Proposed Modeling Tool Research Articles

Solubility Measurement and Modeling of 5-Methyl-2-[(2-nitrophenyl)amino]-3-thiophenecarbonitrile (Y Form) in Pure and Binary Solvents

5-Methyl-2-[(2-nitrophenyl) amino]-3-thiophenecarbonitrile, known as ROY for its red, orange, and yellow crystal colors, has attracted great attention for its rich polymorphism and has been widely adopted as a benchmark compound in crystallization studies. Form Y of ROY is the most stable polymorph at low temperature. Solubility of form Y in six pure solvents (methanol, ethanol, ethyl acetate, acetic acid, acetone, and DMSO) at different temperatures within a range of 292.15 to 334.15 K as well as in four organic (methanol, ethanol, acetone, DMSO) aqueous binary mixtures at different solvent compositions and a temperature of 301.15 K were determined via a UV spectrophotometric method. The experimental solubility data were modeled applying a state-of-the-art semi-predictive model: the PC-SAFT equation-of-state. Both the measured data and the proposed modeling tool could further facilitate studies on solvent screening and polymorphic control for the solution crystallization of ROY.

A symbiosis between cellular automata and dynamic weighted multigraph with application on virus spread modeling

The pattern of coronavirus spread at different geographical scales verifies that travel or shipment by air, sea or road are potential to transmit viruses from one location to somewhere far away in a very short time. Simulation and analysis of such a situation requires the development of models that support long distance transmission of viruses. Cellular Automata (CA) are a family of spatiotemporal computational models frequently employed in analysis of biomedical systems. A CA consists of a topological combination of units called cells as well as a transition function that propagates the configuration of cells locally and step by step. In this paper, we first present some patterns that show the local interaction between CA cells is not sufficient for virus spread modeling, especially at large spatial scales. Then, we generalize the concept of CA by providing a symbiosis between the neighborhood relationship of cells and the transmission channels represented by a dynamic weighted multigraph. Furthermore, we characterize the capabilities of the proposed modeling tool in simulation of the virus spread, and estimating the risk control during the movement restrictions and related health protocols. Finally, we simulate the coronavirus outbreak in the five study areas including three states and two countries. Our experiments using the proposed model verify that the proposed model is capable of formulating different ways of virus transmission, including long-distance transmission, and supports high-precision simulation of the pandemic.

Characterizing the regional concentrations and seasonality of the emerging pollutant decamethylcyclopentasiloxane (D5) using a WRF+CHIMERE modeling approach

In this study, the results from two passive air sampling campaigns (winter and summer) performed previously in 8 different urban sites allowed the inclusion of the volatile methyl siloxane (VMS) D5 in a chemistry transport model (WRF+CHIMERE modeling system) to assess its performance in describing the concentrations and seasonal distribution of this emergent contaminant in a domain covering the western Iberian Peninsula. The model estimations were evaluated using the available field-based data, and the WRF+CHIMERE approach showed, in general, errors under 50% for all sampling sites and seasons, with a slight tendency to underestimations of D5 concentrations when using the lowest emission factor among those selected from the literature and to very large overestimations when using the highest emission factor available. The greatest errors are found for remote sampling points (substantial overestimations of the models at Midões, by even a factor of 3) and for coastal ones (where population and therefore emissions exhibit strong seasonality). The results also indicate that the chemical sinks by OH degradation play a negligible role on the ground-level concentrations of D5 at the scale of the investigated domain, with average contributions under 0.5%. Despite the lack of data regarding D5 emissions in the area, which led to the assumption of emission rates taken from other countries (and a constant population in the domain), the results of this first study are excellent and highlight the skill of WRF+CHIMERE in reproducing D5 concentrations. Indeed, the nature of the proposed modeling tool is helpful for understanding the processes conditioning the present and future behavior of contaminants like D5. Moreover, the model is bound to allow the future inclusion of D5 (and other VMSs) in regulatory scenarios, since restrictions on the use of these chemicals have just started to be introduced.

Analysis and Design Guidelines for Current Control Loops of Grid-Connected Converters Based on Mathematical Models

Having a method for analyzing and designing regulators of controls that contain many current loops such as active filters is not a trivial task. There can be many parameters of regulators and filters that must be carefully selected in order to fulfill certain desired requirements. For instance, these can be stability, dynamic response, robustness under uncertainty of parameters, and rejection capability to switching harmonics. Hence, this paper provides general analysis guidelines for designing current control loops by using mathematical models in an αβ reference frame. Then, by using the proposed modeling tool, a multi-objective tuning algorithm is proposed that helps obtain all the control loops’ regulator and filter parameters, meeting all the desired requirements. Thus, the proposed analysis and design methodology is illustrated by applying it to three different controls conceived in a dq rotating reference frame with PI (Proportional Integral) regulators. The first control presents two current loops (simple dq current control), the second control uses four current loops (dual vector control, for unbalanced loads), while the third control presents eight current loops (active filter controlling current harmonics). Several experimental and simulation results show the effectiveness and usefulness of the proposed method. Since the mathematical model employed is in the αβ reference frame, it can also be easily applied to controls conceived in a αβ reference frame using resonant regulators, providing also a common comparative framework.

