• 제목/요약/키워드: population change

검색결과 1,805건 처리시간 0.024초

Moth (Insecta: Lepidoptera) Biodiversity on Island Oenarodo, Goheung-gun, Jeonnam (전라남도 고흥군 외나로도 나방(곤충강: 나비목)의 생물다양성 연구)

  • An, Jeong-Seop;Park, Ma-Ra-Na;Kang, Eun-Seok;Choi, Sei-Woong
    • Korean Journal of Environmental Biology
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    • 제26권3호
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    • pp.192-202
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    • 2008
  • The present study aimed to investigate the local moth fauna and population change during a year on Island Oenarodo (N34$^{\circ}$27'50", E127$^{\circ}$28'06", 74 m a. s. l.), Goheung-gun, Jeonnam. Moth collecting was carried out using a light trap from March to October, 2007. A total of 231 species and 562 individuals in 14 families were identified. Species of Noctuidae were the most abundant with 86 species and 163 individuals, followed by Geometridae (60 species and 147 individuals) and Pyralidae (39 species and 135 individuals), respectively. Monthly changes of moths species richness and abundance were M-shaped with two peaks at late Spring and late Summer. During the study, a geometrid, Menophra senilis, and a pyralid, Endotricha olivacealis were most abundant with 16 individuals. The estimated species richness using Chao 1 identified 646 species, suggesting that we need more extensive and long-term survey for the better understanding of the total moth fauna on the island.

A Study on Teaching Method of Two-Sample Test for Population Mean Difference (두 모집단 모평균 비교의 지도에 관한 연구)

  • Kim Yong-Tae;Lee Jang-Taek
    • The Mathematical Education
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    • 제45권2호
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    • pp.145-154
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    • 2006
  • The main purpose of this study is to investigate the effect of departures from normality and equal variance on the two-sample test when the variances are unknown. We have found that type I error brought about a little bit change which is ignorable in relation to kurtosis. But the change of type I error was mainly based on the skewness of the parent population. In introductory statistics classes where data analysis includes techniques for detecting skewness of two populations, we recommend the two-sample t-test when maximal skewness of two populations is smalter than the value 4 when the variances seem equal. Furthermore, our simulations reveal that the two-sample t-test appears somewhat more robust than that of z-test if the assumption of equal variance is satisfied. In the case of unequal variance, the two-sample t-test appears somewhat more robust provided the t-statistic using Satterthwaite's approximate degrees of freedom.

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Population Changes of Moths (Insecta: Lepidoptera) from Mt. Wolchul National Park, Jeollanam-do, Korea

  • Choi, Sei-Woong;Park, Marana;Chang, Young-Hyo
    • Journal of Ecology and Environment
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    • 제30권3호
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    • pp.245-250
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    • 2007
  • We investigated the moth fauna and monthly changes in moth populations at three sites - Dogapsa, Gyungpodae and Muwisa - in Mt. Wolchul National Park, Jeollanam-do, South Korea. From February to October, 2006, we collected a total of 1677 individuals comprising 348 species in 14 families. Monthly changes in the abundance of species and individuals showed an M-shaped pattern, with the highest peak in June and a second high peak in August. The diversity of the three dominant families (Noctuidae, Geometridae and Pyralidae) at the three sites varied, possibly due to differences in vegetation and other environmental factors. Diversity at Dogapsa was relatively higher than Gyungpodae and Muwisa, but, the fauna at Dogapsa more closely resembled Muwisa than Gyungpodae. 28 species occurred at the same time in all three sites, included the families Geometridae (14 species), Noctuidae (9 species), Pyralidae (2 species), Arctiidae (1 species), Nolidae (1 species), and Limacodidae (1 species). The present study provided baseline information about biodiversity and phenological patterns of moth abundance and permitted evaluation of moth biodiversity as a monitoring tool for vegetation structure and environmental change.

