• Title/Summary/Keyword: small world network

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orean Small Telescope Network (소형망원경 네트워크, 소망넷)

  • Im, Myungshin;Kim, Yonggi;Kang, Wonseok;Lee, Chung-Uk;Lee, Heewon;Pak, Soojong;Shim, Hyunjin;Sung, Hyun-Il;Kim, Taewoo;Lee, Seong-Kook J.;Lim, Gu;Paek, Gregory S.H.;Seo, Jinguk;Yoon, Joh-Na;Kim, Dohyeong
    • The Bulletin of The Korean Astronomical Society
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    • v.46 no.1
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    • pp.48.3-48.3
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    • 2021
  • SomangNet is a project that started in 2020 with a network of ten 0.4 to 1.0 m telescopes owned by Korean institutes. By coordinating observations with multiple facilities around the world, we hope to maximize the usefulness of small telescopes which are still competitive for carrying out time-domain astronomy projects. In this talk, we will give an overview of the project, outlining SomangNet facilities, its organization, and current science projects. We hope to open SomangNet for common use in 2021B, and we will present our plan regarding the use of SomangNet.

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Access efficiency of small sized files in Big Data using various Techniques on Hadoop Distributed File System platform

  • Alange, Neeta;Mathur, Anjali
    • International Journal of Computer Science & Network Security
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    • v.21 no.7
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    • pp.359-364
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    • 2021
  • In recent years Hadoop usage has been increasing day by day. The need of development of the technology and its specified outcomes are eagerly waiting across globe to adopt speedy access of data. Need of computers and its dependency is increasing day by day. Big data is exponentially growing as the entire world is working in online mode. Large amount of data has been produced which is very difficult to handle and process within a short time. In present situation industries are widely using the Hadoop framework to store, process and produce at the specified time with huge amount of data that has been put on the server. Processing of this huge amount of data having small files & its storage optimization is a big problem. HDFS, Sequence files, HAR, NHAR various techniques have been already proposed. In this paper we have discussed about various existing techniques which are developed for accessing and storing small files efficiently. Out of the various techniques we have specifically tried to implement the HDFS- HAR, NHAR techniques.

Distributed estimation over complex adaptive networks with noisy links

  • Farhid, Morteza;Sedaaghi, Mohammad H.;Shamsi, Mousa
    • Smart Structures and Systems
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    • v.19 no.4
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    • pp.383-391
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    • 2017
  • In this paper, we investigate the impacts of network topology on the performance of a distributed estimation algorithm, namely combine-then-adaptive (CTA) diffusion LMS, based on the data with or without the assumptions of temporal and spatial independence with noisy links. The study covers different network models, including the regular, small-world, random and scale-free whose the performance is analyzed according to the mean stability, mean-square errors, communication cost (link density) and robustness. Simulation results show that the noisy links do not cause divergence in the networks. Also, among the networks, the scale free network (heterogeneous) has the best performance in the steady state of the mean square deviation (MSD) while the regular is the worst case. The robustness of the networks against the issues like node failure and noisier node conditions is discussed as well as providing some guidelines on the design of a network in real condition such that the qualities of estimations are optimized.

Study of the Effects of Co-Patent Network Factors on Technological Innovation: Focus on IT industry in Korea (공동 특허 출원인간 협력 요인이 기술혁신성과에 미치는 영향 분석: 우리나라 정보통신업을 중심으로)

  • JU, Seong-Hwan;SEO, Hwan-Joo
    • Journal of Technology Innovation
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    • v.25 no.4
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    • pp.211-238
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    • 2017
  • This study was conducted using social network analysis, variance analysis, and regression analysis to investigate the effects of cooperation between innovators on technical performance. Based on data of joint applicants filed with the Korean Intellectual Property Office from 2009 to 2012, we derive network structural variables and characteristic variables, and identify network characteristics that affect the overall network structural type, roles for each subject of innovation, and innovation performance. The findings are as follows: ⅰ) The network of this study is a distributed, small-world network within which relatively small groups of innovators are distributed. ⅱ) Universities were found to play the most important role in cooperation, but diversity of cooperating partners exhibited similar effects. ⅲ) It was shown that access to quick and accurate knowledge from familiar partners exhibits a more positive influence on generating innovative performance than unfamiliar knowledge from a variety of cooperating partners in non-familiar fields.

Marketing Strategy of the Small Business Adaptation to Quarantine Limitations in the Sphere of Trade Entrepreneurship

  • Ivanova, Nataliia;Popelo, Olha;Avhustyn, Ruslan;Rusak, Olena;Proshchalykina, Alina
    • International Journal of Computer Science & Network Security
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    • v.22 no.1
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    • pp.149-160
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    • 2022
  • The article considers the peculiarities of developing a marketing strategy for the adaptation of small businesses to quarantine restrictions in the field of commercial entrepreneurship. The importance of reformatting the existing marketing strategy in connection with the change of key conditions of trade activity with the introduction of quarantine restrictions due to the covid19 virus epidemic is substantiated. Quarantine restrictions and the temporary introduction of lockdown in various countries around the world, including Ukraine, have not only caused a crisis for small businesses. But they became a shock therapy and accelerated the digitalization of retail. Trends in digitalization and development of digital infrastructure allow both to adapt the structures of commercial entrepreneurship to the current conditions, and set directions for development in the long run. Particular attention in the article is paid to changing the business model and automation of sales processes based on the introduction of vending. The preconditions and existing experience of vending in Ukraine are analyzed. An outline of the business model of the project for the sale of goods through vending machines has been developed.

