Simulation Programming Research Articles

Simplified test program for hydrodynamic CFD simulations of wind-powered cargo ships

Four practical simplifications for modeling the hydrodynamic properties of a wind-powered cargo ship with CFD and a route simulation model is evaluated. We first test how much the drift-induced hull forces are dependent on Froude number, model scale, and heel angle. Then, we test the mathematical assumptions in the MMG maneuvering model, with particular focus on the rudder resistance as a function of drift angle, rudder angle and propeller thrust. The overall goal is to see if the hydrodynamics of the ship can be modeled with both a simplified CFD setup and a simplified route simulation model. For each tested simplification, we find that they can be used under specific conditions, but not always. We give specific recommendations based on our results. To improve the predicted rudder resistance from the MMG model, we suggest a slightly modified model based on classical lifting line theory. All the numerical experiments are performed using the open source CFD library OpenFOAM. The simulation setup is described, including details of the mesh design. The numerical uncertainty is quantified, and the simulations are compared against benchmark experiments.

The Correlation Between Digital Simulation Learning, Basic Programming, Mathematics and Students’ Knowledge: Optimizing Students’ Skill Program for Learning Results

The study aims to investigate students learning results of Mathematics, Digital Simulation, and Basic Programming subjects in Vocational High School 7 Takalar and to identify the correlation between students’ learning results on Mathematics and Digital Simulation Subjects and Basic Programming Subject. The research method was ex-post facto. The number of population was 210 and the samples were 63. Data were collected using documentation and test. Hypotheses were tested after performing Prerequisite Test. Results of the study show that: (1) students’ learning results in Mathematics were in the Good category. (2) students’ learning results in Digital Simulation were in the Good category. (3) students’ learning results in Basic Programming were in the Good category. (4) there is a strong correlation between students’ learning results in Mathematics and Basic Programming. (5) there is a strong correlation between students’ learning results in Digital Simulation and Basic Programming, (6) There is a Correlation between students’ learning results on Mathematics and Digital Simulation subjects and Basic Programming subject

Comparison of inviscid and viscid one-dimensional models of blood flow in arteries

The paper is devoted to the comparison of one-dimensional blood flow models in application to the solution of model problems. In the viscid case, the non-Newtonian properties of blood are considered. Original one-dimensional models, based on the Carreau, Carreau–Yasuda, Cross, and Powell–Eyring rheological models, are constructed by the averaging of the Navier–Stokes equations.The approach to the analytical solution of problems in the inviscid case is proposed. The originality of the method is based on the small perturbation of the initial rest state, corresponding to zero velocity. It leads to the solution of the linear wave equations. The solutions of three problems — for the infinite, semi-infinite, and finite intervals are obtained. The examples are presented for the small parameter value ∼10−2. Analytical solutions are used for the comparison of different one-dimensional models of blood flow, where the viscosity (Newtonian and non-Newtonian) is considered. The problems for the viscid models are solved numerically by the third-order WENO scheme. As the results of the comparison of models, the effects of the viscosity and velocity profile are analyzed.From a practical viewpoint, the solutions obtained by the perturbation method can be used for the testing of programs for numerical simulations and for the comparison of different blood flow models.

Temporal and genomic analysis of additive genetic variance in breeding programmes

Genetic variance is a central parameter in quantitative genetics and breeding. Assessing changes in genetic variance over time as well as the genome is therefore of high interest. Here, we extend a previously proposed framework for temporal analysis of genetic variance using the pedigree-based model, to a new framework for temporal and genomic analysis of genetic variance using marker-based models. To this end, we describe the theory of partitioning genetic variance into genic variance and within-chromosome and between-chromosome linkage-disequilibrium, and how to estimate these variance components from a marker-based model fitted to observed phenotype and marker data. The new framework involves three steps: (i) fitting a marker-based model to data, (ii) sampling realisations of marker effects from the fitted model and for each sample calculating realisations of genetic values and (iii) calculating the variance of sampled genetic values by time and genome partitions. Analysing time partitions indicates breeding programme sustainability, while analysing genome partitions indicates contributions from chromosomes and chromosome pairs and linkage-disequilibrium. We demonstrate the framework with a simulated breeding programme involving a complex trait. Results show good concordance between simulated and estimated variances, provided that the fitted model is capturing genetic complexity of a trait. We observe a reduction of genetic variance due to selection and drift changing allele frequencies, and due to selection inducing negative linkage-disequilibrium.

