• Journal of Korean Tunnelling and Underground Space Association
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• v.9 no.2
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• pp.109-120
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• 2007

Auxiliary support systems such as the reinforced protective umbrella method have been applied before tunnel excavation to increase ground stiffness and to prevent the large deformation. However, determination procedure of geotechnical parameters along the construction sequence contains various errors. This study suggests a method to characterize the time-dependent behavior of pre-reinforced zones around the tunnel using elastic waves. Experimental results show that shear strength as well as elastic wave velocities increase with the curing time. Shear strength and strength parameters can be uniquely correlated to elastic wave velocities. Obtained results from the laboratory tests are applied to numerical simulation of tunnel considering its construction sequences. Based on numerical analysis, initial installation part of pre-reinforcement and portal of tunnel are critical for tunnel stability. Result of the time-dependent condition is similar to the results of for $1{\sim}2$ days of the constant time conditions. Finally, suggested simple analysis method combining experimental and numerical procedure which considering time-dependent behavior of pre-reinforced zone on tunnel would provide reliable and reasonable design and analysis for tunnel.

• Journal of Digital Convergence
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• v.11 no.10
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• pp.59-69
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• 2013

20s country employment rate to 57% in the last four years, is staying low. College graduates in the 25-29 year old crowd real unemployment rate is over 20% youth unemployment, the analysis problem is serious enough. Accordingly, activation of Cooperation, which addresses the issues of these countries now being recognized as the primary means, and in the future, government policy and national indicators to be given more attention and support seems clear. Government from 2012 'Cooperation Development Project leading universities' (LINC: Leaders in INdustry-university Cooperation) by promoting companies that require manpower, actual research and development and technology transfer to enable the University - Industry - between research institutions based on organic correlated with local universities and industrial growth model for the creation of a variety of leading industry cooperation. has to diffuse. This background, the aim of this study at the University of excavation site close-type talent. Fostering curriculum development are essential to the field on the form will close. In this study, major department (Department) conducted by major research based on the results of the curriculum needs to spread the field for Cooperation closely analyze the curriculum and Annual type, domain-specific promotion measures proposed.

• Journal of Korean Tunnelling and Underground Space Association
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• v.23 no.5
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• pp.325-337
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• 2021

On the road and rail tunnels, the evacuation pathway and facilities such as smoke-control and fire suppression system are essential in tunnel fire. In the long twin tunnels, the cross-connection tunnel is usually designed to evacuate from the tunnel where the fire broke out to the other tunnel. In twin shield tunnels, the segment lining has to be demolished to construct the cross-connection tunnel. Considering the modern shield TBM is mostly the closed chamber type, the exposure of underground soil induced by removal of steel segment lining is the most danger construction step in the shield tunnel construction. This case study introduces the excavation method using the thrust of large steel pipe and reviews the measured data after the construction. The large steel pipe thrust method for the cross-connection tunnel can stabilize the excavated face with the two mechanisms. Firstly, the soil in front of excavated face is cylindrically pre-supported by the large steel pipe. Secondly, the excavated face is supported by the plugging effect caused by the soil pressed into the steel pipe. It was reviewed that the large steel pipe thrust method in the cross-connection tunnel is enough to secure the construct ability and stability in soil from the measurement results about the deformation and stress of steel pipe.

• Korean Journal of Heritage: History & Science
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• v.48 no.3
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• pp.154-165
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• 2015

Common issues in research and policy on cultural heritage can be extracted among Eurasian countries although countries in the region show different colors of policies and studies. Among them one thing peculiar to Central Asian countries is that in general they do not have well delineated laws and regulations on the protection of cultural heritage. It may be because they had no enough time and experience to legislate and implement relevant laws and regulations ever since they got independence. Research on cultural heritage in Central Asian countries is often made in cooperation with foreign institutions. As shown in archaeological excavation projects in Central Asian countries, cooperative projects exceed noncooperative ones in terms of size and longevity. UNESCO, through its projects on the Serial and Transboundary World Heritage Nomination of the Silk Roads in Central Asia, also supports countries in Central Asia and others along the Silk Road in order to facilitate inclusion of their cultural heritages in the Tentative List of the World Heritage. With regard to activities on the protection of cultural heritage, while respective countries in Central Asia have made good efforts, they could not produce effective outcomes due to short of budget and specialized manpower. They have rich resources of cultural and documentary heritage but their registered heritages on the UNESCO's World Heritage List and Memory of the World are under-represented because of short of technology and experience among other things. A new trend in cultural heritage studies that combined cultural heritage with tourism has merged in recent years. While some critics have raised some negative questions, this new fashion became popular and will continue with the support of governments of Silk Road countries. In conclusion, Korean institutions are further encouraged to organize cooperative networks for research and policy with respective Eurasian countries.

