• International Journal of Industrial Entomology and Biomaterials
• /
• 제2권1호
• /
• pp.79-81
• /
• 2001

A study was conducted to establish the degree of genetic divergence between different hybrid forms and rearing conditions through estimation of the minimum number of genes (allelic pairs) differentiating parents in terms of specific quantitative traits. It was established that the minimum gene numbers differentiating parental lines in the inheritance of cocoon was 1, of cocoon shell weight- between 1 and 2, and of silk filament length- between 2 and 3. The variability in the specific genetic parameter could be explained by the reliability of the statistical-and-genetic method used and the expression of genes affecting the formation of each of the characters tested. Gene expression, in its turns is conditioned both by the gene interaction within the genotypes and the different genotype response to environmental change. To go deep in the problem, experiments should be conducted under strictly controlled conditions, reducing the mathematical-and-genetic analysis to a physiological levels and hence to analyse the genetic nature of the specific quantitative character formation and its genetic control.

• Communications for Statistical Applications and Methods
• /
• 제19권1호
• /
• pp.147-155
• /
• 2012

We propose some properties for a fuzzy correlation test by reduced-spread fuzzy variance for sample fuzzy data. First, we define the condition of fuzzy data for repeatedly observed data or that which includes error term data. By using the average of spreads for fuzzy numbers, we reduce the spread of fuzzy variance and define the agreement index for the degree of acceptance and rejection. Given a non-normal random fuzzy sample, we have bivariate normal distribution by apply Box-Cox power fuzzy transformation and test the fuzzy correlation for independence between the variables provided by the agreement index.

• 한국물환경학회지
• /
• 제24권2호
• /
• pp.214-220
• /
• 2008

Nitrifying bacteria were detected by fluorescent in situ hybridization (FISH) method at 6 sampling sites with different eutrophication degree in the Nak-Dong River and their tributaries. And conventional physico-chemical parameters including $NH_4-N$, $NO_3-N$, and TN were determined concurrently. In rainy period (July), there was no noticeable difference between the number of ammonia/nitrite-oxidizing bacteria detected at each site except Sang-Ju and the ratio of nitrifying bacteria to total counts stained by DAPI varied in 6~33%. By contrast, in the dry period (October), both of bacterial population was increased differently and the ratio of nitrifying bacteria to total counts ranged more widely from 6% in heavily polluted water zone, Hwa-Won to 60% in upper tributary with high agricultural land use. Byung-Sung-Chun. In January, the numbers of ammonia-oxidizing bacteria was reduced up to one tenth, while those of nitrite-oxidizing bacteria was apparently increased maybe due to high DO and low DOC.

• Journal of Plant Biology
• /
• 제23권3_4호
• /
• pp.69-83
• /
• 1980

Distribution of the naturalized plants in Korea was studied, based on the references reported by many authors from 1895 to 1980 and on the data obtained by survey of the present authors on 200 localities, 170 overpopulated areas and 30 islands in various size, in South Korea. We could describe 110 species in 27 families, including the pre-1945 records in North Korea. In this paper 14 naturalized species were newly described. Naturalized plants were characterized by dominated annual and hemigeophytes, 75.5% and 17.3%, respectively, in Raunkiaer's life form spectrum. The authors proposed two indices, i.e., Relative Naturalized Degree (RND) and Urbanization Index (UI). Increasing UI values or numbers of the naturalized plants in various localities were showed the correlation to the urbanized degree or population size in their localities.

• 대한수학회보
• /
• 제53권1호
• /
• pp.1-20
• /
• 2016

The general number field sieve (GNFS) is asymptotically the fastest known factoring algorithm. One of the most important steps of GNFS is to select a good polynomial pair. A standard way of polynomial selection (being used in factoring RSA challenge numbers) is to select a nonlinear polynomial for algebraic sieving and a linear polynomial for rational sieving. There is another method called a nonlinear method which selects two polynomials of the same degree greater than one. In this paper, we generalize Montgomery's method [12] using geometric progression (GP) (mod N) to construct a pair of nonlinear polynomials. We also introduce GP of length d + k with $1{\leq}k{\leq}d-1$ and show that we can construct polynomials of degree d having common root (mod N), where the number of such polynomials and the size of the coefficients can be precisely determined.

