• Bulletin of the Korean Chemical Society
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• 제28권1호
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• pp.41-48
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• 2007

Large colorless single crystals of sodium zeolite X, stoichiometry |Na80 |[Si112Al80O384]-FAU, with diameters up to 200 μm and Si/Al = 1.41 have been synthesized from gels with the composition of 2.40SiO2 : 2.00NaAlO2 : 7.52NaOH : 454H2O : 5.00TEA. One of these, a colorless octahedron about 200 μm in cross-section has been treated with aqueous 0.1 M KNO3 for the preparation of K+-exchanged zeolite X. The crystal structure of |K80|[Si112Al80O384]-FAU per unit cell, a = 24.838(4) A, dehydrated at 673 K and 1 × 10-6 Torr, has been determined by single-crystal X-ray diffraction techniques in the cubic space group Fd at 294 K. The structure was refined using all intensities to the final error indices (using only the 707 reflections for which Fo > 4σ (Fo)) R1 = 0.075 (based on F) and R2 = 0.236 (based on F2). About 80 K+ ions per unit cell are found at an unusually large number of crystallographically distinct positions, eight. Eleven K+ ions are at the centers of double 6-rings (D6Rs, site I; K-O = 2.492(6) A and O-K-O (octahedral) = 88.45(22)o and 91.55(22)o). Site-I' position (in the sodalite cavities opposite D6Rs) is occupied by five K+ ions per unit cell; these K+ ions are recessed 1.92 A into the sodalite cavities from their 3-oxygen planes (K-O = 2.820(19) A, and O-K-O = 78.6(6)o). Twety-three K+ ions are found at three nonequivalent site II (in the supercage) with occupancies of 5, 9, and 9 ions; these K+ ions are recessed 0.43 A, 0.75 A, and 1.55 A, respectively, into the supercage from the three oxygens to which it is bound (K-O = 2.36(13) A, 2.45(13) A, and 2.710(13) A, O-K-O = 116.5(20)o, 110.1(17)o, and 90.4(6)o, respectively). The remaining sixteen, thirteen, and twelve K+ ions occupy three sites III' near triple 4-rings in the supercage (K-O = 2.64(3) A, 2.94(3) A, 2.73(5) A, 2.96(6) A, 3.06(4) A, and 3.08(3) A).

• Asian Pacific Journal of Cancer Prevention
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• 제17권3호
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• pp.1519-1529
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• 2016

Background: Matrix metalloproteinase -2 (gelatinase-A, Mr 72,000 type IV collagenase, MMP-2) and -9 (gelatinase-B, Mr 92,000 type IV collagenase, MMP-9) are key molecules that play roles in tumor growth, invasion, tissue remodeling, metastasis and stem-cell regulation by digesting extracellular matrix barriers. MMP-2 and -9 are well known to impact on solid cancer susceptibility, whereas, in hematological malignancies, a paucity of data is available to resolve the function of these regulatory molecules in bone marrow mononuclear cells (BM-MNCs) and stromal cells of myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML). Objectives: The present study aimed to investigate mRNA expression and gelatinase A and B secretion from BM-MNCs in vitro and genotypic associations of MMP-2 (-1306 C/T; rs243865), MMP-9 (-1562 C/T; rs3918242), tissue inhibitor of metalloproteinase -1 (TIMP-1) (372T/C; rs4898, Exon 5) and TIMP-2 (-418G/C; rs8179090) in MDS and AML. Results: The study covered cases of confirmed MDS (n=50), AML (n=32) and healthy controls (n=110). MMP-9 mRNA expression revealed 2 fold increased expression in MDS-RAEB II and 2.5 fold in AML M-4 (60-70% blasts). Secretion of gelatinase-B also revealed the MMP-9 mRNA expression and ELISA data also supported these data. We noted that those patients having more blast crises presented with more secretion of MMP-9 and its mRNA expression. In contrast MMP-9 (-1562 C/T) showed significant polymorphic associations in MDS (p<0.02) and AML (p<0.02). MMP-9 mRNA expression of C/T and T/T genotypes were 1.5 and 2.5 fold increased in MDS and AML respectively. In AML, MMP-2 C/T and T/T genotypes showed 2.0 fold mRNA expression. Only MMP-9 (-1306 C/T) showed significant 4 fold (p<0.001) increased risk with chemical and x-ray exposed MDS, while tobacco and cigarette smokers have 3 fold (p<0.04) risk in AML. Conclusions: In view of our results, MMP-9 revealed synergistic secretion and expression in blast crises of MDS and AML with 'gene' polymorphic effects and is significantly associated with increased risk with tobacco, cigarette and environmental exposure. Release and secretion of these enzymes may influence hematopoietic cell behavior and may be important in the clinical point of view. It may offer valuable tools for diagnosis and prognosis, as well as possible targets for the treatments.

