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The utilization of carbon fiber-reinforced polymer/plastic (CFRP) components is primarily limited due to the lack of high-quality and least damage-based hole constructing technology. In this study, the delamination defect is investigated at the exit of CFRP drilling by a novel three-dimensional simulation model considering heat accumulation effect. The validity of the model is confirmed through experimental data of CFRP boreholes: surface temperature distribution at the borehole outlet, drilling axial force, and delamination factor at the outlet. The model exhibited high accuracy in theoretical analysis of CFRP 3D drilling with/without temperature. Additionally, the variation in temperature field and corresponding delamination damage is analyzed through simulation of CFRP drilling process at the exit plane of a hole. Results indicate that delamination damage occurs during unsupported dry drilling when half of the length of the main cutting edge impale the workpiece after reaching its exit plane. The changes in axial force caused delamination under different processing parameters, and a quantitative relationship is established through multiple regression analysis. The appropriate processing parameters can effectively reduce delamination during CFRP drilling. Specifically, accurate measures can ensure sufficient heat conduction and minimize heat accumulation during the formation stages of exit-related delamination. [ABSTRACT FROM AUTHOR]

Introduction: Chemical mass casualty incidents (MCIs) pose a substantial threat to public health and safety, with the capacity to overwhelm healthcare infrastructure and create societal disorder. Computer simulation systems are becoming an established mechanism to validate these plans due to their versatility, cost-effectiveness and lower susceptibility to ethical problems. Methods: We created a computer simulation model of an urban subway sarin attack analogous to the 1995 Tokyo sarin incident. We created and combined evacuation, dispersion and victim models with the SIMEDIS computer simulator. We analyzed the effect of several possible approaches such as evacuation policy ('Scoop and Run' vs. 'Stay and Play'), three strategies (on-site decontamination and stabilization, off-site decontamination and stabilization, and on-site stabilization with off-site decontamination), preliminary triage, victim distribution methods, transport supervision skill level, and the effect of search and rescue capacity. Results: Only evacuation policy, strategy and preliminary triage show significant effects on mortality. The total average mortality ranges from 14.7 deaths in the combination of off-site decontamination and Scoop and Run policy with pretriage, to 24 in the combination of onsite decontamination with the Stay and Play and no pretriage. Conclusion: Our findings suggest that in a simulated urban chemical MCI, a Stay and Play approach with on-site decontamination will lead to worse outcomes than a Scoop and Run approach with hospital-based decontamination. Quick transport of victims in combination with on-site antidote administration has the potential to save the most lives, due to faster hospital arrival for definitive care. [ABSTRACT FROM AUTHOR]

With global economic integration and rapid IT advancements, enterprises face complex market environments and intense competition. Efficient management and coordination of supply chains and manufacturing are critical. This study explores optimization strategies for integrated supply chain and manufacturing management using system dynamics. Initially, it investigates the contractual collaboration model based on system dynamics, analysing dynamic behaviours and optimization strategies. Subsequently, a system dynamics simulation model of the integrated system is constructed. Simulation analysis reveals the interactive relationships and dynamic patterns within the system. While many studies focus on static analysis, they often overlook dynamic changes and complex interactions. This study enriches the theoretical framework and provides solutions for enhancing management efficiency and competitiveness in a volatile market. [ABSTRACT FROM AUTHOR]

The list of standard abbreviations for JDS is available at adsa.org/jds-abbreviations-24. Nonstandard abbreviations are available in the Notes. An increasing number of countries are investigating options to stop the spread of the emerging zoonotic infection Salmonella Dublin (S. Dublin), which mainly spreads among bovines and with cattle manure. Detailed surveillance and cattle movement data from an 11-yr period in Denmark provided an opportunity to gain new knowledge for mitigation options through a combined social network and simulation modeling approach. The analysis revealed similar network trends for noninfected and infected cattle farms despite stringent cattle movement restrictions imposed on infected farms in the national control program. The strongest predictive factor for farms becoming infected was their cattle movement activities in the previous month, with twice the effect of local transmission. The simulation model indicated an endemic S. Dublin occurrence, with peaks in outbreak probabilities and sizes around observed cattle movement activities. Therefore, pre- and postmovement measures within a 1-mo time window may help reduce S. Dublin spread. [ABSTRACT FROM AUTHOR]

