• Title, Summary, Keyword: 입구 부

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Large scale splitter-less FFD-SPLITT fractionation: effect of flow rate and channel thickness on fractionation efficiency (대용량 중력장 SPLITT Fractionation: 분획효율에 미치는 채널 두께와 유속의 영향)

  • Yoo, Yeongsuk;Choi, Jaeyeong;Kim, Woon Jung;Eum, Chul Hun;Jung, Euo Chang;Lee, Seungho
    • Analytical Science and Technology
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    • v.27 no.1
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    • pp.34-40
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    • 2014
  • SPLITT fractionation (SF) allows continuous (and thus a preparative scale) separation of micronsized particles into two size fractions ('fraction-a' and 'fraction-b'). SF is usually carried out in a thin rectangular channel with two inlets and two outlets, which is equipped with flow stream splitters at the inlet and the outlet of the channel, respectively. A new large scale splitter-less gravitational SF (GSF) system had been assembled, which was designed to eliminate the flow stream splitters and thus is operated by the full feed depletion (FFD) mode (FFD-GSF). In the FFD mode, there is only one inlet through which the sample is fed. There is no carrier liquid fed into the channel, and thus prevents the sample dilution. The effects of the sample-feeding flow rate, the channel thickness on the fractionation efficiency (FE, number % of particles that have the size predicted by theory) of FFD-GSF was investigated using industrial polyurethane (PU) latex beads. The carrier liquid was water containing 0.1% FL-70 (particle dispersing agent) and 0.02% sodium azide (used as bactericide). The sample loading rate was varied from about 4 to 7 L/hr with the sample concentration fixed at 0.01%. The GSF channel thickness was varied from 900 to $1300{\mu}m$. Particles exiting the GSF channel were collected and monitored by optical microscopy (OM). Sample recovery was monitored by collecting the fractionated particles on a $0.45{\mu}m$ membrane filter. It was found that FE of fraction-a was increased as the channel thickness increases, and FE of fraction-b was increased as the flow rate was increased. In all cases, the sample recovery has higher than 95%. It seems the new splitter-less FFD GSF system could become a useful tool for large scale separations of various types of micron-sized particles.

Environmental Characteristics and Catch Fluctuations of Set Net Ground in the Coastal Water of Hanlim in Cheju Island I. Properties of Temperature and Salinity (제주도 한림 연안 정치망어장의 환경특성과 어획량변동에 관한 연구 I. 수온 및 염분특성)

  • KIM Jun-Teck;JEONG Dong-Gun;RHO Hong-Kil
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.31 no.6
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    • pp.859-868
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    • 1998
  • In order to investigate the relation between the marine environmental characteristics and the change of the catch in set net, the marine environment properties were analyzed by temperature and salinity observed in the western coastal area of Cheju Island from 1995 to 1996 and the results are as follows 1) Main axis of Tsushima Current appeared in the western coastal area of Cheju Island was off 2$\~$3 miles from November to May. Therefore the waters of high temperature over $14^{\circ}C$ and high salinity from $34.40\%_{\circ}$ to $34.60\%_{\circ}$ were distributed homogeneously from surface to bottom in this time. But China Coastal Waters of low salinity appeared in the Cheju Strait from June to October, surface waters became of high temperature and low salinity, and middle and bottom waters became of the temperature from 11 to $14^{\circ}C$ and the salinity over $33.50\%_{\circ}$ and then vertically sharp thermocline and halocline are formed in the western coastal area of Cheju Island. In summer, the water temperature and salinity of the surface waters in wstern coastal area of Cheju Island were lower and higher respectively than that in middle area of the Cheju Strait and the temperature and salinity of the bottom waters in this area were higher and lower, respectively than that in middle area of the Cheju Strait. Such a distribution shows a tidal front in this coastal area. On the whole year, surface temperature and salinity were from 14 to $23^{\circ}C$ and from 30.60 to $34.60\%_{\circ}$, respectively, and annual fluctuation range of temperature and salinity was within $9^{\circ}C$ and $4.00\%_{\circ}$, respectively, Thus, annual fluctuation range in this area is much narrower than that in the Cheju Strait. In bottom water, temperature ranges from 14 to $20^{\circ}C$ through the year. Thus, the fluctuation range of temperature is narrow. The low temperature of from $11^{\circ}C$ to $13^{\circ}C$ appeared in the west enterance of Cheju Strait was not shown in this coastal area. 2) The salinity of bottom water was from $33.60\%_{\circ}$ to $34.40\%_{\circ}$ in 1995, while low salinity wale. below $32.00\%_{\circ}$ appeared all depth from June in 1996. Thus, the variation of hydrographic conditions in this area is narrow in winter, and wide in summer due to the influence of China Coastal Waters. 3) In summer, surface cold water, local eddy and fronts of temperature and salinity were showed within 2 mile from the west coast of the Cheju Island due to vertical mixing by tidal current. Especially, temperature and salinity of bottom water are changed with the change of depth around Biyang-Do. Thus, the front of temperature and salinity appeared clearly between shallow area with the depth of under 10 m and deep area with of the depth of more than 50m. Surface water in outside area where high temperature and low salinity water appear intrudes between Worlreong-Ri and Geumreung-Ri. Thus, the front of temperature and salinity was made along the line that connects from this coast to Biyang-Do, The temperature of the bottom water is $2^{\circ}C$ to $4^{\circ}C$ lower than that of the surface water and its salinity is $0.02\%_{\circ}$ to $0.08\%_{\circ}$ higher than that of the surface water even in shallow area.

