• Title/Summary/Keyword: 인공 계

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Characteristics of Heavy Metal Removal from Aqueous Solutions using Leather Industry by-products (피혁산업 부산물에 의한 용존 중금속 제거 특성)

  • Kim, Keun-Han;Lee, Nam-Hee;Paik, In-Kyu;Park, Jae-Hyung;Yang, Jae-Kyu
    • Journal of Korean Society of Environmental Engineers
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    • v.32 no.5
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    • pp.417-426
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    • 2010
  • In this study, ten different bio-adsorbents were prepared by immobilization of vegetable tannins such as mimosa(Catechol Tannin) and chestnut(Pyrogallol Tannin) on the collagen matrix which was derived from during leather manufacturing processing. Removal efficiency of Cu(II), Cd(II), Zn(II), Pb(II), Cr(III) by each bio-adsorbent in synthetic wastewater was evaluated by a laboratory-scale batch reactor at different reaction conditions. When mimosa was used as a vegetable tannin, the penetration efficiency of mimosa into the inner bundle of fiber depended on the dose of the naphthalene condensated penetrant; 3% ${\geq}$ 1.5% > 0%. For all bio-adsorbents, removal of heavy metal ions was not observed below pH 3.0 but was rapidly increased between pH 3.0 and 6.0, showing near complete removal of all heavy metal ions except Zn(II) above pH 6.0. Removal of Cr(III) was quite similar for all bio-adsorbents while removal of Cu(II), Zn(II) and Pb(II) was higher by bio-adsorbents immobilized with chestnut than that by mimosa. Adsorption of Pb(II) and Cu(II) by S10 bio-adsorbent was little affected by the presence of monovalent and divalent electrolytes as well as variation of 1000 times ionic concentration with $NaNO_3$.

Comparative Evaluation of UAV NIR Imagery versusin-situ Point Photo in Surveying Urban Tributary Vegetation (도심소하천 식생조사에서 현장사진과 UAV 근적외선 영상의 비교평가)

  • Lee, Jung-Joo;Hwang, Young-Seok;Park, Seong-Il;Um, Jung-Sup
    • Journal of Environmental Impact Assessment
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    • v.27 no.5
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    • pp.475-488
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    • 2018
  • Surveying urban tributary vegetation is based mainly on field sampling at present. The tributary vegetation survey integrating UAV NIR(Unmanned Aerial Vehicle Near Infrared Radiance) imagery and in-situ point photo has received only limited attentions from the field ecologist. The reason for this could be the largely undemonstrated applicability of UAV NIR imagery by the field ecologist as a monitoring tool for urban tributary vegetation. The principal advantage of UAV NIR imagery as a remote sensor is to provide, in a cost-effective manner, information required for a very narrow swath target such as urban tributary (10m width or so), utilizing very low altitude flight, real-time geo-referencing and stereo imaging. An exhaustive and realistic comparison of the two techniques was conducted, based on operational customer requirement of urban tributary vegetation survey: synoptic information, ground detail and quantitative data collection. UAV NIR imagery made it possible to identify area-wide patterns of the major plant communities subject to many different influences (e.g. artificial land use pattern), which cannot be acquired by traditional field sampling. Although field survey has already gained worldwide recognition by plant ecologists as a typical method of urban tributary vegetation monitoring, this approach did not provide a level of information that is either scientifically reliable or economically feasible in terms of urban tributary vegetation (e.g. remedial field works). It is anticipated that this research output could be used as a valuable reference for area-wide information obtained by UAV NIR imagery in urban tributary vegetation survey.