In order to improve the measurement accuracy of mutual inductance parameters of transmission lines in the environment of double circuit power lines without power outage, this paper establishes simulation models for measuring mutual inductance parameters of transmission lines using the different frequency method in two modes: equal and unequal zero sequence self‐parameters of two circuit lines, using a parallel zero sequence coupling model of double circuit power lines. In the article, simulation analysis is conducted on the line parameters with a coupling coefficient between 0.4 and 0.6 and a line length of 20–50 km. In order to further verify the correctness of the simulation model and measurement methods, a test bench was established based on the principle of line mutual inductance parameter testing in a laboratory dual circuit line without a power outage environment for experimental testing. By comparing the test values under experimental conditions with the standard values, it has been proven that the model and method can meet the actual measurement requirements of engineering. [ABSTRACT FROM AUTHOR]

CO2 laser machining is a cost effective and time saving solution for fabricating microchannels on polymethylmethacrylate (PMMA). Due to the lack of research on the incubation effect and ablation behavior of PMMA under high-power laser irradiation, predictions of the microchannel profile are limited. In this study, the ablation process and mechanism of a continuous CO2 laser machining process on microchannel production in PMMA in single-pass and multi-pass laser scan modes are investigated. It is found that a higher laser energy density of a single pass causes a lower ablation threshold. The ablated surface can be divided into three regions: the ablation zone, the incubation zone, and the virgin zone. The PMMA ablation process is mainly attributed to the thermal decomposition reactions and the splashing of molten polymer. The depth, width, aspect ratio, volume ablation rate, and mass ablation rate of the channel increase as the laser scanning speed decreases and the number of laser scans increases. The differences in ablation results obtained under the same total laser energy density using different scan modes are attributed to the incubation effect, which is caused by the thermal deposition of laser energy in the polymer. Finally, an optimized simulation model that is used to solve the problem of a channel width greater than spot diameter is proposed. The error percentage between the experimental and simulation results varies from 0.44% to 5.9%. [ABSTRACT FROM AUTHOR]

With recent outbreaks of foot‐and‐mouth disease (FMD) in Indonesia and Bali, industry, government and public concern for its incursion into Australia is increasing. The potential impact of an outbreak on the agricultural industry and national economy could be devastating. To date, research conducted in relation to FMD in Australia predominantly concerns simulations and models performed to predict various outcomes. This project critically appraises the current literature regarding the simulated use of vaccination and its effectiveness for controlling the spread of FMD in Australia in the event of an outbreak. Findings from 10 modelling studies suggest that vaccination is effective at controlling the size and duration of an outbreak (under certain conditions), however, there is less clarity about cost‐effectiveness. [ABSTRACT FROM AUTHOR]

Current research on overvoltage in trains can be divided into field tests and circuit simulations. The circuit simulation study focuses on the overvoltage amplitude distribution, the oscillation frequency of the main operating overvoltage is also an important characteristic, and the amplitude and frequency characteristics of the overvoltage need to be considered in the study of its suppression method. However, there is currently limited research on the frequency distribution of overvoltage. To provide guidance for the study of overvoltage suppression in the operation of the main circuit breaker, a new simulation model of train operating main break overvoltage is proposed based on the three-dimensional structure of the car body, high-voltage cables and rails. The model is used to simulate the transient overvoltage characteristics of the high-voltage cable core and each car body during the operation of the main circuit breaker, and the distribution of the overvoltage in each car body is obtained. The simulation results show that the maximum overvoltage amplitude during the operation of car 1 is 6.10 kV, while it is the smallest for car 4. The overvoltage amplitudes of cars 1 to 4 are all above 1 kV, and it was found that there are two main oscillation frequencies of the main overvoltage during the operation of the car body, which are 0.70 MHz and 1.30 MHz. Furthermore, the accuracy of the distribution characteristics and spectral characteristics of the train operating main break overvoltage is verified by static tests on the existing trains, and the test data show that the simulation results are extremely accurate in terms of overvoltage amplitude distribution, and the error between simulation and test does not exceed 5% in terms of amplitude, except for car 4. In terms of spectral characteristics, both simulation and experiment have two main oscillation frequencies, which can be considered consistent between simulation and experiment. Therefore, it can be concluded that the simulation model based on the three-dimensional structure has the ability to simulate the characteristics of operating overvoltage with high accuracy and provides guidance for overvoltage suppression research. [ABSTRACT FROM AUTHOR]

