• Asian Pacific Journal of Cancer Prevention
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• v.17 no.sup3
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• pp.47-52
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• 2016

Breast cancer is the most common malignancy in women in Asia and its incidence is rapidly increasing. Information on the incidence and mortality of breast cancer is essential for planning health and more studies. This study aimed to investigate the age-specific incidence and mortality of breast cancer in Asia in 2012. A total of 639,824 cases of breast cancer were recorded in Asian countries, those with the five highest standardized incidence rates being Israel, Lebanon, Armenia, Singapore, and Kazakhstan. The highest number of deaths was observed in India, China, Indonesia, Pakistan, and Japan, respectively. Tith increasing income and improving living standards in developing countries, the incidence of breast cancer increases. This may be due to longer life, higher exposure to risk factors, eating more fatty foods and obesity, and lower pregnancy rates. The variation in incidence rates of breast cancer is very pronounced in Asia (from 80.5 in Israel to 4.6 in Bhuta). A similar situation exists for mortality rates (from 1.8 in Bhutan to 25.2 in Pakistan).

• Transactions of the Korean Society of Mechanical Engineers B
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• v.31 no.4
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• pp.349-356
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• 2007

The present study investigated local heat/mass transfer characteristics on the tip of the rotating turbine blade with various incoming flow incidence angles. The experiments are conducted in a low speed annular cascade with a single stage turbine. The blade has a flat tip with a mean tip clearance of 2.5% of the blade chord. The incoming flow Reynolds number is $1.5{\times}10^5$ at design condition. To examine the effect of off-design condition, the experiments with various incidence angles ranging between $-15^{\circ}$ and $+7{\circ}$ were conducted. A naphthalene sublimation method is used to measure detailed mass transfer coefficient on the blade. The results indicated that the incidence angle strongly affects the behavior of tip leakage flow around the blade tip and consequently plays an important role in determining heat transfer characteristics on the tip. For negative incidence angles, the heat/mass transfer in the upstream region on the tip decreases by up to 20%. On the contrary, for positive incidence angles, much higher heat transfer coefficients are observed even with small increase of incidence angle.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.31 no.4
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• pp.357-366
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• 2007

The present study investigated local heat/mass transfer characteristics on the surface of the rotating turbine blade with various incidence angles. The experiments are conducted in a low speed annular cascade with a single stage turbine. The blade has a flat tip with the mean tip clearance of 2.5% of the blade chord. A naphthalene sublimation method is used to measure detailed mass transfer coefficient on the blade. At design condition, the inlet Reynolds number is $Re_c=1.5{\times}10^5$ which results in the blade rotation speed of 255.8 rpm. Also, the effect of off-design condition is examined with various incidence angles between $-15^{\circ}$ and $+7{\circ}$. The results indicated that the incidence angle has significant effects on the blade surface heat transfer. In mid-span region, the laminar separation region on the pressure side is reduced and the laminar flow region on the suction side shrinks with increasing incidence angle. Near the tip, the effect of tip leakage flow increases in span wise and axial directions as the incidence angle decreases because the tip leakage flow is formed near the suction side surface. However, the effect of tip leakage flow is reduced with positive incidence angle.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.14 no.1
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• pp.89-98
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• 1984

The purpose of the present study is to offer the fundamental materials for the diagnosis of dentigerous cyst by analysis of the clinical and radiographic findings of these lesions. The subject for this study consisted 118 patients admitted to the Department of Oral Radiology, Kyung Hee University and Seoul National University from 1974 to 1983. Conclusions from this study were as follows: 1. There was a higher incidence in males (70.34%) than in females (29.66%), and the incidence was highest in the second and third decade (26.27%) with the same incidence. (Average age: 25 year) 2. There was a higher incidence in the maxillary teeth (66.10%) than in the mandibular teeth (33.90%) and the maxillary supernumerary tooth (45.76%) was the most frequently involved one. The mandibular third molar (16.10%) was next in order of frequency of involvement followed by maxillary canine (7.63%), mandibular second premolar (5.08%). 3. There was a greater incidence of the central type than the lateral type in the maxilla, while a higher incidence of the lateral type in the mandible. 4. There was a greater incidence of the smooth type (84.26%) than that of the scalloped type (15.74%) and a higher incidence of minor type (70.91%) than the major type (29.09%) in the displacement of associated tooth. 5. Root apices of teeth encompassed or approached by the cysts showed variable resorption in 68.47% of cases.

