• The Journal of Korean Institute of Communications and Information Sciences
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• v.31 no.11A
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• pp.1101-1112
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• 2006

With the recent growth in demand for high-data rate multimedia services in the wireless environments, the Mobile Broadband Wireless Access (MBWA) technologies, such as WiBro (Wireless Broadband internet) system, are gradually coming into the spotlight. Unlike the conventional mobile communication networks based on cellular system, the WiBro system basically consists of IP based backbone networks that will be ultimately deployed by Ipv6 (IP version six) based backbone networks according to the All-IP trend for the network evolution. In such wireless mobile environments, it is needed to support the mobility management protocol on network layer as well as physical layer and Medium Access Control (MAC) layer in WiBro system. Accordingly, in this paper, we propose a fast handover scheme for improving the handover performance in IPv6 based WiBro system and show that the proposed scheme achieves loss-free and low handover latency during inter-subnet movement of the mobile stations through the simulation.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.10 no.2
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• pp.257-263
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• 2006

With the ever increasing demand for data communication methods, powerline communication has become in interesting alternative method for data communication in home networking. For the purpose of home safety, several sensors will be installed at door, windows, gas alarm, etc. When considering home networking, the sensor data as well as other types of data should be supported in powerline communication. Usually the sensor data do not have priority over isochronous traffics (voice, video traffic), but in the case of urgent situation at home, the data of sensor being aware of the situation should be transmitted earlier than others. The objective in this paper is to develop a method for supporting an urgent data in home networking using powerline communication. We propose a modified algorithm of HomePlug 1.0 and show the results of computer simulation.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.28 no.9B
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• pp.760-773
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• 2003

The Internet is evolving from best-effort service toward an integrated or differentiated service framework with quality-of-service (QoS) assurances that are required for new multimedia service applications. Given this increasing demand for high bandwidth Internet with QoS assurances in the coming years, an IP/MPLS-based control plane combined. with a wavelength-routed dense-wavelength division multiplexing (DWDM) optical network is seen as a very promising approach for the realization of future re-configurable transport networks. This paper proposes a differentiated lambda establishment process for QoS guarantees based on the differentiated MPLS service (DMS) model. According to the QoS characteristics of wavelength in optical links and the type of used Optical Cross-Connect (OXC) nodes in DWDM next generation optical Internet backbone network, a differentiated wavelength assignment strategy that considers QoS recovery capability is also suggested.

• The Transactions of the Korean Institute of Power Electronics
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• v.13 no.4
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• pp.319-327
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• 2008

The demand of a three phase PWM inverter for the purpose of power control or grid-connecting is increasing. This inverter is connected to a grid through an L-filter or LCL-filter to reduce the harmonics caused by switching. An LCL-filter can reduce the harmonic of a low switching frequency and generate a satisfactory level of grid side current with a relatively low-inductance than an L-filter. But the additional poles caused by the LC part affects a stability problem due to induced resonance of the system. This paper presents a compensation method using a power theory to improve performance, the designed LCL-filter system and to reduce the stability problems caused by resonance. The effectiveness of the proposed algorithm is verified by simulations and experiments.

• The Korean Journal of Pain
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• v.6 no.1
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• pp.49-54
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• 1993

The use of intravenous patient-controlled analgesia is an effective and increasingly used means of providing postoperative pain relief. Recently a non-electric, disposable and portable infusor, the Baxter $Infusor^{(R)}$, has developed. This delivers not only a continuous drug infusion but can also deliver extradoses of medication on demand. The present study examined the benefits of two kinds of analgesics for pain management in 28 patients undergoing gynecological surgery. One group, 14 patients, received i.v. meperidine 0.5 mg/kg as loading dose in the recovery room and PCA with meperidine 3 mg/kg/day for 3 days only(M group). In the other group, 14 patients, also received i.v. meperidine 0.5 mg/kg as loading dose in the recovery room and PCA meperidine 3 mg/kg/day for 3 days and droperidol 5 mg(MD group). The PCA device used was the Baxter $Infusor^{(R)}$. This unit was fitted with patient control module which had a flow rate 0.5 ml/hr and the lockout time was 15 min. Resulting from the study, the MD patients in the first and second days post-operatively, reported less pain compared with the M group. VAPS(Visual Analogue Pain Scales) values were $3.52{\pm}l.61$ vs. $2.22{\pm}0.69$, $2.38{\pm}1.12$ vs. $1.45{\pm}0.48$ and $1.93{\pm}1.65$ vs. $0.98{\pm}0.36$, respectively pertaining to M and MD groups. In conclusion, the MD group with meperidine and droperidol(mixed regimen) provided more effective postoperative analgesia than M group(meperidine only).

