• Journal of Advanced Marine Engineering and Technology
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• 제36권6호
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• pp.850-856
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• 2012

고정노드 2개를 사용하는 이변측위 방법은 건물이나 선박의 복도와 같은 좁은 공간에서 실시간 실내위치인식 시스템 분야에 사용되고 있다. 하지만 이러한 공간에서 고정노드 간 거리가 멀어지거나 장애물이 있을 경우 위치정보 수신율 저하로 인하여 이동노드(사용자)의 위치 추정이 어렵게 된다. 본 논문에서는 이와 같은 문제를 보완하기 위하여 IEEE 802.15.4a Chirp 신호를 기반으로 사용자에게 부착된 센서를 통하여 위치를 계산할 수 있는 보폭 측정 알고리즘을 이용하는 새로운 실시간 실내위치인식 시스템을 제안한다. 제안한 시스템은 다리길이 측정을 위한 초음파센서, 사용자의 방향을 인식하는 지자기 센서 및 다리사이 각을 획득하기 위한 관성센서로 구성된다. 실험 결과 제안한 시스템은 통신도달성이 결여된 구간에서 기존 실내위치인식 방법에 비해 2배 이상 정교한 결과를 나타내었다.

• Journal of Korean Neurosurgical Society
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• 제46권1호
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• pp.56-59
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• 2009

The lumbar intraspinal epidural ganglion cyst has been a rare cause of the low back pain or leg pain. Ganglion cysts and synovial cysts compose the juxtafacet cysts. Extensive studies have been performed about the synovial cysts, however, very little has been known about the ganglion cyst. Current report is about two ganglion cysts associated with implicative findings in young male patients. We discuss about the underlying pathology of the ganglion cyst based on intraoperative evidences, associated disc herniation at the same location or severe degeneration of the ligament flavum that the cyst originated from in young patients.

• 한국생산제조학회지
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• 제22권6호
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• pp.963-968
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• 2013

In this study, we carried out a structural analysis for determining the stresses acting on the tempered glass of a freely falling cellular phone using ANSYS 13.0, commercial finite element code. We designed a phone heavier than any contemporary cellular phone and performed finite element analysis using the falling speed at a height of 104 cm, which is equal to of the average leg length of Koreans. By determining the maximum stress acting on the phone's tempered glass and frame, we identified the location of large deformation. Furthermore, we evaluated the maximum/minimum equivalent stress and deformation of the reinforced glass and frame as functions of time.

• 제어로봇시스템학회논문지
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• 제18권10호
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• pp.947-954
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• 2012

Sand scorpions are nocturnal animals to mostly use tactile senses to detect their prey. It has been reported that sand scorpions have high vibration sensitivity for their prey-localizing behavior. We tested vibration experiments in the sand with microphone sensors to model the sand scorpion's behavior and a time-difference model was applied to find the direction of a vibration source. Using the information of the arrival time of the vibration signal to reach each leg position, we can find the location of the vibration source.

• 자원환경지질
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• 제29권5호
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• pp.629-637
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• 1996

In this paper a numerical experiment is conducted to determine the low acoustic impedance of a thin oil or gas reservoir from a seismogram by using the generalized linear inversion method. The seismograms used are normal incident synthetic seismograms containing p-wave primary reflections, multiples, and peg-leg multiples on the layers consisting of oil-, gas-, water-filled sandstone incased in shales. In this experiment the acoustic impedance, the location of reservoir boundary, thickness, and source wavelet are assumed initially and revised iteratively by the least-squares-error technique until the difference between the seismogram and calculated one is very small. This experiment shows that the acoustic impedance and thickness, about 10 m thick, can be determined by the inversion.

• Archives of Plastic Surgery
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• 제34권5호
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• pp.562-568
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• 2007

Purpose: Many studies reported anatomy of posterior tibial artery perforator. But, it is not easy to use this flap in clinical case. Methods: Authors performed cadaver dissection on 26 legs from 13 cadavers and identified the number, location, type, length and diameter of perforator. Based on anatomic study, posterior tibial artery perforator flap was performed on 3 clinical cases. Results: The perforator was found on a line drawn from the medial boarder of central patella to posterior boarder of medial malleolus. The main perforator which was longer and greater caliber than others was found was found 13 to 17cm distant from medial boarder of central patella in 23 of 26 leg(88.5%). Average length was 6.2cm and average diameter was 1.4mm. The main perforator was musculocutaneous perforator at 20 of 26 leg(77%). The posterior tibial artery perforator flap was clinically use in 3 cases. All flap were survived without any complication. Conclusion: The author found the main perforator of posterior tibial artery perforator flap was located 15cm distant from medial boarder of central patella within the circle drawn with a radius of 4cm. The posterior tibial artery perforator flap is expected to be used as one of the option for the reconstruction of hand and foot.

