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The article explores the Soil and Water Assessment Tool (SWAT), its features, applications and advancements that propelled the use of this hydrological modelling tool. Topics discussed include runoff modelling using SWAT, sediment yield modelling, nutrient cycle modelling, and limitations such as the need for extensive input data, simulation of runoff and sediment in certain months, and performance depending on the specific characteristics of the watershed being studied.

Expert sport performers cope with a multitude of visual information to achieve precise skill goals under time stress and pressure. For example, a major league baseball or cricket batter must read opponent variations in actions and ball flight paths to strike the ball in less than a second. Crowded playing schedules and training load restrictions to minimise injury have limited opportunity for field-based practice in sports. As a result, many sports organisations are exploring the use of virtual reality (VR) simulators. Whilst VR synthetic experiences can allow greater control of visual stimuli, immersion to create presence in an environment, and interaction with stimuli, compared to traditional video simulation, the underpinning mechanisms of how experts use visual information for anticipation have not been properly incorporated into its content design. In themes, this opinion article briefly explains the mechanisms underpinning expert visual anticipation, as well as its learning and transfer, with a view that this knowledge can better inform VR simulator content design. In each theme, examples are discussed for improved content design of VR simulators taking into consideration its advantages and limitations relative to video simulation techniques. Whilst sport is used as the exemplar, the points discussed have implications for skill learning in other domains, such as military and law enforcement. It is hoped that our paper will stimulate improved content design of VR simulators for future research and skill enhancement across several domains. [ABSTRACT FROM AUTHOR]

Background: Providing authentic educational experiences in clinical teaching laboratories or health care simulation environments is fundamental to producing optimum learning. However, some simulated diagnostic devices are price prohibitive or yet to be developed. This article explores a collaborative effort between health academics and engineering interns to develop cost-effective, authentic devices that overcome limitations of those currently available. Method: Simulated patient tympanic thermometer and pulse oximetry devices were developed for use in clinical teaching laboratories and health care simulation environments. Results: The tympanic thermometers and pulse oximetry probes provide programmable temperature, pulse, and oxygen saturation for use with any commercially available manikins or standardized patients. Conclusion: Authentic simulated diagnostic devices can enhance reality and foster immersion in clinical simulation scenarios. Sharing cost-effective innovations designed to address the simulation-specific limitations of commercially available diagnostic devices provides health care educators with solutions that can enhance the authenticity of clinical teaching experiences for participants. [J Nurs Educ. 2021;60(4):235–239.] [ABSTRACT FROM AUTHOR]

The general instability in the environment of enterprises is the main reason for their quest for more and more reactivity, in order to adapt their products in time to market. The consequences of this are changes in products, processes, and the organization of companies. Development of the 'information system' within manufacturing departments makes the efficiency of methods to manage this system a critical point. Our aim here is to develop this efficiency, making possible integrated use of several modelling tools within a single project. We provide a classification of links that are possible between modelling tools. This classification is partially applied to links between IDEF0 and CIM-OSA. [ABSTRACT FROM AUTHOR]

Introduction: Beyond relevant cognitive tests, a simulated driving activity could be useful to observe performance and behaviour in a standardized 'driving-like' situation and provide information on attention, reaction time and information processing speed when evaluating the ability to continue driving after a brain injury or disease. The aim was to develop and evaluate concurrent validity and internal consistency of a computerized simulated driving task tool. Methods: Results from a new tool (CyberSiM, including three subtests and four result variables) were compared with results from the Trail Making Test, Useful Field of View test and Nordic Stroke Driver Screening Assessment. There were 126 healthy adults included in the study. Results: The correlation analysis showed significant correlations (p <0.001) for CyberSiM reaction time and all cognitive tests except for Useful Field of View 1. The CyberSiM showed good internal consistency, with Cronbach's alpha=0.85. Conclusion: The analysis of concurrent validity showed conformity to most cognitive tests. CyberSiM might be a useful complement to cognitive testing with the opportunity to observe some behaviours 'in a driving-like activity'. Further studies on clinical groups are needed to confirm its usefulness. [ABSTRACT FROM AUTHOR]