Review on Ocean Carbon Sequestration through Direct Injection (심층 분사를 통한 해양 이산화탄소 격리 기술 소개)

  • Park, Young-Gyu;Choi, Sang-Hwa;Matsumoto, Katsumi;Lee, Jung-Suk;Gang, Seong-Gil;Hwang, Jin-Hwa
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.10 no.2
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    • pp.118-124
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    • 2007
  • The oceans could absorb almost all the anthropogenic carbon dioxide the mankind has been producing eventually, but in the nature the air-sea $CO_2$ exchange occurs very slowly and to lower the atmospheric $CO_2$ concentration substantially $CO_2$ must be injected to the interior of the ocean directly. If we inject $CO_2$ collected at the major $CO_2$ sources into the international waters in the Philippine Sea or east of Japan, we could store the $CO_2$ in the oceans effectively for a few hundred years. When $CO_2$ is dissolved into the water, PH drops. The creatures adapted to the deep oceans where environment is very stable could be affected by even a small change in pH significantly. If, therefore, we are to inject $CO_2$ into the oceans, we must assess the effect of $CO_2$ injection in the marine ecosystem beforehand. Only when the damage to the marine ecosystem is smaller than the benefit from the $CO_2$ injection, $CO_2$ injection is effective.

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Penetrations of flupyrazofos against Plutella xylostella(Lepidoptera :Yponomeutidae) and Spodoptera exigua(Lepidoptera : Noctuidae) (배추좀나방과 파밤나방에 대한 flupyrazofos의 체벽 투과량)

  • Lee, Sang-Guei;Hwang, Chang-Yeon;Han, Man-Jong;Yoo, Jai-Ki;Lee, Hoi-Seon
    • The Korean Journal of Pesticide Science
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    • v.4 no.1
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    • pp.44-50
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    • 2000
  • Tolerance mechanism to flupyrazofos was examined with Plutella xylostella (L.) and Spodoptera exigua by investigating the penetration rate of flupyrazofos into larvae body. On determining effective washing of $^{14}C$-flupyrazofos, the washing volume to recover over 98% of $^{14}C$-flupyrazofos was observed at three times (each time: 1 mL). To select a suitable solvent, the recovery rates of each solvent in 3rd instar larvae of DBM were above 98%, but the washing rates of acetone, hexane and ethyl-acetate were 85.1%, 67.2% and 68.4%, respectively. In the BAW larvae, although the recovery rates of each solvent were above 99%, the washing rates of acetone, hexane and ethyl-acetate were 83.5%, 65.9% and 71.7%, respectively. The $PT_{50}$ values of $^{14}C$-flupyrazofos were 0.731 h (44 min) in the DBM larva and 0.504 h (30 min) in the BAW larva. Radiocarbon in acetone washing (external fraction) decreased more quickly in the BAW larva than in the DBM larva, and amount of radiocarbon in larvae body increased more quickly with time in the DBM larva than in the BAW larva. In contrast, amount of radiocarbon in excreta increased more rapidly with time in the BAW larva than in the DBM larva.

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The Saemangeum: History and Controversy (새만금: 역사와 갈등)

  • Koh, Chul-Hwan;Ryu, Jong-Seong;Khim, Jong-Seong
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.13 no.4
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    • pp.327-334
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    • 2010
  • The paper describes the history and the evolution of the conflict of the Saemangeum reclamation project, focusing on the court trial processes. The Saemangeum project is the world largest coastal reclamation work, regarded as the most controversial environmental issue in the recent history of Korea. Due to the severe pollution found in Lake Sihwa in 1996, the Saemangeum project began to receive a large degree of public concern on the water quality of the proposed artificial freshwater lake. Unlike the Sihwa case, the Korean court system intervened to resolve the heated conflicts between stakeholders in the Saemangeum case. Based on the same set of facts, the Korean courts showed different perspectives on the economic feasibility, value of the ecosystem, land use, and water quality, which represents the limit of legal system to address complicated environmental problems. After the final judgment by the Supreme Court, 'the Special Act for the promotion of the Saemangeum reclamation project', was enacted with strong political support from local leaders and congressmen. A more developmental-oriented land use plan came out in 2009 based on this Act. The Saemangeum project walked along the different pathway from the Sihwa case. The area should be managed in sustainable manners to appropriately consider conservation and development for the prosperity of local residents and future generations.

