• Title/Summary/Keyword: Deviation

Search Result 9,461, Processing Time 0.034 seconds

Introduction of GOCI-II Atmospheric Correction Algorithm and Its Initial Validations (GOCI-II 대기보정 알고리즘의 소개 및 초기단계 검증 결과)

  • Ahn, Jae-Hyun;Kim, Kwang-Seok;Lee, Eun-Kyung;Bae, Su-Jung;Lee, Kyeong-Sang;Moon, Jeong-Eon;Han, Tai-Hyun;Park, Young-Je
    • Korean Journal of Remote Sensing
    • /
    • v.37 no.5_2
    • /
    • pp.1259-1268
    • /
    • 2021
  • The 2nd Geostationary Ocean Color Imager (GOCI-II) is the successor to the Geostationary Ocean Color Imager (GOCI), which employs one near-ultraviolet wavelength (380 nm) and eight visible wavelengths(412, 443, 490, 510, 555, 620, 660, 680 nm) and three near-infrared wavelengths(709, 745, 865 nm) to observe the marine environment in Northeast Asia, including the Korean Peninsula. However, the multispectral radiance image observed at satellite altitude includes both the water-leaving radiance and the atmospheric path radiance. Therefore, the atmospheric correction process to estimate the water-leaving radiance without the path radiance is essential for analyzing the ocean environment. This manuscript describes the GOCI-II standard atmospheric correction algorithm and its initial phase validation. The GOCI-II atmospheric correction method is theoretically based on the previous GOCI atmospheric correction, then partially improved for turbid water with the GOCI-II's two additional bands, i.e., 620 and 709 nm. The match-up showed an acceptable result, with the mean absolute percentage errors are fall within 5% in blue bands. It is supposed that part of the deviation over case-II waters arose from a lack of near-infrared vicarious calibration. We expect the GOCI-II atmospheric correction algorithm to be improved and updated regularly to the GOCI-II data processing system through continuous calibration and validation activities.

Environmental Prediction in Greenhouse According to Modified Greenhouse Structure and Heat Exchanger Location for Efficient Thermal Energy Management (효율적인 열에너지 관리를 위한 온실 형상 및 열 교환 장치 위치 개선에 따른 온실 내부 환경 예측)

  • Jeong, In Seon;Lee, Chung Geon;Cho, La Hoon;Park, Sun Yong;Kim, Seok Jun;Kim, Dae Hyun;Oh, Jae-Heun
    • Journal of Bio-Environment Control
    • /
    • v.30 no.4
    • /
    • pp.278-286
    • /
    • 2021
  • In this study, based on the Computational Fluid Dynamics (CFD) simulation model developed through previous study, inner environmenct of the modified glass greenhouse was predicted. Also, suggested the optimal shape of the greenhouse and location of the heat exchangers for heat energy management of the greenhouse using the developed model. For efficient heating energy management, the glass greenhouse was modified by changing the cross-section design and the location of the heat exchanger. The optimal cross-section design was selected based on the cross-section design standard of Republic of Korea's glass greenhouse, and the Fan Coil Unit(FCU) and the radiating pipe were re-positioned based on "Standard of greenhouse environment design" to enhance energy saving efficiency. The simulation analysis was performed to predict the inner temperature distribution and heat transfer with the modified greenhouse structure using the developed inner environment prediction model. As a result of simulation, the mean temperature and uniformity of the modified greenhouse were 0.65℃, 0.75%p higher than those of the control greenhouse, respectively. Also, the maximum deviation decreased by an average of 0.25℃. And the mean age of air was 18 sec. lower than that of the control greenhouse. It was confirmed that efficient heating energy management was possible in the modified greenhouse, when considered the temperature uniformity and the ventilation performance.

