• 한국시스템다이내믹스연구
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• 제15권3호
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• pp.37-59
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• 2014

This paper is to study dynamics of populations of religions. As human population is a crucial source of social dynamics, the religious population is a driving force that changes political and cultural landscape of society. Although many christian scholars have reported important causal factors in changing population of christian world, there are few studies on the dynamics of religious population in system dynamics. This paper interprets these dynamic mechanisms in terms of feedback loops and constructs a basic system dynamic model to forecast future trend of religious population in Korean society.

• 한국시스템다이내믹스연구
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• 제13권4호
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• pp.5-31
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• 2012

This paper aims at investigating the dynamics between aging population and local finance. In recent years, the aging rate has been accelerating the pace. The trend implies that Korea is moving towards the aging society, presumably, with unprecedented speed in the world. Aging society's biggest problems are centered around the explosive growth of the financial needs. In particular, these problems are apt to appear more seriously in local governments, as most of them are confronted with high level of aging population and poor financial bases. Firstly, it analyzes how the population structure in the local government impacts local finance, income and expenditure. Based upon in-depth literature reviews, this study examines variables related to aging population and local fiance. Secondly, it focuses on a series of positive and negative feedback loops which would reveal the essence of the mutual interaction structure between aging population and local governments' fiscal behaviors.

• Management Science and Financial Engineering
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• 제16권3호
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• pp.49-70
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• 2010

Customer population management models can be classified into three categories: the first category includes the models that analyze the customer population at cohort level; the second one deals with the customer population at aggregate level; the third one has interest in the interactions among the customer populations in the competitive market. Our study proposes a model that can analyze the dynamics of customer population in consumer-durables market at aggregate level. The dynamics of customer population includes the retention curves from the purchase or at a specific duration time, the duration time expectancy at a specific duration time, and customer population growth or decline including net replacement rate, intrinsic rate of increase, and the generation time of customer population. For this study, we adopt mathematical ecology models, redefine them, and restructure interdisciplinary models to analyze the dynamics of customer population at aggregate level. We use the data of previous research on dynamic customer population management at cohort level to compare its results with those of ours and to demonstrate the useful analytical effects which the precious research cannot provide for marketers.

• 한국시스템다이내믹스연구
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• 제12권2호
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• pp.95-126
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• 2011

This paper aims at developing a System Dynamics model with an augmented predator-prey interaction structure to deal with the population management of roe deer in Jeju, Korea. Although people still regard the creature as one of the important tourist attractions, there has been much debate on the issues of the appropriateness of the population size of roe deers because they have been stigmatized as crop damagers, and roadkill/poaching victims due to their natural habit to move around from the top mountain to the lowland of the island. The model is therefore to incorporate these migrating and grazing behaviors into an augmented Lotka-Volterra model coupling roe deer population in both parts of the island to that of predators and preys of the species. The authors also provide a comprehensive set of dynamic hypotheses and relevant CLD/SFD to understand the population dynamics of roe deer and co-evolving species and perform the steady-state analysis of the proposed equation system to verify the model behavior of the numerical example lastly presented in this paper.

• 한국시스템다이내믹스연구
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• 제17권1호
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• pp.107-134
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• 2016

Accelerated ageing with low fertility is one of the most critical problems in Korea. Because of ageing via low fertility, Korea will face a serious demographic cliff. This research primarily focus on the analyzing the dynamics of the marginal ageing state and decreasing population especially in Eup and Myeon region. This study based on the system dynamics approaches for finding causal loop structure of marginal ageing and critical mass of population disappearing. The results of this study are summarized as follows. First, demographic marginalization trends have already begun in the Eups and Myons of Gun. Second, marginal aging speed in Eup/Myeon areas is causing an population disappearing in the near future. Third, critical mass of population disappearing will begin when the rate of marginal aging is exceed 82% after 2023.

• 한국시스템다이내믹스연구
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• 제3권2호
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• pp.5-27
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• 2002

This paper evaluate and compare effectiveness of urban growth management measures in Korea using system dynamics model. Simple urban dynamics model was used to compare urban growth management measures. Since the late 1960s, Korean government has been implementing various urban growth management measures without much success. In the 1960s, factories, universities, and public agencies were strongly encouraged to move out to local areas. During the 1970s, regulations on greenbelt area was adopted to prevent urban sprawl. Besides, regulations to prevent location of population inducing facilities, and promoting dislocation of those facilities were implemented simultaneously. During the 1990, regulations on total number of factories in the metropolitan area, development fees were adopted. These various method of urban management were compared. Simulation results shows that promoting decentralization of population, preventing population immigration, expanding greenbelt area are effectiveness ones compared to controlling total number of population inducing facilities, and preventing construction of new industries. Some implications of the findings were discussed.

