• 한국신재생에너지학회:학술대회논문집
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• 2005.11a
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• pp.363-372
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• 2005

최근 고유가상황 및 에너지소비가 증대되는 사회적 분위기와 환경적 변화에 힘입어 대체에너지기술개발에 대한 절실한 대책마련이 중요시 되고있다. 기후변화협약의 발효로 환경에너지에 대한 새로운 인식의 필요로 에너지체제의 변환이 촉구되어지고 있으며 이에 따른 환경친화적 에너지자원을 이용한 신 재생에너지개발에 대한 연구개발기술이 관심을 받고 있다. 현재 사용중인 화석연료는 환경오염 및 지구의 온난화 현상 등 심각한 공해문제를 야기시키고 있는 반면에 태양에너지와 같은 청정에너지의 개발은 환경오염방지와 친환경에너지자원의 활용이라는 점에서 관심이 대상이 되고 있고 특히, 우리나라의 경우 에너지수입 의존율이 97%로 높은 상황에서 국가에너지대책을 수립하고 해외수입에너지 의존율을 최소화시키기 위하여 가히 필수적인 상황이다. 따라서, 본 실증연구사업(태양열 이용 Hybrid냉난방시스템 실증연구)은 태양열 집열기에서 생산된 저온의 $20\sim30^{\circ}C$의 승온된 양질의 열원을 히트펌프 증발기 열원으로 이용 히트펌프의 압축동력이 상대적으로 작아져 기존 히트펌프 시스템에서의 성적계수(COP)를 높여 주는 효과를 기대할 수 있고, 특히 하절기 복사량이 많은 시기에는 $50\sim60^{\circ}C$ 정도로 승온되어진 중 고온수를 직접 온수탱크로 이동시켜 필요수요처에 공급함으로써 이에 따른 에너지절감효과를 기대할 수 있다. 구축된 태양열 이용 하이브리드(Hybrid)냉난방시스템은 계절별, 설비별 특성을 적절히 활용하여 연평균 집열기 효율은 70%수준으로 유지하면서, 계절별 성적계수는 '4'수준을 목표로 하여 추진되었으며, 그간, 태양열 이용 보급분야의 실용화는 주로 건물의 급탕용 온수생산의 수준에 머물렀으나 이 단계를 극복한 건물의 냉 난방 및 급탕을 위한 태양열 및 공기열원을 활용한 하이브리드(Hybrid)냉난방 시스템 구축하였다. 아울러, 태양열 이용 하이브리드 냉난방 히트펌프 시스템 실증 실험은 유가상승과 신재생에너지에 대한 국가적 분위기 고취로 어느때 보다도 개발기술의 상용화 및 실용화적 측면의 염두와 태양열 이용 Hybrid냉난방 시스템의 효율향상과 저가화를 통해 기술의 경제성과 신뢰성을 확보하여 태양열 이용 시스템의 보급활성화를 목표로 하고 있다.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.8 no.3
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• pp.171-176
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• 1975

Gae-bul, Urechis unicinctus, fresh or sun-dried has been esteemed as one of the most tasty sea foods in Korea. In this paper, the degradation of nucleotides and their related compounds in Gae-bul during sun drying was studied. The nucleotides and their related compounds were extracted with cold perchloric acid and their amounts were determined by anion exchange column chromatography. In fresh Gae-bul, the results showed that AMP was dominant and the content of ATP, ADP, AMP and inosine were 0.6, 3.5, 6.8 and $0.7{\mu}\;mole/g$ on dry base respectively while IMP was not detected. AMP tended to degrade slowly and ATP and ADP decreased rapidly while inosine ana hypoxanthine increased remarkably sun drying. In dried sample, the content of AMP was the highest, $5.6{\mu}\;mole/g$ on dry base, whereas ATP, ADP, inosine and hypoxanthine were lower.

• The Journal of the Korea Contents Association
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• v.11 no.8
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• pp.33-42
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• 2011

In this paper we designed and implemented a wireless communication circuit which can control the remote devices integrating RFID and ZigBee. This system unifies transmit part and receive part. And this system recognizes RFID tag data, then the recognized information is controlled by MCU, and transmitted to a remote device through the ZigBee. This is operated on TinyOS. If this system is applied to a entrance security system, it can permit/deny one's entrance as well as control the personal computer or other electronic devices. Our experiment shows the result of the recognized data transmission is very different according to a opened playground and a closed place. The data transmission time is stable in the indoor and the data transmission distance is long in the outdoor. We anticipate that our system be applied the various office oriented domains by connecting to the Wired LAN or the WLAN of IEEE 802.11x category.

• Journal of Bio-Environment Control
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• v.14 no.3
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• pp.212-217
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• 2005

This experiment was conducted to investigate the effect of water soluble fertilizer(WSF) and slow release fertilizer(SRF) on the growth of carnation(Dianthus caryophyllus 'Invitation') cultured in C-channel mat irrigation system. Plants grown in $0.8{\~}1.0\;g{\cdot}L^{-1}$ of WSF showed the highest quality, especially on fresh and dry weight of aerial part, leaf number, total leaf area, plant height, and branch number. All plants showed increase of growth rate around 60 days after treatment, although there was a different increase rate. Total leaf area decreased its increase rate after 90 days after treatment. Carnations supplied by WSF showed better growth and quality than SRF, and the optimum concentration range of WSF for pot-carnation was $0.8{\~}1.0\;g{\cdot}L^{-1}$ in C-channel mat irrigation system.

