• Fire Science and Engineering
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• v.26 no.3
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• pp.67-72
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• 2012

Indoor fire hydrant facilities and sprinkler system applied to the initial fire suppression for buildings' interior fire are pivotal roles in extinguishing the fire in the early stage. The roof shapes of recent buildings combined with distinctive local culture and design are being constructed. Distinctive roof forms, i.e. gable roof buildings are planned and built, View point planning with the roof gardens also restricts measurement of the discharge pressure on the indoor fire hydrant, It is too narrow to gauge the water discharge pressure with deploying up to 5 water hoses. To resolve these problems improvement for the efficient management of indoor fire hydrant system and the effective early stage flame extinguishment is suggested.

• Fire Science and Engineering
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• v.17 no.3
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• pp.55-60
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• 2003

This study established analysis theory for flow characteristics prediction of the spray nozzle and predicted discharge and discharge type of the spray nozzle from numerical analysis. It could know that discharge type of the spray nozzle from prediction data determine to position of nozzle and needle, and flow characteristics prediction of the spray nozzle could know that the characteristics according to shape of nozzle and needle is decided. New model of the spray nozzle that can maximize efficiency of fire suppression from flow characteristics and prediction data of the spray nozzle is presented. The result of this study utilize to data necessary to develop new model of the spray nozzle. Also the result of this study wish to contribute to resource technology security of the spray nozzle, technique ripple effect enlargement of same kind industry and technical development activation of fire protection field etc.

• Korean Journal of English Language and Linguistics
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• v.1 no.2
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• pp.331-347
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• 2001

In this study I investigate two implicit arguments in English middles: discharged argument and event argument. I argue that in middle formation external argument is discharged and event argument is suppressed. The proposal can account for the problems with the previous studies (Williams 1981; Keyser and Reoper 1984: Roberts 1987: Fagan 1988, 1992: Chung 2000). When a middle derives from the corresponding transitive verb, the subject argument is discharged, being an implicit argument. Argument discharge is different from argument suppression in the passives and argument deletion in the ergatives. I also argue that event argument is suppressed in middle formation. Event argument suppression is supported by the following: (i) The transitive verbs are always eventive but the corresponding middles are stative, and (ii) the middles are underlyingly eventive, (iii) the middles are “adorned” by certain manner adverbials.

• Proceedings of the KIEE Conference
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• 2006.10c
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• pp.476-478
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• 2006

A prescaler is an essential building block for PLL-based frequency synthesizers and must satisfy high-speed and low-power characteristics. The design of D-flip flips used in the prescaler implementation is thus critical. In this paper a 64/65, 128/129 dual-modulus prescaler is designed using a $0.25{\mu}m$ CMOS process. In the design a new dynamic D-flip flop is employed, where glitches are minimized using discharge suppression scheme, speed is improved by making balanced propagation delay, and low power consumption is achieved by removing unnecessary discharge. The designed prescaler operates up to 2.5GHz and consumes 3.1mA at 2.5GHz operation.

• Journal of the Korean institute of surface engineering
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• v.37 no.3
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• pp.169-174
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• 2004

MgO thin films were reactively deposited using an internal inductively coupled plasma assisted sputtering method varying reactive gas ratio to get stoichiometric film composition, and bipolar dc substrate bias to suppress micro arcs. The minimum frequency required for arc suppression was about 10KHz depending on ICP power. Their crystallinity was analyzed using X-ray diffraction and surface morphology using AFM. The surface was very smooth with rms roughness less than 0.42nm. The preferred orientation of the films were changing from (200) to bulk-like characteristics as Ar: $O_2$ratio was controlled to 10 : 2. Optical emission spectroscopy revealed that there were two distinct discharge modes: a blue one and a green one, where enhanced emission from Ar and Mg were observed. This cannot simply be understood by metallic or oxide mode of reactive sputtering due to ICP coupled to magnetron discharge.

