• Title/Summary/Keyword: ring foundation

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Tree-Ring Growth Characteristics of Zelkova serrata Makino after Replanting on the Reclaimed Land from the sea in Gwangyang Bay (광양만 임해 매립지 느티나무 이식 이후의 연륜생장 특성)

  • Kim Do-Gyun
    • Journal of the Korean Institute of Landscape Architecture
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    • v.33 no.6 s.113
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    • pp.40-50
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    • 2006
  • This study was carried out to examine the tree-ring growth characteristics of Zelkova serrata Makino after replanting, for the built-up planting founds for stability of landscaped trees in the reclaimed land from the sea. the factors, many affecting the growths of Zelkova serrata Makino, were the replanting stress and drought. The growth reduction due to replanting and drought occurred in the replanting year and the following year. The mean sensitivity(year-to-year variation) and the coefficient of variation(tree-to-tree variation in a certain year) in tree rings of Zelkova serrate Makino, were higher in the poor soil sites than in the favourable soil ones. And the poor soil sites were the filled ground of improve soil and the covered ground of improve soil and the top ground of big mounding than mounding ground sites, especially soil hardness, alkali soil, high $Na^+\;and\;K^+,\;low\;Ca^{++}\;and\;Mg^{++}$ and T-C were the most crucial. We suggest technique development of the built-up planting ground for stability in the reclaimed land from the sea. The built-up planting grounds in reclaimed land from the sea, should be considered for the use of fair soil with the physical and chemical soil properties, -high level foundation of planting ground, and the prevention of disturbed soil-.

A Study on the Characteristics of Bearing Capacity for Rammed Aggregate Pier in Sand (사질토지반에서 짧은 쇄석다짐말뚝의 배치형태에 따른 지지력특성에 관한 연구)

  • Chun, Byung-Sik;Kim, Young-Hun;Yoo, Woo-Hyun;Kim, Jong-Hwan
    • Proceedings of the Korean Geotechical Society Conference
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    • 2009.03a
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    • pp.195-198
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    • 2009
  • Rammed Aggregate Pier method is intermediate foundation of deep and shallow foundation, it has been built on world wide. But the investigation and research in domestic is not accomplished. In this paper, examined details of different spacing of piles, bearing capacities, respectively, conclude with recommendations on how RAP can be used in future needs. This documentation further provides comparisons of the laboratory test results which were obtained from differenciate the spacing of piles, namely installed rammed aggregate pier. Strain control test was conducted to determine the bearing capacities of the piers; 20mm, 30mm and 40mm diameter drilling equipment to drill holes were installed in sand at initial relative densities of 40%. By comparing different spacing of piles, in this experiment, piles are spaced structually span, form a ring shape, narrowing the distance of each other, to the center. the result shows that as diameter of pier is bigger in diameter, bearing capacity also dramatically increased due to raised stiffness. Also, the space between each piers narrowed, settlement rate of soil was decreased significantly. From the test results, as the space between each piles were getting closer, allows greater chances to have resistance to deformation, shows improved stability of structures.

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Thermal Conductivity Estimation of Soils Using Coil Shaped Ground Heat Exchanger (코일형 지중열교환기를 이용한 지반의 열전도도 산정)

  • Yoon, Seok;Lee, Seung-Rae;Park, Hyunku;Park, Skhan
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.32 no.5C
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    • pp.177-183
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    • 2012
  • The use of energy pile foundation has been increased for economic utilization of geothermal energy. In particular, a coil-shaped ground heat exchanger (GHE) is preferred than conventional U-shaped heat exchanger to ensure better efficiency of heat exchange rate. This paper presents experimental results by changing different pitch spaces of spiral coils. Joomunjin sand was filled in a steel box of which the size was $5m{\times}1m{\times}1m$. Thermal response tests (TRTs) were conducted to measure the ground thermal conductivity with temperatures of circulating water using line source model and ring coil model. Experimental results and analytical solutions were compared to validate the applicability of these models. Ring coil model showed more accurate similar results with experimental data rather than line source model and cylindrical source model.

