• Proceedings of the SAREK Conference
• /
• 2006.06a
• /
• pp.52-57
• /
• 2006

This study investigates the distribution stability of binary nanofluids where binary mixtures such as $NH_3/H_2O$ and $H_2O/LiBr$ solution are used as a base fluid. When a little amount of certain nanosized particles is added into a basefluid, the thermal conductivity of that mixture increases greatly. Such mixtures are named 'nanofluids' where nano-particles should be distributed stably and uniformly so the distribution stability of nanoparticles in nanofluids is one of the most important factors for nanofluid application. Therefore, binary nanofluids in which binary mixtures are applied as the basefluids are considered as working fluids. The kind and the concentration of nanoparticles, and the concentration of ammonia are considered as the key parameters. The objectives of this paper are to visualize the dispersed status of particles in binary nanofluids and to find the effect of key parameters on the distribution stability in the ammonia absorption system.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.20 no.1
• /
• pp.51-61
• /
• 2010

Koinonia system is designed to fully utilize the advantage of Binary CDMA so as to guarantee QoS in wireless networks. In this paper, we propose the new network structure based on this system and refer to it as BLAN(Binary CDMA LAN). Although BLAN is similar structure to IEEE 802.11 WLAN, it will ensure the fast handover and QoS. We also propose the AKA(Authentication and Key Agreement) protocol and Reauthentication protocol to be used for communication in BLAN. These protocols are securely and efficiently designed using the user identity module to support the more powerful authentication. Hence, BLAN, including the proposed protocols, will support the high mobility and security. In conclusion, we expect that BLAN can be applied to future infrastructure on special environment, and it can be helpful showing the new network model which alternate WLAN.

• Korean Journal of Animal Reproduction
• /
• v.19 no.4
• /
• pp.283-291
• /
• 1996

Transgenic animal을 응용할 수 있는 분야에서는 이식유전자의 기능을 정확하게 규명하고 이를 바탕으로 실질적인 유전적인 개량을 이루기 위해서 이식유전자의 발현을 조절할 수 있는 정교한 system이 필요하다. 유전자의 미세주입법에 의해 transgenic animal을 생산할 수 있는데 이용되고 있는 tissue-specific promoter에 의한 이식유전자의 발현조절은 필요로 하는 시기나 양 등을 인위적으로 조절하고자 하는데 한계점을 갖고 있다. 이러한 이식유전자 발현의 문제점을 극복하기 위해 효모의 recombinase나 미생물의 repressor 단백질과 이들의 binding site인 operator sequence를 이용하여 인위적으로 이식유전자의 발현을 조절할 수 있는 system이 개발되고 있다. Cre/loxP system은 site-specific recombination에 의해 DNA sequence를 제거함으로서 이식유전자의 발현을 조절할 수 있다. 이식유전자 발현의 장소와 양을 조절하기 위해서는 미생물이 이용하고 있는 repressor와 이들의 operator sequence를 적용하여 ligand binary system이 개발되었다. Lac repressor system에서는 isopropyl-$\beta$-D-thiogalactoside (IPTG)가 이식유전자 발현을 조절할 수 있는 positive regulator로서 작용하고, tetracycline-VP16 system에서는 tetracycline이나 유사물질들이 negative regulator로서 이용할 수 있다. 이러한 binary system은 transgenic animal에서 이식유전자 발현의 장소와 시기 또한 양을 효과적으로 조절하는데 적용할 수 있는 것으로 나타났다. 따라서 기존의 binary system과 함께 새로운 regulatory system의 장점을 이용하여 보다 완벽한 이식유전자의 인위적인 조절 system을 이룩함으로서 transgenic animal technology의 실용화를 앞당길 것으로 기대된다.

• Proceedings of the KIEE Conference
• /
• 1997.07f
• /
• pp.2132-2135
• /
• 1997

A control approch for the robust position control of IM based on the binary disturbance observer is described. The conventional binary observer is used to remove the chattering problem of variable structure system. However the steady state error may be existed, because the conventioal binary observer etimates external disturbance with constant boundary layers. Thus in order to overcome this problem, the improved binary observer is proposed. By employing the proposed observer, the robustness is achived and the continuous control is realized without the chattering problem and the steady state error. The effectiveness of the proposed observer is confirmed by the computer simulation.

