• Journal of Computing Science and Engineering
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• 제7권2호
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• pp.99-111
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• 2013

Approximating a divergence between two probability distributions from their samples is a fundamental challenge in statistics, information theory, and machine learning. A divergence approximator can be used for various purposes, such as two-sample homogeneity testing, change-point detection, and class-balance estimation. Furthermore, an approximator of a divergence between the joint distribution and the product of marginals can be used for independence testing, which has a wide range of applications, including feature selection and extraction, clustering, object matching, independent component analysis, and causal direction estimation. In this paper, we review recent advances in divergence approximation. Our emphasis is that directly approximating the divergence without estimating probability distributions is more sensible than a naive two-step approach of first estimating probability distributions and then approximating the divergence. Furthermore, despite the overwhelming popularity of the Kullback-Leibler divergence as a divergence measure, we argue that alternatives such as the Pearson divergence, the relative Pearson divergence, and the $L^2$-distance are more useful in practice because of their computationally efficient approximability, high numerical stability, and superior robustness against outliers.

• Journal of Microbiology and Biotechnology
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• 제8권6호
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• pp.560-567
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• 1998

We have found that Thermoactinomyces vulgaris KFB-Cl00 produces a chitinase. The optimum temperature and pH of the enzyme activity were $55^{\circ}C$ and 6.5. The enzyme was stable after heat treatment at $80^{\circ}C$ for 30 min and stable in acidic and basic conditions (PH 6.0~11.0). The thermostable endo-chitinase from Thermoactinomyces vulgaris KFB-C100 was cloned into the plasmid pBR322 by using E. coli DH5$\alpha$ as a host strain. The positive clone carrying a recombinant plasmid (PKCHI23) with a 4.1-kb fragment containing the chitinase gene was found. The recombinant plasmid was analyzed to determine the essential region for chitinase activity and obtained a 2.3-kb fragment, which was sub cloned into pTrc99A using the PstI and SalI sites to construct pTrc99A/pKCHI23-3. The resulting plasmid exerted high chitinase activity upon transformation of E. coli XL1-Blue cells. Chitinase was overproduced 14 times more in the clone cells than in the wild-type cells and the enzyme was purified to homogeneity. The purified enzyme showed the similar properties as the native chitinase from T. vulgaris in terms of molecular weight and substrate specificity. The catalytic action of the cloned enzyme was an endo type, producing chitobiose as a major reaction product.

• Journal of Microbiology and Biotechnology
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• 제14권3호
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• pp.474-482
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• 2004

The $\alpha$-L-arabinofuranosidase (Arfase) gene of Bacillus stearothermophilus No. 236 was cloned and sequenced. The ORF of the gene, designated arfA, encoded a 507 -residue polypeptide with calculated molecular mass of 57 kDa. The Arfase produced by a recombinant Escherichia coli strain containing the arfA gene was purified to apparent homogeneity and characterized. The molecular mass of the Arfase determined by SDS-PAGE was 60 kDa. However, according to gel filtration, it was estimated to be approximately 190 kDa. These results indicated that the functional form of the Arfase is trimeric. The optimal pH and temperature for the enzyme activity were pH 6.5 and $55^{\circ}C$, respectively. The half-life of the enzyme at $60^{\circ}C$ was about 6 h. Kinetic experiments at $45^{\circ}C$ with pNPM (p-nitrophenyl $\alpha$-L-arabinofuranoside) as a substrate gave the $K_m and V_{max}$ values of 1.19 mM and 26.1 U/ mg, respectively. When the enzyme was combined with Bacillus stearothermophilus No. 236 endoxylanase and $\beta$-xylosidase, it hydrolyzed arabinoxylan into L-arabinose and xylose more efficiently than Arfase alone. This synergistic effect suggested that the complete hydrolysis of xylan with large amounts of arabinose side chains required Arfase as well as endoxylanase and $\beta$-xylosidase.

