• Title/Summary/Keyword: 유기논

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Effects of Diffusibility of Bubbling Tablet Herbicide Formulations for Paddy Rice (수도용 발포성정제 제초제의 확산성에 미치는 영향)

  • Kim, Man-Ho;Ryang, Kwang-Rok;Lee, Chang-Hyeuk;Shim, Jae-Weon;Kim, Kyung-Hyun;Yoon, Cheol-Su;You, Yong-Man;Pyon, Jong-Yeong
    • The Korean Journal of Pesticide Science
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    • v.9 no.4
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    • pp.401-410
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    • 2005
  • A series of studies involving formulation processes, bubbling activity test, diffusibility test and biological efficacy test was undertaken to develop Jumbo herbicide formulations in paddy rice field. Gas evolution speed from the tablets prepared by different organic acids was in the order of oxalic acid, malonic acid, citric acid, and tartaric acid. The total volume of evolved gas from the tablet and diffusibility of the active ingredient in the submerged water were increased with increase of water temperature; the volume from 1 g of tablet at 10, 15, 25 and $30^{\circ}C$ for 5 minutes after immersion into water was 20, 25, 28, 45, 57 mL, respectively. The concentration of halosulfuron-methyl and pyriminobac-methyl in submerged water at 5, 15, 20 and $30^{\circ}C$ at the 2.4 m distance from the applied spot of the tablet was 20, 48, 85, and 97% of the concentration of treated spot, respectively. The evolved gas volume from the tablets was not affected by pH of submerged water. The concentration of halosulfuron-methyl in different sizes of submerged water within 24 hours after treatment of the tablet was maintained 0.16 ppm, which is ideal concentration at standard dosage regardless of the submerged water area. The concentration of pyriminobac-methyl was also uniformly dispersed in the water within 24 hours after applying it into the submerged water. The wind velocity of 5 m $sec^{-1}$ on concentration distribution of halosulfuron-methyl and pyriminobac-methyl in the submerged water 24 hours after treatment was not influenced; an equal concentration in the up the wind and down the wind from the applied spot was maintained. Spot treatments of one tablet formulations(5 g) including 4 times higher dosage at 4 different spots resulted in even concentration distribution of active ingredient in the water 24 hours after applying it into the submerged water.

Application Effect of Food Waste Compost Abundant in NaCl on the Growth and Cationic Balance of Rice Plant in Paddy Soil (NaCl을 다량 함유한 음식물쓰레기 퇴비 시용이 논 토양에서 벼의 생육과 체내 양이온 균형에 미치는 영향)

  • Lee, Sang-Eun;Ahn, Hyun-Jin;Youn, Seung-Kil;Kim, Seak-Min;Jung, Kwang-Young
    • Korean Journal of Soil Science and Fertilizer
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    • v.33 no.2
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    • pp.100-108
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    • 2000
  • High sodium contents in food-waste compost(FWC) is the greatest limitation to recycle it to arable lands in Korea. The effects of the FWC application to paddy soil on the growth of rice plants, cationic balance in plants, and the sodicity of soil have been studied in pot trials. The effects of FWC application were compared with those of NaCl compound and swine manure compost(SMC) application. $Na_2O$ contents of FWC were high as 2.2%. Immediately after transplanting, rice plants in three treatments showed severe wilting in the order of 40Mg FWC $ha^{-1}$ > NPK+900kg $NaClha^{-1}$ > 20Mg FWC $ha^{-1}$. The high EC value and volatile acid contents of soil solution were regarded as the cause of severe wilting of young rice plants. Increase of NaCl application rate upto $900kgha^{-1}$ showed no significant reduction of dry matter yield at harvesting stage. Regardless of application rates FWC reduced the dry matter yield at harvesting stage, while SMC increased it with increase of application rates upto $40Mgha^{-1}$. In NPK+NaCl and FWC treatments, Na contents and equivalent ratio in plants increased linearly with increase of Na application rates. Between Na and K equivalent ratio negative correlation with high significance was shown. In contrast to much difference of Na, K, and Na/K equivalent ratio among treatments, little difference of Na+K indicated the physiological substitution of Na for K in rice plants. Na use efficiency in NPK+NaCl and FWC treatments showed 12-22%.

