• Title/Summary/Keyword: site condition

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A Case Study on the Field Monitoring of the Deep Rock Excavation Site in Urban Area on Severe Unbalanced Pressure Condition (편토압이 심한 도심지 대심도 암반굴착공사에서의 계측사례)

  • Kim, Tae-Seob;Kim, Woong-Kyu;Jung, Chang-Won;Han, Chul-Hee
    • Proceedings of the Korean Geotechical Society Conference
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    • 2008.10a
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    • pp.1259-1267
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    • 2008
  • One of the most important item for insuring the stability of ground in urban deep excavation site near by major structure such as subway is displacement control of earth retaining wall. The field monitoring system is classified by two types as manual system and automatic system. The application case of latter type of field monitoring is increased because real time measurement is possible in automatic system and that is correspondent with the recent constructional trend. Though the automatic monitoring system is more useful and advanced than manual monitoring system, accuracy of the system is not verified sufficiently. It was examined that the reliance of automatic monitoring system in this paper through the comparison of monitoring result obtained one of deep urban excavation site in which the each type of monitoring system was executed concurrently. Result of the examination is that the two types of monitoring system is generally alike in view of monitoring result, so the engineering reliance of automatic system was confirmed in case site. This study was researched in restricted one case site, so it is expected more precise analysis from security of more data monitored and progressive study.

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Formation Condition and Ferroelectric Properties of Niobate Tetragonal Tungsten Bronze (TTB) Type Ferroelectrics

  • Naoki Wakiya;Wang, Ju-Kai;Kazuo Shinozaki;Nobuyasu Mizutani
    • The Korean Journal of Ceramics
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    • v.6 no.4
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    • pp.380-384
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    • 2000
  • Crystal structure of $Ba_5-5X$Y$_10/3$Nb$_10$O$_30$ was tried to determine by Rietveld analysis using powder X-ray diffraction data. This compound has tetragonal tungsten bronze (TTB) structure with general formula, (Al)$_2$(A2)$_4$(B1)$_2$(B2)$_8$(O1)$_8$(O2)$_8$(O3)$_4$(O4)$_2$(O5)$_4$(O6)$_4$. However, it was difficult to determine the distribution of Ba and Y in Al and A2 sites by the analysis only. Combination of Rietveld analysis and site potentials calculation as well as lattice energy calculations helped to determine the distribution. As the result, it was clarified that $Ba^2+$ cations occupy A2 (pentagonal tunnel site) and $Y^3+$ cations occupy Al (cubic site). The distribution of cations at each site coincides with the distribution estimated by the difference of ionic radii. This supports the formation condition of TTB which was proposed in our previous report. $Ba_5-5X$Y$_10X/3$Nb$_10$O$_30$ shows ferroelectric characteristics. In this compound, remanent polarization decreases slightly with the composition X. On the other hand, the result of crystal structure determination reveals that atomic positions along c-axis for A1, A2, B1 and B2 cations are also decreased with the composition X. This would suggest that the dependence of remanent polarization on composition X is derived by the dependence of atomic coordinates on composition X.

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Surgical Techniques of Right Lung Transplantation in Dogs (황견에서 우측폐 이식수술기에 관한 실험적 연구)