• 대한물리치료과학회지
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• 제7권2호
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• pp.459-474
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• 2000

The purpose of this study is to identify the posture correction program as the development of the posture maintenance performance, and search for the more efficient posture correction program. The data analysis was processed by SPSS. The data was analysed with $x^2$-test, t-test, pearson product moment correlation, and stepwise regression analysis. The finding of this study is as follows: There are the homogeneity between two groups was verified on the know ledges CF=.697, df=2, P>.05), self-efficacy(F=.098, df=2, P>.05) about the posture. The developed posture correction program has proved to enhance the posture maintenance performance(knowledge t=1.60, P<.05 ; posture manintenance t=7.69, P<.01). The type of posture correction program showed some significant differences (t=5.62, P<.01) in the accuracy of movement way among the factors of the posture maintenance performance. The posture maintenance performance affected self-efficacy. Therefore, the major conclusion is as follows: The posture correction program was meaningfully effective on developing the posture maintenance, and with practice created accuracy much more on the posture maintenance movement way. The development of the posture maintenance performance affected the increase of self-efficacy about the posture. The self-efficacy has proved so powerful factor to influence on the posture maintenance performance development. So, the posture correction program should be done systematically and continually, and developing the posture maintenance performance should be done with practice. After the education, it should be reinforced through practice, midterm identification and reeducation and motivated with recognizing the accurate posture measurement. And it should be created the correction program to develop the high self-efficacy about the posture. It needs the strategy to educate the correct posture individually, and to spread to the society for healthy life style.

• Journal of Microbiology and Biotechnology
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• 제1권3호
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• pp.188-196
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• 1991

The ${\beta}-glucosidase$ was purified to homogeneity from the culture filtrate of P. verruculosum by column chromatography. The enzyme was a glycoprotein with a relative size of approximately 220 kDa with an isoelectric point of 4.8, which was composed of dimeric protein of 105 kDa. The enzyme was stable up to $60^{\circ}C$ and the presence of glycerol significantly increased its thermostability. The enzyme was found to hydrolyze both ${\beta}-aryl$ and ${\beta}-alkyl-glucosides$ in addition to ${\beta}-glucosyl$ glucose and catalyzed glucosyl transfer to cellobiose. The enzyme attacked laminarin in an exotype-like fashion. The apparent Km's of the enzyme toward cellobiose, laminaribiose, laminarin were 0.53 mM, 0.35 mM and 1.11 mM, respectively. Glucose and glucono-${\delta}-lactone$ were competitive inhibitors for the enzyme. Copper ($Cu^{2+}$), mercury ($Hg^{2+}$) and p-chloromercuribenzoate were strong inhibitors of the enzyme. The immunoblotting result revealed that one form of ${\beta}-glucosidase$ was biosynthesized, irrespective of carbon sources used. Polyacrylamide gel electrophoresis analysis of the in vitro translated product of total RNA from avicel grown mycelium established that the P. verruculosum ${\beta}-glucosidase$ precursor was approximately 95 kDa in size. The amino acid composition and N-terminal amino acid sequence are given.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2008년도 추계학술대회 논문집 Vol.21
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• pp.429-429
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• 2008

Li$[Ni_{1/2}Co_{1/2}]O_2$ powder were synthesized from co-precipitation spherical metal oxide, $[Ni_{1/2}Co_{1/2}](OH)_2$. The preparation of metal hydroxide was significantly dependent on synthetic conditions, such as pH, amount of chelating agent, stirring speed, etc. The optimized condition resulted in $[Ni_{1/2}Co_{1/2}](OH)_2$, of which the particle size distribution was uniform and the particle shape was spherical, as observed by scanning electron microscopy. Calcination of the uniform metal hydroxide with LiOH at higher temperature led to a well-ordered layer-structured Li$[Ni_{1/2}Co_{1/2}]O_2$, as confirmed by X-ray diffraction pattern. Also these materials have ${\alpha}-NaFeO_2$ ($R\bar{3}m$) structure. Due to the homogeneity of the metal hydroxide, $[Ni_{1/2}Co_{1/2}](OH)_2$, the final product, Li$[Ni_{1/2}Co_{1/2}]O_2$, was also significantly uniform, i.e., the average particle size was of about 10 to 15 ${\mu}m$ in diameter and the distribution was relatively narrow. As a result, the corresponding tap-density was also high approximately 2.41 $gcm^{-3}$, of which the value is comparable to that of commercialized $LiCoO_2$.