• Proceedings of the Korean Nuclear Society Conference
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• 1996.05b
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• pp.102-107
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• 1996

The blowdown transient pipe flows resulting from the actuation of the safety/relief valve (SRV) under valve opening conditions have been analyzed. The analytical model has been developed for a uniform pipe with friction through which the flow is discharged into a suppression pool in case of a sudden opening of the SRV The piping flow characteristics and dynamic loads are calculated. Effects of system pressure, pipe length and submergence depth are included.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.58 no.2
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• pp.342-348
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• 2009

This paper introduces a novel denoising algorithm for the partial-discharge(PD) signals from power apparatuses. The developed algorithm includes three kinds of specific denoising sub-algorithms. The first sub-algorithm uses the fuzzy logic which classifies the noise types in the magnitude versus phase PD pattern. This sub-algorithm is especially effective in the rejection of the noise with high and constant magnitude. The second one is the method simply removing the pulses in the phase sections below the threshold count in the count versus phase pattern. This method is effective in removing the occasional high level noise pulses. The last denoising sub-algorithm uses the grouping characteristics of PD pulses in the 3D plot of the magnitude versus phase versus cycle. This special technique can remove the periodical noise pulses with varying magnitudes, which are very difficult to be removed by other denoising methods. Each of the sub-algorithm has different characteristic and shows different quality of the noise rejection. On that account, a parameter which numerically expresses the noise possessing degree of signal, is defined and evaluated. Using the parameter and above three sub-algorithms, an adaptive complex noise rejection algorithm for the on-line PD diagnosis system is developed. Proposed algorithm shows good performances in the various real PD signals measured from the power apparatuses in the Korean plants.

• Journal of IKEEE
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• v.9 no.2 s.17
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• pp.152-160
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• 2005

A prescaler is an essential building block for PLL-based frequency synthesizers and must satisfy high-speed and low-power characteristics. The design of D-flip flips used in the prescaler implementation is thus critical. Conventional TSPC D-flip flops suffer from glitches, unbalanced propagation delay, and unnecessary charge/discharge at internal nodes in precharge phase, which results in increased power consumption. In this paper a new dynamic D-flip flop is proposed to overcome these problems. Glitches are minimized using discharge suppression scheme, speed is improved by making balanced propagation delay, and low power consumption is achieved by removing unnecessary discharge. The proposed D-flip flop is employed in designing a 128/129 dual-modulus prescaler using $0.18{\mu}m$ CMOS process parameters. The designed prescaler operates up to 5GHz while conventional one can operate up to 4.5GHz under same conditions. It consumes 0.394mW at 4GHz that is a 34% improved result compared with conventional one.

• JSTS:Journal of Semiconductor Technology and Science
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• v.14 no.1
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• pp.1-7
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• 2014

A bidirectional transient voltage suppression (TVS) diode consisting of specially designed $p^--n^{{+}+}-p^-$ multi-junctions was developed using low temperature (LT) epitaxy and fabrication processes. Its electrostatic discharge (ESD) performance was investigated using I-V, C-V, and various ESD tests including the human body model (HBM), machine model (MM) and IEC 61000-4-2 (IEC) analysis. The symmetrical structure with very sharp and uniform bidirectional multi-junctions yields good symmetrical I-V behavior over a wide range of operating temperature of 300 K-450 K and low capacitance as 6.9 pF at 1 MHz. In addition, a very thin and heavily doped $n^{{+}+}$ layer enabled I-V curves steep rise after breakdown without snapback phenomenon, then resulted in small dynamic resistance as $0.2{\Omega}$, and leakage current completely suppressed down to pA. Manufactured bidirectional TVS diodes were capable of withstanding ${\pm}4.0$ kV of MM and ${\pm}14$ kV of IEC, and exceeding ${\pm}8$ kV of HBM, while maintaining reliable I-V characteristics. Such an excellent ESD performance of low capacitance and dynamic resistance is attributed to the abruptness and very unique profiles designed very precisely in $p^--n^{{+}+}-p^-$ multi-junctions.

• Fire Science and Engineering
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• v.20 no.4 s.64
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• pp.135-142
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• 2006

The experiment applied Positive Pressure Ventilation to rapidly exhaust heat and smoke inside the construction in the fire was done. Changes of heat discharge and smoke density were measured, with the various blowing condition like a fan tilting angle to find the effect of the parameter. Experimental apparatus were with PPV and water mist system for better efficiency, and investigate the effect of heat discharge and smoke removal. In the experiment, flame temperature has decreased when PPV was applied. Smoke density, generated from fire also decreased dramatically and the efficiency showed the highest rate at $0^{\circ}$ tilting angle. In addition, combination of PPV and water mist system highly improved the efficiency of evacuation on heat and smoke density, clearly was influenced by the tilting angle.