• Asian Pacific Journal of Cancer Prevention
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• v.13 no.8
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• pp.3911-3916
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• 2012

Background: The objective of this study WAS to describe cancer incidence rates and trends among THE Hong Kong population for the period 1983-2008. Methods: Incident cases and population data from 1983 to 2008 were obtained from the Hong Kong Cancer Registry and the Census and Statistics Department, respectively. Agestandardized incidence rates (ASIR) were estimated and joinpoint regression was applied to detect significant changes in cancer morbidity. Results: For all cancers combined, the ASIR showed declining trends (1.37% in men, 0.94% in women), this also being the case for cancers of lung, liver, nasopharynx, stomach, bladder, oesophagus for both genders and cervix cancer for women. With cancer of thyroid, prostate, male colorectal, corpus uteri, ovary and female breast cancer an increase was evident throughout the period. The incidence for leukemia showed a stable trend since early 1990s, following an earlier decrease. Conclusion: Although overall cancer incidence rates and certain cancers showed declining trends, incidence trends for colorectal, thyroid and sex-related cancers continue to rise. These trends in cancer morbidity can be used as an important resource to plan and develop effective programs aimed at the control and prevention of the spread of cancer amongst the Hong Kong population. It is particularly useful in allowing projection of future burdens on the society with the increase in certain cancer incidences.

• Journal of the Korean Institute of Telematics and Electronics S
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• v.36S no.10
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• pp.103-112
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• 1999

Genetic algorithm, which uses principles of natural selection and population genetics, is an efficient method to find out an optimal solution. In conventional genetic algorithms, however, the size of gene pool needs to be increased to insure a convergency. Therefore, many memory spaces and much computation time were needed. Also, since child chromosomes were generated by chromosome crossover and gene mutation, the algorithms have a complex structure. Thus, in this paper, a compact stereo matching algorithm using a population-based incremental learning based on probability vector is proposed to reduce these problems. The PBIL method is modified for matching environment. Since th proposed algorithm uses a probability vector and eliminates gene pool, chromosome crossover, and gene mutation, the matching algorithm is simple and the computation load is considerably reduced. Even though the characteristics of images are changed, stable outputs are obtained without the modification of the matching algorithm.

• The Korean Journal of Ecology
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• v.21 no.1
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• pp.27-33
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• 1998

Arisaema robustum, which has the ability to change sex, was studied in a temperate broadleaf forest of Sanseong-ri, Joongbu-myeon, Gwangju-gun, Kyonggi Province, Korea. \ulcornerThe study, carried out from 1993 to 1997, focused on population dynamics energy budget among organs, size distribution, mortality, the relationships between sex and size, seed production and germination rate. In terms of energy budget among the organs, the ratio of aboveground to belowground biomass was 36.6 : 63.4 in non-female plants, and 81.4 : 18.6 in female plants. Also, in female plants, the ration of leaf to sexual organ biomass was 39.5 : 41.9. Therefore, the belowground ratio of female plants was lower than that of non-female plants. Plants were classified into 8 levels relative to the amount of leaf area by $100cm^2$. The rates of the smallest and the largest classes were 49% and 1%, respectively, and population distribution by size was relatively stable. The mortality averaged 13.1% per year and decreased in inverse proportion to leaf size (6.6% in the smallest and 0.0% in the largest size classes). Leaf areas were $64.1{\pm}48.5cm^2$ in non-flowering plants, $232.1{\pm}123.9cm^2$ in males and $444.8{\pm}153.9cm^2$ in females. The increase rates of leaf area per year varied from 1.9% in plants changing from female tomale, to 152.4% in plants changing from non-flowering to female. But plants which remained female for 2 years showed a decrease of 34.7%. >From this result, it is thought that the female plants invest more energy to reproduction than to vegetative organs. The correlation coefficient (CC) value between plant size and the number of seeds produced (0.55) was larger than the CC value between plant size and total seed weight (0.73). That is, the larger the plant size, the heavier the seed produced. The germination rate increased along with seed weight, and it was 95% in plants which were over 60mg fresh weight/seed.

