• Journal of the Korean Geosynthetics Society
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• v.20 no.4
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• pp.85-93
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• 2021

The seventy percentage of Korean Peninsular is covered by the mountainous area, and the depth of west sea and south sea is relatively shallow. Therefore, a large scale land reclamation from the sea has been implemented for the construction of industrial complex, residental area, and port and airport facilities. The common problem of reclaimed land is consisted of soft ground, and hence it has low load bearing capacity as well as excessive settlement upon loading on the ground surface. The hollow concrete block has been used to reinforce the loose and soft foundation soil where the medium-high apartment or one-story industrial building is being planned to be built. Recently the earthquakes with the magnitude of 4.0~5.0 have been occurred in the west coastal and southeast coastal areas. Lee (2019) reported the advantages of hollow concrete block reinforced shallow foundation through the static laboratory bearing capacity tests. In this study, the dynamic behavior of hollow concrete block reinforced sandy ground with filling the crushed stone in the hollow space has been investigated by the means of shaking table test with the size of shaking table 1000 mm × 1000 mm. Three types of seismic wave, that is, Ofunato, Hachinohe, Artificial, and two different accelerations (0.154 g, 0.22 g) were applied in the shaking table tests. The horizontal displacement of structure which is situated right above the hollow concrete block reinforced ground was measured by using the LVDT. The relative density of soil ground are varied with 45%, 65%, and 85%, respectively, to investigate the effectiveness of reinforcement by hollow block and measured the magnitude of lateral movement, and compared with the limit value of 0.015h (Building Earthquake Code, 2019). Based on the results of shaking table test for hollow concrete block reinforced sandy ground, honeycell type hollow block gives a large interlocking force due to the filling of crushed stone in the hollow space as well as a great interface friction force by the confining pressure and punching resistance along the inside and outside of hollow concrete block. All these factors are contributed to reduce the great amount of horizontal displacement during the shaking table test. Finally, hollow concrete block reinforced sandy ground for shallow foundation is provided an outstanding reinforced method for medium-high building irrespective of seismic wave and moderate accelerations.

• Journal of Korean Tunnelling and Underground Space Association
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• v.23 no.3
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• pp.133-149
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• 2021

This study aims to report the behavioral mechanism of steel pipe reinforcement grouting, which is being actively used to ensure the stability of the excavation surface during tunnel excavation, based on measurements taken at the actual site. After using a 12 m steel pipe attached with a shape displacement meter and a strain gauge to reinforce the actual tunnel surface, behavioral characteristics were identified by analyzing the measured deformation and stress of the steel pipe. Taking into account that the steel pipes were overlapped every 6 m, the measured data up to 7 m of excavation were used. In addition, the behavioral characteristics of the steel pipe reinforcement according to the difference in strength were also examined by applying steel pipes with different allowable stresses (SGT275 and SGT550). As a result of analyzing the behavior of steel pipes for 7 hours after the first excavation for 1 m and before proceeding with the next excavation, the stress redistribution due to the arching effect caused by the excavation relaxation load was observed. As excavation proceeded by 1 m, the excavated section exhibited the greatest deformation during excavation of 4 to 6 m due to the stress distribution of the three-dimensional relaxation load, and deformation and stress were generated in the steel pipe installed in the ground ahead of the tunnel face. As a result of comparing the behavior of SGT275 steel pipe (yield strength 275 MPa) and SGT550 steel pipe (yield strength 550 MPa), the difference in the amount of deformation was up to 18 times and the stress was up to 12 times; the stronger the steel pipe, the better it was at responding to the relaxation load. In this study, the behavior mechanism of steel pipe reinforcement grouting in response to the arching effect due to the relaxation load was identified based on the measured data during the actual tunnel excavation, and the results were reported.

• Journal of the Korean Institute of Landscape Architecture
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• v.44 no.2
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• pp.25-36
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• 2016

