Application Of Simulation Research Articles

Improving Students' Cognitive Understanding of Natural Selection Topics Through PhET Simulations

Natural selection is one of the topics of evolution material that is considered difficult for students, so it is necessary to have a practicum to help in understanding this material. Limited laboratory equipment in schools is an obstacle to learning evolution, so learning media are needed to support evolution learning. One of the learning media that can be applied is PhET simulation. PhET simulation supports evolution learning because it provides simulations in the form of processes of how living things experience natural selection mechanisms. This service program aims to describe students' cognitive understanding of the topic of natural selection with the help of the PhET simulation application. This activity is expected to be used as reference material for teachers who conduct practicums with the help of the PhET simulation application. The subjects who participated in this service activity were 30 students in class XII MIPA. The service activities were carried out on June 16–23, 2023, at SMAN 4 Tuban. The service activities carried out include training, discussion, and guidance. Based on the results of the program, it can be seen that the trainees were very enthusiastic about participating in the PhET simulation activities, the use of PhET simulation was easy to apply, and the trainees were easier to understand the material with the help of this application (87% of the time).

Застосування CAD/CAE-системи Solidworks у задачах аналізу міцності деталей верстатних пристосувань

The strength of parts is a critically important characteristic of the design of Clamping Fixtures. Calculating the strength of parts of Clamping Fixtures is necessary both when designing new structures and when checking existing ones. Traditional calculation methods, such as nominal stress calculation, although easy to use, have low accuracy. This creates a need for more accurate and efficient strength analysis methods. Modern CAD/CAE systems, in particular SolidWorks with the Simulation application, provide powerful tools for engineering calculations and finite element modeling. The algorithm of static calculation presented in the article on the example of the "Grip" part demonstrates the sequence of actions during strength analysis in the SolidWorks environment. This algorithm includes creation of a 3D model, generation of a finite-element mesh, material selection, determination of anchoring and loading conditions, calculation and analysis of results. An important stage of the analysis is the choice of the material of the part. At the same time, it should be taken into account that the databases of foreign CAD/CAE systems may not contain some domestic materials, which requires the selection of analogues with similar characteristics. The system allows you to visualize the results of calculations in the form of colored diagrams of stress and strain distribution. This greatly facilitates the analysis and interpretation of the results, allowing the critical areas of the structure to be quickly identified. The use of CAD/CAE systems for strength analysis of machine tool parts has a number of advantages compared to traditional methods. It increases the accuracy of calculations, reduces the time for their implementation, allows you to easily make changes to the design and instantly assess their impact on the strength of the part. The proposed method allows you to carry out both design and verification calculations of details of Clamping Fixtures. This makes it a versatile tool for structural engineers. The implementation of such strength analysis methods is particularly relevant both for the educational process and for real production. In terms of training, it allows students to gain practical skills in working with modern engineering systems. In production, it helps to improve the quality of design, reduce the number of errors and optimize structures.

Application Research of Virtual Simulation System From Complexity Perspective

The “Intelligent Manufacturing Technology and its Application” in higher vocational colleges has some problems such as limited practical training resources, high maintenance costs and security risks in the running process. Even if there is a simulation, it is a simple simulation. The repetitive imitation of traditional practical training links, and the virtual simulation teaching does not fully reflect the characteristics of virtuality, interactivity and spatiotemporality. Because of the existing problems in the training simulation development and application of the current curriculum, the development and application of the virtual simulation system under the complexity perspective is proposed. The results show that this application can improve the effectiveness of virtual system applications.

Assessment order and faking behavior

AbstractPersonality testing is a critical component of organizational assessment and selection processes. Despite nearly a century of research recognizing faking as a concern in personality assessment, the impact of order effects on faking has not been thoroughly examined. This study investigates whether the sequence of administering personality and cognitive ability measures affects the extent of faking. Previous research suggests administering personality measures early in the assessment process to mitigate adverse impact; however, models of faking behavior and signaling theory imply that test order could influence faking. In two simulated applicant laboratory studies (Study 1 N = 172, Study 2 N = 174), participants were randomly assigned to complete personality measures either before or after cognitive ability tests. Results indicate that participants who completed personality assessments first exhibited significantly higher levels of faking compared to those who took cognitive ability tests first. These findings suggest that the order of test administration influences faking, potentially due to the expenditure of cognitive resources during cognitive ability assessments. To enhance the integrity of selection procedures, administrators should consider the sequence of test administration to mitigate faking and improve the accuracy of personality assessments. This study also underscores the need for continued exploration of contextual factors influencing faking behavior. Future research should investigate the mechanisms driving these order effects and develop strategies to reduce faking in personality assessments.

