• Title/Summary/Keyword: Weighted Average Concentration

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A Study on the Development Strategy of Artificial Intelligence Technology Using Multi-Attribute Weighted Average Method (다요소 가중 평균법을 이용한 인공지능 기술 개발전략 연구)

  • Chang, Hae Gak;Choi, Il Young;Kim, Jae Kyeong
    • Journal of Information Technology Services
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    • v.19 no.2
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    • pp.93-107
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    • 2020
  • Recently, artificial intelligence (AI) technologies has been widely used in various fields such as finance, and distribution. Accordingly, Korea has also announced its AI R&D strategy for the realization of i-Korea 4.0 in May 2018. However, Korea's AI technology is inferior to major competitors such as the US, Canada, and Japan Therefore, in order to cope with the 4th industrial revolution, it is necessary to allocate AI R&D budgets efficiently through selection and concentration so as to gain competitive advantage under a limited budget. In this study, the importance of each AI technology was evaluated in multi-dimensional way through the questionnaire of expert group using the evaluation index derived from the literature review From the results of this study, we draw the following implication. In order to successfully establish the AI technology development strategies, it is necessary to prioritize the cognitive computing technology that has great market growth potential, ripple effect of technology development, and the urgency of technology development according to the principle of selection and concentration. To this end, it is necessary to find creative ideas, manage assessments, converge multidisciplinary systems and strengthen core competencies. In addition, since AI technology has a large impact on socioeconomic development, it is necessary to comprehensively grasp and manage scientific and technological regulations in order to systematically promote AI technology development.

Tritium concentration in rain with seasonal variation (계절에 따른 강우중 삼중수소 함량변화)

  • Yoon, Yoon-Yeol;Kim, Kyeong-Ja;Lee, Kil-Yong;Ko, Kyung-Seok
    • Analytical Science and Technology
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    • v.23 no.2
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    • pp.161-164
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    • 2010
  • The concentration of the tritium in precipitation from 2007 to 2009 has been analyzed for using tracer of groundwater study. The samples were collected monthly at Daejeon. The tritium concentrations in precipitation were ranged from 4.2 TU to 18.6 TU. The contents were higher at spring and fall season and lower at summer and winter season. The weighted average tritium content in precipitation was $7.85{\pm}0.46\;TU$.

Analysis of Rainwater Samples in Cheju (제주도에서의 빗물 이온 농도 분석)

  • 심상규;강창희;김용표
    • Journal of Korean Society for Atmospheric Environment
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    • v.10 no.2
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    • pp.98-104
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    • 1994
  • Precipitation samples were collected at Kosan, Cheju Island over a period of 6 months An automatic rain sampler was manufactured domestically and installed at Kosan station. All samples were collected on a weekly basis. Samples were analyzed for S $O_4$$^{=}$, N $O_3$$^{[-10]}$ , C $l^{[-10]}$ , N $H_4$$^{+}$, N $a^{+}$, $K^{+}$, $Ca^{++}$, $Mg^{++}$, and pH and specific conductivity. The quality analysis of rain sample data were performed based on ion balance and specific conductivity. The pH of rain samples ranged between 4.6 to 6.6. Bicarbonate ion concentration were included in ion balance and specific conductivity calculations. The sum of cation concentrations were slightly greater than the sum of anion concentrations. Calculated specific conductivity was greater than measured specific conductivity. The most probable explanations for this discrepancy is "an anion too low or anion missing." Two criteria were used to identify outliners. They are 1) the difference between the sum of anion concentrations and cation concentration is more than 50 $\mu$eq./1 and 2) the difference between calculated and measured specific conductivity is more than 25%. Chemical analysis from several samples did not satisfy these quality control criteria. Volume weighted average concentrations were calculated. Dominant free acids in rain samples were N $a^{+}$, C $l^{[-10]}$ , S $O_4$$^{=}$, N $O_3$$^{[-10]}$ ions in order of abundance. Non-seasalt sulfate comprises 76% of total sulfate.sulfate.e.ate.e.

