• 제목/요약/키워드: Concentration History

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General Introduction of American Ginseng Indigenous in USA and Canada

  • Park, Chung-Heon;Bang, Kyung-Hwan;Park, Chun-Geun;Sung, Jung-Sook;Song, Won-Seob
    • Plant Resources
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    • 제6권3호
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    • pp.165-169
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    • 2003
  • American ginseng (Panax quinquefolium) is herbaceous perennial plants indigenous to North American forests. This is highly valued as medicinal herbs with a long history of collection from wild populations since 1716. Wild American ginseng distributed from Quebec in Canada to northern Florida in USA. A heavy concentration is found in the Appalachian mountains, although wild American ginseng is considered endangered. The price paid for field cultivated ginseng has dropped dramatically in the past 10 years, while the price for wild or woods cultivated ginseng has rised significantly. The price curve for ginseng resembles a roller coaster, reflecting not only supply and demand but many other factors. This information will be useful to understand American ginseng compared to Korean ginseng.

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디젤동차용 엔진 라이너 파손 원인에 관한 연구 (The Cause Analysis on Fracture of Diesel Locomotive Engine Liner)

  • 권성태;김정남
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2004년도 추계학술대회 논문집
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    • pp.674-679
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    • 2004
  • In this study, we investigated the cause analysis on fracture of diesel locomotive engine liner, which was trouble assuming the inflow of cooling water. In order to reveal the cause of fracture, we studied the use history of engine, the drawing of production appearance and the stress distribution of engine in use. Also, we conducted experiments such as tension strength test, bending test and hardness test. Next, we observed fractured sections by SEM for the purposed of explaining the fracture mechanism of engine liner. Test results showed that fracture mechanism was brittle fracture due to coarse casting structure and stress concentration caused by manufacturing badness.

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화분분석에 의한 정족산 무제치늪의 과거식생 (Past Vegetation of Moojaechi on Mt. Jungjok by Pollen Analysis)

  • 박재근;장남기
    • The Korean Journal of Ecology
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    • 제21권5_1호
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    • pp.427-433
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    • 1998
  • The standing crop and net production were estimated in Moojaechi on Mt. Jungjok. By using the decay model of organic carbon, absolute year of bog peat was calculated. Pollen analysis to bog peat revealed vegetational history and climate change around Moojaechi. The time required for amount of the accumulated peat in the bog was estimated in terms of the balance of the accumulation and decay of organic carbon of the deposit peat. Absolute year of the peat surveyed in this study was about 314 years. Pollen of Pinus was predominant in all the pollen zone, Geamineae and Cyperaceae increased in lower pollen zone while Pinus in upper pollen zone. This showes that climate of the past was probably more humid than that of present. In addition, middle pollen zone showed warming trend which is suggested by high pollen concentration of Quercus, Juglans, Carpinus and Corylus. It suggests that overall environment and vegetation were changed from warmer and more humid to dry condition in Moojaechi and it is considered as the course of boggy ground formation by retrogressive successions.

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Seismic assessment of thin steel plate shear walls with outrigger system

  • Fathy, Ebtsam
    • Structural Engineering and Mechanics
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    • 제74권2호
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    • pp.267-282
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    • 2020
  • The seismic performance and failure modes of the dual system of moment resisting frames and thin steel plate shear walls (TSPSWs) without and with one or two outrigger trusses are studied in this paper. These structural systems were utilized to resist vertical and lateral loads of 40-storey buildings. Detailed Finite element models associated with nonlinear time history analyses were used to examine seismic capacity and plastic mechanism of the buildings. The analyses were performed under increased levels of earthquake intensities. The models with one and two outriggers showed good performance during the maximum considered earthquake (MCE), while the stress of TSPSWs in the model without outrigger reached its ultimate value under this earthquake. The best seismic capacity was in favour of the model with two outriggers, where it is found that increasing the number of outriggers not only gives more reduction in lateral displacement but also reduces stress concentration on thin steel plate shear walls at outrigger floors, which caused the early failure of TSPSWs in model with one outrigger.

1945년 이후 한국병원건축 병동부의 변화 (Change of Ward Design in Korean Hospital Architecture since 1945)

  • 유영민
    • 의료ㆍ복지 건축 : 한국의료복지건축학회 논문집
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    • 제22권4호
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    • pp.67-77
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    • 2016
  • Purpose: This paper aimis to analyze the characteristics of ward plan of Korean hospital architecture constructed in each periods and identify the change since 1945. Methods: Literature review was conducted while ward plans for analysis were sellected. And then the important points of ward design were analyzed in each periods. Results: The important points of ward design - type of corridor in ward plan, number of beds per nursing unit, location of nurse station, organization of multi-bed rooms, location of patient toilet, number of day room, concentration and separation of elevator halls for patient and general- were analyzed and the characteristics of change were identified in each periods. Implications: This paper could be a basic data for arranging the history of hospital architecture in Korea.

