• Journal of Navigation and Port Research
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• v.26 no.2
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• pp.221-226
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• 2002

To provide reliable data for drift prediction models, field experiments were carried out in the coastal region off Busan port. Four different size of vessels(10, 30, 50, 90G/T ton) were deployed for the experiment. Among them G/T 50ton class vessel was equipped with instruments measuring the currents, winds, headings and trajectory data. In the rest of vessels only the position data were recorded for the purpose of target divergence study. The trajectories of each vessel were measured by DGPS(Differential Global Positioning System) and collected by APRS(Automatic Position Reporting System). The experiment was done in wind of 2~10m/s and current of 0.5~1.5m/s. The leeway was derived by subtracting surface current velocity from target drifting velocity. The leeway rate of G/T 50ton vessel was found to be about 3.6% and the computed leeway speed equation was $U_L$=0.042 W - 0.034. The processed leeway angle data were deflected by $-30^{\circ}$~$40^{\circ}$ from the direction of ship drift.

• Journal of the Korean Society of Safety
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• v.20 no.1 s.69
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• pp.107-112
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• 2005

The purpose of this study is to propose and introduce Accidents Prevention Remedies(APRs) and their priorities especially for Accident Causing factors(ACFs) drawn by surveying and analyzing how much foreign workers in Korea have been exposed to dangers at a construction site. At frist as a result of the analysis of the questionnaire which 59 foreign industrial trainees working at the construction sites in Seoul-Kyunggi area had responsed, 12 ACFs and 11 APRs were put out by using the SPSS programme. Then, through the Analytic Hierarchy Process(AHP) about the questionnaire from 96 safety and civil engineers who have experienced in managing foreign labor at the construction sites all over the country, the APRs given their priorities of relative importances are as follows; First, it is absolutely necessary that every working order to foreign workers should be made more definitely in accordance with a concrete process schedule. Second, the owners should increase investments in improving foreign workers' welfare in order to minimize their potential human error. Third, Korean language education programme for simple technical terms should be made and executed at least.

• Journal of Institute of Control, Robotics and Systems
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• v.15 no.2
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• pp.240-248
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• 2009

Modem version of supersonic jet fighter aircraft must have been guaranteed appropriate controllability and stability in HAoA(High Angle of Attack). The HAoA flight control law have two parts, one is control law of departure prevention and the other is control law of departure recovery support. The control laws of departure prevention for advanced jet trainer consist of HAoA limiter, roll command limiter and rudder fader. The control laws of departure recovery support are consist of yaw-rate limiter and MPO(Manual Pitch Override) mode. The guideline of pitch rocking using MPO mode is simple, but operating skill of pitch rocking is very difficult by the pilot with inexperience of departure situation. Therefore, automatic deep stall recovery system is necessary. The system called the "Automatic Pitch Rocker System" or APRS, provided a pilot initiated automatic maneuver capable of an aircraft recoveries in situations of deep stall, speed and altitude. This paper addresses the design and validation for APRS to recovery of an deep stall without manual pitch rocking by the pilot. Also, this system is designed to recovery of speed, attitude and altitude after deep stall recovery using ATCS (Automatic Thrust Control System) and autopilot. Finally, this system is verified by real-time pilot evaluation using HQS (Handling Quality Simulator).

• Proceedings of the KIEE Conference
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• 1996.11a
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• pp.99-102
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• 1996

In general, real power system is not stopped for reason of its test. And then we have no way to verify its reliability on real power system. In this paper we present the real time simulation technique of the APRS(Automatic Power Reconfiguration System) before it is applied in real power system. We used the Real Time Digital Simulator constructed in KEPRL And we applied the power system model which is reduced because of RTDS capacity. Also, We prescent the method Interface between target system(APRS) and RTDS. Last, We provide the test results and the meaning.

• Journal of the Korean Society for Marine Environment & Energy
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• v.8 no.1
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• pp.17-22
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• 2005

The movement of drifting ships on the sea is closely related to marine environmental forces such as waves, currents, winds, etc. To develop a prediction model for trajectories oi drifting ships, an experiment on the movement of drifting ships was carried out in the Southeastern Sea of Korea. Five types of ships including a lire raft and tour ships with G/T 10tons, G/T 2o tons, G/T 50 tons, and G/T 80 tons, were considered in the experiment. The G/T 50 ton class ship was used as a base ship for obtaining the currents, winds and heading angles of ship following the trajectory. The trajectory of each ship was measured by DGPS(Differential Global Positioning System) and collected using APRS(Automatic Position Reporting System) installed on the base ship. The error range in position fix of DGPS are approximately ±1 m. The drift speed of ship in the experiment was between 3％ to 5％ of wind speed and drift direction of ship was deflected by ±90° from wind direction. Also, the heading of drifting ship was normal to wind direction.

