• Journal of the Institute of Electronics Engineers of Korea SD
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• v.41 no.12
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• pp.21-26
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• 2004

In this paper, a direct method is developed to extact RF equivalent circuit of a packaged BJT without optimization. First, parasitic components of plastic package are removed from measured S-parameters using open and short package patterns. Using package do-embedded S-parameters, a direct and simple method is proposed to extract bonding wire inductance and chip pad capacitance between package lead and chip pad. The small-signal model parameters of internal BJT are next determined by Z and Y-parameter formula derived from RF equivalent circuit. The modeled S-parameters of packaged BJT agree well with measured ones, verifying the accuracy of this new extraction method.

• Journal of the Korean Institute of Intelligent Systems
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• v.15 no.2
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• pp.270-275
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• 2005

This paper presents a fuzzy model-based adaptive approach for synchronization of chaotic systems which consist of the drive and response systems. Takagi-Sugeno (T-S) fuzzy model is employed to represent the chaotic drive and response systems. Since the parameters of the drive system are assumed unknown, we design the response system that estimates the parameters of the drive system by adaptive strategy. The adaptive law is derived to estimate the unknown parameters and its stability is guaranteed by Lyapunov stability theory. In addition, the controller in the response system contains two parts: one part that can stabilize the synchronization error dynamics and the other part that estimates the unknown parameters. Numerical examples, including Doffing oscillator and Lorenz attractor, are given to demonstrate the validity of the proposed adaptive synchronization approach.

• Journal of Internet Computing and Services
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• v.15 no.6
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• pp.55-64
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• 2014

In a Web application, you can pass without restrictions special network security devices such as IPS and F/W, URL parameter, which is an important element of communication between the client and the server, is forwarded to the Web server. Parameters are modulated by an attacker requests a URL, disclose confidential information or through e-commerce, can take financial gain. Vulnerability parameter manipulation thereof cannot be able to determine whether to operate in only determined logical application, blocked with Web Application Firewall. In this paper, I will present a technique OTACUS(One-Time Access Control URL System) to complement the shortcomings of the measures existing approaches. OTACUS can be effectively blocked the modulation of the POST or GET method parameters passed to the server by preventing the exposure of the URL to the attacker by using clean URL technique simplifies complex URL that contains the parameter. Performance test results of the actual implementation OTACUS proves that it is possible to show a stable operation of less than 3% increase in the load.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.39 no.6
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• pp.696-708
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• 2002

In this paper, a novel transcoding algorithm for the Adaptive Multi Rate(AMR) and the Enhanced Variable Rate Codec(EVRC) vocoders via direct parameter transformation is proposed. In contrast to the conventional tandem transcoding algorithm, the proposed algorithm converts the parameters of one coder to the other without going through the decoding and encoding processes. The proposed algorithm consists of the parameter decoding, frame classification, mode decision, and transcoders for two frame types. The transcoders convert the parameters such as LSP, frame energy, pitch delay for the adaptive codebook, fixed codebook vector, and codebook gains. Evaluation results show that while exhibiting better computational and delay characteristics, the proposed algorithm produces equivalent speech quality to that produced by the tandem transcoding algorithm.

• Korean Journal of Clinical Pharmacy
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• v.21 no.3
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• pp.208-214
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• 2011

목적: 이 연구의 목적은 한국인 성인 환자를 대상으로 아미카신 1일 1회 요법을 시행하였을 때의 약동학적 파라미터를 평가하고, 신기능에 따른 아미카신의 약동학적 파라미터를 비교함으로써 최적의 개인화 약물요법을 설계할 수 있도록 하는 것이다. 방법: 그람 음성균 감염에 대해 1일 1회 요법으로 아미카신을 투여 받았던 353명의 한국 성인 환자를 대상으로 항정상태에서 아미카신의 농도를 2회(약물 투여 전 1시간 이내, 약물투여 종료 후 0.5~1시간 이내) 측정하였다. 각 환자의 약동학적 파라미터(분포용적, 청소율, 반감기) 및 혈중 최고 농도, 최저 농도는 환자의 나이, 체중, 신장, 성별, 혈중 크레아티닌 농도, 투여된 약물용량, 측정된 약물의 혈중농도, 감염의 종류 등을 감안하여 산출하였다. 크레아티닌 청소율에 따라 환자를 4군으로 분류하여 아미카신의 약동학적 파라미터를 비교분석하였다. 결과: 본 연구에서 아미카신 혈중 최저, 최고 농도의 평균 ${\pm}$ 표준편차는 각각 $1.14{\pm}1.95mg/L$, $26.35{\pm}9.28mg/L$이며, 청소율, 분포용적 및 반감기의 평균 ${\pm}$ 표준편차는 각각 $55.40{\pm}23.72mL/hr/kg$, $0.35{\pm}0.12L/kg$, 그리고 $5.22{\pm}3.34hrs$로 산출되었다. 크레아티닌 청소율에 따른 아미카신의 청소율, 분포용적 및 반감기의 유의한 차이가 관찰되었다. 종합적으로 아미카신의 혈중 최저 농도는 크레아티닌 청소율이 40 mL/min 미만인 경우 40 mL/min 이상인 경우에 비해 유의하게 증가하였다. 결론: 아미카신의 약동학적 파라미터들은 신기능에 따라 유의한 차이가 있으므로 최적의 치료효과를 위해서는 환자의 크레아티닌 청소율에 따른 개인화 약물요법이 필요하다.

