• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2008년도 추계 학술논문 발표대회
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• pp.227-233
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• 2008

Porous concrete has large continuous voids of 20-30 % by volume, and this concrete is attractive as environmental material in Japan i.e. permeable road pavement, river bank protection with vegetation and green roof system which influence thermal environment. It is necessary to confirm the frost resistance when constructing porous concrete structure in cold region. However applicable test method and evaluation criterion of porous concrete has not defined yet. Therefore, the object of this study is to investigate the frost resistance of porous concrete and this investigation attempts to address this concern by comparing 4 kinds of specified freezing and thawing tests methods (JIS A1148 procedure A/B and RILEM CIF/CDF test) in consideration of actual environment. RILEM freeze-thaw tests are different from JIS A1148 freeze-thaw tests, which are widely adopted for evaluating the frost resistance of conventional concrete in Japan, in water absorption, cooling rate, length of freezing and thawing period, and number of freezing and thawing cycles. RILEM CIF test measures internal damage and is primarily applicable for pure frost attack. CDF test is appropriate for freeze-thaw and de-icing salt attack. JIS A1148 procedure A/B showed extremely low frost resistance of porous concrete if the large continuous voids were filled with water and the ice expansion in the large continuous voids set in during cooling. Frost resistance of porous concrete was improved by mixing coarse aggregate (G7) which particle size is smaller and fine aggregate in JIS freezing and thawing tests. RILEM CIF/CDF test showed that freeze-thaw and de-icing resistance of porous concrete was seems to be superior in that of conventional concrete.

• 한국작물학회지
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• 제54권4호
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• pp.452-457
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• 2009

본 시험은 벼가 저온 피해를 받았을 때 수확 전에 쌀 수량 및 품질변화를 예측하여 쌀 수급계획 수립 및 벼 안정생산기술 개발의 기초자료를 제공하고자, 2007년 국립식량과학원 춘천출장소 냉해검정 포장에서 오대벼를 이용하여 수행하였다. 냉해를 유발하기 위해서 수온이 $17^{\circ}C$인 물을 유수형성기부터 출수기까지 관개 처리하였다. 수확은 임실률에 따라서 하였고, 품질분석 항목은 등숙률, 제현률, 현미천립중, 단백질함량 등을 조사하였다. 품질특성분석은 임실률 변화에 따라서 각 항목별로 하였다. 1. 임실률에 따른 등숙률은 y=1.0444x-7.6597$(R^2=0.9874^{**})$의 관계가 있어서 임실률이 1% 증가하면 등숙비율은 1.0444% 증가하여, 임실률이 40~50%일 때 등숙비율은 34.1~44.6%, 임실률 60~70%일 때 등숙비율은 55~65.4%, 임실률 80~90%일 때 등숙비율은 75.9~86.3%이었다. 2. 완전미율은 임실률 변화에 따라 회귀분석을 하면 y=-0.2306x+104.32$(R^2=0.634^*)$로 임실률과 부의 관계가 있어서, 저온 피해를 받았을 때 임실률에 따른 완전미율 예측이 가능하여 임실율이 40%일 때 완전미율은 95.1%, 임실률이 50~60%일 때 완전미율은 92.8~90.5%, 임실률이 70~80%일 때 완전미율은 88.2~85.9%, 임실률이 90%일 때 완전미율은 83.6%로 임실률이 높으면 완전미율은 낮았다. 3. 단백질함량는 임실률에 따라서 y=-0.046x+10.875$(R^2=0.6973^*)$의 관계가 있어서 임실률이 증가하면 감소하는 경향으로 임실률이 40~50%일 때 단백질함량은 9.0~8.6%, 임실률 60~70%일 때 단백질함량은 8.1~7.7%, 임실률 80~90%일 때 단백질함량은 7.2~6.7%이었다. 이와 같이 저온피해 정도가 커서 임실립수가 적어지면 단백질함량은 높아져서 쌀 품질을 저하시킨다. 4. 저온피해를 받은 벼의 쌀은 자연구보다 아밀로스함량은 높고, 현미천립중, 정현비율, 현백비율은 낮으며, 백미의 백도는 비슷하였으나, 임실률에 따른 뚜렷한 경향은 없었다.

