• Proceedings of the Korea Water Resources Association Conference
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• 2016.05a
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• pp.158-158
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• 2016

본 연구에서는 극치 분포의 오른쪽 꼬리 부분 예측 시 안정적인 확률수문량 산정하는 확률분포형과 매개변수 추정 방법을 평가하기 위해 Monte Carlo 모의를 수행하였다. 수문자료의 빈도해석에 적합한 것으로 알려진 generalized extreme value (GEV), Gumbel (GUM), generalized logistic (GLO), gamma3 (GAM3), normal (NOR), log-normal3 (LN3) 총 6개의 확률분포형을 바탕으로 오른쪽 꼬리 부분의 확률수문량 추정 성능을 모의 실험을 통해 평가하고자 한다. 30년 이상 자료를 보유한 기상청 지점의 지속기간별 연최대값 자료를 분석한 결과를 바탕으로 모분포를 GEV분포로 선정하였으며 평균이 1.0, 표준편차 0.5, 왜곡도 계수는 0.5, 1.0, 2.0, 3.0, 4.0이 되도록 가정하였다. 또한 자료 길이에 따른 성능 평가를 위해 표본 크기 20, 50, 100, 150, 200개에 대해 분석을 수행하였다. 위와 같은 가정으로 총 25종류(왜곡도계수 5개 ${\times}$ 표본 크기 5개)의 발생된 모분포에 6가지의 확률분포형과 3가지의 매개변수 추정방법(모멘트법, 최우도법, 확률가중모멘트법)을 조합한 18가지의 모델을 비교 분석해보았다. 평가방법으로는 평균 제곱근 오차(Root Mean Square Error, RMSE), 편의(bias), 평균 상대오차(Mean Relative Difference, MRD), 평균 절대 상대오차(Mean Absolute Relative Difference, MARD)를 사용하여 적용 모델의 성능을 비교 분석하였다.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.32 no.2
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• pp.201-207
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• 1987

This experiment was conducted to identify the superior corn hybrids for silage production and to determine the combining ability of their parental inbred lines. A 7-entry diallel cross was evaluated for grain and stover yields, and agronomic characters under 3 different seasons. Hybrids Hi34 x Tx601, Hi26 x Hi34, and Hi29 x Hi34 showed high total dry matter yields. In general, late maturing hybrids had higher grain and silage yields than early maturing hybrids. Leaf area index was correlated with grain and stover yields. Rust rating was negatively correlated with yields and all characters, indicating that rust (Puccinia sorghi) was one of the major factors affecting yields. Diallel analysis showed that inbred Hi34 which was late in maturity and resistant to rust was the best combiner for both grain and silage yields. General combining ability (GCA) and specific com-bining ability (SCA) effects for yields and other characters were significant, suggesting that both additive and non-additive gene effects are involved for those characters. Ratio of GCA/SCA mean squares showed that GCA effects were more important than SCA effects for yields and other characters. GCA x season and SCA x season interactions were significant for grain and stover yields, revealing that gene effects were not stable for those yields under dissimilar environments.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.28 no.1
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• pp.39-46
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• 2015

The purpose of this study is to analyze the deflection of the prestressed beams. In this paper, a finite element model for deflections of prestressed beams is presented. Proposed finite element model was verified comparing with existing experimental results, and it showed a good agreement with the experimental results. Also, a parametric study has been conducted to analyze the influence of eccentricity, span-depth ratio, and prestressing force. The finite element model results were compared with hand calculation results. Deflections were increased as the eccentricity decreases, the span-depth ratio increases, and the prestressing force decreases. Hand calculation overestimated the deflection when the eccectricity or prestressing force is too small.

• The Journal of the Acoustical Society of Korea
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• v.32 no.1
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• pp.32-42
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• 2013

Typical underwater piezoelectric spherical sensors are omni-directional, thus can measure the scalar quantity sound-pressure-magnitude only with the limitation not being able to measure the direction of the incoming wave. This paper proposes a method to simultaneously measure both the magnitude and direction of the sound wave with the spherical sensor. The method divides the piezoceramic sphere of the sensor into eight elements, and distinguishes the magnitude and direction of the sound pressure by combining the output voltage of the elements in a particular manner. Further, through the analysis of the sensitivity variation in relation to the structural parameters like radius and thickness of the piezoceramic sphere, we have suggested the way to improve the sensitivity of the vector sensor.

• Parasites, Hosts and Diseases
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• v.31 no.3
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• pp.285-292
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• 1993

C. sinensis total RMh was containing large amount of 185 rRNA but little 285 rRNA. The size of the double-stranded cDNA synthesized from poly $(A)^{+}$ mRNA was 0.4-4.2 kb long with tapering unto 9.5 kb. Degenerated oligonucleotides (as 2 sense and 3 antisense Primers) were designed on the conserved regions of the known tropomyosin amino acid sequences. From one out of the PCR amplifications using total CDNA and matrix of primers, a specific gene product, 580 bp in size, was produced. Upon Southern hybridization of the PCR products with Schistosomn mnnsoni tropomyosin (SMTM) CDNA, only one signal appeared at the band of 580 bp product. This 580 bp product was considered to encode C. sinensis tropomyosin (CSTM) and cloned in pGEM-3Zf(-) for DNA sequencing. CSTM cDNA was 575 bp containing one open reading frame of 191 predicted amino acids, which revealed 86.3% homology with SMTM and 51.1% with rrichostronsylur coeubnlormis tropomyosin. CSTM cDNA obtained will serve as a probe in the studies of molecular cloning of CSTM.

