• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2002년도 하계학술대회 논문집 A
• /
• pp.320-326
• /
• 2002

Distribution system loss minimization re-configuration is 0-1 planning problem, and the number of combinations requiring searches is extremely large when dealing with typical system scales. For this reason, the application of a genetic algorithm (GA) seems attactive to solve this problem. Although Genetic algorithms are a type of random number search method, they incorporate a multi-point search feature and are therefore superior to one-point search techniques. The efficiency of GAs for solving large combinational problem has received wide attention. Further, parallel searching can be performed and the optimal solution is more easily reached. In this paper, for improving GA convergence characteristics in the distribution system loss minimization re-configeration problem, a chromosome "Limited Life" concept is intro duced. Briefly, considering the population homogenization and genetic drift problems, natural selection is achieved by providing this new concept, in addition to natural selection by fitness. This is possible because individuals in a population have an age value. Simulations were carried out using a model system to check this method's validity.

• 한국멀티미디어학회논문지
• /
• 제10권9호
• /
• pp.1185-1196
• /
• 2007

게임산업의 경쟁력을 강화하고 부가가치를 높이기 위하여 수요자가 요구하는 높은 만족도를 갖는 게임을 개발할 수 있도록 만족도를 정량적으로 평가하여 만족도 기준을 제시할 수 있는 연구 및 근거가 필요하다. 특히 만족도 요소들의 점수화와 모집단 분포의 추정은 중요한 과제로서 이를 통하여 어떤 게임이 다른 게임에 비하여 만족도가 높은지 낮은지를 알 수 있으며 만족도를 제고시키기 위하여 보완해야 할 요소들과 기술력을 예측할 수 있다. 본 연구에서는 게임 만족도 요소들의 접수분포를 정규화 하는 방법을 제 안하고 시뮬레이션을 통한 모수적 밀도함수 추정방법을 이용하여 모집단 분포를 추정하였다.

• 지역사회간호학회지
• /
• 제29권4호
• /
• pp.414-428
• /
• 2018

Purpose: The purpose of this study is to identify the spatial distribution of hypertension prevalence and to investigate individual and regional-level factors contributing to the prevalence of hypertension in the region. Methods: This study is a cross-sectional research using the 2015 Community Health Survey. Total 64,473 people from 7 metropolitan cities were used for the final analysis. Geoda program was adopted to identify the regional distribution of hypertension prevalence and analyzed by descriptive statistics, one-way ANOVA and correlation analysis using SPSS statistics 23.0 program. Multi-level analysis was performed using SPSS (GLMM). Results: The prevalence of hypertension was related to individual level factors such as age, monthly household income, normal salt intake, walking practice days, and regional level factors including number of doctors per 10,000 population, number of parks, and fast food score. Besides, regional level factors were associated with hypertension prevalencies independently without the effects of individual level factors even though the influences of individual level factors ware larger than those of regional factors. Conclusion: Respectively, both individual and regional level factors should be considered in hypertension intervention programs. Also, a national level research is further required by exploring various environmental factors and those influences relating to the hypertension prevalence.

• 한국환경과학회지
• /
• 제33권4호
• /
• pp.235-247
• /
• 2024

A total of 64 individuals of Acanthogobius flavimanus, which inhabit the coast of Korea, were collected from 8 regions from July to August 2023. A haplotype network and a phylogenetic tree were created. The genomic DNA of the target fish species was compared and analyzed with the genomic DNA of four regions in Japan downloaded from the National Center for Biotechnology Information (NCBI). In the haplotype network of Acanthogoboius flavimanus, Eocheong-do (EC) and Goseong (MAJ) exhibited low genetic similarity with other regions in Korea and Japan. The Phylogenetic tree showed that the population of MAJ exhibited differences in genetic structure compared to populations in other regions of Korea and Japan, indicating a distant relationship. Most marine organisms are known to migrate and spread via ocean currents, which is the most crucial factor promoting gene flow through larvae between populations. The haplotype of Acanthogobius flavimanus in MAJ differs from the haplotypes in Korea and Japan. The population in MAJ is believed to have limited genetic exchange due to the North Korea Cold Currents. We identified haplotype patterns based on the geographical distribution of Acanthogobius flavimanus off the coast of Korea and inferred that ocean currents have some influence on genetic distances.

