• Proceedings of the IEEK Conference
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• 2005.11a
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• pp.885-888
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• 2005

In this study, we designed an ARM9 compatible RISC microprocessor using VHDL. The microprocessor was designed to support Harvard architecture with separate instruction cache and data cache. The state machine was optimized for multi-cycle instructions. In addition, a data forwarding mechanism was adopted to reduce the stall cycles due to data hazards. Assembly programs were up-loaded into a ROM block for system-level simulation. Proper operation of the designed microprocessor was confirmed by investigating the contents of the internal registers as well as the RAM block. Futhermore, the simulation results clearly indicated that the operation speed of the processor designed in this study is enhanced by reducing the execution cycles required for multiplication related instructions.

• Journal of Microbiology and Biotechnology
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• v.16 no.6
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• pp.961-964
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• 2006

GDP-mannosyltransferase (GMT) is an enzyme responsible for the addition of a mannose to glucose ($\alpha$[1$\rightarrow$3]) during biosynthesis of the water-soluble branched polysaccharide acetan in Acefobacter species. In an effort to obtain a cellulose-overproducing bacterium, a mutant defective in GMT of Acetobacter xylinum KCCM 10100 was constructed by single crossover homologous recombination using part of the aceA gene encoding GMT amplified by polymerase chain reaction. The GMT-disrupted mutant produced 23% more cellulose, but 16% less water-soluble polysaccharide than those of the wild-type strain. Analysis of the sugar composition by gel permeation chromatography revealed that water-soluble polysaccharides produced by the GMT-defective mutant contained no mannose molecule.

• Journal of Acupuncture Research
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• v.21 no.5
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• pp.149-162
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• 2004

Quality assurance with high safety profile is one of the most critical issues to medical device manufacturing. In general, this issue was not paid proper attention with respect to acupuncture needle and its related devices. Acupuncture needles are manufactured through various standards ranging from purely hand-made, partially hand-made and partially machine-made, to fully machine-made mainly in China, Korea, and Japan. There is a large difference in quality between needles from different manufacturers. In order to provide a standard manufacturing guideline, it seems necessary to make a Korean Industrial standard (KS). The authors review this topic from an historical view point, investigate the current situation of the standardization of acupuncture needles in other developed countries, and inspect the general procedure to establish a KS in Korea in order to suggest a KS for acupuncture needles.

• The Bulletin of The Korean Astronomical Society
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• v.42 no.2
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• pp.54.2-54.2
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• 2017

While quasars are sparse in number density, they reside at relatively high-redshift as compared to e.g. luminous red galaxies. Hence, they are likely to be less non-linearly evolved than the galaxy population, and thus have a distribution that more closely mirrors the primordial density field. Therefore, they offer an intriguing opportunity to search for Baryonic Acoustic Oscillations (BAO). To this end, the 3-point correlation function (3PCF) is an excellent statistical tool to detect BAO. In this work, we will make the first-ever measurement of the large-scale quasar 3PCF from the SDSS-IV DR14 quasar sample (spanning the largest volume to-date). This work will use the order N2-time 3PCF algorithmof Slepian & Eisenstein (2015), with N the number of objects.

• The Bulletin of The Korean Astronomical Society
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• v.42 no.1
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• pp.53.3-53.3
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• 2017

While quasars are sparse in number density, they reside at relatively high-redshift as compared to galaxies. Hence, they are likely to be less non-linearly evolved than the galaxy population, and thus have a distribution that more closely mirrors the primordial density field. Therefore, they offer an intriguing opportunity to search for primordial non-Gaussianity (PNG). To this end, the 3-point correlation function (3PCF) is an excellent statistical tool to detect departures from Gaussianity, vanishing for a Gaussian field. In this work, we will make the first-ever measurement of the large-scale quasar 3PCF from the SDSS-IV DR14 quasar sample (spanning the largest volume to-date) to place constraints on PNG through the usual f_NL-type parametrization. This work will use the order N^2-time 3PCF algorithm of Slepian & Eisenstein (2015), with N the number of objects.

