• Journal of Bio-Environment Control
• /
• v.20 no.2
• /
• pp.78-82
• /
• 2011

Ventilation rates, inside and outside weather data were measured in a arch-shape single-span plastic greenhouse growing tomatoes. On the roof of the experimental greenhouse, round windows which have a diameter of 0.6 m were installed at intervals of 8m. It showed that the number of air changes in this greenhouse were average 0.17 volumes per minute and in the range of 0.02 to 0.32 volumes per minute. These air changes are insufficient to meet the recommended ventilation rate for commercial greenhouses, and it is estimated that interval of 6 m is appropriate for spring or fall season. For summer season, it is necessary to narrow the space or to enlarge the open area of roof windows. Using the heat balance model, the evapotranspiration coefficients of greenhouse tomatoes were estimated from experimental ventilation data, overall heat transfer and solar radiation. It showed that the evapotranspiration coefficients were average 0.62 and in the 0.39 to 0.85 range. We suggest applying 0.6 as the evapotranspiration coefficient in design of ventilation for the single-span tomato greenhouses.

• Korean Journal of Soil Science and Fertilizer
• /
• v.25 no.4
• /
• pp.401-406
• /
• 1992

Antifungal substances against three plant pathogenic fungi, Phytophthora capsici, Phytophthora nicotianae var. parasitica and Rhizoctionaia solani were fractionated cultures of Streptomyces sp. A-2 strain isolated in Korean soils. Characterizations of active substances related with antagonistic effects were follows : 1. The excellent media which showed the transfer efficiency of antagonistic substances from Streptomyces sp. A-2 strain G.Y.B and B.H.I. among four that are glucose yeast broth (G.Y.B), $M\ddot{u}eller$, brain heart infusion(B.H.I.) and Czapek media. Active substances which were transfered into ethylacetate or left in residual aqueous phase did not lose antagonistic activity in spite of autoclavation. This indicated that bonds of these compounds were rigid enough to keep activity under such conditions. 2. Antagonistic substances were extracted according to adjustment of pH 3 or pH12 to 5 day-old B.H.I. broth cultures of Streptomyces sp. A-2 strain. Comparative analysis fluorescent bands on HPTLC to antagonsitic spectra against three phytopathogenic fungi indicated that major substances with antagonistic activity were extracted regardless of different pH adjustment to broth cultures. Since UV spectrum of these fractions scanned from 500nm to 200nm was similiar to that of polyene macrolide, major substances related with antagonistic activities were assumed to be polyene derivatives antibiotics.

• Korean Journal of Soil Science and Fertilizer
• /
• v.25 no.4
• /
• pp.387-393
• /
• 1992

The fate of inoculum strain of Bradyrhizobium japonicum was studied by using genetically marked strain. RJB6 $str^rnal^rneo^r$. A spontaneous mutant of B. japonicum isolated from nodules was made to have antibiotic resistance against streptomycin and nalidixic acid. In order to make genetically marked strain, neomycine resistant gene(Tn5) was introduced into this spontaneous mutant by conjugation with E. coli containing pSUP2021. The southern hybridization was carried out to confirm the plasmid insertion. Hybridization of chromosome DNA using pSUP2021(Tn5) as a probe showed that Tn5 was located on the 4.9kb fragment of chromosome. Soybean seeds were planted into a soil previously cultivated with soybean and inoculated with different cell densities of marked strain. Fourty days after planting, the inoculation effects on nodule number, nodule fresh weight, plant height and nitrogen content in the plot inoculated with heavy cell suspension was a little better than those in the plot with low inoculation. The recovery percentage of the marked strains was about 12% in the plot inoculated with heavy density cell suspension, while 5% in the plot inoculated with low cell suspension.

• Journal of Energy Engineering
• /
• v.24 no.3
• /
• pp.150-163
• /
• 2015

Gasification technology is one of the representative next-generation fossil fuel utilization technologies, converting low grade fossil fuels such as coal, heavy residue oil, pet-coke into highly clean and efficient energy sources. Accordingly, related market demand for gasification technology is ever increasing steadily and rapidly. A few years ago, conventional pulverized coal utilization technology had an edge over the gasification technology but the most significant technical barrier of limited capacity and availability has been largely overcome nowadays. Futhermore, it will be more competitive in the future with the advancement of related technologies such as gas turbine, ion transfer membrane and so on. China has recently completed a commercialization-capable large-scale coal gasification technology for its domestic market expansion and foreign export, rapidly becoming a newcomer in the field and competing with existing US and EU technical leadership at comparable terms. Techno-economic aspect deserves intensive attention and steady R&D efforts need to continue in organized, considering that gasification technology is quite attractive combined with $CO_2$ capture process and coal to SNG plant is economically viable in Korea where natural gas is very expensive. In the present paper, recent technology development and commercialization trend of many leading companies with coal gasification expertise have been reviewed with significant portion of literature cited from the recently held '2014 Gasification Technology Conference'.