Rationale: Reducing the risk of exacerbation is a fundamental goal in managing stable chronic obstructive pulmonary disease (COPD). Guidelines recommend triple therapy (inhaled corticosteroids, long-acting muscarinic antagonists, and long-acting β-agonists) only as a stepup from dual therapy (long-acting muscarinic antagonists and long-acting β-agonists) for patients at continued high risk of exacerbation, because of the trade-off of an increased risk of pneumonia associated with inhaled corticosteroid–containing therapies. However, there is little evidence on the optimum timing of initiating triple therapy. Objectives: To perform a benefit–harm analysis to evaluate the net benefit of earlier initiation of triple therapy for the prevention of acute exacerbations in patients with COPD compared with standard timing recommended in current guidelines. Methods: We used a validated whole-disease microsimulation model of COPD in the Canadian general population aged ⩾40 years to determine the benefit versus harm of earlier initiation of triple therapy over a 20-year time horizon compared with standard care. We assessed net change in quality-adjusted life-years (QALYs) from the reduction in risk of acute exacerbations and the increased risk of treatment-related pneumonia in subgroups of patients with COPD defined by exacerbation history, symptoms, and disease severity. Model parameters were determined from clinical trials and other published literature. Key parameters were varied in one-way sensitivity analysis. Results: In patients at high risk of acute exacerbation (54.7% female; mean age, 74.0 yr; 68% Global Initiative for Chronic Obstructive Lung Disease grades I and II), earlier initiation of triple therapy was associated with a net QALY gain of 4.8 per 100 patients with COPD over 20 years compared with standard care. The net QALY gain increased to 5.9 per 100 patients in the subgroup of patients with a high symptom burden (modified Medical Research Council dyspnea scale score, >1). Earlier initiation remained net beneficial in all subgroup and sensitivity analysis scenarios. Conclusions: Modeling suggests that earlier initiation of triple therapy is likely to be net beneficial for patients at high risk of acute exacerbation, with an even greater benefit to patients with a high symptom burden. Further clinical research is needed to verify these findings in empirical studies. [ABSTRACT FROM AUTHOR]

Context: The number of publications that evaluate or use landscape connectivity has grown dramatically in recent years. But the biological realism of common connectivity assessments remains limited. To address this shortcoming, I introduce a flexible methodology for evaluating functional landscape connectivity that can be quick to implement, biologically nuanced, and straightforward to interpret. Methods: I combined a US Fish and Wildlife Service land cover map with information from existing empirical studies to develop a movement simulator for the Fender's blue butterfly, an endangered species in Oregon, USA. I use the resulting butterfly model to explore the concepts and mechanics behind my novel connectivity assessment methodology. Results: My methods are able to identify clusters of connected resource patches, quantify and visualize movement rates between patches, and identify opportunities for enhancing connectivity through restoration and mitigation. My results include an emergent dispersal kernel that captures the influence of movement behavior on connectivity. Discussion: The methods I introduce are capable of generating detailed yet practical connectivity analyses that can incorporate considerable biological and behavioral realism. My approach is simple to implement, and the requisite data can be modest. The toolkit I developed has the potential to standardize connectivity assessments that use either real or simulated movement data. [ABSTRACT FROM AUTHOR]

