• Title/Summary/Keyword: Population dynamics

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On the Study of Developement for Urban Meteorological Service Technology (도시기상서비스 기술 개발에 관한 연구)

  • Choi, Young-Jean;Kim, Chang-Mo;Ryu, Chan-Su
    • Journal of Integrative Natural Science
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    • v.4 no.2
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    • pp.149-157
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    • 2011
  • Urbanization of the world's population has given rise to more than 450 cities around the world with populations in excess of 1 million (megacity) and more than 25 so-called metacities with populations over 10 million (Brinkhoff, 2010). The United States today has a total resident population of more than 308,500,000 people, with 81 percent residing in cities and suburbs as of mid - 2005 (UN, 2008). Urban meteorology is the study of the physics, dynamics, and chemistry of the interactions of Earth's atmosphere and the urban built environment, and the provision of meteorological services to the populations and institutions of metropolitan areas. While the details of such services are dependent on the location and the synoptic climatology of each city, there are common themes, such as enhancing quality of life and responding to emergencies. Experience elsewhere (e.g., Shanghai, Helsinki, Tokyo, Seoul, etc.) shows urban meteorological support is a key part of an integrated or multi-hazard warning system that considers the full range of environmental challenges and provides a unified response from municipal leaders. Urban meteorology has come to require much more than observing and forecasting the weather of our cities and metropolitan areas. Forecast improvement as a function of more and better observations of various kinds and as a function of model resolution, larger ensembles, predicted probability distributions; Responses of emergency managers, government officials, and users to improved and probabilistic forecasts; Benefits of improved forecasts in reduction of loss of life, property damage, and other adverse effects. A national initiative to enhance urban meteorological services is a high-priority need for a wide variety of stakeholders, including the general, commerce and industry, and all levels of government. Some of the activities of such an initiative include: conducting basic research and development; prototyping and other activities to enable very--short and short range predictions; supporting and improving productivity and efficiency in commercial and industrial sectors; and urban planning for long term sustainability. In addition urban test-beds are an effective means for developing, testing, and fostering the necessary basic and applied meteorological and socioeconomic research, and transitioning research findings to operations. An extended, multi-year period of continuous effort, punctuated with intensive observing and forecasting periods, is envisioned.

Parent-Child Difference in Attitudes, Resources, and Constraints, and the Impacts of these Factors on Generational Proximity in the United States and Japan (노인 부모와 자녀 사이의 지리적 근접성에 대한 연구 : 미국과 일본의 사례를 중심으로)

  • 박경숙
    • Korea journal of population studies
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    • v.20 no.2
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    • pp.67-98
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    • 1997
  • This study examines multi-level factors geographic proximities between elderly parents and their children in the United States and Japan. Despite their similar economies, the United States and Japan show a significant difference in their patterns of generational proximity. In 1993, half of US non-Hisapnic white parents aged 70 or over lived separately but within 10 miles of their nearest children and a majority of them lived far from their non-nearest children. The family geographic network for Japanese elderly parents is more hierarchial. In 1989, 74 percent of Japanese parents aged 70 and over lived with their nearest children but most of them lived far from their non-nearest children. To explain this distinctive pattern of inter- and intra-family differences in generational proximities in the two societies, this study employs a multi-level analysis which compares the relative importance of life course conditions of elderly parents and their children and economic and ecological characteristics of elderly parent's places of residence in influencing generational proximities.

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Structure and Dynamics of Taxus cuspidata Populations (주목(Taxus cuspidata) 개체군의 구조와 동태)