Development and evaluation of pilot simulated patient centre: Learning from the experience

Objectives: To compare the performance of paid actor-simulated patients: 1) before and after a simulated patient training programme aiming for programme enhancement; 2) to postgraduate/staff-simulated patients. Methods: Fifty-six student participants watched a series of video recordings of student pharmacist-paid actor-simulated patients role-playing and blindly assessed the performance of paid actor-simulated patients pre- and post-training using the Maastricht Assessment of Simulated Patients (MaSP). Seventy-three student participants compared the paid actor-simulated patients’ performance to postgraduate/staff-simulated patients. Data collected were analysed using paired t-tests and independent t-tests, respectively. Results: There was a statistically significant improvement in the collated MaSP scores for paid actor-simulated patients’ performance post-training in the authenticity of role-playing (mean score ± standard deviation (SD): 2.61 ± 0.30 (Pre-training); 2.70 ± 0.31 (Post-training), p < 0.05) but not the quality of feedback. Similarly, paid actor-simulated patients performed better (in the authenticity of role-playing but not the quality of feedback) when compared to postgraduate/staff-simulated patients. Conclusions: Paid actor-simulated patients require improvement in providing quality feedback to students to enhance students’ learning.

Research OF Complex Processes Based on Step-By-Step Modeling

Purpose. When solving practical problems that require the creation and further analysis of the model, an important criterion is the labour intensity of modeling. In this regard, the article is aimed at formalizing the modeling process and using the method of step-by-step modeling for the design of technological processes. This approach allows you to design processes and tasks according to the following stages: physical modeling, mathematical modeling, discrete computer modeling and simulation. Methodology. To solve the problem, a methodology of step-by-step modeling is used. The simulation involves 3 stages and uses the decomposition algorithm, i. e. considers the problem from global to detailed. At the first stage of this implementation, the necessary information is collected for the experiment. This information is presented in the form of statistics. In the second stage, further processing takes place, which is performed by checking the compliance of the input data and the process with the question of how this process should be performed. The last stage is the simulation of passages of this fragment, which is represented by a chain of transitions, obtaining statistics of time efficiency of this process, weaknesses of the process and the ability to compare the results obtained during modeling and in the real process, as well as the ability to predict future results and actions. Findings. The technique can be used to study complex technological processes in the enterprise. It allows modeling of complex processes to obtain information about the time efficiency of the technological operation, finding weaknesses in it and patterns in the occurrence of random events that may affect the operation. Using this approach can be very effective in the systems that require constant real-time monitoring, as this tool can be modified by adding sensor kits that will constantly send information to the system or equip an additional system that will provide ready-made information packets. Originality. The method of step-by-step modeling of representation has been improved, which consists in the simultaneous use of physical, mathematical and simulation modeling of complex processes with a set of stages of their implementation. Practical value. The proposed technique is designed for step-by-step modeling of the technological process with the subsequent construction of simulation programming.

Choice of the Fractal Method For Visualization of Input Data While Designing Support Systems for Decision-Making by Navigator

Introduction. The constant increase in the amount and intensity of traffic requires organization and precise management.Problem Statement. In the present-day conditions, when the number of vessels engaged on internal and external routes has been growing, without the vessel driver/navigator all alone are not physically able to assess the navigation situation and to make the right decision how to operate his vessel. The need to develop and to implement algorithms that help address the issue of navigation safety is an important task, especially when it comes to the management of groups of vessels. The main approaches that allow generalizing the information flows to ensure continuous and safe navigation are the formation of a structured system of processing and evaluation of input factors and related output parameters. This enables controlling the ergatic system of vessel, given a significant number of factors.Purpose. The purpose of this research is to create new approaches to controlling the vessel ergatic system for making an optimal and timely decision.Materials and Methods. Fractal methods for representation of the primary information and applied computer programs of mathematical simulation have been used.Results. The proposed model of information processing as part of the vessel ergatic system is designed to comp­rehensively ensure the safety of vessels, while providing control and optimization of both operational and organizational parameters and diagnostic functions, with the ability to predict and to prevent failures of the vessel engineering system.Conclusions. The applicability of general algorithms for the processing of information and its structuring according to the degree of impact has been shown. The application of these approaches solves the problem of overloading the navigator with excessive navigational information and reduces decision-making time. The developedalgorithm allows creating an automatic control system for groups of vessels in real conditions of difficult navigation environment.

