• KSBB Journal
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• v.8 no.5
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• pp.478-482
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• 1993

Perfusion culture was conducted in Celligen perfusion culture system using a self-constructed hybridoma cell and low serum medium. The culture system employed hollow fiber to separate cells from the culture broth. Maximum cell density of $2.1\times10^7$ ce11s/m1, 10 times higher than in batch culture, could be achieved. Concentration of monoclonal antibody (MAb) was 4 times higher and production rate at maximum feed rate was 9 times higher than in batch culture. Glucose concentration was very important for the cell growth and MAb production. When glucose concentration was below 1g/l, i. e. 0.5~0.9g/l, specific MAb production rate decreased but cell concentration still increased. As the glucose concentration goes above 1g/l, specific MAb production rate increased and remained at maximum value at more than 1.5g glucose/l. The maximum value of the specific Mab production rate was similar to that of batch culture.

• Journal of Korean language education
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• v.28 no.3
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• pp.127-152
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• 2017

The purpose of this study is to clarify the perception and educational needs of international college students regarding the culture of college life. A questionnaire was given to international college students who are studying at universities in Korea. The results showed that international college students need to study about the culture of college life and had a perception that it is desirable to learn this through general education classes or freshman subjects after entering university. Also, the culture of college life can be divided into nine categories: bachelor's system; career and employment; university support centers and systems; interpersonal relations; departmental events; housing and living expenses; freshmen's events; exchange activities and programs; and cultural experience activities. International college students showed higher learning needs in order of career and employment; cultural experience activity; and bachelor's system. In addition, the characteristics of the learners showed different educational needs according to year of study and Korean language proficiency. The significance of this study is to specify the items of the culture of college life required for international college students, to measure the validity and reliability of these items, and to categorize the elements of the culture of college life.

• International Journal of Computer Science & Network Security
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• v.21 no.11
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• pp.368-372
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• 2021

The article identifies the features of the digital culture of modern society in the dynamics of its impact on the education sector, identifies the main directions of digitalization education, an objective analysis is presented, the possibilities of examination as a scientific assessment are determined "Digital reforms" of education, the role of traditional values of educational culture in expertise and improvement digital innovations in the education system, identified the main contradictions in the development of digital culture, to determine the directions of its improvement. The article describes the three main components of information technology as a complex of hardware, software and a system of organizational and methodological support; the description of analog and digital information technologies is presented. The authors list the most common multifunctional office applications and IT tools; the advantages of using IT in the educational process are highlighted.

• Journal of the Korean association of regional geographers
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• v.12 no.1
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• pp.16-30
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• 2006

In terms of world system theory, the historical period of Yanbian area was divided into 3 parts: Japan colonial period which was assigned to the periphery of world system, socialist period which escaped from the world system, and the reform-open period that was reincorporated to world system. The cultural character of each period was studied. The conclusions are as follow. During the period of periphery of world system, Yanbian area as an area where the massed Korean people lived, was dominated by Korean peninsular culture. However, Yanbian area was also affected by the Japanese and Chinese cultural assimilation policy. During the period that Yanbian area aparted from the world system, it was affected by the requirement of unique socialist culture assimilation, and traditional cultures were hard to keep. During the period of reincorporation to the world system with lighten of minority policy by Chinese government, traditional national culture begin revived, but due to extend intercourse of Yanbian with China mainland and Republic of Korea, China-Korean culture of Yanbian area was strongly affected by Chinese and Korean culture too.

• Proceedings of the KSME Conference
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• 2008.11a
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• pp.1411-1414
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• 2008

It is reported that mechanical stimulation takes a role in improving cell growth in skeletal system. And various research groups have showed that developed bioreactor to stimulate cell-seeded and threedimensional scaffold. In this study, we designed a custom-made bioreactor capable of applying controlled compression to cell-seeded agarose gel. This device consisted of a circulation system and compression system. In circular system, culture chamber was sealed for prohibiting contamination and media solution was circulated by pump. In compression system, mechanical stimuli were controlled by LabVIEW software and mechanical transfer system. Cell-encapsulated agarose gels were cultured for up to 7 days. There were significant differences between the number of cells grown in dynamic cell culture and in static cell culture from 3 days to 7 days.

