• Title/Summary/Keyword: BIG4

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GRADIENT RICCI ALMOST SOLITONS ON TWO CLASSES OF ALMOST KENMOTSU MANIFOLDS

  • Wang, Yaning
    • Journal of the Korean Mathematical Society
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    • v.53 no.5
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    • pp.1101-1114
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    • 2016
  • Let ($M^{2n+1}$, ${\phi}$, ${\xi}$, ${\eta}$, g) be a (k, ${\mu}$)'-almost Kenmotsu manifold with k < -1 which admits a gradient Ricci almost soliton (g, f, ${\lambda}$), where ${\lambda}$ is the soliton function and f is the potential function. In this paper, it is proved that ${\lambda}$ is a constant and this implies that $M^{2n+1}$ is locally isometric to a rigid gradient Ricci soliton ${\mathbb{H}}^{n+1}(-4){\times}{\mathbb{R}}^n$, and the soliton is expanding with ${\lambda}=-4n$. Moreover, if a three dimensional Kenmotsu manifold admits a gradient Ricci almost soliton, then either it is of constant sectional curvature -1 or the potential vector field is pointwise colinear with the Reeb vector field.

The Technology-based Overseas Startup Analysis and Activation Strategy using Big data (빅데이타 기술기반 해외창업 실태분석 및 활성화 전략)

  • Choi, Jungsuk;Seo, Sang-Hyeok
    • Annual Conference of KIPS
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    • 2019.10a
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    • pp.633-636
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    • 2019
  • 최근 글로벌화를 지향하는 국내 스타트업 중에 사업기획 단계에서부터, 법인설립, 현지마케팅 등을 해외에서 시작하는 해외창업 스타트업이 늘고 있다. 또한 4차 산업혁명의 진전에 따라 각종 IoT·센서 등에서 발생하는 대량의 데이터가 데이터 기반 산업·경제활성화를 견인하는 원동력으로 작용할 전망이다. 해외창업은 언어 장벽, 이질적 문화와 제도 등으로 성공하기 어려움에도 불구하고, 성공사례들이 종종 파악되고 있다. 따라서, 이런 사례가 파악되고 있는 미국, 인도, 일본, 싱가포르 등 4개국에서의 해외창업 성공사례들을 질적 분석을 통해 성공요인을 도출하고 해외창업 활성화 전략을 제시하였다.

Formation of Corporate Governance in Korea: The Rise of Chaebols (1910-1980)

  • Gwon, Jae-Hyun
    • Asian Journal of Business Environment
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    • v.5 no.4
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    • pp.67-72
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    • 2015
  • Purpose - This aim of this study is to examine how conglomerates in Korea have evolved from the perspective of institutional economics. The growth of the economy, dominated by large conglomerates, is projected in light of the dynamic equilibrium between government and capitalists. Research design, data, and methodology - The historical formation of big business groups is examined in chronological order. For the analysis, we divide the assessment into three different eras: Japanese colonial rule, liberation up to the civil war, and the fast growing period since the military coup. Each period is viewed as a dynamic equilibrium that is shaped by economic agents. Results and Conclusion - Despite the rise of modern commerce during the colonial era, contemporary conglomerates came into being with the "enemy property" allotted by the government. Around the civil war, the government coexisted with prototype conglomerates through foreign aid. As the external aid decreased, the system could not be sustained anymore, thus the military coup took place. The reinstated strong bond between government and the conglomerates has shaped the forms of the modern conglomerates thereafter.

Contribution of Electrophilic Interference on Solvolytic Reactions in Fluorinated Alcohol Mixtures

  • Dae Dong Sung;Yang Hee Kim;Kyu Chul Kim;Tae Seop Uhm;Ikchoon Lee
    • Bulletin of the Korean Chemical Society
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    • v.12 no.4
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    • pp.449-453
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    • 1991
  • The degree of electrophilic interference on the solvolytic reactions of model substrates has been studied in fluorinated alcohol solvent mixtures. With variation of solvent composition of 1,1,1,3,3,3-hexafluoro-2-propanol(HFP) and 2-propanol (PrOH) mixtures, the magnitude of electrophilic solvent assistance was changed inversely with the degree of nucleophilic solvent assistance. The contribution of electrophilic interference for 2-adamantyl tosylate showed higher than tert-butyl chloride in HFP-PrOH mixtures. Through a correlation of nucleophilic solvent assistance and electrophilic solvent assistance based on the method of double differences, HFP-PrOH mixture showed a big discrepancy from non-fluorinated alcohol systems.

Masonry building behaviors during the February 6-12, 2017 Ayvacik-Çanakkale Earthquakes

  • Ural, Ali
    • Earthquakes and Structures
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    • v.17 no.4
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    • pp.355-363
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    • 2019
  • Masonry structures in the rural areas of Turkey often damaged due to moderate and big earthquakes. After every earthquake many scientists made field investigations on the earthquake performance of these structures and gave many useful information on construction techniques. However, the newly constructed masonry buildings are still not suitable for the suggested techniques, and they are still in danger against future earthquakes. Five moderate earthquakes of moment magnitude Mw 5.3, 5.3, 5.2, 5.0, and 5.3 struck the Ayvacik-Çanakkale District of Turkey between 6 and 12 February, 2017. More than a thousand of aftershocks were occurred and most of the masonry buildings in the villages nearby main shock epicenter were affected. The author went to the earthquake field and investigated the earthquake performances of masonry structures. This paper presents the recorded acceleration data, acceleration response spectra, and the seismological aspects of these earthquakes. Besides, case studies of damaged stone masonry buildings, and failure mechanisms are discussed with illustrated photos which were taken during the field investigations. It is concluded that the damaged masonry buildings were not designed and constructed properly in accordance with the Turkish building codes or similar specifications.

