• KIEE International Transactions on Electrophysics and Applications
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• 제5C권3호
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• pp.131-137
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• 2005

This paper describes a new approach to the algorithm and fundamental characteristics of the device for monitoring the leakage currents flowing through zinc oxide (ZnO) surge arresters. In order to obtain a technique for a new on-line monitoring device that can be used in the deterioration diagnosis of ZnO surge arresters, the new algorithm and on-line leakage current detection device for extracting the resistive and capacitive currents using the phase shift addition method were proposed. The computer-based on-line monitoring device can sense accurately the power frequency leakage currents flowing through ZnO surge arresters. The on-line leakage current monitoring device of ZnO surge arresters proposed in this work has the high sensitivity compared to the third harmonic leakage current detection devices. As a consequence, it was found that the proposed leakage current monitoring device would be useful for forecasting the defects and degradation of ZnO surge arresters.

• JSTS:Journal of Semiconductor Technology and Science
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• 제8권2호
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• pp.128-133
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• 2008

Phase-change random access memory (PRAM) chip cell phase of amorphous state is rapidly changed to crystal state above 160 Celsius degree within several seconds during Infrared (IR) reflow. Thus, on-board programming method is considered for PRAM chip programming. We demonstrated the functional 512Mb PRAM with 90nm technology using several novel core circuits, such as metal-2 line based global row decoding scheme, PN-diode cells based BL discharge (BLDIS) scheme, and PMOS switch based column decoding scheme. The reverse-state standby current of each PRAM cell is near 10 pA range. The total leak current of 512Mb PRAM chip in standby mode on discharging state can be more than 5 mA. Thus in the proposed BLDIS control, all bitlines (BLs) are in floating state in standby mode, then in active mode, the activated BLs are discharged to low level in the early timing of the active period by the short pulse BLDIS control timing operation. In the conventional sense amplifier, the simultaneous switching activation timing operation invokes the large coupling noise between the VSAREF node and the inner amplification nodes of the sense amplifiers. The coupling noise at VSAREF degrades the sensing voltage margin of the conventional sense amplifier. The merit of the proposed sense amplifier is almost removing the coupling noise at VSAREF from sharing with other sense amplifiers.

• Journal of Applied Biological Chemistry
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• 제49권1호
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• pp.1-7
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• 2006

Differential display reverse transcription PCR (DDRT-PCR) analysis was performed on lily 'Marcopolo' bulb scale for isolation of expressed genes during bulblet formation. Cu/Zn lily-superoxide dismutase (LSOD) of 872 bp gene, with ability to scavenge reactive oxygen in stress environment, was isolated. Northern blot analysis showed expression levels of LSOD maximized 12 days after bulblet formation. Ti plasmid vectors were constructed with sense and antisense expressions of LSOD gene and transformed into potato. Southern blot analysis of transgenic potatoes revealed different copies of T-DNA were incorporated into potato genome. In transgenic potatoes, lily SOD gene was overexpressed in sense lines and not in antisense lines. In native polyacrylamide gel electrophoresis analysis, additional engineered LSOD was detected in sense overexpressed transgenic line only. Transgenic potatoes were subjected to oxidative stress, such as herbicide methyl viologen (MV). Transgenic potato lines with sense orientation exhibited increased tolerance to MV, whereas in antisense lines exhibited decreased tolerance. In vitro tuberization of transgenic potato with sense orientation was promoted, but was inhibited in transgenic potato with antisense orientation.

• Journal of Welding and Joining
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• 제18권1호
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• pp.97-103
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• 2000

Time series analysis results show the SVD is a candidate of on-line monitoring of welding penetration when the covariance matrix of a full penetration is used as a mapping function. As the reconstructed embedding vectors from the chaotic scalar time series are manipulated by the covariance matrix, the mapped tim series lie on a hyper-ellipsoid which the lengths of semi-axes are the squared eigenvalues of the covariance matrix in the case of full penetration. These visualize by two dimensional stroboscope views. The other cases like partial penetration, are different in the sense of sizes and shapes. Here we test two types of time series; the ion current and the X-ray. The ion current is better than the X-ray as an on-line monitoring signal, because the difference of the eigenvalue spectrum of the ion(between the pull penetration and partial penetration) is bigger than those of the X-ray.

