Pultruded fiber reinforced polymeric plastic (PFRP) has many advantages such as high corrosion resistance, high specific stength/stiffness, light weight, etc. Pultrusion is a manufacturing process for producing continuous lengths of reinforced polymeric structural shapes with constant cross-section. The mechanical property of PFRP is usually regarded as an orthotropic material. The pultruded structural shapes are usually composed of thin-walled plate element. Because the composite material has relatively low elastic moduli, the design of pultruded compression members may not be governed by the material strength limit state but by the stability limit state such as the local buckling. Therefore, the stability limit state must be checked to design pultruded thin-walled compression members. In this paper, we present the analytical study results of elastic buckling strength of PFRP orthotropic plates with different fiber volume ratios. The local buckling analysis of pultruded compression members was conducted for various composite materials using the closed-form solution. From the study it was found that if E11/E22 is increased then the plate buckling coefficient, hence the plate buckling strength, is decreased.

In the water supply pipeline system polyethylene (PE), polyvinyl chloride (PVC), and ductile cast iron pipe are mostly used. However, they have some problems such as reduced durability due to material degradation, defects in connections, the pipelines breakage, and lack of continuous maintenance. Recently, research on durable and outstanding corrosion resistance glass fiber reinforced polymer plastic (GFRP) pipe is being actively conducted. GFRP is classified into the flexible pipe and when soil pressure and live load act on buried GFRP pipe, the load acting on the pipe is transferred to the surrounding soil. So, pipe will support the load with the surrounding soil. In this paper, to apply GFRP pipe for the water supply pipeline system, the structural reliability of GFRP water supply pipe buried underground should be investigated by examining the mechanical properties of GFRP pipe as well as the soundness of the pipe under buried state. The field test of buried pipe is conducted and the results are analyzed and discussed.

Pipe line for the water supply and/or drainage is one of the most important life lines which is usually suffered from the damage due to exterior load induced deformation and due to the lack of support resistance provided by the surrounding soil. GFRP (Glass Fiber Reinforced Polymer Plastic) pipes are generally thinner, lighter, but stronger than the existing concrete or steel pipes, and it is excellent in stiffness/strength per unit weight. In this study, we present the result of field test for buried RPMP (Reinforced Polymer Mortar Pipe) and RTRP (Reinforced Thermosetting Resin Pipe) pipes with 2,400mm diameter. The vertical and horizontal ring deflections are measured for 387 days. The ring deflection of RPMP and RTRP measured by the field test is compared with the ring deflection limitation (5%) according to ASTM D 2412.

환경영향지수(EIQ)는 사용자가 선택한 농약이 환경과 건강에 미치는 영향을 스스로 평가 가능하도록 함으로써, 농약 선택시 더 나은 의사결정을 내릴 수 있도록 농약위해성 지표를 제시하는 모델이다. 본 연구는 제주도 감귤생산 방제력 분석을 통해 농가가 선택한 약제 중 90%이상 선호하는 성분에 대한 환경영향지수(EIQ) 평가를 통해 작업자, 소비자, 생태계 등 여러 분야에 대한 농약 위험성 평가를 하였다. 농작업자에 대한 영향에서 chlorpyrifos 성분의 EIQ 지수값이 71.7로 가장 높았으며, 이는 EIQ 평균값(33)보다 크케 상회하였 고, 소비자에 대한 영향은 clothianidin와 imdacloprid의 EIQ 지수값이 공동으로 50으로 평균값(12.7)보다 높게 나와 소비자에 대한 안전을 위해서는 평균값 이하의 영향을 주는 성분으로 약제를 살포하는 것이 좋을 것으로 생각되었다. 생태계에 대한 영향은 평균값(58.5)보다 큰 성분이 전체 성분에서 42.5%를 차지하여 농가에서 사용하는 농약의 40% 이상이 생태계에 대한 영향이 클 것으로 생각된다.

Surface-active substances in defatted rapeseed cake were obtained using a supercritical fluid extraction method. Then, it was purified by removing sinapine in the extract through a series of steps using a mixed solvent: diethyl ether and ethyl acetate (1:1, v/v). Emulsifying properties of purified surface-active substances were investigated, including fat globule size, zeta potentials and creaming stability and its antioxidant activity in emulsion systems were also studied by peroxide value and 1H-NMR spectrum. It was found that fat globules in emulsions with purified surface-active substances were much smaller than ones with the unpurified. In addition, as pH of the emulsion lowered and with increasing NaCl concentration in the emulsion, they were observed to increase, which led to worse creaming stability. These properties were reflected in changes of zeta potentials of emulsions. The oxidative stability was better in emulsions with purified surface-active substances than ones with Tween 20 or commercial lecithin, possibly resulted from the existence of sinapic acid in the extract. It was concluded that purified surface-active substances from defatted rapeseed cake could be simultaneously used as emulsifier and antioxidant agent in emulsion system.