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A Clinical Study of Corrosive Esophagitis (식도부식증에 대한 임상적 고찰)

  • 조진규;차창일;조중생;최춘기
    • Proceedings of the KOR-BRONCHOESO Conference
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    • pp.7-8
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    • 1981
  • Authors observed clinically 34 cases of the corrosive esophagitis caused by various corrosive agents at Kyung Hee University Hospital from Aug. 1978 to Dec. 1980. The results obtained were as follows; 1. Among the 34 patients, male was 19 (55.9%) and female 15(44.1%). Most frequently found age was 3rd decade. 2. 18 cases(52.9%) came to the hospital within 24 hours after ingestion of the agents, and 13 cases(38.2%) within 2 to 7 days. 3. Seasonal distribution showed most frequently in spring(35.3%). 4. The moment of the accident was suicidal attempt in 27 cases(79.4%) and misdrinking in 7 cases(20.6%). 5. Acetic acid was a most commonly used agent, showing 23 cases(67.6%), lye and insecticides were next in order. 6. Common chief complaints were swallowing difficulty and sore throat. 7. The average hospital days was 14.8 days. 8. Esophagogram was performed between 3 to 7 days after ingestion in 13 cases(38.2 %), findings were constrictions on the 1st narrowing portion in 4 cases(30.8%) and within normal limits in 3 cases(23.1%). 9. Esophagoscopy was performed in 31 cases(91.2%) between 2 to 7 days after ingestion, which revealed edema and coating on entrance of the esophagus in 9 cases (29.0 %). Diffuse edema on entire length of the esophagus and within normal limits were next in order. 10. Laboratory results were as follows: Anemia was in 1 cases(2.9%), leukocytosis. in 21 cases (61.8%), increase ESR in 9 cases (26.5%), markedly increased BUN and creatinine in 3 cases (8.8%), and hypokalemia in 1 cases(2.9%). Proteinuria in 10 cases(29.4%) hematuria in 4 cases(l1.8%), and coca cola urine in 3 cases (8.8%). 11. Associated diseases were 3 cases(8.8%) of cancer, 1 cases (2.9%) of diabetes mellitus, and 1 cases(2.9%) of manic depressive illness. 12. Various treatment was given: Esophageal and gastric washing in 23 cases(67.6%) for the emergent treatment, antibiotics in 32 cases(94.1%), steroids in 30 cases(88.2%), bougienation in 5 cases(14.7%), hemodialysis in 1 case(2.9%), and partial esophagectomy with gastrostomy and gastroileal anastomosis in 1 cases(2.9%). 13. Serious complications were observed in 9 cases (26.5%), consisted of 6 cases(17.6%) of esophageal stricture, 1 cases(2.9%), of aute renal failure, 1 cases (2.9%) of pneu momediastinum with pneumonia, and 1 cases (2.9%) of pneumonia.