• Archives of Plastic Surgery
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• 제39권4호
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• pp.360-366
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• 2012

Background Coverage of defects of the pretibial area remains a challenge for surgeons. The difficulty comes from the limited mobility and availability of the overlying skin and soft tissue. We applied variable pedicled perforator flaps to overcome the disadvantages of local flaps and free flaps on the pretibial area. Methods Eight patients who had the defects in the anterior tibial area were enrolled. Retrospective data were obtained on patient demographics, cause, defect location, defect size, flap dimension, originating artery, pedicle length, pedicle rotation, complication, and postoperative result. The raw surface created following the flap elevation was covered with a split thickness skin graft. Results Posterior tibial artery-based perforator flaps were used in five cases and peroneal artery-based perforator flaps in three cases. The mean age was 54.3 and the mean period of follow-up was 6 months. The average size of the flaps was 63.8 $cm^2$, with a range of 18 to 135 $cm^2$. There were no major complications. No patients had any newly developed functional deficit of the lower leg. Conclusions We suggest that pedicled perforator flaps can be an alternative treatment modality for covering pretibial defects as a simple, safe and versatile procedure.

• 대한화상학회지
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• 제24권2호
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• pp.34-37
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• 2021

A 46-year-old female presented a mass on her right lower leg where she had a burn injury due to moxibustion 10 years ago. Physical examination revealed a 3 cm sized firm nodule with tenderness. Plain radiograph was performed and it revealed well-defined calcifications. According to the history of moxibustion burn injury and the result of plain radiograph, dystrophic calcinosis cutis caused by burn injury was suspected. The patient underwent excisional biopsy using pre-,intra-, and post-operative ultrasonography (USG). There was no sign of recurrence. Herein, we report a case of a 46-year-old healthy woman who presented with single hard nodule on the right lower leg. Our case is worthwhile in two respects. First, It is first case report of dystrophic calcinosis cutis due to moxibustion burn injury. In east asian culture, moxibustion is a commonly conducted procedure and it often induces burn injury. Second, USG was used pre-, intra-, and post-operatively to assess the shape, location, and depth of the calcinosis cutis and to determine the surgical margin.

• Korean Journal of Acupuncture
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• 제24권2호
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• pp.61-76
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• 2007

Objectives : Accurate and reproducible location of an acupuncture point (AP) have been considered an essential component of meaningful acupuncture research as well as clinical practice. Several kinds of devices have been developed and widely used for the convenience of locating APs. However, the accuracy and convenience of these devices have not been systematically evaluated. The present study was performed to find out the most suitable tools for the location accuracy and location easiness of APs among the devices respectively. Methods : Twenty subjects attempted to locate APs, including PC5 and SP6 in the arm and leg, using four different AP positioning methods: one Conventional Ruler method and three alternative methods including Cunometer, Transparent AP meter, and Elastic Ruler method. The position marked on each AP was plotted onto a thin, flexible, and transparent plastic film, and the dispersion rate of the positions was determined and recorded. The elapsed time for locating each AP was measured. After that each subject was answered to a short questionnaire regarding the degree of convenience and confidence of use of each method for AP location. Results : All of three alternative methods took less time than Conventional Ruler method did. Among these alternative methods, the accuracy of Elastic Ruler method was markedly higher than others. The degree of convenience of the Cunometer and the confidence of Elastic Ruler method were the highest among these alternative methods. Conclusions : The present study indicates that the Elastic Ruler method was the most compatible for the conventional Ruler methods. However, there are many factors need to be reconsidered. Improved devices for locating AP are imperatively needed for clinical practice.

• Archives of Plastic Surgery
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• 제33권6호
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• pp.695-699
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• 2006

Purpose: In the 1990s, skin island flap supplied by the vascular axis of the sensitive superficial nerves had been introduced. For example, neurocutaneous flaps supplied by the vascular axis of the sural nerve and saphenous nerve have been used. But the flap supplied by the vascular axis of superficial peroneal nerve has not been used commonly. Because there have been few anatomical reports about the superficial peroneal nerve accessory artery(SPNAA), we could not apply the neurocutaneous flap supplied by SPNAA. The aim of this study is to investigate the anatomy of SPNAA, number and location of its perforators, and septocutaneous perforators from the anterior tibial artery in anterior intermuscular septum. Methods: So, we dissected a total of eight cadavers. Measurements were made of the positions of the dissected arteries and perforators from the head of the fibula. Results: In all cadavers the superior lateral peroneal artery was originated from the anterior tibial artery and contributed SPNAA. Arising from the anterior tibial artery an average of 5.63 cm inferior to the fibular head, it varied from 10 cm to 16 cm in length. SPNAA gave off an average of 4.38 perforators to supply lateral aspect. In one case the inferior lateral peroneal artery was present and arose from the anterior tibial artery 18 cm inferior to the fibular head. There were an average of 3.38 direct septocutaneous perforators from the anterior tibial artery. Conclusion: Septocutaneous perforators from SPNAA mainly exist from proximal 1/6 to 3/5 of lower leg. In the distal 1/3 of lower leg where the accessory artery was disappeared, exist mainly direct septocutaneous perforators from the anterior tibial artery. Our results can be helpful to applications of the neurocutaneous flap using SPNAA or fasciocutaneous flap based on direct septocutaneous perforators.