• 한국유기농업학회지
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• 제16권4호
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• pp.435-453
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• 2008

유기농업에서 윤작은 중요하고, 윤작작부체계에는 반드시 두과작물이 포함되어야 한다. 대두재배 영농현장에서 근류균 접종을 토양접종으로 손쉽게 파종 전에 실시할 수 있겠으나, 유기농 토양조건에서 토양접종의 효과에 대한 검토가 필요하다. 본 실험은 토양의 근류균 접종이 대두의 근류 형성과 생육 및 수량에 미치는 영향을 알아보고자 천안시 입장면에 소재한 단국대학교 유기농업연구소 실습포장에서 대원콩, 신팔달콩2호, SS2-2을 공시하여 2006년도에 수행하였다. 토양의 근류균 접종에 따른 공시품종의 근류수는 무처리구보다 처리구가 $1.4{\sim}2$배 가량 많았다. 무처리구는 개화성기(R2)이후부터 근류형성이 감소하였으나 처리구는 착협성기(R4)까지 근류의 수가 증가하다 이후 감소하였다. 토양의 근류균 접종에 따른 공시품종 근류중량의 경시적 변화는 근류수의 경시적 변화와 같은 경향을 보였다. 대원콩은 처리구의 건물중이 무처리구보다 증가했지만 신팔달콩2호와 SS2-2는 무처리구보다 처리구의 건물중이 감소하였다. chlorophyll 함량은 대원콩의 경우 무처리구보다 처리구에서 9% 가량 높았으나, 신팔달2호콩과 SS2-2는 오히려 처리구에서 각각 13%, 33% 가량 낮았다. 토양의 근류균 접종에 따른 대원콩 협수, 립수, 립중은 처리구가 증가하였지만 신팔달 2 호콩과 SS2-2의 협수, 립수, 립중은 처리구가 오히려 감소하였다. 토양의 근류균 접종에 따른 10a당 수량은 대원콩은 처리구가 13% 증가하였으나 신팔달2호콩은 처리구가 4% 감소하였고, SS2-2도 처리구가 23% 감소하였다.

• Bulletin of the Korean Chemical Society
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• 제30권5호
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• pp.1031-1034
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• 2009

Fluorescence of quinolones including norfloxacin, ciprofloxacin and S- and R-ofloxacin is quenched upon association with single and double-stranded DNA (ss- and ds-DNA). The ratios of fluorescence intensity in the presence of DNA to its absent were plotted with respect to the DNA concentration to construct the Stern-Volmer plot. The slope of the Stern-Volmer plot become larger as the temperature is lowered, ensuring that the fluorescence quenching is static process, i.e., the fluorescence is quenched by formation of the non-fluorescent complex between quinolone and DNA. In the static quenching mechanism, the quenching constant which is equivalent to the slope of the Stern-Volmer plot, is considered as the equilibrium constant for the association of quinolones and DNA. From the temperature-dependent equilibrium constant, ${\Delta}H^0\;and\;{\Delta}S^0$ was obtained using the van’t Hoff relation. In general, association of the quinolone with ds- as well as ss-DNA is energetically favorable (an exothermic) process while the entropy change was unfavorable. Due to the steric effect of the substituents, the effect of the quinolone ring is smaller on the ss-DNA compared to ds-DNA.

• 한국농공학회논문집
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• 제54권4호
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• pp.19-27
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• 2012

The objective of this study was to test the pollutant reduction effect by the silt fence and vegetated ridge through field monitoring. The experiment plots were established with two replication and three treatments. Each plot was designed with 5 m width, 22 m length, and 3 % slope. Flumes with the floating type stage gages were installed at the outlet of each plot to monitor the runoff. For a rainfall monitoring, tipping bucket rain gage was installed within the experiment site. Cultivated crops were spring daikon and autumn chinese cabbage. Analysis of variance (ANOVA) indicated that the water quality concentration from three experiment plots were not significantly different in 5 % of significant level. The monitoring results showed that the average pollution loads reduced by silt fence compared to control were SS 75.33 %, TN 40.87 %, TP 56.58 %, BOD 52.12 %, COD 36.07 %, TOC 34.99 %; by vegetated ridge compard to control were SS 65.27 %, TN 81.80 %, TP 54.26 %, BOD 67.09 %, COD 46.55 %, TOC 43.30 %. Analysis of Spearman's rank correlation coefficient showed that BOD-SS and SS-Turbidity were highly related at the silt fence and vegetated ridge plots. In all plots, SS-Turbidity and TP-TN relations were relatively high. The monitoring results showed that the silt fence and vegetated ridge were effect method to reduce the pollutant loads from the field runoff. Long-term monitoring is required to obtain more quantitative reduction effect for diverse crops and to increase the reliability of results.