  • 이두연
    • Journal of Chest Surgery
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    • v.22 no.3
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    • pp.416-424
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    • 1989
  • We have performed eight, single transplantations of right lung in dogs from September, 1988 to March 1989 at the Thoracic & Cardiovascular Surgical department, Yonsei University, College of Medicine, Seoul, Korea. We wrapped bronchial anastomosis site with great omentum and used cyclosporin in preoperative and postoperative periods in seven cases except one. The one without wrapping the bronchial anastomotic site with omentum and using cyclosporin died due to bronchial anastomotic site rupture in postoperative fourth day. If there is no reason to choose one side over the other, we would generally choose to do left-sided transplant as this is technically somewhat easier because of the long length of recipient bronchus and the ease of clamping the left atrium proximal to the pulmonary veins. The right atrium limits the amount of left atrium that can have incorporated into the clamp proximal to the pulmonary veins on the right side. But we had chosen to do right-sided transplant of lung because we must take variable technical experiences on right sided lung transplant in dogs. We have to anastomose one of pulmonary vein and left atrial wall on right-sided transplant easily only with double ligation of one pulmonary vein because right atrium limited the clamp of left atrium proximal to pulmonary veins with decreased venous return and cardiac output in some dogs. All seven dogs with right-sided lung transplant had survived more than one day with good condition except one. The one dog have to be sacrificed to evaluate the difference between the gas analysis in pulmonary venous and arterial blood in post-operative eight hours. We found hemorrhagic pulmonary edematous changes of contralateral left lung in this dog. And also all dogs have to be sacrificed for the evaluation of surgical problems, anytime in post-operative periods without any cardiopulmonary resuscitative efforts when the general condition would be worse progressively. We found no any surgical technical errors in seven dogs except one with thrombi in suture site of left atrium. There were hemorrhagic pulmonary edematous changes of transplanted right lung in one, of contralateral left lung in one, of contralateral left lung with double ligation of its pulmonary artery in one, thrombi around left atrial sutures sites in one, multiple air leakage in one bronchial rupture in one due to rejection or infection. There were accidental extubation and delayed intubation in one and unknown cause of death in one.

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Development of Site Classification System and Modification of Site Coefficients in Korea Based on Mean Shear Wave Velocity of Soil and Depth to Bedrock (기반암 깊이와 토층 평균 전단파속도를 이용한 국내 지반분류 방법 및 지반 증폭계수 개선)

  • Kim, Dong-Soo;Lee, Sei-Hyun;Yoon, Jong-Ku
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.28 no.1C
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    • pp.63-74
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    • 2008
  • Site response analyses were performed based on equivalent linear technique using the local geologic and dynamic site characteristics, which include soil profiles, shear wave velocity profiles and depth to bedrock for 125 sites collected in Korean Peninsula. From the results of site response analyses, 2-parameters site classification system based on the combination of mean shear wave velocity of soil and depth to bedrock was newly recommended for regions of shallow bedrock depth in Korea. First, as the borders of bedrock depth (H) for site classification were determined as 10m and 20m, the soil sites were divided into 3 classes as $H_1$, $H_2$ and $H_3$ sites. And then, the 3 site classes were subdivided into 7 classes based on the mean shear wave velocity of soil ($V_{s,soil}$). The feasibility of new site classification system was verified and the representative site coefficients ($F_a$ and $F_v$) and design response spectrum were suggested by analyzing uniform trend and dispersion of site coefficients for each site class. The suggested site coefficients and the regression curves present the nonlinear characteristics of soils according to the change of rock outcrop acceleration with uniform trend effectively. From the comparison between the mean values of response spectrum which was acquired from the site response analysis and the suggested design response spectrum, there was a little difference in some of site classes and it was verified to adjust the integration interval to make it more suitable for the site condition in Korea.

Adhesive Performance of Waterproofing System on Concrete Substrate with Moisture Condition (콘크리트 표면 함수비에 따른 교면방수재료의 인장접착성능)

  • 박성기;심재원;이병덕
    • Proceedings of the Korea Concrete Institute Conference
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    • 2001.05a
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    • pp.979-984
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    • 2001
  • Poor water-proofing integrity is related to many factors : site procedure, workmanship, weather. substrate conditions, installation(including asphalt application) conditions. The evaluation of adhesive properties tested by concrete surface moisture and asphalt application was based on laboratory test and observations. This report describes the pull-off test results of waterproofing systems currently used for installing and reparing for concrete bridge decks. The test results showed that the moisture condition fully affected the adhesive properties of sheet membranes and sealer but partially for liquid membranes.

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Application of Automated Measuring System for the Underground Construction in Urban Area (도심지 근접시공의 자동계측응용)

  • 남순성;정상용
    • Explosives and Blasting
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    • v.15 no.2
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    • pp.53-72
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    • 1997
  • It is impossible to precat the behavior of ground soil and structure accurately during underground construction in urban area or excavation in soft ground area because of difference between the assumed design condition and the actual site condition. Therefore, it must be managed by measuring system and correct the difference by real data. Large scale under ground construction in urban area like a seoul subway project has needed for Intelligent Construction technique, a field of the Engineering Contractor. The automated measuring system is developed for the technique. It is described that the procedure and the method of measuring work with application of the automated measuring system.

