• Proceedings of the Materials Research Society of Korea Conference
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• 1994.05a
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• pp.90-90
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• 1994

• Transactions of the Korean Society of Automotive Engineers
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• v.22 no.5
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• pp.126-135
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• 2014

This paper describes the development and verification of control algorithms for V2X and environmental sensor integrated intersection support and safety systems. The objective of the research is to develop core technologies for effective fusion of V2X and environmental sensors and to develop new safety function for intersection safety. One of core technologies is to achieve the improvement of GPS accuracy, and the other is to develop the algorithm of a vehicle identification which matches all data from V2X, vehicle sensors and environmental sensors to specific vehicles. A intersection optimal pass (IOP) algorithm is designed based on these core technologies. IOP recommends appropriate speed to pass the intersection in the consideration of traffic light signal and preceeding vehicle existence. Another function is developed to prevent a collision avoidance when car crash caused by traffic violation of surrounding vehicles is expected. Finally all functions are implemented and tested in three test vehicles. It is shown that IOP can support convenient and comfortable driving with recommending optimal pass speed and collision avoidance algorithm can effectively prevent collision caused by traffic sign violation of surrounding vehicles.

• Journal of Advanced Navigation Technology
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• v.22 no.3
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• pp.213-219
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• 2018

In this paper, we propose a design method and process for hardware and software of hybrid V2X communication module that supports both C-ITS communication protocol designed for vehicle environment and Legacy LTE communication technology. C-ITS is suitable for safety service applications due to its low latency characteristics, and Legacy LTE is a technology suitable for non-safety applications such as traffic information and infotainment due to high latency and high capacity. The hybrid V2X communication module supports multiple communication technologies of WAVE and LTE, in which WAVE supports multiple channels, so that it is designed to transmit road information such as LDM and positioning correction information to an autonomous vehicle in real time. The main design results presented in this paper will be applied to the implementation of future hybrid V2X communication terminals for vehicles.

• Journal of Advanced Navigation Technology
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• v.24 no.6
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• pp.521-526
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• 2020

In this paper, we propose a design method and process for hybrid V2X communication platform that combines WAVE communication and LTE-V2X communication which are C-ITS communication protocols for vehicle environments and Legacy LTE communication which is a commercial mobile communication for evaluating the autonomous platooning platform of commercial vehicles. For a safe and efficient autonomous platooning platform, an low-latency communication function based on C-ITS communication is required, and to control it, commercial communication functions such as Legacy LTE, which can be connected at all times, are required. In order to evaluate such a system, the evaluation equipment must have the same level of communication performance or higher. The main design contents presented in this paper will be applied to the implementation of hybrid V2X terminals for functional evaluation.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.18 no.1
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• pp.59-65
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• 2008

In security layer in the CDMA2000 1x EV-DO, a standard - C.S0024-a v2.0 is being accomplished under the project of 3GPP2(3rd Generation Partnership Project2). Therefore, a security device is needed to implement the security layer which is defined on the standard document for data transfer security between AT(Access Terminal) and AN(Access Network) on CDMA2000 1x EV-DO environment. This paper realizes the security layer system that can make safe and fast transfer of data between AT and AN. It could be applied to various platform environments by designing and implementing the Security Layer in the CDMA2000 1x EV-DO Security Layer to which applies C.S0024-A v2.0 of 3GPP2.

• Journal of the Chungcheong Mathematical Society
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• v.26 no.2
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• pp.323-342
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• 2013

Let $C[0,t]$ denote the function space of all real-valued continuous paths on $[0,t]$. Define $Xn:C[0,t]{\rightarrow}\mathbb{R}^{n+1}$ and $X_{n+1}:C[0,t]{\rightarrow}\mathbb{R}^{n+2}$ by $X_n(x)=(x(t_0),x(t_1),{\cdots},x(t_n))$ and $X_{n+1}(x)=(x(t_0),x(t_1),{\cdots},x(t_n),x(t_{n+1}))$, where $0=t_0$ < $t_1$ < ${\cdots}$ < $t_n$ < $t_{n+1}=t$. In the present paper, using simple formulas for the conditional expectations with the conditioning functions $X_n$ and $X_{n+1}$, we evaluate the $L_p(1{\leq}p{\leq}{\infty})$-analytic conditional Fourier-Feynman transforms and the conditional convolution products of the functions which have the form $${\int}_{L_2[0,t]}{{\exp}\{i(v,x)\}d{\sigma}(v)}{{\int}_{\mathbb{R}^r}}\;{\exp}\{i{\sum_{j=1}^{r}z_j(v_j,x)\}dp(z_1,{\cdots},z_r)$$ for $x{\in}C[0,t]$, where $\{v_1,{\cdots},v_r\}$ is an orthonormal subset of $L_2[0,t]$ and ${\sigma}$ and ${\rho}$ are the complex Borel measures of bounded variations on $L_2[0,t]$ and $\mathbb{R}^r$, respectively. We then investigate the inverse transforms of the function with their relationships and finally prove that the analytic conditional Fourier-Feynman transforms of the conditional convolution products for the functions, can be expressed in terms of the products of the conditional Fourier-Feynman transforms of each function.

