• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.27 no.8
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• pp.75-82
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• 2013

We propose a fiber grating sensor system for condition monitoring of large scale wind turbine blades. For the feasibility test of the proposed sensor system, a down-scaled wind turbine has been constructed and experimented. Fiber grating sensors were attached on a blade surface for distributed strain and temperature measurements. An optical rotary joint was used to transmit optical signals between the FBG sensor array and the signal processing unit. Instead of broadband light source, we used a wavelength-swept fiber laser to obtain high output power density. A spectrometer demodulation is used to alleviate the nonlinear wavelength tuning problem of the laser source. With the proposed sensor system we could measure dynamic strain and temperature profiles at multi-positions of rotating wind turbine blades.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2004.05a
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• pp.326-329
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• 2004

The electric train is a kind of amusement ride and it is installed in a lot of amusement parks. The object of this study was to analyze and to find out of problem about electrical facilities of amusement electric train. For the purpose of this study, we give careful consideration to the technical standard to be Notification of the Ministry of Commerce, Industry and Energy and foreign electrical codes and we carried out an actual condition investigation on twelve amusement electric trains from among domestic amusement parks. As a result, we could how that there is discrepancy between the electrical regulations and the actual condition.

• Journal of The Korea Institute of Healthcare Architecture
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• v.15 no.4
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• pp.23-31
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• 2009

The needs of integrated play and space for both healthy children and children with Disabilities is increasing due to positive effect of integrated play. However, existing plan of play space have not considered children with Disabilities as the user and Integrated Perspective what children and children with Disabilities can do together is insufficient. For these reasons, establishing guideline of the Barrier Free Play Space and Model Development is required to meet the New Paradigm's demands. The purpose of this research is to deduce present condition and problem of play space through the Actual Condition Analysis of domestic Play Space. This study have given careful consideration to the actual condition of play space for 3 types by Types of Installation method. As a result, there are many problems from research point of view and facilities for the disablilities too. Consequently, element of plan and facilities for the disabled which are problems should be shown the direction focused improvement, moreover major task is build a barrier free play space as a place of social integration.

• Journal of Fisheries and Marine Sciences Education
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• v.25 no.3
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• pp.733-742
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• 2013

The Korea has significant tidal current energy resources, but it is so hard to work underwater for tidal turbine installation. Therefore commercial diving work is very important for tidal current generator. Also, Jangjuk channel is vary famous as proper area to generate tidal current energy. Nevertheless, no one is studied about characteristics of commercial diving works with installation of tidal current generator. The purpose of this study is to introduce commercial diving with work types and investigate critical limits of diving working under the conditions, which are working only to minutes at slack tide during the neap tide. As the results, work types are five as like mooring installation, OMAS(Offshore Maintenance Access System), support structure installation, cable and turbine installation. Here, the original construction period is expected about 4 months, but the construction take 18 months to complete. The cause of extends construction period is insufficiency of researching tidal current conditions at the site and ignorance of slack tide which need to secure diving working time. Total diving working times are 110th during 18 months, the highest percentage of diving times is turbine installation about 43.6 %, and cable, mooring installation and support structure construction are 27.3 %, 15.5 %, 13.6 %, respectively. On the basis of this study, estimation of times of commercial diving is possible with work types of tidal current power, and has a significance as basic data to determining construction period.

• Journal of the Korean Institute of Rural Architecture
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• v.18 no.3
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• pp.25-34
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• 2016

The purpose of this study is to investigate installation status of information facilities and condition of walking road influencing to psychological safety of walking tourists. For this purpose, four roads for walking tour are selected; the course no. 16 of Jeju Olle Trail, Sarabong Byeoldobong walkway in Jeju and the course no. 8 of Bougil, Gyeongpo Lake walkway in Gangneung. Facilities installed on roads for walking tour are classified into four facilities; safety facility, information facility, amenity facility, local cultural facility. In order to consider installation status of information facilities and condition of walking road influencing to psychological safety of walking tourist, a field experiment was conduced focusing on the course no. 16 of Jeju Olle Trail. Thirteen cases were happened as confusing situation while walking tour. Of the 13 cases, the situation of being lost and wandering on the trail accounted for six cases. In contrast to the expectation that the situation of being lost and wandering would occur only at a crossroads, it is not that such situation took place at specific places like a crossroads or where direction signs were inaccurate. Walking tourists of this field experiment also confronted situations of having lost confidence about continuing the ongoing direction, of having anxiety over walking a walking trail, of feeling discomfort caused by walking and of being offended by uncomfortable or messy areas of walking trial. These confusing situations are happened inappropriate installation of direction sign, so direction sign is needed to install more carefully and detailed.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.59 no.1
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• pp.1-8
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• 2023

