• Title/Summary/Keyword: Mean Concentration

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A Study on the Diffusion of Atmospheric Pollutants over Taegu (대구상공에서의 대기 오염 물질 확산에 관한 연구)

  • Yun, Il-Hui;Min, Gyeong-Deok;Park, Dong-Jae
    • Journal of Environmental Science International
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    • v.3 no.3
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    • pp.241-252
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    • 1994
  • Meteorological parameters In the atmospheric boundary layer and the vertical and horizontal dispersion parameters were determined by analyzing the data obtained by the special upper-air observations of one clear day for each season from October 1991 to August 1992. The concentration of the aklospheric pollutants over Taegu was analyzed by using the application of the Gaussian diffusion model. In the diurnal variation of diffusion of atmospheric pollutants, vertical diffusion due to turbulence is active in daytime while horizontal diffusion due to wind is active in nighttime. The mean concentration of pollutants in the side of downwind is higher during the daytime than the nighttime. Thus, the height of the mixed-layer at the nighttime considered as the most important parameter of the mean concentration of pollutants. In the seasonal variation of diffusion of atmospheric pollutants, vertical diffusion due to strong solar radiation is active in summer case day, and horizontal diffusion due to strong wind is active in winter case day. In winter case day, the mean concentration of pollutants in the side of downwind is maximum in the daytime. However, in summer case day, that is maximum in the nighttime.

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Concentration of Urinary Hippuric Acid in Toluene-Exposed Workers According to the Specific Characteristic of Work

  • Kwon, Se-Young;Na, Young-Ak;Kim, Sang-Rak
    • Korean Journal of Clinical Laboratory Science
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    • v.44 no.1
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    • pp.17-23
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    • 2012
  • This study is assessed the urinary hippuric acid (HA) concentration in toluene-exposed workers. Toluene is widely used in the coating, printing, painting and petroleum industries. We analyzed the hippuric acid level of toluene-exposed workers (males: 198, females: 63) from 2008 to 2010 and examined the relationship between hippuric acid and the characteristics of their work. The measurements of the urinary hippuric acid were confirmed by high-performance liquid chromatography. Among the subjects, males had on average more work experience than females (males: 9.17 years, females: 4.45 years), but females showed a higher hippuric acid concentration levels than males (males: 0.26 g/L, females: 0.75 g/L). The mean of the HA concentration according to the age group was 0.19 g/L in 30's, 0.30 g/L in 40's, 0.54 g/L in 50's, 1.36 g/L in 60's. Those in their 60's had the highest concentration. The mean of HA concentration according to the type of work was 0.70 g/L for the coating, 0.52 g/L for the painting, and 0.16 g/L for the printing industries, revealing that the workers in the coating industry had the highest concentration. By the highest order, the mean of HA concentration by working period was as follows; less than 5 years, ${\leq}5\;years{\sim}<10\;years$. The factors that influence the HA concentration are not only how long one is exposed to toluene but also the type of work, worker's age, and their gender.

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Studies on body types by body growth and blood chemical values in the Jindo dog 1. Blood chemical values of Jindo dogs (진도견의 혈액화학치 및 성장에 따른 체형에 관한 연구 I. 진도견의 혈액화학치)

