• 한국통신학회논문지
• /
• 제24권10A호
• /
• pp.1579-1587
• /
• 1999

게이트 길이가 $0.2\mu\textrm{m}$인 P-HEMT에 대하여 드레인 바이어스 전류의 변화 및 게이트 폭에 대해 스케일링이 가능한 잡음모델을 제안하였다. 본 논문에서는 S-파라미터를 정확히 예측하기 위하여 $\tau$를 제외한 intrinsic 파라미터는 offset를 도입하여 정규화 한 후 스케일링을 하였다. 드레인 포화전류에 대한 드레인 전류의 비율과 게이트 폭을 변수로 하는 소신호 모델 파라미터의 맞춤함수를 구하였다. 또한, 잡음 파라미터를 정확히 예측하기 위하여 진성저항 잡음 온도 $\textrm{T}_{g}$, 게이트 단 전류 잡음원 등가잡음 컨덕턴스 $\textrm{G}_{ni}$, 드레인 단 전류와 게이트 폭에 거의 관계없으며 이의 평균값은 주변온도와 유사한 값으로 $\textrm{G}_{ni}$는 회로 특성에 영향을 미치지 않을 정도로 작은 값으로 추출되었다. 그러므로, $\textrm{G}_{no}$만을 잡음 모델정수로 하는 잡음모델과 $\textrm{T}_{g}$, $\textrm{G}_{ni}$, $\textrm{G}_{no}$를 잡음 모델정수로 하는 잡음모델을 측정값과 비교하여 본 결과 Gno만을 갖는 잡음모델도 측정된 잡음 파라미터와 잘 일치하였다. 따라서, 모델 정수추출이 간단한 $\textrm{G}_{no}$만을 갖는 잡음모델은 게이트 폭과 바이어스 전류에 대해 스케일링이 가능한 실용적인 잡음모델임을 확인하였다.

• 한국수산과학회지
• /
• 제42권5호
• /
• pp.494-502
• /
• 2009

A quantitative model was developed in order to estimate fishery production damage due to anthropogenically induced environmental changes. The model is described in the following equation, $Y_D=\frac{{\phi}_D}{{\phi}_G}[Y_0{\cdot}(t_p-t_0)-\frac{Y_0}{{\phi}_G}(1-e^{-{\phi}_G(t_p-t_0)})]$, where, $Y_D$ is annual amount of fishery production by nuclear power plant. ${\varphi}$ D and ${\varphi}$ G are instantaneous decreasing coefficient of fishery production by nuclear power plant and instantaneous decreasing coefficient of gross fishery production, respectively. $Y_0$ is annual mean fishery production without damages. $t_p$ is the present time, and $t_0$ is the starting time of damages. The model was applied to fishing grounds near a nuclear power plant on the east coast of Korea. Since fishery production damages have become bigger with increasing emission of thermal effluents from generators activities in the power plant, this factor has also been considered as, $\delta_{D_i}=\delta_D\({\sum}\limits_{i=0}^{n}\;W_i/W_T\)$, where, $\delta_{Di}$ is the cumulative damage rate in fishery production from generators, $\delta_D$ is the total cumulative damage rate in fishery production, $W_i$ is the emission amount of thermal effluents by generator i, and n is the number of generators in the nuclear power plant. This model can be used to conduct initial estimates of fishery production damages, before more detailed assessments are undertaken.

• Asian Pacific Journal of Cancer Prevention
• /
• 제15권13호
• /
• pp.5277-5281
• /
• 2014

Published studies have evaluated associations between the MDM2 SNP309T>G polymorphism and bladder cancer susceptibility. However, these generated inconsistent results. The aim of the present investigation was to quantify the strength of association between MDM2 SNP309T>G polymorphism and bladder cancer risk by conducting a meta-analysis. We searched PubMed and Embase for related studies that had been published in English before April 1, 2014 and associations were assessed by summarizing the odds ratios (ORs) with the corresponding 95% confidence intervals (CIs). Five case-control studies with a total of 972 cases and 1,012 controls were finally identified to be eligible for the meta-analysis. Overall, the results indicated that there was no significant association between the MDM2 SNP309T>G polymorphism and bladder cancer risk (for the allele model G vs. T: OR=1.08, 95% CI 0.85-1.36, p=0.54; for the co-dominant model GG vs. TT: OR=1.20, 95% CI 0.74-1.93, p=0.46; for the dominant model GG+GT vs. TT: OR=0.98, 95% CI 0.80-1.20, p=0.83; for the recessive model GG vs. GT+TT: OR=1.20, 95% CI 0.83-1.74, p=0.33). However, on subgroup analysis by ethnicity, significant associations were found in Caucasians in three models (for the allele model G vs. T: OR=1.41, 95% CI 1.10-1.81, p=0.006; for the co-dominant model GG vs. TT: OR=2.16, 95% CI 1.28-3.63, p=0.004; for the recessive model GG vs. GT+TT: OR=2.06, 95% CI 1.31-3.22, p=0.002). In summary, the present meta-analysis provides evidence that the genotype for the MDM2 SNP309T>G polymorphism may be associated with genetic susceptibility to bladder cancer among Caucasians.

