• Title/Summary/Keyword: agreement statistics

Search Result 214, Processing Time 0.026 seconds

Evaluation of the Possibility of Daily Flow Data Generation from 8-Day Interval Measured Flow Data using SWAT-CUP (SWAT-CUP을 이용한 8일간격 유량측정자료의 일유량 확장 가능성 평가)

  • Jung, Jaewoon;Cho, Sohyun;Lim, Byungjin;Oh, Taeyoun;Ham, Sangin;Kim, Kapsoon
    • Journal of Korean Society on Water Environment
    • /
    • v.28 no.4
    • /
    • pp.595-600
    • /
    • 2012
  • This study is to assess the application of SWAT-CUP(Soil and Water Assessment Tool-Calibration Uncertainty Programs) and to extend daily flow data from 8-day interval flow data which has been measured by Korean Ministry of Environment(MOE). Model sensitivity analysis and calibration were performed with sequential uncertainty fitting(SUIF-2), which is one of the programs interfaced with SWAT, in the package SWAT-CUP. The most sensitive parameters were SOL_K.sol, CH_N2.rte, CN2.mgt, SOL_BD.sol, ALPHA_BF.gw, ALPHA_BNK.rte, SOL_AWC.sol, CH_K2.rte, SFTMP.bsn, GW_DELAY.gw. Following the sensitivity analysis, SWAT-CUP calibration was carried out using 8-day interval flow data from January 2008 to December 2010. The results were then assessed based on the visual agreement and simulated flow plots and the performance statistics generated $R^2$ and NSE which are 0.71 and 0.61 respectively. Results of these statistics indicated that there was a good agreement between the observed and simulated flow. To extend daily flow data from 8-day interval flow data, parameters, which were estimated by SWAT-CUP, re-entered for SWAT model. As a result, the observed flow data were found to reflect the trend of simulated flow data. From these results, it is thought that this method could be used to provide daily flow data using 8-day interval flow data.

Validity of Self-reported Stroke and Myocardial Infarction in Korea: The Health Examinees (HEXA) Study

  • Choe, Sunho;Lee, Joonki;Lee, Jeeyoo;Kang, Daehee;Lee, Jong-Koo;Shin, Aesun
    • Journal of Preventive Medicine and Public Health
    • /
    • v.52 no.6
    • /
    • pp.377-383
    • /
    • 2019
  • Objectives: Self-reported disease history is often used in epidemiological studies. In this study, we acquired the hospital records of subjects who self-reported stroke or myocardial infarction (MI) and evaluated the validity of the participants' self-reported disease history. We also determined the level of agreement between specialists and non-specialists. Methods: Among the participants in the Health Examinees study, 1488 subjects self-reported stroke or MI during 2012-2017, and medical records were acquired for the 429 subjects (28.8%) who agreed to share their medical information. Each record was independently assigned to 2 medical doctors for review. The records were classified as 'definite,' 'possible,' or 'not' stroke or MI. If the doctors did not agree, a third doctor made the final decision. The positive predictive value (PPV) of self-reporting was calculated with the doctors' review as the gold standard. Kappa statistics were used to compare the results between general doctors and neurologists or cardiologists. Results: Medical records from 208 patients with self-reported stroke and 221 patients with self-reported MI were reviewed. The PPV of self-reported disease history was 51.4% for stroke and 32.6% for MI. If cases classified as 'possible' were counted as positive diagnoses, the PPV was 59.1% for stroke and 33.5% for MI. Kappa statistics showed moderate levels of agreement between specialists and nonspecialists for both stroke and MI. Conclusions: The validity of self-reported disease was lower than expected, especially in those who reported having been diagnosed with MI. Proper consideration is needed when using these self-reported data in further studies.

Development and validation of a novel screening instrument to prioritize the orthodontic referral of developing malocclusion in children: The index for interceptive orthodontics referral

  • Saraswathy Devi Sinniah;Annapurny Venkiteswaran;Najiyatu Nazihah Zakaria
    • The korean journal of orthodontics
    • /
    • v.53 no.2
    • /
    • pp.116-124
    • /
    • 2023
  • Objective: The absence of a guideline to refer to developing malocclusions appropriately, may be a contributing factor to the inadequacy of timely interceptive orthodontics provision. This study aimed to develop and validate a new orthodontic grading and referral index to be used by dental frontliners to prioritize the orthodontic referral of developing malocclusion in children based on its severity. Methods: A cross-sectional study involving clinical assessment with 413 schoolchildren aged between 8.1 and 11.9 years was conducted in 2018. All the presenting malocclusion was listed and graded based on a few dental guidelines to produce the draft index. The validity and reliability of the draft index were tested using twenty study models. Face and content validation was carried out using the content validation index and Modified Kappa Statistics. Results: Fourteen dental and occlusal anomalies were identified as components of malocclusion and three grades of referral (monitor, standard, urgent) were included in the final index. The scale-level content validity index average value of 0.86 and 0.87 was obtained for content and face validation, respectively. There was moderate to excellent agreement in the Modified Kappa Statistics for both validations. Excellent inter- and intra-assessor agreement was obtained. The new index displayed valid and reliable scores. Conclusions: The Index for Interceptive Orthodontics Referral was developed and validated for the dental frontliners to identify and prioritize the developing malocclusion in children based on its severity and refer for orthodontic consultation to increase the possibility for interceptive orthodontics.