• 한국농촌건축학회논문집
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• 제5권2호
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• pp.33-41
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• 2003

Through the courses of industrialization, speedy growth and pluralism. The problems about the environment- friendly structures have become very important problem. Especially, it is getting highly appear to the expectation about the environment friendly buildings in Kangwon-do where has greacefully clean environment. The guide line for Kangwon-do can be arranged to the following through the varity analysis, outside enviroment, color, construction materials, outside design etc the guide line for Kangwon-do can be arranged as to the followings. It appears to be suitable to country houses in kangwon-do that is made of timber or red-bricks with green half circled roof and give a sense of warmth and soft. but the coastal area village is appeared wave style roof with orange color and surrounded by natural building stones or a line- plastered wall making complicated.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권1호
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• pp.417-420
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• 2007

A 12k-bit SRAM has been developed for line memory of system-on-glass (SoG) with lowtemperature poly-silicon (LTPS) thin film transistor (TFT). For accurate sensing even with the large variation and mismatches in the characteristics of LTPS TFT, mismatch immune sense amplifier is developed. The SRAM shows 30ns read access time with 7V supply voltage while dissipating 4.05mW and 1.75mW for write and read operation, respectively

• 한국수학교육학회지시리즈A:수학교육
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• 제46권3호
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• pp.273-292
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• 2007

The purpose of this study was to find out how second, fourth and sixth graders understood the main contents related to spatial sense in the Seventh National Mathematics Curriculum. For this purpose, this study examined students' understanding of the main contents of congruence transformation (slide, flip, turn), mirror symmetry, cubes, congruence and symmetry. An investigation was conducted and the subjects included 483 students. The main results are as follows. First, with regards to congruence transformation, whereas students had high percentages of correct answers on questions concerning slide, they had lower percentages on questions concerning turn. Percentages of correct answers on flip questions had significant differences among the three grades. In addition, most students experienced difficulties in describing the changes of shapes. Second, students understood the fact that the right and the left of an image in a mirror are exchanged, but they had poor overall understanding of mirror symmetry. The more complicated the cubes, the lower percentages of correct answers. Third, students had a good understanding of congruences, but they had difficulties in finding out congruent figures. Lastly, they had a poor understanding of symmetry and, in particular, didn't distinguish a symmetric figure of a line from a symmetric figure of a point.

• 한국실내디자인학회논문집
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• 제17권3호
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• pp.148-155
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• 2008

The following research focuses on the formation method of digital space by organistic line extension among various digital formation methods. The paper reflects on the meaning and concept of today's digitalism which enables the application of complex organistic system on space through advanced technology. It also explores the concept of a line in topology which differs in assumptive meaning from traditional Euclidian geometry. The findings of the research are that first, digital space is not optimized, but is a tentative formation in process. A digital space encompasses characteristics such as infinity, possibility, potential, asymmetry, and the force of virtuality such characteristics are expressed through a moving surface constantly changing with direction. Second, a digital space formed by line extension is inseparable and durable since no measurement or dimension is predetermined. Furthermore, its sense of direction and flexibility gives it a feeling of a living organism. Third, a Euclidian methodology called 'NURBS' is being developed to express such a dynamic digital space; this is reflected through three elements, control point, weights, and knots to effectively reflect the characteristics of virtuality. The opportunities of digital space are infinite, and the possibilities of formation methods likewise vast.

• 한국농촌건축학회논문집
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• 제18권2호
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• pp.1-9
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• 2016

Vernacular perspectives had been ignored in the movement of modern architecture. This study's purpose was to review vernacular perspectives and to identify vernacular characteristics of earth architecture. Six representative contemporary earth architects were selected, and then their works were analyzed. Themes of vernacular architecture based of Frampton's critical regionalism were emerged. Findings were as following: 1) constructed by considering the local climate and the region's natural characteristics, 2) constructed with local materials seeking integration of structure and finishing work, 3) having tectonic form included regional characteristics, 4) creating space of various senses and expression of texture through earth modeling, 5) presenting homogeneity of sense of place between site and architecture, and 6) pursuing ecological and sustainable architecture. These characteristics of contemporary earth architecture reflect the vernacular architecture inherited continually in architectural history. Therefore, contemporary earth architecture has been in line with contemporary architecture aiming for sustainability.

• 전기학회논문지
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• 제60권6호
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• pp.1255-1260
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• 2011

In this paper, we study on the reliability of Very High-rate Power Line Communication (VH-PLC) for Smart Grid, so that the resultant data rate is over 400Mbps at a physical layer. Firstly, reviewing the research trend of the PLC, we discuss the required techniques for supporting the Smart Grid. Considering a pre-specification with the value of several parameters, we investigate a multi-carrier modulation technique to overcome limitations of higher rate transmission under power line channel environments. Then, we propose a system specification of the VH-PLC in the sense of enhancing two features. One is resolving the problem of the co-existence of the deployed high-speed PLC according to the published standardization of KS X 4600-1 in Korea. The other is getting better performance on the grid adopting the diverse element techniques, such as multi-carrier modulation, a subcarrier utilization mode, a variable rate LDPC (Low Density Parity Check) code, and a time and frequency diversity technique. Further, a simulation tool, composed of an Event-Driven simulator and a Time-Driven simulator, is developed for the purpose of verifying the system performance and continuously cross-checking the test bench signal of the proposed VH-PLC system.