수박과 참외를 1995년 6월 1일에 파종하여 6월 7일에 pot에 가식한 후 6월 24일에 greenhouse에 정식하여 2개월 20일 동안 재배하였으며, 이 재배기간 동안 원적외선 방사 bioceramics를 기비와 엽면 살포하는 방법으로 처리하여 다음과 같은 결과를 얻었다. 1. 참외와 수박 모두 생장 초기에는 엽면적 생장에 bioceramic 효과가 없었으나, 정식 20일이 지난 후부터 그 효과가 나타났으며, 참외의 경우에는 처리구 No. 2에서, 수박의 경우에는 처리구 No. 3에서 그 효과가 가장 크게 나타났다. 2. 수박 열매의 bioceramic 효과는 착과 후 초기부터 나타났으며, 중기에 약간 저조하다가 수확 직전인 후기에 그 효과가 두드러지게 나타났고, 처리구 No. 3에서 열매 생장률이 가장 크게 나타났다. 참외의 경우에는 착과 후 초기에 열매 성장률이 가장 컸으며, 중기, 후기로 갈수록 열매 성장률이 점차 감소하는 경향을 보였고, 처리구 No. 3에서 bioceramic 효과가 가장 크게 나타났다. 3. 참외 밀도에 대한 bioceramic 효과는 처리구 No. 3에서 가장 크게 나타났으나, 물보다 적은 0.975g/ cm2였고, 수박 밀도에 대한 bioceramic 효과는 처리구 No. 3과 No. 4에서 크게 나타났으며, 물보다 큰 1.031 1.035g/ cm2였다. 4. 참외와 수박의 경우 모두 처리구 No. 3에서 당도가 가장 높게 나타났으며, 참외는 Brix 당도계로 12.3이었고, 수박은 11.5였다. 5. 수확 10일 후 참외 열매의 신선도는 처리구 No. 2에서 가장 높게 나타났다. 수박의 경우는 수확 후 50일이 경과하여도 처리구 No. 4의 경우에는 신선도가 100% 유지된 것으로 보아 수박 재배 기간 중 bioceramic 처리가 적절하면 50일 정도의 저장이 가능할 것으로 판단되었다.

To use effectively the solar energy in greenhouse heating, a high performance solar collector should be developed. And then the size of the solar collector and thermal storage tank should be determined through the calculation of heating load. The solar collector must be set in the optimum tilt angle and direction to take daily solar radiation maximally, and the flow rate of heat transfer fluid through the solar collector should be kept in the optimum range. In this research, the performance tests of a capillary tube solar collector were performed to determine the optimum water flow rate and the results summarized as follows. 1. The regressive equations for efficiency estimations of the capillary tube solar collector in the open loop were modeled in the water flow rate of 700-l,000 l/hr. 2. The optimum water flow rate of the solar collector was estimated by the second order polynomial regression and the maximum efficiency was 80% at the water flow rate of 850 l/hr. 3. The solar thermal storage system consisted of a capillary tube solar collector and a water storage tank was tested at the water flow rate of 850 l/hr in the closed loop, and obtained the solar thermal storage efficiency of 55.2%. 4. As the capillary tube solar collector engaged in this experiment was made of non-corrosive polyolefin tubes, its weight was as light as 1/30 of the flat plate solar collector made of copper tubes. Therefore it was considered to be suitable for the greenhouse heating system.

The aim of our study was to provide a basic data for the development of a small greenhouse model suitable for urban farmers. The study analyzed installation inclination, positive and negative reasons for installation, location of installation, preferred crops in small greenhouses, plans for use of products, and expected effects by using small greenhouse. Positive opinion on small greenhouse installation was 80.4% of the survey respondents. The most positive reason for the installation of small greenhouses was fresh and safe food supply, and the negative reason was maintenance difficulties. The results obtained in our survey indicated that small greenhouses were more likely to be installed near the house, and urban farmers tended to grow organic leafy vegetables in soil. The expected benefits of small greenhouse operation were largely divided into ‘benefit for the improvement of the quality of life’ and ‘benefit for economic profits’, and expectation for the improvement of the quality of life was higher than economic benefit. As a result of the Likert 5-point scale analysis, ‘benefit for the improvement of the quality of life’ by using a small greenhouse was graded as high as 4.17∼4.60. On the other hand, the ‘benefit to economic profits’ was rated as low as 3.51∼4.14.

This study was attempted to evaluate the change of microbial community in inoculums, lag, and stationary phase using the community level physiological profiles (CLPP) base on C-substrate utilization. It was to ascertain the characterizing microbial community over time in the enrichment step of microbial fuel cells. Microbial fuel cell is a device that converts chemical energy to electricity with aid of the catalytic reaction of microorganisms using C-substrate included wastewater. Microbial fuel cells enriched by a mixture of anaerobic digestive sludge of the sewage treatment plant and livestock wastewater were used. The current after enrichment was generated about 0.84 ± 0.06 mA. Microbial community in inoculums, lag and stationary phase used amine group, phosphorylated chemical group, and carboxylic acid group (some exclusion). However, phenolic compound did not use by microorganisms in lag and stationary phase. It means that there are not the microorganisms capable of decompose the phenol in microbial fuel cell enriched by livestock wastewater. In case of substrates of amino acid and carbohydrates group, these C-substrates were only used by microorganisms in the stationary phase. It may be that electrochemically active microorganisms (EAM) which we want to know should utilize the better these C-substrates than that of lag phase. This study showed that the electrochemically active bacteria that can be distinguished by electron changes of C-substrate utilization over time could be separated.