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To enhance the quality and efficiency of computer-enabled generation of papers for Test for English Majors Band 8 (TEM-8), a paper generation model supported by sparrow search algorithm-genetic algorithm was studied. First, a simplified test paper generation mathematical model was set up after analyzing and studying types and characteristics of TEM-8 tasks. In the model, quantity, type, difficulty, discrimination degree, scores, exposure, and answering time of test questions were taken into consideration. To enhance the optimizing effect of the genetic algorithm for searching test questions, the traditional genetic algorithm was improved by introducing the sparrow search algorithm into the model to achieve a better crossover rate, variance rate, optimization precision, and speed of the genetic algorithm. A new sparrow search-genetic algorithm (SSA-GA) was designed, and the optimizing effect of SSA-GA was verified to be ideal through optimizing six standard test functions. Then, SSA-GA was applied to conduct experimentation with test paper generation, and comparison with traditional genetic algorithms was also made. The values of best and average fitness of SSA-GA were better than those of the traditional genetic algorithm (GA) in the paper generation. Exposure rate and success rate in TEM-8 paper generation of SSA-GA were higher than those of traditional GA in TEM-8 paper generation. Results showed that the studied SSA-GA could implement test paper generation with higher speed and better quality. [ABSTRACT FROM AUTHOR]

Drying of a coated paper is modeled and simulated. The paper sheet is assumed to form three zones, and each zone has its own drying mechanism. Coupling of energy and mass balances must be used in order to solve differential equations. The simulations are carried out in various drying conditions i.e., only hot air drying, only radiant drying, and mixed hot air-radiant drying. Also the effect of one side and two side assumption on evaporation is studied. Effect of venting air speed and radiant heat source presence and its distance from the drying surface on the drying of a coated paper has been studied. It is found that both distance and venting air speed are inversely related to drying in mixed hot air-radiant drying. Both surfaces participate in evaporation however, during the last time of drying, no difference between the upper and the bottom surfaces exist. [ABSTRACT FROM AUTHOR]

The increasing costs associated with water supply and the disposal of wastewater has stimulated industries to seek more efficient water management systems. Mathematical modelling and simulation can be a very valuable tool for the study of the multiple alternatives available whilst assessing optimum solutions for water management in industry. This study introduces a new steady state model library able to reproduce industrial water circuits. It has been implemented in a novel software framework for the representation, simulation and optimization of industrial water networks. A water circuit representing a paper mill has been modelled and simulated showing the capability to reproduce real case studies. Alternative scenarios for the water network have also been tested to assess the capability of the models to optimize water circuits minimizing total cost. [ABSTRACT FROM AUTHOR]

The article discusses the study which develops a dynamic modular paper machine simulator package. It has been noted that computer simulation can be a valuable tool for the optimization of paper production processes, designing wastewater closure strategies and the visualization of a complicated process. It shows that by structuring the simulator as a set of modular blocks, a variety of configurations can be modeled by assembling the blocks in different ways. In addition, researchers have recommended that the simulator package can help in developing simple models for the simulation of complex dynamic systems.

Abstract: A wide range of mathematical models for multiple effect evaporators in process industry including paper industry are well reported in the literature but not so extensive work on the dynamic behavior of MEE system is available in the literature. In the present study dynamic behavior of multi-effect evaporator system of a paper industry is obtained by disturbing the feed flow rate, feed concentration, live steam temperature and feed temperature. For this purpose an unsteady-state model for the multi-effect evaporator system is developed. Each effect in the process is represented by a number of variables which are related by the energy and material balance equations for the feed, product and vapor flow. A generalized mathematical model which could be applied to any number of effects and all kinds of feeding arrangements like forward feed, backward feed, mixed feed and spilt feed in the MEE system with simple modifications was finally obtained. Finally model for mixed feed sextuple effect falling film evaporators system was solved using MATLAB. For the steady state and dynamic simulation the ‘fsolve’ and ‘ode45’ solvers in MATLAB source code is used respectively. [Copyright &y& Elsevier]

Abstract: A new two-dimensional network model is proposed as a micromechanics model to simulate paper’s failure process due to sequentially breakages of fibers and/or bonds. Paper is approximated as a network composed of fibers any two of which link to each other by their intersecting point, namely so-called bond. Fibers distribute along three particular directions, leading to network’s macro-level isotropy. In the framework of finite element method, nodes correspond to fiber-to-fiber bonds, while elements are fiber segments between every two neighboring nodes and described by Timoshenko beam theory. Element breaks when its equivalent internal tensile stress reaches the tensile strength of fiber. Strength of nodes, i.e. fiber-to-fiber bonds is assumed to be dependant on shearing interaction between fibers, considering the dominant interaction is shearing in a plane problem. Numerical examples show the model’s capacity of reflecting basic failure characteristic in paper. Influences of fiber length and the ratio of fiber strength to bond strength are analyzed in detail. [ABSTRACT FROM AUTHOR]

