• 제목/요약/키워드: target prevalence

검색결과 109건 처리시간 0.027초

표적 출현확률에 따른 시각탐색 정보처리 특성 (Characterizing Information Processing in Visual Search According to Probability of Target Prevalence)

  • 박형범;손한결;현주석
    • 인지과학
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    • 제26권3호
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    • pp.357-375
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    • 2015
  • 일상생활에서의 시각탐색의 대상이 되는 표적 사물의 출현 가능성 즉 출현 확률은 매우 낮은 경우부터 높은 경우까지 다양하다. 그럼에도 불구하고, 실험실 상황의 시각 탐색 연구에서 표적의 출현 확률은 대개 50%의 확률로 고정되는 경우가 대부분이다. 본 연구에서는 서로 다른 표적 출현확률의 영향 하에 시각탐색 과정에서의 정보처리 특성을 조사하였다. 지각적으로 단순한 도형자극으로 구성된 시각탐색과제가 실시되었으며, 탐색 표적이 제시되는 빈도를 저빈도(20%)와 중립빈도(50%), 또는 고빈도(80%)로 달리함으로써 표적 출현확률이 탐색 정보처리 책략에 미치는 영향을 탐색 정확도, 신호탐지 측정치 그리고 반응시간 차원에서 조사하였다. 실험 결과, 표적이 드물게 출현할수록 실수율이 증가하고 헛경보율이 감소했으며 반대로 고빈도 표적탐색에서는 역전된 패턴이 관찰되었다. 신호탐지 분석 결과, 이러한 결과는 민감도가 아닌 탐색 반응기준의 이동에 의한 것으로 확인되었다. 또한 반응시간 차원에서, 표적 있음 시행에서의 적중 반응은 출현확률과 관계없이 일정했던 반면 표적 없음 시행에 대한 정확한 기각 반응은 출현확률에 비례해 지연된 것이 관찰되었다. 이러한 결과는 표적이 빈번하게 출현할수록 표적 없음 상황에서 탐색을 종료하기 위한 탐색 역치 기준이 보수적이었음을 의미한다. 본 연구의 결과는 표적 출현확률 효과가 단순히 반응편향에 따른 속도-정확도 교환이 아닌 의사결정 기준의 변화에 기초한 상이한 탐색 정보처리 과정의 산물임을 시사한다.

변화출현확률이 시각단기기억 기반 변화탐지 수행에 미치는 영향 (The Influence of Change Prevalence on Visual Short-Term Memory-Based Change Detection Performance)

  • 손한결;현주석
    • 인지과학
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    • 제32권3호
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    • pp.117-139
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    • 2021
  • 짧은 시차를 두고 출현하는 기억과 검사배열 사이에 차이 항목의 유무를 찾아내는 변화탐지 원리는 검사배열 출현 시 기억항목들과 견주어 차이가 있는 한 항목을 탐색한다는 점에서 시각탐색 원리와 닮아있다. 본 연구는 두 과제 사이의 이러한 유사성을 배경으로, 시각단기기억 기반 변화탐지 과제에서 변화의 출현 가능성 증감이 변화탐지 반응의사결정에 미치는 영향 즉 변화출현확률 효과의 양상을 조사했다. 이를 위해 네 개의 색상 사각형에 뒤이어 출현한 또 다른 네 개의 색상 사각형 사이의 색상들을 비교해 색상 변화 항목의 유무를 판단하는 단순세부특징 변화탐지 과제를 실시했다. 변화 항목의 출현 가능성은 전체 시행 대비 20, 50 및 80% 확률로 처치되었으며 그에 따른 변화탐지 수행 오류와 탐지민감도 및 반응시간을 분석했다. 그 결과 변화 항목의 출현 가능성이 증가할수록 오경보는 증가하고 실수 반응은 감소했으며 정기각 반응시간 또한 지연된 것이 관찰되었다. 이 변화출현확률 효과는 시각탐색 과제에서 표적의 출현 가능성 증감에 따라 관찰되는 표적출현확률 효과와 매우 유사했으며 이는 두 효과를 초래하는 배경 원리가 서로 닮아있을 가능성을 시사한다.

