• The Korean Journal of Food And Nutrition
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• v.31 no.2
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• pp.272-277
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• 2018

This research was conducted to elucidate the optimum conditions for the antibacterial activity of konjak jelly using the evolutionary operation-factorial design technique. In the first set of experiments, concentration of a coagulation agent, soaking liquid, and temperature of water were set to 0.4%, $0.6{\times}10^{-2}N$, and $65^{\circ}C$ as a central point, respectively. The highest antibacterial activity was acquired at E21, in which the number of bacteria was 1.25 log cfu/g. Because the code of changes in the main effect was (-), it could be decided that the central point of the first set was not the optimum point. Although antibacterial activity in the second set was improved, the values of the main effect were higher than that of changes in the mean effect. The central point of third set was concentration of coagulation agent 0.8%, concentration of soaking liquid $1.0{\times}10^{-2}N$, and temperature of water $65^{\circ}C$. It was found that the antibacterial activity of central point in the third set was highest among all the tested set. Further, all the necessary conditions were appropriate to reach the optimum condition. The antibacterial activity of the central point in third set was more than 1,000 times higher than that of E11, in first set.

• Journal of the Korean Society of Propulsion Engineers
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• v.24 no.5
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• pp.34-42
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• 2020

In modern air combat, infrared signals play an important role in the detection of opponents and must be reduced to improve survivability and stealth. In particular, IR signals generated in the wake of aircraft engines have high intensity and short wavelengths, so most heat-tracking missiles detect these signals. Accordingly, the measurement and characteristic analysis of Gas radiation signals from the engine's wake were carried out in this study. Micro turbojet engine has been configured to simulate a real aircraft turbofan engine, and the characteristics of IR signal reduction by adjusting the bypass ratio were identified. Through this, the IR signal characteristics for each wavelength are analyzed and verification of signal reduction technologies is performed.

• International Commerce and Information Review
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• v.10 no.4
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• pp.221-250
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• 2008

This study investigated and analyzed the export competitiveness of Gyeonggi-Do and the effect of Korea-US FTA on its export competitiveness. By reviewing the current status of trade structure and implementing trade specialization index(TSI) of export commodities of Gyeonggi-Do, the investigation has listed the specific export commodities with competitiveness for increasing the volume of its export in the United States, in the short, mid and long run perspectives. From the findings in this study, it suggests specific trade and commercial policies to Korea-US FTA including implementing commodity-oriented export supporting system, strategic marketing method, economic-free-zone plan, R&D investment, export financing and regional economic cooperation.

• KSTLE International Journal
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• v.1 no.1
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• pp.43-47
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• 2000

Oil seals will experience a small amplitude dynamic excitation due to the shaft eccentricity as well as out-of-roundness of the shaft. The direct integration method is selected to analyze the time domain response of the seal lip-shaft contact. The physical properties of rubber seal materials are experimentally analyzed. Effects of both frequency and temperature on the material stiffness behavior are investigated for the linear viscoelastic materials of the seal. Using the nonlinear transient model, a finite element analysis of the lip-shaft contact behaviors under dynamic conditions is presented as a function of the shaft eccentricity, the shaft interference and the garter spring stiffness. The FEM results based on the experimental data indicate that the increased rotating speed may produce the separation conditions. These results will be very useful in predicting the leakage of oil seals under dynamic conditions.

• Asian Journal of Turfgrass Science
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• v.8 no.3
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• pp.179-192
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• 1994

Much attention has been paid recently to environmental destruction by golf course constructions in Koera. An efficiency and up-to-date technology on the planning and design practices has been requested to minimize the environmental impacts. Computerized systems for golf course design in the point of physical conservation of environment were discussed here. Geograpic Information System were applied on the process of geograpical data input and analysis through the final outputs, Simulation works by the total database management make enable to pre-investigate of the design in view of an assessment of environment impacts. It is also possible to evaluate plans easily and propose the alternatives properly. Precise quantity caculation of en-gineering works by computer system should be guarantee scientific, economic, and environme-ntally sound golf course design.

