• Title/Summary/Keyword: quality research

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Impact of Future Chinese Emissions on Ozone Air Quality and Human Health in Northeast Asia (동북아 지역에서 중국의 미래 배출량 변화가 오존농도와 보건에 미치는 영향)

  • Kim, Hyeon-Kook;Lyu, Youngsook;Woo, Jung-Hun;Hong, Sung-Chul;Kim, Deok-Rae;Seo, Jeonghyeon;Shin, Myunghwan;Kim, Sang-Kyun
    • Journal of Climate Change Research
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    • v.7 no.4
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    • pp.451-463
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    • 2016
  • We explore the impact of Chinese future air pollutant emissions on ozone air quality in Northeast Asia (NEA) and health in South-Korea using an assessment framework including ICAMS (The Integrated Climate and Air Quality Modeling System) and BenMAP (The Environmental Benefits Mapping and Analysis Program). The emissions data sets from the climate change scenarios, the Representative Concentration Pathways (RCPs) (emission scenarios, EMSO), are used to simulate ozone air quality in NEA in the current (1996~2005, 2000s), the near future (2016~2025, 2020s) and the distant future (2046~2055, 2050s). Furthermore, the simulated ozone changes in the 2050s are used to analyze ozone-related premature mortality and economic cost in South-Korea. While different EMSOs are applied to the China region, fixed EMSO are used for other country regions to isolate the impacts of the Chinese emissions. Predicted ozone changes in NEA are distinctively affected by large changes in NOx emission over most of China region. Comparing the 2020s with the 2000s situation, the largest increase in mean ozone concentrations in NEA is simulated under RCP 8.5 and similarly small increases are under other RCPs. In the 2050s in NEA, the largest increase in mean ozone concentrations is simulated under RCP 6.0 and leads to the occurrence of the highest premature mortalities and economic costs in South-Korea. Whereas, the largest decrease is simulated under RCP 4.5 leads to the highest avoided premature mortality numbers and economic costs. Our results suggest that continuous reduction of NOx emissions across the China region under an assertive climate change mitigation scenario like RCP 4.5 leads to improved future ozone air quality and health benefits in the NEA countries including South-Korea.

Evaluation of SAR Image Quality

  • Lee Young-ran;Kim Kwang Young;Kwak Sunghee;Shin Dongseok;Jeong Soo;Kim Kyung-Ok
    • Proceedings of the KSRS Conference
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    • 2004.10a
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    • pp.397-400
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    • 2004
  • Synthetic Aperture Radar(SAR) is an active micro­wave instrument that performs high-resolution observation under almost all weather conditions. Although there are many advantages of SAR instrument, many complicated steps are involved in order to generate SAR image products. Many research and algorithms have been proposed to process radar signal and to increase the quality of SAR products. However, it is hard to find research which compare the quality of SAR products generated with different algorithms and processing methods. In our previous research, a SAR processing s/w was developed for a ground station. In addition, quality assessment procedures and their test parameters inside a SAR processor was proposed. The purpose of this paper is to evaluate the quality of SAR images generated from the developed SAR processing s/w. However, If there are no direct measurements such as radar reflector or scattering field measurement values it is difficult to compare SAR images generated with different methods. An alternative procedures and parameters for SAR image quality evaluation are presented and the problems involved in the comparison methods are discussed. Experiments based on real data have been conducted to evaluate and analyze quality of SAR images.