Purpose: To study the published literature for various models used for simulation and training in the field of pediatric colorectal surgery. Method: A PubMed search was conducted for studies of simulation models in anorectal malformation on 24 March 2024 with the search words 'simulation pediatric colorectal surgery' followed by another search on 'simulation AND anorectal malformation' that gave 22 and 14 results, respectively (total 36). After removing 4 duplicate publications, 12 were found relevant to simulation and training in colorectal diseases. One publication relevant to the topic was added from literature, thirteen articles were studied. Results: Of these, 5; 1; 4; and 3 were on inanimate models; animate model; 3D reconstructions; and training, respectively. Simulation models are available for posterior sagittal anorectoplasty. The same inanimate model was used in five articles. The animate model was based on a chicken cadaver. 3D models have been made for personalized preoperative assessment and to understand the imaging in anorectal malformation. One 3D model was made by regeneration of organoid epithelium. Training modules were made to evaluate surgical dissection, standardize surgical techniques, and improve proficiency. Conclusion: Simulation models are an important tool for teaching the steps of surgery and discussing the nuances of operative complications among mentors and peers. With advances in this field, the development of high-fidelity models, more training modules, and consensus on surgical techniques will benefit surgical training. [ABSTRACT FROM AUTHOR]

This study investigated the economic performance of pastoralist small ruminant flocks in Kajiado county, Kenya, and the financial impact of mortalities and changes in performance indicators. A survey of 129 pastoralist small ruminant flocks captured production and economic data for a 12-month period via interview. Simulation models were then developed for flocks with different performance levels and trading activities. Their gross margins, and the financial impact from mortalities, were estimated. Sensitivity analyses were conducted for select performance indicators to assess their relative economic importance. On average, pastoralists who were not purchasing supplementary feed (79% of flocks) had gross margins of KSh 3,016 - KSh 3,123 per reproductive female. Goat production generated 2.43-2.51 times greater returns than sheep production. High efficiency mixed flocks achieved 2.04-2.06 times greater returns than medium efficiency flocks, and 12.19-14.25 times greater returns than low efficiency flocks. Pastoralist-only flocks had 3.82-4.01 times greater returns than pastoralist-traders. Financial losses due to mortality were on average 17.81% of the starting flock value. Fecundity and abortion rates in sheep, and parturition rate in goats, had the greatest economic impact. The developed models could support decision-making toward improving the economic performance of pastoralist flocks and the evaluation of interventions and external shocks. [ABSTRACT FROM AUTHOR]

This experiment was designed to study the surface defects of 20 % volume fraction SiCp/Al composites after grinding and to provide the necessary experimental results for optimizing grinding parameters. Based on the two-dimensional cutting simulation model of single particle, the main damage of particles in matrix during machining has been investigated. The particles in SiCp/Al composites are randomly distributed and the tool will cut through multiple particles in a single cut and at different locations. A single particle cutting model was developed to study the different states of particle fragmentation by cutting through the upper, middle and lower parts of the particles respectively. Nine groups of parameters were obtained by orthogonal experimental design, and electroplated diamond grinding rod was used as the grinding tool for grinding experiment. In order to get the best surface grinding parameters, a ternary linear regression equation was selected to be established. Significance test could prove the reliability of the linear regression equation, and then, the optimal solution of this equation can be calculated by the MATLAB genetic algorithm toolbox. From the simulation and experimental results, it can be seen that the stress begins to concentrate when the cutting tool is close to the particle, and when the cutting stress exceeds the ultimate compressive strength, the particle is broken and part of it will be pulled out. The breakage of particles is not one-time, but requires many times of large cutting force to break the particles in sections, and the repeated breakage of particles eventually leads to the generation of overall cracks. [ABSTRACT FROM AUTHOR]

Proactive prevention and fighting fire at industrial facilities, often located in urbanized clusters, should include the use of modern methods for modeling danger zones that appear during the spread of the harmful combustion products of various chemicals. Simulation modeling is a method that allows predicting the parameters of a danger zone, taking into account a number of technological, landscape, and natural-climatic factors that have a certain variability. The purpose of this research is to develop a mathematical simulation model of the formation process of a danger zone during an emergency at an industrial facility, including an explosion of a container with chemicals and fire, with the spread of an aerosol and smoke cloud near residential areas. The subject of this study was the development of a simulation model of a danger zone of combustion gases and its graphical interpretation as a starting point for timely decision making on evacuation by an official. The mathematical model of the process of danger zone formation during an explosion and fire at an industrial facility presented in this article is based on the creation of a GSL library from data on the mass of explosion and combustion products, verification using the Wald test, and the use of algorithms for calculating the starting and ending points of the danger zone for various factor values' variables, constructing ellipses of the boundaries of the distribution of pollution spots. The developed model makes it possible to calculate the linear dimensions and area of the danger zone under optimistic and pessimistic scenarios, constructing a graphical diagram of the zones of toxic doses from the source of explosion and combustion. The results obtained from the modeling can serve as the basis for making quick decisions about evacuating residents from nearby areas. [ABSTRACT FROM AUTHOR]