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Long-Term Trend Analysis and Exploratory Data Analysis of Geumho River based on Seasonal Mann-Kendall Test (계절 맨-켄달 기법을 이용한 금호강 본류 BOD의 장기 경향 분석 및 탐색적 자료 분석)

  • Jung, Kang-Young;Lee, In Jung;Lee, Kyung-Lak;Cheon, Se-Uk;Hong, Jun Young;Ahn, Jung-Min
    • Journal of Environmental Science International
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    • v.25 no.2
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    • pp.217-229
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    • 2016
  • The government has conducted a plan of total maximum daily loads(TMDL), which divides with unit watershed, for management of stable water quality target by setting the permitted total amount of the pollutant. In this study, BOD concentration trends over the last 10 years from 2005 to 2014 were analyzed in the Geumho river. Improvement effect of water quality throughout the implementation period of TMDL was evaluated using the seasonal Mann-Kendall test and a LOWESS(locally weighted scatter plot smoother) smooth. As a study result of the seasonal Mann-Kendall test and the LOWESS smooth, BOD concentration in the Geumho river appeared to have been reduced or held at a constant. As a result of quantitatively analysis for BOD concentration with exploratory data analysis(EDA), the mean and the median of BOD concentration appeared in the order of GH8 > GH7 > GH6 > GH5 > GH4 > GH3 > GH2 > GH1. The monthly average concentration of BOD appeared in the order of Apr > Mar > Feb >May > Jun > Jul > Jan > Aug > Sep > Dec > Nov > Oct. As a result of the outlier, its value was the most frequent in February, which is estimated 1.5 times more than July, and was smallest frequent in July. The outlier in terms of water quality management is necessary in order to establish a management plan for the contaminants in watershed.

Existing Population Exposure Assessment Using PM2.5 Concentration and the Geographic Information System (지리정보시스템(GIS) 및 존재인구를 이용한 초미세먼지(PM2.5) 노출평가)

  • Jaemin, Woo;Gihong, Min;Dongjun, Kim;Mansu, Cho;Kyeonghwa, Sung;Jungil, Won;Chaekwan, Lee;Jihun, Shin;Wonho, Yang
    • Journal of Environmental Health Sciences
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    • v.48 no.6
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    • pp.298-305
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    • 2022
  • Background: The concentration of air pollutants as measured by the Air Quality Monitoring System (AQMS) is not an accurate population exposure level since actual human activities and temporal and spatial variability need to be considered. Therefore, to increase the accuracy of exposure assessment, the population should be considered. However, it is difficult to obtain population data due to limitations such as personal information. Objectives: The existing population defined in this study is the number of people in each region's grid. The purpose is to provide a methodology for evaluating exposure to PM2.5 through existing population data provided by the National Geographic Information Institute. Methods: The selected study period was from October 26 to October 28, 2021. Using PM2.5 concentration data measured at the Sensor-based Air Monitoring Station (SAMS) installed in Guro-gu and Wonju-si, the concentration for each grid was estimated by applying inverse distance weights through QGIS version 3.22. Considering the existing population, population-weighted average concentration (PWAC) was calculated and the exposure level of the population was compared by region. Results: The outdoor PM2.5 concentration as measured through the SAMS was high in Wonju-si on all three days. Wonju-si showed an average 22% higher PWAC than Guro-gu. As a result of comparing the PWAC and outdoor PM2.5 concentration by region, the PWAC in Guro-gu was 1~2% higher than the observed value, but it was almost the same. Conversely, observations of Wonju-si were 10.1%, 11.3%, and 8.2% higher than PWAC. Conclusions: It is expected that the Geographic Information System (GIS) method and the existing population will be used to evaluate the exposure level of a population with a narrow activity radius in further research. In addition, based on this study, it is judged that research on exposure to environmental pollutants and risk assessment methods should be expanded.

