• 제목/요약/키워드: Time trend analysis

검색결과 1,585건 처리시간 0.027초

암환자의 진단-치료 소요기간에 따른 생존분석과 지역사회별 격차 및 시계열적 추이 (The Impact of Time-to-Treatment for Outcome in Cancer Patients, and Its Differences by Region and Time Trend)

  • 김우림;한규태
    • 보건행정학회지
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    • 제31권1호
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    • pp.91-99
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    • 2021
  • Background: The Korean government introduced National Cancer Control Program and strengthening national health insurance coverage for cancer patients. Although many positive effects have been observed, there are also many concerns about cancer management such as patient concentration or time-to-treatment. Thus, we investigated the association between the time-to-treatment and survival of cancer patients, and compared regional differences by time trend. Methods: The data used in this study were national health insurance claims data that included patients diagnosed with lung cancer and received surgical treatment between 2005 and 2015. We conducted survival analysis with Cox proportional hazard model for the association between time-to-treatment and survival in lung cancer. Additionally, we compared the regional differences for time-to-treatment by time trend. Results: A total of 842 lung cancer patients were included, and 52.3% of lung cancer patients received surgical treatment within 30 days. Patients who received surgical treatment after 31 days had higher 5-year or 1-year mortality compared to treatment within 30 days (5-year: hazard ratio [HR], 1.566; 1-year: HR, 1.555; p<0.05). There were some regional differences for time-to-treatment, but it was generally reduced after 2010. Conclusion: Delayed surgical treatment after diagnosis can negatively affect patient outcomes in cancer treatment. To improve cancer control strategies, there are needed to analyze the healthcare delivery system for cancer care considering the severity and types of cancer.

일강우자료를 이용한 강우사상의 변동 특성 분석 (Characteristic Change Analysis of Rainfall Events using Daily Rainfall Data)

  • 오태석;문영일
    • 한국수자원학회논문집
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    • 제42권11호
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    • pp.933-951
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    • 2009
  • 지구온난화에 따른 기후변화가 우리나라의 물순환 과정에 영향을 미칠 수 있다. 강우는 여러 기상인자들과 복잡한 영향을 주고 받으며 발생한다. 따라서 강우는 물순환 과정에서 기후변화에 따른 영향을 크게 받는 인자 중의 하나이다. 본 연구에서는 강우특성을 나타낼 수 있는 여러 시계열 자료를 구축하였다. 또한 강우의 발생 시계열을 연별, 계절별 및 월별로 구성하여 분석하였다. 분석 방법은 시계열 자료의 평균과 표준편차의 변동성 분석과 경향성 분석을 수행하였다. 또한, 최근 10년 동안에 강우특성의 변화에 대한 상대오차를 계산하여 과거 자료들과 비교하였다. 분석 결과에서 강우자료의 고유 특성인 무작위성에 의하여 뚜렷한 통계적 결과는 나타나지 않았다. 그러나 일반적으로 최근 10년간 강우량은 증가하였으며, 강우일수는 감소하는 추세를 보였다. 또한, 계절별과 월별에 따른 강우특성의 변화가 다르게 나타나고 있음을 확인할 수 있다.

Comparative analysis of the wind characteristics of three landfall typhoons based on stationary and nonstationary wind models

  • Quan, Yong;Fu, Guo Qiang;Huang, Zi Feng;Gu, Ming
    • Wind and Structures
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    • 제31권3호
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    • pp.269-285
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    • 2020
  • The statistical characteristics of typhoon wind speed records tend to have a considerable time-varying trend; thus, the stationary wind model may not be appropriate to estimate the wind characteristics of typhoon events. Several nonstationary wind speed models have been proposed by pioneers to characterize wind characteristics more accurately, but comparative studies on the applicability of the different wind models are still lacking. In this study, three landfall typhoons, Ampil, Jongdari, and Rumbia, recorded by ultrasonic anemometers atop the Shanghai World Financial Center (SWFC), are used for the comparative analysis of stationary and nonstationary wind characteristics. The time-varying mean is extracted with the discrete wavelet transform (DWT) method, and the time-varying standard deviation is calculated by the autoregressive moving average generalized autoregressive conditional heteroscedasticity (ARMA-GARCH) model. After extracting the time-varying trend, the longitudinal wind characteristics, e.g., the probability distribution, power spectral density (PSD), turbulence integral scale, turbulence intensity, gust factor, and peak factor, are comparatively analyzed based on the stationary wind speed model, time-varying mean wind speed model and time-varying standard deviation wind speed model. The comparative analysis of the different wind models emphasizes the significance of the nonstationary considerations in typhoon events. The time-varying standard deviation model can better identify the similarities among the different typhoons and appropriately describe the nonstationary wind characteristics of the typhoons.