In order to research the repair control technology of the inclined shaft with soft surrounding rock, the inclined shaft soft roadway of one phosphate mine in Hubei is taken as an example to study the damage characteristics, the deformation mechanism of the surrounding rock and repair control technology of it. The X-ray diffraction was employed to analyze the mineral components of the surrounding rock, also the surrounding rock contains clay minerals, which are easy to swell when in contact with water. The roadway mainly presents the damage characteristics of roof subsidence, two side walls extrusion, U-steel arch set bend or break, etc. The whole section double arch synergy reinforcement technology method of “sprayed concrete + grouting + anchor bolt + anchor cable” is proposed. And the technical parameters of the repair scheme are determined by theoretical analysis, engineering analogy and engineering practice. The numerical simulation is adopted to verify the feasibility of the whole section double arch synergy reinforcement scheme. The application results show that the large deformation roadway can be effectively controlled by the combined support scheme, which can provide certain references significance for similar engineering. [ABSTRACT FROM AUTHOR]

This communication presents a cavity-backed slot antenna (CBSA) array for the estimation of direction of arrival (DOA). This new CBSA employs an alternative feeding structure to excite the radiation of cavity-backed slots and transfer the area for RF module implementation from the front surface of the array aperture to the bottom behind the cavity. This backfeeding design allows the accommodation of active RF modules inserted from the bottom behind the antenna aperture, and avoids interfering with the antenna radiation. The new feeding structure may also reduce the depth of the metal cavity and, in turn, decrease the thickness and weight of antennas in the phased array composition to make a compact array with a low profile. The bandwidth is found to be larger than that of a conventional CBSA. The antenna array for the DOA estimation has been prototyped with 32 elements. Experimental data and numerical simulation results are presented to validate the proposed antenna design concepts. [ABSTRACT FROM PUBLISHER]

Droplet microfluidics allows the implementation of several biochemical and bioanalytical protocols in microfluidic devices. However, this integration typically requires the use of microfluidic valves, which allow the control of different operations on the same channels network. Unfortunately, the valves commercially available are almost exclusively suitable for-single phase flow, and only one valve system compatible with multi-phase systems has been presented so far in the literature. We present here a new pinch-like valve that withstands high pressures (tested up to 4 bar), allows droplet manipulation and combines the advantages of conventional pinch valves regarding the absence of dead volume, while making negligible the backflow generated (less than 2 nL). The conception and design of the presented valve, based on numerical simulations, is performed by an optimized microfabrication strategy, combining PDMS soft-lithography and 3D printing technologies. The valves had been tested regarding their mechanical stability and proving their capability of allowing droplets passing through them, without any perturbation. Finally, the very small back-flow volume generated during the actuation, has been exploited for various applications in droplets microfluidics, like droplet handling, droplet-on-demand generation and sorting. [ABSTRACT FROM AUTHOR]

This paper focuses on analysis and modeling of complementary metal-oxide semiconductor (CMOS) resistive digital-to-analog converter (RDAC) potentiometers based on string digital-to-analog converter or Kelvin divider architecture. The model is developed by using very-high hardware description language (VHDL) analog and mixed-signal language, and accurately simulates basic static and dynamic parameters, integral nonlinearity, terminal voltage operating range, and leakage current at various operational modes for linear and nonlinear changing of the middle point (wiper). The model is implemented in the SystemVision simulation platform, using a style combining structural and behavioral elements. For verification of the model parameters are extracted for single-stage AD5235 and triple-stage AD5143 RDACs from analog devices as examples. The workability of the proposed models is validated by simulation and experimental testing of sample digitally controlled analog circuits. The comparative analysis shows that the achieved relative error, between the simulation and the experimental results at the maximum value of the nominal resistance equal to 25\,\rmk\Omega , is less than 5%. Moreover, an error of 5% is quite acceptable, considering the technological tolerances of the parameters. [ABSTRACT FROM PUBLISHER]

Multi-level and sequential computer experiments are commonly used to study complex systems in engineering and science. Suitable designs for such experiments require nested structures. Because a nested Latin hypercube design (NLHD) (Qian (2009)) can be constructed only when the run size in each larger design is a multiple of that in a smaller one, the use of NLHDs faces some limitations in practice. In this paper, we propose a random sampling procedure for constructing flexible NLHDs, which have no such a restriction. We also develop an efficient sequential algorithm to search for the optimal NLHDs with respect to some space-filling criteria. Simulation results show that our methods can yield flexible NLHDs with good space-filling properties. [ABSTRACT FROM AUTHOR]