Paper is a stochastic network of fibres, water and additives, and in that sense it may be envisaged as a composite material. Since fibres are much longer than the thickness of the paper sheet, the network is planar and almost two-dimensional. The two-dimensional structure governs many paper properties but the three-dimensional porous structure is also important. Insight into the structural changes that take place when paper is compressed in the paper machine may be gained by modelling and simulation of its viscoelastoplastic behaviour. The present work describes a mathematical model based on the cellular solids theory, characterising the nonlinear rheologic behaviour of the material. This approach results in an unsteady state problem and the resulting set of ODEs is solved by means of the DLSODES subroutine, which uses an integrator based in the Gear method. Experiments were conducted on a laboratory-scale dynamic press in order to validate the mechanical model. [Copyright &y& Elsevier]

A. V. Hill's 1938 paper ‘The heat of shortening and the dynamic constants of muscle’ is an enduring classic, presenting detailed methods, meticulous experiments, and the model of muscle contraction that now bears Hill's name. Pairing a simulation based on Hill's model with a reading of his paper allows students to follow his thought process to discover key principles of muscle physiology and gain insight into how to develop quantitative models of physiological processes. In this article, the experience of the author using this approach in a graduate biomedical engineering course is outlined, along with suggestions for adapting this approach to other audiences. [ABSTRACT FROM AUTHOR]

Abstract: This paper deals with a perfectly continuously monitored system which gradually and stochastically deteriorates. The system is renewed by a delayed maintenance operation, which is triggered when the measured deterioration level exceeds an alarm threshold. A mathematical model is developed to study the asymptotic behavior of the reliability function. A procedure is proposed which allows us to identify the asymptotic failure rate of the maintained system. Numerical experiments illustrate the efficiency of the proposed procedure and emphasize the relevance of the asymptotic failure rate as an interesting indicator for the evaluation of the control-limit preventive replacement policy. [Copyright &y& Elsevier]

This article presents a discussion on a study by Bradley Jones and Rachel T. Johnson on the use of Gaussian Process model in computer simulation research. The authors believe that the uncertainty intervals on unsampled points generated by using a plug-in approach from maximum likelihood estimates may be too short. Their own experiences confirm that computer models are widely used in many areas of science and engineering, and the need to understand the performance of such models is critical.

Abstract: We prove a theorem for the existence of solutions to a variational problem, under assumptions that do not require the convexity of the integrand. [Copyright &y& Elsevier]

This paper proposes a new method to improve re performance of intra-field interpolation which is the mos~ important element of deinterlacing method. Traditional edge- based methods were poor at determining accurate edge iirection which decides interpolation performance. The 7roposed method decides the direction and slope of edge based on locally adaptive-thresholded binary image to mprove efficiency and accuracy, and it also increased the ~orizontal size of search window to 15 for better direction ietermination at gentle slope. Compared to traditional edge- based methods, interpolation based on binary image, which is ,`enerated using the proposed method, leads to great erformance improvement. With computer simulations for a ~`ariety of images, this paper shows the new approach is much ~etter than traditional methods.. [ABSTRACT FROM AUTHOR]

This paper presents an implementation of an ~daptive beamformer in a hands-free unit. The proposec~ ~daptive beamformer suppresses stationary noise an~ nterference sound. The adaptive beamformer and acoustic `cho canceller were implemented in a compact hands-free mit with a low-cost DSP. Experimental results demonstrate he noise reduction performance of the hands-free unit'. [ABSTRACT FROM AUTHOR]

In this paper, we explore the consequences of a distinction between ‘live' and ‘dead' network nodes; ‘live' nodes are able to acquire new links whereas ‘dead' nodes are static. We develop an analytically soluble growing network model incorporating this distinction and show that it can provide a quantitative description of the empirical network composed of citations and references (in- and out-links) between papers (nodes) in the SPIRES database of scientific papers in high energy physics. We also demonstrate that the death mechanism alone can result in power law degree distributions for the resulting network. [ABSTRACT FROM AUTHOR]