• Journal of Korean Dental Hygiene Science
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• v.3 no.2
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• pp.51-58
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• 2020

Oral examination ensures early detection and treatment of oral diseases and improvement of quality of health-related life. This is imperative as it reduces individuals' dental medical expenses and social costs caused by diseases. However, as the low oral examination acceptance rate continues to be a problem, this study was conducted to identify the factors that influence the oral examination of an economically active population. In this study, 4,836 economically active individuals between the ages of 20 and 65 years were studied using data from the 7th National Health and Nutrition Survey in 2018. Logistic regression analysis was performed to determine the factors influencing demographic and sociological characteristics on oral examination after adjusting for complaints of mastication and speech discomfort. As a result of confirming the factors influencing the oral examination, increase in age tended to be inversely proportional to the oral examination. Income level, type of job, and job position were identified as factors that influenced oral examinations. Compared to the group with a high socioeconomic status, which is represented by a group with a high income level or a stable job type or job position, the group with low economic status was found to have a negative effect on oral examination. Oral management of vulnerable groups, who might not be considered while devising oral health management policies, should be promoted through the development and provision of oral health management policies that consider employment status and environment.

• ALGAE
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• v.37 no.2
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• pp.123-133
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• 2022

Genetic diversity and distribution patterns of marine macroalgae are increasingly being documented in Southeast Asia. These studies show that there can be significant levels of genetic diversity and isolation between populations on either side of the Thai-Malay Peninsula. Bostrychia tenellla is a common filamentous red seaweed in the region and the entity is represented by at least two cryptic species. Despite being highly diverse and widespread, genetic variation and population structure of this species complex remains understudied, especially around the Thai-Malay Peninsula. We analyzed genetic diversity and inferred the phylogeographic pattern of specimens identified as B. tenella using the plastid RuBisCo spacer from samples from the Andaman Sea and the Gulf of Thailand. Our genetic analysis confirmed the occurrence of the two cryptic B. tenella species (B and C) along both coasts. Cryptic species B was more common in the area and displayed higher genetic diversity than species C. Historical demographic analyses indicated a stable population for species B, but more recent population expansion for species C. Our analyses also revealed that both cryptic species from the Andaman Sea possessed higher genetic diversity than those of the Gulf of Thailand. We also detected moderate to high levels of gene flow and weak phylogeographic structure of cryptic species B between the two coasts. In contrast, phylogeographic analysis showed genetic differences between populations of both cryptic species within the Andaman Sea. Overall, these results suggest that cryptic B. tenella species around Thai-Malay Peninsula may have undergone different demography histories, and their patterns of genetic diversity and phylogeography were likely caused by geological history and regional sea surface current circulation in the area.

• Journal of Information Technology Applications and Management
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• v.30 no.1
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• pp.33-52
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• 2023

This study observes the difference in the actual regional ripple effect of the decrease in admission resources due to the decrease in school age population, which has been weak in empirical studies, and how much the decrease in competition rate by department nationwide provides a significant shock to the decrease in enrollment rate in the population unit. An empirical quantitative analysis was attempted. As a result of applying the panel-tobit regression model, a clear gap was confirmed in the decrease in the registration rate due to the decrease in the competition rate both nationally and in the provinces, and in particular, a highly significant relationship was derived with the decrease in the recruitment rate. In particular, the sensitivity of the risk of unrecruitment due to a decrease in competition rate was the highest in the Jeolla region (0.499), followed by the Gangwon region (0.475) and the Gyeongsang region (0.471), and the metropolitan region (0.158) was confirmed to be the most stable. This suggests that the gap in insufficient funding has gradually widened by region over the past 10 years, and that the shock wave becomes more pronounced in the provinces farther away from the metropolitan area. Based on this study, if we deviate from the standardized application of university development policies for the metropolitan area and regional universities, and present a customized higher education strategy for each region, it will be an opportunity to prevent local extinction due to a decrease in the school-age population and achieve coexistence with higher education institutions and regions at the same time.

