• 자동차안전학회지
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• 제12권3호
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• pp.43-51
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• 2020

Currently, the second level of the six stages of self-driving technology, as defined by SAE, is commercialized, and the third level is preparing for commercialization. The purpose of ACC is to be evaluated as a system useful for preventing and preventing accidents by minimizing driver fatigue through longitudinal speed control and relative distance control of the vehicle. In this regard, for the study of safety assessment methods in the practical environment of ACC. Distance measurement method using monocular camera and data acquisition equipment such as DGPS are utilized. Based on the evaluation scenario considering the domestic road environment proposed by the preceding study, the relative distance obtained from equipment such as DPGS and the relative distance using a monocular camera in the actual test is verified by comparing and analyzing the safety assessment. The comparison by scenario results showed a minimum error rate of 3.83% in Scenario 1 and a maximum of 14.61% in Scenario 6. The cause of the maximum error is that the lane recognition is not accurate in the camera image and irregular operation conditions such as rushing in or exiting the surrounding area from the walkway. It is expected that safety evaluation using a monocular camera will be possible for other ADAS systems in the future.

• 한국해양공학회지
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• 제19권6호통권67호
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• pp.58-63
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• 2005

The estimation of springing responses for recent ships is carried out, and application to a ship design is described. To this aim, springing effects on hull girder were re-evaluated, including non-linear wave excitations and torsional vibrations of the hull. The Timoshenko beam model was used to calculate stress distribution on the hull girder, using the superposition method. The quadratic strip method was employed to calculate the hydrodynamic forces and moments on the hull. In order to remove the irregular frequencies, we adopted 'rigid lid' on the hull free surface level, and addedasymptotic interpolation along the high frequency range. Several applications were carried out on the following existing ships: The Bishop and Price's container ship, S-175 container ship, large container, VLCC, and ore carrier. One of them is compared with the ship measurement result, while another with that of the model test. The comparison between the analytical solution and the numerical solution for a homogeneous beam-type artificial ship shows good agreement. It is found that Most springing energy comesfrom high frequency waves for the ships having low natural frequency and North Atlantic route etc. Therefore, the high frequency tail of the wave spectrum should be increased by $\omega$$\^{-3}$ instead of $\omega$$\^{-4}$ or $\omega$$\^{-5}$ for the springing calculation.

• Journal of Advanced Marine Engineering and Technology
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• 제20권2호
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• pp.92-92
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• 1996

Recently, with the rapid development in the oceanic systems such as the oceanic structures and vessel, there occurs much interest in the impingement erosion-corrosion. In this paper, Cu-metal was tested by using of erosion apparatus with water-jet type and was investigated under the behaviour of impingement erosion-corrosion according to various environmental conditions, and the properties of Cu-metal were evaluated through the measurement by weight loss, weight loss rate, protective efficiency. The results were compared with those obtained using Cu-metal applied to cathodic protection and Cu-alloys added to Zn or Al-metal. As a basis of those results, the best protective efficiencies could be taken as using cathodic protection method and Cu-alloy with Al & Zn material addings, and will be suggested as the fundamental data of the anti-impingement erosion-corrosion on Cu-metal of impeller material for oceanic centrifugal pump.

• Journal of Advanced Marine Engineering and Technology
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• 제20권2호
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• pp.24-31
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• 1996

Recently, with the rapid development in the oceanic systems such as the oceanic structures and vessel, there occurs much interest in the impingement erosion-corrosion. In this paper, Cu-metal was tested by using of erosion apparatus with water-jet type and was investigated under the behaviour of impingement erosion-corrosion according to various environmental conditions, and the properties of Cu-metal were evaluated through the measurement by weight loss, weight loss rate, protective efficiency. The results were compared with those obtained using Cu-metal applied to cathodic protection and Cu-alloys added to Zn or Al-metal. As a basis of those results, the best protective efficiencies could be taken as using cathodic protection method and Cu-alloy with Al & Zn material addings, and will be suggested as the fundamental data of the anti-impingement erosion-corrosion on Cu-metal of impeller material for oceanic centrifugal pump.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2000년도 춘계학술대회논문집A
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• pp.218-223
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• 2000

The shot peening is largely used for a surface treatment in which small spherical parts called shots are blasted on a surface of a metallic components with velocities up to 100m/s. This treatment leads to an improvement of fatigue behavior due to the developed compressive residual stresses, and so it has gained widespread acceptance in the automobile and aerospace industries. The residual stress profile on surface layer depends on the parameters of shot peening, which are, shot velocity, shot diameter, coverage, impact angle, material properties etc. and the method to confirm this profile is only measurement by X-ray diffractometer. Despite its importance to automobile and aerospace industries, little attention has been devoted to the accurate modelling of the process. In this paper, the simulation technique is applied to predict the magnitude and distribution of the residual stress and plastic deformation caused by shot peening with the help of the finite element analysis.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2018년도 춘계 학술논문 발표대회
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• pp.251-252
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• 2018

Cool roof coating materials generally use white color which has the highest reflectance, but it is a tendency to apply various colors because it can cause glare and fatigue of a nearby building user due to the urban beauty and high reflection. This study when applying color diversity material cool roof coating was carried out as a basic research for the degree of solar radiation reflectance change. Experiment result. As a result of the measurement of the reflectance of each specimen, white showed the best reflectance in the near infrared region, and black had the lowest reflectance. Also, in case of brown, it was confirmed that the reflectance of solar radiation in the near extrinsic region is lower than that of gray.

