• Title/Summary/Keyword: Electrical stimulus

Search Result 199, Processing Time 0.022 seconds

Relationship between electrical stimulus strength and contraction force from the inside of small intestine (전기 자극 강도에 따른 소장 내부에서의 수축력 관계)

  • Woo, S.H.;Kim, T.W.;Lee, J.H.;Park, H.J.;Moon, Y.K.;Won, C.H.;Lee, S.H.;Park, I.Y.;Cho, Jin-Ho
    • Journal of Sensor Science and Technology
    • /
    • v.17 no.1
    • /
    • pp.1-8
    • /
    • 2008
  • Recently, capsule endoscope was developed to observe small intestine in human body. However, the capsule does not have any locomotive ability, which reduces the benefit of the capsule endoscope. Many researches have done to give locomotion to the capsule, still it consumes too much power to generate the motion by small battery. One of the moving method is electrical stimulus that consumes less power than many methods. The electrical stimulus method causes contraction in the small intestine, and it moves the capsule. Some of papers showed it is possible to guide the capsule by electrical stimulus, however the relationship between electrical stimulus at the mucous and contraction force in the small intestine is not reported, yet. In this paper, the mucous in the small intestine was stimulated, and measured the contraction force in the small intestine is shown. The result shows, the relationship between electrical stimulus parameters (voltage, duration) and contraction force. Also, equation between electrical stimulus parameters and contraction force is roughly induced.

Development of Electrical Stimulator for Restoration of Locomotion in Paraplegic Patients (하반신마비 환자에서 보행기능의 복원을 위한 전기자극법의 개발)

  • 박병림;김민선
    • Journal of Biomedical Engineering Research
    • /
    • v.15 no.4
    • /
    • pp.429-438
    • /
    • 1994
  • An electrical stimulator was designed to induce locomotion for paraplegic patients caused by central nervous system injury. Optimal stimulus parameters, which can minimize muscle fatigue and can achieve effective muscle contraction were determined in slow and fast muscles in Sprague-Dawley rats. Stimulus patterns of our stimulator were designed to simulate eleclromyographic activity monitored during locomotion of normal subjects. Muscle types of the lower extremity were classified according to their mechanical property of contraction, which are slow muscle (msoleus m.) and fast muscle (medial gastrocnemius m., rectus femoris m., vastus lateralis m.). Optimal parameters of electrical stimulation for slow muscles were 20 Hz, 0.2 ms square pulse. For fast muscle, 40 Hz, 0.3 ms square pulse was optimal to produce repeated contraction. Higher'stimulus intensity was required when synergistic muscles were stimulated simultaneously than when they were stimulated individually. Electrical stimulation for each muscle was designed to generate bipedal locomotion, so that individual muscles alternate contraction and relaxation to simulate stance and swing phases. Portable electrical stimulator with 16 channels built in microprocessor was constructed and applied to paraplegic patients due to lumbar cord injury. The electrical slimulator restored partially gait function in paraplegic patients.

  • PDF

An Improved FES System for Control of Paralyzed Upper Extremity

  • Ryoo, Young-Jae;Kim, Young-Min;Park, Chul-Soo;Park, Bong-Kee;Lim, Young-Chul
    • Proceedings of the KOSOMBE Conference
    • /
    • v.1993 no.05
    • /
    • pp.120-122
    • /
    • 1993
  • This paper describes an improved FES system to restore paralyzed extremities in spinal cord injury patients. For composing stimulus pattern which is suitable for each muscle, electrical stimulus pattern creating system is also developed by using IBM-PC. In the improved portable FES system using V40 microprocessor, muscle fatigue can be decreased by selecting the stimulus frequency which is proper to the response characteristics of each muscle. Driving softwares for the portable FES system and the stimulus pattern creating system are programmed with assembler and C language. A multichnnel portable FES system is designed to minimize the sire and weight using a D/A converter and 32 channel multiplexer.