엔터테인먼트 요소 구분을 통한 상업시설 공간계획에 관한 연구 (A Study on the Plan of Entertainment Commercial Center by Analyzing the Entertainment Factors)

  • 최은희
    • 한국실내디자인학회:학술대회논문집
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    • 한국실내디자인학회 2008년도 춘계학술발표대회 논문집
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    • pp.97-100
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    • 2008
  • Commerce has been taking a part of important on composing structure and system, having been started with simple role on exchange goods. In this point, We can say that commerce is the condensation of life based on understanding human cultures. Commercial center has been changing on a form as well as a function all through the history, following the changes of society. The attentional point is that there are always entertainment factors and have the relationship with space of the building in constant The purpose of comsume is not only just for a product but also enjoy consuming time and space. Most people have concentration spending their free time city where they live. This study identify the entertainment factors for a commerce an entertainment center.

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현대 패션디자인의 금속소재 연구 -모드사적 분석과 조형성를 중심으로- (Study on Metal material in Contemporary Fashion -Focus on analysis of mode history and the normativeness-)

  • 이영재
    • 한국의류학회지
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    • 제26권5호
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    • pp.582-593
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    • 2002
  • Metal materials have been used in the clothing design on the spirit of ingenious experiment by fashion designers, and they have been put to practical use by several designers who work out a scheme of popular fashion merchandise. This current starting from the 1960s was weakened in the 1980s, but it was appeared with various shapes of metal materials in the 1990s due to a popularity of techno/cyber fashion. Recently, textile engineering technology causes to develop new-materials which are practical and sanitary. The development of fashionable metal materials brings about the popularization of fashion with metal materials, and it induces that mainstream of modem fashion has been changed into designers of pursuing the spirit of ingenious experiment. This study examines the formative characteristics of metal materials that are based on the spirit of ingenious experiment. As a result, it is evaluated that the formative of metal materials shown in modern fashion is futurism, visual concentration, avast-garde, resistance, precious.

WRAP-SALT를 이용한 저수지 염분 추적 (Salinity Routing Through Reservoir using WRAP-SALT)

  • 이치헌;고택조
    • 한국수자원학회:학술대회논문집
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    • 한국수자원학회 2012년도 학술발표회
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    • pp.221-221
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    • 2012
  • The WRAP-SALT (Water Rights Analysis Package-SALT) simulation includes computation of end-of-month reservoir storage concentrations and mean monthly reservoir outflow concentrations for each month of the simulation. The model computes reservoir storage loads and concentrations based on load balance accounting algorithms and computes concentrations of water released and withdrawn from a reservoir as a function of the volume-weighted mean concentration of the water stored in the reservoir in the current month or previous months. A load budget accounting of the various component load inflows and outflows entering and leaving a reservoir is performed. A time history of storage concentrations computed for previous months is maintained for use in the lag procedure. This study presents computational methods for routing salinity through reservoirs for incorporation into WRAP-SALT simulation routines and methods for determining values for the parameters of the routing methods.

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Screening of Inhibition Activity of LPS-induced NO Production by Ethanol Extracts from Jeju Island Native Plants and Algae

  • Go, Boram;Hyun, Ho Bong;Yoon, Seon-A;Oh, Dae-ju;Yoon, Weon-Jong;Ham, Young-Min
    • 한국자원식물학회:학술대회논문집
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    • 한국자원식물학회 2019년도 추계학술대회
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    • pp.77-77
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    • 2019
  • Herbal medicines have been used as a basic means of clinical trial throughout history, and traditional medicines are targeted to seek functional components. To discover new cosmetic or food ingredients among numerous natural resources from Jeju island, we screened for inhibition activity against nitric oxide (NO) production in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells. Although NO formation plays an important role to relax vascular muscles or eliminate tumors, NO produced excessively in inflammatory condition can cause metabolic diseases or inflammatory dysfunctions. Among 52 natural resources ethanol extracts, 5 extracts inhibited NO production over 25% compared to only LPS-treated control at the concentration of $100{\mu}g/mL$. In further study, we try to investigate other bio-activities and the phytochemicals of 5 different extracts as useful ingredients for cosmetics or functional foods.