The availability of digital X-ray detectors, together with advances in reconstruction algorithms, creates an opportunity for bringing 3D capabilities to conventional radiology systems. The downside is that reconstruction algorithms for non-standard acquisition protocols are generally based on iterative approaches that involve a high computational burden. The development of new flexible X-ray systems could benefit from computer simulations, which may enable performance to be checked before expensive real systems are implemented. The development of simulation/reconstruction algorithms in this context poses three main difficulties. First, the algorithms deal with large data volumes and are computationally expensive, thus leading to the need for hardware and software optimizations. Second, these optimizations are limited by the high flexibility required to explore new scanning geometries, including fully configurable positioning of source and detector elements. And third, the evolution of the various hardware setups increases the effort required for maintaining and adapting the implementations to current and future programming models. Previous works lack support for completely flexible geometries and/or compatibility with multiple programming models and platforms. In this paper, we present FUX-Sim, a novel X-ray simulation/reconstruction framework that was designed to be flexible and fast. Optimized implementation for different families of GPUs (CUDA and OpenCL) and multi-core CPUs was achieved thanks to a modularized approach based on a layered architecture and parallel implementation of the algorithms for both architectures. A detailed performance evaluation demonstrates that for different system configurations and hardware platforms, FUX-Sim maximizes performance with the CUDA programming model (5 times faster than other state-of-the-art implementations). Furthermore, the CPU and OpenCL programming models allow FUX-Sim to be executed over a wide range of hardware platforms. [ABSTRACT FROM AUTHOR]

The operational design and its practical application are directly influenced by the training, experiences of the individual command levels and as well they are determined by the economic development of the country. Its quality implementation in the practice is directly addicted upon operational art, which is the real output of the cognitive approach by commanders and staff, by air traffic control instructors and inspectors. And that's what it is sustained by their experience, cognition and as well as verdict -- to propose strategies and operations to set up and utilize armed forces. The usage of the simulation tool and synthetic environment is the core part to reach the aim of the high level of the efficiency and at the same time to reach the required level in the flight region safety. [ABSTRACT FROM AUTHOR]

The energy and environmental upgrading of the built sector is a burning topic that has urged scientific communities worldwide to keep searching for innovative high performance sustainable building products, systems, designs, and practices. The synergy among several approaches and methodologies has been widely accepted and established as the key in achieving the most sustainable constructions. The aim of this paper is to present a novel high performance building element that establishes a building's thermal comfort and effective cooling, while at the same time it has negligible energy requirements. The operation of this innovative solution is based on an active controlled temperature building shell that employs airflow patterns for the stabilization of the building's temperatures. This work investigates the energy performance of the controlled temperature building shell through the employment of numerical simulation tools, while life cycle methodology is also implemented for the assessment of the environmental impact of the novel element. The results and conclusions of the analysis will establish the overall level of performance of the proposed solution, and demonstrate the significance of integrating several methodologies for the promotion of the sustainable upgrading of the building sector. [ABSTRACT FROM AUTHOR]

A numerical model has been developed to estimate the shape of the liquid cone and the resulting jet in presence of external electric field. The model estimates the liquid velocity at the cone surface to calculate the electrical current. The equations of electric potential are solved numerically with an iterative procedure and then continuity and momentum equations solved in a commercial CFD code with electrical body forces. The model is validated by comparing with experimental results. [ABSTRACT FROM AUTHOR]

Purpose The purpose of this paper is to describe the evaluation of an educational occupational therapy home visit simulation newly built in Unity, compared with a previously created simulation based in the Open Sim platform. The evaluation is based on students’ preferences.Design/methodology/approach A simulation was built in Unity in which the academic content was identical to the previous Open Sim-based simulation. Student groups used the simulations then completed a questionnaire. Numerical data and descriptive comments were analysed.Findings Students preferred the simulation built in Unity to the Open Sim simulation. Improvements with the Unity simulation include; reduced time to gain competence to use, ease of use and fewer negative physiological experiences. The small percentage of students experiencing motion sickness is an ongoing concern and warrants further investigation. The Unity simulation may also be useful as an academic assessment tool.Research limitations/implications Findings are limited by short time usage of the simulations in 3D virtual worlds with confined spaces and no requirement for in-world group interaction, and by some methodological limitations including the research being based within a single higher education institution, and with a profession-specific group of students.Originality/value This paper highlights student preference for using a purpose built simulation created with Unity over a simulation built in Open Sim, showing where best to spend future development time and funding. Similar comparison research is scarce. [ABSTRACT FROM AUTHOR]