• 한국시스템다이내믹스연구
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• 제11권3호
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• pp.105-126
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• 2010

The ecology of house swallow is closely related to the humans life because their life depend on the human settlements conditions and environments. 30 years ago house swallows are very common at the country side, but recently they are very rare. Almost the number of house swallows decrease as 1 of hundredth during 20 years. Why this dramatic population decrease are happening in the ecology of house swallow? The Population size impacted by many factors such as nesting, breeding, feeding, returning. The objective of this paper is to analyse the population dynamics of the ecology of House Swallow. This paper focuses on the important ecological changes-nests, foods, and return rates from wintering area-associated with recent country side development. In this paper, we explore the feedback loops of population dynamics and simulate the policy scenario model.

• 한국환경농학회지
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• 제32권4호
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• pp.294-303
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• 2013

본 연구는 수학적 모델(Lotka-Volterra 방정식)을 이용하여 기후변화가 논습지를 이용하는 조류 개체군의 크기와 구조에 미치는 영향에 대해 분석 및 예측하였다. 특히 논습지를 이용하는 조류 개체군 동태에 영향을 주는 기후변화에 대해, 1) 계절 내 최고 및 최저 기온의 변화와 2) 계절 길이의 변화를 조합하여 11가지 가능한 기후변화시나리오를 모델시뮬레이션에 이용하였다. 본 연구의 수학모델은 기온 변화, 즉 계절이 바뀜에 따라 월동, 이동, 그리고 번식조류가 일정한 시기에 그리고 일정한 분포패턴으로 논습지를 취식 및 서식지로 이용하고 있음을 보였다. 기후변화 시나리오의 결과, 기온변화의 폭이 커질 수록 조류 개체군 동태의 변이는 증가하였으며, 계절의 길이 변화, 특히 계절이 짧아진 경우에 논습지를 이용하는 기간도 크게 짧아져 전체적으로 개체군 동태를 감소시켰다. 전체적으로 한 계절 내의 기온변화가 발생하고, 다른 계절은 평년 기온을 유지할 경우에는, 해당 계절의 조류 개체군 동태만 기온변화에 영향을 받았다. 더욱이 계절의 길이 변화는 계절 내 기온 변화보다 더 뚜렷한 개체군 동태의 변화를 유도하였다.

• ALGAE
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• 제18권4호
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• pp.295-299
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• 2003

The population dynamics of Ecklonia stolonifera was investigated at Tongyeong coastal area in the South Sea of Korea. The blade length and width, stipe length and diameter, mean total length and mean weight were measured from randomly collected fifty individuals in every month. The plants in Tongyeong population were relatively bigger than those of Busan Korea and Aomori Japan in terms of their blade length and width. The population biomass was low in winter and high in spring and summer. The sporangial sori were found from August to December but prominent in September and October. About 90 % of the Tongyeong population was consisted of one- and two-year old plants and the zoosporangial sori were observed mostly in two-year old plants. It was different from the results of Busan and Aomori population in which the zoosporangial sori were observed from the plants older than three years. The new populations were developed from the zoospores of two-year old plants and their generation time was relatively shorter than those of Busan and Aomori.

• 한국습지학회지
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• 제20권2호
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• pp.124-130
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• 2018

본 연구는 무인모니터링 시스템을 활용하여 논에 도래하는 조류의 현황과 개체군 변동 특성을 확인하기 위해 수행되었다. 무인모니터링 시스템을 이용한 조사와 전문가에 의한 현장 조사를 비교하여 개체군 변동 특성의 유사성을 파악하였고, 무인모니터링 시스템 조사를 통해 확인된 조류의 개체군 변동을 시공간적으로 평가하였다. 무인모니터링 시스템을 활용한 조사는 철원, 당진, 부안, 해남 4곳에서 2014년 1월 1일부터 2016년 12월 31일까지 06:00부터 20:00까지 14시간 동안 10분 단위로 촬영하였다. 전문가에 의한 현장 조사는 2016년 1월부터 12월까지 당진에서 월 1회 수행되었다. 무인모니터링 시스템을 활용하여 조사기간 동안 한 대의 무인모니터링 시스템에서 총 91,980장의 이미지를 획득하였다. 획득한 이미지 자료를 분석하여 백로류, 도요물떼새류, 오리기러기류의 동정 및 개체군 변동을 확인하였다. 무인모니터링 시스템과 현장 조사를 비교해보면 수조류 군집 변동 패턴이 현장 조사 결과와 유사한 것을 확인 할 수 있었다. 특히 백로류의 개체군 변동의 유사성이 가장 높게 나타났다. 무인모니터링 시스템을 이용하여 지역별 백로류의 개체군 변동 특성을 확인한 결과 지역에 따라 개체군 변동 특성이 다르게 나타나는 것을 확인할 수 있었다. 또한 무인모니터링 시스템은 월 단위, 일 단위, 분 단위와 같이 다양한 시간 스케일에서 개체군 변동 특성을 확인 할 수 있는 장점을 가지는 것으로 나타났다. 무인모니터링 시스템을 이용한 장기적인 자료 축적은 논습지를 활용하는 수조류 군집의 세부적인 장기변동 특성뿐만 아니라 미래 예측에도 유용하게 이용될 것으로 기대된다.