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Investigation Study on Noise and Vibration Condition in Construction Site (건설공사장 소음.진동 실태조사에 관한 연구)

  • Sun, Hyo-Sung;Park, Young-Min;Jo, Youn-Hee
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2008.04a
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    • pp.879-881
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    • 2008
  • The construction noise and vibration is a serious social problem in the downtown. This results in many expenses and delays of construction process because of the satisfactory settlement of popular complaints. In this study, we analyze the dispute mediation cases on the damages of construction noise and vibration and the noise and vibration condition in construction sites by using questionnaire surveys.

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Realization of Remote Condition Monitoring System for Check Valve (체크밸브의 원격 상태감시 시스템 구현)

  • Lee Seung-Youn;Jeon Jeong-Seob;Lyou Joon
    • Journal of Institute of Control, Robotics and Systems
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    • v.11 no.8
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    • pp.662-668
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    • 2005
  • This paper presents a realization of check valve condition monitoring system based on fault diagnosis algorithm and Fieldbus communication. We first acquired AE(acoustic emission) sensor data at the check valve test loop, extract fault features through the teamed neural network, and send the processed data to a remote site. The overall system has been implemented and experimented results are given to show its effectiveness.

Effect of Cupric Ion on the PSII Activity in Isolated Chinese Cabbage Chloroplasts (배추 엽록체의 광계II 활성에 미치는 구리이온의 영향)

  • 박인호
    • Journal of Plant Biology
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    • v.30 no.3
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    • pp.181-187
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    • 1987
  • Copper inhibited PSII-mediated O2 evolution (H2OlongrightarrowDCIP, H2OlongrightarrowSiMo) but not PSImediated O2 uptake(DCIP. Asc.longrightarrowMV) in isolated Chinese cabbage chloroplasts. Copper toxicity on PSII-mediated O2 evolution was higher at alkaline condition than at acidic condition and was inhanced by light illumination after copper treatment. The increased toxicity by light illumination was not recovered by subsequent dark treatment. The inhibitory effect of copper on H2OlongrightarrowDCIP reaction was higher than that on H2OlongrightarrowSiMo reaction. This result suggests that there may be another inhibitory site of copper on PSII other than water oxidizing side of PSII.

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Natural Ripening versus Artificial Enhancing of Silty Reclaimed Tidal Soils for Upland Cropping Tested by Profile Characterization

  • Ibrahim, Muhammad;Han, Kyung-Hwa;Lee, Kyung-Do;Youn, Kwan-Hee;Ha, Sang-Keun;Zhang, Yong-Seon;Hur, Seung-Oh;Yoon, Sung-Won;Cho, Hee-Rae
    • Korean Journal of Soil Science and Fertilizer
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    • v.45 no.1
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    • pp.9-15
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    • 2012
  • This study was performed to produce basic data for silty reclaimed tidal lands and to develop techniques of environmentally-friendly utilization in agricultural system. We chose the two sites in Saemangeum reclaimed tidal lands, one (Site I) has been treated with cultivating green manure and conducting the desalinization process through submergence since April, 2007 and the other (Site II) has been under natural condition without artificial treatment. In situ and ex situ physic-chemical properties were determined and comparisons were made for soil profiles examined at these two sites in April 2009. Surface soil of Site I had lower EC and higher field saturated hydraulic conductivity than those of Site II, uncultivated land. Especially, exchangeable sodium content was lowest in Site I Ap1 layer than in other layers. This is probably due to flooding desalination and green manure cultivation. Besides, Ap1 and A2 layers of soil profile in Site I showed brighter soil color and more root observation than those of Site II. This is probably due to green manure cultivation. By the large, for high cash upland crops and intensive agricultural use of silty reclaimed tidal land, site-specific soil ripening such as flooding desalination and green manure cultivation could be useful.