• Title/Summary/Keyword: current lead system

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Non-destructive evaluation of concrete quality using PZT transducers

  • Tawie, R.;Lee, H.K.;Park, S.H.
    • Smart Structures and Systems
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    • v.6 no.7
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    • pp.851-866
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    • 2010
  • This paper presents a new concept of using PZT (lead zircornate titanate) transducers as a non-destructive testing (NDT) tool for evaluating quality of concrete. Detection of defects in concrete is very important in order to check the integrity of concrete structures. The electro-mechanical impedance (EMI) response of PZT transducers bonded onto a concrete specimen can be used for evaluating local condition of the specimen. Measurements are carried out by electrically exciting the bonded PZT transducers at high frequency range and taking response measurements of the transducers. In this study, the compression test results showed that concrete specimens without sufficient compaction are likely to fall below the desired strength. In addition, the strength of concrete was greatly reduced as the voids in concrete were increased. It was found that the root mean square deviation (RMSD) values yielded between the EMI signatures for concrete specimens in dry and saturated states showed good agreement with the specimens' compressive strength and permeable voids. A quality metric was introduced for predicting the quality of concrete based on the dry-saturated state of concrete specimens. The simplicity of the method and the current development towards low cost and portable impedance measuring system, offer an advantage over other NDE methods for evaluating concrete quality.

A Consideration for Intellectual Property Rights under Digital Environments (전자상거래에서의 지적재산권에 관한 문제점과 개선방안)

  • Kwon, Sang-Ro
    • International Commerce and Information Review
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    • v.6 no.1
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    • pp.249-265
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    • 2004
  • In the current digital age, most of the countries in the world recognize the electronic business to be a very prospective area in the future and plan to activate for the preoccupation of the business. As a result, this led a rapid increase of the electronic business volume. Electronic business takes place in the cyber space, using internet. However, the intellectual property rights have a high degree of possibility of being infringed as the digitalized intellectual property is easy to receive, copy and transmit in the cyber space. The language structure on the web, represented by HTML, makes easier to copy the intellectual property. And, as the internet has no national boundary, the infringement of the intellectual property rights is easier regardless of country, which could lead to the commercial disputes between the concerned countries. There are in fact many legal disputes nowadays on the infringement of the intellectual property rights in such field as computer programming, infringement of the copyright, business model patent and infringement of the trademark right on the registered name of the domain. It is, therefore, time now to prepare a new theory or legal system to protect the intellectual property rights on copyright, patent and trademark right so as to comply with the digital environment together with such a splendid growth of "electronic business." USA and Germany are nowadays making a significant movement on the legislation of the electronic business, and this study will focus on the legislative contents, judicial precedents and interpretation of law in the above countries.

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Study on the electrical properties in the ceramic of (Sr¡¤Ca)Ti${O}_{2}$ system ((Sr.Ca)Ti${O}_{3}$계 세라믹의 전기적 특성에 관한 연구)

  • 최운식;김용주;이준웅
    • The Transactions of the Korean Institute of Electrical Engineers
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    • v.44 no.12
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    • pp.1610-1616
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    • 1995
  • The (Sr$_{1-x}$ .Ca$_{x}$)TiO$_{3}$(0.05.leq.x.leq.0.2) ceramics were fabricated to form semiconducting ceramics by sintering at about 1350[.deg. C] in a reducing atmosphere (N$_{2}$ gas). After being fired in a reducing atmosphere, metal oxides, CuO, was painted on the both surface of the specimens to diffuse to the grain boundary. They were annealed at 1100[.deg. C] for 2 hours. The 2nd phase formed by thermal diffusing from the surface lead to a very high apparent dielectric constant. The results of the capacitance-valtage measurements indicated that the grain boundary was composed of the continuous insulating layers. The capacitance is almost unchanged below about 20[V], but decreased slowly over 20[V]. The conduction mechanism of the specimens observed in the temperature range of 25~125[.deg. C], and is divided into three regions having different mechanism as the current increased: the region I below 200[V/cm] shows the ohmic conduction. The region II between 200[V/cm] and 2000[V/cm] can be explained by the Poole-Frenkel emission theory, and the region III above 2000[V/cm] is dominated by the tunneling effect.ct.

