• Fibers and Polymers
• /
• v.2 no.2
• /
• pp.71-74
• /
• 2001

Surface characterization of materials has been considered critical in the development of biomaterials, as many unfavorable responses from the body occur at the interface between a material and the body component. The contact angle measurement is one means to characterize the surface properties and to correlate them to the biocompatibility of materials. In this paper, surface characteristics of silk fibroin/S-carboxymethyl kerateine, representative fibrous proteins, were investigated by contact angle measurements of ESCA. The biocompatibility of the blends was evaluated based on minimal interfacial free energy concept, and compared with other potential biomaterials. It was also hypothesized that the enhanced surface polarity of the blends was generated from the conformational transition of proteins. This approach to evaluate the biocompatibility of materials based on surface characteristics may find wide utility in many biomedical applications.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
• /
• 2004.11a
• /
• pp.251-253
• /
• 2004

Though the reference angle has been specified conventionally on the slack bus, it can be specified on my bus in the system without changing power flow solutions. This paper describes that the loss sensitivity of the salk bus can be obtained through an angle reference transposition. A concept of two reference buses, consisting of "power slack bus"

• International Journal of Aeronautical and Space Sciences
• /
• v.9 no.2
• /
• pp.58-63
• /
• 2008

This paper describes aerodynamic performance enhancement of cycloidal rotor according to the blade pivot point movement and the blade preset angle adjustment. Cycloidal blade system which consists of several blades rotating about an axis in parallel direction and changing its pitch angle periodically, is a propulsion mechanism of a new concept vertical take off and landing aircraft, cyclocopter. Based on the designed geometry of cyclocopter, numerical analysis was carried out by a general purpose commercial CFD program, STAR-CD. According to tills analysis, the efficiency of cycloidal rotor could be improved more than 15% by the introduced methods.

• Journal of Institute of Control, Robotics and Systems
• /
• v.17 no.2
• /
• pp.125-130
• /
• 2011

This paper shows a method to design complementary filter using least square. The complementary filter is one of useful filters estimating angle. The basic concept of this filter is to enhance advantages of each sensor that angle detecting using a gyroscope has good accuracy at a high frequency and an accelerometer at a low frequency. When designing complementary filter, the most commonly used method is using cut-off frequency. However, it may be not easy to obtain a cut-off frequency. This paper presents a systematic method to determine the coefficients of the complementary filter using well-known linear least squares minimizing error between estimating angle and true angle.

• 한국정보디스플레이학회:학술대회논문집
• /
• 2009.10a
• /
• pp.1440-1443
• /
• 2009

We have devised a methodology based on the concept of foveal (or parafoveal) vision to investigate viewing angle related mura of a backlight unit (BLU). Three different cases of mura phenomenon in BLUs are studied with optical simulation software ASAP in this work. Simulation results, illuminance comparisons between emitting light from BLUs without and with "angle sorting" as well as experimental results are presented. They show good agreement between simulations and experimental observations that demonstrates the method's validation and robustness.

• Tribology and Lubricants
• /
• v.30 no.2
• /
• pp.86-91
• /
• 2014

This paper presents a design procedure for a face gear and pinion used in a handpiece with a $160^{\circ}\acute{y}$ contra angle and 1:2 gear ratio. Based on the geometric theory of gearing, the tooth profile of the face gear and pinion is developed. To analyze the contact pressure, the gear profile should be determined before calculating the stress between the two gears. The concept of calculating the face gear profile is that it can be generated by the coordinate transformation of the shaper profiles, which have involute curves, using a simulation method from the gear manufacturing process.

• Journal of International Academy of Physical Therapy Research
• /
• v.9 no.2
• /
• pp.1513-1516
• /
• 2018

The purpose of this study was to identify the effect of upper thoracic mobilization on cervical alignment in stroke patients with forward head posture. The subject's of this study were two stroke patients with forward head posture and a cervical curve angle (four-line Cobb's method; FLCM) less than $40^{\circ}$. The intervention, central posterior-anterior (PA) mobilization, was applied to the T1-T4 vertebrae (upper thoracic spine) following the Maitland concept. This mobilization was applied three times per week for four weeks. In the results, the cervical curve angle (FLCM) increased for both subject 1 and 2. However, Jochumsen method score was decreased in subject 1, while it was increased in subject 2. These results demonstrate that upper thoracic mobilization had the positive effect on the cervical curve angle but not on Jochumsen method score. These findings suggest that PA mobilization on the upper thoracic spine could correct cervical curve angle measured by FLMC in stroke patients with FHP.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.16 no.5
• /
• pp.61-65
• /
• 2002

RM(Switched Reluctance Motor)＇s Torque is generated by phase-current and inductance profile. A new analytical concept is proposed to determine the turn-off angle for maximization of the torque output. This paper describes a new method to maximization the average torque of a current control Switched Reluctance Motor. It is based on the simplified turn-off angle equation using least square method. Simulations carried out on a three-phase 6/4 pole SRM justify the algorithm is described. The suggested maximization average torque is verified by simulation in this paper.

• The Proceeding of the Korean Institute of Electromagnetic Engineering and Science
• /
• v.3 no.2
• /
• pp.3-9
• /
• 1992

The reponse of the angled two-strip transmission lines illuminated by an external electromagnetic field is estimated by using the circuit concept approach. Calculated terminal voltages reveal convergence to a fixed value as the number of discretization increases. The amplitude patterns of two terminal voltages to all the direction and polarization of the incident field are also calculated.

• 제어로봇시스템학회:학술대회논문집
• /
• 1988.10a
• /
• pp.131-136
• /
• 1988

In this paper we describe a motion control algorithm for a 4-legged robot over slopped terrain and steps. The new concept of the mechanically constrained angle has been introduced and the algorithm has been developed based on the relationship between the gait stability margin and the slope angle. The result then has been extended to the case where the robot walks over steps.