This paper discusses the character of communication among participating stakeholders in the Improving Alley Landscapes in Residential Neighborhoods project. The participation of diverse stakeholders in conventional urban redevelopment is considered to delay and complicate the progress of a project. However, in urban regeneration, a field-oriented operating system and collaboration between diverse stakeholders is considered critical to building a sustainable community. A stakeholder is defined as "a person or organization that can influence decision-making or be influenced by it." This paper uses a case study to examine what types of stakeholders participate and what communicative processes and ideas are shared among them. Six neighborhoods were selected out of a total of 26 of Seoul's 2014 Improving Alley Landscapes project. This research was developed through interviews and a review of the literature. The character of communication among stakeholders in the case study is as follows. Firstly, the administration initiated the project but did not show leadership. This was caused by a gap in understanding about the project between city and borough administrations, Further, the city administration lacked experience with projects that placed an emphasis on fieldwork. Tongjand and Banjang, at ancillary institutions, acted as spokespersons and helped people in the community to understand the administrative process. However, because they led communication and used personal relationships to ensure they communicated effectively, the communication process had limits from the perspective of democratic process. Diverse stakeholders expressed their opinions in the public sphere and communicated about them using diverse media. Finally, experts produced the output, facilitated communication, and mediated in conflicts. Because new experts acted as facilitators and mediators, there was a great deal of trial and error. This project has particular significance: Seoul's city government deals with urban space rather than parks and green space, which are limited by boundaries; and whether "green" can be used for urban renovation was tested by several landscape architects, who sought to identify a new role in urban renovation, namely, the role of landscape and landscape architecture. However, the project has some limitations, including an insufficiently detailed project plan, a lack of common understanding among stakeholders, and a short timeframe. A number of stakeholders overcame these limitations to a certain degree. Officials of the Borough and the Dong managed the project and resolved civil complaints. Experts provided special information, and contributed to the design and construction of improvements.

• The Korean Journal of Air & Space Law and Policy
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• v.29 no.1
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• pp.3-32
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• 2014

Safety Management System is the aviation industry policy for while operating the aircraft, to ensure the safety crew, aircraft and passengers. For operating a safe aircraft, in order to establish the international technical standards, the International Civil Aviation Organization has established the Annex 19 of the Convention on International Civil Aviation. As a result, member country was supposed to be in accordance with the policy of the International Civil Aviation Organization, to accept the international standard of domestic air law. The South Korean government announced that it would promote active safety management strategy in primary aviation policy master plan of 2012. And, by integrating and state safety programmes(ssp) and safety management system(sms) for the safe management of Annex 19 is to enforce the policy on aviation safety standards. State safety programmes(ssp) is a system of activities for the aim of strengthening the safety and integrated management of the activities of government. State safety programmes(ssp) is important on the basis of the data of the risk information. Collecting aviation hazard information is necessary for efficient operation of the state safety programmes(ssp) Korean government must implement the strategy required to comply with aviation methods and standards of the International Civil Aviation Organization. Airlines, must strive to safety features for safety culture construction and improvement of safety management is realized. It is necessary to make regulations on the basis of the aviation practice, for aviation safety regulatory requirements, aviation safety should reflect the opinion of the aviation industry.

• Journal of Korean Tunnelling and Underground Space Association
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• v.25 no.6
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• pp.583-603
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• 2023

Recently, the advancement of mechanical tunnel boring machine (TBM) technology and the characteristics of subsea railway tunnels subjected to hydrostatic pressure have led to the widespread application of shield TBM methods in the design and construction of subsea railway tunnels. Subsea railway tunnels are exposed in a constant pore water pressure and are influenced by the amplification of seismic waves during earthquake. In particular, seismic loads acting on subsea railway tunnels under various ground conditions such as soft ground, soft soil-rock composite ground, and fractured zones can cause significant changes in tunnel displacement and stress, thereby affecting tunnel safety. Additionally, the dynamic response of the ground and tunnel varies based on seismic load parameters such as frequency characteristics, seismic waveform, and peak acceleration, adding complexity to the behavior of the ground-tunnel structure system. In this study, a finite difference method is employed to model the entire ground-tunnel structure system, considering hydrostatic pressure, for the investigation of dynamic behavior of subsea railway tunnel during earthquake. Since the key factors influencing the dynamic behavior during seismic events are ground conditions and seismic waves, six analysis cases are established based on virtual ground conditions: Case-1 with weathered soil, Case-2 with hard rock, Case-3 with a composite ground of soil and hard rock in the tunnel longitudinal direction, Case-4 with the tunnel passing through a narrow fault zone, Case-5 with a composite ground of soft soil and hard rock in the tunnel longitudinal direction, and Case-6 with the tunnel passing through a wide fractured zone. As a result, horizontal displacements due to earthquakes tend to increase with an increase in ground stiffness, however, the displacements tend to be restrained due to the confining effects of the ground and the rigid shield segments. On the contrary, peak compressive stress of segment significantly increases with weaker ground stiffness and the effects of displacement restrain contribute the increase of peak compressive stress of segment.