Endotracheal tube damage during surgically assisted rapid palatal expansion surgery; a case report

  • Badger, James
    • Journal of Dental Anesthesia and Pain Medicine
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    • v.20 no.1
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    • pp.45-47
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    • 2020
  • Endotracheal tube damage is a well-known complication of maxillary surgery. We report a case of failure to ventilate due to superficial damage to the tubing between the cuff and pilot balloon in the nasal portion of a north facing Ring, Adair and Elwyn pre-formed endotracheal tube during Surgically Assisted Rapid Palatal Expansion surgery. The endotracheal tube was replaced uneventfully and surgery completed successfully. On reflection, we feel that that the vulnerable position of the cuff-pilot tubing significantly contributed to this critical incident and suggest that increased recognition of this is vital for the prevention of such cases in the future.

ANNIHILATOR CONDITIONS ON RINGS AND NEAR-RINGS

  • Cho, Yong-Uk
    • The Pure and Applied Mathematics
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    • v.10 no.3
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    • pp.177-183
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    • 2003
  • In this paper, we initiate the study of some annihilator conditions on polynomials which were used by Kaplansky [Rings of operators. W. A. Benjamin, Inc., New York, 1968] to abstract the algebra of bounded linear operators on a Hilbert spaces with Baer condition. On the other hand, p.p.-rings were introduced by Hattori [A foundation of torsion theory for modules over general rings. Nagoya Math. J. 17 (1960) 147-158] to study the torsion theory. The purpose of this paper is to introduce the near-rings with Baer condition and near-rings with p.p. condition which are somewhat different from ring case, and to extend a results of Armendariz [A note on extensions of Baer and P.P.-rings. J. Austral. Math. Soc. 18 (1974), 470-473] and Jøndrup [p.p. rings and finitely generated flat ideals. Proc. Amer. Math. Soc. 28 (1971) 431-435].

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Species and Macroscopic Analysis of Log Piles Used for the ex-Government General of Chosun Building (구 조선총독부 청사 (구 중앙청) 기초말뚝 통나무의 수종과 재질)

  • Park, Won-Kyu;Kim, Yo-Jung
    • Journal of Conservation Science
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    • v.9 no.1
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    • pp.48-52
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    • 2000
  • A hundred wooden foundation piles were found underground during reconstruction for Heungreamun after removing ex-Chosunchongdokbu (ex-Government General of Chosun) building, which was built in 1916, at Kyungbok Palace in Seoul. It is known that larch piles had been collected from the Yaru area near Mt. Baekdu (Changbai). in North Korea. We examined 15 piles for identification of the species and their tree-ring structure. The species is identified as Larix gmelini by microscopic observation. Average diameter of the piles was 27 cm and average age 103 years. We obtained 151 year tree-ring chronology. However, we could not date the exact cutting years because there was no reference chronology yet. When we can obtain chronologies from living trees near the Yaru area, we could make a absolute and longer chronology for studying past history and environments around Mt. Baekdu.

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A Study on the Hierarchy in Spatial Configuration of Geriatrics Hospital (노인전문병원 평면구조의 위계에 관한 연구)

  • Lee, Heang-Woo;Kim, Suk-Tae
    • Korean Institute of Interior Design Journal
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    • v.18 no.5
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    • pp.183-190
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    • 2009
  • Increase in the elderly population has given rise to various social problems throughout Korean society, and what is more, although the greater demand of medical treatment, its development is still in its early stages. Given that Specialized Geriatrics Hospital has stood amid a range of spatial complication and it should faithfully reflect the needs of elderly population, we need a better understanding of Specialized Geriatrics Hospital. This study suggested the foundation to plan of Specialized Geriatrics Hospital through analyzing and evaluating spatial configuration of Specialized Geriatrics Hospital by "Space Syntax" and "J-Graph" The study focused on Specialized Geriatric Hospitals existing in Korea which owned more than 100 beds. The result of this study is summarized as follows; First, the rate of separated convex showed that the portions of the Treatment of outpatients and Supply have increased, but onthe other hand the portion of the The ward has been on the decrease. Second, in the case of Treatment of outpatients, it was structured Tree-shaped and the Tree-shaped could be separated with two types: waiting room and wailing room with lounge. in the case of The ward, it was structured Tree-shaped and also Ring-shaped. The more recently opened Geriatrics Hospital, the closer to Ring-shaped. Third, the access to the Ccentral treatment was low though the access to the core of the each floor was high. Fourth, in the progress of intelligibility, the fact that its value has decreased is becoming a serious problem of medical development for the elderly population finally, according to J-graph's analysis, the hallway made the spatial depth of rooms and public space more deepened. This caused by scattered arrangement of public spaces. As the only planning were considered in this study, It therefore needs more diversified approaches considering physical factors such like real distance and area.