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Detection and Identification of the Series Arc in an Indoor Wiring System (옥내 배선계통에서 직렬 아크의 검출과 판별)

  • Kim, Woo-Hyun;Wang, Guoming;Kil, Gyung-Suk;Ji, Hong-Keun
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.31 no.6
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    • pp.412-416
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    • 2018
  • Most series arcs lead to electrical fires that cannot be interrupted by circuit breakers, because the arc's current is outside the breaker's operating range. In this paper, experiments were conducted on the detection and identification of series arcs to prevent electrical fires. Plugs and outlets specified in KS C 8305 were deteriorated to replicate arc faults commonly found in fields. The characteristics of series arcs resulting from various types of loose connections were determined by analyzing the frequency spectra and phase distributions of detected arc pulses. The results showed that the simulated arc defects used in this study were more similar to actual arc phenomena than the existing arc generator specified in UL 1699. In addition, loose connections, such as wire-wire, terminal-wire, and outlet-plug, can be identified by phases of $0^{\circ}$, $180^{\circ}$ and $360^{\circ}$, respectively. These phases can be detected by a band pass filter with a frequency range of 5~10 MHz, which can be used as the trip signal for circuit breakers.

Numerical Analysis of MDF for Aluminum Plate Cutting (MDF를 이용한 알루미늄 평판 절개 해석)

  • Lee, Juho
    • Journal of the Korean Society of Propulsion Engineers
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    • v.22 no.6
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    • pp.134-141
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    • 2018
  • In this paper, the possibility of using an MDF (Mild-detonating Fuse) as a linear separation device is studied. An MDF is a small diameter metal (lead) tube filled with explosives (RDX). Aluminum plate cutting experiments are carried out with different values of target plate thickness and explosives per unit length. Based on the experimental results, a numerical analysis method including the failure criteria is established. The mechanism and characteristics of using MDFs for aluminum plate cutting are identified; the possibility of using the current system as a linear separation device is verified. By utilizing a developed numerical method, the separation reliability for diverse structures and MDFs can be predicted in advance and the number of experiments required for development can be minimized.

A Study on standardization strategy based on implementation trend of smart work in small and medium-sized business (중소기업 스마트워크 추진동향 및 표준화 방향)

  • Min, J.H.;Park, J.Y.;Kang, S.G.
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2014.05a
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    • pp.734-737
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    • 2014
  • With the advent of smart age, the concern on smart work has gradually increased in the situation that creative innovation capability has become one of the important elements in business competitiveness. Most domestic small and medium-sized businesses have partly introduced smart work system due to the lack of its recognition and understanding about a specific method to implement. Under the environment, it is essential to make standardization strategy and do systematic implementation for core technology which leads global market in order to secure the dominant position in smart work related technologies. Therefore, this paper suggests standardization items which lead global standard and implementation direction on standardization through analysing the current situation introducing smart work in small and medium-sized business and technology/standardization trends.

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Optimization of feed system of base mold for washing machine using CAE (사출성형 CAE를 이용한 세탁기용 Base 성형용 금형의 유동 시스템 최적화)

  • Yoo, Min-ji;Kim, Kyung-A;Han, Seong-Ryeol
    • Design & Manufacturing
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    • v.15 no.1
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    • pp.1-7
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    • 2021
  • The position of the gate is one of the important factors for optimal injection molding. This is because inappropriate gate positions cannot fill the cavity uniformly, which can lead to defects such as contraction. In this study, CAE was performed on hot runner injection molding of the washing machine base and plasticity was compared by changing gate position from existing gate position. A total of two alternatives have been applied to compare the plasticity of the washing machine base according to its optimal gate position. The gate position of the improved molds and the gate position of the current mold is analyzed by injection molding analysis. The results of the fill time, the pressure at V/P switchover, clamping force, and deflection were compared. In washing machine base injection molding, the deflection was reduced by about 3.76% in the improved mold 2. In improved mold 1, the fill time during injection molding was reduced by 3.32% to enable uniform charging, and the clamping force was reduced by 31.24%. We have confirmed that the position of the gate can change the charging pressure and the clamping force and affect the quality and cost savings of the molded product.