The article is an editorial introducing a special issue of the scientific journal Axioms titled "Mathematical Models and Simulations." The issue contains 13 papers that cover various mathematical models and simulations in fields such as physics, biology, finance, and engineering. The papers explore different types of mathematical models, including deterministic and stochastic models, and discuss their applications and numerical simulations. The authors provide a brief overview of each paper, highlighting their main findings and methodologies. The article aims to provide library patrons with a concise summary of the special issue, allowing them to decide if they want to explore the individual papers further. [Extracted from the article]

The discrepancy between simulated and observed globally averaged monthly atmospheric concentrations of carbon dioxide could be attributed either to deficiencies in the observation network or to inadequacies in the global carbon cycle models. This paper shows that model results could be brought closer to observations by improving model components that describe the seasonal changes in the storage of quickly decaying fractions of litter. [ABSTRACT FROM AUTHOR]

This article presents a discussion on a study by Bradley Jones and Rachel T. Johnson on the use of Gaussian Process model in computer simulation research. The author believes that the Gaussian process model often performs adequately apparent nonstationarity. He explores the topic of model calibration, the relationship between the design and the model used to fit the data, and design augmentation.

This document is a summary of a special issue of the journal Mathematics, titled "Mathematical Modeling and Simulation in Mechanics and Dynamic Systems, 2nd Edition." The special issue focuses on the development of sophisticated models to predict phenomena in dynamic systems using experiments and computer models. The issue includes papers on topics such as modeling mechanical systems, new methods in dynamic systems, and the behavior simulation of mechanical systems. The papers were written by authors from 13 different countries, and the majority of the articles adhere well to the theme of the special issue. The document also provides a table showing the geographic distribution of authors by country. The authors of the special issue have made significant contributions to the field, and the document concludes by stating that the authors have no conflicts of interest. [Extracted from the article]

Abstract: In this paper we describe electrophoresis of charged particles in a thin layer of a nonpolar liquid between two insulating substrates because this configuration is common in recently developed in-plane electronic paper. In the in-plane electrophoresis experiments a model system of charged inverse micelles in dodecane has been used which is well understood from studies of out-of-plane electrophoresis. The transient current due to drift and diffusion of charged inverse micelles is measured in thin in-plane devices upon application of a voltage step. For the modelling of the transient dynamics of charged inverse micelles without chemical reactions or convection a 1-dimensional approximation of the Poisson–Nernst–Planck (PNP) equations is developed. This approximation is valid for a sufficiently thin in-plane device and allows much faster calculations. Firstly, it is verified in the case of a sufficiently thin in-plane device and high applied voltage that the 1-dimensional approximation is in good agreement with the solution of the full 2-dimensional PNP equations with finite elements implementation. Then, the 1-dimensional approximation is used to study the transient current and trajectories of trace amounts of charged colloidal particles in different regimes depending on the screening of the electric field. Also a comparison is made to the well-studied case of out-of-plane electrophoresis. Finally, it is verified that for voltages much larger than the thermal voltage the experimental results are in good agreement with the 1-dimensional approximation, indicating that the charge transport dynamics of charged inverse micelles in the bulk are described well by the model. [Copyright &y& Elsevier]

The article discusses the special issue's aim to provide a forum for the dissemination of modeling and simulation results in the field of medical image processing analysis particularly on efforts related to applications of computer vision, virtual reality and robotics to medical imaging problems.

The article presents a study which describes the application of SCanning Imaging Absorption spectroMeter for Atmospheric CHartographY (SCIAMACHY) lunar occultation water vapor measurements. The study illustrates the retrieval approach for radiative transfer model on the SCIAMACHY measurements. It also presents retrieval optimizations and sensitivity studies.

The article discusses the process of judging at the 2007 Interdisciplinary Contest in Modeling (ICM) of the Consortium for Mathematics and Its Applications (COMAP). The competing teams created mathematical models to tackle real world issues on the U.S. kidney transplant system. The judges assessed the papers on three important areas including the effective use of current information regarding the U.S. organ transplant network, appropriateness of model use, and integration of various disciplines including mathematics, science, and ethical principles. The article also discusses the criteria for the outstanding papers and the problems regarding plagiarism.

The article discusses the outstanding papers in the 2007 Interdisciplinary Contest in Modeling (ICM) of the Consortium for Mathematics and Its Applications (COMAP). The contestants used mathematical models to simulate the kidney transplant system in the U.S. The contest was won by a team from Duke University and another from Princeton University. It mentions that the topic of the contest, which is kidney transplantation and allocation, was very timely since policies on kidney transplants are rapidly changing with the help of mathematical models. The article declares that the two most outstanding papers clearly stated changes in the public policy and used correct analytical models to support their conclusions. Detailed discussion of the two papers is also presented.

