• Journal of the Korea Institute of Information and Communication Engineering
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• v.11 no.11
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• pp.2143-2149
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• 2007

Visual Cortex Stimulator is among artificial retina prosthesis for blind man, is the method that stimulate the brain cell directly without processing the information from retina to visual cortex. In this paper, we propose image construction and recognition model that is similar to human visual processing by recognizing the feature data with orientation information, that is, the characteristics of visual cortex. Back propagation algorithm based on Delta-bar delta is used to recognize after extracting image feature by Kirsh edge detector. Various numerical patterns are used to analyze the performance of proposed method. In experiment, the proposed recognition model to extract image characteristics with the orientation of information from retinal cells to visual cortex makes a little difference in a recognition rate but shows that it is not sensitive in a variety of learning rates similar to human vision system.

• The Journal of the Korea Contents Association
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• v.9 no.9
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• pp.243-248
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• 2009

Among 74 patients who came to pain clinic to treat their backache, 37 patient were randomly allocated to experimental(finger-pressure therapy)group and another 37 patients were allocated to control(transcutaneous electrical nerve stimulator)group. The extent of backache was compared before and after experiment by ANCOVA test at both groups(p<0.005). The reduction of pain level by visual analogue scale at experimental group was statistically significantly bigger than control group when motion with front flexion(1.92), extension after front flexion(2.22), right flexion(1.23), and left flexion(1.21)(p<0.05).

• JSTS:Journal of Semiconductor Technology and Science
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• v.17 no.1
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• pp.35-41
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• 2017

We propose a novel multi-photodiode array (MPDA) based retinal implant IC with on/off stimulation strategy for a visual prosthesis with improved spatial resolution. An active pixel sensor combined with a comparator enables generation of biphasic current pulses when light intensity meets a threshold condition. The threshold is tuned by changing the discharging time of the active pixel sensor for various light intensity environments. A prototype of the 30-channel retinal implant IC was fabricated with a unit pixel area of $0.021mm^2$, and the stimulus level up to $354{\mu}A$ was measured with the threshold ranging from 400 lx to 13120 lx.

• The Journal of Korean Physical Therapy
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• v.12 no.1
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• pp.119-127
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• 2000

In this case report we demonstrated the improvemen of gait pattern and the facilitation of postwalk locomotion on the child who has severe mental retardation with Incomplete gait pattern. Treatments included to stimulate vestibular using balance board and vestibular stimulator, to train weight hearing and shifting, to facilitate visual perception motor coordination, and to train walk ann postwalk locomotion in environment similar to actual daily life. It was performed 130 sessions for 10 months. With this treatment, she could accomplished dynamic stability so that she didn't fall at walk after $1\~2$ months of treatment, and could have done climbing up and down without hand support after 10 months. In gross motor function measure(GMFM), total motor function was improved to $89.98\%$ from $73.53\%$.

• Journal of the Korean Institute of Telematics and Electronics
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• v.15 no.5
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• pp.19-24
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• 1978

In this paper, the functional propertied of vibrotactile sense of skin were studied by means of psycophysical experiments with respect to frequency and waveform of mechanical vibration, two-point threshold, contactor size of stimulators. Furthermore, leased on the experimental result, a small vibrotactile stimulator made of piezoelectrc ireed vibrator array was proposed for a aid blind to recognition of the Korean letters. A tactile output image is presented by an 8 row$\times$1 column array of samall vibrator reeds with 200 Hz rectangular wave, the array fitting on a fore-finger. Under the control of the NOVA mini-computer, the bimorph reeds array could represent any of one of the 24 characters of the Korean vowel and consonant at the 8 positions from left to right on the array. Without learning effect, the identification test of the Korean characters by the designed experimental system was carried out. The average rate of correct response was 90%.