• Proceedings of the KIEE Conference
• /
• 1996.07a
• /
• pp.507-509
• /
• 1996

This paper is concerned with a position, control of induction motors using binary control. Due to the robustness and fast response, variable structure control is widely used for motor control field. However, the chattering phenomenon which is a drawback of VSC deteriorates the control performance and damages system components. In this paper, using binary control which has the characteristics of chattering alleviation and robust property solves this problem. The principle of binary control with inertial external loop and the design method of binary position controller are described. Also the control performance of proposed controller is confirmed by experiments.

• Proceedings of the KIEE Conference
• /
• 2003.10b
• /
• pp.83-85
• /
• 2003

This paper presents a speed control of permanent magnet synchronous motors (PMSM) using an adaptive integral binary observer without speed and position sensors. In view of composition with a main loop regulator and an auxiliary loop regulator, the binary observer has a property of the chattering alleviation in the constant boundary layer. In order to improve the steady state performance of the binary observer, the proposed adaptive integral binary observer is formed by adding extra integral dynamics to the switching hyperplane equation. The effectiveness of the proposed system is conformed by the experimental results.

• Proceedings of the KAIS Fall Conference
• /
• 2011.12b
• /
• pp.569-572
• /
• 2011

본 논문은 국내원천 기술인 Binary CDMA 기술을 소개하고 배전자동화(Distribution Automation) 시스템에 Binary CDMA 무선 기술을 어떻게 적용할지를 연구하고자 한다. 주요 연구내용은 Binary CDMA배전자동화 시스템, 배전자동화장치를 원격에서 제어하고 모니터링하기 위한 피코넷 네트워크 구성, 데이터 송수신을 위한 전송 스케줄링을 다루고자 한다. 그리고 배전자동화 시스템은 국가 전력망을 구축하는 아주 중요한 인프라이기 때문에 이를 보호하기 위한 무선 패킷의 암호화 적용방안에 대해서도 연구하고 하고자 한다.

• Journal of Astronomy and Space Sciences
• /
• v.20 no.2
• /
• pp.133-142
• /
• 2003

The contact binary system has been classified in five different types according to their physical properties. We suggest that extremely small mass ratio contact binary systems(q＜0.2) could be classified as a new type of contact binaries in addition to the classification. According to the Svechnikov & Kuznetsova (1990)'s catalogue, the spectral types of primary components of newly classified contact binaries are distributed at A type, and also the distribution of their various physical characteristics is laid at the center region dividing the early-type contact binaries from late-type contact binaries.

• Proceedings of the Korean Information Science Society Conference
• /
• 2007.10d
• /
• pp.417-421
• /
• 2007

최근 홈 네트워크에 대한 관심이 높아짐에 따라 관련 기술을 이용하여 실생활에 적용하려는 연구가 활발히 진행되고 있다. 이러한 홈 네트워크 기술들 중에 무선 통신 기술인 Binary CDMA(Code Division Multiple Access)는 2.4Ghz의 RF영역을 사용하여 데이터를 전송한다. Binary CDMA는 Bluetooth보다 전송거리가 길며, 기존의 CDMA와 비슷한 성능을 보이면서 회로가 단순하여 가격이 저렴하다는 장점이 있다. 본 논문은 이러한 Binary CDMA 기술을 기반으로 가정 내 Multi Zone/Multi Source 오디오 시스템의 설계 및 구현을 제안한다. 구현된 시스템은 신뢰성 있는 무선 홈 오디오 시스템 구축을 위해 이 논문에서 제시하고 있는 무선 오디오 시스템 기기간의 망 구성 및 초기화 메커니즘을 적용하였다.

• ETRI Journal
• /
• v.36 no.5
• /
• pp.772-782
• /
• 2014

Two-microphone binary mask speech enhancement (2mBMSE) has been of particular interest in recent literature and has shown promising results. Current 2mBMSE systems rely on spatial cues of speech and noise sources. Although these cues are helpful for directional noise sources, they lose their efficiency in diffuse noise fields. We propose a new system that is effective in both directional and diffuse noise conditions. The system exploits two features. The first determines whether a given time-frequency (T-F) unit of the input spectrum is dominated by a diffuse or directional source. A diffuse signal is certainly a noise signal, but a directional signal could correspond to a noise or speech source. The second feature discriminates between T-F units dominated by speech or directional noise signals. Speech enhancement is performed using a binary mask, calculated based on the proposed features. In both directional and diffuse noise fields, the proposed system segregates speech T-F units with hit rates above 85%. It outperforms previous solutions in terms of signal-to-noise ratio and perceptual evaluation of speech quality improvement, especially in diffuse noise conditions.