• Title/Summary/Keyword: global networks

Search Result 881, Processing Time 0.031 seconds

Improving User Satisfaction in Adaptive Multicast Video

  • de Amorim, Marcelo Dias;Duarte, Otto Carlos M.B.;Pujolle, Guy
    • Journal of Communications and Networks
    • /
    • v.4 no.3
    • /
    • pp.221-229
    • /
    • 2002
  • Adaptability is the most promising feature to be applied in future robust multimedia applications. In this paper, we propose the Direct Algorithm to improve the degree of satisfaction at heterogeneous receivers in multi-layered multicast video environments. The algorithm relies on a mechanism that dynamically controls the rates of the video layers and is based on feedback control packets sent by the receivers. The algorithm also addresses scalability issues by implementing a merging procedure at intermediate nodes in order to avoid packet implosion at the source in the case of large multicast groups. The proposed scheme is optimized to achieve high global video quality and reduced bandwidth requirements. We also propose the Direct Algorithm with a virtual number of layers. The virtual layering scheme induces intermediate nodes to keep extra states of the multicast session, which reduces the video degradation for all the receivers. The results show that the proposed scheme leads to improved global video quality at heterogeneous receivers with no cost of extra bandwidth.

Reconstruction of Terrestrial Water Storage of GRACE/GFO Using Convolutional Neural Network and Climate Data

  • Jeon, Woohyu;Kim, Jae-Seung;Seo, Ki-Weon
    • Journal of the Korean earth science society
    • /
    • v.42 no.4
    • /
    • pp.445-458
    • /
    • 2021
  • Gravity Recovery and Climate Experiment (GRACE) gravimeter satellites observed the Earth gravity field with unprecedented accuracy since 2002. After the termination of GRACE mission, GRACE Follow-on (GFO) satellites successively observe global gravity field, but there is missing period between GRACE and GFO about one year. Many previous studies estimated terrestrial water storage (TWS) changes using hydrological models, vertical displacements from global navigation satellite system observations, altimetry, and satellite laser ranging for a continuity of GRACE and GFO data. Recently, in order to predict TWS changes, various machine learning methods are developed such as artificial neural network and multi-linear regression. Previous studies used hydrological and climate data simultaneously as input data of the learning process. Further, they excluded linear trends in input data and GRACE/GFO data because the trend components obtained from GRACE/GFO data were assumed to be the same for other periods. However, hydrological models include high uncertainties, and observational period of GRACE/GFO is not long enough to estimate reliable TWS trends. In this study, we used convolutional neural networks (CNN) method incorporating only climate data set (temperature, evaporation, and precipitation) to predict TWS variations in the missing period of GRACE/GFO. We also make CNN model learn the linear trend of GRACE/GFO data. In most river basins considered in this study, our CNN model successfully predicts seasonal and long-term variations of TWS change.

The Dynamics of Research Output by Indonesian Scientist, Period of 1945-2021

  • Prakoso Bhairawa, Putera;Ida, Widianingsih;Sinta, Ningrum;Suryanto, Suryanto;Yan, Rianto
    • Asian Journal of Innovation and Policy
    • /
    • v.11 no.3
    • /
    • pp.397-420
    • /
    • 2022
  • This research was conducted by applying a bibliometric analysis to determine the dynamics of research topics from ten percent of research output (international publications) generated by Indonesian scientists from the period of 1945-2021. This study utilizes VOSviewers version 1.6.18 for analysis and visualization of bibliometric networks. The research results indicate that 50.24% of Indonesian international publications are published in the form of articles, with subjects such as: Agricultural and Biological Sciences, Medicine, and Earth and Planetary Sciences as the most dominating subject areas. Regarding the author, Tjia, MO from Bandung Institute of Technology was acknowledged as the top author in terms of the number of publications produced for two periods. The article entitled "Global, regional, and national prevalence of overweight and obesity in children and adults during 1980-2013: A systematic analysis for the Global Burden of Disease Study 2013" (Ng et al., 2014) became the most cited one.