In this study, the stability of fishing boat inducing the change of fishing lamp in accordance with the installation of induction lamp in comparison with metal halide lamp was investigated. Inclining test for 8.55 ton class of hair-tail angling fishing boat was performed in order to find a GM and light weight. A stability calculation of the target fishing boat on the basis of KST-SHIP program was evaluated. The stability of the fishing boat with a metal halide lamp such as induction lamp according to the result obtained by the inclining test is slightly different, and the stability is not so much affected. Due to the induction lamp installation, the wind area increased by about 3.178 m². Before installing the induction fishing lamp, G₀M was found to be 0.209 at full load departure and 0.296 at departure from fishing ground. After installing the induction lamp, the full load departure condition is 0.178 and the fishing ground departure condition is 0.260. The G₀M value before and after installation of the induction fishing lamp shows a difference of about 3% at the full load departure condition. The value of the critical angle of inclination definition showed a difference of about 16%. Despite these differences, it is lower than the regulations; it was confirmed that there will be no significant difference unless it is in an overloaded state.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.29 no.7
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• pp.28-37
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• 2015

Owing to the variability of large-scaled wind power system, the development of wind farm management technologies and related compensation methods have been receiving attention. To provide an accurate and reliable output power, certain wind farm adopts a specified management system including a wind prediction model and grid expectation solutions for considering grid condition. Those technologies are focused on improving the reliability and stability issues of wind farms, which can affect not only nearby system devices but also a voltage condition of utility grid. Therefore, to adapt the develop management system, an expectation process about voltage condition of Point of Common Coupling should be integrated in operating system for responding system requirements in real-time basis. This paper introduce a grid imposing method for a real-time based wind farm management system. The expected power can be transferred to the power flow section and the required quantity about reactive power can be calculated through the proposed system. For the verification process, the gauss-seidel method is introduced in the Matlab/Simulink for analysing power flow condition. The entire simulation process was designed to interwork with PSCAD for verifying real power system condition.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.27 no.3
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• pp.65-78
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• 2013

To analyze influences under open fault conditions in switching devices, an integrated simulation and condition monitoring scheme for a permanent magnet synchronous generator (PMSG) based variable speed grid-connected wind turbine system are presented. Among various faults in power electronics components, the open fault in switching devices may arise when the switches are destructed by an accidental over current, or a fuse for short protection is blown out. Under such a faulty condition, the grid-side inverter as well as the generator-side converter does not operate normally, producing an increase of current harmonics, and a reduction in output and efficiency. As an effective way for a condition monitoring of generation system by online basis without requiring any diagnostic apparatus, the estimation schemes for generated voltage, flux linkage, and stator resistance are proposed and the validity of the proposed scheme is proved through comparative simulations.

• Proceedings of the KSR Conference
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• 2008.06a
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• pp.1587-1593
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• 2008

After the incendiary fire accident at Daegu subway, discussion of PSD installation started to prevent accident from fall. safety accident and big accident. Following these paradigm, the purpose of the study is to analyze the present condition of current installation of PSD in our country and suggest an improvement scheme for the future PSD operation extension. Using the SWOT analysis and we analyze the inner and outer capability of PSD installation. We try to find a counter plan strategy for PSD installation improvement scheme through the analysis.

• Journal of the Korean Geosynthetics Society
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• v.16 no.4
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• pp.1-11
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• 2017

In this study, 1/6 small-scale model tests of helical piles were conducted to evaluate their installation time and ultimate capacities. Model sand layers were constructed using sand pluviating method to produce uniform soil relative density. For installation of different helical piles varying locations (vertical center-to-center spacings of 50 mm and 150 mm) of helix plates, two different rotation speeds of 15 rpm and 30 rpm were implemented. Cone penetration equipment was installed within the hallow section of the helical pile to increase ultimate capacity of helical pile and to evaluate soil properties of plugged soils and soils below pile tip after installation of the piles. Based on the test results, the most fasted installation was possible under the condition of "rotation speed of 30 rpm and center-to-center spacing of 50 mm", and the highest ultimate capacity was mobilized under the condition of "rotation speed of 30 rpm and center-to-center spacing of 150 mm with cone penetration implementation."