Medical procedures often involve the use of the tactile sense to manipulate organs or tissues by using special tools. Doctors require extensive preparation in order to perform them successfully; for example, research shows that a minimum of 750 operations are needed to acquire sufficient experience to perform medical procedures correctly. Haptic devices have become an important training alternative and they have been considered to improve medical training because they let users interact with virtual environments by adding the sense of touch to the simulation. Previous articles in the field state that haptic devices enhance the learning of surgeons compared to current training environments used in medical schools (corpses, animals, or synthetic skin and organs). Consequently, virtual environments use haptic devices to improve realism. The goal of this paper is to provide a state of the art review of recent medical simulators that use haptic devices. In particular we focus on stitching, palpation, dental procedures, endoscopy, laparoscopy, and orthopaedics. These simulators are reviewed and compared from the viewpoint of used technology, the number of degrees of freedom, degrees of force feedback, perceived realism, immersion, and feedback provided to the user. In the conclusion, several observations per area and suggestions for future work are provided. [ABSTRACT FROM AUTHOR]

Though several electronic assistive devices have been developed for the visually impaired in the past few decades, however, relatively few solutions have been devised to aid them in recognizing generic objects in their environment, particularly indoors. Nevertheless, research in this area is gaining momentum. Among the various technologies being utilized for this purpose, computer vision based solutions are emerging as one of the most promising options mainly due to their affordability and accessibility. This paper provides an overview of the various technologies that have been developed in recent years to assist the visually impaired in recognizing generic objects in an indoors environment with a focus on approaches based on computer vision. It aims to introduce researchers to the latest trends in this area as well as to serve as a resource for developers who wish to incorporate such solutions into their own work. [ABSTRACT FROM AUTHOR]

The flexion effect of a flexible wing during the hovering flight is systematically studied by using computer simulations when Reynolds number is kept at 140. The aerodynamic forces and flow vortex are investigated by solving the two-dimensional time-dependent incompressible Navier–Stokes equations using the finite volume method. The wing is modelled as a thin plate which has a rigid leading portion and a flexible aft part. The simulations are performed for a variation of the location of rotational centre and the amplitude of the flexion, and the corresponding changes of the aerodynamic forces and vortex shedding mechanism in the wake structure are investigated. Form the quantitative comparisons, the present simulations reveal that a moderate flexion during the hovering fly can provide a better performance for a flapping wing, while an excessive flexion will lead the aerodynamic performance become worse. Though the flexion does not change the force trace of the hovering wing, the magnitude of the instantaneous peak forces and mean periodic forces are definitely changed by the chordwise deformation. Compared with a rigid hovering wing, the dynamic flexion during hovering alters the intensity of the leading edge vorticity and the transfer direction of the wake. Here, the present results indicate that the aerodynamic forces can be altered by adding some deformation characteristics to the trailing edge of the wing. Furthermore, the appropriate flexion can be used to alter the aerodynamic performance of a wing and will be helpful for design and control of the flexible microflying vehicles. [ABSTRACT FROM AUTHOR]

This paper outlines the development and construction of an ontology necessary to accurately represent the concepts of a generic enterprise, primarily in a manufacturing context, for use with a discrete event simulation (DES) engine. Accuracy in this sense, means that the DES can be used as an operational and tactical decision making tool, and will be able to inform the end-user which decision is the optimal one (with respect to a set of key performance indicators), with a high degree of confidence. The ontology focuses on make-to-order and build-to-order enterprises, which operate a shop-floor arrangement, as opposed to an assembly-line system. The principal concepts dealt with in the ontology are orders, workflows and activities, resources, and calendars. The ontology is built as a frame-based Protégé, self-generating XML model. This work is part of the authors' continuing research into the area of generic simulation modelling for enterprises. The generated XML code from the ontology feeds into a stochastic simulation application, Em-Plant, via XPATH queries and instantiates a model on which simulations and experiments can be run. [ABSTRACT FROM AUTHOR]

The paper deals with the methodology of computer modeling and simulation of complex markets with electricity and related products. The methodology is presented using a particular configuration of Central European markets with decentralized trading and international electricity transfers. The modeling approach is based on pure computer numerical solution in discrete state space determined by problems on which the modeled players are expected to decide-price offered for electricity supplied to various markets, breakdown of total power generation into individual commodities (yearly band, monthly band, spinning reserve) and setting bids in auctions for cross-border profiles. Similar approach to decision-making is adopted on the buyer's side. Buyers are expected to strive to contract power supplies in the way that is most advantageous for them. The generated state space is then analyzed using concepts of mathematical game theory. In this way, we obtain a prediction of probable decisions of modeled players in their market competition. Finally, we present a simplified power system forecast for Central Europe for year 2009. [ABSTRACT FROM AUTHOR]

