• Journal of the Institute of Electronics Engineers of Korea TC
• /
• 제41권11호
• /
• pp.67-72
• /
• 2004

In this paper, we propose a downlink beamforming method which is considered common pilot channel for coherent detection and dedicated traffic channel for desired user in FDD/CDMA systems. The existing downlink beamforming system produces phase mismatch between traffic and pilot signals at desired mobile as well as interference to other mobiles. A new downlink beamforming method can solve above problem based on least squares method between reference function and beamforming function. A numerical analysis shows that the proposed downlink beamforming method matches well and gives low BER performance.

• Journal of the Korean Chemical Society
• /
• 제44권3호
• /
• pp.249-257
• /
• 2000

This study was designed to develop learning materials of multimediafor general science instruction of high school.this learning material was made of HTML record for each middle unit according to the general science curriculum, and was included a variety of Ietter, graph, picture, drawing, animation, and other moving image materials. And it was composed five coursewares:Content, Dictionary, Science Story,lmage Material, and Questions.The learning material is uploaded an internet website under Science Education Research Institute of Kongju National University (http://science.kongju.ac.kr), and also is provided to a CD-ROM title.

• Journal of KIISE:Computer Systems and Theory
• /
• 제27권1호
• /
• pp.109-115
• /
• 2000

In this paper, we propose a new method for power estimation in nodes of multi-level combinational circuits and describe its application to the extraction of common expressions for low power design. Extracting common expressions which is accomplished mostly by the extraction of kernels and common cubes, can be transformed to the problem of rectangle covering. We describe how the newly proposed estimation method can be applied to the rectangle covering problem and show the experimental results with comparisons to the results of SIS-1.2.

• Journal of KIISE:Computer Systems and Theory
• /
• 제36권2호
• /
• pp.53-59
• /
• 2009

Simulation Based Acquisition(SBA) which pursues to use M&S in manner of integrated collaboration is being applied in defense acquisition. To accomplish SBA efficiently, reusability, reconfiguration and scalability of M&S components are important factors. To avoid constraints caused by coupling of components, PBA is designed to add and configure components easily by enabling independent interface and interaction among the components and provides common development infrastructure also. And PBA framework is implemented to support the development of a simulator which uses the PBA. It is expected that deployment of PBA framework as common development infrastructure can raise efficiency of M&S works.

• Journal of the Institute of Electronics Engineers of Korea TC
• /
• 제41권10호
• /
• pp.53-59
• /
• 2004

A new downlink beamforming method is proposed for coherent detection of Cellular systems with BPSK modulation where there exists only common pilot channel. To solve phase mismatch between traffic and pilot signals at desired mobile and to reduce interference to other mobiles, the proposed downlink beamforming method considers a cost function of signal to interference ratio criteria and gives a solution for the cost function. The computer simulation showed that the proposed method can solve the phase mismatch problem and give improved BER performance in time-varying channels.

• Journal of the Institute of Electronics Engineers of Korea SP
• /
• 제41권5호
• /
• pp.283-290
• /
• 2004

In this paper, a low-power structure for 512 tap FIR filter in MPEG audio algorithm is proposed. By using CSD(Canonic Signed Digit) form filter coefficients and maximum sharing of input signal sample, it is shown that the number of adders of proposed structure can be minimized. To minimize the number of adders, the proposed structure utilizes the 4 steps of sharing, i.e., common input sharing, linear phase symmetric filter coefficient sharing, block sharing for common input, and common sub-expression sharing. Through Verilog-HDL coding, it is shown that reduction rates in the implementation area and relative power consumption of the proposed structure are 60.3% and 93.9% respectively, comparison to those of the conventional multiplier structure.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• 제33권2호
• /
• pp.113-118
• /
• 2005

This paper shows a satellite battery cell voltage monitor system to make differential voltage measurements when one or both measurement points are beyond voltage range allowed by a conventional differential amplifier. This system is particularly useful for monitoring the individual cell voltage of series-connected cells that constitute a rechargeable satellite battery in which some cell voltages must be measured in the presence of high common mode voltage.

• Journal of Broadcast Engineering
• /
• 제5권1호
• /
• pp.130-138
• /
• 2000

The paper describes a push system, a broadcasting system in the internet, which is developed for internet and intranet use. In this paper, we carried out research on the method to support the large number of users in the intranet environment. Particularly the paper analyzes the effects on the network traffic according to the number of the user connected to the push system and the frequency of the connections when push servers are distributed over the intranet. Push system described here uses two different kinds of channels, common channel and local channel. Common channel is the channel to be replicated among the push servers in the intranet. This paper shows that the method using the common channel synchronization is efficient in supporting the large number of intranet users. We introduce an algorithm to make the interconnections between channels efficiently amongpush servers distributed over the intranet.

• Defense and Technology
• /
• 11호통권153호
• /
• pp.64-69
• /
• 1991

유도무기체계의 구동장치 관련 기술은 선진국과 뚜렷한 기술격차를 보이고 있으며, 관련 부품의 판매와 기술이전은 엄격히 통제되고 있다. 현재 유도무기 구동장치 분야의 많은기술적 문제점들은 군용 및 산업장비에서 파생되는 여러 문제점들과 상당부분에서 공통적인 면을 보이고있으며, 이러한 관점에서 볼때 산.학.연 협동의 활발한 연구가 절실히요청되고 있다

• Defense and Technology
• /
• 1호통권239호
• /
• pp.30-39
• /
• 1999

효과적인 연구개발을 위해서는 미래를 내다보는 통찰력에 바탕을 둔 강력한 정책이 뒷받침되어야 하며 동시에 관련 주체간의 공통인식과 공감대 확산이 매우 중요하다. 이러한 점에서 21세기 우리나라의 생존여부가 과학기술력에 달려있으며, 바로 국방과학기술이 불확실한 전략적 미래에 대비한 가장 확실한 담보물이다