  • Chun, Young-Moon;Hong, Moon-Pyo;Lee, Na-Yeon;Seo, Eun-Kyoung;Lee, Seung-Ho
    • Korean Journal of Plant Resources
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    • v.25 no.1
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    • pp.123-131
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    • 2012
  • This study analyzed on the characteristics of community structure, species composition, population conditions and annual mean radial growth of Taxus cuspidata in the subalpine zone of the Seoraksan, Deokyusan, and Hallasan National Parks. Deokyusan and Hallasan sites had three layers of stratification structure without tree layer in it and four layer in Seoraksan site. The major dominant species in the order of importance value were as follows: T. cuspidata, Acer tschonoskii var. rubripes, Quercus mongolica, Abies koreana and Sorbus commixta. The trees (> 5 cm DBH) of T. cuspidata were extremely high with 986.0 individuals/ha at the Hallasan site. Average DBH class were 42.0 cm at the Hallasan site and mainly showed large class. The populations of seedlings and saplings with 357.3 individuals/ha, and juvenile with 128.6 individuals/ha, as a succession tree, were found to be the highest at the Hallasan site. In the size frequency distribution, the populations of T. cuspidata in Mt. Halla site showed a reverse J-shaped curve and it was estimated that T. cuspidata community of this site might be maintained continuously as a stable state like present state. Annual mean radial growth of T. cuspidata populations at Seoraksan, Deokyusan, and Hallasan sites showed up as 1.27 mm/year, 0.93 mm/year and 0.89 mm/year respectively.

Effects of Temperature on the Development and Reproduction of Matsumuraeses falcana (Lepidoptera: Tortricidae) (어리팥나방(Matsumuraeses falcana)의 발육과 생식에 미치는 온도의 영향)

  • Jeong Joon, Ahn;Eun Young, Kim;Bo Yoon, Seo; Jin Kyo, Jung
    • Korean journal of applied entomology
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    • v.61 no.3
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    • pp.435-447
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    • 2022
  • The soybean podborer, Matsumuraeses falcana (Lepidoptera: Tortricidae), is one of important pests in soybean crop. In the purpose of forecasting population dynamics of M. falcana, we investigated the effects of temperature on development of each life stage, adult longevity and fecundity of Matsumuraeses falcana at seven constant temperatures of 10, 13, 19, 22, 25, 28, and 31℃. Eggs hatched successfully at all temperature subjected. M. falcana developed from egg hatching to adult emergence at the tested temperatures except 10, 13, and 31℃. The developmental period of each life stage and adult longevity of M. falcana decreased as temperature increased. The lower developmental threshold (LDT) and thermal constant (K) from egg hatching to adult emergence of M. falcana were estimated by linear regression as 10.2℃ and 492.04DD, respectively. Lower and higher threshold temperature (TL and TH) were calculated by the Lobry-Rosso-Flandrois (LRF) and Sharpe-Schoolfield-Ikemoto (SSI) models. TL and TH from egg hatching to adult emergence using SSI model were 16.7℃ and 29.1℃. Thermal windows, i.e., the range in temperature between the minimum and maximum rate of development, of M. falcana was 12.4℃. We constructed the adult oviposition model of M. falcana using adult survivorship and fecundity. Temperature-dependent immature development and adult oviposition models will help constructing the population model of M. falcana and developing the strategies of integrated pest management in soybean fields.

The effect of external influence and operational management level on urban water system from water-energy nexus perspective (물-에너지 넥서스 관점에서 외부영향과 운영관리 수준이 도시물순환시스템에 미치는 영향)

  • Choi, Seo Hyung;Shin, Bongwoo;Song, Youngseok;Kim, Dongkyun;Shin, Eunher
    • Journal of Korea Water Resources Association
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    • v.56 no.9
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    • pp.587-602
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    • 2023
  • Due to climate change, population growth, and economic development, the demand for water in the urban water system (UWS) and the energy required for water use constantly increase. Therefore, beyond the traditional method of considering only the water sector, the Nexus approach, which considers synergies and trade-offs between the water and energy sectors, has begun to draw attention. In previous researches, the Nexus methodology was used to demonstrate that the UWS is an energy-intensive system, analyze the water-energy efficiency relationship surrogated by energy intensity, and identify climate (long-term climate change, drought, type), geographic characteristics (topography, flat ratio, location), system characteristics (total supply water amount, population density, pipeline length), and operational management level (water network pressure, leakage rate, water saving) effects on the UWS. Through this, it was possible to suggest the direction of policies and institutions to UWS managers. However, there was a limit to establishing and implementing specific action plans. This study built the energy intensity matrix of the UWS, quantified the impact of city conditions, external influences, and operational management levels on the UWS using the water-energy Nexus model, and introduced water-energy efficiency criteria. With this, UWS managers will be able to derive strategies and action plans for efficient operation management of the UWS and evaluate suitability and validity after implementation.

