• Title/Summary/Keyword: out-migration

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A Study on the Efficiency Improvement of Existing Pool-and-Weir Type Fishway in Namgang Weir (남강수중보의 기존 전면월류형 계단식 어도의 효율성 개선에 관한 연구)

  • Lee, Hyeong-Rae;Kim, Ki Heung;Park, Ho Chul
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.17 no.2
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    • pp.61-71
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    • 2014
  • A river fishway is a hydraulic structure enabling fish to overcome stream obstructions such as dams and weirs. The main aim of this paper is to investigate the collectibility of upstream-migrating fishes and hydraulic problems in pool-and-weir type fishway which has been established for upstream-migration at Namgang weir in the downstream of Namgang dam, and to grope for improvement measures which pool-and-weir type fishway can be switched to pool-and-partial weir type fishway through hydraulic field experiment. Exsisting fishway had problems which upstream-migrating fishes can not take a rest due to the seiche and vortex phenomena in pools and migrate to upstream because of height difference in entrance pool. In order to prevent hydraulically the seiche and vortex phenomena and establish rest area for fishes in each pool, we carried out hydraulic field experiments. In the fishway, it was to improve pool-and-weir into pool-and-partil weir, to decrease the height difference in entrance pool, and to reduce oriffice velocity of each pool. Also, we investigated fishes collectibility of after improving fishway for 6 days in September 2013. To resolve chronic problems(seiche-vortex phenomena and rest area for fishes), as weirs were remodeled into partial weir only which central part of weirs was part of non-overflow weir, we confirmed results that pool-and-weir type fishway could be switched to efficient pool-and-partial weir type fishway with relatively simple construction and low cost. Type-B which has the closed oriffices and the parts of non-overflow has the ideal conditions, but this conditions are limited to fishway of Namgang weir used in this study. Representative Ice-habor type fishway is pool-and-partial weir type fishway which has together parts of overflow and oriffices, and has excellent ability of upstream-migration. To switch from pool-and-weir type fishway to pool-and-partial weir type fishway, the size of oriffice has to be regulated by the discharge of fishway and the dimension on parts of non-overflow and overflow in weirs. Entrance pool is important facility which upstream-migrating fishes have to not only be collect but also charge with energy. In this study, entrance-pool is temporary and roughly-built, but fishes gather together more than the case of no entrance-pool. In the case of fishway which was protruded to downstream, as entrance of fishway turns toward or parallels to weir, the collectibility of fishway was excellent by attraction water.

Seismic interval velocity analysis on prestack depth domain for detecting the bottom simulating reflector of gas-hydrate (가스 하이드레이트 부존층의 하부 경계면을 규명하기 위한 심도영역 탄성파 구간속도 분석)

  • Ko Seung-Won;Chung Bu-Heung
    • 한국신재생에너지학회:학술대회논문집
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    • 2005.06a
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    • pp.638-642
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    • 2005
  • For gas hydrate exploration, long offset multichannel seismic data acquired using by the 4km streamer length in Ulleung basin of the East Sea. The dataset was processed to define the BSRs (Bottom Simulating Reflectors) and to estimate the amount of gas hydrates. Confirmation of the presence of Bottom Simulating reflectors (BSR) and investigation of its physical properties from seismic section are important for gas hydrate detection. Specially, faster interval velocity overlying slower interval velocity indicates the likely presences of gas hydrate above BSR and free gas underneath BSR. In consequence, estimation of correct interval velocities and analysis of their spatial variations are critical processes for gas hydrate detection using seismic reflection data. Using Dix's equation, Root Mean Square (RMS) velocities can be converted into interval velocities. However, it is not a proper way to investigate interval velocities above and below BSR considering the fact that RMS velocities have poor resolution and correctness and the assumption that interval velocities increase along the depth. Therefore, we incorporated Migration Velocity Analysis (MVA) software produced by Landmark CO. to estimate correct interval velocities in detail. MVA is a process to yield velocities of sediments between layers using Common Mid Point (CMP) gathered seismic data. The CMP gathered data for MVA should be produced after basic processing steps to enhance the signal to noise ratio of the first reflections. Prestack depth migrated section is produced using interval velocities and interval velocities are key parameters governing qualities of prestack depth migration section. Correctness of interval velocities can be examined by the presence of Residual Move Out (RMO) on CMP gathered data. If there is no RMO, peaks of primary reflection events are flat in horizontal direction for all offsets of Common Reflection Point (CRP) gathers and it proves that prestack depth migration is done with correct velocity field. Used method in this study, Tomographic inversion needs two initial input data. One is the dataset obtained from the results of preprocessing by removing multiples and noise and stacked partially. The other is the depth domain velocity model build by smoothing and editing the interval velocity converted from RMS velocity. After the three times iteration of tomography inversion, Optimum interval velocity field can be fixed. The conclusion of this study as follow, the final Interval velocity around the BSR decreased to 1400 m/s from 2500 m/s abruptly. BSR is showed about 200m depth under the seabottom