The Effect Of Simulated Patient Education On Critical Thinking Trends In Medical School Students

Introduction &Objective: Critical thinking consists of mental processes such as reasoning, analysis, and evaluation. It is an objective super-thinking way open to self-correction and change. The main component of the current education methods is the acquisition of critical thinking. Simulated patient applications in medical education is an effective method that enables the student to acquire cognitive and psychomotor behaviors with active participation in the learning process. The aim of this study is to determine the change in the critical thinking tendencies of the third-year students of Akdeniz University Faculty of Medicine before and after simulated patient applications. Method: Third-year students of Akdeniz University Faculty of Medicine in the 2018-2019 academic year participated in the study. The students were asked to apply the Critical Thinking Disposition scale forms before the simulated patient applications. In the second stage of the study, the scale was reapplied to the students. The scale consists of 49 items. In our study, the results of the change between the first and the second applications of Critical Thinking Disposition scale were compared with the Paired Sample Test. Results &conclusion: A total of 345 students participated in the study. The mean score obtained from the Critical Thinking Disposition scale of the whole group was 191.63 (SD = 21.07) in the fall term and 193.69 (SD = 23.63) in the spring term. Although there was an increase in mean values of CTHD scale, the difference was not statistically significant (t(344)=-1.09, p = 0.277). The multidimensional nature of critical thinking skills and the need for continuity in order to keep this skill sharp are considered effective on this result. Different applications can be added to the training program to develop this skill.

Application of CFD Simulation to the Design of an Innovative Drying Chamber

Drying and sanitising equipment has been very common in industrial plants since the pandemic. These are devices that consume significant amounts of energy. The best solution is to use a drying chamber equipped with a heat pump, which allows partial recovery of the energy. In the design of the drying chamber, the drying time is important, which depends both on the parameters of the heat pump itself, and the geometry and airflow of the drying chamber. The geometry and airflow supply should be arranged to ensure a uniform distribution of velocity throughout the drying area. For this purpose, the use of CFD simulations has been proposed. A model was developed in ANSYS/FLUENT where all model parameters, including the optimal mesh density, turbulence models, etc., were determined. The model was verified on the experimental results of the basic design of the chamber. Then an innovative design was proposed that was modelled and optimised in terms of the distribution of the inlet’s perforation. The final design was made, and, at the same time, the simulation’s results were verified by measuring the velocity of airflow in the new design. Together with the optimisation of the heat pump, this made it possible to reduce the drying time by 50%, with a simultaneous reduction in the energy consumed.

A systematic approach for learning imbalanced data: enhancing zero-inflated models through boosting

In this paper, we propose systematic approaches for learning imbalanced data based on a two-regime process: regime 0, which generates excess zeros (majority class), and regime 1, which contributes to generating an outcome of one (minority class). The proposed model contains two latent equations: a split probit (logit) equation in the first stage and an ordinary probit (logit) equation in the second stage. Because boosting improves the accuracy of prediction versus using a single classifier, we combined a boosting strategy with the two-regime process. Thus, we developed the zero-inflated probit boost (ZIPBoost) and zero-inflated logit boost (ZILBoost) methods. We show that the weight functions of ZIPBoost have the desired properties for good predictive performance. Like AdaBoost, the weight functions upweight misclassified examples and downweight correctly classified examples. We show that the weight functions of ZILBoost have similar properties to those of LogitBoost. The algorithm will focus more on examples that are hard to classify in the next iteration, resulting in improved prediction accuracy. We provide the relative performance of ZIPBoost and ZILBoost, which rely on the excess kurtosis of the data distribution. Furthermore, we show the convergence and time complexity of our proposed methods. We demonstrate the performance of our proposed methods using a Monte Carlo simulation, mergers and acquisitions (M&A) data application, and imbalanced datasets from the Keel repository. The results of the experiments show that our proposed methods yield better prediction accuracy compared to other learning algorithms.

