• Title/Summary/Keyword: Mean Concentration

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An Efficient Method Of The Suspended Sediment-Discharge Measurement Using Entropy Concept

  • Choo, Tai-Ho
    • Water Engineering Research
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    • v.1 no.2
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    • pp.95-105
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    • 2000
  • A method is presented which enables easily the computation of the suspended sediment discharge as the mean sediment concentration and mean flow velocity. This method has significant advantages over the traditional method, which principally depend on a set of measured concentration data. The method is based on both a new sediment concentration and mean sediment concentration equations which have been derived from the entropy concept used in statistical mechanics and information theory: (1) The sediment concentration distribution equations derived, are capable of describing the variation of the concentration in the vertical direction. (2) The mean concentration equation derived, is capable of calculating easily the mean concentration by using only one measured concentration in open channel. The present study mainly addresses the following two subjects : (1) new sediment concentration and mean sediment concentration equations are derived from the entropy concept : (2) An efficient and useful method of suspended sediment-discharge measurements is developed which can facilitate the estimation of suspended sediment-discharge in open channel. Flume and laboratory data are used to carry out the research task outlined above. An efficient method for determining the suspended sediment-discharge in the open channel has been developed. The method presented also is efficient and applicable in estimating the sediment transport in rivers and the sediment deposit in the reservoirs, and can drastically reduce the time and cost of sediment measurements.

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Runoff Characteristics of Nonpoint Pollutants Source in Urban Area (중소도시지역 비점오염물질의 유출 특성)

  • Lee, Geon-Jik;Seong, Jin-Uk;Park, Ju-Hyun;Joe, Gyu-Soo;Park, Je-Chul
    • Journal of Environmental Science International
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    • v.19 no.7
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    • pp.819-827
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    • 2010
  • This study was conducted to investigate runoff characteristics of non-point pollutants source at the urban area in boeun area, Chungbuk Province. The monitoring site covering the watershed of $2.11\;km^2$ contains about 40.3 % of total watershed with the urban area. The monitoring was conducted with six events for five months and Event Mean Concentration(EMC) and Site Mean Concentration(SMC) of SS, BOD, CODMn, T-N, T-P were calculated on the result of the water quality parameters. As a result of the comparion between Arithmetic Mean Concentration and Event Mean Concentration, it showed that over all Event Mean Concentration was higher than Arithmetic Mean Concentration. And it showed that SS, BOD, T-P featured the first-flushing effect, showing relatively high concentration in early-stage storm event.

Blood chemistry profiles in indigenous Korean striped calves from birth up to the age of 2 months (칡소 송아지의 생후 2개월간 혈액화학치 양상에 관한 연구)

  • Cho, Kwang-Hyun;Park, Yong-Soo;Kim, Seong-Guk;Do, Jae-Cheul;Eo, Kyung-Yeon;Kwak, Dongmi;Kwon, Oh-Deog
    • Korean Journal of Veterinary Service
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    • v.39 no.3
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    • pp.151-157
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    • 2016
  • The present study was undertaken to clarify the changes in blood chemical values of indigenous Korean striped calves according to age. Blood samples were collected from 15 calves (8 females and 7 males) reared at the Gyeongsangbukdo Livestock Research Institute and the levels of various chemicals in serum were analyzed. The mean total protein, albumin and globulin concentration in calves increased from 2 weeks after birth, and the levels in females were higher than those in males at 8 weeks after birth. The mean glucose concentration increased significantly at 2 weeks after birth. The mean blood urea nitrogen concentration increased from 2 weeks after birth, whereas the mean creatinine concentration decreased significantly from 2 weeks after birth. The mean uric acid concentration increased gradually from 2 weeks after birth. The mean glutamic oxaloacetic transaminase and glutamic pyruvic transaminase concentration increased significantly from 2 weeks after birth. The mean total bilirubin concentration tended to decrease from 2 weeks after birth. The mean triglyceride, total cholesterol and high density lipoprotein cholesterol concentration increased significantly from 2 weeks after birth. In conclusion, the data obtained from this study may be valuable as a standard for interpreting results of biochemical analyses in indigenous Korean striped calves.

