• Journal of architectural history
• /
• v.19 no.6
• /
• pp.39-59
• /
• 2010

Seokgatap and Dabotap are representing the tower patterns in "Gyeonbotappum" of the Lotus Sutra. It is very peculiar, for the description on "Gyeonbotappum" is usually made in terms of 'the two Buddhas sitting side by side'. If 'the two Buddhas sitting side by side' is describing the situation in Dabotap, the double structure of Seokgatap and Dabotap can be said to symbolize the scriptural description in a different viewpoint. Its correct comprehension is pretty important in understanding Bulguksa. For this, this paper first arranged the critical minds and flows about the faith objects in Indian Buddhism. And, it was considered how these aspects were accumulated through Saddharma-pundarika sutra. Secondly, it was considered why "Gyeonbotappum" took the typical symbolism in Saddharma-pundarika sutra(Lotus Sutra). These parts should be necessarily considered in advance in that Seokgatap and Dabotap were derived from the form of "Gyeonbotappum". Based on this approach, the author checked the actual aspects of Seokgatap that the tower was built on a natural rock ground and the stones surrounding the tower are constituting the 8-directional Lotus site. With these two aspects, we could get the clue on the foundation time of Bulguksa that its founder had intended. In that Dabotap was formed on the basis of "Gyeonbotappum", the features of Dabotap is very important in comprehending its foundation viewpoint. As a result, the viewpoint of double towers in Bulguksa can be said to be the one that the world of suffering was to change to the Pure Land after Sakyamuni preached the Lotus Sutra on the top of Mt. Grdhrakuta and Prabhutaratna-tathagata proved it. This foundation viewpoint shows us clearly that 'the Lotus Buddhist Country' existed in parallel to the Avatamska Buddhist Country. It secures an appropriate meaning in that it can complement or adjust our understanding on the 'Buddhist country (Bulguk)' of Bulguksa where the Avatamska Idea is emphasized relatively highly as shown in the whole title of Bulguksa as 'Avatamska Bulguksa.'

• Journal of Radiation Protection and Research
• /
• v.29 no.3
• /
• pp.197-204
• /
• 2004

Vertical distributions of $^{137}Cs\;and\;^{90}Sr$ activities are studied for the soils of six areas, Korea (Gori, Yeonggwang, Uljin, Weolseong, Goseong and Jeju). The soils from 6 areas are at geographically different locations with the different environmental conditions and parent rook. The activities of $^{137}Cs\;and\;^{90}Sr$ vary N.D.(below detection limit) to 185 Bq/kg and 2.79 - 8.06 Bq/kg, respectively. Activities of $^{137}Cs\;and\;^{90}Sr$ show the highest value at the surface soil and decrease with depth. $^{137}Cs$ activities at the top surface soils are positively correlated with annual precipitation and organic carbon content with little relationship with mean grain size and the clay content. The highest $^{137}Cs$activities are found at the Jeju site, followed by the Goseong site of which soils have much different parent rock and textural properties. Though the activities of $^{137}Cs\;and\;^{90}Sr$ on the basis of dry weight are higher in Jeju soils than in Goseong soils, their inventories are similar in both soils due to their textural differences.

• Journal of the Korean GEO-environmental Society
• /
• v.7 no.2
• /
• pp.67-76
• /
• 2006

For a hydro power plant project, the headrace tunnel having a finished diameter of 3.3 m was constructed in volcanic rocks with well-developed vertical joint and high groundwater table. The intake facility was located 20.3km upstream of the powerhouse and headrace tunnel of 20km in length and penstock of 440m in height connected the intake and the powerhouse. The typical caldera lake, Lake Toba set the geology at the site the caving of the ground caused tension cracks in the vertical direction to be developed and initial stresses at the ground to be released. High groundwater table(the maximum head of 20bar) in the area of well-connected vertical joints delayed the progress of tunnel excavation severely due to the excessive inflow of groundwater. The excavation of tunnel was made using open-shield type TBM and mucking cars on the rail. High volume of water inflowraised the water level inside tunnel to 70cm, 17% of tunnel diameter (3.9m) and hindered the mucking of spoil under water. To improve the productivity, several adjustments such as modification of TBM and mucking cars and increase in the number of submersible pumps were made forthe excavation of severe water inflow zone. Since the ground condition encountered during excavation turned out to be much worse, it was decided to adopt PC segment lining instead of RC lining. Besides, depending on the conditions of the water inflow, rock mass condition and internal water pressure, one of the invert PC segment lining with in-situ RC lining, RC lining and steel lining was applied to meet the site specific condition. With the adoption of PC segment lining, modification of TBM and other improvement, the excavation of the tunnel under severe groundwater condition was successfully completed.

