• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2012.05a
• /
• pp.747-749
• /
• 2012

This paper is analyzing the SoC policy of major nations as the U.S, Japan, Europe, Taiwan, China and draw the suggestions for the development of semiconductor industry in Korea. SoC is the non-memory semiconductor to support and put into action the function of system. SoC is big market over the 200billion dollars and have a huge potential for new IT convergence market. Developed countries as the US, Japan, and Europe have enforced the industrial competitiveness by company investment and Taiwan supported the SoC Industry by government fund. Korea is No.1 superpower in DRAM semiconductor, but very weak in SoC Industry. We should secure the competitiveness of SoC Industry by the development of core technology, planning the growth policy, and building the cooperative model to leap the SoC power nation.

• Journal of IKEEE
• /
• v.13 no.2
• /
• pp.208-215
• /
• 2009

The high efficiency power management IC(PMIC) with DT-CMOS(Dynamic Threshold voltage MOSFET) switching device for portable application is proposed in this paper. Because portable applications need high output voltages and low output voltage, Boost converter and Buck converter are embedded in One-chip. PMIC is controlled with PWM control method in order to have high power efficiency at high current level. DTMOS with low on-resistance is designed to decrease conduction loss. Boost converter and Buck converter, are based on Voltage-mode PWM control circuits and low on-resistance switching device, achieved the high efficiency near 92.1% and 95%, respectively, at 100mA output current. And Step-down DC-DC converter in stand-by mode below 1mA is designed with LDO in order to achive high efficiency.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.20 no.9
• /
• pp.1641-1648
• /
• 2016

A weather radar estimates Doppler frequency and width of Doppler spectrum from the received weather signal which represents the return echoes from rain or dust particles in a corresponding area. These estimates are very important parameters since they are directly related to precipitation, wind velocity and degree of turbulence. Therefore, these estimated values should be highly reliable to obtain accurate weather information. However, the echoes of a weather radar include both the weather signal and the clutter which occurred from ground reflection or moving objects, etc. The existence of the clutter in the echoes may cause serious errors in the estimation of weather-related parameters. Therefore, in this paper, models are developed to represent the weather signal and the clutter for the purpose of analyzing estimation errors caused by the strong clutter echoes. Using these models, various return echoes according to the weather signal and clutter power are simulated to analyze the effects of the clutter.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.4 no.3
• /
• pp.705-711
• /
• 2000

A thin film oxide semiconductor micro gas sensor array which shows only 60 mW of power consumption at an operating temperature of $300^{\circ}C$ has been fabricated using microfabrication and micromachining techniques. Excellent thermal insulation of the membrane is achieved by the use of a double-layer structure of $0.1\mum\; thick\; Si_3N_4 \;and\; 1 \mum$ thick phosphosilicate glass (PSG) prepared by low-pressure chemical-vapor deposition (LPCVD) and atmospheric-pressure chemical-vapor deposition (APCVD), respectively. The sensor array consists of such thin film oxide semiconductor sensing materials as 1 wt.% Pd-doped $SnO_2,\; 6 wt.% A1_2O_3-doped\; ZnO,\; WO_3$/ and ZnO. Baseline resistances of the four sensing materials were found to be stable after the aging for three days at $300^{\circ}C$. The thin film oxide semiconductor micro gas sensor array exhibited resistance changes usable for subsequent data processing upon exposure to various gases and the sensitivity strongly depended on the sensing layer materials.

• The Journal of Information Technology
• /
• v.1 no.2
• /
• pp.143-162
• /
• 1998

As a method of providing lifelong educational opportunities to working professionals, some legal provisions allowing for the establishment and management of an entrusted education system linked with college and corporation was duly approved in 1994. According to the recent trend in the military organization, to provide higher educational opportunities to noncommissioned officers and warrant officers with the purpose of inspiring their spirit and improving military capabilities has been much increased. Professional soldiers such as noncommissioned officers and warrant officers have a lot of problems to continue their attendance at school because of regular military maneuvers, constant alert status and long-term outdoor military training. Even more serious problem is that the current curriculums and some departments in college are not concurrent with the present job specifications and the military specialties of the individual soldier as well. The purpose of this paper is, therefore, to introduce a newly revised educational model that provides more viable academic courses and curriculums to military professionals along with a proposal for the establishment and management of long distance educational system within barracks, utilizing the latest information and telecommunication technology.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.14 no.10
• /
• pp.2201-2206
• /
• 2010

The shortage of fossil fuel drives researchers to find a new way to increases energy efficiency. In this paper, we propose a method to control the direction and speed of an air conditioner using a thermal image and fuzzy controlling method, which results in the increase of energy efficiency. The thermal image is first converted into a color temperature image which represents the temperature range from $24.0^{\circ}C$ to $27.0^{\circ}C$. The temperature image is divided into 5 columns and the distribution of them is used to analyze room temperature and control an air conditioner. The proposed method was applied to 300 by 400 thermal images. When the performance of the proposed method was compared to existing systems in energy efficiency, the proposed method was better than existing methods, which is clear from experimental results.

