity (p=0.07) but not education or income. White patients experienced more shared decision-making than those in the “other” category.ConclusionsWe identified a new relationship between ECCS, education and ethnicity, as well as DSAT and ethnicity. Limitations include sample size, heterogeneity of encounters, and predominant white ethnicity. These associations may be evidence of systemic biases in healthcare, with hidden roots in medical education.

RISE-Based Trajectory Tracking Control of an Aerial Manipulator Under Uncertainty

This study presents a robust integral of the sign of the error (RISE)-based controller for an aerial manipulator consisting of a multi-rotor and a robotic arm which guarantees tracking error convergence to zero in the presence of uncertainties. To rigorously address underactuatedness issue, the system dynamics is decomposed into the two subsystems for which a robust controller is derived. As an intermediate result, if there exists no uncertainty, we show that the nominal closed-loop system with the proposed nominal controller is asymptotically stable without assuming that the attitude error term in the underactuated part is zero by cascaded system analysis tool. Then, a robust controller combining a nominal controller and a RISE controller is proposed and applied to both subsystems. Tracking error convergence is strictly proved through Lyapunov-based stability analysis. The performance of the controller is demonstrated in simulation with comparative studies where the proposed controller outperforms the other compared controllers in error convergence.

ПРИКЛАДНОЙ СИСТЕМНЫЙ АНАЛИЗ И СИСТЕМОТЕХНИКА КАК ИНСТРУМЕНТЫ ОПТИМИЗАЦИИ ЭКОНОМИЧЕСКИХ ПРОЦЕССОВ

Applied system analysis becomes an integral part of the competencies of a modern specialist, regardless of the branch of his activity or his position in the company. This is due to the fact that the system approach allows you to quickly and efficiently understand the structure of the system, the features of its functioning, to determine the nature of the mutual influence of its elements on each other. Existing system analysis tools help to build a convenient model for analyzing the past, present and predicting the future scenario of achieving certain goals.

Advanced Probabilistic Power Flow Method Using Vine Copulas for Wind Power Capacity Expansion

As the use of renewable energy is continuously increasing, power systems are currently exposed to greater uncertainty and variability, which can lead to severe power system stability issues. Therefore, a power system analysis tool should be devised to assess the impact of renewable energy integration along with an accurate modeling of their stochastic characteristics. In this study, an advanced probabilistic power flow (PPF) method is developed using vine copulas that captures the complex dependency of the stochastic wind power generated from multiple wind sites. The proposed method also involves the use of a function for selecting the probability models of wind speeds by regions in a sophisticated manner. The effectiveness of the proposed method is tested on an IEEE bus system as well as, on a South Korean power system with thousands of buses and transmission lines using PSS/E with Python API. The simulations demonstrate that the proposed method can more accurately evaluate the power system risks with the sophisticated modeling of wind power in multiple sites as compared to the deterministic approach or the PPF with independent sampling.

A Construction Method of Power Grid Monitoring Knowledge Graph

Centralized monitoring and integrated intelligent alarm functions have been implemented on the control system of smart power grid, which provides technical support for the judgment and disposal of power grid accident. However, there are still some problems such as lack of systematic analysis tools and cannot realize the correlation of alarms. This paper proposes a power grid accident analysis method based on monitoring information knowledge graph, which is constructed with power grid topology and historical alarm data rules. Using this method, the staff can accurately and quickly judge the power grid accident with the support of grid topology and alarm correlation, so as to improve the efficiency of power grid accident analysis and reliability of power grid control system.

Realistic Simulation Tool for practical Analysis of Solar Cooling Thermal Systems driven by Linear Fresnel Collectors

The objectives of this study were to develop a realistic simulation tool to analyze solar thermal cooling systems driven by Fresnel collectors and carry out a case study in which the performance of a solar cooling system of 190 kW located in Riyadh is simulated to demonstrate the functionality and potentiality of the developed tool. This tool is based on an integrated mathematical model that considers the ambient conditions, the thermal loads of the building, the pre-sizing data of each of the components of the system and the simultaneous interaction among them, to conduct a realistic, simple, and precise analysis. A demonstrative simulation example was performed. During the month of July, with a solar opening area of 704 m2 and a tank of 35200 L, a total amount of 47,5 MWh of cooling energy was obtained, with a reduced contribution of the auxiliary system (5,6 MWh) and a minimum number of solar collector system deactivation hours (0,7 %). The daily COP of the absorption machine remained above 0,69. The obtained results from the case study with the simulation tool allowed to verify its functionality, capabilities and correct operation to carry out hourly and parametric studies of this type of systems.

Системний аналіз процесів формування “зеленої економіки” в сучасних умовах

Проведено аналіз сучасних тенденцій цивілізаційного розвитку, що свідчить про нестійкість сучасних моделей економічного розвитку як на регіональному, так і на глобальному рівнях. Спільним недоліком цих моделей є абсолютизація економічного зростання в умовах нехтування соціальних і екологічних проблем. Обґрунтовано положення, що без урахування соціальних і екологічних чинників неможливо забезпечити сталий розвиток економіки на тривалу перспективу. Виокремлено низку глобальних проблем соціально-економічного розвитку на сучасному етапі: зміна клімату, екстенсивне використання природних ресурсів унаслідок прискореного зростання населення світу, яке супроводжується негативним впливом на довкілля.

