• Title/Summary/Keyword: Population changes

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The Effect of Disturbed Vision on Gait Parameters of the Young Healthy Population (혼란스러운 시각의 영향에 따른 보행요소들의 평가)

  • Kim Kyoung;Park Young-Han;Bae Sung-Soo
    • The Journal of Korean Physical Therapy
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    • v.12 no.1
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    • pp.41-47
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    • 2000
  • BACKGROUND AND PURPOSE. The purpose of this study is to investigate the effect of the disturbed vision on the gait distance parameters on the healthy young population. SUBJECTS. Twenty four healthy college aged individuals are randomly assigned to both a condition with a strobe light and the other condition without a strobe light. METHODS. The instrumentation used for gait analysis is the GaitRite electronic walkway system with a personal IBM computer. The examiner naked all the subjects to walk 6 times on the gait mat without the strobe light and. 6 times on the mat with the strobe light. The first 4 trials were practice and the last two trials were recorded in both conditions. The gait parameters analyzed were as follows : velocity, cadence, step length, and heel to heel base of support. RESULTS. Paired samples t-test used for this study did not found any significant differences between the two conditions because the p-values that were analyzed on the experiment were Utter than 0.05. The gait parameters that were analyzed included cadence, velocity, left and right heel to heel base of support, and left and right step length. DISCUSSION AND CONCLUSION. Based on this population, the condition of disturbed vision via the effect of the strobe light was not significantly challenging to compromise the body's sensory systems. However, in the elderly population, these systems can undergo age related changes. Visual changes rapidly decline in people 60 to 80 years of age and changes in the vestibular system include $20-40\%$ reduction in hair cells.

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A Study on the Effect of Administrative Districts Separation to the Changes of Population and Industry in a Region: A Case Study on Goesan-gun and Jeungpyeong-gun, Chungcheongbuk-Do (행정구역 분리가 지역의 인구와 산업 변화에 미친 영향에 대한 연구: 충청북도 괴산군과 증평군을 사례로)

  • Shin, Yeong-Jae
    • Journal of the Korean Geographical Society
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    • v.51 no.3
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    • pp.381-399
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    • 2016
  • Goesan-gun and Jeungpyeong-gun, Chungcheongbuk-Do have been separated administratively since 2003. Goesan-gun is rural area, and Jeungpyeong-gun is urban area. The purpose of this study is to observe changes after the separation of administrative districts (Goesan-gun and Jeungpyeong-gun, Chungcheongbuk-Do). This study observed changes of Goesan-gun and Jenugpyeong-gun, Chungcheongbuk-Do based on population, the highest land value, employees and location quotient. Population of Goesan-gun has decreased, and that of Jeungpyeong-gun has increased. The highest land value of Jeungpyeong-gun has increased more than that of Goesan-gun. Observation of location quotient, with the location quotient of 2013 as a criterion, showed that manufacturing business and producer service business have developed in Jeungpyeong-gun, while agriculture and customer service business have developed in Goesan-gun. This result is due to the difference between regional characteristic of Goesan-gun and Jeungpyeong-gun.

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A Case Study on the Emission Impact of Land Use Changes using Activity-BAsed Traveler Analyzer (ABATA) System (활동기반 통행자분석시스템(ABATA)을 이용한 토지이용변화에 따른 차량 배기가스 배출영향 사례 분석)

  • Eom, Jin Ki;Lee, Kwang-Sub
    • Journal of Cadastre & Land InformatiX
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    • v.53 no.1
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    • pp.21-36
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    • 2023
  • Activity-based modeling systems have increasingly been developed to address the limitations of widely used traditional four-step transportation demand forecasting models. Accordingly, this paper introduces the Activity-BAsed Traveler Analyzer (ABATA) system. This system consists of multiple components, including an hourly total population estimator, activity profile constructor, hourly activity population estimator, spatial activity population estimator, and origin/destination estimator. To demonstrate the proposed system, the emission impact of land use changes in the 5-1 block Sejong smart city is evaluated as a case study. The results indicate that the land use with the scenario of work facility dispersed plan produced more emissions than the scenario of work facility centralized plan due to the longer travel distance. The proposed ABATA system is expected to provide a valuable tool for simulating the impacts of future changes in population, activity schedules, and land use on activity populations and travel demands.

