• KEPCO Journal on Electric Power and Energy
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• v.6 no.3
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• pp.305-313
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• 2020

The use of cable tunnels for electric power transmission as well as their construction in difficult conditions such as in subsea terrains and large overburden areas has increased. So, in order to efficiently operate the small diameter shield TBM (Tunnel Boring Machine), the estimation of advance rate and development of a design model is necessary. However, due to limited scope of survey and face mapping, it is very difficult to match the rock mass characteristics and TBM operational data in order to achieve their mutual relationships and to develop an advance rate model. Also, the working mechanism of previously utilized linear cutting machine is slightly different than the real excavation mechanism owing to the penetration of a number of disc cutters taking place at the same time in the rock mass in conjunction with rotation of the cutterhead. So, in order to suggest the advance rate and machine design models for small diameter TBMs, an EPB (Earth Pressure Balance) shield TBM having 3.54 m diameter cutterhead was manufactured and 19 cases of full-scale tunneling tests were performed each in 87.5 ㎥ volume of artificial rock mass. The relationships between advance rate and machine data were effectively analyzed by performing the tests in homogeneous rock mass with 70 MPa uniaxial compressive strength according to the TBM operational parameters such as thrust force and RPM of cutterhead. The utilization of the recorded penetration depth and torque values in the development of models is more accurate and realistic since they were derived through real excavation mechanism. The relationships between normal force on single disc cutter and penetration depth as well as between normal force and rolling force were suggested in this study. The prediction of advance rate and design of TBM can be performed in rock mass having 70 MPa strength using these relationships. An effort was made to improve the application of the developed model by applying the FPI (Field Penetration Index) concept which can overcome the limitation of 100% RQD (Rock Quality Designation) in artificial rock mass.

• Journal of Wetlands Research
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• v.17 no.2
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• pp.184-192
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• 2015

This study is a basic research for low maintenance constructed wetlands which can prevent water quality deterioration due to wetland soils. The purpose of this study is to analyze water quality control mechanisms of constructed wetland on the artificial ground which installed the modular revetment structure(MRS), a device that separates water and soil. This study was then conducted with two different wetland mesocosms (a treatment plot and a control). These mesocosms were monitored to analyze effects of water quality control of the MRS. A treatment plot was built, and separated into soil and water, by filling the MRS with the decomposed granite soil in the mesocosm made of rubber material. A control plot was built where the decomposed granite soils were exposed to water by leaving the soil on the bottom of the mesocosm made of rubber material. Water quality was then analyzed by using Kolmogorov-Smirnov Z examination which then showed that pH, BOD, SS, Chl-a, T-P, T-N had statistically valid difference between a container with the MRS and one without it. According to the analysis of the water quality, the temperature and the EC level came out similarly and both mesocosm showed same level on pH and DO. A treatment plot had higher levels of BOD, SS Chl-a, and T-P. A control plot's T-N value was little lower than that of the treatment plot. This study suggests method of constructed wetlands using the MRS prevents problems occurring in wetland soils: aridity of wetlands by soil erosion, eutrophication, and algal blooms due to nutrients released from wetland soil. These functions of constructed wetland with the MRS increase aesthetic, ecologic, social, and economic value of the wetland. Outcomes of this research will later enable more proficient way of stabilizing water quality and provide data for planning low maintenance constructed wetlands.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.31 no.4
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• pp.113-122
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• 2013

In this study, the traditional structure of the impact on the stability analysis. Korean traditional landscape architecture column space of stonework stable composition as the foundation of the fence for a long time been known to fall down and not maintained. The destination of research Ohgokmun Damyang Soswaewon fence which is in harmony with nature is one of the traditional structures that affect its shape without being kept so far came true. This includes our ancestral wisdom and that wisdom can guess guesswork. But I let the traditional reproduction incidence structures frequently. This deviation from the traditional method of construction application of shorthand stand. Thus, the subject of this study, the factors that do not fall down fences Ohgokmun solution is to indirectly gain the weak. In addition, epidemiological studies and the methods of calculation of the inferred physical examination, the results of the analysis were derived through the following. First, the internal factors of the fence Ohgokmun constituting the structural member and the coupling of the scheme. 1) based on stable ground. Greater role in the country rock The fact that the settlement will have no symptoms. 2) to minimize the friction caused by hydrological water to remove the two-pronged process through stone work building form and menu sustaining power in hydrology and flooding made against the bypass channel. 3) due to the load bearing capacity and durability to withstand the strength of the material and the construction of structures in the form of a dispersion of power between each individual to maximize the process of getting traction was applied. Second, external factors Ohgokmun fence the results obtained through the calculation of the dynamics of repair, is greatly affected by the wind and the water gate of the fence, but the action of the structural stability of the lack of power that hurt enough conclusion. In this study, the results of the structure of internal and external influence as well through the structure can be viewed as composed consisting. However, over the next follow-up in terms of climate and environmental factors due to the fact that the fall might.