751 Improving Engagement with Home-Based Surgical Skills Simulation

Abstract Introduction Surgical simulation has been repeatedly shown to facilitate technical skill acquisition. However, trainee engagement with self-directed practice remains variable, despite access to resources. Understanding the motivators and barriers to participation is crucial to develop modules which can effectively meet the learning needs of current, and future, surgical trainees. The aim of this qualitative study was to examine factors which influence trainee engagement with home-based surgical skills simulation. Method A series of one-to-one semi-structured interviews were conducted remotely with ST3 vascular trainees who had previously consented to take part in a national programme of home-based technical skills simulation. Interview data was transcribed and thematically analysed. Results 12 trainees were interviewed during a 4-week period. Overall, trainees valued simulation but found it difficult to balance against clinical commitments and mandatory training requirements, particularly if there were limited opportunities for skill transfer to the real-world environment. Although simulation was acknowledged to be a safe environment for experiential learning, trainees alluded to an underlying culture of perfection which limited willingness to learn from mistakes, even within a simulated setting. In addition, traditional attitudes about the apprenticeship model of surgical training prevail, with simulation often viewed as inferior to learning “on the job” in theatre. Conclusions Trainee engagement with home-based surgical skills simulation may be influenced by a range of systemic factors. In future, formal certification of simulation modules, mandating simulated competencies and curricular integration may help improve participation, as well as supporting cultural shift towards recognition of simulation as a vital component of modern surgical training.

Моделирование как способ реализации программы лабораторных работ в процессе преподавания технической защиты информации в дистанционном формате

The article discuses the issues of implementation of the program of laboratory works in the process of distant teaching the subject “Technical protection of information”. The necessity to use special equipment and special research methods in the course of a laboratory workshop in a full-time training is indicated. The actual approaches of organizing a laboratory workshop during distant and mixed learning for a number of typical engineering and technical subjects are analyzed. The use of programs for structural and functional modeling of electronic circuits in laboratory works during distant and mixed learning is rationalized. The article analyzes the functional features that exist in the known programs of circuit simulation, which are important from the point of view of the implementation of circuit modeling in the study of technical protection of information. As an example, the stages of performing the tasks of the laboratory work on the study of the properties of the 220 V mains power filter, suppressing high-frequency interference, are given. The stages of the methodology for interacting with trainees are given when using the Qucs application package with partial replacement of laboratory work with modeling.
 The problem of the research lies in the contradiction between the need to fulfill the requirements for a specialized laboratory workshop of the subject “Technical protection of information” for a number of technical specialties and objective difficulties or even impossibility of its full implementation in a traditional form during remote and mixed learning.
 The purpose of the study is to present an argument for implementation of circuit modeling programs to partially replace a laboratory workshop with work with specialized software tools that can be successfully used for training in a remote format with a minimum deployment time.
 Research methods - analysis of modern approaches to the implementation of laboratory workshop tasks in the world and in Russian and best practices of their application
 Conclusion: From the standpoint of cross-platform solution of import substitution, reduction of licensing costs, it is of interest to use the open source circuit modeling program Qucs in the teaching process. Some particular results obtained by the authors indicate the possibility of its application to study at least some topics of the subject “Technical information security”

Using multithreaded programming for reliability simulation of the restorable technical systems with identical elements and arbitrary reliability structure

This scientific paper deals with the real-time reliability simulation of the restorable technical systems with identical elements and arbitrary reliability structure using multithreaded programming for the Microsoft® Windows™ operating system. The offered by the author algorithms for simulation of each of the system elements and estimation of the stationary availability factor using the simulation results are discussed. The developed by the author software implementation of the offered algorithms for reliability simulation of technical systems is also presented. Finally, an example of reliability simulation of the technical system with identical elements and bridge reliability structure using the developed reliability simulation program is also given.