Prevalence and Risk Factors for Opisthorchis viverrini Infections in Upper Northeast Thailand

  • Thaewnongiew, Kesorn;Singthong, Seri;Kutchamart, Saowalux;Tangsawad, Sasithorn;Promthet, Supannee;Sailugkum, Supan;Wongba, Narong
    • Asian Pacific Journal of Cancer Prevention
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    • 제15권16호
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    • pp.6609-6612
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    • 2014
  • Opisthorchis viverrini is an ongoing public health problem in Northeast Thailand. Despite continuous efforts for decades by healthcare organizations to overcome this problem, infection rates remain high. To enable related personnel to identify and address the various issues effectively, a cross-sectional study was performed to investigate prevalence and risk factors for opisthorchiasis. The target group was 3,916 Thai residents of Northeast Thailand who were 15 or over. Participants were recruited using the 30 clusters sampling technique. The data were gathered through questionnaires, focus group discussions, in-depth interviews, and stool examinations for parasite eggs (using the Modified Kato Katz method). The data were analyzed using descriptive and inference statistics; in order to ascertain the risk factors and test them using the odds ratio and multiple logistic regressions. The prevalence of opisthorchiasis was 22.7% (95%CI: 0.26 to 0.24). The province with the highest prevalence was Nakhorn Phanom (40.9%; female to male ratio =1:1.2). The age group with the highest prevalence was 40-49 year olds. All age groups had a prevalence >20%. Four of seven provinces had a prevalence >20%. The factors related to opisthorchiasis were (a) sex, (b) age (especially > 50), (c) proximity and duration living near a water body, and (d) eating raw and/or fermented fish. In order to reduce the prevalence of opisthorchiasis, the focus in populations living in upper Northeast Thailand should be changing their eating behaviors as appropriate to their tradition and context.

Prevalence and Clinical Significance of Mammalian Target of Rapamycin Phosphorylation (p-mTOR) and Vascular Endothelial Growth Factor (VEGF) in Clear Cell Carcinoma of the Ovary

  • Khemapech, Nipon;Pitchaiprasert, Sunaree;Triratanachat, Surang
    • Asian Pacific Journal of Cancer Prevention
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    • 제13권12호
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    • pp.6357-6362
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    • 2012
  • Background: To determine the prevalence of mammalian target of rapamycin phosphorylation (p-mTOR) and vascular endothelial growth factor (VEGF) and any correlation with clinical characteristics and prognosis in ovarian clear cell carcinoma patients. Materials and Method: Seventy four paraffin-embedded specimens of such carcinomas frompatients who underwent surgery, received adjuvant chemotherapy and were followed up at King Chulalongkorn Memorial Hospital during January 2002 to December 2008 were stained with rabbit monoclonal IgG p-mTOR and rabbit polyclonal IgG VEGF using immunohistochemical methods. Medical records were reviewed and clinical variables were analysed. Results: The prevalence of positive p-mTOR in ovarian clear cell carcinoma was 87.9% and significantly higher in advance-stage than early-stage patients (100% versus 83.6%, P<0.05). Two-year disease free survival and 2-year overall survival in patients with positive p-mTOR expression were 60% and 69.2% with no differences from patients with negative p-mTOR expression (p>0.05). The prevalence of VEGF expression was 63.5% and significantly higher in chemo-sensitive than chemo-resistant patients (70.7% versus 37.5%, P<0.05). Two-year disease free survival and 2-year overall survival in patients with VEGF expression were 72.3% and 83% respectively which were significantly different from patients with negative VEGF expression (p<0.05). Conclusions: p-mTOR expression in ovarian clear cell carcinoma was significantly correlated with the stage of disease. VEGF expression was significantly correlated with chemosensitivity, and survival. Further studies of related targeted therapy might be promising.

