• Title/Summary/Keyword: significant cluster

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An Evaluation of the Coupling Coordination Degree of the Yangtze River Delta Port Cluster Based on Coupling Theory

  • Lu Ke;Yong-Sik Oh
    • Journal of Navigation and Port Research
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    • v.48 no.2
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    • pp.78-87
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    • 2024
  • To quantitatively assess the correlation between subsystems within a port cluster and the overall coordinated development of the port group, the current paper evaluates the coordinated development of port clusters. First, we construct an evaluation index system for the coupling and coordination of port clusters. Next, we introduce the contribution index of port subsystems, coupling degree, and coupling coordination degree functions to formulate a coupling coordination evaluation model for the port cluster. Finally, we use the Yangtze River Delta port cluster as a case study for validation, specifically using empirical data from 2012 to 2021. The findings reveal distinct phased characteristics in the coupling and coordination of port clusters in the Yangtze River Delta, marked by a notable transition from "maladjustment" to "coordination." Further, sustained high coupling values over a decade indicate a significant level of competition and cooperation among ports within the Yangtze River Delta port cluster. Over time, this competitive and collaborative dynamic has progressively evolved toward a more positive and structured direction. Lastly, it is expected that the evaluation model proposed in this paper can be extrapolated to other port clusters to gauge the extent of coordinated development, thereby facilitating horizontal comparisons and vertical analyses.

Improving TCP Performance Over Mobile ad hoc Networks by Exploiting Cluster-Label-based Routing for Backbone Networks

  • Li, Vitaly;Ha, Jae-Yeol;Oh, Hoon;Park, Hong-Seong
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.33 no.8B
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    • pp.689-698
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    • 2008
  • The performance of a TCP protocol on MANETs has been studied in a numerous researches. One of the significant reasons of TCP performance degradation on MANETs is inability to distinguish between packet losses due to congestion from those caused by nodes mobility and as consequence broken routes. This paper presents the Cluster-Label-based Routing (CLR) protocol that is an attempt to compensate source of TCP problems on MANETs - multi-hop mobile environment. By utilizing Cluster-Label-based mechanism for Backbone, the CLR is able to concentrate on detection and compensation of movement of a destination node. The proposed protocol provides better goodput and delay performance than standardized protocols especially in cases of large network size and/or high mobility rate.

A Study on the Presentation of Idea in Information and Entropy Theory in Vegetation Data (식피 Data 에 대한 Information 과 Entropy 이론의 실용연구)

  • Park, Seung Tai
    • The Korean Journal of Ecology
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    • v.10 no.2
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    • pp.91-107
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    • 1987
  • This study is concerned with some methods and applications, used as a basis on information and entropy analysis of vegetation data. These methods are adopted for the evaluating the effect of sampling intensity on information, which repersnets the departure of observed variable from standard component. Classes on the data matrix are caluculated by using marginal dispersion array for rank and weighting information program. Finally the information and entropy are computed by applying seven options. On the application of vegetation studies, two models for cluster analysis and analysis of concentration are explained in detail. Cluster analysis is based on use of equivocation information and Rajski's metrics. The analysis of concentration utilizes coherence coefficience being transformed values, which has been adjusted from blocks and entropy values. The relationship btween three begetation clusters and four stands of Naejangsan data is highly significant in 79% of total variance. Cluster A relatively tends to prefer north side, and cluster C south side.

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Importance of Clusters in Industry Development: A Case of Singapore's Petrochemical Industry

  • Pillai Jayarethanam
    • Journal of Technology Innovation
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    • v.14 no.2
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    • pp.1-27
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    • 2006
  • This paper rejuvenates the existing discussion on the importance of cluster approach to industry development strategies. Current evidences suggest that the shape of economic policy and practice is changing significantly around the world. Governments continually search for new tools and policy formulas to improve economic performance and create economic prosperity for all citizens. In this context a more proactive and strategic role for government in support of the cluster-based economic development model has emerged. This paper uses Singapore's petrochemical industry as an example to study the cluster approach to industry development. In doing so, there is much optimism to the importance of state and its institutions to play a significant role on industry development. Nevertheless, the study also raises doubts on whether the cluster-based strategy is due to the concept itself or due to other important factors.

