• Proceedings of the IEEK Conference
• /
• 2003.07e
• /
• pp.1799-1802
• /
• 2003

This paper has been studied a Adaptive feature-factors based fingerprints recognition in many biometrics. we study preprocessing and matching method of fingerprints image in various circumstances by using optical fingerprint input device. The Fingerprint Recognition Technology had many development until now. But, There is yet many point which the accuracy improves with operation speed in the side. First of all we study fingerprint classification to reduce existing preprocessing step and then extract a Feature-factors with direction information in fingerprint image. Also in the paper, we consider minimization of noise for effective fingerprint recognition system.

• Journal of the Korean Society for Railway
• /
• v.2 no.4
• /
• pp.32-39
• /
• 1999

A flywheel system which can compensate electric power is presented. The designed system has a capability of providing real and imaginary power instantaneously as well as storing energy. In this paper, a control algorithm is designed. The designed algorithm is to control the secondary side current of the wound rotor induction motor using voltage-based PWM inverter. The flywheel system has advantages in converter size and power quality improvement comparing to the conventional system.

• 대한정형외과스포츠의학회:학술대회논문집
• /
• 2004.09a
• /
• pp.3-3
• /
• 2004

• Journal of the Korean Solar Energy Society
• /
• v.25 no.4
• /
• pp.133-139
• /
• 2005

In this paper, the ventilation performance of suspended particulates in indoor side was investigated by step-down method. Experiments were performed in function of mechanical ventilation types and locations of supply and extract air. The type 2 ventilation system shows the highest removal characteristics rather than other 2 types. It means that the displacement ventilation has also good decay rates of concentration compared to mixing ventilation.

• KIEE International Transactions on Electrophysics and Applications
• /
• v.5C no.6
• /
• pp.257-263
• /
• 2005

WDM optical communication system requires wavelength division multiplexing, reverse multiplexing and optical filter. OADM is a device that can separate or combine specific wavelength of channel from the transmission line. This paper suggests OADM that uses 2 steps FBG based on MZI structure. The OADM that uses 2 steps FBG can minimize the system size and reduce the value of side lobe remarkably. The results obtained in this paper can be used for design and application of OADM that uses 2 steps FBG.

• Journal of the Korean Society of Mechanical Technology
• /
• v.13 no.2
• /
• pp.101-106
• /
• 2011

In this study, the velocity distribution according to upper side coner shape of underwater construction with rectangular cylinder was measured with PIV method and the wake flow characteristics was considered. According to the coner shape, the flow pattern of wake flow was also differed greatly and the step-shaped coner of cut-off ratio B/H=0.06 was similar in the slope shape in result.

• Journal of Soil and Groundwater Environment
• /
• v.6 no.2
• /
• pp.3-13
• /
• 2001

It has been known that nonlinear characteristics of sorption affect the transport behavior of water soluble pollutants in soils. However detailed experimental studies have not been performed to verify the effect of non-linearity of adsorption isotherm on transport of chemicals in porous media. In this research, the distortion of breakthrough curves of a cationic surfactant (cetylpyridinium chloride, CPC) in a engineered stainless steel column packed with glass beads were investigated. Glass beads with about 110 $\mu\textrm{m}$diameter coated with a thin n-decane film were used as the media providing the sorption surface for CPC. The CPC adsorption isotherm on the surface of n-decane from aqueous solution was a typical Langmuir type. The breakthrough curve of CPC using step Input showed a late breakthrough on the front side and early breakthrough on the back side accordance to the shape of the isotherm. The retardation factor of CPC was found to be a strong function of the input concentration, which also a manifestation of the non-linearity of the isotherm. The retardation factors for the CPC with step input agreed with those of pulse input that the maximum concentrations are controlled to be the same as the step input concentrations. This results support the validity of the unproven field practices of using hydrogeotracers with non-linear adsorption isotherms to determine the hydrogeological parameters, e.g., NAPL saturation, air-water or NAPL-water interfacial areas.