• 한국해양공학회:학술대회논문집
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• 한국해양공학회 2004년도 학술대회지
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• pp.173-178
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• 2004

The estimation of springing responses for recent ships are carried out and application to a ship design are described. To this aim, springing effects on hull girder were re-evaluated including non-linear wave excitations and torsional vibrations of the hull. The Timoshenko beam model was used to calculate stress distribution on the hull girder by the superposition method. The strip method was employed to calculate the hydrodynamic forces and moments on the hull. In order to remove the irregular frequencies, we adopted 'rigid lid' on the hull free surface level and added asymptotic interpolation along the high frequency range. Several applications to the existing ships were carried out. They are Bishop and Price's container ship, S-175 container ship, large container, VLCC and ore carrier. One of them is compared with ship measurement result while another with that of model test. Comparison between analytical solution and numerical one for homogeneous beam type artificial ship shows good agreement. It is found that most springing energy came from high frequency waves for the ships having low natural frequency and North Atlantic route etc. Therefore, the high frequency tail of the wave spectrum should be increased by $\omega^{-3}\;instead\;of\;\omega^{-4}\;or\;\omega^{-5}$ for springing calculation.

• 근관절건강학회지
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• 제4권2호
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• pp.262-276
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• 1997

The purposes of this study are 1) to modify a self-help program for patients having fibromyalgia, 2) to revise instruments to measure the self-efficacy and impact of fibromyalgia; and 3) to test the effects of the program in terms of self-efficacy, physical activities, and clinical symptoms. The subjects of this study were persons diagnosed as fibromyalgia at a university hospital. For the first two purposes, six patients were selected. Twenty three subjects for the third purpose were selected and assigned to experimental and control group on the base of their residence. Thirteen were assigned to the experimental group, while 10 to the control group. Instruments selected for revision were self-efficacy scale and fibromyalgia impact profile. On the basis of the text developed by Arthritis Foundation, a program for patients with fibromyalgia was tentatively developed. Instruments for measurement of self-efficacy and impact of fibromyalgia were revised to show high reliabilities. Results obtained by utilization of the program were as follows : 1) There were no increase of self-efficacy and physical activities. 2) There were no improvement of the number of tender points and pain. 3) There were improvement of depression, fatigue and sleep impairment. These findings indicate the needs for modification of the program with emphasis of exercise for relaxation of tender points, increases of enactive action and vicarious learning.

• 한국안전학회지
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• 제34권6호
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• pp.58-64
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• 2019

Over the past decades there has been a growing body of researches that examines the psychological traits related to safety outcomes. After briefly reviewing the relationships between psychological dispositions and safety outcomes, we empirically examine the relationships with 2 samples of 1,102 participants. Fifteen psychological dispositions (big 5 personality, locus of control, cognitive failure, affection from job and relations, 4 achievement goal orientations, self-efficacy, fatigue, and depression) and four psychological outcomes (safe behavior, unsafe behavior, accidents, and injuries) are examined. After covariance structure modeling variances of safety outcomes are well explained by simple 4 dispositions of consciousness, mastery-approach goal orientation, self-efficacy, and depression. We name them 'core safety disposition', and name four psychological outcomes 'safety consciousness', and the relationships between those latent variables are stronger than between measurement variables. We propose core safety disposition as a cause of safety consciousness, and discuss implications for research and practices.

• 기본간호학회지
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• 제18권1호
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• pp.19-27
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• 2011

Purpose: This study was conducted to develop a respiratory nursing program using recorder playing for patients with asthma and to determine the effects of the program. Method: Participants were 26 patients with asthma (experimental group: 13, control group: 13). The experimental group participated in the respiratory nursing program for six months from April, to October, 2007. Content included playing a recorder, group education about asthma, and educational messages including cellular phone messages. The control group received usual care during the six months. Results: In this research the respiratory nursing program using recorders was developed in 3 stages: initial stage, advanced stage, and wrap up stage. Compared to the control group, fatigue status in the experimental group improved significantly as well as level of forced expiratory volume in 1 second. However significant differences were found in sleep status, mood, or quality of life. Conclusions: These results suggest that this respiratory nursing program for symptom management of patients with asthma led to improvements in self care activity. Nursing interventions are needed to maintain and further enhance the quality of life of these patients and the interventions should be implemented over a transition period.