• The Plant Pathology Journal
• /
• 제26권3호
• /
• pp.238-244
• /
• 2010

Spatial and temporal distribution of Bacillus licheniformis N1 was investigated over time on the leaves, petioles and crowns of the strawberry plants. Bacterial population on the strawberry plants was quantified over time by selective plating. Bacterial population of N1 containing a plasmid pWH43G carrying green fluorescent protein (GFP) declined relatively faster on the plant surface as compared to the Strain N1 itself. However, this result was found to be enough to utilize the strain to visualize bacterial colonization on the plant surface. When B. licheniformis N1 was treated together with Silwet L-77 at 0.03%, the bacterial population on plant surface persisted for up to 7 days. B. licheniformis N1 (pWH43G) containing Silwet L-77 was applied on the strawberry plants and the GFP expressing bacteria were visualized by confocal laser scanning microscopy. Bacterial persistence was also investigated in a growth chamber and in a plastic house after N1 bioformulation treatment on the strawberry plant. The Strain N1 colonized three different tissues well and persisted over 3 to 5 days on the strawberry plants. They formed bacterial aggregates on plant surfaces for at least 3 days, resulting in a biofilm to resist fluctuating plant surface environment. However, the bacterial persistence dramatically declined after 7 days in all tested tissues in a plastic house. This study suggest that B. licheniformis N1 colonizes the strawberry plant surface and persists for a long time in a controlled growth chamber, while it can not persist over 7 days on the plant surface in a plastic house.

• 한국환경과학회지
• /
• 제18권10호
• /
• pp.1163-1170
• /
• 2009

The clam, Gomphina melanaegis, which is commonly called the sandy beach clam because of its habitat, is a valuable organism in the sandy coast of East Sea, Korea. It is frequently observed in large populations between 0.5 and 5 meters. We have released 50,000 seedling, ranging from the diameter of approximately 3 mm, 2007, and 1,000,000 seedling, ranging from the diameter of approximately 0.2 mm, plus 100,000 adult individuals, ranging from the shell length of approximately 20~40 mm, 2008 at Jinha beach. The spawning period of G. melanaegis, was from June to August, and the main spawning occurred in July. This investigation was carried out to elucidate population distribution on the stocking area of sandy beach clam, G. melanaegis. The relationship between shell length and ring radius in each ring was investigated as a regression line. The relationship between the shell length and shell height of released young clam was SH=1.0105SL-4.7764 ($R^2=0.7905$). The relationship between the shell length and total weight of released young clam was $TW=0.0013SL^{2.3966}$($R^2=0.71$). It draws a deduction that the ring of this clam was produced once a year during the duration between June and August.