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Roles and Importance of Microbes in the Radioactive Waste Disposal (방사성폐기물 처분에서 미생물의 역할과 중요성)

  • Baik, Min-Hoon;Lee, Seung-Yeop;Roh, Yeol
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.7 no.1
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    • pp.63-72
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    • 2009
  • Recently the importance and interest for the microbes has been increased because several important results for the effects of microbes on the radioactive waste disposal have been published continuously. In this study, research status and major results on the various roles and effects of microbes in the radioactive waste disposal have been investigated. We investigated and summarized the roles and major results of microbes in a multi-barrier system consisting of an engineered barrier and a natural barrier which is considered in radioactive waste disposal systems. For the engineered barrier, we discussed about the effects of microbes on the corrosion of a waste container and investigated the survival possibility and roles of microbes in a compacted bentonite buffer. For the natural barrier, the roles of microbes present in groundwaters and rocks were discussed and summarized with major results from natural analogue studies. Furthermore, we investigated and summarized the roles and various interactions processes of microbes and their effects on the radionuclide migration and retardation including recent research status. Therefore, it is expected that the effects and roles of microbes on the radioactive waste disposal can be rigorously evaluated if further researches are carried out for a long-term behavior of the disposal system in the deep geological environments and for the effects of microbes on the radionuclide migration through geological media.

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A Development of Remote Bird Observation System Using FMCW RADAR (FMCW 레이더를 이용한 원격 조류(鳥類) 관측 시스템 개발)

  • Lee, Hee-Yong;Hwang, Hun-Gyu;Choi, Myung-Gil
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.17 no.3
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    • pp.247-256
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    • 2014
  • Recently, camera and RADAR are used for more effective and accurate observation of the bird migration. In recent years, many researches on the bird migration using RADAR are undertaking and in active, thus causes the advent of "RADAR ornithology" as a new academic field. Due to the lack of accessibility, economic feasibility and mobility of weather RADAR, airport searching RADAR and tracking RADAR, Nowadays, a marine RADAR is widely used for a bird observation. In this paper, we deals with a study on development of a remote bird observation system using marine FMCW RADAR, which monitors, records and analyzes bird movement by RADAR image processing and target recognition technology. Also, we conduct first test and second test for availability of the developed system, and verify the system to apply in bird observation domain. Consequently, we figured problems out, and correct the problems to improve the system. The developed system can apply in other domains such as environment evaluation. In the future, the system needs to improve accuracy of statistics and to track migration route of bird.

Regional Ecological Network Design for Wild Animals' Movement Using Landscape Permeability and Least-cost Path Methods in the Metropolitan Area of Korea (경관투과성 및 최소비용경로 분석을 통한 수도권 지역의 광역생태축 구축 연구)

  • Lee, Dong-Kun;Song, Won-Kyong;Jeon, Seong-Woo
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.11 no.3
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    • pp.94-106
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    • 2008
  • As populations inhabiting in natural ecosystem are fragmented by artificial barriers and habitats are destructed by development, extinction possibility of species is getting higher. It is necessary to design and to manage conservation areas and corridors considering animals' movement and migration for sustainable species diversity in present circumstances. 'Least-cost modeling' is one commonly employed approach in which dispersal costs are assigned to distinct habitat types and the last-costly dispersal paths among habitat patches are calculated using a geographical information system (GIS). This study aims to design ecological corridor using least-cost path method and to apply it to a regional ecological network considering movability of medium-large size mammals. This study was carried out over the metropolitan area, which has been deforested by rapid urbanization. Nevertheless there is connected with Gangwon province, Baekdudaegan mountain range and DMZ, considered where many forest species can migrate to this region. This study employs such an approach to develop least-cost path models for medium-large size mammals, have inhabited for this entire region. Considering those species, two forest areas as a source of species supply and forest areas more than 1,000ha are selected as focal forest areas. Movement and migration paths from species supply sources to focal forest areas are calculated by applying landscape permeability theory using land cover map, road density map and land slope map. Results showed least-cost paths from species supply sources to focal forest areas on two species. Wildcat and roe deer are different in some least-cost paths caused by their landscape permeability but paths show generally same specifics. The result of considering regional distribution of expected movement and migration paths to regional ecological network, low altitude mountains of western metropolitan area are evaluated important area for species connectivity. In national or regional levels ecological connectivity is essential to promote species diversity and to preserve integrated ecosystem. This study concludes that developing least-cost models from similar empirical data could significantly improve the utility of these tools.