Prediction of the Real Estate Market by Region Reflecting the Changes in the Number of Houses and Population (주택수와 인구증가 변화를 반영한 지역별 부동산 시장 예측)

  • Bae, Young-Min
    • Journal of the Korea Convergence Society
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    • v.12 no.4
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    • pp.229-236
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    • 2021
  • There has been a lot of research on the real estate market, but a lack of research on the supply and demand of housing supply in each region, reflecting the changes in population growth and supply. It is calculated as the transition probability of the Markov chain model by reflecting the data on the number of houses per 1,000 people in the past 35 years and the forecast data for population change by region, in terms of supply (housing) to demand (population) for factors on the real estate market. According to the calculation results of the real estate market by region, the housing supply to the metropolitan area such as Gyeong-gi, Incheon, and Seoul is expected to be insufficient for a considerable period of time, considering the population changes by region. To stabilize the real estate market, it was confirmed that it was necessary to actively apply the differentiation of housing supply by region. It is meaningful in terms of verifying long term trends in the real estate market by region that reflect the prediction of population change, and it is expected that the methods used in this study will be practical through the analysis results using the historical data.

Population dynamics of the red-eared slider (Trachemys scripta elegans) with changes in the population dependent carrying capacity in Republic of Korea

  • Wi, Yunju;Oh, Gyujin;Kang, Hee-Jin;Sung, Ha-Cheol;Cheon, Seung-ju;Jin, Hong-Sung
    • Journal of Ecology and Environment
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    • v.46 no.1
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    • pp.1-7
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    • 2022
  • Background: In this study, we proposed that the population dynamics of non-native red-eared sliders (Trachemys scripta elegans) depends on the species' habitat extension and survivorship. We used a logistic equation with time-dependent habitat carrying capacity. In detail, the present carrying capacity depends on the red-eared slider population of the previous year. Anthropogenic activities such as the abandonment of previously captive red-eared sliders or the release due to religion customs would supply new habitats to the species. Therefore we assumed that anthropogenic spread increases the habitat carrying capacity. Based on the urbanization increase rate of 3% in Korea from 1980 to 2000, we assumed an annual spread of 3% to simulate the population dynamics of the red-eared slider. In addition, the effect on the population of an increase of natural habitats due to migration was simulated. Results: The close relationship between the distributions of non-native red-eared sliders and of urbanized areas demonstrates that urbanization plays an important role in providing new habitats for released individuals. Depending on the survivorship, the population of the red-eared slider in Korea increased 1.826 to 3.577 times between 1980 and 2000. To control population growth, it is necessary to reduce carrying capacity by reducing habitat expansion through prohibition of release into the wild ecosystem and careful managements of the wetland or artificial ponds. Changes in the habitat carrying capacity showed that the population fluctuated every other year. However, after several years, it converged to a consistent value which depended on the survivorship. Further, our results showed that if red-eared sliders expand their habitat by natural migration, their population can increase to a greater number than when they have a 99% survivorship in a fixed habitat. Conclusions: Further introductions of red-eared sliders into wetlands or artificial ponds should be prohibited and managed to prevent future spread of the species. Moreover, it is important to reduce the species' survivorship by restoring disturbed ecosystems and maintaining healthy ecosystems.

Vertical Distribution of Tiger Worm (Oligochaeta : Eisenia fetida) Population in the Rearing Bed (지렁이 사육상에서 줄지렁이(Eisenia fetida) 개체군의 수직분포)

  • Park, Kwang-Il;Kim, Byung-Woo;Bae, Yoon-Hwan
    • Journal of the Korea Organic Resources Recycling Association
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    • v.15 no.4
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    • pp.93-99
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    • 2007
  • Vertical distribution of tiger worm(Eisenia fetida) population in the earthworm rearing bed was investigated with feeding paper mill sludge. More than 50% of larva and adult population of Eisenia fetida lived within the depth of 5 cm from the surface of rearing bed. And more than 96% of the population of larva, adult and cocoon lived within the depth of 20 cm. Percental vertical distribution of Eisenia fetida population in the rearing bed was not much influenced by the changes in the height of rearing bed or density of earthworm population.

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Population Density Changes of Bacteria and Soybean Sprout Rotting Bacteria on Soybean Leaves (콩 잎에 서식하는 세균 및 콩나물 부패균의 밀도 변화)

  • 최재을;이은정;신철우
    • Korean Journal of Plant Resources
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    • v.12 no.2
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    • pp.152-160
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    • 1999
  • Bacterial population density on soybean leaves was $10^2~10^5CFU/cm^2$. Bacterial population density was increased by progress of plant growth stage. Population density of soybean sprout rotting bacteria on soybean leaves was $0~10^3CFU/cm^2$. Population density of soybean sprouts rotting bacteria was related to cultivating area, but not related to plant growth stage. Cultivar and population density of soybean sprout rotting bacteria were less corelated, and varied by plant growth stages and plant parts. Erwina cypripedii, E. carotovora subsp. carotovora, Xanthomonas campestris pv. glycines, Staphylococcus sp., and Micrococcus sp. were identified as pathogenic bacteria causing soybean sprout rot. In generally population density of E. cypripedii, E. carotovora subsp. carotovora, Micrococcus sp., and X. campestris pv. glycines were high.