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담자균류 ${\beta}$ -글루칸의 특성 및 생산

  • Hong, Eok-Gi
    • Proceedings of the Korean Society of Life Science Conference
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    • 2002.05a
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    • pp.17-22
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    • 2002
  • 지구상에는 수천종의 버섯류가 자생하고 있어 유전자원으로서의 중요성이 지대할 뿐만 아니라 기능성 식품소재 및 각종 약리 활성을 나타내는 신약개발 소재로도 크게 주목을 받고 있다. 이들 버섯은 균사체의 영양대사로 얻어지는 대사산물이 축적된 자실체의 형태로 나타나는데, 최근에 와서 자실체 및 균사체의 추출물이나 균사체 배양물이 체질개선이나 각종 병의 예방과 치료에 효과가 있는 것으로 밝혀져 건강식품이나 의약품으로서의 용도가 크게 증가하고 있는 실정이다. 특히, 담자균이 생산하는 특정 구조를 갖는 다당류는 오래전부터 종래의 화학요법제와는 달리 숙주내의 면역 기능을 부활하여 소위 면역요법제로서의 항암효과를 나타냄이 알려져왔었다. 현재까지 제약 및 의학적인 방법이 질병의 주된 치료방법으로 이용되어 왔지만 최근에 특정식품의 섭취가 만성질환의 발생을 억제 또는 지연시킨다는 연구 보고가 나오면서부터 만성질환의 치료방법으로서 식이요법을 중요하게 생각하게 되었다. 따라서 새로운 식품소재 및 가공식품의 개발을 통한 성인병 등의 각종 질병예방이 국민보건문제 해결에 필수적이다. 현재 일본 등에서는 표고버섯, 구름버섯 및 치마버섯 유래의 다당체 또는 단백다당체인 lentinan, krestin 또는 PS-K, schizophyllan 및 PSP 등이 실용화되어 높은 가격에 판매되고 있다. 국내에서도 야생 구름버섯 자실체로부터 추출한 단백 다당체인 Copolang(광동제약)이 개발되어 PS-K와 유사하게 암의 치료에 병행 사용되고 있고, 또 강력한 항암활성이 보고된 상황버섯의 균사체 추출물인 단백 다당체가 Mesima-Ex FK(한국신약)라는 상품명으로 암의 치료에 병행 사용되고 있는 것으로 알려지고 있다. 담자균류와 아울러 미생물 유래 다당체는 그 구조와 특성에 있어서 매우 다양함을 지니고 있다. 이러한 미생물 유래 다당류의 공업적 생산과 이용에 대한 연구로서는 Leuconostoc mesenteroides가 생산하는 dextran이 혈장증량제로 개발된 이래 Xanthomonas campestris가 생산하는 pullulan, Zoogloea rgmigera가 생산하는zooglan둥이 대표적인 예로 보고되고 있다. 