기원전 5세기의 보령군 평라리 출토의 유리구슬에 대하여

최주,이융조,정동찬,홍현선,윤용현,김수철,송종한,변종홍 한국전통과학기술학회 1996 한국전통과학기술학회지 Vol.3 No.1

A dark blue glass bead covered with a thick white weathered layer was unearthed from a grave at Pyoungra-ri, Boryoung-gun, Choongcheong Province in 1995. The grave was dated to be at least around the 5th century BC as determined by other archaeological artifacts accompanied. This dating indicates that they bead is the earliest glass item excavated so far in the Korean Peninsula and as old as the earliest Chinese glass artifacts. The glass bead is 17.4 mm in diameter and 15.:3 mm high with a bore of 2mm. Chemical composition at the dark blue broken surface was analyzed by Rutherford Back Scattering(RBS) method using 2MV Tandem-type accelerator, and found to be 77.7% Si0₂. 11.5% K₂O, 2.4 CaO, 3.6%, Al₂O₃ 0.4% MgO, 1.3%, MnO, 0.6% Fe₂O₃. 0.8% CuO, and 1.7 PbO. Small amount of lead oxide in the bead is unique: because lead oxide is hardly observed in such a potash glass from other countries of this period. Furtherniore, the lead isotope ratio indicates that the raw materials are originated from the southern part of Korea. The remains, where prehistorical beads made of jades or glasses are being excavated, were concentrated in the area that Pyoungra-ri is located and the native culture of this area was highly developed at the period of around 5th century BC. These facts is do not exclude the possibility that the local discovery of the Pyoungra-ri glass bead may be a local invention.

한국 최초의 경주시 황남동 출토 유리 용융 도가니 및 유리 구슬에 대한 연구

최주,안재호,황상주,권희경,김수철,도정만,박기훈,김선태 한국전통과학기술학회 1994 한국전통과학기술학회지 Vol.1 No.1

A piece of glass melting crucible whose inner face was lined with yellowish brown glass, a yellowish brown ellipsoidal bead and a greenish scrcew-shaped wound bead were unearthed in Kyongju city. These finds were dated to around the middle of the 6th century by pattern impressed earthenwares excavated in the same stratum. Chcmica analyses were carried out by means of energy diapersive spectrometry(EDS), atomic absorption analysis(AA), induced coupling plasma analysis(ICP) along with conventional wet analvsis. Also X-ray and elecrtron diffraction analvses were periomd in an attempt to identify any crystalline precipitates. Three glass items are classified iota lead-silica group showing the same compositions. This indicates that the two beads are from the same crucible. Ywllowish brown glass film contains 72.5% PbO and 25.2% SiO₂ and its softening point is 442℃ which is determined by differential scanning calorimeter(DSC). Melting point is found to be around 650℃ by practical measurement. Color differences in two beads are proved to be mainly due to copper contained in the glass, i.e., yellowish brown and greenish colors depend on reduction and oxidation atmosphere during melting, respectively. Chemical analysis shows that the glass melting crucible is a common earthenware.

오주연문장전산고에 따른 제철복원실험

최주,김유형,김수철,백종현,김종원,김영도 한국전통과학기술학회 1994 한국전통과학기술학회지 Vol.1 No.1

In this investigation, furnace was constructed on the basis of old Korean reference published in early 19C by Kyukyung Lee entitled $quot;Oju Yunmun Jangjeon Sango$quot; and irons were obtained by smelting process. It is believed that the restoration of the ancient iron making process will help to understand the principle of the ancient iron making process. The furnace was constructed with clay and nine tuyers were installed in one side of the furnace. Ore lumps were obtained by the use of iron ore and oak tree charcoal. Temperature and atmosphere of the furnacc were controlled during smelting process. For refining, ore lumps from this furnace were melted by charcoal refining furnace or by induction furnace. Forging was performed for refined blooms. Smelting process was studied through the microstructures and chemical analyses of the produced slags and iron pieces. Since ores from Dalcheon mine close to Koungju were used, the results from this experiment will give great contribution to appraise abundant iron remains of Shilla dynasty excavated in Kyongju area and to identify whether excavated furnace is smelting or melting furnaces.

