387,732 research outputs found

    Automation of finite element aided design of induction motors using multi-slice 2D models

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    Purpose – To develop a practical design tool employing a general purpose electromagnetic finite element (FE) software package to perform automated simulation and performance analysis of induction motors in a design and optimisation process. Design/methodology/approach – Recent publications identified a suitable approach in applying 2D finite-element analysis to 3D problems. This, together with other similar work carried out on brushless DC motors, set out a framework for program development. Performance of the program was validated against practical test data. Findings – Finite-element analysis-based design tools can be realistically employed within a design office environment and are capable of providing solutions within acceptable time scales. Such tools no longer require user expertise in the underlying FE modelling method. The multiple slice technique was employed to model skew in three-phase induction motors and it was established that a four-slice model provides a good balance between accuracy and speed of computation. Research limitations/implications – Program development was based on one commercial FE software package and comparison with practical test data was not exhaustive. However, the approach outlined confirms the practical application. Future work could consider alternative approaches to optimisation. Practical implications – Computing hardware and commercially available 2D FE software have developed sufficiently to enable multi-slice techniques and optimisation to be employed in the analysis and design of machines. Originality/value – This paper provides a practical illustration of how commercial electromagnetic software can be employed as a design tool, demonstrating to industry that such tools no longer need to be bespoke and can realistically be used within a design office

    Advances in POST2 End-to-End Descent and Landing Simulation for the ALHAT Project

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    Program to Optimize Simulated Trajectories II (POST2) is used as a basis for an end-to-end descent and landing trajectory simulation that is essential in determining design and integration capability and system performance of the lunar descent and landing system and environment models for the Autonomous Landing and Hazard Avoidance Technology (ALHAT) project. The POST2 simulation provides a six degree-of-freedom capability necessary to test, design and operate a descent and landing system for successful lunar landing. This paper presents advances in the development and model-implementation of the POST2 simulation, as well as preliminary system performance analysis, used for the testing and evaluation of ALHAT project system models

    Army-NASA aircrew/aircraft integration program (A3I) software detailed design document, phase 3

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    The capabilities and design approach of the MIDAS (Man-machine Integration Design and Analysis System) computer-aided engineering (CAE) workstation under development by the Army-NASA Aircrew/Aircraft Integration Program is detailed. This workstation uses graphic, symbolic, and numeric prototyping tools and human performance models as part of an integrated design/analysis environment for crewstation human engineering. Developed incrementally, the requirements and design for Phase 3 (Dec. 1987 to Jun. 1989) are described. Software tools/models developed or significantly modified during this phase included: an interactive 3-D graphic cockpit design editor; multiple-perspective graphic views to observe simulation scenarios; symbolic methods to model the mission decomposition, equipment functions, pilot tasking and loading, as well as control the simulation; a 3-D dynamic anthropometric model; an intermachine communications package; and a training assessment component. These components were successfully used during Phase 3 to demonstrate the complex interactions and human engineering findings involved with a proposed cockpit communications design change in a simulated AH-64A Apache helicopter/mission that maps to empirical data from a similar study and AH-1 Cobra flight test

    Small Projects Rapid Integration and Test Environment (SPRITE): Application for Increasing Robustness

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    Marshall Space Flight Center's (MSFC) Small Projects Rapid Integration and Test Environment (SPRITE) is a Hardware-In-The-Loop (HWIL) facility that provides rapid development, integration, and testing capabilities for small projects (CubeSats, payloads, spacecraft, and launch vehicles). This facility environment focuses on efficient processes and modular design to support rapid prototyping, integration, testing and verification of small projects at an affordable cost, especially compared to larger type HWIL facilities. SPRITE (Figure 1) consists of a "core" capability or "plant" simulation platform utilizing a graphical programming environment capable of being rapidly re-configured for any potential test article's space environments, as well as a standard set of interfaces (i.e. Mil-Std 1553, Serial, Analog, Digital, etc.). SPRITE also allows this level of interface testing of components and subsystems very early in a program, thereby reducing program risk

    Use of Simulation Involving Standardized Patients as an Education Program to Increase Nurse Confidence in Caring for Patients with Drug and Alcohol Problems