• The Korean Journal of Ecology
• /
• 제21권1호
• /
• pp.27-33
• /
• 1998

Arisaema robustum, which has the ability to change sex, was studied in a temperate broadleaf forest of Sanseong-ri, Joongbu-myeon, Gwangju-gun, Kyonggi Province, Korea. \ulcornerThe study, carried out from 1993 to 1997, focused on population dynamics energy budget among organs, size distribution, mortality, the relationships between sex and size, seed production and germination rate. In terms of energy budget among the organs, the ratio of aboveground to belowground biomass was 36.6 : 63.4 in non-female plants, and 81.4 : 18.6 in female plants. Also, in female plants, the ration of leaf to sexual organ biomass was 39.5 : 41.9. Therefore, the belowground ratio of female plants was lower than that of non-female plants. Plants were classified into 8 levels relative to the amount of leaf area by $100cm^2$. The rates of the smallest and the largest classes were 49% and 1%, respectively, and population distribution by size was relatively stable. The mortality averaged 13.1% per year and decreased in inverse proportion to leaf size (6.6% in the smallest and 0.0% in the largest size classes). Leaf areas were $64.1{\pm}48.5cm^2$ in non-flowering plants, $232.1{\pm}123.9cm^2$ in males and $444.8{\pm}153.9cm^2$ in females. The increase rates of leaf area per year varied from 1.9% in plants changing from female tomale, to 152.4% in plants changing from non-flowering to female. But plants which remained female for 2 years showed a decrease of 34.7%. >From this result, it is thought that the female plants invest more energy to reproduction than to vegetative organs. The correlation coefficient (CC) value between plant size and the number of seeds produced (0.55) was larger than the CC value between plant size and total seed weight (0.73). That is, the larger the plant size, the heavier the seed produced. The germination rate increased along with seed weight, and it was 95% in plants which were over 60mg fresh weight/seed.

• Imaging Science in Dentistry
• /
• 제52권1호
• /
• pp.75-82
• /
• 2022

Purpose: This cross-sectional study evaluated and categorized the tomographic sagittal root position (SRP) of the maxillary anterior teeth in a Brazilian population. Materials and Methods: Cone-beam computed tomographic scans of 420 maxillary anterior teeth of 70 patients (35 men and 35 women, mean age 25.2±5.9 years) were evaluated. The SRP was classified as class I, II, III, or IV. In class I, the root is positioned against the buccal cortical plate; in class II, the root is centered in the middle of the alveolar housing; in class III, the root is positioned against the palatal cortical plate; and in class IV, at least two-thirds of the root engage both the buccal and palatal cortical plates. Results: In total, 274 teeth (65.2%) were class I, 39 (9.3%) were class II, 3 (0.7%) were class III, and 104 (24.8%) were class IV. The frequency distribution over the teeth groups was different from the overall analysis. Important differences were found in the frequencies of classes I, II, and IV compared to other populations. Sex was not associated with the SRP classes (P=0.307). Age distribution was significantly different over the classes (P=0.004). Conclusion: The findings of this study on the distribution of SRP classes among the Brazilian population compared to other populations demonstrate that the SRP should be analyzed on a case-by-case basis for an accurate treatment plan in the maxillary anterior area.

• The Korean Journal of Ecology
• /
• 제21권5_2호
• /
• pp.491-499
• /
• 1998

An investigation was performed to establish the mathematical theories of a vibration for the plant growth and a wave distribution of a plant population on the boundary condition of a limiting factor in the environment. The mathematical theories of the plant growth vibration and wave distribution had been elucidated by the plant growth and the timber line on the middle slope of the west side of Mt. Paektu. The Betula ermaruii composes the timber line on about 2,060 m elevation of sea label, has a growth vibration on the ground surface and takes a wave distribution due to a boundary condition of alpine temperature gradient.

• Asian-Australasian Journal of Animal Sciences
• /
• 제25권7호
• /
• pp.935-944
• /
• 2012

Amur grayling, Thymallus grubii, is an important economic cold freshwater fish originally found in the Amur basin. Currently, suffering from loss of habitat and shrinking population size, T. grubii is restricted to the mountain river branches of the Amur basin. In order to assess the genetic diversity, population genetic structure and infer the evolutionary history within the species, we analysised the whole mitochondrial DNA control region (CR) of 95 individuals from 10 rivers in China, as well as 12 individuals from Ingoda/Onon and Bureya River throughout its distribution area. A total of 64 variable sites were observed and 45 haplotypes were identified excluding sites with gaps/missing data. Phylogenetic analysis was able to confidently predict two subclade topologies well supported by maximum-parsimony and Bayesian methods. However, basal branching patterns cannot be unambiguously estimated. Haplotypes from the mitochondrial clades displayed local homogeneity, implying a strong population structure within T. grubii. Analysis of molecular variance detected significant differences among the different geographical rivers, suggesting that T. grubii in each river should be managed and conserved separately.