Skin reflectance법에 의한 신생아 bilirubin측정의 실험연구

류정록,이승관,이창규,최명제,장철수 高麗大學校 倂設 保健大學 保健科學硏究所 1994 保健科學論集 Vol.20 No.1

Spectral reflectance measurements on the newborn skin provide a noninvasive screening method for neonatal jaundice and may also be useful in assessing the efficacy of phototherapy and the potential for kernicterus. In this study we briefly discussed about the bilirubin metabolism and determination of serum bilirubin by spectral reflectance of the skin. A correlation study was conducted accross Minolta jaundice meter with AO bilirubinometer as the reference assay. The correlation statistics obtained for 43 newborns were: Minolta jaundice meter (chest site) =0.810 AO bilirubinometer+7.137, correlation coefficient+0.41, Minolta jaundice meter(forehead site) = 0.887 AO bilirubinometer+8.026, correlation coefficient = 0.38. Studies from linear relationship statistics showed some evidence for the difference between two methods. It had been suggested that a noninvasive method for serum bilirubin by skin reflectance was not compatible with the AO bilirubinometer.

Fly ash - Dolomite - Limestone 조성들을 이용한 섬유화의 방사경향

양현수,최웅재,정주식 한국공업화학회 1998 응용화학 Vol.2 No.2

To study the fiber manufacturing used to coal fly ash, melting behavior of fly ash and mixed minerals were studied with coal ash sample (sub-bituminous coal). Minerals used to Limestone and Dolomite. Limestone[including CaO(50∼60wt%)] and Dolomite [including MgO(30∼40wt%)] are reacted fluxing agents. By using the proper composition, melting temperature and fibrous temperature are decreased. It should be seem that silicate and aluminosilicate are dissolved in inserting fluxing agents. Therefore, the composition of fluxing agents in the sample, fibrous temperature and melting temperature gave rise to a great effect on the physical properties of fiber manufacturing. Tests of the manufactured fiber were measured for the diameter(10∼25㎛), tensile strength (200∼350 ㎏/㎟) and Young's Modulus(5000∼6000 ㎏/㎟).

40Gbps급 (4X10) VCSEL Array 구동기

김형수,정성재,김두근,이희현,최영완 중앙대학교정보통신연구소 2001 정보통신연구소논문집 Vol.3 No.2

본 논문에서는 VCSEL(Vertical Cavity Surface Emiting Laser)을 채널당 1Gbps로 동작시키고, DC Bias 전류 변화폭과 RF Modulation 전류 변화폭의 조절이 가능한 구동 드라이버를 현대 0.35㎛ 2-Poly 4-Matel CMOS공정을 이용하여 설계했다. In this paper, we present a 40 Gb/s VCSEL driver (4 x 10 channels, 1 Gbps/ch) designed and fabricated in HYNIX 0.35㎛ 2-poly 4-matel CMOS technology. The CMOS driver designed for a free space optical interconnect system is consisted of two NMOS for driving a VCSEL and protection circuit rejecting influence of electro-static discharge (ESD) or unexpected input signal with several tens voltage amplitude. Two NMOS with CMOS channel length of 0.4㎛ and width of 100 ㎛ are used for adjusting dc bias current from 0 to 27 mA and ac modulation current from 0 to 13.8 mA. Protection circuit is made of two diodes. The purpose of the protection circuit is to permit the input modulation voltage range only from 5 to 5 V.

구기자 및 구기엽 추출물의 피부과색소 조절효과

김동희 ( Dong Hee Kim ),이수연 ( Soo Yeon Lee ),김남경 ( Nam Kyung Kim ),윤보경 ( Bo Kyung Youn ),정다솜 ( Da Som Jung ),최은영 ( Eun Young Choi ),홍소리 ( So Ri Hong ),윤지영 ( Ji Young Yoon ),강명화 ( Myung Hwa Kang ),이진영 ( J 한국응용생명화학회(구 한국농화학회) 2011 Journal of Applied Biological Chemistry (J. Appl. Vol.54 No.4

