• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.20 no.2
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• pp.97-102
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• 2020

This paper relates with the Hybrid-SE-MMA (Signed-Error MMA) that is possible to improving the equalization performance by using the adaptive modulus and adaptive step size in SE-MMA adaptive equalizer for the minimizing the intersymbol interference. The equalizer tap coefficient is updatted use the error signal in MMA algorithm for adaptive equalizer. But the sign of error signal is used for the simplification of arithmetic operation in SE-MMA algorithm in order to updating the coefficient. By this simplification, we get the fast convergence speed and the reduce the algorithm processing speed, but not in the equalization performance. In this paper, it is possible to improve the equalization performance by computer simulation applying the adaptive modulus to the SE-MMA which is proposional to the power of equalizer output signal. In order to compare the improved equalization performance compared to the present SE-MMA, the recovered signal constellation that is the output of the equalizer, residual isi, MD(maximum distortion), MSE and the SER perfomance that means the robustness to the external noise were used. As a result of computer simulation, the Hybrid-SE-MMA improve equalization performance in the residual isi and MD, MSE, SER than the SE-MMA.

• Journal of Satellite, Information and Communications
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• v.10 no.2
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• pp.30-33
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• 2015

In this paper, we proceeded a study on the Hybrid RF based development of the smart phone Application skin disease monitoring using CMOS camera. we proposed an image transfer technology which can use the CMOS camera and we developed the smart phone application which can be possible to use a remote monitoring for skin disease. Image transfer technology using Hybrid RF communication applied for WiFi using CMOS camera. We implemented the function which can use a remote monitoring using Wi-Fi. These suggestion can be a good example for endoscopic applications using hybrid RF based smart phone application of skin disease monitoring using CMOS camera.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.10 no.6
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• pp.879-888
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• 1999

A Study on the ARQ scheme of data error control is important for more reliable information transmission. Since performance difference is large by the long transmission delay time in satellite communication, the performances of SR ARQ and conventional type-I hybrid ARQ with fixed code rate are investigated by using the parameters of packet length, channel capacity, BER, and transmission delay time especially. BCH code is used in type-I hybrid ARQ for FEC method. This paper presents the throughput analyses according to such various parameters as BCH code rate, window size, data rate and round-trip delay time. Especially we derive a performance equation of type-I hybrid ARQ with the factor of the transmission delay time using the equation of SAW ARQ. Also, the performance of type-I hybrid ARQ specially considering transmission delay time is analyzed through numerical analysis and computer simulation so we can get a important characteristics variation.

• The Journal of the Korea institute of electronic communication sciences
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• v.7 no.5
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• pp.1173-1180
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• 2012

Based on Smart Phone, this study added and implemented the mobile App to the existing IT agriculture system, which system automatically controlled green house's growth environment. Because the mobile App characterfully possesses high portability, limited resource, mobile wireless network support, enterprise mobile computing support, etc., the hybrid-App should be inevitably adopted. The hybrid App can minimize resource consumption for performing related duties and also, in spite of the mobile device's limits, it can derive high performance, in which facts the system can ensure the service-based architecture's reliance and also, implements the highly sophisticated functionality as well. Through the proposed system, the study expects to contribute to improve quality of life as well as to increase farmer's income through IT-based agriculture system development.

• Journal of Power Electronics
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• v.14 no.6
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• pp.1345-1356
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• 2014

The thermal behavior of power modules is an important criterion for the design of cooling systems and optimum thermal structure of these modules. An important consideration for high power and high frequency design is the spacing between semiconductor devices, substrate structure and influence of the boundary condition in the case. This study focuses on the thermal behavior of hybrid power modules to establish a simplified method that allows temperature estimation in different module components without decapsulation. This study resulted in a correction of the junction temperature values estimated from the transient thermal impedance of each component operating alone. The corrections depend on mutual thermal coupling between different chips of the hybrid structure. A new experimental technique for thermal mutual evaluation is presented. Notably, the classic analysis of thermal phenomena in these structures, which was independent of dissipated power magnitude and boundary conditions in the case, is incorrect.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.13 no.6
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• pp.187-193
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• 2013

In multi-agent systems, How to coordinate the behaviors of the agents through learning is a very important problem. The most important problems in the multi-agent system are to accomplish a goal through the efficient coordination of several agents and to prevent collision with other agents. In this paper, we propose a novel approach by using hybrid learning strategy. It is used hybrid learning strategy to control the multi-agent system efficiently by using the spatial relationship among the agents. Through experiments, we can see approximate faster the goal then other strategies and avoids collision among the agents.

• The Journal of the Korea institute of electronic communication sciences
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• v.13 no.2
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• pp.443-448
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• 2018

Recently, Hybrid Electric Vehicle(: HEV) is in the spotlight to global warming caused by carbon dioxide and emission reduction. HEV consists of a combination of mechanical engine and electric motor system. The flow of energy required to drive a HEV depends on the driving conditions of the vehicle. In this paper, we study the contents of HEV education using real-time monitoring system. A real-time monitoring system consisting of hardware and virtual programs is used to simulate the overall operation of a HEV through simulations according to driving conditions and to explain how to learn through hardware.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2013.05a
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• pp.749-750
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• 2013

Due to the rapid development of smart phones, smart phone users grew, expanding communication between the service users has been enabled by the application's service. Difficult to find a service that allows you to know the quality of school meals and the expectations of these applications. In addition, the existing application works only with a particular device, it is difficult to compatible devices. Thus, based on the HTML5 hybrid application were developed and this feed can be monitored by the students of the school, the communication can be formed.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.11 no.4
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• pp.165-169
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• 2011

In recent years mobile phone handset terminal has tended to have additional various functions and slim and light weight, and its internal space is getting smaller and narrower. According to complex parts, small and narrow inner space is caused not sufficient bandwidth and lower impedance. Moreover, additional polarization loss by the surrounding parts produces is lower effectiveness and increases difficulties for getting the antenna gain. For IFA is low profile structure based on the ILA(Inverted L Antenna) which is transformed from the monopole antenna. While this antenna has lots of advantages in internal antenna of mobile phone, it has some disadvantage of reduced bandwidth and gains compared with monopole antenna. In this paper, propose vlade hybrid antenna use for the coupling structure.

• Journal of Communications and Networks
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• v.7 no.1
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• pp.76-86
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• 2005

Today's wireless access networks consist of several tiers that overlap each other. Provisioning of real time undisrupted communication to mobile users, anywhere and anytime through these heterogeneous overlay networks, is a challenging task. We extend the end-to-end approach for the handoff management in hybrid wireless data network by designing a fully mobile-controlled handoff for mobile devices equipped with dual mode interfaces. By handoff, we mean switching the communication between interfaces connected to different subnets. This mobile-controlled handoff scheme reduces the service disruption time during both horizontal and vertical handoffs and does not require any modification in the access networks. We exploit the IP diversity created by the dual interfaces in the overlapping area by simultaneously connecting to different subnets and networks. Power saving is achieved by activating both interfaces only during the handoff period. The performance evaluation of the handoff is carried out by a simple mathematical analysis. The analysis shows that with proper network engineering, exploiting the speed of mobile node and overlapping area between subnets can reduce service disruption and power consumption during handoff significantly. We believe that with more powerful network interfaces our proposal of dual interfaces can be realized.