• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.11a
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• pp.149-150
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• 2007

ONO(Oxide-Nitride-Oxide)구조는 기억소자의 전하보유 능력을 향상시키기 위해 도입된 게이트 절연막이다. 본 연구에서는 ELA(Excimer Laser Annealing)방법으로 비정질 실리콘을 결정화 시켜서 그 위에 NVM(Nonvolatile Memory)소자를 만들어 전기적 특성을 측정하여 결과를 나타내었다. 실험 결과 같은 크기의 $V_D$에서 $V_G$를 조절함으로써 $I_D$의 크기를 조절할 수 있었다. $V_G-I_D$ Graph에서는 $I_{on}$과 $I_{off}$, 그리고 Threshold Voltage를 알 수 있었다. $I_{on}/I_{off}$ Ratio는 $10^3-10^4$이다. $V_G-I_D$ Graph에서는 게이트에 인가하는 Bias의 양을 통해서 Threshold Voltage의 크기를 조절할 수 있었다. 이는 Trap되는 Charge의 양을 임의로 조절할 수 있다는 것을 의미하며, 이러한 Programming과 Erasing의 특성을 이용하여 기억소자로서의 역할을 수행하게 된다.

• Journal of Korean Society of Forest Science
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• v.102 no.3
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• pp.463-466
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• 2013

We examined relationship between rainfall and triggering of shallow landslides in South Korea, based on hourly rainfall data for 478 shallow landslides during 1963-2012. Rainfall intensity(I) and duration(D) relationship was analyzed to obtain the I-D threshold for the initiation of a shallow landslide using the quantile regression analysis. The I-D threshold equation from in this study is: $I=9.64D^{-0.27}$($4{\leq}D{\leq}76$), where I and D are expressed in millimeters per hour and hours, respectively. In addition, rainfall criteria were proposed to predict the potential to cause landslides, based on values of I-D and cumulative rainfall derived from quantile regression analysis. Our findings may provide essential data and important evidences for the improvement of landslide warning and evacuation system.

• Journal of the Korean Institute of Telematics and Electronics
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• v.21 no.4
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• pp.58-64
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• 1984

A simple model for the impurity profile in an ion-implanted channel layer of an enhancement type IGFET is assumed and a simple expression for the threshold voltage derived by using the assumed impurity profile is analyzed in detail. Also, this simple model is applied to simulating the substrate bias dependence of its threshold voltage. Excellent agreement is obtained between theory and experiment on n-channel devices. The error range of threshold voltage between gaussian-profile and box-profile is calculated in this paper and a new method of calculating the depth of ion-implanted Baler D is also introduced.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.1189-1192
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• 2009

Short channel a-Si:H TFT devices with Cu electrodes have been investigated. Short channel TFTs are defined by new plasma etch process. When the channel length becomes shorter, the TFT characteristics (threshold voltage, off current, sub threshold voltage, etc.,) are degraded. These degraded characteristics can be improved through the hydrogen plasma treatment and new gate insulator structure. Using these processes, 15.0 inch XGA LCD panel was fabricated successfully where the channel length of the TFT devices was about 2.5 micrometers.

• Journal of the Korean Geotechnical Society
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• v.30 no.12
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• pp.5-14
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• 2014

Most of slope failures have taken place between June and September in Korea, which cause a considerable damage to society. Rainfall intensity and duration are very significant triggering factors for landslide. In this paper, landslide-triggering rainfall threshold consisting of rainfall intensity-duration (I-D) was proposed. For this study, total 255 landslides were collected in landslide inventory during 1999 to 2012 from NDMI (National Disaster Management Institute), various reports, newspapers and field survey. And most of the required rainfall data were collected from KMA (Korea Meteorological Administration). The collected landslides were classified into three categories: debris flow, shallow landslide and unconfirmed. A rainfall threshold was proposed based on landslide type using statistical method such as quantile-regression method. Its validation was carried out based on 2013 landslide database. The proposed rainfall threshold was also compared with previous rainfall thresholds. The proposed landslide-triggering rainfall thresholds could be used in landslide early warning system in Korea.