한편, 미생물 유래 다당류는 구성당, 분자량, 화학적 구조 등과 같은 특성의 차이에 의해 많은 종류가 존재하고 있으며, 다양한 물성 및 유화제, 응고제, gel 형성제, 필름 형성제, 흡착제, 안정제, 접착제 등과 같은 용도로 광범위하게 이용되고 있다. 또한 근래에 들어서는 미생물 유래 다당체가 지니는 항암활성이 확인되어 새로운 의약품으로서의 개발 가능성이 기대된다. 그 밖에도 기존에 알려져 있는 식물 및 해조류 유래의 다당체와는 달리, 발효조를 이용한 연속배양에 의해 공업적 대량 생산이 가능하며, 더욱이 생산된 다당체의 분리 및 회수가 용이하다는 이점을 지니고 있다. 최근에 들어서는 유전공학적 기법을이용한 고생산성 변이균주 및 새로운 기능을 지닌 다당체의 개발에 관한 연구가 보고되고 있는 등 고부가가치를 지닌 새로운 바이오 소재로서의 기능 및 용도 개발에 관한 연구가 활발히 진행되고 있다. 이러한 항암 활성을 나타내는 여러 가지 담자균류중 Agaricus blazei로부터 생산되는 다당체는 고형암 이외에 S형 결장암, 난소암, 유방암, 폐암, 간암 등에 효과가 입증되었고, 천연물질에 의한 암 면역요법으로 각광을 받고 있으며, 항암 및 항virus의 완치율과 저지율에서 현재 여러가지 약효가 있는 버섯중에서도 탁원한 효과가 있는 것으로 증명되고 있다. 이들 다당체는 사이토카인을 생산시켜서 T임파구와 B임파구의 항원 특이적인 면역반응을 활성화시키고, 세포장해성 T세포와 활성화 대식세포의 세포장해 기능을 충진시켜서 암세포를 파괴시킨다. 또한 콜로니 자극인자인 사이토카인을 생산시켜서 면역담당세포의 신생을 촉진시키기도 하며, 암의 화학요법과 방사선 요법으로 저하된 백혈구를 회복시키는 역할을 한다. 따라서 최근의 연구동향은 생산된 다당체의 항암활성을 향상시키고자 하여 배양기간중에 interleukin을 의도적으로 첨가하는 경향이 있다. 이러한 항암 활성을 나타내는 담자균체 유래 다당체는 버섯의 기원에 따라 그 형태에 약간의 차이를 나타내기는 하나 그 기본 형태는 ${\beta}-(1,6)-glucosyl$ 분지를 가진 ${\beta}-(1,3)-glucan$이며, 평균 분자량은 50 ${\sim}$ 200만 정도이다. Agaricus blazei의 원산지인 브라질의 피에다데(Piedade) 지방의 환경조건(산지의 습도는 80%, 낮 기온 $35^{\circ)C$, 밤 기온 $20{\sim}25^{\circ}C$로 대단히 높으며, 정기적으로 열대지방 특유의 소나기가 내리는 지역)에서 볼 수 있듯이 Agaricus blazei의 성장 환경은 매우 까다로운 편이며, 날것으로는 보관이 잘 안되기 때문에 그 재배에 큰 어려움이 있다. 또한, 고체배양에 의해 생산된 버섯 자실체로부터 유기용매 및 열수추출 방법으로 다당체를 생산하는 방법은 균일한 형태의 버섯 자실체를 공급받기가 어렵기 때문에 다당체의 생산 수율이 낮고, 많은 노동력이 요구되는 어려움이 있다. 그러나 액체배양에 의한 다당체 생산의 경우는 고체배양에 의한 다당체 생산에 비해 일정한 조건하에서 배양이 가능하다는 장점이 있으며, 항상 균일한 균사체 및 배양액을 얻을 수 있다. 따라서 원하는 유용물질을 쉽게 획득할 수 있는 장점이 있다.