Economic Complexity Index and Economic Development Level under Globalization: An Empirical Study

  • Mao, Zhuqing;An, Qinrui
    • Journal of Korea Trade
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    • v.25 no.7
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    • pp.41-55
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    • 2021
  • Purpose - This paper empirically investigates the relationship between the Economic Complexity Index (ECI) and the level of development. Moreover, this research attempts to discover the determinants of ECI in the globalization wave. Design/methodology - Our empirical model considers the relationship between ECI and the level of development in middle- and high-income economies from 1995 to 2010 by using systemic qualitative analysis, including OLS, fixed-effects, and system GMM. Next, this research used OLS regression to find the determinants of ECI. In particular, we compared the effects of different factors on ECI in the different development stages. Findings - Our main findings can be summarized as follows: 1. If the ECI increases by 1, it could lead to an increase of about 30% in the level of development in middle- and high-income economies. 2. Human capital plays an important role in the development of and increase in ECI. 3. GVC participation and outflow FDI enhance an increase in ECI, in particular in middle-income economies. 4. The development of manufacturing industries is helpful to increase ECI; however, middle-income economies should pay more attention to their comparative advantage industries. 5. R&D has positive effects on the ECI. Originality/value - To the best of our knowledge, this is the first paper that uses systemic qualitative analysis to investigate the relationship between ECI and the level of development. The paper provides suggestions for policy makers to increase ECI under the current wave of globalization, in particular in middle-income economies.

Public Policy Exception under Russian Law as a Ground for Refusing Recognition and Enforcement of Foreign Arbitral Awards

  • Andreevskikh, Liliia;Park, Eun-ok
    • Journal of Arbitration Studies
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    • v.32 no.3
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    • pp.47-70
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    • 2022
  • This paper studies legal regulation of the public policy exception in the Russian Federation and domestic judicial practice on the issue. It reviews current legislation and analyzes a number of recent court cases where an arbitral award rendered by a foreign arbitration body was refused recognition and enforcement based on public policy violation. By doing so, it contributes to the knowledge on the concept of public policy in the Russian legal system and how public policy can affect the process of recognition and enforcement of foreign arbitral awards on its territory. The review of court cases demonstrates different aspects of how the public policy exception can be applied by Russian arbitrazh courts. Such decisions can provide a clearer picture of the kinds of situation that can lead to invoking the public policy clause by the court. Also, it is of practical value as persons preparing to file a claim or to be a defendant in a Russian court can be required to present existing court decisions in support of their claim or defence.

Context Centrality in Distributions of Advertising Messages and Online Consumer Behavior

  • CHAE, Myoung-Jin
    • Journal of Distribution Science
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    • v.20 no.8
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    • pp.123-133
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    • 2022
  • Purpose: As moment-based marketing messages (i.e., messages related to current moments or event), companies put significant investments to distribute TV advertising related to external moments in a retail environment. While the literature offers strong support for the value of distributions of context-based messaging to advertisers, less attention has been given to how to design those messages to effectively communicate across channels. This research adds a new dimension of analysis to the study of advertising context and its cross-channel effects on online consumer behavior. Research Design, Data and Methodology: A system-of-equations Tobit regression model was adopted using data collected from an advertising agency that consists of 1,223 TV ads aired during the Rio Olympics and NCAA, tagging from consumers, and a text analysis. Results: First, TV ads with high centrality of context lead to lower online search behavior and higher online social actions. Second, how brands can design messages more effectively was explored by using product information as a moderator that could improve the impact of context-based TV advertisements. Conclusions: Given that expenses in traditional channels are still one of the biggest channel management decisions, it is critical to understand how consumer engagement varies by design of context-based TV advertising.