한국 임금근로자의 작업환경과 흡연율 간의 관계에 대한 연구 (Association between Working Conditions and Smoking Status among Korean Employees)

  • 김지윤
    • 한국직업건강간호학회지
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    • 제24권3호
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    • pp.204-213
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    • 2015
  • Purpose: This study investigated the relationship between working conditions and smoking among Korean employees using nationally representative data. Methods: We analyzed data from the Third Korean Working Conditions Survey to identify associations between various working conditions and smoking. We calculated the smoking prevalence depending on individual characteristics and working conditions. Also, multivariate logistic regression analysis was used to investigate the relationship between working conditions and smoking. Results: Company size, occupation type, employment type, working hours, working-time flexibility, and smoking-area policy were related to smoking among male employees, while company size, occupation type, employment type, and smoking-area policy were associated with smoking prevalence among females. Conclusion: Our results indicate that working conditions influence smoking prevalence, and the implementation of smoke-free policies is needed to target specific working conditions, including a strict no-smoking-area policy.

Prevalence and Related Factors of Clonorchiasis among Five Major Riverside Residents in South Korea

  • Kim, Chunmi;June, Kyung Ja;Cho, Shin Hyeong;Park, Kyung Soon;Lee, Hung Sa;Park, Ji Yeon
    • 지역사회간호학회지
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    • 제27권4호
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    • pp.346-357
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    • 2016
  • Purpose: This study attempted to investigate the prevalence and related factors of Clonorchiasis among five major riverside residents in South Korea. Methods: This study is descriptive research, nationwide survey, and the subjects are 23,492 residents selected by convenience sampling. Data collection was conducted between March 1 and June 30, 2011, and stool collection and questionnaire survey were conducted by affiliated public health centers in 38 cities and Gun's. Results: The prevalence rates of Clonorchiasis in the five major riversides were as follows: the Guem River 15.2%; the Nakdong River 11.9%; the Seomjin River 10.9%; the Han River 5.7%; and the Yeongsan River 3.9%. The prevalence rates were shown to be significantly high among people who had highly frequent experiences of eating and cooking freshwater raw fish, were diagnosed with liver and/or biliary tract diseases, and drank less than once a month. Conclusion: These results suggest that it is necessary to improve awareness of Clonorchiasis and provide intensive public health education for the riverside residents. And the target groups should be set up by reflecting the characteristics of at-risk groups, and it is necessary to prepare customized strategies for prevention and management of Clonorchiasis.

소 질병 검출을 위한 혈청학적 검사의 민감도 평가 (Sensitivity analysis of serological tests for detection of disease in cattle)

  • 이상진;문운경;박선일
    • 대한수의학회지
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    • 제50권1호
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    • pp.43-48
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    • 2010
  • Animal disease surveillance system, defined as the continuous investigation of a given population to detect the occurrence of disease or infection for control purposes, has been key roles to assess the health status of an animal population and, more recently, in international trade of animal and animal products with regard to risk assessment. Especially, for a system aiming to determine whether or not a disease is present in a population sensitivity of the system should be maintained high enough not to miss an infected animal. Therefore, when planning the implementation of surveillance system a number of factors that affecting surveillance sensitivity should be taken into account. Of these parameters sample size is of important, and different approaches are used to calculate sample size, usually depending on the objective of surveillance systems. The purpose of this study was to evaluate the sensitivity of the current national serological surveillance programs for four selected bovine diseases assuming a specified sampling plan, to examine factors affecting the probability of detection, and to provide sample sizes required for achieving surveillance goal of detecting at least an infection in a given population. Our results showed that, for example, detecting low level of prevalence (0.2% for bovine tuberculosis) requires selection of all animals per typical Korean cattle farm (n = 17), and thus risk-based target surveillance for high risk groups can be an alternative strategy to increase sensitivity while not increasing overall sampling efforts. The minimum sample size required for detecting at least one positive animal was sharply increased as the disease prevalence is low. More importantly, high reliability of prevalence estimation was expected with increased sampling fraction even when zero-infected animal was identified. The effect of sample size is also discussed in terms of the maximum prevalence when zero-infected animals were identified and on the probability of failure to detect an infection. We suggest that for many serological surveillance systems, diagnostic performance of the testing method, sample size, prevalence, population size, and statistical confidence need to be considered to correctly interpret results of the system.

