• Title/Summary/Keyword: representative statistics

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Quantitative Evaluation of Hepatic Steatosis Using Advanced Imaging Techniques: Focusing on New Quantitative Ultrasound Techniques

  • Junghoan Park;Jeong Min Lee;Gunwoo Lee;Sun Kyung Jeon;Ijin Joo
    • Korean Journal of Radiology
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    • v.23 no.1
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    • pp.13-29
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    • 2022
  • Nonalcoholic fatty liver disease, characterized by excessive accumulation of fat in the liver, is the most common chronic liver disease worldwide. The current standard for the detection of hepatic steatosis is liver biopsy; however, it is limited by invasiveness and sampling errors. Accordingly, MR spectroscopy and proton density fat fraction obtained with MRI have been accepted as non-invasive modalities for quantifying hepatic steatosis. Recently, various quantitative ultrasonography techniques have been developed and validated for the quantification of hepatic steatosis. These techniques measure various acoustic parameters, including attenuation coefficient, backscatter coefficient and speckle statistics, speed of sound, and shear wave elastography metrics. In this article, we introduce several representative quantitative ultrasonography techniques and their diagnostic value for the detection of hepatic steatosis.

Applications of the Sediment-Transport Path Model to the Tidal Flats of Garolim Bay, West Coast of Korea

  • Shin, Dong-Hyeok;Yi, Hi-Il;Han, Sang-Joon;Oh, Jae-Kyung;Won, Joong-Sun
    • International Union of Geodesy and Geophysics Korean Journal of Geophysical Research
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    • v.23 no.1
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    • pp.39-51
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    • 1995
  • Bidirectional transport trend using the sediment-transport path model was identified in the two areas, sand ridge area and tidal mudflat in Garolim Bay, which is located in the mid-western coast of Korean Peninsular. This model exhibits the two-dimensional view of clear sediment transport trend based on data of changes in sediment statistics such as mean, sorting, and skewness, Garolim Bay was selected to test for the sediment-transport path model developed by McLaren and Bowles [1985]. Line-S, a typical tidal mudflat and representative of the Garolim Bay tidal flats, is well tested by this model, showing a clear seasonal change and coarsening-trend seaward (case C). This indicates that strong ebb currents carried relatively coarser sediments seaward with respect to high energy regime. Seasonally, this energy regime slowly decreases toward the summer in contrast with an increase of energy regime of flood tides, carrying coarser sediments landward (case C) in the summer. However, the Line-D area does not show consistent transport trend with respect to time-series. Separated and scattered events show fining trend landward (case B) in the sand ridge itself. The finining-trend (case B) either seaward and landward is not chiefly important in both the entire Line-D area and sand ridge itself. Also, the coarsening-Trend (case C) landward is not significant in the sand ridge itself. Consequently, in reality, the selection of suitable and representative locations are very important to fit with this model.

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Who has experienced better or worse health conditions since the outbreak of COVID-19?: results from a representative cross-sectional survey in Seoul

  • Eunbin Jo;Hyelim Yoo;Kirang Kim;Sunup Kim;Chul-Kyoo Kim;Haeyoen Lee;Jinsook Jeong;Sohyun Park
    • Nutrition Research and Practice
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    • v.17 no.1
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    • pp.103-121
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    • 2023
  • BACKGROUND/OBJECTIVES: The coronavirus disease 2019 (COVID-19) pandemic has affected the entire world population in many ways. This study aimed to analyze the patterns of changes in eating, food purchasing and preparation, physical activity, and subjective health after COVID-19 outbreak by various sociodemographic factors and to understand the factors associated with changes in subjective health. SUBJECTS/METHODS: A cross-sectional survey using a representative sample from Seoul was used for the analysis. The data collection was conducted from September to October 2020. A total of 3,833 citizens aged more than 18 years old participated in the Seoul Food Survey. Descriptive statistics and generalized ordinal logistic regression models were used to understand the changes in health behaviors, health indicators, and subjective general health by various socioeconomic status. RESULTS: It was shown that the changes in household income, food expenditure, food consumption and physical activities differed significantly by age, education, occupation, income, weight, and food security status. Low-income and food-insecure households were affected more severely by the pandemic. Older age, household food insecurity, income reduction, increased home cooking and frequency of having instant foods, decreased physical activity and weight gain were significant factors explaining worse perceived health during the COVID-19 pandemic. CONCLUSIONS: The results suggest that focusing on older populations and low-income families with food insecurity should be prioritized during infectious disease outbreaks. In addition, the role of physical activities and instant food consumption in explaining perceived health should be investigated further in this prolonged battle with the pandemic situation.