• Journal of the Korean Institute of Landscape Architecture
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• v.44 no.3
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• pp.13-24
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• 2016

What are the roles and functions of urban gardening created by citizens in Sujin 2-dong, Seongnam-si? This study has looked into urban gardening in everyday life in a bid to find possible solutions for sustainable urban regeneration. The paper has examined the types, functions, and characteristics of urban gardens in Sujin 2-dong, where the urban restoration project is in progress. This study has conducted primarily on-site inspections and interviews. The research findings are as follows. Most urban gardens in Sujin 2-dong have a vertical structure rather than a regular ground-based one due to lack of land. Six major locations of building a garden include the front of a building, rooftop, top of a gate, stairs, wall, and yard. Rooftop gardens are most common and are built mostly for production purposes. Due to architectural characteristics of this village, there are relatively many stair gardens built mostly for aesthetic purposes. The garden in front of a building has served multiple functions, including formation of entry, privacy protection, and prevention of unauthorized parking. Other than those, detached houses have quality urban gardens built with greater effort and care, while multi-household houses have seen a decrease of stair gardens and an increase of vertical gardens due to their comparatively limited space. By utilizing this research, we hope to show that it is important to understand the local's wisdom and voice for a sustainable urban environment as well as keep these findings in mind during the construction of new buildings. This study would be expected to be useful as primary research for urban gardening in everyday life and alternative ways of urban regeneration.

• Journal of Korean Tunnelling and Underground Space Association
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• v.19 no.1
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• pp.95-107
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• 2017

In this study, a preliminary study was undertaken for development of a tunnel incident automatic detection system based on a machine learning algorithm which is to detect a number of incidents taking place in tunnel in real time and also to be able to identify the type of incident. Two road sites where CCTVs are operating have been selected and a part of CCTV images are treated to produce sets of training data. The data sets are composed of position and time information of moving objects on CCTV screen which are extracted by initially detecting and tracking of incoming objects into CCTV screen by using a conventional image processing technique available in this study. And the data sets are matched with 6 categories of events such as lane change, stoping, etc which are also involved in the training data sets. The training data are learnt by a resilience neural network where two hidden layers are applied and 9 architectural models are set up for parametric studies, from which the architectural model, 300(first hidden layer)-150(second hidden layer) is found to be optimum in highest accuracy with respect to training data as well as testing data not used for training. From this study, it was shown that the highly variable and complex traffic and incident features could be well identified without any definition of feature regulation by using a concept of machine learning. In addition, detection capability and accuracy of the machine learning based system will be automatically enhanced as much as big data of CCTV images in tunnel becomes rich.

• The Korean Journal of Air & Space Law and Policy
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• v.20 no.2
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• pp.9-58
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• 2005

The Warsaw Convention-officially denominated the "Convention for the Unification of Certain Rules Relating to International Transportation by Air"- is a major multilateral agreement governing the rights and responsibilities of passengers, consignor/consignee and air carriers in international transportation. Article 29(1) of the Warsaw Convention provides that the right to damages shall be extinguished if an action is not brought within 2 years, reckoned from the date of arrival at the destination, from the date on which the aircraft ought to have arrived, or from the date on which the transportation stopped. There has been disagreement as to the nature of this provision. It has been viewed on one hand as a statute of limitations, which may be tolled in appropriate circumstances. Some US Courts which have taken this approach read Article 29(2)-which states that the method of calculating the period of limitation shall be determined by the law of the court to which the case is submitted-as leaving to local law the determination of when the 2-year limitation period provided for in Article 29(1) runs. Therefore, they conclude, under Article 29(2), whenever state law would toll a state statute of limitations, the statute of limitations contained in Article 29(1) would be tolled as well. On the other hand, some other US courts have viewed the 2-year provision contained in Article 29(1) as a condition precedent to the right to bring suit, which will absolutely bar any action not brought within 2 years of the events giving rise to the action. These courts view Article 29(2) as providing only that the forum court should look to the law of the forum on the question whether the plaintiff has taken the necessary measures within the 2-year period to invoke that particular court's jurisdiction over the action. These courts have placed great weight on the "legislative" history of the Convention in reaching this position, noting in particular that the delegates to the Convention expressly considered and rejected a provision, which would have incorporated local tolling provisions.

