• Magazine of the Korean Society of Agricultural Engineers
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• v.43 no.2
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• pp.94-104
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• 2001

A pilot study was performed at the experimental field of Konkuk University in Seoul, to examine the feasibility of the constructed wetland system for sewage and the effect of treated sewage irrigation on the paddy rice culture and its soil characteristics. The constructed wetland performed well, in that effluent concentrations of pollutants were significantly lower than concentrations of the influent. Median removal efficiencies of BOD$_{5}$ was about 78% and slightly lower during winter. Removal efficiencies form TN and TP were approximately 48 and 21%, respectively, and relatively less effective than that of BOD$_{5}$. Irrigation of treated sewage to paddy rice culture did not affect adversely in both growth and yield of rice. Instead, plots of treated sewage irrigation showed up to 50% more yield in average than the control plot. It implies that treated sewage irrigation might be beneficial to rice culture rather than detrimental as long as it is treated adequately and used properly. Soil was sampled and analyzed before transplanting and after harvesting. pH was slightly increased due to irrigation water, but it may not be concerned as long as the treated sewage is within the normal range. EC was increased in first year but decreased in second year, therefore salts accumulation in the soil could be less concerned. OM and CES was slightly increased, which might be beneficial on growing plants. TN did not show apparent pattern. Available phosphorus was decreased after rice culture, but the quantity of phosphorus(TP-available phosphorus) was rather increased which implies that excessive phosphorus supply may result in phosphorus accumulation in the soil. Overall, the constructed wetland was thought to be an effective sewage treatment alternative, and treated sewage could be reused as a supplemental source of irrigation water for paddy rice culture without causing adverse effect as long as it is treated adequately and used properly. For full-scale application, further investigation should be followed on environmental risk assessment, tolerable water quality, and fraction of supplemental irrigation.ion.

• 한국항공운항학회:학술대회논문집
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• 2015.11a
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• pp.127-132
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• 2015

조직의 안전문화가 사고의 원인이 될 수 있다는 것이 알려지면서 안전문화의 개선과 정착의 중요성이 강조되고 있다. 우리나라는 항공법 제49조에 지정전문교육기관은 자체 안전관리시스템을 운영하도록 규정하고 있으며 관련 규정에는 조직의 안전문화를 조사하여 상태를 파악하고 발견된 문제점을 개선할 것을 권고하고 있다. 본 논문에서는 교통안전공단에서 개발한 축약형 CASS Scale을 사용하여 조종사양성 교육기관의 안전문화지수를 측정하였다. 측정결과 안전문화 평균치는 3.711로 나타났으며 하위지표의 측정결과는 직원 권한위임에 대한 평균값이 3.980으로 가장 높게 나타났고, 상벌체계에 대한 평균값이 3.309로 가장 낮게 나타났다. 서비스제공자는 이러한 측정 결과에 근거하여, 취약부분에 대한 개입전략을 수립, 적용함으로써 조직문화 향상에 도움을 줄 것으로 사료된다.

• Magazine of the Korean Society of Agricultural Engineers
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• v.44 no.7
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• pp.14-24
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• 2002

The effect of reclaimed water irrigation on paddy rice culture was evaluated by pilot study at the experimental field of Konkuk University in Seoul, Korea. The sewage was treated by constructed wetland system, and its effluent was used as irrigation water for four treatments and one control plots with three replications. Irrigation of reclaimed water onto paddy rice cultures did not adversely affect the growth and yield of rice. Instead, experimental rice plots of reclaimed water irrigation displayed about 10 to 50% more yield on average than controls. This implies that reclaimed water irrigation might be beneficial rather than harmful to rice culture as long as the sewage is treated adequately and used properly. The amount of irrigation water had little effect on experimental rice cultures, but its strength was important. The strength of treated sewage was not a limiting factor in this study, and no lodging was observed even with a relatively high nitrogen concentration (up to 160mg/L). In general the paddy soil was not affected by reclaimed water irrigation. However, there was an indication that continuous irrigation with high strength of reclaimed water might cause salt accumulation in the soil. Supplemental use of reclaimed water with existing sources of irrigation water is recommended rather than irrigation with a single source of reclaimed water. Overall, the results demonstrated that reclaimed water could be reused as a supplemental source of irrigation water for paddy rice culture without causing adverse effects as long as it is properly managed. For full-scale application, further investigation should be done on environmental risks, tolerable water quality, and fraction of supplemental irrigation.

