• The Journal of Korean Physical Therapy
• /
• v.23 no.3
• /
• pp.65-70
• /
• 2011

Purpose: We investigated the changes in the stop-signal reaction time (SSRT) and the no-signal reaction time (NSRT) following motor sequential learning in the stop-signal task (SST). This study also determined which of the reduction0s of spatial processing time was better between blocked- and random-SST. Methods: Thirty right-handed healthy subjects without a history of neurological dysfunction were recruited. In all subjects, both the SSRT and the NSRT were measured for the SST. Tasks were classified into two categories based on the stop-signal patterns, the blocked-SST practice group and random-SST practice group. All subjects gave written informed consent. Results: In the blocked-SST group, both the SSRT and the NSRT was significantly decreased (p<0.05) but not significantly changed in the random-SST group. In the SSRT and the NSRT, the blocked-SST group was faster than the random-SST group (p<0.05). In the post-test SST after practice of each group, the SSRT was significantly decreased in the random-SST group (p<0.05), but the NSRT showed no significant changes in either group. Conclusion: These findings demonstrate that random-SST practice resulted in a decrease in internal processing times needed for a rapid stop to visual signals, indicating motor skill learning is acquired through improved response selection and inhibition.

• The Journal of Korean Physical Therapy
• /
• v.23 no.2
• /
• pp.85-90
• /
• 2011

Purpose: The contribution of the supplementary motor area (SMA) to the control of voluntary movement has been revealed. We investigated the changesin the SMA for motor learning of the reaching movement in stroke patient using functional MRI. Methods: The subject was a right-handed 55 year-old woman with left hemiparesis due to an intracerebral hemorrhage. She performed reaching movement during fMRI scanning before and after reaching training in four weeks. The motor assessment scale and surface EMG were used to evaluate the paretic upper limb function and muscle activation. Results: In the fMRI result, contralateral primary sensorimotor cortex (SM1) was activated before and after training. SMA was only activated after training. In addition, muscle activation of the paretic upper limb was similar to that of the unaffected upper limb after training. Conclusion: These findings suggest SMA is related to the execution of a novel movement pattern resulting in motor learning in stroke patients.

• Annals of Clinical Neurophysiology
• /
• v.8 no.1
• /
• pp.44-47
• /
• 2006

Background: The present study used magnetoencephalography (MEG) to investigate the neural substrates for modified version of Treisman's visual search task. Methods: Two volunteers who gave informed consent participated MEG experiment. One was 27- year old male and another was 24-year-old female. All were right handed. Experiment were performed using a 306-channel biomagnetometer (Neuromag LTD). There were three task conditions in this experiment. The first was searching an open circle among seven closed circles (open condition). The second was searching a closed circle among seven uni-directionally open circles (closed condition). And the third was searching a closed circle among seven eight-directionally open circles (random (closed) condition). In one run, participants performed one task condition so there were three runs in one session of experiment. During one session, 128 trials were performed during every three runs. One participant underwent one session of experiment. The participant pressed button when they found targets. Magnetic source localization images were generated using software programs that allowed for interactive identification of a common set of fiduciary points in the MRI and MEG coordinate frames. Results: In each participant we can found activations of anterior cingulate, primary visual and association cortices, posterior parietal cortex and brain areas in the vicinity of thalamus. Conclusions: we could find activations corresponding to anterior and posterior visual attention systems.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
• /
• 1997.11a
• /
• pp.224-227
• /
• 1997

The International Affective Picture System (IAPS) developed by Lang and colleagues[1] is a world-widely adopted tool in studices relating a variety of physiological indices to subjective emotions induced by the presentation of standardized pictures of which subjective ratings are well established in the three dimensions of pleasure, arousal and dominance. In the present stuey we investigated whether distinctive EEG characteristics for six discrete emotions can be discernible using 12 IAPS pictures that scored highest subjective ratings for one of the 6 categorical emotions, i. e., happiness, sadness, fear, anger, disgust, and surprise (Two slides for each emotion). These pictures as visual stimuli were randomly given to 38 right-handed college students (20-26 years old) with 30 sec of exposure time and 30sec of inter-stimulus interval for each picture while EEG signals were recorded from F3, F4, O1, and O2 referenced to linked ears. The FFT technoque were used to analyze the acquired EEG data. There were significant differences in RP value changes of EEG bands, most prominent in theta, between positive positive and negative emotions, and partial also among negative emotions. This result is in agreement with previous studies[2, 3]. However, it requires further studied to decided whether IAPS could be a useful tool for catigorical approaches to emotion in addition to its traditional uwe, namely dimensional to emotion.