A Hierarchical Model for Mobile Ad Hoc Network Performability Assessment

  • Zhang, Shuo;Huang, Ning;Sun, Xiaolei;Zhang, Yue
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.10 no.8
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    • pp.3602-3620
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    • 2016
  • Dynamic topology is one of the main influence factors on network performability. However, it was always ignored by the traditional network performability assessment methods when analyzing large-scale mobile ad hoc networks (MANETs) because of the state explosion problem. In this paper, we address this problem from the perspective of complex network. A two-layer hierarchical modeling approach is proposed for MANETs performability assessment, which can take both the dynamic topology and multi-state nodes into consideration. The lower level is described by Markov reward chains (MRC) to capture the multiple states of the nodes. The upper level is modeled as a small-world network to capture the characteristic path length based on different mobility and propagation models. The hierarchical model can promote the MRC of nodes into a state matrix of the whole network, which can avoid the state explosion in large-scale networks assessment from the perspective of complex network. Through the contrast experiments with OPNET simulation based on specific cases, the method proposed in this paper shows satisfactory performance on accuracy and efficiency.

Development of Small Farms in the Agro-Industrial Complex

  • Petrunenko, Iaroslav;Pohrishchuk, Oleg;Plotnikova, Mariia;Zolotnytska, Yuliia;Dligach, Andrii
    • International Journal of Computer Science & Network Security
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    • v.21 no.3
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    • pp.287-294
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    • 2021
  • Modern small farms are important link components in the structure of the world agro-industrial complex. It ensures the food and nutritional sustainability of the country exclusively at the local regional level. The purpose of the research is to examine the role of farming in ensuring nutritional security and food stability based on the analysis of the Food Sustainability Index (FSI). Research methods: modeling, abstraction, analogy, analysis, synthesis, formalization, logical abstraction, theoretical cognition, systematization and classification, abstract-logical, etc. Results. Having analyzed the Food Sustainability Index for 2018, it has been established that there is a lack of a clear relationship between the pace of economic development and the level of food and nutritional sustainability. In addition, this study has identified the countries with the largest number of small farms, as well as the number of farms within the region. The correlation between the size of the farm and the area of agricultural land that it cultivates has been determined. The problems faced by small farms in the process of their activity have been analyzed. The programs implemented in the field of agro-industrial complex development by international profile institutions have been systematized. Particularly, the regional structure of agricultural development programs under the guidance of IFAD is defined, as well as the areas to which they are directed. Specific measures taken by governments to stimulate the development of small farms have been outlined. Reasonable conclusions have been formed based on the study. The direction of future research is seen in the assessment of the export potential of small farms in terms of range, volume of export deliveries and geographical direction of movement of their products.

Topological and Statistical Analysis for the High-Voltage Transmission Networks in the Korean Power Grid

  • Kang, Seok-Gu;Yoon, Sung-Guk
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.42 no.4
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    • pp.923-931
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    • 2017
  • A power grid is one of the most complex networks and is critical infrastructure for society. To understand the characteristics of a power grid, complex network analysis has been used from the early 2000s mainly for US and European power grids. However, since the power grids of different countries might have different structures, the Korean power grid needs to be examined through complex network analysis. This paper performs the analysis for the Korean power grid, especially for high-voltage transmission networks. In addition, statistical and small-world characteristics for the Korean power grid are analyzed. Generally, the Korean power grid has similar characteristics to other power grids, but some characteristics differ because the Korean power grid is concentrated in the capital area.

An Analysis on the Characteristics of Global Automotive Production Network using the OECD Trade in Value Added Data (OECD 부가가치 기준 교역자료를 이용한 자동차산업 글로벌 생산 네트워크의 특성 분석)

  • Jeong, Jun Ho;Jo, Hyung Je
    • Journal of the Economic Geographical Society of Korea
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    • v.19 no.3
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    • pp.491-511
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    • 2016
  • This paper attempts to understand the nature and dynamics of global value chains in the auto industry using the OECD TiVA 2015 edition on the bilateral foreign value added in exports over the period 1995-2011 and employing the techniques of social network analysis such as the computation of network measures and visualization of value added trade flows. It is shown that there has been a tendency towards increasing production fragmentation both within and across regions. The automotive value-added network is found to have small-world properties with a hierarchical, clustered and dense structure. The differences among the US, Germany and China as major suppliers of foreign value added in global automotive value chains are remarkably revealed. Although the fragmentation of production has been developed on a global scale, a dichotomous tension between center and periphery and domestic and foreign capital lies behind it.

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The Recent Trend in the World Air Transport Market and a Two-Airline Policy in Korea (세계민항계의 최적 동향과 우리나라 복수민항체제의 발전방향)

  • 이영혁
    • Journal of Korean Society of Transportation
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    • v.9 no.2
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    • pp.57-74
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    • 1991
  • Deregulation privatization regionalism and globalization are the specific examples of the recent trends in the world air transport market. As encouraged by the international trends and the domestic policy of promoting market mechanism Korean has been driving a two-airline policy since 1989. But due to the absence of experience and philosophy about the airline co-mpetition both Korean government and the two airlines have been criticized for failing to set fair-competition rules and for struggling to secure air service rights regardless of national interest. Therefore this study shows the costs and benefits of a two-airline policy in a small count-ry reviews the empirical studies about the cost structure of American and Canadian airlines and analyzes the economic consequences of allocating air service rights between two airlines. The policy recommendations are (1) removing government restrictions and expanding ai-rport facilities to develop the domestic market (2) retaining the two-airline policy in the in-ternational market (3) increasing traffic density rather than expanding network for the small airline (4) improving comparative advantage through a global alliance and a technological innovation for the big airline and (5) building an official committee for co-ordinating the two airlines' interests.

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