• Molecules and Cells
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• v.38 no.5
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• pp.381-389
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• 2015

Autophagy is a lysosome-dependent intracellular degradation process that allows recycling of cytoplasmic constituents into bioenergetic and biosynthetic materials for maintenance of homeostasis. Since the function of autophagy is particularly important in various stress conditions, perturbation of autophagy can lead to cellular dysfunction and diseases. Accumulation of abnormal protein aggregates, a common cause of neurodegenerative diseases, can be reduced through autophagic degradation. Recent studies have revealed defects in autophagy in most cases of neurodegenerative disorders. Moreover, deregulated excessive autophagy can also cause neurodegeneration. Thus, healthy activation of autophagy is essential for therapeutic approaches in neurodegenerative diseases and many autophagy-regulating compounds are under development for therapeutic purposes. This review describes the overall role of autophagy in neurodegeneration, focusing on various therapeutic strategies for modulating specific stages of autophagy and on the current status of drug development.

• Molecules and Cells
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• v.22 no.2
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• pp.228-232
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• 2006

The Drosophila protein, Rbp9, is homologous to human Hu, which is reported to be involved in small cell lung cancer. Rbp9 functions in cystocyte differentiation, and mutations in Rbp9 cause ovarian tumors. Here we show that the antimicrobial peptide, Attacin, is upregulated in Rbp9 mutants, especially in ovaries where tumors form. Upregulation seems to result from activation of the NF-${\kappa}B$ pathway since we detected nuclear localization of Relish in Rbp9 mutant ovaries but not in wild type ovaries. Inactivation of NF-${\kappa}B$ in the Rbp9 mutant allows prolonged survival of malformed egg chambers. We conclude that Drosophila initiates an anti-tumor defense response via activation of NF-${\kappa}B$.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2005.04a
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• pp.273-276
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• 2005

본 논문은 고유얼굴 방법을 이용한 얼굴인식 시스템의 성능을 분석하였다. 제안한 고유얼굴을 이용한 얼굴인식 방법은 훈련집합의 얼굴 이미지 사이의 중요한 변화를 가지고 있는 특징공간으로 투영시키면서 이루어진다. 중요한 특징들은 얼굴집합의 고유벡터(주성분)들이기 때문에 고유얼굴이라 한다. 특징 공간으로의 투영은 고유얼굴의 가중치의 합으로 입력얼굴을 기술할 수 있으며, 입력 얼굴의 인식은 훈련집합의 가중치와 입력 영상의 가중치를 비교하면서 이루어진다. 본 논문에서는 제안된 방법의 검증을 위해서 Harvard 데이터베이스를 이용하였으며, 시스템의 성능 분석을 위하여 조명에 대한 인식성능의 변화, 사용한 고유얼굴의 수에 대한 인식률의 변화, 전처리를 통하여 얻을 수 있는 인식률의 변화, 인식 거부 곡선을 통하여 시스템의 적용 가능성에 대한 실험을 수행하여 분석한다.

• The Bulletin of The Korean Astronomical Society
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• v.45 no.1
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• pp.57.2-57.2
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• 2020

We observed the Class I protostar TMC-1A in polarized dust emission at 1.3 mm at a spatial resolution of ~40 au using ALMA. Previous observations revealed a disk (r~100 au), surrounded by an infalling envelope, and a CO outflow going in the north-south direction in TMC-1A. Our observations detected polarized dust emission in a central region (r~50 au) and ~100 au north and south of the central protostar. The former polarization is likely due to self-scattering because of the polarization direction along the disk minor axis, the polarization fraction independent of Stokes I, and a high optical thickness. The latter polarization is roughly in the outflow region. The position and direction, particularly in the north, imply multiple possible mechanisms: magnetically or mechanically aligned dust grains in the outflow or in an accretion flow.

• Korean Journal of Microbiology
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• v.48 no.3
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• pp.212-215
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• 2012

The antimicrobial activity of ursolic acid (UA) and oleanolic acid (OA), both triterpenoid compounds, against methicillin-resistant Staphylococcus aureus (MRSA) is controversial. We examined the antimicrobial effects of UA and OA against 19 strains of MRSA isolated from Koreans by determining minimum inhibitory concentrations (MIC) and minimum bactericidal concentrations (MBC). The data showed that the methicillin-sensitive strain S. aureus KCTC $1621^T$ was more resistant to UA and OA than that of the MRSA strains. The MBC values of UA and OA against MRSA had broad ranges; 4 to 32 ${\mu}g/ml$ and 16 to >256 ${\mu}g/ml$, respectively. It was difficult to understand the different antimicrobial activities of UA and OA among the MRSA strains, because UA and OA antimicrobial mechanisms are unknown. These results indicate that the antimicrobial effects of UA and OA against MRSA are dependent on resistance to UA and OA in each strain.