• Journal of Periodontal and Implant Science
• /
• 제44권6호
• /
• pp.274-279
• /
• 2014

Purpose: To evaluate whether the levels of immunoglobulin G (IgG) antibody to Tanerella forsythia are associated with periodontal status. Methods: Patients with a diagnosis of chronic periodontitis were considered candidates for the study; thus 80 chronic periodontitis patients and 28 healthy persons (control group) were invited to participate in this investigation. The presence of T. forsythia was detected by polymerase chain reaction (PCR) analysis using primers designed to target the respective 16S rRNA gene sequences. Peripheral blood was collected from each subject to identify the IgG1 and IgG2 serum antibodies against T. forsythia. All microbiological and immunological laboratory processes were completed blindly, without awareness of the clinical status of the study patients or of the periodontal sites tested. Results: The bivariate analysis showed that lower mean levels of clinical attachment level (CAL) and probing depth were found in the presence of the IgG1 antibody titers against whole-cell T. forsythia; however, only the difference in CAL was statistically significant. In the presence of the IgG2 antibody titers against whole-cell T. forsythia, the periodontal parameters evaluated were higher but they did not show statistical differences, except for plaque. The unadjusted linear regression model showed that the IgG1 antibody against whole-cell T. forsythia in periodontitis patients was associated with a lower mean CAL (${\beta}=-0.654$; 95% confidence interval [CI], -1.27 to -0.28; P<0.05). This statistically significant association remained after adjusting for possible confounders (${\beta}=-0.655$; 95% CI, -1.28 to -0.29; P<0.05). On the other hand, smoking was a statistically significant risk factor in the model (${\beta}=0.704$; 95% CI, 0.24 to 1.38; P<0.05). Conclusions: Significantly lower mean levels of CAL were shown in the presence of the IgG1 antibody titers against whole-cell T. forsythia in periodontitis patients. Thus, the results of this study suggest that IgG1 antibody to T. forsythia may have been a protective factor from periodontitis in this sample.

• 사물인터넷융복합논문지
• /
• 제10권2호
• /
• pp.77-84
• /
• 2024

지난 몇 년 동안 5G와 같은 새로운 저 지연 통신 프로토콜을 기반으로 IoT 엣지가 등장하기 시작했다. 그러나, IoT 엣지는 막대한 이점에도 불구하고, 새로운 보완 위협을 초래하여 이를 해결하기 위한 새로운 보안 솔루션이 필요하다. 본 논문에서는 IoT 시스템을 보완하는 클라우드 환경기반의 IoT 엣지 아키텍처 모델을 제안한다. 제안 모델은 IoT 엣지 장치에서 추출한 네트워크 트래픽 데이터를 기계 학습에 작용하여 사전에 보안 위협을 예방한다. 또한, 제안 모델은 로컬 노드에서 보안 데이터 일부를 할당함으로써 액세스 네트워크(엣지)에서의 부하 및 보안을 보장한다. 제안 모델은 IoT 엣지 환경 중 로컬 노드에 데이터 처리 및 관리의 일부 기능을 할당함으로써 액세스 네트워크(엣지)의 부하를 더욱 줄이는 동시에 취약 부분을 안전하게 보호한다. 제안 모델은 다양한 IoT 기능을 네임 서비스로 가상화하고, 필요에 따라 하드웨어 기능과 충분한 계산 리소스를 로컬 노드에 배포한다.