An empirical investigation of nuclear energy consumption and carbon dioxide (CO2) emission in India: Bridging IPAT and EKC hypotheses

  • Danish, Danish;Ozcan, Burcu;Ulucak, Recep
    • Nuclear Engineering and Technology
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    • 제53권6호
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    • pp.2056-2065
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    • 2021
  • The transition toward clean energy is an issue of great importance with growing debate in climate change mitigation. The complex nature of nuclear energy-CO2 emissions nexus makes it difficult to predict whether or not nuclear acts as a clean energy source. Hence, we examined the relationship between nuclear energy consumption and CO2 emissions in the context of the IPAT and Environmental Kuznets Curve (EKC) framework. Dynamic Auto-regressive Distributive Lag (DARDL), a newly modified econometric tool, is employed for estimation of long- and short-run dynamics by using yearly data spanning from 1971 to 2018. The empirical findings of the study revealed an instantaneous increase in nuclear energy reduces environmental pollution, which highlights that more nuclear energy power in the Indian energy system would be beneficial for climate change mitigation. The results further demonstrate that the overarching effect of population density in the IPAT equation stimulates carbon emissions. Finally, nuclear energy and population density contribute to form the EKC curve. To achieving a cleaner environment, results point out governmental policies toward the transition of nuclear energy that favours environmental sustainability.

Role of Scientific Reasoning in Elementary School Students' Construction of Food Pyramid Prediction Models (초등학생들의 먹이 피라미드 예측 모형 구성에서 과학적 추론의 역할)

  • Han, Moonhyun
    • Journal of Korean Elementary Science Education
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    • 제38권3호
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    • pp.375-386
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    • 2019
  • This study explores how elementary school students construct food pyramid prediction models using scientific reasoning. Thirty small groups of sixth-grade students in the Kyoungki province (n=138) participated in this study; each small group constructed a food pyramid prediction model based on scientific reasoning, utilizing prior knowledge on topics such as biotic and abiotic factors, food chains, food webs, and food pyramid concepts. To understand the scientific reasoning applied by the students during the modeling process, three forms of qualitative data were collected and analyzed: each small group's discourse, their representation, and the researcher's field notes. Based on this data, the researcher categorized the students' model patterns into three categories and identified how the students used scientific reasoning in their model patterns. The study found that the model patterns consisted of the population number variation model, the biological and abiotic factors change model, and the equilibrium model. In the population number variation model, students used phenomenon-based reasoning and relation-based reasoning to predict variations in the number of producers and consumers. In the biotic and abiotic factors change model, students used relation-based reasoning to predict the effects on producers and consumers as well as on decomposers and abiotic factors. In the equilibrium model, students predicted that "the food pyramid would reach equilibrium," using relation-based reasoning and model-based reasoning. This study demonstrates that elementary school students can systematically elaborate on complicated ecology concepts using scientific reasoning and modeling processes.

Newly-Diagnosed, Histologically-Confirmed Central Nervous System Tumours in a Regional Hospital in Hong Kong : An Epidemiological Study of a 21-Year Period