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Assessment of Pollution Levels in the Jangsungcheon Watershed Using Load Duration Curves and Analysis of the Causes

  • Cho, Sohyun;Bak, Jonghun;Lee, Yeong Jae;Kim, Kyunghyun;Jung, Kang Young
    • Journal of Environmental Science International
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    • v.28 no.10
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    • pp.873-885
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    • 2019
  • In this study, a load duration curve was applied to the Jangseongcheon, one of the tributaries of the Yeongsan River, to assess whether the target water quality was achieved. In addition, pollution of the water body was investigated to develop and suggest the optimal management time with respect to polluted flow sections and monthly conditions. The average flow rates of sections JS1 and JS2 were $0.25m^3/s$ and $1.08m^3/s$, respectively. The BOD and T-P for water-quality standards at JS1 were rated at II, whereas the COD and TOC were rated at III, thus indicating a fair level of water quality. By contrast, the BOD at JS2 was rated at III, the T-P at IV, and the TOC at V, indicating poor water quality in this section. The load duration curve was plotted using the actual flow data measured in eight-day intervals for eight years from 2011 to 2018 at locations JS1 and JS2 in the Jangsungcheon Basin. In an assessment using the load duration curve on whether the target water quality was met at location JS1, all of the water quality parameters (BOD, COD, TOC, T-N, T-P, and SS) satisfied the target water quality. By contrast, at location JS2, parameters COD, TOC, T-N, and T-P exceeded target values by more than 50%, indicating the target water quality was not met. The discharge loads of locations JS1 and JS2 were analyzed to identify the reasons the target water quality was exceeded. Results revealed that the land system contributed considerably. Furthermore, the discharge load of JS2 accounted for more than 80% of the load on the entire basin, excluding that of JS1. Therefore, the best method for restraining the inflow of pollutants into the stream near location JS2 must be applied to manage the water quality of the Jangsungcheon.

The Evolution of Research on Quality: Papers Published in Journal of the Korean Society for Quality Management (2007-2011) (품질연구의 발전 : 2007-2011년 품질경영학회지 게재 논문을 중심으로)

  • Lee, Don-Hee;Kim, Youn-Sung;Lee, Dong-Won;Cho, Jung-Rae
    • Journal of Korean Society for Quality Management
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    • v.40 no.2
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    • pp.94-105
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    • 2012
  • The purpose of this study is to identify and classify main research streams and trends on papers published in Journal of the Korean Society for Quality Management (JOKSFQM) during a five year period, from 2007 to 2011. 228 papers published during the period were collected for the study and analyzed to classify dimensions of research in terms of research themes, methods, and industries, etc. The results of the study showed that the 28 of 36 themes, which are presented by the Korean Society for Quality Management (KSFQM), are related to quality issues and new six themes are studied. The total of 34 themes is classified into seven research categories based on previous studies as follows: 32 % of process areas, 30.3% of leadership, 7.5% of customer and market focus, 5.6% of organizational performance, 6.6% of strategic planning, 1.3% of workforce, and 15.8% of other areas. The results indicate that quality related research need to reflect new demands of rapidly changing business market environment, such as innovation, ethic, and/or social responsibility, etc.

Pollution Characteristics of PM2.5 Observed during Winter and Summer in Baengryeongdo and Seoul (겨울 및 여름철 백령도와 서울에서 측정한 PM2.5 오염 특성)

