• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.34 no.10
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• pp.7-15
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• 2006

The effects of strake incidence-angle on the vortex characteristics and the wing-surface pressure distribution for a double-delta wing with strake were investigated experimentally. The strake incidence-angle of negative sign(strake is pitched down from the main-wing upper-surface) increased the suction pressure of the wing-upper surface, which was the same effect of increase of angle of attack. This change of the suction pressure was caused by the closer movement of the vortex cores to the wing upper surface rather than the increase of the vortex strength.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.22
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• pp.9899-9903
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• 2014

Nasopharyngeal carcinoma (NPC) is an uncommon disease in most countries but occurs with much greater frequency in southern China. This study aimed to examine the secular trends of NPC in urban Guangzhou over the time period of 2000-2011 using data from the Guangzhou Cancer Registry. Age-adjusted annual incidence rates of NPC were calculated by the direct method using the WHO World Standard Population (1960) as the reference. The average annual percentage change (AAPC) was used as an estimate of the trend. A total of 7,532 new cases of NPC and 3,449 related deaths were registered. In both genders, the peak incidence occurred in the 50- to 59-year age group, and this age distribution pattern remained similar throughout. The AAPC in NPC incidence rates was -3.26% (95% CI: -5.4%--1.1) for males and -5.74% (95% CI: -8.9%--2.5) for females, resulting in a total decrease of 39.3% (from 22.14 to 13.44 per 100,000 population) for males and 48.6% (from 10.1 to 5.18 per 100,000 population) for females over this 12-year period. The AAPCs in NPC mortality rates were -4.62% (95%CI: -3.5%--5.7) for males and -6.75% (95% CI: -5.2%--8.3) for females, resulting in a total decrease of -46.1% (from 12.1 to 6.54 per 100,000 population) for males and 51.7% (from 4.14 to 2.00 per 100,000 population) for females. The age-adjusted incidence and mortality rates of NPC declined during 2000-2011 in urban Guangzhou but remained high. Future efforts to improve prevention, early detection and treatment strategies are needed.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.7
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• pp.2653-2657
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• 2015

Nasopharyngeal carcinoma (NPC) is the second most common neoplasm of head and neck in Tunisia. The distribution is bimodal with a first period occurrence between 15 and 20 years old and a second peak at around 50 years of age. Undifferentiated carcinoma of nasopharynx type III (UCNT) is the predominant histological type (93.4%). Data of cancer registry of North Tunisia confirmed that it is an intermediate risk area for NPC with overall ASRs of 3.6 and 1.6/100,000 respectively in males and females. This study aimed to present the evolution of incidence rate of nasopharyngeal carcinoma over a period of 12 years (1994-2006). Data of cancer registry of North Tunisia (NTCR), covering half of the Tunisian population, were used to determine evolution of NPC incidence, calculated by 5 year periods. The estimated annual percentage change (EAPC) was used as an estimate of the trend. To best summarize the behavior or the data trend across years, we used a join-point regression program. Between 1994 and 2006, we observed negative annual average change of standardized incidence in men and women (-3.3%and -2.7%) also for the standardized incidences which showed a rather important decline (26.4% in males and 22.3% in females). The truncated age standardized incidence rate of NPC in adults aged of 30 years old and more (N= 1209) decreased by -0.4% per year from 1994 to 2006 over time in north Tunisia dropping from 6.09 to 4.14 person-years. However, the rate was relatively stable during this period among youths aged 0-29 years (N= 233) in both sexes. NPC demonstrated a favorable evolution from 1994-2006 probably due to a improvement in socioeconomic conditions.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.10
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• pp.4447-4450
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• 2015

Background: Nasopharyngeal cancer is a disease with distinct ethnic and geographical distribution. The aim of this review was to describe the epidemiological characteristics of nasopharyngeal cancer in Iran from 2004 to 2009 because no systematic study has been performed to evaluate the trends of its incidence yet. Materials and Methods: The data were derived from the databases of the National Cancer Data System Registry in the period of 2004-2009. Nasopharyngeal cancers were classified according to the International Classification of Diseases for Oncology. Incidence rates and trends were calculated and evaluated by gender, age decade, and histopathology types. Results: A total of 1,637 nasopharyngeal cancers were registered in Iran from 2004 to 2009 giving an incidence of 0.38 per 100,000. The male-to-female ratio was 2.08:1. The trend of incidence was found to have increased, with a significant increase observed in males. Undifferentiated carcinoma was the most common histopathology type in all the age decades. Conclusions: Because the incidence of nasopharyngeal cancers in Iran has increased, especially in males, further studies are recommended for understanding of the etiological factors involved in the rise of the disease.