  • He, Zhexi;Wong, Sui-To;Yam, Kwong-Yui
    • Journal of Korean Neurosurgical Society
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    • 제63권1호
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    • pp.119-135
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    • 2020
  • Objective : To investigate the epidemiology of newly-diagnosed, histologically-confirmed (NDHC) central nervous system (CNS) tumours and its changes over a 21-year period in a regional hospital in Hong Kong. Methods : This is a single-institute retrospective descriptive study of patients undergoing surgery for CNS tumours in a regional hospital of Hong Kong in the period from January 1996 to December 2016. The histological definition of CNS tumours was according to the World Health Organization classification, while the site definition for case ascertainment of CNS tumours was as set out by the Central Brain Tumour Registry of the United States. Patients of any age, who had NDHC CNS tumours, either primary or secondary, were included. The following parameters of the patients were retrieved : age at diagnosis, gender, tumour location, and histological diagnosis. Population data were obtained from sources provided by the Government of Hong Kong. The incident rate, estimated by the annual number of cases per 100000 population, for each histology grouping was calculated. Statistical analyses, both including and excluding brain metastases, were performed. Statistical analysis was performed with Microsoft Excel, 2016 (Microsoft, Redmond, WA, USA). Results : Among the 2134 cases of NDHC CNS tumours, there were 1936 cases of intracranial tumours and 198 cases of spinal tumours. The annual number of cases per 100000 population of combined primary intracranial and spinal CNS tumours was 3.6 in 1996, and 11.1 in 2016. Comparing the 5-year average annual number of cases per 100000 population of primary CNS tumours from the period 1996-2000 to 2011-2015, there was an 88% increase, which represent an increase in the absolute number of cases by 4.52 cases/100000 population. This increase was mainly contributed by benign histologies. In the aforementioned periods, meningiomas increased by 1.45 cases/100000 population; schwannomas by 1.05 cases/100000 population, and pituitary adenomas by 0.91 cases/100000 population. While gliomas had a fluctuating 5-year average annual number of cases per 100000 population, it only had an absolute increase of 0.51 cases/100000 population between the 2 periods, which was mainly accounted for by the change in glioblastomas. Conclusion : This retrospective study of CNS tumour epidemiology revealed increasing trends in the incidences of several common CNS tumour histologies in Hong Kong, which agrees with the findings in large-scale studies in Korea and the United States. It is important for different geographic locations to establish their own CNS tumour registry with well-defined and structured data collection and analysis system to meet the international standards.

Analysis of Changes in the Population Potential of the Neighboring Areas of Sejong City Using the Accessibility Model (Accessibility 모델을 활용한 세종시 인접 지역의 인구잠재력 변화 분석)

  • Kim, Ho-Yong;Yun, Jeong-Mi
    • Journal of the Korean Association of Geographic Information Studies
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    • 제17권4호
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    • pp.167-178
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    • 2014
  • As large-scale housing sites are being developed rapidly in Sejong City, which was launched in 2012 for resolving the adverse effects of overconcentration in the capital area, promoting balanced development of the country, and reinforcing national competitiveness, changes in spatial structure are expected in the surrounding areas. For setting the directions of urban planning, it is essential to understand changes in spatial structure. This study purposed to measure changes in the spatial structure of neighboring areas resulting from the construction of Sejong City by approaching from the aspect of spatial interaction. In the analysis, we calculated population potential for future spatial interaction using the accessibility model, and interpreted quantitatively and qualitatively the outcomes of spatial interaction among neighboring areas before and after the construction of Sejong City using population potential as an indicator. According to the results of the analysis, the impact range of the population potential of the subject areas had been shrinking continuously since 1995, and in 2013 population potential dispersed as the population concentrated on and around Cheonan City. Although Sejong City, as a new area of population potential, was not found to play the role of a pivotal point for the surrounding areas, it is probably because the analysis was made just after people began to move to Sejong City. Accordingly, along with the effort of Sejong City to reach the planned population, it is necessary to keep monitoring changes in related factors and changes in the spatial structure of the surrounding cities resulting from the growth of population.

A Study on the Change of Regional Specialized Industries in Chungcheongbuk-do (충청북도의 지역별 특화 산업의 변화에 대한 연구)

  • Shin, Yeong-Jae
    • Journal of the Economic Geographical Society of Korea
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    • 제17권2호
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    • pp.349-365
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    • 2014
  • Chungcheongbuk-do can be said that it is not developed well because its surface accounts for 7.5% of Korea's whole land surface, and it accounts for 3.1% of population and main economical index from those of whole Korea. However, Chungcheongbuk-do should develop itself more by integrating of Cheongju-si and Cheongwon-gun, transfer of government facilities to Sejong city, and dispersing manufacturing companies of Seoul Metropolitan area. The factor which affects Chungcheongbuk-do's regional specialized industries is the distance from Cheongju-si and Gyeonggi-do. Service industries are specialized in urban area; manufacturing industries are specialized in regions which are close to Cheongju-si or Gyeonggi-do; and primary industries and consumer service industries are specialized in areas that is far from Cheongju-si. This study can be a foundation for studies on regional and industrial change of Chungcheongbuk-do by looking at its population and location quotient.

