• Title/Summary/Keyword: population change

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Characteristics of Red Tide Blooms in the Lower reaches of Taehwa River (태화강 하류의 적조발생 특성)

  • Cho, Hong-Je;Yoon, Yeong-Bae;Kang, Ho-Seon;Yoon, Sung-Kyu
    • Journal of Korean Society of Water and Wastewater
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    • v.25 no.4
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    • pp.453-462
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    • 2011
  • This study was analyzed to determine the cause of red tide at 10 and 30 days antecedental rainfall, stage and discharge in the Taehwa River, tidal data of Ulsan port, also, it was analyzed variation of red tide population, salinity, BOD, COD, T-N, T-P at S1, S2 each point. Most of the red tide in the Taehwa River occurred by provision of proper nutrients with antecedent, the proximity between discharge and low-flow capacity, and stage and discharge of stabilized condition after the sea water was inflowed by maximum tide difference. Red tide population is not nearly related to the change of salinity, the Taehwa River seems specific features of Non-coastal rivers downstream, because red tide was occurred when salinity quite low-end condition.

Applying Steady State Analysis to the Study of Mitten Crabs in Jichun, Kum River (동적 균형상태를 중심으로 본 금강 지천의 참게자원 분석)

  • Jeon, Dae-Uk;Jeong, Hoi-Seong
    • Korean System Dynamics Review
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    • v.11 no.1
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    • pp.27-57
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    • 2010
  • This article deals with an ecological-economic analysis of the 'Pasture Project of Kum River', which is the farming plan of mitten crabs using Jichun, a stream of the River Kum where the natural propagation of mitten crabs are blocked because of the estuary dam constructed in 1990. Toward analyzing the ecological and economic effects of the crab releasing and harvesting activities in Jichun, a two-stage cohort model of population dynamics with cannibalistic behaviors and density restrictions in biomathematics is adopted, despite of the current infertility in Kum, considering the opportunity of establishing dam fishways in the near future. This study moreover presents a method of parameter estimation especially with assuming a steady state of the ecosystem, and performs various analyses such as the risk measurement of climate change and the economic value of such fishways.

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Alcohol Consumption and Alcohol-involved Traffic Accident (알코올 소비와 음주교통사고)

  • 이원재
    • Korean Journal of Health Education and Promotion
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    • v.14 no.2
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    • pp.69-94
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    • 1997
  • Recently, occurrence of alcohol-involved traffic accidents is increasing while all the accidents by violation of law except drunk driving. Traffic accidents by drunk driving has a great external cost. In detecting drunk driving, blood alcohol content Many studies reported close correlation between blood alcohol content and traffic accidents by drunk driving. The risk of traffic accidnet increases exponentially as blood alcohol content increases. To control traffic accidents by drunk driving, decide target population. Heavy drinkers are few and responsible for a small part of the loss while casual drinkers are many and responsible for a large part of the loss. Casual drinkers need to be included in the targer population for the control of traffic accident by drunk driving. Stragegies to reduce the quantity of alcohol consumed, change the pattern of drink, such as frequency of drinking, raise of perceived risk of accident need to be sought.

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Technological Trend of Crystallization Research for Bioproduct Separation (Bioproduct 분리를 위한 결정화 연구 동향)

  • Kim, Woo-Sik;Lee, Eun-Kyu
    • KSBB Journal
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    • v.20 no.3
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    • pp.164-176
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    • 2005
  • In bioengineering field, current academic trends and informations on crystallization technology for bioproduct separation were summarized. It is essential for utilizing the crystallization technology to understand the fundamental phenomena of crystallization of crystal nucleation, crystal growth, crystal agglomeration and population balance for the design of crystallizers. In general, the crystal nucleation that the crystalline solids occur from the solution is analyzed by Gibb's free energy change in the aspect of thermodynamics and in the present paper the crystal nucleation models based on the above thermodynamics are summarized by their key characteristics. The crystal growth and agglomeration, which have been studied over 50 years and are essential phenomena for separation technology, are reviewed from their basic concept to most leading edge trend of researches. In the material and population balances for the designs of crystallization separation process, the analysis of crystallizers is summarized. Thereon, the present review paper will academically contribute the understanding the crystallization phenomena and the design of the crystallization separation process.

Regional Decline and Sociodemographic Change in Kangwon Southern-Belt Mine Area (강원남부 탄광지역의 쇠퇴와 인구사회학적 변화)

  • Chung, Sung-Ho
    • Korea journal of population studies
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    • v.27 no.2
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    • pp.205-229
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    • 2004
  • 이 글은 강원남부 탄광지역의 쇠퇴와 인구사회학적 변동 양상을 검토하는데 그 목적이 있다. 이를 위해 우선 탄광지역의 특성을 살펴보고 탄광지역이 쇠퇴하게 된 원인을 규명하고자 한다. 그 다음으로 지역사회에 나타나고 있는 산업구조와 인구구조의 변화를 중점적으로 살피고자 한다. 연구 결과 태백지역이 쇠퇴하게 된 직접적인 요인은 석탄산업 합리화 정책의 시행으로 볼 수 있다. 이와 함께 태백지역은 탄광산업이 지역성장이 유일한 원동력이었다는 사실 즉, 탄광산업의 쇠퇴는 바로 이 지역의 급격한 경기침체와 인구유출의 직접적인 원인이 되었음을 알 수 있다. 급격한 경기침체는 산업구조의 변화에서 잘 드러나고 있으며 인구유출 양상은 지역의 인구변화 추이에서 잘 드러나고 있다. 최근 폐광지역개발지원특별법에 의해 수립된 종합개발계획도 상당 부분 무산되거나 기약 없이 미뤄지고 있다는 점과 지역개발을 강원랜드 카지노에만 지나치게 의존하고 있는 문제점 등이 드러나면서 지역경기 침체와 인구감소 추세는 계속되고 있다. 탄광지역의 주민소득 증대는 물론 새로운 고용창출로 지역경제를 활성화시키는 보다 구체적이고 실질적인 발전 전략이 필요하다.

