• 한국지반환경공학회 논문집
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• 제9권3호
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• pp.11-15
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• 2008

대구경 상수도 관로는 제작 및 경제성 요인에 의해 주로 강관을 사용해 오고 있다. 상수도시설기준(건교부, 1992)에 강관두께를 결정하는 기준을 제시하고 있다. 그러나, 이 기준에는 강관 두께를 결정하는 체계적인 기준이 없다. 그래서, 매설관로에는 적용이 부적합한 Stewart 공식을 적용하여 강관두께를 결정해 왔다. 개정된 상수도시설기준(환경부, 1997) 에 부합되도록 지반여건과 각종응력을 고려하여 강관두께를 산정하였다. 그 결과를 기존의 방법에 의해 산정된 결과와 비교 검토한 후 최적 강관두께를 결정하는 방법을 제시하였다.

• 한국환경보건학회지
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• 제2권1호
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• pp.29-31
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• 1975

This experiment Was carried out under two points of view, from May 1st to the end of 1973. One was the comparative determination of the activation factor of Lead dioxide by kinds in measuring of Sulfur oxides concentration by $PbO_2$ cylinder method, and the other was the comparison that result with the record of auto analyzer. Five measuring sites were selected out of Seoul City. Three kinds of Lead dioxide made in Japan (B,C and D) were compared with Standard $PbO_2$ (A for use in Determination of Sulphur in the atmosphere, purity 99% up) made in British Institution, and monthly measuring was conducted at every sampling site. The recording by auto analyzer (Beckman Model 906-A $SO_2$ Analyzer) was conducted once or twice a month for 24 hours at each sampling site during the same period. And some significant results were obtained. 1. In comparative experiments to determine the activation degree of three kinds of Lead dioxide (B,C and D), the obtained correction factor of B reagent was 1.09, 1.16 in C and 1.30 in D against Standard $PbO_2$ (A). Therefore, it should be in need of standardization or clear statement about the reagents for use, in determination sulfur oxides by $PbO_2$ cylinder method. 2. Generally, the concentration of Sulfur dioxide by wilkins' convertion method from $SO_3$ showed about 20-30% higher than those by Auto analyzer.

• 환경위생공학
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• 제1권1호
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• pp.41-46
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• 1986

This study was performed to investigate the sanitation of restaurants in Seoul Area. The subjects were 153 wet towels, 64 cold noodle soup and 190 barely tea. The results were as follows: In wet towels: The detected rate of standard plate counts was $86.9\%$ (133 samples) and average count was $1.8\times10^3/g$ $the detected rate of coliform was $37.9\%$ (58 samples) and average count by MPN method was $2.0\times10^3/100g$, the detected rate of fecal coliform was $15.7\%$ (24 samples) and average count by MPN method was $3.2\times10/100g$. In cold noodle soups: The detected rate of standard plate counts was $100\%$ (64 samples) and average count was $9.4\times10^5/ml$, the detected rate of coliform was $75\%$ (48 samples) and average count by MPN method was $6.0\times10^5/100ml$, the detected rate of fecal coliform was $51.6\%$ (33 samples) and average count by MPN method was $3.4\times10^3/100ml$. In barely tea: The detected rate of standard plate counts was $87.4\%$(166 samples) and average count was $5.8\times10^3/ml$the detected rate of coliform was $66.3\%$ (126 samples) and average count by MPN method was $3.9\times10^3/100ml$, the detected rate of fecal coliform was $32.6\%$ (62 samples) and average count was by MPN method was $4.7\times10/100ml$.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2017년도 춘계 학술논문 발표대회
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• pp.44-45
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• 2017

There are various national standards designed to test the physical properties of waterproofing materials for the respective countries based on each of their environmental parameters, variables and requirements. The problems of these standard systems can be outlined in the following: (1) there are too many test methods and criteria to satisfy in order assess one waterproofing membrane system, and (2) there is currently no known method to compile the separate testing results to provide a comprehensive report on waterproofing system durability. This paper outlines and compares the performance testing results of various types of asphalt waterproofing membrane systems and discusses the potentials of a complex environmental deterioration analysis method.

• 한국토양비료학회지
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• 제41권5호
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• pp.324-329
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• 2008

A coal mine drainage sludge(designated as CMDS) is mainly generated during physicochemical treatment or electrical purification of the drainage abandoned mine that include dissolved heavy metal. To understand the possibility of an application of the dehydrated CMDS as the landfill cover medium of hygienic a reclaimed ground, an laboratory experiment was performed to investigate the physicochemical and geoengineering characteristics of the dehydrated CMDS. To improve the geoengineering characteristics of the dehydrated CMDS, the liquid limit, plasticity limit test, compaction method test, strength test, and hydraulic conductivity test ware performed with the lithification material mixed sludge. When the mixed ratio of the sludge and the lithification material was more than 1:06, the compaction method was A method, the moisture content less than 33.5%, the strength of mixed sludge was $8.2kg\;cm^{-2}$, the hydraulic conductivity was $2.7\times10^{-6}cm\;sec^{-1}$, the sludge was up to the landfill standard of US Environmental Protection Agency (US EPA).