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Weak Lensing Analysis On The Merging Galaxy Cluster Abell 115

  • Kim, Mincheol;Jee, Myungkook J.
    • The Bulletin of The Korean Astronomical Society
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    • v.42 no.1
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    • pp.51.1-51.1
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    • 2017
  • The galaxy cluster Abell 115 shows ongoing merger features, which suggest that it might be in an intermediate phase of dynamical evolution. As merging clusters often show, the characteristic hints of A115's merging activities include radio relics, double X-ray peaks, and large offsets between the cluster member galaxies and the X-ray distributions. To constrain the exact stage of the merger, it is necessary to obtain its dark matter distribution. In this study, we carry out a precision weak lensing study of this interesting system based on Subaru images. We present our mass reconstruction together with descriptions on our core procedure of the analysis: Subaru data reduction, galaxy shape measurement, and source selection. We find that Abell 115 consists of two massive dark matter clumps, which closely follow the cluster galaxies. Our weak lensing mass estimate is a few factors lower than the published dynamical mass obtained from velocity dispersion. This large mass discrepancy may be attributed to a significant departure from dynamical equilibrium.

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Construction of Highly Integrated PC Cluster based on Windows XP (높은 집적도를 가지는 Windows XP PC 클러스터 구축)

  • Lee S.-K.;Shin J.-R.;Choi J.-Y.
    • 한국전산유체공학회:학술대회논문집
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    • 2005.04a
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    • pp.41-46
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    • 2005
  • A new PC cluster was designed and constructed based on Windows XP Operating system. Primary target of the present design was the high node density per rack by using the general PC parts those are cost-effective and readily available in the market. Other major design points were system cooling and the convenient maintenance using standard PC parts. Presently 24 nodes per rack seems to be optimum considering the specification of the network switching device, system cooling and power supply, but 40 nodes can be accommodated within a single rack at maximum. Windows XP was selected as a high-performance computing environment considering the cost and the convenience in acquisition, maintenance and education. Both fast-Ethernet and Gigabit Ethernet network connection were tested and compared with previous data, especially for Linux doter using Myrinet. The result shows that there is no significant difference between the operating systems and the Fast-Ethernet and/or Gigabit Ethernet are good solution for the high-performance PC cluster considering the cost and performance.

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Effect of Thermal Conditions on the Cluster Formation of Sulfonated Polystyrene Ionomers

  • Kim, Hee-Seok;Kim, Joon-Seop;Jo, Byung-Wook
    • Bulletin of the Korean Chemical Society
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    • v.19 no.3
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    • pp.354-358
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    • 1998
  • The effect of thermal conditions on the clustering of sulfonated polystyrene ionomers was investigated. It was found that when the zinc-sulfonated ionomer was dried above a matrix glass transition temperature (Tg), the cluster Tg was observed at ca. 310 ℃, which is ca. 45 ℃ higher than that for the ionomer dried below the matrix Tg. This difference is believed to be the result of the increase in chain mobility at higher temperatures, which improves the multiplet formation and clustering; thus the cluster Tg increases. In the lithium ionomer case, however, the increase in the cluster Tg was ca. 6 ℃ upon annealing. From the results, it was suggested that in the zinc ionomer, the zinc ion is soft and divalent, which results in weaker interactions in multiplets, and thus decreases the stability of the multiplets. Therefore, the thermal effect is more significant for the zinc ionomers than for the lithium ionomers.

