• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.146.2-146.2
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• 2014

KIST 6MV 가속기는 이온빔 분석 그리고 가속기 질량 분석법(Accelerator mass spectrometry)으로 활용된다. 이온빔 분석으로는 RBS, TOF ERD, PIXE. ${\mu}$-Probe을 할 수 있으며 AMS(Accelerator mass spectrometry)는 액체섬광측정법(LSC)과 비교할때 민감도는 1,000배 정도로 3H, 14C, 26Al,41Ca 을 10-21 ~ 10-18 mole/mg 까지 검출 가능하여. 응용분야로는 BAMS(Biological AMS), 전통과학, 지구과학, 환경과학에 활용되고 있다. 이중 AMS의 생-의학분야(BAMS)의 응용은 최근 매우 중요하게 연구되고 있다. BAMS의 활용 연구에 사용하는 핵종으로는 주로 3H, 14C, 41Ca, 36Cl를 사용하며, 14C 화합물은 쉽게 구할 수 있고, 자연방사선 이하의 낮은 14C labeled drug 사용하기 때문에 1948년 이후 생물학 연구에 혁신적으로 활용되고 있다. 주 활용분야로는 (1) 신약개발은 임상실험 전(Phase 0) 이용되며, 14C로 표지된 bio-molecule을 자연수준의 방사선 농도에서 추적자로 사용하여 질량을 측정하는 방법을 활용. (2) 의과학분야는 인체 내에서의 추적자 연구수행 (3) 항암제 연구는 암조직 중 약물농도와 암효과의 상관성을 연구 (4) 바이오 기술 분야에서는 생약 유효물질의 체내 대사연구 등을 할 수 있어 전세계적으로 활발히 연구가 진행되고 있다. KIST에서는 6MV가속기를 BAMS 연구에 활용하기 위하여 전처리 단계의 Combustion, Gas transfer, Reduction 등을 자체 제작하여 테스트 중에 있으며, BAMS 샘플의 Gas는 호기중의 성분, 대기 성분이 있으며, Liquid는 혈액(혈장,혈청,적혈구), Solid는 DNA, 세포, 장기 뼈, 피부, 식물조직, 사료, Drug 및 그 대사 류가 있다. AMS 측정 결과는 14C/12C 비율로 나타나며 그 결과를 농도로 환산하여 분석하게 된다. 또한 분석 데이터 신뢰를 확보하기 위하여 표준시료 및 품질관리용 시료를 사용하여 BAMS분석법에 대한 검증을 실시하였다.

• The Korean Journal of Financial Management
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• v.1 no.1
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• pp.119-131
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• 1985

Although Korea is short of capital technology, and natural resources, she has achieved an outstanding progress by the export-drive policies by Korean government and the creative endeavor of Korean firms. As a result of that, Korean economy and enterprises are in the same file of newly industrialized countries and Korea is ready for an economic take-off as a developed country. But in the early 1980s, each country strengthens protective trade theory and resources nationalism, and this has a great influence on the field of international trade environment. In spite of that, to continue the same high development as that of the past. Korea must try to secure and find export markets, solve trade barriers, make sure of the long-term security of resources, develop technology, and strengthen economic cooperations. To satisfy these desires by 2000s, we must try to make Korean enterprises have the global competitive power and them grow strongly among world wide firm through capital and technology accumulated during the passed years, and to do so, there must be a foreign production and marketing management, too, this can be achieved only through foreign overseas direct investment. This investment has various forms, to say, verifical integrated, horizontal integrated. conglomerate integrated forms, and the amount of investment in each country from 18 century to today reaches 500 billion dollars. This investment is done by strategic, behavioral economic, and financial motives. So I am going to approach the fields of like these; in spite of the differences among political, economical, caltural, and social systems, and many risk compared with domestic enterprises, why do Korean firms witsh to transfer the productive facilities to overseas countries and run them there? What is the comparative advantage of foreign direct investment compared with domestic investment ?. why is the factor of comparative advantage transferred through foreign direct investment?, what is the motive of foreign overseas direct investment?, and last the ownership-specific factors and the theory of internalization, and the location specific factors were analysed chiefly. But in consideration of the given condition in Korea, Korean overseas direct investment must be propelled rationally on the basis of the above mentioned theory.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.37 no.12
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• pp.1184-1191
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• 2009

In order to reduce the download around the Smart UAV(SUAV) at Transition mode, flow control using synthetic jet has been performed. Many of the complex tilt rotor flow features are captured including the leading and trailing edge separation, and the large region of separated flow beneath the wing. Based on the results of part 1 of the present work, synthetic jet is located at 0.01c, $0.95c_{flap}$ and it is operated with the non-dimensional frequency of 0.5, 5 to control the leading edge and trailing edge separation. Consequently, download is substantially reduced compared to with no control case at transition mode using leading edge jet only. The present results show that the overall flight performance and stability of the SUAV can be remarkably improved by applying the active flow control strategy based on synthetic jet.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.37 no.12
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• pp.1173-1183
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• 2009

In order to reduce the download around the Smart UAV(SUAV) at hovering, flow control using synthetic jet has been performed. Many of the complex tilt rotor flow features are captured including the leading and trailing edge separation, and the large region of separated flow beneath the wing. In order to control the leading edge and trailing edge separation, synthetic jet is located at 0.01c, $0.3c_{flap}$, $0.95c_{flap}$. As non-dimensional frequency, the flow pattern is altered and the rate of drag reduction is changed. The results show that synthetic jets shorten the vortex period and decrease the vortex size by changing local flow structure. By using leading edge jet and trailing edge jet, download is efficiently reduced compared to no control case at hovering mode.

