• Journal of the Korea Society of Computer and Information
• /
• v.20 no.3
• /
• pp.69-74
• /
• 2015

This paper offers solutions to unresolved $43{\leq}R(5,5){\leq}49$ and $102{\leq}R(6,6){\leq}165$ problems of Ramsey's number. The Ramsey's number R(s,t) of a complete graph $k_n$ dictates that n-1 number of incidental edges of a arbitrary vertex ${\upsilon}$ is dichotomized into two colors: (n-1)/2=R and (n-1)/2=B. Therefore, if one introduces the concept of distance to the vertex ${\upsilon}$, one may construct a partite graph $K_n=K_L+{\upsilon}+K_R$, to satisfy (n-1)/2=R of {$K_L,{\upsilon}$} and (n-1)/2=B of {${\upsilon},K_R$}. Subsequently, given that $K_L$ forms the color R of $K_{s-1)$, $K_S$ is attainable. Likewise, given that $K_R$ forms the color B of $K_{t-1}$, $K_t$ is obtained. By following the above-mentioned steps, $R(s,t)=K_n$ was obtained, satisfying necessary and sufficient conditions where, for $K_L$ and $K_R$, the maximum distance should be even and incidental edges of all vertices should be equal are satisfied. This paper accordingly proves R(5,5)=43 and R(6,6)=91.

• Journal of the Korea Society of Computer and Information
• /
• v.19 no.5
• /
• pp.19-25
• /
• 2014

In this paper, I seek the chromatic number, the maximum number of colors necessary when adjoining vertices in the plane separated apart at the distance of 1 shall receive distinct colors. The upper limit of the chromatic number has been widely accepted as $4{\leq}{\chi}(G){\leq}7$ to which Hadwiger-Nelson proposed ${\chi}(G){\leq}7$ and Soifer ${\chi}(G){\leq}9$ I firstly propose an algorithm that obtains the minimum necessary chromatic number and show that ${\chi}(G)=3$ is attainable by determining the chromatic number for Hadwiger-Nelson's hexagonal graph. The proposed algorithm obtains a chromatic number of ${\chi}(G)=4$ assuming a Hadwiger-Nelson's hexagonal graph of 12 adjoining vertices, and again ${\chi}(G)=4$ for Soifer's square graph of 8 adjoining vertices. assert. Based on the results as such that this algorithm suggests the maximum chromatic number of a planar graph is ${\chi}(G)=4$ using simple assigned rule of polynomial time complexity to color for a vertex with minimum degree.

• JSTS:Journal of Semiconductor Technology and Science
• /
• v.14 no.4
• /
• pp.376-382
• /
• 2014

In this paper, a 9-bit 1GS/s high precision folding A/D converter with a 45 nm CMOS technology is proposed. In order to improve the asymmetrical boundary condition error of a conventional folding ADC, a novel scheme with an odd number of folding blocks is proposed. Further, a new digital encoding technique is described to implement the odd number of folding technique. The proposed ADC employs a digital error correction circuit to minimize device mismatch and external noise. The chip has been fabricated with 1.1V 45nm Samsung CMOS technology. The effective chip area is $2.99mm^2$ and the power dissipation is about 120 mW. The measured result of SNDR is 45.35 dB, when the input frequency is 150 MHz at the sampling frequency of 1 GHz. The measured INL is within +7 LSB/-3 LSB and DNL is within +1.5 LSB/-1 LSB.

• International Journal of Advanced Culture Technology
• /
• v.8 no.2
• /
• pp.1-5
• /
• 2020