Evaluation of Image Quality using SE-EPI and SSH-TSE Techniques in MRDWI (자기공명확산강조영상에서 SE-EPI 와 SSH-TSE 기법을 이용한 영상의 질 평가)

  • Goo, Eun-Hoe
    • Journal of the Korean Society of Radiology
    • /
    • v.15 no.7
    • /
    • pp.991-998
    • /
    • 2021
  • The purpose of this study is to investigate the image quality of the SE-EPI and SSH-TSE technique for MR DWI. Datum were analyzed for 35 PACS transmission datum(Normal part: 12 males, 13 females, Cerebral Infarction: 10(5males and 5females), and average age 68±7.32), randomly selected patients who underwent MRDWI tests. The equipment used was Ingenia CX 3.0T, SSH_TSE and SE-EPI pulse sequence and 32 Ch. head coil were used for data acquisition. Image evaluation was performed on the paired t-test and Wilcoxon tests, and was considered significant when the p value was 0.05 or less. As a result of quantitative analysis of SNR for DWI images, the mean and standard deviation values of 4 parts (WM, GM, BG, Cerebellum) in ADC (s/mm2), Diffusion b=0, 1000 images were higher in SE-EPI techniques(ADC: 120.50 ± 40, b=0: 54.50 ± 35.91, b=1000: 91.61 ± 36.63) than in SSH-TSE techniques(ADC: 99.69 ± 31.10, b=0: 43.52 ± 25.00 , b=1000: 60.74 ± 24.85)(p<0.05). The CNR values for GM-WM, BG-WM sites were also higher in SE-EPI technique (ADC: 116.08 ± 43.30, b=0:27.23 ± 09.10, b=1000: 78.50 ± 16.56) than in SSH-TSE(ADC: 101.08 ± 36.81, b=0: 23.96 ± 07.79 , b=1000: 74.30 ± 14.22). As a visual evaluation of observers, ghost artifact, magnetic susceptibility artifacts and overall image quality for SE-TSE and SSH-TSE all yielded high results from SSH-TSE techniques(ADC:3.6 ± 0.1, 2.8 ± 0.2, b=0: 4.3 ± 0.3, 3.4 ± 0.1 b=1000: 4.3 ± 0.2, 3.5 ± 0.2, p=0.000). In conclusion, the SE-EPI technique obtained an superiority in SNR and CNR measurements using SSH-TSE, SE-EPI. In the qualitative analysis, the SSH-TSE pulse sequence was obtained a high result according to the pulse sequence characteristics.

NOx Emission Characteristics with Operating Conditions of SNCR in SRF Usage Facilities (고형연료제품 사용시설에서의 SNCR의 운전조건에 따른 NOx 배출특성)

  • Seo, Je-Woo;Kim, Younghee
    • Clean Technology
    • /
    • v.27 no.4
    • /
    • pp.350-358
    • /
    • 2021
  • The results of this study shows that the combustor temperature ranged from 848.27 to 1,026.80 ℃, averaging about 976.61 ℃, and the NOx concentration increased as the temperature increased. The urea usage ranged from 291.00 to 693.00 kg d-1, averaging about 542.34 kg d-1, and the NOx concentration decreased as the urea usage increased. Residence time was about 3.38 to 9.17 s, averaging about 5.22 s, about 2.61 times larger than the 2 s of the design details. This is 1,086 kg h-1, averaging about 55.71%, compared to the 1,950 kg h-1 SRF input permission standard. The combustion chamber area is constant, but the residence time is shown to increase with the decrease of exhaust gas. The O2/CO ratio was 847.05 to 14,877.34, averaging about 3,111.30, and the NOx concentration slightly increased as the O2/CO ratio increased. As the combustor temperature and O2/CO ratio increased, the combustion reaction with nitrogen in the air increased and the NOx concentration slightly increased. As the urea usage and residence time increased, the NOx concentration decreased slightly with an increase in reactivity with NOx. The NOx concentration at the stack ranged from 7.88 to 34.02 ppm with an average of 19.92 ppm, and was discharged within the 60 ppm emission limit value. The NOhx emission factor was 1.058 to 1.795 kg ton-1, averaging about 1.450 kg ton-1. This value was about 24.87% of the maximum emission factor of 5.830 kg ton-1 of other solid fuels. Other synthetic resins and industrial wastes were 79.80% and 43.65% compared to 1.817 kg ton-1 and 3.322 kg ton-1, respectively. This value was similar to 1.400 kg ton-1 of RDF in the NIER notice (2005-9), 10.98% compared to the maximum SRF of 13.210 kg ton-1. Therefore, the NOx emission factor had a large deviation.

