• 전력전자학회:학술대회논문집
• /
• 전력전자학회 2004년도 전력전자학술대회 논문집(1)
• /
• pp.46-49
• /
• 2004

Switched Reluctance Motor(SRM) has been researched for its superior characteristics. The SRM drive system has simple mechanical and magnetic structure, and it requires simple power electronic drive circuit. It is to be compatible to wide range adjustable speed drive system because it has the same driving characteristics of DC series motor's, easy control principle and high efficiency characteristics. In this paper, 2 types of excitation strategy are researched. Conventional 1-phase excitation and 2-phase excitation method are compared and tested. Though 1-phase excitation method is robust and has high performance, 2-phase excitation method has some merit in appling power device. Some simulation and test results are foaled with some analysis.

• 대한기계학회논문집A
• /
• 제20권11호
• /
• pp.3463-3473
• /
• 1996

The characteristics of wave propagation along a catenary depend on various impedance conditions; i.e., spatial impedance of catenary, impedance of boundaries. In this study, wave propagation along a simple catenary system is studied with arbitrary impedance conditions such as impedance of pantograph, boundary, catenary etc. Seven coupled equations which determine the characteristics of wave propagation along catenary system have been derived and numerically solved. Results demonstrate the role of each impedance condition in the dynamics of catenary system, i.e. the way in which the conditions affect waves on catenary as well as contact force of pantograph. The formulation and suggested solution method can be certainly used for desinging an optimal catenary system for a given pantograph.

• 대한전자공학회논문지
• /
• 제13권3호
• /
• pp.7-10
• /
• 1976

단일 펄스의 Nd-YAG 레이저를 발생시키기 위한 Q-스인치로서 LiNbO3 크리스탈을 사용할때 생기는 난점을 해결하기 위하여 그 중계자 특성을 조사하였으며 간단한 해결 방법을 제시하였다. To eliminate some difficulties encountered in the operation of LiNbO3crystal as a Q-switch for generating a single pulse Nd-YAG laser, the operational characteristics of the crystal, was investigated. Also a simple method for solving the difficulties was presented.

• 대한기계학회:학술대회논문집
• /
• 대한기계학회 2000년도 추계학술대회논문집A
• /
• pp.381-386
• /
• 2000

Simple spring-damper-mass models have been widely used to understand whole-body vertical biodynamic response characteristics of the seated vehicle driver. However, most previous models have not considered about the non-rigid masses(wobbling masses). A simple mechanical model of seated human body developed in this study included the torso represented by a rigid and a wobbling mass. Within the 0.5-20Hz frequency range and for excitation amplitudes maintained below $5ms^{-2}$, this 4-degree-of-freedom driver model is proposed to satisfy the measured vertical vibration response characteristics defined from a synthesis of published data for subjects seated erect without backrest support. The parameters are identified by using the combinatorial optimization technique, simulated annealing method. The model response was found to be provided a closer agreement with the response characteristics than previously published models.

• 대한전기학회논문지:전기물성ㆍ응용부문C
• /
• 제53권11호
• /
• pp.566-571
• /
• 2004

Pulse modulation technique provide additional controling method for electron temperature and density in rf and microwave processing plasma. Transient characteristics of electron density and temperature have been measured in pulse modulated rf inductively coupled argon plasma using simple probe circuit. Electron temperature relaxation is clearly identified in the after glow stage. Controllability of average electron temperature and density depends on the modulation frequency and duty ratio. Numerical calculation of time-dependent electron density and temperature have been performed based on the global model. It has been shown that simple langmuir probe measurement method used for continuous plasma is also applicable to time-dependent measurement of pulse modulated plasma.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
• /
• 제52권7호
• /
• pp.352-360
• /
• 2003

This paper deals with a simple method in order to analyze and compare the harmonic characteristics in the multi-level inverter. Generally, the magnitude of harmonic components becomes different according to the multi-carrier Pulse Width Modulation(PWM) techniques, the modulation index($M_i$) and the switching frequency The previous papers analyzed the harmonic characteristics from the viewpoint of the space voltage vector. Hence, the calculation of the harmonic vector becomes more difficult and complex in 4-level or over 5-level. However, the proposed method has reduced an amount of calculation and simplified the process of it, using the relationship between the reference voltage and the output phase voltage to the load neutral point. It is applied to the 5-level cascade inverter and the harmonic characteristics for each multi-carrier PWM technique are compared through the simulation.

