• Journal of the Korean Society of Industry Convergence
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• v.10 no.1
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• pp.27-32
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• 2007

It has been recently reported that the SERS (Surface Enhanced Raman Scattering) effect of the silver mirror substrate made by Tollen's method is much superior to that of other substrates. In this study, the experiments for comparison of surface enhancement of silver sol and silver mirror substrates were done, where we checked the characteristics of silver mirror substrate made by Tollen's method. The surface enhancement of fluorescein was analyzed by silver sol and silver mirror substrates. We observed the SERS spectra of fluorescein. The assignments of the vibrational bands shown in SERS spectra are given based on both literature and the semi-empirical calculations at the PM3 methods. The surface enhancement properties for fluorescein showed that the silver mirror was more superior to sliver sol substrates. Spectra of fluorescein revealed that fluorescein was adsorbed on silver surfaces by a common oxygen atom. According to the 'surface selection rule', the vibrations in the band intensities reflect the adsorption orientation of the molecule on to the surface of SERS substrates. Therefore, we deduced that the adsorption orientation of fluorescein was little tilted perpendicular to the silver surfaces by using of the surface selection rules.

• Journal of the Korean Chemical Society
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• v.47 no.1
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• pp.7-12
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• 2003

It was recently reported that the SERS effect of the silver mirror substrate made by Tollen's method is much superior to that of other substrates. In this study, the experiments for comparison were done, where we checked the characteristics of silver mirror substrate made by different reductants, time interval and thermal treatments. We also surveyed correlations in substrates changes, the influence of SERS enhancement, and adsorbed orientation of phenol red.

• The Journal of Korean Physical Therapy
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• v.33 no.2
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• pp.62-68
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• 2021

Purpose: This study examined whether mirror therapy could improve the balance, gait, and motor function of patients with subacute stroke. Methods: Thirty-three patients with subacute stroke were divided randomly into three groups: experimental group1, experimental group2, and the control group. The patients in experimental group1 performed a mirror therapy program on the unaffected side of the lower extremities, and the patients in experimental group2 performed mirror therapy on the affected side of the lower extremities. Both groups performed the exercise for 30 minutes per session, five times a week for four weeks. The control group did not receive mirror therapy. BBS, POMA, 10MWT, and the BRS were used to evaluate the balance, the quality of gait, gait speed, and the motor function before and after the intervention. Results: The gait speed increased significantly in the experimental groups1 and 2 after the intervention. The control group showed no significant difference in the gait speed after the intervention. The change in gait speed before and after the intervention showed a significant difference among the groups. Experimental group1 showed a significant increase in the gait speed compared to that of the control group. Conclusion: This study suggests that mirror therapy could be an effective intervention to improve the gait speed of patients with subacute stroke. On the other hand, there was no difference in the effectiveness of mirror therapy and therapeutic exercise on the balance, gait, and motor function.

• Journal of Welding and Joining
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• v.21 no.2
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• pp.102-110
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• 2003

A visual sensor consisted of polygonal mirror, laser, and CCD camera was proposed to measure the distance to the weld joint for recognizing the joint shape. To scan the laser beam of the sensor onto an object, 8-facet polygonal mirror was used as the rotating mirror. By locating the laser and the camera at axi-symmetrical positions around the mirror, the synchronized-scan condition could be satisfied even when the mirror was set to rotate through one direction continuously, which could remove the inertia effect of the conventional oscillating-mirror methods. The mathematical modelling of the proposed sensor with the optical triangulation method made it possible to derive the relation between the position of an image on the camera and the one of a laser light on the object. Through the geometrical simulation of the proposed sensor with the principal of reflection and virtual image, the optical path of a laser light could be predicted. The position and direction of the CCD camera were determined based on the Scheimpflug's condition to fit the focus of any image reflected from an object within the field of view. The results of modelling and simulation revealed that the proposed visual sensor could be used to recognize the weld joint and its vicinity located within the range of the field of view and the resolution. (Received February 19, 2003)

• Journal of Biomedical Engineering Research
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• v.23 no.4
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• pp.287-293
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• 2002

For non-contact nerve stimulations using time varying magnetic field, high amplitude current pulses have to be applied to a magnetic nerve stimulation coil. To increase the magnetic stimulation frequency we have to increase both power supply capacity and cooling capacity of the magnetic nerve stimulator. To alleviate these problems. we propose a new magnetic nerve stimulation coil design methods. Utilizing magnetic mirror effect of a ferro-magnetic plate attached to a magnetic stimulation coil. we have improved efficiency of the stimulation coil. We have analyzed magnetic mirror effect for various kinds of stimulation coils using the finite element method, and we present experimental results obtained with several kinds of stimulation coils.