• Journal of the Korea institute for structural maintenance and inspection
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• v.15 no.4
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• pp.116-124
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• 2011

RC frames with unreinforced masonry infiledl walls are common in worldwide. Since infilled walls are normally considered as non-structural elements, their presence is often ignored by engineers. In this study, to improve the seismic performance of masonry walls, hexagonal block was developed and the influence of masonry infilled wall on the seismic performance of reinforced concrete(RC) frames that were designed in accordance with current code provisions without the consideration of earthquake loadings are investigated. Two 1/2 scale, single story, single bay, frame specimens were tested. The parameters investigated included that the strength of infilled wallls with respect to that of the lateral load history. The experimental results indicate that infilled walls can significantly improve the lateral stiffness and strength of RC frames. The lateral loads developed by the infilled frame specimen is higher than that of the bare frame. It also indicates that infilled walls can be potentially used to improve the performance of existing nonductile frames. For this purpose. methods should be developed to avoid irreparable damage and catastrophic failure.

• Journal of Korean Society for Geospatial Information Science
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• v.15 no.3
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• pp.59-67
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• 2007

This paper proposes potentialities of constructing the information system for earthquake hazard management which can manage and analyse earthquake risk and hazard systematically. The experimental results as well as architectural structure investment data for seismicity assessment are built in database and connected with GIS for assessing earthquake safety of building in urban area. For earthquake-resistant performance assessment, we collected and classified building structural data according to assessment criteria using building register, architectural map, digital map, and then complemented database with field survey data. We also suggest GIS-based information system can cope with and manage earthquake hazard effectively, as evaluating earthquake risk by performing detailed earthquake-resistant assessment and determining final assessment scores. The assessment should be processed quickly and accurately by integrating the earthquake hazard information management system with modularization of assessment procedure and method in the future.

• Journal of Korean Society of Steel Construction
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• v.23 no.2
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• pp.179-188
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• 2011

The performance-based design is highlighted as an alternative for the current design method, which cannot definitely specify the performance level that a building requires. Research on it is already in progress, however, in developed countries like the United States and Japan, to establish the basis for a performance-based design. Many studies on such design are also being conducted in South Korea, but South Korea still lags behind other countries in all-around technology. On the other hand, the column members, especially the lower external column, are affected by the variation of the axial force by overturning the moments in the case of lateral loads by earthquake. Varying the axial force can affect the time of local buckling and the ultimate behavior. Thus, in this study, the structural performance, such as the time of local buckling and the ultimate behavior, was analyzed through an experimental study on column members under varying axial force. The feasibility of a domestic study proposing a performance level with a story drift angle formed about a structural-performance-based steel structure design was also verified.

• Korean Journal of Weed Science
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• v.18 no.2
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• pp.122-127
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• 1998

This experiment was conducted to investigate the response of the fertilizer three factors on the growth of Alopeuclus aequalis Sobol. var. amurensis(Kom.) Ohwi. The growth of Alopeuclus aequalis Sobol. var. amurensis(Kom.) Ohwi. such as plant height, tiller number and dry matter production were vigorous on the plot fertilized with phosphate(P, NP, PK, NPK). The main effect of plant height elongation and dry matter production were significant for phosphate and nitrogen, and their interaction effect was recognized, too. Tiller growth and panicle number were mainly affected by phosphate. The growth of Alopeuclus aequalis Sobol. var. amurensis(Kom.) Ohwi. depended mostly on phosphate among the fertilizer three factors. The effect of nitrogen fertilizer was very different according to phosphate fertilizer treatment.

• Journal of the Korean Institute of Intelligent Systems
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• v.26 no.2
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• pp.153-159
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• 2016

In this paper, a mechanism of an omni-directional personal mobility which can drive diagonally is proposed. Mobility is a prerequisite involved in basic human life and activities. Personal mobility vehicle is a new mobility method which overcome the limits of automobiles. However, personal mobilities with four wheeled structure still have limitations. The proposed personal mobility vehicle can overcome the limitations of mobility because its rear wheels can be steered omni-directionally. In addition, the handicapped can drive it through a narrow road such as an alleyway or corridor and avoid obstacles on the traveling route. The proposed mechanism of personal mobility and the steering performance are tested by experiments, and the feasibility of diagonal driving is verified.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2018.10a
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• pp.57-57
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• 2018

관상용, 식용 및 약용으로도 이용되는 석죽목 석죽과의 여러해살이풀인 오랑캐장구채는 국내에서는 중부 이북지방의 유용 자생식물로 조경산업에의 이용가치가 크나, 이용성 증대 등을 위한 재배기술은 미흡하다. 지피식물용 재배조건의 구축을 위하여 2017년 7월 31일부터 10월 9일까지 약 10주간 본 연구를 수행하였다. 실험재료로 종자에서 육묘한 유묘를 사용하였으며, 유묘의 소질, 이식조건 및 재배관리에 대한 생육의 영향을 조사하였다. 유묘의 소질로는 162구 트레이에서 cell당 4립씩 파종하여 육묘된 유묘가 초장 및 건물중이 높았고, 특히 4립 파종구는 마디수를 제외한 생육량이 다른 처리구에 비해 유의적으로 큰 차이가 있었다. 경제성을 고려할 때, 상토는 혼합비료(N-P-K) $300-200-200mg{\cdot}L^{-1}$가 첨가된 마사토:피트모스(3:1) 혼용토를 충진한 처리구가 효과적이었다. 또한, 코트비료의 기비처리는 포트당 20알 처리구에서 지하부 생체중이 무거웠으나, 엽면적 등 다른 생육량을 고려할 때 기비하지 않은 처리가 효과적이다. 재배관리에 있어서 차광처리는 습기 등의 환경에 약한 유묘의 특성상 차광하지 않고 배치하는 것이 모든 생육량이 높았다. 이식 후에는 추비처리를 하는 것이 효과적이며, 추비농도는 엽수 등을 고려할 때 $500mg{\cdot}L^{-1}$ hyponex이 적합하였다.