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    Purpose: The purpose of this pilot project was to test the effectiveness of a simulation exercise using standardized patients on nurses’ perceived confidence in caring for patients with drug and alcohol problems. Method: The project was a mixed methods pre-test and posttest design to assess whether simulation using standardized patients was effective in improving nurses’ confidence in caring for patients with problematic drug and alcohol use issues. Qualitative data was obtained by interviewing participants using a semi structured interview. Results: All nurses reported a positive experience as a result of participating in the simulation exercises. Use of simulation as a learning exercise to improve nurses’ confidence in caring for behaviorally challenging patients with drug and alcohol use was effective. Conclusion: Caring for patients with drug and alcohol use problems is a challenge particularly in the medical surgical environment where the nurses do not necessarily possess an adequate skill set to manage the associated behaviors. Development of an educational program using patient simulation exercises may increase nurses’ confidence and ability to care for patients with dual illicit drug and/ or alcohol use disorders on medical surgical units

    Design and Development of 3D approach for Electromagnetic Theory Courseware

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    This paper will explain about research on development of three dimensional (3D) courseware for EMT subject that have been offers to all Malaysia Technical University Network (MTUN). The EMT courseware was included a multimedia software, three dimensional environment, and exercises for student to be done to test their understanding after using the courseware. This courseware covers up to the whole chapters for EMT subject in multimedia terms but only one chapter that will be using 3D simulation deeply which is coordinate system and transformation. Moreover, this paper explains about the theoretical framework which is divided into three parts which are analysis, design and development, and evaluation. For the second objectives, the instructional design model is used to see the effectiveness of the 3D courseware for teaching and learning starting from defining education media, how to measure the content, authoring program and systematic instructional design and include also the simulation of 3D object. ID model focused on learning and teaching aspects and science education, education process and by using multimedia interactive module. This courseware has six modules which are Note, Tutorial, Simulation, Glossary, Help, and Past Year. Next phase is Development phase, and this phase focus on development of 3D courseware

    A Modular Test-Suite for the Validation and Verification of Electromagnetic Solvers in Electromagnetic Compatibility Applications

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    Computational solvers are increasingly used to solve complex electromagnetic compatibility (EMC) problems in re- search, product design, and manufacturing. The reliability of these simulation tools must be demonstrated in order to give confidence in their results. Standards prescribe a range of techniques for the validation, verification, and calibration of computational electro- magnetics solvers including external references based on measure- ment or for cross-validation with other models. We have developed a modular test-suite based on an enclosure to provide the EMC community with a complex external reference for model valida- tion. We show how the test-suite can be used to validate a range of electromagnetic solvers. The emphasis of the test-suite is on the features of interest for EMC applications, such as apertures and coupling to cables. We have fabricated a hardware implementa- tion of many of the test-cases and measured them in an anechoic chamber over the frequency range to 1–6 GHz to provide a mea- surement reference for validation over this range. The test-suite has already been used extensively in two major aeronautical research programs and is openly available for use and future development by the community.This work was supported by the U.K. Engineering and Physical Sciences Research Council under the Flapless Air Vehicle Integrated Industrial Research program under Grant GR/S71552/01, and from the European Community’s Seventh Framework Program FP7/2007-2013 under Grant 205294 on the High Intensity Radio-frequency Field Synthetic Environment research project

    Modular, Autonomous Command and Data Handling Software with Built-In Simulation and Test