• Journal of Sensor Science and Technology
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• v.26 no.1
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• pp.50-55
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• 2017

The measurement of absolute humidity of gases is essential in many industries. The effect of temperature on aluminum oxide and chilled mirror dew-point hygrometers is investigated. The temperature of laboratory, pipe line, and sensor is varied and the dew point is measured by two different aluminum oxide hygrometers. In all cases, the dew point of hygrometers is increased as the temperature is elevated. The reason behind this observation is due to desorption of water from the inside of pipe line and/or sensor surroundings at elevated temperature that result in the increase of the absolute humidity. Moreover, the sensor itself shows a certain degree of temperature dependency in sensing the humidity especially at low temperature. It is also studied that chilled mirror dew-point hygrometer may indicate a higher dew point than the reference at high temperature because the cooling capability of mirror is decreased at high temperature. Our study will provide evidences in the incorporation of the temperature effect as uncertainty factors in the standard calibration procedure for dew point hygrometers.

• Therapeutic Science for Rehabilitation
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• v.2 no.1
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• pp.24-35
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• 2013

The Purpose of this study was to determine the clinical effectiveness of mirror therapy for stroke. Moreover, this paper was designed to summarize clarified information of neurological plasticity by mirror therapy to finally define the neurological mechanism. Mirror therapy improves the stroke patients' hand and arm motor function. It also has a positive influence on recovering performance of activities of daily living and relieving pain. However, it is not evident that mirror therapy restores visual neglect. There are various ways of recovering stroke. Fundamentally, all the theories are on a bases of restoration of premotor area. Premotor area which is associated with motor control increases the activation of primary motor area and finally improves patients' motor function. If primary motor area is completely damaged, premotor area and supplementary motor substitute for primary motor area. In summary of literature survey, there are not enough evidence to verify the effectiveness and neurological mechanism of mirror therapy. In future, more researches should be conducted to verify the neurological recovery through mirror therapy. Then, mirror therapy will be acknowledged as a clinically effective treatment.

• Proceedings of the International Microelectronics And Packaging Society Conference
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• 2001.11a
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• pp.222-225
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• 2001

Optical disk drives read information by replacing a laser beam on the disk track. As information has become larger, the more accurate position control of a laser beam is necessary. In this paper, we report the analysis and fabrication of the micro mirror for optical disk drivers. The mirror was fabricated by using MEMS technology and it's characteristics investigated. Also, electrode structure for reducing squeeze effect was discussed.

• Journal of the Korean Society for Nondestructive Testing
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• v.33 no.2
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• pp.154-159
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• 2013

In this paper, the effect of bolt clamping force and form accuray of contact surface between mirror and mount on mirror surface was studied. Normally, mirror used in reflecting optical system was assembled with mount by bolts or adhesive. In this case, the tension caused by bolt clamping force or adhesive force may distort the mirror surface. Also, form accuracy error of the contact surface have a negative impact on wrenched mirror surface which assembled by bolts or adhesive. In this study, stress and distorted displacements on mirror surface were analyzed according to the different contact surface form accuracies and bolt clamping forces by using the finite element analysis method.

• PNF and Movement
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• v.9 no.4
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• pp.33-40
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• 2011

Purpose : The aims of this study was to identify changes mu rhythm according to familiarity with a stimulus in people with stroke. Methods : Seventeen right-handed participants were asked to observe 2 different stimulus; a non-familiarity stimulus condition (NFSC), and a familiarity stimulus condition (FSC). Electroencephalogram (EEG) signals from electrodes on the participant's scalp were recorded during action observation. The activation of the mirror neuron system was compaired between FSC and NFSC by a paired t-test. An independent t-test was used to compare the difference between right and left hemispheres for the activation of the mirror neuron system during action observation of performing a task with the right hand. Results : The result of paired t-test showed no significantly difference between NFSC and FSC in the activation of the mirror neuron system. The Result of independent t-test also showed no significantly difference in the activation of mirror neuron system between the right and left hemispheres. Conclusion : The familiarity with a stimulus had no signigicant effect on the activation of the mirror neuron system according to the familiarity and in either the right or left hemispheres in people with chronic stroke.