Parameterization of the Temperature-Dependent Development of Panonychus citri (McGregor) (Acari: Tetranychidae) and a Matrix Model for Population Projection (귤응애 온도발육 매개변수 추정 및 개체군 추정 행렬모형)

  • Yang, Jin-Young;Choi, Kyung-San;Kim, Dong-Soon
    • Korean journal of applied entomology
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    • v.50 no.3
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    • pp.235-245
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    • 2011
  • Temperature-related parameters of Panonychus citri (McGregor) (Acarina: Tetranychidae) development were estimated and a stage-structured matrix model was developed. The lower threshold temperatures were estimated as $8.4^{\circ}C$ for eggs, $9.9^{\circ}C$ for larvae, $9.2^{\circ}C$ for protonymphs, and $10.9^{\circ}C$ for deutonymphs. Thermal constants were 113.6, 29.1, 29.8, and 33.4 degree days for eggs, larvae, protonymphs, and deutonymphs, respectively. Non-linear development models were established for each stage of P. citri. In addition, temperature-dependent total fecundity, age-specific oviposition rate, and age-specific survival rate models were developed for the construction of an oviposition model. P. citri age was categorized into five stages to construct a matrix model: eggs, larvae, protonymphs, deutonymphs and adults. For the elements in the projection matrix, transition probabilities from an age class to the next age class or the probabilities of remaining in an age class were obtained from development rate function of each stage (age classes). Also, the fecundity coefficients of adult population were expressed as the products of adult longevity completion rate (1/longevity) by temperature-dependent total fecundity. To evaluate the predictability of the matrix model, model outputs were compared with actual field data in a cool early season and hot mid to late season in 2004. The model outputs closely matched the actual field patterns within 30 d after the model was run in both the early and mid to late seasons. Therefore, the developed matrix model can be used to estimate the population density of P. citri for a period of 30 d in citrus orchards.

Korean and Worldwide Research Trends on Rare Plant and Endemic Plant in Korea (한국의 희귀 및 특산식물에 대한 국내·외 연구동향)

  • Chae, Hyun-Hee;Kim, Young-Chul;Son, Sung-Won
    • Korean Journal of Environment and Ecology
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    • v.36 no.3
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    • pp.257-276
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    • 2022
  • Studies on rare and endemic plant conservation should be performed nationally to conserve plant diversity. Studies targeting a specific taxon have been reported based on the necessity of conserving plant diversity. From this point of view, there is an increasing necessity to compare and evaluate the studies for conservation. Moreover, it is necessary to analyze and review the direction for study subjects and items required for effective conservation of rare and endemic plants in Korea, based on the analysis results of collected data. We analyzed trends of studies on rare and endemic plants worldwide. In particular, we collected and analyzed the study trend in Korea. Study fields of the rare and endemic plants were divided into six classifications, of which the conservation ecology classification was sub-divided into the species traits, population study, and biological interaction. We have collected conservation ecology studies showing significant differences in regions and countries. They have been actively conducted in Europe and North America by region and in Japan and the United States by country. On the contrary, studies on basic ecology accounted for the most, followed by conservation genetics and restoration ecology in Korea. It was revealed that the portion of conservation ecology conducted in Korea was lower than that of the world. Moreover, studies mainly focused on a specific taxon of rare and endemic plants, such as endangered plants designated by the Korean Ministry of Environment. Particularly in Korea, conservation genetics and restoration ecology studies accounted for high percentages. Considering the worldwide study trends, particularly those in Europe and North America that lead the study of conservation ecology, we suggest approaches to increase the percentages of conservation ecology, including securing the information on species traits, population structure and population dynamics, and interaction between animals and plants are necessary for effective conservation of rare and endemic plants in Korea.

