• Journal of the Korean Society for Railway
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• v.13 no.3
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• pp.317-326
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• 2010

The purpose of this study is to depict statistically and exploratively the interrelationship among learning orientation, environmental turbulence, and performance in the railway public organizations. To attain this purpose, a questionnaire was provided based on literature survey, and 616 respondent's data received was tested for its validity and reliability. And then, simple and vertical regression analysis were performed. The main findings are as follows: First, learning orientation has a relatively positive effects on performance. Second, environmental turbulence shows a partial moderating effects on the relationship between learning orientation and performance. These findings suggest that learning orientation do exist as an important organizational cultural dimension that contributes to the acquisition of sustainable competitive advantage, and some restrictive factors of public organizations seem to inevitably disrupt the intrinsic necessity of learning in the railway organizations.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.15 no.3
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• pp.113-118
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• 2015

High-power semiconductor devices and microprocessors in factory electrical installation so sensitive to power quality measurements such as harmonic currents, voltage fluctuations, flicker, current imbalance. Therefore, the little change of power quality can influences the productivity of factory electrical machines. Troubleshooting these problems requires accurate measurements and analysis of power quality with monitoring instruments that can effectively locate issues and identify solutions. In this paper, the author presents hand-held power quality monitoring system to locate issues and identify solutions. The proposed system consists of two parts, One is to develop hand-held power meters by using NI(National Instrument) DAQ(Data Acquisition) and WLAN. Another is develop power quality monitoring MMI(Man-Machine Interface) using LabView software. To demonstrate the validity of the proposed algorithm, variable tests are carried out.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.26 no.3
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• pp.725-734
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• 2016

SCADA(Supervisory Control and Data Acquisition) system is widely used for remote monitoring and control throughout the domestic industry. Due to a recent breach of security on SCADA systems, such as Stuxnet, the need of correctly established secure certification of a control system is growing. Currently, EDSA-CRT (Embedded Device Security Assurance-Communication Robustness Test), which tests the ability to provide core services properly in a normal/abnormal network protocol, is only focused on the testing of IP-based protocols such as IP, ARP, TCP, etc. Thus, in this paper, we propose test requirements for DNP3 protocol based on EDSA-CRT. Our analysis show that the specific test cases provide plentiful evidences that DNP3 should follow based on its functional requirements. As a result, we propose 33 specific test case for DNP3 protocol.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2018.11a
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• pp.239-240
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• 2018

In order to improve the productivity and continuous competitiveness of container terminals, it is necessary to make efforts to reduce operational losses at each terminal. As a study on this, it is necessary to study the non-productivity movement based on the shuffle(re-handling) in the yard analysis is needed. In this study, non - productive activity factors were classified by prefecture, transporter, shippers and terminal based on operation data of domestic A terminal. As a result, 14.7% is due to the causes of shipping companies and shipping companies, and in addition, 85.3% of the respondents indicated that they were responsible for the terminal operation. In order to minimize the above factors, it is necessary to reduce the non-productive activity through rapid information processing and pre-information acquisition from shipping companies, and minimize the influence of bulge-out through installation of concrete blocks in the equipment field.

• Journal of Digital Convergence
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• v.17 no.12
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• pp.261-270
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• 2019

The purpose of this study was to identify the factors affecting on contraception behavior among health and non-health university students. Data were collected from April to Jun 2017 from 138 of health and 128 of non-health. The results of multiple regression analysis showed that influencing factors were different by department major. The factors affecting on contraception behavior of health department were sexual experience(ß=0.33), and explanatory power was 23.7%, non-health department was pocket money of over 410,000 won, knowledge acquisition through internet or TV, contraceptive self-efficacy(ß=0.29, 0.24, 0.18), and explanatory power was 22.8%. This study suggests reflecting university students majors when developing educational programs of contraceptive behavior.