Comparing the Performance of a Deep Learning Model (TabPFN) for Predicting River Algal Blooms with Varying Data Composition (데이터 구성에 따른 하천 조류 예측 딥러닝 모형 (TabPFN) 성능 비교)

  • Hyunseok Yang;Jungsu Park
    • Journal of Wetlands Research
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    • v.26 no.3
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    • pp.197-203
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    • 2024
  • The algal blooms in rivers can negatively affect water source management and water treatment processes, necessitating continuous management. In this study, a multi-classification model was developed to predict the concentration of chlorophyll-a (chl-a), one of the key indicators of algal blooms, using Tabular Prior Fitted Networks (TabPFN), a novel deep learning algorithm known for its relatively superior performance on small tabular datasets. The model was developed using daily observation data collected at Buyeo water quality monitoring station from January 1, 2014, to December 31, 2022. The collected data were averaged to construct input data sets with measurement frequencies of 1 day, 3 days, 6 days, 12 days. The performance comparison of the four models, constructed with input data on observation frequencies of 1 day, 3 days, 6 days, and 12 days, showed that the model exhibits stable performance even when the measurement frequency is longer and the number of observations is smaller. The macro average for each model were analyzed as follows: Precision was 0.77, 0.76, 0.83, 0.84; Recall was 0.63, 0.65, 0.66, 0.74; F1-score was 0.67, 0.69, 0.71, 0.78. For the weighted average, Precision was 0.76, 0.77, 0.81, 0.84; Recall was 0.76, 0.78, 0.81, 0.85; F1-score was 0.74, 0.77, 0.80, 0.84. This study demonstrates that the chl-a prediction model constructed using TabPFN exhibits stable performance even with small-scale input data, verifying the feasibility of its application in fields where the input data required for model construction is limited.

Acidity and Chemical Composition of Precipitation at Background Area of the Korean Peninsula (Anmyeon, Uljin, Gosan) (한반도 배경지역 (안면, 울진, 고산) 상수의 산성도와 화학특성)

  • Kim, Sang-Baek;Choi, Byoung-Cheol;Oh, Suk-Yeong;Kim, San;Kang, Gong-Unn
    • Journal of Korean Society for Atmospheric Environment
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    • v.22 no.1
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    • pp.15-24
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    • 2006
  • Precipitation samples were collected at Anmyeon (1997 - 2004), Uljin, and Gosan (1998 ~ 2004), the background area of the Korean Peninsula. These samples were analyzed for the concentration of 9 major ionic components ($F^{-}$,$Cl^{-}$, $NO_{3}^{-}$, $SO_{4}^{2-}$, $Na^{+}$, $NH_{4}^{+}$, $K^{+}$, $Mg^{2+}$, $Ca^{2+}$) with including a pH and an electric conductivity. Data quality for these samples was verified by ion balance and conductivity balance which are based on GAW manual for precipitation chemistry and the number of valid data at Anmyeon, Uljin, and Gosan is 249, 173, and 188, respectively. During the study period, the precipitation-weighted average pH at Anmyeon, Uljin, and Gosan was found to be 4.81, 4.87 and 4.89, respectively and each annual average pH was showed below pH 5.6 for every site. From the frequency survey on the precipitation acidity, the occurrence rate of acid rain below pH 5.6 is greater than $80\%$ for every site. Particularly, the highest occurrence rate for strong acid rain below pH 4.5 was found at Anmyeon, $32.1\%$, compared with other sites ($10.4\%$ at Uljin, $15.4\%$ at Gosan). That's because acidifying species (nss-$SO_{4}^{2-}$, $NO_{3}^{-}$) are remarkably high concentration at Anmyeon.

The Current Work Environment Monitoring Status and Concentration Level of Substances with Short-Term Exposure Limits among Special Management Substances (특별관리물질 중 단시간노출기준 설정 물질의 작업환경측정 현황 및 농도 수준)

