• Applied Microscopy
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• v.37 no.4
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• pp.231-238
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• 2007

Although the biological significance of the antennal sensillae to millipedes are widely understood, the structure and function of the antennal sensillae are still not clear and more precise analysis is required. Thus, this study initiate to reveal the fine structural characteristics of various sensory receptors on the antennae of millipede Oxidus gracilis were observed with field emission scanning electron microscopy(FESEM). The antennae generally include eight segments, called articles. On the surface of the antennae, there are a variety of sensory receptors which include olfactory and mechanical receptors. We could identify four different types of antennal sensillae in O. gracilis as follows: apical cone sensilla, trichoid sensilla, chatiform sensilla and basiconic sensilla. The most prominent is four large spital cone sensillae on distal tip of the 8th article. Both of trichoid and chaetiform sensillae are abundantly observed at the most of antennal articles. These sharply pointed structures are inclined and slightly curved toward the apex of the sensilla. The basiconic sensilla are further divided into three subtypes: large basiconic sensilla($Bs_1$), small basiconic sensilla($Bs_2$) and spiniform sensilla($Bs_3$). The $Bs_1$ is located at the 5th and 6th articles, while the $Bs_2\;and\;Bs_3 can be seen at the 5th and 7th articles, respectively.

• The Korean Journal of Quaternary Research
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• v.25 no.1
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• pp.1-13
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• 2011

To reinterpret the meaning of fluvial terraces in the Quaternary researches, the concepts and geomorphic properties of fluvial terraces are reviewed. Fluvial terraces are the alluvial landform that was once river channel or floodplain by paleochannel flowed in elevated areas from the current river by active incision of rivers due to the climatic changes and/or uplifts. As fluvial terraces are the remnants of alluviums after incisions of rivers, the major factors influencing on the incisions are the falling of erosion base, increase of river discharge and distinct geomorphic phenomenon of river. While it is generally known that fluvial terraces deposits in the upper or middle reaches of large rivers were formed during glacial periods, the deposits may be formed at the various periods due to the diverse natural environments and geomorphic properties of specific rivers, because there have been numerous cases that the ages of fluvial terraces in the upper or middle reaches of large rivers in Korea and China can be correlated to the interglacial periods.

• Journal of The Geomorphological Association of Korea
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• v.17 no.3
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• pp.1-16
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• 2010

Phytoliths, silica microfossil that produced within and between cells and tissues of plants are especially yielded in Gramineae with many different forms and can attribute to the reconstruction of climatic and environmental changes and agriculture activity of the Quaternary. The phytoliths in soil can remain for long periods of time, because of strong resistance to physical and chemical weathering. The spatial range of study is too small due to deposition of phytoliths directly to the soil. There are difficulties of phytoliths identification because of multiplicity and redundancy, so far uniform and exact classification scheme has not been adopted. Therefore we attempted phytolith classification system applied to Korea. The paleoenvironmental reconstruction research using phytholith are applicated in many parts of studies. Also high-resolution paleoclimatic reconstruction expected to be possible using phytolith indices of Iph and Ic as well as climatic indicator of phytolith morphology.

• Journal of the Korean Society of Propulsion Engineers
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• v.12 no.4
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• pp.24-32
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• 2008

We made a new propellant formulation to improve the productivity of Base Bleed Unit(aka BBU) by reducing of the curing time. We made an experiment with new propellant formulation such as binder characteristics and manufacturing process. In addition, we already tested several basic characteristics and the final performance of the new propellant. According to the test report, it was not only satisfied with all requirements in the specification, but it also contributed to improve productivity and reduced 53% of the curing time.

• The Bulletin of The Korean Astronomical Society
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• v.43 no.2
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• pp.43.5-44
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• 2018

한국천문연구원은 미국 텍사스대학교(UT)와 협력하여 2009년부터 2013년까지 IGRINS 분광기를 개발하였다. IGRINS는 UT의 맥도널드(McDonald) 천문대 2.7미터 망원경과 로웰(Lowell) 천문대의 4.3미터 망원경, 제미니(Gemini) 천문대 8.1미터 망원경에 장착하여 성공적으로 사용되어 왔으며, 최근 한국천문연구원이 제미니 천문대 운영에 정식으로 참여하면서 IGRINS와 유사한 관측기기를 8.1미터 망원경 전용으로 개발해 달라는 요청을 받고 개발계획을 준비하고 있다. 담금격자(immsersion grating)를 사용하는 IGRINS는 거대마젤란망원경(GMT)의 1세대 관측기기 중 하나로 선정된 적외선 고분산 분광기 GMTNIRS의 핵심 요소기술을 검증하기 위한 선행개발 기기의 의미도 갖고 있다. 한국천문연구원은 2011년 UT와 공동으로 GMTNIRS의 개념설계를 수행하였으며, 이후 개발팀에 카네기(Carnegie) 천문대가 합류하여 6.5미터 마젤란(Magellan) 망원경용으로 GMTNIRS와 유사한 담금격자 적외선 분광기를 개발하고 시험운영함으로써 GMTNIRS의 개발을 앞당기는 계획을 추진 중이다.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.22 no.12
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• pp.157-163
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• 2008