Analysis of Climate Change Researches Related to Water Resources in the Korean Peninsula (한반도 수자원분야 기후변화 연구동향 분석)

  • Lee, Jae-Kyoung;Kim, Young-Oh;Kang, Noel
    • Journal of Climate Change Research
    • /
    • v.3 no.1
    • /
    • pp.71-88
    • /
    • 2012
  • The global warming is probably the most significant issue of concern all over the world and according to the report published by the Intergovernmental Panel on Climate Change (IPCC), the average temperature and extent of global warming around the globe have been on the rise and so have the uncertainty for the future. Such effects of global warming have adverse effects on basic foundation of the mankind in numerous ways and water resource is no exception. The researches on water resources assessment for climate change are significant enough to be used as the preliminary data for researches in other fields. In this research, a total of 124 peer-reviewed publications and 57 reports on the subject of research on climate change related to water resources, that has been carried out so far in Korea has been reviewed. The research on climate change in Korea (inclusive of the peer-reviewed articles and reports) has mainly focused on the future projection and assessment. In the fields of hydrometeorology tendency and projection, the analysis has been carried out with focus on surface water, flood, etc. for hydrological variables and precipitation, temperature, etc. for meteorological variables. This can be attributed to the large, seasonal deviation in the amount of rainfall and the difficulty of water resources management, which is why, the analysis and research have been carried out with focus on those variables such as precipitation, temperature, surface water, flood, etc. which are directly related to water resources. The future projection of water resources in Korea may differ from region to region; however, variables such as precipitation, temperature, surface water, etc. have shown a tendency for increase; especially, it has been shown that whereas the number of casualties due to flood or drought decreases, property damage has been shown to increase. Despite the fact that the intensity of rainfall, temperature, and discharge amount are anticipated to rise, appropriate measures to address such vulnerabilities in water resources or management of drainage area of future water resources have not been implemented as yet. Moreover, it has been found that the research results on climate change that have been carried out by different bodies in Korea diverge significantly, which goes to show that many inherent uncertainties exist in the various stage of researches. Regarding the strategy in response to climate change, the voluntary response by an individual or a corporate entity has been found to be inadequate owing to the low level of awareness by the citizens and the weak social infrastructure for responding to climate change. Further, legal or systematic measures such as the governmental campaign on the awareness of climate change or the policy to offer incentives for voluntary reduction of greenhouse gas emissions have been found to be insufficient. Lastly, there has been no case of any research whatsoever on the anticipated effects on the economy brought about by climate change, however, there are a few cases of on-going researches. In order to establish the strategy to prepare for and respond to the anticipated lack of water resources resulting from climate change, there is no doubt that a standardized analysis on the effects on the economy should be carried out first and foremost.

Analysis of PM2.5 Concentration and Contribution Characteristics in South Korea according to Seasonal Weather Patternsin East Asia: Focusing on the Intensive Measurement Periodsin 2015 (동아시아 지역의 계절별 기상패턴에 따른 우리나라 PM2.5 농도 및 기여도 특성 분석: 2015년 집중측정 기간을 중심으로)