• Korean Journal of Pharmacognosy
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• v.7 no.3
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• pp.199-208
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• 1976

저자(著者)등은 1976년(年) 7월(月) 17일(日)부터 동년(同年) 11월(月) 14일(日)까지의 기간(期間)동안 서울과 경기도내(內) 5개지역(서울 : 관악산, 경기도 : 수원, 광릉, 갈매리, 오산리)으로부터 100여 종(種)의 한국산(韓國産) 고등균류(高等菌類)를 채집하였으며, 이중 31종(種)을 분류(分類) 확인(確認)하였다. 분류(分類)된 31종중(種中) 9종(種) 즉 (1) Scutellinia scutellata $(St.\;A_{MANS})$ $L_{AM}$ (2) Peziza vesiculsa $F_{R}.$ (3) Helvella atra $F_{R}.$ (4) Neobulgaria pura $(P_{ERS}.)$ $P_{ETRAK}$ (5) Trametes coccinea $F_{R}.$ (6) Amanita melleiceps $H_{ONGO}$ (7) Cotylidia burtina $(P_{T}.)$ $I_{MAZ}.$ (8) Sarcodontia copelandii $(P_{AT}.)$ $I_{MAZ}.$ comb nov. (9) Sphaerobolus stellatus $P_{ERS}.$은 한국 미기록종(種)이며, 이외에 2종(種) (1) Lycoperdon D.M.C-2 및 (2) Tuber melanosporum도 잠정적으로 미기록종(種)이라 사료된다. 한편 Neobulgaria pira $P_{ERS}.$가 속해있는 과(科)인 Helotiaceae와 Sphaerobolus stellatus $P_{ERS}.$가 속해있는 과(科)인 Sphaerobolaceae는 각각(各各) 한국 미기록과(科)이다. 이에 저자등은 이들에게 신칭을 붙여 각각(各各)의 외부(外部)형태와 현미경적 특징에 대하여 기술하고, 이들의 사진과 함께 보고 하는 바이다.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.9 no.1
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• pp.66-70
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• 1998

Background and Objectives : The managements of unilateral vocal cord palsy include type Ⅰ thyroplasty and arytenoid adduction. One type operation has been shown no satisfactory effect. We evaluated preoperative and postoperative speech of unilateral vocal cord palsy patients who received combined operation of type Ⅰ thyroplasty and arytenoid adduction to help for the management plan of unilateral vocal cord palsy patients. Materials and Methods : We reviewed the postoperative results and complication of 17 surgically treated patients of unilateral vocal cord palsy at Severance hospital from Nov. 1996 to Dec. 1997 retrospectively. They were received combined operation of type Ⅰ thyroplasty and arytenoid adduction. Their pre and post-operative speech were analyzed with MDVP(Multi-Dimension-Voice analysis Program) of CSL(Computerized Speech Lab). Results : After the operation, MPT(Maximal Phonation Time) was increased and MFR(Mean Flow Rate) was decreased in all patients. NHR(Noise to Harmonic Ratio) and VTI(Voice Turbulence Index) were decreased : liner, RAP(Relative Average Perturbation Quotient), PPQ(Pitch Period Perturbation Quotient), sPPQ(smoothed Pitch Period Perturbation Quotient), vFo(fundamental frequency Variation) were decreased : Shimmer, APQ(Amplitude Perturbation Quotient), sAPQ(Smoothed Amplitude Perturbation Qoutient), vAm(Peak Amplitude Variation) were decreased in all the patients. Conclusions : In unilateral vocal cord pals), combined operation of type Ⅰ thyroplasty and arytenoid adduction could obtain satisfactory postoperative voice. MDVP has many parameters and good method for evaluation of voice surgery.

• The Journal of Korean Physical Therapy
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• v.21 no.2
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• pp.109-116
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• 2009