• Journal of Conservation Science
• /
• v.37 no.5
• /
• pp.411-425
• /
• 2021

The Stupa of State Preceptor Jigwang from Beopcheonsa Temple Site in Wonju (National Treasure) is a representative stupa of the Goryeo Dynasty, with outstanding Buddhist carvings and splendid patterns, clearly indicating its honoree and year of construction. However, it was destroyed by bombing during the Korean War (1950-1953) and repaired and restored with cement and reinforcing bars in 1957. The surface condition of the original stone shows long-term deterioration due to the m ortar used in past restorations. In order to identify the exact causes of deterioration, the m ortar and surface contaminants on the original stone were analyzed. Portlandite, calcite, ettringite, and gypsum from the mortar were identified, and its ongoing deterioration was observed through pH measurements and the neutralization reaction test. Analysis of surface contaminants identified calcite and gypsum, both poorly water-soluble substances, and their growth in volume among rock-forming minerals was observed by microscopy. Based on those results, semi-quantitative analysis of Ca and S contents significantly influencing the formation of salt crystals was conducted using P-XRF to analyze the basis of surface deterioration, and cross-validation was performed by comparing the body stone affected by the mortar and the upper stylobate stone unaffected by the mortar. Results indicate that the elements are directly involved in the surface deterioration of the body stone.

• Korean Journal of Heritage: History & Science
• /
• v.49 no.3
• /
• pp.104-135
• /
• 2016

This paper aims to consider history and value of the Mingshansi Grottoes, a complex of Buddhist rock sculptures in Anyue County, Sichuan Province, China. Mingshansi Shiku, not that far from Baodingshan Grottoes at Dazu District, Chongqing City, is an important art work of Liu Benzun sect. Even though there are not many niches and sculptures in the Mingshansi Shiku, it was designated as a Major Historical and Cultural Site Protected at the National Level due to its large scale and highly valued art works in it. In the Mingshansi Grottoes there is not any information inscribed on the rockface about when the grottoes were established. Because a stone pagoda, which had information about when and by whom they were established, was collapsed, some scholars considered them to be made in North Song or early Southern Song Dynasties based only on the artistic style of sculptures of the grottoes. The School of Archaeology and Museology at Peking University recently carried out a survey documenting the Mingshansi Grottoes, and thereby the school gives an important material for studying the grottoes. The grottoes consist of a Dharma-protection Warrior niche, a statue of Guanyin and Dashizhi seated together, a standing Mahavairocana statue, a standing Manjushuri statue, a standing Wenshu and Puxian statue, a Turning Dharma-wheel pagoda (轉法輪塔 Zhuanfalunta) of Zhao Zhifeng, the founder of Liu Benzun sect. These statues are considered to be produced by an overall master plan in the Middle or Late Period of the Southern Song. The Shiku is believed to be a site at which Zhao Zhifeng performed some Buddhist rites such as Water and Land Rituals (水陸法會 Shuilufahui). Income of the ritual was also a major part of the funding for establishing large-scale Baoding Shiku at Dazu District, Chongqing City.

• Journal of the Korean Geotechnical Society
• /
• v.37 no.1
• /
• pp.29-41
• /
• 2021

Although underground works are essential to use underground spaces in urban areas efficiently, various damages caused by constructions have often occurred, making them major social problems. Since 2018, it is stipulated in the Special Act on Underground Safety Management that appropriate construction methods must be used in the design stage to prevent various damage cases. This Special Act includes establishing an area subject to underground safety impact assessment, analysis of ground and geological status, review of effects caused by changes in groundwater, review of ground safety, and establishment of measures to secure underground safety. This study area consists of various strata in order of landfill, sedimentary silt, sedimentary sand, sedimentary gravel, weathering zone, and foundation rock. Also, the slurry wall, a highly rigid underground continuous wall, was chosen as a construction method to consider high water table distribution and minimize the influence of the surroundings in this area. However, ground subsidence occurred on the road nearby in December 2019 due to the inflow of loosening soil to the construction area. Thus, several types of site investigations were conducted to suggest an appropriate analysis method and to find out loosed ground behavior and its area for the subsided site. As a result, new design soil properties were re-calculated, and the reinforcement measures were proposed through analytical verification.

