• Journal of Navigation and Port Research
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• v.38 no.5
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• pp.519-525
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• 2014

The study was to investigate the effect of the environmental factor on the emotion and satisfaction at the waiting lounge of the Busan International Cruise Terminal. This study focus on tourist at the waiting area in the Busan International Cruise Terminal. The data was collected through self-administered questionnaires and the research performed to face-to-face interview. For data analysis, used SPSS 18.0 and AMOS 18.0 of a structural equation model. The results of the study were found as follows: first, the physical environmental factor of the lounge influenced on the positive emotion. Second, the social factor affected the positive emotion. Finally, emotion affected the positive satisfaction. This study suggested that environmental factor was totally affected by emotion and thus environmental management depended on an individual characteristics of the individual place. The port authority will need more efforts to make a better waiting lounge setting for higher tourist satisfaction.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.48 no.2
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• pp.119-126
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• 1999

Current transformer (CT) saturation may cause a variety of protective relays to malfunction. The conventional CT is designed that it can carry up to 20 times the rated current without exceeding 10% ratio error. However, the possibility of CT saturation still remains if the fault current contains substantial amounts of ac and/or dc components. This paper presents a design method of iron-cored CTs for use with protective relays to prevent CT saturation. The proposed design method determines the core cross section of the CT; it employs the transient dimensioning factor to consider relay's operating time (duty cycle) and dc component as well as ac components contained in the fault current, and symmetrical short-circuit current factor to consider as well as ac components contained in the fault current, and symmetrical short-circuit current factor to consider the biggest fault current. The method designs the cross section of CTs in cases of reclosure and no reclosure.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.44 no.5
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• pp.62-70
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• 2007

In this paper, the boost Power Factor Correction(PFC) technique for Direct Torque Control(DTC) of brushless DC motor drive in the constant torque region is implemented on a TMS320F2812DSP. Unlike conventional six-step PWM current control, by properly selecting the inverter voltage space vectors of the two-phase conduction mode from a simple look-up table at a predefined sampling time, the desired quasi-square wave current is obtained, therefore a much faster torque response is achieved compared to conventional current control. Furthermore, to eliminate the low-frequency torque oscillations caused by the non-ideal trapezoidal shape of the actual back-EMF waveform of the BLDC motor, a pre-stored back-EMF versus position look-up table is designed. The duty cycle of the boost converter is determined by a control algorithm based on the input voltage, output voltage which is the dc-link of the BLDC motor drive, and inductor current using average current control method with input voltage feed-forward compensation during each sampling period of the drive system. With the emergence of high-speed digital signal processors(DSPs), both PFC and simple DTC algorithms can be executed during a single sampling period of the BLDC motor drive. In the proposed method, since no PWM algorithm is required for DTC or BLDC motor drive, only one PWM output for the boost converter with 80 kHz switching frequency is used in a TMS320F2812 DSP. The validity and effectiveness of the proposed DTC of BLDC motor drive scheme with PFC are verified through the experimental results. The test results verify that the proposed PFC for DTC of BLDC motor drive improves power factor considerably from 0.77 to as close as 0.9997 with and without load conditions.

• Korean Security Journal
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• no.32
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• pp.7-32
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• 2012

This study aimed to evaluate the relative status using Analytic Hierarchy Process(AHP) on the spiritual factors of the security martial arts for the guards to perform the best security service. There were 540 participants who were students majored in security martial arts, workers for security and specialists of practical and theoretical security martial arts for this study. The exploratory and confirmatory factor analysis were carried out using the selecting data through literature reviews in the level of the factor-extraction about the spiritual characteristics. The specialists' survey was conducted on the relative status among factors using the spiritual concept structure based on the studied above. Selected data was calculated with SPSS 18.0 for windows, AMOS 5.0, and Expert Choice 2000 software. The conclusion can be made through those process above. First, 4 general factors and 20 detailed factors were found as the result of the factor exploration related to the spiritual characteristics of the security martial arts. The result which was verified on Construction validity of searched factors had stable figures on every standard. In other words, the participants for survey on this study "Spiritual characteristic concepts of the security martial arts" can be evaluated it is valid. The general factors of security martial arts' spirit were conceptualized with Psychological spirit, ethical spirit, martial art spirit, practical spirit through the naming process on the general factors of the security martial arts' spiritual characteristic concepts. The detailed factors of security martial arts' spirit were concentration, self-confidence, self-management, immersion, self-esteem in psychological spirit and sacrifice, justice, royalty, peace, sense of duty in ethical spirit and courtesy, toughness, defense, balance of mind and body, bravery in martial arts and responsibility, cooperation, modesty, determination, professionalism in practical spirit of security martial arts. That is, the conceptualization of security martial arts' spirit was verified that it had validity. Second, the hierarchical model of the security martial arts was composed with 4 superordinate concepts and 20 subordinate concepts. As the result of evaluating relative status based on Spiritual characteristics-hierarchy model, the impotance was proven in order of ethical spirit(.482), martial art spirit(.248), practical spirit(.188), psychological spirit(.083). Also the importance related to spiritual characteristics of security martial arts on subordinate concepts was proven in order of sacrifice(.252), courtesy(.110), sense of duty(.108), responsibility(. 073), royalty(.053), toughness(.052), justice(.049), defense(.038), professionalism(.038), determination(.035), cooperation(.029), self-confidence (.026), bravery(.025), self-esteem(.024), balance of mind and body(.023), peace(.019), concentration(.014), modesty(.013), self-management(.011), flow (.007). To sum up, the spiritual factor related to ethics such as sacrifice, justice, royalty, peace, sense of duty was the most important for the security martial arts.

