• Title/Summary/Keyword: Artificial stones

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An Experimental Study on Development of Artificial Reefs Using Volcanic Stones for Marine Forests (용암석을 사용한 해중림 조성용 인공 조초 개발에 관한 실험적 연구)

  • Hong, Chong-Hyun;Ghoa, Jong-Hun
    • Journal of Ocean Engineering and Technology
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    • v.22 no.3
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    • pp.103-108
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    • 2008
  • Topics discussed in this paper are engineering design of artificial reefs, design considerations of compressive strength and pH, materials of silica fume concrete and volcanic stones for reef construction, and field monitoring of artificial reefs. Six artificial reefs were deployed offshore at Biyangdo in July 2006, and succession patterns on the reefs were investigated bimonthly from July 2006 to October 2007. The spore-bag method, which has been widely used in Korea for the attachment of seaweed on artificial reefs, was applied to the developed reefs using the kelp Ecklonia cava, which is the dominant species in Jeju, and recruitment and growth patterns were observed.

A Study for the Physical Properties of Artificial Admixtured with β-NSF Base & Vinsol Base Surfactants (β-NSF계와 빈졸계 계면활성제로 변성된 인조석의 물성)

  • Cho, Heon-young;Park, Seong-ki;Suh, Jung-mok;Kim, Jin-man
    • Applied Chemistry for Engineering
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    • v.10 no.4
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    • pp.592-598
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    • 1999
  • Exterior finishing materials of artificial stones are manufactured with the mixture of water, cement, stone powder and light-weight aggregate. In this research, we tried to find a way of increasing the physical properties and decreasing the manufacturing cost of artificial stone. So, we used ${\beta}$-NSF base surfactant and vinsol base surfactant to the artificial stone mixture instead of light-weight aggregate. The optimum dosage of the ${\beta}$-NSF and vinsol surfactants for artificial stone are found to be 1.0 wt % of cement, respectively. The physical properties increased ca. 20% and the durability for freezing & thawing of the new artificial stone increased ca. 300%. While the manufacturing cost of the new artificial stone decreased as much as 30%.

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(A study failure-strength characteristics of soil layer contained Corestone) (핵석을 포함하는 토층의 파괴강도 특성연구)

  • 이수곤;금동헌
    • Proceedings of the Korean Geotechical Society Conference
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    • 2002.03a
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    • pp.711-716
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    • 2002
  • When judging the ground by core-logging, depth of coring might be stopped by coming into view of the moderately weathered rock and also considered as bedrock line. However, highly weathered rock may appear again, if coring more, because there are core-stones in the residual soil and highly weathered rock by the effect of hydraulic-thermal differentiation and does the irregular rock weathering or metamorphic rock region. Therefore, there are room for misunderstanding of diagnosing the moderately weathered rock. Even though the irregular ground where the corestones were come out will show clear geotechnical differences between the ground and the gradually weathered bedrock, nowadays, the construction sites do not take into account the characteristic of core-stone region. In conclusion, to study the failure-strength characteristics of soil layers containing core-stones, we made artificial core-stones and varied percentage of corestones, and measured cohesion and friction factors to adjust them to construction sites containing corestones such as slope, tunnel, and underground.

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Conservation Scheme and Deterioration States of the Wanggung-ri Five-storied Stone Pagoda in the Iksan, Korea (익산 왕궁리 5층 석탑의 훼손현황과 보존방안 연구)

  • Yang, Hee-Jae;Lee, Chan-Hee;Kim, Sa-Dug;Choi, Seok-Won
    • 보존과학연구
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    • s.25
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    • pp.171-195
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    • 2004
  • This research presents an evaluation of the weathering and deterioration state of the Wanggung-ri five-storied stone pagoda in the Iksan (National Treasure No. 289) and suggests conservational schemes. A deterioration map of the pagoda was drawn from the aspects of petrological, physical, chemical, biological, structural and artificial weathering.The rock properties consisting of the pagoda were medium-grained biotite granite that had leucocratic phenocryst developed in parts. The body of each story suffered severely from the secondary contamination that turned the colors into light grey, pitch dark, yellowish brown, and reddish brown as well as granular decomposition, exfoliation and peel-off. The roof stones were heavy exfoliated or peeled off in most of the cases. In addition to the fine cracks, there were layered cracks on the corners. The roof stones of the3rd and 4th story in the north and west side had some stones fall-off, while those of the 2ndstory in the north side had steel reinforcement filled for a fixing purpose. Those of the 5th story showed big gaps that must have originated from cracks and were easily subject to granular decomposition and rainfall. The inside clay filler was missing in the lower part of the roof stones of the 4th and 5th story and the supporting stones, which were thus covered by light grey or pitch dark sediments. The contact area of the materials was about 70 % in the parts where there was a space due to the filler missing and washigher than 90 % in the lower parts of the pagoda. About 90 % or more of the roof stones surface of each story were covered by aerial plants that formed a thick biological mat. Thus it seemed necessary to come up with the conservational measures to remove the plans living on the surface of the stone materials, with the plans to prevent rain from falling inside, and with the water repellent and hardening treatments to postpone the surface weathering of the rock properties. All those measures and plans must be based on the results of long-term monitoring and thorough detail investigations.

