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The creation of computational simulation experiments to inform modern biological research poses challenges to reproduce, annotate, archive, and share such experiments. Efforts such as SBML or CellML standardize the formal representation of computational models in various areas of biology. The Simulation Experiment Description Markup Language (SED-ML) describes what procedures the models are subjected to, and the details of those procedures. These standards, together with further COMBINE standards, describe models sufficiently well for the reproduction of simulation studies among users and software tools. The Simulation Experiment Description Markup Language (SED-ML) is an XML-based format that encodes, for a given simulation experiment, (i) which models to use; (ii) which modifications to apply to models before simulation; (iii) which simulation procedures to run on each model; (iv) how to post-process the data; and (v) how these results should be plotted and reported. SED-ML Level 1 Version 1 (L1V1) implemented support for the encoding of basic time course simulations. SED-ML L1V2 added support for more complex types of simulations, specifically repeated tasks and chained simulation procedures. SED-ML L1V3 extends L1V2 by means to describe which datasets and subsets thereof to use within a simulation experiment.

The study aims to improve the performance of the thermal power generation system in power plants by analyzing its working principle. The thermal power generation system of large power plants is taken as the research object. The Fluent software is used for simulation experiments. A new optimization method of the rotor structure in the electronic heat absorption equipment and heat exchange pipeline is proposed. By improving the rotor, the heat transfer efficiency of the heat exchange pipeline is greatly improved. Through the relevant research on the thermal power generation system, the rotor's heat transfer performance of the exchange tube is analyzed based on the strong heat transfer convection mechanism. Then the simulation experiment is carried out. Based on the heat transfer mechanism of the combined rotor in the tube path unit, the heat transfer pipe is optimized. The numerical simulation results of rotor heat transfer and fluid flow show that the average resource utilization rate increases with time. The average resource utilization efficiency of the system reaches more than 70% in 45 ms. When the pipe size is 100 mm, the performance of the resistance coefficient is 3.6 before improvement and 2.8 after improvement. When iteration times are 200, the rotor heat transfer of four kinds of pipes reaches the maximum, and the rotor heat transfer of No. 1 pipe with the size of 22 mm can reach 10000W. The research demonstrates the superiority of the proposed heat exchange tube, which provides a theoretical reference for optimizing the heat transfer tube and the efficiency of the thermal power generation system. [ABSTRACT FROM AUTHOR]

In this paper we focus our attention on the design of the feedback-based feed-forward controller asymptotically stabilizing the double-pendulum-type (D-P-T) crane system with the time-varying rope length in the desired end position of payload (the origin of the coordinate system). In principle, two cases are considered, in the first case, the sway angle of payload is uncontrolled and second case, when the sway angle of payload is controlled by an external force. Precise mathematical modeling in the framework of Lagrange formalism without the traditional neglect of the important structural parameters of the D-P-T crane system and numerical simulation in the Matlab environment indicate the substantial reduction of the transportation time to the desired end position. [ABSTRACT FROM AUTHOR]

Rainfall-induced shallow landslides are widely concerned for their sudden and group occurrences and serious threat to both lives and property. In this study, a hydraulic model coupling surface runoff and interstitial flow was established to study the failure characteristics of soil slopes under heavy rainfall. Based on the coupling of surface runoff and interstitial flow, we propose a modified failure mode for shallow soil slopes. In this mode, the safety factor of the shallow soil slope is derived, while the shear force acting on the slope from surface runoff is considered, as well as the resistance from the upper and lower edges of the sliding body. Compared with the classical infinite slope failure mode, the safety factor obtained by the method proposed herein is slightly larger. Additionally, the drag effect of runoff contributed positively to slope failure, and the safety factor decreased by approximately 7% while considering the drag force in slope stability analysis. Finally, theoretical analysis is verified by simulation experiments, and the results indicate good agreement between calculated and test values for failure shape and critical runoff depth. [ABSTRACT FROM AUTHOR]