• Journal of Preventive Medicine and Public Health
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• v.42 no.4
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• pp.261-266
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• 2009

Objectives : The aim of this study is to examine the cognitive function change related to aging, the incidence of cognitive impairment, and the association between apolipoprotein E polymorphism and cognitive impairment through a follow-up of the elderly with normal cognitive ability at baseline. Methods : Two hundred and fifteen subjects aged 65 and over were surveyed in February, 1998 (baseline survey), and their cognitive function was assessed again in 2003 1st follow-up) and the once again in 2006 (2nd follow-up). Ninety one subjects completed all surveys up through the 2nd follow-up and their cognitive function scores using MMSE-K (Korean Version of the Mini-Mental State Examination) and the distribution of apolipoprotein E allele were analyzed. Results : The cognitive function scores decreased with aging and the difference between baseline and the 2nd follow-up scores of the study increased with the age group. The incidence rate of cognitive impairment through an 8-year follow-up was 38.5% and higher in older age groups. Age was the only significant factor for incidence of cognitive impairment, but there was no significant association between apolipoprotein E genotype and incidence of cognitive impairment. Conclusions : The cognition of the elderly decreased with aging and the association of apolipoprotein E genotype with incidence of cognitive impairment was not significant in this study. To confirm the association between apolipoprotein E polymorphism and incidence of cognitive impairment further studies will be needed.

• Journal of the Korean Data and Information Science Society
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• v.20 no.1
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• pp.149-158
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• 2009

Tsutsugamushi fever occupies more than 80% of total fall epidemic diseases and has an incubation period of 1 or 2 weeks as well. We have assumed that the incubation period distribution is gamma and therefore, reach an agreement that the infected distribution is normal with ${\hat{\mu}}=309.92$, ${\hat{\sigma}}=14.154$ by back calculation method. The infection cases are found severely large around the month of October. The infection case distribution demonstrates the incidence number increasing rapidly and progresses fast during the month of November. In this study, we have calculated the future prevalence number of maximum 1,200 people by inferred infection probability and incubation period distribution with some sort of limitation that the trend of increasing incidence number is not taking into an account. We considered the SIRS model which is also known as epidemic model, familiar to interaction between epidemiological classes. Our estimated parameters converged well with the initial parameter values.

• Journal of KSNVE
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• v.7 no.6
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• pp.945-952
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• 1997

This paper shows the feasibility of the suggestion that the angle distribution of incident sound to panels might be gaussian, instead of the conventional uniform distribution in the analysis of transmission loss of panels. To prove the suggestion, the problems with the diffuse sound field in a reverberation room are examined by case studies and the comparision of the prediction with the measurement of sound transmission loss of walls are performed. The results of the comparision show good agreement between the two values.

• Journal of Periodontal and Implant Science
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• v.20 no.2
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• pp.159.1-159.1
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• 1990

• Journal of Periodontal and Implant Science
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• v.13 no.1
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• pp.67.2-67.2
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• 1983

• Journal of Preventive Medicine and Public Health
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• v.22 no.2 s.26
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• pp.276-282
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• 1989

The objective of this study was to examine the impact of changes in maternal age and parity distribution on birth weight. The study population included 7,786 single live births in 1977 and 8,671 single live births in 1987 delivered at 9 medical facilities in Pusan. Data were obtained from the delivery record. The proportion of infants born to the mothers of 25-29 years increased from 56.475 in 1977 to 65.1% in 1987 and the proportion to the mothers of 30-34 years increased from 18.8% in 1977 to 21.6% in 1987. In the same period, the proportions of 1st and 2nd birth order were increased from 56.9% and 28.8% to 59.9% and 36.8%, respectively. The proportion of infants born to the age group of ${\leq}24\;and\;35{\leq}$ years were decreased in 1987. The proportion of births of the third or higher birth order was decreased from 14.2% in 1977 to 3.3% in 1987. Low birth weight (<2500gm) incidence rate was 5.3% in 1977 and it was decreased to 4.0% in 1987. It was estimated that changes in maternal age-parity distribution accounted for 10.7% of the decreased in low birth weight incidence rate. Rest of the change (89.3%) was attributed to the reduction of age-parity specific low birth weight incidence rate. Application of the direct adjustment method was considered to be an adequate tool for evaluating the impact of family planning on neonatal health.