Multi-vehicle assignment with elastic vehicle choice behaviour: Fixed-point, deterministic process and stochastic process models

New types of vehicles, such as electricity-powered and/or autonomous cars or buses, are under rapid development, but the time needed to turn the existing stock of traditional vehicles, such as privately-owned human-driven fossil fuelled passenger cars, will likely last several years during which mixed traffic is expected. Moreover, the likely effects of the introduction of such vehicles may not be necessarily positive. Thus, a careful analysis of their various impacts through well designed tools is needed. Main tools for transportation systems analysis are based on methods for travel demand assignment to a transportation network, commonly used to support transportation project assessment and evaluation.The original contribution of this paper is twofold. First, a modelling approach to multi vehicle type assignment is proposed, in this approach the user choice proportions among vehicle types available to users are the results of an explicit choice behaviour model instead of input data as in all existing papers on multi-vehicle assignment. This approach is applied for analysing assignment to transportation networks including Fixed-Point models for equilibrium assignment and Deterministic and Stochastic Process models for day-to-to dynamic assignment.Second, statistical methods are introduced to study the bifurcation of SP models, in order to account for the stochasticity of such models. In particular, the Hartigan’s Dip statistic, which measure the degree of unimodality of a distribution, showed to be the most effective one in identifying bifurcation in SP models.Fixed-point stability and bifurcation analysis are carried out too, and some simple numerical examples are also discussed.Reported results show that innovative vehicles with less impact on congestion than traditional ones may not have a positive effect on equilibrium stability since negative effect of reducing route choice dispersion may be compensate the positive effects on congestion.

Computational Tool for Determining the Model in Sequence Components of Overhead Transmission Lines

An indispensable element in addressing the current problem of non-ionizing electromagnetic pollution in the environment is a review of the levels of exposure to the electric and magnetic fields produced by the lines of electric power transmission and distribution systems. In order to establish the exposure levels, it is necessary to determine the model of the lines. Considering that a computational simulation is a helpful tool for power system analysis, this article presents a computational tool developed in Matlab App Designer for the model-in-sequence components of the parameters that make up a transmission line. This tool allows the user to work in a friendly and parameterizable environment according to the performed tests. In order to verify the tool’s performance, two case studies are implemented. The first one is for a transposed transmission line and the second one for a non-transposed transmission line. The results obtained are compared with commercial software, acquiring a maximum error of 0.16402 %.

Possibilities and constrains of crowdlending platform development

Subject. The article addresses crowdlending platforms as an alternative way to invest resources. Objectives. We focus on identifying opportunities and limitations for the development of crowdlending platforms. Methods. The paper draws on the systems analysis tools. It also applies a structure-behavior-result (SBR) model, which enables to characterize the external environment of crowdlending platforms to identify their opportunities and constrains. Results. We identify opportunities and limitations of stakeholders involved in the development of crowdlending, including investors, borrowers, operators of digital platforms, the State and banks. The paper shows that both the demand and supply for the development of crowdlending are created. However, the main limitations in the development of this type of activity are associated mainly with institutional factors. Transparency in the activity of crowdlending platforms will mitigate risks, increase the level of trust of owners and users of resources. The improvement of legislation in this field will help preclude misconduct of economic agents in using this tool. Conclusions. The findings can be used by federal and regional authorities in strategy implementation for the development of small and medium-sized businesses in the Russian Federation, as well as by bodies of legislative power in the development of regulatory framework for collective investment tools dissemination in Russia.

Considerations on the impact of battery ageing estimation in the optimal sizing of solar home battery systems

The exponential reduction in cost of photovoltaic panels and the forecasts projecting a similar behaviour for battery-based energy storage systems are driving increasing attention on residential energy systems based on photovoltaic (PV) panels and batteries. Such systems, if combined with demand electrification, could help decarbonising the sector and foster the adoption of distributed energy systems. In this work, a modular tool for the techno economic analysis of smart energy systems is applied to a case study in the residential sector. The considered system is composed by PV panels, battery, heat pump and air conditioning system. The tool integrates a method for the estimation of cyclic and calendric ageing of the battery. The effects of varying battery capacity and its maximum depth of discharge on its lifetime have been investigated. An optimization algorithm has been employed to find the battery capacity that maximizes net present value (NPV) for given battery prices and PV panels areas. Results have highlighted the impact of using ageing models on the economics of residential energy systems, suggesting that discontinuities might arise in the functions to be optimized, hence requiring more robust optimization algorithms. Results also suggest that not accounting for battery aging could lead to incorrect predictions regarding the economics of the system. The breakeven price for the introduction of batteries in residential energy systems is lower when using ageing algorithms, while, at the same time, higher optimal capacities have been obtained for lower battery prices.

A methodology to improve simulation of multibody systems using estimation techniques

ABSTRACT This paper presents a methodology for state estimation and accuracy improvement of computer simulations of computer aided engineering (CAE) models based on prediction and correction state estimation techniques and sensing. The aim is to simulate the dynamic behaviour of a real system, which can be sensed, and obtain values of states that are not measurable due to economic or technical limitations. This methodology can be applied to both optimization of design processes and on-line control of complex systems. State estimation techniques are currently used only on mathematical models, where the relationships among system variables are expressed by means of mathematical language, making state observer implementation possible but leading to limitations in system modelling and knowledge. Favoured over mathematical models, multibody CAE models (created by means of computer-aided engineering software) have become the essential tool for complex system development, simulation, analysis, optimization and control, such as multibody systems; one of their main advantages is the ease and flexibility in creating and modifying them, allowing the faithful modelling of complex systems.