• Journal of Electrical Engineering and Technology
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• v.9 no.3
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• pp.991-996
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• 2014

Power frequency magnetic field is still a critical problem for new construction of overhead power transmission lines in Korea because most people have been concerned about possibly carcinogenic effects of it. Although reference level of power frequency(60Hz) magnetic field has been set to 200uT in ICNIRP guidelines published in 2010, Korean government has no intention of adjusting 83.3uT specified by law in 2006 to this new reference level in consideration of people's concerns for the time being. Regardless of the current regulated magnetic field value, electric utility company has been trying to reduce magnetic field in the residential area in the vicinity of overhead power transmission lines to take into account of public concerns on the long-term effect of magnetic fields. In an effort to reduce magnetic field, engineering side has made considerable efforts to develop passive loop based, cost-effective mitigation technique of power frequency magnetic field more than ten years. In order to verify developed power frequency magnetic field mitigation technique based on passive loop, a horizontal type of passive loop was designed and installed for commercially operating 154kV overhead power transmission line for the first time in Korea. The measurement results before and after the installation of passive loop showed that magnetic field could be reduced to about 20%. The electrical environmental effects such as AN, RI and TVI were assessed before and after the installation of passive loop and these values were complied with the requirements specified by electric utility. It has been confirmed from the field test results that passive loop could be commercially and cost-effectively utilized to mitigate power frequency magnetic field.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2019.11a
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• pp.87-88
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• 2019

Leading Lights and Sector Lights provide a navigable channel, heading reference and a visual indication. Mariners can take easily a reference bearing or line of position. The Busan North Port needed to install a sector light to resolve blind sections because of Busan Port Redevelopment Project D-1 Block Construction Plan. And also the busan new port needed to install a sector light to give safety indication because navigation conditions will be changed due to removal of the to-island. For this reason, design development was made for installation of sector lights. In addition, the results of design development were compared with the AtoN simulation and verified. This paper is expected to be very useful for installing Sector Lights to guide the vessel to port safely in Korea.

• Proceedings of the KSR Conference
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• 2008.11b
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• pp.79-87
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• 2008

The major objective of this study is to investigate the effective maintenance system for the infrastructure on the conventional lines in which the tilting train runs. In order to the speed-up of conventional lines that have many curve lines, there needs a improvement construction of substructure such as the straight or double track work and so on. But in this case, it needs to have a plenty of the cost and the period. Therefore, the tilting train which provides the high-speed service effectively in curve tracks was developed. Besides, the efficiency prediction and the linear fitness of the existing conventional lines for a tiling train service were examined on the preceding study which was the development of track system innovation technology for speed-up of them. So, in this paper we propose the more effective maintenance method than the existing it in order to securing the high reliability and safety classified by the infrastructure, in analyzing foreign materials and the maintenance as well as the inspection cycle concerning domestic infrastructures of the track and the catenary etc. on the railway. And we look forward to playing a decisive role as reference material for the effective improvement of the existing maintenance about the infra on the conventional lines for the commercial service of the tilting train.

• Korean Institute of Interior Design Journal
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• v.26 no.6
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• pp.180-190
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• 2017

The subway station is not only an effective means to solve urban traffic problems, but also a kind of representative city shelters with a variety of functions such as urban beauty and disaster prevention. At the same time, the subway station as public facilities need activate the urban functions and through the effective design schemes for a variety of the facade of underground entrance to improve users' awareness and reliability for the subway station as a city shelters. This study is conducted to purpose the design direction considering design and disaster preventing characteristics of the underground subway station entrance. In addition, it will provide a basic reference for the subway station in the renovation and construction. The study is composed of literature reviews and field survey. The literature reviews through papers and documents related to the city shelters, the components and characteristics of city shelters, and components and characteristics of facade design of underground entrance at subway station. Before the field survey through the online surveys with evacuation capabilities and screening only the subway station. And field survey is conducted on the site with careful observation and confirmation. Last cluster analysis were applied to the finally selected samples by the SPSS Win18.0

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.65 no.3
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• pp.171-177
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• 2016

Noise problem that occurs in living environment is a big trouble in the economic, social and environmental aspects. In this paper, the filtered-X LMS algorithms, the adjoint LMS algorithms, and the robust adjoint LMS algorithms will be introduced for applications in active noise control(ANC). The filtered-X LMS algorithms is currently the most popular method for adapting a filter when the filter exits a transfer function in the error path. The adjoint LMS algorithms, that prefilter the error signals instead of divided reference signals in frequency band, is also used for adaptive filter algorithms to reduce the computational burden of multi-channel ANC systems such as the 3D space. To improve performance of the adjoint LMS ANC system, an off-line measured transfer function is connected parallel to the LMS filter. This parallel-fixed filter acts as a noise controller only when the LMS filter is abnormal condition. The superior performance of the proposed system was compared through simulation with the adjoint LMS ANC system when the adaptive filter is in normal and abnormal condition.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2008.05a
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• pp.369-373
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• 2008

This case analyze the point of trouble and reform processing construction on input design to resolve the problem for setting tower in front of narrow base at the 154kV OO Transmission Line substaion. Hereafter the input design are presented for the basic reference data which the case a point of trouble and reform contents, input design of special shape tower and the foundation on substation input design cannot be setted by standard type of tower because of narrow base and cannot keep clerance overhead transmission conductor input to the substion.