The Impact of Entrepreneurial Orientation of Korean SME's Sequential Investment in Vietnam : Focusing on the mediating roles of international market orientation and investment performance (베트남 투자 중소기업의 기업가정신 지향성이 후속투자에 미치는 영향 : 국제시장 지향성과 투자성과의 매개효과를 중심으로)

  • Hyun-Yong Park;Sung-Tae Ma;Jeong Hugh HAN
    • Korea Trade Review
    • /
    • v.45 no.6
    • /
    • pp.1-22
    • /
    • 2020
  • This paper analyzes the influence of entrepreneurial orientation, international market orientation, and investment performance of Korean SMEs in Vietnam on sequential investment. As a result of analyzing the research model using PLS SEM, it was found that Korean SMEs make sequential investments based on investment performance rather than entrepreneurial orientation or international market orientation. In addition, entrepreneurial orientation increased internationa market orientation and had a positive effect on investment performance, which was found to have a positive effect on sequential investment. Through this study, it was clarified that there is a difference between the determinants of initial investment and sequential investment, and it was confirmed that Korean companies show stable and strategic sequential investment tendency rather than proactive and bold investment in Vietnam. In addition, the mediating effect of international market orientation and investment performance in sequential investment was confirmed. In addition, it was confirmed that entrepreneurial orientation was a valid factor in the indirect effect of sequential investment. In the future, for high entrepreneurial orientation Korean companies entered the Vietnamese market, there will be a need for policy support to provide information on Global Value Chain in Vietnam and establish networks on the country.

Abnormal Coating Buildup on Si Bearing Steels in Zn Pot During Line Stop

  • Weimin Zhong;Rob Dziuba;Phil Klages;Errol Hilado
    • Corrosion Science and Technology
    • /
    • v.23 no.2
    • /
    • pp.83-92
    • /
    • 2024
  • A hot-dip simulator was utilized to replicate abnormal coating buildup observed during line stops at galvanize lines, assessing the influence of processing conditions on buildup (up to 14 mm/side). Steel samples from 19 coils (comprising IF, BH, LCAK, HSLA, DP600-DP1180, Si: 0.006 - 0.8 wt%, P: 0.009 - 0.045 wt%) were examined to explore the phenomenon of heavy coating growth. It was discovered that heavy coating buildup (~3 mm/h) and rapid strip dissolution (~0.17 mm/h) in a GA or GI pot can manifest with specific combinations of steel chemistry and processing conditions. The results reveal the formation of a unique coating microstructure, characterized by a blend of bulky Zeta crystals and free Zn pockets/networks due to the "Sandlin" growth mechanism. Key variables contributing to abnormal coating growth include steel Si content, anneal temperature, dew point in heating and soaking furnaces, Zn pot temperature, Zn bath Al%, and cold-rolling reduction%. At ArcelorMittal Dofasco galvanize lines, an automatic online warning system for operators and special scheduling for incoming Si-bearing steels have been implemented, effectively preventing further heavy buildup occurrences.

Shadow Libraries: A Bibliometric Analysis of Black Open Access Phenomenon (2011: 2023)

  • Safinaz Mahmoud Elroukh
    • International Journal of Computer Science & Network Security
    • /
    • v.24 no.5
    • /
    • pp.21-32
    • /
    • 2024
  • This study analyzes the global literature on the black open-access phenomenon from 2011 to 2023. A bibliometric analysis was conducted using the Scopus database. The search strategy employed advanced queries with multiple synonymous terms to ensure exhaustive retrieval of relevant documents. The VOSviewer software was employed to visualize the co-occurrence networks. The findings reported 90 papers published during the study period. An evolving scholarly landscape was revealed, with heightened attention from 2016 onwards, peaking in 2017, 2021, and 2023. Articles constitute 83.3% of the total published documents. Singh and Srichandan are prolific authors, with 11.2% of the total publications. The United States contributes 18.9% of the papers, followed by India and Spain. Information Development and Scientometrics are pivotal journals in scholarly discussions about this scope, contributing 4.4% of publications. Co-occurrence network visualization revealed "Sci-Hub" and "open access" as the most used keywords in the global literature. The findings underscore the need for additional research to discover innovative business models to safeguard intellectual property rights while meeting researchers' evolving needs. The importance of this paper comes from being the first bibliometric study analyzing international literature related to this phenomenon, which provides a basis for future research efforts and policymaking.