• Journal of Applied Reliability
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• v.16 no.1
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• pp.56-63
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• 2016

Purpose: The purpose of this study is to point out that the Kaplan-Meier method is not valid to calculate the survival probability or failure probability (risk) in the presence of competing risks and to introduce more valid method of cumulative incidence function. Methods: Survival analysis methods have been widely used in biostatistics division. However the same methods have not been utilized in reliability division. Especially competing risks cases, where several causes of failure occur and the occurrence of one event precludes the occurrence of the other events, are scattered in reliability field. But they are not noticed in the realm of reliability expertism or they are analysed in the wrong way. Specifically Kaplan-Meier method which assumes that the censoring times and failure times are independent is used to calculate the probability of failure in the presence of competing risks, thereby overestimating the real probability of failure. Hence, cumulative incidence function is introduced and sample competing risks data are analysed using cumulative incidence function and some graphs. Finally comparison of cumulative incidence functions and regression type analysis are mentioned briefly. Results: Cumulative incidence function is used to calculate the survival probability or failure probability (risk) in the presence of competing risks and some useful graphs depicting the failure trend over the lifetime are introduced. Conclusion: This paper shows that Kaplan-Meier method is not appropriate for the evaluation of survival or failure over the course of lifetime. In stead, cumulative incidence function is shown to be useful. Some graphs using the cumulative incidence functions are also shown to be informative.

• Health Policy and Management
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• v.32 no.1
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• pp.45-52
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• 2022

Background: There are regional variations in the incidence of coronavirus disease 2019 (COVID-19), which means that some regions are more exposed to the risk of COVID-19 than others. Therefore, this study aims to investigate regional variations in the incidence of COVID-19 in Korea and identify risk factors associated with the incidence of COVID-19 using community-level data. Methods: This study was conducted at the districts (si·gun·gu) level in Korea. Data of COVID-19 incidence by districts were collected from the official website of each province. Data was also obtained from the Korean Statistical Information Service and the Community Health Survey; socio-demographic factor, transmission pathway, healthcare resource, and factor in response to COVID-19. Community risk factors that drive the incidence of COVID-19 were selected using a least absolute shrinkage and selection operator regression. Results: As of June 2021, the incidence of COVID-19 differed by more than 80 times between districts. Among the candidate factors, sex ratio, population aged 20-29, local financial independence, population density, diabetes prevalence, and failure to comply with the quarantine rules were significantly associated with COVID-19 incidence. Conclusion: This study suggests setting COVID-19 quarantine policy and allocating resources, considering the community risk factors. Protecting vulnerable groups should be a high priority for these policies.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.25 no.3
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• pp.276-282
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• 2022

Purpose: Infantile colic, a common functional gastrointestinal condition, causes distress and frustration in families. Its prevalence and incidence vary from community to community. The purpose of our study was to demonstrate the incidence of and factors associated with infantile colic in Thai infants. Methods: We conducted a prospective analytic study to explore the incidence and factors associated with infantile colic in 386 Thai infants aged between one month and six months. Caregivers were interviewed using a questionnaire about infants' symptoms of colic based on the definition from the Rome IV criteria. Family background and potential precipitating factors of colic were also evaluated. Results: The incidence of colic in infants younger than 6 months was 6.5%. All infants' colic started within 12 weeks of life and lasted approximately 6 weeks. Sex, gestational age, birth weight, delivery route, birth order, family factors, and parental factors were not correlated with the occurrence of colic. Infants who were exclusively breastfed for the first 2 months of life had a lower incidence of infantile colic than those who were mixed- or formula-fed (odds ratio=3.0; 95% confidence intervals=1.3 to 7.2). Conclusion: The incidence of infantile colic in Thai infants in our study was 6.5%, which is similar to that in other reports. Being exclusively breastfed for the first two months was the only risk factor in our cohort.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.9
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• pp.4613-4617
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• 2012