• 한국작물학회지
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• 제31권3호
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• pp.326-335
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• 1986

본 시험을 생식생장기 냉수관개가 벼의 Source와 Sink 관련형질 및 양분흡수에 미치는 시비반응을 구명한 것으로 그 결과를 요약하면 다음과 같다. 1. 질소의 과용은 생육 및 수량을 감퇴시켰으나 인산, 가리, 규산의 증비로 생육량의 증대, 영화착생량과 등숙비율 향상에 유리하였다. 2. 영화의 착생수, 기경과 영화의 퇴화율, 불임율은 인산, 가리, 규산의 증비로 그 피해를 경감시킬 수 있었으며 특히 규산의 증비효과가 현저하였고 지경당 개화는 1차 지경보다 2차 지경에 착생한 영화수에 크게 영향을 받았다. 3. 미립 및 등미의 발생량과 수량과는 부의 상관관계가 있었으며 인산, 가리, 규산의 증비는 추액및 서미의 발생억제와 수량증가에 효과적이었다. 4. 질소의 증비는 엽신. 지경, 영곡의 전질소함량을 높이고 인산, 가리, 규산의 흡수를 저해시켰으나 인산, 가리, 규산의 증비는 질소의 과잉흡수억제 및 인산, 가리, 규산의 흡수를 증가시켰고 지경의 무기성분함양은 엽신보다는 적었다. 5. 엽신. 지경, 영곡의 무기성분함량의 상호관련성은 지경의 무기성분은 엽신의 무기성분함양에 영향을 받고 지경은 다시 영곡의 무기성분조성에 영향을 미치고 있음을 알 수 있었다. 6. Source 와 Sink 관련형질에 미치는 엽신, 지경, 영곡의 무기성분반응을 보면 지경과 영화의 퇴화율, 불임율, 등숙비율, 수량 모두 엽신, 영곡보다 지경의 무기성분함양에 크게 영향을 받았다. 이로 보아 지경은 단순한 양분이동의 통로기능만을 갖는 것이 아니라 종실의 물질집적에 중요한 생리적 기능을 가지는 기관임을 알 수 있었다.

• 농촌계획
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• 제29권1호
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• pp.69-79
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• 2023

Uiseong-gun, Gyeongsangbuk-do, one of the representative small rain regions, has developed a traditional irrigation farming system while overcoming and adapting to unfavorable agricultural environments from the days of the ancient nation of Jomunguk to the present. In 2018, its value was recognized and designated as Nationally Important Agricultural Heritage System No. 10. This study was conducted with the purpose of examining the characteristics of the traditional irrigation farming system in Uiseong from the viewpoints of irrigation facilities, irrigation communities, and agricultural activities. The research results are as follows. Uiseong-gun has been expanding irrigation facilities for agriculture since long ago, and it has been investigated that a total of 6,227 irrigation facilities are currently distributed along the Wicheon water system that crosses Uiseong-gun from east to west. Irrigation facilities appear differently depending on the topography. The irrigation facility has a 'su-tong' as an irrigation passage and a corkscrew structure 'mot-tchong' as a water quantity control device, so the amount of water was adjusted as needed. Through this facility, surface water with warmer temperature is supplied to the farmland to prevent cold damage to crops. Uiseong has developed activities to organize irrigation communities in one village or several villages to secure agricultural water from an early age. Currently, this tradition continues, and a total of 213 irrigation communities manage 375 irrigation facilities (6.0% of all irrigation facilities). Through this organization, called Mong-ri-gye, water for agriculture is obtained, managed, and distributed equitably. In order to increase agricultural production, Uiseong implemented double cropping by converting rice fields and fields. In the case of Mt. Geumseong, double cropping of rice and barley was mainly carried out until the 1970s, but since the 1980s, double cropping of rice and garlic has been implemented with higher income. One of the unique features of the agricultural system of this region is the spectacular landscape that changes simultaneously from field to rice field in spring and from rice field to field in autumn.