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The change of rock properties by artificial weathering tests and its implications for durability of building stones

  • Min Kyoung-Won;Park Jin-Dong
    • 한국지구물리탐사학회:학술대회논문집
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    • 2003.11a
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    • pp.557-560
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    • 2003
  • Some well-known artificial weathering tests such as freezing-thawing, acid immersion, and salt crystallization are adopted to examine the change of rock properties during the processes of artificial weathering. Granites and other rock types of limestone, marble and basalt collected from different quarries in south Korea were sampled for this study. All tests were performed up to 30 cycles and physical properties were measured after experiencing every ten cycles of artificial weathering tests. During the tests, the variation trends of rock properties were too variable to draw generalized variation patterns but it can be concluded that weathering agents have different effect on rock properties depending on weathering circumstance and time. Even in short terms of salt crystallization tests, some rocks were severely deformed and then burst, and in the early stages of salt weathering, recrystallized salts filling pores and cracks in rocks could be a important factor affecting rock properties.

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Original Landscape of MuGi-YeonDang and Yuhoejeong Pavilion Area in Chirwon through (<하환정도(何換亭圖)>를 통해 본 칠원 무기연당(舞沂蓮塘)과 유회정(有懷亭) 일곽의 원형경관)

  • Rho, Jae-Hyun;Son, Hee-Kyung;Park, Tae-Hee
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.35 no.4
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    • pp.1-13
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    • 2017
  • This thesis aims to research the original landscape of an area in Chirwon by comparing and interpreting the current and the former landscape of the time around 1860, in which was created. Inside the painting, MuGi-YeonDang(舞沂蓮塘), its nearby garden facilities and landscape are described. The conclusions of the research are as follows. Around the inner garden(內園) called Gukdam(菊潭), core spaces of Mugi-YeonDang were Hahwanjeong(何換亭) and Pungyongnu(風浴樓). After 1971, Chunghyosa(忠孝祠), Yeongjeonggak(影幀閣) which was built as inheritance of Giyangseowon (沂陽書院), and other buildings were added. On the opposite of Hahwanjeong, there is a designed pond inside Gukdam, in which three pieces of bizarre stones and colorful flower plants and trees reside. In the middle of the pond, there is an center island(中島), constructed with Bonghwangseok(鳳凰石) and Napduseok(衲頭石). Two different kinds of trees are settled on top of the stones, and one of them is identified as a maple. In the external scenery(外境), Jakdaesan Mountain and Cheonjusan Mountain are located at the upper part of Mugi-Yeondang, and Bibo Forest(裨補林), which does not exist anymore, was located at the lower part of it. A notable achievement in own research was to discover the Ju family's graveyard(朱氏墓群) consisted of more than 10 murals at the lower part of Mt. Jakdaesan in the outer space and the remains of 'Byeoreop(別業) Yuhoejeong(有懷亭)' at the nearby Sanjeong-ri(山亭里) area, which was the Ju family's gravesite(Seonsan, 先山). The discovered remains showed the presence of a square pond(方塘) and an island in the center of it(中島) in the form of Seokgasan(an artificial mountain made with stones), a stone monument called Mangchudae(望楸臺), etc. The Seokgasan was consisted of processed natural stones, and layers of the stones were piled up for it. On the side of the layered stones, 'Gyeongam(敬嵒)' and 'Sesim(洗心)' are engraved. Especially, Gyeongja(letter Gyeong, 敬字) is a copy of the Gyeongja Rock(敬字岩) of Sosu-Seowon(紹修書院), which is a symbolic garden language mutually used in the signboards of Pungyongnu and Musansa(武山祠), a place built to enshrine Ju, Sebung(周世鵬). Through the written names of the building found in , it can be assumed that the name of the square pond with Seokgasan was Taehwaji or Jeongwudang, and the name of the Seokgasan was Sogeumgang(小金剛) or Sobangjang(小方丈). The names correspond to the names of the Seokgasan of Gukdam, which was Yangsimdae(養心臺) and Bongnaesan(蓬萊山). By means of the corresponding names, it can be inferred that the relations between the spaces were intended. was originally created as 'a manor painting(莊園圖)', led by the 15th generation of the Ju family who moved into Chirwon-ri, Haman. The painting describes not only the back garden but also the external scenery, thus it provides important evidences for understanding Mugi-YeonDang and its nearby landscape, and is helpful to its maintenance and restoration.