Inclusive Impact Index "Triple I" for Assessing Ocean Utilization Technologies (해양이용기술 평가를 위한 포괄적 영향지수 "트리플 I")

  • Otsuka, Koji
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.15 no.2
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    • pp.118-125
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    • 2012
  • World population has increased rapidly following the industrial revolution, reaching 7 billion in 2012. Several forecasts estimate that this number will rise to about 8 billion in 2025. Improvements of living standards in developing nations have also raised resource and energy demands worldwide. In consequences, human beings have faced many global and urgent problems, such as global warming, water and food shortages, resource and energy crises, and so on. Many ocean utilization technologies for avoiding or reducing such big problems have been developed, for examples $CO_2$ ocean sequestration, seawater desalination, artificial upwelling, deepwater mining, and ocean energies. It is important, however, to assess such technologies from the viewpoints of sustainability and public acceptancy, since the aims of those technologies are to develop sustainable social systems rather than conventional ones based on fossil resources. Inclusive Marine Pressure Assessment and Classification Technology Research Committee (generally called IMPACT Research Committee) of Japan Society of Naval Architects and Ocean Engineers, has proposed Inclusive Impact Index "Triple I" as an indicator, which can predict both environmental sustainability and economical feasibility, in order to assess the ocean utilization technologies from the viewpoints of sustainability and public acceptancy. This index was considered by combining Ecological Footprint and Environmental Risk Assessment. The Ecological Footprint and the Environmental Risk Assessment are introduced in the first part of this paper. Then the concept and the structure of the Triple I are explained in the second part of this paper. Finally, the economy-ecology conversion factor in Triple I accounting is considered.

A Study on Public Perception of the Ex-suit Conservation Institution for Conserving Marine Animals: Case of the Korea National Maritime Museum (해양동물 보전을 위한 서식지외 보전기관에 대한 대중의 인식조사에 관한 연구 - 국립해양박물관사례를 중심으로)

  • Lee, Bomsok;Kwon, Suk-jae;Kim, Tae-goun
    • Journal of Navigation and Port Research
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    • v.43 no.6
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    • pp.475-482
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    • 2019
  • The increase in human use and activity in the oceans is leading to marine pollution and habitat destruction. As a result, in particular, marine animals with a long life cycle and small population are threatened with extinction. Thus, the Korean government designated 11 artificial habitats, such as aquariums and marine museums, as Ex-situ conservation institutions to preserve endangered marine life in 2010. However, studies on the significance and economic value of Ex-situ conservation institutions providing marine life conservation services have not been conducted. Thus, the purpose of this study was to estimate the public's quantitative support for the operation policy of Ex-situ conservation institutions, which is a management method for the protection and propagation of marine animals in Korea. To achieve this, the economic value of the marine animal conservation role of the National Maritime Museum was estimated, operated as an Ex-situ conservation institution for the preservation of green turtles in Korea. By using the representative non-market valuation method for public goods known as the contingent valuation method (CVM), the economic value of the Ex-situ conservation institution (National Maritime Museum) was estimated at approximately 41.8 billion won to a maximum of 78.1 billion won. The results of this study can be applied as basic data for marine animal management policymakers in establishing efficient management plans for endangered marine animals in Korea's coastal waters.

Construction and Experiment of an Educational Radar System (교육용 레이다 시스템의 제작 및 실험)

