• ETRI Journal
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• v.45 no.4
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• pp.581-593
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• 2023

This paper proposes four-ring slot resonator-based MIMO antennas of 75×150 mm² without and with CSRR structures in the sub-6-GHz range. These orthogonal-fed antennas have shown diverse characteristics with dual polarization. L-shaped parasitic structures have increased the isolation (i.e., >40 dB) in the single-element antenna over the band of 3.4 GHz-3.8 GHz. A set of three CSRR structures in the MIMO antenna reduced the coupling between antenna ports placed in an inline arrangement and enhanced the isolation from 12 dB to 20 dB and the diversity characteristics. The S-parameters of both MIMO antennas are measured and used to evaluate MIMO parameters like ECC, TARC, MEG, and channel capacity loss. The simulation results show the variations in the gain and directivity on exciting linear and dual polarizations. The diversity performance of the reported MIMO antennas is suitable for 5G applications.

• Journal of Aerospace System Engineering
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• v.4 no.2
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• pp.32-37
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• 2010

Use of wireless portable devices, like mobile phones, PDAs and Laptops is explosively increasing. Used in the aircraft, these PEDs can introduce EMI problem to aircraft Com/Nav systems. This paper addresses some foreign research result on interference caused by PEDs which are used onboard and policy of Japan and USA to limit use of PED on board.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.296-296
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• 2000

This paper describes the features of a transmission line and a wiring, and a design rule based on a demanded condition for a wiring. Like as the simulation of a circuit, by tracking the wiring path among parts that are disposed on PCB, we analyze the feature of the corresponding wiring using the design formula and rule. We implement a signal integrity simulator, which is capable of electrical and electronic simulation for the feature of a wiring signal and the corresponding signal, and the results are demonstrated.

• Asia pacific journal of information systems
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• v.11 no.3
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• pp.91-104
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• 2001

Like other communication networks, the Internet is establishing and reinforcing connections between market participants. By adapting to these networks, market participants are able to obtain the power of network to create new benefits in on-line markets. In this paper, we develop three stage non-cooperative game models to analyze the community related business market in electronic commerce where network externalities are present. It is found that, regardless of its market share, individual firm in a market tends to favor a community network. The analysis also shows there exist some possibilities that these community networks can trap the market in an inferior state when better alternatives are available to yield greater social welfare.

• Journal of the Korean Society of Marine Environment & Safety
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• v.7 no.3
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• pp.85-92
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• 2001

Ship handling simulator has much merit to provide trainees with real-like circumstances in doing virtual education and training. To improve the quality of the education, it should be included both the mathematical model which can explain complicated ship's manoeuvrability and graphic tools for 3D images which can embody the visual scenes of reality on screen. This paper is focused on how to construct the marine environment DB(data Base) using S-57 data of ENC(Electronic Navigational Chart).

• Transactions on Electrical and Electronic Materials
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• v.16 no.1
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• pp.42-45
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• 2015

The ability to take electrocardiographic measurements while performing our daily activities has become the people-choice for modern age vital sign sensing. Currently, wet and dry ECG electrodes are known to pose threats like inflammations, allergic reactions, and metal poisoning due to their direct skin interaction. Therefore, the main goal in this work is to implement a very small ECG sensor system with a capacitive coupling, which is able to detect electrical signals of heart at a distance without the conductive gel. The aim of this paper is to design, implement, and characterize the contactless ECG electrodes. Under a careful consideration of factors that affect a capacitive electrode functional integrity, several different sizes of ECG electrodes were designed and tested with a pilot ECG device. A very small cotton-insulated copper tape electrode ($2.324cm^2$) was finally attained that could detect and measure bioelectric signal at about 500 um of distance from the subject's chest.

• The Journal of the Korea Contents Association
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• v.4 no.3
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• pp.13-19
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• 2004

Because XML is a W3C standard and has characteristics like platform independent, it has a critical role in electronic commerce. Many electronic commerce systems are already using XML. Business rules and procedures should be standardized for efficient B2B electronic commerce. But a lot of companies have its own XML documents instead of standard documents. In this paper an XML message processor is designed. Clients may request services in XML and server returns response in XML in this system. This XML message processor can be applied easily and used efficiently in electronic commerce systems.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.45 no.1
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• pp.14-19
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• 2008

Semiconductor testing area challenges many testing issues due to the minimization and ultra high performance of current semiconductors. Among these issues, signal integrity test on interconnections must be solved for highly integrated circuits like SoC. In this paper, we propose an effective pattern application method for signal integrity test on interconnects. Proposed method can be applied by using boundary scan architecture and very efficient test can be preceded with pretty short test time.

• The Journal of Korea Robotics Society
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• v.12 no.1
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• pp.55-64
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• 2017

This paper proposes combination of a cognitive agent architecture named Soar (State, operator, and result) and ROS (Robot Operating System), which can be a basic framework for a robot agent to interact and cope with its environment more intelligently and appropriately. The proposed Soar-ROS human-robot interaction (HRI) agent understands a set of human's commands by voice recognition and chooses to properly react to the command according to the symbol detected by image recognition, implemented on a humanoid robot. The robotic agent is allowed to refuse to follow an inappropriate command like "go" after it has seen the symbol 'X' which represents that an abnormal or immoral situation has occurred. This simple but meaningful HRI task is successfully experimented on the proposed Soar-ROS platform with a small humanoid robot, which implies that extending the present hybrid platform to artificial moral agent is possible.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.06a
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• pp.342-343
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• 2009

Paper factories use a large amount of water and same amount of wastewater is generated. It is important to purity and recycle the wastewater because of water shortages and water pollution. The existing water treatment facilities like precipitation process need large-scale equipment and wide space to purity the wastewater of paper factory. High gradient magnetic separation (HGMS) system has the merits to purity rapidly because of large voids at filter and to occupy small space. In this paper, two types of superconducting magnets were used for HGMS systems. Cryo-cooled Bi-2223 superconducting magnet system with 70 mm room temperature bore and 200 mm of height was prepared. Cryo-cooled Nb-Ti superconducting magnet with 100 mm room temperature bore and 600 mm of height was used for magnetic separator. Magnetic filters were designed by the analysis of magnetic field distribution at superconducting magnets. The various magnetic seeding reactions were investigated to increase the reactivity of coagulation. The effects of magnetic separation of wastewater were investigated as variation of magnetic field strength and flow rate of wastewater.