Improvement Plan for Artificial Ground Landscaping of Underground Parking Lot in Apartment Complex (공동주택단지 인공지반 식재환경 개선방안)

  • Kang, Myung Soo;Moon, Seog Gi;Kim, Nam Jung
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.17 no.5
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    • pp.51-64
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    • 2014
  • Most planting grounds have converted to the artificial ground of the upper part of underground parking lot in apartment complex recently by increasing utilization of underground parking area. This study has examined the composition of each ground and planting status. The study presents problems of planting plans in artificial ground landscaping in apartment complex. This study has conducted reference and field research. It has researched green space planning, planting characteristics and measures condition of soil depth in 3 regions surveyed. The results are listed below. First, hybrid ground has the highest percentage and natural soils has the lowest percentage in the composition of green space in apartment complex. Artificial green space is composed of a number of small-scale grounds. Second, The study has found that planting characteristics don't reflect soil properties. On the other hand, planting deep rooting big arbors has a high proportion in artificial Ground. Third, the study has figured out 98% of fit in minimum soil depth for growth. Fourth, planters and landscaping stones are constructed in case of small green space. On the other hand, mounding is constructed in case of large green space. However in case of mounding types it has low fit, so it needs to improve this problem.

Research on the Development of Artificial Organs based on the Physical Properties of the Human Body (인체의 물리적 성질을 이용한 인공장기 개발 연구)

  • Lee, SeungBock
    • The Journal of the Korea Contents Association
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    • v.22 no.7
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    • pp.670-675
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    • 2022
  • In the era of the 4th industrial revolution, everything is data-centric. The type and amount of data may be central, and new data may be required in special circumstances. As 3D printers are used in various fields, there are fields that are newly challenged. In particular, in the medical field, new attempts that have not been considered before are taking place. This paper is a study to enable research in fields that require physical properties of the human body. In the meantime, research using human organs has mainly used the materials made of silicon. We measure the physical properties of the human body from cadavers, apply these characteristics to develop new materials, and develop artificial organs with 3D printers. Using the artificial organs made in this way, you can practice surgery with a robot that removes kidney stones. In this paper, we would like to introduce a series of research processes to develop advanced materials similar to human organs.

A Program for University Student's IT Leadership Renovation

  • Park, Jong-Jin
    • International Journal of Internet, Broadcasting and Communication
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    • v.12 no.1
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    • pp.1-6
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    • 2020
  • In this paper, we propose a new program for university student's IT leadership renovation. Automation and Artificial Intelligence(AI) are changing the nature of work. According to MGI report, they will change the skills needed in the workforce. Leadership is one of the skills needed more of in the future at workplace including IT industry. Leadership could be defined as having 5 level leadership. According to the 5 level leadership, a program was formulated to renovate university student's self-leadership, teamwork, team leadership and finally global leadership. We named the program as Stepping-Stone Platform for Student's IT Leadership Renovation(SSP-SLR). Each level of four stepping stones consists of one semester. Student can raise their leadership skills by the program step by step. Various instruction learning methodologies are adopted to the program, including Flipped learning which has been proved effective in many ways in the field of education recently.

A Study on the Architectural Characteristics of the Jeju Province Recreational Pension (제주도 휴양펜션시설의 건축실태에 관한 연구)

  • Kim Bong-Ae;Jeong Byeol-Ah
    • Journal of the Korean housing association
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    • v.16 no.5
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    • pp.21-27
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    • 2005
  • The purpose of this study is to prepare desirable recreational pension facilities system in compliance with various characteristics of each region and to help establish policies regarding recreational pension facilities. This research is carried out by an on site inspection and the survey of the management of the recreation facilities. Jeju recreational pensions have the following characteristics : The site area is $1305{\sim}7850\;m^2$, the number of guest rooms are $8{\sim}10$, and the area of the guest rooms are $33{\sim}99\;m^2$. In addition, most of them are built with R.C. structure and the exteriors are made of artificial stones. As for plot plan, it has 5 types of prototype : type of outbuilding, arranging in a row, corridor, hall, and the composition of the other types. Although Jeju recreational pension were institutionalized to satisfy the functions as tourism recreations, they don't reflect the unique characteristics of Jeju province.