Impedance Circuit Model of Grid-Forming Inverter: Visualizing Control Algorithms as Circuit Elements

The impedance model is widely used for analyzing power converters. However, the output impedance is an external representation of a converter system, i.e., it compresses the entire dynamics into a single transfer function with internal details of the interaction between states hidden. As a result, there are no programmatic routines to link each control parameter to the system dynamic modes and to show the interactions among them, which makes the designers rely on their experience and heuristic to interpret the impedance model and its implications. To overcome these obstacles, this article proposes a new modeling tool named as impedance circuit model, visualizing the closed-loop power converter as an impedance circuit with discrete circuit elements rather than an all-in-one impedance transfer function. It can reveal the virtual impedance essence of all control parameters at different impedance locations and/or within different frequency bandwidths, and show their interactions and coupling effects. A grid-forming voltage source inverter is investigated as an example, with considering its voltage controller, current controller, control delay, voltage/current dq-frame cross-decoupling terms, output-voltage/current feedforward control, droop controllers, and three typical virtual impedances. The proposed modeling tool is validated by frequency-domain spectrum measurement and time-domain step response in simulations and experiments.

A preliminary model to evaluate disaster management efforts.

Disasters are diversified in all aspects: they range from storms and tornadoes to earthquakes, tsunamis and cyclones etc. They affect a range of countries. Most disasters are caused by geographical factors. The overall response depends on the wealth of a country. For example, Japan is better prepared than Nepal or Haiti. Disaster responses are multidimensional and are assumed to be effective. From a service quality perspective, groups of responders provide services to victims. Effectiveness and efficiency of victim services are perhaps two outcome measures. Unfortunately, published studies on evaluation of disaster responses are sparse to nonexistent. The intent of this study is to develop a preliminary method for assessing the perceived effectiveness and efficiency (service quality) from the perspectives of both the responders and the victims. A method (preliminary) is proposed in which all anticipated attributes and outcomes are measured. Regression is the proposed modeling tool. It is hoped that the proposed preliminary method will facilitate the preparedness of the response teams and give rise to a permanent method.

Modeling electrokinetic transport and biogeochemical reactions in porous media: A multidimensional Nernst–Planck–Poisson approach with PHREEQC coupling

Electrokinetic techniques (EK) have been proposed and applied in different fields of science and engineering to enhance solute transport and species mobility in subsurface porous media. Modeling of EK requires a comprehensive approach allowing the description of the complex interplay between physical, chemical and biogeochemical processes occurring in EK applications. We propose a multidimensional modeling approach that allows the integrated description of fluid flow, solute transport (including electromigration and electroosmosis), Coulombic interactions between transported species, and a wide range of kinetic and equilibrium reactions. The proposed modeling tool, NP-Phreeqc-EK, is a coupling between COMSOL Multiphysics, which is used to solve fluid flow and solute transport in saturated porous media based on a Nernst–Planck–Poisson formulation, and PhreeqcRM, used to solve geochemical reactions. We illustrate the capabilities of NP-Phreeqc-EK with selected benchmarks in domains with different dimensions (1D, 2D and 3D). The results of the model are successfully compared with analytical solutions, numerical simulations with other software, and data from previously published EK-experiments. The outcomes of this study show the flexibility of the approach in simulating electrokinetic reactive transport processes in saturated porous media and highlight the importance of Coulombic interactions in EK applications. Such electrostatic interactions can strongly impact the performance of EK techniques since they affect the displacement velocities of charged species and can limit the maximum concentration of amendments that can be delivered through electromigration.

A Robust Method for Diagnostic Energetic System with Bond Graph

Surveillance and supervision systems have a major role in insuring the safety and availability of industrial equipments and installations. Default detection and diagnosis is highly important to facilitate the planning and implementation of curative and preventive actions. Industrial systems are usually governed by different physical phenomena’s and diverse technological components. Bond graph, being a powerful tool based on energetic and multi-physical analysis can be a well-adapted tool in default detection. The resulting Bond Graph model, allows to apply model based diagnosis methods to detect and eventually isolate defaults. In this paper, energetic systems diagnosis problems are discussed by detailing existing diagnosis methods. The proposed modeling tool is then introduced with illustration of different use cases and applications examples. Diagnosis methods based on Bond Graph model are presented, as well as the extension of these methods with uncertain parameters models. Finally, the studied diagnosis method is applied for default detection and isolation using the study case of asynchrony motor.

