• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2019년도 추계학술대회
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• pp.270-270
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• 2019

관성측정장치(Inertial Measurement Unit)는 선박, 잠수함, 항공기 등 여러 응용분야에서 적용되어 자세 측정 영역에 주로 사용되고 있지만, 이런 장비는 고가의 장비이기 때문에 특수 분야에서만 한정적으로 이용되어 왔다. 본 연구에서는 저가의 관성측정장치(Inertial Measurement Unit)를 이용하여 실시간으로 선박의 속도와 방향, 중력, 가속도를 측정함으로써 선박의 감항성을 확인하며, 더 나아가 실선 선박의 저항 및 조종성능 추정을 위한 유체력 미계수 추정을 위한 연구방법을 고안하였다. 이에 본 연구는 실제 해상에서 선체 운동요소를 계측하고, 계측된 데이터의 처리 및 해석을 통하여 선박의 종합적인 안전성 평가 및 실선의 저항 및 조종성능 추정을 행하였다.

• 대한조선학회논문집
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• 제42권6호
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• pp.566-574
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• 2005

Reduction of a ship's rolling is the most important performance requirement for improving the safety of the crew on board and preventing damage to cargos as well as improving the comfort of the ride. A mass driving anti-rolling system (MO-ARS) might be one candidate of several systems against the ship's rolling. As the movable range of the mass on the ship is finite, the control system must include restriction on the mass position to protect the device and the ship. This restriction usually causes windup phenomenon and control performance is deteriorated seriously. Two control algorithms, anti-windup control and saturated sliding mode control, are studied in this paper. Control performance and robustness problem are checked out by numerical simulations.

• 한국항행학회논문지
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• 제23권4호
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• pp.289-295
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• 2019

국제항로표지협회에서는 해양 분야에서 활용하는 백업항법시스템의 경우 항만 입출항시 10 m의 수평정확도를 보장하도록 요구하고 있다. 대표적인 해양분야의 백업항법시스템인 eLoran은 10 m 이내의 수평 정확도를 만족함이 증명되었지만, 수신환경에 따라 항법성능이 저하되기도 한다. 특히 수신 안테나 주변의 잡음 및 멀티패스 등으로 인한 요인으로 인해 특정 상황에서는 항법 자체가 불가능해지기도 한다. 본 논문에서는 이러한 환경에서 항만입출항 조건의 수평정확도 요구성능을 만족하기 위하여 UAV(unmanned aerial vehicles)를 활용한 선박의 백업항법시스템을 설계하였다. eLoran 신호 수신에 영향을 주는 주변 환경의 영향을 감소시키기 위하여 UAV에 카메라, IMU센서, eLoran 안테나 및 수신기를 장착하였으며, 선박의 안테나보다 높은 곳에서 카메라를 이용하여 랜드마크를 추적하고 일정 범위 내에서 eLoran 신호 수신과 위치 및 자세를 제어하도록 설계하였다. 선박에서는 UAV로부터 수신한 영상 및 자세 정보와 eLoran 신호를 이용한 선박기반 측위결과를 이용해 항만 입출항 시 수평정확도 요구성능을 만족할 수 있다.

• 대한조선학회논문집
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• 제42권6호
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• pp.666-672
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• 2005

Reduction of a ship's rolling is the most important performance requirement for improving the safety of the crew on board and preventing damage to cargos as well as improving the comfort of the ride. A mass driving anti-rolling system (MO-ARS) might be one candidate of several systems against the ship's rolling. In this paper, three types of MD-ARS, two passive and one active devices, are developed for small ships. After they are installed on the cabin of the small leisure boat, respectively, a series of performance test is conducted before and after operating them. Through the test, it is confirmed that the roll responses of the ship are pretty well reduced by the MO-ARS.

• 대한가정학회지
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• 제27권4호
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• pp.123-137
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• 1989

The purpose of this study is to examine parental attitudes perceived by juvenile delinquents and to provide the basic material on the problem of juvenile delinquency. For this purpose, this study examines 1) the relation-ship between the juvenile delinquents' social demographic characteristics and the juvenile delinquents' view of parental attitudes 2) the correlation between the juvenile delinquents' social demographic characteristics and the content and the motive of delinquency, 3) the content and the motive of delinquency in accordance with the juvenile delinquents' view of parental attitudes. For the subject of this study, 318 juvenile delinquents who were in the custody of the institution in An-Yang were selected, and questionnaire sheets were used. Of 318 questionnaire sheets, 221 sheets were analyzed by statistical methods, and the data were analyzed by frequency, percentage, average, t-test, x-test, and F-test; 1. There is a significant difference in the juvenile delinquents' view of their fathers in accordance with their fathers' age. Namely, the younger the father is, the more the juvenile delinquent wants his father to be less negative. There is a significant difference in the juvenile delinquents' view of their mothers according to the existence of step-sibling. Juveniles with step-siblings deny their mothers' inconsistent attitude more than the juveniles without a step-sibling. 2. The social demographic characteristics influencing the content of juvenile delinquency are juvenile's age, the degree of education, the father's age, the style of possessing house and the region of a dwelling. The motive of delinquency show a significant difference according to the juvenile's age. 3. According to the results of studying the correlation between the view of parental attitudes and the content and the motive of delinquency, there is a significant difference in the father's protective attitude, and the content of delinquency as well as in the mother's positive denial, her rigid control, her inconsistent attitude and the content of delinquency. The subordinate domains are opposite to the traditional conception that the father is stern and the mother is peronssive. Today our society encourages the parents' equal and democratic attitude toward their children and the juvenile's view of parental attitudes is discordant with the reality. The juvenile delinquents' view of parental attitudes reflects the equalitariansim of the contemporary society but is influenced by the traditional view of the parents.

