• Title/Summary/Keyword: Control Thresholds

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Design of the control Algorithm for Improvement of the Convenience the Active-type Walking Aid (전동 보행보조기의 편의성 향상을 위한 제어기 설계)

  • Lee, D.K.;Kong, J.S.;Goh, M.S.;Kang, S.J.;Lee, S.M.;Lee, E.H.
    • Journal of rehabilitation welfare engineering & assistive technology
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    • v.5 no.1
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    • pp.17-25
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    • 2011
  • This paper aims to find the optimal control gain for enhancing the convenience of electric walking frames and design a control algorithm. With the recent advances in medical technology, there has been a rapid increase in the aging population and a variety of mobile walking frames have been developed for improvement of the quality of life. However, the manual walking frames of such mobile aids don't have any electric motor which helps facilitate elderly users' walking and thus are not efficient enough for the old people of weak strength to use especially when moving on uneven surfaces such as slopes or thresholds. The types of electric walking frames have been developed to overcome such inefficiency. Electric walking frames require users' control operations for motor driving unlike manual frames. Therefore, when they are not properly handled, it causes considerable inconvenience to their users. The present study compared the electric walking frames with manual ones in terms of operational convenience and attempted to improve the user convenience of walking frames varying the control value for user convenience based on certain standards. This paper presented a haptic sensor designed to recognize the will to walk and measure the degree of convenience and proposed a control algorithm for improvement of convenience. For user convenience, this paper evaluated the relative convenience of walking frames in view of changing differences between the center of vehicle (COV) and the center of position (COP). With the employment of an electric walking frame and a new measuring method, all the processes were experimentally tested and validated.

Adaptive Error Control Scheme for Supporting Multimedia Services on Mobile Computing Environment (이동 컴퓨팅 환경에서 멀티미디어 서비스 지원을 위한 적응적 에러 제어 기법)

  • Jeon Yong-Hun;Kim Sung-Jo
    • The KIPS Transactions:PartC
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    • v.13C no.2 s.105
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    • pp.241-248
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    • 2006
  • Mobile computing has such characteristics as portability, wireless network, mobility, etc. These characteristics cause various problems to mobile terminals like frequent disconnection, high error rate, and varying network status. These problems motivate us to develop an adaptive error control mechanism for supporting multimedia service in mobile computing environment. In this paper, we propose the Adaptive Error Control(AEC) scheme using client's buffer size and current error rate. After categorizing the status into four groups according to client's buffer size and current error rate, this scheme applies an appropriate error control scheme to each status. In this scheme, thresholds of buffer size and error rate are determined by the data transmission time, play rate and average VOP size, and by the probability of error for a sequence of packets. The performance of proposed scheme is evaluated by flaying MPEG-4 files on an experimental client/server environment, respectively. The results show that error correcting rate is similar to other schemes while the time for correcting error reduce a little. In addition, the size of data for correcting error is decreased by 23% compared with FEC and Hybrid FEC, respectively. Theses results demonstrate that the proposed scheme is more suitable in mobile computing environment with small bandwidth and varying environment than existing schemes.

Evaluation of Taste in the Patients with Oral Lichen Planus by Electrogustometer (전기미각측정기를 이용한 구강편평태선환자의 미각평가)

  • Kim, Jung-Woo;Park, June-Sang;Ko, Myung-Yun;Ahn, Yong-Woo
    • Journal of Oral Medicine and Pain
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    • v.31 no.2
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    • pp.113-120
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    • 2006
  • The purpose of this study was to investigate whether there were any changes in taste sensitivity with oral lichen planus (OLP). Sixty subjects (26 males and 34 females) were included for the study and they were categorized into 2 groups (oral lichen planus 30 persons,control 30 persons), oral lichen planus group was investigated in the department of Oral Medicine, College of Dentistry, Pusan National University from April, 2005 to February, 2006 and control group was investigated in the clinic at Cheongju City from february, 2006 to april, 2006. The electrical taste thresholds were measured using an electrogustometer of the 4 different sites (tongue tip, tongue lateral, circumvallate papilla and soft palate) in oral cavity. The results were as follows; 1. The electrical taste threshold showed a tendency to decrease in the OLP group. 2. The electrical taste threshold showed a tendency to decrease in female group, but showed a tendency to increase in male group of the OLP group. 3. The electrical taste threshold showed a tendency to increase in tongue tip, tongue lateral of the multiple OLP group, but showed a tendency to decrease in circumvallate papilla, soft palate of the multiple OLP group. 4. The electrical taste threshold showed a tendency to increase in tongue tip, tongue lateral of the acute OLP group, but showed a tendency to decrease in circumvallate papilla, soft palate of the acute OLP group. 5. After treatment, electrical taste threshold was significant lower in soft palate of the OLP group than control group. 6. After treatment, NAS was significantly lower in soft palate of the OLP group than control group.

