• Journal of Aerospace System Engineering
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• v.10 no.4
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• pp.84-89
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• 2016

Electronic Warfare (EW) is the mission area responsible to establish and maintain a favorable position in the electromagnetic domain. Testing and Evaluation of EW devices on modern military aircraft to pursue this critical mission area require the use of a wide range of techniques and analytical methods to assure users of the readiness of EW system to meet the challenge of a combat environment. This paper is intended as an introductory text dedicated to EW systems (especially RWR, CMDS) test and evaluation techniques and will serve experienced engineers and program managers, as well as novice engineers, as a concise reference for EW systems' test and evaluation processes and testing resources.

• Proceedings of the KWS Conference
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• 2002.10a
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• pp.439-449
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• 2002

This paper reviews our recent research works on the interconnection technologies in electronic packaging and assembly. At the aspect of advanced joining methods, laser-ultrasonic fluxless soldering technology was proposed. The characteristic of this technology is that the oxide film was removed through the vibration excitated by high frequency laser change in the molten solder droplet. Application researches of laser soldering technology on solder bumping of BGA packages were carried out. Furthermore, interfacial reaction between SnPb eutectic solder and Au/Ni/Cu pad during laser reflow was analyzed. At the aspect of soldered joints' reliability, the system for predicting and analyzing SMT solder joint shape and reliability(PSAR) has been designed. Optimization design method of soldered joints' structure was brought forward after the investigation of fatigue failure of RC chip devices and BGA packages under temperature cyclic conditions with FEM analysis and experimental study. At the aspect of solder alloy design, alloy design method based on quantum was proposed. The macroproperties such as melting point, wettability and strength were described by the electron parameters. In this way, a great deal of the experimental investigations was replaced, so as to realize the design and research of any kinds of solder alloys with low cost and high efficiency.

• 한국디지털정책학회:학술대회논문집
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• 2006.06a
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• pp.45-53
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• 2006

Ever since the computer came into being in early 20th century, rapid development of the information technology has led to the opening of the ubiquitous age where daily works can be done anywhere, anytime, and with any devices. The information technology has drawn attention from Customs around the world as a key means to fulfill multi-faced responsibilities of strengthening regional cooperation in the international trade, simplifying clearance procedures, expediting logistics flow, and ensuring security in the global supply chain. Korea Customs Service, which began the informatization effort by establishing the electronic export declaration system in 1992, completed the 100% electronic clearance system in 2000, with a number of countries now conducting benchmarking studies on the successful use of IT by KCS. This paper is to address the changes brought to the Customs administration in the information age, the progress and achievement of the Customs informatization as a proactive strategy to deal with the changing environment, and the exportation to overseas administration of the e-clearance system of KCS which strives to become the global leader of Customs informatization. The exportation. in particular, will not only lead to increased foreign currency earnings and shared know how, but also create an opportunity to reflect Korea's system in the standardization of Customs procedures around the world.

• Nuclear Engineering and Technology
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• v.52 no.8
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• pp.1764-1770
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• 2020

The present work was mainly concerned with studying the operation of RC-phase shift oscillator based on MOSFET type 2N6660 under the influence of different temperature levels ranging from room temperature (25 ℃) up-to135 ℃ and gamma-irradiation up-to 3.5 kGy. In this concern, both the static (I-V) characteristic curves of MOSFET devices and the output signal of the proposed oscillator were recorded under ascending levels of both temperature and gamma-irradiation. From which, it is clearly shown that the drain current was decreased from 0.22 A, measured at 25 ℃, down to 0.163 A, at 135 ℃. On the other hand, its value was increased up-to 0.49 A, whenever the device was exposed to gamma-rays dose of 3.5 kGy. Considering RC-phase shift oscillator, the oscillation frequency and output pk-pk voltage were decreased whenever MOSFET device exposed to gamma radiation by ratio 54.9 and 91%, respectively. While, whenever MOSFET device exposed to temperature the previously mentioned parameters were shown to be decreased by ratio 2.07 and 46.2%.