Monitoring Bacterial Population Dynamics Using Real-Time PCR During the Bioremediation of Crude-Oil-Contaminated Soil

  • Baek, Kyung-Hwa;Yoon, Byung-Dae;Cho, Dae-Hyun;Kim, Byung-Hyuk;Oh, Hee-Mock;Kim, Hee-Sik
    • Journal of Microbiology and Biotechnology
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    • v.19 no.4
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    • pp.339-345
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    • 2009
  • We evaluated the activity and abundance of the crude-oil-degrading bacterium Nocardia sp. H17-1 during bioremediation of oil-contaminated soil, using real-time PCR. The total petroleum hydrocarbon(TPH) degradation rate constants(k) of the soils treated with and without H17-1 were $0.103\;d^{-1}$ and $0.028\;d^{-1}$ respectively. The degradation rate constant was 3.6 times higher in the soil with H17-1 than in the soil without H17-1. In order to detect and quantify the Nocardia sp. H17-1 in soil samples, we quantified the genes encoding 16S ribosomal RNA(16S rRNA), alkane monooxygenase(alkB4), and catechol 2,3-dioxygenase(23CAT) with real-time PCR using SYBR green. The amounts of H17-1 16S rRNA and alkB4 detected increased rapidly up to 1,000-folds for the first 10 days, and then continued to increase only slightly or leveled off. However, the abundance of the 23CAT gene detected in H17-1-treated soil, where H17-1 had neither the 23CAT gene for the degradation of aromatic hydrocarbons nor the catechol 2,3-dioxygenase activity, did not differ significantly from that of the untreated soil($\alpha$=0.05,p>0.22). These results indicated that H17-1 is a potential candidate for the bioaugmentation of alkane-contaminated soil. Overall, we evaluated the abundance and metabolic activity of the bioremediation strain H17-1 using real-time PCR, independent of cultivation.

Overwintering Site and Occurrence Dynamics of Scrobipalpa salinella (Zeller) (Lepidoptera: Gelechiidae) (퉁퉁마디뿔나방 월동 서식처와 발생동태)

  • Paik, Chae-Hoon;Lee, Geon-Hwi;Choi, Man-Young;Noh, Tae-Hwan;Shim, Hyeong-Kwon
    • Korean journal of applied entomology
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    • v.52 no.2
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    • pp.71-74
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    • 2013
  • The moving period and overwinteing site of Scrobipalpa salinella (Zeller) were investigated in Gimje, Jeonbuk, and Shinan, Jeonnam in the glasswort field. Densities of Scrobipalpa salinella larvae were started to increase from mid-September in halophytes, such as Suaeda asparagoides, S. japonica, and S. maritima, rather than glasswort. S. salinella was overwintering inside the halophytes in old larva. Density ratio of overwintering S. salinella in Suaeda asparagoides, S. japonica, and S. maritima were 20.5, 28.4 and 51.1%, respectively. Overwintering population was highest in S. maritima among halophytes. The occurrence of first adult in the next spring was from April 19 to April 20 in Gimje, Jeonbuk, and Shinan, Jeonnam.

The trend of prevalence of pain in Korea from 2005 to 2016

  • Cho, Sang-Hyeon;Kim, Yong-Min;Lee, Jae-Ho;Kim, Hyun-Soo;Song, Jae-Seok
    • The Korean Journal of Pain
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    • v.33 no.4
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    • pp.352-358
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    • 2020
  • Background: Korean society is afflicted with rapid aging. Aging is a risk factor for pain, and pain can reduce patients' quality of life. Thus, adequate management and monitoring of changing trends accompanying the demographic shift are highly valuable. However, this study was conducted because no studies have investigated the recent changes in the prevalence of pain. Methods: The extent of the prevalence of pain was determined by questions related to quality of life based on the data derived from the Korea National Health and Nutrition Survey (KNHNS) from 2005 to 2016. The annual frequencies of the pain group and severe pain group were calculated using the survey questionnaire. Multiple logistic regression analysis was performed to determine possible differences in prevalence by year. Results: The prevalence of pain in all populations was 30.6% in 2005 and 18.9% in 2016. The average prevalence from 2005 to 2016 was 21.9%. A declining trend occurred over time with an odds ratio of 0.929 per year (95% CI: 0.921-0.938). The prevalence of severe pain was 2.35% in 2005 and 1.88% in 2016. Likewise, a decrease was observed over time, with an odds ratio of 0.920 per year at 95% CI 0.901-0.939. The decline in age-/sex-stratified analysis also showed a statistically significant trend in all groups. Conclusions: The prevalence of pain in Korean society, based on the KNHNS, has declined since 2005. Such a trend was observed in all ages and sexs, and was most significant in the elderly.