A Case Study on Effect of Statistics Class focusing on Statistical Argumentation (통계적 논증활동을 강조한 통계수업의 효과에 대한 사례연구)

  • Kang, Hyun-Young;Song, Eun-Young;Cho, Jin-Woo;Lee, Kyeong-Hwa
    • Journal of Educational Research in Mathematics
    • /
    • v.21 no.4
    • /
    • pp.399-422
    • /
    • 2011
  • There has been an agreement on the necessity for each citizen is to be educated, so called, to develop quantitative literacy or statistical literacy, dealing with real world data. For this reason, it is highly demanded to improve traditional statistics education. In particular, critical thought and statistical communication competency cultivation is becoming more crucial in statistics classes. In line with this reform movement in statistics education, we developed tasks facilitating statistical debate among students through inducing cognitive conflict. The tasks employed for this study resulted in playing crucial role to activate statistical debate. Including aforementioned feature about the tasks for this study, we obtained several positive results such as promoting critical thought and conceptual extension by designed teaching experiment focusing on statistical debate.

  • PDF

A Modified Length-Based Grading Method for Assessing Coronary Artery Calcium Severity on Non-Electrocardiogram-Gated Chest Computed Tomography: A Multiple-Observer Study

  • Suh Young Kim;Young Joo Suh;Na Young Kim;Suji Lee;Kyungsun Nam;Jeongyun Kim;Hwan Kim;Hyunji Lee;Kyunghwa Han;Hwan Seok Yong
    • Korean Journal of Radiology
    • /
    • v.24 no.4
    • /
    • pp.284-293
    • /
    • 2023
  • Objective: To validate a simplified ordinal scoring method, referred to as modified length-based grading, for assessing coronary artery calcium (CAC) severity on non-electrocardiogram (ECG)-gated chest computed tomography (CT). Materials and Methods: This retrospective study enrolled 120 patients (mean age ± standard deviation [SD], 63.1 ± 14.5 years; male, 64) who underwent both non-ECG-gated chest CT and ECG-gated cardiac CT between January 2011 and December 2021. Six radiologists independently assessed CAC severity on chest CT using two scoring methods (visual assessment and modified length-based grading) and categorized the results as none, mild, moderate, or severe. The CAC category on cardiac CT assessed using the Agatston score was used as the reference standard. Agreement among the six observers for CAC category classification was assessed using Fleiss kappa statistics. Agreement between CAC categories on chest CT obtained using either method and the Agatston score categories on cardiac CT was assessed using Cohen's kappa. The time taken to evaluate CAC grading was compared between the observers and two grading methods. Results: For differentiation of the four CAC categories, interobserver agreement was moderate for visual assessment (Fleiss kappa, 0.553 [95% confidence interval {CI}: 0.496-0.610]) and good for modified length-based grading (Fleiss kappa, 0.695 [95% CI: 0.636-0.754]). The modified length-based grading demonstrated better agreement with the reference standard categorization with cardiac CT than visual assessment (Cohen's kappa, 0.565 [95% CI: 0.511-0.619 for visual assessment vs. 0.695 [95% CI: 0.638-0.752] for modified length-based grading). The overall time for evaluating CAC grading was slightly shorter in visual assessment (mean ± SD, 41.8 ± 38.9 s) than in modified length-based grading (43.5 ± 33.2 s) (P < 0.001). Conclusion: The modified length-based grading worked well for evaluating CAC on non-ECG-gated chest CT with better interobserver agreement and agreement with cardiac CT than visual assessment.

Correlation of the Wall Skin-Friction and Streamwise Velocity Fluctuations in a Turbulent Boundary Layer(I) -Analysis of Long-Time Averaged Space-Time Correlation- (난류경계층에서 벽마찰력과 유동방향 속도성분과의 상관관계(I)-시간 평균된 공간-시간 상관관계의 분석-)

  • Yang, Jun-Mo;Yu, Jeong-Yeol;Choe, Hae-Cheon
    • Transactions of the Korean Society of Mechanical Engineers B
    • /
    • v.21 no.1
    • /
    • pp.140-152
    • /
    • 1997
  • A simultaneous measurement of the wall skin friction and near-wall streamwise velocity fluctuations is performed using hot film and hot wire anemometers to investigate the relation between them. Near-wall turbulence statistics measured with a hot-wire probe are in good agreement with previous results. Turbulence properties of the wall skin friction fluctuations measured with a hot film also show fairly good agreements with those measured by others except that rms level is lower in the present study. Long-time averaged space- time correlations show that the wall skin friction is highly correlated with a turbulence structure which is tilted from the wall in the streamwise direction. Tilting angles are obtained from the phase shifts between the wall skin-friction and streamwise velocity fluctuations. The convection velocity of the near-wall streamwise velocity obtained from the space-time correlation is in good agreement with that from the direct numerical simulation database.