• Current Research on Agriculture and Life Sciences
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• v.7
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• pp.201-219
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• 1989

Rice culture in Korea has a long history ranging over two thousand years. In the agriculture economy of pre-mordern Korea, however, its importantce was not as great as generally assumed. In fact, rice culture reached full development only after the 1920s when the Japanese colonial government carried out its drive to increase rice production in the Korea peninsula. It was not until the mid-1930s that rice became the staple in Korean diet. This can be attributed to two factors : (1) a mountainous topography that provides little irrigated fields and (2) a climate characterized by droughts in spring and heavy precipitation in summer. The present paper attempts to answer some of these questions. Specifically it will focus on these : Did the development of rice culture actually result in population growth? What are the salient features of agricultural develdpment and population grow in traditional Korea? Does the case of Korea conform the prevailing generalization about the agriculture in East Asia? I have discussed the development of rice culture and population growth in the Chos$\breve{o}$n dynasty, focusing on the relation between the rapid spread of transplanting and the rapid growth of population from the seventeenth to the nineteenth century. Here are my conclusions. (1) The spread of transplanting and other technological innovationsc contributed to the rapid growth of population in this period. However, we should also note that the impact of rice culture on population growth was rather limited, for rice culture was not the mainstay of agricultural economy in pre-modern Korea. Indeed we should consider the influence of dry field cropsn population growth. Nevertheless, it is obvious that the proliferation of rice culture was a factor crucial to population growth and regional concentration. (2) How should we characterize the spread of rice culture in the whole period? Evidently rice culture spread from less then 20% of cultivated fields in the fifteenth century to about 36% of them in the early twentieth century. Although rice as a single crop outweighed other crops, rice culture was more then counter-balanced by dry field crops as a whole, due to Korea's unique climate and geography. Thus what we have here in not a typical case of competition between rice culture and day field culture. Besides, the spread of rice culture in the seventeenth and eighteenth centuries accomplished by technological innovations that overcame severe springtime drought, rather than extensive irrigation. Althougt irrigarion facilities did proliferate to some extent, this was achieved by local landlords and peasants rather than the state. This fact contradicts the classical thesis that the productivity of rice culture increased through the state management of irrigation and that this in turn determined the type of society. (3) We should further study other aspects of the transition from the stable population and production struture in the fifteenth and sixteenth centuries to the rapid population growth and excessive density of population thereafter. We should note that there were continuing efforts to reclaim the land in order to solve the severe shortage of land. Changes also took place in the agricultural production relations. The increase in land producrivity developed tenancy based on rent in kind, and this in turn increased the independence of tenants from their landlords. There were changes in family relations-such as the shift to primogeniture as an effort to prevent progressive division of property among multiplying offspring. The rapid population growth also produced a great mass of propertyless farm laborers. These changes had much to do with the disintegration of traditional social institutions and political structure toward the end of the Chos$\breve{o}$n dynasty.

• Analytical Science and Technology
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• v.32 no.6
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• pp.262-270
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• 2019

The stable isotopic composition of bone collagen plays an important role in reconstructing palaeodiet, nutrition, palaeoenvironment and their lifestyle. This is the first case in extracting palaeodietary information and breastfeeding pattern of Goryeo people using stable isotope analysis due to the lack of human remains in this period. We analyzed human bone collagen excavated from Gyeongju Donggung palace and Wolji pond No.3. The average values of δ¹³C and δ¹⁵N are as follows: (δ¹³C(‰) = -19.5 ± 0.9‰, δ¹⁵N(‰) = 11.1 ± 1.1 ‰, (n = 4). Stable carbon isotope values shows a mainly C₃ based diet such as rice and barley. Stable nitrogen isotope results implies the protein sources attributed to terrestrial animals. There are various age groups in this study, which are adult, child and infant. Two individuals within early childhood age ranges (< 3 years) shows more elevated δ¹⁵N values than that of adult and this result implies the continuation of breastfeeding in this group until the age of 3. The results provide new insight into the breastfeeding pattern of Goryeo people, where breastfeeding and weaning practices have important implication for fertility, population dynamics, migration pattern and disease.