Toward a Social Sciences Methodology for Electronic Survey Research on the Internet or Personal Computer check (사회과학 연구에 있어 인터넷 및 상업용 통신망을 이용한 전자설문 조사방법의 활용)

  • Hong Yong-Gee;Lee Hong-Gee;Chae Su-Kyung
    • Management & Information Systems Review
    • /
    • v.3
    • /
    • pp.287-316
    • /
    • 1999
  • Cyberspace permits us to more beyond traditional face-to-face, mail and telephone surveys, yet still to examine basic issues regarding the quality of data collection: sampling, questionnaire design, survey distribution, means of response, and database creation. This article address each of these issues by contrasting and comparing traditional survey methods(Paper-and-Pencil) with Internet or Personal Computer networks-mediated (Screen-and-Keyboard) survey methods also introduces researchers to this revolutionary and innovative tool and outlines a variety of practical methods for using the Internet or Personal Computer Networks. The revolution in telecommunications technology has fostered the rapid growth of the Internet all over the world. The Internet is a massive global network and comprising many national and international networks of interconnected computers. The Internet or Personal Computer Networks could be the comprehensive interactive tool that will facilitate the development of the skills. The Internet or Personal Computer Networks provides a virtual frontier to expand our access to information and to increase our knowledge and understanding of public opinion, political behavior, social trends and lifestyles through survey research. Comparable to other technological advancements, the Internet or Personal Computer Networks presents opportunities that will impact significantly on the process and quality of survey research now and in the twenty-first century. There are trade-offs between traditional and the Internet or Personal Computer Networks survey. The Internet or Personal Computer Networks is an important channel for obtaining information for target participants. The cost savings in time, efforts, and material were substantial. The use of the Internet or Personal Computer Networks survey tool will increase the quality of research environment. There are several limitations to the Internet or Personal Computer Network survey approach. It requires the researcher to be familiar with Internet navigation and E-mail, it is essential for this process. The use of Listserv and Newsgroup result in a biased sample of the population of corporate trainers. However, it is this group that participates in technology and is in the fore front of shaping the new organizations of interest, and therefore it consists of appropriate participants. If this survey method becomes popular and is too frequently used, potential respondents may become as annoyed with E-mail as the sometimes are with mail survey and junk mail. Being a member of the Listserv of Newsgroup may moderate that reaction. There is a need to determine efficient, effective ways for the researcher to strip identifiers from E-mail, so that respondents remain anonymous, while simultaneously blocking a respondent from responding to a particular survey instrument more than once. The optimum process would be on that is initiated by the researcher : simple, fast and inexpensive to administer and has credibility with respondents. This would protect the legitimacy of the sample and anonymity. Creating attractive Internet or Personal Computer Networks survey formats that build on the strengths of standardized structures but also capitalize on the dynamic and interactive capability of the medium. Without such innovations in survey design, it is difficult to imagine why potential survey respondents would use their time to answer questions. More must be done to create diverse and exciting ways of building an credibility between respondents and researchers on the Internet or Personal Computer Networks. We believe that the future of much exciting research is based in the Electronic survey research. The ability to communicate across distance, time, and national boundaries offers great possibilities for studying the ways in which technology and technological discourse are shaped. used, and disseminated ; the many recent doctoral dissertations that treat some aspect of electronic survey research testify to the increase focus on the Internet or Personal Computer Networks. Thus, scholars should begin a serious conversation about the methodological issues of conducting research In cyberspace. Of all the disciplines, Internet or Personal Computer Networks, emphasis on the relationship between technology and human communication, should take the lead in considering research in the cyberspace.