• The Journal of the Korea institute of electronic communication sciences
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• v.11 no.1
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• pp.9-16
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• 2016

Since most of devices in the IEEE 802.15.4 LR-WPAN are expected to operate on batteries, they must be designed to consume energy in a very conservative way. Two energy conservation algorithms are proposed for the LR-WPAN: DDC (Dynamic Duty Cycle) and DBT (Dynamic Beacon Tracking). The DDC algorithm adjusts duty cycle dynamically depending on channel conditions. The DBT algorithm switches beacon tracking mode on and off adaptively depending on traffic conditions. Combining the two algorithms reduces energy consumption more efficiently for a wide range of input loads, while maintaining frame delivery ratio and average delay at satisfactory levels.

• The Journal of the Korea institute of electronic communication sciences
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• v.10 no.6
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• pp.721-728
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• 2015

IOT has evolved from the internet for human oriented, therefore our life is more advanced growth smartly. IoT is the network of physical objects or things embedded with electronics, software, sensors and connectivity to enable it to achieve greater value and service by exchanging data with the manufacturer, operator or other connected devices. Until now many researches have been studied for centering keyword for detecting emerging technology of future and scientometric analysis among the papers. This paper propose searching method of emerging technology for the IOT (internet of things) and smart device which are recently interesting area via dynamic analysis for keyword mapping.

• The Journal of the Korea institute of electronic communication sciences
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• v.7 no.3
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• pp.537-543
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• 2012

Smart home System is shirt-sleeve, the automatic control systems, computer network system and network communication technology in the integration of network intelligent home control system. Intelligent household will let users have a more convenient means to management of domestic equipment, for example, through the house, wireless remote control, touch screen phone and Internet or speech recognition control household devices, more can perform scene operation, make more equipment form linkage. In this paper, we propose the intelligent household various kinds of equipment within each other can communication, do not need to user command according to different state interactive operation, thus to bring the greatest degree of user efficient and convenient, comfortable and safe.

• The Journal of the Korea institute of electronic communication sciences
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• v.12 no.4
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• pp.561-568
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• 2017

In order to effectively utilize the Coarse Wavelength Division Multiplexing(CWDM) technology in optical integrated devices, a design of a wavelength selective coupler structure between an optical fiber and an optical waveguide in a flat substrate is can be considered. In this paper, we consider the coupling between a silicon waveguide with an air trench and a single mode fiber. We investigated the tendency of coupling efficiency and its limitations according to the grating depth. For this purpose, the coupling efficiency of coupler structure designed through modeling based on coupled mode theory is predicted and quantitatively compared with simulation results using finite element method.

• The Journal of the Korea institute of electronic communication sciences
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• v.15 no.3
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• pp.473-478
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• 2020

The communication between train and it's moving environments is considered as a necessity factor to support accuracy and safety for operation of train. Communication structure and performance between sensor and train used to measure and monitor between train and it's moving environments is required in operation of the train. In this paper, railway sensor network based on LTE-R is described and analyzed for moving train to support effective measure operation and environment data from various sensor devices located through railway and then transfer the data to data control center. Finally, implementation requirement for railway sensor network is suggested.

• Journal of the Korean Ceramic Society
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• v.52 no.1
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• pp.72-76
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• 2015

150-nm-thick In-Zn-Tin-Oxide (IZTO) films were deposited by RF magnetron sputtering after a 10 to 50-nm-thick $SiO_2$ buffer layer was deposited by plasma enhanced chemical vapor deposition (PECVD) on polyethylene terephthalate (PET) substrates. The electrical, structural, and optical properties of the IZTO/$SiO_2$/PET films were analyzed with respect to the thickness of the $SiO_2$ buffer layer. The mechanical properties were outstanding at a $SiO_2$ thickness of 50 nm, with a resistivity of $1.45{\times}10^{-3}{\Omega}-cm$, carrier concentration of $8.84{\times}10^{20}/cm^3$, hall mobility of $4.88cm^2/Vs$, and average IZTO surface roughness of 12.64 nm. Also, the transmittances were higher than 80%, and the structure of the IZTO films were amorphous, regardless of the $SiO_2$ thickness. These results indicate that these films are suitable for use as a transparent conductive oxide for transparency display devices.