The Effect of GCSB-5 a New Herbal Medicine on Changes in Pain Behavior and Neuroglial Activation in a Rat Model of Lumbar Disc Herniation

  • Cho, Hee Kyung;Kim, So-Yeon;Choi, Mi Jung;Baek, Seung Ok;Kwak, Sang Gyu;Ahn, Sang Ho
    • Journal of Korean Neurosurgical Society
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    • v.59 no.2
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    • pp.98-105
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    • 2016
  • Objective : Lumbar disc herniation can induce sciatica by mechanical compression and/or chemical irritation. The aim of this study was to compare the effects of GCSB-5 (Shinbaro$^{(R)}$) and NSAIDs on pain-related behavior and on the expressions of microglia, astrocytes, CGRP, TRPV1, IL-6, and CX3CL1 in a rat model of lumbar disc herniation. Methods : 112 male Sprague-Dawley rats underwent implantation of nucleus pulposus to a dorsal root ganglion (DRG). Rats were divided into five groups as follows; a saline group (the vehicle control group) (n=27), a 10 mg/kg aceclofenac group (the aceclofenac group) (n=22), and 100, 300 or 600 mg/kg GCSB-5 groups (the GCSB-5 100, 300, or 600 groups) (n=21 for each group). Rats were tested for mechanical allodynia at 3 days after surgery and at 1 day, 3 days, 7 days, 14 days, 21 days, 28 days, 35 days, 42 days, 49 days, and 56 days after treatment commencement. Immunohistochemical staining of microglia (Iba1), astrocytes (GFAP), CGRP, and TRPV1, and PCR for IL-6 and CX3CL1 were performed on spinal dorsal horns and DRGs at 56 days after medication commencement. Results : After 56 days of GCSB-5 300 administration, mechanical withdrawal thresholds were significantly increased (p<0.05), and immunohistochemical expressions of Iba1, GFAP, CGRP, and TRPV1 were reduced than other groups, but this difference was not statistically significant. Conclusion : These results indicate GCSB-5 reduces mechanical allodynia and downregulates neuroglial activity and the expressions of CGRP and TRPV1 in the spinal segments of a rat model of lumbar disc herniation.

A Blockade of the Central MAPK Pathway Attenuates Referred Pain in Rats with Complete Freund's Adjuvant -Induced Inflammation of the Temporomandibular Joint

  • Won, Kyoung-A.;Lim, Nak-H.;Lee, Min-K.;Park, Min-K.;Yang, Gwi-Y.;Park, Yoon-Yub;Ahn, Dong-K.;Bae, Yong-C.
    • International Journal of Oral Biology
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    • v.35 no.3
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    • pp.83-89
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    • 2010
  • We investigated the role of the central MAPK pathways in extra-territorial (referred) pain resulting from inflammation of the temporomandibular joint (TMJ). Experiments were carried out on male Sprague-Dawley rats weighing 220-280 g. Under anesthesia, these animals were injected with $50\;{\mu}L$ of complete Freund's adjuvant (CFA) into the TMJ using a Hamilton syringe. In the control group, saline was injected into the TMJ. To identify the extent of inflammation of the TMJ, Evans blue dye (0.1%, 5 mg/kg) was injected intravenously at 1, 3, 6, 9, 12 and 15 days after CFA injection. The concentration of Evans blue dye in the extracted TMJ tissue was found to be significantly higher in the CFA-treated animals than in the saline-treated group. Air-puff thresholds in the vibrissa pad area were evaluated 3 days before and at 3, 6, 9, 12, 15 and 18 days after CFA injection into the TMJ. Referred mechanical allodynia was established at 3 days, remained until 12 days, and recovered to preoperative levels at 18 days after CFA injection. This referred mechanical allodynia was observed in contralateral side area. To investigate the role of central MAPK pathways, MAPK inhibitors ($10\;{\mu}g$) were administrated intracisternally 9 days after CFA injection. SB203580, a p38 MAPK inhibitor, significantly attenuated referred mechanical allodynia, as compared with the vehicle group. PD98059, a MEK inhibitor, also reduced CFA-induced referred mechanical allodynia. These results suggest that TMJ inflammation produces extra-territorial mechanical allodynia, and that this is mediated by central MAPK pathways.

