• The Korean Journal of Pain
• /
• 제22권3호
• /
• pp.210-215
• /
• 2009

Background: Several studies have indicated that a nerve injury enhances the expression of the voltage-gated calcium channel ${\alpha}2{\delta}1$ subunit (Cav ${\alpha}2{\delta}1$) in sensory neurons and the dorsal spinal cord. This study examined whether NMDA receptor activation is essential for Cav ${\alpha}2{\delta}1$-mediated tactile allodynia in Cav ${\alpha}2{\delta}1$ overexpressing transgenic mice and L5/6 spinal nerve ligated rats (SNL). These two models show similar Cav ${\alpha}2{\delta}1$ upregulation and behavioral hypersensitivity, without and with the presence of other injury factors, respectively. Methods: The transgenic (TG) mice were generated as described elsewhere (Feng et al., 2000). The left L5/6 spinal nerves in the Harlan Sprague Dawley rats were ligated tightly (SNL) to induce neuropathic pain, as described by Kim et al. (1992). Memantine 2 mg/kg (10 ul) was injected directly into the L5/6 spinal region followed by $10{\mu}l$ saline. Tactile allodynia was tested for any mechanical hypersensitivity. Results: The tactile allodynia in the SNL rats could be reversed by an intrathecal injection of memantine 2 mg/kg at 1.5 hours. The tactile allodynia in the Cav ${\alpha}2{\delta}1$ over-expressing TG mice could be reversed by an intrathecal injection of memantine 2 mg/kg at 1.5, 2.0 and 2.5 hours. Conclusions: The behavioral hypersensitivity was similar in the TG mice and nerve injury pain model, supporting the hypothesis that elevated Cav ${\alpha}2{\delta}1$ mediates similar pathways that underlie the pain states in both models. The selective activation of spinal NMDA receptors plays a key role in mediating the pain states in both the nerve-injury rats and TG mice.

• 한국정보통신학회논문지
• /
• 제11권6호
• /
• pp.1062-1068
• /
• 2007

유비쿼터스게임을 디자인하고 개발하기 위하여 현실세계과 가상세계와의 자연스럽고 다양한 상호작용이 필요하다. 이는 물리적인측면 뿐 아니라 상황변화에 알맞은 대응 감지기술을 필요로한다. 이를 위하여 가상세계와의 유저인터페이스 모델을 정의하고 이를 구현하기 위하여 텍타일감지 시스템을 제작하였다. 텍타일 데이터는 외부환경에 민감하므로 신호처리방법을 사용하여 잡음을 제거하고 유저인터페이스를 위한 데이터 형태로 외부입력을 분석 추론하였다. 이는 일반적인 게임에서 사용하는 마우스나 키보드에 따른 입력과 전혀 다른 형태의 입력으로 유비쿼터스 환경에서의 플레이어의 상황대응에 대한 중요한 정보를 제공하여준다. 구현한 시스템을 통하여 가상공간상에 존재하는 공에 작용한 힘을 3차원적으로 분석하여 힘의 위치, 크기, 분포, 방향 등을 분석하는 방법을 제시 해보았으며 이 같은 실세계 정보 분석을 통하여 가상공간상에서 3차원적인 자연스러운 반작용이 가능하도록 하는 가능성을 보였다. 이 같은 방법들은 유비쿼터스 게임의 상호작용 개발을 위한 기초자료로 사용될 수 있다.

• The Korean Journal of Pain
• /
• 제20권1호
• /
• pp.8-14
• /
• 2007

Background: Anticonvulsants and antidepressants are adjuvant analgesic drugs that are used widely for treating chronic neuropathic pain syndromes. The combined analgesic effect of gabapentin and milnacipran was investigated with a rat neuropathic pain model. Methods: The rat neuropathic pain model was made by ligating the spinal nerves (L5 and L6). An intrathecal catheter was inserted into the subarachnoid space. Tactile allodynia was tested with the up-down method using von Frey hair. We determined the antiallodynic effect of intraperitoneal (I.P.) and intrathecal (I.T.) gabapentin. The combined effect of I.P. gabapentin (50 mg/kg) and milnacipran (0, 10 and 30 mg/kg) was investigated. Results: Intraperitoneal and intrathecal administration of gabapentin increased the threshold for tactile allodynia (the ED50 was 60.6 mg/kg and $45.5{\mu}g$, respectively). Co-administration of I.P. milnacipran increased the antiallodynic effect of I.P. gabapentin in a dose-dependent fashion. Conclusion: The combined administration of milnacipran and gabapentin may increase the total analgesic effect during treatment of neuropathic pain.

