In this study, it evaluate the Impact fracture properties of fiber reinforced concrete and fiber reinforced cement composite. The types of fiber are Hooked-ended steel fiber and it was mixed 0.5, 1.0 vol.% in concrete and 1.0, 2.0 vol.% in cement composites. The Impact resistance performance was evaluated by measuring the fracture grade, penetration depth and scabbing depth

In this study, it evaluate the Impact fracture properties of fiber reinforced concrete and fiber reinforced cement composite. The types of fiber are Hooked-ended steel fiber and it was mixed 0.5, 1.0 vol.% in concrete and 1.0, 2.0 vol.% in cement composites. The Impact resistance performance was evaluated by measuring the fracture grade, penetration depth and scabbing depth

본 연구에서는 반구형과 평탄형의 비상체를 이용하여 일반콘크리트와 섬유보강콘크리트에 충격시험을 진행한 후 파괴깊이와 형 태, 파괴직경, 배면의 인장변형을 평가하였다. 선단면적이 작을수록 충격력의 집중에 의해 파괴깊이는 크고 표면파괴 직경은 작게 되는 것으로 확인되었다. 반면에 선단면적이 클수록 파괴깊이는 작지만 표면파괴직경은 크게 되었다. 일반콘크리트와 섬유보강 콘크리트에서 유사한 표 면파괴와 배면변형이 발생하였으나 인장변형의 크기는 일반콘크리트에 비해 섬유보강 콘크리트가 작은 것으로 나타났다. 또한, 비상체의 선 단형상에 따른 표면관입의 형태와 배면의 인장변형 사이에 직접적인 연관이 있는 것으로 사료된다. 따라서 콘크리트의 배면박리한계두께 예 측 시에는 표면관입깊이뿐만 아니라 배면의 변형거동 또한 고려할 필요성이 있을 것으로 사료된다.

Background : Recently, some of the previous stuies reported that was useful technique on growth and yield of organically grown ginseng transplantation in a rain shelter greenhouse. This study was conducted to investigate the optimum method of greenhouse shading for ginseng(Panax ginseng C. A. Meyer) cultivaton in the northern area of Ganwon, Korea. Methods and Results : We carried out to select optimal shade materials and light-penetrated ratio among polyethylene film with two-layered polyethylene net(PEF+PEN) and blue-white duplicated PE film(BWD-PEF) in the condition of greenhouse for ginseng cultivation. The order of light-penentrated ratio by shade meterials was PEN(75%)+PEF 〉 PEN(85%)+PEF 〉BWD-PEF(85%) 〉BWD-PEF(90%) and the order of air temperature was BWD-PEF(85%) 〉BWD-PEF(90%) 〉PEN+PEF(85%) 〉PEN+PEF(75%). The net photosynthetic rate was higher in PEN(75%)+PEF than other shading material treatments during growth season including summer high-temperature period. The root weight and yield were increased by 31.2~55.0% and 25.6~52.2%, respectively under PEN+PEF(75%) compared to other shading materials. Conclusion : We concluded that the PEN+PEF(75%) could be a good shading meterails of the greenhouse for organic 4-year-old ginseng cultivation in northern area of Gangwon, Korea.

It is difficult to predict scabbing limit thickness of fiber reinforced concrete, because existing formulas are not consider fiber reinforcing effect. So, In this study, obtaining the fiber reinforced factor and factors are applied to Modified NDRC formula. As results, it was possible to make accurate prediction for scabbing limit thickness of fiber reinforced concrete.

The purpose of this study was to evaluate the dynamic mechanical properties of fiber reinforced cement composite according to the strain rate. Experiment result, the compressive strength was improved by increase the strain rate. But strain at the peak stress and elastic modulus was not affected by the strain rate.