Seracam: characterisation of a new small field of view hybrid gamma camera for nuclear medicine

BackgroundPortable gamma cameras are being developed for nuclear medicine procedures such as thyroid scintigraphy. This article introduces Seracam® – a new technology that combines small field of view gamma imaging with optical imaging – and reports its performance and suitability for small organ imaging.MethodsThe count rate capability, uniformity, spatial resolution, and sensitivity for 99mTc are reported for four integrated pinhole collimators of nominal sizes of 1 mm, 2 mm, 3 mm and 5 mm. Characterisation methodology is based on NEMA guidelines, with some adjustments necessitated by camera design. Two diagnostic scenarios – thyroid scintigraphy and gastric emptying – are simulated using clinically relevant activities and geometries to investigate application-specific performance. A qualitative assessment of the potential benefits and disadvantages of Seracam is also provided.ResultsSeracam’s performance across the measured characteristics is appropriate for small field of view applications in nuclear medicine. At an imaging distance of 50 mm, corresponding to a field of view of 77.6 mm × 77.6 mm, spatial resolution ranged from 4.6 mm to 26 mm and sensitivity from 3.6 cps/MBq to 52.2 cps/MBq, depending on the collimator chosen. Results from the clinical simulations were particularly promising despite the challenging scenarios investigated. The optimal collimator choice was strongly application dependent, with gastric emptying relying on the higher sensitivity of the 5 mm pinhole whereas thyroid imaging benefitted from the enhanced spatial resolution of the 1 mm pinhole. Signal to noise ratio in images was improved by pixel binning. Seracam has lower measured sensitivity when compared to a traditional large field of view gamma camera, for the simulated applications this is balanced by advantages such as high spatial resolution, portability, ease of use and real time gamma-optical image fusion and display.ConclusionThe results show that Seracam has appropriate performance for small organ 99mTc imaging. The results also show that the performance of small field of view systems must be considered holistically and in clinically appropriate scenarios.

Numerical simulation application in occupational health studies: a review

Most occupational hazardous agents in workplaces should be evaluated and controlled. Different methods exist for identifying, evaluating and controlling these agents, such as numerical simulation tools. Numerical simulations can help experts to improve occupational health. Due to the importance and abilities of numerical simulations, this study divided occupational hazardous agents into 10 subgroups. These subgroups included air pollution, ventilation, respiratory airways, noise and vibration, lighting, radiation, ergonomics, fire and explosion, risk assessment and personal protective equipment. Recent research studies in each subgroup were then reviewed, and the codes and software used in simulations were determined. The results show that Fluent software and k–ϵ turbulence models are the most used in occupational health studies simulations. Today, different codes and software have been developed for simulation, and we suggest their use in occupational health studies.

Design and application of a radar target simulator

Abstract To fulfill the need for debugging boundary scenes in radar data processing development, this paper proposes a simulator design method for the editing and simulation of diverse combat scenes as required. The simulator was developed based on the VPX platform, including external control equipment, resource scheduling, beam control, target simulation, and data processing. The motion model is based on linear and circular models, the clutter model algorithm is the zero memory nonlinear transformation method based on K distributions, and the noise model is designed as Gaussian white noise, characterized by a probability distribution in the Gaussian distribution and a constant power spectrum. The generated plots are condensed, and their quality is calculated, for which the rate of plot rejection can reach more than 50% by controlling the feature elements. Finally, the simulated target trajectory is visually verified through Matlab.

A dynamic Pre-Darcy model and its application in the numerical simulation of enhanced geothermal system

Numerical simulations of Enhanced Geothermal Systems (EGS) currently primarily depend on the Darcy model, neglecting pre-Darcy flow in the matrix rock and the impact of temperature on pre-Darcy flow. This paper introduces a dynamic pre-Darcy model that accounts for the influence of temperature, deriving from the capillary flow model and boundary layer theory. This model is able to consider how temperature variations affect both the thickness of the boundary layer and the yield stress of the fluid. The reliability of the dynamic pre-Darcy model is validated through experimental data, and comparison with both static pre-Darcy and Darcy models demonstrates its superior ability to accurately capture the influence of temperature on pre-Darcy flow. Subsequently, a thermal-hydraulic simulation methodology incorporating the dynamic pre-Darcy model is developed to characterize mass and heat transfer between the matrix and fracture based on the framework of the embedded discrete fracture model (EDFM), which is further validated with analytical and numerical solutions. In the simulation of single-fracture case, we explore the impact of the dynamic pre-Darcy flow on mass and heat transfer between the matrix and fracture. Field-scale numerical simulations for EGS further demonstrate that the Darcy model tends to overestimate both production temperature and total extracted energy. In contrast, the static pre-Darcy model generally underestimates these metrics. The dynamic pre-Darcy model, however, provides more accurate and reasonable predictions.