• The Korean Journal of Pain
• /
• 제21권1호
• /
• pp.11-17
• /
• 2008

Background: Peripheral nerve injury induces up-regulation of the calcium channel alpha2delta (${\alpha}2{\delta}$) subunit and TRPM8 in the dorsal root ganglion (DRG) which might contribute to allodynia development. We investigated the expression of the ${\alpha}2{\delta}$ subunit and TRPM8 in the DRG of sympathetically maintained pain (SMP) and sympathetic independent pain (SIP) rat model. Methods: For the SMP model, the L5 and L6 spinal nerves were ligated tightly distal to the DRG. For the SIP model, the tibial and sural nerves were transected, while the common peroneal nerve was spared. After a 7 day postoperative period, tactile and cold allodynia were assessed using von Frey filaments and acetone drops, respectively. Expression of the ${\alpha}2{\delta}$ subunit and TRPM8 in the L5 and L6 DRG were subsequently examined by a Western blot. Results: There were no significant differences between the two models for the thresholds of tactile and cold allodynia. Expression of the ${\alpha}2{\delta}$ subunit in the ipsilateral DRG to the injury was increased as determined on a Western blot as compared to that in the contralateral or sham-operated DRG of the SMP model, but there was no difference in expression seen with the use of the SIP model. There was no difference in the expression of TRPM8 in the ipsilateral DRG to the injury and the contralateral or sham-operated DRG of either model. Conclusions: Up-regulation of the ${\alpha}2{\delta}$ subunit in injured DRG may play a role that contributes to tactile allodynia development in SMP, but not TRPM8 to cold allodynia after peripheral nerve injury.

• 융합보안논문지
• /
• 제23권5호
• /
• pp.125-133
• /
• 2023

본 논문은 공유형 전동킥보드 시스템 운영 시, 관리 상 발생할 수 있는 주차 문제를 해결하기 위해 반납 인증사진으로 주차, 비주차 구역을 판단하는 AI모델을 제시한다. 본 연구에서는 주차/비주차 구역 배경 관련 객체를 판별하기 위해 ADE20K에 Pre_trained된 Segfomer_b0 모델과 점자블록, 전동킥보드에 Fine_tuning한 Segfomer_b0 모델을 통해 주차/비주차에 관련된 객체의 Segmentation map을 추출하고, Swin 모델을 통해 주차/비주차 구역을 이진 분류하는 방법을 제시하였다. 최종적으로 총 1,689장을 직접 라벨링한 후 진행한 Fine_tuning SegFomer 모델은 mAP가 81.26% 수준으로 전동킥보드와 점자블록을 인식하였으며, 총 2,817장을 훈련한 Classification 모델은 92.11%의 정확도와 91.50%의 F1-Score로 주차구역과 비주차 구역을 분류하는 것이 가능하였다.

• 한국소음진동공학회:학술대회논문집
• /
• 한국소음진동공학회 2009년도 춘계학술대회 논문집
• /
• pp.280-281
• /
• 2009

Piezoelectric vibrators can be good replacements of electric motors to excite touch screen of a mobile device owing to small volume and low power consumption. One problem to be solved yet for real application is larger excitation force or moment than available currently. More efficient excitation by a piezoelectric vibrator could be achieved by operating at one of resonance frequencies of the system, which must also be as close as possible to frequency range where index finger is most sensitive and increasing transmission force or moment at that frequency. In this study, dynamic models are derived for the piezoelectric exciter and an adhesive viscoelastic layer, which connect the exciter to the screen. The adhesive layer is modeled as distributed stiffness by considering its geometric shape to relative to the piezoelectric exciter. Then, equations of motion for the piezoelectric exciter and the adhesive layer are derived using Hamilton's principle. Based on this model, dynamic characteristics of the exciter will be designed to maximize the force or moment transmitted onto the screen structure.

