본 연구는 해상풍력발전기에 추가적인 통신전용선로를 확보하지 않고도 자체 전력선을 이용하여 나셀의 상태를 감시할 수 있는 시스템을 구현하는 것을 목표로 한다. MW 급 해상풍력발전기의 내부 전력선을 훼손하지 않고도 통신선로를 확보하기 위하여 유도성 결합기 기반 비접촉식 무배선 통신시스템을 제안하고 성능시험 결과를 보고한다. 페라이트 복합물질을 이용하여 최대 500 A의 고 전류에도 동작할 수 있는 전력선 통신용 유도성 결합기를 개발하였으며 제주도 풍력단지에서 실증시험을 진행하였다. iperf를 이용한 통신성능시험에서 풍력발 전기 나셀부와 하단 기저부의 전력변환기간 100 m 길이의 전력선으로 최소 15 Mbps 이상의 통신 속도를 안정적으로 확보할 수 있음을 보였 다. 이를 바탕으로 1 주일간의 연속적인 통신상태 시험을 수행하였으며 평균 20 Mbps의 데이터 전송률을 확인하였다. 시험기간 동안 단한번 의 통신 불량도 발생하지 않았다. 다음으로 나셀 내부 온도 분포와 변화를 측정하기 위하여 적외선 카메라를 설치하였다. 카메라에서 획득한 실시간 열화상 이미지가 오류 없이 성공적으로 전송됨을 확인하였다.

In this study, we compared disease incidence rate and phyllosphere microbial community between drought resistance transgenic rice (Agb0103) and non-transgenic Ilmi (NGM) during 2011-2014 to examine an environmental risk assessment of drought resistance transgenic rice (Agb0103). As the results, major diseases such as sheath blight, brown spot, leaf blast and false smut were occurred, however, there were no significant disease incidence rate between Agb0103 and NGM. As the results of counting bacterial and fungal viable cell, the colonies were increased or decreased which affected by environmental conditions, however there were no differences between Agb0103 and NGM. Also unweighted pair-group method with arithmetic averaging (UPGMA) analysis based on polymerase chain reaction with denaturing gel electrophoresis (PCR-DGGE) revealed that DGGE band pattern of bacterial and fungal communities were clustered by each month and there were no differences between Agb0103 and NGM. Furthermore, isolated casual agents causing sheath blight and brown spot were collected from Agb0103 and NGM, and they revealed that each of pathogens were no differences in morphology and pathogenicity. Therefore, our results suggested that Agb0103 showed no differences in disease incidence rate, characteristic of pathogens and phyllosphere community with NGM. In this way, it can be assumed that transgenic rice Agb0103 could not influence phyllosphere microorganism community and environmental conditions.

The preaent study was conducted to investigate the effect of mixed seeding of three wheat variwties, ‘Anzunbaengimil’, ‘Jokyoung’, and ‘Sooan’, on agricultural characteristics and quality of plants to select the most suitable mixed seeding ratio. We observed that the yield of plants obtained from the mixed seeding combinations was higher than those obtained from single seeding of the three varieties. The yield was high, especially for the combinations ‘Sooan’ and ‘Anzunbaengimil’ (80 and 20%, respectively) and ‘Sooan’ and ‘Jokyoung’ (90 and 10%, respectively). The protein content of the seedlings obtained from the above two combinations was higher than in the seedling of ‘Sooan’. Based on our results, we suggest that mixed seeding of wheat varieties is more effective than single seeding in improving the yield and quality of plants obtained from mixed seeding.

Anther culture is useful and significant tool for producing haploid or doubled haploid (DH) plants in crop breeding system. Androgenesis is the way of inducing haploid and DH plants from anther (immature pollen) or microspore culture. In vitro androgenesis is efficient technique for introducing complete homozygous lines in one generation, thus less time and expense could be necessary than conventional plant breeding. In maize, anther culture is important system for shortening the breeding cycle and enhancing selection efficiency. Anther culture technique is also applicable to various researches such as molecular genetics, genetic engineering, genomics, and plant biotechnology. We review the past and present studies on anther culture and provide useful information for future researches on androgenesis in maize. The combination of androgenesis with other techniques such as molecular breeding and biotechnology is producing a variety of variety of maize species. In addition, we suggest strategy to develop androgenesis technique adapted to Korean research environment.

The thermal and mechanical properties of fiber-reinforced cement-based composite for solar thermal energy storage were investigated in this paper. The effect of the addition of different cement-based materials to Ordinary Portland cement on the thermal and mechanical characteristics of fiber-reinforced composite was investigated. Experiments were performed to measure mechanical properties including compressive strength before and after thermal cycling and split tensile strength, and to measure thermal properties including thermal conductivity and specific heat. Test results showed that the residual compressive strength of mixtures with OPC and slag was greatest among cement-based composite. Thermal conductivity of mixtures including graphite was greater than that of any other mixtures, indicating favor of graphite for improving thermal transfer in terms of charging and discharging in thermal energy storage system. The addition of CSA or zirconium increased specific heat of fiber-reinforced cement-based composite. Test results of this study could be actually used for the design of thermal energy storage system in concentrating solar power plants.