The article presents the comments of the author on outstanding papers on wind and waterspray problems. The comments represented a compendium of observations during the final judging session and were taken in no particular order of preference or priority. Regarding the style and clarity of the papers, he said that the teams should bear in mind that they are writing to a population of modeling experts who have little time to read their papers. He commented on papers containing long list of assumptions, which he thinks neither get used nor justified in the modeling that follows.

This paper presents the results of mathematical simulation of processes in argon-hydrogen inductively coupled plasma/radio frequency induction plasma torch for plasma chemical reactions. This first part starts a series of papers for simulation and study of plasma properties for a variety of gases and mixtures, which could be used for a number of prospective technologies. The results of mathematical simulation allow further research on the mechanisms of chemical reactions in argon-hydrogen plasma to increase effectiveness of obtaining the target product. [ABSTRACT FROM AUTHOR]

In this paper, we improved a mathematical model of monkeypox disease with a time delay to a crossover model by incorporating variable-order and fractional differential equations, along with stochastic fractional derivatives, in three different time intervals. The stability and positivity of the solutions for the proposed model are discussed. Two numerical methods are constructed to study the behavior of the proposed models. These methods are the nonstandard modified Euler Maruyama technique and the nonstandard Caputo proportional constant Adams-Bashfourth fifth step method. Many numerical experiments were conducted to verify the efficiency of the methods and support the theoretical results. This study's originality is the use of fresh data simulation techniques and different solution methodologies. [ABSTRACT FROM AUTHOR]

In this paper, we consider a mathematical model which describes the equilibrium of two elastic rods attached to a nonlinear spring. We derive the variational formulation of the model which is in the form of an elliptic quasivariational inequality for the displacement field. We prove the unique weak solvability of the problem, then we state and prove some convergence results, for which we provide the corresponding mechanical interpretation. Next, we turn to the numerical approximation of the problem based on a finite element scheme. We use a relaxation method to solve the discrete problems that we implement on the computer. Using this method, we provide numerical simulations which validate our convergence results. [ABSTRACT FROM AUTHOR]

The article presents a study which applies the three-dimensional (3-D) Monte Carlo Radiative Transfer (MoCaRT) model in an effort to describe effects of cloud heterogeneity on radiances and broadband flux densities. The study performs 3-D radiative transfer simulations of nadir reflected radiances and computes spectral flux densities for the cumulus cloud's diurnal cycle. It also comprehensively describes the MoCaRT model.

The article presents a study which investigates the global and local properties of atmospheric aerosols through the Multi-Sensor Aerosol Products Sampling System (MAPSS). The study explores details of sampling concepts of MAPSS and possible applications of MAPSS. It concludes that MAPSS allows easy inter-comparison and validation of aerosols from multiple satellite sensors.

The article discusses the application of the Purdue model, a mathematical model, to simulate an industrial Lo-Solids pulp digester for Pinus radiata cultivated in Chile. It states that simulation results for pulp yield, free liquor temperature profile, and pulp production rate is validated by pulp mill data from the Arauco plant of Celulosa Arauco y Constitucion SA. Accordingly, researchers applied the mathematical model to simulate an increase in filtrate flow to the continuous cooking zone to save white liquor consumption. It mentions that results of the simulation shows a 9.1% savings of white liquor and a decrease in dissolved solids content, which proves that the pulping process of Lo-Solids improved.

The article presents the author's comments on several papers that gave the mathematical model for hurricane evacuation. The macroscopic approach taken by teams considered traffic on a particular highway to be a stream, and a flow rate for the stream was characterized. The microscopic approach taken by the teams was to use the spacing between and the speeds of individual vehicles to determine the flow. Many teams took the optimal flow from one of the macroscopic approaches and used it as the basis for a larger model. Many teams also used simulation models to determine evacuation times under a variety of scenarios.

The article presents the author's views on research papers related to elephant population. The focus of the research was to construct a mathematical model that measures the population growth of elephants under certain conditions. Different approaches, like analytic model, population model, and simulations, were employed by research teams to construct the model. In the beginning, the chief exercise was to develop a model that investigated the use of contraceptive darts in birth control.

