• Title/Summary/Keyword: Population dynamics

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Effects of Different Additives on Fermentation Characteristics and Protein Degradation of Green Tea Grounds Silage

  • Wang, R.R.;Wang, H.L.;Liu, X.;Xu, C.C.
    • Asian-Australasian Journal of Animal Sciences
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    • v.24 no.5
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    • pp.616-622
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    • 2011
  • This study evaluated the fermentation characteristics and protein degradation dynamics of wet green tea grounds (WGTG) silage. The WGTG was ensiled with distilled water (control), or lactic acid bacteria (LAB), enzyme (E), formic acid (FA) and formaldehyde (FD) prior to ensiling. Three bag silos for each treatment were randomly opened at 0, 3, 7, 14, 28 and 60 days after anaerobic storage. For all the treatments, except for FA, there was a rapid decline in pH during the first 7 days of ensiling. LAB treatment had higher lactic acid content, lower ammonia-N ($NH_3$-N) and free-amino nitrogen (FAA-N) contents than other treatments (p<0.05). E treatment had higher lactic acid, water-soluble carbohydrates (WSC) and non-protein nitrogen (NPN) content than the control (p<0.05). FA treatment had higher $NH_3$-N and FAA-N content than the control (p<0.05). FD treatment had lower NPN and FAA-N content than the control, but it did not significantly inhibit the protein degradation when compared to LAB treatment (p>0.05). Results indicate that LAB treatment had the best effect on the fermentation characteristics and protein degradation of WGTG silage.

Towards a hierarchical global naming framework in network virtualization

  • Che, Yanzhe;Yang, Qiang;Wu, Chunming
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.7 no.5
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    • pp.1198-1212
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    • 2013
  • Network virtualization enables autonomous and heterogeneous Virtual Networks (VNs) to co-exist on a shared physical substrate. In a Network Virtualization Environment (NVE), the fact that individual VNs are underpinned by diverse naming mechanisms brings about an obvious challenge for transparent communication across multiple VN domains due to the complexity of uniquely identifying users. Existing solutions were mainly proposed compatible to Internet paradigm with little consideration of their applications in a virtualized environment. This calls for a scalable and efficient naming framework to enable consistent communication across a large user population (fixed or mobile) hosted by multiple VNs. This paper highlights the underlying technical requirements and presents a scalable Global Naming Framework (GNF), which (1) enables transparent communication across multiple VNs owned by the same or different SPs; (2) supports communication in the presence of dynamics induced from both VN and end users; and (3) greatly reduces the network operational complexity (space and time). The suggested approach is assessed through extensive simulation experiments for a range of network scenarios. The numerical result clearly verifies its effectiveness and scalability which enables its application in a large-scale NVE without significant deployment and management hurdles.

Assessment of Neuronal Cell-Based Cytotoxicity of Neurotoxins from an Estuarine Nemertean in the Han River Estuary

  • Kwon, Yeo Seon;Min, Seul Ki;Yeon, Seung Ju;Hwang, Jin ha;Hong, Jae-Sang;Shin, Hwa Sung
    • Journal of Microbiology and Biotechnology
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    • v.27 no.4
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    • pp.725-730
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    • 2017
  • A heteronemertean, Yininemertes pratensis, was collected in Han River Estuary, South Korea. This estuarine nemertean has been known by the local fishermen for harmful effects to the glass eels, juveniles of Japanese eel Anguilla japonica, migrating to fresh water. The present study confirmed the neurotoxic effects of this heteronemertean ribbon worm at the cellular level. Derivative types of neurotoxic tetrodotoxin (TTX), 5,11-dideoxy TTX (m/z 288) and 11-norTTX-6(S)-01 (m/z 305.97), were identified through HPLC and MALDI-TOF MS. However, significant neurotoxicity was confirmed in the fraction containing an undefined molecule corresponding to the 291.1 (m/z) peak, when tested in rat primary astrocytes and dorsal ganglion cells. This study is the first to report neurotoxins of the estuarine nemertean, fairly abundant in the Han River estuary, and suggests the long-term monitoring of population dynamics and surveillance of the toxicity in this river estuary.