• 한국섬유공학회:학술대회논문집
• /
• 한국섬유공학회 2003년도 봄 학술발표회 논문집
• /
• pp.259-262
• /
• 2003

Fabric hand is ultimately a subjective response to physical stimuli, but there are clearly practical advantage in the development and commercial trading of textile fabrics to be gained from the replacement of the traditional subjective tactile assessment by an objective measurement evaluation method. Moreover, the reliable objective measurement method for warp knitted fabrics have not developed yet, despite their increasing importance. (omitted)

• 로봇학회논문지
• /
• 제3권1호
• /
• pp.9-15
• /
• 2008

Unlike robotic systems, humans excel at a variety of tasks by utilizing their intrinsic impedance, force sensation, and tactile contact clues. By examining human strategy in arm impedance control, we may be able to teach robotic manipulators human''s superior motor skills in contact tasks. This paper develops a novel method for estimating and predicting the human joint impedance using the electromyogram(EMG) signals and limb position measurements. The EMG signal is the summation of MUAPs (motor unit action potentials). Determination of the relationship between the EMG signals and joint stiffness is difficult, due to irregularities and uncertainties of the EMG signals. In this research, an artificial neural network(ANN) model was developed to model the relation between the EMG and joint stiffness. The proposed method estimates and predicts the multi joint stiffness without complex calculation and specialized apparatus. The feasibility of the developed model was confirmed by experiments and simulations.

• 대한화학회지
• /
• 제62권1호
• /
• pp.43-51
• /
• 2018

이 연구에서는 시각장애를 가진 중고등학생의 물의 상태변화 개념을 조사하였다. 연구대상은 국립과천과학관에서 열린 시각장애학생 대상의 과학탐구 활동에 참여한 중학생 16명과 고등학생 15명으로, 이 중 14명은 전맹, 13명은 저시력이었으며 나머지는 파악되지 않았다. 탐구활동은 이 연구를 위해 제작한 물과 얼음의 분자모형을 참여 학생들에게 개별적으로 탐색하면서 연구자와 대화하는 방식으로 진행하였다. 학생들이 모형에 대한 탐색을 마친 후 물의 상태변화 개념과 관련지어 설명하도록 하였으며, 모형의 활용 가능성에 대해서도 면담을 실시하였다. 모든 대화는 녹음되었고 그 자료를 전사한 뒤 분석하였다. 연구 결과, 시각장애학생들은 활동에 사용된 모형의 재료와 개수에 대해서는 정확히 대답하였지만 무엇을 표현한 모형인지 설명하기 어려워하였다. 물의 분자와 상태변화에 대해 배운 경험이 있다고 대답하였으나 그 개념에 대해 제대로 설명하지 못하거나 현상적인 경험에 기초한 수준에 불과했다. 활동을 통해 시각장애학생들은 물과 얼음의 분자구조와 상태변화에 대해 이해하게 되었고, 연구에서 사용된 모형이 필요하며 유용하다고 긍정적으로 인식하였다. 이러한 결과에 기초하여 교육학적 함의를 논의하였다.

• 한국정밀공학회:학술대회논문집
• /
• 한국정밀공학회 1996년도 추계학술대회 논문집
• /
• pp.841-845
• /
• 1996

Reverse engineering enables a fast creation of CAD model from an existing part without any technical drawing or digital data. This method of data acquisition is necessary in several industrial applications when the modification of an existing product design has to be performed and verified afterwards. In this paper, the surface of an existing ship propeller was measured by a tactile measuring system and the acquired point data of the surface were used for modeling of a solid model in CAD system. By using LOM and casting processes, an aluminum propeller for functional test was manufactured and then its accuracy was measured by a laser scanner and compared with the origin릴 CAD data. As the results show, the use of LOM as a rapid prototyping process and casting as a secondary process delivers a functional prototype propeller which can be used for test purposes.