• Proceedings of the Korean Society of Computer Information Conference
• /
• 2014.01a
• /
• pp.19-21
• /
• 2014

본 논문에서는 기존의 산조가야금의 음을 합성하여 아두이노(Arduino)와 DSP(Digital Signal Processor)를 이용한 물리적 모델링 기반의 현 없는 산조 가야금을 구현한다. 아두이노는 저렴한 가격에 마이크로컨트롤러를 효율적으로 제어하며, DSP는 높은 분해능과 빠른 A/D변환 기능을 지원하여 복잡한 음 합성 연산의 빠른 처리를 만족시킨다. 또한 기존 가야금의 복잡한 연주법을 초보자도 쉽게 다루기 위해 가야금의 현을 대신해 터치 패널을 사용한다. 본 논문에서는 기본적인 I/O동작은 아두이노 MEGA 2560보드를, 음 합성의 복잡한 연산을 위해 CCSv5(Code Composer Studio) 툴과 DSP칩을 내장한 DSK5510 보드를 이용하여 기능을 검증한다. 모의실험 결과 현 없는 가야금의 합성음은 기존의 음과 매우 유사하였으며, 초보자도 쉽게 제어하고 연주가 가능한 환경을 구현하였다.

• Proceedings of the KSR Conference
• /
• 2002.10a
• /
• pp.182-187
• /
• 2002

Since most of main noise sources of the railroad vehicle are transmitted to the passenger's ear through the vibration of the panel, the insulation performance of the panels should be high enough to protect the passengers from the noisy environment. Specifically, the composite materials which are generally used for reducing the weight of the vehicle compartment have the low insulation performance, noise control actions should be taken appropriately by considering the insulation performance of the panels. In this study, the insulation performances of the inner/outer panels were evaluated and the contribution of the aluminum door was estimated compared to the composite panels. The results can furnish an indepth understanding of the insulation characteristics of the panel of railroad vehicle.

• Proceedings of the KAIS Fall Conference
• /
• 2004.06a
• /
• pp.236-239
• /
• 2004

본 논문은 ARM7TDMI 칩을 사용하여 전광판 시스템을 설계하고 자체적인 한글 입출력 처리가 가능하도록 하였다. 그리고 사용자가 원하는 표출문구의 입력, 편집을 쉽고 편리하게 할 수 있는 여러가지 형태의 입력방법에 대해 연구하였다. 기본적으로 PC에 의한 유/무선 문구입력과 PDA에 의한 유무선 문구입력이 가능하게 하였다. 또한 LINUX OS가 포팅 된 PXA255프로세서 기반의 임베디드 보드에서 Graphic Library인 QT/Embedded 2.3.7을 터치패널사용이 가능하도록 포팅 하여 원격지의 전광판에 문구를 이더넷 통신방법에 의해 쉽게 바꿀 수 있게 하였으며 인터넷상에 링크되어있는 유용한 정보를 전광판에서 실시간적으로 볼 수 있도록 하였다.

• Journal of KSNVE
• /
• v.9 no.2
• /
• pp.248-257
• /
• 1999

This paper presents the model updating of an equipment panel by using modal test and sensitivity analysis. The equipment panel is one of the major structures of communication satelite, on which broadcasting and communication equipments are mounted. For high rigidity and light weight, the panel was designed as an aluminum honeycomb sandwich panel. In addition, heat pipes were embedded in the panel for thermal control. It is essential to improve the finite element model of a spacecraft structure by using modal test in order to verify that the satellite is designed and fabricated with adequate margin under launch environment. In this paper, Young's modulus of aluminumfacesheet was selected as a modified parameter in the sensitivity analysis. The effect of boundary conditions on model improvement was also investigated.

• Korean Journal of Optics and Photonics
• /
• v.20 no.2
• /
• pp.128-133
• /
• 2009

In this paper, an optical touch panel device is newly proposed, with operating principle based on the optical coupling between a pointing pen having a built-in light source and perpendicularly crossed optical waveguide arrays. In order to enable an external light to couple into a waveguide core, the auxiliary pyramidal structures are introduced into all intersecting points located periodically along optical waveguides. The shape is optimized for minimizing the unwanted propagation loss due to the same structure by a ray tracing method. For the optical waveguide with the size of $50{\times}50{\mu}m^2$, the bottom width, height, and slope angle of the optimized pyramidal structure are $50{\mu}m$, $22.5{\mu}m$, and $42^{\circ}$, respectively. The optical coupling efficiency of about 97.8% and the average propagation loss of 0.3 dB/mm were achieved for the optimized touch panel. Finally, it is found from the tolerance analysis that tilting of the pen up to ${\pm}12^{\circ}$ can be allowed.