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Effects of streambed geomorphology on nitrous oxide flux are influenced by carbon availability (하상 미지형에 따른 N2O 발생량 변화 효과에 대한 탄소 가용성의 영향)

  • Ko, Jongmin;Kim, Youngsun;Ji, Un;Kang, Hojeong
    • Journal of Korea Water Resources Association
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    • v.52 no.11
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    • pp.917-929
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    • 2019
  • Denitrification in streams is of great importance because it is essential for amelioration of water quality and accurate estimation of $N_2O$ budgets. Denitrification is a major biological source or sink of $N_2O$, an important greenhouse gas, which is a multi-step respiratory process that converts nitrate ($NO_3{^-}$) to gaseous forms of nitrogen ($N_2$ or $N_2O$). In aquatic ecosystems, the complex interactions of water flooding condition, substrate supply, hydrodynamic and biogeochemical properties modulate the extent of multi-step reactions required for $N_2O$ flux. Although water flow in streambed and residence time affect reaction output, effects of a complex interaction of hydrodynamic, geomorphology and biogeochemical controls on the magnitude of denitrification in streams are still illusive. In this work, we built a two-dimensional water flow channel and measured $N_2O$ flux from channel sediment with different bed geomorphology by using static closed chambers. Two independent experiments were conducted with identical flume and geomorphology but sediment with differences in dissolved organic carbon (DOC). The experiment flume was a circulation channel through which the effluent flows back, and the size of it was $37m{\times}1.2m{\times}1m$. Five days before the experiment began, urea fertilizer (46% N) was added to sediment with the rate of $0.5kg\;N/m^2$. A sand dune (1 m length and 0.15 m height) was made at the middle of channel to simulate variations in microtopography. In high- DOC experiment, $N_2O$ flux increases in the direction of flow, while the highest flux ($14.6{\pm}8.40{\mu}g\;N_2O-N/m^2\;hr$) was measured in the slope on the back side of the sand dune. followed by decreases afterward. In contrast, low DOC sediment did not show the geomorphological variations. We found that even though topographic variation influenced $N_2O$ flux and chemical properties, this effect is highly constrained by carbon availability.

A Study on the Environmental Characteristics of Water Quality and Sediments in Suncheon Bay (순천만 수저질 환경특성에 관한 연구)