Purpose: $17\beta$-estradiol is the most active endogenous estrogen, which is related to favorable changes in the plasma lipid profile, to relaxation of the coronary vessels, and to a decrease in platelet aggregation and vascular smooth muscle cell migration. However, although the beneficial effect of estrogens on plasma lipoproteins (ie, lowering low-density lipoprotein and increasing high-density lipoprotein cholesterol) contributes to cardiovascular protection, it does not fully account for the protective effect, particularly in the application of physical therapy, including low frequency electrical stimulation. Methods: The aim of this study was to demonstrate the inhibition of stressors, such as endothelin-1 (ET-1), serotonin (5-hydroxytryptamine, 5-HT), prostaglandin $F2\alpha$ ($PGF2\alpha$), and a protein kinase C (PKC) activator 12-deoxyphorbol 13-isobutyrate (DPB), induced isometric tension by $17\beta$-estradiol in vascular smooth muscle strips, respectively. In addition, the effects of low frequency electrical stimulation at the meridian points (CV-3, -4, Ki-12, SP-6, LR-3, BL-25, -28, -32, -52) on the indirect antihypertensive effect were examined by monitoring the changes in the serum $17\beta$-estradiol concentration in healthy volunteers. Results: Isometric tension analysis showed that the responses of inhibited tension by $17\beta$-estradiol were similar to the same stressors in rat aortic smooth muscle strips. Furthermore, although the continued amplitude modulation (AM) type of electrical stimulation was not increased significantly by electrical stimulation, the current of the frequency modulation (FM) type of low frequency electrical stimulation increased the serum $17\beta$-estradiol concentration in normal volunteers. Conclusion: These results, in part, suggest that $17\beta$-estradiol has the capacity to supress stressor-induced muscle tension, and electrical stimulation, particularly current of the FM type, has a modulatory effect on the sex steroid hormones, particularly $17\beta$-estradiol, in healthy volunteers.

• Proceedings of the KSRS Conference
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• 1998.09a
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• pp.301-306
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• 1998

Korea Aerospace Research Institute (KARI) is developing a Korea Multi-Purpose Satellite I (KOMPSAT-I) which accommodates Electro-Optical Camera (EOC), Ocean Scanning Multi-spectral Imager (OSMI), and Space Physics Sensor (SPS). The satellite has the weight of about 500kg and will be operated on the 10:50 AM sun-synchronized orbit with the altitude of 685 km. The satellite will be launched in 1999 and its lifetime is expected to be over 3 years. The main mission of EOC is the cartography to provide the images from a remote earth view for the production of 1/25000-scale maps of KOREA. EOC collects 510 ~ 730 nm panchromatic imagery with the ground sample distance(GSD) of 6.6 m and the swath width of 17 km by push broom scanning. EOC also can scan $\pm$45 degree across the ground track using body pointing method. The primary mission of OSMI is worldwide ocean color monitoring for the study of biological oceanography. It will generate 6 band ocean color images with 800 km swath width and 1km GSD by whiskbroom scanning. OSMI is designed to provide on-orbit spectral band selectability in the spectral range from 400 nm to 900 nm through ground command. This flexibility in band selection can be used for various applications and will provide research opportunities to support the next generation sensor design. SPS consists of High Energy Particle Detector (HEPD) and ionosphere Measurement Sensor (IMS). HEPD has missions to characterize the low altitude high-energy Particle environment and to study the effects of radiation environment on microelectronics. IMS measures densities and temperature of electrons in the ionosphere and monitors the ionospheric irregularities at the KOMPSAT orbit.

• Journal of the Korean Society of Earth Science Education
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• v.8 no.1
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• pp.66-75
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• 2015

This study is to investigate an argumentation level for elementary school students after analysing an argumentation structure about a socio scientific issue(SSI), and inquire a change of the decision-making according to the refutation materials and empathic situation. This data was collected from the semi-structured interview with the 14 students, grade 6th. For this, the first stage is to present the reading materials about the SSI to the students, let them decision-making and make them argue pro and con about the SSI during the interview. After that, facing with the refutation materials against the existing contention and the empathic situation, the change of the decision-making of the students was conducted. After the research, the level of the argumentation of the students was low, and the students who didn't have the background knowledge about the theme made the decisions according to the values, emotions or intuitions of their own. And the decision-making of the students changed more when presented with the refutation materials and the empathic situation, they were difficult to make the decision because of new information and various stances. Besides, they lacked in the ability that recognize the situation related with their own life, just used the fragmentary knowledge associated with value of life respect. Through these result, it is necessary to produce the refutation materials and empathic materials about the SSI to the students for improving the level of argumentation.

• Applied Microscopy
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• v.46 no.1
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• pp.58-66
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• 2016

Thymosin ${\beta}4$ ($T{\beta}4$) has been recently reported to play a role in dentinogenesis by regulating the expression of dentin matrix proteins. Based on previous studies, it is hypothesized that $T{\beta}4$ is associated with the formation of the enamel matrix and thus plays an important role in ameloblast. However, there is no report on the function of $T{\beta}4$ during tooth development so far. Therefore, in this study, we aimed to investigate the expression of $T{\beta}4$ and its function in ameloblasts during mouse tooth development. $T{\beta}4$ was expressed strongly in the tooth bud at the bud stage and in the dental lamina and oral epithelium at the cap stage. In advanced bell stage at postnatal day 4, large elongated ameloblasts were observed and the expression of the $T{\beta}4$ protein was the highest, with the enamel being was thicker than that in the early bell stage. The length of ameloblasts increased from the presecretory to the secretory stage and decreased from the maturation to the protective stage. These results suggest that $T{\beta}4$ participates not only in the proliferation of oral epithelial cells during the early stage of tooth development but also regulates enamel protein secretion in ameloblasts and enamel mineralization.