  • Kim, Woo-kwon;Lee, Jae-hong;Kim, Ja-suk
    • Korean Journal of Veterinary Research
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    • v.29 no.3
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    • pp.263-274
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    • 1989
  • The present study was conducted ill. order to get the normal blood chemical values of Korean Jindo dogs. Blood samples were taken from 160(♂34, ♀126) healthy Jindo dogs in Jindo area. The results obtained in this study were summarized as follows: 1. The mean values of serum total protein(TP), albumin(Alb) and globulin(Glb) content, cholesterol(Chole), magnesium(Mg), calcium(Ca), inorganic phosphate(P), potassium(K), sodium(Na) and chloride(Cl) concentration in the group of less than one year old were 6.64(♂6.62, ♀6.64), 3.63(♂3.57, ♀3.65) and 3.00(♂3.05, ♀2.99)g/100ml, 170.97(♂166.46, ♀172.68)mg/100ml, 1.45(♂1.43, ♀1.46), 5.76(♂5.62, ♀5.81), 4.80(♂4.95, ♀4.75), 4.84(♂4.72, ♀4.89), 148.93(♂148.79, ♀148.98) and 110.22(♂110.42, ♀110.14)mEq/L, respectively, whereas the TP, Alb and Glb content, Chole Mg, Ca, P, K, Na and Cl concentration in the group of one year old and more were 6.88(♂6.84, ♀6.89), 3.65(♂3.63, ♀3.66) and 3.23(♂3.21, ♀3.23)g/100ml, 167.48(♂173.80, ♀166.48)mg/100ml, 1.40(♂1.36, ♀1.40), 5.69(♂5.53, ♀5.71), 4.62(♂4.73, ♀4.60), 4.88(♂4.90, ♀4.87), 149.86(♂149.60, ♀149.90) and 110.03(♂110.70, ♀109.92)mEq/L, respectively. The ratios of mean serum albumin to globulin(A/G), calcium to inorganic phosphate(Ca/P) and sodium to potassium(Na/K) in the group of less than one year old were 1.21(♂1.17, ♀1.22), 1.20(♂1.14, ♀1.22) and 30.77(♂31.52, ♀30.47), respectively, whereas the A/G, Ca/P and Na/K in the group of one year old and more were 1.13(♂1.13, ♀1.13), 1.23(♂1.17, ♀1.24) and 30.71(♂30.53, ♀30.78), respectively. 2. The mean values of Alb content, Mg, Ca and K concentration, A/G and Ca/P ratio appeared to be higher in the female than in the male, whereas the reverse was the case with P concentration. No differences were found between male and female in the TP and Glb content, Chole, Na and Cl concentration and Na/K ratio. 3. The mean values of Glb content appeared to be higher in the group less than one year old than in the group of one year old and more, whereas the reverse was the case with A/G ratio. The mean values of TP and Alb content and Ca/P ratio in the age groups less than one year tended to increase with aging, whereas the reverse was the case with Ca and P concentration. No differences were found between age groups in the Mg, K, Na and Cl concentration and Na/K ratio.

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The change of air lead concentrations in litharge making and smelting industries (일부 제련 및 리사지 사업장에서 공기중 납 노출농도의 변화)

  • Choi, Jae-Wook;Kim, Nam-Soo;Cho, Kwang-Sung;Ham, Jung-O;Lee, Byung-Kook
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.20 no.1
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    • pp.10-18
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    • 2010
  • To provide necessary information for future environmental monitoring of smelting and litharge making industries in Korea, environmental monitoring dataset of air lead concentration of 4 lead industries(1 primary smelting, 2 secondary smelting and 1 litharge making industry) were analyzed from 1994 to 2007. Data were compared using geometric mean and standard deviation with minimum and maximum values according to year of measurement, type of lead industries and type of operation of lead industries. The geometric mean and standard deviation of air concentration for a total of 1140 samples in all lead industries for overall 14 years were 70.7${\mu}g/m^3$ and 5.51 with minimum of 1${\mu}g/m^3$ and maximum of 9,185 ${\mu}g/m^3$. The overall geometric means of air concentration were above the permissible exposure levels(PEL) until year of 2001 and thereafter they were remained at the level of half of PEL. The geometric means of primary smelting, secondary smelting and litharge making industry for overall 14 years were 21.7${\mu}g/m^3$(number of samples: 353), 82.5${\mu}g/m^3$(number of samples: 357) and 164.2 ${\mu}g/m^3$(number of samples: 430) respectively. In primary smelting industry, the highest geometric mean air concentration was 35.4 ${\mu}g/m^3$ in the secondary smelting operation; followed by casting operation (24.9 ${\mu}g/m^3$) and melting operation (14.9 ${\mu}g/m^3$), respectively. On the other hand, in secondary smelting industries, the highest geometric mean air concentration was 125.4${\mu}g/m^3$ in melting operation; followed by casting operation (90.5${\mu}g/m^3$) and pre-treatment operation (43.4${\mu}g/m^3$), respectively. However, in litharge making industries, there were no significant differences of geometric mean air concentrations between litharge operation and stabilizer operation. The proportion of over PEL (50${\mu}g/m^3$) was highest in litharge industry and followed by secondary smelting industries. However The proportions of over PEL(${\mu}g./m^3.$) were decreased by the years of environmental monitoring. The significant reduction of mean air lead concentration since year of 2000 was observed due to more active environmental engineering control and new introduction of new operation in manufacturing process, but may be also influenced by non-engineering method such as reduction of operation hours or reduction of exposure time during actual environmental measurement by industrial hygienist according to more strict enforcement of occupational and safety law by the government.