• Journal of Oriental Medical Thermology
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• v.1 no.1
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• pp.28-37
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• 2002

Stable Compression Fractures(SCF hereafter) are most often caused by trauma such as traffic accidents. These SCFs usually occur in the thoracic and lumbar regions of the spinal cord. Human life spans have increased as a result of medical advances, which in turn has led to an increase in the elderly population. SCFs are divided into the categories of stable and unstable. The categories are determined through X-rays and P/Ex tests. The D.I.T.I. is then used to diagnose the severity and prognosis of the fracture injuries, and it allows an objective evaluation of the symptoms. This author researched 40 patients who were treated at Wonkwang University Oriental Medical Center from October 1995 to December 1996. The patients were diagnosed by X-ray as having SCFs and treated primarily with acupuncture. Both the changes in D.I.T.I. and patients' self-diagnoses of their conditions before and after treatment yielded the meaningful results which have been presented here. 1. 75% of those who suffer from Stable Compression Fractures are 60 years of older. Of those, the ratio of male to female is 1 to 4. This is due in part to the fact that many elderly women seek Oriental medicine treatment for conditions associated with advanced age. 2. 53.3% of these injuries occurred between T11 and L2. 3. 65% of patients were hospitalized for 10 to 29 days, and then able to be treated on an outpatiens basis. 4. The D.I.T.I. results showed 50% below $0.2^{\circ}C$, 30% between 0.3 and $0.5^{\circ}C$, 10% between 0.5 and $0.7^{\circ}C$, 10% between 0.7 and $0.9^{\circ}C$, and 0% over $0.9^{\circ}C$. 5. The results of treatment using Modified Evaluation System in Thoracolumbar Vertebral Fractures Method showed that 55% of patients achieved excellent recovery and 40% achived good recovery. After comparing the D.I.T.I. results before and after treatment, we found 50% of patients showed excellent recovery $({\Delta}T{\leq}0.2)$ and 40% showed good recovery$(0.2<{\Delta}T{\leq}0.5)$.

• Korean Journal of Environment and Ecology
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• v.27 no.4
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• pp.417-428
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• 2013

The red fox (Vulpes vulpes), listed as a Class I endangered species by the Ministry of Environment of Korea, has been considered to be extinct in South Korea since the 1980s, and an intensive restoration project has been underway in Sobaeksan national park. This study was carried out to develop a suitable model for the red fox reintroduction program based on Population viability analysis (PVA) by using the VORTEX program. If 10 animals (5 females and 5 males) were continuously released into the initial zero population every year for 10 years, population growth rate and extinction probability over the next 50 years after the introduction of the population were $0.018{\pm}0.204$ and 0.354, respectively; the maximum population size was 116.34 at the 16th year after the first release, and a reduction rate of 1.22 every year from the 17th year was inferred. We found that additional releases would be needed from the 17th year after the initial release to maintain a positive growth rate and to prevent the extinction of the released red foxes, and releasing more than 12 individuals every year would be needed for the long-term, continuous existence of red foxes. By contrast, if fewer than 6 red fox individuals were released the extinction probability over the next 50 years was more than 80%. To maintain the minimum population growth rate, the release of more than 8 individuals were needed for positive population growth. The population growth rate was more stable when 10 animals in the change of their sex rate every year from the set value were released as the female-to- male sex ratio of 6:4 rather than 1:1. However, if the female-biased sex ratio was increased by more than 7:3, a negative population growth was expected. The occurrence rate of roadkill and poaching are important factors in the red fox restoration project. The extinction probability was decreased to 30% if each factor was decreased to 3% based on the standard baseline; however, if each factor was increased to more than 3%, an extinction rate of about 90% was reached over the next 50 years.