이 글은 ‘역사적 평화교회’로 불리는 메노나이트교회의 평화주의 전통에 대한 연구로서, 다음과 같은 몇 가지 사실에 주목하였다. 첫째, 16세기 종 교개혁과 재세례파의 형성과정을 논구하고 이런 과정에서 메노나이트 교 회의 생성과 그 신학에 주목하였다. 둘째, 메노나이트교회의 평화주의 전 통을 파악하기 위해 메노나이트교회의 시원이 되는 메노 사이먼스(Menno Simons, 1496-1561)의 생애와 저술을 통해 그의 평화주의 사상의 연원을 추적하였고, 그것이 성경과 초기 기독교의 가르침에 근거하였음을 제시하 였다. 특히 메노 사이먼스는 ‘그리스도를 본받음’(imitatio Christi)를 ‘비폭 력 평화’에 찾았음을 지적하였다. 셋째, 이런 평화주의가 재세례파의 첫 신 앙고백서인 슐라이트하임 신앙고백서에서 표명되었다는 점을 지적하고, 이 신앙고백서의 가르침이 그 이후 어떻게 계승되어 왔던가를 지적하였다. 넷째, 이런 전통을 계승하는 메노나이트 교회의 양심에 근거한 병역거부 에 대해 기술하였다. 양심적 병역거부는 비폭력 평화주의의 단순한 적용이 라는 점을 지적하고, 양심에 의한 병역거부는 초기 기독교에서부터 있어왔 다는 점을 지적하고, 그 이후 정당정쟁론의 대두, 16세기 아나뱁티스트들 을 통한 탈 콘스탄틴주의와 병역거부에 대해 기술하였다. 또 16세기 이후 메노나이트교회에 의한 평화주의 전통이 어떻게 계승되어 왔는가를 지적함으로 메노나이트교회의 평화주의 전통을 제시하고자 시도하였다. 특히 메노나이트교회가 ‘제자도’로 고양해 왔던 비폭력(non-violence), 반전운동 (anti war movement), 양심에 따른 병역거부(conscientious objection to Military Service), 화해(reconciliation), 앙갚지 않음(un-retaliation) 등과 같 은 고상한 가치들은 남북한의 군사적 대결과 위협 하에 있는 오늘의 한국 에 교훈과 자극을 주고 있음을 지적하고, 메노나이트교회의 평화주의는 근 본적으로 ‘그리스도를 본받는’ 삶의 방식이라는 점을 지적하였다.

This study was conducted to investigate effects of waterlogging on the growth, physiological responses, and yield of Kimchi cabbage. The growth of Kimchi cabbage with applied optimized air temperature (set to 20℃) was greater than those with high air temperature (set to 30℃) and the growth significantly decreased by severe waterlogging treatment. The net photosynthetic rate of outer leaves on one hour after waterlogging treatment was higher at 72 hours waterlogging treatment in 20℃ and lower at 24 hours of waterlogging treatment in 30℃. The root activity was decreased by the elevation of waterlogging periods in 20℃ treatment and lower by the short of waterlogging periods in 30℃ treatment. The ratio of formality with non-waterlogging treatment was approximately 64% under 20℃ air temperature and that of range was from 16 to 30% under 30℃. The yield under 20℃ showed higher than that under high air temperature. The non-waterlogging treatment in 20℃ had 4,463 kg/10a, which was the greatest among all treatments, while yields of non-waterlogging treatment at 30℃ were significantly low as 1,082 kg/10a. Results suggested that additional drainage work should be needed to overcome waterlogged conditions of open field during heavy rainfall and should be drainage as soon as possible if there are waterlogging.

Shock wave caused by the high-velocity impact causing the tensile strain and stress on the rear side. When the tensile strain and stress exceeds the tensile strength of the concrete, scabbing and perforation were occurred. The strain on the rear side was reduced due to improvement of the tensile strength by fiber reinforcement.

Thin plate amorphous steel fiber has more tensile strength and corrosion resistance than general steel fiber, and it has different fiber direction by casting direction. In this study, evaluating impact resistance and sectional crack characteristic of amorphous steel fiber-reinforced cement composites by casting direction.