• Korean Journal of Community Nutrition
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• v.18 no.1
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• pp.11-24
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• 2013

This study was conducted to provide basic data for development of a dietary education textbook and guidebook by investigating and analyzing eating behavior, nutrition knowledge and educational needs in elementary school students. Most of the subjects were eating three meals a day (71.5%) and breakfast (75.3%). The percentage of students who consumed proper amount of meals (49.2%) was low. The percentage of students consuming salty food and fatty foods was 28.6% and 42.1%, respectively. The consumption of meat, fish, egg, bean and tofu was high, while the consumption of vegetables, fruits and seaweed was low. The percentage of students consuming processed food was high, but the percentage reading nutrition labels (34.9%) and hazard analysis critical control point (HACCP) mark (26.9%) when buying processed foods was very low. Total scores of eating behavior and nutrition knowledge were significantly higher in female students than in male students (p < 0.05-p < 0.001). The desirable frequency of the education was once a week (60.5%). The most preferred educational method was 'experiment and cooking practice' (40.1%). The students wanted dietary information as 'cooking' (39.0%). As a result of this study, many problems were found in the eating behavior of students and nutritional knowledge was observed to be low as well. On the other hand, the demand for dietary education was very high. The findings of this study suggested the need for developing dietary education programs in order to encourage proper eating habits of students.

• Journal of Electrical Engineering and Technology
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• v.7 no.2
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• pp.178-183
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• 2012

The design of the integrated quench protection (QP) system for the high current superconducting magnet (SCM) has been fabricated and tested for the toroidal field (TF) coil system of the Korea Superconducting Tokamak Advanced Research (KSTAR) device. The QP system is capable of protecting the TF SCM, which consists of 16 identical coils serially connected with a stored energy of 495 MJ at the design operation level at 35.2 kA per turn. Given that the power supply for the TF coils can only ramp up and maintain the coil current, the design of the QP system includes two features. The first is a basic fast discharge function to protect the TF SCM by a dump resistor circuit with a 7 s time constant in case of coil quench event. The second is a slow discharge function with a time constant of 360 s for a daily TF discharge or for a stop demand from the tokamak control system. The QP system has been successfully tested up to 40 kA with a short circuit and up to 34 kA with TF SCM in the second campaign of KSTAR. This paper describes the characteristics of the TF QP systems and test results of the plasma experiment of KSTAR in 2009.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2010.05a
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• pp.739-742
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• 2010

The demand of MOST interface module is increasing with car-multimedia network system. MOST devices consist of INIC part which controls MOST network and EHC part which is used by user. The efficient data communication between EHC and INIC demands implementation of a proper device driver. This paper presents a design method for I2C communication driver which is used for transmitting control messages between nodes of MOST network. For effetive I2C communication, we design driver with NetService API. For testing the experiment, we use the MOST audio interface deivce for porting driver sources and will develop various driver on MOST device based OS.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.17 no.12
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• pp.2952-2959
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• 2013

In this paper, a smart meter applying the international communication protocols has been developed. A smart meter requires communication protocols for two-way communication and control technology, registration and deregistration of electronic devices between electric power suppliers to exchange data. Standardization for communication protocols of a smart meter has been proceeding both in the US and Europe. The smart meter developed in this paper applied ANSI C12.22 as a communication protocol which is a north american standard. A smart meter should also provide the electric consuming information and electricity charge information to the customer in real time. Thus, the customer can behave the demand response based on this information. In this paper, the measured electricity from the smart meter is reported to the customer, and IHD(In Home Display) implemented with the windows software presents the reported real time data.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2017.10a
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• pp.477-479
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• 2017

With the recent advances in medical technology and health care, the prevention and treatment of diseases has developed. Accordingly aging has rapidly progressed. In this life span and aging society, demand for diagnostic centered medical care is increasing rapidly. In this paper, we propose a wearable patient check system based on FPGA that can be controlled by sensors. In the existing hospital, a doctor or nurse visited the patient every hour to check the condition. However, in this paper, patients, doctors and nurses can check the patient's condition at the desired time using patient check system. In addition, the tilt sensor is used for the patient who is uncomfortable to easily control. The proposed FPGA-based hardware architecture consists of an algorithm for enlarged image processing, a TFT-LCD Controller, a CIS Controller, and a Memory Controller to output the patient's status image. Implemented and validated using the DE2-115 test board with Cyclone IV EP4CE115F29C7 FPGA device and its operating frequency is 50MHz.