Modeling and Optimization of the Flocculation Process of Multi-Component Coal Waste Slurry Using Hybrid Polymer

ABSTRACT In the present study, the flocculation of multi-component coal waste slurry was investigated using an eco-friendly hybrid polymer naturally derived. The three significant operational parameters of the flocculation process, polymer dosage, suspension pH, and mixing time, were varied and the results were evaluated with the Central Composite Rotatable Design. In order to the flocculation process, mathematical model equations were derived by computer simulation programming applying the least-squares method using Minitab 15. Second-order response functions were produced for residual turbidity (RT), settleable solid speed (SSS), and settleable solid volume (SSV). The predictions were found to be in perfect agreement with the observed values (R2 values of between 0.82 and 0.86). The optimum results were obtained for the RT, SSS, and SSV as 3.59 NTU, 10 mm/min, and 143 ml, respectively, at polymer dosage – 350 ppm, suspension pH – 10, and mixing time – 1.0 min). Additionally, the predicted models have been presented as 3D (three-dimensional) response surface graphs to understand the results.

Parameter values for lot size and quality level via CAE simulation, statistical method, and mathematical programming

Because of the stochastic nature of production systems, it is necessary to first build an uncertainty model for subsequent real applications. Moreover, process parameter planning, quality design, and production inventory management are interdependent elements. In this research, a computer simulation model via computer-aided engineering (CAE) was developed to determine the optimal process parameters, lot size, and back order intervals for an integrated process design and inventory management system with simultaneous quality and cost considerations. Based on the estimated process time and costs obtained using CAE, the derived production rate and unit cost were then used for production inventory applications. In consideration of the uncertainty factor, the response surface method (RSM) was employed to analyze the output, namely the total costs incurred in employing the proposed approach, as well as the inputs, which include the cutting parameters, production quantity, and back order intervals. After the RSM was used to obtain the response functions, which represent the output of the collective interests, the mathematical programming (MP) was formulated based on the response functions to determine the optimal process parameters, process quality levels, production order quantities, and back order intervals. The total cost per set time unit was minimized by determining the required quality level, process parameter values, Economic Production Quantity (EPQ), and back order intervals. A cutting example was chosen to demonstrate the proposed approach. Two cases were used for comparison: the Integrated Case (the proposed approach herein) and the Disintegrated Case.

Design of Circular Microstrip Patch Antenna for WLAN Application

A roundabout microstrip fixes receiving wire is planned in this paper. The recommended receiving wire for remote neighborhood [WLAN] utilizes a 2.4GHz resounding recurrence. There are numerous different sorts of receiving wires, however, we'll zero in on roundabout radio wires, which are worked to support the resounding recurrence referenced previously. As a result of this recurrence determination, the radio wire is ideal for utilization in a remote Local Area Network [WLAN]. The High-Frequency Structure Simulator programming HFSS's optometric is used to make the proposed receiving wire more exact and proficient. Receiving wire plan enhancement is a term used to depict the way toward further developing the radio wire Model of a microstrip line. The HFSS programming was utilized to imitate the technique. This radio wire is made out of FR4 material, and the conditions for roundabout Patch configuration are presented and approved by all-around reproduced results. This radio wire has a 50-ohm input impedance and is based on an FR4 Epoxy dielectric substrate with a general permittivity of 4.4, a thickness of 1.60mm, and an overall permittivity of 4.4. The fundamental design and low profile characteristics of the recommended radio wire simplify it to deliver and are ideal for use in Wi-Fi organizations.

Behavioural insights (BI) for childhood development and effective public policies in Latin America: a survey and a randomised controlled trial

ObjectivesWe developed (a) a survey to investigate the knowledge of childhood health experts on public policies and behavioural insights (BI), as well as its use in Latin American and the...

A novel adaptive insertable cardiac monitor algorithm improves the detection of atrial fibrillation and atrial tachycardia in silico.