• 대한화학회지
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• 제33권1호
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• pp.65-69
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• 1989

방사성 바륨 또는 방사성 란탄 추적자를 함유하고 있는 Ba(NO$_3)_2$ 와 TiO(NO$-3)_2$의 무기혼합용액을 옥살산의 에탄올 용액으로 적정하므로써 바륨티탄닐의 옥살산 염을 합성하였고, 이를 1000$^{\circ}$C에서 하소시켜 BaTiO$_3$를 만들었다. 옥살산염의 분석결과는 BaTiO(C$_2O_4)_2{\cdot}4H_2O$이며, 무기혼합용액중 Ba/Ti의 몰비가 0.950∼1.05 범위 내에서 화학양론적 결합으로 합성됨을 방사성 바륨 추적자의 도움으로 쉽게 확인하였고, Perovskite형의 구조임을 XRD로 확인하였다. 그리고 란탄 첨가제가 침전에 화학적으로 균일하게 혼입됨은 방사성 란탄의 추적자 실험으로 발견하였다. 이와 같은 실험적 사실로부터 침전물의 구성 성분의 결합이 분자준위에서 일어나고 또 티탄산바륨이 단일상의 결정임을 설명하였다.

• Journal of Microbiology and Biotechnology
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• 제18권7호
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• pp.1235-1244
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• 2008

Indole-3-acetic acid (IAA) is produced commonly by plants and many bacteria, however, little is known about the genetic basis involving the key enzymes of IAA biosynthetic pathways from Bacillus spp. IAA intermediates from the Gram-positive spore-forming bacterium Paenibacillus polymyxa E681 were investigated, which showed the existence of only an indole-3-pyruvic acid (IPA) pathway for IAA biosynthesis from the bacterium. Four open reading frames (ORFs) encoding indole-3-pyruvate decarboxylase-like proteins and putative indole-3-pyruvate decarboxylase (IPDC), a key enzyme in the IPA synthetic pathway, were found on the genome sequence database of P. polymyxa and cloned in Escherichia coli DH5$\alpha$. One of the ORFs, PP2_01257, was assigned as probable indole-3-pyruvate decarboxylase. The ORF consisted of 1,743 nucleotides encoding 581 amino acids with a deduced molecular mass of 63,380 Da. Alignment studies of the deduced amino acid sequence of the ORF with known IPDC sequences revealed conservation of several amino acids in PP2_01257, essential for substrate and cofactor binding. Recombinant protein, gene product of the ORF PP2_01257 from P. polymyxa E681, was expressed in E. coli BL21 (DE3) as a glutathione S-transferase (GST)-fusion protein and purified to homogeneity using affinity chromatography. The molecular mass of the purified enzyme showed about 63 kDa, corresponding closely to the expected molecular mass of IPDC. The indole-3-pyruvate decarboxylase activity of the recombinant protein, detected by HPLC, using IPA substrate in the enzyme reaction confirmed the identity and functionality of the enzyme IPDC from the E681 strain.

