농업용수 수질기준의 문제점 및 개선대책 : 외국사례와의 비교를 통해

김진호,이종식,정구복,윤순강,고문환,심재천,권순국 한국국제농업개발학회 2003 韓國國際農業開發學會誌 Vol.15 No.3

우리나라 농업용수 수질기준과 다른 국가 또는 농업관련 국제기구의 수질기준에 대한 비교분석을 통해 우리나라 농업용수 수질기준의 문제점 도출과 해결방안을 모색코자 본 연구를 수행하게 되었으며, 그 결과를 요약하면 다음과 같다. 1. 우리나라 농업용수 수질기준은 관개용수 수질기준이 아니고, 수원보호측면의 수질기준이라 할 수 있다. 2. 우리나라 수질기준중 유기물지표가 하천과 호소에 따라 BOD와 COD로 이원화되어 있고, 특히 COD의 경우 산화제로 KMnO4를 사용함으로써 효과적인 유기물지표로 활용할 수 없는 실정이다. 농업용수로의 활용측면에서는 K₂Cr₂O_(7)을 이용한 COD를 기준으로 도입하는 것이 유기물 분해능 및 수중의 유기물지표로 활용하고 있는 국제적 데이터 일치를 위해서도 타당하다. 3. 우리나라 농업용수 수질기준은 캐나다와 FAO에서 제시하고 있는 염류에 대한 기준은 거의 없는 실정이다. 또한 양이온에 대한 기준도 없다. 염류의 기준이 모든 이온 존재의 가능성을 의미하므로, 실험치 및 외국문헌에 의한 1.0dS/m수준을 한계농도로 선정해야 한다. 4. FAO와 캐나다에서 사용하고 있는 축산용수에 대한 수질기준이 없다. 5. 관개용 농업용수가 농업(작물)에 미칠 수 있는 영향을 평가하기 위해서는 수원별로 수질기준이 다른 것이 큰 모순이다. 따라서 관계부처에서는 부처간의 이해를 떠난 수질기준을 설정해야 한다. 6. 우리나라 농업용수 수질기준의 모순점을 극복하기 위해서는 농업의 안전성확보측면 위해 관개용수 수질기준과 축산용수 수질기준을 조속히 제정해야 할 것이다. Present problems and possible solutions on the Water Quality Standards for Agriculture in Korea, were identified in the study. Because the Ministry of Environment made the laws and standards without consulting the agri-scientists, among others, the water quality standards formulated were not suitable standards of FAO, Japan, Canada, and the likes. The BOD and COD are the organic materials indicators. In case of rivers, BOD are set for the indicator. And at reservoirs. COD are set. Especially. COD was analysed using KMnO₄It is not suitable oxidizing agent for COD. Because the oxidic capacity is very low. So, in most developed country, K₂Cr₂O_(7) is usually used to analyze COD. And the salts and cations are not belonged to the Korean Water Quality Standards for Agriculture. The water quality standards for agriculture have big differences among lakes, rivers and groundwater. To apply different standards by resources to evaluate the relationship between water and crops is conflicting. So, to overcome the these problems, the suitable water quality standards for irrigation and livestock should be set.