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    The spacecraft system that plays the greatest role throughout the program lifecycle is the Command and Data Handling System (C&DH), along with the associated algorithms and software. The C&DH takes on this role as cost driver because it is the brains of the spacecraft and is the element of the system that is primarily responsible for the integration and interoperability of all spacecraft subsystems. During design and development, many activities associated with mission design, system engineering, and subsystem development result in products that are directly supported by the C&DH, such as interfaces, algorithms, flight software (FSW), and parameter sets. A modular system architecture has been developed that provides a means for rapid spacecraft assembly, test, and integration. This modular C&DH software architecture, which can be targeted and adapted to a wide variety of spacecraft architectures, payloads, and mission requirements, eliminates the current practice of rewriting the spacecraft software and test environment for every mission. This software allows missionspecific software and algorithms to be rapidly integrated and tested, significantly decreasing time involved in the software development cycle. Additionally, the FSW includes an Onboard Dynamic Simulation System (ODySSy) that allows the C&DH software to support rapid integration and test. With this solution, the C&DH software capabilities will encompass all phases of the spacecraft lifecycle. ODySSy is an on-board simulation capability built directly into the FSW that provides dynamic built-in test capabilities as soon as the FSW image is loaded onto the processor. It includes a six-degrees- of-freedom, high-fidelity simulation that allows complete closed-loop and hardware-in-the-loop testing of a spacecraft in a ground processing environment without any additional external stimuli. ODySSy can intercept and modify sensor inputs using mathematical sensor models, and can intercept and respond to actuator commands. ODySSy integration is unique in that it allows testing of actual mission sequences on the flight vehicle while the spacecraft is in various stages of assembly, test, and launch operations all without any external support equipment or simulators. The ODySSy component of the FSW significantly decreases the time required for integration and test by providing an automated, standardized, and modular approach to integrated avionics and component interface and functional verification. ODySSy further provides the capability for on-orbit support in the form of autonomous mission planning and fault protection

    Enhancing students’ confidence, competence and knowledge with Integrated Skills Challenge

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    Introduction/background: In today's complex healthcare environment, new nursing graduates are expected to master nursing skills in a timely manner and become critical thinkers with the capacity of solving complex healthcare problems efficiently. The increased complexity of the clinical setting requires competence-building begin in introductory courses, establishing foundational skills for critical thinking and prioritisation. In the healthcare professions, teaching and learning methods are focused on integration of clinical knowledge and skills. However, traditional teaching and learning methodologies do not always facilitate the development of a requisite level of these clinical skills. For the Master of Nursing Studies (MNSt) students whose program is shortened this means the acquisition of these skills must be achieved more rapidly. Aim/objectives: The purpose of this study is to investigate the feasibility of developing simulation scenarios (Integrated Skill Challenge [ISC]) as a supplemental teaching-learning strategy to enhance the transfer of student self-confidence and competence to the clinical nursing environment. Methods To examine potential effects of ISC on the MNSt students, a pilot study was conducted including 52 participants. Data were collected weekly over 11 week period by using pre and post-test design. Results: Analysis showed a significant increase in the confidence, competence and knowledge. Confidence, competence and knowledge scores increased when students were pre-loaded with knowledge prior to performing in the ISC. Results generally indicated that the ISC had the anticipated effects. Conclusions: This study reveals a high feasibility of developing simulation scenarios as an active learning methodology and that it should be developed further and piloted on a larger sample

    Developing Modified ADS-33D Helicopter Maneuvers for the Shipboard Environment

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    The Office of the Secretary of Defense chartered the Joint Shipboard Helicopter Integration Process (JSHIP), Joint Test and Evaluation (JT&E) Program to improve Joint interoperability between U.S. Navy ships and U.S. Army/Air Force helicopters. One effort of the JSHIP JT&E Program was to improve the modeling and simulation tools and fidelity levels associated with conducting Joint shipboard helicopter operations, for both testing agencies and operational users. The UH-60A helicopter and the LHA class ship were identified as the highest priority helicopter-ship pair for operational forces and also allowed JSHIP to enhance models that currently existed. Enhancing the visual model of an LHA ship was a primary effort for the research and testing community in order to accurately replicate the shipboard visual cueing environment. Evaluating enhanced visual models in a research flight simulator in order to reduce actual shipboard flight testing or expand wind launch/recovery envelopes required the use of more aggressive and precise flight maneuvers than standard shipboard takeoffs and landings. The U.S. Army’s Aeronautical Design Standard 33D (ADS-33D) contained flight test industry accepted maneuvers of sufficient aggressiveness and precision, but were not designed for, or intended to be flown from the deck of a ship at sea. The methodology and procedure used to modify selected ADS-33D flight maneuvers so that they could safely be executed aboard an LHA class ship is presented in this thesis, along with the final maneuver descriptions, locations, and flight tolerances. The results of the shipboard test program and follow-on simulator assessment are not presented here, as they fall outside the scope of this thesis. However, conclusions from the at-sea flight tests relating to development of the modified ADS-33D were included. The flight test philosophy, methodology, and lessons learned while developing the modified ADS-33D maneuvers for the shipboard environment are the primary conclusions drawn
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