• Smart Structures and Systems
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• v.4 no.2
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• pp.261-278
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• 2008

The results of the application of shape memory alloy (SMA) prestressing devices on an aqueduct are presented in this paper. The aqueduct was built in 1747 to provide water to the city of Larnaca and to its port. Because of its importance to the cultural heritage of Cyprus, the aqueduct has been selected as one of the case-study monuments in the project Wide-Range Non-Intrusive devices toward Conservation of Historical Monuments in the Mediterranean Area (WIND-CHIME). The Department of Antiquities of Cyprus, acting in a pioneering way, have given their permission to apply the devices in order to investigate their effectiveness in providing protection to the monument against probable catastrophic effects of earthquake excitation. The dynamic characteristics of the structure were determined in two separate occasions and computational models were developed that matched very closely the dynamic characteristics of the structure. In this paper the experimental setup and the measured changes in the dynamic characteristics of the monument after the application of the SMA devices are described.

• Journal of Chest Surgery
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• v.21 no.2
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• pp.203-210
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• 1988

The clinical experience with the activated clotting time[A.C.T.] for the control of heparin and protamine therapy during cardiopulmonary bypass in 40 patients between April, 1987 and September, 1987 is reviewed retrospectively. All of patients used with cold blood potassium cardioplegia for myocardial protection under standard cardiopulmonary bypass, priming and perfusate techniques respectively. This study was divided into 2 groups of patients followed by cardiopulmonary bypass time. Twenty patients, within 60 minutes of cardiopulmonary bypass time[group A] were compared with twenty patients, from 60 to 120 minutes of cardiopulmonary bypass time[group B]. Using blood cardioplegia for myocardial protection, Author observed wide variation of A.C.T. in individual response to initial heparinization[2mg /kg] and no requirement of additional heparin during cardiopulmonary bypass until 120 minutes. Total heparin amount during cardiopulmonary bypass was not related to body weight and body surface area in the both groups. After cardiopulmonary bypass, amounts of protamine for neutralization of heparin were more required in group B.

• Journal of Korean Society for Atmospheric Environment
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• v.33 no.2
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• pp.139-158
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• 2017

CMAQ (Community Multiscale Air Quality Model) simulations were carried out to estimate the potential range of contributions on surface $PM_{2.5}$ concentrations over the Seoul Metropolitan Area (SMA) with the gaseous precursors and Primary Particulate Matters(PPM) available from a recent national emissions inventory. In detail, on top of a base simulation utilizing the 2013 Clean Air Policy Supporting System (CAPSS) emission inventory, a set of Brute Force Method (BFM) simulations after reducing anthropogenic $NO_x$, $SO_2$, $NH_3$, VOCs, and PPM emissions released from area, mobile, and point sources in SMA by 50% were performed in turn. Modeling results show that zero-out contributions(ZOC) of $NH_3$ and PPM emissions from SMA are as high as $4{\sim}5{\mu}g/m^3$ over the region during the modeling period. On the contrary, ZOC of local $NO_x$ and $SO_2$ emissions to SMA $PM_{2.5}$ are less than $1{\mu}g/m^3$. Moreover, model analyses indicate that a wintertime $NO_x$ reduction at least up to 50% increases SMA $PM_{2.5}$ concentrations, probably due to increased HNO3 formation and conversion to aerosols under more abundant ozone and radical conditions after the $NO_x$ reduction. However, a nation-wide $NO_x$ reduction decreased SMA $PM_{2.5}$ concentrations even during winter, which implies that nation-wide reductions would be more effective to curtail SMA $PM_{2.5}$ concentrations than localized efforts.

• Journal of Electrical Engineering and Technology
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• v.6 no.4
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• pp.439-446
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• 2011

Frequency is an important operating parameter for the protection, control, and stability of a power system. Thus, it must be maintained very close to its nominal frequency. Due to the sudden change in generation and loads or faults in a power system, however, frequency deviates from its nominal value. An accurate monitoring of the power frequency is essential for optimum operation and prevention of wide area blackout. Most conventional frequency estimation schemes are based on the DFT filter. In these schemes, the gain error could cause defects when the frequency deviates from the nominal value. We present an advanced frequency estimation technique using gain compensation to enhance the DFT filter-based technique. The proposed technique can reduce the gain error caused when the frequency deviates from the nominal value. Simulation studies are performed using both the data from EMTP-RV software and the user-defined arbitrary signals to demonstrate the effectiveness of the proposed algorithm. Results show that the proposed algorithm achieves good performance under both steady state tests and dynamic conditions.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.59 no.3
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• pp.253-257
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• 2010

The frequency is an important operation parameter for the control, protection, and stability of a power system. The frequency as a key index of power quality can be indicative of system abnormal conditions and disturbances. Due to the sudden change in generation and loads or faults in power system, the frequency is supposed to deviate from its nominal value. It is essential that the frequency must be maintained very close to its nominal frequency. An accurate monitoring of the power frequency is essential to optimal operation and prevention for wide area blackout. As most conventional frequency estimation schemes are based on DFT filter, it has been pointed out that the gain error could cause defects when the frequency is deviated from nominal value. This paper presents an advanced frequency estimation technique using gain compensation to improve the performance of DFT filter based techniques. To evaluate performance of the proposed algorithm, the 765kV T/L system in Korea is simulated by EMTP-RV software. The proposed technique can reduce the gain error caused when the power system frequency deviates from nominal value.