This study was carried out to assess the carbon budget of two urban parks and one natural park and to prepare the plan for improving the ecological functions of the park including carbon sink. Net Ecosystem Production (NEP) of those study sites was calculated from the relationship between Net Primary Production (NPP) and soil respiration of each study site. To understand carbon budget of the whole area designated as the park, carbon budget of the urban park was analyzed by classifying the vegetated and the non-vegetated zones. NEP of the Nohae and the Sanggye parks calculated by reflecting areal size that the non-vegetated zones occupy were shown in - 1.0 and 0.6 ton C ha-1 yr-1, respectively. On the other hand, NEP of Mt. Bulam natural park as a reference site was in 2.3 ton C ha-1 yr-1. Based on the result, the Nohae park was assessed as carbon source rather than carbon sink. On the other hand, the Sanggye park was classified as carbon sink but the role was poor compared with natural park. The result is, first of all, due to lower NPP of the vegetation introduced for the parks compared with natural vegetation. The other reason is due to wide arrangement of non-vegetated zone. To solve those problems and thereby to create the urban park with high ecological quality, selection of plant species suitable for the ecological characteristic of the park, their arrangement imitated natural vegetation, and ecological zoning were recommended.

본 연구의 목적은 가까운 미래의 선박운동정보를 이용하는 피드포워드 제어알고리즘과 FPSO 운동 수치 시뮬레이션 모델을 개발하고 시뮬레이션을 통하여 제어알고리즘의 성능을 검증하는 것이다. 본 논문에서는 조류, 바람, 파력 등의 환경하중에 의하여 발생한 선체운동의 미래 예측치를 활용한 피드포워드 제어력을 추가적으로 가지는 Dynamic Positioning System에 대하여 연구한다. 먼저, 조류력, 풍력 및 파력에 대한 수학모델을 선정하여 환경하중에서의 선체운동을 계산하고, 현재의 선체운동 값과 Brown 지수평활 예측모형을 활용하여 미래 선체운동 값을 예측하였다. 또한 위치 유지와 Heading angle 제어를 위한 제어력을 PID(Proportional-Integral-Derivative)이론을 이용하여 결정한 피드백 제어기와 미래 선체운동 값을 이용하여 결정한 피드포워드 제어기로 구성하였다. 그리고 각 Thruster에 요구되는 추력은 라그랑지승수법을 활용하여 분배하였다. 마지막으로 FPSO(Floating Production Storage and Offloading)의 운동과 Dynamic Positioning System에 대한 시뮬레이션 모델을 구축하여 선박의 위치 및 Heading angle 제어에 관한 시뮬레이션을 수행하여 제안하는 피드백 제어기와 피드포워드 제어기를 동시에 가지는 제어시스템의 성능을 평가하였다. 본 연구의 결과, 피드백 및 피드 포워드 제어기가 적용된 DPS 제어시스템이 기존의 피드백 제어기보다 위치유지 및 헤딩각 유지 능력에서 개선되었고 각 Thruster에 요구되는 평균 제어력 및 최대 제어력의 크기도 감소함을 보였다. 이에 따라 DPS에 요구되는 동력 감축과 Azimuth Thruster 용량의 감소로 인하여 비용 절감의 효과를 기대할 수 있다.

In this study, we investigated the concentrations of PM10 and CO2 in public transportation vehicles (express bus, train, KTX, and subway) reported by previous indoor air quality (IAQ) surveys carried out from 2005 to 2013 in Korea. The number of valid data for PM10 was 566 and for CO2 was 579, and all data were classified according to whether it was collected during rush-hour or non rush-hour. PM10 and CO2 concentrations in subway cabin during the rush-hour were 1.3 and 1.45 times higher, respectively, than those of non rush-hour (p<0.05) in terms of geometric mean value. PM10 and CO2 concentration of express bus and train during the rush-hour also were 1.23 times higher than those of non rush-hour with relatively weak correlations (p=0.246). Among all PM10 concentrations, 16.9% and 3.8% of PM10 concentrations exceeded the IAQ guidelines (200 μg/m3 for non-rush hour and 250 μg/m3 for rush-hour), respectively. In terms of CO2 concentrations, 10.5% and 3.0% of them exceeded the IAQ guidelines (2,500 ppm for non rush-hour and 3,000 ppm for rush-hour), respectively. As a result, concentrations of PM10 and CO2 were estimated to be dominantly influenced by the operation characteristics of public transportation, such as degree of congestion and type of vehicle. In order to improve the IAQ of public transportation vehicles, specific air purification and ventilation systems are needed, depending on the characteristics of public transportation vehicles.

The concern of fine particle (PM2.5) management of outdoor environments has been increasing due to its exposure and related health effects in Korea. As a result, PM2.5 standard in atmosphere environment was regulated in 2015. On the other hand, indoor PM2.5 standard has been required because most people spent their times in indoor environments. In this study, we measured the PM2.5 and PM10 concentrations both indoor and outdoor environments of public-use facilities such as underground stations, underground shopping centers, and nurseries for 24 hour with filter-weighing method in Seoul and Daegu. Measurement duration was from March to April in 2014 during the Asian dust period. At all measurements, indoor to outdoor (I/O) concentration ratios exceeded 1 except 1 day nursery in Daegu in spite of Asian dust period. The ratios of PM2.5 to PM10 concentrations ranged from 0.63 to 0.75 in indoor environments, and from 0.63 to 0.82 in outdoor, indicating that PM2.5 should be carefully managed in indoor environments as well as outdoor atmosphere.

