• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.44 no.6
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• pp.530-536
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• 2016

The handling quality simulator including high fidelity flight mechanics model is indispensable component to design and verify the flight control system. Korea Aerospace Industries, LTD. (KAI) has been performing LCH (Light Civil Helicopter) core technology development program regarding automatic flight control system (AFCS) software development. And KAI has been developing flight mechanics model using FLIGHTLAB to design and evaluate the AFCS flight control law. This paper presents the handling quality assessment environment development results through the combining FLIGHTLAB with a legacy simulator. And this paper details the FLIGHTLAB model, application development process and FLIGHTLAB interface design. The developed handling quality assessment environment has been demonstrated with the ADS-33E hover and pirouette MTE (Mission Task Element) maneuver simulation.

• Journal of Korea Society of Industrial Information Systems
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• v.7 no.2
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• pp.74-81
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• 2002

In general, a multipath generator consists of a time delay generator, phase rotator, and amplitude attenuator, and is implemented mostly in an analog manner. Analog, or partially analog versions of a multipath generator is disadvantageous in that they may suffer from problems associated with component aging and adjustment, signal fidelity degradation stemming from repeated A/D and D/A conversion use of high frequency to achieve fine i.e., subsample fractional tin delays. This paper presents the design and implementation methodology of a full digital multipath generator which can be used in performance evaluations of digital terrestrial television as well as communications, receivers. In particular, an efficient practical method is proposed which can achieve both integer and fractional time delays simultaneously, without placing restrictions on the allowable system master clock frequency. The proposed algorithm lends itself to minimizing hardware implementation cost by relegating some fixed put of the computation involved to an IBM PC. The proposed multipath generator occupies only a single digital board space, and its experimental results are provided to corroborate the proposed implementation methodology.

• The Journal of Korean Academic Society of Nursing Education
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• v.21 no.1
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• pp.54-64
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• 2015

Purpose: The purpose of this study was to investigate the effects of simulation in nursing education based on caring for elderly cognition disorder patients. The education consisted of a caring program for patients that included a process of assessment of a patient's mental status, diagnosis of the patient's health condition, and intervention to address the problems by using therapeutic communication. Methods: A nonequivalent control group pretest-posttest design was used. A total of 69 subjects (undergraduate students) participated in the education and they were assigned to two groups: the experimental group (n=32) and the control group (n=37). Data-gathering structured questionnaires that included communication competence, academic self-efficacy, and attitudes about the elderly. The data were collected from October 2013 to December 2013, and statistical analyses were conducted with-test and t-test using the SPSS 21.0 program. Results: With respect to education, there was significant improvement in communication competence in the experiment group (t=2.41, p=.022) compared with in the control group (t=.69, p=.494). However, there was no statistically significant difference in academic self-efficacy and attitude about the elderly. Conclusion: Simulation-based education should continue to be developed further for better elderly-patient care. Integrated education in particular using a high-fidelity simulator will contribute to improvements in nursing competence in this area.

• Nuclear Engineering and Technology
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• v.51 no.8
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• pp.1871-1885
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• 2019

The deterministic MOC code STREAM of the Computational Reactor Physics and Experiment (CORE) laboratory of Ulsan National Institute of Science and Technology (UNIST), was initially designed for the calculation of pressurized water reactor two- and three-dimensional assemblies and cores. Since fast reactors play an important role in the generation-IV concept, it was decided that the code should be upgraded for the analysis of fast neutron spectrum reactors. This paper presents a coupled code - TULIP/STREAM, developed for the fast reactor assembly and core calculations. The TULIP code produces self-shielded multi-group cross-sections using a one-dimensional cylindrical model. The generated cross-section library is used in the STREAM code which solves eigenvalue problems for a two-dimensional assembly and a multi-assembly whole reactor core. Multiplication factors and steady-state power distributions were compared with the reference solutions obtained by the continuous energy Monte-Carlo code MCS. With the developed code, a sensitivity study of the number of energy groups, the order of anisotropic P_N scattering, and the multi-group cross-section generation model was performed on the k_eff and power distribution. The 2D core simulation calculations show that the TULIP/STREAM code gives a k_eff error smaller than 200 pcm and the root mean square errors of the pin-wise power distributions within 2%.

• Journal of Service Research and Studies
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• v.8 no.1
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• pp.1-12
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• 2018

The current research investigates an optimal design for the service system, which refers to the entire process of implementing, providing, and utilizing wisdom assets. We analyzed the intrinsic commonality of wisdom assets and services, and carried out research based on optimality in fidelity to service essence. The essential characteristics of service are horizontality, interactivity, harmonization, and relationship. It is suggested that the operating process can be implemented in the best condition when the wisdom asset service system is designed based on the four essential characteristics of services. It has been demonstrated that the entire process of production, delivery, marketing and quality control of wisdom contents can be designed on the basis of the essence of wisdom and service. After designing a basic service model, detailed service models are presented. The purpose of this study was to solve the problems of the material civilization society which is suffering mentally and to design the social service model which is high in productivity but mentally healthy. By supplementing and deepening the results of this study, it will be possible to develop and implement desirable social service model in which all societies live a happy life.