• Architectural research
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• v.9 no.1
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• pp.1-8
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• 2007

These days the copyright plays a significant role in various fields of creative works and it has expanded dramatically into unprecedented ways. In Korea, architectural works copyright cases are rare due to the lack of information and understanding of the architectural works copyright. Architectural works copyright can promote architects' creative activities and enhance the quality of architectural works as art. Nevertheless, there is little effort to advance the studies of architectural works copyright in the architectural design area. Under these circumstances, this research attempts to share the basic case laws and remedies for various architectural works copyright issues in the U.S. cases. This Article examines the Thomas Shine v. David M. Childs and Skidmore Owings & Merrill, LLP Case which is the most recent case as I could reach. This case is about a story between two architects, one is from a very prestigious architectural design firm and the other, once Yale Architectural student, now practices his design work as an up-and-coming architect. A close examination of this case will provide a legal and architectural spectrum of copyright. That is, it will make it more specific how to solve the copyright infringement. Artistic and technological contexts are overlapped in Architectural works copyright as its inherent characteristics. Therefore, different ways from other copyrighted works are needed to access the untangled equations of the architectural works copyright protection. In addition, more comprehensible and specific regulations that can impose a remedy more suited to the architectural works copyright violations are needed and they should enable architects to fulfill their architectural activities under wide range of copyright protection. Moreover, in prior to all efforts to handle those equations, fundamental knowledge of architectural works copyright is required to improve the copyright protection in the architectural design area as well as to provide for the globalizing design practice. Ultimately, all of these efforts will be rewarded when constant researches based on Korean and other countries' architectural copyright cases can support them and it would be great if this research can set the stage for resolving expected copyright conflicts within the architectural design area.

• Journal of IKEEE
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• v.22 no.4
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• pp.1202-1205
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• 2018

In this paper, we proposed ggNMOS based on 4H-SiC material and analyzed its electrical characteristics. 4H-SiC is a wide band-gap meterial, which is superior in area contrast and high voltage characteristics to Si material, and is attracting attention in the power semiconductor field. The proposed device has high robustness and strong snapback characteristics. The process consisted of SiC process and electrical characteristics were analyzed by TLP measurement equipment.

• The Korean Journal of Community Living Science
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• v.14 no.3
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• pp.13-19
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• 2003

The purpose of this study was to investigate the UVA radiation protection effects of summer hats currently on the market with the purpose of making it possible to choose a hat with suitable UVA protection. Twelve different summer hats from the market were selected for the experiment. The results are summarized as follows: It is more effective to wear a hat than not wear a hat to block UVA radiation. Summer hats with the greatest degree of protection, from highest to lowest, are cotton, straw2, and straw1. In the area of the forehead, which is rarely influenced by the irradiation angle, the cotton hat was the most effective in protecting from UVA radiation because the material density was greater than that of the straw hats. A hat with a 8.5 cm brim was more effective at blocking UVA radiation on the jaw than 6 cm, 4 cm, and 0 cm wide brims, but it still couldn't block the radiation completely. Irradiation amounts at 11:00 AM on the forehead, jaw! s and left and right cheeks were lower than amounts measured on the back of the neck. This revealed that irradiation amounts depend on the shape of the hat and time of day. A hat with a brim encircling the head was found to be more effective in blocking UVA radiation than a hat with only a front or side brim.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.55 no.1
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• pp.31-34
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• 2006

A infrared rays sensor or ultrasonic sensor can detect the object at the narrow area, however a pressure sensor can detect man and animal at the wide area. It is necessary to manufacture the sensor by using Pb-free ceramics in the respect of environmental protection. Piezoelectric properties of ceramics added 0.2wt% $La_2O_3\;into\;0.96Bi_{0.5}(Na_{0.84}K_{0.16})_{0.5}+0.04SrTiO_3$ were 0.4 of kp, $31{\times}$10^{-3}Vm/N\;of\;g_{33}$. The output voltage of the pressure sensor is 0.48 V at 20 in$H_2O$. The output voltage of the pressure sensor with driving circuit is 9.8 V, 37 ms width.

• Fire Science and Engineering
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• v.24 no.2
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• pp.126-132
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• 2010

The Housing Performance Rating System, enacted on 9 January 2006, an active measure containing provisions on improved quality and advanced performance of the Fire-Protection System for equalized ability to secure safety of life to some extent, is a desirable policy in fire-safety regard. The study of theoretical background of each performance rating section for the purpose of active and wide application of The Fire-Protection System category of the Housing Performance Rating System currently in effect internally. In accordance with the result of the study, the reform measures for the currently detailed evaluation criteria have been suggested to improve the performance of the Fire-Protection area of The Housing Performance Rating System currently being in force based on the assumption of prior settlement of the following; upward settlement of the point distribution standards on the performance ratings of each head backed up by an institutional Government policy with overriding priority; and urgently enacted Fire-Protection related laws and regulations.