Characteristics of Spacio-Temporal Variation for PM10 Concentration in Busan (부산지역 PM10농도의 시간 및 공간적 변화 특성)

  • 전병일
    • Journal of Environmental Science International
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    • v.12 no.10
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    • pp.1033-1041
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    • 2003
  • Hourly data of PM10 concentration collected from nine automatic air quality monitoring stations in Busan from 1999 to 2002 were analyzed to evaluate the spatio-temporal variation and meteorological characteristics of PM10 episodes in Busan metropolitan area. Mean concentrations ranged from 47$\mu\textrm{g}$/㎥ to 77$\mu\textrm{g}$/㎥. For most stations, mean seasonal hourly concentrations are lowest in summer and highest in spring. PM10 episode above daily mean standard(150$\mu\textrm{g}$/㎥) exhibited a maximum frequency at Gamjeondong and a minimum at Dongsamdong, and a maximum in March and a minimum in July and August. The diurnal variation of PM10 episode days is strongly influenced by traffic loads and meteorological conditions.

Zinc and Copper Intake with Food Analysis and Levels of Zinc and Copper in Serum, Hair and Urine of Female College Students (도시 여대생에 있어 식품분석에 의한 아연, 구리섭취량과 혈액, 머리카락, 소변의 아연, 구리 함량에 관한 연구)

  • 손숙미
    • Journal of Nutrition and Health
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    • v.32 no.6
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    • pp.705-712
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    • 1999
  • The purpose of this study was to assess the zinc and copper nutritional status of 102 college women by measuring zinc and copper intake, hematological parameters of zinc and copper, hair zinc and urinary excretion of zinc and copper. The mean zinc intake was 5.5mg(45.8% RDA) with food analysis and 4.5mg(37.8% RDA) with computation from food composition table. The copper intake with food analysis was 2.3mg and 1.2mg with computation. Mean serum zinc concentration was 77.02ug/dl and the proportion of subjects with zinc deficiency estimated by serum zinc(<70ug/dl)was 23.0%. Mean serum copper concentration was 121.80ug/dl and 4.1% of subjects showed serum copper less than 70ug/dl, The mean ceruloplasmin concentration was 22.63mg/dl and the proportion of subjects whose ceruloplasmin was lower than 18-40mg/dl was 6.6%. The mean hair zinc of subjects was 143.8ppm and the mean hair copper was 11.2ppm. The mean urinary excretion of zinc was 0.43mg/day and the proportion of subjects with marginal deficiency estimated by urinary zinc excretion( <0.3mg/day) was 23.3%. The mean urinary copper excretion was 0.044mg/day which was within the normal range(0.01-0.06mg/day). Assessing by zinc content in hair, urine and serum, 22.9-23.3% of college women had bordeline zinc deficiency or zinc deficiency. Whereas 4.1-6.6% of college women was assessed copper deficiency estimated by serum copper and ceruloplasmin.

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Variations of the PM10 Concentrations Observed in Eleven Cities in South Korea between 1995 and 2000 (한반도 11개 도시의 1995~2000년 PM10 농도 변화 경향)

  • 진윤하;구해정;김봉만;김용표;박순웅
    • Journal of Korean Society for Atmospheric Environment
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    • v.19 no.2
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    • pp.231-245
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    • 2003
  • Hourly PM$_{10}$ concentrations measured at 11 sites in Seoul and 10 sites in the large cities over South Korea for the period from March 1995 to February 2000 are analyzed to examine annual trend and monthly variations of the PM$_{10}$ concentrations. Further analysis has been carried out by using the one year data from March 1999 to February 2000 to see the seasonal variation, diurnal variation and weekly variation of the seasonally averaged PM$_{10}$ concentrations at each site. Weekly variations of the CO concentrations at the same sites for the same one year period are compared with that of the PM$_{10}$ concentration. There is no significant annual trend in the variation of the PM$_{10}$ concentration at all the sites analyzed. The seasonal and monthly mean concentrations show a minimum concentration in summer and alternative maximum concentration in spring and winter for most sites. The diurnal variation of the seasonally averaged mean PM$_{10}$ concentrations is strongly affected by traffic loads and meteorological conditions. The weekly variation of seasonal averaged concentrations of CO and PM$_{10}$ shows a high concentration for weekdays in spring, autumn and winter while high concentration for weekends in summer.nds in summer.

