• The Journal of Korea Institute of Information, Electronics, and Communication Technology
• /
• v.11 no.6
• /
• pp.671-677
• /
• 2018

In this paper, we investigated the vertical alignment characteristics of liquid crystals (LCs) on fluorinated self-assembled monolayers (FSAMs). For comparison, a commercialized homeotropic polyimide (PI) layer was used as an LC alignment layer. We confirmed the successful deposition of FSAMs and the change of FSAMs before and after rubbing treatment through contact angle measurement and atomic force microscopy. The optical transmittance spectrum of the FSAMs is similar to that of the homeotropic PI layer, which is a superior optical characteristic applicable to LC devices. When FSAMs were applied to the vertically aligned (VA) LC cell, uniform and vertical LC alignments were achieved. In addition, the voltage-transmittance characteristic of VA LC cell with FSAMs was superior to that of VA LC cell with the conventional homeotropic PI layers. These results indicate that the FSAMs are suitable as the homeotropic LC alignment layer for enhanced LC devices.

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
• /
• v.28 no.1
• /
• pp.39-51
• /
• 2022

Background: The purpose of this study is to investigate the effect of neck and shoulder self-stretching exercise using audiovisual media on neck pain, postural alignment, and joint position error in women with chronic neck pain. Methods: The subjects included 20 women that gave consent to participate in the study voluntarily. They performed the self-stretching exercises using audiovisual media was carried out 20 minutes 5 times a week during 3 weeks. Neck disability index (NDI) and visual analogue scale (VAS) were used to measure the functional disability and pain, A pressure pain threshold was measured using an algometer, and a cervical range of motion (CROM) measurement tool was used to measure the range of motion and error of proprioceptive position sense of the cervical spine. To assess posture alignment, forward head angle (FHA), forward shoulder angle (FSA) were measured using image J software. Results: The neck pain intensity was statistically significantly within group (p<.05). Neck and shoulder functional disability were a statistically significant difference within group (p<.05). Splenius capitis and upper trapezius pressure pain threshold were statistically significant difference in within group (p<.05). The postural alignment was statistically significantly within group (p<.05). The cervical range of motion in neck extension, right and left lateral flexion were statistically significantly within group (p<.05). The joint position error in neck flexion, extension, right and left lateral flexion decreased statistically significantly within group (p<.05). Conclusion: Self-stretching exercise using audiovisual media increased the mobility of the neck, decreased neck pain and joint position error, and improved posture alignment. As a result, there was a positive effect by applying the self-stretching exercise using audiovisual media to people with neck pain. Based on this, it is thought that it can be used as the basis for research related to home training programs for healthy self-management.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2010.05a
• /
• pp.663-664
• /
• 2010

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
• /
• v.14 no.5
• /
• pp.362-368
• /
• 2021

A homeotropic liquid crystal (LC) alignment state on rubbed fluorinated self-assembled monolayers (FSAMs) is described according to alkyl chain length. A simple procedure, gas-phase method, for the preparation of FSAM was used. The average optical transmittance in the visible light range of FSAMs were 76.63% to 78.21%, which were superior to the conventional polyimide layer having a transmittance of 75.89%. In addition, the excellent homeotropic LC alignment characteristics of FSAMs were observed through pretilt angle measurement and polarized optical microscope images. By measuring the contact angles and the surface energies of FSAMs, it was confirmed that pretilt angles of LC molecules increased according to the alkyl chain length. High optical transparency and uniform homeotropic LC alignment characteristics of FSAMs showed the possibility of FSAMs as an LC alignment layers.

• 한국정보디스플레이학회:학술대회논문집
• /
• 2008.10a
• /
• pp.1105-1106
• /
• 2008

Staggered type self-aligned transparent-oxide-semiconductor transistors with indium-zinc-oxide as a semiconductor have studied. In this device fabrication, successive sputtering of oxide semiconductor and insulator without breaking of vacuum and without exposing in air, humidity and oxygen can be realized because oxide semiconductor is transparent. As a result of fabrication, transistor characteristics with mobility of $30cm^2/Vs$ and on-off ratio of $10^5$ could be obtained for the newly developed self-alignment device structure.