  • Park, Sangsook;Heo, Sung-sil;Choi, Jeong-min;Woo, Sung-won
    • Proceedings of the Plant Resources Society of Korea Conference
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    • 2019.10a
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    • pp.9-10
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    • 2019
  • 순천만은 순천시의 남쪽에 위치하여 여수반도와 고흥반도의 사이에 있는 만 지형 형태로 만 전체를 순천만이라고도 하나, 보통 고흥군반도와 여수반도 사이의 만을 여자만이라 하고 만내부에 위치한 여자도라는 섬의 위쪽으로 순천시의 해안하구에 형성된 지역을 순천만이라 일컫는다. 순천만은 순천시에서 유입되는 동천과 이사천 및 해룡천의 하류에 형성되어 있어서 육지부에서 유입되는 퇴적물과 유기물로 인하여 갯벌과 갈대등이 잘 형성된 습지로서 2003년 12월 31일 해양수산부 갯벌 습지보존지역으로 지정되어 관리되고 있으며, 2004년에는 동북아 두루미 보호 국제네트워크에 가입하였고, 2006년 1월 국내 연안습지로는 최초로 람사르협약에 "Suncheon Bay"로 등록되었으며, 2016년 6월에는 람사르습지로 지정된 국내외적으로 중요한 습지이다. 순천만습지에 형성되어 있는 갯벌($28.0km^2$)은 세계 5대 연안습지 중 하나로서, 넓은 사니질 갯벌과 갈대군락이 잘 발달되어 있는 생태계의 보고(寶庫)이자 소중한 생태자원으로서, 순천시에서는 순천만을 자연생태공원으로 지정하여 보호 관리하고 있으며, 각종 자연학습자료들과 영상물들을 갖춘 생태전시관과 갈대숲 탐방로, 용산전망대, 야생화 정원, 담수습지, 갈대정자, 갯벌관찰대 등 사계절 생태체험을 위한 각종 시설들을 잘 갖춰놓고 많은 관광객의 이용할 수 있도록 하고 있다. 갯벌은 바닷가의 넓은 벌판이란 뜻으로서 삼면이 바다인 우리나라는 갯벌의 전체 면적이 약 $2,500km^2$에 달하는데 여기에는 많은 종류의 다양한 생물들이 살아가고 있으며 어민들의 생계에 지대한 영향을 주고있다. 이러한 갯벌은 퇴적된 입자의 구성에 따라 펄갯벌, 모래갯벌, 혼합갯벌 등으로 구별되는데 이에 따라 갯벌 생태계를 구성하고 있는 생물들의 종류도 바뀌게 된다. 순천만갯벌과 여기에 조성되어 있는 습지환경에 따라 확인되고 있는 수산자원으로는 새꼬막, 꼬막, 눈알고둥, 갯고둥, 비툴이고둥, 돌조개, 접시조개, 새알조개, 가무락조개, 바지락, 우럭, 가재붙이, 방게, 칠게, 농게 등의 저서 생물들과 짱뚱어, 문절망둑 등의 어류가 있으며, 해조류로 우뭇가사리 등이 있고, 인근의 어민들의 어업형태는 꼬막 등 패류의 채취나 종패를 뿌려 일정기간 양성하여 수확하는 양식업, 육상부에서 폐염전 등을 활용한 전어나 새우 등을 양식하는 양식업, 수산물을 직접 손이나 간단한 도구를 이용하여 잡는 맨손 어업 형태가 주를 이루고 있는 것으로 나타나고 있다. 이와 같이 국내외적으로 중요할 뿐만 아니라 인근의 어민들의 생계에도 지대한 영향을 미치고 있는 순천만의 습지는 뻘층이 깊고, 분해성 미생물이 다양하게 서식하여 유기물 분해능력이 뛰어나며, 유기영양분이 풍부하여 우리나라에서 가장 질이 좋은 습지로 평가되고 있으나, 순천시 등 순천만 인근에 거주하고 있는 인간의 활동에 따른 간섭에 많은 영향을 받고 있으며, 이에 따라 끊임없는 생태환경이 변화하고 있어서 순천만의 효율적인 보전 및 지속가능한 이용을 위해서는 생태계에서 가장 기본적인 요소인 수 저질 환경의 지속적이고 체계적인 조사 및 관리가 필요하다. 한편, 오염물질의 70% 이상은 하천이나 강을 통해서 해역으로 유입된다고 알려져 있기 때문에 생태계의 보고(寶庫)라고 알려진 순천만의 지속적인 보존 및 관리를 위해서는 유입수계 하천의 수질현황 및 오염물질의 주요 배출원을 파악하고, 이에 대한 저감대책을 수립할 필요가 있다. 따라서 본 연구는 순천만의 수저질 특성과 여기에 유입되는 하천의 수질환경 현황 및 오염원을 파악함으로써 순천만의 보전을 위한 효율적 관리방안을 제시하는 것을 목적으로 수행되었다. 연구의 결과에 따르면, 순천만의 수질평가지수에 의한 등급(WQI)은 III등급으로 나타나고 있으며, 득량만, 광양만 등에 비해 비교적 높은 유기물 및 T-N, T-P의 농도 분포를 보이고 있는 것으로 조사되었다. 이는 순천만에 유입되는 하수종말처리장의 방류수와 도시하수가 유입되어 그대로 방류되고 있는 해룡천 및 연안에 위치한 어촌으로부터 직접 방류되고 있는 일부 정화조 유출수 등, 다양한 원인에 의한 것으로 판단되며 이들의 관리가 부실할 경우 순천만의 갯벌과 습지의 지속가능한 생태환경유지는 쉽지 않다. 따라서 이를 효율적으로 관리하기 위해서는 순천만 연안의 오염물질 방류를 총량관리로 전환하여 철저히 관리하는 것이 필요할 것으로 판단된다.

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Assessment of Methane Production Rate Based on Factors of Contaminated Sediments (오염퇴적물의 주요 영향인자에 따른 메탄발생 생성률 평가)