• The Journal of Engineering Geology
• /
• v.10 no.3
• /
• pp.205-216
• /
• 2000

An unstable natural slope located at Icheon-Ri, Dasa-Eup, Dalseong-Kun which has been severely cracked during heavy rain fall in September, 1998, was investigated and analysed for remedial measures. Various geological data were obtained by performing a surface geological survey, a ground penetrating radar(GPR) exploration, four geotechnical borings with field and laboratory tests, and the precipitation records were also reviewed. Based on the these data, the probable sliding plane was determined as a bedding plane with dip angle of 20 to 25 degrees between sandstone and shale layers at depth of 6 to 8 meters. By performing back analyses with the limit equilibrium method, the friction angle and cohesion of the sliding plane were determined as 18$^{\circ}$ and 0, respectively. Based on these results, a series of stability analyses such as stereo-graphic projection method, limiting equilibrium method and numerical method were carried out. The remedial measures for the unstable slope were selected based on the results of the limit equilibrium analyses by considering various conditions expected at the site. Ground grouting or anchoring method with proper surface drainage systems could be employed for the long term safety of the slope.

• Explosives and Blasting
• /
• v.30 no.2
• /
• pp.52-58
• /
• 2012

A TBM launching shaft in DTL2 Contract 915 site is located in a typical hard Bukit Timah granite formation and lots of blasting work is required for shaft sinking. The original blast design used the electric detonator and ANFO blasts consisting of 30 holes per one blast with 1.5 m depth of drilling hole. However, significant delay of work and poor progress were expected due to the limitation of the number of blasting hole and strict vibration regulation on retaining systems. To overcome such constraints, an efficient new blasting method which can improve productivity and satisfy vibration limit was required. The revised blast design, using triple-deck blasts with electronic detonators and cartridge emulsion explosives, gives better construction performance and can reduce construction time. Such a new blasting technique can be effectively used for similar underground projects in the future where the volume of rock blasting is significant.

• The Journal of Korean Academy of Prosthodontics
• /
• v.51 no.4
• /
• pp.323-331
• /
• 2013

Soft tissue collapse around prepared teeth and pontic is inevitable after removal of the provisional restoration during the impression taking procedures. When inserting gingival retraction cord, soft tissue is displaced to an undesired contour. Viscosity of impression material also causes gingival displacement. Therefore, the consideration to transfer the prosthetically contoured soft tissue to master cast is required, especially in the esthetic area. In this report, the methods to maintain the soft tissue contour and transfer to the mastercast will be introduced. Harmonious contour of the soft tissue can be achieved with provisional restoration and be transferred to the master cast with two different techniques mentioned in this case report.

• Korean Journal of Soil Science and Fertilizer
• /
• v.47 no.2
• /
• pp.113-119
• /
• 2014

Arsenic and its compounds which is one of the most toxic elements that can be found naturally on earth in small concentrations are used in the production of pesticides, herbicides, and insecticides. Most arsenic that cannot be mobilized easily when it is immobile is also found in conjunction with sulfur in minerals such as arsenopyrite (AsFeS), realgar, orpiment and enargite. In this investigation we observed the leaching of arsenic in soils amended with several levels of gravel size of arsenopyrite collected from a road construction site. Soil and gravel size of arsenopyrite were characterized by chemical and mineralogical analyses. Results of XRF analysis of arsenopyrite indicated that the proportion of arsenate was 0.075% (wt $wt^{-1}$) while the maximum amount of arsenic in soil samples was 251.3 mg $kg^{-1}$. Cumulative amounts of effluent collected from the bottom of the soil column for different mixing rate of the gravel were gradually increased where proportion of the gravel mixed was greater than 70% whereas the effluent was stabilized to the maximum after approximately 45 pore volumes of effluent or greater were collected. The arsenic in the effluent was recovered from the soil columns in which the proportion of arsenopyrite gravel was 60% or greater. The total amount of arsenic recovered as effluent was increased with increasing proportion of gravel in a soil, indicating that the arsenic in the effluent was closely related with gravel fraction of arsenopyrite.