This paper describes a web-based computer network simulator. The system is realised in Java programming language and can be executed as a standalone Java application or Java applet. The environment enables process visualisation and simulation in computer networks with arbitrary topology. Physical and logical IP addressing of computers and router interfaces are supported, as well as working with sub-networks. Routers enable static packet routing, importing static routes in the configuration procedure. Components are configured using configuring dialogue (standard Windows dialogue), or using a line command interface. The processes of forming, addressing, sending, transferring and receiving of frames are visualised, where functions of network devices such as hub, switch and router, are explained. The system enables the creation of many laboratory exercises, which offer students opportunities to follow visually characteristic processes in computer networks. Web-based technology enables the computer network simulator to be used in distance learning. [ABSTRACT FROM AUTHOR]

A novel 6-SSP parallel machine tool and a novel 4SPS+UPU parallel machine tool are presented, and a novel CAD approach is proposed to machine a 3D free-form surface in its normal direction by using the two parallel machine tools. First, by adopting the CAD geometry constraint and dimension-driving technique, the simulation mechanisms of a 6-SSP parallel manipulator with 6-DOF and a 4SPS+UPU parallel manipulator with 5-DOF are created. Second, a 3D free-form surface and a guiding plane of tool path are constructed above the moving platform of the two simulation mechanisms. Third, the tool axis of simulation parallel machine tool is retained perpendicular to the 3D free-form surface. In the light of two prescribed tool paths, the driving limbs and the pose of the moving platform of parallel machine tools are solved automatically and visualized dynamically. [ABSTRACT FROM AUTHOR]

We describe a new type of feedback display based upon ocular accommodation, called the virtual lens, that maintains a focused projection of a CRT image on the retina independent of changes in accommodation, and that replaces the optical image-processing action of the crystalline lens with an arbitrary computable image transform. We describe some applications of the virtual lens in visual psychophysics and virtual environments. [ABSTRACT FROM AUTHOR]

This paper presents a new version (v2.0) of the geothermal techno-economic simulation tool GEOPHIRES [GEOthermal energy for Production of Heat and electricity ("IR") Economically Simulated]. GEOPHIRES combines reservoir, wellbore, and surface plant technical models with cost correlations and levelized cost models to estimate the capital and operation and maintenance costs, instantaneous and lifetime energy production, and overall levelized cost of energy of a geothermal plant. In addition to electricity generation, direct-use heat applications and combined heat and power or cogeneration can be modeled. Various upgrades have been implemented to develop GEOPHIRES v2.0, including: updating the built-in cost correlations, coupling to the external reservoir simulator TOUGH2, enhancing the built-in wellbore simulator, converting the programming language to Python, and making the code open-source. Users are encouraged to build upon the tool, e.g., by implementing their own correlations or coupling to other simulators. In this paper, we discuss the GEOPHIRES v2.0 objectives and history, and we present the software architecture as well as built-in models and correlations. We include two example simulations and quick-start guide on how to run a simulation. [ABSTRACT FROM AUTHOR]

In this paper, a nickel-based amorphous composite coating was obtained on the carbon steel surface by the laser cladding process. The thermal field and stress distribution were simulated by using ANSYS finite element software where the moving heat source and powder feeding were modelled by the "Element birth and death" method. The simulation results were verified by comparing the cross-sectional profile of fusion lines and X-ray stress measurements, respectively. The results on thermal field showed that the cooling rate of the coating could reach up to 10389.15 K/s and it gradually decreased from the outside surface to the interior, which promoted the formation of amorphous phase. The simulated stress field showed that the coating was in the state of tensile stress after cladding and the longitudinal stress was larger than the transverse stress. The coating was experienced with tensile plastic deformation along the laser scanning direction, which resulted in longitudinal residual stress. A higher stress concentration was occurred between the coating layer and substrate, which increased the susceptibility of crack formation. The test results on transverse residual stress were generally consistent with the simulation. On the contrary, the measured longitudinal stress was nearly close to zero, which was not in agreement with the model due to the formation of cracks. [ABSTRACT FROM AUTHOR]

The author outlines the components that typically make up total cost of medical education ownership, suggesting methods by which the costs of these components can be controlled. Components that make up the total cost of ownership include the purchasing price, set up costs, operative costs and long term costs. Repair is expensive and slow and so the cost of having unused equipment needs to be added to the costs of repair.