Radio frequency energy harvesting RFEH technology has been applied widely in the development of wearable electronic power supply systems because of its eco-friendly and highly efficient characteristics. In the RFEH system the receiving antenna collects electromagnetic waves through electromagnetic coupling technology. Obviously the receiving antenna plays a crucial role in the energy harvesting efficiency of the RFEH system. Generally the antenna performance can be optimized by simulation and measurement. In the simulation of screen-printed fabric-based antenna for RFEH the establishment of a precise structure model of the substrate fabric is the basis for the simulation analysis. However in order to save the calculation cost most studies ignore the interwoven structural characteristics of the fabric in establishing a simulation model which leads to a big difference between the simulation and measurement results. To guide the actual product design and engineering application evaluation through the simulation of fabric-based antennas it is necessary to establish a fabric-based antenna model with high simulation accuracy and low calculation cost. To obtain the structural model of screen-printed woven fabric-based antenna for RFEH with high accuracy and low calculation cost this study constructed six different simplified structural models of filament woven fabrics firstly including interwoven meso-structure hole combining concave-convex structure hole structure plane concave-convex structure curved concave-convex structure and uniform structure. The interaction mechanism between the woven fabric and the electromagnetic wave was simulated. Based on this the antenna performance with different simulated structural substrates was analyzed parametrically with porosity and roughness as variables. And then several antennas with different simplified structural substrates were prepared to verify the feasibility of the simplified structural model of the substrate in the design of the antenna for RFEH. The results show that the interwoven meso-structure can be equivalent to a model with holes and / or a concave-convex structure model by comparing the reflectivity and transmittance. And the antenna radiation performance gain and efficiency with the uniform substrate structural model are significantly high. In addition the structure model with a rough surface has a more significant effect on the antenna performance than the non-rough surface structure model. Furthermore the model prediction and measured results of the antenna RFEH performance in the ultra-high frequency UHF range were compared. It is found that there is no significant difference between the two and there is no significant difference among different simplified structure models. The maximum transmission distance of the antenna reaches 220 cm and the received signal strength indication RSSI of unit area at 1 m distance exceeds 8. 442 mW/ cm². The output voltage and power conversion efficiency of the antenna are up to 135 mV and 60% respectively. Consequently in order to save the calculation cost the filament plain woven fabric substrate with a porosity of less than 30% and a roughness of less than 5. 39 μm can be equivalent to a uniform medium model in the simulation of screen-printed antenna for RFEH in the ultrahigh frequency range. An effective simulation method for woven fabric-based printed antenna for radio frequency energy harvesting in the ultra-high frequency range with high accuracy and low computational cost is provided by simplifying the fabric structure of holes and surface texture features. This method of model simplification has certain reference meanings for the model simplification of the antenna with complex structure applied to other fields. Furthermore this high-precision simulation model contributes to predicting the performance of the fabric-based antenna and optimizing the design of the fabric-based antenna so that fabric-based RFEH antennas can be applied to more extensive fields. [ABSTRACT FROM AUTHOR]

A current challenge of irrigationengineering is to modernize surface irrigation. For example, surge flow irrigation has the potential to increase the efficiency of applying irrigationwater. The objective of this study was to perform a sensitivity analysis using the performance indices: Application Efficiency (AE), Storage Efficiency (SE), Distribution Efficiency (DE), Deep Percolation (DP), and Runoff (RO), and to investigate their relationship with the main system variables: length (L), unit flow rate (Qo), surge cycles and surge time, using the SIRMOD model. The SIRMOD model simulates the hydraulics of surface irrigation at the field level. The model with the best fit of AE, DE, DP, and RO as a function of L, Qo, or surge cycles and surge time was a quadratic polynomial function with an R2 > 0.70. The model reflects the goodness of fit to the variable that is intended to be explained. The AE is an increasing function of L and a decreasing function of Qo, while DE and RO are decreasing functions of L and are increasing functions of Qo. The number of surges has an impact on the stream size of each surge and on the volume of water stored, but not on the performance indices. It was demonstrated that the SIRMOD model provided the ability to adjust the system parameters and design variables, giving answersto any surge flow configuration. The potential application efficiency (AEpot) (>80%) can be achieved by establishing, e.g., an optimal flow rate (Qopt), with a schedule for the cycle number and surge time, according to soil characteristics. [ABSTRACT FROM AUTHOR]