Insertable cardiac monitors (ICMs) provide a minimally invasive method of continuous monitoring for abnormal heart rhythms. While the benefits of ICMs are clear, current algorithm performance can be improved. The objective of this study is to assess the performance of a novel adaptive atrial fibrillation (AF) detection algorithm and separately programmable atrial tachycardia (AT) algorithm. A dual-stage detect-and-verify AF algorithm and separately programmable AT algorithm were developed. Sensitivity and PPV across a range of settings were determined in silico by comparison with an adjudicated Holter data set (n = 1966 with 229 patient days). Finally, the ability to improve performance through simulated remote programming was assessed. The dual-stage algorithm detected AF in all true AF patients (76/76) resulting in a patient-level sensitivity of 100%. Episode-level sensitivity and PPV ranged from 97.6% to 100% and 79.1% to 98.5%, respectively. Thirty-six false-positive episodes were observed and 32 (88.9%) of these were corrected with programming changes. Decoupling of AF and AT durations improved PPV from a range of 10%-22% to a range of 95%-100%. AF and AT algorithms were designed with novel features including an adaptive morphology assessment for AF detection and separately programmable durations for AT detection. In silico performance yielded improved PPVs while maintaining high sensitivity across a range of settings. Importantly, programming changes that may be made remotely with this system reduced false positives. These algorithms allow clinicians to individualize arrhythmia detection settings thereby improving data management and reducing clinic burden.

MODELING OF STEEL ELBOW MANUFACTURING PROCESSES VIA FINITE ELEMENT METHOD AND OPTIMIZATION OF PRODUCTION PARAMETERS

With the advancement of today's technologies, parts of pipe and elbow elements, natural gas pipelines, petrochemicals, machinery manufacturing industry, water distribution and flow systems, sewage systems, foundation piles, shipbuilding industry, nurse containers, aviation, space and defense industry, pipe networks, refineries , steel structures, tube and pipe engineering, etc. widely used in areas. In this study, extrusion method, which is one of the cold forming methods of elbow pipes, has been investigated. When the literature is examined, the production conditions of steel pipes and the problems that occur in production have been examined by different people and suggestions have been made. In this study, the production process of AISI 316L (EN 1.4404) quality stainless steel elbow pipes has been investigated. The mold design model created with the Solidworks program was transferred to the non-linear finite element analysis software ANSYS program for simulations. The process was modeled and simulated in the transient structural analysis section of the ANSYS program. In the process of transforming the pipe into an elbow product, we have learned about the stress distributions and obtaining the total deformation changes on the elbow. The parameters of the production process have been optimized by comparing the work done in the simulation and experimental data. In this way, cost-effective production is aimed by minimizing production costs. The data was extracted by simulating the production environment and conditions.

Development of a Performance Assessment Scale for Simulated Dispatcher-Assisted Cardiopulmonary Resuscitation (Telephone-CPR): A Multi-Center Randomized Simulation-Based Clinical Trial.

Dispatchers should be trained to interrogate bystanders with strict protocols to elicit information focused on recognizing cardiac arrest and should provide telephone cardiopulmonary resuscitation (CPR) instructions in all cases of suspected cardiac arrest. While an objective assessment of training outcomes is needed, there is no performance assessment scale for simulated dispatcher-assisted CPR. The aim of the study was to create a valid and reliable performance assessment scale for simulated dispatcher-assisted CPR. In this prospective, randomized, controlled, multi-centric simulation-based trial (registration number TCTR20210130002), the scale was developed according to the European Resuscitation Council (ERC) and American Heart Association (AHA) Guidelines 2015 and revised by experts. The performance of 48 dispatchers' telephone-CPR and of 48 bystanders carrying out CPR on a manikin was assessed by two independent evaluators using the scale and using a SkillReporter (PC) software to provide CPR objective performance. Continuous variables were described as mean (SD) and categorical variables as numbers and percentage (%). Comparative analysis between two groups used a Student t-test or a non-parametric test of Mann-Whitney. The internal structure of the scale was evaluated, including internal consistency using α Cronbach coefficient, and reproducibility using intraclass correlation coefficient (ICC) and linear correlation coefficient (R2) calculation. The scale included three different parts: two sections for dispatchers' (32 items) and bystanders' CPR performance (15 items) assessment, and a third part recording times. There was excellent internal consistency (α Cronbach coefficient = 0.77) and reproducibility (ICC = 0.93; R² = 0.86). For dispatchers' performance assessment, α Cronbach coefficient = 0.76; ICC = 0.91; R2 = 0.84. For bystanders' performance assessment, α Cronbach coefficient = 0.75; ICC = 0.93; R2 = 0.87. Reproducibility was excellent for nine items, good for 19 items, and moderate for 19 items. No item had poor reproducibility. There was no significant difference between dispatch doctors' and medical dispatch assistants' performances (33.0 [SD = 4.7] versus 32.3 [SD = 3.2] out of 52, respectively; P = .70) or between trained and untrained bystanders to follow the instructions (14.3 [SD = 2.0] versus 13.9 [SD = 1.8], respectively; P = .64). Objective performance (%) was significantly higher for trained bystanders than for untrained bystanders (67.4 [SD = 14.5] versus 50.6 [SD = 19.3], respectively; P = .03). The scale was valid and reliable to assess performance for simulated dispatcher-assisted CPR. To the authors' knowledge, no other valid performance tool currently exists. It could be used in simulated telephone-CPR training programs to improve performance.

