검색결과

검색조건
좁혀보기
검색필터
결과 내 재검색

간행물

    분야

      발행연도

      -

        검색결과 64

        30.
        1999.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This review discussed the properties of biological factors affecting the function of phosphorus (P) sink of wetlands, and proposed the applicability of microbes, especially periphyton in phosphorus removal. Microbes have a large potential in natural purification of water, because they have fast growth rates and outcompete macrophytes in taking up P. The degree of P uptake by microbes, especially periphyton appears largely to depend on P and light availability and their biomass. As long as there is sufficient light, periphyton can accrue biomass in the system, assuming losses from herbivory and disturbance are not too great. This large periphyton biomass can reduce P concentrations in the water column via uptake and adsorption, and thereby being able to reduce algal blooms. This idea can be applicable to ameliorate water quality by introducing constructed wetlands and shallow ponds in the incoming region of rivers or lakes. The future studies are required to accumulate data on P cycling between microbes and environmental parameters in wetlands.
        4,500원
        32.
        1992.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        역삼투공정과 비교하여 효율적인 농축공정인 OSRO공정에 의한 농축공정을 개발하여 에탄올 농축에 적용한 결과 역삼투공정에 비하여 높은 에탄올 농축효과를 얻었으며, 에탄올 분리효과가 뛰어난 OSRO용 막의 배발 및 농축장치를 다단으로 사용할 경우 산업화가 가능하다는 결과를 얻었다. 역삼투공정에 대한 OSRO공정의 농축도차(DCOSRODCRO)는 전 실험범위에서 0보다 큰 값을 보이므로 에탄올 농축에 있어서 OSRO공정이 역삼투공정에 비해 효과적임을 확인하였다. OSRO공정에서 공급용액의 농도 및 부피유속이 감소하고 적용압력이 증가하는 것이 조업조건으로서 유리하였다. OSRO공정에 대한 이론식의 수치모사에 의한 해석적 결과로부터 단수가 증가할 수록 역삼투공정 및 OSRO공정의 농축도값은 커짐을 알 수 있었고, 같은 단내에서는 적용압력이 상승함에 따라 농축도값은 증가하는 경향을 보였다. 또한 수치모사에 의한 농축도 이론치는 실험치와 약 15% 이내에서 일치하였다. 농축도는 적용압려과 osmotic sink solution의 부피유속에는 비례하여 증가하며, 공급액 농도와 부피유속에 대해서는 감소함을 알 수 있었으며, 본 연구에서는 실험범위외의 수치모사에 의한 농축도 이론치도 제시하였다.
        4,900원
        33.
        2019.04 서비스 종료(열람 제한)
        As the road sink phenomenon occurred continuously at the center of seoul in 2014. The road sink phenomenon was emerged as a social big issue in korea. So far, government, municipalities and related experts have been making a lot of efforts to prevent road sink accident, but it is still happening all over the country. Therefore, In this study aims to present the restoration action procedures and checklist items that can be used by government officials in order to recover quickly in the event of a road sink.
        34.
        2017.09 서비스 종료(열람 제한)
        As the road sink phenomenon occurred at the center of Seoul area in 2014, the road sink phenomenon was emerged as a social issue in Korea. Even so far, governments, municipalities and related experts have been making a lot of efforts to prevent road sink, but it is still happening all over the country. The most effective way to prevent road sink phenomenon is judged as a policy alternative. Therefore, In this study, we analyzed the representative policy cases in the government for providing the behavioral procedures and checklists to be use person in charge.
        35.
        2016.04 서비스 종료(열람 제한)
        A new research project entitled 「Development of Evaluation and Analysis Technologies for Road Sink」 was initiated last year under the sponsorship of Korea Agency for Infrastructure Technology Advancement and Ministry of Land, Infrastructure and Transport. In this article, outlines of this project is briefly introduced including research goal, scope, current major activities, etc.