• Journal of Korea Port Economic Association
• /
• v.31 no.1
• /
• pp.171-188
• /
• 2015

Logistics network has been increasingly acknowledged as one of the important driving force for economic development in China. With the scope of logistics effect broadening and the development of logistics infrastructure, both logistics network and economy in terms of GDP in China has experienced rapid development hand in hand. This paper investigates the relationship between logistics network and economic growth, using a dataset covering 31 provinces over the period from 2003 to 2012 in China. Factor analysis is applied to obtain a total evaluation of logistics function defining the impact of logistics network on the national economy growth. According to fixed effect panel data approach, a significant and positive impact of logistics network on economic growth in China is found, meanwhile, a comparative analysis regarding economic development between coastal provinces and interior provinces is also conducted. The results suggest that the impact of logistics network on economic growth is higher in eastern provinces than that in western provinces. The policy implication for other nations, in particular for developing nations, is logistics network should be regarded as an important driving force for economic development, and investment should be made in advance to achieve the best efficiency in economic development and planning.

• Journal of the Institute of Electronics Engineers of Korea SD
• /
• v.49 no.1
• /
• pp.1-7
• /
• 2012

We have developed a new gate driver circuit for liquid crystal displays using oxide thin-film transistors (TFTs). In the new gate driver, negative gate bias is applied to turn off the oxide TFTs because the oxide TFT occasionally has negative threshold voltage (VT). In addition, we employed three parallel pull-down TFTs that are turned on in turns to enhance the stability. SPICE simulation showed that the proposed circuit worked successfully covering the VT range of -3 V ~ +6 V And fabrication results confirmed stable operation of the new circuit using oxide TFTs.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
• /
• 2012.04a
• /
• pp.464-467
• /
• 2012

본 연구에서는 최근 신재생에너지원으로서 가장 널리 사용되고 있는 태양광 시스템에 대하여 화재발생시 야기될 수 있는 위험성뿐만 아니라 화재진압 과정에서 발생할 수 있는 문제들을 다루었다. 특히 주택의 지붕위에 설치된 실리콘이 주성분인 태양광 패널은 화재가 발생할 경우 생성되는 열을 차단 및 반사하여 건물 내에 축적시킴으로써 화재강도를 직접적으로 증가시킬 수 있으므로 설치 시 이러한 위험성에 대비할 수 있는 방안을 마련해야 한다. 또한 PV 시스템에 연결된 고압 전력선에 물을 뿌릴 경우 소방대원들의 감전으로 인한 부상이나 사망으로 이어질 수 있으므로, 이를 방지하기 위한 대책마련이 시급한 것으로 나타났다. 해외에서는 현재 전력전자 소자가 내장되어 있는 DC 차단스위치 및 모듈이 판매되고 있는 것으로 조사되었다.

• Journal of Broadcast Engineering
• /
• v.20 no.4
• /
• pp.568-579
• /
• 2015

Recently, mobile devices with touch display panel are widely used. Accuracy and reaction speed of touch signal are very important in touch devices. Therefore, we need to develop an effective algorithm to reduce touch noise quickly and accurately. This paper proposes a touch noise reduction algorithm using Kalman filtering in consideration of signal motion. First, a specific pre-emphasis processing is applied to an input signal so as to maximize the effect of Kalman filtering. In other words, a pure signal in the touch signal increases but noise in the touch signal decreases. Next, motion of the signal is detected. Motion estimation is performed only if motion is detected. If we detect motion by using the only neighborhood of the signal, we can reduce about 75% of the computation in comparison with examining the entire area. Finally, Kalman filtering using the previous state of current signal is performed. Experimental results show that the proposed algorithm suppresses touch noise sufficiently without degradation of the pure signal

• Journal of the Institute of Electronics Engineers of Korea SD
• /
• v.44 no.9
• /
• pp.54-58
• /
• 2007

Development of high performance LTPS TFTs contributed to open up new SOP technology with various digital circuits integrated in display panels. This work introduces the current mode logic(CML) gate design method with which one can replace slow CMOS logic gates. The CML inverter exhibited small logic swing, fast response with high power consumption. But the power consumption became compatible with CMOS gates at higher clock speed. Due to small current values in CML, layout area is smaller than the CMOS counterpart even though CML uses larger number of devices. CML exhibited higher noise immunity thanks to its non-inverting and inverting outputs. Multi-input NAND/AND and NOR/OR gates were implemented by the same circuit architecture with different input confirugation. Same holds for MUX and XNOR/XOR CML gates. We concluded that the CML gates can be designed with few simple circuits and they can improve power consumption, chip area, and speed of operation.