• 한국물환경학회지
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• 제28권3호
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• pp.436-443
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• 2012

This research was focused on the effect of rice straw and rice straw mat on the reduction of upland field non-point source (NPS) pollution discharges. Six experimental plots of $5{\times}22m$ in size and 3% in slope prepared on gravelly sandy loam soil were treated with control, rice straw cover and rice straw mat cover. Radish in Spring growing seasons were cultivated. NPS pollution discharge was monitored and compared with respect to the treatments. The surface cover rate of rice straw and rice straw mat right after the treatments was 64.7% and 73.7%, respectively. Rainfall of the 16 monitored events ranged from 12.8 mm to 538.2 mm. Runoff coefficient of the events was 0.01~0.67 in control plot, 0~0.63 in rice straw plot and 0~0.45 in rice straw mat plot. The reduction of runoff compared to the control plot was 5.4~99.7% in rice straw plot and 32.9~100% in rice straw mat plot. The reduction of NPS pollution load was 52.0% for SS, 28.5% for T-N and 35.2% for T-P in rice straw plot and 79.8% for SS, 68.3% for T-N and 53.3% for T-P in rice straw mat plot. This research revealed that rice straw mat cover on the soil surface could not only increase the crop yield and farmer's income but also reduce the NPS pollution loads significantly.

• 한국농공학회논문집
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• 제55권4호
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• pp.21-28
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• 2013

The objective of the study was to investigate the effect of rice straw mat, rice straw mat with PAM (Polyacrylamide) and gypsum addition on surface runoff and sediment discharge in field. Six experimental plots of $5{\times}22m$ in size and 3 % in slope prepared on gravelly sandy loam soil were treated with control, rice straw mat cover with gypsum and rice straw mat cover with gypsum and PAM. Radish in Spring and Chinese cabbage in autumn growing seasons were cultivated. Non point source (NPS) pollution discharge was monitored and compared among the treatments. Rainfall of the 10 monitored events ranged from 17.0 mm to 93.5 mm. Runoff coefficient of the events was 0.005~0.239 in control plot, 0~0.176 in rice straw plot with gypsum and 0~0.046 in rice straw mat plot with gypsum and PAM. When compared to the control plot, the runoff amount was reduced by 10.4~100 % (Ave. 60.8) in rice straw plot with gypsum and 80.7~100 % (Ave. 96.7 %) in rice straw mat plot with gypsum and PAM. The reduction of NPS pollution load was 54.6 % for BOD5, 71.5 % for SS, 41.6 % for TN and 61.4 % for T-P in rice straw with gypsum plot and 91.9 % for BOD5, 92.0 % for SS, 88.0 % for TN and 88.5 % for T-P in rice straw mat with gypsum and PAM plot. This research revealed that rice straw mat cover with soil amendments on the soil surface could not only increase the crop yield but also reduce the NPS pollution loads substantially.

• 소성∙가공
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• 제6권6호
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• pp.471-481
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• 1997

This paper is concerned with the kinematic analysis of several linkage drives for mechanical presses. Load and velocity characteristics of conventional presses are illustrated and a design of new drive for a mechanical press is represented. In this regard, a crank-slider mechanism with arc crank-pin guide is introduced and compared with other linkage drives. Kinematic performances are analyzed in respect of load capacity, slide velocity characteristics using a developed SS-Plot program. The new linkage drive turns out to be effective in terms of load and velocity characteristics, and productivity.

• 한국관개배수논문집
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• 제18권1호
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• pp.94-102
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• 2011

The aim of this study was to evaluate the load of non-point sources pollutant at a paddy plot located at the valley watershed during irrigation period. Irrigation, runoff and water quality data in the paddy plot were analyzed periodically from June 1 to October 31 in 2005. The observed amount of precipitation, irrigation, runoff for the experimental paddy plot during the irrigation period was 1,297.8, 223.2, and 825.4mm, respectively. Total-N concentrations ranged from 3.73 to 18.10mg/L, which was generally higher than the quality standard of agricultural water (1.0mg/L). Total-P concentrations ranged from 0.111 to 0.243mg/L and the average was 0.139mg/L. The observed runoff pollutants loadings from the paddy plot were measured as 34.4 kg/ha for T-N, 1.0 kg/ha for T-P and 213.8 kg/ha for SS. The non-point sources pollutant load in drainage water depends on rainfall and surface drainage water amount from the paddy plot. We are considering that these results were affected by rainfall as well as hydrological condition, soil management, whether or not fertilizer application, cropping, rice straw and plowing.