  • Yu, Geun-Hye;Park, Seung-Shik;Park, Jong Sung;Park, Seung Myeong;Song, In Ho;Oh, Jun;Shin, Hye Jung;Lee, Min Do;Lim, Hyung Bae;Kim, Hyun Woong;Choi, Jin Young
    • Journal of Korean Society for Atmospheric Environment
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    • v.34 no.1
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    • pp.38-55
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    • 2018
  • Hourly measurements of $PM_{2.5}$ mass, organic and elemental carbon (OC and EC), and water-soluble ionic species were made at the air quality intensive monitoring stations in Baengryeongdo (BR) and Seoul (SL) during the winter (December 01~31, 2013) and summer (July 10~23, 2014) periods, to investigate the increase of $PM_{2.5}$ and secondary ionic species and the reasons leading to their increase during the two seasons. During winter, $PM_{2.5}$ and its major chemical species concentrations were higher at SL than at BR. Contribution of organic mass to $PM_{2.5}$ was approximately 1.7 times higher at BR than at SL, but the $NO_3{^-}$ contribution was two times higher at SL. Total concentration of secondary ionic species ($SO{_4}^{2-}$, $NO_3{^-}$, and $NH_4{^+}$) at BR and SL sites accounted for 29.1 and 40.1% of $PM_{2.5}$, respectively. However, during summer, no significant difference in chemical composition of $PM_{2.5}$ was found between the two sites with the exception of $SO{_4}^{2-}$. Total concentration of the secondary ionic species constituted on average 43.9% of $PM_{2.5}$ at BR and 53.0% at SL. A noticeable difference in chemical composition between the two sites during summer was attributed to $SO{_4}^{2-}$, with approximately twofold concentration and 10% higher contribution in SL. Low wind speed and high relative humidity were important factors in secondary formation of water-soluble ionic species during winter at SL, resulting in $PM_{2.5}$ increase. While the secondary formation during summer was attributed to strong photochemical processes in daytime and high relative humidity in nighttime hours. The increase of $PM_{2.5}$ and its secondary ionic species during the winter haze pollution period at SL was mainly caused either by long-range transport (LTP) from the eastern Chinese regions, or by local pollution. However, the increased $SO{_4}^{2-}$ and $NO_3{^-}$ during summer at SL were mainly caused by LTP, photochemical processes in daytime hours, and heterogeneous processes in nighttime hours.

A Critical Review on The Service Quality Measurement -Research Direction for Hotel Service Quality Measurement- (서비스품질 측정에 관한 비평적 고찰 -호텔 서비스품질 측정을 위한 방향 제시-)

  • 김희탁;김장하
    • Journal of Korean Society for Quality Management
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    • v.26 no.4
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    • pp.29-50
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    • 1998
  • The purpose of this study is to critically review the previous research on the measurement of service quality, and to present future research directions on hotel service quality measurement as follows: 1. As Carman(1990) shows in his study, items of quality measurement should be developed to be fit for the measurement of hotel service quality. 2. To evaluate the service quality of a hotel, measuring three divisions(Room, F&B and Others) separately, then combining them would be the best model. 3. Researches to identify the various dimensions of hotel service quality are needed. 4. In measuring hotel service quality, guests should be classified according to various criteria. 5. To measure the hotel service quality, SERVPERF model might be more a, pp.opriate due to the small number of items to be answered. 6. In hotel industry, researches to identify causal pths between customer satisfaction and service quality are needed. 7. We need to develop alternative scales for the measurement of hotel service quality.

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Research Trends and Instrument for Assessment in Sleep Quality (국내 수면 질 관련 양적 연구동향 및 측정도구 분석)

  • Son, Youn-Jung;Park, Jin-Hee;Youn, Heun-Keung;Kim, Sun-Hee
    • Korean Journal of Adult Nursing
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    • v.21 no.6
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    • pp.691-704
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    • 2009
  • Purpose: The purpose of this study was to identify the research trends and instruments for assessment of sleep quality in Korea. Methods: 66 quantitative research reports published from 2000 to March 2009 in Korea were selected from 5 databases: RISS4U, KISS, KISTI, DBpia, and the National Assembly Library and were analyzed according to criteria such as publication years, type of journal, participants, study fields, research design, participants, key words and instruments for assessment. Results: Research in sleep quality has been rapidly increasing in recent years. More than half of the research analyzed was conducted in nursing. The majority of research methods were survey and correlational research. Patients with chronic illness and the elderly were the major subjects in those researches. Most research was performed based on hospitals and communities. The types of variables tested for their relation and influence on sleep quality were quite limited. With respect to the instrument used for assessing sleep quality, most studies did not consider whether or not the validity of their instrument had been established. Conclusion: It is recommended to conduct clinically applicable interventional research with an experimental design and to develop a reliability and validity established sleep quality instrument for Koreans.