• Journal of the Korean Society of Physical Medicine
• /
• v.15 no.3
• /
• pp.51-59
• /
• 2020

PURPOSE: The purpose of this study was to provide clinical basic data to reduce pain and improve function by comparing neck muscle activity and neck alignment using self-stretching and passive stretching exercises for chronic neck pain caused by forward head posture. METHODS: The subjects were divided into 15 subjects assigned to perform self-stretching exercise and 15 subjects assigned to perform passive stretching exercise. The intervention was conducted for a total of 4 weeks. The muscle activity in the neck was measured by surface electromyography (EMG) before intervention, and craniovertebral and cranial rotation angles were measured by X-ray. The 4-week intervention was conducted and the above items re-measured in the same manner and analyzed. RESULTS: Muscle activity within both groups after intervention using self-stretching or passive stretching exercise was significantly different (p < .05)(p < .01). Neck alignment of both groups was significantly different (p < .001)(p < .01). Further, muscle activities of the upper trapezius and splenius capitis muscles showed significant differences (p<.05). Lastly, neck alignment showed statistically significant difference (p < .05). CONCLUSION: Self-stretching exercise activated motor nerves as a posture correction exercise, thereby improving inhibition of muscle activity, muscle contraction delay, and pathological conditions of the muscle. For future research, interventions of self-stretching exercise will be needed for patients with chronic back pain accompanied by forward head posture, and various clinical studies on postural improvement of forward head posture by maintaining a normal muscle tone state are needed.

• Journal of The Korean Society of Integrative Medicine
• /
• v.1 no.2
• /
• pp.81-92
• /
• 2013

Purpose : This research was carried out to find how neck exercise program combined with self stretching and muscle strengthening program influences on smart phone addicts with forward head posture. Methods : The subjects of this study were 20 smart phone-addicts with forward head posture and we divided them into 2 groups. The experimental group(10 people) participated in neck exercise program as a intervention for 3 months and the control group(the other 10 people) didn't participate in neck exercise program. Neck exercise program were composed of self stretching and muscle strengthening program. Then we measured cervical alignment with GPS(Global Posture System) and evaluated balance ability with Balance Master ver 7.0 systems. Results : The result were as follows. 1. After the intervention, experimental group were significantly more closed to normal cervical alignment than control group. 2. After the intervention, experimental group increased in dynamic balance ability a little more than control group. Conclusion : Neck exercise program seems to get cervical alignment better and improve balance ability.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2009.10a
• /
• pp.687-688
• /
• 2009

• Journal of the Korea Institute of Military Science and Technology
• /
• v.13 no.4
• /
• pp.708-715
• /
• 2010

In Strapdown Inertial Navigation System, alignment accuracy is the most important factor to determine the performance of navigation. However by an existing self-alignment method, it takes a long time to acquire the alignment accuracy that we want. So, to attain the desired alignment accuracy in as little as $\bigcirc$ minutes, we have developed the precise multi-position alignment method. In this paper, it is proposed a inertial measurement matching transfer alignment method among alignment methods to minimize the alignment error in a short time. It is based on a mixed velocity-DCM matching method be suitable to the operating environment of vertical launching system. The compensation methods to reduce misalign error, especially azimuth angle error incurred by measurement time-delay error and body flexure error are analyzed and evaluated with simulation. This simulation results are finally confirmed by experimentations using FMS(Flight Motion Simulator) in Lab and the integration test to follow the fire control mission.

• 제어로봇시스템학회:학술대회논문집
• /
• 2003.10a
• /
• pp.990-994
• /
• 2003

When the low cost IMU is used, the result of the stationary self alignment is not suitable for navigation. In this paper, an in-motion alignment method is proposed to obtain an accurate initial attitude of a low cost IMU based GPS/INS integration system. To design Kalman filter for alignment, large heading error model is introduced. And then Kalman filter is designed to estimate initial attitude error as the indirect feedback filter. In order to assess performance of the alignment method, computer simulations are carried out. The simulation results show that initial attitude error rapidly reduces.