Community Structure, and Size and Age Distribution of Conifers in Subalpine Korean Fir (Abies koreana) Forest in Mt. Chiri (지리산 아고산대 구상나무림의 군집구조 및 침엽수의 직경과 연령분포)

  • Cho, Do-Soon
    • The Korean Journal of Ecology
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    • v.17 no.3
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    • pp.415-424
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    • 1994
  • Community structure, size and age distribution of tree species of the subalpine Korean fir (Abies koreana) forest at the elevation of 1, 400~1, 700m were strudied in the north-west side of Chonwangbong Peak (1915m) in Mt. Chiri for the purpose of better understanding of the population dynamics of Abies koreana. Eight 20m X 20m permanent quadrats were established in 1991, and trees $\geq$ 2.5cm DBH for all species were marked with numbered aluminum tag, and saplings of Korean fir and Korean pine (Pinus koraiensis) were also tagged with aluminum sheet. These two conifer species comprised more than 60% of the total density and total basal area of the community. Quercus mongolica and Acer pseudo-sieboldianum were subdominats. Oridination study showed that cool temperate species such as Sorbus commixta, Betula costata, Acer tschonoskii and Acer ukurunduense occurred in close association with Abies koreana and Pinus koraiensis. Major tree species, especially Abies koreana and Pinus koraiensis, were well represented in samller size classes, indicating that they were regenerating well. Age distributuion of the Abies koreana and Pinus koraiensis showed that the former has longer physiological longevity than the latter, and that establishment were episodic and varied with sites, which implies the importance of the role of natural and artificial disturbances in this Abies kireana forest.

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The Trend of Housing Design and Town Planning of New Towns in Indonesia (인도네시아 신도시의 주거디자인 및 단지계획 경향)

  • Megawati, Dewi Ratih;Ju, Seo Ryeung;Hanan, Himasari
    • Journal of the Korean housing association
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    • v.25 no.5
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    • pp.11-20
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    • 2014
  • Recent changes in the dynamics of national economies, market liberalization, changes in technologies and movement of capital have had a major effect on the Asian Pacific region since the early 1990's, as there has been an increasing role for foreign housing developers in those countries that experienced economic liberalization, high urbanization rates and reforms in the housing sectors. Recently the cosmopolitan cities of Indonesia attracted a global interest due to its rapid economic development and great potential of population and natural resources. New town development emerged as one of the solutions to reduce urbanization problems in Indonesia. This study aims to explore the contemporary planning principles of new town developments in representative new town projects supplied by of major housing development companies in Indonesia. We conducted case study on the new town named Kota Baru Parahyangan, which is located in outskirt of Bandung, the third biggest city in Indonesia and supplied by PT. Belaputra Intiland. As a result of this study, we can identify unique characteristics of new town development in Indonesia.

Bionomics and Systematics of Diplopoda in Korea I. The Life-ycle and Population Dynamics of Anaulaiulus koreanus koreanus (Verhoeff) (Diplopoda Julidae) (한국산 노래기류의 분류 및 생태 1. 계림갈퀴노래기 ( Anaulaciulus Koreanus koreanus ( Verhoeff )) 의 생활사와 개체군 동태)

  • Kim, Tae-Heung;Kil-Young Lim
    • The Korean Journal of Ecology
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    • v.16 no.2
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    • pp.155-157
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    • 1993
  • The life-cycle and seasonal abundance of Anaulaciulus koreanus koreanus was studied at Hwang-dong, Chonbuk Province, Korea from October 1990 to February 1992. The egg hatches in spring and the pupoid stage is passed through within the egg shell. The juvenile develops as far as stadium IX by the third year following the birth. Pairing and oviposition take place in the fourth year spring when females are at stadium XI. They seem to live one or two years more after egg-laying. Anamorphosis was observed in this species. Abundance of A. koreanus koreSanus increases from April to May when there appears thefirst peak. It fals gradualy thereafter and the species spends summer months underground from July to September. The second peak appears in October and the activity decreases again in November getting ready to overwinter. The first peak arises from a large number of individuals of 2 and 3 year old overwintered plus newly hatched spring juveniles, and the second from 1 to 3 years old wanderings. Inactivity observed in the species during summer and winter seasons appears to be a temporal due to the extreme temperatures.

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Change of Carabid Beetle (Coleoptera, Carabidae) Diversity and Species Composition after Flooding Events in Woopo Wetlands (우포늪 범람에 의한 먼지벌레류(딱정벌레목, 딱정벌레과)의 다양성과 종조성 변화)

  • Do, Yun-O;Jang, Min-Ho;Kim, Dong-Kyun;Joo, Gea-Jae
    • Korean Journal of Ecology and Environment
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    • v.40 no.2
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    • pp.346-351
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    • 2007
  • Change of carabid beelte (Coleoptera, Carabidae) diversity and population structures in Woopo Wetlands (Changneung-Gun, Gyeungsangnam-Do, S. Korea) were investigated after flooding events. During the investigation period, 11 species belonging to five genera were identified. Dolichus halensis halensis(Schaller), Chlaenius (Ch.) pallipes Gebler, Ch. (Ilaenchus) naeviger Morawitz, and Pheropsophus (Stenaptinus) jessoensis Morawitz were the predominant species in Woopo Wetlands. Floods occurred twice, August and September in 2004. After the flooding events, species diversity decreased and species assemblage structures changed dramatically. Changes of the diversity and species assemblage structures were more evident in August then in September, because water level was much higher and inundation period was longer than September. A non-linear patterning algorithm of the Self-Organizing Map (SOM) was applied to discover the relationship between flooding events and carabid beetles community dynamics. Although abundance of the majority species decreased after the flooding events, that of the predominant species increased. Further detailed studies on species distribution and emigration patterns will likely bring a new insight in understanding of the adaptation mechanism of carabid beetles in wetlands.