National cancer incidence data were utilized to analyze trends in esophageal cancer incidence in China in order to provide basic information for making cancer control strategy. We retrieved and re-sorted valid esophageal cancer incidence data from National Central Cancer Registry Database over 20 years period from 1989 to 2008. Crude incidence and age-standardized incidence rates were calculated for analysis, with annual percent change estimated by Joinpoint software for long term trend analysis. The crude incidence rate of esophageal cancer was found to have remained relatively stable in both urban and rural areas over the 20 year period. Age standardized incidence rate (ASR) in cancer registration areas decreased from 39.5/100,000 in 1989 to 23.0/100,000 in 2008 in all areas (AAPC=-3.3%, 95% CI:-2.8~-3.7). The trend was no change in urban areas and 2.1% average annual decrease observed in rural aras. Before the year of 2000, esophageal cancer incidence rates significant decreased with 2.8% annually and then the rates kept stable. Over 20 years from 1989 to 2008, esophageal cancer age standardized incidence rate in cancer registration areas decreased with time. However, esophageal cancer is still a big issue and efforts for control should be continuously enhanced. Cancer registration is playing an important role in cancer control with the number of registries increasing and data quality improving in China.

• Environmental Analysis Health and Toxicology
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• v.31
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• pp.3.1-3.11
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• 2016

Objectives This study was conducted to describe the regional malaria incidence in relation to the geographic and climatic conditions and describe the effect of altitude on the expansion of malaria over the last decade in Papua New Guinea. Methods Malaria incidence was estimated in five provinces from 1996 to 2008 using national health surveillance data. Time trend of malaria incidence was compared with rainfall and minimum/maximum temperature. In the Eastern Highland Province, time trend of malaria incidence over the study period was stratified by altitude. Spatio-temporal pattern of malaria was analyzed. Results Nationwide, malaria incidence was stationary. Regionally, the incidence increased markedly in the highland region (292.0/100000/yr, p =0.021), and remained stationary in the other regions. Seasonality of the malaria incidence was related with rainfall. Decreasing incidence of malaria was associated with decreasing rainfall in the southern coastal region, whereas it was not evident in the northern coastal region. In the Eastern Highland Province, malaria incidence increased in areas below 1700 m, with the rate of increase being steeper at higher altitudes. Conclusions Increasing trend of malaria incidence was prominent in the highland region of Papua New Guinea, while long-term trend was dependent upon baseline level of rainfall in coastal regions.

• Clinical and Experimental Pediatrics
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• v.51 no.6
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• pp.569-575
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• 2008

Type 1 diabetes mellitus (T1 DM) develops in genetically susceptible individuals as a result of progressive autoimmune destruction of beta cells. There is larger global variation in incidence among children aged 0-14 years. The incidence of T1 DM in Korea is very low. The latest survey in Korea was conducted in 2001 by Korean Society of Pediatrics to analyse the childhood (0-14 years) national-wide incidence during 1 995-2000. The average childhood incidence (/100,000 and year) was 1.36 (95% CI: 1.23-1.48), higher than 1.06 of Korea in 1 994. This survey reported that higher mean annual incidence was observed in female (girls, 1.67 vs boy 1.07), older age group (10-14 years, 1.98; 5-9 years, 1.43; 0-4 years, 0.73), Kangwondo (2.09) and Seoul (1.99), and more new patients developed in spring (spring, 27.1%; winter, 26.6%; summer, 24.8%; autumn, 21.5%). The increase of childhood T1 DM incidence has occurred in every region (4.0% in Asia, 3.2% in Europe during 1990-1999). Also, steady increase in incidence was observed during 1985-2000 in Korea. This trends may be maintained or accelerated by environmental factors, known as triggers, modifiers and promoters of the T1 DM occurrence. The rising incidence of T1 DM suggests the need for continuous monitoring of incidence by using standardized methods in order to plan or assess prevention strategies.