• Journal of Korean Tunnelling and Underground Space Association
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• v.21 no.3
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• pp.363-375
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• 2019

Since the double-deck tunnel is deeply constructed in the city, it is necessary to secure the installation space of air supply and exhaust, escape passage stairs, elevator, distribution facilities and connection tunnels in the vertical shaft for the double-deck tunnel. Also, in order to minimize the effect of construction on adjacent area, it is necessary to construct the concrete structures at high speed in vertical shaft after tunnel excavation. Therefore, the slabs and the stairs in vertical shaft are needed to be constructed using precast concrete, and the rapid construction techniques of bracket for supporting the inner precast structure are needed. The bracket installation methods include cast-in-place concrete, precast concrete and steel. In this study, the improvement of the steel brackets with good economical efficiency and good workability was carried out in consideration of the improvement of the construction speed. We have developed a new bracket that is optimized through bracket shape improvement, anchor bolt position adjustment and quantity optimization. As a result of the structural performance test, it was confirmed that the required load supporting capacity was secured. As a result of structural performance test for bar type anchor bolt and bent anchor anchor bolt, it was confirmed that the required load carrying capacity was secured and that the load bearing capacity of bent anchor bolt was large.

• International conference on construction engineering and project management
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• 2022.06a
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• pp.1250-1251
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• 2022

Measuring management is an important part of preventing the collapse of retaining walls in advance by evaluating their stability with a variety of measuring instruments. The current work of measuring management requires considerable human and material resources since measurement companies need to install measuring instruments at various places on the retaining wall and visit the construction site to collect measurement data and evaluate the stability of the retaining wall. It was investigated that the applicability of the current work of measuring management is poor at small and medium-sized urban construction sites(excavation depth<10m) where measuring management is not essential. Therefore, the purpose of this study is to develop a laser sensor-based hardware to support the wall displacement measurements and their control software applicable to small and medium-sized urban construction sites. The 2D lidar sensor, which is more economical than a 3D laser scanner, is applied as element technology. Additionally, the hardware is mounted on the corner strut of the retaining wall, and it collects point cloud data of the retaining wall by rotating the 2D lidar sensor 360° through a servo motor. Point cloud data collected from the hardware can be transmitted through Wi-Fi to a displacement analysis device (notebook). The hardware control software is designed to control the 2D lidar sensor and servo motor in the displacement analysis device by remote access. The process of analyzing the displacement of a retaining wall using the developed hardware and software is as follows: the construction site manager uses the displacement analysis device to 1)collect the initial point cloud data, and after a certain period 2)comparative point cloud data is collected, and 3)the distance between the initial point and comparison point cloud data is calculated in order. As a result of performing an indoor experiment, the analyses show that a displacement of approximately 15 mm can be identified. In the future, the integrated system of the hardware designed here, and the displacement analysis software to be developed can be applied to small and medium-sized urban construction sites through several field experiments. Therefore, effective management of the displacement of the retaining wall is possible in comparison with the current measuring management work in terms of ease of installation, dismantlement, displacement measurement, and economic feasibility.

• Journal of Digital Convergence
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• v.21 no.3
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• pp.49-62
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• 2023

Due to social and cultural changes and the growth of aging people living as a single because of aging, lonely deaths are steadily increasing, and each local government has begun to define them as a social problem. The legal basis began to be established. In order to explore policy measures to prevent lonely deaths, this study examined cases of lonely death prevention policies using smart digital information technology (AI, IOT), which is being promoted by Daegu Metropolitan City to promote non-face-to-face policies to prevent lonely deaths. Policies related to lonely deaths are divided into two axes: lonely death prevention projects and post-excavation support projects. In order to operate these businesses efficiently, the provision of non-face-to-face services through artificial intelligence and the Internet of Things is recognized as a new service delivery system, so the importance and necessity of non-face-to-face services is increasing. It is time that multifaceted changes and preparations are needed, such as establishing a system to expand the non-face-to-face industry at the national level. In order to respond to another national disaster situation in the future, the non-face-to-face smart care system is being expanded in various welfare policies such as preventing lonely deaths. It will have to be activated.

