• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.21 no.5
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• pp.135-140
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• 2021

In this paper, we propose an on-line mechanism that simultaneously detects cracks and profiling pavement blocks to detect the displacement of ground surface adjacent to the excavation in the urban area. The proposed method utilizes a 2D laser to profile the information about pavement blocks including the depth and distance among them. In particular, it is designed to enable the detection of cracks and portholes at runtime. For the experiment, real data was collected through Gocator, and trainng was carried out using Faster R-CNN. The performance evaluation shows that our detection precision and recall are more than 90% and the pavement blocks are profiled at the same time. Our proposed mechanism can be used for monitoring management to quantitatively detect the level of excavation risk before a large-scale ground collapse occurs.

• Journal of Conservation Science
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• v.37 no.4
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• pp.312-321
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• 2021

Underwater archaeology relies heavily on photography and video image recording during surveillances and excavations like ordinary archaeological studies on land. All underwater images suffer poor image quality and distortions due to poor visibility, low contrast and blur, caused by differences in refractive indices of water and air, properties of selected lenses and shapes of viewports. In the Yellow Sea (between mainland China and the Korean peninsula), the visibility underwater is far less than 1 m, typically in the range of 30 cm to 50 cm, on even a clear day, due to very high turbidity. For photographing 1 m x 1 m grids underwater, a very wide view angle (180°) fisheye lens with an 8 mm focal length is intentionally used despite unwanted severe barrel-shaped image distortion, even with a dome port camera housing. It is very difficult to map wide underwater archaeological excavation sites by combining severely distorted images. Development of practical compensation methods for distorted underwater images acquired through the fisheye lens is strongly desired. In this study, the source of image distortion in underwater photography is investigated. We have identified the source of image distortion as the mismatching, in optical axis and focal points, between dome port housing and fisheye lens. A practical image distortion compensation method, using customized image processing software, was explored and verified using archived underwater excavation images for effectiveness in underwater archaeological applications. To minimize unusable area due to severe distortion after distortion compensation, practical underwater photography guidelines are suggested.

• The Journal of Fisheries Business Administration
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• v.50 no.2
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• pp.1-21
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• 2019

This study is to excavate superior fishing communities by applying the Ostrom (1990)'s principles of sustainable and successful use of common goods. Ostrom(1990)'s principles are (1) clearly defined boundaries (2) congruence between appropriation and provision rules and local conditions, (3) collective choice arrangements (4) monitoring (5) graduated sanctions (6) conflict-resolution mechanism (7) recognition of rights to organize by external government authorities (8) nested enterprises. The survey was carried out under the individual interview method of 15 fishing village members in 32 fishing communities with the government's fishery environment improvement and fishery creation projects. The total effective samples are 477. These data were analyzed. The analysis result shows that 24 fishing villages are selected among the 32 fishing communities in the samples, including Nanji, Sanghwang, Songseok, Sinshido, Jukyo, Jinsan, Changli, Pado, Beopsan, Rahyang, Palbong, Woongdo, Daehwang, Sapsi, Chido, Jinri, Daeri, Songgak, Joongwang, Ojii, Doripo, Doseong, Mongsan 1ri and Songnim as superior fishing villages. The results of this study have limitation that may vary depending on the rigor of the criteria in the process of deriving good fishing communities. Despite this limitation, this study has expanded existing research focused on validating the theoretical applicability of the framework through case analysis of specific fishing communities to objectively and quantitatively to many fishing communities. The results of this study are expected to contribute to the creation of conditions in which fishermen can continue to manage their fishing grounds and stand on their own feet by presenting the framework and principles for developing desirable fishing village models for the continued use of mudflat shells grounds as the common goods.

• Journal of the Korean Geotechnical Society
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• v.35 no.9
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• pp.37-45
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• 2019

Quick identification of the condition of tunnel face and optimized determination of support patterns during tunnel excavation in underground construction projects help engineers prevent tunnel collapse and safely excavate tunnels. This study investigates a CNN technique for quick determination of rock quality classification depending on the condition of tunnel face, and presents the procedure for rock quality classification using a deep learning technique and the improved method for accurate prediction. The VGG16 model developed by tens of thousands prestudied images was used for deep learning, and 1,469 tunnel face images were used to classify the five types of rock quality condition. In this study, the prediction accuracy using this technique was up to 83.9%. It is expected that this technique can be used for an error-minimizing rock quality classification system not depending on experienced professionals in rock quality rating.

• Journal of the Korean Geotechnical Society
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• v.37 no.9
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• pp.37-50
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• 2021

Recently, due to the expansion of urban infrastructure using underground spaces in urban areas, many adjacent constructions and excavations have been made carried out between existing facilities, and complaints related to the stability of existing facilities due to close construction have become significant issues. In this study, it was closely reviewed for the existing metro tunnel structure in the new Dongbuk urban metro railway to determine the behavioral characteristics of tunnel structure according to adjacent tunnel construction. Also, it was analysed the evaluation of the safety zone and excavation method for metro tunnel structure. And after a detailed damage assessment, track irregularities and structural calculation by using a numerical analysis, stability of the metro tunnel structure according to nearby tunnel excavation was evaluated to be secured for safety. This study is expected to be applied as practical reference to review the evaluation of safety effects of existing tunnel structure and buildings according to adjacent construction in complex deep urban tunnelling.