• 한국구조물진단유지관리공학회 논문집
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• 제21권6호
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• pp.132-139
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• 2017

한랭지역의 동절기 교통안전을 위하여 제설제 살포가 다량으로 이루어지고 있는데, 그 살포량도 매년 증가하고 있는 실정이다. 일반적으로 사용되는 제설제는 염화칼슘($CaCl_2$), 염화나트륨(NaCl)과 같은 염화물계가 주성분으로, 국내에서는 대부분 염화칼슘을 주로 사용하고 있고, 미국이나 일본의 경우는 소금인 염화나트륨으로 모두 염소이온을 포함하고 있다. 염화칼슘 제설제가 포함하고 있는 염화물 때문에 제설제 살포시 염화물은 도로 구조물로 침투하여 염해에 의한 철근부식을 유발하여 실제 포장이나 손상된 교량 구조물 내에서의 구조적 성능저하를 야기하고, 동절기 동해와 함께 복합적으로 작용하여 표면 스케일링을 발생시키며, 특히 살포제에 의한 수질 오염과 같은 심각한 부작용을 초래하고 있다. 또한 콘크리트 도로포장 표면이 염화칼슘 제설제 사용 후 나타나는 열화현상으로 인하여 기존의 염화칼슘 제설제의 경우 시각적으로 교통 외관상 문제를 가속화시키고 있다. 따라서, 본 연구에서는 산업부산물인 폐유기산과 칼슘계부산물을 반응시켜 친환경 액상 제설제를 제조하고 그 특성을 분석하여 도로시설물에 적용가능성을 검토하였다.

• 생물환경조절학회지
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• 제21권4호
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• pp.354-361
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• 2012

외국에서 도입한 블루베리의 내한성을 평가하고, 목재수분계측기가 월동 중 블루베리 가지의 동해피해를 간편하고 신속하게 진단하는데 활용할 수 있는지를 알아보기 위하여 수행되었다. 월동 중 블루베리의 가지의 고사율은 0~100%로 다양하게 나타나 품종별 내한성의 차이가 컸다. 블루베리 가지의 저온처리에 따른 TTC 검정에서 품종별 OD값은 $-40^{\circ}C$ < $-21^{\circ}C$ < $4^{\circ}C$ 순으로 처리온도가 낮을수록 낮게 나타났다. 블루베리 가지의 저온처리에 따른 가지절단면의 색의 검정은 가지고 사율에 의한 내한성과 다른 결과와 차이가 있었다. 목재수분계측기에 의해 측정된 살아있는 블루베리 가지의 월동 중 최저 수분함량은 약 15%였으며, 월동 중 블루베리 가지의 위치별 수분함량은 나무 아랫부분일수록 높고 가지 끝으로 갈수록 낮았으나, 봄으로 접어들면서 가지 끝의 수분함량이 점점 높아져 20~40% 범위로 측정되었다. 월동 중 동해피해를 받은 가지는 점점 건조되어 수분함량이 5% 이하로 낮아졌다. 동해를 받은 블루베리 가지의 수분함량은 14% 수준 이하일 것으로 추정되며, 목재수분계측기가 블루베리 가지의 동해피해를 현장에서 신속하게 진단하는데 활용될 수 있을 것으로 기대된다.

• 대한한방내과학회지
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• 제30권3호
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• pp.612-623
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• 2009

Objectives : The water extract of Sopung-tang (SPT) has been traditionally used in the treatment of acute stroke in Oriental Medicine. Pro-inflammatory cytokines play a critical role in the onset of post-ischemic inflammatory cascades. The present study was designed to investigate the effects of SPT on pro-inflammatory cytokine production in a photothrombotic ischemia mouse model. Methods : After SPT oral administration to the mice for five days, with using Rose Bengal and cold light, photothrombotic ischemia lesion was induced in stereotactically held male BALB/c mice. Also, results including, gross finding lesion size, histopathological finding changes, and inflammatory cytokine expression changes from the photothrombotic ischemia mouse model were observed. Results : The photothrombotic ischemia lesion was decreased by the oral injection of SPT. Also, SPT inhibited the expression of TNF-$\alpha$, IL-$1{\beta}$, IL-6, the active form of caspase-3 protease, and transglutaminase-2 in the photothrombotic ischemia lesion. Conclusions : These results suggest that SPT protects the ischemic death of brain cells through suppression of the production of anti-inflammatory cytokines and catalytic activation of caspase-3 protease in the photothrombotic ischemia mouse model.