Microscopic traffic models (MTMs) are widely used for assessing the impacts of (connected) autonomous vehicles ((C)AVs). These models utilize car‐following (CF) and lane‐changing models to replicate the (C)AVs driving behaviors. Numerous studies are being lately published regarding the approximation of the driving behaviors of (C)AVs (especially CF behavior) with many state‐of‐the‐art modelling methods. Still, there is no established CF model to mimic the accurate behavior of (C)AVs. Researchers often utilize existing mathematical CF models as well as limited data‐driven models for (C)AVs modelling. Meanwhile, several studies conduct simulation‐based impact assessments with various key performance indicators (KPIs). Identification of these KPIs is a crucial step for future studies. Hence, this paper presents a comprehensive outlook on different CF models with their adopted parameters for (C)AVs modelling and investigates how and in which aspects might the CF behaviors of (C)AVs are different from human‐driven vehicles. In addition, the recent publications in data‐driven CF models including their methodologies are explicitly discussed. This work also reviews simulation‐based studies with the reported impacts and used KPIs. Finally, in light of the findings of this paper, several future research needs are highlighted. [ABSTRACT FROM AUTHOR]

A flexible manufacturing system (FMS) due to its ability of being flexible in nature is concerned with automatic production of different parts in medium range. In short, it can be regarded as an automated manufacturing system. In this paper, an insight on previous work in the area of FMS modelling has been provided with an overview of research and development for better understanding of FMS. It serves as a medium for investigation of work that are accomplished by using different modelling techniques in FMS like mathematical, artificial intelligence, hierarchical, multi criteria decision-making method, Petri Nets and simulation. This paper will help researchers who are keen to do research in the area of FMS modelling, by highlighting contribution of available techniques in the field of FMS. It will also help them in deciding which modelling techniques can be used for a given problem. At last, comparison of different parameters considered in the recent papers of modelling FMS has been provided in the form of Table, along with a clear vision related to those works that still need to be investigated. [ABSTRACT FROM AUTHOR]

The article presents a study that determines the capabilities of the Earth System Model (ESM) used in climate modeling in general and computing applications. It outlines the method of the study that examines the different features of the system and its ability to communicate and regrid data. It also discusses the characteristics of the different approach of the system, as well as its future challenges that will arise from the increasing complexity of scientific problems.

The article discusses the experimental design and initial results relevant to the simulation of the mid-Pliocene warm period (MPWP) using MIROC, an atmosphere-ocean general circulation model (AOGCM). It relates that simulating MPWP is part of the Pliocene Model Intercomparison Project (PlioMIP). It identifies MPWP as the period in earth's history in which global increase in temperature had reached the predicted magnitude for the late 21st century duration.

Discusses the computational analysis of the Bayesian Paradigm. Determination of the traditional applied probability focus to call structural mathematics contrasts; Association of typical statistical focus on inferential mathematics; Terms of Bernouilli variables or perhaps multinomial variables; Increase in sophistication of probability models and the statistical interference.

Recently, Gutman et al., defined three vertex-degree-based topological invarients and obtained mathematical properties with their applications to physico-chemical properties of alkanes. In this paper, the expressions for the Reciprocal Randíc index, Reduced Zagreb index and Reduced reciprocal Randíc index of the generalized transformation graphs Gxy and their complement graphs are obtained. [ABSTRACT FROM AUTHOR]

Current physical systems are built in more that one coordinate: for example, electrical power systems, aeronautical systems and robotic systems can be modeled in multibond graphs (M B G) . However, in these systems, some elements use only one axis or dimension—for example, actuators and controllers—which can be modeled in bond graphs (B G) . Therefore, in this paper, modeling of systems in multibond graphs and bond graphs ( M B G - B G ) is presented. Likewise, the junction structure of systems represented by ( M B G - B G ) is introduced. From this structure, mathematical modeling in the state space is presented. Likewise, modeling of systems on a platform ( M B G - B G ) can be seen as symmetric to the mathematical model that represents these systems. Finally, a synchronous generator modeled by ( M B G - B G ) as a case study is developed, and simulation results using 20-Sim software are shown. Furthermore, an electrical power system connected to the power supply of a DC motor as another case study is explained. [ABSTRACT FROM AUTHOR]

In this paper, a light-controlled variable damping system (LCVDS) is proposed based on PLZT ceramics and electrorheological fluid (ERF). The mathematical models for the photovoltage of PLZT ceramics and the hydrodynamic model for the ERF are established, and the relationship between the pressure difference at both ends of the microchannel and the light intensity is deduced. Then, simulations are conducted by applying different light intensities in the LCVDS to analyze the pressure difference at both ends of the microchannel using COMSOL Multiphysics. The simulation results show that the pressure difference at both ends of the microchannel increases with the increase in light intensity, which is consistent with results from the mathematical model established in this paper. The error rate of the pressure difference at both ends of the microchannel is within 13.8% between the theoretical and simulation results. This investigation lays the foundation for the application of light-controlled variable damping in future engineering. [ABSTRACT FROM AUTHOR]