The Welfare Equipments on the View of Handicapped People's Living Environment (障害者の住宅環境から見た福祉機器)

  • Yoshinori, Kanazawa;Lee, Sang-Un
    • Physical Therapy Korea
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    • v.7 no.4
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    • pp.65-71
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    • 2000
  • Recently, we can see worldwide the rapid increase in the population of the aged people, while that of young people is decreasing. Especially present Japan has a super-aged society, and it is a big social problem how to take effective measures to that in the future, Some items as well as researches have come out of various research them to the user. Such a change in population will be seen also in South Korea. Because South Korea has many social things in common with Japan, though they have different languages. Through this report, it is expected that it will be a good example for Japan PT to expand its activities and will connect to the future joint research of South Korea and Japan, by introducing it to South Korea.

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The Logic of Vertical Density: Tall Buildings in the 21st Century City

  • Al-Kodmany, Kheir
    • International Journal of High-Rise Buildings
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    • v.1 no.2
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    • pp.131-148
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    • 2012
  • This paper attempts to summarize recent debates on tall buildings. It first explains the driving forces of constructing tall buildings including population increase, rural-to-urban migration, demographic change, agglomeration, and human aspiration. Next, it discusses disadvantages and challenging factors that are frequently raised in making a case against tall buildings including economics, environmental factors, historic context, public safety, and psychological issues. The paper concludes by affirming that tall buildings will persist in the $21^{st}$ century due to strong commitment to urban sustainability and significant population increase worldwide.

Discrete optimal sizing of truss using adaptive directional differential evolution

  • Pham, Anh H.
    • Advances in Computational Design
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    • v.1 no.3
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    • pp.275-296
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    • 2016
  • This article presents an adaptive directional differential evolution (ADDE) algorithm and its application in solving discrete sizing truss optimization problems. The algorithm is featured by a new self-adaptation approach and a simple directional strategy. In the adaptation approach, the mutation operator is adjusted in accordance with the change of population diversity, which can well balance between global exploration and local exploitation as well as locate the promising solutions. The directional strategy is based on the order relation between two difference solutions chosen for mutation and can bias the search direction for increasing the possibility of finding improved solutions. In addition, a new scaling factor is introduced as a vector of uniform random variables to maintain the diversity without crossover operation. Numerical results show that the optimal solutions of ADDE are as good as or better than those from some modern metaheuristics in the literature, while ADDE often uses fewer structural analyses.

Improving the Workplace Experience of Caregiver-Employees: A Time-Series Analysis of a Workplace Intervention

  • Ding, Regina;Dardas, Anastassios;Wang, Li;Williams, Allison
    • Safety and Health at Work
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    • v.12 no.3
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    • pp.296-303
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    • 2021
  • Background: Rapid population aging in developed countries has resulted in the working-age population increasingly being tasked with the provision of informal care. Methods: An educational intervention was delivered to 21 carer-employees employed at a Canadian University. Work role function, job security, schedule control, work-family conflict, familywork conflict, and supervisor and coworker support were measured as part of an aggregated workplace experience score. This score was used to measure changes pre/post intervention and at a follow-up period approximately 12 months post intervention. Three random intercept models were created via linear mixed modeling to illustrate changes in participants' workplace experience across time. Results: All three models reported statistically significant random and fixed effects intercepts, with a positive coefficient of change. Conclusion: This suggests that the intervention demonstrated an improvement of the workplace experience score for participants over time, with the association particularly strong immediately after intervention.

A Diagnosis of Shrinking City Using Population Gradient Curve: A Case Study on the City of Yeong-ju (인구밀도경사함수를 이용한 도시축소현상 진단 - 영주시를 사례로 -)

  • Kim, Min-Seok;Byun, Tae-Geun;Lee, Sang-Ho
    • Journal of the Korean Regional Science Association
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    • v.35 no.4
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    • pp.33-45
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    • 2019
  • Due to the global low growth trend, urban shrinkage is a major issue of urban policy in major industrialized countries. According to the research results of the KRIHS(Korea Research Institute for Human Settlements, 2016), 23 out of 77 cities in Korea were diagnosed as continuous or temporary shrinking cities. However, the criterion for diagnosing shrinking cities remain on the simple demographic side, and the spatial shrinkage pattern of the city is not considered. Therefore, this study diagnosed urban shrinkage phenomenon considering the characteristics of Yeong-ju, a poly-centric city, by using the population gradient curve, which is one of the urban spatial structure analysis methods. As a result of the diagnosis, Yeong-ju turned out to be a shrinking city with the population density and the slope of population density increasing. In the case of area of Dong, a sprawl phenomenon in which the population density of the CBD and the slope of the population density were decreased was shown. And in the case of Punggi-eup, a simple shrinkage phenomenon in which only the population density of the CBD was decreased was shown. The results show that even within a city, the pattern of spatial change can be different for each centers. In the case of a city with a poly-centric structure, the implications for the individual diagnosis of not only the entire city but also the detailed area were drawn.