• Journal of Korean Tunnelling and Underground Space Association
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• v.21 no.1
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• pp.61-77
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• 2019

If a new utility tunnel is planned for high density existing urban areas in Korea, a rational decision-making process such as the determination of optimum design capacity by using the feasibility evaluation system based on quantitative evaluation indexes and the economic evaluation is needed. Thus, the previous study presented the important weight of individual higher-level indexes (3 items) and sub-indexes (16 items) through a hierarchy analysis (AHP) for quantitative evaluation index items, considering the characteristics of each urban type. In addition, an economic evaluation method was proposed considering 10 benefit items and 8 cost items by adding 3 new items, including the effects of traffic accidents, noise reduction and socio-economic losses, to the existing items for the benefit cost analysis suitable for urban utility tunnels. This study presented a quantitative feasibility evaluation method using the important weight of 16 sub-index items such as the road management sector, public facilities sector and urban environment sector. Afterwards, the results of quantitative feasibility and economic evaluation were compared and analyzed in 123 main road sections of the Seoul. In addition, a comprehensive evaluation method was proposed by the combination of the two evaluation results. The design capacity optimization program, which will be developed by programming the logic of the quantitative feasibility and economic evaluation system presented in this study, will be utilized in the planning and design phases of urban community zones and will ultimately contribute to the vitalization of urban utility tunnels.

• Korean Journal of Heritage: History & Science
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• v.53 no.4
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• pp.78-99
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• 2020

The Buddha triad and 16 Arhat statues carved on the rock surface at Seongbulsa temple is the only domestic remaining example of all 16 Arhats, so its academic value is very high. However, it is severely damaged and so required a stability evaluation through study of digital documentation and precise diagnosis for the purpose of comprehensive conservation. This process established that the Buddha statues were of similar scale, while the Arhats showed a wide variety of sizes, and the two kith and kin in the volume were larger than the Arhats. It was estimated that the statues of food for Buddha are similar to the Arhat statues, and most of the statues are well-formed. The rock used to carve the Buddha statues is banded gneiss with distinct foliation, alternating between white bands of quartz and feldspar and black bands composed of biotite. The Buddha statues have been damaged by physical weathering, discoloration, and biological contamination. In damage evaluations, joint (3.6 crack index), peeling (5.2%), exfoliation (1.7%), and falling off (0.1%) were observed on the rock surface of the Buddha statues. In particular, due to severe biological weathering, stage 9 and 10 biological coverage of the rock surface accounted for 57.5% of the total area, and stages 5 to 8 also accounted for a high share at 22.3%. The discoloration factors were shown to be dark brown and white with Fe, Ca, and S, and a large amount of C detected in the blackened contaminants, and the damage weight high in all areas. Discontinuities in different directions were identified in the rock surface. Analysis of potential rock failure types indicated that there is a possibility of plane and toppling failure, but wedge failure is unlikely to occur. The mean ultrasonic velocity of the main rock surface was 2,463m/sec, the lower part of the left side with a large number of joints was relatively low, and the highly weathered (HW) type to the completely weathered (CW) type concentrated distribution, showing weak properties. For the Buddha statues, conservation treatment is required for about 14.9% of micro cracks and 58.9% of exfoliation cracks. In addition, in order to improve the conservation environment of the Buddha statues, maintenance of drainage and ground preparations for the rock surface gradient and plants are necessary, and protection facilities should be reviewed for long-term conservation and management purposes.

• Journal of the Daesoon Academy of Sciences
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• v.37
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• pp.329-355
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• 2021

The objective of this paper is to reveal that the formation of Deleuze's system is a result of a back flow of the 'ideal of pure reason' in Kant's system. I will try to seize upon the keyword in his main book, Difference and Repetition, and examine the aspect of mutual transformation between Deleuze's transcendental empiricism and Kant's transcendentalism. When analyzing Deleuze's system, most researchers tend to focus on anti-Hegelianism, but it is proper that Kant be adopted as the start when tracing the way of deployment directly. Fundamentally, Deleuze is different from Hegel in his approach to observing entire ground of thought. Even if Deleuze surely has the capability of becoming in the dialectical context, his systemic environment wherein dialectics is applied is different even at the onset. While Hegel follows the way of origin and copy or a system that begins from a preceding point of origin, Deleuze follows a way of copy and recopy or a system that begins without a point of origin. This characteristic of Deleuze's system originates directly from idealistic play. In fact, we can anticipate and identify in his book that he refers to Kant who accepted the tradition of empiricism. Therefore, the main contents of this paper is to present an overview of Kant's influence on Deleuze's system. While tracing ideas back to Kant's system, the cohabitation of empiricism and rationalism, which Kant felicitously revoiced, there emerges a definitude of world recognition. This occurs through cohabitation, and this is both deconstructed and integrated by Deleuze, and therein definitude is turned into a vision of prosperity. To the vision of prosperity that spans definitude to recognition, a philosopher has the right to select a philosophical system because selection methodology in philosophy is not a problem of legitimacy so much as the needs of the times. Deleuze's choice resulted in the opening of pandora's box in an abyss and secret contents have in turn risen sharply.