Objective: To compare the effectiveness of administering inferior alveolar nerve blocks (IANB) for the first time with or without a previous practical lesson using a simple manufactured simulator. Methods: This was a study designed to compare students' first administration of IANB anesthesia during 2022, with or without a previous practical lesson. Students were randomized into two groups. The experimental group attended both theoretical lessons and a practical lesson with a simulator device, while the control group attended only theoretical lessons. The theoretical lesson included usual contents such as anatomy, physiology, technical maneuvers for administering anesthesia, tips, and complications, and the practical lesson consisted of the administration of anesthesia using a simple manufactured simulator. After students applied their first IANB, its efficacy, and their answers to a questionnaire on a 5‐point Likert scale were recorded. Statistical analysis consisted of the Chi‐square test (p < 0.05). Results: The study recorded 60 anonymous surveys. The main difference observed was in instrument handing (p < 0.05), and there was a tendency in the ease of recognition of the anatomical marks used for the technique—pterygomandibular raphe and coronoid notch of the mandible (p = 0.08 and 0.11, respectively). No difference in success was observed (p > 0.05). Self‐confidence and personal feelings did not differ statistically. All students agreed strongly or partially that training with the simulator model was helpful. Conclusion: Students who used simple manufactured simulators achieved better outcomes for instrument handling, and possibly for identification of anatomical landmarks, than those who received only theoretical lessons. [ABSTRACT FROM AUTHOR]

Copyright of Cotton Textile Technology is the property of Cotton Textile Technology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ordnance Industry Automation is the property of Editorial Board for Ordnance Industry Automation and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The aim of this research is to devise a continuous simulation model for predicting ship crane failures to increase their reliability and reduce unplanned downtime during cargo loading and unloading operations. To predict the condition of the hydraulic system, a database from the GALIOT software package was used for carrying out maintenance on cranes at m/v "O" over a period of 120,000 working hours. In the research, fault tree analysis (FTA) was used to identify causal relationships between system failures and basic events, while the Markov mathematical model was used to model the system state and predict transitions between different failure states. A system dynamics simulation model was developed to simulate the behavior of a system using POWERSIM PowerSim Constructor 2.5.d (4002), and regression analysis was performed to analyze the simulation results and understand the relationships between dependent and independent variables. The results show that a model for predicting failures in the hydraulic motors and pumps of ship cranes was developed, and the Markov model makes it possible to estimate the frequency of transitions between states under the condition that the sum of reliability equals one. The simulation model shows high reliability of the cranes and a constant frequency of failures throughout the 120,000 operating hours, while the regression analysis confirms the validity of the simulation model and shows a strong correlation between the analyzed variables. These models are used to improve the planning of ship crane maintenance, reduce unplanned downtime, and predict and promptly detect failures, which overall minimizes maintenance costs and failures. [ABSTRACT FROM AUTHOR]

Eusocial Hymenoptera are often characterized by having facultatively or obligately sterile worker castes. However, findings across an increasing number of species are that some workers are non-natal-they have 'drifted' away from where they were born and raised. Moreover, drifters are often indistinguishable from natal workers in the work and benefits provided to joined groups. This seems an evolutionary paradox of providing benefits to potentially unrelated individuals over close kin. Rather than being mistakes, drifting is proposed to be adaptive if joiners either gain inclusive fitness by preferentially moving to other kin groups or through generalized reciprocity in which exchanging workers across groups raises group-level genetic diversity and creates social heterosis. It is unclear, however, if reciprocity is unlikely because of a susceptibility to cheating. In resolving this question, a series of evolutionary simulations show: (1) Reciprocity can persist under a range of genetic assumptions and scenarios of cheating, (2) cheating almost always evolves, but can be expressed in a variety of ways that are not always predictable, (3) the inclusive fitness hypothesis is equally or more susceptible to cheating. Moreover, existing data in Hymenoptera (although not extensive) are more consistent with generalized reciprocity. This supports a hypothesis that drifting, as a phenomenon, may more often reflect maximization of group and parental fitness rather than fitness gains for the individual drifters.