• Journal of the Mineralogical Society of Korea
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• v.30 no.1
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• pp.1-9
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• 2017

This study investigated the effectiveness of Unmanned Aerial Vehicle (UAV) and 3D modeling on mine reclamation monitoring. The high spatial resolution of 3.8 cm ortho-mosaic image and Digital Elevation Model (DEM) are constructed based on UAV air survey. The ortho-mosaic image effectively shows mine reclamation activities and recognize objects and topological changes in the image. The comparative analysis of 3D models between UAV based DEM and report based DEM reveals that total amount of $268,672m^3$ additional dumping of contaminated soil is equivalent to 710,000 ton. It concludes that a UAV based survey enables high accuracy spatial information extraction for mine reclamation activities with high efficiency. It is expected that UAV survey will be very effectively used for preliminary data acquisition and project monitoring for mine reclamation activities.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.12 no.1
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• pp.58-68
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• 1998

A computer-controlled system for measuring dielectric hysteresis has been developed. This system consists of the wave generation par\, the high voltage amplifier part, the measurement part, the data acquisition part and the related controll circuits and is interfaced to P.C(personal computer). The applied voltage and its frequency are controlled by P.C . Since the measured datas can be saved in the RAM of P.C, the analysis and the graphics of the datas are very convenient. As a accuracy test, the capcitances of the commercial mica and styroll capacitors were measured by applying high voltage and the results were good agreement with the rating values. In the test of PZT ceramic sample, the typical D-E hysteresis loops were obtained by applying a single frequency voltage to the sample, and $\varepsilon-E$ and D-E hysteresis loops could be measured at the same time by applying a double frequency voltage to the sample.sample.

• Journal of Korean society of Dental Hygiene
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• v.11 no.3
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• pp.363-372
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• 2011

Objectives : The purpose of this study was to pursue an efficient operating plan by surveying the cognition and demand level for major deepening course. Methods : Questionnaire survey was carried out targeting 135 dental hygienists who work in Cheonan and neighboring region. The collected data was performed frequency & percentage, T-test and ANOVA analysis. Results : 1. As for dental hygienists' acquiring academic degree, 77.0% of them responded to have interest. As for a desired route of acquiring academic degree, the major deepening course or Credit Bank System was the highest with 62.2%. 2. As a result of surveying cognition on major deepening course, 73.3% responded to know. A route of having come to know was the largest in senior or friend with 34.8%. Necessity of major deepening course was responded to be necessary with 89.7%. 89.1% of them clarified to have intention of acquiring. 3. The curricular subject, which is desired to be learnt for a plan of operating major deepening course, was the highest in the major field with 63.0%. 4. As a result of comparing an interest, necessity, and intention of acquisition on major deepening course depending on general characteristics, the statistically significant difference wasn't shown. Conclusions : These results suggest that major deepening of course through active public should be aware that many dental hygienists will be subject to a variety of programs and development of clinical course and a practical hands-on education is expected to be strengthened.

• Journal of Soil and Groundwater Environment
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• v.22 no.6
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• pp.120-128
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• 2017

The aim of this study is to analyze the accuracy of SRTM Ver 3.0 and ASTER GDEM Ver 2 over Korea. To enable this, accuracy analysis was performed by using precise DEM which was made with multiple aerial image matching and national base map benchmark. The result of this study identified both SRTM and ASTER have different features. The height of the SRTM was found to be higher (3.8 m on average) at lower elevation and lower (8.4 m on average) at higher elevation. In contrast, the ASTER was found to be lower than the actual height at both lower and higher elevation (2.92 m, 4.51 m on average). The cause of this height bias according to the elevation is due to the differences in data acquisition and processing methods of DEM. It was identified however that both SRTM and ASTER were within allowable limits of error. In addition, RMSE of the SRTM was smaller than the ASTER in comparison to benchmark, and also the bias trend both at higher and lower terrain were similar to the precise DEM which was made with multiple aerial image matching. Therefore, the reliability of SRTM can be considered to be higher.

• Korean Journal of Optics and Photonics
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• v.32 no.5
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• pp.215-219
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• 2021

Recently a system for nondestructive measurement of seedling plants in real time has been attracting attention as an essential element in fields such as the "smart farm". This study reports the simultaneous measurement of anthocyanin accumulations in leaf tissues in a large number of bok choy, using a hyperspectral imaging system. To measure many seedlings simultaneously, an existing hyperspectral imaging system is modified. In this paper, a total of 96 seedlings are measured: 24 each of 4 cultivars. Using the hyperspectral data-acquisition system, 12 seedlings can be analyzed simultaneously within 3 minutes. The hyperspectral imaging technology proposed in this paper is shown to provide an analytic system comparable to destructive chemical analysis. This hyperspectral imaging technology can be applied to a high-throughput plant-phenotyping system, owing to its capability of measuring a large number of specimens at the same time.