• 지적과 국토정보
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• 제50권2호
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• pp.169-187
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• 2020

한국에는 1975년부터 내무부의 연구보고에 의하여 스위스는 지적제도와 등기제도를 통합하여 운영하는 국가로 알려져 왔다. 그러나 필자가 스위스의 지적제도와 등기제도가 국방·시민보호·체육부와 법무·경찰부에서 분리하여 관장하고 있는 것을 발견하였다. 따라서 스위스의 지적제도와 등기제도의 담당기관은 어디이며, 관련 법령은 무엇이고, 관련 공적 도부는 어떤 것이 있는가에 대한 의문을 갖게 되었으며, 이를 해소하는 것이 본 연구의 배경이며 목적이다. 연구결과 첫째, 지적사무는 국방·시민보호·체육부 소속 연방지형사무소의 지적측량국에서 담당하고, 등기사무는 법무·경찰부 소속 연방법무사무소의 사법국에서 담당하고 있으며 둘째, 지적관련 법률은 1993년에 새로이 제정한 'VAV'와 'TVAV' 등이 있고, 등기관련 법률은 1912년부터 시행한 '민법(ZGB)'과 '토지등기부에 관한 명령(GbVO) 등이 있으며 셋째, 지적공부는 부동산등록부·지적도·수치지적부 등이 있고, 등기부는 주장부·일기장·평면도·부동산기술서 등이 있다. 본 연구결과가 스위스의 지적제도는 국방·시민보호·체육부에서, 등기제도는 법무·경찰부에서 각각 분리하여 관장하고 있다는 사실을 명확하게 이해할 수 있기를 기대한다.

• 천문학논총
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• 제30권2호
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• pp.559-563
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• 2015

Monitor of All-sky X-ray Image (MAXI) is a Japanese X-ray all-sky surveyer mounted on the International Space Station (ISS). It has been scanning the whole sky since 2009 during every 92-minute ISS rotation. X-ray transients are quickly found by the real-time nova-search program. As a result, MAXI has issued 133 Astronomer's Telegrams and 44 Gamma-ray burst Coordinated Networks so far. MAXI has discovered six new black holes (BH) in 4.5 years. Long-term behaviors of the MAXI BHs can be classified into two types by their outbursts; a fast-rise exponential-decay type and a fast-rise flat-top one. The slit camera is suitable for accumulating data over a long time. MAXI issued a 37-month catalog containing 500 sources above a ~0.6 mCrab detection limit at 4-10 keV in the region ${\mid}{b}{\mid}$ > $10^{\circ}$. The SSC instrument utilizing an X-ray CCD has detected diffuse soft X-rays extending over a large solid angle, such as the Cygnus super bubble. MAXI/SSC has also detcted a Ne emission line from the rapid soft X-ray nova MAXI J0158-744. The overall shapes of outbursts in Be X-ray binaries (BeXRB) are precisely observed with MAXI/GSC. BeXRB have two kinds of outbursts, a normal outburst and a giant one. The peak dates of the subsequent giant outbursts of A0535+26 repeated with a different period than the orbital one. The Be stellar disk is considered to either have a precession motion or a distorted shape. The long-term behaviors of low-mass X-ray binaries (LMXB) containing weakly magnetized neutron stars are investigated. Transient LMXBs (Aql X-1 and 4U 1608-52) repeated outbursts every 200-1000 days, which is understood by the limit-cycle of hydrogen ionization states in the outer accretion disk. A third state (very dim state) in Aql X-1 and 4U 1608-52 was interpreted as the propeller effect in the unified picture of LMXB. Cir X-1 is a peculiar source in the sense that its long-term behavior is not like typical LMXBs. The luminosity sometimes decreases suddenly at periastron. It might be explained by the stripping of the outer accretion disk by a clumpy stellar wind. MAXI observed 64 large flares from 22 active stars (RS CVns, dMe stars, Argol types, young stellar objects) over 4 years. The total energies are $10^{34}-10^{36}$ erg $s^{-1}$. Since MAXI can measure the spectrum (temperature and emission measure), we can estimate the size of the plasma and the magnetic fields. The size sometimes exceeds the size of the star. The magnetic field is in the range of 10-100 gauss, which is a typical value for solar flares.