• Information and Communications Magazine
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• v.34 no.6
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• pp.11-19
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• 2017

V2X(Vehicle to Everything)는 차량 간 통신(Vehicle-to-Vehicle), 차량과 인프라 간 통신(Vehicle-to-Infrastructure), 차량과 보행자 간의 통신(Vehicle-to-Pedestrians) 등 운전 중 도로 인프라 및 다른 차량과 통신하면서 교통상황 등의 정보를 교환하거나 공유하는 기술을 말한다. V2X는 IT 기술의 발달과 여러 연구기관들의 연구개발 강화로 인해 'Connected/Smart car' 나아가 완전한 자율주행차를 구현하기 위해 빠르게 진화하고 있다. 이러한 V2X 시장이 향후 10년 간 급속한 확대가 전망되면서, 국내외 통신업체와 제조업 및 산학연은 자동차와 정보통신, 에너지, 서비스 산업을 융합한 스마트자동차 산업을 신성장 동력으로 하여 기술개발에 노력을 가속화하고 있다. 이에 본고에서는 V2X 차량 통신 기술의 주요선진국 기술개발 동향과 현 수준을 알아본다.

• Electrical & Electronic Materials
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• v.10 no.7
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• pp.692-699
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• 1997

The silicon doped $Al_{0.33}$G $a_{0.67}$As were grown by molecular beam epitaxy. The electroreflectance(ER) spectra of Schottky barrier Au/n-Al/suu x/G $a_{1-x}$ As have been measured at various modulation voltage( $V_{ac}$ ) and dc bias voltage( $V_{bias}$). From the observed Franz-Keldysh oscillations(FKO) peak, the band gap energy of the $Al_{x}$G $a_{1-x}$ As is 1.91 eV which corresponds to an Al composition of 33%. The internal electric field( $E_{i}$)of this sample is 2.96$\times$10$^{5}$ V/cm. As the modulation voltage( $V_{ac}$ ) is changed, the line shape of ER signal does not change but its amplitude varies linearly. The amplitude as a function of modulation voltage has saturated at 0.8 V. The internal electric field has decreased from 6.47$\times$10$^{5}$ V/cm to 2.00$\times$10$^{5}$ V/cm as the dc bias voltage( $V_{bias}$) increases from -3.5 V to +0.8 V. The values of built-in voltage( $V_{bi}$ ) and carrier concentration(N) determined from the plot of $V_{bias}$ from the plot of $V_{bias}$ versus $E_{i}$$^{2}$ are 0.855 V and 3.83$\times$10$^{17}$ c $m^{-3}$ , respectively.ively.y.y.y.

• The Pure and Applied Mathematics
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• v.4 no.2
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• pp.115-119
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• 1997

We show that if $f_{i}$:$X_{i}$ longrightarrow Y is strongly continuous(resp. weakly continuous, set connected, compact, feebly continuous, almost-continuous, strongly $\theta$-continuous, $\theta$-continuous, g-continuous, V-map), then F : $X_1 \bigoplus X_2$longrightarrow Y is strongly continuous(resp.weakly continuous, set connected, compact, feebly continuous, almost-continuous, strongly $\theta$-continuous, $\theta$-continuous, g-continuous, V-map).

• Journal of the Korean Wood Science and Technology
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• v.8 no.1
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• pp.22-27
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• 1980

Quantitative assessment of edge blunting of saw-teeth was carried out by TALYSURF. 1. Using the following equation, the real shape of a saw-tooth can be traced on the graph of TALYSURF. ${\frac{{\Delta}h}{h}}={\frac{V{\Delta}_x}{V_x}}$ {${\Delta}h$: vertical distance of stylus h: vertical distance in chart $V{\Delta}_x$: Velocity of stylus $V_x$: velocity of chart} 2. As shown on Fig 2, the error from stylus itself can be calculated by following equation. i) 13.8${\mu}{\leqq}$x<20.4${\mu}$ y=-0.2246x+4.59${\mu}$ ii) 0${\leqq}$x<13.8${\mu}$ y=${\sqrt{(-18{\mu})^2-x^2}}-1.42x+32.7{\mu}}$ 3. The relationship between profile of saw-tooth and error from stylus itself can be calculated by following equation. $E(%)=\frac{f(r){\times}{\frac{4}{18{\mu}}}}{f(R){\times}{\frac{R}{18.5{\mu}}}-f(r){\times}{\frac{r}{18{\mu}}}}{\times}100$ {E(%)${\frac{error\;of\;stylus}{dullness\;of\;saw\;tooth}}{\times}100$ r: radius of stylus tip R: radius of tip which is drawn in graph of talysurf f(r) : error of stylus f(R) : dullness of tip which is drawn in graph of talysurf} 4. The graph of maximum error and profile of saw-tooth was parabola.