• Journal of Korean Public Health Nursing
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• v.12 no.1
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• pp.37-54
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• 1998

For the purpose of investigating the job implementation of industrial health nurses catch hold of satisfaction, relational character of influence. A questionnaire survey was carried out on 131 nurses who employed at the manufacture of electronic products$(27.1\%)$, distribution industry$(38\%)$, service station$(22\%)$, construction$(10\%)$, et cetra The tool of this study was modified as completed from kang's(l991) checklist of questions were composed of the performance of nurses' duty(13 items), the factor of main influential character of nurses' job(11 items), job satisfaction(26 items). The results were as follows. 1. Industrial health nurses worked to labor follow up study after physical examination$(100\%)$, medication$(97.1\%)$, workers regular physical examination(95.5%), dressing$(94.1\%)$. 2. The factor of influence of job performance were personal relation$(100\%)$, satisfaction of nurses job performance$(86.7\%)$, environment of workplace$(86.7\%)$. 3. A period of long work experienced nurses felt the highest satisfaction as 3.44 point.

• The Transactions of the Korean Institute of Power Electronics
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• v.4 no.1
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• pp.73-81
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• 1999

A new slip power recovery system applying a switch mode converter to the rotor circuit of the wound rotor induction machine is proposed and investigated in this paper. With the analysis of the steady-state performances of the proposed system, it can be shown that the speed can be controlled by the duty ratio of the converter switch and the several characteristics of a conventional system can be also improved. In particular, the low power factor and the harmonic components in the line current, which are the main disadvantages of the conventional system, is significantly improved, and linear speed regulation can be obtained. Theoretical and experimental results are presented and illustrated to demonstrate the satisfactory working of the proposed system.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.19 no.1
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• pp.66-73
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• 2011

According to U.S. NTSB, from 1989 to 1992, Situation Awareness(SA) was a major factor causing 80% of all aircraft accidents in scheduled airlines. Therefore, the prevention of accidents through effective training in SA became a pivot in aviation safety. Furthermore, during the past 10 years, since all helicopter accidents in Korea were caused by the factors related to SA, an appropriate countermeasure has been required. This study, which uses survey data, examines various factors related to SA that could affect helicopter pilots. Common characteristics of situation awareness factors are that the result from the independent variables which are flight time, duty period and age of a first officer is statistically significant with the result from the independent variables of an instructor pilot's. However, only experience is statistically significant independent variable for factors influencing decision making in emergency situations, but anxiety, expectation and comprehension are not significant.

• The Journal of Korean Association of Computer Education
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• v.15 no.2
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• pp.47-55
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• 2012

We discovered the fact that the most important factor for judging adults' internet addiction in the K-scale method which was developed by Korea National Information Society Agency (NIA), has composed of 4 categories including 20 items, is tolerance and preoccupation factor from the experiments by using data mining techniques. In this research, we propose a new internet addiction diagnostic method based on the degree of tolerance considering users' non-duty internet activities. From some questionnaire participants, their feedbacks for the K-scale and the proposed diagnostic method were collected, and then we confirmed that the proposed user-centered diagnostic method is effective to find undiscovered addicts due to individuals's intention in the K-scale.

• Proceedings of the IEEK Conference
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• 2006.06a
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• pp.1015-1016
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• 2006

The important parameters deciding the fluctuation of Accumulation style surgical operation of ventriculus laser beam are smoothing capacitor, frequency and he characteristics of laser resonator. In this thesis, we control the fluctuation of medical $CO_2C$ laser in realtime by changing Duty-Ratio of IGBT and switching frequency with fixed the smoothing capacitor to improve the fluctuation of laser beam. We detect the light on laser resonator using a CdS photo sensor to improve ripple factor of laser beam and feedback fluctuated signals refined by a band pass filter into the control circuit to stabilize fluctuation actively. There is much to be desired in the realtime controlling technique of the light on Accumulation style surgical operation of ventriculus laser discharge tube in electrical signal. We propose switching control technique with microprocessor and photo sensing technique by controlling switch devices optimum operation and feedback signals detected by a photo sensor into the laser power supply in order to improve ripple factor of the $CO_2$ laser beam.

• The Transactions of the Korean Institute of Power Electronics
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• v.22 no.5
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• pp.404-413
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• 2017

This paper suggests an isolated PFC converter for electric vehicle (EV) chargers with wide-output voltage range. The proposed converter is based on voltage-fed full-bridge structure. All the harmonic and output controls are performed by secondary and primary switches are only operated under a fixed frequency with 50% duty-ratio. In addition, harmonic modulation technique is adopted to obtain a near unity power factor without input current monitoring. The feasibility of the proposed charger has been verified with a 10-kW prototype.