Epidemiology of trigeminal neuralgia: an electronic population health data study in Korea

  • Lee, Cheol-Hyeong;Jang, Ho-Yeon;Won, Hyung-Sun;Kim, Ja-Sook;Kim, Yeon-Dong
    • The Korean Journal of Pain
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    • 제34권3호
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    • pp.332-338
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    • 2021
  • Background: Trigeminal neuralgia (TN) is one of the most painful disorder in the orofacial region, and many patients have suffered from this disease. For the effective management of TN, fundamental epidemiologic data related to the target population group are essential. Thus, this study was performed to clarify the epidemiological characteristics of TN in the Korean population. This is the first national study to investigate the prevalence of TN in Korean patients. Methods: From 2014 to 2018, population-based medical data for 51,276,314 subscribers to the National Health Insurance Service of Korea were used for this study. Results: The incidence of TN was 100.21 per 100,000 person-years in the year of 2018 in Korea, and the male to female ratio was 1:2.14. The age group of 51-59 years had the highest prevalence of TN. Constant increases in medical cost, regional imbalance, and differences in prescription patterns by the medical specialties were showed in the management of TN. Conclusions: The results in this study will not only help to study the characteristics of TN, but also serve as an important basis for the effective management of TN in Korea.

효율향상 프로그램의 최적 수요관리목표량 산정 (Estimation of Optimal Target Amount for Efficiency Improvement Program of DSM)

  • 소철호;박종진;김진오;조중삼
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2007년도 제38회 하계학술대회
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    • pp.842-843
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    • 2007
  • In this paper, the proper rebate level can be decided in programs of energy savings by solving an optimization problem with an objective function, which satisfies a maximum value of total energy savings. And then, each prevalence amount is estimated by using virtual Bass model which is a function of rebate level, instead of the conventional Bass model. Finally, by cost/benefit analysis of the estimated prevalence amounts, the priority order is obtained for the investment of each program. The priority order obtained in this way may result the improvement of investment efficiency for DSM(Demand-Side Management) programs and the reasonable plan decision for supply and demand in power system.

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우리나라 성인의 관절염 유병 수준과 관련 요인 (Prevalence of Arthritis and Related Factors among Korean Adults)

  • 김순영;남해성;강찬
    • 한국산학기술학회논문지
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    • 제13권9호
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    • pp.4073-4081
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    • 2012
  • 우리나라 성인의 관절염 유병률 수준을 제시하고, 높은 유병율을 보이는 하위집단을 파악하고자 국민건강영양조사 제4기(2007년-2009년) 자료를 이용하여 고유병률 관련 요인을 분석하였다. 통계분석은 국민건강영양조사의 복합표본설계를 반영한 가중치를 적용하기 위해 SAS 9.2 survey procedure로 실시하였다. 19세 이상 성인 18,406명을 대상으로 '연간 본인 인지 관절염'(이하 관절염) 유병률과 사회인구학적 또는 건강행태 요인별 유병교차비를 분석한 결과는 다음과 같다. 관절염 조유병률은 11.7%였고, 이것의 세부 분류인 골관절염은 10.2%, 류마티스관절염은 1.7%의 유병률을 보였다. 19-44세 연령층에서 2.4%, 45-64세 층이 16.4%, 65세 이상에서 38.3%로 연령층 증가에 따라 급격히 증가하였다. 사회인구학적 측면에서 연령보정 관절염 유병률이 상대적으로 높은 집단은 여성, 비아파트 거주자, 이혼 사별 별거 상태인 경우, 낮은 교육년수, 특정직업군(농림어업 종사자, 단순노무종사자, 무직), 낮은 가구총소득, 의료보호 대상자 집단 등이었다. 건강행태 측면에서 연령보정 관절염 유병률이 상대적으로 높은 집단은 체질량지수(BMI)가 높은 집단이었고, 연령, 성, BMI를 보정한 경우 매일 음주군의 유병률이 상대적으로 높았다. 본 연구에서 파악된 고유병률 집단들은 지역사회 관절염 관리사업의 목표집단으로 고려되어야 할 것이다.