• Earthquakes and Structures
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• v.17 no.4
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• pp.411-424
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• 2019

In this study, a numerical model of a shield tunnel with an assembled segmental lining was built. The seismic response of the segmental lining of the section of the shield tunnel in Line 1 of the Chengdu Metro is analyzed as it passes through the interface of sand-cobble and mudstone layers. To do so, the node-stress seismic-motion input method was used to input the seismic motion measured during the 2008 Wenchuan earthquake, and the joint openings and dislocations associated with the earthquake action were obtained. With reference to the Ethylene-Propylene-Diene Monomer (EPDM) sealing gaskets used in the shield tunnels in the Chengdu Metro, numerical simulation was applied to analyze the contact pressure along the seepage paths and the waterproof property under different joint openings and dislocations. A laboratory test on the elastic sealing gasket was also conducted to study its waterproof property. The test results accord well with the numerical results and the occurrence of water seepage in the section of the shield tunnel in Line 1 of the Chengdu Metro during the 2008 Wenchuan earthquake was verified. These research results demonstrate the deformation of segmental joint under earthquake, also demonstrate the relationship between segmental joint deformation and waterproof property.

• Journal of architectural history
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• v.31 no.6
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• pp.59-68
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• 2022

This paper is an architectural historical study on Chimi of Hwangnyongsa Temple. In this research, the shape and cross-section of the chimi are reviewed. The results of the study are as follows. The chimi is a form in which the head part facing the maru is omitted, and the upper and lower body are separated. The upper and lower bonds are assembled into a two types of joint throughout the side of the torso, and then bound with an iron strap. Because of the absence of ridge line in the front, and the narrow curved surface which makes the side plate close to the plane, the entire cross-section is triangular, and the rear plate maintains the shape of the chimi. The naerimmaru connected to the side of the chimi has a slope, so it is clear that the chimi was used on the woojingak-jibung(hipped-roof), and the wing part and back of the chimi are erected on the side roof. The height of the yongmaru and chunyeomaru is about the same and the roofing tiles of those are in contact. The roofing tiles of chunyemaru should be cut to fit the angle of the contacting part. The maru is 30 stories high of roofing tiles as a result of the on-board survey. Based on reference on the shape and timing of the production of chimi, the height of chimi, and the maru is believed to have been built before the Unified Silla Period and used in buildings with at least seven-kan frontage. Buildings corresponding to these construction conditions can be seen as Central hall and East hall in Hwangnyongsa temple.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2007.11a
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• pp.995-998
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• 2007

The number of households old over as much as 20 years is expected to get increased rapidly more than 1,000,000(1 million). As a measure to this fact remodeling is being revitalized over the country. parking lots expansion actually takes up a great deal of weight among the requirement for remodeling. When constructing a parking lot for enlargement, the way of going into the main building determines such construction features as selection of Retaining Wall Method, installation of an elevator, parking measure of capacity, etc. This study derived the affecting factors for selecting the way of going into the main building when constructing an underground parking lot. In a research way, we examined the features on each method of going into the main building in an apartment complex through an in-depth interview with some experts after investigating the method of enlarging an underground parking lot and going into the main building. After that, we derived the affecting factors for selecting the way of going into the main building. The affecting factors include constructability, convenience, economic efficiency as a high level as well as existence and nonexistence of basement and removal, safety of current building, parking measure of capacity, amenity, inhabitant traffic line, construction expenses and construction duration as a low one. This study will be applied as a reference for selecting the way of going into the main building when constructing an underground parking lot especially targetted on an old apartment house.

• Journal of Korean Tunnelling and Underground Space Association
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• v.23 no.5
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• pp.339-357
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• 2021

As the construction of trans infrastructure using the underground tunnel have been rapidly increased, various nearby excavation of existed underground facility including subway structure has been occurred in urban tunnelling. The concern and worry relating to the safety and stability of the existed facility by nearby excavation is becoming the key issues in urban tunnelling. In this study, it was conducted for existed the subway station structure at Seoul subway line which was closely located in the new Dongbuk urban metro railway to determine the behavior characteristics of station structure according to adjacent tunnel construction. Also, it was reviewed the evaluation of the safety zone and excavation method for subway structure. And after a review of damage evaluation, track irregularities and structural calculation by using a numerical analysis, stability of the subway structure according to nearby tunnel excavation was evaluated to be secured. This study is expected to be applied as useful reference in advance if you need to review the effects of existed structure according to nearby construction in complex urban tunnelling.