In this study, rear strain behavior of concrete panel considering the projectile nose shape was evaluated. It was considered that penetration and scabbing properties are different by each projectile nose shape. so it should be taken into account the rear strain behavior by projectile nose shape, when predicting scabbing, perforation of concrete by projectile impact.

When the concrete is subjected to impact of the projectile, compressive stress wave is transmitted to the rear side. When the compressive stress wave reached the rear side, is was reflected as a tensile wave. And, when the tensile stress in the concrete matrix exceeded the dynamic tensile strength, crack in the concrete was occurred.

In this study, rear failure properties of fiber reinforced concrete considering projectile type was evaluated. It was considered that scabbing of Flat nose projectile reduced more than sperical nose projectile by dispersion of impact force.

The maize production in South-eastern Asian countries showed a continuous increase with increasing poultrylivestock from the beginning of the 1990s to early 2010. Also the need for a new variety development of each contries was increased rapidly in the same period. Single-Cross hybrid varieties have been developed and supplied from 2001 instead of multi-cross maize varieties since 1992 in Indonesia. In Cambodia, CP group is mainly manufacturing feeds with most of the forage maize from farmers who are growing its seeds from the company. Cambodian main cultivars are varieties of multinational corporations such as DK8868 from Monsanto, NK6326, NK7328 from Syngenta and CP333 from CP group including local business company. Vietnam is the main maze importing country in South-Eastern Asia which had imported 13 times scale of amount compared to exports in average from 1990 to 2011. Vietnamese government has developed a range of varieties for improving their efficiency in production, such as the LVN-10 with political investments. Their production has been reached to 80% of the total. According to the 2012 MIFAFF (Ministry for Food, Agriculture, Forestry and Fisheries) data in Korea, domestic edible maize cultivation area was approximately 15,000ha. It showed 74,399 tons of production, 3.8% of food self-sufficiency in maize and around 0.9% of grain self-sufficiency rate. The consumption of grain is mostly rely on imports in Korea. To overcome the limit of the domestic seed market and increase maize self-sufficiency, the need to develop maze varieties for world-class is increasing at present through analyzing the market trend and prospect of the seed industry in South-eastern Asia

This study was conducted to determine the effects of high temperature and deficit irrigation on growth and yield of hot pepper. Hot pepper was subjected to four irrigation treatments: fully irrigation (FI), 10, 20, and 30 days deficit irrigation (DI) combination with high temperature treatment. Control plants were grown natural environment and conventional culture methods. The plant height treated with high temperature was significantly higher than that of control plant. At FI combination with high temperature treatment, growth parameters such as stem diameter, leaf area, fresh and dry weight were the greatest. The yield was the greatest (2,036 kg/10a) under control, DI combination with high temperature treatment decreased by approximately 42% compare with FI combination with high temperature treatment. The number of abnormal fruits was approximately 38/plant under control, which was the smallest and that of 30 days DI combination with high temperature was higher 3.3 times compare with control. Flower abscission and calcium deficiency induced by DI treatments, especially those physiological disorder promoted by increasing DI treatments period. Results indicated that yield of hot pepper reduced by DI treatments, these results suggest that the growers should irrigate to proper soil moisture for preventing reduction of total fruit yield.

In this study, using the general-purpose structural analysis program, prediction of thermal crack of ultra-high-strength concrete(UHSC) columns were investigated. Parameters were column shape and column size of UHSC columns that have higher temperature rise than normal strength concrete. Thermal crack behaviors according to UHSC column shape were investigated.

