• The Korean Journal of Pain
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• 제23권1호
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• pp.78-81
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• 2010

Spinal cord stimulation (SCS) has become an established clinical option for treatment of refractory chronic pain. Current hardware and implantation techniques for SCS are already highly developed and continuously improving; however, equipment failures over the course of long-term treatment are still encountered in a relatively high proportion of the cases treated with it. Percutaneous SCS leads seem to be particularly prone to dislocation and insulation failures. We describe our experience of lead breakage in the inserted spinal cord stimulator to a complex regional pain syndrome patient who obtained satisfactory pain relief after the revision of SCS.

• JSTS:Journal of Semiconductor Technology and Science
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• 제17권1호
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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.

• 대한물리치료과학회지
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• 제5권4호
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• pp.817-830
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• 1998

The purpose of this study is to investigate the relationship between effects of TENS (Transcutaneous Electrical Nerve Stimulation) and IFC(Interferrential Current Therapy) to the change of body surface temperature. Cases are 22 normal persons and 22 patients with low back pain. Digital Infrared Thermal Imaging system was used for the detection of body surface temperature. 50Hz in frequency and 25-35mA in intensity were applied to TENS and IFC, 15 and 10 minutes on each. The results were follows ; 1. TENS and IFC has on effect of decreasing surface temperature, which would be from cardiovascular factors. (P<0.001) 2. The influence of IFC to the body surface temperature is greater than TENS, and it seems to be vasoconstriction of sympathetic activity. 3. There were no significant differences of body surface temperature between the two groups before and after electrical stimulation.

• 한국산학기술학회논문지
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• 제19권1호
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• pp.615-621
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• 2018

본 연구에서는 에너지절감과 실내쾌적성을 높이기 위하여 색온도, 아로마 및 소리 변동리듬의 자극을 가하여 비교분석하였다. 온도$25[^{\circ}C]$, 상대습도 50[RH%], 기류속도 0.02[m/s] 및 조도 1000[lux]가 유지되는 항온항습실에서 뇌파, 심박동 변이 및 바이브라이미지가 측정되었다. 자극 종류는 자극을 가하기 전, 소리 변동리듬 a=1.106 재즈 음원으로 이루어지는 단일자극 그리고 붉은 조명, 아로마향기 및 소리 변동리듬 a=1.106 재즈 음원으로 이루어지는 다감각자극의 세종류로 측정이 이루어졌다. 변동리듬 a=1.106의 재즈 음원, 붉은 조명 및 아로마향기의 다감각자극에서 생산성과 집중력이 향상되었고, 스트레스지수와 피로도가 감소되었다. 또한 변동리듬 a=1.106의 재즈음원, 붉은 조명 및 아로마향기의 다감각자극에서 심박동이 안정되게 유지되었으며, 바이브라이미지의 긴장도와 스트레스 역시 감소되었다. 변동리듬 a=1.106 음원, RED조명 및 쟈스민 향기의 다감각자극이 쾌적성과 집중력 향상에 효과적이라는 것을 알 수 있었으며, 단일감각에 노출되기 전보다 뉴로에너지가 증가한다는 것을 알 수 있었다. 변동리듬 a=1.106 음원, RED조명 및 쟈스민 향기의 다감각자극이 자극을 가하기전보다 또한 단일감각자극을 가했을 때 보다 뉴로에너지가 증가된다는 것을 알 수 있었다.

• 한국운동역학회지
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• 제32권3호
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• pp.94-102
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• 2022

Objective: The purpose of this study was to investigate the effect of acute transcranial direct current stimulation (tDCS) on the isokinetic muscular endurance of the lower extremity for young adults. Method: Thirteen young adults performed isokinetic fatigue tasks for two experimental conditions including real tDCS and sham stimulation protocols. Before and after the task, the tensiomyography was used for evaluating muscle contraction characteristics of vastus medialis and semitendinosus. Paired t-test was performed to compare the fatigue index, changes in maximum radial displacement (∆Dm), delay time (∆Tc), and velocity of contraction (∆Vc) between tDCS conditions. Results: We found no significant differences in the fatigue index between real and sham conditions. In addition, the analyses identified no significant different values of ∆Dm, ∆Tc, and ∆Vc in the vastus medialis and semitendinosus between real and sham conditions. Conclusion: These findings suggest that the tDCS protocols may have no acute effect on lower limb muscle endurance for young adults. Future studies should consider the long-term effects of repetitive tDCS sessions, various stimulation positions, exercise tasks, and participant characteristics to more clearly understand the effect of tDCS on muscle endurance of lower extremities.