• The Journal of Engineering Geology
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• v.33 no.2
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• pp.275-291
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• 2023

Global warming has made the polar regions more accessible, leading to increased demand for the construction of new resource-development plants in oil-rich permafrost regions. The selection of locations of resource-development plants in permafrost regions should consider the surface displacement resulting from thawing and freezing of the active layer of permafrost. However, few studies have considered surface displacement in the selection of optimal locations of resource-development plants in permafrost region. In this study, Analytic Hierarchy Process (AHP) analysis using a range of geospatial information variables was performed to select optimal locations for the construction of oil-sands development plants in the permafrost region of southern Athabasca, Alberta, Canada, including consideration of surface displacement. The surface displacement velocity was estimated by applying the Small BAseline Subset Interferometric Synthetic Aperture Radar technique to time-series Advanced Land Observing Satellite Phased Array L-band Synthetic Aperture Radar images acquired from February 2007 to March 2011. ERA5 reanalysis data were used to generate geospatial data for air temperature, surface temperature, and soil temperature averaged for the period 2000~2010. Geospatial data for roads and railways provided by Statistics Canada and land cover maps distributed by the North American Commission for Environmental Cooperation were also used in the AHP analysis. The suitability of sites analyzed using land cover, surface displacement, and road accessibility as the three most important geospatial factors was validated using the locations of oil-sand plants built since 2010. The sensitivity of surface displacement to the determination of location suitability was found to be very high. We confirm that surface displacement should be considered in the selection of optimal locations for the construction of new resource-development plants in permafrost regions.

• Asian Journal of Turfgrass Science
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• v.17 no.4
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• pp.129-146
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• 2003

Research was initiated to compare establishment vigor, uniformity, rooting potential and turf quality in sods of cool-season grasses (CSG). Several turfgrasses grown under pure sand soil were tested. Establishment vigor, uniformity, rooting potential and turf quality were evaluated in the study. Turfgrass entries were comprised of three blends from Kentucky bluegrass (KB, Poa pratensis L.), perennial ryegrass (PR, Lolium perenne L.), and tall fescue (TF, Festuca arundinacea Schreb.), respectively and three mixtures among them. Differences by treatments were significantly observed in establishment vigor, uniformity, rooting potential and turf quality. Early establishment vigor was mainly influenced by germination speed, being fastest with PR, intermediate with TF and slowest with KB. In a late stage of growth, however, it was affected more by growth habit, resulting in highest with KB and slowest with TF. There were considerable variations in sod uniformity among turfgrasses. Best uniformity among monostand sods was associated with KB, while poorest one with TF. PR sod produced intermediate uniformity between KB and TF. The uniformity of polystand sods of CSG mixtures was inferior to that of monostands of KB, PR and TF, due to characteristics of mixtures comprised of a variety of color, density, texture and growth habit. The greatest potential of sod rooting was found with PR and the poorest with KB. Intermediate potential between PR and KB was associated with TF. In CSG mixtures, it was variable, depending on turfgrass mixing rates. Generally, the higher the PR in mixtures, the greater the sod rooting potential. At the time of sod harvest, however, turfgrass quality of KB was superior to that of PR. because of its characteristics of uniform surface, high density and good mowing quality. These results suggest that a careful expertise based on turf quality as well as sod characteristics like establishment vigor, uniformity and rooting potential be strongly required for the success of golf course or athletic field in establishment.

• 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.

• Economic and Environmental Geology
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• v.8 no.2
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• pp.73-87
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• 1975

Regional unconformities have been used as boundaries of major stratigraphic units in Korea. The term "synthem" has already been propsed for formal unconformity-bounded stratigraphic units of maximum magnitude (ISSC, 1974). The unconformity-based classification of the strata in the cratonic area in Korea comprises in ascending order the Kyerim, $Sangw{\check{o}}n$, $Jos{\check{o}}n$, $Py{\check{o}}ngan$, Daedong, and $Ky{\check{o}}ngsang$ Synthems, and the Cenozoic Erathem. The unconformites separating them from each other are either orogenic or epeirogenic (and vertical tectonic). The sub-$Sangw{\check{o}}n$ unconformity is a non-conformity above the basement complex in Korea. The unconformities between the $Sangw{\check{o}}n$, $Jos{\check{o}}n$, and $Py{\check{o}}ngan$ Synthems are disconformities denoting late Precambrian and Paleozoic crustal quiescence in Korea. The unconformities between the $Py{\check{o}}ngan$, Daedong, and $Ky{\check{o}}ngsang$ Synthems are angular unconformities representing Mesozoic orogenies. The bounding unconformities of the $Ky{\check{o}}ngsang$ Synthem involve non-conformable parts overlying the Jurassic and late Cretaceous granitic rocks.