In the multi-phase interleaved converter with peak current mode control, current imbalance is measured when inductors of converter module are not exactly identical. In this paper current-sharing controller is proposed to balance phase current of converter modules. It also is designed to have good transient response. Proposed method implemented the 2-phase and 4-phase interleaved boost converter with imbalanced inductance. Experimental results verify the performance of Current share during the transient state of converter.

• Animal Systematics, Evolution and Diversity
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• v.18 no.2
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• pp.191-201
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• 2002

The first zoeal stage of Heptacarpus rectirostris (Stimpson, 1860) is re-described and illustrated in detail from laboratory-hatched material. The first zoea of H. rectirostris is more closely related to that of H. futilirostris than to H. camtschaticus, H. pandaloides, and H. geniculatus by having the pterygostomial spine and two anteroventral denticles on the carapace. The former two species, however, can be readily distinguished by the presence (H. futilirostris) or absence (H. rectirostris) of the posterolateral spine on the abdominal somites 4-5. A provisional key to the first zoeas of Heptacarpus for which larval studies are known from Korea and adjacent waters is provided. A list of larval descriptions within the Hippolytidae from Korea and adjacent waters is also included.

• Journal of the Korean Society of Propulsion Engineers
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• v.8 no.2
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• pp.32-38
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• 2004

A comprehensive understanding is given for the hot-firing test results, which were obtained throughout the verification program of mono-propellant hydrazine rocket engines (thrusters) producing 0.95 lbf (4.2 N) of nominal steady-state thrust at an inlet pressure of 350 psia (2.41 Mpa). A scrutiny for the engine performance is made in terms of thrust and temperature behavior of steady state firing mode at the given propellant injection pressures: Pinj = 400, 250, 100, and 50 psi. The thrust and specific impulse are compared with a reference performance of 1-lbf standard rocket engines and their normalization procedure is introduced. A practical engineering approach to the data measurement and reduction is addressed, too.

• Survey Research
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• v.8 no.2
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• pp.67-89
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• 2007

The Korea National Health and Nutrition Examination Survey(KNHANES) consists of Health Interview Survey, Health Behaviour Survey, Nutrition Survey, and Health Examination, and is designed to produce a broad range of descriptive health and nutritional statistics for sex and age subdomains of the population. These data can be used to measure and monitor the health and nutritional status of the population of Korea. The survey has been conducted three times from 1998. The Korea Centers for Disease Control and Prevention(KCDC) is preparing for the 4th survey which is to be conducted from 2007 through 2009. This study is to design a sample for the 4th survey. The main new feature of the sampling design is using a rolling sampling design method. Since KCDC has imposed some operational requirements, e,g., the needs of producing the annual national statistics and of year-round data collection by some regular staffs, a rolling sampling design method is introduced. This is the first time in history of applying a rolling sampling design for a national-wide large scale survey in Korea. Bringing in the rolling sampling, measurement variation due to different data collectors may be minimized.

• Korean Journal of Food Science and Technology
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• v.31 no.2
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• pp.482-487
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• 1999

Periodate-oxidized soluble starch and maltohexaose reacted with ${\alpha}-NH_2$ group of free amino acids and ${\varepsilon}-NH_2$ group of peptidyl lysine. The result shows that periodate-oxidized soluble starch and maltooligosaccharides reacted with protein and formed Schiff base between CHO group of oxidized sugar and ${\varepsilon}-NH_2$ group of surface lysine of protein molecule. Carbon and hydrogen composition of sweet potato ${\beta}-amylase$ modified with oxidized soluble starch increased and it's nitrogen composition decreased. Carbohydrate contents of sweet potato ${\beta}-amylase$ modified with oxidized soluble starch were 13.2% (pentamer), 13.4% (monomer), and with oxidized maltohexaose were 9.7% (pentamer), 9.3% (monomer) by $phenol-H_2SO_4$ method. Alpha-amino group of N-terminal, and ${\varepsilon}-NH_2$ group of lysine, of sweet potato ${\beta}-amylase$ were reacted with oxidized soluble starch by dinitrophenylation were 70% (pentamer), 73% (monomer) and 33% (pentamer), 26% (monomer), respectively, in comparison with native enzyme.