• Proceedings of the Korean Institute of Communication Sciences Conference
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• 2004.07a
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• pp.28-28
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• 2004

• Proceedings of the KIEE Conference
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• 2000.07d
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• pp.2856-2858
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• 2000

This paper proposes a scan code method for obstacle avoidance of mobile robot. Obstacles detected in a circular window are converted to scan codes and then to the steering angle. The safe rotating radius is obtained by the scan code to avoid the collision between robot and obstacle and. the minimum distance for rotation is calculated. Effectiveness of the method is illustrated through simulations, and the results show that the proposed method can be efficiently implemented to an unknown environment.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.12 no.8
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• pp.1384-1390
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• 2008

The TCP protocol is originally designed for wired network, however it performs very poor in wireless network due to different nature of wireless network from wired networks. In terms of TCP performance improvement in wireless Ad-hoc network, many researches show that small congestion window size of TCP connection can improve TCP performance. We propose a new TCP algorithm to improve TCP performance in wireless Ad-hoc network. The basic idea of our approach is that TCP receiver estimates the optimum window size and then sets congestion window limit of TCP sender to an optimum value by using the advertised window field in TCP ACK packet. From extensive computer simulation, the proposed algorithm shows superior performance than traditional TCP protocols in terms of packet delivery ratio and packet loss.

• The Journal of the Korea institute of electronic communication sciences
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• v.5 no.4
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• pp.486-493
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• 2010

This paper demonstrates the design and implementation of fruit larder system that is able to monitor and control restoration environment using mobile equipment. Based on RFID/USN technology, it builds wireless sensor network to enhance its efficiency to fruit larder environment and inventory management and performs automated environment management through window-based application that works in desktop environment. Additionally, using WINC service, it provides remote control function for fruit larder using mobile equipment.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.13 no.6
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• pp.145-151
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• 2014

The glass used for mobile display windows is required to have high strength. Chemical strengthening by means of ion exchange is widely used glass. The depth of the layer and the compressed stress are affected by tempering temperature and time. The purpose of this study is to investigate the range of DOL and CS, which to less breakage during reliability tests such as the ball drop test, hole drop test, 3-point bending test, drop test, and tumble test with Soda-lime Glass.

• The KIPS Transactions:PartD
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• v.8D no.3
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• pp.265-272
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• 2001

In case of implementing a complicated application like WAP (Wireless Application Protocol) in a mobile terminal with the characteristics of bare machine and versatile kernel aspects of which are control, interrupt and IPC(Inter Process Communication), a special methodology should be needed. If not, it will cause more cost and human resources, even delayed product into launching for the time-to-market. This paper suggests AKL, (Abstract Kernel Layer) for the design and implementation of WAP on basis of multi-platform. AKL is running on the various kernel including REX, MS-DOS, MS-Window, UNIX and LINUX. For the purpose of it, AKL makes machine-dependant features be minimized and supports a consistent interface on API (Application Program Interface) point of view. Therefore, it makes poring times of a device be shorten and makes easy of maintenance. We validated our suggestion as a consequent of porting WAP into PlamV PDA and mobile phone with AKL.

• KSCI Review
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• v.12 no.2
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• pp.25-46
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• 2004

$\bullet$ Windows CE 5.0 $\triangleright$ 사용자 환경에 맞도록 수정/확장 $\triangleright$ 최적의 개발 생산성 제공 $\triangleright$ 네트워크/멀티미디어 기능 $\triangleright$ 안전된 운영체제 성능 $\triangleright$ Window CE 개발방법 $\triangleright$ 다양한 선택사항 $\triangleright$ 각각의 방법에 따른 장단점 $\triangleright$ 상황에 따른 방법의 결정

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.42 no.11
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• pp.49-54
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• 2005

This paper proposes the low power MDCT algorithm for precise FV with minimum size of sub-window in mobile phone. Proposed algerian uses the coefficient at the middle of whole result process requiring the least number of calculations, since it has a good characteristic when used as standard of the FV and needs minimum amount of operation. In addition, using the DCT result related to the middle frequency makes the characteristic of FV more superior because it suppresses the impulsive noise and difference of focus values is larger than any others. The proposed algorithm is implemented using Verilog HDL and verified using Excalibur-ARM board.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.12 no.6
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• pp.994-1001
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• 2001

In this paper, we propose the Improved SIR-based Power Control method in mobile communication system. Generally speaking, SIR-based design considering both channel noise and multiuser interference is accurate indication of signal quality and provides good performance. However, one serious problem associated with SIR-based Power Control is the potential of Positive Feedback which can endanger the stability of the system. Therefore from SIR definition, we decrease the signal\`s Interference we will got a improved SIR and have a stable power control Also in mobile using window register which has Up-Maintain-Down power control step size instead of Up-Down, we got a better performance. This paper assesses the performance of Improved SIR based Power Control using PIC and window register. The proposed Improved SIR based Power Control is presented and compared with existing SIR based Power Control and Strength-and-SIR based Power Control.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.9 no.6
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• pp.768-775
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• 1998

The equalizer is the central part of the receiver and its performance significantly affects the overall performance of the system in the mobile communication. A proposed equalizer is composed of the channel estimator, MLSE based on the Viterbi algorithm and GMSK decoder. The approximation of GMSK with QPSK has great impact on the equalizer design, because it allows us to use the existing simple and efficient algorithms for designing optimal QPSK equalizer. In order to estimate efficiently channel, we use a sliding window algorithm based on energy calculation and cross-correlator. And also a tuning scheme is presented in order to improve the equalizer performance. Simulation results indicate that a proposed equalizer meets the GSM standards easily in terms of performance.