• 농약과학회지
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• 제16권4호
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• pp.350-356
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• 2012

숙련도시험 수행 및 분석법확립은 분석기관의 지속적인 시험결과에 대한 신뢰성 확보 및 시험기관의 분석능력 관리를 위한 정도관리 체계에 포함되는 항목이다. Emamectin benzoate 및 lufenuron 유제 시료에 대한 분석법 검증, 안정성 및 균질성을 확인한 후, 농약 이화학시험 분석기관(33개 기관)을 대상으로 두 약제에 대한 시료를 배포하여 숙련도시험을 수행하였으며, 분석기관의 수행능력을 z값으로 평가하였다. Emamectin benzoate는 참여기관 총 33개 중 이상값은 2개 기관(6.0%), z값이 |Z| > 3.0 및 |Z| < -3.0 범위을 나타내는 부적합은 2개 기관(6.0%) 및 z값이 -2.0 < |Z| -3.0 및 2.0 < |Z| < 3.0 범위인 검토대상은 3기관(9.0%)이었고, lufenuron에 대한 z값의 범위가 검토대상인 기관은 3개(9.0%)였다. 본 연구는 국내 농약 이화학시험 분석기관에 적합한 정도관리 체계 마련을 위하여 숙련도 시험의 적용가능성을 확인하였으며, 추가적으로 다양한 농약제품에 대한 숙련도시험을 수행하여 보완이 필요하다.

• 디자인학연구
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• 제17권3호
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• pp.413-420
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• 2004

웹사이트의 특성에 따라 요구되는 감성을 파악하고 이를 디자인에 반영할 수 있는 새로운 디자인 방법론이 요구되고 있다. 기존의 사용성 위주의 웹 디자인 방법과는 차별화 되는 이와 같은 감성 연구를 통한 디자인 방법은 웹 디자이너들에게 또 다른 유용한 지침을 제공할 것이다. 하지만 이제까지 이에 관한 연구가 충분히 이루어지지 않아 특정 감성을 유발하는 웹 디자인을 위해 디자이너들은 자신의 직감과 경험에 의존할 수밖에 없었다. 이와 같이 특정 감성을 유발하는 디자인 방법론의 개발을 위해 본 연구에서는 감성공학에서 사용되는 감성 어휘를 이용한 감성공학 1류(Nagamachi, 2002, 박경수, 2000) 방법을 웹 디자인에 적용하여 특정 감성을 사용자에게 전달하는 방법을 알아보았다. 연구를 위해서 감성을 잘 전달할 수 있는 136개의 웹사이트를 전문 웹 디자이너들의 추천을 통해 우선적으로 선정하고 실험에 사용한 감성어휘(최재호, 2001)들을 잘 나타낼 수 있다고 판단되는 22개의 웹사이트를 최종적으로 선정하여 설문조사를 통해 감성 평가를 실시하였다. 표본 웹사이트들은 디자인 요소의 활용 정도, 균형, 전체 비중, 균일성 등을 고려하여 정량적으로 다시 평가하였다. 정량적 평가와 감성평가 결과 사이의 인과관계는 회귀분석을 통해 살펴보았고 그 결과를 바탕으로 특정 감성을 유발하는 웹 디자인 방법론을 제시하였다. 본 연구에서 사용된 방법과 절차는 감성유발과 관련된 디자인방법론 개발을 위해 다른 연구에서도 적용될 수 있을 것이며 회귀분석을 통한 디자인 방법론은 실제로 웹 디자인에 활용될 수 있을 것이다.논하였다. 본 연구는 웹에서의 사용자 경험에 대한 관점을 정황적 요소로까지 확장하고 이를 체계적으로 매핑하는 실증적인 사례를 제시함으로써 웹에서의 혁신적이며 크로스 사이트, 크로스 장르적인 컨텐츠 플래닝의 가능성을 시사하는데 의의가 있다고 하겠다.y used to some of interactive storytelling through hyper text in CD-ROM and web sites. More complicated and different structured models were born through games that offered graphics, virtual spaces and interactivity. When drawn onto a structural graph, few attributes and similarities seem to occur. This paper will try to outline and discuss structural graphs of interactive storytelling methods and suggest some ways for better storytelling design.eal sales volume, but the case study could verified that this method is effective to the evaluation of marketability in case of completely new product got on the typical category and the product category could