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Short-Term Water Quality Prediction of the Paldang Reservoir Using Recurrent Neural Network Models (순환신경망 모델을 활용한 팔당호의 단기 수질 예측)

  • Jiwoo Han;Yong-Chul Cho;Soyoung Lee;Sanghun Kim;Taegu Kang
    • Journal of Korean Society on Water Environment
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    • v.39 no.1
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    • pp.46-60
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    • 2023
  • Climate change causes fluctuations in water quality in the aquatic environment, which can cause changes in water circulation patterns and severe adverse effects on aquatic ecosystems in the future. Therefore, research is needed to predict and respond to water quality changes caused by climate change in advance. In this study, we tried to predict the dissolved oxygen (DO), chlorophyll-a, and turbidity of the Paldang reservoir for about two weeks using long short-term memory (LSTM) and gated recurrent units (GRU), which are deep learning algorithms based on recurrent neural networks. The model was built based on real-time water quality data and meteorological data. The observation period was set from July to September in the summer of 2021 (Period 1) and from March to May in the spring of 2022 (Period 2). We tried to select an algorithm with optimal predictive power for each water quality parameter. In addition, to improve the predictive power of the model, an important variable extraction technique using random forest was used to select only the important variables as input variables. In both Periods 1 and 2, the predictive power after extracting important variables was further improved. Except for DO in Period 2, GRU was selected as the best model in all water quality parameters. This methodology can be useful for preventive water quality management by identifying the variability of water quality in advance and predicting water quality in a short period.

A Study on the Establishing Efficient System for the Control of Quality Records (품질기록(品質記錄) 관리(管理)를 위한 효율적(效率的)인 System 수립(樹立) 방안(方案))

  • Lee, Sang-Bok;Kim, Young-Sea;Hong, Kyung-Sik
    • Journal of Korean Society for Quality Management
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    • v.23 no.2
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    • pp.103-112
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    • 1995
  • This paper describes the method of establishing efficient system for the control of quality records. To establish the best control system of quality records, the organization must not only understand ISO Code requirements for quality record complectly but also identify the documents to be controlled as a quality records correctly. In addition, when establishing the system, the organization must absolutely consider the fact that quality records shall be maintained to demonstrate conformance to specified requirements and the effective operation of the quality system. This will provide the guidance which need to establish the system for quality control to the organization which produces documents in accordance with ISO Code requirements.

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Analysis of Aerosol Optical Properties for High Particulate Matters and Light Asian Dust in Seoul Using GOCI (GOCI 자료를 이용한 서울 지역 고농도 미세먼지와 옅은 황사 시 에어로졸 광학적 특성 분석)

  • Kim, Deok-Rae;Choi, Won-Jun;Choi, Myungje;Kim, Jiyoung;Cho, Ara;Kim, Sang-Kyun;Kim, Jhoon;Moon, Kyung-Jung
    • Journal of Korean Society for Atmospheric Environment
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    • v.33 no.3
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    • pp.233-240
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    • 2017
  • To distinguish between high particulate matter (HPM) and light Asian dust (LAD) events, aerosol optical properties from GOCI were investigated in Seoul from 2014 to 2016. The poor air quality case caused by fine atmospheric particulate matter (i.e., 80<$PM_{10}$<$400{\mu}g/m^3$) is clearly separated from the case of heavy Asian dust that generally shows the $PM_{10}$ concentration more than $400{\mu}g/m^3$. In this study, we have found eight cases for the poor air quality and divided them into the two events(i.e., HPM and LAD). In case of aerosol optical depth (AOD), there was no big difference between two events. However, Angstrom exponent (AE) for HPM events was greater than 1, while that for LAD events less than 1. As a result of comparing aerosol type, non-absorbing fine mode aerosols were dominant for HPM events, but coarse and absorbing coarse mode aerosols for LAD events. Therefore, AE and aerosol type from GOCI can be used to distinguish between two events effectively.