• Journal of Microbiology
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• 제34권4호
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• pp.300-304
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• 1996

To define the effects of zooplankton and phytoplankton to bacteria, bacterial numbers, frequency of dividing cells (FDC) and size distribution were performed with image analysis in the surface layer of Lake Soyang. In August 1992, when Anabaena was blooming, the bacterial number increased at daytime. Bacterial numbers and FDC value had a negative correlation (r = 0.83, P < 0.01). Bacterial size spectrums were dynamically changed during the day and night, especially the small bacteria less than $0.5\;{\mu}m^3$. Meanwhile, in October, after the bloom, the bacterial number was only one third of that in August, even though the FDC was higher than that in August. The bacterial numbers of small size class dropped at 13:00. But the size spectrums were relatively constant during the night time. These results suggest that the bacterial growth was tightly coupled with phytoplankton during Anabaena bloom. And after the bloom, the bacterial number was controlled grazing activity of zooplankton at daytime.

• Kyungpook Mathematical Journal
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• 제64권1호
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• pp.133-159
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• 2024

In a previous work we studied generalized Stirling numbers of the second kind S^{(a₂,b₂,p₂)}_a1,b1 (p₁, k), where a₁, a₂, b₁, b₂ are given complex numbers, a₁, a₂ ≠ 0, and p₁, p₂ are non-negative integers given. In this work we use these generalized Stirling numbers to define Bernoulli polynomials in two variables B_p1,p2 (x₁, x₂), and Euler polynomials in two variables E_p1p2 (x₁, x₂). By using results for S^{(1,x₂,p₂)}_1,x1 (p₁, k), we obtain generalizations, to the bivariate case, of some well-known properties from the standard case, as addition formulas, difference equations and sums of powers. We obtain some identities for bivariate Bernoulli and Euler polynomials, and some generalizations, to the bivariate case, of several known identities for Bernoulli and Euler numbers and polynomials of the standard case.

• 복식
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• 제50권7호
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• pp.113-127
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• 2000

The purpose of this study was to examine the symbolic meaning of oriental numbers based on Yin-Yang(陰陽) theory. Based on the thought of Yin-Yang Wu-Hsing(陰陽五行), the number was divided the number of the heaven (positive number) 1, 3. 5, 7, 9 from the number cf the earth(negative number) 2. 4, 6, 8, 10. It was descrived very well in the dress and its ornaments and the folk customs. In the costume of the Court, there were 9, 7, 5, 3 patterns costume for the king and queen. Even though an even number, 12 patterns costume for the emperor symbolized 12 months and made it of the principal of the universe. Korean traditional costume Han-bock(韓服) was formed with the three dimentional principal of circle (圓.$\bigcirc$), square(方.$\square$) and triangularity(角.$\Delta$). In the middle of odd numbers, number 3 was regarded as a holy number of the heaven (天), the earth(地) and a man(人). Taken for a highest number. number 3 had the symbolism of wishes for good fortune. Number 10 and number 100, which meant the fullness and the long life, were used regularly. With Ten longevity patterns(十長生紋), the feast of a hundred-day-old baby, our race prayed for the healthy long life. As mentioned above. the symbolism of the number though the costume prefered the positive number to the negative one. Accommodating to the universal principal and the cycle. The deep meaning and the symbolism of the number has been implied the mental wishes.

• 기술혁신학회지
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• 제14권3호
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• pp.466-487
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• 2011

