• Title/Summary/Keyword: current science issue

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A Study Process of SCM and Relation development other systems (SCM(Supply Chain Management)의 프로세스연구와 타 시스템과의 연계성 연구)

  • 박주식;이태우;연찬호;강경식
    • Journal of the Korea Safety Management & Science
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    • v.3 no.1
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    • pp.81-91
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    • 2001
  • In supply chain management, coordination between a manufacture and suppliers Is regarded as the most important issue when partnership of organizations of considered. This paper Introduces the current status of SCM in terms of physical systems, relation with other solution systems as well as the general history and definitions of SCM. Researches are categorized into deterministic, stochastic, and several future research areas are discussed in the paper.

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The Viability of the Malaysian Penal Code in Handling Physical Damage Caused by Malware

  • Rahman, Rizal;Zakaria, Mohd Sophian
    • International Journal of Computer Science & Network Security
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    • v.21 no.5
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    • pp.52-56
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    • 2021
  • There is no assurance that malware could only cause virtual damage to computer programs and data as its potential is endless. However, legal provisions were earlier developed to cater to either a physical damage caused by a physical action or a virtual damage caused by a virtual action. When crossovers occur, it becomes quite uncertain as to how viable the current laws are in handling this matter. The author seeks to address the issue from the perspective of the laws of Malaysia.

Effect of oxide film on ECT detectability of surface IGSCC in laboratory-degraded alloy 600 steam generator tubing

  • Lee, Tae Hyun;Ryu, Kyung Ha;Kim, Hong Deok;Hwang, Il Soon;Kim, Ji Hyun;Lee, Min Ho;Choi, Sungyeol
    • Nuclear Engineering and Technology
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    • v.51 no.5
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    • pp.1381-1389
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    • 2019
  • Stress corrosion cracking (SCC) widely found in both primary and secondary sides of steam generator (SG) tubing in pressurized water reactors (PWR) has become an important safety issue. Using eddy-current tests (ECTs), non-destructive evaluations are performed for the integrity management of SG tubes against intergranular SCC. To enhance the reliability of ECT, this study investigates the effects of oxide films on ECT's detection capabilities for SCC in laboratory-degraded SG tubing in high temperature and high pressure aqueous environment.

Optimized Hybrid Modulation Strategy for AC Bypass Transformerless Single-Phase Photovoltaic Inverters

  • Deng, Shuhao;Sun, Yao;Yang, Jian;Zhu, Qi;Su, Mei
    • Journal of Power Electronics
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    • v.16 no.6
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    • pp.2129-2138
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    • 2016
  • The full-bridge inverter, widely used for single-phase photovoltaic grid-connected applications, presents a leakage current issue. Therefore, an AC bypass branch is introduced to overcome this challenge. Nevertheless, existing modulation strategies entail drawbacks that should be addressed. One is the zero-crossing distortion (ZCD) of the AC current caused by neglecting the AC filter inductor voltage. Another is that the system cannot deliver reactive power because the AC bypass branch switches at the power frequency. To address these problems, this work proposes an optimized hybrid modulation strategy. To reduce ZCD, the phase angle of the inverter output voltage reference is shifted, thereby compensating for the neglected leading angle. To generate the reactive power, the interval of the negative power output is calculated using the power factor. In addition, the freewheeling switch is kept on when power is flowing into the grid and commutates at a high frequency when power is fed back to the DC side. In this manner, the dead-time insertion in the high-frequency switching area is minimized. Finally, the performances of the proposed modulation strategy and traditional strategies are compared on a universal prototype inverter. Experimental results validate the theoretical analysis.

A Study of Authorized Stockage List Selection using Market Basket Analysis (장바구니 분석을 활용한 ASL 선정 연구)

  • Choi, Myoung-Jin
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.35 no.2
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    • pp.163-172
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    • 2012
  • In this study, It is assumed that customers are both usage unit of spare parts and stores of displaying and selling the goods that are installation unit of having the spare parts. The demand pattern through the effective order of spare parts and issue list in installation unit is investigated based on the assumption. Current ASL (Authorized Stockage List) selection of the army has been conducted in the way of using the analysis result of real usage experiences on spare parts used during the Korea War. For this study, ASL selection criteria and procedures based on army regulations and field manuals are specified. Since the traditional method does not presents the association analysis on spare parts used for the current equipment operating and does not have the clear criterion and analysis system about the ASL selection, in order to solve these problems, it was carried out that the association rule is employed for analyzing relationship between the effective order and issue list of the spare parts in point of the spare parts between usage unit and occurring month about purchase spare parts based on the star-schema table. Finally the new ASL selection way using the analysis result is proposed.

Challenges and Outlook for the UICC-Asian Regional Office

  • Akaza, Hideyuki
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.8
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    • pp.4935-4937
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    • 2013
  • At the United Nations High-level Meeting on Non-communicable Disease Prevention and Control in 2011 the link between health and socioeconomic issues was raised, becoming a global political issue. Health equity is one challenge that has hitherto not been addressed directly, although there is a growing shared recognition that cancer in Asia is an urgent social issue. At the UICC-ARO we are working to promote and widen networks of individuals and organizations in Asia and involve them in cooperation for this purpose. As part of our current activities, we are addressing the question of the "Economic burden of cancer in Asian countries: How should we face the current situation?" from a variety of angles and seeking to bring together a wealth of multidisciplinary knowledge about cancer in Asia and its related socioeconomic factors. It is essential to ensure that the real picture of cancer in Asia, which is currently not accurately understood, is conveyed clearly to all concerned, and also that the differences between cancer in Asia and in the West are highlighted.

