• 한국정밀공학회:학술대회논문집
• /
• 한국정밀공학회 2011년도 춘계학술대회 논문집
• /
• pp.615-616
• /
• 2011

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 1993년도 정기총회 및 추계학술대회 논문집 학회본부
• /
• pp.272-274
• /
• 1993

In this paper, We were studied the discharge occurrence voltage characteristics. discharge current-discharge voltage characteristics, electron temperature and electron density characteristics on the Facing Tarcket Sputtering System(FTSS) and fabrication of TiN thin films. The discharge occurrence voltage characteristics and discharge current are significantly affected by magnetic flux density. The minimum value of discharge occurrence voltage are obtained about 100[Gauss]. The electron temperature are about 4-8 [eV], and electron density are about $10^{10}cm^{-3}$.

• 한국항해항만학회지
• /
• 제30권2호
• /
• pp.161-166
• /
• 2006

In order to construct an Anechoic Chamber satisfying international standards for EMI testing, it has been recognized that the absorption characteristics of the EM wave absorber must be higher than 20 dB over the frequency band from 30 MHz to 18 GHz. In this paper, an EM wave absorber with super wide-band frequency characteristics was proposed and designed in order to satisfy the above requirements by using the Equivalent Material Constant Method(EMCM) and Finite Difference Time Domain(FDTD). The proposed absorber is to attach a pyramidal absorber onto a hemisphere-type absorber on a cutting cone-shaped ferrite. As a result, the proposed absorber has absorption characteristics higher than 20 dB over the frequency band from 30 MHz to more than 20 GHz.

• KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
• /
• 제2B권3호
• /
• pp.90-94
• /
• 2002

The line start permanent magnet (LSPM) motor has been developed facilitate to the design of the synchronous motor. The rotor of this motor is composed of interior permanent magnets and aluminum bars instead of rotor windings. It is difficult to predict the performance characteristics accurately, because many characteristics are produced by the aluminum rotor bars and the permanent magnets. Therefore, in this paper the dynamic characteristics of the LSPM motor are described and compared via the time-stepped finite element method with those of the cage-type induction motor to find the characteristics of the permanent magnets and the rotor bars in the LSPM motor.

• Structural Engineering and Mechanics
• /
• 제74권1호
• /
• pp.121-128
• /
• 2020

This paper presents an experimental study on the dynamic characteristics of infilled reinforced concrete (RC) frames. A 1/3-scaled, one-bay, three-storey RC frame was produced and tested by using operational modal analysis (OMA). The experiments were performed on five specimens: one reference frame with no infill walls and four frames with infill walls. The RC frame systems included infill walls made of hollow clay brick, which were constructed in four different patterns. The dynamic characteristics of the patterns, including the frequency, mode shapes and damping ratios in the in-plane direction, were obtained by 6 accelerometers. Twenty-minute records under ambient vibration were collected for each model, and the dynamic characteristics were determined using the ambient vibration testing and modal identification software (ARTeMIS). The experimental studies showed that the infill walls significantly affected the frequency value, rigidity and damping ratio of the RC frame system.

• Tribology and Lubricants
• /
• 제25권5호
• /
• pp.285-291
• /
• 2009

In this work, durability characteristics of electrorheological (ER) fluid for damper application are experimentally investigated. ER fluid is prepared by using phosphorated starch particles and silicone oil. The field-dependent Bingham characteristics and response time for the proposed ER fluids are experimentally obtained. Experimental apparatus of durability test for ER fluid is established with cylindrical ER cylinder for mid-sized passenger vehicle. In order to evaluate the durability characteristics of ER fluid as a function of time, damping force and temperature variations are measured until one million cycles. After durability test, Bingham characteristics and response time of ER fluid are measured and compared to the initial properties. Microscopic pictures of ER fluid are taken to validate the changes of properties. The results indicate that the ER fluid can be commercially utilized in vehicle damper system with its durability performance. Moreover, the understanding of durability characteristics is essential to predict the service life of ER fluid as well as to design its applications.

• 한국HCI학회:학술대회논문집
• /
• 한국HCI학회 2007년도 학술대회 1부
• /
• pp.268-273
• /
• 2007

In this paper, we present effective methods for automatic music recommendation system which automatically recommend music by signal processing technology. Conventional music recommendation system use users’ music downloading pattern, but the method does not consider acoustic characteristics of music. Sometimes, similarities between music are used to find similar music for recommendation in some method. However, the feature used for calculating similarities is not highly related to music characteristics at the system. Thus, our proposed method use high-level music characteristics such as rhythm pattern, timbre characteristics, and the lyrics. In addition, our proposed method store features of music, which individuals queried, to recommend music based on individual taste. Experiments show the proposed method find similar music more effectively than a conventional method. The experimental results also show that the proposed method could be used for real-time application since the processing time for calculating similarities between music, and recommending music are fast enough to be applicable for commercial purpose.

• 한국지반공학회:학술대회논문집
• /
• 한국지반공학회 2004년도 춘계학술발표회
• /
• pp.253-260
• /
• 2004

Many scholars and researchers has been studied for many kinds of soil characteristics, but a lot of part are still unsolved. Cyclic load-induced decreasing characteristics of strength and stiffness of soils are also well not known among them. To know that, the characteristics of five kinds of soils; clay, plastic and non-plastic silt, sand, and a weathered soil are compared with dividing two types as plastic or non-plastic soils through direct simple shear(DSS) test. From the results of DSS test, it is known that decreasing characteristics of strength and stiffness are different according to soil types. The strength of plastic and non-plastic soils increases with increment of plasticity index and decrement of volume decrease potential, respectively. And the decreasing stiffness of plastic and non-plastic soils increases with decrement of plasticity index and increment of volume decrease potential, respectively.

• 대한의용생체공학회:의공학회지
• /
• 제35권2호
• /
• pp.26-34
• /
• 2014

Little information is available about the characteristics in revolution gait of hemiplegic elderly, which is frequently represented in daily life. It is also hard to elucidate purely the characteristics due to hemiplegia because of no consideration of aging factors. The aim of study is to identify the alteration characteristics of lower extremity joint angles in both straight and revolution gaits together due to hemiplegia through comparing healthy with hemiplegic elderly. Following Institutional Review Board approval, twelve healthy and hemiplegic elderly were participated and the center of body mass (COM) and lower extremity joint angles were measured during straight and revolution gaits using a computer-aided video motion capture system. The results showed that the gait characteristics were generally altered in both straight and revolution gaits due to hemiplegia (p < 0.05). The gait characteristics were then different between the straight and revolution gaits each other. This study may be valuable by identifying for the first time the alterations of the lower extremity joint angles in both straight and revolution gaits due to pure hemiplegia through comparing healthy elderly with hemiplegic elderly.

• 항공우주시스템공학회지
• /
• 제13권4호
• /
• pp.37-42
• /
• 2019

본 논문에서는 장치의 유연성과 소형화를 위해 EHD 잉크젯 프린팅 기술을 이용하여 은 나노 잉크의 굽힘 특성을 확인하였다. EHD 기술을 위한 최적조건을 도출하였고 은 나노 회로의 굽힘 특성을 파악하였다. EHD 프린팅을 위해서는 재료 특성, 밀도, 유량, 전압, 토출 높이 등 각 파라미터 별 최적점을 찾아내는 것이 필수적이므로 작동 높이와 인가 전압에 따른 각각의 최적점을 도출하였다. 또한, 제작한 굽힘 장치를 통해 각 곡률 반경 별 저항을 측정하여 굽힘 특성을 알아보았고, 곡률이 증가함에 따라, 저항변화율이 급격히 증가하는 것을 확인하였다.