• Journal of Yeungnam Medical Science
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• v.21 no.2
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• pp.207-214
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• 2004

Purpose: This study was carried out to evaluate the efficacy of intravaginal pelvic floor electrical stimulation (FES) therapy on bladder irritability symptoms in stress urinary incontinent women. Materials and Methods: The evaluation before and after treatment included the Blaivas's female Bladder Questionnaire, the quality of life questionnaires and the overall satisfaction with present voiding state using visual analogue test (VAT). All patient were treated for 20 minutes, twice a week for 6 weeks, using a new intravaginal electrical stimulator with microchip (PIC16C74). Results: After the FES therapy, the overall success rate of the SUI was 50.4.% at 9 months. The bladder irritability symptoms such as frequency, nocturia, urgency, residual urine sensation and lower abdominal discomfort were improved. In particular, the symptoms of frequency, urge incontinence, dysuria were significantly improved after the FES therapy at 9 months. The VAT score of the overall satisfaction with the present voiding state was significantly lower after the FES therapy. 73.7% of patients were satisfied with the FES therapy and complications such as hemorrhage, vaginitis, urinary tract infection and pain were not encountered. Conclusion: These results suggest that FES therapy with microchip improves some bladder irritability in SUI women. Therefore, electrical stimulation therapy should be considered as a first line therapy in SUI women with bladder irritability symptoms.

• The Korean Journal of Pain
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• v.22 no.1
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• pp.74-77
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• 2009

Implantable intrathecal pump is one of the therapeutic options for intractable pain. A 24-year-old male with complex regional pain syndrome was suffering from right lower extremity pain. He had all modalities of treatment including spinal cord stimulator. However, his pain had been worse in the past 6 months. His visual analogue pain scale (VAS) was 8-10 and he could not sit or walk. Only opioid was thought to be effective. Then, intrathecal pump was considered. We estimated the minimal effective dose of spinal morphine before implantation. 0.3 mg of morphine was injected intrathecally as a starting dose. Dosage had been increased up to 0.8 mg in 10 days. His VAS score decreased from 8 to 5. He could sleep without pain and walk with crutch. Therefore, intrathecal pump was inserted. He could tolerate to pain. This case suggests that intrathecal morphine delivery can provide effective treatment for intractable non-malignant pain.

• Asian Journal of Turfgrass Science
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• v.22 no.2
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• pp.217-223
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• 2008

This study was conducted to figure out the effect of silicate as growth stimulator on growth of 'Pencrosss' creeping bentgrass. Creeping bentgrass(Agrostis palustris cv. 'Pencross') at the nursery of Sinwon Country Club was used. Silicate was applied at the concentration of 0, $200{\times}$, $500{\times}$, $1.000{\times}$. Polt size was 1 by 2 meter and there were three replications with completely randomized design(CRD). Creeping bentgrass growth was evaluated with visual turf grass quality, root length and No. of tiller density(ea/$cm^2$). Results of this study are as followings; 1. Average root length with silicate was $1.5{\sim}1.9cm$ longer than control. Especially, Root length of silicate was $7{\sim}8cm$ in summer. 2. Tiller density with silicate was $l8{\sim}22ea/cm^2$, $0.4{\sim}2.l$ less than control. But there was no significant difference. 3. Visual turfgrass quality with silicate was $5.0{\sim}8.3$, $0.3{\sim}1.5$ higher than control. But there was no significant difference. In conclusion, silicate might be grown as root growth stimulator of creeping bentgrass during summer in Korea. However, this study was conducted under one year. Accordingly, in-depth experiment should be done over several years.

• 한국가시화정보학회:학술대회논문집
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• 2002.04a
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• pp.51-78
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• 2002

A number of research groups worldwide are studying electronic implants that can be mounted on retinal optic nerve/visual cortex to restore vision of patients suffering from retinal degeneration. The implants consist of a neural interface made of biocompatible materials, one or more integrated circuits for stimuli generation, a camera, an image processor, and a telemetric channel. The realization of these classes of neural prosthetic devices is largely due to the explosive development of micro- and nano-electronics technologies in the late $20^{th}$ century and biotechnologies more recently. Animal experiments showed promise and some human experiments are in progress to indicate that recognition of images can be obtained and improved over time. We, at NBS-ERC of SNU, have started our own retinal implant project in 2000. We have selected polyimide as the biomaterial for an epi-retinal stimulator. In-vitro and in-vivo biocompatibility studies have been performed on the electrode arrays. We have obtained good affinity to retinal pigment epithelial cells and no harmful effect. The implant also showed very good stability and safety in rabbit eye for 12 weeks. We have also demonstrated that through proper stimulation of inner retina, meaning vision can be obtained.