Abstract STRIM (Statistical Test Rule Induction Method) has been proposed as a method to effectively induce if–then rules from the decision table, and its effectiveness has been confirmed by simulation experiments. The method was studied independently of the conventional rough sets methods. This paper summarizes the basic notion of the conventional rule induction methods and newly formulates the idea of STRIM, and then considers the relationship between STRIM and conventional methods, especially VPRS (Variable Precision Rough Set), and shows that STRIM develops the notion of VPRS into a statistical principle. In a simulation experiment, we also consider the condition that STRIM induces the true rules specified in advance. On the other hand, real-world datasets are often small and/or contain missing and contaminated values in the decision table from various reasons. In order to apply STRIM to real-world datasets, we examine the capacity of STRIM in such circumstances by a simulation experiment, after studying the question of what size dataset is required for STRIM. Such studies and examinations are very important to confirm if STRIM is properly applied to real-world datasets, and the results are reasonable. Graphical abstract Highlights • The rule induction by STRIM and the conventional Rough Sets, particularly, VPRS. • The relationships and differences between them. • The superiority of STRIM to the conventional methods at various points. [ABSTRACT FROM AUTHOR]

In this paper, based on the Back Propagation (BP) neural network algorithm, we introduce the idea of the Simulated Annealing (SA), and then propose a new neural network algorithm: Time Simulated Annealing-Back Propagation (TSA-BP) algorithm. The proposed algorithm can improve the convergence rate and numerical stability. By using this proposed algorithm, the learning rates and initial weights in the BP neural network could be easily adjusted. We show that the TSA-BP algorithm could reduce the errors caused by human-made factors. Several numerical experiments have been tested by using different disease data. Furthermore, we compared the TSA-BP algorithm to the other existing, well-known algorithms. Numerical results show higher accuracy and efficiency of the TSA-BP algorithm. [ABSTRACT FROM AUTHOR]

The problem of upward leader inception from transmission lines has not been thoroughly discussed, largely because of the difficulty to obtain experimental data under natural circumstances. Previous studies have primarily examined reduced-scale experiments or single-phase test lines. In this context, a real-size experimental system aimed at studying upward leader characteristics on both the phase conductor and ground wire is designed in this study. The results associated with real-size experiments corresponding to 110 kV, 220 kV, 500 kV and 1000 kV AC transmission lines, including the phase conductor and ground wire, are presented and discussed. It is shown that as the triggering voltage on the phase conductor increases, the streamer and leader incept earlier for a leader emerging from the phase conductor, and incept later for a leader emerging from the ground wire. The increase of the triggering phase angle corresponds to a higher voltage on the phase conductor, thereby increasing the strike probability on the phase conductor. The leader velocity and charge density present, in general, an increasing trend for the phase conductor as a function of the phase angle, while an opposite trend is observed for the leader emerging from the ground wire except for some special occasions. It is also determined that the phase conductor leader velocity is larger for a higher voltage class, while the charge density associated with the leader emerging from the phase conductor is smaller for a higher voltage class. [ABSTRACT FROM AUTHOR]

In order to improve the shielding effect of the transmission line, the accurate line system design is significant. The electrogeometric model and leader progression model are two typical and most widely used numerical analysis models to analyze the shielding failure performance. However, both models call for more experimental evidence for accurate application. This paper investigates the characteristics of an upward leader emerging from 110-, 220-, 500-, and 1000-kV single-phase conductors through simulated experiments, and the conductor parameters and heights adopted are similar to the actual transmission lines in operation. The ac voltage generator is connected to the conductor to apply an operating voltage to the conductor. The influence of bundle number and conductor height on the upward leader is also discussed in detail. The obtained characteristics of an upward leader will be helpful to build appropriate numerical analysis models for the shielding failure of the transmission line. [ABSTRACT FROM AUTHOR]

Random field models have been widely employed to develop a predictor of an expensive function based on observations from an experiment. The traditional framework for developing a predictor with random field models can fail due to the computational burden it requires. This problem is often seen in cases where the input of the expensive function is high dimensional. While many previous works have focused on developing an approximative predictor to resolve these issues, this article investigates a different solution mechanism. We demonstrate that when a general set of designs is employed, the resulting predictor is quick to compute and has reasonable accuracy. The fast computation of the predictor is made possible through an algorithm proposed by this work. This article also demonstrates methods to quickly evaluate the likelihood of the observations and describes some fast maximum likelihood estimates for unknown parameters of the random field. The computational savings can be several orders of magnitude when the input is located in a high-dimensional space. Beyond the fast computation of the predictor, existing research has demonstrated that a subset of these designs generate predictors that are asymptotically efficient. This work details some empirical comparisons to the more common space-filling designs that verify the designs are competitive in terms of resulting prediction accuracy. [ABSTRACT FROM AUTHOR]