Characteristics of Shear Behavior According to State of Particle Bonding and Crushing (입자 결합 및 파쇄 형태에 따른 전단거동 특성)

  • Jeong, Sun-Ah;Kim, Eun-Kyung;Lee, Dong-Seok;Lee, Seok-Won
    • Proceedings of the Korean Geotechical Society Conference
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    • 2010.03a
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    • pp.314-323
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    • 2010
  • Recently, granular soils having a large particle size are frequently used as a filling material in the construction of foundation, harbor, dam, and so on. The shear behavior of this granular soil plays a key role in the stability of structures. For example, soil particle crushing occurring at the interface between structure and soil and/or within soil mass can cause the disturbance of ground characteristics and consequently induce an issues in respect of stability of structures. In order to investigate the shear behavior according to an existence and nonexistence of particle crushing, numerical analyses were conducted by using the DEM(Discrete Element Method)-based software program PFC(Particle Flow Code). Using the crushing model and non-crushing model which were created in this study, numerical analyses of ring shear test were conducted and their results were analyzed and compared. In general, landslide and slope stability are accompanied by a large displacement and consequently not only a peak strength but also a residual strength are very important in the analysis of landslide and slope stability. However the direct shear test which has been commonly used in the determination of shear strength parameters has a limitation on displacement therefore the residual strength parameters can not be obtained. The characteristics of residual shear behavior were investigated through the numerical analyses in this study.

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Suppression of tension variations in hydro-pneumatic riser tensioner by using force compensation control

  • Kang, Hooi-Siang;Kim, Moo-Hyun;Bhat Aramanadka, Shankar S.;Kang, Heon-Yong;Lee, Kee-Quen
    • Ocean Systems Engineering
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    • v.7 no.3
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    • pp.225-246
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    • 2017
  • Excessive dynamic-tension variations on the top-tensioned risers (TTRs) deteriorate the structural integrity and cause potential safety hazards. This phenomenon has become more remarkable in the development of deep-water fields with harsher environmental loads. The conventional prediction method of tension variations in hydro-pneumatic tensioner (HPT) has the disadvantage to underestimate the magnitude of cyclic loads. The actual excessive dynamic tension variations are larger when considering the viscous frictional fluid effects. In this paper, a suppression method of tension variations in HPT is modeled by incorporating the magneto-rheological (MR) damper and linear-force actuator. The mathematical models of the combined HPT and MR damper are developed and a force-control scheme is introduced to compensate the excessive tension variations on the riser tensioner ring. Numerical simulations and analyses are conducted to evaluate the suppression of tension variations in HPT under both regular- and irregular-wave conditions for a drilling riser of a tensioned-leg platform (TLP). The results show that significant reduction of tension variations can be achieved by introducing the proposed system. This research has provided a theoretical foundation for the HPT tension control and related structural protection.

The Surrealistic Formative Characters of Modern Costume (현대복식의 초현실주의적 조형성)

  • 형승희;은영자
    • The Research Journal of the Costume Culture
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    • v.2 no.2
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    • pp.415-443
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    • 1994
  • This thesis, drastically breaking from the prior form of art, searched mutual relationship between surrealism centering around surrealism which tried to liberate the spirit of humanbeing by investigating internal world of the humanbeing. That is to say, it is the purpose of this thesis to study the relationship between artistic trend and costume by grasping how the artistic trend of an age was specifically accepted and expressed to the modern costume as the foundation of fashion. Followings are the searched results for searching mutual relationship of the surrealism and modern costume. At first, surrealism made it possible from modern costume to an expression of formative art, and at the same time emerge from existed uniform costume, and thus presented new possibility to the harmony of costume and art with fresh and avant-garde sense. Second, by being applied the expressing method of depaysement which could materialize surrealistic image to the modern costume from various angels, and thus it suggested new aesthetic conception different from general conception of the traditional costume. Third, with regard to modern costume, introduction of various object due to thought of surrealism was a new and innovative attempt, and thus it suggested infinitive possibility of creation. So, it suggested that we could thrown away a fixed idea and that every objects could be moulded. As the result of the afore-said, wide application of the idea and formative feature of surrealism with regard to modern costume did not only ring the diversification and individualization of the costume escaped from the past traditional idea, but also at the same time prepared modern costume with the moment to develop as a formative arts.

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