• Korean Journal of Environment and Ecology
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• v.16 no.3
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• pp.321-337
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• 2002

This study was carried out to draw up the planting plan of bridge type ecological corridor for animals migration at Hakgogae(ridge) destroyed by road construction in Yongin, Gyeonggi-do, South Korea. It was conducted with two steps, survey and planting master plan. We surveyed the structure of topography, plant community, and animal habitat. We also selected the target species migrate ecological corridor and suggested a concept of each planting area, the planting species, and the planting density based on the analyzed data and finally drew up the planting plan. The structure of topography was a steep slope due to the mountain ridge destruction so the bridge type ecological corridor was could be applied in this study and we supposed that the animals migrate along the both edge of corridor. As the results of analyzed plant community structure in two sides, the dominant woody species, Quercus serrata and Q. variabilis were distributed on the bottom and the belly of a mountain, while Pinus densiflora community was distributed on the mountain ridge as edaphic climax. The similarity between Q. serrata -Q. mongolica -Q. variabilis community on the West of survey site and Q. serrata -Q. mongolica community on the East of survey site was high in 71.0 percentages. As the results of surveying birds and some mammalia, seven species and fifty-seven individuals of birds were founded in survey area, and two species and two individuals of rodents were founded. We selected birds and some mammals for the migration species that supposed to migrate ecological corridor in drawing up the planting plan. And then we divided the planting areas into bird corridor and habitat, and mammals corridor, also suggested the planting areas in detail as follows: community planting area of shrub at slope adjacent to the bridge exit as a buffer zone, screen planting area, community planting area of herb at steep slope connected with mountain areas, inducement planting area of the animals, community planting area for bird migration, community planting area for mammals migration, and community planting area for bird habitat. We selected the planting woody species which were the constancy ratio based on the analyzed data of plant community around mountain areas was high, and suggested the planting master plan each space.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.40 no.1
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• pp.26-42
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• 2022

The purpose of this study is to examine and understand the area and the original outer boundaries of Hamchunwon(含春苑), which was the outer royal garden of Gyeonghuigung Palace, which existed before the site of the Russian legation. The results of the study are as follows. First, examining the 3 types of drawings prepared for securing the Russian legation's site and constructing a new building, it was confirmed that two low peaks, which appear to be the original terrain of Hamchunwon, existed in the north and south directions inside the site. According to the initial plan of the of the legation's site, it appears that the entrance of the legation building is connected to the Saemunan-ro in the northwest. However, according to the report made at the time when the Russian temporary minister Veber purchased the legation's site, it was recorded that the site already had a narrow entrance and a dirt road in place, and hence, it was connected to Saemunan-ro. This fact makes it possible to learn that the line of movement for officials and the original gate were located to the northwest of the site planned as the entrance of the legation building towards Hamchunwon. Second, the site was created by cutting the top of the high hill at the time of the construction of the legation building, and as a result, a two tiered staircase typed terrace was built. The ground on which the main building and the secretary's building, etc., were erected was made by cutting the highest peak and solidifying it flat, and a large quantity of soil was used for grading. In the case of the northern area of the main building, the traces of leveling the terrain by cutting the mountains are apparent, and an observation typed garden with a walking path and pavilion was formed by utilizing the physical environment equipped with an easy view. This may be considered as a use which is consistent with the topographical conditions of creating an outer royal garden to block the civilian views on a high terrain overlooking the palace. Third, Hamchunwon's fences were partially exposed in the photos from the 1880s through the 1890s, which demonstrate the spatial changes made around the US, UK, and the Russian legations. As a result of the photo analysis performed, Hamchunwon occupies the northern area of the Russian legation's site, and it is estimated that the north, west, and east walls of the legation resembled those of Hamchunwon. The area to the south of the Russian legation was originally a place made available for civilian houses, and it was possible to examine the circumstances of purchasing dozens of civilian houses and farmlands according to various materials. Fourth, Hamchunwon, which was formed as the outer royal garden of Gyeongdeokgung Palace of Lord Gwanghaegun, lost its sense of place as an outer royal garden when the entire building of Gyeonghuigung Palace was torn down and used as a construction members during the reconstruction of Gyeongbokgung Palace, and faded away as the site was sold to Russia around 1885. The area where Hamchunwon used to be located transformed into a core space of the Russian legation where the main building and garden were located after the construction of the new building. Hence, Hamchunwon, which was limited to the northern area of the Russian legation, does not carry the temporal and spatial context with Gyeongungung Palace and Seonwonjeon which were constructed after 1897, and it is determined that the view of Seonwonjeon as Baehoorim or Baegyeongrim is not valid.