• 대한통합의학회지
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• 제8권2호
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• pp.11-20
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• 2020

Purpose : The purpose of this study was to research the effects of dual-hemisphere transcranial direct current stimulation (dual tDCS) and modified constraint-induced movement therapy (mCIMT) to improve upper extremity motor function after stroke. Methods : The study period was from August 2019 to November 2019, and included 24 patients who met the selection criteria. Participants were divided into 2 groups: dual tDCS and mCIMT, and sham dual tDCS and mCIMT group. Dual tDCS and mCIMT group performed mCIMT immediately after applying dual tDCS for 20 minutes, and sham dual tDCS and mCIMT group performed mCIMT immediately after applying sham tDCS for 20 minutes without turning on the power source. Total interventions were conducted 5 times per week for 4 weeks, and mCIMT was conducted for 30 minutes per session for both experimental and control groups. Fugl-Meyer assessment (FMA) and Motor Activity Log scale (MAL) were analyzed before and after 4 weeks of intervention. Results : Both experimental and control groups showed significant changes in FMA, Amount of Use (AOU), and Quality of Movement (QOM) of MAL. When the differences between groups was compared using ANCOVA, the experimental group showed a greater improvement in FMA and AOU of MAL than the control group. Conclusion : In order to enhance the effect of improving upper limb function of stroke patients, dual tDCS could be applied to provide more effective treatment in the clinical setting. Further studies will be needed in larger groups of stroke patients, including long-term follow-up, and multi-group comparisons through the establishment of anodal tDCS and mCIMT, cathodal tDCS, and mCIMT groups to clarify the effects of dual tDCS. In addition, research is needed to establish a protocol for tDCS, and this evidence-based intervention protocol is expected to be used in the clinical setting as an interventional method for various purposes.

• Journal of Biosystems Engineering
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• 제38권2호
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• pp.113-120
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• 2013

Purpose: Stem cells provide new opportunities in the regenerative medicine for human or animal tissue regeneration. In this study, we report an efficient method for the modulating behaviors of electro-active stem cells by micro-electric current stimulation (mES) without using chemical agents, such as serum or induction chemicals. Methods: Dental pulp stem cells (DPSCs) were cultured on the tissue culture dish in the mES system. To find a suitable mES condition to promote the DPSC functions, the response surface analysis was used. Results: We found that a working micro-current of 38 ${\mu}A$ showed higher DPSC proliferation compared with other working conditions. The mES altered the expressions of intracellular and extracellular proteins compared to those in unstimulated cells. The mES with 38 ${\mu}A$ significantly increased osteogenesis of DPSCs compared with ones without mES. Conclusions: Our findings indicate that mES may induce DPSC proliferation and differentiation, resulting in applying to DPSCs-based human or animal tissue regeneration.

• Physical Therapy Rehabilitation Science
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• 제10권1호
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• pp.76-81
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• 2021

Objective: Smartphone addiction can cause forward head posture, carpal tunnel syndrome and depression, and anxiety. Various interventions have been proposed to resolve Smartphone addiction. However, research regarding the efficacy of these interventions remains lacking. This study was conducted to investigate the effect of tDCS (Transcranial Direct Current Stimulation) on smartphone addiction solution and stress reduction. Design: A randomized controlled trial. Methods: The participants were divided randomly into two group (tDCS vs. Control). tDCS was applied to 41 adults (22.95±2.76 years). The tDCS group was applied 2 mA, for 13 minutes twice over a 26 minute period (n₁ = 21). The control (n₂ = 20) was not applied after padding and was applied twice for 13 minutes over a 26 minute period. This study was conducted four times a week for a total of four weeks. Results: Smartphone addiction for tDCS showed significant improvement in the results in the S-score (p<0.05, 95% CI: 0.702, 4.922), and the result of heart rate (HR) and skin conductivity (SC) to stress. The tDCS group and control group showed no significant decrese in the results in the HR (p>0.05, 95% CI: -3.390, 8.332), but tDCS group showed significant decrese in the results in the SC (p<0.05, 95% CI: 0.060, 1.343) Conclusions: This study suggected that smartphone addiction treatment and decreses of stress. The use of tDCS will reduce the addiction rate of adults and reduce stress, so that possible side effects in society can be solved.

• 대한인간공학회지
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• 제18권3호
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• pp.27-39
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• 1999

The purpose of this study was to approve the capability of human sensibility evaluation based on physiological responses and real-time subjective assessments. Three well-trained healthy human subjects were participated in the experiments. We measured physiological responses such as Heart Rate Variability(HRV), Galvanic Skin Response(GSR) and skin temperature under rest and visual stimulation conditions, respectively. Off-time subjective assessments were recorded before and after visual stimulations. Real-time subjective assessments were recorded during visual stimulations. The results of physiological responses and off-time and real-time subjective assessments were quantified and compared. The results showed that the correlation between physiological responses and real-time subjective assessments was high (83%) for both the positive and negative visual stimulation. The correlation between the physiological responses and off-time subjective assessments was high (83%) for the negative visual stimulation but was low (15%) for the positive visual stimulation. Although the current observation is preliminary and requires more careful experimental study, it appears that the correlation between real-time subjective assessment and physiological responses is higher than that of the off-time subjective assessment and physiological responses.

• 터널과지하공간
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• 제23권6호
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• pp.506-520
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• 2013

지열에너지는 기저부하를 제공하는 신재생에너지이나 현재까지 화산지대에만 대부분의 지열발전이 이루어져 왔다. 인공저류층 지열시스템 (Enhanced Geothermal System, EGS)는 비화산지대의 지열발전을 가능하게 할 개념으로 알려져 있으며 수리자극(hydraulic stimulation)이 핵심기술이다. 본 논문은 EGS지열발전의 개발 현황을 소개하고, 수압파쇄와 수리전단이 주 메커니즘인 수리자극의 핵심원리, 설계변수 및 수리자극에 수반되어 발생하는 미소진동의 원리 및 관측기술을 소개한다. 한국에서의 EGS 지열발전을 위하여 필요한 과제를 소개하여 향후 기술개발의 방향을 제시한다.