A Study on the influence of Productivity improvement of middle and small sized company's learning organization on productivity (중소기업 학습조직 활성화가 생산성에 미치는 영향에 관한 연구)

  • Jo, Yu-Jin;Kang, Kyung-Sik
    • Journal of the Korea Safety Management & Science
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    • v.19 no.4
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    • pp.283-290
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    • 2017
  • In knowledge information society entering global unlimited competition era, our middle and small sized companies are the base of national and enterprise competitiveness and core base of national economy as an origin of jobs. The competitiveness of middle and small sized companies is so important to decide the level of the competitiveness of the whole industries, but the gap from big sized company is much low in comparison with advanced countries from angles of important factors of enterprise growth, productivity and technological competitiveness, so, it's urgent to improve the competitiveness through productivity enhancement. The purpose of this research is to do a positive study on effects of learning organization management outcomes of middle and small sized company on enterprise productivity among various types of outcome brought for strengthening of enterprise competitiveness. It confirmed learning organization has functions and usefulness as a management tool bringing positive effects on enterprise productivity through the Productivity improvement.

A study on the effects of continuing business intent of third party logistics company on logistics outcomes (제3자 물류기업의 지속적 거래의도가 물류성과에 미치는 영향에 관한 연구)

  • Yang, Hong-Jun;Kang, Kyung-Sik
    • Journal of the Korea Safety Management & Science
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    • v.18 no.4
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    • pp.123-130
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    • 2016
  • In global competition composition changing rapidly, domestic industry faces changes and logistics industry, one of service industries, is recognized as an important factor for development of domestic industry and national economy. At this moment, companies must suggest differentiated service, strategies, etc. so as to create and maintain competitive advantages in comparison with other companies. The requirements preannounce big movement of third party logistics market. Therefore, government, logistics industry and academic world have suggested lots of studies so as to vitalized third party logistics market. The purposes of this research are to verify that innovative changes are necessary to be existing in fierce competition of third party logistics market and analyze the effects of third party logistics on logistics outcomes so as to form continuous relations with shipper.

Analysis of Thermal and Flow Characteristic in Ice Storage Tank (빙축열조 내부의 열적유동 특성 해석)

  • Kim, Y.I.;Hong, H.K.;Bai, C.H.;Kim, Y.I.;Yoon, H.S.
    • The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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    • v.17 no.4
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    • pp.369-376
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    • 1988
  • Among several methods to solve the unbalanced electric power load, the Ice Storage System (ISS) for the air conditioning is relatively easy to realize and gives big effect on balancing the electric power load. The goals of this study are to develop the practical ISS for the air conditioning through the design, manufacturing and performance test of the experimental ISS (size $0.335m^3$, cold storage capacity 14200 kcal, IPF 0.4). Thermal fluid motion inside the ice storage tank during cooling storage and cooling release are studied. The data are analyzed by the dispersion analysis and optimal design conditions are derived from the result.

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A Vehicle Recognition Method based on Radar and Camera Fusion in an Autonomous Driving Environment

  • Park, Mun-Yong;Lee, Suk-Ki;Shin, Dong-Jin
    • International journal of advanced smart convergence
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    • v.10 no.4
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    • pp.263-272
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    • 2021
  • At a time when securing driving safety is the most important in the development and commercialization of autonomous vehicles, AI and big data-based algorithms are being studied to enhance and optimize the recognition and detection performance of various static and dynamic vehicles. However, there are many research cases to recognize it as the same vehicle by utilizing the unique advantages of radar and cameras, but they do not use deep learning image processing technology or detect only short distances as the same target due to radar performance problems. Radars can recognize vehicles without errors in situations such as night and fog, but it is not accurate even if the type of object is determined through RCS values, so accurate classification of the object through images such as cameras is required. Therefore, we propose a fusion-based vehicle recognition method that configures data sets that can be collected by radar device and camera device, calculates errors in the data sets, and recognizes them as the same target.

Proposal of An Artificial Intelligence Farm Income Prediction Algorithm based on Time Series Analysis

  • Jang, Eun-Jin;Shin, Seung-Jung
    • International journal of advanced smart convergence
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    • v.10 no.4
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    • pp.98-103
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    • 2021
  • Recently, as the need for food resources has increased both domestically and internationally, support for the agricultural sector for stable food supply and demand is expanding in Korea. However, according to recent media articles, the biggest problem in rural communities is the unstable profit structure. In addition, in order to confirm the profit structure, profit forecast data must be clearly prepared, but there is a lack of auxiliary data for farmers or future returnees to predict farm income. Therefore, in this paper we analyzed data over the past 15 years through time series analysis and proposes an artificial intelligence farm income prediction algorithm that can predict farm household income in the future. If the proposed algorithm is used, it is expected that it can be used as auxiliary data to predict farm profits.