• Journal of Magnetics
• /
• 제16권2호
• /
• pp.192-195
• /
• 2011

The phase transition of vortex matter from solid to liquid was studied in iron-based superconductors. Based on the traditional vortex glass theory, we have examined the magnetoresistivity data of iron-based superconductors using our extended thermal activation model: $\rho(B,T)=\rho((T-T_g(B))/(T_c(0)-T_g(B)))^{v(z-1)}$. We predict that the magnetic field-dependent area S + $S_0$ which integrates $\rho$ with T is proportional to $B^{\beta}$, where ${\beta}$ is the vortex glass transition exponent. From our calculation, the vortex glass transition exponent is 0.33, close to the exponent of area $S_0$ + S is 0.31 in $SmO_{0.9}F_{0.1}FeAs$; the exponent of area S is 0.63, which is close to the irreversibility line exponent 2/3. Both of the results show the validity of our model. In addition, our model is shown to be effective in describing irreversibility behavior in layered superconductors.

• 대한수학회지
• /
• 제43권2호
• /
• pp.357-371
• /
• 2006

Let $X\;=\;(X_t,\;t{\in}[0, T])$ be a generalized Brownian motion(gBm) determined by mean function a(t) and variance function b(t). Let $L^2({\mu})$ denote the Hilbert space of square integrable functionals of $X\;=\;(X_t - a(t),\; t {in} [0, T])$. In this paper we consider a class of nonlinear functionals of X of the form F(. + a) with $F{in}L^2({\mu})$ and discuss their analysis. Firstly, it is shown that such functionals do not enjoy, in general, the square integrability and Malliavin differentiability. Secondly, we establish regularity conditions on F for which F(.+ a) is in $L^2({\mu})$ and has its Malliavin derivative. Finally we apply these results to compute the price and the hedging portfolio of a contingent claim in our financial market model based on a gBm X.

• 한국해양공학회지
• /
• 제23권6호
• /
• pp.71-76
• /
• 2009

This paper describes a statistical analysis method for predicting a coast fishing boat's effective horsepower. The EHP estimation method for small coast fishing boats was developed, based on a statistical regression analysis of model test results in a circulating water channel. The statistical regression formula of a fishing boat's effective horsepower is determined from the regression analysis of the resistance test results for 15 actual coast fishing boats. This method was applied to the effective horsepower prediction of a G/T 4 ton class coast fishing boat. From the estimation of the effective horsepower using this regression formula and the experimental model test of the G/T 4 ton class coast fishing boat, the estimation accuracy was verified under 10 percent of the design speed. However, the effective horsepower prediction method for coast fishing boats using the regression formula will be used at the initial design and hull-form development stage.

• The Plant Pathology Journal
• /
• 제21권4호
• /
• pp.322-327
• /
• 2005

Regression models for determining infection periods of apple white rot were developed based on conidial germination and appressorium formation of Botryosphaeria dothidea. A total of 120 apple fruits were inoculated with the fungal conidial suspension and subjected to 6 temperatures and 10 wetness periods. Conidia germinated and produced appressoria, exhibiting swollen tips of germ tubes on the fruit surface. Conidial germination (G) increased with temperature (T) and wetness period (W), and was described as $G=-89.273+7.649T+7.056W-0.109T^{2}-0.085W^{2}-0.066TW(R^{2}=0.75)$. Less than 2 hr of wetness period were enough for conidia to germinate at 25 to $30^{\circ}C$. Effects of temperature and wetness period on appressorium formation (A) could be explained as $A=-1.540-2.375W+0.045W^{2}+0.213TW(R^{2}=0.77)$. The relationship between conidial germination and appressorium formation ($A_g$) was described as$A_g=0.381-0.227G+0.005G^{2}(R^{2}=0.67)$, suggesting that conidial germination may have to reach approximately $43.7\%$ to initiate appressorium formation. Using the regression equation for conidial germination and the criterion of $43.7\%$ conidial germination, an infection model was developed to determine infection periods based on temperature and wetness period. The infection model with the criterion of $43.7\%$ conidial germination was apparently more conservative than the appressorium formation model in determining possibility of apple infection. The infection model seemed sensitive to variable weather conditions, suggesting possible use of the model for timing fungicide sprays to control white rot of apples in practice.

• 산업경영시스템학회지
• /
• 제31권4호
• /
• pp.86-92
• /
• 2008

The expected busy period for the controllable M/G/1 queueing model operating under the triadic Max (N, T, D) policy is derived by using a new concept so called "the pseudo probability density function." In order to justify the proposed approaches for the triadic policy, well-known expected busy periods for the dyadic policies are recovered from the obtained result as special cases.