Development of household production satellite and application based on the establishment of concept and standardized measurement for household production (가정생산 위성계정의 개발 및 적용: 새로운 개념 정립과 표준화된 측정방법을 중심으로)

  • Park, Hyun-Jung;Hong, Hyunjeong;Huh, Kyungok
    • Journal of Family Resource Management and Policy Review
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    • v.17 no.2
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    • pp.55-74
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    • 2013
  • This research developed standardized satellite accounts for household production to measure the entire production in Korea using representative Korean data. This study utilized standardized methods for measuring the expenditure and consumption of expendable supplies as an element of intermediate goods in household production. The results of this research can be summarized as follows. First, the total value of household production in Korea in 2009 turned was 268 trillion won, which would be 10.16% of the GDP, based on using the method of replacement by specialty for estimating the value of housework, while it was 356 trillion won, which would be 13.5% of the GDP (2,636 trillion won), based on the method of opportunity cost. Second, the economic value of labor invested in household production was 220 trillion won when using the data from 12 main corresponding wages in the market, while it was 203 trillion won when using the method of total replacement, which used the wages of housekeepers, and 290 trillion won when using the method of opportunity cost in measuring the value of housework labor. Third, in estimating the proportion by section in terms of the total value of household production, the portion of labor in household production was measured from 76% to 82%, depending on the methods used, which is the most significant section. These results indicate that housework has the characteristics of labor-centered work. On the other hand, the value of expenditure on and consumption of expendable supplies, as one element of intermediate goods, is 63 trillion won, which is 17.7% (using the method of opportunity cost in measuring the labor of housework) of household production. Also, the value of capital goods, as the other element of intermediate goods is 2.3 trillion won, which is 0.9% (using the method of opportunity cost) of household production. In conclusion, as an element of household production, housework labor was higher in household production than expenditures on expendables, especially for cooking, cleaning, and caring for children. In the future, people should be cautious about estimating that the amount of household work could be reduced, as women's labor in the market and the household work produced by the market will increase.

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Bayesian structural equation modeling for analysis of climate effect on whole crop barley yield (청보리 생산량의 기후요인 분석을 위한 베이지안 구조방정식 모형)

  • Kim, Moonju;Jeon, Minhee;Sung, Kyung-Il;Kim, Young-Ju
    • The Korean Journal of Applied Statistics
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    • v.29 no.2
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    • pp.331-344
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    • 2016
  • Whole Crop Barley (WCB) is a representative self-sufficient winter annual forage crop, along with Italian Ryegrass (IRG), in Korea. In this study, we examined the path relationship between WCB yield and climate factors such as temperature, precipitation, and sunshine duration using a structural equation model. A Bayesian approach was considered to overcome the limitations of the small WCB sample size. As prior distribution of parameters in Bayesian method, standard normal distribution, the posterior result of structural equation model for WCB, and the posterior result of structural equation model for IRG (which is the most popular winter crop) were used. Also, Heywood case correction in prior distribution was considered to obtain the posterior distribution of parameters; in addition, the best prior to fit the characteristics of winter crops was identified. In our analysis, we found that the best prior was set by using the results of a structural equation model to IRG with Heywood case correction. This result can provide an alternative for research on forage crops that have hard to collect sample data.

Topic change monitoring study based on Blue House national petition using a control chart (관리도를 활용한 국민청원 토픽 모니터링 연구)

  • Lee, Heeyeon;Choi, Jieun;Lee, Sungim;Son, Won
    • The Korean Journal of Applied Statistics
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    • v.34 no.5
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    • pp.795-806
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    • 2021
  • Recently, as text data through online channels have become vast, there is a growing interest in research that summarizes and analyzes them. One of the fundamental analyses of text data is to extract potential topics. Although the researcher may read all the data and summarize the contents one by one, it is not easy to deal with large amounts of data. Blei and Lafferty (2007) and Blei et al. (2003) proposed topic modeling methods for extracting topics using a statistical model. Since the text data is generally collected over time, it is worthwhile to monitor the topic's changes. In this study, we propose a topic index based on the results of the topic model. In addition, a control chart, a representative tool for statistical process management, is applied to monitor the topic index over time. As a practical example, we use text data collected from Blue House National Petition boards between March 5, 2018, and March 5, 2020.

Spatio-temporal analysis with risk factors for five major violent crimes (위험요인이 포함된 시공간 모형을 이용한 5대 강력범죄 분석)

  • Jeon, Young Eun;Kang, Suk-Bok;Seo, Jung-In
    • The Korean Journal of Applied Statistics
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    • v.35 no.5
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    • pp.619-629
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    • 2022
  • The five major violent crimes including murder, robbery, rape·forced indecent act, theft, and violence are representative crimes that threaten the safety of members of society and occur frequently in real life. These crimes have negative effects such as lowering the quality of citizens' life. In the case of Seoul, the capital of Korea, the risk for the five major violent crimes is increasing because the population density of Seoul is increasing as a large number of people in the provinces move to Seoul. In this study, to reduce this risk, the relative risk for the occurrence of the five major violent crimes in Seoul is modeled using three spatio-temporal models. In addition, various risk factors are included to identify factors that significantly affect the relative risk of the five major violent crimes. The best model is selected in terms of the deviance information criterion, and the analysis results including various visualizations for the best model are provided. This study will help to establish efficient strategies to sustain people's safe everyday living by analyzing important risk factors affecting the risk of the five major violent crimes and the relative risk of each region.