• 한국신재생에너지학회:학술대회논문집
• /
• 2007.06a
• /
• pp.485-488
• /
• 2007

$SF_6$(sulfur hexafluoride)는 뛰어난 단열 및 아크방지능력(arc-extinguishingproperty)으로 인해, 전력용 변압기의 절연가스와 반도체${\cdot}$액정용 플라즈마 CVD로의 cleaning gas, 주물공장 covering gas 등으로 사용되고 있다. 하지만, $SF_6$의 지구온난화지수(global warming potential)는 $CO_2$대비 23,900배가 높아 기후변화에 미치는 영향이 $CO_2$보다 훨씬 크고, 대기 중 분해되지 않고 잔존하는 기간이 $CH_4$ 10년, $CO_2$ 및 CFCs는 100년으로 추정되는데 반해, $SF_6$는 3,200년으로 연간방출양이 작더라도 오랜 기간 누적되면 그 파장이 클 것으로 사료된다. 대부분의 가스 하이드레이트(고상결정상태)는 고압, 저온에서 형성가능 하지만, 불화가스에 대해서는 쉽게 결정화가 일어난다. $SF_6$는 3$^{\circ}C$, 2기압에서 고밀도 고상화가 되기 때문에 여러 기체와 흔합되어 있는 경우 $SF_6$만을 압축된 고상 결정상태를 형성, $SF_6$를 회수, 정제할 수 있으므로 불화가스 분리${\cdot}$회수에 기술적, 경제적 효과를 기대할 수 있다. 본 연구에서는 하이드레이트 촉진제로서 계면활성제(promoter) 첨가에 따른 $SF_6$ 하이드레이트 형성 및 해리과정 실험을 통해 효율적인 $SF_6$ 저감에 관한 적용기술을 연구해 보았다.

• Journal of Korea Society of Industrial Information Systems
• /
• v.17 no.7
• /
• pp.17-24
• /
• 2012

As the resources and power on Ad-hoc networks are limited, new data aggregation techniques are required for energy efficiency. The current research on data aggregation techniques is actively in progress, but existing studies don't consider the density of nodes. If nodes are densely placed in a particular area, the information which the sensor nodes placed on those areas detect can be judged as very strong association. But, the energy spent transmitting this information is a waste of energy. In this paper the densely-concentrated node area is designated as Hotspot_Zone in the multi-hop clustering environment using the AMC and a key node is selected in the area. If the request message of data aggregation is transmitted, the key node among the neighboring nodes sends its environmental information to a manager to avoid duplicate sensing information. Therefore, the life of networks can be prolonged due to this.

• Journal of the Institute of Electronics Engineers of Korea SD
• /
• v.43 no.10 s.352
• /
• pp.118-125
• /
• 2006

A new error amplifier is presented for fast transient response of DC-DC converters. The amplifier has low quiescent current to achieve high power conversion efficiency, but it can supply sufficient current during large signal operation. Two comparators detect large-signal variations, and turn on extra current supplier if necessary. The amount of extra current is well controlled, so that the system stability can be guaranteed in various operating conditions. The simulation results show that the new error amplifier achieves significant improvement in transient response than the conventional one.

• Journal of Digital Contents Society
• /
• v.18 no.7
• /
• pp.1443-1450
• /
• 2017

The purpose of this study is to develop an intelligent parking dispatching system based on LoRa network technology. During the local festival, many tourists come into the festival site simultaneously after sunset. To handle the traffic jam and parking dispatching, many traffic management staffs are engaged in the main road to guide the cars to available parking lots. Nevertheless, the traffic problems are more serious at the peak time of festival. Such parking dispatching problems are complex and real-time traffic information dependent. We used Queuing theory to predict inbound traffics and to measure parking service performance. Q-learning algorithm is used to find fastest routes and dispatch the vehicles efficiently to the available parking lots.