Detailed Processing and Analysis on the Single-channel Seismic Data for Site Survey of Daecheon-Wonsando Subsea Tunnel (대천-원산도 해저터널 부지조사를 위한 단일채널 탄성파자료의 정밀 처리 및 분석)

  • Kim, Won-Sik;Park, Keun-Pil;Kim, Hyun-Do;Cheong, Snons;Koo, Nam-Hyung;Lee, Ho-Young;Park, Eui-Seob
    • Geophysics and Geophysical Exploration
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    • v.13 no.4
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    • pp.336-348
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    • 2010
  • The Single-channel seismic survey with the source of bubble pulser and drilling survey was carried out in 2008 and 2009 for the site survey of Daecheon-Wonsando area, which was a proposed area of Korea-China subsea tunnel. The goal of this study is to analyze the depth and characteristics of acoustic basement for the stability assessment and tunnel design in this proposed area through combining drilling data with this single-channel seismic data after detailed processing. For this purpose, among the data processing schemes which are usually applied to multi-channel seismic data, we applied the F-K filtering to eliminate the AC(alternating current) noise and the post-stack depth migration to produce depth section. As a result, we verified that the improved depth section could be obtained from single-channel seismic data, and the distribution and characteristics of basement could be analyzed in survey area through the combined analysis with drilling data. However, we could not interpret the detailed structures, fault and fracture zone, due to the quality of bubble pulser source and single-channel data. We expect that those detailed structures can be analyzed when higher resolution seismic data is provided. Therefore, we recommend some items for future seismic survey of subsea tunnel to obtain the high resolution seismic data.

Antineoplastic Effect of Several Herbal Medicines on SNU-80 Anaplastic Thyroid Carcinoma Cell Line (황기, 당귀, 칠피, 천화분의 역형성갑상선암세포 SNU-80에 대한 항암효과)

  • Yeo, Hyun Soo;Lee, Min Hye;Ko, Seong Gyu;Choi, You Kyung;Jun, Chan Young;Park, Jong Hyeong
    • Journal of Society of Preventive Korean Medicine
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    • v.18 no.1
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    • pp.83-92
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    • 2014
  • Objective : This study was performed to investigate the antineoplastic effect of Astragalus membranaceus, Angelica gigas, Rhus verniciflua Stokes and Trichosanthes kirilowii on SNU-80 anaplastic thyroid carcinoma cell line. Method : We examined whether our herbal medicines decreases cell growth rate of SNU-80 using MTT assay. We performed western blot analysis to verify that our herbal medicines induces apoptosis via caspase-dependent mechanism. We also performed wound healing assay and transwell invasion assay to investigate whether our herbal medicines affects the migration and invasion of anaplastic cancer cells, SNU-80. We also carried out ELISA assay to know our herbal medicines suppresses the expression of proinvasive molecules, such as VEGF and MMP-2 secreted from SNU-80. Results : MTT assay demonstrates that Angelica gigas, Rhus verniciflua Stokes, and Trichosanthes kirilowii suppressed strongly the growth of SNU-80. Western blot analysis demonstrates that Trichosanthes kirilowii induces apoptosis activating the cleavages of caspases (caspase-8, caspase-3) and PARP. Wound healing assay demonstrates that Rhus verniciflua Stokes, and Trichosanthes kirilowii inhibited the migration of SNU-80. Transwell invasion assay demonstrates that Rhus verniciflua Stokes, and Trichosanthes kirilowii inhibited the invasion of SNU-80. Elisa assay demonstrates that Astragalus membranaceus, Angelica gigas, Rhus verniciflua Stokes, and Trichosanthes kirilowii suppressed the expression of VEGF and MMP-2. Conclusion : We could conclude that several herbal medicines suppresses the growth and inhibits the migration and invasion of SNU-80 which is anaplastic thyroid cancer cells. Especially, Rhus verniciflua Stokes, Trichosanthes kirilowii had stronger anti-cancer effect suggesting that we can apply them to treat anaplastic thyroid cancer.