• 한국미생물학회:학술대회논문집
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• 한국미생물학회 2005년도 International Meeting of the Microbiological Society of Korea
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• pp.143-147
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• 2005

The non-pathogenic, non-glycopeptide-producing actinomycete Streptomyces coelicolor carries a cluster of seven genes (vanSRJKHAX) that confers inducible, high-level resistance to vancomycin. The van genes are organised into four transcription units, vanRS, vanJ, vanK and vanHAX, and these transcripts are induced by vancomycin in a vanR-dependent manner. vanHAX are orthologuous to genes found in vancomycin resistant enterococci that encode enzymes predicted to reprogramme peptidoglycan biosynthesis such that cell wall precursors terminate in D-Ala-D-Lac, rather than D-Ala-D-Ala. vanR and vanS encode a two-component signal transduction system that mediates transcriptional induction of the seven van genes. vanJ and vanK are novel genes that have no counterpart in previously characterised vancomycin-resistance clusters from pathogens. VanK is essential for vancomycin resistance in S. coelicolor and it is required for adding Gly branch to stem peptides terminating D-Ala-D-Lac. Because VanK can recognise D-Lac-containing precursors but the constitutively expressed femX enzyme, encoded elsewhere on the chromosome, cannot recognize D-Lac-containing precursors as a substrate, vancomycin-induced expression of VanHAX in a vanK mutant is lethal. Further, femX null mutants are viable in the presence of glycopeptide antibiotics but die in their absence. Bioassay using vanJp-neo fusion reporter system also showed that all identified inducers for van genes expression were glycopeptide antibiotics, but teicoplanin, a membrane-anchored glycopeptide, failed to act as an inducer.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2002년도 ITC-CSCC -2
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• pp.1296-1299
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• 2002

We implemented a CD signal processor operated on a CAV 48-speed CD-ROM drive into a VLSI. The CD signal processor is a mixed mode monolithic IC including servo-processor, data recovery, data-processor, and I-bit DAC. For servo signal processing, we included a DSP core, while, for CAV mode playback, we adopted a PLL with a wide recovery range. Data processor (DP) was designed to meet the yellow book specification.［2］So, the DP block consists of EFM demodulator, C1/C2 ECC block, audio processor and a block transferring data to an ATAPI chip. A modified Euclid's algorithm was used as a key equation solver for the ECC block To achieve the high-speed decoding, the RS decoder is operated by a pipelined method. Audio playability is increased by playing a CD-DA disc at the speed of 12X or 16X. For this, subcode sync and data are processed in the same way as main data processing. The overall performance of IC is verified by measuring a transfer rate from the innermost area of disc to the outermost area. At 48-speed, the operating frequency is 210 ㎒, and this chip is fabricated by 0.35 um STD90 cell library of Samsung Electronics.

• 대한전자공학회논문지TC
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• 제49권5호
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• pp.15-20
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• 2012

본논문을 통해, 리드솔로몬 복호기에서 매우 복잡한 나누기회로를 사용않고, 오류위치를 찾아내는 치엔기기의 최적설계기법을 제시했다. 최적화는 매우 간단한 제곱/4제곱회로를 사용하고, 병렬처리를 통해 가능했다. 이법은 현대 디지털 통신및/가전기기 대부분에 응용되질수 있다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1992년도 하계학술대회 논문집 B
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• pp.1260-1262
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• 1992

We have developed an optical switch array, which consists of 16X8 reflective symmetric self electrooptic effect devices(RS-SEED), from MOCVD-grown GaAs/AlGaAs low-barrier(LB) multiple quantum well (MQW) structures.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2000년도 제15차 학술회의논문집
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• pp.101-101
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• 2000

MSC(Multispectral Camera), which will be a unique payload on KOMPSAT-II, is designed to collect panchromatic and multi-spectral imagery with a ground sample distance of 1m and a swath width of 15km at 685km altitude in sun-synchronous orbit. The instrument is designed to have an orbit operation duty cycle of 20% over the mission life time of 3 years. MSC electronics consists of three main subsystems; PMU(Payload Management Unit), CEU(Camera Electronics Unit) and PDTS(Payload Data Transmission Subsystem). PMU performs all the interface between spacecraft and MSC, and manages all the other subsystems by sending commands to them and receiving telemetry from them with software protocol through RS-422 interface. CEU controls FPA(Focal Plane Assembly) which contains TDI(Timc Delay Integration) CCD(Charge Coupled Device) and its clock drivers. PMU provides a Master Clock to synchronize panchromatic and multispectral camera. PDTS performs compression, storage and encryption of image data and transmits them to the ground station through x-band.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2014년도 추계학술대회 논문집
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• pp.260-261
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• 2014

$TiO_2$ nanotubes (TNT) synthesized by microwave-assisted hydrothermal method by using $TiO_2-P25$ as a precursor at hydrothermal temperature $150^{\circ}C$ in 4 hours. The concentration of alkaline solution is between 4M and 10M. Samples were characterized by X-ray diffraction (XRD), Raman spectroscopy (RS), Transmission electron microscopy (TEM), Brunauer-Emmett-Teller (BET) and UV-vis DRS spectroscopy. The results demonstrated the effects of the alkali concentration to the formation of nanotubes. The photocatalytic activity was investigated by degradation of Methylene Blue (MB).