• Horticultural Science & Technology
• /
• v.29 no.6
• /
• pp.592-599
• /
• 2011

Plum is a climacteric fruit and softening is a serious problem for storage and transportation. Thus $1{\mu}L{\cdot}L^{-1}$ of 1-methylcyclopropene (1-MCP) was applied to plums to prolong their shelf life and maintain quality. Japanese plums (Prunus salicina cv. Formosa) were stored at $20^{\circ}C$ and $0^{\circ}C$ for 14 days and 46 days respectively, with or without 1-MCP treatment. Fruits were treated with $1{\mu}L{\cdot}L^{-1}$ 1-MCP at $10^{\circ}C$ for 24 h. Ethylene production and respiration rate were strongly inhibited in 1-MCP-treated fruits at $20^{\circ}C$. It was also observed that there was less ethanol and acetaldehyde evaporation in 1-MCP-treated fruits stored at $20^{\circ}C$ compared to those in control fruits not treated with 1-MCP. Fruit qualities, such as firmness, titratable acidity (TA), skin color, and decay, changed more slowly in 1-MCP-treated fruits stored at $20^{\circ}C$ than in untreated fruits. There were no differences in the ethylene production or respiration rate between the groups of fruits stored at $0^{\circ}C$ throughout the experiment. Chilling injury was also inhibited by the application of 1-MCP during storage at $0^{\circ}C$. When the fruits stored at $0^{\circ}C$ with or without 1-MCP were transferred to $20^{\circ}C$ after 25 days, the differences in ethylene production and respiration rate, firmness, TA, TSS, and acetaldehyde and ethanol evaporation between the initial (after being stored at $0^{\circ}C$ for 25 days) and the final measurements (after being stored at $0^{\circ}C$ for 25 days and then transferred to $20^{\circ}C$ for three days) were lower in 1-MCP treated fruits than in non-treated fruits. The postharvest application of 1-MCP in Formosa plums showed positive effects at both $0^{\circ}C$ and $20^{\circ}C$ storage conditions with regard to quality, such as low ethylene production and low respiration rates, firmness, TA, ethanol, and acetaldehyde evaporation, chilling injury, and decay.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.21 no.2
• /
• pp.511-520
• /
• 2020

Owing to global warming, heat waves have become stronger in the summer, and research on improving the thermal environment of green spaces, such as urban parks, is being conducted. On the other hand, studies on improving the urban thermal environment, which is changing due to the greening pattern and the intensity of the wind, are still insufficient. This study analyzed the temperature of the green spaces on campus to understand the factors affecting the temperature changes. After investigating the covering condition and planting form of the site, factors, such as temperature, humidity, wind direction, wind speed, and illuminance, were measured. The most influential factors on the temperature distribution are evapotranspiration and wind - induced heat transfer. The other major factors affecting the temperature change were the type of cover, wind velocity/wind direction, type of planting, shade / solar irradiance. In the type of cover, the plant was classified as low temperature, and the asphalt pavement was classified as high temperature. In wind speed, instantaneous temperature was reduced by 1.2 ℃ in southern wind, 0.7 ℃ in the westerly wind, 0.4 ℃ in the north wind and 0.5 ℃ in the east wind when a wind of 3.5m/s or more was blown.

• Applied Biological Chemistry
• /
• v.39 no.1
• /
• pp.25-31
• /
• 1996

Transgenic tobacco plants expressing calmodulin derivative($lys{\rightarrow}ile$ 115 calmodulin) and hygromycin resistance genes or hygromycin resistance gene alone(control) were generated by Agrobacterium-mediated DNA transfer. Seeds obtained from the transgenic plants($F_o$) were tested for resistance to hygromycin and the expected 3 : 1 ratio was observed. The expression of calmodulin derivative in the tobacco plants was identified by a combined method of Western blot and Chemiluminescence. The effects of surface sterilizers on the germiation of seeds from transgenic tobacco plants were tested in Murashige and Skoog agar medium. Seeds obtained from transgenic tobacoo plants expressing the calmodulin derivative showed no fungi contamination with normal germination by treating with sterilized water alone or sodium hypochlorite(2% effective chlorine). In contrast, seeds from the control transgenic tobacco plants showed severe contamination with fungi by treating with sterilized water alone and showed no contamination with normal germination by treating with sodium hypochlorite(2% chlorine). The effects of calcium concentration on the germination of seeds from transgenic tobacco plants were tested in Murashige and Skoog agar medium. Seeds obtained from transgenic tobacco plants expressing the calmodulin derivative showed better germination frequency than that of the control transgenic tobacco seeds in the medium containing 30 mM $CaCl_2$. The data raise the possibility that the expression of calmodulin derivative gene in tobacco plants could increase adaptability of the seeds to environmental stresses.