ABSTRACT: An increasing number of countries are investigating options to stop the spread of the emerging zoonotic infection Salmonella Dublin (S. Dublin), which mainly spreads among bovines and with cattle manure. Detailed surveillance and cattle movement data from an 11-yr period in Denmark provided an opportunity to gain new knowledge for mitigation options through a combined social network and simulation modeling approach. The analysis revealed similar network trends for noninfected and infected cattle farms despite stringent cattle movement restrictions imposed on infected farms in the national control program. The strongest predictive factor for farms becoming infected was their cattle movement activities in the previous month, with twice the effect of local transmission. The simulation model indicated an endemic S. Dublin occurrence, with peaks in outbreak probabilities and sizes around observed cattle movement activities. Therefore, pre- and postmovement measures within a 1-mo time window may help reduce S. Dublin spread.

Abstract In order to improve the measurement accuracy of mutual inductance parameters of transmission lines in the environment of double circuit power lines without power outage, this paper establishes simulation models for measuring mutual inductance parameters of transmission lines using the different frequency method in two modes: equal and unequal zero sequence self‐parameters of two circuit lines, using a parallel zero sequence coupling model of double circuit power lines. In the article, simulation analysis is conducted on the line parameters with a coupling coefficient between 0.4 and 0.6 and a line length of 20–50 km. In order to further verify the correctness of the simulation model and measurement methods, a test bench was established based on the principle of line mutual inductance parameter testing in a laboratory dual circuit line without a power outage environment for experimental testing. By comparing the test values under experimental conditions with the standard values, it has been proven that the model and method can meet the actual measurement requirements of engineering.

As the realization of carbon neutrality has been a main assignment for coping with the global climate change, it became necessary to analyze upcoming changes in electricity mix with economic and technical viewpoints. This paper presents a newly-developed simulation model that reflects the daily intermittency of renewable energy by applying daily average power supply-demand patterns for each season. Also, the paper provides an economic analysis in the viewpoint of investment cost, annual cost and power generation cost by utilizing the calculations from the simulation model. Four scenarios are selected for the analyses, one based on the Korean Government's 2050 Carbon Neutrality Scenario and three Nuclear Power Build-up scenarios, which are newly suggested by the authors. The simulation results show that the increase of nuclear energy from 5.7% of Government's Scenario to 37.7% of the proposed Nuclear Power Build-up Scenario leads to the decrease of about 704 billion US$ in investment cost and about 181 billion US$ in annual cost; with reduction in the increase of 2050 expected generation cost from 3.1 to 1.6 times compared with the referenced 2021 average cost. Further, this study has significance in performing the economic analysis with the expected daily power supply-demand patterns in 2050.

Introduction: Cost-effectiveness analyses typically ignore healthcare system resource constraints. Ophthalmology is affected by resource constraints because of increasing disease prevalence and the use of resource-intensive treatments. This study evaluated the impact of resource constraints on the cost-effectiveness of faricimab 6 mg, compared with aflibercept 2 mg and ranibizumab biosimilar 0.5 mg, for treating wet age-related macular degeneration (wAMD) or diabetic macular oedema (DMO) over a 5-year horizon. Methods: A microsimulation model estimated the impact of resource constraints on patients visits, delays, costs and quality-adjusted life-year (QALY) losses due to treatment delays at a typical UK National Health Service eye hospital treating 1500 patients with wAMD and 500 patients with DMO. Patient characteristics, treatment regimens and treatment intervals were informed using published literature and expert opinion. Resource constraint was represented by limiting the number of available intravitreal injection appointments per week, with growing demand caused by rising disease prevalence. The model compared outcomes across three scenarios; each scenario involved treating all patients with one of the three treatments. Results: Over 5 years, in a resource-constrained hospital, compared with aflibercept, faricimab use resulted in the avoidance of 12,596 delays, saved GBP/£15,108,609 in cost and avoided the loss of 60.06 QALYs. Compared with ranibizumab biosimilar, faricimab use resulted in the avoidance of 18,910 delays, incurred £2,069,088 extra cost and avoided the loss of 105.70 QALYs, resulting in an incremental cost-effectiveness ratio of £19,574/QALY. Conclusions: Accounting for resource constraints in health economic evaluation is crucial. Emerging therapies that are more durable and require less frequent clinic visits can reduce treatment delays, leading to improved QALY outcomes and reduced burden on healthcare systems. Faricimab reduced the number of delayed injections, leading to improved QALY outcomes for patients in a healthcare system with resource constraints. Faricimab is cost-saving when compared with aflibercept and cost-effective when compared with ranibizumab biosimilar. [ABSTRACT FROM AUTHOR]