• YAKHAK HOEJI
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• v.45 no.3
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• pp.245-250
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• 2001

Aminoacyl tRNA synthetases of bacteria are known as potential targets for new anti-microbial agents. To isolate new inhibitors of bacterial methionyl-tRNA synthetases from natural sources, a new target-oriented screening system using whole cells which are over-expressing a target enzyme was developed. Approximately 8,000 culture broths of microorganisms from soils were tested by this screening system. Among them, ten culture broths was found to contain inhibitory activity against methionyl -tRNA synthetases of Escherichia coli. For the validation of the screening system, this new method was compared with in vitro enzymatic method. Seven out of 10 culture broths showed inhibitory activity against methionyl-tRNA synthetases of E. coli. This result showed that the new screening system was comparable to the enzyme assay. Thus we believe that our screening system as a new method can be applied for the screening of new antibiotics inhibiting bacterial methionyl-tRNA synthetases from natural products.

• The Journal of the Korea Contents Association
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• v.8 no.12
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• pp.301-309
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• 2008

This paper explores whether there is significant difference or not in the empowerment of social workers, e.g. individual's business-oriented, business relationship, and compensation system, according to the organizational culture types of social welfare facilities such as community culture, development culture, hierarchical culture, and reasonableness culture. By means of survey, this research targeted the social workers of social welfare facilities. The culture types that social workers recognize are sorted into community culture, development culture, hierarchy culture, and reasonableness culture according to the division of Kimberly and Quinn (1984). This study shows that there is significant difference in individual’s business-oriented, business relationship, and compensation system according to the type of organization culture.

• Fisheries and Aquatic Sciences
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• v.7 no.2
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• pp.76-83
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• 2004

To supply fresh and quality quarantined seafood in live seafood specialty restaurants, facilities for short-term culture or holding of live marine fish and shellfish are a necessity. In this study, the performance of a simple recirculating aquarium system for the culture and holding of marine fish was evaluated. The aquarium system consisted of a culture tank, a foam fractionator for solids removal, and a Styrofoam bead filter for nitrification and solids trapping. In the first trial, the aquarium was stocked with a total of 12 kg Korean rockfish, which were fed approximately $0.5\%$ of the total fish body weight daily. During the 2-month culture period, total ammonia nitrogen (TAN) and nitrite nitrogen $(NO_2-N)$ concentrations remained below 1mg/L and 2mg/L, respectively. The chemical oxygen demand (COD) fluctuated between 13.6 and 31.2 mg/L on selected sampling days. The total suspended solids (TSS) removed by the foam fractionator was between 2.7 and 4.6g daily. The Styrofoam bead filter not only reduced TAN and $NO_2-N$ in the culture tank water, but also trapped solids equivalent to 8.3-26.7\% of the weight of feed supplied. In Trial 2, 30kg of live fish were held in the aquarium without feeding for a 24-hour period and the water quality parameters were monitored. TAN and $NO_2-N$ concentrations first increased and then decreased to around 0.3mg/L. These results demonstrate that the recirculating aquarium system is a functional option for the short-term culture or holding of marine fish.

• Korean System Dynamics Review
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• v.16 no.3
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• pp.5-29
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• 2015

The importance of the concept of safety culture has increased in the security of high-risk facility after Chernobyl accident in 1986. This paper elaborated the concept of safety culture and its main factors by Causal Loop Diagram. Due to the decline of safety culture, the occurrence of incidents and accidents require more and more corrective actions to the members of high-risk facilities and thereby increasing their workloads. Employees who must complete the task within the given time have to have time pressures and don't comply with the rules and procedures. Also, a schedule pressure is a big stress for employees, causing mistakes in precision work. In order to improve these problems, CLD of the safety culture in this paper suggests hiring more workers, re-allocation of given workloads and strengthen the learning, communication capabilities and safety leadership. In addition, the two real accident cases were analyzed to test the feasibility of the System Dynamic simulation model through the process of structuring the fault trees on the stationary black out accident in Kori unit 1 in South Korea and Kleen Energy power station explosion in US. The simulation results show that the various safety factors cause the serious accident combined with mechanical failure and safety culture will reduce the possibility of the accidents in these high-risk organizations. This simulation model can contribute to analyzing the impact of the organizational and human factors of safety culture and can provide the alternatives in high-risk facilities.

• Journal of Advanced Navigation Technology
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• v.27 no.4
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• pp.346-350
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• 2023

The International Civil Aviation Organization (ICAO) introduced a safety management system in the aviation sector for aviation safety and mandated the implementation of safety management systems and national safety programs. The activation of the airline's safety management system is not just a requirement for organizational members to create and comply with necessary regulations, but a safety culture to promote and improve flight safety must be established within the organization. Therefore, the safety culture of airlines acts as a major key variable in the safety management system that directly affects safety performance. This study compared the data from the European pilot safety culture awareness, which was the basic data of the survey, with statistics on the safety culture awareness of domestic flight attendants to analyze the differences in safety culture between the two groups.