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A Study on the Change of the Urban Heat Island Structure in Busan Metropolitan Area, Korea (부산지역의 도시열섬 구조 변화에 관한 연구)

  • Kim, Hyunsu;Seok, Hyun-Bae;Kim, Yoo-Keun
    • Journal of Environmental Science International
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    • v.23 no.11
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    • pp.1807-1820
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    • 2014
  • The spatial and temporal changes of the annual mean urban heat island(UHI) intensity were investigated using near surface temperature data measured at 16 automatic weather systems(AWS) in Busan metropolitan area(BMA) during the 11-yr period, from 2000 to 2010. For nighttime, the annual mean UHI intensity at Dongnae(U1) in 2000 was weaker than it in 2010. However the change of the annual mean UHI intensity at Daeyeon(U2) during 11 years was different from it at U1. The annual frequency of the UHI intensity over $5^{\circ}C$ considerably increased at U2 and decreased at U1 during 11 years. The center of the UHI also spatially shifted southward with Daeyeon and Haeundae in BMA. It would be caused by the increase of urban area, population-density and transportation near U2 and by the decrease of them near U1. We found that the spatial and temporal differences of the UHI intensity have coincided with changes of land-use, population density and transportation in BMA.

Aging-related Changes of the Mechanical Properties of the Erector Spinae Muscles in Young and Elderly Men (청년과 노인 남성 척주세움근의 노화에 따른 물리적 성질 변화)

  • Lee, Na-Kyung
    • Journal of The Korean Society of Integrative Medicine
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    • v.9 no.4
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    • pp.39-47
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    • 2021
  • Purpose : This study aimed to investigate age-related mechanical changes in the erector spinae muscles, specifically in terms of tone, elasticity, and stiffness, in the elderly population compared to the younger population Methods : The mechanical properties, including tone, elasticity, and stiffness, of the erector spinae muscles were measured using myotonometry in 47 male adult subjects, divided into the younger group (23 subjects aged 19 to 28 years) and the elderly group (22 subjects aged 69 to 83 years). The measurements were performed in both the prone and sitting positions. The tone, elasticity, and stiffness of the erector spinae muscles were statistically compared between the two groups using a t-test. Results : The study showed increased stiffness and decreased elasticity in the erector spinae muscles in the elderly group compared to the younger group (p<0.01~0.001). The results were similar in both the prone and sitting positions. Conclusion : There are age-related degenerative changes that affect the mechanical properties of the erector spinae muscles. In addition, myotonometry can be suggested to be a useful examination tool in evaluating these changes provided that further studies are conducted and standard methods of application have been established in the future.

The Decrease of Korean Population and the Changes of Regional Characteristics in Rural Area of Yanbian Korean Autonomous Prefecture (중국 연변 농촌지역의 조선족인구 감소와 지역성 변화 - 두만강변 조선족 농촌 마을을 중심으로 -)

  • Lu, Bi Shun
    • Journal of the Korean association of regional geographers
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    • v.19 no.4
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    • pp.668-682
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    • 2013
  • This study illustrates the mechanism of The Decrease of Korean population in Yanbian Korean Autonomous Prefecture (YBKAP) and some changes of regional characteristics since China's economic reforming. Due to China's Implementing market economic system, deregulating in family register system, higher mobility since establishing Sino-Korean diplomatic relations, the expansion of intermarriages and residential areas, Korean community is confronted with lower birthrate and continuous mobility of the young and women. It directly connects to a decrease in urban population and aging, causing a decline in farming production, disintegrating of Korean community, weakening the function of villagers' organization, shrinking in Korean education and leaderships. For supplementing the shorted labor, Chinese farmers from other areas flow into the YBKAP, showing some different trends, such as farming Chinesization, Chinese farmers' higher economic level than Korean, the Korean traditional paddy field transforming into dry farmland with single-crop farming and pursuing commercial production in labor management. At the moment, declining population in Korean community in rural areas means that the community could not respond the changes of farming environments appropriately and in some way it is facing with the crisis of die away from the Chinese society. It needs an unconventional support and development policies in YBKAP rural areas.

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