Effect of Microcurrent Stimulation at Hand Somatic Acupuncture Points on Experimental Pain Threshold (미세전류가 수부체성경혈점의 실험적 통증 역치에 미치는 영향)

  • Cho Jung-Sun;Chen Jae-Kyun;Park Rae-Joon
    • The Journal of Korean Physical Therapy
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    • v.6 no.1
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    • pp.85-93
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    • 1994
  • The purposes of this study were 1) to examine the effects of microcurrent electrical neuromuscular stimulation 2) to compare surface electrode with needle electrode at somatic acupuncture points on experimental pain threshold measured at the distal end of the radius 3) to determine the changes in effect over time. A total of sixty healthy adult male and female subjects were assigned randomly to one of two experimental group or to a control group. Group 1(n=20) received MENS(Microcurrent Electrical Neuromuscular Stimulation) with surface electrode. Group 2(n=20) received HENS with needle electrode. Group 3(n=20) received no MENS. It measured experimental pain threshold at the wrist on pretreatment, 0 min after treatment. 15 min after treatment, 30 min after treatment in two experimental group. The results were as follows: 1. Experimental pain thresholds were higher in males than females(P<0.01). 2. Only the experimental group exhibited a significant increased in pain threshold after MENS treatment(P<0.05). 3. Surface electrode group increased significant pain threshold 0 min, 15 min after treatment, but greatly decrease 30 min after treatment. 4. Needle electrode group increased significant pain threshold 0 min, 15 min after treatment, but decrease 30 min after treatment. The results suggest that MENS applied to appropriate somatic acupuncture point can increase pain threshold. Further research is needed to assess the effects of greatly variety intensity of MENS of pain sufferes.

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Circadian Effects on Neural Blockade of Intrathecal Hyperbaric Bupivacaine

  • Lee, Cheol;Choi, Deok-Hwa;Chae, Soo-Uk
    • The Korean Journal of Pain
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    • v.23 no.3
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    • pp.186-189
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    • 2010
  • Background: Neuropathic pain resulting from diverse causes is a chronic condition for which effective treatment is lacking. The goal of this study was to test whether dexamethasone exerts a preemptive analgesic effect with bupivacaine when injected perineurally in the spared nerve injury model. Methods: Fifty rats were randomly divided into five groups. Group 1 (control) was ligated but received no drugs. Group 2 was perineurally infiltrated (tibial and common peroneal nerves) with 0.4% bupivacaine (0.2 ml) and dexamethasone (0.8 mg) 10 minutes before surgery. Group 3 was infiltrated with 0.4% bupivacaine (0.2 ml) and dexamethasone (0.8 mg) after surgery. Group 4 was infiltrated with normal saline (0.2 ml) and dexamethasone (0.8 mg) 10 minutes before surgery. Group 5 was infiltrated with only 0.4% bupivacaine (0.2 ml) before surgery. Rat paw withdrawal thresholds were measured using the von Frey hair test before surgery as a baseline measurement and on postoperative days 3, 6, 9, 12, 15, 18 and 21. Results: In the group injected preoperatively with dexamethasone and bupivacaine, mechanical allodynia did not develop and mechanical threshold forces were significantly different compared with other groups, especially between postoperative days 3 and 9 (P < 0.05). Conclusions: In conclusion, preoperative infiltration of both dexamethasone and bupivacaine showed a significantly better analgesic effect than did infiltration of bupivacaine or dexamethasone alone in the spared nerve injury model, especially early on after surgery.