The Directions of Supporting Policy and Education Strategy for Young Agricultural Workforce (농업후계인력 육성을 위한 농촌청소년교육 및 지원방향)

  • Oh, Hae-Sub;Kim, Jeong-Joo
    • Journal of Agricultural Extension & Community Development
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    • v.9 no.2
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    • pp.185-197
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    • 2002
  • The supporting system for agricultural workforce and education strategy has been changing both domestically and worldwide range term. To change the fundamental directions, much more needs to be learned about the process of structural adjustment regarding the dynamics of the agricultural and rural sectors. A rural development doctrine must pay more attention to the ongoing problems of population imbalance and the dissolution of the countryside. The focus should be young people prefer to live in cities because there are more opportunities, services, and great personal fulfillment. This paper was described the effective fostering directions of young agricultural workforce and educational program to prepare future and young farmer for teaching careers in agriculture, food, farm management, and marketing. To achieve these goals, the specific approaches are 1) establish the strong partnership between related organizations of agricultural business, 2) strengthen the management and marketing education of products, 3) create the various in-farming or out-fanning incomes including green tourism, 4) enhance the aggressive marketing strategies by Internet, Telephone, and TV etc, 5) make the association among the same items for the effective research and risk management.

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Ionic Compositions of PM2.5 during Summer and Winter in the Downtown Area of Jeju City in Jeju Island (제주시 도심지역에서 여름과 겨울의 PM2.5 이온조성 특성)

  • Lee, Ki-Ho;Hu, Chul-Goo
    • Journal of Environmental Science International
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    • v.26 no.4
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    • pp.447-456
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    • 2017
  • Chemical properties of aerosols were investigated by analyzing the inorganic water-soluble content in $PM_{2.5}$ collected in the downtown area of Jeju City in Jeju Island. Due to an increase in both the number of visiting tourists and the size of local population, the number of cars in this area is increasing, causing an increase in $PM_{2.5}$. Eight $PM_{2.5}$-bound major inorganic ions were analyzed during the summer and winter periods. The water-soluble inorganic component represents a significant fraction of $PM_{2.5}$. In particular, secondary inorganic aerosols contribute 36.2% and 47.5% of $PM_{2.5}$ mass in summer and winter, respectively. Nitrate concentrations increase for $[NH_4{^+}]/[SO_4{^{2-}}]$>1.5, and excess ammonium, which is necessary for ammonium nitrate formation, is linearly correlated with nitrate. These results are clearly observed during the winter because conditions are more conducive to the formation of ammonium nitrate. A significant negative correlation between Nitrogen Oxidation Ratio (NOR) and temperature was observed. The obtained results can be useful for a better understanding of the aerosol dynamics in the downtown area in Jeju City.

A Study on Optimization of Motion Parameters and Dynamic Analysis for 3-D.O.F Fish Robot (3 자유도 물고기 로봇의 동적해석 및 운동파라미터 최적화에 관한 연구)

  • Kim, Hyoung-Seok;Quan, Vo Tuong;Lee, Byung-Ryong;Yu, Ho-Yeong
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.33 no.10
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    • pp.1029-1037
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    • 2009
  • Recently, the technologies of mobile robots have been growing rapidly in the fields such as cleaning robot, explosive ordnance disposal robot, patrol robot, etc. However, the researches about the autonomous underwater robots have not been done so much, and they still remain at the low level of technology. This paper describes a model of 3-joint (4 links) fish robot type. Then we calculate the dynamic motion equation of this fish robot and use Singular Value Decomposition (SVD) method to reduce the divergence of fish robot's motion when it operates in the underwater environment. And also, we analysis response characteristic of fish robot according to the parameters of input torque function and compare characteristic of fish robot with 3 joint and fish robot with 2 joint. Next, fish robot's maximum velocity is optimized by using the combination of Hill Climbing Algorithm (HCA) and Genetic Algorithm (GA). HCA is used to generate the good initial population for GA and then use GA is used to find the optimal parameters set that give maximum propulsion power in order to make fish robot swim at the fastest velocity.