  • PDF

The Behavioral Response of Purple Sea Urchins Heliocodaris crassispina to Food and an Electrical Stimulus (자극원에 따른 보라성게(Heliocodaris crassispina)의 이동패턴 분석)

  • Oh, Taegeon;Lee, Jungkwan;Hwang, Hakgin;Pyeon, Yongbeom;Han, Inwoo;Oh, Wooseok;Park, Guenchang;Lee, Kyounghoon
    • Korean Journal of Fisheries and Aquatic Sciences
    • /
    • v.52 no.5
    • /
    • pp.524-533
    • /
    • 2019
  • Sea urchins are hugely destructive of marine forest ecosystems. This study aimed to determine the behavioral response of purple sea Urchins Heliocodaris crassispina to food and an electrical stimulus and to investigate the attraction radius of these stimuli, with an eye to the development of technology for controlling sea urchin numbers. Ten purple sea urchins, housed in circular acrylic tank, were tested against various attractant stimuli. In addition, an experiment was conducted with 200 purple sea urchins in a large water tank to observe movement patterns and the attractiveness of various stimuli. In the smaller experiment, eight out of 10 sea urchins were attracted to food, and these attractive effects were maintained in all except one of the affected urchins. However, the attractant effects of the electrical stimulus were maintained in only three sea urchins. The results of the larger experiment indicated that differences in the attractant power of food and an electrical stimulus were 54%-78%, and approximately 5-15% of sea urchins were attracted by the electrical stimulus.

The Impact of Functional Electrical Stimulus and Proprioceptive Neuromuscular Facilitation to Scapula Adductor on Upper Limb Functions and Gait of the Patients with Stroke

  • Moon, Sang-Hyun;Hong, Wan-Sung;Kim, Sang-Soo;An, Ho-Jung;Song, Young-Hwa;Kim, Yong-Kwon;Choi, Jung-Hyun;Kim, Bo-Kyoung;Kim, Sung-Ho;Choi, Wan-Suk;Min, Kyoung-Ok
    • Journal of International Academy of Physical Therapy Research
    • /
    • v.1 no.2
    • /
    • pp.143-148
    • /
    • 2010
  • The present study examined the effects of functional electrical stimulus(group 1), proprioceptive neuromuscular facilitation(group 2) and combined training of functional electrical stimulus and proprioceptive neuromuscular facilitation(group 3) with scapula adductor muscles on scapula movement, upper limb function and gait in fifteen subjects stroke patients. The training was thirty minutes a day, five times a week for six weeks, obtained result as follow, upper limb function was significant difference in the group 2(p<.05) but no significant difference in other groups. The change of weight bearing were significant difference in all the groups(p<.05), and increase of gait velocity were significant difference in all the group(p<.05). In conclusion, when applied with functional electrical stimulus, proprioceptive neuromuscular facilitation and combined training to the scapular adductor muscles, it was oberved in the course of the experiment that proprioceptive neuromuscular facilitation was the most effective treatment among the three methods applied to the scapula adductors.

  • PDF

A Study on the Light Stimulus Properties by Azobenzene Organic Thin Films (아조벤젠 유기박막의 광자격 특성에 관한 연구)

  • 조수영;김성진;송진원;이순형;정헌상;이경섭
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 1999.05a
    • /
    • pp.41-44
    • /
    • 1999
  • Displacement current was generated in the pressure stimulus and light stimulus. Solution of azobenzene molecules (8A5H) have to character trans-to-cis. Pressure stimulus generate in the pressure and current. light stimulus generate in the displasement current. The Maxwell displacement current measuring technique has been applied for the investigation of azobenzene organic thin films under alternating photoirradiation with ultraviolet(360nm) and visible (450nm) light. The displacement current was generated due to the trans-to-cis photoisomerization by irradiation with ultraviolet light(λ$_1$=360 nm) Whereas the displacement current was generated in the opposite direction due to the cis-to-trans photoisomerization by irradiation with visible light(λ$_2$=450nm). As result, To show twice reaction certainly phase transition in pressure. A first range generated from 24$\AA$$^2$ to 29$\AA$$^2$and second range generated from 20$\AA$$^2$to 24$\AA$$^2$. Also, cetainfy stimulus apper low pressure and high pressure in photoirradiation. To see different every moment phase transition.