• Journal of the Korean GEO-environmental Society
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• v.12 no.2
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• pp.45-53
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• 2011

Soil nailing method was often designed by the slope stability analysis based on limit equilibrium. However, in the case of shorten length of nails, although the calculated factor of safety is within the design factor of safety, the horizontal displacement of soil nailed walls occurred above the allowable limit. In this study, relationship between the load and factor of safety, and relationship between the load and displacement ratio based on the test results were analysed. From the analysed results, the relationship between factor of safety and displacement ratio was estimated. For the mobilized horizontal displacement of the walls within the serviceability limit corresponding to the displacement of less than 0.3% displacement ratio, the calculated factor of safety by limit equilibrium analysis had to satisfy above 1.35. Also, although the minimum factor of safety is estimated above 1.35, the maximum horizontal displacement is often mobilized above 0.3% of excavation height. Therefore, it is necessary to perform the numerical analysis of soil nailed walls in the case of low shear strength or high excavation.

• Journal of the Korean Geotechnical Society
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• v.37 no.3
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• pp.5-17
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• 2021

This study aims to investigate the causes and countermeasures for the occurrence of tension cracks in the slope of the rock mass of heavy equipment for road construction. Electric resistivity survey was performed to investigate the expandable tensile crack range. As a result of examining the distribution of soft zones in the rock mass, a low specific resistance zone was found at the bottom of the access road where tensile cracks occurred. It was confirmed that a low resistivity zone was distributed near the top of the excavation slope. Therefore, reinforcements was performed by determining the location of the possible tensile crack as the top of the excavation slope. Two rows of reinforced piles and anchors were proposed as a reinforcement method, and the slope stability analysis showed that the allowable safety factor was satisfied after reinforcements.

• Journal of architectural history
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• v.31 no.1
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• pp.7-17
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• 2022

The purpose of this thesis is to understand the shape of The Sijeon (Licensed-Markets) established around the Jongno and Namdaemun-ro Avenues in Hanyang during the Joseon Dynasty in the 19th and 20th centuries and then to examine the relationship with the urban structures of Hanyang City. By investigating the excavation results of the Cheongjin and Gongpyeong areas, drawings, photos, and documentary records related to the city, this study classified the building types in the Jonggak area. As a result, since the 19th century, the basic form of Sijeon with 2 Gan(間, bay) in the front facade and 3 Gan(間) on the side, in other words, 5M in the front and 8M in the side was arranged in parallel, and it was a type with a corridor-type courtyard inside. The inner sides of Jongno Avenue had an atypical flat shape that suited the more free lot, and a courtyard-type plan with a single entrance was also confirmed in the one or two Bang(房, district). This study reflected the operation method of the Sijeon buildings b between the one unit and the other units, which affected the internal spatial structures, and it found that the size and style of the Sijeon buildings were closely relevant to the size of the lots near Jongno Avenue.

• Geomechanics and Engineering
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• v.36 no.1
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• pp.51-69
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• 2024

Currently, composite lining mountain tunnels in China are generally classified based on the [BQ] method for the surrounding rock grade. Increasingly, tunnel field construction is replicated indoors for scale down model tests. However, the development of analogous materials for model tests of composite lining tunnels with different surrounding rock grades is still unclear. In this study, typical Class III and V surrounding rock analogous materials and corresponding composite lining support materials were developed. The whole processes of excavation-support dynamics of the mountain tunnels were simulated. Data on the variation of deformations, contact pressures and strains on the surrounding rock were obtained. Finally, a comparative analysis between model tests and numerical simulations was performed to verify the rationality of analogous material development. The following useful conclusions were obtained by analyzing the data from the tests. The main analogous materials of Class III surrounding rock are barite powder, high-strength gypsum and quartz sand with fly ash, quartz sand, anhydrous ethanol and rosin for Class V surrounding rock. Analogous materials for rockbolts, steel arches are replaced by aluminum bar and iron bar respectively with both shotcrete and secondary lining corresponding to gypsum and water. In addition, load release rate of Class V surrounding rock should be less than Class III surrounding rock. The fenestration level had large influence on the load sharing ratio of the secondary lining, with a difference of more than 30%, while the influence of the support time was smaller. The Sharing ratios of secondary lining in Class III surrounding rock do not exceed 12%, while those of Class V surrounding rock exceed 40%. The overall difference between the results of model tests and numerical simulations is small, which verifies the feasibility of similar material development in this study.

• Journal of the Korea Fashion and Costume Design Association
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• v.25 no.4
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• pp.107-122
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• 2023

This study analyzed the style, dimensions, fabric patterns, colors, and fabrics of a traditional Chinese women's dress from the Zhou Dynasty, and reconstructed it in the form of a virtual garment using 3D CLO. Based on ancient flat image data and three-dimensional portrait data, who wore them, how they were worn, and how they were coordinated was analyzed. In order to analyze the size and pattern of the straight Ju Chines dress, data from the excavation report and the tomb owner's anthropometric measurements were combined to infer the wearing condition and organize the sculptural features. Dimensional analysis was carried out using a well-preserved small-scale woven cotton cloth as a restoration model, and the horizontal and vertical dimensions were reasonably estimated using the shape proportioning method. The analysis of the colors and patterns of the fabrics was based on the colors and patterns of the fabrics excavated from Masan Tomb No. 1 during the Eastern Zhou, Qin, and Han periods. Finally, a virtual model was created using data from the excavation report and the age and height information of the owner of the excavated robe, and the pose and size of the virtual model were determined using 3D CLO. Based on the previous research data, the garment was virtually sewn and simulated. The shape, pressure, and strain of the garment in different postures was also compared. Through the research direction of pattern and 3D restoration, this research maximizes the restoration of Chinese traditional women's dress and presents it in a more intuitive, comprehensive, and vivid way.