농업에서 거친 토양 표면은 다양한 문제를 일으킨다. 물, 토양, 씨앗, 비료와 같은 자원을 낭비하여 생산비를 높이고 환경에도 부정적인 영향을 끼친다. 또, 농업 기계는 거친 토양에서 균형을 잡기 어려워 농부들의 편의성을 해치고, 장비의 내구성과 자율 주행 성능을 떨어뜨리는 등 정밀농업의 실현을 방해한다. 거친 토양 표면은 입자가 큰 토양으로 구성되어 있을 가능성이 높으며, 이는 식물 생장을 방해하고 물빠짐에도 영향을 준다. 거친 표토를 측정하는 방식은 농지 전체를 측정하기보단 일부 지점의 거칠기를 측정하여 나머지 지점의 거칠기를 추정하는 것이 다수다. 따라서, 본 연구는 무인비행체(UAV)를 이용해 효율적으로 표토 거칠기를 측정할 수 있는 방안을 제안하고자 한다. 실험은 경상남도 밀양시 부북면에서 40m 높이에서 180장, 86%의 중첩률로 획득한 항공 사진을 이용했다. 이미지 데이터를 바탕으로 만들어진 조밀 점군에서 파이썬으로 중심점으로부터 일정한 반경 이내에 있는 가까운 주변 8개 점을 선택하여 고도차를 이용하여 결과값을 계산하였다. TRI 지수, Roughness 지수, 표준편차 세 가지 지표는 계산 후 농지에 시각화되었다. 일부 지점에서 측정한 표토 거칠기를 바탕으로 나머지 농지에 대한 거칠기 값을 추정하는 방식과 달리, 본 연구는 모든 지점에서의 거칠기 지수를 점군 단계에서 습득할 수 있는 방식을 통해 측정의 정밀도를 높이고 농지 운영을 돕고자 하였다.

Laser cutting has been attracting attention as a next-generation tool in application for nuclear decommissioning. It enables high-speed cutting of thick metal objects, and its narrow kerf width greatly reduces the amount of secondary waste compared to other cutting methods. In addition, it only requires the relatively small cutting head without any complicated equipment, and long-distance cutting apart from a laser generator is possible using beam delivery through optical fiber. And there is almost no reaction force because it is non-contact thermal cutting. For these reasons, the laser cutting is very advantageous for remote cutting. In laser cutting, the irradiated laser power is absorbed and consumed to melt the material of the cutting target. When the applied laser power is greater than the power consumed for melting, the residual power is transmitted to the back of the cut object. This residual power may unintentionally cut or damage undesired objects located behind the cutting target. In order to prevent this, it is necessary to adjust the laser power for each thickness of the target object to be cut, or to increase the distance between the cut target and the surrounding structures so that the transmitted power density can be sufficiently lowered. In this work, safety study on residual power that penetrates laser-cut objects was conducted. Experimental studies were performed to find safe conditions for irradiation power density that does not cause surface damage to the stainless steel by adjusting the laser power and stand-off distance from the target.

Enterotoxigenic Escherichia coli는 신생 및 이유기 돼지 설사의 주요 원인체로서 전세계적으로 양돈산업에 큰 경제적 손실을 끼치고 있다. 그러나 현재 국내에는 이러한 E. coli가 보유하는 다양한 병원성유전자의 분포 및 특성에 대한 정보가 부족한 실정이다. 이에 본 연구에서는 2013년부터 2016년까지 국내 163개 양돈농장에서 이유기 설사증 개체로부터 면봉스왑 샘플을 채취하여 동일 농장의 개체일 경우 5개에서 10개 정도를 혼합한 후, MacConkey agar에 배양하여 최종 API 32E system을 통하여 동정하였다. 분리된 모든 균주에 대해서 3가지의 다른 multiplex PCR을 수행하여 총 13종의 병원성유전자의 분포를 확인하였다. 이를 통하여 총 172개의 최소 한가지 이상의 병원성 유전자를 가지는 E. coli 균주를 확인하였고, 그 결과 병원성 유전자의 분포는 (1) fimbrial adhesins (43.0%): F4 (16.9%), F5 (4.1%), F6 (1.7%), F18 (21.5%), and F41 (3.5%); (2) toxins (90.1%): LT (19.2%), STa (20.9%), STb (25.6%), Stx2e (15.1%), EAST1 (48.3%); and (3) nonfimbrial adhesin (19.6%): EAE (14.0%), AIDA-1 (11.6%) and PAA (8.7%)로 나타났다. 결론적으로 본 연구결과는 국내 양돈농장의 이유기 설사증에 관연하는 E. coli는 다양한 종류의 병원성 유전자를 가지고 있으며 그러한 병원성 유전자의 조합도 매우 다양하게 분포하고 있음을 나타낸다.