• Journal of Korea Port Economic Association
• /
• v.29 no.4
• /
• pp.119-134
• /
• 2013

Korea has established the MOMAF (Ministry of Maritime Affairs and Fisheries) in 1996 while only a few countries have adopted the unified management system for the area of maritime, oceans and fisheries affairs. The Ministry has been broken up to three parts of maritime affairs, oceans and fisheries and allocated to each related ministries in 2008, and reorganized as the Ministry of Oceans and Fisheries including maritime affairs in 2013. However, the newly established MOF (Ministry of Oceans and Fisheries) has been evaluated as simply duplicated the former organization so as not to meet the oceanic environmental changes. This paper aims to suggest the appropriated organizational reinforcements measures on the basis of analysis of questionnaire survey which has been conducted targeting experts such as academic researchers and industry field players in the area of oceans, maritime and fisheries. The survey pointed out mainly five scopes such as (1) transferring the administrative task of shipbuilding and plant industries from the existing Ministry to the MOF, (2) reinforcing the structural functions of maritime, port construction and logistics affairs, (3) collaboration system with related Ministries for the ocean sovereignty, (4) securing the financial support system for the maritime industries, (5) transferring the management authority of maritime and ocean universities from the existing Ministry to the MOF. Looking back on the interministerial interest conflicts, it is very difficult to agree on the transfer of the existing task of above first and fifth suggestions. But the remain three suggestions could be done with interior abilities of the MOF by means of structural changes and professional manpower supplement.

• Proceedings of the Korean Radioactive Waste Society Conference
• /
• 2005.11a
• /
• pp.126-133
• /
• 2005

Securing of radioactive waste disposal site and the related operations for disposal of low and intermediate level radioactive waste is being actively carried out in Korea. For disposal of radioactive wastes, physicochemical and radiological status and integrity of radioactive wastes must be secured first. Also, waste generators must provide this information to disposers. In addition, to secure the safety of waste disposal, waste acceptance criteria (WAC) and site specific waste acceptance criteria (SWAC) to consider characteristics of the disposal site are required. Radioactive wastes must be processed, generated, managed and transferred in accordance with these criteria. [1] For this, evaluation of properties on each of the radioactive wastes must be performed. However, in reality, atomic power plants are experiencing difficulties in relation to this due to the large quantity of radioactive waste generation. In order to solve this problem, IAEA and major overseas countries have developed, thus are using waste certification program (WCP) and quality assurance program (QAP) [2,3]. On the basis of these programs, radioactive waste certification program has been developed for safe disposal of radioactive wastes in Korea to satisfy the provisions specified in 'low and intermediate level radioactive waste transfer guidelines' of announcement No. 2005-18 from the Ministry of Science and Technology and specific site waste acceptance criteria (tentative plan). In addition, it is being planned to administer amendment on commercial atomic power plant related procedures and ensile staff training in order for early introduction and operation of radioactive waste certification system.

• Journal of the Korean Institute of Traditional Landscape Architecture
• /
• v.33 no.1
• /
• pp.31-40
• /
• 2015

This study aims to comprehend that Seokpajeong garden for aspect of space change. Spatial characteristics according to the transfer of ownership are classified as period. And investigate the aspect of space change in Seokpajeong garden based on literature and painting, newspaper, photo. The results were as follows. First, Investigate the construction and change of Seokpajeong garden. Accordingly, spatial characteristics of Seokpajeong garden are classified into three period. 1st period is Kim-Heung Keun owned Samgyedong-jungsa garden. 2nd period is Daewongun hold Seokpajeong garden. 3rd period is damaged original form of Seokpajeong garden from Korean War to current time inclusive. Secondly, Kim-Heung Keun owned Samgyedong-jungsa garden has characteristics of water system centric space and many buildings. In addition accept foreign culture like chinese pavilion and Byeoldang Villa. and plant unique flower and leaf in garden. Thirdly, According to Seokpajeong garden folding screen, Daewongun owned Seokpajeong garden accept organization of space in Samgyedong garden. But different locations of Sarangchae in folding screen means possibility of move building to current position. So, additional historical research is required with representation of chinese pavilion location. Fourthly, Seokpajeong garden was damaged from original form to frequent changes of ownership. Transform of geographical features and water system as well as Anchae and Sarangchae, back side of a outbuilding are only the remained among many buildings. Also, Seokpajeong garden is more fell to the subsidiary facility of Seoul Museum than Wonrim. Therefore restoration and recovery of original form are urgent.