• (The) Research of the performance art and culture
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• no.35
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• pp.405-439
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• 2017

In this article, I suggest issues and tasks in transmission of Gyeonggi Province folk songs after thorough study of designation of Gyeonggi Province folk songs as intangible cultural asset, reproduction and transmission. Intangible cultural assets are classified into seasonal playing and songs. Originally, category or extension of folk songs is above mere songs and it also embraces personal lives as well as village communities. Intangible assets of folk songs are folk art, group events and non-stage events at the same time based on tradition, history, uniqueness, characters of field value. Gyeonggi Province has 9 intangible assets now because of the revocation of several assets (All Gyeonggi Province, Hwasung, Gwacheon) within five years after initial designation of 13 assets in 1998. They are mostly distributed in the north Gyeonggi region where is close to the DMZ and delay in development seems to have enabled the preservation. Most of the intangible cultural assets are farming songs and weeding which show characteristics of Gyeonggi Province. Most of the designees are who performed excavation, recovery, excluding a few cases without designees on designation, and almost all the designee passed away. Number of cases have been revoked because transmission was not completed or some cases were transmitted to groups rather than specific designees. Subscription concert, the biggest and most representative event, is performed once a year with all of the 9 intangible cultural assets in the original complete forms of the designation. Intangible cultural assets are classified into seasonal playing and songs. In general, current performance of the intangible cultural assets and folk songs are same as the originally designated forms and are not in varied forms other than folk songs like songs for rice-planting and weeding. Funeral songs are transmitted in Yangju and Yangpyeong. In terms of the operation, preservation societies having training centers have been performing more constant activities for preservation including lecture, performance and transmission. Members are quite aged and the societies are suffering from lack of support fund for reproduction and transmission. Problems in reproduction and tasks for the transmission I would like to suggest are like followings. First, preservation and value of the cultural assets. Second, new understanding of designation and revocation of the intangible cultural assets. Third, record of performance and sound source. Fourth, liaison with local communities. Fifth, organization of professional resources and establishment of systematic support and management.

• Journal of Korean Tunnelling and Underground Space Association
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• v.20 no.3
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• pp.593-608
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• 2018

If a problem occurs in the strut during the construction of the braced wall, they may cause excessive deformation of the braced wall. Therefore, in this study, the behavior of the braced wall and existing tunnel adjacent to excavation were investigated assuming that the support function of strut is lost during construction process. For this purpose, a series of model test was performed. As a result of the study, the earth pressure in the ground behind wall was rearranged due to the deformation of the braced wall, and the ground displacements caused the deformation of adjacent tunnels. When the struts located on the nearest side wall from the tunnel were removed, the deformation of the braced wall and the tunnel deformation were the largest. The magnitude of transferred earth pressure depended on the location of tunnel. The increase of the cover depth of tunnel from 0.65D to 2.65D caused the increase of the earth pressure by 25.6%. As the distance between braced wall and tunnel was increased from 0.5D to 1.0D, the transferred earth pressure increased by 16% on average. Horizontal displacements of braced wall by the removal of the strut tended to concentrate around the removed struts, and the horizontal displacement increased as the strut removal position is lowered. The tunnel displacement was maximum, when the cover depth of tunnel was 1.15D and the horizontal distance between braced wall and the side of tunnel was 0.5D. The minimal displacement occurred, when the cover depth of tunnel was 2.65D and the horizontal distance between braced wall and the side of tunnel was 1.0D. The difference between the maximum displacement and the minimum displacement was about 2 times, and the displacement was considered to be the largest when it was in the range of 1.15D to 1.65D and the horizontal distance of 0.5D.