Многомодельная Оценка Инновационного Развития 78 Российских Регионов По Опережающим Индикаторам За Период 2005–2017гг. (Multimodel Estimation for Innovative Development of 78 Russian Regions Using Leading Indicators During 2005-2017)

Russian Abstract: Предложен комплекс опережающих индикаторов инновационной динамики России и их многокомпонентные оценки для 78 регионов за период 2005-2017 годов. Индикаторы характеризуют динамику основных отраслей российской экономики (строительства, торговли, добычи полезных ископаемых, обрабатывающей промышленности) трендами, циклическими, сезонными колебаниями и их взаимодействиями. Динамика продукции сельского хозяйства, в большей степени обусловленная климатическими и природными условиями, пока не рассматривались. Для трендов индикаторов предложены одна линейная и шесть существенно нелинейных (нелинейных по параметрам) моделей. Сезонная компонента моделировалась гармоникой с сезонными коэффициентами, а циклы Китчина, Жугляра и Кузнеца - суммой гармоник с некратными частотами (по Е.Е. Слуцкому). Взаимодействие компонент рассматривалось как линейное (аддитивной), так и нелинейное (аддитивно-мультипликативное). Скорректированный коэффициент детерминации обосновал более точные модели. Было уделено внимание расширению адаптации инструментария, прогнозированию всех регулярных компонент индикаторов, характеристикам инновационного развития и синхронности циклов отдельных регионов. Представлен новый и большей точности материал для руководителей, служб и предприятий регионов, определены дальнейшие перспективы развития предложенного инструментария. English Abstract: The authors proposed a set of leading indicators of innovation dynamics in Russia and their multicomponent estimates for 78 regions during 2005-2017. The indicators show dynamics of the most important economic sectors in Russia (building, trade, mining, manufacturing and its branches) while agricultural production, which dynamics mostly depends on climate and geography, have not yet been considered The models include trends, cycles, seasonal component and their interactions. For trends one linear and six substantially nonlinear (nonlinear in the parameters) models are used. The seasonal component was modeled by seasonal coefficients. Kitchin, Juglar and Kuznets cycles was modeled using sum of three sine curves with non-proportional frequencies (as suggested by E.Slutsky). The interaction of components was considered both linear (additive) and nonlinear (additive-multiplicative). The most accurate models were justified using adjusted coefficient of determination. Special attention is paid to adaptive modeling tools expansion, leading indicators decomposition and forecasting, innovative development analysis and regional cycles synchrony or asynchrony. As a result of the modeling the authors presented new and more accurate material for regional authorities and managers. Further development of the proposed modeling tools are also suggested.

INTEGRATED REMOTE SENSING AND GIS FOR MODELING ECONOMIC REHABILITATION DEVELOPMENT OF EX-MINE SITES

The potential environmental impacts of mining, increasing environmental legislation and public awareness have received increased attention world-wide in the last two decades. The focus of concern by the industry, environmental regulatory agencies and members of the public is the systematic rehabilitation of ex-mine sites to improve the quality at site for potential future commercial land use. The minerals extracted from these mine/quarry sites are essential in the construction, semiconductor, high-technology, ceramic and other manufacturing sectors for further industrial development. However, efficient engineering design and systematic economic evaluation of mine sites for site rehabilitation are required in maintaining the expected standards of environmental compliance. With escalating production costs and the keen competitiveness of the mining industry world-wide, the necessity to increase the efficiency in site rehabilitation is getting more prominence. A coordinated environmental protection and rehabilitation programme is essential if the environmental awareness of the community and the demands of the respective planning authorities are to be accommodated. There is thus a need to increase the base of knowledge for efficient planning in the systematic and progressive rehabilitation of current and future ex-mine sites. An efficient modeling tool is required for the systematic planning and design of potential economic land development of ex-mine sites. The applicability of Remote Sensing and Geographic Information System (GIS) technology is a useful tool to acquire spatial information for the systematic design and planning of potential development of ex-mine sites. This research was conducted to detect the trends in the suitability of land cover changes via land cover change detection of ex-mine sites and validated with reality. The findings are useful to assist in the development of a tool for efficient modeling and design of potential economic development of ex-mine sites. The aim of this research is to quantify, model and map the economic potential of the ex-mine sites for built up areas such as housing and other urban infrastructures. Land cover classes were interpreted into maps and the accuracy of the maps were validated to reference data and actual ground scenarios. The study for validation of the proposed modeling tool was carried out using the large prominent mining area in Malaysia namely the Kinta District. Results from the validation study carried out indicate that the correlation of the results obtained from this Integrated Remote Sensing and GIS tool for modeling to field data is in the range of 0.87-0.92 which is acceptable and close to reality.