• International Journal of Naval Architecture and Ocean Engineering
• /
• v.9 no.5
• /
• pp.525-536
• /
• 2017

Course keeping is hard to implement under the condition of the propeller stopping or reversing at slow speed for berthing due to the ship's dynamic motion becoming highly nonlinear. To solve this problem, a practical Maneuvering Modeling Group (MMG) ship mathematic model with propeller reversing transverse forces and low speed correction is first discussed to be applied for the right-handed single-screw ship. Secondly, a novel PID-based nonlinear feedback algorithm driven by bipolar sigmoid function is proposed. The PID parameters are determined by a closed-loop gain shaping algorithm directly, while the closed-loop gain shaping theory was employed for effects analysis of this algorithm. Finally, simulation experiments were carried out on an LPG ship. It is shown that the energy consumption and the smoothness performance of the nonlinear feedback control are reduced by 4.2% and 14.6% with satisfactory control effects; the proposed algorithm has the advantages of robustness, energy saving and safety in berthing practice.

• Journal of International Academy of Physical Therapy Research
• /
• v.9 no.1
• /
• pp.1406-1412
• /
• 2018

This study aimed to measure the grip strength of the dominant and non dominant hands of right-handed normal adults in the supination, pronation, and neutral positions of the forearms. The subjects of this study were instructed to make the standard posture suggested by the American Society of Hand Therapists (ASHT) in order to minimize the impact of changes in the posture of the body as follows. The grips strength was statistically different between groups (p<.05). In the follow up test using Scheffe test, the grips in the neutral position and supinator position did not show any difference, while the grip in the pronation was smaller than those of the above two other positions. The grips of the mainly used forearm and non-mainly used forearm of the study target did not show any statistically significant difference in the neutral, supinator and pronation positions of the forearm. This study is expected to provide basic information for studying the impact of the positions of the forearms on grip strength, assessing the prehensility of patients in clinical settings, and setting therapeutic goals.

• Journal of the Institute of Electronics and Information Engineers
• /
• v.50 no.11
• /
• pp.36-40
• /
• 2013

A novel design method of ultra wideband bandpass filter using CRLH transmission line with Dumbell type DGS is presented in this paper. Defected Ground Structure and microstrip interdigital capacitor are used to design the ultra wideband (UWB) filter. CRLH transmission line has composite characteristics of low pass and high pass filter. As control of cutoff frequency of low pass and high pass response on CRLH transmission line, we can get characteristic of UWB filter. We designed and simulated for CRLH transmission lines with one, two, four, and eight cells. A UWB filter using four cells CRLH is designed and fabricated to verify the results. The characteristics of designed filter have center frequency of 5GHz and relative bandwidth of 88%.

• Journal of the Institute of Electronics Engineers of Korea TC
• /
• v.45 no.8
• /
• pp.47-52
• /
• 2008

In order to enhance the rejection performance of the UWB bandpass filter based on the Composite Right- and Left-Handed Transmission-line(CRLH-TL) Metamaterial cell, we propose the lowpass filtering concept that fits into the design objectives : Keeping metamaterial property and miniaturization. So the bandpass filter itself is made far less than a quarter-wavelength and a pair of symmetric comprises lowpass filtering blocks are placed before and after the center CRLH filter which comprises tile interdigitated coupled lines and short-circuited stob. The design result will show the size of 'guided wavelength/8', the fractional bandwidth over 100%, the insertion loss much less than 1 dB, a flat Group-Delay and a good return loss performance, as expected.

• Journal of the Optical Society of Korea
• /
• v.16 no.3
• /
• pp.288-291
• /
• 2012

We designed an ultra-wide band-pass filter applicable to microwave reflectometry for KSTAR (Korea Superconducting Tokamak Advanced Research) and to microwave photonics. The proposed ultra-wide band-pass filter exhibits a metamaterial structure characterized by a wide band, low insertion loss, and high skirt selectivity. The proposed filter is applied to enhance the linearity of reflectometry at the output of a VCO (voltage controlled oscillator). The pass-band of the proposed filter is observed at 18~28 GHz, and the out-of-band rejection is below 20 dB. Further, we constructed an unwrapped negative phase of S(2, 1) to verify the characteristics of the metamaterial. The under- and upper-band at lower limits of the pass-band are left- and right-handed, respectively. The group delay of the filter is less than 0.5 ns.

• Journal of the Korean Home Economics Association
• /
• v.49 no.2
• /
• pp.37-49
• /
• 2011

The present study investigated the semantic and syntactic processes in Korean children's sentence comprehension by measuring event-related brain potentials(ERPs). The subjects were 18 right-handed, healthy native Korean children(1st graders), who were free from any hearing problems. While the children listened to the auditory sentence stimuli, ERPs were recorded with the electrodes mounted in a 'Quik-Cap' on the subject's head. The ERP data were recorded and analyzed using the NeuroScan 4.3 and EEGLABv6.03b programs. For statistical analyses, descriptive statistics, three-way repeated measures ANOVA, and t-tests were performed using a SPSS 15.0 PC program. The results indicated that semantic violations elicited a negativity (N400) ranging from 300 to 500 msec. For syntactic violations, children displayed a positivity (P600) ranging from 900 to 1,100 msec. The discovery of N400 and P600 in semantic and syntactic processes respectively, confirmed the suggestion that Indo-European and Korean languages share a common mechanism for sentence comprehension.