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축전지 제조업에서 입사 1년 미만 남자 사원들의 연 노출 지표치에 관한 연구 (A study on lead exposure indices of male workers exposed to lead less than 1 year in storage battery industries)

  • 황보영;김용배;리갑수;이성수;안규동;이병국;김정순
    • Journal of Preventive Medicine and Public Health
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    • 제29권4호
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    • pp.747-764
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    • 1996
  • This study intended to obtain an useful information for health management of lead exposed workers and determine biological monitoring interval in early period of exposure by measuring the lead exposure indices and work duration in all male workers (n=433 persons) exposed less than 1 year in 6 storage battery industries and in 49 males who are not exposed to lead as control. The examined variables were blood lead concentration (PBB), Zinc-protoporphyrin concentration (ZPP), Hemoglobin (HB) and personal history; also measured lead concentration in air (PBA) in the workplace. According to the geometric mean of lead concentration in the air, the factories were grouped into three categories: A; When it is below $0.05mg/m^3$, B; When it is between 0.05 and $0.10mg/m^3$, and C; When it is above $0.10mg/m^3$. The results obtained were as follows: 1. The means of blood lead concentration (PBB), ZPP concentration and hemoglobin(HB) in all male workers exposed to lead less than 1 year in storage battery industries were $29.5{\pm}12.4{\mu}g/100ml,\;52.9{\pm}30.0{\mu}g/100ml\;and\;15.2{\pm}1.1\;gm/100ml$. 2. The means of blood lead concentration (PBB), ZPP concentration and hemoglobin(HB) in control group were $5.8{\pm}1.6{\mu}g/100ml,\;30.8{\pm}12.7{\mu}g/100ml\;and\;15.7{\pm}1.6{\mu}g/100ml$, being much lower than that of study group exposed to lead. 3. The means of blood lead concentration and ZPP concentration among group A were $21.9{\pm}7.6{\mu}g/100,\;41.4{\pm}12.6{\mu}g/100ml$ ; those of group B were $29.8{\pm}11.6{\mu}g/100,\;52.6{\pm}27.9{\mu}g/100ml$ ; those of group C were $37.2{\pm}13.5{\mu}g/100,\;66.3{\pm}40.7{\mu}g/100ml$. Significant differences were found among three factory group(P<0.01) that was classified by the geometric mean of lead concentration in the air, group A being the lowest. 4. The mean of blood lead concentration of workers who have different work duration (month) was as follows ; When the work duration was $1\sim2$ month, it was $24.1{\pm}12.4{\mu}g/100ml$, ; When the work duration was $3\sim4$ month, it was $29.2{\pm}13.4{\mu}g/100ml$ ; and it was $28.9\sim34.5{\mu}g/100ml$ for the workers who had longer work duration than other. Significant differences were found among work duration group(P<0.05). 5. The mean of ZPP concentration of workers who have different work duration (month) was as follows ; When the work duration was $1\sim2$ month, it was $40.6{\pm}18.0{\mu}g/100ml$, ; When the work duration was $3\sim4$ month, it was $53.4{\pm}38.4{\mu}g/100ml$ ; and it was $51.5\sim60.4{\mu}g/100ml$ for the workers who had longer work duration than other. Significant differences were found among work duration group(P<0.05). 6. Among total workers(433 person), 18.2% had PBB concentration higher than $40{\mu}g/100ml$ and 7.1% had ZPP concentration higher than $100{\mu}g/100ml$ ; In workers of factory group A, those were 0.9% and 0.0% ; In workers of factory group B, those were 17.1% and 6.9% ; In workers of factory group C, those were 39.4% and 15.4%. 7. The proportions of total workers(433 person) with blood lead concentration lower than $25{\mu}g/100ml$ and ZPP concentration lower than $50{\mu}g/100ml$ were 39.7% and 61.9%, respectively ; In workers of factory group A, those were 65.5% and 82.3% : In workers of factory group B, those were 36.1% and 60.2% ; In workers of factory group C, those were 19.2% and 43.3%. 8. Blood lead concentration (r=0.177, P<0.01), ZPP concentration (r=0.135, P<0.01), log ZPP (r=0.170, P<0.01) and hemoglobin (r=0.096, P<0.05) showed statistically significant correlation with work duration (month). ZPP concentration (r=0.612, P<0.01) and log ZPP (r=0.614, P<0.01) showed statistically significant correlation with blood lead concentration 9. The slopes of simple linear regression between work duration(month, independent variable) and blood lead concentration (dependent variable) in workplace with low air concentration of lead was less steeper than that of poor working condition with high geometric mean air concentration of lead. The study result indicates that new employees should be provided with biological monitoring including blood lead concentration test and education about personal hygiene and work place management within $3\sim4$ month.

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