Multi-Cultural Space and Glocal Ethics : From Cultural Space of Transnational Capitalism to Space of Recognition Struggle (다문화공간과 지구-지방적 윤리 : 초국적 자본주의의 문화공간에서 인정투쟁의 공간으로)

  • Choi, Byung-Doo
    • Journal of the Korean association of regional geographers
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    • v.15 no.5
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    • pp.635-654
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    • 2009
  • Recently, concepts of multicultural society and/or multiculturalism have been not only widely discussed across several disciplines, but also actively promoted in government's policy, as the in-flow of foreign immigrants has increased rapidly. This paper suggests the term 'multicultural space' instead of multicultural society in a sense that both international migration of immigrants and their accommodation to a certain locality presuppose a spatial dimension. This paper also points out that the term multiculturalsim should be used very carefully, because this term includes a normative character implied in a sense of recognition of ethnic and cultural diversity and difference on the one hand, and an ideological one reflected on strategic policies of capital and the state on the other. On the basis of recognition of these problems, this paper tries to reformulate spatially the concept of muticultural society which has been supposed to be constructed due to rapidly increasing foreign immigrants, emphasizing some usefulness of multi-scalar approach. It then analyzes economic and political contexts of transnational migration, providing a criticism of multiculturalism as an ideological logic of capital and the state in transnational captialism. Finally it put a stress upon importance of struggle for spaces of recognition as a new glocal ethics in the age of post-globalization.

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AHP Study on the Decision Making Factors of Farm-Returning and Rural-Returning: Focusing on the Determinants of Migration Area (귀농·귀촌 의사결정요인에 관한 AHP 분석 연구: 이주지역 선택 결정요인을 중심으로)

  • Lee, Won Suk;Jang, Sang-hyun;Choi, Joowon;Shin, Yongtae
    • KIPS Transactions on Computer and Communication Systems
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    • v.10 no.3
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    • pp.81-92
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    • 2021
  • As the aging population of Korean agriculture and rural areas and the decline of the agricultural population are gradually deepening, the influx of population through returning to farming and rural areas is urgently needed. To this end, the most important problems to be solved were the lack of information that would help those who want to return to farming or rural areas when making decisions. Therefore, a survey was conducted for AHP analysis on related experts to find out the information (decision factors) required when selecting a return-to-farm or return-to-country migration area through this study. The AHP analysis showed that "Economic factors" were the most important among the three items in the primary class, while "Housing and land prices", "Metropolitan accessibility and traffic" and "Residential information" were the most important in the secondary class. The results of these studies are reflected in the information system to systematically support the decision-making of those who wish to return to farming or rural areas.It is hoped that it will be indirectly helpful and ultimately contribute to the revitalization and development of Korean agriculture and rural areas, which are aging.

Exposure Assessment of Heavy Metals Migrated from Glassware on the Korean Market (국내 유통 식품용 유리제의 중금속 노출 평가)

  • Kim, Eunbee;Hwang, Joung Boon;Lee, Jung Eun;Choi, Jae Chun;Park, Se-Jong;Lee, Jong Kwon
    • KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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    • v.28 no.1
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    • pp.15-21
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    • 2022
  • The purpose of our study was to investigate the migration level of lead (Pb), cadmium (Cd), and barium (Ba) from glassware into a food simulant and to evaluate the exposure of each element. The test articles were glassware, including tableware, pots, and other containers. Pb, Cd, and Ba were analysed by Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES). The analytical performance of the method was validated in terms of its linearity, limit of detection (LOD), limit of quantification (LOQ), recovery, precision, and uncertainty. The monitoring was performed for 110 samples such as glass cups, containers, pots, and bottles. a food simulant. Migration test was conducted at 25? for 24 hours in a dark place using 4% acetic acid as a food simulant. Based on the data; exposure assessment was carried out to compare the estimated daily intake (EDI) to the human safety criteria. The risk levels of Pb and Ba determined in this study were approximately 1.9% and 0.3% of the provisional tolerable weekly intake (PTWI) and tolerable daily intake (TDI) value, respectively, thereby indicating a low exposure to the population.