  • Dong Hyun Kim;Hyung Jun Park;Young Jun Bang;Seung Oh Lee
    • Journal of Korean Society of Disaster and Security
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    • v.16 no.4
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    • pp.45-59
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    • 2023
  • The global focus on mitigating climate change has traditionally centered on carbon dioxide, but recent attention has shifted towards methane as a crucial factor in climate change adaptation. Natural settings, particularly aquatic environments such as wetlands, reservoirs, and lakes, play a significant role as sources of greenhouse gases. The accumulation of organic contaminants on the lake and reservoir beds can lead to the microbial decomposition of sedimentary material, generating greenhouse gases, notably methane, under anaerobic conditions. The escalation of methane emissions in freshwater is attributed to the growing impact of non-point sources, alterations in water bodies for diverse purposes, and the introduction of structures such as river crossings that disrupt natural flow patterns. Furthermore, the effects of climate change, including rising water temperatures and ensuing hydrological and water quality challenges, contribute to an acceleration in methane emissions into the atmosphere. Methane emissions occur through various pathways, with ebullition fluxes-where methane bubbles are formed and released from bed sediments-recognized as a major mechanism. This study employs Biochemical Methane Potential (BMP) tests to analyze and quantify the factors influencing methane gas emissions. Methane production rates are measured under diverse conditions, including temperature, substrate type (glucose), shear velocity, and sediment properties. Additionally, numerical simulations are conducted to analyze the relationship between fluid shear stress on the sand bed and methane ebullition rates. The findings reveal that biochemical factors significantly influence methane production, whereas shear velocity primarily affects methane ebullition. Sediment properties are identified as influential factors impacting both methane production and ebullition. Overall, this study establishes empirical relationships between bubble dynamics, the Weber number, and methane emissions, presenting a formula to estimate methane ebullition flux. Future research, incorporating specific conditions such as water depth, effective shear stress beneath the sediment's tensile strength, and organic matter, is expected to contribute to the development of biogeochemical and hydro-environmental impact assessment methods suitable for in-situ applications.

Estimation of Rice Cultivation Impacts on Water Environment with Environmental Characteristics and Agricultural Practices by Nitrogen Balances (질소수지에 의한 환경특성과 영농방법별 벼농사의 수질영향 평가)

  • Roh, Kee-An;Kim, Min-Kyeong;Ko, Byong-Gu;Kim, Gun-Yeob;Shim, Kyo-Moon;Lee, Deog-Bae
    • Korean Journal of Soil Science and Fertilizer
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    • v.42 no.6
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    • pp.439-446
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    • 2009
  • Nitrogen balance in the regional scale which was calculated the difference between nitrogen input and output was estimated to assess the impact of rice cultivation on water environment. Nitrogen balances in Gyeonggi province, where nitrogen concentration in irrigation water was high and in Chungnam province, where nitrogen absorbtion by rice was high, were -5.4 and -8.3 kg $-8.3kg\;ha^{-1}\;yr^{-1}$, respectively. Nitrogen balances of paddy field in Gangwon province, where nitrogen output was small and irrigation water was clean, and in Gyeongnam province, where organic matter content of soil was high and rice yield was low, were 4.9 and $14.0kg\;ha^{-1}\;yr^{-1}$, respectively. Average nitrogen balance and total nitrogen absorption of paddy field in Korea were estimated to $-0.3kg\;ha^{-1}\;yr^{-1}$ and $-3,315Mg\;yr^{-1}$, respectively. When the nitrogen concentration in irrigation water was increased by $1mg \;L^{-1}$, nitrogen balance of rice paddy changed by $-2.91kg\;ha^{-1}\;yr^{-1}$. Also, when nitrogen fertilizer applied was decreased from 110 to $90kg\;ha^{-1}$ and the same harvest was maintained, the nitrogen absorption by rice paddy from irrigation water was estimated to increase by 10,600 Mg per year in Korea. However, in cases, the harvest was reduced to either 90% or 85%, nitrogen balances were changed from -11.7 to -2.3 and $2.4kg\;ha^{-1}$, respectively. These results suggest that the reduction of nitrogen fertilizer use may not always lead to a negative nitrogen balance and sustainable agriculture can achieve by not cutting down the use of fertilizer only but by reduction of fertilizer application concurrently by maintenance of harvest and by utilization of environmental characteristics such as nutrient contents in irrigation water and soils.