Relationship between the Measurement Values of the Digital Dust Indicator and Personal Dust Sampler (Digital 분진계와 개인용 분진 포집기의 측정값의 관계)

  • Yoon, Young-No;Lee, Jeong-Joo;Chung, Ho-Keun;Choi, Ho-Chun
    • Journal of Preventive Medicine and Public Health
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    • v.20 no.2 s.22
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    • pp.255-260
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    • 1987
  • The digital dust indicator (Sibata P-5), one of the direct·reading instruments was evaluated for the respirable dust in the underground coal mine environments. As a reference, respirable dust was determined using three cyclones and/or impactors. All the tests were performed on aerosol in twenty underground coal mines. The coefficients of mass-relative concentration were $0.067{\pm}0.054$ (Mean$\pm$Standard deviation) (range: 0.006-0.172). The relationship between relative concentration and temperature was not significant statistically. Also, the relationship of relative concentration and relative humidity was not significant. Mass concentration and relative concentration were $5.31{\pm}5.22mg/m^3$ and $162{\pm}163$ CPM ($Mean{\pm}Standard$ deviation) respectively. The range of mass concentration was $1.22-22.69mg/m^3$; relative concentration 16-628 CPM. The relationship of mass concentration and relative concentration was not significant in these ranges.

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Correlation analysis of solar radiation and meteorological parameters on high ozone concentration (태양복사 및 기상요소의 고농도 오존형성에 대한 상관성 분석)

  • An, Jae Ho
    • KIEAE Journal
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    • v.12 no.6
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    • pp.93-98
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    • 2012
  • The concerns on high ozone concentration phenomenon is significantly growing in Seoul metropolitan area including the industry complex area, like Shiwha Banwol area. The aims of this research is the analysis of relationship between high concentrations of $O_3$ and solar radiation parameters in atmosphere. The understanding of the effects of solar radiation intensity, humidity, high air temperature on ozone concentration in a day is very useful to provide a direction for reducing of the high ozone concentration to a local government or a metropolitan government. The correlation analysis between maximum ozone concentration and various meteorological parameters in 2009 - 2011 carried out using IBM's SPSS program. The results showed that the mean correlations coefficient (R) between daily Ozone maximum and solar radiation resulted R = 0.64 during 2011. May - September in 10 air pollution stations. In case of correlations between daily ozone maximum and relative humidity showed negative correlation R = -0.61. The correlation analysis with mean air temperature during 1-3 PM resulted R = 0.29. This low correlation coefficient could be corrected by using of categorized data of ozone concentration. The daily maximum ozone concentration is more dependent on peak solar radiation and high air temperature during 1-3 PM than its simple daily maximum values. The results of this research would be used to develop the high ozone alert system around Seoul metropolitan area. This correlation analysis could be partially integrated to prediction of ozone peak concentration in connection with other methods like classification and regression tree(CART).

Behavior of Formaldehyde Concentration by Temperature and Humidity of Indoor and Outdoor in Underground Shopping Center and Subway(II) (지하상가 실내외 및 지하철의 온도와 습도에 따른 Formaldehyde 거동(II))

  • 권우택
    • Journal of environmental and Sanitary engineering
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    • v.9 no.1
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    • pp.67-75
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    • 1994
  • Formaldehyde has been in widespread industrial use since World War II . Numerous sources of formaldehyde are present in the indoor environment. Additionally, the current trend toward tighter, more energy efficient buildings with lower ventilation rates has led to increase concentrations of this and other pollutants generated indoors. In this paper, the field survey was carried out once a month from January to MarctL 1994 to measure indoor and outdoor formaldehyde concentration in several underground locations in Seoul. The results could be summarized as follows : 1. At Yang- jae underground shopping center, the mean formaldehyde concentration was 77.8ppb for indoor and 68.4ppb for outdoor. At Ban- po underground shopping center, it was 175.8ppb for indoor and 127.3ppb for outdoor. At Jam- shil underground shop ping center, it was 135.2ppd for indoor and 34.6ppb for outdoor. Indoor the No.2 sub way line, it was 105.6ppb. The formaldehyde concentration using Berge equation was as follows : At Yang- jae underground shopping center, the mean formaldehyde concentration was 85.99ppb for indoor and 72.75ppb for outdoor At Ban- po underground shopping center, it was 254. 17ppb for indoor and 138.14ppb for outdoor. At Jam- shil underground shopping center, it was 249.13ppb for indoor and 36.87ppb for outdoor. Indoor the No.2 subway line, it was 131.73ppb. 3, The result of correlation analysis indicated that the relationship between temperature and formaldehyde concentration is very high( $\gamma $= 0.831 ∼ 0.974). 4. Also, the relationship between humidity and formaldehyde concentration is variant ($\gamma $ = 0.246 ∼0.999). 5. The mean formaldehyde concentration indoor and outdoor Ban- po underground shop ping center and indoor Jam- shil underground shopping center and indoor the No.2 sub way line exceed the American Society of Heating, Refrigeration, Air- conditioning Engineers( ASHRAE) stflndard of 100ppb(120 $\mu $g/m$^{3}$).

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