Trends in Percutaneous Coronary Intervention and Coronary Artery Bypass Surgery in Korea

  • Lee, Heeyoung;Lee, Kun Sei;Sim, Sung Bo;Jeong, Hyo Seon;Ahn, Hye Mi;Chee, Hyun Keun
    • Journal of Chest Surgery
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    • v.49 no.sup1
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    • pp.60-67
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    • 2016
  • Background: Coronary angioplasty has been replacing coronary artery bypass grafting (CABG) because of the relative advantage in terms of recovery time and noninvasiveness of the procedure. Compared to other Organization for Economic Cooperation and Development (OECD) countries, Korea has experienced a rapid increase in coronary angioplasty volumes. Methods: We analyzed changes in procedure volumes of CABG and of percutaneous coronary intervention (PCI) from three sources: the OECD Health Data, the National Health Insurance Service (NHIS) surgery statistics, and the National Health Insurance claims data. Results: We found the ratio of procedure volume of PCI to that of CABG per 100,000 population was 19.12 in 2014, which was more than triple the OECD average of 5.92 for the same year. According to data from NHIS statistics, this ratio was an increase from 11.4 to 19.3 between 2006 and 2013. Conclusion: We found that Korea has a higher ratio of total procedure volumes of PCI with respect to CABG and also a more rapid increase of volumes of PCI than other countries. Prospective studies are required to determine whether this increase in absolute volumes of PCI is a natural response to a real medical need or representative of medical overuse.

Nutritional Quality of Korean Adults' Consumption of Lunch Prepared at Home, Commercial Places, and Institutions: Analysis of the Data from the 2001 National Health and Nutrition Survey (한국 성인의 점심식사에서 가정식, 상업적 외식 및 급식의 영양평가: 2001 국민건강.영양조사 자료의 분석)

  • Chung, Sang-Jin;Kang, Seung-Ho;Song, Su-Min;Ryu, Si-Hyun;Yoon, Ji-Hyun
    • Journal of Nutrition and Health
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    • v.39 no.8
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    • pp.841-849
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    • 2006
  • This study compared the nutritional quality of Korean adults's consumption of lunch prepared at home, commercial places, and institutions. The one day food intake data collected via 24-hour recall in the 2001 National Health and Nutrition Survey were analyzed. Individuals with 19-64 years of age were selected (n = 5,756). Sampling weights in the Survey were used to generate nationally representative estimates. Lunch was categorized into three groups according to the place where the lunch was prepared. home, commercial places, and institutions such as schools and work places. Comparison among the three groups was made for 19-39 years old men (n = 1,387) and women (n =1,572) and 40-64 years old men (n = 1,364) and women (1,433), respectively. The lunch prepared away from home contained more calories. The lunch prepared commercially was higher in calories percentages from fat than that prepared either at home or at institutions. Across the age and gender groups, lunch prepared at home contribute a high level of sodium intake. Among individuals with 40-64 years of age, but not those with 19-39 years of age, lunch prepared commercially was as sodium dense as that prepared at home. Among individuals with 19-39 years of age, the sodium density of lunch prepared commercially was about the same as that prepared at institutional food service of which the menus were planned by dieticians. Such differences in nutritional quality among meals prepared at home, commercial places, and institutions should be considered and applied for the content development of nutrition education and policy.

Cancer Risk Factors in Korean News Media: a Content Analysis

  • Kye, Su Yeon;Kwon, Jeong Hyun;Kim, Yong-Chan;Shim, Minsun;Kim, Jee Hyun;Cho, Hyunsoon;Jung, Kyu Won;Park, Keeho
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.2
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    • pp.731-736
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    • 2015
  • Background: Little is known about the news coverage of cancer risk factors in Korea. This study aimed to examine how the news media encompasses a wide array of content regarding cancer risk factors and related cancer sites, and investigate whether news coverage of cancer risk factors is congruent with the actual prevalence of the disease. Materials and Methods: A content analysis was conducted on 1,138 news stories covered during a 5-year period between 2008 and 2012. The news stories were selected from nationally representative media in Korea. Information was collected about cancer risk factors and cancer sites. Results: Of various cancer risk factors, occupational and environmental exposures appeared most frequently in the news. Breast cancer was mentioned the most in relation to cancer sites. Breast, cervical, prostate, and skin cancer were overrepresented in the media in comparison to incidence and mortality cases, whereas lung, thyroid, liver, and stomach cancer were underrepresented. Conclusions: To our knowledge, this research is the first investigation dealing with news coverage about cancer risk factors in Korea. The study findings show occupational and environmental exposures are emphasized more than personal lifestyle factors; further, more prevalent cancers in developed countries have greater media coverage, not reflecting the realities of the disease. The findings may help health journalists and other health storytellers to develop effective ways to communicate cancer risk factors.