A Study on Improvements on Legal Structure on Security of National Research and Development Projects (과학기술 및 학술 연구보고서 서비스 제공을 위한 국가연구개발사업 관련 법령 입법론 -저작권법상 공공저작물의 자유이용 제도와 연계를 중심으로-)

  • Kang, Sun Joon;Won, Yoo Hyung;Choi, San;Kim, Jun Huck;Kim, Seul Ki
    • Proceedings of the Korea Technology Innovation Society Conference
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    • 2015.05a
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    • pp.545-570
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    • 2015
  • Korea is among the ten countries with the largest R&D budget and the highest R&D investment-to-GDP ratio, yet the subject of security and protection of R&D results remains relatively unexplored in the country. Countries have implemented in their legal systems measures to properly protect cutting-edge industrial technologies that would adversely affect national security and economy if leaked to other countries. While Korea has a generally stable legal framework as provided in the Regulation on the National R&D Program Management (the "Regulation") and the Act on Industrial Technology Protection, many difficulties follow in practice when determining details on security management and obligations and setting standards in carrying out national R&D projects. This paper proposes to modify and improve security level classification standards in the Regulation. The Regulation provides a dual security level decision-making system for R&D projects: the security level can be determined either by researcher or by the central agency in charge of the project. Unification of such a dual system can avoid unnecessary confusions. To prevent a leakage, it is crucial that research projects be carried out in compliance with their assigned security levels and standards and results be effectively managed. The paper examines from a practitioner's perspective relevant legal provisions on leakage of confidential R&D projects, infringement, injunction, punishment, attempt and conspiracy, dual liability, duty of report to the National Intelligence Service (the "NIS") of security management process and other security issues arising from national R&D projects, and manual drafting in case of a breach. The paper recommends to train security and technological experts such as industrial security experts to properly amend laws on security level classification standards and relevant technological contents. A quarterly policy development committee must also be set up by the NIS in cooperation with relevant organizations. The committee shall provide a project management manual that provides step-by-step guidance for organizations that carry out national R&D projects as a preventive measure against possible leakage. In the short term, the NIS National Industrial Security Center's duties should be expanded to incorporate national R&D projects' security. In the long term, a security task force must be set up to protect, support and manage the projects whose responsibilities should include research, policy development, PR and training of security-related issues. Through these means, a social consensus must be reached on the need for protecting national R&D projects. The most efficient way to implement these measures is to facilitate security training programs and meetings that provide opportunities for communication among industrial security experts and researchers. Furthermore, the Regulation's security provisions must be examined and improved.

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Studies on the Consumptine Use of Irrigated Water in Paddy Fields During the Growing of Rice Plants(III) (벼생유기간중의 논에서의 분석소비에 관한 연구(II))