구기자, 건조구기엽, 생구기엽 추출물의 미백효과를 검증하였다. Tyrosinase 저해활성 측정결과 건조구기엽 에탄올추출물 500 μg/mL에서 44%의 저해활성을 나타내었으며, melanoma cell (B16F10)에서의 melanin 생합성 저해율 측정결과 건조구기엽 에탄올 추출물 50 μg/mL에서 14%의 저해효과를 나타내었다. 구기자, 건조구기엽, 생구기엽 추출물을 처리한 B16F10군 에서는 tyrosinase protein의 발현이 처리하지 않은 군보다 감소 하였다. 특히, 건조구기엽 추출물의 경우 tyrosinase의 단백질 발현량을 많이 저해하였다. 결과적으로 건조구기엽 추출물의 미백활성이 가장 우수하였으며, 식품 및 화장품의 기능성 소재로 이용이 가능할 것으로 판단된다. The objective of the present study was to evaluate the skin whitening effect of the extracts, Lycii fructus (LF), Dry-L. foilum (DLF) and Fresh-L. folium (FLF). Tyrosinase inhibition activities was 44% in DLF ethanol extracts at a 500 μg/mL. When the tyrosinase activities in B16F10 murine melanoma cell were tested, the activities in DLF ethanol extracts was 14% at a 50 μg/mL concentration. The protein expression of microphthalmia-associated transcription factor, tyrosinase related protein 1 (TRP-1), TRP-2, and tyrosinase, which are all melanin related factors, showed that LF, DLF and FLF extracts inhibited the protein bio-synthesis in B16F10 melanoma cell. Especially the DLF extract showed greater decrease of protein expressions. Results indicate that the DLF extract tested in the present study had skin whitening activity and can be used as a function a ingredients for food and cosmetic compositions.

Loss of Heterozygosity on Chromosome 10, 13q(Rb), 17p, and p53 Gene Mutations in Human Brain Gliomas

Seung Hoo Lee Korean Academy of Medical Science 1995 Journal of Korean medical science Vol.10 No.6

다발성 원격전이와 SIADH를 동반한 원발성 충수돌기 악성유암종 (Carcinoid Tumor) 1예

안광진,정현철,노재경,박중원,이화영,서창옥,노준규,이종태,최수임,김병수 대한내과학회 1990 대한내과학회지 Vol.38 No.1

Carcinoid tumors are the most trequently occurring neoplasms of the appendix and small bowel. Most carcinoid tumors of the appendix are incidentally discovered during other surgical procedures. Its natural course is usually benign and the size of the tumor is closely related with the liability of regional or distant metastasis, so this affects the mode of therapy. Lesions less than 2㎝ in greatest dimension are never shown to have metastatic lesions and those larger than 2㎝ are likely to metastasize to regional lymph nodes and occasionally to distant organs such as liver, lung and bones. We experienced a malignant carcinoid tumor of the appendix with metastasis to regional lymph nodes, lung, ribs and thoracic vertebrae, cervical lymphnodes, and the right adrenal gland without liver metastasis. The patient had no signs of carcinoid syndrome but showed hyponatremia which was corrected by fluid restriction, suggesting SIADH. The patient was treated with a combination regimen of 5-fluorouracil and doxorubicin after surgical removal of the appendiceal mass, and a palliative radiotherapy for the osteolytic lesion of the right 12th rib. A review of our experience suggests a more extensive program in disseminated malignant carcinoid tumors is required.

Novel control of plasma expansion direction aimed at very low pressure laser-induced plasma spectroscopy.

Choi, Soo-Jin,Choi, Jae-Jun,Yoh, Jack J Optical Society of America 2015 Optics express Vol.23 No.5

<P>A plasma confinement approach has been applied to enhance the signal intensity of laser-induced plasma in low pressure conditions down to 10(-2) torr. Detection of plasma emission spectrum is a daunting task at low pressure due to the low electron density and the short persistence time of plasma that undergoes a rapid expansion. Here we devised a spatial confinement setup that increases the electron density at various range of low pressures. A confining window is placed above the sample surface to control the direction of the expanding plasma aimed at optimizing the efficiency of the low pressure detection. More ions, atoms, and molecules can reach the detector by a direction-controlled confinement of an otherwise freely expanding plasma. The spectral intensities of neutral atoms increased up to 4 times with a single laser pulse by the proposed confining method at 1 torr. The signal of doubly ionized carbon atom which was detectable only at low pressure is also enhanced 4 times. The results of this study provide an important guideline for strengthening the otherwise weak signals at low pressure by controlling the plasma expansion direction.</P>