• Journal of Environmental Science International
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• v.12 no.10
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• pp.1079-1084
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• 2003

This study was carried out to check changes of components in the slaughter waste by the bacteria isolated from slaughter wastes from Gyungnam Province from May to June 2000, and to find usefu] organism for treatment of the waste. Bacteria used in this study were Aeromonas hydrophila, as the dominant of the waste. Optimum conditions for bacterial culture were obtained as the temperature of 35$^{\circ}C$, pH 6.5, and shaking of 120 rpm in nutrient broth. The mean values of dissolved oxygen was 4.14 mg/1; biochemical oxygen demand, 1731.21 mg/1; ratio of BOD/COD, 0.53-0.64; ratio of T-P/T-N, 1.0-1.41; and viable counts of the waste, 5.47${\times}$10$\^$7/ CFU. Little change in total nitrogen observed by 36 hr of the culture. The largest amount of increasing NH$_4$$\^$+/-N was observed in the sample that 10% of the waste added in nutrient broth with A. hydrophila showing the value of 29.19 mg/l at the beginning to 570.36 mg/1 by 36 hr of culture. However, the highest increasing ratio between initial amount and finals at 36 hr of culture showed as 41.6 times when 3% of the waste added. NO$_3$ -N was decreased showing the value of 71.27 mg/1 to 32.14 mg/1 by 24 hr of culture with the organism when 10% of the waste added in nutrient broth. Total phosphorus was decreased showing the value from 188.74 mg/1 to 101.41 mg/1 after 12 hr of culture with the organism when 5% of the waste added in nutrient broth, while T-P was decreased gradually by 24 hr of culture from 193.8 to 101.4 mg/1 when 10% of the waste added.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2017.05a
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• pp.560-562
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• 2017

This paper presents the development and test results of a test rig for confirming the hover performance of the coaxial propeller which is applied to the drone in order to carry out the mission that requires high payload such as the development of the courier drones. the performance of each propeller was measured by varying the thrust and torque according to the H/D ratio. the Thrust sensor and torque sensor were used to measure the thrust and torque generated when the propeller rotated, and a photo sensor was used to measure the rpm. it used the data acquisition system to acquire data from each sensor, and used the Labview softwaer to control data storage, monitoring and BLDC motor control. In the test, each propeller meansured the figure of mefit according to the chansge of the interval at the same rpm.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.21 no.3
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• pp.301-306
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• 2010

In this paper, a SIT(Source Independent Tree) method for ray tracing is proposed to enhance the efficiency of tree construction with reuse of sub tree in urban environment, As the SIT method is applied, the decrease of the number of nodes for picocell and microcell simulations is 100 times. And 88~98 % of the total nodes are reused with change of location of signal source from an analysis of node reuse efficiency. Therefore the proposed SIT method is useful in performance enhancement of ray tracing, especially, for multiple antenna simulation like as MIMO system and cell planning.

• Korean Journal of Microbiology
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• v.23 no.4
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• pp.259-264
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• 1985

The research was carried out for the purpose of finding effects of gerbal saponins on aflatoxin synthesis by Aspergillus parasitics NRRL 2999. A. parasiticus with $10^6$ conidia were grown at $30^{\circ}C$ for 9 days on the enriched medium that is optimum for the frowth and aflatoxins production by the mold. The inhibitory effect on the growth and aflatoxins produced by the mold occurred in the presence of 0.36% of crude red-ginseng saponin showing both the growth and aflatoxins production come to 62.3% (growth), 38.7% (aflatoxin $B_1$) and 22.9% (aflatoxin $G_1$) of the control. Thd next effective saponin to inhibit the growth and aflatoxins production was from burdock seeds. However, saponin extracted from honeysuckle flowers had no inhibitory effect. The mold caused no changes in the pH of the medium when it contained red-ginseng saponin. Red-ginseng saponin was more effective than the white-ginseng in inhibiting both the growth and aflatoxin production.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2019.10a
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• pp.97-97
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• 2019

사삼(沙蔘, Adenophorae Radix)은 "대한민국약전외한약(생약)규격집(KHP)"에 잔대 Adenophora triphylla var. japonica Hara 또는 사삼(당잔대, A. stricta Miq.)의 뿌리로 수재되어 있으나, 형태학적으로 유사한 제니(모시대, A. remotiflorus Miquel), 층층잔대(윤엽사삼, A. tetraphylla (Thunb.) Fisch), 더덕 Codonopsis lanceolata (Sieb. et Zucc.)과 오 혼용 우려가 있어 이들을 구별하기 위한 종 감별법이 필요하다. 본 연구에서는 '사삼'과 오 혼용 우려가 있는 종들을 구별할 수 있는 유전자 마커 개발을 위하여 DNA 바코드로 활용되고 있는 유전자 부위를 분석하여 ITS (25%), atpB-rbcL (15%), atpF-atpH (14%), rpl16 (13%), trnL-F (10%), matK (9%), rpoC1 (7%)에서 변이율(percent of variable sites)을 확인하였다. 또한, 분석한 유전자 부위 중 종간 차이를 확인하기 용이한 matK 구간을 활용해 기원종인 잔대, 당잔대와 형태적으로 유사하여 오 혼용될 우려가 있는 층층잔대, 모시대 및 더덕을 감별 할 수 있는 유전자 마커를 개발하였다. 본 연구를 통해 얻어진 염기서열과 분자 마커는 '사삼'의 품질관리에 유용하게 활용 가능할 것으로 사료된다.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2019.10a
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• pp.98-98
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• 2019