수박(Citrullus lanatus)은 대표적인 고온성 채소이지만 대부분이 저온기에 정식하여 재배 하기 때문에 유묘기 저온 으로 인하여 생육 불량하여 고품질 안정생산에 많은 장해 요인이 되고 있어 유묘기 내저온성 품종개발 필요성이 커지고 있다. 따라서 본 연구에서는 수박유전자원 16개 계통을 NDVI영상분석을 통하여 선발된 저온 신장성 우수 계통(PI299379, PI482261)과 시판품종삼복꿀, 수퍼금천을 식물생장상 28℃/18℃에서 20일간 육묘하여 3일간 15℃ 에서 순화 시킨 후 10℃에서 2일간 저온 처리(순화구)와 순화 없이 10℃로 2일간 저온처리(급저온구) 하였고 대조 구는 주야간 온도를 28℃/18℃로 하여 유전자 발현의 차이를 분석하였다. 그 결과 대조구와 저온처리구의 발현양 상 차이를 보이는 17개의 단편의 염기서열 분석을 통하여 확인하였다. 단편 서열을 바탕으로 한 RT-PCR 분석을 통하여 저온신장성 우수계통에서만 특이적으로 발현하는 calcium-binding EF hand family protein, trypsin inhibitor, Sigma factor binding protein, 등 4개의 유전자를 확인하였다

Growth and physiological disorders caused by abnormally low temperatures were evaluated in pepper, an important field crop in Korea. In addition, the effects of chemical treatment using glutamine was verified on minimizing the damages by low temperature. The growth of pepper plants in stem length and diameter was suppressed as the temperature decreased from 25℃, and the suppression level was the highest for plants grown for 90 days at 20℃. However, root growth was not affected by the different temperatures. The number of leaf and leaf area decreased at the temperatures below 25C, an optimum temperature for growth. Fresh weight and dry weight decreased for plants grown at 20℃. Pepper fruit yield also decreased by 11% at 20℃ in comparison to 25℃. Falling blossom rate was different depending on the growth temperature, and the rate was 27.2% at 25℃, 35.2% at 22.5℃, and 41.0% at 20℃, indicating that falling blossom rate increased as temperature decreased. Different growth temperatures did not affected on the level of symptom of calcium deficiency and Phytopathora blight. Falling blossom was severe at abnormally low temperature of 20℃, but the treatment of glutamine reduced falling blossom rate and increased the yield by 7.0% as compared to control. The optimum concentration of glutamine treatment was 10 mg/L for yields.

The purpose of this article is analyzing the economic impacts of abnormal climate on fall chinese cabbage farmers and consumers in Korea, with employing the equilibrium displacement model. Our results show that there were little difference in gross farm income, even though there were significant yield reductions due to abnormal climate changes. However periodic occurrences of abnormal climates caused serious damage to consumption levels which had declined by 10.6~17.1 percent with higher prices by 15.3~24.6 percent than normal climate years since 1990.

여주는 몇몇 열대지역에서 중요한 채소 작물이다. 여주 과 실이 의학적으로 효능이 있는 활성물질을 포함하고 있음에도 불구하고, 한국에서는 주로 장식용으로 이용되어 왔다. 최근 여주의 미숙과실에 있는 항당뇨성분 때문에 여주에 대한 관 심이 증가하고 있다. 그러나 재배법과 기능성성분에 대한 연 구가 거의 수행되지 않았다. 본 연구에서는 항 당뇨성분인 카란틴 성분 함량이 높은 유전자원을 선발하기 위하여 카란틴 성분을 분석하였다. 여주 과실의 카란틴 성분 분석은 31자원 의 인공교배된 착과 후 15일 경과한 과실을 이용하였다. 카란틴 함량은 15.1∼161.4 μg·g -1이었으며, 건물중은 221 ∼2,097 g이었다. ‘K169998’, ‘K042800’, ‘K170002’, ‘Hwanock’ 그리고 ‘Nockwoo’ 5개 계통의 카란틴 함량은 각각 143.7, 104.6, 103.5, 161.4, 101.1 μg·g -1이었다. 이러한 결과는 항 당뇨 성분인 카란틴 함량이 높은 여주자원 선발에 활용될 수 있으며, 안정적인 고품질 여주 자원 선발에 기초자료로 이용 될 것이다. 향후 여주의 수확시기가 어떻게 카란틴 함량 변화 에 관여하는지에 대한 기작 규명 연구가 필요하다.