Field Measurements of Indoor Air Quality in Apartment Units at Medium-size Cities (중소도시 공동주택의 실내공기질(새집증후군) 실측에 관한 연구)

  • Yoon, JaeOck
    • KIEAE Journal
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    • v.10 no.4
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    • pp.81-86
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    • 2010
  • The main sources of the new house syndrome(sometimes it called sick building syndrome) are a concentration of formaldehyde (HCHO) and a concentration of total volatile organic compounds(TVOC). I had field measurements of indoor air quality in the apartment unit at medium-size cities(Y city, C city). I measured indoor air temperature, HCHO concentration in 16 units, TVOC concentration in 6 units and air tightness in 7 units. And I measured outdoor air quality, HCHO concentration and TVOC concentration. Mean concentration of HCHO was $357{\mu}g/m^3$(2006 standard=$120{\mu}g/m^3$), mean concentration of TVOC was $3,092{\mu}g/m^3$ and mean effective air leakage area was 193 cm2. There was a close relation between the indoor air temperature and HCHO concentration, between the indoor air temperature and TVOC concentration. Air tightness also had relation.

Environmental Working Status of Mercury using Industries in Korea (수은 취급사업장 작업환경 실태에 관한 조사연구)

  • Chung, Mu Soo;Hwang, Kyu Yoon;Ahn, Kyu Dong;Lee, Byung Kook
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.1 no.2
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    • pp.128-135
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    • 1991
  • To obtain the basic information of environmental working status in mercury industries in Korea, 26 mercury industries were investigated with mercury concentration in air and various factors affecting on workplace environment. The results were as follows : 1. The mean air concentration of mercury was $0.046{\pm}0.035mg/m^3$ in 26 mercury industries. 2. The highest mean air concentration of mercury among 26 mercury industries classified by type of product was found in sodium hydroxide manufacturing industries ($0.054{\pm}0.020mg/m^3$) and the lowest mean was found in mercury battery manufacturing industries ($0.003{\pm}0.002mg/m^3$). 3. While the highest' mean air concentration of mercury was found in manual method ($0.061{\pm}0.041mg/m^3$) among the types of operation method, lowest one was found in automatic method ($0.035{\pm}0.025mg/m^3$). 4. While the mean air concentration of mercury was $0.023{\pm}0.018mg/m^3$ in good clean status of workshop, the mean air concentration of mercury in bad clean status was $0.06{\pm}0.033mg/m^3$. Among various factors affecting on th e air concentration of mercury, clean Iiness of workshop showed statistically significant difference with air concentration of mercury, and automation of workshop and local exhaust ventitlation also played important role in control the air concentration of mercury in the working environment.

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A Study on Air Pollution and Thermal Factors in Underground Shopping Center of Pusan Area (부산시내 지하생활권의 공기오염도와 온열인자에 관한 조사연구)

  • Choi, Sung-Yong;Moon, Deog-Hwan;Lee, Jong-Tae;Song, In-Hyuk;Lee, Cha-Eun;Lee, Sung-Min
    • Journal of Preventive Medicine and Public Health
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    • v.27 no.3 s.47
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    • pp.505-516
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    • 1994
  • For the purpose of preparing the fundamental data on air pollution in underground shopping center and also contributing to the health improvement of residents, the authors measured the level of $SO_2,\;NO_2,\;TSP,\;CO,\;CO_2$ and also some related factors as air temperature, air movement, relative humidity and mean radiation temperature at inside and outside of underground shopping center in Pusan from January to February and from July to August 1994. The results were as follows : 1. The mean concentration of CO within the underground shopping center was $3.1{\pm}1.3ppm$ in winter and $2.1{\pm}0.9ppm$ in summer. There was a negative correlation (p<0.01) between inner CO concentration and temperature in summer and no correlation between inner CO concentration and outer CO concentration in underground shopping center 2. The mean concentration of COE within the underground shopping center was $876{\pm}353ppm$ in winter and $757{\pm}125ppm$ in summer. There was a negative correlation (p<0.01) between inner $CO_2$ concentration and air movement in summer and positive correlation (p<0.05) between inner $CO_2$ concentration and outer $CO_2$ concentration in underground shopping center. 3. The mean concentration of $SO_2$ within a underground shopping center was $0.036{\pm}0.019ppm$ in winter and $0.040{\pm}0.013ppm$ in summer. There was a positive correlation(p<0.01) between inner $SO_2$ concentration and temperature in summer and positive correlation between inner $SO_2$ concentration and outer $SO_2$ concentration in summer and winter in underground shopping center. 4. The mean concentration of $NO_2$ within a underground shopping center was $0.052{\pm}0.038ppm$ in winter and $0.042{\pm}0.016ppm$ in summer. There was a no correlation between inner $SO_2$ concentration and thermal factors in summer and winter and low correlation between inner $SO_2$ concentration and outer $SO_2$ concentration in underground shopping center 5. The mean concentration of TSP within a underground shopping center was $430{\pm}214{\mu}g/m^3$ in winter, $366{\pm}73{\mu}g/m^3$ in summer, and very in excess of the atmospheric environmental quality standards of Korea ($150{\mu}g/m3{\downarrow}$). There was low correlation between inner TSP concentration and temperature in summer and high correlation between inner TSP concentration and outer TSP concentration in underground shopping center.