인공지능발달 토픽 프레임 연구 -계열화(seriation)와 통합화(skeumorph)의 사회구성주의 중심으로- (A Study on AI Evolution Trend based on Topic Frame Modeling)

  • 권상희;차현주
    • 한국콘텐츠학회논문지
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    • 제20권7호
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    • pp.66-85
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    • 2020
  • 본 연구의 목적은 AI 기술 특허(전체)와 주요 신문에 나타난 AI 보도 프레임을 바탕으로 AI 발달과정 추세를 예측하고 이를 기술·설명하는 것이다. 이를 위해 지난 9년간 출원된 한국과 미국 기술특허 요약문과 국내 주요 신문의 AI(Artificial Intelligence) 뉴스 텍스트를 분석하였다. 본 연구는 빅데이터를 활용한 토픽모델링과 시계열회귀분석이 사용되었으며, 추가로 네트워크 의제 상관분석과 회귀분석 기법이 사용되었다. 본 연구결과는 다음과 같다. 첫째, Topic 모델링 분석결과, AI 기술특허 요약문에서는 인공지능, 알고리즘 5G(Hot AI 기술) 등의 순으로 확인되었으며, AI 뉴스보도에서는 산업 적용, 데이터 활용과 시장 적용 등의 순으로 확인되어 AI의 사회문화 보도 경향을 나타냈다. 둘째, 시계열회귀분석결과, 상승추세 토픽으로는 사회문화적으로 AI 일상적·문화적 이용과 산업적용 시작이 도출되었다. 하락추세토픽으로는 시스템, 하드웨어 기술 중심으로 나타났다. 셋째, 상관관계와 회귀관계를 활용한 QAP 분석 결과, AI 기술특허와 뉴스 보도 프레임 간의 상관관계는 높은 것으로 나타났다. 이를 통해 AI 발달에서 AI 기술특허와 뉴스 보도 프레임이 미디어 담론의 결정요인에 의해 사회적으로 구성되는 것을 알 수 있었다.

Factor analysis of the trend of stream quality in Nakdong River

  • Kim, Kyong-Mu;Lee, In-Rak;Kim, Jong-Tae
    • Journal of the Korean Data and Information Science Society
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    • 제19권4호
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    • pp.1201-1210
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    • 2008
  • The goal of this paper is to investigate the trend of stream quality and the quality of water in Nakdong river by the method of factor analysis. It used the fourteen different monthly time series data such as pH, BOD, COD, SS, TN and etc. of the thirty four of Nakdong River measurement points from Jan. 1998 to Dec. 2006. The result of factor analysis is that the factor 1 results from organic water pollution is occupied 29.288% such as BOD, COD, TN and EC, and the factor 2 explained from sewage and a seasonal variation is occupied 16.467% such as SS.

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Korea's STEM Research Analysis Based on Publications in the Web of Science, 1968-2012

  • Kim, Byungkyu;So, Minho;Choi, Seon-Heui
    • Journal of Information Science Theory and Practice
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    • 제2권1호
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    • pp.35-47
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    • 2014
  • Korean researchers' scientific outputs are increasing rapidly with the growth of both Korea's economy and industry size. This is the time to analyze the scientific output (STEM area) of Korea over the last 40 years. For this analysis, this study used the SCIE database of Web of Science (WoS), which is a representative global Citation Index Service. The objects of analysis are every Korean document published in the SCIE journal, and the research scopes are (1) analysis of citation and subject categories and (2) analysis of co-authorship. Through this study, characteristics such as cited trend and research trend by subject, and the status of collaboration between Korea and other countries including the 50 states of the USA were revealed.

Leukemia in Iran: Epidemiology and Morphology Trends

  • Koohi, Fatemeh;salehiniya, Hamid;Shamlou, Reza;Eslami, Soheyla;Ghojogh, Ziyaeddin Mahery;Kor, Yones;Rafiemanesh, Hosein
    • Asian Pacific Journal of Cancer Prevention
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    • 제16권17호
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    • pp.7759-7763
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    • 2015
  • Background: Leukemia accounts for 8% of total cancer cases and involves all age groups with different prevalence and incidence rates in Iran and the entire world and causes a significant death toll and heavy expenses for diagnosis and treatment processes. This study was done to evaluate epidemiology and morphology of blood cancer during 2003-2008. Materials and Methods: This cross-sectional study was carried out based on re-analysis of the Cancer Registry Center report of the Health Deputy in Iran during a 6-year period (2003 - 2008). Statistical analysis for incidence time trends and morphology change percentage was performed with joinpoint regression analysis using the software Joinpoint Regression Program. Results: During the studied years a total of 18,353 hematopoietic and reticuloendothelial system cancers were recorded. Chi square test showed significant difference between sex and morphological types of blood cancer (P-value<0.001). Joinpoint analysis showed a significant increasing trend for the adjusted standard incidence rate (ASIR) for both sexes (P-value<0.05). Annual percent changes (APC) for women and men were 18.7 and 19.9, respectively. The most common morphological blood cancers were ALL, ALM, MM and CLL which accounted for 60% of total hematopoietic system cancers. Joinpoint analyze showed a significant decreasing trend for ALM in both sexes (P-value<0.05). Conclusions: Hematopoietic system cancers in Iran demonstrate an increasing trend for incidence rate and decreasing trend for ALL, ALM and CLL morphology.

