Reseach on the System to Activate the Home Net-working Industry through a Standardized Certification System for Residential Properties

Choi, Byung-Kyu The Korean Institute of IIIuminating and Electrica 2006 조명·전기설비학회논문지 Vol.20 No.9

In this study, it has been attempted to build up a smart, stable, and integrated Next-generation Home Network (NHN) system capable of supporting more comfortable and convenient life in the future human housing domains, and to find out which institutional tasks are required to activate the related industries. Additionally, this study aims to review a variety of technologies suggested so far in several fields including information and communications, appliance, and building maintenance. This paper analyzes the advantages and disadvantages, acceptance structure and problems of standard technologies and it suggests the political methods and policies to embody them most effectively and integrally in the future. The said certification system is called 'Standardized Certification System for Korean-style Next-generation Home Network Buildings'(abbreviated to K-NHN) as a new system created for the purpose of developing, more effectively, NHN to be introduced in the future.

Regression Analysis of Vibration Phenomenon on the Load Capacity and Elapsed Year of a Power Transformer

Kim, Young-Dal The Korean Institute of IIIuminating and Electrica 2009 조명·전기설비학회논문지 Vol.23 No.3

The majority of the causes for the failures of power transformers in operation are mechanical defects due to vibration. The vibration phenomenon was measured from the power transformers in operation in the substations. The vibration measurement was performed in a $6{\times}4$ structure on one side of each transformer. The vibrations of the measured points were presented in two and three dimensions and analyzed. The results, according to the elapsed year of the transformer and the load capacity to the transformer, were analyzed. These results could be used as basic data with which to establish vibration standards for power transformers. In addition, the load capacity-vibration phenomenon correlation was examined and regression analysis was performed to derive the estimation function. The vibration phenomenon according to the elapsed yeah was also estimated to derive the function. Then the analysis of the power transformers was used to set vibration standards for them based on the vibration data.

Characteristics of Optical Current Sensors by Sensor Design

Kim, Young-Min,Park, Jung-Hwan,Lee, Kwang-Sik,Kim, Jung-Bae,Park, Won-Zoo The Korean Institute of IIIuminating and Electrica 2007 조명·전기설비학회논문지 Vol.21 No.4

This paper will suggest that the 1 cross orthogonal loop type sensor improves on the orthogonal loop form sensor-head, which is available a calibration of the linear birefringence, when a fiber optic current sensor was composed. An output characteristics of the 1 cross orthogonal loop form, a general closed loop form, the orthogonal loop form are compared by the IEC(International Electrotechnical Commission) 60044-8 standard, and the state of polarization is compared with three forms. As a result, when the closed loop form was changed to the orthogonal loop form, retardation decreased 15.3[%]. When the closed loop form was changed to the 1 cross orthogonal loop type, the retardation decreased 33.8[%]. As a result of the Faraday Effect measurement, the 1 cross orthogonal loop form has the highest output characteristic and the lowest error ratio. It met the 0.5 class of the IEC 60044-8 standard. Thus, in application of the 1cross orthogonal loop form, the possibility to develop high reliability fiber optic current sensors that have a high output and stable error ratio rises is increased.

An online Calibration Algorithm using binary spreading code for the CDMA-based Adaptive Antenna Array

Lee, Chong-Hyun The Korean Institute of IIIuminating and Electrica 2006 조명·전기설비학회논문지 Vol.20 No.9

In this paper, an iterative subspace-based calibration algorithm for a CDMA-based antenna array in the presence of unknown gain and phase error is presented. The algorithm does not depend on the array geometry and does not require a prior knowledge of the Directions Of Arrival (DOA) of the signals. The method requires the code sequence of a reference user only. The proposed algorithm is based on the subspace method and root finding approach, and it provides estimates of the calibration vector, the DOA and the channel impulse response, by using the code sequence of a reference user. The performance of the proposed algorithm was investigated by means of computer simulations and was verified using field data measured through a custom-built W-CDMA test-bed. The data show that experimental results match well with the theoretical calibration algorithm. Also, teh study propose an efficient algorithm using the simulated annealing technique. This algorithm overcomes the requirement of initial guessing in the subspace-based approach.

Current Source ZCS PFM DC-DC Converter for Magnetron Power Supply

Kwon, Soon-Kurl The Korean Institute of IIIuminating and Electrica 2009 조명·전기설비학회논문지 Vol.23 No.7

This paper presents the design of zero current switching ZCS pulse frequency modulation type DC-DC converter for magnetron power supply. A magnetron serving as the microwave source in a microwave oven is driven by a switch mode power supply (SMPS). SMPSs have the advantages of improved efficiency, reduced size and weight, regulation and the ability to operate directly from the converter DC bus. The demands of the load system and the design of the power supply required to produce constant power at 4[kV]. A magnetron power supply requires the ability to limit the load current under short circuit conditions. The current source series resonant converter is a circuit configuration which can achieve this. The main features of the proposed converter are an inherent protection against a short circuit at the output, a high voltage gain and zero current switching over a large range of output power. These characteristics make it a viable choice for the implementation of a high voltage magnetron power supply.