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The Concentration Ascension of Volatile Organic Compounds after Remodeling in Apartment Houses (아파트 리모델링 전.후의 휘발성유기화합물 농도 변화)

  • Choi, Yoon-Jung;Shin, Hae-Chul;Shim, Hyun-Suk
    • Proceeding of Spring/Autumn Annual Conference of KHA
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    • 2006.11a
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    • pp.287-290
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    • 2006
  • The purposes of this study were to make clear the present condition of the TVOC and HCHO concentration after remodeling in apartment houses and to analyze the relation of concentrated ascension and remodeling elements. The field measurements of TVOC and HCHO concentration were carried out in 4 subject apartment houses according to the Korea Test Method Standard for Indoor Air Quality. The results are as follows; the TVOC concentration after remodeling ranged from mean 0.35ppm to mean 5.08ppm and increased of 0.35$^{\sim}$5.08ppm. The concentration of 3 subjects exceeded the Indoor Air Quality Management standard for the newly-built apartment houses (0.7ppm). The HCHO concentration after remodeling ranged from mean 0.13ppm to mean 0.43ppm and increased of 0.06$^{\sim}$0.26ppm. The concentration of 2 subjects exceeded the Standard (0.16ppm). As results of analysis on the relation of concentrated ascension and remodeling elements, the amount and the types of finishing materials and adhesives affected concentrated ascension. Also, production method for installed or purchased furniture had certain effect on the TVOC and HCHO concentration ascension.

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The Concentration Variation of Volatile Organic Compounds before and after Renovation in Apartment Houses (아파트 개조 전후의 휘발성유기화합물 농도변화 실태)

  • Choi, Yoon-Jung;Shim, Hyun-Suk;Shin, Hae-Chul
    • Journal of the Korean housing association
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    • v.18 no.4
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    • pp.59-67
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    • 2007
  • The purposes of this study were to make clear the present condition of the TVOC and HCHO concentration after renovation in apartment houses. The field measurements of TVOC and HCHO concentration according to the Korea Test Method Standard for Indoor Air Quality were carried out in 4 subject apartment houses. The results are as follows; the TVOC concentration after renovation in apartment houses ranged from mean 0.35ppm to mean 5.08ppm and increased of $0.35{\sim}5.08ppm$. The TVOC concentration of 3 subjects exceeded the Indoor Air Quality Management standard for the newly-built apartment houses (0.58ppm). The HCHO concentration after renovation ranged from mean 0.13ppm to mean 0.43ppm and increased of $0.06{\sim}0.26ppm$. The HCHO concentration of 2 subjects exceeded the Standard (0.17ppm). As results of analysis on the relation of concentrated ascension and renovation elements, the amount and the types of finishing materials and adhesives affected concentrated ascension. Also, production method for installed or purchased furniture had certain effect on the TVOC and HCHO concentration ascension.