우리나라 논 관개용 지하수 수질 특성

김진호,조광래,임수정,이경자,경기천,엄미정,김희권,김찬용,이영한,이신찬,윤순강 한국환경농학회 2003 한국환경농학회지 Vol.22 No.4

This study was carried out to evaluate the status of the groundwater quality for paddy fields irrigation in Korea. Water samples were collected at 130 sites throughout the country. Samples were collected at three seasons-April, July and October-in 2000. According to our survey, the groundwater was found to be suitable for irrigation purpose. Average EC was shown 0.286 dS/m. Nitrate-nitrogen and Cl^(-) concentration was 5.6 ㎎/L, 32.95 ㎎/L which satisfied the Korean Standards for Irrigation Water. Nitrate-nitrogen concentration in each province was shown as following orders: Jeju (11.17 ㎎/L) > Chungnam (8.16 ㎎/L) > Gyeongbuk (6.64 ㎎/L) > Gyounggi (5.91 ㎎/L) > Chungnam (4.95 ㎎/L) > Gyeongnam (3.91 mgk) > Jeonbuk (3.50 ㎎/L) > Jeonnam (3.27 ㎎/L) > Gangwon (2.91 ㎎/L). The concentration by sampling seasons were October (6.62 ㎎/L) > July (5.88 mg&) > April (4.78㎎/L). As the soil of Jeju Province is usually derived from volcanic ash soils mainly used for upland drops, it may influence the nitrate-nitrogen concentration of groundwater. The amount of rainfall also influence the water quality. But the COD_(Cr), were shown April (3.17㎎/L) > July (2.91 ㎎/L) > October (2.40 ㎎/L), it is highly related in the basal dose of organic matter fertilizers. This study demonstrated that groundwater quality was suitable for irrigation, but continuous monitoring is recommended for agricultural policy and developing OECD agricultural environment indicators.

Tip Position Control of a Flexible-Link Manipulator with Neural Networks

Yuan-Gang Tang,Fu-Chun Sun,Zeng-Qi Sun,Ting-Liang Hu 대한전기학회 2006 International Journal of Control, Automation, and Vol.4 No.3

To control the tip position of a flexible-link manipulator;a neural network (NN) controller is proposed in this paper. The dynamics error used to construct NN controller is derived based on output redefinition approach. Without the filtered tracking en-or;the proposed NN controller can still guarantee the closed-loop system uniformly asymptotically stable as well as NN weights bounded. Furthermore;the tracking error of desired trajectory can converge to zero with the proposed controller. For comparison an NN controller with filtered tracking en-or is also designed for the flexible-link manipulator. Finally;simulation studies are carried out to verify the theoretic results.

S-결장경 검사시 PEG-ELS와 고전적인 대장 전처치법의 비교연구

오선의,최형우,황혜헌,전호열,김일식,최광석 대한가정의학회 1995 Korean Journal of Family Medicine Vol.16 No.11

Study on an Optimal Control Method for Energy Injection Resonant AC/AC High Frequency Converters

Yu-Gang Su,Xin Dai,Zhi-Hui Wang,Chun-Sen Tang,Yue Sun 전력전자학회 2013 JOURNAL OF POWER ELECTRONICS Vol.13 No.2

In energy injection resonant AC-AC converters, due to the low frequency effect of the AC input envelope and the low energy injection losses requirement, the constant and steady control of the high frequency AC output envelope is still a problem that has not been solved very well. With the aid of system modeling, this paper analyzes the mechanism of the envelope pit on the resonant AC current. The computing methods for the critical damping point, the falling time and the bottom value of the envelope pit are presented as well. Furthermore, this paper concludes the stability precondition of the system AC output. Accordingly, an optimal control method for the AC output envelope is put forward based on the envelope prediction model. This control method can predict system responses dynamically under different series of control decisions. In addition, this control method can select best series of control decisions to make the AC output envelope stable and constant. Simulation and experimental results for a contactless power transfer system verify the control method.

신.재생에너지 설비의 설계 및 시공기준 제정 연구

강용혁(Gang, Yong-Hyeok),장문석(Jang, Mun-Seok),백남춘(Baek, Nam-Chun),유권종(Yu, Gwon-Jong),박완순(Park, Wan-Sun),신현준(Sin, Hyeon-Jun) 한국신재생에너지학회 2005 한국신재생에너지학회 학술대회논문집 Vol.2005 No.11

본 신 재생에너지설비 시공 및 설치확인 기준 연구는 신재생에너지 시스템의 효율적인 보급과 사후관리 비용 절감 및 성능향상으로 인한 에너지 생산을 효과적으로 할 수 있게 될 뿐 만 아니라 보급확대를 위해서는 필수적으로 있어야 할 기준이다. 현재 보급사업으로 추진되고 있는 5개 에너지원에 대한 설비 시공 및 설치확인 기준을 작성하여 보급사업의 지침서 역할을 하도록 하였다. - 태양열 시스템 시공 및 설치확인 기준 개발 - 지열이용 시스템 시공 및 설치확인 기준 개발 - 태양광발전 시스템 시공 및 설치확인 기준 개발 - 풍력발전 시스템 시공 및 설치확인 기준 개발 - 소수력발전 시스템 시공 및 설치확인 기준 개발