Dimensionality and scales of preferential flow in soils of Shale Hills hillslope simulated using HYDRUS

AbstractPreferential flow (PF) processes are governed by subsurface soil structures at various scales. Still, model validation and mechanistic understanding of PF are very lacking. We hypothesize that PF at hillslope and larger scales cannot be described and quantified when neglecting small‐scaled spatially variable processes and simplifying the model dimensionality. The objective was to learn from comparing simulation results of multidimensional (1D, 2D, and 3D) and multiscale (pedon, catena, and catchment) modeling approaches with comprehensive datasets, and so as to evaluate PF simulations based on the Richards’ equation (solved by the HYDRUS software). Results showed limited alignment between 1D simulations and soil moisture data, mainly affected by vertical changes in porosity, permeability, and precipitation features. 2D and 3D simulations outperformed 1D models. 3D simulations provided satisfactory description of PF dynamics at the pedon scale, considering accurate representations of soil and bedrock structures for three dimensions (vertical, horizontal, and surrounding area). In 2D simulations at the pedon scale, models incorporating dual‐porosity and anisotropy of soils yielded more accurate predictions of water dynamics than single‐porosity and isotropic models. Furthermore, the application of 2D simulation at the catena scale identify PF pathways owing to the enhanced representation of the hydraulic connectivity between different locations along the slope. The results confirmed the significance of multidimensional and multiscale modeling approaches for PF simulations in hillslope hydrology. Considering the complexity and parameterization of 2D and 3D “bottom‐up” physically based models in representing spatial variability within and between soil profiles and/or underlying bedrock geology, the results contribute to creating a modeling framework applicable to identify the PF processes and thus their implications in managing water resources.

On application of molecular dynamics simulation for studying the effect of temperature and heating rate on HTL of biomass

Abstract Hydrothermal liquefaction (HTL) of biomass has garnered increasing attention as a promising pathway for converting solid biomass to liquid biofuels and valuable chemical products. HTL involves processing of biomass in water at high-temperature and high-pressure conditions. The heating rate during this process plays a critical role in determining the yield and composition of the liquefied products. To probe the impact of heating rate, we develop a detailed atomistic model biomass by using cellulose as model compound and place it in a simulated HTL reactor. Our Reactive molecular dynamics simulations are capable of capturing the dynamic chemical reactions and structural changes during HTL. The effect of reaction temperature and heating rates on reaction pathways, product distributions, and reaction kinetics is rigorously analyzed. Our findings reveal that the reaction temperature and heating rate significantly influences the extent of cellulose degradation and the composition of bio-oil product.

Enhanced direct and synthetic estimators for domain mean with simulation and applications

This article considers the issue of domain mean estimation utilizing bivariate auxiliary information based enhanced direct and synthetic logarithmic type estimators under simple random sampling (SRS). The expressions of mean square error (MSE) of the proposed estimators are provided to the 1st order approximation. The efficiency criteria are derived to exhibit the dominance of the proposed estimators. To exemplify the theoretical results, a simulation study is conducted on a hypothetically drawn trivariate normal population from R programming language. Some applications of the suggested methods are also provided by analyzing the actual data from the municipalities of Sweden and acreage of paddy crop in the Mohanlal Ganj tehsil of the Indian state of Uttar Pradesh. The findings of the simulation and real data application exhibit that the proposed direct and synthetic logarithmic estimators dominate the conventional direct and synthetic mean, ratio, and logarithmic estimators in terms of least MSE and highest percent relative efficiency.

A New Method for Traveling Wave Localization in Wide Area Power Grid Based on Trusted Zone Identification of Fault Lines

Abstract Aiming at the problem of dead zones in fault localization of wide area power grids, which makes it difficult to improve localization accuracy, a new method based on the trusted zone of fault lines for precise localization of wide area traveling waves is proposed. The algorithm is based on the principle of dual terminal positioning, which determines the fault line in the network through the action status of the circuit breaker, and determines the calculation area of network positioning based on the fault line, obtaining a set of dual terminal positioning calculation paths based on the fault line; Then, calculate the reliable localization zone of the faulty line under all dual end localization calculation paths and use it to determine whether the localization result of the path is reliable. For calculation paths with unreliable results, identify the second traveling wave of the fault point for calculation; Finally, all credible positioning results obtained are linearly fitted to obtain the final accurate positioning result. Simulation and practical application results have shown that this algorithm does not require finding the shortest path for traveling wave transmission, and can effectively improve the accuracy of wide area traveling wave positioning. It has high reliability, strong adaptability, and a positioning error of less than 100m.