In this paper, we present the result of analytical investigation pertaining to the structural behavior of steel-concrete composite plate girder with arch-type web stiffener. In the arch-type web stiffener located in the compression side of web, infill concrete is cast to strengthen the arch-type stiffener and also to exert resisting force against compression force. This type of composite steel-concrete plate girder bridge is built and is in service. To understand the behavior thoroughly, analytical parametric study was conducted by using the finite element method. As a result it was found that the effect of arch-type stiffener with infill concrete is considerable for the design of such type composite girder bridge.

In this study, the process of sinapine removal from surface-active substances extracted from defatted rapeseed cake was established by using a mixed organic solvent system (diethylether:ethyl acetate = 1:1, v/v). The emulsifying properties of the purified surface-active substances were investigated. Thin layer chromatogram showed that sinapine was removed and purified surface-active substances were found to have better emulsifying properties compared to a non-purified one or commercial soy lecithin. As for interfacial tension data, purified surface-active substances showed values lower (10-1 wt%: 3.20±0.57 mN/m) than the non-purified ones (10-1 wt%: 14.16±0.27 mN/m). In addition, we found that fat globule size in emulsions with purified surface-active substances was much smaller than in emulsions with non-purified substances or commercial soy lecithin. These results could be attributable to the increased amount of phospholipids in purified substances following sinapine-removal.

표고(Lentinula edodes)는 우리나라의 대표적인 임산자원의 하나로, 식용 및 약용으로 사용한 기록이 오래전부 터 존재해 왔다. 자생표고와 달리 재배 표고의 경우 품종에 따른 기원이 명확하지 않아, 수출 및 가공상품 개 발에 어려움이 있다. 이러한 문제점 해결의 일환으로 국내에서 개발된 표고 4품종(‘산림2호’, ‘산림4호’, ‘산림 5호’, ‘산림7호’)의 일반성분, 유리당, β-glucan, ergosterol 함량을 분석하였다. 일반성분 분석결과 수분 함량은 5.44~6.80%로 나타났으며, 회분 함량은 3.34~5.08%로 나타났다. 조단백질 함량은 12.94~21.07%로 나타났으며, 조지방 함량은 1.42~2.24%로 나타났다. 조섬유 함량은 3.27~4.01%로 나타났고, 가용성 무질소물 함량은 54.19~64.78%로 나타났다. 유리당 분석결과 버섯에 함유된 유리당 중 가장 강한 항산화 기능이 있다고 알려 진 fucose는 산림7호 품종에서만 0.34%의 함량이 나타났으며, 총 유리당 함량도 산림7호 품종이 14.38%로 가 장 높게 나타났다. β-glucan 함량은 ‘산림2호’, ‘산림4호’, ‘산림7호’ 품종은 33.09~35.41%로 큰 차이가 없었으 나 ‘산림5호’ 품종은 28.49%로 낮게 나타났다. Ergosterol 함량은 ‘산림2호’ 16.62 mg%, ‘산림4호’ 143.62 mg% 의 순으로 나타났다.

UPOV 등 국제적인 품종에 대한 보호협약이 연이어 타결되고 있는 상황에서 우리나라 기후와 환경에 적합한 표고(Lentinula edodes) 품종 개발이 시도되고 있다. 개발된 품종들의 식품학적 이용을 위한 과학적 자료 확보 를 위하여 국내에서 개발된 표고 4품종(‘천백고’, ‘다산향’, ‘청장1호’, ‘풍년고’)의 일반성분, 유리당, β-glucan, ergosterol 함량을 분석하였다. 일반성분 분석결과 수분 함량은 6.14~6.47%로 나타났으며, 회분 함량은 1.06~3.95%로 나타났다. 조단백질 함량은 11.74~19.32%로 나타났으며, 조지방 함량은 1.54~2.56%로 나타났다. 조섬유 함량은 2.70~4.80%로 나타났고, 가용성 무질소물 함량은 55.16~72.78%로 나타났다. 유리당 분석결과 버섯에 함유된 유리당 중 가장 강한 항산화 기능이 있다고 알려진 fucose는 ‘풍년고’ 품종에서만 0.18%의 함 량이 나타났으며, 총 유리당 함량도 ‘풍년고’ 품종이 13.77%로 가장 높게 나타났다.. β-glucan 함량은 ‘다산 향’, ‘천장1호’, ‘풍년고’ 품종은 30.05~31.97%로 큰 차이가 없었으나 ‘천백고’ 품종은 26.04%로 약간 낮게 나 타났다. Ergosterol 함량은 ‘천백고’ 188.59 mg%, ‘다산향’ 157.78 mg%의 순으로 나타났다.