  • PDF

An Empirical Analysis on The Effects of Partner Selection on Structuring, Management on Stability in Global Alliance Networks of Korean Companies (글로벌 제휴네트워크에서 파트너선정이 구조화, 제휴관리, 제휴안정도에 미치는 영향에 관한 실증연구)

  • Jeong, Jongsik
    • International Commerce and Information Review
    • /
    • v.16 no.4
    • /
    • pp.263-280
    • /
    • 2014
  • The dynamics of global alliance networks can be analyzed in numerous ways. We have chosen to approach it in terms of alliance stability. Although increasing academic attention has been devoted to the alliance dynamics field, the majority of prior research has neither contributed to a coherent knowledge foundation(an academic gap) nor provided adequate answers to managerial questions(a managerial relevance gap). We respond to their call for research by developing an integrated process model that integrates various studies on alliance stability. The primary tasks were (1) to characterize and conceptualize the stability concept to fill the academic gap, and (2) to identify critical endogenous factors underlying alliance stability over the different developmental stages to fill the managerial gap. Knowledge acquired in this paper is also expected to offer alliance managers and practitioners some valuable implications as they strive for stable and successful collaborative relationships. As one of the basic arguments, stability has been viewed as a necessary condition for the achievement of collaborative objectives. When firms form, implement, adjust and evaluate their alliances, they should have the goal of stability in mind. At the same time, management should be in a position to determine the specific actions needed for stability at any given moment in the alliance's lifetime.

  • PDF

Proposal of a Step-by-Step Optimized Campus Power Forecast Model using CNN-LSTM Deep Learning (CNN-LSTM 딥러닝 기반 캠퍼스 전력 예측 모델 최적화 단계 제시)

  • Kim, Yein;Lee, Seeun;Kwon, Youngsung
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.21 no.10
    • /
    • pp.8-15
    • /
    • 2020
  • A forecasting method using deep learning does not have consistent results due to the differences in the characteristics of the dataset, even though they have the same forecasting models and parameters. For example, the forecasting model X optimized with dataset A would not produce the optimized result with another dataset B. The forecasting model with the characteristics of the dataset needs to be optimized to increase the accuracy of the forecasting model. Therefore, this paper proposes novel optimization steps for outlier removal, dataset classification, and a CNN-LSTM-based hyperparameter tuning process to forecast the daily power usage of a university campus based on the hourly interval. The proposing model produces high forecasting accuracy with a 2% of MAPE with a single power input variable. The proposing model can be used in EMS to suggest improved strategies to users and consequently to improve the power efficiency.

An Empirical Study on Effects of Global Alliance Networks' Motives on Firm's Capabilities, Partner's Capabilities, Operating Structures, and Performances of Korean Companies (글로벌 제휴네트워크 추진 동기가 기업 역량, 파트너 역량, 운영구조, 제휴 성과에 미치는 영향에 관한 실증연구)

  • Jeong, Jong-Sik
    • International Commerce and Information Review
    • /
    • v.14 no.2
    • /
    • pp.249-269
    • /
    • 2012
  • The focus of our work is to identify and understand the drivers of alliance performance so that businesses can maximize their chances of a successful alliance-an area that has received little attention in empirical modeling. Although both conceptual and applied research on alliances has increased, an empirically tested comprehensive theoretical model that explains alliance performance has yet to be developed. Using five salient perspective, namely market power theory, transaction cost theory, the resource-based view, institutional theory, real option theory, this paper attempts to provide a theoretical rationale linking motives of global alliance networks on firm's capabilities, partner's capabilities, operating structures, and performances of Korean companies. The key contribution of this study is that it paints a picture of what matters in driving alliance performance. Our work shows the complex nature of driving performance and the interplay of firm's capabilities, partner's capabilities, and operating structures for understanding alliance performances. This study has given us a small but significant step forward towards understanding the intricacies of alliance performance. We are now better able to understand the respective roles played by various alliance factors and derive insights that lead to improved alliance performance.

  • PDF