• The Journal of the Korea institute of electronic communication sciences
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• v.6 no.5
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• pp.629-636
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• 2011

This paper presents the design of a novel integrated T-DMB/GPS/Mobile antenna for vehicular application. The T-DMB antenna is designed with a modified meander-type microstrip patch providing linearly a polarized broadside radiation pattern. The GPS antenna is designed with an inserted slot in the patch antenna providing circularly polarized broadside radiation pattern. The Mobile (GSM, AMPS, DCS, PCS, UMTS, etc.) antenna is designed as a modified G-type patch antenna providing multi-band operation. Experimental results indicate that the impedance bandwidth (VSWR 1:2.5) of the proposed T-DMB /GPS/Mobile antenna satisfactorily matches that of the simulation results. The 2D and 3D radiation patterns and gains according to the results of the experiment are also presented and discussed.

• The Journal of the Korea institute of electronic communication sciences
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• v.5 no.5
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• pp.449-458
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• 2010

Recently, the interest on object oriented design patterns has been increased considering to reusability of software and efficiency of maintenance expense in designing software architecture. In this paper, we design the paper submission management system applicable to specific domain using domain object interface based on object oriented design patterns, and then implement it with Java and XML. The proposed system applies method of implementation by assemblying each system objects with upward after system entire architecture design by combining properly downward method and upward method and applies with GoF Design pattern. As well as, we convert domain data of system into the form of various persistent objects through XML, and minimize the complexity of system by not adopting method that generates domain object as in Class with automatic. Finally, the implementation of our system can be used in general C/S environment, but we implement system user GUI using the XSLT built in general web browser in consideration for user convenience and consistency.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.24 no.1
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• pp.55-63
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• 2013

Digital retrodirective antenna system is easy to modify and upgrade because it can control the phase information of the output signal toward opposite direction to input signal without a priori knowledge of the arrival direction. Due to this advantage, it is possible to do fast beam tracking. Especially, we need to design the digital PLL performance for the digital retrodirective array antenna system. So, in this paper the settling time of phase estimator and BER performance of retrodirective antenna system are investigated according to design of filter in digital PLL. When QAM signal is used for 1 Mbps with $30^{\circ}$ of phase delay, simulation results show that digital phase conjugation technique has better BER performance by about 1 dB than non-phase conjugation system when digital filter is stable. If not, the system can't estimate the exact phase because of oscillation of filter.

• Journal of the Korean Institute of Intelligent Systems
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• v.24 no.6
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• pp.657-664
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• 2014

In this paper, we described evaluation software that can propose rating scale and evaluate automatically on SDR(Software-Defined Radio) transmitter system. To deduct suitable rating scale, we extracted requirements based on the operating environment, operating application and operating method because SDR operating software is subordinative to the hardware. And we implementation evaluation software to automatically quality evaluation using rating scale draw from the requirements. The implemented evaluation software has automatically evaluation functions using script, can update the evaluation factor and show visual evaluation result. The implemented evaluation software is used to useful the high quality SDR operating software development.

• Journal of Internet of Things and Convergence
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• v.6 no.2
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• pp.93-100
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• 2020

Although various home services are developed as increasing the number of home devices with wire and wireless connection, privacy infringement and private information leakage are occurred by unauthorized remote connection. It is almost caused by without of device authentication and protection of transmission data. In this paper, the devices' secret value are stored in a safe memory of a smartphone. A smartphone processes device authentication. In order to prevent leakage of a device's password, a shadow password multiplied a password by the private key is stored in a device. It is proposed mutual authentication between a smartphone and a device, and session key agreement for devices using recovered passwords on SRP. The proposed protocol is resistant to eavesdropping, a reply attack, impersonation attack.

• Korean Chemical Engineering Research
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• v.53 no.3
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• pp.401-406
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• 2015

Getter is a class of materials used in absorbing gases such as hydrogen and moisture in microelectronics or semiconductor devices to operate properly. In this study, we developed a new device structure consisting of porous anodized alumina films on textured silicon wafer, which have cost efficiency in materials and processing aspects. Anodic aluminum oxide (AAO) with controlled pore sizes can be applied to a high-efficiency moisture absorber due to the high surface area and OH- saturated surface property. The moisture sorption capacity was 2.02% (RH=35%), obtained by analyzing isothermal adsorption/desorption curve.

• Management & Information Systems Review
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• v.31 no.3
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• pp.21-46
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• 2012

This paper attempts to offer an effective strategy of hedge fund based on trade probability control in the futures market. By using various technical indicators, we create an association rule and transforms it into a trading rule to be used as an investment strategy. Association rules are made by the combination of various technical indicators and the range of individual indicator value. Adjustments of trade probabilities are performed by depending on the rule combinations and it can be utilized to establish an effective investment strategy onto the risk management. In order to demonstrate the superiority of the investment strategy proposed, we analyzed a profitability using the futures index based on KOSPI200. Experiments results show that our proposed strategy could effectively manage and response the dynamics investment risks.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.37 no.1
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• pp.167-174
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• 2017

Earthwork is to level or excavate the ground to provide a space for installing structures. A large number of construction equipment such as excavators, dozers, and dump trucks are put into the earthwork operation. The equipment operators need to constantly communicate with each other during the operation. In the earthwork operation, therefore, the process should be analyzed on the equipment operation to improve the effectiveness of communication. The objective of this study is to understand the earthwork process, and improve the effectiveness of data interface by adopting the smart glass technology. In the study, the general process of earthwork is modeled using a process diagram. The data that is generated during the process is modeled using a class diagram. A database is developed to store and reuse the data. The smart glass technology is adopted to develop a data interface during the earthwork operation. The result of the prototype showed that the technology can improve the data interface during excavation overcoming the shortcomings of hand or sound signals.

• Journal of the Institute of Electronics Engineers of Korea TE
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• v.39 no.2
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• pp.6-10
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• 2002

Al films (1000~4000${\AA}$)were deposited on glass and polymer(polyethersulfine) plastic substrates by DC-magnetron sputtering for plastic-based flat-panel displays. A stepped heating process was used both to improve the electrical characteristics and to diminish the thermal expansion of the polymer substrates. Following this procedure, we could succeed in sputtering Al films without any cracking or shrinkage of the polymer substrates. The treatment temperatures and deposited process of Al films were under 200$^{\circ}C$. Also, this low temperature fabrication process allows the application of plastic substrates. Scanning Electrom Microscopy, Atomic Force Microscopy, X-ray Dffractometry, and electrical measurements such as resistivity measurements were performed to investigate the properties of deposited the Al films and their reliability. 

• Clean Technology
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• v.9 no.3
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• pp.107-113
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• 2003

Printing process generates a vast amount of toxical waste and wastewater by the development of printing and publishing industry. The regulations for various environmental pollution material, which were indispensably used in printing industries, were getting stronger. The printing industries should develop the cleaner technologies in order to avoid the regulations. In this paper, the separation characteristics of microfiltration, ultrafiltration, reverse osmosis were surveyed to make basic data for the optimization of process as cleaner technologies for printing industries. The $2kg/cm^2$ of operation pressure were suitable to the U/F System. Because of the permeate of U/F was below 3 NTU as turbidity, which was probed to be possible using the rinsing water in printing process. U/F System,