  • Nam, Ki-Pyo;Lee, Dae-Gyun;Jang, Lim-Seok
    • Journal of Environmental Impact Assessment
    • /
    • v.28 no.3
    • /
    • pp.183-200
    • /
    • 2019
  • In this study, the characteristics of seasonal $PM_{2.5}$ behavior in South Korea and other Northeast Asian regions were analyzed by using the $PM_{2.5}$ ground measurement data, weather data, WRF and CMAQ models. Analysis of seasonal $PM_{2.5}$ behavior in Northeast Asia showed that $PM_{2.5}$ concentration at 6 IMS sites in South Korea was increased by long-distance transport and atmospheric congestion, or decreased by clean air inflow due to seasonal weather characteristics. As a result of analysis by applying BFM to air quality model, the contribution from foreign countries dominantly influenced the $PM_{2.5}$ concentrations of Baengnyeongdo due to the low self-emission and geographical location. In the case of urban areas with high self-emissions such as Seoul and Ulsan, the $PM_{2.5}$ contribution from overseas was relatively low compared to other regions, but the standard deviation of the season was relatively high. This study is expected to improve the understanding of the air pollutant phenomenon by analyzing the characteristics of $PM_{2.5}$ behavior in Northeast Asia according to the seasonal weather condition change. At the same time, this study can be used to establish the air quality policy in the future, knowing that the contribution of $PM_{2.5}$ concentration to the domestic and overseas can be different depending on the regional emission characteristics.

A Study on Applied to Optimal Diagnostic Device in Portal Vein Visualization: Focused on MRI and CT (간문맥 묘출을 위한 최적의 영상진단 장치에 관한 연구: MRI, CT 중심으로)

  • Goo, Eun-Hoe
    • Journal of the Korean Society of Radiology
    • /
    • v.13 no.2
    • /
    • pp.217-225
    • /
    • 2019
  • The purpose of this study was to quantitate signal to noise ratio and contrast to noise ratio of the portal vein using CT and 3.0T MRI and to investigate the optimal imaging device. Twenty patients who inspective CT and 3.0T MRI between February 2018 and April 2018 were randomly assigned to receive data from the picture archiving communication system. The SNR and CNR values were evaluated by measuring the mean and standard deviation of the region of interest of the four regions of the portal vein (the main portal vein, the right vein, the left vein, and the middle vein). The results showed that SNR was 9.180.72 in the right context, 9.410.84 in the left context, 9.540.59 in the middle context, 9.550.75 in the order context, and 22.292.03 in the right context and 25.893 in the 3.0T MRI. 19, median context: 24.392.87, and order Mac: 26.642.30 (p<0.05). CNR was 3.790.68 in the CT context, 3.740.65 in the left context, 3.710.39 in the middle context, 3.790.68 in the order context, 9.490.65 in the right context, and 11.0001.90 in the 3.0T MRI, Intermediate context: 12.701.75, order Mac: 10.010.98, 3.0T MRI was higher than CT (p<0.05). In conclusion, SNR and CNR values were higher in the 3.0T MRI than CT in the 4 portal regions. Therefore, 3.0T MRI using non-ionizing radiation was the most superior imaging equipment than CT.

Validation of Korean Diagnostic Scale of Multiple Intelligence (한국형 다중지능 진단도구의 타당화)