As the world gradually advances to an aging society, the quality of human life is valued. Among them, 'quality of sleep' is very closely related to quality of life. Recently, Korea expanded health insurance coverage for "sleep disorders". Particularly, as the number of sleep multiple tests and prescriptions for sleep aids has increased rapidly, much attention has been focused on the related medical service environment. Therefore, this study looked at an in-depth interview of 11 hospitals to see what treatment delivery system is being established when the government applies health insurance for 'sleep disorders'. In conclusion, the organizations with the most average number of sleep polyp tests per day were found to have more sleep polyp labs (hardware) and more full-time specialists. Also, the polysomnography lab (hardware) and the specialist's full-time status (software) did not necessarily result in a "positive pressure regulator prescription" that can solve "sleep apnea" caused by "sleep ailments". Rather, it was found that the number of days of sleep multiple laboratories (hardware), the number of full-time specialists (software) or the specialty majors (software) had a greater impact. In particular, the higher the specialist's full-time personnel (software) index (=6.000), the higher the sleep-inducing agent prescription rate(=1.000), and the lower the specialist's full-time personnel (software) index (=1.000), the higher the sleep-inducer's prescription rate(= 0.010) Was low. In addition, even if the professional full-time personnel(software) index was the same (=1.000), the hospital type was lower as it was closer to the public hospital(=0.067) and higher at the specialized hospital (= 0.933). In the case of university hospitals, when the full-time specialists (software) are in the same condition (= 1.000), the frequency of use of the sleep laboratory (=1.000) and the sleep test rate (= 1.000) were all the same.

• The Korean Journal of Food And Nutrition
• /
• v.11 no.5
• /
• pp.499-505
• /
• 1998

The purpose of this study was to ivestigate the structural characteristics of waste soulble browning reaction prodcuts (WS-BRPs) isolated from Korean red ginseng. They all showed the maximum absorbances at near 280 nm. Their IR spectra suggested the presence of hydroxyl, amide carbonyl and aliphatic methine groups. From sugar analysis it was identified that L and S-1 contained two kinds of suggar, glucose and xylose, and S-2, a fructose together with glucose and xylose. Thirteen different amino acids were identified in L. Ten amino acids from S-1 and seven amino acids from S-2 were identified using Auto Amino Acid Analyzer. Glycine, serine and glutamic acid in S-1 and one unknown amino acid and glycine in S-2 were detected as the major amino acids, respectively. From the 1H-and 13C-NMR spectra, it was identified that a number of sugar moieties, carbonyl and carbon double bonds (only in S-2) were contained in the three WS-BRP components. Approximate number of sugar moiety of L, S-1 and S-2 was determined to be 8∼10, 9∼11 and 4∼5, respectively. Contents of nitrogen, carbon and hydrogen showed L>S-1>S-2.

• Research in Community and Public Health Nursing
• /
• v.28 no.1
• /
• pp.1-12
• /
• 2017

Purpose: The purpose of this study is to examine factors affecting quality of life among grandparents raising their grandchildren. Methods: This study carried out a secondary analysis of data from the 2014 Korean Longitudinal Study of Aging (KLoSA) and Statistics Korea. Data collected from 224 grandparents who reported raising their grandchildren were analyzed using descriptive statistics, independent t-test, ANOVA, pearson correlation coefficient, and multilevel regression analysis. Results: The mean score of the participants' quality of life was 62.63. Significant predictors of quality of life of the grandparents included subjective health status, last year's total house income, number of last year's travels, frequency of last year's movie seeing, and number of children's parks per 100,000 population. Conclusion: These results suggest that public health nurses in improving quality of life of grandparents focus on children's parks and formal social supports as community factors as well as regular exercise as an individual factor in order to be more effective.

• Journal of Gastric Cancer
• /
• v.15 no.1
• /
• pp.19-28
• /
• 2015

Purpose: To compare the clinicopathological data and long-term survival of gastric cancer patients in China and Korea. Materials and Methods: Patients who had undergone gastrectomy for gastric cancer between 1998 and 2009 in 2 high-volume institutions in both China (n=1,637) and Korea (n=2,231) were retrospectively evaluated. Clinicopathological variables, overall survival (OS), progression-free survival (PFS), and surgery-related complications were assessed for all patients and compared between the 2 institutions. Results: Chinese patients included in the study were significantly older and had a significantly lower body mass index (BMI) than the Korean patients. Esophagogastric junction tumors were more frequent in Chinese patients. However, the number of patients with stage I gastric cancer, the number of harvested lymph nodes, and the number of total gastrectomies were significantly higher in the Korean population. Korean patients also presented with fewer undifferentiated tumors than Chinese patients. Furthermore, Korean patients had prolonged OS and PFS for stage III cancers only. BMI, tumor-node-metastasis (TNM) stage, tumor invasion, number of positive lymph nodes, and distant metastases were all independent factors affecting OS and PFS. Conclusions: Although China and Korea are neighboring Asian countries, the clinicopathological characteristics of Chinese patients are significantly different from those of Korean patients. Korean gastric cancer patients had longer OS and PFS than Chinese patients. Influencing factors included TNM stage, tumor invasion, and lymph node metastasis.