Analysis of BOD Mean Concentration and Confidence Interval using Bootstrap Technique (Bootstrap 기법을 이용한 BOD 평균 농도 및 신뢰구간 분석)

  • Kim, Kyung Sub
    • Journal of Korean Society on Water Environment
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    • v.26 no.2
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    • pp.297-302
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    • 2010
  • It is very important to know mean and confidence interval of water-quality constituents such as BOD for water-quality control and management of rivers and reservoirs effectively. The mean and confidence interval of BOD at Anseong2 and Hwangguji3 sampling stations which are located at the border of local governments in Anseong Stream were estimated and analyzed in this paper using Bootstrap technique which is one of non-parametric statistics. The results of Bootstrap were compared with arithmetic mean, geometric mean, Biweight method mean as a point estimator and distribution mean came from the appropriate probability distribution of Log-normal. In Bootstrap technique 12 data set was randomly selected in each year and 1000 samples was produced to get parameter of population. Visual Basic for Applications (VBA) of Microsoft Excel was utilized in Bootstrap. It was revealed that the Bootstrap technique can be used to explain more rigorously and robustly the achievement or violation of BOD target concentration in Total Maximum Daily Load (TMDL).

Seasonal Variation of Microalgae in the Surface Water of Marian Cove, King George Island, the Antarctic 1998/1999 (1998/1999 남극 킹조지섬 마리안소만 표층수에 서식하는 미세조류의 계절적 변동)

  • 강재신;강성호;이진환;최돈원;이상훈
    • Korean Journal of Environmental Biology
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    • v.18 no.1
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    • pp.21-31
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    • 2000
  • We investigated seasonal variation of microalgal assemblages, sea water temperature, salinity and suspended solid and the parameters measured daily from January 1998 to October 1999 at a nearshore shallow-water in Marian Cove, Maxwell Bay, King George Island, the Antarctic. Annual mean surface water temperature was -0.3$0^{\circ}C$ and the highest water temperature was 4.53$^{\circ}C$ (22 January 1999) and the lowest water temperature was -2.07$^{\circ}C$ (23 August 1998). Annual mean salinity was 33.38 psu, ranging from 42.80 psu (6 January 1999) to 19.50 psu (6 June 1999). Annual mean suspended solid (SS) during two years was 34.14 mgㆍ1$^{-1}$, ranging from 60.62 mgㆍ1$^{-1}$(7 March 1998) to 12.90 mgㆍ1$^{-1}$ (26 December 1998). Chlorophyll $\alpha$ (Chl $\alpha$) concentrations were measured in order to know seasonal variations of microalgae in the surface seawater. Annual mean of total Chl a concentration was 0.55$\mu\textrm{g}$ㆍ1$^{-1}$, the highest Chl $\alpha$ concentration (12.16$\mu\textrm{g}$ㆍ1$^{-1}$) appeared in 4 October 1998, the lowest Chl $\alpha$ concentration appeared 0.19$\mu\textrm{g}$ㆍ1$^{-1}$, Monthly mean total Chl $\alpha$ concentration was high in October 1998 (1.32$\mu\textrm{g}$ㆍ1$^{-1}$) and low in July on 1998 (0.28$\mu\textrm{g}$ㆍ1$^{-1}$). Annual mean nano-sized Chl $\alpha$ concentration was 0.40$\mu\textrm{g}$ㆍ1$^{-1}$, monthly mean nano -sized Chl $\alpha$ concentration was high in November 1998 (0.90$\mu\textrm{g}$ㆍ1$^{-1}$), and low in July 1999 (0.22$\mu\textrm{g}$ㆍ1$^{-1}$). Annual mean micro-sized Chl $\alpha$ concentration was 0.15$\mu\textrm{g}$ㆍ1$^{-1}$ monthly mean micro-sized Chl $\alpha$ concentration was high in October 1998 (0.81$\mu\textrm{g}$ㆍ1$^{-1}$), and low July 1998, January, February and September 1999 (0.05$\mu\textrm{g}$ㆍ1$^{-1}$). More than 65% of total Chl $\alpha$ was concentrated during spring and summer time between October and March. Microalgal variation appeared to be due to physical factors of seawater in the Antarctic nearshore from 1998 to 1999. The reason why micro-sized Chl $\alpha$ did not increase during austral summer was the bay had been frozen by decrease of water temperature. We think that total microalgal abundance was decreased because the summer microalgal abundance was determined by variation of water temperature during winter season. [Chl $\alpha$ concentration, Microalgal assembalges, Seasonal variation, the Antarctic nearshore].

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