• Journal of the Korean Wood Science and Technology
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• v.42 no.6
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• pp.708-713
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• 2014

Trusses are widely used for wooden houses in the areas where wood construction in generalized for residential housings such as North America, Australian, New Zealand. In Korea, joist and rafter system is generally used because of the production cost, transportation cost and lack of experience required for truss manufacturing. In this study, roof trusses and flat trusses were manufactured by using oriented strand board (OSB) gusset plates for field assembly and tested under bending load to obtain the allowable loads. The allowable load and the actual load of 6m span roof trusses were 10.60 kN and 5.26 kN, respectively, which is regarded to be sufficient for use in construction. The allowable load and the actual load of 6m span floor flat trusses were 7.18 kN and 7.43 kN, respectively. For flat trusses, the allowable load is slightly lower than the actual load but the difference in very small, and it is thought that flat trusses can be used for construction by applying small change of structures and members.

• Korean Journal of Environment and Ecology
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• v.31 no.1
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• pp.24-29
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• 2017

This study was conducted to identify nesting habits and breeding biology of barn swallow in Gwangju, Korea, for the breeding season 2012 to 2014. All nests were attached to vertical walls and roofs of buildings and situated at mean height $2.9{\pm}0.3m$ above ground with nest diameter $18.2{\pm}3.2cm$, nest depth $9.8{\pm}3.1cm$, nest cup diameter $11.2{\pm}1.5cm$ and nest cup depth $3.27{\pm}0.80cm$. Nests were attached to cemented walls (44.9%), wooden materials (23.1%), bricks (21.8%) and lighting (6.4%). The average clutch size was 4.5 and ranged 2~5. Mean egg length was $18.23{\pm}0.73mm$, breadth $13.11{\pm}0.25mm$, volume $1.60{\pm}0.11cm^3$, shape index $1.39{\pm}0.05$ and weight $1.69{\pm}0.15g$. Hatching and fledgling success rate were 89.1% and 84.5%. Main causes for reproductive failures were unhatched eggs, predation, nest destruction and desertion. These results are expected to be widely used as data for habitat preservation and species management of barn swallows.

• Journal of the Korean Society of Hazard Mitigation
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• v.8 no.1
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• pp.1-7
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• 2008

When historical or cultural buildings need to be repaired or reinforced, the changes of original features should be minimized, and the strengths of structures should be improved. Among the existing methods to reinforce historical wood structures, the carbon fiber reinforcement polymer (CFRP) installation method is one of the best ones to achieve the afore-mentioned requirements. Therefore, this study aims at investigating the reinforcing effects and failure modes of timber beams reinforced with the inserted CFRP, a part of roof trusses in modern wood structures, and at providing the fundamental test data to estimate the CFRP rein-forced timber beam in the application of this reinforcing method. The primary parameters in this study were the layout and amount of CFRP. It was observed that, when $0.3{\sim}0.7%$ of CFRP were installed, the strengths of reinforced timber beams increased up to 173% compared to its original strength, but their strengthening effects were heavily influenced by the characteristics of timber such as burls. In order to improve the applicability of this strengthening method, fundamental understandings on the characteristics of wood would be necessary, and there would be in need of researches on the non-destructive test for wood structures as well.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.2
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• pp.1450-1460
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• 2015

This study is to analyze various methods of block design elements applied in the recent apartment housing design competitions for Sejong city. It is expected to find the new design trend and good design characteristics of apartment building forms to use as the basic data of apartment housing design, because it is a case study on the ambitious design competition of the city that many major architectural firms in Korea entered and eager to propose new ideas. The results of this study are following : (1) The forms of slab block are classified into 8 types(the best applying one is ㄱ type). The forms of point block are classified into 9 types(the best applying ones are ㅁ, L and - type). (2) For the shapes of core, the forms of opposite core are classified into 6 types, the forms of parallel core are 3 types. (3) The forms of roof are classified into 4 types. The flat type is applied to 95 percent of the total cases. (4) The shapes of block mass are classified into 5 types(the best applying ones are general and void type), facade forms are 3 types(the best applying one is horizontal division type).

• Transactions of the Korean Society of Mechanical Engineers B
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• v.41 no.2
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• pp.97-107
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• 2017

This study is the second investigation on the steady flow characteristics of an SI engine with a semi-edge combustion chamber as a function of the port shape with varying evaluation positions. For this purpose, the planar velocity profiles were measured from 1.75B, 1.75 times of bore position apart from the bottom of head, to 6.00B positions using particle - image velocimetry. The flow patterns were examined with both a straight and a helical port. The velocity profiles, streamlines, and centers of swirl were almost the same at the same valve lift regardless of the measuring position, which is quite different from the case of the pent-roof combustion chamber. All the eccentricity values of the straight port were out of distortion criterion 0.15 through the lifts and the position. However, the values of the helical port exceeded the distortion criterion by up to 4 mm lift, but decreased rapidly above the 3.00B position and the 5 mm lift. There always existed a relative offset effect in the evaluation of the swirl coefficient using the PIV method due to the difference of the ideal impulse swirl meter velocity profile assumption, except for the cylinder-center-base estimation that was below 4 mm of the straight port. Finally, it was concluded that taking the center as an evaluation basis and the assumption about the axial velocity profile did not have any qualitative effect on swirl evaluation, but affected the value owing to the detailed profile.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.37 no.1
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• pp.9-18
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• 2019

The intensity and the number of days of high temperature occurrence are also high and record heat occurred. In addition, the global warming phenomenon is intensifying globally, and especially in South Korea, the urban heat island phenomenon is also occurring due to rapid urbanization due to rapid industrial development. As the temperature of the city rises, it causes problems such as the comfort of the residential living and the cooling load. In this study, the cool roof performance is evaluated according to the roof color to reduce these problems. Unlike previous studies, UAV(Unmanned Aerial Vehicle) thermal infrared camera was used to obtain the surface temperature (white, grey, green, blue, brown, black) according to the rooftop color by remote sensing technique. As a result, the surface temperature of white color was $11{\sim}20^{\circ}C$ lower than other colors. Also air conditioning temperature of white color was $1.5{\sim}4.4^{\circ}C$ lower than other colors and the digital thermometer of white color was about $1.5{\sim}3.5^{\circ}C$ lower than other colors. It was confirmed that the white cool roof performance is the best, and the UAV and the thermal infrared camera can confirm the cool roof performa.