구조적 시계열 모형을 이용한 기온 자료에 대한 기후변화 추세 분석 (Trends in the Climate Change of Surface Temperature using Structural Time Series Model)

  • 이정형;손건태
    • 대기
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    • 제18권3호
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    • pp.199-206
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    • 2008
  • This study employs a structural time series method in order to model and estimate stochastic trend of surface temperatures of the globe, Northern Hemisphere, and Northeast Asia ($20^{\circ}N{\sim}60^{\circ}N$, $100^{\circ}E{\sim}150^{\circ}E$). For this study the reanalysis data CRUTEM3 (CRU/Hadley Centre gridded land-surface air temperature Version 3) is used. The results show that in these three regions range from $0.268^{\circ}C$ to $0.336^{\circ}C$ in 1997, whereas these vary from $0.423^{\circ}C$ to $0.583^{\circ}C$ in 2007. The annual mean temperature over Northeast Asia has increased by $0.031^{\circ}C$ in 2007 compared to 1997. The climate change in surface temperatures over Northeast Asia is slightly higher than that over the Northern Hemisphere.

The Prevalence of Cardiovascular Disease Risk Factors and the Framingham Risk Score in Patients Undergoing Percutaneous Intervention Over the Last 17 Years by Gender: Time-trend Analysis From the Mayo Clinic PCI Registry

  • Lee, Moo-Sik;Flammer, Andreas J.;Kim, Hyun-Soo;Hong, Jee-Young;Li, Jing;Lennon, Ryan J.;Lerman, Amir
    • Journal of Preventive Medicine and Public Health
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    • 제47권4호
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    • pp.216-229
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    • 2014
  • Objectives: This study aims to investigate trends of cardiovascular disease (CVD) risk factor profiles over 17 years in percutaneous coronary intervention (PCI) patients at the Mayo Clinic. Methods: We performed a time-trend analysis within the Mayo Clinic PCI Registry from 1994 to 2010. Results were the incidence and prevalence of CVD risk factors as estimate by the Framingham risk score. Results: Between 1994 and 2010, 25 519 patients underwent a PCI. During the time assessed, the mean age at PCI became older, but the gender distribution did not change. A significant trend towards higher body mass index and more prevalent hypercholesterolemia, hypertension, and diabetes was found over time. The prevalence of current smokers remained unchanged. The prevalence of ever-smokers decreased among males, but increased among females. However, overall CVD risk according to the Framingham risk score (FRS) and 10-year CVD risk significantly decreased. The use of most of medications elevated from 1994 to 2010, except for ${\beta}$-blockers and angiotensin converting enzyme inhibitors decreased after 2007 and 2006 in both baseline and discharge, respectively. Conclusions: Most of the major risk factors improved and the FRS and 10-year CVD risk declined in this population of PCI patients. However, obesity, history of hypercholesterolemia, hypertension, diabetes, and medication use increased substantially. Improvements to blood pressure and lipid profile management because of medication use may have influenced the positive trends.

2000년 이후 패션의 주요 트렌드와 트렌드 이미지 (Trend Image and Major Trend of Fashion Since 2000)

  • 유현정
    • 한국의상디자인학회지
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    • 제12권3호
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    • pp.73-82
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    • 2010
  • The purpose of this study is to help understanding of fashion trend since 2000 years, to play a guideline's role in the development on fashion designs study. The methods of this study are the study of academic literatures as well as practical study through expert investigation and analysis of case studies about actual works. Fashion trends since 2000 years are summarized classic, sporty, elegance, ethnic, natural, romantic, vintage, futurism by expert investigation and analysis of case studies about actual works. Image of fashion trends are abstracted that Classic image is harmony, moderation, accuracy, completeness, neatness, manish from keep an archetype to eliminate additional things, Sporty image is daily, active, enjoyment by the pursuit of a movement and freedom, Elegance image is feminine, grace from the tender moderated and feminity, Ethnic image is folkway, handicraft, vernacular to keep national character, local folkways and traditional ways. Natural image is nature, peaceful, purity, pastoral to the exclusion of artificiality and revert to natural, Romantic image is sensibility, fantastic, ornament, splendid from facing ideal world getting out of the reality, Vintage image is cozy, old, disorder, faden, freedom by expressing the flow of time and the mature beauty, Futurism image is future, experimental, avant-garde, man-made from positive perspective on future.

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