  • Moon, Yong-Lin;Yu, Gyeong-Jae
    • (The) Korean Journal of Educational Psychology
    • /
    • v.23 no.3
    • /
    • pp.645-663
    • /
    • 2009
  • The purpose of this study is to develop and verify a Korean Diagnostic Scale of Multiple Intelligence(MI), which will be an alternative test to avoid problems with former Shearer's MI test and to adopt H. Gardner's suggestions to develop MI assessment. The test is developed 5 types; kindergartner, elementary lower grader, elementary upper grader, middle schooler, high schooler test. A form of test is diversified with 3 types; multiple-choice items for accomplishment, true or false items for ability, and self-reported items with likert scale for interest and ability. According to H. Gardner's suggestions, we have tried to reanalyze key component of MI, analyze an overlapping or hierarchical relationship between intelligences, develop intelligences-fair items, diversify form of item. We have developed a final standardized test through a primary, secondary preliminary-test analysis, and sampled 5,585 students by age, gender, and regional groups. As a result of this sampling test, we can get a norm score and compare individuals with other's score relatively. To verify this test, we analyzed behavior observation, mean, standard deviation, a percentage of correct answers, reliability of each test type, correlation between intelligence scales, Kruskal-Wallis test of mean rank of career choice by intelligences. As a result of correlation analysis between sub-intelligence scales, we can conclude that this MI test is satisfied with intelligence independent assumption. Besides, as non-parametric statistics test(Kruskal-Wallis) of career choice by intelligences, we can identify that MI is related with domain of career choice. This test is not a linguistic and logical-mathematical biased test but a intelligences-fair test. It makes us compare individual's potential with a norm score. Besides, it could be useful as a means of educational prescription or counsel in comparison with ability, interest, and accomplishment of individual. But this test is limited to do factor or correlation analysis between types of sub-test, because items are minimized for a time-constraint and a heavy burden of test receiver. But if it could be tested with increased items by two sessions, further research could be expected to get over this constraints and do a further validation analysis.

The Optimization and Verification of an Analytical Method for Sodium Iron Chlorophyllin in Foods Using HPLC and LC/MS (식품 중 철클로로필린나트륨의 HPLC 및 LC/MS 최적 분석법과 타당성 검증)

  • Chong, Hee Sun;Park, Yeong Ju;Kim, Eun Gyeom;Park, Yea Lim;Kim, Jin Mi;Yamaguchi, Tokutaro;Lee, Chan;Suh, Hee-Jae
    • Journal of Food Hygiene and Safety
    • /
    • v.34 no.2
    • /
    • pp.148-157
    • /
    • 2019
  • An optimized analytical method for sodium iron chloriphyllin in foods was established and verified by using high performance liquid chromatography with attached diode array detection. An Inertsil ODS-2 column and methanol-water (80:20 containing 1% acetate) as a mobile phase were employed. The limit of detection and quantitation of sodium iron chloriphyllin were 0.1 and 0.3 mg/kg, respectively, and the linearity of calibration curve was excellent ($R^2=0.9999$). The accuracy and precision were 93.9~104.95% and 2.0~7.7% in both inter-day and intra-day tests. Recoveries for candy and salad dressing were ranged between 93 and 104% (relative standard deviation, (RSD) 0.3~4.3%), and between 83 and 115% (RSD 1.2~2.0%), respectively. Liquid chromatography mass spectrometry was used to verify the main components of sodium iron chlorophyllin which were Fe-isochlorin e4 and Fe-chlorin e4.

Literature Review and Analysis on Research Trends of Sociology in the Journal of Korean Gerontological Society (한국노년학의 사회학 분야 연구동향)

  • Kim, Ju-Hyun;Yeom, Jihye;Kim, Tae-il
    • 한국노년학
    • /
    • v.38 no.3
    • /
    • pp.745-766
    • /
    • 2018
  • The purpose of this study is to examine the research trends regarding the published articles in the Journal of Korean Gerongological Society within the past 10 years. This study is based on the article written by Won and Mo (2008). This article classified previously published studies into themes, methods, and application of theory. Out of the total of 187 articles published in the past 10 years, 11 articles were about social change and institution, 94 articles were about social issues, 12 articles were about social problems and deviation, 42 articles were about social culture, 14 papers were about gerontological theory and 13 papers were about residence/architecture. In the last 10 years, the most popular topic was around the various ways aging. New topic that emerged was the effect of IT and technology on the quality of life among the older adults. Other topics that gained interest were age discrimination and prejudice on aging. Trends in research methods showed increased use of qualitative methods. In the future, more research needs to be completed to theorize the results of quantitative research. Furthermore, the use of qualitative research methods needs to be increased in order to understand the lives of older adults in depth. Through more meta analysis, the results of past research articles should be synthesized to get a bigger picture of the Korean older adults.