  • Hyunhee Park;Jihoon Jo
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.34 no.3
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    • pp.262-278
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    • 2024
  • Objectives: To investigate the work environment measurement (WEM) status and concentration levels of substances with short-term exposure limits (STEL) among special management substances. Methods: Data from the past 5 years of WEM for 6 substances (1,2-dichloropropane (1,2-DCP), 1,3-butadiene, benzene, trichloroethylene (TCE), perchloroethylene (PCE) and sulfuric acid) were analyzed. The number of samples and concentration level of STEL and 8-hour TWA (time weighted average) were compared. Results: The number of STEL measurement for 1,3-butadiene, benzene, and sulfuric acid was less than 1% of the number of TWA measurement samples, while TCE, 1,2-DCP, and PCE, which are mainly used for cleaning metals, were relatively high, at 16.1%, 5.6%, and 2.2%, respectively. When comparing the concentrations of STEL with TWA on the same STEL measured workers (STEL-matched TWA), STEL concentrations were 2.8, 3.1, 2.6, 2.6 and 40.5 times higher than TWA as 1,2-DCP, benzene, TCE, PCE, and sulfuric acid. When comparing the concentration of STEL-matched TWA with the total TWA, STEL-matched TWA was 3.4, 8, 1.4, 2.0, 8.6 and 0.7 times higher for 1,2-DCP, benzene, 1,3-butadiene, TCE, PCE, and sulfuric acid, respectively. Conclusions: This study found that the workers performing irregular tasks may be exposed to higher concentrations of hazardous substances than regular workers. It is necessary to strengthen short-term exposure measurement, even for substances which STEL have not been set.

Development of an Index Model on the Information and Communication Ethics (정보통신윤리지수 모델 개발)

  • Lee, Jae-Woon;Han, Keun-Woo;Lee, YoungJun;Kim, Seong-Sik
    • The Journal of Korean Association of Computer Education
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    • v.10 no.3
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    • pp.19-29
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    • 2007
  • The informationization policies undertaken in concentration only on the national economic growth invited the unbalance between technology and social culture, displayed the serious reverse function phenomena, and these problems threatened the personal identity of individual in the cyber space. In this study, we developed an index model on the information and communication ethics where the national level of information and communication ethics can be examined. For this purpose, based on diverse previous research data, the areas of the ethical indicators in information and communication has been developed through the brain storming of the research staff. Through the consultation with experts, the feasibility and representation as index was heightened, and the weighted values to the each index was provided by the AHP method. The outcome of questionnaires from the information users and information providers (great portals) was also reflected in simple average method into the calculation of the weighted value to the each index element.

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Benzene and Leukemia: The 0.1 ppm ACGIH Proposed Threshold Limit Value for Benzene

  • Infante Peter F.
    • 대한예방의학회:학술대회논문집
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    • 1994.02a
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    • pp.681-691
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    • 1994
  • The American Conference of Governmental Industrial Hygienists (ACGIH) has proposed a threshold limit value (TLV) for benzene of 0.1 ppm. Individuals representing the American Petroleum Institute (API)and the Chemical Manufacturers Association (CMA) have argued that 1) the risk assessment by Rinsky .et al. which ACGIH partially relied upon for its proposed TLV overestimates the risk; however, at the exposures levels of interest - (e.g., 0.1 to 1.0 ppm) for establishing a benzene TLV, the Rinsky et al. assessment provides lower estimates of leukemia risk than most others; 2) ACGIH should not use the Dow study for direct observational evidence of leukemia risk associated with low-level benzene exposure because of confounding exposure; however, it is unlikely that confounding exposures played a role in the excess of leukemia demonstrated in the study, and the Dow cohort was exposed to an average benzene concentration of about 5.5 ppm benzene for 7.11 years (31:1.5 ppm-years), while some of the individuals in the study who died from leukemia were exposed to an average of only 1.0 ppm without the opportunity for highpeak exposures; 3) the Occupational Safety and Health Administration (OSHA) established an 8-hour time-weighted average (TWA) of 1.0 ppm in 1987, and there is no new evidence that would justify reducing the TWA below that level; however, the OSHA TWA of 1.0 ppm was based on economic feasibility and the level of excess risk remaining at 1.0 ppm, i.e., 10 excess leukemia deaths per 1000 workers over an occupational lifetime (45 years) according to OSHA's preferred estimate leaves behind I risk considered significant by OSHA. In addition, chromosomal studies among workers and in animals exposed to benzene indicate that low-level exposure, i.e., 1.0 ppm, is associated with elevated Cytogenetic damage. On the basis of adverse health effects data alone, in this author's opinion, it would be poor science and poor public health policy to establish a benzene TLV greater than 0.1 ppm.

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