• Journal of Biosystems Engineering
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• 제19권4호
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• pp.358-368
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• 1994

Major factors in reducing the stacking strength of corrugated fiberboard boxes in cold storage or transport conditions are high relative humidity, causing elevated moisture absorption by the boxes. The bottom boxes in a stack will deform to the critical deflection causing agricultural products damage there, and eventually additional deflection will cause box collapse and finally toppling of the stack. The study was conducted to determine the water absorption characteristics and the compressive strength of the corrugated fiberboard boxes being widely used in packaging agricultural products in Korea. The sample boxes for the study were selected from the regular slotted containers (RSC) types, and one was the box used in apple packaging (Box A), another one was the box used in pear packaging (Box B). The corrugated shipping containers were made from a large portion of recycled fibers in Korea, and comparing with Box B, Box A was fabricated from fiberboard which contained more percentage of old corrugated containers (OCC) imported from foreign countries than domestic waste paper. The results obtained from the study were summarized as follows ; 1. Equilibrium moisture content (EMC) of the sample boxes was established after about 20 hours, and the EMC by absorption was lower than that by desorption. The EMC increased with the increasing of relative humidity and with the decreasing of temperature, and the rate of increasing was much higher above the relative humidity of 50%. 2. The maximum compressive strength of Box A was about 100 kgf greater than that of Box B on the same enviromental conditions. The strength of the sample boxes decreased rapidly with the increasing of relative humidity. The effect of relative humidity on the strength was a little higher than that of temperature. 3. As the applied load was progressively increased and a level was reached, the vertical side panels ($L{\times}D$) deflected laterally inwards or outwards. The panels deflected laterally inwards at higher relative humidity. 4. The maximum compressive deflection ratio and the critical deflection ratio of the sample boxes were increased linearly with the increasing of relative hunidity, but trends for its ratios showed inconsistant response to temperature.

• 한국유기농업학회지
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• 제22권2호
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• pp.255-268
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• 2014

We are now currently facing serious climate changes such as super typhoon, flood, intense heat, severe cold, super hurricane, drought, desertification, destruction of ecosystem, marine pollution, reduction of food production, destruction of tropical forests, exhaustion of water resources, climate refugees, etc. All of the above mainly derive from greenhouse gas exhaustion. Such harmful consequence might directly affect mankind's sustainable development. If we keep using resources that emits greenhouse gases, the global temperature will rise about $3.2^{\circ}C$ by year 2050. In case of $3^{\circ}C$ rise in temperature, it will result in abnormal climate which will bring about severe property damage. Moreover, 20~50% of the ecosystem will become extinct. As Korea's economy increasingly expands, so do our energy consumption rises. And because of the consequences that can be driven by increasing rate of resource use, not just Korea itself, but also the whole world should seriously concern about greenhouse gases. Although agricultural division only takes up about 3.2% of total greenhouse gas emission, the ministry of Agriculture, Food and Rural Affairs are taking voluntary actions to gradually reduce $CO_2$ and so does each and every related organizations. In order to reduce $CO_2$, introduction of new and renewable energy in farm house warming is crucial. In other words, implementing wood-pellet boiler and geothermal heat boiler can largly reduce $CO_2$ emission compared to diesel boiler. More importantly, not only wood-pellet and geothermal heat is pollution-free but they also have economic advantages some-what. In this thesis, the economic advantage and sustainablity will be introduced and proved through comparing practical analysis of surveyed farm house under structure employing wood-pellet boiler and geothermal heat boiler with Agriculture-Economic Statistic of 2012 who uses diesel boiler.

• 농촌계획
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• 제18권3호
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• pp.103-110
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• 2012

This study aims to find out the geographical distribution, the physical structure and characteristic of Gudle-jang Paddy-field in Cheongsando. On the basis of this study, the potential value and the assignment for the preservation of Gudle-jang Paddy-field were suggested. Gudle-jang Paddy-field is centrally distributed to Cheongsando and has various features as follows. First, it has the Ondol structure which is used Gudle-jang. Second, it has an irrigation canal which has functions of the tank and the prevention of cold-weather damage as well as the irrigation and drainage canal. The values of Gudle-jang Paddy-field are as follows; 1) It is the peculiar and inherent agricultural structure which is only found in Cheongsando. 2) It is the structure that the agricultural civil engineering and the agricultural water management technique of traditional methode are applied. 3) It has the worths of the traditional culture of Korea. 4) It is the important resource creating superb rural landscape of the region. In spite of these values of Gudle-jang Paddy-field, there were little efforts to preserve it. From now on, it is needed to form of sympathy about the value of Gudle-jang Paddy-field and to make efforts for preservation of it. Also the institutional and political strategy should be provided to preserve and manage Gudle-jang Paddy-field.