BANKS FINANCIAL SECURITY MANAGEMENT: MODELING TOOLS

The article is devoted to the development of the complex of economic and mathematical models to support decision–making on managing commercial banks financial security. Aggregated model of management system of commercial banks financial security is presented. Basic conceptual scheme of the bank’s financial security management is developed.The proposed modern modeling tools on the bases of multivariate, econometric, simulation methods and decision making methods make possible to do integrated complex analysis at all levels of the banking market. The results of research in particular assessment and analysis of the survival and spread of crises in the banking market, the research of the particular bank financial security level dynamics in terms of external and internal factors are the basis for the formation and selection of scenarios of financial security ensuring taking into account the features, opportunities and competitive advantages of each bank. The implementation of the proposed modeling tools of financial security makes possible to improve the efficiency and effectiveness of the commercial bank activity and its financial security level.

Influence of solder bump arrangements on molded IC encapsulation

This paper presents a fluid–structure interaction (FSI) analysis of ball grid array (BGA) package encapsulation. Real-time and simultaneous FSI analysis is conducted by using finite volume code (FLUENT) and finite element code (ABAQUS), which are coupled with MpCCI. A BGA integrated circuit (IC) package with different solder bump arrangements is considered in this study. In the FSI analysis, effects of solder bump arrangements on pressure distribution, void, deformation, and stress imposed on the IC structures are investigated. The maximum deformation and maximum stress on the silicon chip and solder bumps are evaluated. The findings indicate that the full-array solder bump package encounters lower stress and deformation during encapsulation. The void formation of each solder bump arrangement is examined. Scaled-up encapsulation is performed and the predicted flow front advancements are substantiated by experimental results. Results demonstrate the excellent capability of the proposed modeling tools for predictive trends of IC encapsulation. Thus, better understanding of IC encapsulation is provided to engineers and package designers in the microelectronics industry.

Effect of Road Grade on Networkwide Vehicle Energy Consumption and Ecorouting

Because of growing concern about the impact of emissions from the transport sector on global climate change, vehicle energy consumption is a factor of great interest to network planners. In addition, drivers are interested in reducing energy consumption and, thus, fuel costs. However, traditional models of vehicle energy consumption have neglected an important factor: road grade. This assumption has traditionally been supported by the idea that the energy consumed because of the road grade would be reflected in changes in speed and acceleration, but a demonstration of this on an aggregate network in a city of a realistic size has been difficult to show. This work demonstrated the impact of road grade on networkwide vehicle energy consumption by the integration of energy consumption equations based on road load equations, elevation data available from the Google Elevation advanced programming interface, and a dynamic traffic assignment model to capture the effect of user route choice. This work quantified the impact of the energy consumed because of road grades on two city networks, and the results indicate that the effects of grades should not be excluded from evaluations of vehicle energy consumption. In addition, the effects of eco-routing, in which drivers choose the shortest path that consumes the least amount of energy, were explored. The results for the city networks indicate that if drivers do not account for grades, they might choose a route that actually increases vehicle energy consumption. The proposed modeling tool is scalable and easily adaptable to different cities.

The Real Cost of a CPU Hour

IT organizations can now outsource computer hardware by leasing CPU time through cloud computing services. A proposed modeling tool can quantitatively compare the cost of leasing CPU time from these online services to that of purchasing and using a server cluster of equivalent capability.

A Unified Approach for Modeling CVD Processes

A modeling technique based on bond graph methods was proposed for the analysis and understanding of chemical vapor deposition (CVD) processes. In contrast with pure numerical techniques, the proposed modeling tool provides an understanding of the behavior of the process and an appreciation of interactions between the various phenomena in the system. The essential bond graph tools required for modeling any CVD system were developed. Furthermore, since the tools are not system specific, the development of a general computer program capable of modeling any complex CVD process was facilitated. The modeling power of this new method was illustrated through a study of deposition process using tetraethoxysilane. The bond graph method allowed repeated guesses at the phenomena with minimal effort and resulted in an enhanced understanding of the process. In addition, the application of the bond graph method as an analytical tool for CVD processes where the physics of the phenomena is known is illustrated through several hypothetical examples.

Synchronization and storage models for multimedia objects

A technique is presented for the formal specification and modeling of multimedia composition with respect to intermedia timing. The proposed model is based on the logic of temporal intervals and timed Petri nets. A strategy is evinced for constructing a database schema to facilitate data storage and retrieval of media elements based on the temporal relationship established by the proposed modeling tool. An algorithm which allows the retrieval of media elements from the constructed database in a manner which preserves the temporal requirements of the initial specification is presented. Using the proposed model, the synchronization requirements of complex structures of temporally related objects can be easily specified.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>