본 연구에서는 중소기업의 연구개발 집중도 및 특허가 주가수익률에 미치는 영향에 대해 분석하였다. 코스닥 상장기업 중 제조업을 대상으로 최근 10년('00~'09)간의 표본을 이용하여 상관관계 분석 및 희귀분석한 결과는 다음과 같이 요약할 수 있다. 첫째, 연구개발 집중도와 주가수익률과는 음(-)의 관계가 존재함을 확인하였으나 국내특허출원건수 및 국내특허등록건수와는 유의한 관계를 발견하지 못했다. 둘째, 연구개발 집중도가 주기수익률에 미치는 영향에 관한 분석결과, 연구개발 집중도는 주가수익률에 1% 수준에서 음(-)의 관계가 존재하는 것으로 나타났다. 셋째, 국내특허출원건수 및 국내특허등록건수가 주가수익률에 미치는 영향에 관한 분석결과, 국내특허출원건수 및 국내특허등록건수는 주가수익률과의 관계에서 유의한 관계를 발견하지 못했다. 넷째, 고기술 산업은 연구개발 집중도가 주가수익률에 1% 수준에서 음(-)의 관계가 존재하는 것으로 나타났으며, 국내특허출원건수와는 1% 수준에서 정(+)의 관계가 존재하는 것으로 나타났다. 중고기술 산업 및 중저기술 산업에서는 연구개발 집중도가 주가수익률에 1% 수준에서 음(-)의 관계가 존재하는 것으로 나타났으나, 국내특허출원건수 및 국내특허등록건수와의 관계에서는 유의한 관계를 발견하지 못했다. 이러한 연구결과는 연구개발투자 및 특허가 기업성과로 이어지기 위해서는 기업별로 기술수준을 고려한 기술혁신 전략이 필요함을 시사한다.

• 대한기계학회논문집B
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• 제35권12호
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• pp.1335-1341
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• 2011

본 연구의 목적은 평행 평판과 경사진 평판의 물질전달 특성을 비교하여 경사각에 따른 유동의 박리와 재부착이 물질전달에 미치는 영향을 규명하는 것이다. 나프탈렌승화법을 사용하여 평판에서의 국소물질전달계수를 측정하였으며, 평판의 경사각은 $10^{\circ}$에서 $-10^{\circ}$까지 $5^{\circ}$간격으로 변화시키고 유동 속도는 2m/s에서 15m/s까지 변화시켰다. 양의 각으로 경사진 평판에서 국소 Sherwood 수는 경계층이 발달하면서 감소하는 경향을 보이고 있는며, 음의 각으로 경사진 평판의 경우는 재순환 와류의 박리점에서 최소값을 나타내고, 박리된 유동의 재부착점에서 최대값을 나타내었다. 평균 Sherwood 수는 음의 각과 양의 각 모두 평행 평판보다 낮았다.

• 한국수산과학회지
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• 제45권5호
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• pp.445-453
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• 2012

This study examined microbial contamination during seasoned and dried squid Dosidicus gigas processing, including the apparatus, machines, and employee's gloves at each step in processing at two companies. The numbers of bacteria floating in air in each processing area were also examined. The numbers of Staphylococcus aureus (3.6-6.0 log CFU/g) and Escherichia coli (1.3-1.4 log MPN/100 g) in domestic and imported daruma (a semi-processed product of seasoned and dried squid) at companies A and B exceeded the regulatory limits of the Food Sanitary Law of Korea (S. aureus, ${\leq}2.0$ log CFU/g; E. coli, negative). S. aureus in both daruma was reduced to below the detection limit or 3.6 log CFU/g after the roasting step, but increased again to 3.3 and 5.5 log CFU/g after the mechanical tearing step at companies A and B, respectively. E. coli showed similar tendencies at both companies. The surfaces of the apparatus, machines, and employee's gloves that contacted daruma were also contaminated with S. aureus (1.0-5.5 log CFU/$m^2$) and E. coli (negative-to 3.5 log MPN/$m^2$). The numbers of bacteria floating in air were high (1.7-5.1 log CFU/$m^3$) at both companies. These results suggest that sanitation standard operating procedures (SSOP) must be developed to control of microbial cintamination in seasoned and dried squid.