• Journal of architectural history
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• v.19 no.3
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• pp.7-29
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• 2010

The form of the Wangheungsa Temple's wooden pagoda site is that of the traditional form of the wooden pagodas constructed during the Baekjae Period. Likewise, it is an important ruin for conducting research on the form and type of the wooden pagodas constructed during the Baekjae Period. In particular, the method used for the installation of the central pillar's cornerstone is a new technique. The purpose of this research is to restore the ruin of the Wangheungsa Temple's wooden pagoda of the Baekjae Period that remains at the Wangheungsa Temple's wooden pagoda site. Until now, research conducted on the wooden pagoda took place mostly centered on the Hwangryongsa Temple's wooden pagoda. Meanwhile, the reality concerning Baekjae's wooden pagoda is one in which there were not many parallel cases pertain to the design for restoration. This research paper wants to conduct academic examination of the Wangheungsa Temple's wooden pagoda to organize the intention of design and design process in a simple manner. This research included review of the Baekjae Period's wooden pagoda related ruins and the review of the existing wooden pagoda ruin to analyze the wooden pagoda construction technique of the era. Then, current status of the Wangheungsa Temple's wooden pagoda site is identified to define the characteristics of the wooden pagoda, and to set up the layout format and the measure to estimate the size of the wooden pagoda in order to design each part. Ultimately, techniques and formats used for the restoration of the wooden pagoda were aligned with the wooden pagoda of the Baekjae Period. Basically, conditions that can be traced from the current status of the Wangheungsa Temple site excavation using the primary standards as the standard. Wangheungsa Temple's wooden pagoda was designed into the wooden pagoda of the Baekjae's prosperity phase. The plane was formed into $3{\times}3$ compartments to design into three tier pagoda. The height was decided by factoring in the distance between the East-West corridors, size of the compartment in the middle, and the view that is visible from above the terrace when entering into the waterway. Basically, the origin of the wooden structure format is based on the Goguryeo style, but also the linkage with China's southern regional styles and Japan's ancient wooden pagoda methods was factored in. As for the format of the central pillar, it looks as if the column that was erected after digging the ground was used when setting up the columns in the beginning. During the actual construction work of the wooden pagoda, central pillar looks as if it was erected by setting up the cornerstone on the ground. The reason that the reclaimed part of pillar that use the underground central cornerstone as the support was not utilized, was because the Eccentric Load of the central pillar's cornerstone was factored in the state of the layers of soil piled up one layer at a time that is repeated with the yellow clay and sandy clay and the yellow clay that were formed separately with the $80cm{\times}80cm$ angle at the upper part of the central pillar's cornerstone was factored in as well. Thus, it was presumed that the central pillar was erected in the actual design using the ground style format. It is possible to presume the cases in which the reclaimed part of pillar were used when constructed for the first time, but in which central pillar was installed later on, after the supplementary materials of the underground column is corroded. In this case, however, technique in which soil is piled up one layer at a time to lay down the foundation of a building structure cannot be the method used in that period, and the reclamation cannot fill up using the $80cm{\times}80cm$ angle. Thus, it was presumed that the layers of soil for building structure's foundation was solidified properly on top of the central pillar's cornerstone when the first wooden pagoda construction work was taking place, and that the ground style central pillar was erected on its upper part by placing the cornerstone once again. Wangheungsa Temple's wooden pagoda is significant from the structure development aspect of the Korean wooden pagodas along with the Hwangryongsa Temple's wooden pagoda. Wangheungsa Temple's wooden pagoda construction technique which was developed during the prosperity phase of the Baekjae Period is presumed to have served as a role model for the construction of the Iksan Mireuksa Temple's wooden pagoda and Hwangryongsa Temple's wooden pagoda. With the plan to complement the work further by excavating more, the basic wooden pagoda model was set up for this research. Wangheungsa Temple's wooden pagoda was constructed as at the Baekjae Kingdom wide initiative, and it was the starting point for the construction of superb pagoda using state of the art construction techniques of the era during the Baekjae's prosperous years, amidst the utmost interest of all the Baekjae populace. Starting out from its inherent nature of enshrining Sakyamuni's ashes, it served as the model that represented the unity of all the Baekjae populace and the spirit of the Baekjae people. It interpreted these in the most mature manner on the Korean peninsula at the time.