• Korean Journal of Heritage: History & Science
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• v.43 no.1
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• pp.212-235
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• 2010

The purpose of this study is to examine the characteristics of the location and the spatial composition of Uireung that is located in Seokgwan-dong, Seongbuk-gu, Seoul, in order to understand the landscape architectural characteristics. The results are as follows. First, Uireung is 6.4km from Changdeokgung Palace and 5.5km from Heunginjimun Gate. It did not violate the distance standard (40km) for the royal tombs according to Joseon Dynasty Neung-won Myo-je. Second, Uireung is in harmony with the nature and shows the authoritative characteristics of the royal authority through the spatial composition and rank(Entrance Area, Ceremonial Area, Burial Area). Third, there are burial mound, stone sheep, stone tiger, stone table, stone watch pillars in the upper platform, and stone civil official, stone horse, stone lantern in the middle platform, and stone military official, stone horse in the lower platform, and T-shape shrine, worship road in the ceremonial area. There is no pond and a tomb keeper residence, but the position, size, and form can be approximated through historical research materials. There are a colony of pine trees around the burial mound and 64 species of trees such as pine tree, zelcova tree, and fir tree below the burial mound.

• Korean Journal of Heritage: History & Science
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• v.49 no.1
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• pp.68-83
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• 2016

Pan-jang(板墻) has become the lost facility, and the examples of its original form can be found no more due to its variable material characteristics. In order to study panjang as a lost facility, the following are needed: - To bring to light its usage and examples. - To investigate its components and structure. Panjang refers to the wall made of wooden plate and is classified as a special wall according to its material characteristics. In addition, Chinese mokyeongbyuk(木影壁) and Japanese panbyeong(板?) are similar to Korean panjang in terms of the materials, but there are clear differences in their structures. Panjang was also transformed into various types according to their materials or forms. As the wooden elements of panjang, sinbang(信防), pillars, do-ri(道里), jungbang(中枋), inbang(引枋), parn(板), dae(帶), choyeop(草葉), bangyeon(方椽), gaeparn(蓋板), pyeonggodae(平高臺), and yeonharm(椽檻) were selectively used, and they are similar, in particular, to the components of ilgakmoon(一角門). The stylobate of panjang is largely classified into three according to the kinds and structures of the wooden elements; and its frame into two according to whether sanginbang(上引枋) is used or not. The materials for the roof area include planks(蓋板) and tiles and have the distinct structural differences according to each material.

• The Journal of the Korea Contents Association
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• v.22 no.3
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• pp.322-330
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• 2022

With the development of media, modern times are actively exchanging cultures and information around the world. Therefore, product development using traditional material, which are Korean cultural heritages, can be said to be another medium that can promote our unique culture to the world. Therefore, this study attempted to develop a product suitable for the modern lifestyle that combines tradition and modernity by investigating and analyzing Korean roof tiles and applying the formative elements identified as a result of the study. Among the types of roof tiles, a Sumaksai, which is located on the front of the roof and stands out for decoration, was selected as the subject of the study, and it was developed by combining it with lighting and plates as an item for modern people seeking a life full of personality. In product development, we tried to express the traditional style as it is by making the most of the elements of the Sumaksai, and the lotus pattern, which was most commonly used in each era when roof tiles were made, was simplified and applied to the product. As the products developed in this way are used in our daily lives, we hope that users' interest in ours will increase, and that the development of various products through research on traditional material can be activated as a way to spread our culture around the world.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.41 no.1
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• pp.21-34
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• 2023

This study identified the materials and construction methods of 'Old Wall' in 13 villages which were designated as National Registered Cultural Heritage at the time of designation and examined the their structural changes based on field survey. The results are as follows: First, the 'Old Wall' consisted of 10 Soil-Stone Wall and 5 Stone Wall. At the time of designation, Stone Wall, which was built irregularly by dry-construction of natural stones, is similar in shape, but Soil-Stone Wall showed difference by the construction method of making used stones, joints, and faces. Second, the study extracted the changes of 'Old Wall' by repair and examined the changes of construction methods as well as the substitution and addition of materials of structure. The wall-roof was built with cement roof-tile and asbestos slate which have the advantage improve durability and cost-effectiveness. In addition, tile-mouth soil was added to korean traditional roof-tile to prevent rainwater from flowing in. Besides, to improve constructional convenience, the natural stone of the wall-body was replaced with blast stone, float stone and cut stone. Cement block, cement brick and cement mortar were frequently used to repair as well. As Soil-Stone Wall was transformed from irregular pattern-construction to comb pattern-construction and wet-construction was changed to dry-construction, it caused landscape and structural problems. Also, the layer of cement mortar applied to wall-foundation blocked the flow of rainwater that was induced by dry-construction of natural stones. Third, the study regarded that the problem with the repair of 'Old Wall' may occur as it is located in living space, because the owner of the wall could repair for the minor damages without technical knowledge. In addition, it is difficult for repair companies in charge of maintenance of Cultural Heritage to supply local materials, and it is differential construction specifications are not applied.