• Proceedings of the KIEE Conference
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• 2001.05a
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• pp.49-51
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• 2001

Recently, according to a rapid increase of the power demand, the KEPCO's 154kV lines are continuously expanded and become to the more complex loop system. As a result of increase of the fault capacity and the unbalance of power load flow, the circuit breaker have been exceeding the capacity limit of those in the loop power system. To solve this problem, APRS application will be necessary more and more.

• Asia pacific journal of information systems
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• v.4 no.2
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• pp.83-130
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• 1994

Software development of large scale program such as Operating System or University Total Information System is lengthy and costly process. In order to reduce cost, time and risk, there is currentry general acceptance of the need for Software Reuse System during the whole development cycles. In this paper, (from a practical point of view), the problem of existing reuse system methodology is analyzed and an implement method of software reuse system is presented. Also using this method Application Program Reuse System(APRS) which supports all phase of software life cycles is designed and implemented. This application program reuse system which is based on common language is considerably shown to reduce communication Error of requirement specification between systems analyst and end-user.

• Proceedings of the KIEE Conference
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• 1997.07c
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• pp.851-853
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• 1997

This paper presents an algorithm for real-time restoration of radially operated 154kV loop system. Restoration procedure consists of 4 procedures; recognition of faults, identification of fault locations, seperation of fault locations and restoration of blackout areas. This algorithm adopts expert's knowledge for safe and accurate operation of the real-time restoration system (APRS: Automatic Power Reconfiguration System).

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.23 no.3
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• pp.103-108
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• 2012

Objectives : The aim of this study is to investigate the effectiveness of treatment with osmotic-release oral system methylphenidate (OROS-MPH) on quality of life (QOL) in children with attention-deficit hyperactivity disorder (ADHD). Another aim is to assess the relationship between change in QOL and other factors including children's symptoms and academic performance or parents' depression and parenting stress. Methods : A total of 111 medication-naive children with ADHD in a multicenter, open-label, 12-week trial of OROS-MPH completed an evaluation using diverse rating scales at two time points; at baseline and after 12 weeks of treatment. Scales for investigation of children included the Parent Report Form-Children's Health and Illness Profile-Children's Edition (PRF-CHIP-CE) on QOL, the ADHD Rating Scale-IV on symptoms, and the Academic Performance Rating Scale (APRS). The Beck Depression Inventory and Parenting Stress Index were used for assessment of their parents. Results : Total scores for mean PRF-CHIP-CE increased from $207.9{\pm}26.7$ at baseline to $226.3{\pm}25.9$ after 12 weeks of treatment (p<.001). The change of APRS showed the strongest correlation with the increment of PRF-CHIP-CE scores (Pearson coefficient=0.561, p<.001), even after controlling for other factors (partial correlation coefficient=0.420, p<.001). Conclusion : Treatment with MPH-OROS results in improvement of QOL in children with ADHD in Korea. The advance in academic performance plays a key role in this change of QOL.

• Environmental Engineering Research
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• v.21 no.4
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• pp.384-392
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• 2016

The aim of this study was to investigate the removal efficiency of $17{\alpha}$-methyltestosterone (MT) from aqueous solution by Salvinia cucullata Roxb. ex Bory in an active plant-based reactor with a specific focus on linear regression analysis for the sorption phenomena of MT onto the plant roots. A high performance liquid chromatographic method using UV detection (245 nm) was used to analyse the samples. The batch experiments of the active plant reactor (APR) were established to investigate the ability of Salvinia cucullata to remove MT from the liquid phase. The results revealed that 40% and 60% removal of MT from the liquid phase was observed at 5 min. and at 4 h, respectively. Salvinia cucullata can effectively remove MT from the aqueous solution in APRs. Kinetic studies revealed that the sorption phenomena of MT by Salvinia is best described using a linearized pseudo - second order model. Based on the kinetic parameters, it is likely that during the first 4 h of the contact (t = 0 to t = 4 h) sorption is the major driving mechanism of the disappearance of MT from aqueous solutions. However, at higher MT concentrations, diffusivity of MT has a significant effect on the migration of MT from the bulk stream to the root surface. The isotherm analysis revealed that the sorption kinetics favourably followed pseudo second-order. The results of isotherm analysis have indicated that the sorption of MT onto the root surfaces of Salvinia cucullata was favourable and almost irreversible.