Computer- Assessment of Attention and Memory Utilizing Ecologically Valid Distractions: A Scoping Review

Introduction: Deficits in the cognitive domains of attention and memory leave a large impact on everyday activities that are not easily captured in the clinical environment. Therefore, clinicians are compelled to utilize assessment tools that elicit everyday functioning that include real-world contexts and distractions. As a result, the use of computer-assisted assessment has emerged as a tool for capturing everyday functioning in a variety of environments. The purpose of this scoping review is to map how virtual reality, augmented reality, and computer-based programs have implemented distractions for clinical populations.Methods: A scoping review of peer reviewed publications was conducted by searching Pubmed, PsychInfo, Web of Science, Rehabdata, and Scopus databases (1960-October 20, 2020). Authors completed hand-searches for additional published and unpublished studies.Results: Of 616 titles screened, 23 articles met inclusion criteria to include in this review. Primary distraction display modalities included computer monitor displays (n = 12) and head mounted displays (HMD) (n = 7). While computer-assisted assessments included distractions, no systematic approach was utilized to implement them. Primary distractions included both auditory and visual stimuli that were relevant to the task and/or simulated environment. Additional distraction characteristics emerged including location, timing, and intensity that can contribute to overall noticeability.Conclusion: From this review, the authors examined the literature on the implementation of distractions in simulated programming. The authors make recommendations regarding identification, measurement, and programming with suggestions that future studies examining metrics of attention to implement distraction in measurable and meaningful ways. Further, the authors propose that distraction does not universally impact performance negatively but can also enhance performance for clinical populations (e.g. additional sensory stimuli to support focused attention).

Novel Approach to Groundwater Contaminant Transport Modelling

This paper comprehensively investigates literature about modelling techniques used in groundwater contaminant transport modelling. Modelling of groundwater is a useful way for the management of groundwater resources, also assessing the fate of contaminants and their remediation. Models very conveniently help to study complex real conditions and examine specific phenomena in addition to predicting the future behaviour of any problem. The use of groundwater simulation programming tools such as MODFLOW, MT3DMS, RT3D, FEFLOW, and MODPATH to model multi-directional contamination transport yields accurate results. Movement, storage, and change of solute concentration are largely regulated by groundwater flow gradient. As a result, a precise description of the flow mechanism is very important. If models are not properly constructed and interpreted, they can become complicated and may generate wide errors. Well-defined and clear modelling objectives produce suitable models for efficient error-free modelling processes. The study will assist modellers to clearly define their model objective and select appropriate modelling tools.

Express Delivery Handling Model Based on Monte Carlo Simulation and Linear Programming in the Background of Cloud Computing

This paper addresses the purchase options for courier companies looking for the type and number of machines to handle couriers, using Monte Carlo simulation and linear programming to simulate the processing of courier companies. The Jacques-Bella test for normality is first used, and the original hypothesis that both the machine processing capacity and the number of couriers given retain the random variables obey a normal distribution. The data are integrated into hourly time units using the principle of additivity of the normal distribution. Problem 1 requires the optimal number of equipment 1 to meet the basic operation demand of the courier company. According to the daily conditions, the article sets linear programming constraints, using Monte Carlo simulation of the number of machines working per hour for 200 cycles and gets the result that 16 machines are required. Problem 2 requires a comparison of the costs of purchasing equipment 2 and equipment 1. Due to the limitations of the work cycle of equipment 2, the article simulates 50 Google cycles to obtain the result that purchasing of three equipment 2 would meet the requirements. Because equipment 1 program costs less, the courier company should choose to buy 4 equipment 1.