• 한국축산시설환경학회지
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• 제16권3호
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• pp.215-226
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• 2010

본 연구는 목편살수여상 pilot 장치를 설치하여 스크레파 축사에서 배출되는 뇨오수를 원수로 사용하여 가동한 후 침출액비를 공시재료로 하여 상추 양액재배 시험을 실시하였다. 처리구는 침출액비 (SL) 단독처리구, 침출 액비+어분 (SL+FM), 침출액비+골분 (SL+BM), 침출액비+게껍질 (SL+CS) 혼합처리구. 침출 액비+부산물 (SL+FM+BM+CS) 혼합처리구, 대조구로 원예연 상추양액 (NS) 처리구 등 6개 처리구를 두었다. 침출액비와 부산물 혼합처리 후 전기전도도와 pH를 조정하여 상추의 양액재배를 실시한 결과를 요약하면 다음과 같다. 1. 목편살수여상 처리 과정중 pH는 처리 시작전 7.3에서 처리 후 8.5로 상승하였다. 전기전도도 (EC)는 처리전 17.05 mS/cm에서 처리 후 30일에는 9.7 mS/cm로 낮아졌다. 2. 침출액비는 부유물질 (SS)이 낮아 수경 재배시 관배수의 막힘문제 없이 활용이 가능하였다. 침출액비는 양분조성에서 칼륨함량이 높고 인산 함량이 낮았다. 3. 침출액비시용구 (SL)의 상추수량은 원예 연 표준양액재배 대비 75%를 나타내어 25% 수량저하를 나타내었다. 침출액비을 어분. 골분. 게껍질을 혼합한 처리구는 대조구 대비 85%. 79%. 80% 수량을 나타내어 어분의 첨가 효과가 가장 높았다. 침출액비와 어분 혼합액은 침출액비 단독처리구 보다 10% 증수를 나타내어 유기양액의 대체 원료로 사용이 가능 할 것으로 보인다.

• 지질공학
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• 제20권4호
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• pp.401-407
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• 2010

농업지역에서 발생한 오염부하량을 결정하기 위해 여러 토지이용형태 중에서 벚나무 재배지(단위 비점오염원)에서 발생하는 오염부하 특성을 조사하였다. 유출시 발생된 강우사상에서는 강우량과 유출수량의 상관계수가 0.5로 낮게 나타나 투수성을 예측할 수 없는 수준이었다. 강우량 20mm 미만인 경우에도 강우강도가 8.8 mm/hr 수준으로 높은 경우에는 유출이 발생하였으나 강우량이 47.4 mm로 많은 경우라 할지라도 긴 무강우일수와 약한 강우강도를 보인 경우에는 유출이 발생하지 않았다. 강우사상시 발생된 유출량과 SS, BOD, COD, TN 및 TP 오염부하량과의 상관계수는 SS에서 최저값 0.71을 보인 것 이외에는 모두 r ${\geq}$ 0.92로 매우 유의한 값을 나타냈다. 한편 SS와 다른 오염물질간의 오염부하상관성도 모두 r ${\geq}$ 0.73의로 유의한 값을 나타내었으므로 SS관리를 통해 유기물질과 영양염에 대한 제어도 가능함을 알 수 있다. 최고 TN농도는 시비활동에 의해 직접적 영향을 받은 Event의 유출수에서 발생하였다. 따라서 농경지에서 발생하는 유출수의 오염수준을 평가할 때에는 시비여부를 반드시 고려해야 할 것이다.

• 한국농공학회논문집
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• 제56권3호
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• pp.47-53
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• 2014

We investigated the effect of straw mat cover and soil amendments on the reduction of runoff, non-point source pollution load and yield of a Chinese cabbage from alpine fields. Two plots on sandy loam soil were prepared. Experimental treatments were control and rice straw mat cover (3,300 kg/ha)+Polyacrylamide (PAM) (5 kg/ha)+Gypsum (1 ton/ha) (SPG). A variety of Chinese cabbage was cultivated and runoff was monitored during a growing season in 2012. Monitoring was conducted to seven times. Runoff rate of SPG plot was lower than those of control plot. The reduction rate of runoff from SPG plot was 29.4 % compared to control plot. The reduction rate of suspended solids (SS), total nitrogen (TN) and total phosphorus (TP) load of SPG plot was 86.5 %, 34.7 % and 39.1 %, respectively. Yield of a Chinese cabbage from SPG plot (39,646 kg/ha) was greater than that of control plots (28,482 kg/ha). It was concluded that the use of SPG on soil surface could not only reduce the NPS pollution loads in receiving waters but also help increase the crop yield.