• KSBB Journal
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• v.15 no.4
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• pp.342-345
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• 2000

A novel pre-purification method was developed for producing peroxidase to guarantee high purity and yield from plant cell cultures in large-scale process. This method was a simple and efficient procedure for the isolation and pre-purification of peroxidase from the biomass consisting of active clay treatment followed by cationic exchange chromatography. The use of active clay in the pre-purification process allows for rapid and efficient separation of peroxidase from interfering compounds and dramatically increases yield and purity of crude peroxidase for purification steps compared to alternative processes. This pre-purification process serves to minimize the buffer usage size and complexity of the HPLC operations for peroxidase purification. This process is readily scalable to a pilot plant and eventually to a production environment where mass production of material are expected to be produced.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.25 no.4
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• pp.1-23
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• 2017

Organizational culture among flight crews has a profound impact on the individual attitude and behavior of member flight crews, and active training is conducted focusing on improving flight crews' Crew Resource Management(CRM) performance. However, adequate research and training on the relationships between flight crew's individual culture and CRM performance have not been conducted. Hence, this study examined the effect of individual cultural values on CRM performance and the moderation effect of psychological safety, with captains and first officers working for commercial airlines as participants. For the factors related to individual cultural value scale, power distance had no significant effect on CRM performance, uncertainty avoidance had a significant negative effect, and individualism had a significant positive effect. With regard to the moderation effect of psychological safety on the relationships between individual cultural values and CRM performance, a significant interaction was found between power distance and CRM performance, but not between uncertainty avoidance and CRM performance, or between individualism and CRM performance. Power distance and CRM performance exhibited a strong negative correlation in case of low psychological safety. Compared to existing research measuring the cultural characteristics of pilot groups on a national or organizational culture level, this study is uniquely valuable in that it also covers the relationship between individual cultural values of commercial airline flight crews and CRM performance.

• Magazine of the Korean Society of Agricultural Engineers
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• v.45 no.4
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• pp.55-65
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• 2003

Pilot study was conducted to examine the effects of ponded-water depth and reclaimed wastewater irrigation on paddy rice culture. For the ponded-water depth effect, three treatments of shallow, traditional, and deep water depths were applied, and each treatment was triplicated. The irrigation water for the treatment pots was an effluent from constructed wetland system for sewage treatment, while the control pot was irrigated with tap water kept traditional ponded-water depth. Irrigation water quantity varied with ponded-water depth as expected and drainage water quantity also varied similarly, which implies that shallow irrigation might save irrigation water and also reduce environmental impacts on downstream water quality. Rice growth and production were not significantly affected by ponded-water depth within the experimental condition, instead there was an indication of increased production in shallow and deep ponded-water depths compared to the traditional practice. Raising drainage outlet to the adequate height in paddy dike might be beneficial to save water resources within the paddy field. There was no adverse effect observed in reclaimed wastewater irrigation on the rice production, and mean yield was even greater than the control pots with tap water irrigation although statistically not significant. Water-saving irrigation by shallow ponded-water depth, raising the outlet height in diked rice paddy fields, minimizing forced surface drainage by well-planned irrigation, and reclaimed wastewater irrigation are suggested to save water and protect water quality. However, deviation from traditional farming practices might affect rice growth in long term, and therefore, further investigations are recommended before full scale application.

• Journal of Microbiology and Biotechnology
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• v.17 no.10
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• pp.1638-1644
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• 2007

The effect of carbon sources on tacrolimus production by a mutant strain of Streptomyces clavuligerus CKD 1119, an isolate from soil, was examined. Among the carbohydrates and oils tested in this work, a mixed carbon source of soluble starch and com oil was the best. An analysis of the culture kinetics also showed that, in contrast to the carbohydrates, the com oil was consumed later in the antibiotic production phase, implying that the oil substrate was the principal carbon source for the biosynthesis of tacrolimus, and this was directly proven by experiments using $^{14}C$-glucose and $^{14}C$-oleate substrates. Furthermore, com oil induced the formation of lipase by the mutant strain, whereas the addition of glucose significantly repressed lipase activity. The lipase activity exhibited by the FK-506-overproducing mutants was also observed to be directly proportional to their tacrolimus yield, indicating that a high lipase activity is itself a crucial factor for tacrolimus production. A feasibility study with a 200-1 pilot-scale fermentor and the best strain (Tc-XII-15322) identified in this work revealed a high volumetric and specific productivity of about 495 mg/l and 0.34 mg/mg dry mycelium, respectively.