Effect of Perioperative Perineural Injection of Dexamethasone and Bupivacaine on a Rat Spared Nerve Injury Model

  • Lee, Jeong-Beom;Choi, Seong-Soo;Ahn, Eun-Hye;Hahm, Kyung-Don;Suh, Jeong-Hun;Leem, Jung-Gil;Shin, Jin-Woo
    • The Korean Journal of Pain
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    • v.23 no.3
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    • pp.166-171
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    • 2010
  • Background: Neuropathic pain resulting from diverse causes is a chronic condition for which effective treatment is lacking. The goal of this study was to test whether dexamethasone exerts a preemptive analgesic effect with bupivacaine when injected perineurally in the spared nerve injury model. Methods: Fifty rats were randomly divided into five groups. Group 1 (control) was ligated but received no drugs. Group 2 was perineurally infiltrated (tibial and common peroneal nerves) with 0.4% bupivacaine (0.2 ml) and dexamethasone (0.8 mg) 10 minutes before surgery. Group 3 was infiltrated with 0.4% bupivacaine (0.2 ml) and dexamethasone (0.8 mg) after surgery. Group 4 was infiltrated with normal saline (0.2 ml) and dexamethasone (0.8 mg) 10 minutes before surgery. Group 5 was infiltrated with only 0.4% bupivacaine (0.2 ml) before surgery. Rat paw withdrawal thresholds were measured using the von Frey hair test before surgery as a baseline measurement and on postoperative days 3, 6, 9, 12, 15, 18 and 21. Results: In the group injected preoperatively with dexamethasone and bupivacaine, mechanical allodynia did not develop and mechanical threshold forces were significantly different compared with other groups, especially between postoperative days 3 and 9 (P < 0.05). Conclusions: In conclusion, preoperative infiltration of both dexamethasone and bupivacaine showed a significantly better analgesic effect than did infiltration of bupivacaine or dexamethasone alone in the spared nerve injury model, especially early on after surgery.

The Effect of Urinary Trypsin Inhibitor Against Neuropathic Pain in Rat Models

  • Jung, Ki Tae;Lee, Hyun Young;Yoon, Myung Ha;Lim, Kyung Joon
    • The Korean Journal of Pain
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    • v.26 no.4
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    • pp.356-360
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    • 2013
  • Background: Nerve injury sometimes leads to chronic neuropathic pain associated with neuroinflammation in the nervous system. In the case of chronic neuropathic pain, the inflammatory and algesic mediators become predominant and result in pain hypersensitivity following nervous system damage. It is well known that urinary trypsin inhibitor (ulinastatin, UTI) has an anti-inflammatory activity. Recently, the neuroprotective action of UTI on the nervous system after ischemic injury has been reported. Thus, we evaluated the neuroprotective effect of ulinastatin in a rat model of neuropathic pain. Methods: Neuropathic pain was induced with L5 spinal nerve ligation (SNL) in male Sprague-Dawley rats weighing 100-120 g. The rats were divided into 3 groups, with n = 8 in each group. The rats in the control group (group 1) were administered normal saline and those in group 2 were administered UTI (50,000 U/kg) intravenously through the tail vein for 3 days from the day of SNL. Rats in group 3 were administered UTI (50,000 U/kg) intravenously from the $5^{th}$ day after SNL. The paw withdrawal threshold was measured using the von Frey test for 3 days starting from the $5^{th}$ day after SNL. Results: The paw withdrawal thresholds were significantly increased in the rats of group 2 compared to the other groups (P < 0.05). Conclusions: Ulinastatin, which was administered for 3 days after SNL, increased the paw withdrawal threshold and it could have a neuroprotective effect in the rat model of neuropathic pain.

Analysis of Interference Effect of ESIM on FS System Considering the Antenna Pointing Error (안테나 포인팅 에러를 고려한 ESIM이 FS 시스템에 미치는 간섭 영향 분석)

  • Kang, Young-Houng;Oh, Dae-Sub
    • Journal of Advanced Navigation Technology
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    • v.20 no.6
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    • pp.503-510
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    • 2016
  • In recent years, owing to the growing user demand for the two-way internet service based on the move global broadband communications, a new type of satellite terminal has developed, known as earth station in motion (ESIM). This service was required by Resolution 158 (WRC-15) to study on the coexistence with the co-primary fixed service (FS) in 27.5-29.5 GHz as a FSS uplink. In this paper, four scenarios was introduced to account for the antenna pointing error and the azimuth for an analysis on the sharing between ESIM and FS. From analysis results, the required separation distance between two systems should be about 32~52 km according to the elevation angles of $20^{\circ}{\sim}40^{\circ}$ using thresholds of 5% and 10% outage probability. Therefore, it is necessary to control the azimuth angle due to a moving terminal as well as the pointing error of ESIM to minimize the required separation distance and to protect the co-primary FS.