• 한국가축번식학회지
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• 제12권1호
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• pp.37-41
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• 1988

These studies were carried out to examine the sex of preimplantation mouse embryo. For the investigation of sex-ration of mouse embryos, morula and blastocysts stage embryos treated with H-Y antiserum (10%, v/v) and FITC anti-mouse-IgG were divided into the positive and negative embryos. Positive and negative identified embryos were observed the viability according to the in vitro cultured and the sex ratio was also investigated by chromosomal analysis. The results obtained in these studies were summarized as follows: 1. Two hundred sixty-seven recovered embryos of morula or blastocyst stage were incubated in medium containing H-Y antiserum and FITC anti-mouse-IgG. Positively or negatively identified embryos were 139 and 128. This trend indicated the approximal sex ratio was 1:1. 2. Sex ratio was measured using the embryos treated with indirect immunofluorescence assay to examine the relationship between embryo developmental stage and sex ratio. Sex ratio of morula stage embryos was 45.2% positive and 54.8% negative, on the other hand, the ratio switched to 56.4% positive and 43.6% negative embryo in blastocyst stage. 3. Fourty-seven positive and 57 negative embryos were obtained out of 104 morula stage embryos treated with indirect immunofluorescence assay. Survived positive or negative embryos during in vitro culture were 42 and 49, respectively out of 47 and 57 embryos. 4. The numbers of negative and positive embryos were 171 and 92 out of 163 blastocyst embryos which were incubated in the medium containing H-Y antiserum and FITC anti-mouse-IgG. The result of karyotype test showed the successful rate of sexing embryo is positive and negative embryos was63.0% (58/92) and 62.0% (44/71). The final female to male ratio within 58 positive embryos was 22.7:77.6, and the ratio of the 44 negative embryos was 77.3:22.7.

• 한국자원식물학회지
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• 제14권3호
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• pp.183-187
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• 2001

남부지방에 적합한 품종의 효율적인 선발을 위한 기초자료를 얻고자 9품종을 공시하여 생육 및 수량조사, 유전분산, 환경 분산, 유전력, 상관을 조사한 결과를 요약하면 다음과 같다. 1. 다수성이며 꽃대발생수가 적어서 품질이 우수한 Sunwol 택사 품종이 남부지방에 가장 적합한 품종으로 나타났었다. 2. Sunwol 품종의 모든 형질에 대한 유전력은 대부분의 형질에서 높았다. 3.형질 상호간의 상관에서 건근 수량은 초장, 엽수와는 정의상관으로 유의성이 높았고 꽃대 발생수, 묘상의 초장, 묘상의 엽수와는 부의상관으로 나타났다. 4. 건근 수량과 상관이 높았던 형질들은 유전력 추정에서도 높게 나타났다.

• Kyungpook Mathematical Journal
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• 제57권2호
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• pp.251-263
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• 2017

The aim of this paper is to investigate the dynamical behavior of the difference equation $$x_{n+1}={\frac{{\alpha}x_n}{{\beta}+{\gamma}x^p_{n-1}x^q_{n-2}}},\;n=0,1,{\ldots}$$, where the parameters ${\alpha}$, ${\beta}$, ${\gamma}$, p, q are non-negative numbers and the initial values $x_{-2}$, $x_{-1}$, $x_0$ are positive numbers. Also, some numerical examples are given to verify our theoretical results.

• 유체기계공업학회:학술대회논문집
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• 유체기계공업학회 2000년도 유체기계 연구개발 발표회 논문집
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• pp.193-199
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• 2000

The effects of Reynolds number on the non-nulling calibration of a cone-type five-hole probe in low-speed flows have been investigated at the Reynolds numbers of $2.04{\times}10^3,\;4.09{\times}10^3$, and $6.13{\times}10^3$. The calibration is conducted at the pitch and yaw angles in ranges between -35 degrees and 35 degrees with an angle interval of 5 degrees. The result shows that each calibration coefficient, in general, is a function of the pitch and yaw angles, so that the pre-existing calibration data in a nulling mode are not enough in accounting for the full non-nulling calibration characteristics. Due to the interference of the probe stem, the calibration coefficients have more Reynolds number sensitivity at positive pitch angles than at negative ones.