• ETRI Journal
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• v.32 no.4
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• pp.548-554
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• 2010

The transcutaneous energy transmission system (TETS) composed of a Class-E amplifier may operate at a state away from the optimum power transmission due to the load variation. By introducing the feedback-loop technique, the TETS can keep the optimum state with constant output voltage by adjusting the important design parameters, that is, the duty ratio and frequency of the driving signal and the supply voltage. The relations between these adjusted parameters and the load are investigated. The effectiveness of the feedback technique is validated through a design example with a variable load parameter. The experimental results show that the Class-E amplifier in the feedback loop can keep operating at the optimum state under the condition of up to 50 percent variation of the load value.

• Journal of Sasang Constitutional Medicine
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• v.19 no.1
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• pp.60-77
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• 2007

1. Objectives This is the comparative study with hand-operated measurement method and Automatic measurement method, in order to convert the automatic measurement method. 2. Methods We measured the body of patients(hand-operated Width 5 Places and hand-operated circumference 8 place,Automatic Width 5 and automatic circumference 8 place by 3D body measuring instrument) and analyzed the anthropometric data divding into sex&age. 362 patient's data are used in the analysis. 3. Results and Conclusions 1) 1th circumference variable which standing was not a sasang constitutional difference. 2) Diagnostic accuracy rate of the body measurement was 50-80%. 3) Diagnostic accuracy rate of man is higher than Diagnostic accuracy rate of women 4) Diagnostic accuracy rate of Automatic & hand-operated measuring was not a big difference.

• Journal of Korean Academy of Nursing
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• v.45 no.1
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• pp.129-138
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• 2015

Purpose: The purpose of this study was to report the instrument modification and validation processes to make existing health belief model scales culturally appropriate for Korean Americans (KAs) regarding colorectal cancer (CRC) screening utilization. Methods: Instrument translation, individual interviews using cognitive interviewing, and expert reviews were conducted during the instrument modification phase, and a pilot test and a cross-sectional survey were conducted during the instrument validation phase. Data analyses of the cross-sectional survey included internal consistency and construct validity using exploratory and confirmatory factor analysis. Results: The main issues identified during the instrument modification phase were (a) cultural and linguistic translation issues and (b) newly developed items reflecting Korean cultural barriers. Cross-sectional survey analyses during the instrument validation phase revealed that all scales demonstrate good internal consistency reliability (Cronbach's alpha=.72~.88). Exploratory factor analysis showed that susceptibility and severity loaded on the same factor, which may indicate a threat variable. Items with low factor loadings in the confirmatory factor analysis may relate to (a) lack of knowledge about fecal occult blood testing and (b) multiple dimensions of the subscales. Conclusion: Methodological, sequential processes of instrument modification and validation, including translation, individual interviews, expert reviews, pilot testing and a cross-sectional survey, were provided in this study. The findings indicate that existing instruments need to be examined for CRC screening research involving KAs.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.28 no.1
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• pp.75-82
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• 2020

To compare and analyze the differences between flight simulation and actual flight among 130 army helicopter pilot training subjects, the correlation analysis was performed first through t-testing and multiple regression analysis of individual characteristics and flight simulation and actual instrument flight training, which were analyzed significantly in the age (a3) and service classification (a5) of the six verification factors. This has been shown to be significant, with no difference between the flight simulator and the actual flight. Second, in order to study the correlation between aircraft types, the flight evaluation (v1) was analyzed as a dependent variable for the performance of the flight simulator (KUH: s2, UH60: s3, AH-1S: s5, UH-1H: s6), and the results of the multiple regression analysis of the flight simulator evaluation (s1) were analyzed, in contrast, as a dependent variable, and in conclusion, the training of the flight simulator provided statistical data on the possibility of replacing the actual flight training, which is thought to contribute to the orientation, budget reduction and aviation safety of the pilot training.

• Journal of the military operations research society of Korea
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• v.2 no.1
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• pp.127-143
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• 1976