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This paper investigates the use of active aerodynamic surfaces (AASs) to enhance the ride comfort of sport vehicles. AASs are constituted by airfoils that are properly placed on the vehicle chassis, and whose angle of attack can be modulated at high frequency (10 Hz). Thus, AASs can be used to generate a lift force that helps in controlling the vertical acceleration of the sprung mass without negatively affecting the unsprung mass. Thanks to this property, AAS systems can overcome the tradeoff between comfort and road holding. In this paper, a control system is presented along with a detailed analysis of several design choices (controller bandwidth, surface size, and actuator requirements). Furthermore, the effect of several environmental factors is considered: 1) vehicle mass; 2) vehicle velocity; and 3) road roughness. A specific analysis shows that the proposed system can be integrated with classical semiactive suspension control algorithms. The system is validated on a complete vehicle model, showing improvements of the order of 30% in ride comfort with no negative effects on road holding. [ABSTRACT FROM PUBLISHER]

In middle and low voltage distribution networks, single-phase grounding fault is most like to occur, so the mathematical model to accurately reflect the characteristics of grounding arc is the basis of network fault analysis. Based on arc-gap balance theory, this paper analyzes the characteristics of the classic Mayr model and Cassie model, establishes an arc model with reasonable combination of Mayr and Cassie, and further studies the influence of arc length parameters on arc characteristics, and reflects the physical characteristics of the grounding arc. Finally, the arc model is simulated in a 10 kV distribution network in the fault form of intermittent arc grounding. By comparing the results with the actual situation, the correctness of the arc model is verified, which lays a good foundation for the following fault analysis of distribution network. [ABSTRACT FROM AUTHOR]

To analyse the behaviour of marine diesel engines in unsteady states for different purposes, for example to determine the fuel consumption or emissions level, to adjust the control strategy, to manage the maintenance, etc., a goal-based mathematical model that can be easily implemented for simulation is necessary. Such a model usually requires a wide range of operating data, measured on a test stand. This is a time-consuming process with high costs and the relevant data are not available publicly for a selected engine. The present paper delivers a rapid and relatively simple method for preparing a simulation model of a given marine diesel engine, based only on the widely available data in the project guides indicated for steady state conditions. After establishing the framework of the mathematical model, it describes how the parameters of the model can be adjusted for the simulation model and how the results can be verified as well. Conceptually, this is a trial and error method, but the presented case example makes clear how the parameters can be selected to reduce the number of trials and quickly determine the model parameters. The necessary descriptions are given through a case study, which is the MAN-B&W 8S65ME-C8 marine diesel engine. The engine is assumed to be connected to a constant pitch propeller. The presented mathematical model is a mean-value zero-dimensional type with seven state variables. The other variables of the engine are determined based on the state independent variables and the input value, which is the fuel rate. The paper can be used as a guideline to prepare a convenient mathematical model for simulation, with the minimum publicly available data. [ABSTRACT FROM AUTHOR]

There are few of transient control models are adapted to asynchronous induction coil launcher (AICL) with air core coil. Thus, many papers about AICL were written with the goal of increasing muzzle velocity of projectile. This paper concentrate on how to control the projectile speed and thrust accurately by using improved current filament (CF) method and variable voltage variable frequency (VVVF) scheme. The improved CF method contains mathematical model of three-phase inverter based on switch function, including conventional two level converter and cascaded multilevel converter models. The whole launch process is programmed with MATLAB. Simulation results show that this scheme have a smoother thrust fluctuation on projectile than other driving models. The motor parameters are changing with the temperature and frequency in launching process. Hence, the constant voltage frequency ratio (V/f) in this paper is more simple and reliable than vector control. To verify the control model and simulation results, a nine stages coil launcher prototype is constructed. The measured force and muzzle velocity are basically consistent with simulation results. It is proved that the improved CF method and VVVF strategy is feasible, and it is characterized by its small calculating amount that make it a valuable tool for design of AICL. The simple and excellent control of the thrust during launch process avoids load peaks, which means that the payload is handled more carefully compared to the classical launchers. [ABSTRACT FROM PUBLISHER]