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Population Structure and Race Variation of the Rice Blast Fungus

  • Seogchan;Lee, Yong-Hwan
    • The Plant Pathology Journal
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    • 제16권1호
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    • pp.1-8
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    • 2000
  • Worldwide, rice blast, caused by Magnaporthe grisea (Hebert) Barr. (anamorph, Pyricularia grisea Sacc.), is one of the most economically devastating crop diseases. Management of rice blast through the breeding of blast-resistant varieties has had only limited xuccess due to the frequent breakdown of resistance under field conditions (Bonman etal., 1992; Correa-Victoria and Zeigler, 1991; Kiyosawa, 1982). The frequent variation of race in pathogen populations has been proposed as the principal mechanism involved in the loss of resistance (Ou, 1980). Although it is generally accepted that race change in M. grisea occurs in nature, the degree of its variability has been a controversial subject. A number of studies have reported the appearance of new races at extremely high rates (Giatgong and Frederiksen, 1968; Ou and Ayad, 1968; Ou et al., 1970; Ou et al., 1971). Various potential mechanisms, including heterokaryosis (Suzuki, 1965), parasexual recombination (Genovesi and Magill, 1976), and aneuploidy (Kameswar Row et al., 1985; Ou, 1980), have been proposed to explain frequent race changes. In contrast, other studies have shown that although race change could occur, its frequency was much lower than that predicted by earlier studies (Bonman et al., 1987; Latterell and Rossi, 1986; Marchetti et al., 1976). Although questions about the frequency of race changes in M. grisea remain unanswered, the application of molecular genetic tools to study the fungus, ranging from its genes controlling host specificity to its population sturctures and dynamics, have begun to provide new insights into the potential mechanisms underlying race variation. In this review we aim to provide an overview on (a) the molecular basis of host specificity of M. grisea, (b) the population structure and dynamics of rice pathogens, and (c) the nature and mechanisms of genetic changes underpinning virulence variation in M. grisea.

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Unmet Healthcare Needs Status and Trend of Korea in 2018 (2018 미충족의료율과 추이)

  • Joo, Jae Hong;Kim, Hwi Jun;Jang, Jieun;Park, Eun-Cheol;Jang, Sung-In
    • Health Policy and Management
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    • 제30권1호
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    • pp.120-125
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    • 2020
  • Unmet healthcare needs lead to increased disease severity, increased likelihood of complications, and worse disease prognosis. To examine the latest status of unmet healthcare needs in South Korea, the four different data configured with nationally representative sample of South Korean population were used: the Korea Health and Nutrition Examination Survey (KNAHANES, 2007-2018), the Community Health Survey (CHS, 2008-2018), the Korea Health Panel Survey (KHP, 2011-2016), and the Korean Welfare Panel Study (KOWEPS, 2006-2018). The proportion of individuals reporting unmet healthcare needs were 7.8% (KNHANES, 2018), 8.8% (CHS), and 10.8% (KHP, 2016). Annual percentage change which characterizes trend for the follow-up period was -9.1%, -3.2%, and -6.8%, respectively. The proportion of individuals reporting unmet healthcare needs due to cost were 1.2% (KNAHANES, 2018), 1.2% (CHS, 2018), 2.5% (KHP, 2016), and 0.5% (KOWEPS, 2018). Annual percentage change which characterizes trend for the follow-up period was -10.3%, -12.0%, -11.3%, and -18.8, respectively. The low-income population and the elderly population were vulnerable groups reporting the highest rate of unmet health care needs. The rate of unmet healthcare needs has been declining since the past decade, still, the disparity between different income groups and age groups suggests that there are many challenges to address.