• JSTS:Journal of Semiconductor Technology and Science
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• v.10 no.2
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• pp.79-99
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• 2010

Pulsed current-voltage (I-V) methods are introduced to evaluate the impact of fast transient charge trapping on the performance of high-k dielectric transistors. Several pulsed I-V measurement configurations and measurement requirements are critically reviewed. Properly configured pulsed I-V measurements are shown to be capable of extracting such device characteristics as trap-free mobility, trap-induced threshold voltage shift (${\Delta}V_t$), as well as effective fast transient trap density. The results demonstrate that the pulsed I-V measurements are an essential technique for evaluating high-$\kappa$ gate dielectric devices.

• Journal of the Korean Institute of Telematics and Electronics D
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• v.36D no.4
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• pp.77-85
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• 1999

By assuming a linearly graded depletion edge approximation in the intrinsic MOS region and by taking into account the mobility variation dependent on both lateral and vertical fields, a physics-based analytical model for a short-channel(n-channel) MOSFET is suggested. Derived expressions for the threshold voltage and the drain current of typical MOSFET is structures could be used in a unified manner for all operating range. The threshold voltage was calculated by changing following variables : channel length, drain-source voltage, source-substrate voltage, p-substrate doping level, and oxide thickness. It is shown that the threshold voltage decreases almost exponentially as the channel length decreases. In addition, the short-channel threshold voltage roll-off, the channel length modulation and the electron mobility degradation can be derived within a satisfactory accuracy.

• Proceedings of the KIEE Conference
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• 1999.07e
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• pp.2277-2279
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• 1999

We have investigated the characteristic analysis of ultrasonic in case of occurring partial discharge in experimental steel chamber. This study presents the discriminative method of partial discharge by optimum threshold value. We have carried out the experiments of measuring partial discharge numbers between ultrasonic sensor and transducer with changing distance and barrier inside steel chamber. After the measured data were trasformed A/D conversion by GPIB, we used the optimum method of threshold value for counting numbers of partial discharge.

• Journal of the Korean Institute of Telematics and Electronics D
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• v.34D no.3
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• pp.60-73
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• 1997

By introducing a compressive-strained quanternary InGaAsP quantum-wells instead of a conventional ternary InGaAs quantum-wells in 1.55.mu.m DFB-LD, the lasing performances canb e improved and the problems caused by the thickness non-uniformity and the compositional abruptness among the hetero-interpaces canb e relaxed. In this paper, we investigated an iptimum InGaAsP/InGaAsP multiple-quantum-well(MQW) structure as an active layer in a direct-modulated 1.55.mu. DFB-LD from the view point of threshold current, chirping charcteristics, and resonance frequency. The optimum compressive-strained MQW structure was revealed as InGaAsP/InGaAsP structure with strain amount of about 1.2%, number of wells $N_{w}$ of 7, well width $L_{w}$ of 58.agns.. The threshold current density J of 500A/c $m^{2}$, the linewidth enhancement factor a of 1.8, and differential resonance frequency of d $f_{r}$/d(I-I)$^{1}$2/=2GHz/(mA)$^{1}$2/(atI=2 $I_{th}$) were expected in 1.55.mu.m .gamma./4-shifted DFB-LD with the cavity length of 400.mu.m long and kL value of 1.25. These values are considerably improved ones compared to those of 1.55um DFB-LD with InGaAs/InGaAsP MQW which have enhancement factor and the resonance frequence frequency by the detuning of lasing wavelength and gain-peak wavelength. It was found that the linewidth enhancement factor of 20% and differential resonance frequency of 35% without the degradation of the threshold current density could be enhanced in the range of -15nm~-20nm detuning which can be realized by controlling the thickness and Incomposition of InGaAsP well. well.and Incomposition of InGaAsP well. well.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.10 no.7
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• pp.1222-1228
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• 2006

In this paper, I propose a video watermaking method using adaptive threshold value and half-cell motion vector. Conventional method cause a lot of change of motion vectors and bring about a falling-off in invisibility, because it search embedding condition about whole macroblocks and watermarks are embedded in arbitrary motion vectors. Proposed method improve invisibility and decrease in number of change of motion vectors, because it create threshold value by using power of motion vector(PMV), and watermarks are embedded in motion vectors which greater than threshold value. Consequently, proposed method improve invisibility with on an average 5.4 dB ~9.3dB according to video bit-stream.