  • Ji, Younghun;Lee, Hoonyol
    • Korean Journal of Remote Sensing
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    • v.30 no.2
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    • pp.293-302
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    • 2014
  • Radar systems are used in remote sensing mainly as space-borne, airborne and ground-based Synthetic Aperture Radar (SAR), scatterometer and Doppler radar. Those systems are composed of expensive equipments and require expertise and professional skills for operation. Because of the limitation in getting experiences of the radar and SAR systems and its operations in ordinary universities and institutions, it is difficult to learn and exercise essential principles of radar hardware which are essential to understand and develop new application fields. To overcome those difficulties, in this paper, we present the construction and experiment of a low-cost educational radar system based on the blueprints of the MIT Cantenna system. The radar system was operated in three modes. Firstly, the velocity of moving cars was measured in Doppler radar mode. Secondly, the range of two moving targets were measured in radar mode with range resolution. Lastly, 2D images were constructed in GB-SAR mode to enhance the azimuth resolution. Additionally, we simulated the SAR raw data to compare Deramp-FFT and ${\omega}-k$ algorithms and to analyze the effect of antenna positional error for SAR focusing. We expect the system can be further developed into a light-weight SAR system onboard a unmanned aerial vehicle by improving the system with higher sampling frequency, I/Q acquisition, and more stable circuit design.

Evaluation on Strain Properties of 60 MPa Class High Strength Concrete according to the Coarse Aggregate Type and Elevated Temperature Condition (60MPa급 고강도 콘크리트의 굵은골재 종류와 고온상태에 따른 변형특성 평가)

  • Yoon, Min-Ho;Choe, Gyeong-Cheol;Lee, Tae-Gyu;Kim, Gyu-Yong
    • Journal of the Korea Concrete Institute
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    • v.26 no.3
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    • pp.247-254
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    • 2014
  • Strain properties of concrete member which acts as an important factor in the stability of the concrete structure in the event of fire, significantly affected the characteristics of the coarse aggregate, which accounts for most of the volume. For this reason, there are many studies on concrete using artificial lightweight aggregate which has smaller thermal expansion deformation than granite coarse aggregate. But the research is mostly limited on concrete using clay-based lightweight aggregate. Therefore, in this study, the high temperature compressive strength and elastic modulus, thermal strain and total strain, high temperature creep strain of concrete was evaluated. As a result, remaining rate of high-temperature strength of concrete using lightweight aggregate is higher than concrete with general aggregate and it is determined to be advantageous in terms of structural safety and ensuring high-temperature strength from the result of the total strain by loading and strain of thermal expansion. In addition, in the case of high-temperature creep, concrete shrinkage is increased by rising loading and temperature regardless of the type of aggregate, and concrete using lightweight aggregate shows bigger shrinkage than concrete with a granite-based aggregate. From this result, it is determined to require additional consideration on a high temperature creep strain in case of maintaining high temperature like as duration of a fire although concrete using light weight aggregate is an advantage in reducing the thermal expansion strain of the fire.

Analysis of Urban Park Nightscape based on the Design-Construction Process and Current Status - Focused on Yeouido Park - (도시공원 야간경관의 조성 과정과 실태 분석 - 여의도공원을 중심으로 -)

  • Kim, Hyun-Geun;Kim, Ah-Yeon
    • Journal of the Korean Institute of Landscape Architecture
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    • v.46 no.2
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    • pp.14-26
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    • 2018
  • Light has been an essential part of human life. The advancement of technology has changed cities' nightscape and night activities in a drastic way. Lighting has influenced the identity of a city while promoting a variety of civic nighttime cultural pursuits, yet lighting design has not been considered adequately in the field of landscape architecture. This study aims to analyze the current status of lighting in urban parks through interviews with professionals, literature and regulation reviews, analysis of design documents and a field survey focused on Yeouido Park in Seoul. The findings and improvement directions are as follows. First, it is necessary to develop a specific lighting design method in order to avoid a marginalized, passive approach such as light fixture installation. Second, the existing standards of illuminance by KS A 3011 regulating only horizontal illuminance has turned out not to evaluate the current nightscape of urban parks properly. Therefore the criteria and guideline for analysis and design for nightscape should be articulated. Third, there are no design or management strategies to consider the changing landscape of urban parks, which is necessary due to the changing characteristics of park ecosystems. Lastly, detailed guidelines for distinguished spaces in urban parks should be studied and suggested.