Laser Stitch Welding Technology for the Fabrication of Automotive Parts (자동차 부품 제조를 위한 레이저 스티치 용접 기술)

  • Joo, Sung-Min;Bang, Hee-Seon;Han, Jun-Ui;Kim, Kyoung-Hak;Ahn, Byoung-Ho
    • Journal of Welding and Joining
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    • v.31 no.4
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    • pp.1-6
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    • 2013
  • Nowadays, the weight lightening of automotive is required as conserving the environment has become a major worldwide issue. To solve this issue, various researches for the use of light materials(Alalloy, Mgalloy)and ultra high strength steel as substitutes of the current structural material have been carried out. Application of laser stitch welding to the assembly of automotive produces improvement in strength, lightening of body, higher fuel efficiency, lower production cost as well as reduction in assemble line due to its fast welding speed, superior accessible and weld quality. This process overcomes the shortcomings of the current resistance spot welding such as high electricity consumption, electrode replacement, and economical, technical limitation in design and production method of automotives.

Pulse Electrodeposition of Polycrystalline Si Film in Molten CaCl2 Containing SiO2 Nanoparticles

  • Taeho Lim;Yeosol Yoon
    • Journal of Electrochemical Science and Technology
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    • v.14 no.4
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    • pp.326-332
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    • 2023
  • The high cost of Si-based solar cells remains a substantial challenge to their widespread adoption. To address this issue, it is essential to reduce the production cost of solar-grade Si, which is used as raw material. One approach to achieve this is Si electrodeposition in molten salts containing Si sources, such as SiO2. In this study, we present the pulse electrodeposition of Si in molten CaCl2 containing SiO2 nanoparticles. Theoretically, SiO2 nanoparticles with a diameter of less than 20 nm in molten CaCl2 at 850℃ have a comparable diffusion coefficient with that of ions in aqueous solutions at room temperature. However, we observed a slower-than-expected diffusion of the SiO2 nanoparticles, probably because of their tendency to aggregate in the molten CaCl2. This led to the formation of a non-uniform Si film with low current efficiency during direct current electrodeposition. We overcome this issue using pulse electrodeposition, which enabled the facile supplementation of SiO2 nanoparticles to the substrate. This approach produced a uniform and thick electrodeposited Si film. Our results demonstrate an efficient method for Si electrodeposition in molten CaCl2 containing SiO2 nanoparticles, which can contribute to a reduction in production cost of solar-grade Si.

English Education in Korea as an Academic Field: For Its Carnival. (학문으로서 영어교육의 현실과 위상 : 그 카니발을 위하여)

  • 이병민
    • Korean Journal of English Language and Linguistics
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    • v.1 no.1
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    • pp.119-143
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    • 2001
  • The main goal of this paper is to examine the current English education practices in Korea in the broad context of research and academia. Furthermore, it attempts to uncover why English education has not been well established as a field of science in English-related departments and consequently what has been neglected and what issues should be dealt with to increase understanding and to create a more interactive relationship between the university and society. First, the author deals with the influence of ‘folk science’ views in the field of English education by touching on some widely held perceptions and issues. Second, by dealing with the alienation of English education and examining the phenomenon of seeing English education as a secondary field of science in English related departments, an attempt was made to reveal underlying epistemological dualism rooted in Asian cultures. Third, the paper deals with a critical issue related to English education: Exposure and Time. By reviewing and reinterpreting some of basic and fundamental literature with respect to language learning, exposure, and time, the author raises a new issue in English education and proposes new interpretation and an alternative more relativistic viewpoint; he also investigates what should be done to improve English education on the basis of research and science in order to deal with the needs and problems of society.

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Critical Design Issues on the Cathodic Protection Systems of Ships

  • Lee, Ho Il;Lee, Chul Hwan;Jung, Mong Kyu;Baek, Kwang Ki
    • Corrosion Science and Technology
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    • v.6 no.3
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    • pp.90-95
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    • 2007
  • Cathodic protection technology has been widely used on ship's outer hull and inner side of ballast water tanks as a supplementary corrosion protection measure in combination with protective organic coatings. Impressed current cathodic protection system is typically opted for the ship's hull and, sacrificial anode system, for ballast water tanks. The anticipation and interest in cathodic protection system for ships has been surprisingly low-eyed to date in comparison with protective coatings. Computational analysis for the verification of cathodic protection design has been tried sometimes for offshore marine structures, however, in commercial shipbuilding section, decades old design practice is still applied, and no systematic or analytical verification work has been done for that. In this respect, over-rotection from un-erified initial design protocol has been also concerned by several experts. Especially, it was frequently reported in sacrificial anode system that even after full design life time, anode was remaining nearly intact. Another issue for impressed current system, for example, is that the anode shield area design for ship's outer hull should be compromised with actual application situation, because the state-of-the-art design equation is quite impractical from the applicator's stand. Besides that, in this study, some other critical design issues for sacrificial anode and impressed current cathodic protection system were discussed.