• Elastomers and Composites
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• v.47 no.3
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• pp.188-193
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• 2012

The fatigue analysis and lifetime evaluation are very important in design procedure to assure the safety and reliability of the rubber components. Recently, the design, analysis and evaluation technology was required to achieve the high quality, fidelity, reliability of rubber products. However, rubber manufacturing companies of our country have uesd the method of trial and error and experience in the process of a compound mixing, manufacturing and improvement of rubber properties. The objectives of this study are to establish the test methods of rubber material and to make the database of rubber material properties and to evaluate the performance of rubber components and to construct the prediction system of fatigue life. Fatigue lifetime prediction methodology of the rubber component was proposed by incorporating the finite element analysis and fatigue damage parameter from fatigue test.

• Journal of the Korea Institute of Military Science and Technology
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• v.18 no.1
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• pp.46-54
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• 2015

Wargame simulators are widely used in the field of defence modeling and simulation. Because of increasing importance of communication effects on the warfare, the war game simulator is also required to reflect communication effects. One way to satisfy the requirement is the interoperation simulation between war game simulator and communication effect simulators. This paper shows the application of interoperation simulation between war game and communication effect simulators using HLA(High-Level Architecture)/RTI(RunTime Infrastructure). The war game simulator mainly deal with the engagement of troops and the troops communicate each other at the mission execution level. In the other hand, The communication effect simulator perform communication actions between the troops in the engineering level. Using the interoperation simulation, we can reflect the communication effects on the war game simulation. We show various applications of the interoperation simulation with the point of the war game and communication effect simulator. with a case study, we explain the interoperation simulation improves the reality and fidelity of the war game simulator and how the interoperation simulation can be applied to developing doctrines and real communication system.

• Journal of Korean Academy of Nursing
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• v.47 no.6
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• pp.842-853
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• 2017

Purpose: This study was conducted to identify effects of debriefing based on the clinical judgment model for nursing students on their knowledge, skill performance, clinical judgment, self-confidence and learner satisfaction during simulation based end-of-life care (ELC) education. Methods: Simulation based ELC education was developed in six steps as follows: selection of learning subjects and objects, development of learning tools, a trial run of simulation-based education, students' skill training, and evaluators' training. Forty-eight senior nursing students (25 in the experimental group and 23 in the control group) participated in the simulation-based ELC education using a high-fidelity simulator. Debriefing based on the clinical judgment was compared with the usual debriefing. Results: ANCOVA showed that there were differences in knowledge (F=4.81, p=.034), skill performance (F=68.33, p<.001), clinical judgment (F=18.33, p<.001) and self-confidence (F=4.85, p=.033), but no difference in satisfaction (t=-0.38, p=.704) between the experimental and control groups. Conclusion: This study found that debriefing based on the clinical judgement model is effective for supporting nursing students for reflecting on clinical judgment and improving their diverse competencies in complex clinical settings such as ELC.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.2A
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• pp.132-138
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• 2009

Cognitive radio is considered as a promising solution to scarce spectrum problem. The primary object of cognitive radio is to increase spectral efficiency, while causing limited interference to primary users who are using the spectrum. Hence, an essential part of cognitive radio systems is spectrum sensing which determines whether a particular spectrum is occupied or not by a primary user at a particular time. However, sensing decision of each individual secondary user alone may not be reliable enough due to shadowing and multipath fading of wireless channels. The so called hidden terminal problem makes the problem even worse, possibly yielding undesired interference to the primary users. Recently, cooperative spectrum sensing is emerging as a remedy to these problems of individual sensing. Cooperative sensing allows a group of secondary users to share local sensing information to extract a global decision with high fidelity. In this paper, we investigate a cooperative spectrum sensing algorithm based on hard decisions of local sensing outcomes. Specifically, we propose an effective scheme for combining local decisions by introducing weighting factors that reflect reliability of the corresponding secondary user. Through computer simulations, the performance of the proposed combining scheme is compared with that of the conventional scheme without weighting factors in various environments.

• International Journal of Automotive Technology
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• v.6 no.2
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• pp.107-117
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• 2005

A distributed hardware-in-the-loop simulation (HILS) platform is developed for designing an automotive engine control system. The HILS equipment consists of a widely used PC and commercial-off-the-shelf (COTS) I/O boards instead of a powerful computing system and custom-made I/O boards. The distributed structure of the HILS system supplements the lack of computing power. These features make the HILS equipment more cost-effective and flexible. The HILS uses an automatic code generation extension, REAL-TIME WORKSHOP$^{ (RTW$^{) of MATLAB$^{ tool-chain and RT-LAB$^{, which enables distributed simulation as well as the detection and generation of digital event between simulation time steps. The mean value engine model, which is used in control design phase, is imported into this HILS. The engine model is supplemented with some I/O subsystems and I/O boards to interface actual input and output signals in real-time. The I/O subsystems are designed to imitate real sensor signals with high fidelity as well as to convert the raw data of the I/O boards to the appropriate forms for proper interfaces. A lot of attention is paid to the generation of a precise crank/ earn signal which has the problem of quantization in a conventional fixed time step simulation. The detection of injection! command signal which occurs between simulation time steps are also successfully compensated. In order to prove the feasibility of the proposed environment, a simple PI controller for an air-to-fuel ratio (AFR) control is used. The proposed HILS environment and I/O systems are shown to be an efficient tool to develop various control functions and to validate the software and hardware of the engine control system.