Effects of Single-Row Transplantation on Improving Strawberry Growth and Marketable Yield

  • Park, Gab-Soon;Kim, Young-Chil;Ann, Seoung-Won
    • Journal of Environmental Science International
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    • v.25 no.6
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    • pp.749-756
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    • 2016
  • This study shows how the growth of the top part of plants cultivated using the single-row strawberry method, with 12 cm plant spacing, as well as that of plants cultivated through conventional planting, is characterized by the presence of many leaves in the first flower cluster harvest. The leaf area and crown diameter were the largest in the 12 cm spacing method. The hight top fresh weight (59.2 g) was detected wen the 12 cm spacing method was used followed by conventional planting and, 9 cm and 6 cm spacing method. The K and Ca contents in the first flower cluster were the highest when the 12 cm spacing method (2.0% and 2.1%, respectively) and conventional planting, (0.42% and 0.86%, respectively) were used, and these values were significantly higher than the K and Ca contents obtained using the other two methods. The N, P, Mg, Fe, and B contents show no significant differences across the planting methods. The sugar content of the first flower cluster fruits was the highest when the 12 cm spacing method was used, while the sugar content of the fourth flower cluster fruits was highest after conventional planting. Firmness was the highest in the first, third, and fourth flower clusters after conventional planting, while no significant differences were observed for the 6 cm, 9 cm, and 12 cm spacing methods. A yield of 25 g or above during November to December was observed to be the highest when the 12 cm spacing method was used, while a yield of 10-16 g was the highest when both the 9 cm and 12 cm spacing methods werw used. The yield of products in January-April was the highest when the 12 cm spacing and conventional planting methods were used, and total product yield was also the highest for these methods. A significant portion of non-marketable products (39 g) was obtained when the conventional planting method was used.

The Purchase Behaviors of Luxury Goods in Internet Shopping Malls according to Shopping Orientation

  • Shin, Su-Yun;Jang, Eun-Young
    • The International Journal of Costume Culture
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    • v.9 no.2
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    • pp.113-124
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    • 2006
  • The purposes of this study were to investigate the perceived risks and the purchase behaviors for luxury goods in internet shopping malls according to the shopping orientation. 254 questionnaires were distributed from April 10 to May 9 in 2006. For data analysis, frequency, percentage, factor analysis, cluster analysis, chi-square tests were conducted. The results could be summarized as follows. (1) According to cluster analysis of shopping orientation, respondents were classified into five groups: pursuit of pleasure, pursuit of fashion, price consciousness, planned shopping, brand and store loyalty, time-saving and convenience. (2) There were not significant differences in the perceived risks according to shopping orientation. (3) There were not significant differences in purchase reasons and were significant differences in no-purchase reasons.

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The Differences of the Big Five Personality among Clusters of Children according to Interests to Living Things (생물에 대한 흥미에 따른 초등학생들의 군집 유형별 성격 5요인 차이)

  • Kim, Heung-Tae;Jeon, Min-Jeong;Kim, Jae Geun
    • Journal of Korean Elementary Science Education
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    • v.33 no.4
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    • pp.646-654
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    • 2014
  • The aim of this study was to investigate the patterns of the elementary school students' interests to animals and plants based on affinity toward animals and plants, and curiosity about animals and plants by using a cluster analysis. In addition, the differences of the big five personality traits by the identified clusters was examined. A total number of 411 elementary school students participated in the study. The students were clustered into four distinct interest groups with respect to the level of interests to animals and plants. Cluster 1 'Developed Interest to Organisms group' showed high levels in the interest to both animals and plants. Cluster 2 'Developed Interest to Animals group' showed high interest to animals and relatively low interest to plants whereas cluster 3 'Developed Interest to Plants group' showed high interest to plants and relatively low interest to animals. Lastly, cluster 4 were identified as 'Lack of Interest to Organisms group' by showing low levels of interest to both animals and plants. The four identified groups also showed different distributions of students according to gender and school year. These results support gender difference in the interest to animals and plants and suggest the decreased and specialized interest with school year. The Big Five personality traits excluding neuroticism were positively related with the interest to organisms and the identified groups showed significant differences in the traits. These findings indicate that agreeableness, conscientiousness, extraversion, and openness can be significant predictors of the interests to animals and plants.