Study on an Optimal Control Method for Energy Injection Resonant AC/AC High Frequency Converters

Su, Yu-Gang,Dai, Xin,Wang, Zhi-Hui,Tang, Chun-Sen,Sun, Yue The Korean Institute of Power Electronics 2013 JOURNAL OF POWER ELECTRONICS Vol.13 No.2

In energy injection resonant AC-AC converters, due to the low frequency effect of the AC input envelope and the low energy injection losses requirement, the constant and steady control of the high frequency AC output envelope is still a problem that has not been solved very well. With the aid of system modeling, this paper analyzes the mechanism of the envelope pit on the resonant AC current. The computing methods for the critical damping point, the falling time and the bottom value of the envelope pit are presented as well. Furthermore, this paper concludes the stability precondition of the system AC output. Accordingly, an optimal control method for the AC output envelope is put forward based on the envelope prediction model. This control method can predict system responses dynamically under different series of control decisions. In addition, this control method can select best series of control decisions to make the AC output envelope stable and constant. Simulation and experimental results for a contactless power transfer system verify the control method.

카바이트 처리에 따른 떫은감 "도근조생"의 과실 연화 및 품질

배강순 ( Bae Gang Sun ),김호철 ( Kim Ho Cheol ),김태춘 ( Kim Tae Chun ) 원광대학교 생명자원과학연구소 2003 생명자원과학연구 Vol.25 No.-

Curcumin derivative HBC induces autophagy through activating AMPK signal in A549 cancer cells

Guang-Zhou Zhou,Gang-Chun Sun,Shuai-Na Zhang 대한독성 유전단백체 학회 2015 Molecular & cellular toxicology Vol.11 No.1

Curcumin exhibits growth-suppressive activity against a variety of cancer cells, but low bioavailability restricts its application in chemotherapeutic trials. A synthetic curcumin derivative hydrazinobenzoylcurcumin (HBC) had been indicated that it could inhibit cell growth in A549 lung cancer cells via cell autophagy in our previous report. The present research aims to investigate the effect of HBC on the AMP-activated protein kinase (AMPK) signaling and whether AMPK signaling is involved in HBC-induced autophagy in A549 cells. The autophagy inhibitor 3-MA was used to block the inhibitory effect of HBC on the growth of A549 cells by acridine orange assay. The phosphorylations of AMPK and its downstream factor Acetyl CoA Carboxylase (ACC) were characterized in HBCtreated A549 cells with western blot analysis. Moreover, pharmacological inhibition of the AMPK signaling pathway by Compound C impairs the autophagyinducing effect of HBC. Our data indicates that HBC could activate the AMPK signal and induce AMPKmediated autophagy, which plays an important role in the inhibiting effect of HBC in A549 cells.

Effects of orthodontic mini-implant position in the dragon helix appliance on tooth displacement and stress distribution

Min-Ji Kim,Sun-Hyung Park,Hyeon-Seong Kim,Sung-Seo Mo,Sang-Jin Sung,Gang-Won Jang,Youn-Sic Chun 대한치과교정학회 2011 대한치과교정학회지 Vol.41 No.3

Objective: The purpose of this study was to investigate the stress distribution on the orthodontic mini-implant (OMI) surface and periodontal ligament of the maxillary first and second molars as well as the tooth displacement according to the OMI position in the dragon helix appliance during scissors-bite correction. Methods: OMIs were placed at two maxillary positions, between the first and the second premolars (group 1) and between the second premolar and the first molar (group 2). The stress distribution area (SDA) was analyzed by three-dimensional finite element analysis. Results: The maximal SDA of the OMI did not differ between the groups. It was located at the cervical area and palatal root apex of the maxillary first molar in groups 1 and 2, respectively, indicating less tipping in group 2. The minimal SDA was located at the root and furcation area of the maxillary second molar in groups 1 and 2, respectively, indicating greater palatal crown displacement in group 2. Conclusions: Placement of the OMI between the maxillary second premolar and the maxillary first molar to serve as an indirect anchor in the dragon helix appliance minimizes anchorage loss while maximizing the effect on scissors-bite correction.