        36.
        2013.06 KCI 등재 서비스 종료(열람 제한)
        고온발생시 과연 sink가 적은 것이 등숙에 유리한지를 검토하기 위해,1. 등숙기간 동안 적온인22℃와 고온인 27℃ 에 처리한후 천립중 감소율과 현미완전미감소율 비교하여 국내품종들 중에서 고온등숙에 강한 품종(동안벼)과 약한품종(일품벼)를 선발하였다. 2. 고온에 대한 두 품종의 차이를 이삭형태 관점에서 비교한 결과 동안벼와 일품벼는 약세영화와 강세영화간의 비율에서는 큰 차이가 없었으나 총영화수에서 일품벼가 더 많았다. 따라서, 많은 영화수를 고온에서의 천립중 감소의 원인으로 가정하여 영화수 조절을 통한등숙특성 개선을 시도하였다.3. 이를 위해 약세영화를 제거하여 영화수를 조절한 결과천립중은 개선이 가능한 것으로 생각되었으나 현미완전미율에서는 효과가 없었다.4. 따라서, 천립중은 동화산물의 공급균형과 관련된 문제로 추정되는 반면 현미완전미율은 영화 내부의 전분축적과 관련된 대사이상으로 생각되며, 고온 등숙 문제를 해결하기 위해 영화수를 조절하는 것은 한계가 있을 것으로 생각된다.
        37.
        2011.08 KCI 등재 서비스 종료(열람 제한)
        Robots have been used in many fields due to its performance improvement and variety of its functionality, to the extent which robots can replace human tasks. Individual feature and better performance of robots are expected and required to be created. As their performances and functions have increased, systems have gotten more complicated. Multi mobile robots can perform complex tasks with simple robot system and algorithm. But multi mobile robots face much more complex driving problem than singular driving. To solve the problem, in this study, driving algorithm based on the energy method is applied to the individual robot in a group. This makes a cluster be in a formation automatically and suggests a cluster the automatic driving method so that they stably arrive at the target. The energy method mentioned above is applying attractive force and repulsive force to a special target, other robots or obstacles. This creates the potential energy, and the robot is controlled to drive in the direction of decreasing energy, which basically satisfies lyapunov function. Through this method, a cluster robot is able to create a formation and stably arrives at its target.
        38.
        2010.04 KCI 등재 서비스 종료(열람 제한)
        Climate warming has the potential to deteriorate grain yield and quality of rice (Oryza sativa L.), offsetting the stimulative effects of elevating CO2. To know how the change in sink-source balances by reducing sink-size (RSS) may affect grain yield and quality of rice grown under various climate change scenarios, we conducted a temperature gradient chamber experiment with/without CO2 fumigation systems which were established in paddy field. Rice crops (cv. Ilmybyeo) were exposed to either ambient (396ppmV) or elevated CO2 of 673ppmV in three levels of air temperature [(Ta), local ambient Ta (24.8℃), 1.3℃ and 2.4℃ above ambient Ta] over whole seasons. Thus, the experiment was a 2×3 factorial design with three replicate plots of each CO2×Ta combination. At flowering, for two hills from each combination treatment total thirty (10 per each top, middle and basal parts of panicle) spikelets per panicle were removed with order of panicle appearance by scissors. This corresponded to a 25% reduction of total sink-size per hill. In ambient Ta and CO2 , grain yield decreased with RSS by 23.4%, approximately mirroring the reduced sink-size. With rising Ta, however, the yield reduction by RSS was significantly mitigated (-5.6% in 1.3℃ above ambient Ta), and the yield rather increased with RSS by 9.3% in 2.4℃ above ambient Ta. This was due primarily to the increased single grain mass