One of the factors that lead to an increase in congestion on the road network is the growth of motorization levels in the city. Under such conditions, the number of private vehicles on city streets is increasing as delays at intersections and queues. As a result, the passage of the intersection is delayed, as drivers are forced to wait longer for their turn. When reconstructing a street or road, it is proposed to change the traffic management, the number of lanes and the configuration of some intersections to solve the problems described above. However, after the project is implemented, traffic flows are mostly redistributed, and the proposed changes may not be effective. It is imperative to conduct transport modeling, which allows checking the effectiveness of decisions and adjusting the project in the early stages, but not after implementation, to prevent the negative impact of such situations. When performing transport modeling, unnecessary investments that may arise after implementing the project can be avoided, or the feasibility of its implementation can be checked. The object of research is a section of the road network located in a settlement. It is worth noting that all approaches to intersections have high traffic volumes, which should be taken into account when creating project documentation. This article presents a design solution that includes reconfiguring the intersection, increasing the number of lanes, and conducting transport microscopic modeling of the existing and projected conditions to determine the effectiveness of changing the traffic management on the studied section of the road network. According to the results of the microscopic modeling, delays and queues on the approaches to the intersection have been reduced, which indicates that the decision was correct. PTV VISSIM software was used to perform transport modeling. After testing the simulation model and analyzing the results, it is possible to assess the impact of design decisions on the road network and, if necessary, make adjustments.

This paper presents an analysis of the acceleration of a fast boat using a simulation model. Mathematical equations of ship motion dynamics with two types of propeller capabilities are developed using MATLAB and Simulink as simulation tools. The equations are extended to include the acting thrust, resistance, propeller’s performance curves, and the PID governor curve for the acceleration manoeuvre. The application models the dynamic differential equations representing the vessel dynamics in one degree of freedom. MATLAB code was used to develop the ship acceleration as a multibody system. Modules of hydrodynamic forces, resistance, moments, and propeller performances were implemented to simulate the ship manoeuvring process. A comparison of the results for the boat’s propulsion performance with two different propellers and the characteristics of the PID governor, which controls the fuel dose in the gas turbines, was carried out. We present a summary including a comparative analysis of the results for the boat dynamics with and without the PID governor. The results obtained here confirm significant discrepancies between the results of numerical simulations with and without the PID governor.

Abstract Since conventional PID (Proportional–Integral–Derivative) controllers hardly control the robot to stabilize for constant force grinding under changing environmental conditions, it is necessary to add a compensation term to conventional PID controllers. An optimal parameter finding algorithm based on SAC (Soft-Actor-Critic) is proposed to solve the problem that the compensation term parameters are difficult to obtain, including training state action and normalization preprocessing, reward function design, and targeted deep neural network design. The algorithm is used to find the optimal controller compensation term parameters and applied to the PID controller to complete the compensation through the inverse kinematics of the robot to achieve constant force grinding control. To verify the algorithm's feasibility, a simulation model of a grinding robot with sensible force information is established, and the simulation results show that the controller trained with the algorithm can achieve constant force grinding of the robot. Finally, the robot constant force grinding experimental system platform is built for testing, which verifies the control effect of the optimal parameter finding algorithm on the robot constant force grinding and has specific environmental adaptability.