  • 민병섭
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.11 no.4
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    • pp.1775-1782
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    • 1969
  • The results of the study on the consumptine use of irrigated water in paddy fields during the growing season of rice plants are summarized as follows. 1. Transpiration and evaporation from water surface. 1) Amount of transpiration of rice plant increases gradually after transplantation and suddenly increases in the head swelling period and reaches the peak between the end of the head swelling poriod and early period of heading and flowering. (the sixth period for early maturing variety, the seventh period for medium or late maturing varieties), then it decreases gradually after that, for early, medium and late maturing varieties. 2) In the transpiration of rice plants there is hardly any difference among varieties up to the fifth period, but the early maturing variety is the most vigorous in the sixth period, and the late maturing variety is more vigorous than others continuously after the seventh period. 3) The amount of transpiration of the sixth period for early maturing variety of the seventh period for medium and late maturing variety in which transpiration is the most vigorous, is 15% or 16% of the total amount of transpiration through all periods. 4) Transpiration of rice plants must be determined by using transpiration intensity as the standard coefficient of computation of amount of transpiration, because it originates in the physiological action.(Table 7) 5) Transpiration ratio of rice plants is approximately 450 to 480 6) Equations which are able to compute amount of transpiration of each variety up th the heading-flowering peried, in which the amount of transpiration of rice plants is the maximum in this study are as follows: Early maturing variety ; Y=0.658+1.088X Medium maturing variety ; Y=0.780+1.050X Late maturing variety ; Y=0.646+1.091X Y=amount of transpiration ; X=number of period. 7) As we know from figure 1 and 2, correlation between the amount evaporation from water surface in paddy fields and amount of transpiration shows high negative. 8) It is possible to calculate the amount of evaporation from the water surface in the paddy field for varieties used in this study on the base of ratio of it to amount of evaporation by atmometer(Table 11) and Table 10. Also the amount of evaporation from the water surface in the paddy field is to be computed by the following equations until the period in which it is the minimum quantity the sixth period for early maturing variety and the seventh period for medium or late maturing varieties. Early maturing variety ; Y=4.67-0.58X Medium maturing variety ; Y=4.70-0.59X Late maturing variety ; Y=4.71-0.59X Y=amount of evaporation from water surface in the paddy field X=number of period. 9) Changes in the amount of evapo-transpiration of each growing period have the same tendency as transpiration, and the maximum quantity of early maturing variety is in the sixth period and medium or late maturing varieties are in the seventh period. 10) The amount of evapo-transpiration can be calculated on the base of the evapo-transpiration intensity (Table 14) and Tablet 12, for varieties used in this study. Also, it is possible to compute it according to the following equations with in the period of maximum quantity. Early maturing variety ; Y=5.36+0.503X Medium maturing variety ; Y=5.41+0.456X Late maturing variety ; Y=5.80+0.494X Y=amount of evapo-transpiration. X=number of period. 11) Ratios of the total amount of evapo-transpiration to the total amount of evaporation by atmometer through all growing periods, are 1.23 for early maturing variety, 1.25 for medium maturing variety, 1.27 for late maturing variety, respectively. 12) Only air temperature shows high correlation in relation between amount of evapo-transpiration and climatic conditions from the viewpoint of Korean climatic conditions through all growing periods of rice plants. 2. Amount of percolation 1) The amount of percolation for computation of planning water requirment ought to depend on water holding dates. 3. Available rainfall 1) The available rainfall and its coefficient of each period during the growing season of paddy fields are shown in Table 8. 2) The ratio (available coefficient) of available rainfall to the amount of rainfall during the growing season of paddy fields seems to be from 65% to 75% as the standard in Korea. 3) Available rainfall during the growing season of paddy fields in the common year is estimated to be about 550 millimeters. 4. Effects to be influenced upon percolation by transpiration of rice plants. 1) The stronger absorbtive action is, the more the amount of percolation decreases, because absorbtive action of rice plant roots influence upon percolation(Table 21, Table 22) 2) In case of planting of rice plants, there are several entirely different changes in the amount of percolation in the forenoon, at night and in the afternoon during the growing season, that is, is the morning and at night, the amount of percolation increases gradually after transplantation to the peak in the end of July or the early part of August (wast or soil temperature is the highest), and it decreases gradually after that, neverthless, in the afternoon, it decreases gradually after transplantation to be at the minimum in the middle of August, and it increases gradually after that. 3) In spite of the increasing amount of transpiration, the amount of daytime percolation decreases gadually after transplantation and appears to suddenly decrease about head swelling dates or heading-flowering period, but it begins to increase suddenly at the end of August again. 4) Changs of amount of percolation during all growing periods show some variable phenomena, that is, amount of percolation decreases after the end of July, and it increases in end August again, also it decreases after that once more. This phenomena may be influenced complexly from water or soil temperature(night time and forenoon) as absorbtive action of rice plant roots. 5) Correlation between the amount of daytime percolation and the amount of transpiration shows high negative, amount of night percolation is influenced by water or soil temperature, but there is little no influence by transpiration. It is estimated that the amount of a daily percolation is more influenced by of other causes than transpiration. 6) Correlation between the amount of night percoe, lation and water or soil temp tureshows high positive, but there is not any correlation between the amount of forenoon percolation or afternoon percolation and water of soil temperature. 7) There is high positive correlation which is r=+0.8382 between the amount of daily percolation of planting pot of rice plant and amount and amount of daily percolation of non-planting pot. 8) The total amount of percolation through all growin. periods of rice plants may be influenced more from specific permeability of soil, water of soil temperature, and otheres than transpiration of rice plants.

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