The purpose of this thesis is to study the optimal arrangement of aircraft instrument panels through the human factors approach. Human factors engineering is the process of effectively fitting the human component to the machine component in any man-machine system. The human factors. are especially important to an aircraft pilot who must constantly shift his attention between the instrument panel within the cockpit and the surrounding area of the aircraft. The preliminary part of this study is to find the general patterns of the Korean pilot's eye movements during their various flying maneuvers, and which instruments require the most attention while in flight. It is assumed that all pilots have a general pattern of eye movement when observing the aircraft instrument panel and that an optimum arrangement would be to minimize the eye travel distance between instruments. In this thesis the arrangements of instruments is taken to be the independent variable and the eye travel distance between instruments the dependent variable. la order to compile the information necessary for this study, sixty Korean Air Force pilots were interviewed and requested to complete information forms. These information forms listed various flying maneuvers and listed each instrument used on the instrument panel. The compilation of the information on these completed forms listed the instruments most frequently used by the pilots. The second part of this study was to determine the optimum instrument arrangement. It was necessary to study the various number of possible arrangements of instruments depending upon the number of instruments involved. Therefore, these instruments are grouped by two major functions, The flight instruments were subdivided into three groups, and the engineering instruments were subdivided into six groups. With this subdivision we arrive at the possible number of arrangements of 4,320. Through the simulation method, total eye travel distance for each of these 4,320 arrangements is calculated and the arrangement which appears to be of optimum distance between the most frequently used aircraft instruments is determined. The results of this study indicate that the optimum distance between instruments would be 33,028cm and that the corresponding distance of the instrument panel now being used is 34,288cm. Therefore, an increased efficiency of $3.8\%$ would be realized if the existing aircraft instrument panel were re-arranged according to layout proposed in this thesis.

• Journal of Power System Engineering
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• v.2 no.2
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• pp.73-80
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• 1998

The identification of drilling joint dynamics which consists of drilling and structural dynamics and the on-line time series detection of malfunction process is substantial not only for the investigation of the static and dynamic characteristics but also for the analytic realization of diagnostic and control systems in drilling. Therefore, We have discussed on the comparative assessment of two recursive time series modeling algorithms that can represent the drilling operation and detect the abnormal geometric behaviors in precision roundshape machining such as turning, drilling and boring in precision diemaking. For this purpose, simulation and experimental work were performed to show the malfunctional behaviors for drilling operation. For this purpose, a new two recursive approach (Recursive Extended Instrument Variable Method : REIVM, Recursive Least Square Method : RLSM) may be adopted for the on-line system identification and monitoring of a malfunction behavior of drilling process, such as chipping, wear, chatter and hole lobe waviness.

• The Journal of the Korea institute of electronic communication sciences
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• v.7 no.6
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• pp.1537-1544
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• 2012

In this paper, a new integration of linear mapping capability with 4-20mA current loop receiver. This module allow user to change instrument variable instantly. Configurations are easy to set by using console command through serial communication port. Break in current loop or faulty current transmitter are easily detect through indicator. The implementation of the module and the test results are discussed.

• Journal of Korean Elementary Science Education
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• v.20 no.1
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• pp.1-7
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• 2001

The purpose of this study is to examine the learner's variables affecting on scientific thinking and scientific process skills. To study this purpose, through the procedure study, the learner's variables were divided into cognitive variable, ego variable, and affective variable, then the questionaire survey through the reconstruction of standardization instrument was made over 120 elementary school fifth grade student in Seoul, Anyang, and Pajoo. The results of this study were as follows: 1) The learner's variables affecting on scientific thinking were cognitive variable and for female students, also affect affective variable. The subordinated catagories of statistically significant degree of explanation were achievement motivation, cognitive level, and cognitive style and another statistically significant correlation were meta-cognition, self regulated learning, self efficacy, and muliple intelligence. 2) The learner's variables affecting on science process skills were cognitive variable and affective variable. And the subordinated catagories of statistically significant degree of explanation were achievement motivation, and cognitive level. And another statistically significant correlation were meta-cognition, self regulated loaming, self efficacy, multiple intelligence, and attribution.

• Near Infrared Analysis
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• v.1 no.1
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• pp.9-17
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• 2000

A variety of standardization methods between two near-infrared (NIR) spectrometers were investigated for the prediction of five constituents in trans-alkylation process. Spectra were collected by two different instruments (one is regarded as mater instrument, other on as slave instrument). Three well-known standardization methods of direct standardization (DS), piecewise direct standardization (PDS) and slope/bias correction of response variable were applied to trans-alkylation samples on the slave instrument. We have examined for a set of reliable standardization samples using smaller number of transfer samples in order to increase efficiency of standardization.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.51 no.6
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• pp.241-251
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• 2002

The effect of sensor faults in direct torque control(DTC) based induction motor drives is analyzed and a new Instrument fault detection isolation scheme(IFDIS) is proposed. The proposed IFDIS, which operated in real-time, detects and isolates the incipient fault(s) of speed sensor and current sensors that provide the feedback information. The scheme consists of an adaptive gain scheduling observer as a residual generator and a special sequential test logic unit. The observer provides not only the estimate of stator flux, a key variable in DTC system, but also the estimates of stator current and rotor speed that are useful for fault detection. With the test logic, the IFDIS has the functionality of fault isolation that only multiple estimator based IFDIS schemes can have. Simulation results for various type of sensor faults show the detection and isolation performance of the IFDIS and the applicability of this scheme to fault tolerant control system design.