• 대한수학회논문집
• /
• 제28권3호
• /
• pp.425-432
• /
• 2013

Let S be a minimal surface of general type with $p_g(S)=q(S)=0$ having an involution ${\sigma}$ over the field of complex numbers. It is well known that if the bicanonical map ${\varphi}$ of S is composed with ${\sigma}$, then the minimal resolution W of the quotient $S/{\sigma}$ is rational or birational to an Enriques surface. In this paper we prove that the surface W of S with $K^2_S=5,6,7,8$ having an involution ${\sigma}$ with which the bicanonical map ${\varphi}$ of S is composed is rational. This result applies in part to surfaces S with $K^2_S=5$ for which ${\varphi}$ has degree 4 and is composed with an involution ${\sigma}$. Also we list the examples available in the literature for the given $K^2_S$ and the degree of ${\varphi}$.

• 한국항해항만학회지
• /
• 제44권2호
• /
• pp.73-78
• /
• 2020

The cruise industry in the Mediterranean region increased from 2000-2018, being the second most important region after the Caribbean. The purpose of this study was to analyze the networks and hub ports of the Mediterranean. This paper used the SNA (Social Network Analysis) methodology, which includes Hub and Authority Combined Centrality (HACC) that has been used to analyze cruise port centrality, as well as degree centrality such as In-Degree, Out-Degree, and Betweenness. This empirical study suggests that the top three ports of the Mediterranean ports' network in terms of hub index are Barcelona, Civitavecchia, and Palma de Mallorca. The academic implications are the suggestion for data integration based on real itineraries and numbers of POC (Port of Calls), as well as the selection of the hubs of the targeted areas. The practical implications are suggested such as a clear requirement for cruise industry, as a way to widen the scope for the Mediterranean region and a valuable reference for cruise ship companies to select the best fit home ports.

• International Journal of Fluid Machinery and Systems
• /
• 제10권1호
• /
• pp.76-85
• /
• 2017

Wall pressure measurements and flow visualization were conducted for a 90 degree elbow with an axis curvature radius the same as its inner diameter (125 mm). Reynolds numbers 320,000 and 500,000, based on the inner diameter and bulk velocity, were examined. A deflected inflow, having an almost constant velocity slope and a faster velocity at the inside, was introduced. Ensemble averaged pressure distributions showed that no difference of normalized pressure could be found in both the Reynolds number cases. Power spectral density functions of pressures exhibited that the fluctuation having the Strouhal number (based on the inner diameter and bulk velocity) of 0.6 existed in the downstream region of the elbow, which was 0.1 larger than that of the uniform inflow case [1]. Results of numerical calculations qualitatively coincided with the experimental ones.

• 가족자원경영과 정책
• /
• 제8권2호
• /
• pp.15-26
• /
• 2004

This research evaluated counseling tasks performed by consumer counselors between Korea and Japan. Results of this research could be summarized as follows. First, not only female but also male counselors occupied counseling tasks in Korea, in Japan, all counselors were female, most of whom were married and older than in Korea. The average number of counselors in Korea was large than those in Japan, but income of counselors was higher in Japan. Average numbers of counseling were large, the level of perception on the significance of counseling tasks was lower in Korea, but degree of job satisfaction was higher in Korea than their Japanese counterparts. Second, evaluation scores of Korean counselors were higher than those in their Japanese counterparts in the light of objectiveness and fairness of counseling. On the other hand, the degree of job satisfaction among counselors and their perceptions on the significance of counseling tasks affected the evaluation scores. In contrast, both degree of job satisfaction and hours of job-training education generated those impacts. finally, Korean counselors highly evaluated their agencies' counseling tasks than their Japanese counterparts. In sum, this study showed that the overall performance of consumer counseling tasks was more positive in Korea than in Japan.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 1994년도 추계학술대회 논문집 학회본부
• /
• pp.261-263
• /
• 1994

This paper deals with the on off arc characteristics of electromagnetic relay contacts contaminated by NaCl and $H_2SO_4$. In this paper, I have studied the characteristics of on-off voltage waveform. the contact errosion, contact surface analysis by SEM and EDAX under changed R-L parameter of testing circuit. After considers these result, I have tried to promote the diagnosis method and developed the contacts. As a results, (1) The arc duration and the numbers of arc occurrence characteristics are depended on contamination degree. The contamination degree is high when the arc characteristics is high. (2) Under clean condition, arc occurrence voltage, surge peak voltage, arc duration and the rate of contact errosion is lower than wet condition. (3) Surge peak voltage and arc duration is depended on L parameter. When L is High, the arc characteristics is high.