• Science of Emotion and Sensibility
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• v.15 no.3
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• pp.345-354
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• 2012

The purpose of this study is finding alternative parameters of the HRV so as to minimize the subjective errors by STAI and BDI, could be have two types of significant correlation levels depending on normalized method. Particularly, the LF/HF presented as the quantitative physiological parameter that can reflect both state-anxiety and trait-anxiety.

• Proceedings of the Korean Information Science Society Conference
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• 2000.10b
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• pp.487-489
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• 2000

3차원 모델을 바탕으로 실루엣 에지를 찾아 디스플레이 해주는 대부분의 시스템들은 삼각 메쉬를 기반으로 한 모델 표현법을 사용하고 있다. NPR(nonphotorealistic rendering)에서 가장 초점을 두는 것은 컴퓨터로 렌더링된 결과가 사람이 그린듯한 효과를 줄 수 있느냐에 있다. 기존에 연구된 대부분의 시스템들은 사람이 그린듯한 효과를 주기 위해 물체의 표면에 대한 텍스츄어(Texture)와 어두운 정도, 그리고 스트록(Stroke)을 표면의 윤곽에 맞도록 그리는 많은 기법들을 소개해 왔다. 본 논문에서는 NPR 표현의 가장 기본이 되는 실루엣 에지 추출에 초점을 두고 추출한 실루엣 에지에 대해 파라미터화된 브러쉬 함수(Parameterized Brush Functions)를 적용하여 다양한 스타일로 디스플레이할 수 있는 기법을 제시한다.

• Journal of the Institute of Electronics and Information Engineers
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• v.52 no.5
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• pp.147-154
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• 2015

In this paper, we employed a model which defines the sensitivity according to the background luminance, so called JND (Just Noticeable Difference), and applied to the video coding. The proposed method finds out the maximum possible quantization parameter for the current unit based on the threshold of JND model and reduce the bitrate with similar perceptual quality. It selects the higher quantization parameter and reduce the bitrate when the reconstructed signal which is coded with higher quantization parameter is in a range of allowance based on the JND threshold, i.e. the signal has the similar perceptual quality compared to that is coded with the initial quantization parameter. The proposed algorithm was implemented on HM16.0, which is a reference software of the latest video coding standard HEVC (High Efficiency Video Coding) and the coding performance was evaluated. Compared to HM16.0, the proposed algorithm achieved maximum 20.21% and 6.18% of average bitrate reduction with the similar perceptual quality.

• Journal of Korean Society of Transportation
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• v.29 no.6
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• pp.97-106
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• 2011

Mode choice model is an essential element for estimating- the demand of new means of transportation in the planning stage as well as in the establishment phase. In general, current demand analysis model developed for the mode choice analysis applies common parameters of utility function in each region which causes inaccuracy in forecasting mode choice behavior. Several critical problems from using common parameters are: a common parameter set can not reflect different distribution of coefficient for travel time and travel cost by different population. Consequently, the resulting model fails to accurately explain policy variables such as travel time and travel cost. In particular, the nonlinear logit model applied to aggregation data is vulnerable to the aggregation error. The purpose of this paper is to consider the regional characteristics by adopting the parameters fitted to each area, so as to reduce prediction errors and enhance accuracy of the resulting mode choice model. In order to estimate parameter of each area, this study used Household Travel Survey Data of Metropolitan Transportation Authority. For the verification of the model, the value of time by marginal rate of substitution is evaluated and statistical test for resulting coefficients is also carried out. In order to crosscheck the applicability and reliability of the model, changes in mode choice are analyzed when Seoul subway line 9 is newly opened and the results are compared with those from the existing model developed without considering the regional characteristics.

• Applied Chemistry for Engineering
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• v.20 no.3
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• pp.346-350
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• 2009

Natural state materials contain a lot of available nutrient components. Among them, natural nutrient substances are utilized not only as the ingredient of functional foods but also as the excipients of functional cosmetics and pharmaceutic. Of these nutrient substances, solubility parameters of each components were calculated to choose the most suitable solvents for solutions. The solubility parameters for each components were composed of the dispersion contribution of the molecular attractive function, the polar contribution of the molecular attractive function and the contribution of the hydrogen bonding force. The chi parameters ($\chi_{12}$) were calculated with the information of the solubility parameter for the solute and solvent and were used as the criteria for the optimal solute-solvent pair. The optimal solvents were suggested with the numerical values of chi parameters for some amino acids.