• 대한조선학회논문집
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• 제33권2호
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• pp.36-43
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• 1996

현재 전 세계적으로 해상교통의 주역이 되리라고 생각되는 고속선에 대한 시험 연구를 수행하였다. 본 논문은 주행중 고속선에 가장 문제가 되는 파도중의 운항자세를 제어하는 시험을 수행한 결과이다. 선형은 카타마란 선형을 선택하였으며, 운항자세를 제어하기 위하여 선수와 선미부분에 제어판을 장치하였다. 자세제어 시스템으로는 제어판과 제어판 구동장치, 운동 계측장비로 되어있으며, 운동 계측장비로부터 데이타를 취득하고, 제어판 구동장치로 신호를 보내기 위하여 A/D, D/A보드를 각각 1장씩 사용하였다. 이 장비를 이용하여 규칙 정면파중의 고속선의 운항자세를 제어하는 시험을 수행하였으며, 실험결과로부터 자세제어 시스템이 작동하지 않을 때와 작동할 때의 차이를 비교하였다. 비교결과 종동요(Pitch)는 진폭이 많이 감소하였으나, 상하동요(Heave)는 많이 감소하지 않았다.

• 제어로봇시스템학회논문지
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• 제3권3호
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• pp.238-243
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• 1997

A new transfer alignment algorithm using the velocity and the quaternion partial matching methods is proposed to reduce the effect of a ship's Y-axis flexure on the performance of azimuth error estimation of Kalman filter. The simulation results show that it can significantly reduce the effect of Y-axis flexure on error estimation by the transfer alignment algorithm. As its results, azimuth transfer alignment error is reached up to 3 mrad under proper roll and pitch attitude motion of the ship.

• 한국군사과학기술학회지
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• 제16권6호
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• pp.745-751
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• 2013

In naval gun firing, firing accuracy comes from the combination of each component's accuracy in CFCS (Command and Fire Control System) like tracking sensors and gun. Generally, battery alignment is done to correct the error between gun and tracking sensor by using boresight telescope on harbor and sea. But normally, the battery alignment can compensate only the static alignment error and ignore dynamic alignment error which is caused by own ship movement. There was no research on this dynamic alignment error until now. We propose a new way to analyze dynamic arrangement error by using image of boresight telescope. In case of the dynamic alignment error was due to time delay of own ship attitude information, we propose the way to compensate it.

• 한국의류학회지
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• 제10권1호
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• pp.59-67
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• 1986

The purpose of this study was to identify the characteristics of fashion leaders in relation to attitude toward change and socioeconomic level among Dae Gu woman as well as among rural women living on the suburbs of Dae Gu: and to compare the characteristics of these urban women in a mass society with the rural women living in a traditional society. Measures selected for this study consisted of the Schrank Fashion Opinion Leadership Inventory(1973), the Schrank ana Sugawara Attitudes Toward Change Inventory(1977), and socioeconomic level. The fashion Innovation Inventory was developed by author which consisted of a list of clothing and accessory items selected after surveys to local stores, campus, and main streets, and study of fashion magazines for the current seasons. The data from 280 respondents were analyzed by Pearson corrleation coefficients, analysis of variance, and t-test. The results were as followers : 1) A significant relationship was found between fashion leadership and socioeconomic level for both urban and rural women. High attitude toward change was significantly related to high fashion innovativeness and high fashion opinion leadership among the urban groups. re significant relationship was found between fashion opinion leadership and attitude toward change among the rural sample. 2) A significant difference was found in attitude toward change scores of four urban sub-sample groups : fashion innovators, fashion opinion leaders, fashion innovative communicators(who exhibit high scores on both fashion innovativeness and fashion opinion leader-ship), and non-fashion innovative communicators. No significant difference was found in attitude toward change scores of four rural sub-sample groups. No significant differences were found in socioeconomic level of four sub-sample groups for both urban and rural women.

• Strategy21
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• 통권44호
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• pp.377-416
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• 2018

The purpose of this study is to investigate the effects of the job stresses perceived by R.O.K. naval crews on turnover intentions and job satisfactions. Especially, this study aims to derive the policy implication for the trait characteristics by comparing the job attitude between the surface naval ship and submarine crew. For this purpose, we surveyed 1,000 naval crews. Then, multiple regression analysis was performed. Next, a T-test was conducted to test statistical significance of group differences. First, the job stresses perceived by naval crews were higher in the order of physical environments, overworks, compensation incompetence, lacks of autonomy, and conflicts with people. Second, the job stresses perceived by submarine crews were higher than that of surface naval ship crews. It was also proved statistically significant by the T-test. Third, the physical environments, lacks of autonomy, conflicts of relativity, and inadequate compensation stress have a positive statistically significant effect on turnover intentions of naval crews. Fourth, lacks of autonomy, conflicts of relativity, and inadequate compensation factors have a statistically significant negative effect on the job satisfactions of naval crews. Finally, multiple regression analysis was performed between the independent and dependent variables of the naval crews, and the policy implications were derived.