with RSS. A similar response fashion of grain mass and yield with RSS to Ta was found in elevated CO2, but not CO2×Ta interaction. For brown rice, the fraction of normal rice was linearly reduced with rising Ta, ranging from 78.5~79.2% in local ambient Ta to 48.2~55.5% in 2.4℃ above ambient Ta over CO2 treatments. However, this deteriorative effect of rising Ta was significantly alleviated with RSS; the fractions of normal rice were a 81.9~84.1%, 75.9~77.2% and 64.0~66.3% in local ambient Ta, 1.3℃ and 2.4℃ above ambient Ta, respectively. The alleviative effect of RSS on rice quality was due mainly to the reduced immature rice, and was more conspicuous as Ta rises. These results suggest that current rice cultivars in Korea, at least cultivars tested in this experiment, will likely to be prone to source-limitation in the future projected warming with elevating CO2, and thereby will be needed a cultivar having either a greater source ability or a less sink size compared with current cultivars, in order to ensure a rice quality in the future warming conditions.
        39.
        2009.03 KCI 등재 서비스 종료(열람 제한)
        2002년도에는 sink는 변화를 주지 않고 엽제거에 의해 source의 크기를, 2007년에는 파종기, 질소시비량 및 재식밀도를 달리하여 sink와 source의 크기를 조절한 후 이들이 종실중 및 종실질소함량의 형성과정에 미치는 영향을 분석하고자 하였던 바 이에 대한 결과는 다음과 같다. 1. 엽제거를 통해 source의 크기를 직접적으로 조절하였을 때는 출수전 엽에 저장되었던 동화산물과 질소에 직접적으로 영향을 주어 해석에 혼란을 주었으며, 파종기, 질소시비량 및 재식밀도 조정과 출수기 솎아내기를 통해 sink와 source의 크기를 조절할 경우에는 다양한 크기의 sink와 source를 얻었지만 모든 sink와 source 관련 형질이 서로 매우 밀접하게 관련되어 있어 등숙기간 중 종실중 및 종실질소함량에 미치는 sink 또는 source 관련형질의 개별효과를 분석하기는 어려웠다 2. source가 클수록 종실중과 GWP 는 증가하는 경향이었으나, GWT 는 감소하는 경향이었으며, sink는 source와는 반대의 경향을 보였다. 또한 source 관련형질중 지상부 총건물중이 종실중과 그 구성인자에 대한 영향력이 가장 컸으며, 구성인자 중에서는 GWP 가 GWT 에 비해 종실중에 큰 영향을 주는 것으로 나타났다. 3. source가 클수록 종실질소함량과 GNS 가 많은 경향이었으나, GNT 는 감소하는 경향이었으며, sink는 source와는 반대의 경향을 보였다. 또한 source 관련형질중 지상부 총질소함량이 GN에 대한 영향이 가장 컸으며, 구성인자 중에서는 GNS 가 GNT 에 비해 종실질소함량에 큰 영향을 주었으나 종실중과는 달리 GNT 가 종실질소함량을 차지하는 비중이 비교적 컸다. 4. 등숙기간 중 종실 질소는 토양으로부터 먼저 공급되거나 적어도 잎 또는 줄기로부터의 전류와 토양으로부터의 공급이 동시에 이루어지는 것으로 나타났다.
        40.
        2006.09 KCI 등재 서비스 종료(열람 제한)
        This study was conducted to investigate the influence of drought stress during the pod developing and seed filling stage on source-sink relationships of soybean (Glycine max). Drought treatments were imposed by withholding water at the full-pod stage, 19 days after flowering, and then limited watering was relieved at 15 days after the initiation of drought treatment. Soybean seed yield was reduced by 39% mainly due to decreased pod number under drought stress, but the 100-seed weight was relatively less reduced. In spite of the 15-day drought during the full-pod stage, soybean produced good seeds showing similar l00-seed weight, protein, starch and soluble sugar content to those from the well-watered. Although drought during the full-pod stage caused source limitations; i.e. accelerated leaf senescence and reduced leaf soluble sugars, it did not cause limitations of other source characteristics such as SGR and leaf starch level. This is because the reduction in size of sinks, such as pod and seed abortions compensated for source limitations, resulting in balanced source-sink as expressed by LAR and the ratio of leaf area to seed dry weight. Drought stress during the pod developing and seed filling stage did not disrupt the source-sink balance
        1 2 3 4