Background : Glycyrrhiza uralensis Fischer is one of most important medicinal (Glycyrrhizae radix) herbs in traditional oriental medication and they are also important commercial products used worldwide in sweetening and flavoring. They contain the similar compounds, such as the triterpenoid saponins and flavonoids. Therefore, it is necessary to develop more efficient and sustainable methods for the production of G. uralensis Fischer and its medicinal constituents. This study was accomplished to investigate the effect of medium composition on in vitro propagation and plantlet regeneration from nodal explants of G. uralensis Fischer, and to establish a reliable protocol for micropropagation. Methods and Results : Young and actively growing stem segments were excised from adult plants of new cultivar ‘manju’. They were cut into a 1cm nodal segments with single node after sterilization, and cultivated in the different medium supplemented with various plant growth regulators for two weeks. For shoot multiplication, one-node stem segments, approximately 1 ㎝ in length, were taken from in vitro derived shoots and subcultured. After four weeks of culture, the efficacy of each medium on shoot proliferation and growth was determined, and these shoots were transferred onto medium with different auxin hormones for rooting. Conclusion : After seven to ten days of culture, shoots began to emerge from axillary buds. They showed a vigorous growth and elongation in multiplication medium. During culture period, in vitro cultured plantlets showed significantly different responses to the respective medium with different plant growth regulators. Our experiments confirmed that in vitro growth and multiplication of palntlets could depend on its reaction to the different medium composition, and this micropropagation techniques could be a useful system for healthy and vigorous plant production.

Background : Rehmannia glutinosa Libosch. is a perennial herb belonging to family Scrophulariaceae. It is also considered as a valuable medicinal plant in Asia including Korea, China and Japan because of its anti-anemic, anti-pyretic, anti-inflammatory and anti-senescence effects. Unfortunately it is difficult to propagate seeds due to poor seed viability and low propagation rate. Therefore, this plant is propagated vegetatively, but its vegetative propagation increases the incidence of virus infections in commercial fields, which can induce the production loss critically. So we have tried to compare the efficacy of virus elimination from R. glutinosa by thermotherapy, chemotherapy and shoot tip culture to find an optimal micropropagation for healthy and virus-free plant production. Methods and Results : For virus elimination, thermotherapy (heat treatment at 37℃ for 4 weeks), chemotherapy (addition into medium with antiviral agent) and shoot tip culture (meristem culture) were accomplished. After treatments, RT-PCR and ELISA methods were used for detection of three viruses including tobacco mosaic virus (TMV), cucumber mosaic virus (CMV), broad bean wilt virus (BBWV). Conclusion : Efficiency of virus elimination was enhanced up to 59% in shoot tip culture, however, lowest at 5 - 10% after chemotherapy using antiviral agent (ribavirin). Most samples were verified to have multiple virus infection. From these results, we can suggest that combination treatment of shoot tip culture and thermotherapy may be more effective for the elimination of major viruses from R. glutinosa.

Background: Leonurine is a the aerial part of Leonurus japonicus Houttuyn, which has been used as a traditional medicines and is registered in the Korean Pharmacopoeia.Methods and Results:In the present study we performed a heavy metals and thin layer chromatography and measured loss on drying, as well as the contents of total ash, acid-insoluble ash, ethanol soluble compounds, and leonurine, using 15 domestically collected L. japonicus samples. The methods were performed according to the ‘crude drugs test of the general test, processes and apparatus’, published by MFDS, Korea (2014). The purity test (heavy metals) indicated that levels of Pb and Hg were 0.35 - 3.64, and 0.001 ppm, respectively, whereas the levels of As and Cd were undetectable, and stachydrine was identified by thin layer chromatography (Rf : 0.15). We found that 5.93 - 10.62% (average: 8.58 ± 1.8%) of the sample mass was lost during drying, and the contents of total ash, acid-insoluble ash, ethanol soluble compounds, and leonurine were 7.87 - 10.84% (average: 9.62 ± 0.82%), 0.99 - 1.76% (average: 1.38 ± 0.24%), 16.70 - 23.11% (average: 19.49 ± 2.14%) and 0.04 - 0.17% (average: 0.11 ± 0.04%) respectively. In addition, HPLC profiling detected leonurine (5.94 min), rutin (16.43 min) and myricetin (26.78 min).Conclusions:We hope that this the rusult of the present study will contribute to the standardization and quality control of Korean herbal medicines.