제니(薺苨, Adenophorae Remotiflori Radix)는 "대한민국약전외한약(생약)규격집(KHP)"에 모시대(Adenophora remotiflorus Miquel)의 뿌리로 수재되어있으나, 형태학적으로 유사한 잔대(A. triphylla), 당잔대(A. stricta) 및 더덕(Codonopsis lanceolata)과 오 혼용 우려가 있어 이들을 구별하기 위한 정확하고 객관적인 종 감별법이 필요하다. 본 연구에서는 '제니'의 기원인 모시대와 오 혼용 우려가 있는 종들을 구별 할 수 있는 유전자 마커를 개발하기 위하여 Genbank에 등록된 ycf2 구간을 활요하여 모시대와 잔대, 당잔대를 구분 할 수 있는 INDEL (insertion/deletion) 마커를 개발하였다. 또한, 보다 정확한 종감별을 위해 DNA 바코드로 활용되고 있는 유전자 부위의 염기서열을 분석하여 ITS (25%), atpB-rbcL (15%), atpF-atpH (14%), rpl16 (13%), trnL-F (10%), matK (9%), rpoC1 (7%)에서 변이율(percent of variable sites)을 확인하였다. 향후, 본 연구에서 개발된 INDEL 마커와 더불어 추가적으로 개발을 진행 중인 분자 마커는 한약재 '제니'의 품질관리에 활용 가능할 것으로 사료된다.

• Solar Energy
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• v.11 no.1
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• pp.61-68
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• 1991

Steady laminar natural convection heat transfer from the isothermal square beam attached to an adiabatic plate has been studied for various inclination angles of the adiabatic plate and Rayleigh number by using Mach-Zehnder interferometer in air. As the inclination angles change, the different temperature and fluid flow field were obtained by the ascending heated fluid and the adiabatic plate. In this study, the inclination angles were $0^{\circ}$(positive & negative), $45^{\circ}$(positive & negative), and $90^{\circ}$. The maximum total mean Nusselt number value was found at a positive inclination angle ${\theta}=45^{\circ}$.

• Journal of Korean Society for Quality Management
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• v.49 no.2
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• pp.127-143
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• 2021

Purpose: Smart Safety Living Lab is a Living Lab facility, constructed and operated by KITECH in Korea, to support the user experience(UX) evaluation, planning and certification of smart safety products and services. The purpose of this study is to develop a UX evaluation methodology that accommodates the characteristics of the Living Lab and smart safety products and services for a systematic and efficient UX evaluation in the Smart Safety Living Lab. Methods: A generic model of UX evaluation was first derived based on a review of related literature. Then, the generic model is revised to accommodate the characteristics of the Smart Safety Living Lab and smart safety products and services, resulting in the UX Evaluation Methodology for Smart Safety Living Lab (SSLL-UXEM). Results: The developed SSLL-UXEM consists of a structured process for UX evaluation, a guideline for conducting each step of the process, and a set of forms for recording the major evaluation results in each step. Conclusion: SSLL-UXEM can help to enhance the efficiency of the UX evaluation process and the consistency of the UX evaluation results. SSLL-UXEM is also expected to serve as a basis for UX evaluation in various living lab environments in the future.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.49 no.4
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• pp.273-279
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• 2021

Winglets are specialized wingtip devices to reduce induced drag, and they have been installed on Boeing-made aircraft since the 1980s, Airbus has also developed a winglet named 'Sharklet' since 2009 and has started providing them as an option to the A320 Family. The winglet has the effect of improving take-off performance, reducing fuel consumption, increasing payload, and increasing flight distance by reducing the induced drag generated at the tip of the wing. The purpose of this study is to analyze the actual flight data of the sharklet-installed and non-sharklet-installed models of the A321 aircraft to verify the fuel efficiency improvement due to the winglet installation, and to analyze the economic analysis accordingly. Through this, it can be used to determine the winglet installation when introducing an aircraft or to make a decision for upgrading the existing aircraft. To this end, a case study on the aerodynamic characteristics and effects of the winglet installation was conducted, and the economic analysis was verified.

• Asia-Pacific Journal of Business
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• v.12 no.4
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• pp.107-134
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• 2021

Purpose - Korean firms have entered the Mongolia, the world's top 10 resource rich country with huge market potential, since the diplomatic relations between Korea and Mongolia were established in 1990, but little is known about Korean firms' entry strategy in the Mongolian market. With this background, this study aims to investigate the seven cases of Korean firms doing business in Mongolia (SK Telecom, Samsung S1, T-Money, E1 Energy, Cafe Bene, E-Mart, and CU). Methodology - this study is based on numerous primary and secondary data about the Mongolian market, as well as Korean firms in Mongolia. Findings - the following three implications were derived from our case analysis: first, when entering into Mongolia, a thorough analysis of political and social risks and a good understanding of institutional voids should be preceded. Second, for this reason, entering through cooperation with local partners, such as joint ventures or franchising, is expected to increase the possibility of success. Third, unlike in the early days of Korean firms in Mongolia, the business environment in Mongolia has become more stable and predictable, and a friendly atmosphere for Koreans and Korean firms is forming, increasing the possibility of success and settlement of Korean firms. Research implications - this study contributes to extant literature by providing more systematic research on Korean firms in Mongolia and by presenting practical implications through the analysis of success and failure cases of Korean firms in the Mongolian market.