A method of using the repeated impact machine to simulate the process of hard target penetration is proposed for the physical simulation experiment of hard target penetration fuze. The layer-count algorithm of hard target penetration fuze is introduced. The feasibility of simulating the penetration acceleration signal by use of the impact process is discussed. A simulation experimental system is designed, and a layer-count detonating experiment is done using a certain type of penetration fuze. The result is compared with shooting range test curve, proving the feasibility of the simulation experimental methods. The accuracy of fuze burst point control method can be comprehensively tested. The reliability of fuze moving parts can be testified. Further research is needed as the shock acceleration peak is low and the shock interval is long. [ABSTRACT FROM AUTHOR]

Multiple software programs are available for designing and running large scale system-level pharmacology models used in the drug development process. Depending on the problem, scientists may be forced to use several modeling tools that could increase model development time, IT costs and so on. Therefore, it is desirable to have a single platform that allows setting up and running large-scale simulations for the models that have been developed with different modeling tools. We developed a workflow and a software platform in which a model file is compiled into a self-contained executable that is no longer dependent on the software that was used to create the model. At the same time the full model specifics is preserved by presenting all model parameters as input parameters for the executable. This platform was implemented as a model agnostic, therapeutic area agnostic and web-based application with a database back-end that can be used to configure, manage and execute large-scale simulations for multiple models by multiple users. The user interface is designed to be easily configurable to reflect the specifics of the model and the user's particular needs and the back-end database has been implemented to store and manage all aspects of the systems, such as Models, Virtual Patients, User Interface Settings, and Results. The platform can be adapted and deployed on an existing cluster or cloud computing environment. Its use was demonstrated with a metabolic disease systems pharmacology model that simulates the effects of two antidiabetic drugs, metformin and fasiglifam, in type 2 diabetes mellitus patients. [ABSTRACT FROM AUTHOR]

Abstract: Numerical simulation can provide guidance to resolve injection production contradiction during the operation of underground gas storage, it is the key to ensure the smooth operation of underground gas storage. To perform accurate numerical simulation, accurate gas full-component analysis data is essential. In this study, the full-component experiment simulation of Ban-876 underground gas storage was done according to the laboratory experiment natural gas component analysis data. The saturation pressure calculation, phase diagram characteristics analysis, constant composition expansion experiment and constant volume depletion experiment were carried out with simulation methods. Finally, the full experimental data of initial condensate gas component was obtained which can provide reliable equation of state (EOS) parameters for the underground gas storage history matching and effect prediction. [Copyright &y& Elsevier]

To study the dissolution mechanisms of limestone driven by hydrodynamic reservoir pressure during different storage periods, a simulation experiment on the limestone in a hydropower station of Wujiang River in China was performed. Using a set of specially designed pressure corrosion equipment in an open system, the experiment simulated the dissolution process of limestone under hydrodynamic pressure (0-2.0 MPa) and temperature (15-85 °C). Results show that the amount of dissolution and its rate increase with hydrodynamic pressure and rising temperature, as a result the curve of dissolution rate is obviously changed. In addition, dissolution of carbonate rocks includes both chemical dissolution and physical damage. Differing from the situation under atmospheric pressure, with hydrodynamic pressure rise chemical dissolution, and physical damage increased synchronously ratios tending to be one-to-one. Results show that there is a coupling relationship between chemical dissolution and physical damage leading to a degree of more aggressive dissolution. Microscopic research based on scanning electron microscopy and a mercury injection test shows that the dissolution not only affects the surface of the rock, secondary pore, and mineral form, but also the inner pore structure, decreasing the permeability and connection among the structural planes of the rock. [ABSTRACT FROM AUTHOR]

In this paper, we have studied the dynamic evolution and output characteristics of soliton molecules in the passively mode-locked Yb-doped fiber laser through numerical simulation. Under two different intra-cavity average dispersion values (5.142 ps2/km, -4.461 ps2/km), with the increase of small signal gain (g 0) or gain saturation energy (E sat). Soliton molecules will not always maintain the state of two-soliton molecules or three-soliton molecules, but will occur at intervals. We have obtained specific multi-soliton molecules partitions, and studied the effects of g 0 and E sat on the pulse duration, peak power and pulse energy of soliton molecules in these regions. Simulation results have theoretical significance for the practical application of soliton communication. [ABSTRACT FROM AUTHOR]