• Microbiology and Biotechnology Letters
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• v.22 no.2
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• pp.197-202
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• 1994

Microalga, Spirulina platensis has been cultivated in a pilot scale photo-bioreactor to treat wastewater and to produce high protein feedstocks from swine waste containing medium. 0.31(1/day) of specific growth rate and 0.170 of bioenergeric yield were obtanined from batch cultivation in 30% waster containing medium, compared to 0.71(1/day) and 0.545 from clean culture. An optimal dilution concentration was decided as 20% of working volume, based upon the cell growth and biomass productivity. The removal rate of nitrates in the wastewater was decreased as the adding concentration of wastewater was increased while the decrease of total phosphates was reversed, showing 0.33(1/day) and 0.30(1/day) of rate constants for nitrate removal in 10% addition and for phosphate removal in 30% addition, respectively. The chemical composition and amino acid profile of the biomass were superior to those of commerically available health food product, Spirulina sp.

• Journal of Microbiology and Biotechnology
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• v.32 no.5
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• pp.621-629
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• 2022

Bacterial outer membrane vesicles (OMVs) typically contain multiple immunogenic molecules that include antigenic proteins, making them good candidates for vaccine development. In animal models, vaccination with OMVs has been shown to confer protective immune responses against many bacterial diseases. It is possible to genetically introduce heterologous protein antigens to the bacterial host that can then be produced and relocated to reside within the OMVs by means of the host secretion mechanisms. Accordingly, in this study we sought to develop a novel platform for recombinant OMV (rOMV) production in the widely used bacterial expression host species, Escherichia coli. Three different lipoprotein signal peptides including their Lol signals and tether sequences-from Neisseria meningitidis fHbp, Leptospira interrogans LipL32, and Campylobactor jejuni JlpA-were combined upstream to the GFPmut2 model protein, resulting in three recombinant plasmids. Pilot expression studies showed that the fusion between fHbp and GFPmut2 was the only promising construct; therefore, we used this construct for large-scale expression. After inducing recombinant protein expression, the nanovesicles were harvested from cell-free culture media by ultrafiltration and ultracentrifugation. Transmission electron microscopy demonstrated that the obtained rOMVs were closed, circular single-membrane particles, 20-200 nm in size. Western blotting confirmed the presence of GFPmut2 in the isolated vesicles. Collectively, although this is a non-optimized, proof-of-concept study, it demonstrates the feasibility of this platform in directing target proteins into the vesicles for OMV-based vaccine development.

• Korean Journal of Social Welfare
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• v.66 no.3
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• pp.55-73
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• 2014

The purpose of this study was to develop and validate Korean version of Deaf Acculturation Scales(DAS). Pilot items were made a faithful translation of the Acculturation Scales of Maxwell-McCaw and Zea (2011) and were modified for Korean Deaf people. The Scale involves two dimensions, in order to measure the acculturation of Deaf people; Deaf acculturation and hearing acculturation. Using factor analysis, we developed a Korean version of DAS consisted of twenty-five items for Deaf acculturation dimension and twenty-five items for hearing acculturation dimension. These analysis supported the four factors of Deaf acculturation dimension and the five factors of hearing acculturation dimension. Reliability, assessed by Cronbach's ${\alpha}$, was .93 for Deaf acculturation and .93 for hearing acculturation, respectively, which confirm the Koran version of DAS. Construct validity was demonstrated through correlation with Deaf acculturation-related variables: age, age of Deafness, Degree of hearing loss, American Sign Language ability, and lip-reading ability. Criterion validity was supported by correlation with Collective Self-Esteem Scale. Limitation and implication of this study and direction for future research were discussed.