• 대한설비공학회:학술대회논문집
• /
• 대한설비공학회 2008년도 하계학술발표대회 논문집
• /
• pp.901-905
• /
• 2008

This study was conducted to clarify the heat load characteristics and heat and moisture behavior of underground structures. The authors achieved this by carrying out a numerical analysis using simple heat diffusion and simultaneous heat and moisture transfer equations based on measurement data. This paper presents the results of a numerical analysis on the heat load characteristics and heat and moisture behavior of an underground basement and its surrounding ground under a condition of internal heat generation. The authors found it difficult to predict the heat behavior and heat load of the underground basement by simple heat diffusion alone. Accurate prediction of the thermal environment and heat load requires careful consideration of the influences of moisture and precipitation

• ETRI Journal
• /
• 제32권1호
• /
• pp.22-32
• /
• 2010

The pervasive game environments have activated explosive growth of the Internet over recent decades. Thus, understanding Internet traffic characteristics and precise classification have become important issues in network management, resource provisioning, and game application development. Naturally, much attention has been given to analyzing and modeling game traffic. Little research, however, has been undertaken on the classification of game traffic. In this paper, we perform an interpretive traffic analysis of popular game applications at the transport layer and propose a new classification method based on a simple decision tree, called an alternative decision tree (ADT), which utilizes the statistical traffic characteristics of game applications. Experimental results show that ADT precisely classifies game traffic from other application traffic types with limited traffic features and a small number of packets, while maintaining low complexity by utilizing a simple decision tree.

• 전자공학회논문지B
• /
• 제33B권7호
• /
• pp.163-172
• /
• 1996

Recently, it was reported that gaussian distribution and difference of two gaussians (DOG) to have band pass characteristics can be generated by simple iterative processes of the diffusion networks. In this paper, we propose method of improved implementation of a diffusion filter which can reduce total runing time, and operate by simple algorithm in contrast to the latest diffusion filter. We rebuild the diffusion network to a difference network which can generate DOG independently. Different filter characteristics are obtained just by each diffusion process and difference process. Quantitative analysis shows that the center frequency and the selectivity of each filter channel can be varied independently. Also, it would requires smaller amount of hardwares than conventioanl method to build a filter bank.

• 한국생활과학회지
• /
• 제15권2호
• /
• pp.283-292
• /
• 2006

The purpose of this study is to analyze and compare the color characteristics of preferred summer clothing textiles, such as shirts, blouse, slacks and skirt. 109 male and female college students evaluated the preference to clothing textiles in previous research and top 10 kinds of textiles were chosen for each clothing item. To analyze the color characteristics of preferred textiles, spectral data were measured with spectrophotometer. By the results, color and color tone, value of L, a, b according to clothing item and season were compared. Chromaticity diagram was drawn, too. The results of this study are as following: 1. Color characteristics of shirts textile college student preferred for summer was PB color and p tone. The textile, in general, represented simple color that is close to achromatic color with light and soft shade. 2. The most preferred color of blouse textiles was G color and It, d tone. The color characteristics of blouse textiles represented stronger and more brilliant than those of shirts. 3. For slacks, colors of preferred summer textiles were mostly B, YR color and p, It.g, dk tone. Therefore, preferred textiles for slacks represented simple bluish or brownish color that is close to achromatic color with light or dark shade. 4. The most preferred color of skirt textiles were Y, R color and It tone. Skirt textiles had various colors compared to slacks. 5. College students generally prefer simple cold color that is close to achromatic color, because shirts and slacks have high frequency of wearing. In color tone, light and soft tone were preferred for shirts, and for slacks, they preferred light or dark tone. Comparatively, blouse and skirt which have low frequency of wearing represented various colors which contain more brilliant and stronger toned warm colors. 6. By the result of analyzing L, a, b value, shirts and blouse textiles showed higher L value than those of slacks and skirt. The textiles preferred by college students were generally close to achromatic color, because values of a, b were very low. This was confirmed with the result of chromaticity diagram. 7. In pattern of preferred textiles, solid textile were preferred mostly for shirt, blouse, skirt and slacks, and stripe pattern was preferred secondly.