A New Routing Protocol in Wireless Ad-hoc Networks with Multiple Radios and Channels

Ko, Sung-Won,Cho, Jeong-Hwan,Hong, Kwon-Eui The Korean Institute of IIIuminating and Electrica 2010 조명·전기설비학회논문지 Vol.24 No.7

We propose a new routing protocol, MCQosR, that is based on bandwidth estimation, admission control, and a routing metric, MCCR - suitable for wireless ad-hoc networks with multiple radios and channels. To use the full capacity of a wireless link, we assume a node with multiple radios for full duplex operation, and a radio using multiple channels to exclude route-intra interference. This makes it possible to use the capacity of a wireless link. Then, to provide bandwidth and delay guarantee, we have a radio with a fixed channel for layer-3 data reception at each node, used to estimate the available bandwidth and expected delay of a wireless link. Based on the estimate of available bandwidth and delay, we apply the call admission control to a new call requiring bandwidth and delay guarantee. New calls with traffic that will overflow link or network capacity are rejected so the accepted calls can use the required bandwidth and delay. Finally, we propose a routing metric, MCCR, which considers the channel contentions and collisions of a wireless link operating in CSMA/CA. MCCR is useful for finding a route with less traffic and distributing traffic over the network to prevent network congestion as much as possible. The simulation of the MCQosR protocol and the MCCR metric shows traffic is distributed and guaranteed service is provided for accepted calls.

Characteristics of the Design of Landscape Lighting of Dongdaeguro in Daegu

An, Ok-Hee,Lee, In-Hyo The Korean Institute of IIIuminating and Electrica 2010 조명·전기설비학회논문지 Vol.24 No.7

The research measured 14 spots including four streetlights, five public buildings, and five officetels to obtain data needed for the improvement of townscape, grasping the characteristics of the design of landscape lighting of Dongdaeguro in Daegu Metropolitan city. The result of the research shows that landscape lighting by outside lightings of buildings had almost no effect and also it was formed with darker landscape lighting due to high buildings that had no effect of outside lighting. In addition, landscape lighting by streetlights have no unity due to different management facilities of the lightstreets.

Study on the Chirped Waveform of the USPR Pulse using the Impulse Response of a Waveguide

Roh, Young-Su The Korean Institute of IIIuminating and Electrica 2010 조명·전기설비학회논문지 Vol.24 No.3

In ultrashort-pulse reflectometry (USPR), a chirped waveform transformed from the USPR source impulse signal via waveguide makes it possible to employ millimeter-wave mixers for the frequency up-conversion process. Consequently, the frequency bandwidth of the USPR system is sufficiently wide to cover a large portion of the electron density profile of the plasma. Some physical aspects of the chirped waveform, such as maximum amplitude and length, are critical factors to determine the performance of the system. In this paper, the propagation of the USPR impulse signal through a rectangular waveguide is numerically studied to derive the chirped waveform using the impulse response of the waveguide. The results of numerical computation show that the chirped waveform significantly depends on the waveguide cutoff frequency as well as the waveguide length.

Direct Growth of TiO₂-Nanotubes on Ti-Mesh Substrate for Photoanode Application to Dye-sensitized Solar Cell

Park, Min-Woo,Lee, Dong-Hoon,Sung, Youl-Moon The Korean Institute of IIIuminating and Electrica 2010 조명·전기설비학회논문지 Vol.24 No.3

Partial anodic oxidation of Ti-mesh with a wire diameter of ~200[${\mu}m$] produces self-aligned $TiO_2$ nanotube arrays (~50[${\mu}m$] in length) on Ti-mesh substrate. The electrolyte used for anodic oxidation was an ethylene glycol solution with an addition of 1.5 vol. % $H_2O$ and 0.2 wt. % $NH_4F$. A dye-sensitized solar cell utilizing the photoanode structure of $TiO_2$-nanotube/Ti-mesh was fabricated without a transparent conducting oxide (TCO) layer, in which Ti-mesh replaced the role of TCO. The 1.93[%] photoconversion efficiency was low, which can be attributed to both insufficient dye molecules attachment and limited electrolyte flow to dye molecules. The optimized nanotube diameter and length as well as the $TiCl_4$ treatment can improve cell performance.

Power Control and Ground Fault Simulations for a Distribution System with a Fuel Cell Power Plant

Hwang, Jin-Kwon,Choi, Tae-Il The Korean Institute of IIIuminating and Electrica 2010 조명·전기설비학회논문지 Vol.24 No.7

Fuel cell (FC) distributed generation (DG) is gradually becoming more attractive to mainstream electricity users as capacity improves and costs decrease. New technologies including inverters are becoming available to provide a uniform standard interconnection of DGs with an electric power system. Some of the operating conflicts and the effect of DG on power quality are addressed and investigated through simulations on a real distribution network with an FC power plant. The results of these simulations have proved load tracking capability following the real and reactive power change of the load and have shown the flow of overcurrent from an FC power plant during the ground fault of a distribution line.