  • PDF

Optimal Conditions of Braille Recognition System Using Electrical Stimulus (전기자극을 이용한 점자인식장치의 최적조건)

  • Lee, Seungjik;Shin, Jaeho;Shin, Jaeho
    • Journal of Biomedical Engineering Research
    • /
    • v.17 no.3
    • /
    • pp.373-378
    • /
    • 1996
  • In this paper, we calculated chronaxy value in order to determine the optimal conditions and stimulus pulse of information transmission. We also developed an electrical equivalent circuit of the hand including the contact part, which consists of two resistors (a contact resistor and finger resistor) and a capacitor. The minimum recoulition voltage was measured by using electrical stimulus. We found that the ranges of the above two resistances and the capacitance are 30-130k$\Omega$, 20-60k$\Omega$ and 10-30nF respectively. We found that the minimum recoulition voltage was the lowest at 100-300Hz and 10% of the duty ratio.

  • PDF

Displacement Current Characteristics of DLPC Lipid Monolayer (DLPC 인지질 단분자막의 변위전류 특성)

  • Chai, Yang-Sung;Sang, Jin-Won;Lee, Kyung-Sup
    • Proceedings of the KIEE Conference
    • /
    • 2006.10a
    • /
    • pp.10-11
    • /
    • 2006
  • The azobenzene dendrimer is one of the dendrimeric macromolecules that include the azo-group exhibiting a photochromic character. Due to the presence of the charge transfer element of the azo-group and its rod-shaped structure, these compounds are expected to have potential interest in electronics and photoelectronics, especially in nonlinear optics. In the present paper, we give pressure stimulation to organic thin films and detect the induced displacement current. Functional photoisometrization organic molecular the photo-stimulus to organic monomolecular L films and LB films of dendrimer and SASH were performed. The SASH organic monolayer in case of pressure stimulus occurred that positive course but in case of the photo-stimulus compared positive and negative. It is assumed that generation forms of displacement current were measured when photo-stimulus for impression.

  • PDF

Electrical Characteristics of Nano-Structural Monolayer (나노구조 단분자막의 전기적 특성)

  • Choi, Yong-Sung;Cho, Jang-Hoon;Song, Jin-Won;Lee, Kyung-Sup
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 2006.11a
    • /
    • pp.166-167
    • /
    • 2006
  • Dendrimers represent a new class of synthetic macromolecules characterized by a regularly branched treelike structure. Multiple branching yields a large number of chain ends that distinguish dendrimers from conventional star-like polymers and microgels. The azobenzene dendrimer is one of the dendrimeric macromolecules that include the azo-group exhibiting a photochromic character. Due to the presence of the charge transfer element of the azo-group and its rod-shaped structure, these compounds are expected to have potential interest in electronics and photoelectronics, especially in nonlinear optics. In the present paper, we give pressure stimulation to organic thin films and detect the induced displacement current. Functional photoisometrization organic molecular the photo-stimulus to organic monomolecular L-films and LB films of dendrimer and 8A5H were performed. The 8A5H organic monolayer in case of pressure stimulus occurred that positive course but in case of the photo-stimulus compared positive and negative. It is assumed that generation forms of displacement current were measured when photo-stimulus for Impression.

  • PDF

Evaluation of Stimulus Strategy for Cochlear Implant Using Neurogram (Neurogram을 이용한 인공와우 자극기법 평가 연구)

  • Yang, Hyejin;Woo, Jihwan
    • Journal of Biomedical Engineering Research
    • /
    • v.34 no.2
    • /
    • pp.47-54
    • /
    • 2013
  • Electrical stimulation is delivered to auditory nerve (AN) through the electrodes in cochlear implant system. Neurogram is a spectrogram that includes information of neural response to electrical stimulation. We hypothesized that the similarity between a neurogram and an input-sound spectrogram could show how well a cochlear implant system works. In this study, we evaluated electrical stimulus configuration of CIS strategy using the computational model. The computational model includes stochastic property and anatomical features of cat auditory nerve fiber. To evaluate similarity between a neurogram and an input-sound spectrogram, we calculated Structural Similarity Index (SSIM). The results show that the dynamic range and the stimulation rate per channel influenced SSIM. Finally, we suggested the optimal configuration within the given stimulus CIS. We expect that the results and the evaluating procedure could be employed to improve the performance of a cochlear implant system.