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무령왕릉보존에 있어서의 지질공학적 고찰

  • 서만철;최석원;구민호
    • Proceedings of the KSEEG Conference
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    • pp.42-63
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    • 2001
  • The detail survey on the Songsanri tomb site including the Muryong royal tomb was carried out during the period from May 1 , 1996 to April 30, 1997. A quantitative analysis was tried to find changes of tomb itself since the excavation. Main subjects of the survey are to find out the cause of infiltration of rain water and groundwater into the tomb and the tomb site, monitoring of the movement of tomb structure and safety, removal method of the algae inside the tomb, and air controlling system to solve high humidity condition and dew inside the tomb. For these purposes, detail survery inside and outside the tombs using a electronic distance meter and small airplane, monitoring of temperature and humidity, geophysical exploration including electrical resistivity, geomagnetic, gravity and georadar methods, drilling, measurement of physical and chemical properties of drill core and measurement of groundwater permeability were conducted. We found that the center of the subsurface tomb and the center of soil mound on ground are different 4.5 meter and 5 meter for the 5th tomb and 7th tomb, respectively. The fact has caused unequal stress on the tomb structure. In the 7th tomb (the Muryong royal tomb), 435 bricks were broken out of 6025 bricks in 1972, but 1072 bricks are broken in 1996. The break rate has been increased about 250% for just 24 years. The break rate increased about 290% in the 6th tomb. The situation in 1996 is the result for just 24 years while the situation in 1972 was the result for about 1450 years. Status of breaking of bircks represents that a severe problem is undergoing. The eastern wall of the Muryong royal tomb is moving toward inside the tomb with the rate of 2.95 mm/myr in rainy season and 1.52 mm/myr in dry season. The frontal wall shows biggest movement in the 7th tomb having a rate of 2.05 mm/myr toward the passage way. The 6th tomb shows biggest movement among the three tombs having the rate of 7.44mm/myr and 3.61mm/myr toward east for the high break rate of bricks in the 6th tomb. Georadar section of the shallow soil layer represents several faults in the top soil layer of the 5th tomb and 7th tomb. Raninwater flew through faults tnto the tomb and nearby ground and high water content in nearby ground resulted in low resistance and high humidity inside tombs. High humidity inside tomb made a good condition for algae living with high temperature and moderate light source. The 6th tomb is most severe situation and the 7th tomb is the second in terms of algae living. Artificial change of the tomb environment since the excavation, infiltration of rain water and groundwater into the tombsite and bad drainage system had resulted in dangerous status for the tomb structure. Main cause for many problems including breaking of bricks, movement of tomb walls and algae living is infiltration of rainwater and groundwater into the tomb site. Therefore, protection of the tomb site from high water content should be carried out at first. Waterproofing method includes a cover system over the tomvsith using geotextile, clay layer and geomembrane and a deep trench which is 2 meter down to the base of the 5th tomb at the north of the tomv site. Decrease and balancing of soil weight above the tomb are also needed for the sfety of tomb structures. For the algae living inside tombs, we recommend to spray K101 which developed in this study on the surface of wall and then, exposure to ultraviolet light sources for 24 hours. Air controlling system should be changed to a constant temperature and humidity system for the 6th tomb and the 7th tomb. It seems to much better to place the system at frontal room and to ciculate cold air inside tombs to solve dew problem. Above mentioned preservation methods are suggested to give least changes to tomb site and to solve the most fundmental problems. Repairing should be planned in order and some special cares are needed for the safety of tombs in reparing work. Finally, a monitoring system measuring tilting of tomb walls, water content, groundwater level, temperature and humidity is required to monitor and to evaluate the repairing work.

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