• Animal Systematics, Evolution and Diversity
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• v.8 no.2
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• pp.301-324
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• 1992

A large number of Demospongiate have been collected from 18 localities in Cheju Island and its adjacent waters during the period from 1970 to 1991. The identified Demospongiae consist of 67 species, 40 genera and 30 families. Among them 11 species were new to Koera; Oxeostilon fernaldi, Microciona gradalis, Tedania ignis, Haliclona koremella, Adocia neens, Callyspongia variabilis, Suberites axinelloides, Anthosigmella raromicrosclera, Epipolasis kushimotoensis, Acanthella insignia, and Spongosorites salimonensis.

• Animal Systematics, Evolution and Diversity
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• v.38 no.1
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• pp.1-13
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• 2022

Three Pleuromamma copepods were newly collected from the South Sea of Korea in the summer when the Tsushima Warm Current was strong. They were identified as Pleuromamma abdominalis(Lubbock, 1856), P. indica Wolfenden, 1905, and P. xiphias (Giesbrecht, 1889). Although these species have been reported in world oceans, they were first reported from Korean waters. So far, four species of Pleuromamma (P. borealis Dahl, 1893, P. gracilis Claus, 1863, P. piseki Farran, 1929, and P. robusta (Dahl, 1893)) have been recorded in Korean waters. We provided re-description of these three species insufficiently described by previous authors and key characters for species identification in addition to species hitherto known in Korea.

• Proceedings of the KSPS conference
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• 2000.07a
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• pp.165-165
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• 2000

In the phoneme level, English stop sounds are classified with the feature of 'voicing': voiceless and voiced (p/b, t/d, k/g). But when realized, a voiceless stop is not alwats the same sound. For example, the two 'p' sounds in 'people' are different. The former is pronounced with much aspiration, while the latter without it. This allophonic differnece between [$P^h$] and [p] out of an English phoneme /p/ can be well explained to Koreans because in Korean these two sounds exist as two different phonemes {/ㅍ/ and /ㅃ/ respectively). But difficulties lie in teaching the English voiced stop sounds (/b, d, g/) to Koreans because in Korean voiced stops do not exist as phonemes but as allophones of lenis sounds (/ㅂ, ㄷ, ㄱ/). For example, the narrow transcription of '바보' (a fool) is [baboo]. In the word initial position, Korean lenis stops are pronounced voiceless and even with a slight aspiration while in the inrervocalic environments they become voiced, That is in Korean voiced stops do not occur independently and neither they have their own letters. To explain all these more effectively to Koreans, it is very helpful to use Korean Phenetic Alphabet (KPA) which is devised by Dr. LEE Hyunbok (a professor of phonetics at Seoul National Univ. and chairman of Phonetic Society of Koera.)(omitted)

• Journal of Korean Society for Atmospheric Environment
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• v.18 no.E3
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• pp.129-142
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• 2002

This paper provides a long-term perspective for ozone concentrations at 20 national air quality monitoring sites in Seoul from 1989 to 1998, which were managed by the Korean Ministry of Environment. Ozone episodes occurred more frequently in the east areas (Bangi, Guui, Seongsu, and Ssangmun) than in the west area (Guro and Oryu). When an ozone episode happened, hourly ozone concentrations over 80 ppb continued for an average of 4.0 hours at all sites. Annual variations in daily mean and maximum oBone concentrations showed broadly consistent upward trends at Ssangmun and Gwanaksan. Monthly mean ozone concentrations were the highest from May to June and the 99$^{th}$ and 95$^{th}$ percentile levels appeared higher during June, July, and August. The diurnal patterns of hourly mean ozone levels in urban areas showed typical photochemical formation and destruction, while the flat diurnal shape before 1996 at Gwanaksan indicated few significant photochemical reactions due to a lack of precursors of ozone. The occurrence of ozone over 80 ppb was ascribed to meteorological conditions such as high temperature, strong solar radiation, low relative humidity, and low wind speed with winds most frequently in a westerly direction.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.40 no.3
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• pp.478-490
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• 2015

Abundant data has been generated over the internet as the arrival of information age. To share the information, Wired, wireless network are required to transmit the data. Especially, In the wireless network which is using mobile device based on battery, energy consumption is growing due to uploading, downloading the abundant data on mobile device. In order to solve the problem, This paper addresses the protocol of the modified TCP congestion control that is being used for the most network protocol to save energy.