• Asia Marketing Journal
• /
• v.15 no.3
• /
• pp.97-115
• /
• 2013

This paper was motivated by two gaps in the extant literature on brand portfolio planning. First, research has shown that, as the number of products connected to a brand increases, the extended product receives more favorable evaluations. However, this result was obtained by comparing two brands with different number of products while controlling the brands' breadths. Hence one may question if the above result would hold when the brand is narrow as well as broad. Second, the literature has investigated the effect of brand breadth on the perceived fit and evaluations of an extended product within a relatively limited range ("narrow vs. broad") and not considered the case of a "very broad" brand. To address these gaps, we propose two hypotheses: 1) the effects of the number of products associated with a brand on the perceived fit and evaluations of a moderately far brand extension are moderated by the brand's breadth (H1); and 2) the relationship between a brand's breadth and a moderately far extension's perceived fit and evaluations looks like an inverse-U shape (H2). Study 1 was conducted to test H1. Study 1 employed a 2 × 2 within-subjects design in which the first factor was the number of products (small (2) or large (5)), and the second factor was brand breadth (narrow or broad). We measured brand breadth as the perceived similarity among products associated with a brand. Participants provided the perceived fit and evaluations of an extended product. Study 2 was conducted to test H2 as well as to replicate Study 1 in a more general setting and with different products. It employed a 2 × 3 within-subjects design, in which the first factor was the number of products (small (2) or large (5)), and the second factor was brand breadth (narrow, broad, or very broad). The results from two experiments support both hypotheses. This paper contributes to the literature on brand extensions in two ways. First, it broadens our understanding of the effects of product number and brand breadth on extended product evaluations by considering the two factors jointly. Second, we believe this study to be the first to present evidence that brand breadth can exert an inverted U-shape effect on the perceived fit and evaluations of an extended product. The results also offer implications for marketers. First, marketers should heed the finding that adding similar products to a narrow brand does not help the brand's extension launch. Second, the finding that the relationship between brand breadth and extended product evaluations might not be linear provides practical implications. While a narrow brand should not keep launching close extensions, nor should a broad brand continue producing far extensions to broaden its breadth. A firm with a broad corporate or family brand might want to consider introducing a new brand instead of adding dissimilar products under the brand umbrella.

• Korean System Dynamics Review
• /
• v.14 no.1
• /
• pp.69-87
• /
• 2013

The purpose of this paper is to explore the relationship between the number of relocation and volition of soldier's service based on system thinking perspective using a causal loop analysis. Research adopting system dynamics concerning on the volition of soldier's service and relocation has not been studied yet. Causal loops are analyzed and evaluated by focusing on soldier's military performance, stress of family members and family members' welfare service. Result of this study is that soldier's periodical movement is indispensable factor maintaining military life. Most of the married soldier's life conditions are worse than ordinary people. As the number of relocation is increasing family of soldier's stress is increased by anxiety for welfare conditions is supposed to relocate. The number of movement to another place of soldier's children is more than two times and the result of learning achievement is worse than ordinary students. This kind of stress can influence the married soldier's military performance and stress. So the welfare service should be expanded to an official residence, education, facility, district network service and so on.

• Korean Journal of Child Studies
• /
• v.25 no.1
• /
• pp.1-12
• /
• 2004

This study investigated the relations of children's age, intelligence, and the concept of conservation to their learning of English. Ten 4-year-old children from 1 child-care center and 13 7-year-old children from 1 elementary school were tested after completion of 8 sessions of experimental English classes. Children's intelligence was measured by K-WPPSI for 4-year olds and K-WISC for 7-year-olds. Children were tested for number and liquid conservations. A Korean teacher with 11 years of experience of teaching children at American elementary schools taught the 2 groups with the same subjects and methods. Data were analysed by independent samples t-test, Mann-Whitney U test, and Pearson's r. The results showed that children's age and the concept of conservation were related to English learning. No statistically significant relationship with IQ was found.