• Korean Journal of Microbiology
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• v.39 no.2
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• pp.118-122
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• 2003

To develop vector plasmid for the bacteriophage P2-P4 system which is a useful experimental tool for the study of viral capsid assembly, we constructed a new P4-derived vector plasmid starting from P4 ash8 sid71 With recombinant DNA technology, a portion of P4 genome was deleted and tetracyclin resistance gene (terR) was introduced into P4 genome to give P4 selectivity. Resulting P4 ash8(sid71) terR was 12.09 kb long and could be converted to a viable bacteriophage with P2 infection. The burst size of induced bacteriophage form of P4 ash8(sid71) terR was determined. The CsCl buoyant equilibrium density gradient experiment of new P4 derivative suggested the upper limit of packaging capacity in P2-size head.

• Journal of the Korea Society of Computer and Information
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• v.11 no.6 s.44
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• pp.99-106
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• 2006

Type classification is a very needed step in recognizing huge character set language such as korean characters. Since most previous researches are based on the composition rule of Korean characters, it has been difficult to correctly classify composite vowel characters and problem space was not divided equally for the lack of classification of last consonant which is relatively bigger than other graphemes. In this paper, I Propose a new type classification method in which horizontal vowel is extracted before vortical vowel and last consonants are further classified into one of five small groups based on horizontal projection profile. The new method uses 19 character types which is more stable than previous 6 types or 15 types. Through experiments on 1.000 frequently used character sets and 30.614 characters scanned from several magazines, I showed that the proposed method is more useful classifying Korean characters of huge set.

• Korean Chemical Engineering Research
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• v.56 no.3
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• pp.404-409
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• 2018

The integration of organic and inorganic building blocks into hierarchical porous architectures makes potentially desirable catalytic material in many catalytic applications due to their combination of dissimilar components and well-constructed reactant transport path. In this study, we prepared the hierarchical porous $Co_3O_4@graphene$ 3D gel by hydrothermal method to achieve high catalytic performance in PET glycolysis reaction. Obtained $Co_3O_4@graphene$ 3D gel consisted of interconnected networks of $Co_3O_4$ and graphene sheets, providing large number of accessible active sites for efficient catalytic reaction. These structural merits from synergistic effect of $Co_3O_4$ and graphene gave a high performance in the PET degradation reaction giving high conversion yield of BHET, fast degradation rate of PET, and remarkable stability.

• Journal of the Korean Institute of Telematics and Electronics S
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• v.35S no.8
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• pp.47-54
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• 1998

With the increasing popularity of the use of large-volume image database in various application, it becomes imperative to build an efficient and fast retrieval system to browse through the entire database. We present a new method for a content-based image retrieval by using a variable block size and block matching algorithm. Proposed approach is reflecting image features that exploit visual cues such as color and space allocation of image and is getting the fast retrieval time by automatical convergence of retrieval times which adapt to wanting similarity value. We have implemented this technique and tested it for a database of approximately 150 images. The test shows that a 1.9 times fast retrieval time compare to J & V algorithm at the image retrieval efficiency 0.65 and that a 1.83 times fast retrieval time compare to predefined fixed block size.

• Microbiology and Biotechnology Letters
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• v.17 no.5
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• pp.447-453
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• 1989

In order to study the transfer of antibiotics resistance genes of the genetically cloned bacteria in water environments, DK1 strain, which is resistant to kanamycin (Km), chloramphenicol (Cm), streptomycin (Sm), and sulfadiazine (Su), was selected from the Gram-negative bacterial isolates from wastewater. One of 4 plasmids harboured in the DK1 strain was found to possess Km$^{${\gamma}$}$Cm$^{${\gamma}$}$ gene and be about 68 kb in size, and it was designated as pDK101. The plasmid of pDK101 was also found to have 16, 32, and 6 restriction sites for EcoRI. .PstI, and SalI, respectively. From the digestion fragments of pDK101 plasmid and pKT230 used as a vector by EcoRI restriction endonuclease, pDT309 and pDT529 were constructed as chimeric plasmids which possess Km$^{${\gamma}$}$Cm$^{${\gamma}$}$ gene and are 30.9 and 52.9 kb in size, respectively. When the chimeric plasmids were trasformed into E. coli C600 or E. coli HB101, transformants of DKC601, DKC602, DKH102, and DKH103 were obtained as cloned bacterial cells. The Km$^{${\gamma}$}$Cm$^{${\gamma}$}$ genes were well expressed in those cloned cells and the chimeric plasmids were clearly detected in the cloned cells of DKC601 and DKH103.