Organoids in gastrointestinal diseases: from bench to clinic.

The etiology of gastrointestinal (GI) diseases is intricate and multifactorial, encompassing complex interactions between genetic predisposition and gut microbiota. The cell fate change, immune function regulation, and microenvironment composition in diseased tissues are governed by microorganisms and mutated genes either independently or through synergistic interactions. A comprehensive understanding of GI disease etiology is imperative for developing precise prevention and treatment strategies. However, the existing models used for studying the microenvironment in GI diseases-whether cancer cell lines or mouse models-exhibit significant limitations, which leads to the prosperity of organoids models. This review first describes the development history of organoids models, followed by a detailed demonstration of organoids application from bench to clinic. As for bench utilization, we present a layer-by-layer elucidation of organoid simulation on host-microbial interactions, as well as the application in molecular mechanism analysis. As for clinical adhibition, we provide a generalized interpretation of organoid application in GI disease simulation from inflammatory disorders to malignancy diseases, as well as in GI disease treatment including drug screening, immunotherapy, and microbial-targeting and screening treatment. This review draws a comprehensive and systematical depiction of organoids models, providing a novel insight into the utilization of organoids models from bench to clinic.

Stress tolerance in vitro, application in ice matrix and gastrointestinal simulation of Lactobacillus helveticus

Stress tolerance in vitro, application in ice matrix and gastrointestinal simulation of Lactobacillus helveticus

Simulation Application of BPNN-PID Controller with Improved Ant Colony Algorithm in Temperature Control System

Aiming at the nonlinear and hysteresis of PID controller in temperature control, this paper proposes a BPNN-PID control scheme with improved ant colony algorithm, and uses MATLAB to simulate and compare experiments. The results show that compared with the traditional ant colony algorithm control and BPNN control methods, the improved system has higher precision and better anti-interference ability in temperature control, and has higher practical application value.

Accurate model development for predicting sprinkler water distribution on undulating and mountainous terrain

The hilly terrain modifies the droplet landing positions in comparison to flat ground, complicating the prediction of sprinkler water distribution on such uneven regions. Utilizing a digital elevation model combined with droplet dynamics and evaporation models, droplet landing positions were calculated on both flat and uneven terrains. From the droplet landing positions and the corresponding water application rates on flat terrain, the water application rate on hilly terrains was deduced using the principle of water volume conservation. Subsequently, a software application was developed to assist in this prediction. Using the radial water distribution data from an individual sprinkler under various operating pressures and the elevation data of a hill, the software predicts the water distribution for either an individual sprinkler or an entire solid-set sprinkler irrigation system on the hill. This allows for the calculation of the average water application rate (h¯) and distribution uniformity (UCS) for combined sprinklers. The simulated water application rate on hilly terrains was validated using an experimental platform that replicates the sprinkler arrangement on a hill, devoid of plant canopy. Our findings indicate that the simulated water application rate for a sprinkler on hilly terrain aligns closely with the observed values, achieving a confidence coefficient (c) of 0.96. The developed software reliably predicts sprinkler water distribution on hilly terrains with significant accuracy for the conditions studied. We compared the UCS of the flat, hilly slope, and homogeneous slope terrains and found that the hilly slope better reflects the uneven water distribution owing to the undulating characteristics of the hilly terrain.

A method for quantitatively depicting the influence of vortices on the pressure forces acting on a hydrofoil in cavitating flow with tip clearance

In this paper, the force decomposition method (FDM) is proposed for decomposing the pressure forces acting on the immersed body. The major improvement in FDM is the applicability in RANS and LES simulations with non-constant density flows, e.g. cavitating flow. In the single-phase flow over a circular cylinder (Re = 3900), the FDM results show excellent agreement with the pressure force given by conventional method. In the cavitating flow over a hydrofoil with tip clearance, FDM can also reproduce the same tendency of the pressure force with an average deviation below 17%. In this case, the vorticity and kinematic effect induced force dominates the pressure force. In order to isolate the effect of attached cavitation near the suction side and tip clearance cavitation, a method combing domain cutting (manually) and cell extracting (by a threshold of vorticity magnitude) is proposed. The lift caused by vorticity force is mainly affected by the vortices shedding from the suction side of the hydrofoil. Also, the tip clearance region should not be ignored, where the lift generation by TLV is the interaction of strong shear and rotating flows.