• Journal of Korean Physical Therapy Science
• /
• v.27 no.2
• /
• pp.25-35
• /
• 2020

Background: There are many situations where walking in an actual community needs to change direction along with walking on a straight path, and this situation needs to be reflected in assessing walking ability of the community. Therefore, in this study, we tried to determine whether the assessments can distinguish the level of walking in the community. Design: Retrospective cohort study. Methods: Fifty-two survivors with chronic stroke have participated in the study. According to the evaluation result of 10mWT, the subjects of 0.8m/s and above were classified as the group who could walk in the community (n=22), and the subjects of 0.4m/s~0.8m/s were classified into the group who could not walk in the community (n=30). Modified Rivermead Mobility Index, Postural Assessment Scale for Stroke, Fugl-Meyer Assessment, Berg Balance Scale, 10-meter Walk Test (10mWT) were used to evaluate the motor skills. Furthermore, Activities-specific Balance Confidence Scale was used to evaluate psychological factors, and Timed Up & Go Test (TUG), Figure-of-Eight Walk Test (F8WT), Four Square Step Test (FSST), Step Test (ST) were applied to evaluate dynamic balance and mobility. Results: As a result for distinguishing walking levels in the community, TUG was 14.25 seconds, F8WT was 13.34 seconds, FST was 19.43 seconds, and ST of affected side and non-affected side were 6.5 points and 7.5 points, respectively. TUG (AUC=0.923), F8WT (AUC=0.905), and FST (AUC=0.941) were highly accurate, but the ST of affected side and non-affected side (AUC=0.806, 0.705) showed the accuracy of the median degree, respectively. Conclusion: To distinguish walking levels in the community of survivors with chronic stroke, TUG and FSST have been found to be the best assessment tool, and in particular, FSST could be very valuable in clinical use as the most important assessment tool to distinguish walking levels in the community.

• Korean Journal of Applied Biomechanics
• /
• v.32 no.1
• /
• pp.17-23
• /
• 2022

Objective: The aim of this study was to investigate the effect Tiger-step walking on the movement of the lower extremities during walking. Method: Twenty healthy male adults who had no experience of musculoskeletal injuries on lower extremities in the last six months (age: 26.85 ± 3.28 yrs, height: 174.6 ± 3.72 cm, weight: 73.65 ± 7.48 kg) participated in this study. In this study, 7-segments whole-body model (pelvis, both side of thigh, shank and foot) was used and 29 reflective markers and cluster were attached to the body to identify the segments during the gait. A 3-dimensional motion analysis with 8 infrared cameras and 7 channeled EMG was performed to find the effect of tigerstep on uphill walking. To verify the tigerstep effect, a one-way ANOVA with a repeated measure was used and the statistical significance level was set at α=.05. Results: Firstly, Both Tiger-steps showed a significant increase in stance time and stride length compared with normal walking (p<.05), while both Tiger-steps shown significantly reduced cadence compared to normal walking (p<.05). Secondly, both Tiger-steps revealed significantly increased in hip and ankle joint range of motion compared with normal walking at all planes (p<.05). On the other hand, both Tiger-steps showed significantly increased knee joint range of motion compared with normal walking at the frontal and transverse planes (p<.05). Lastly, Gluteus maximus, biceps femoris, medial gastrocnemius, tibialis anterior of both tiger-step revealed significantly increased muscle activation compared with normal walking in gait cycle and stance phase (p<.05). On the other hand, in swing phase, the muscle activity of the vastus medialis, biceps femoris, tibialis anterior of both tiger-step significantly increased compared with those of normal walking (p <.05). Conclusion: As a result of this study, Tiger step revealed increased in 3d range of motion of lower extremity joints as well as the muscle activities associated with range of motion. These findings were evaluated as an increase in stride length, which is essential for efficient walking. Therefore, the finding of this study prove the effectiveness of the tiger step when walking uphill, and it is thought that it will help develop a more efficient tiger step in the future, which has not been scientifically proven.

• Journal of Acupuncture Research
• /
• v.26 no.2
• /
• pp.171-179
• /
• 2009

Objectives: The purpose of this study was to investigate the changes of obesity, blood composition and physical ability in obese children on body weight control program. Methods : The body weight control program included exercise, nutrition education and auricular acupuncture was performed 4 times a week during 12 weeks. 32 obese children whose body fat ratio were over 30% participated in this study. Measuring materials were body composition(weight, muscle mass, fat mass, fat ratio, BMI), physical measurement(height, waist circumference, chest circumference, hip circumference), physical ability(grip strength, sit-ups, sitting trunk flexion, sit-down stand-up test, standing long jump, opened eyes foot balance, side step), blood composition(WBC, Hb, ESR, Total Cholesterol, TG, GOT, GPT, BUN, Creatinine, Glucose) and survey(changes of eating habits, changes of living habits, knowledge of obesity, self-confidence, self-esteem). Results : From the results, positive changes were made in BMI, height, waist circumferences, chest circumferences, hip circumferences, sit-ups, sitting trunk flexion, sit-down stand-up test, standing long jump, opened eyes foot balance, side step, Hb, ESR, GOT, GPT and changes of eating habits through the body weight control program. Conclusions : This results suggest that body weight control program including exercise, nutrition education and auricular acupuncture may be effective for helping obese children.