Renewable energy deployment policy-instruments for Cameroon: Implications on energy security, climate change mitigation and sustainable development

  • Enow-Arrey, Frankline
    • Bulletin of the Korea Photovoltaic Society
    • /
    • v.6 no.1
    • /
    • pp.56-68
    • /
    • 2020
  • Cameroon is a lower middle-income country with a population of 25.87 million inhabitants distributed over a surface area of 475,442 ㎢. Cameroon has very rich potentials in renewable energy resources such as solar energy, wind energy, small hydropower, geothermal energy and biomass. However, renewable energy constitutes less than 0.1% of energy mix of the country. The energy generation mix of Cameroon is dominated by large hydropower and thermal power. Cameroon ratified the Paris Agreement in July 2016 with an ambitious 20% greenhouse gas (GHG) emission reduction. This study attempts to investigate some renewable energy deployment policy-instruments that could enable the country enhance renewable energy deployment, gain energy independence, fulfill Nationally Determined Contribution (NDC) and achieve Sustainable Development Goals. It begins with an analysis of the status of energy sector in Cameroon. It further highlights the importance of renewable energy in mitigating climate change by decarbonizing the energy mix of the country to fulfill NDC and SDGs. Moreover, this study proposes some renewable energy deployment policy-solutions to the government. Solar energy is the most feasible renewable energy source in Cameroon. Feed-in Tariffs (FiT), is the best renewable energy support policy for Cameroon. Finally, this study concludes with some recommendations such as the necessity of building an Energy Storage System as well a renewable energy information and statistics infrastructure.

Imputation method for missing data based on measure of property (특성도를 이용한 결측치 대체방법)

  • Kim, Hyungju;Kim, Dongjae
    • The Korean Journal of Applied Statistics
    • /
    • v.30 no.3
    • /
    • pp.463-473
    • /
    • 2017
  • How to handle missing data is a main issue in clinical trials. We impute missing data based on missing data that follows a mechanism according to the intention-to-treat rule. However, using the right imputation method for missing data is very important because this supposition is unclear. We suggest a new imputation method for missing data using agreement and maintenance introduced by Kang and Kim (1997). We give an example and adapt a Monte Carlo simulation to compare the performance between the established method and the suggested method.

Community Resident's Use of Elementary School Facilities (지역사회인의 초등학교시설 이용)

  • Min, Chang-Kee
    • Journal of the Korean Institute of Educational Facilities
    • /
    • v.5 no.3
    • /
    • pp.98-106
    • /
    • 1998
  • This paper is to find out a possibility that, adapting article 81 of regional finacing law, the community develops community facilities such as gymnagiums, swimming pools, and parking facilities in school site. The study requires an agreement about managements between the mayor and the superintendent of education. This paper also surveys community's needs with respect to use of school facilities before and after class, willingness to pay for the school use, and use of school facilities by private institutions. This paper adopts two experimental case studies to find a feasibility of community building construction in school sites. It also adopts dscriptive analysis of the statistics to find out the degree of willingness to use by community people. It is found, first, that regional finacing law permits community facilities' development in school sites and an agreement between the mayor and the superintendent of education about usage and profits should be made by the rate of construction fee and land cost. The second is that 65.8% of community people want to use school facilities such as gymnasium and school ground. And favorite series of physical exercise is swimming, baminton, tennis in order. The third is that 66.4% of community people have willingness to pay for the use of school facilities. The fourth is that school facilities such as class room, special class room, and computer room can be used by private institutions. 75% of community people agree to use school facilities by the private institutions. Favorite series on these are classes for reviewing the lessons, language classes, classes for playing musical instruments in order.

  • PDF

Study on Accuracy of DSOM Diagnosis about Uterus Myoma Patients (자궁근종 치료환자를 대상으로 한 DSOM 진단정확도에 대한 연구)

  • Um, Yun-Kyung;Kim, Jong-Won;Ji, Gyu-Yong;Lee, Yong-Tae;Kim, Gyu-Gon;Lee, In-Seon
    • Journal of Physiology & Pathology in Korean Medicine
    • /
    • v.20 no.3
    • /
    • pp.740-747
    • /
    • 2006
  • This study was undertaken to clinically inspect the accuracy of DSOM-diagnosis System of Oriental Medicine, which were used for the object diagnosis of oriental medicine in the dept. of oriental OB&GY, oriental medical hospital of Dong-Eui University- about uterus myoma patients. We analyzed the prescription and consequence of diagnosis about 16 patients -who had uterus myoma, were treated more than one month, were improved in myoma size, dysmenorrhea, menorrhagia- in the oriental medical hospital of Dong-Eui University from January to December 2004. The calculation consequence of disease mechanism was as follows. The stagnation of Ki(氣滯), liver(肝), heart.(心) was 10 patients 71.4%, some deficiency(虛證), wet syndrome(濕), cold syndrome(寒) was 9 patients 64.3%, blood stasis(血奈) was 8 patients 57.1%. The agreement of consequence about DSOM and diagnosis was 13 patients, 92.9%.