• 한국환경농학회지
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• 제32권2호
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• pp.128-135
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• 2013

BACKGROUND: This study was performed to develop a single residue analytical method for new herbicide metazosulfuron in crops. METHODS AND RESULTS: Brown rice, apple, mandarin, Kimchi cabbage and soybean were selected as representative crops, and clean-up system, partition solvent and extraction solvent were optimized. Instrumental limit of quantitation (ILOQ), linearity of calibration curve and method limit of quantitation (MLOQ) were determined based on the chromatography and whole procedures. For recovery tests, brown rice, apple, mandarin, Kimchi cabbage and soybean samples were macerated and fortified with metazosulfuron standard solution at three levels (MLOQ, 10 MLOQ and 100 MLOQ). And then those were extracted with acetonitrile, concentrated, and partitioned with ethyl acetate. Then the extracts were concentrated again and cleaned-up through $NH_2$ (aminopropyl) SPE cartridge with acetone : dichloromethane (1% acetic acid) (20 : 80, v/v) before concentration and analysis with HPLC. CONCLUSION(S): ILOQ of metazosulfuron was 2 ng (S/N${\geq}$10) and good linearity was achieved between 0.05 and 12.5 mg/Kg of metazosulfuron standard solutions, with coefficients of determination of 0.9999. MLOQ was 0.02 mg/Kg. Good recoveries from 74.1 to 116.9% with coefficients of variation (C.V.) of less than 10% were obtained, regardless of sample type, which satisfies the criteria of Korea Food and Drug Administration (KFDA). Those results were reconfirmed with LC-MS (SIM). The method established in this study is simple, economic and efficient to be applied to most of crops as an official and general method for residue analysis of metazosulfuron.

• 한국환경과학회지
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• 제13권7호
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• pp.637-643
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• 2004

A new method of automatic recording raingauge is developed to measure rainfall with 0.01mm resolution. This use two different signals to measure rainfall more accurately compare than other raingauges. One is weight of the tipping bucket with rainfall amount and the other is pulse from tipping bucket reverse. New method applied 1 mm tipping bucket mechanism and install loadcell under tipping bucket mechanism for measuring rainfall weight. Loadcell measure weight of rainfall until 1 mm with 0.01 mm resolution and more than 1 mm than bucket reverse and pulse signal generate, after that loadcell measure weight again. The validation of new instrument was examined in the room 65 mm/hour rainfall rate total 53 mm range. There is below than 1 % error of absolute rainfall amount and 0.01 mm resolution. The field test of instrument was carried out by comparing its measured values with values recorded by weight type and standard type on June 1 2003 at Terrestrial Environmental Research Center at Tsukuba University in Tsukuba of Japan, when it has recorded total amount of 40.58 mm rainfall by standard raingauge and new raingauge recorded 41.032 mm. Same rainfall intensity pattern observed in field observation with weight type raingauge. Rainfall intensity between weight type and Lee-A type raingauge reached 0.9947 correlation in 3 minute average.

• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• 제3권3호
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• pp.151-158
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• 1999

Biogenic source emissions refer to naturally occuring emissions from vegetation, microbial activities in soil, lightening, and so on. Vegetation is especially known to emit a considerable amout of volatile organic compounds into the atmosphere. Therefore, biogenic source emissions are an important input to photochemical air quality models. since most biogenic source emissions are calculated at the county-level, they should be geographically allocated to the computational grid cells of a photochemical air quality model prior to running the model. The traditional method for the spatial allocation for biogenic source emissions has been to use a "spatial surrogate indicator" such as a county area. In order to examine the applicability of such approximations, this study developed more detailed surrogate indicators to improve the spatial allocation method for biogenic source emissions. Due to the spatially variable nature of biogenic source emissions, Geographic Information Systems(GIS) were introduced as new tools to develop more detailed spatial surrogate indicators. Use of these newly developed spatial surrogate indicators for biogenic source emission allocation provides a better resolution than the standard spatial surrogate indicator.indicator.

• 한국측량학회지
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• 제16권1호
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• pp.59-66
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• 1998

생활 수준의 향상으로 환경의 질에 대한 주민들의 관심이 높아짐에 따라 쓰레기 매립지와 같은 환경 혐오시설의 부지 선정 문제가 사회 문제로 대두되고 있다. 따라서 본 연구에서는 다량의 환경학적 정보를 저장, 관리, 분석, 표시할 수 있는 GSIS와 의사 결정 과정에서 사용될 수 있는 AHP를 이용하여 쓰레기 매립지를 평가하는 방법을 연구하고자 한다. AHP는 관계 집단들의 의견을 적절히 반영시킬 수 있는 유연성을 가지고 있기 때문에 GSIS와 연관시켜 사용하면 환경 혐오시설의 부지 선정 문제에 매우 유용하리라 생각된다.

• 분석과학
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• 제31권3호
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• pp.134-142
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• 2018

The uranium isotopic ratio in environmental samples around nuclear facilities is important because it reveals information regarding illegal activities or anthropogenic pollution. Determination of uranium isotopes, however, is a challenging task requiring much labor and time because of the complex separation procedures and lengthy process. In this study, a rapid determination method for uranium isotopes in environmental samples was developed using. The sample was completely decomposed using the alkali fusion method. The separation procedure using extraction chromatography (UTEVA) was simplified in a single step without any further removal process for Si and major matrix elements. The established method can be completed within 3 h from sample dissolution to ICP-MS measurement. Most matrix elements and uranium isotopes in the soil samples were well separated and purified. Five types of were used to assess the method's accuracy and precision for a rapid uranium analysis method. The analytical accuracy for all CRM samples ranged from 95.1 % to 97.8 %, and the relative standard deviation was below 3.9 %. From the analytical results, one may draw conclusions that the evaluated method for uranium isotopes using alkali-fusion, the extraction chromatography process, and ICP-MS measurements is fast and fairly reliable owing to its recovering efficiencies. Thus, it is expected that the evaluated method can contribute to the improvement of environmental monitoring ability.