• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제29권6호
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• pp.450-454
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• 2003

Mandibular arteriovenous malformations(AVM) are relatively rare and potentially life threatening lesions. Surgical treatment consists of wide resection of the mandible, which is difficult and potentially hazardous due to significant blood loss during surgery. Therefore, some authors advocate that transvenous embolization may be a safer and more effective method in the treatment of mandibular AVM. We report a treatment case of mandibular AVM in a 9-year-old-girl for episodes of spontaneous bleeding for 6 days using by selective transarterial embolization, direct puncture embolization and microcoil embolization.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제33권1호
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• pp.69-75
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• 2007

The treatment of intraosseous ateriovenous malformation in the jaw is difficult because of life threatening frequent bleeding tendency. The surgical resection of AVM may be mortal due to massive blood loss. In the growing pediatric patient, surgery may cause facial deformity and growth disturbance. So currently, the treatment of AVM is only embolization using various material through endovascular access, direct-puncture or embolization in conjunction with surgical resection. We report a case of combined techniques.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2013년도 추계학술대회
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• pp.492-495
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• 2013

최근 자동차의 수요의 증가로 인해 사용자의 편의 및 안전에 대한 요구와 의존도가 증가함에 따라 운전자를 위한 보조 시스템이 구축되고 있다. 현재 운전자를 위한 보조 시스템으로 AVM(Around View Monitoring) 기술이 개발 되었다. 본 논문에서는 운전자가 차량외부의 상황을 실시간으로 인식할 수 있게 하는 AVM(Around View Monitoring) 기술을 조금 더 실용적이고 편의성 있게 사용할 수 있도록 하는 사용자 인터페이스를 제안한다. 이를 위해 영상이 보이는 화면에 다양한 버튼들을 구현하였으며, 화면상에 보이는 버튼에 따라서 4채널 영상과 4채널 영상을 하나로 정합되어 보여주는 영상 그리고 원본영상과 왜곡영상을 따로 보여주는 다양한 인터페이스를 버튼 식으로 구현하여 운전자가 원하는 영상을 상황에 맞게 제공한다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 A
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• pp.400-402
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• 1999

We have developed a new type Automatic Vending Machine(AVM) of a small size with simplification of coin mechanisms. The AVM adopts a new type transportation system named thin film-transportation system. Thin films have advantages of safe guide and transportation of various goods which made from various materials and shapes. The AVM has advantages of low price and simple mechanisms. The compact size($300{\times}330{\times}630$, mm)is realized by the use of simple coin mechanisms and thin-transportation system.

• Journal of Korean Neurosurgical Society
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• 제30권12호
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• pp.1406-1416
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• 2001

Objective : The goal of this study was to evaluate the effect of Gamma Knife radiosurgery(GKS) on cerebral arteriovenous malformation(AVM) and the factors associated with complete occlusion. Patients and Methods : A total of 369 radiosurgical procedures for 336 patients with cerebral AVMs were performed between December 1988 and June 2001. Three hundreds and twenty-four cases of 293 patients who were treated with GKS procedures from May 1992 to December 2000 were analyzed. Various clinical and radiologic parameters were evaluated. Results : The total obliteration rate for the cases with satisfactory radiological follow-up(more than 2 years) after GKS was 79.3%. In multivariate analysis, maximal diameter, angiographic form of AVM nidus, and number of draining veins significantly influenced the result of radiosurgery. In addition, marginal radiation dose, Spetzler-Martin grade, and flow pattern of AVM nidi also partly influenced the radiosurgical outcome. Conclusion : GKS on cerebral AVM is considered as an effective treatment modality. The risk of hemorrhage seems to decrease within the latency interval between GKS and complete occlusion of nidus. Along with the size, topography, or radiosurgical parameters of AVMs, it is necessary to consider the angioarchitectural and hemodynamic aspects to select proper candidates for radiosurgery.

• Korean Journal of Radiology
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• 제20권8호
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• pp.1285-1292
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• 2019

Objective: To evaluate the safety and efficacy of the coil-protected technique for liquid embolization in neurovascular malformations. Materials and Methods: Twenty-two patients who underwent coil-protected liquid embolization for symptomatic cranial (n = 13) and spinal (n = 9) arteriovenous fistula (AVF) or arteriovenous malformations (AVMs) were identified. A total of 36 target feeder vessels were embolized with N-butyl cyanoacrylate and/or Onyx (Medtronic). This technique was used to promote delivery of a sufficient amount of liquid embolic agent into the target shunt or nidus in cases where tortuous feeding arteries preclude a microcatheter wedging techniqu and/or to prevent reflux of the liquid embolic agent in cases with a short safety margin. The procedure was considered technically successful if the target lesion was sufficiently filled with liquid embolic agent without unintentional reflux. Angiographic and clinical outcomes were retrospectively evaluated. Results: Technical success was achieved for all 36 target feeders. Post-embolization angiographies revealed complete occlusion in 16 patients and near-complete and partial occlusion in three patients each. There were no treatment-related complications. Of the six patients who showed near-complete or partial occlusion, five received additional treatments: two received stereotactic radiosurgery for cerebral AVM, two underwent surgical removal of cerebral AVM, and one underwent additional embolization by direct puncture for a mandibular AVM. Finally, all patients showed complete (n = 19) or near-complete (n = 3) occlusion of the target AVF or AVM on follow-up angiographies. The presenting neurological symptoms improved completely in 15 patients (68.2%) and partially in seven patients (31.8%). Conclusion: The coil-protected technique is a safe and effective method for liquid embolization, especially in patients with various neurovascular shunts or malformations who could not be successfully treated with conventional techniques.

• Journal of Korean Neurosurgical Society
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• 제29권8호
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• pp.995-1000
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• 2000

Objective : The authors reviewed 280 cases with intracranial arteriovenous malformations(AVMs) to identify risk factors of hemorrhage. Patients and Methods : From 1983 to 1997, a total 280 patients with AVMs were treated. Among them, 64% had a history of hemorrhage. Angiograms were retrospectively analyzed with particular attention to the size of the AVM, venous drainage, the location of the AVM and presence of associated aneurysm or varix. These characteristics were statistically analysed in relation to occurrence of hemorrhage. Results : A single variate analysis demonstrated that small size(p=0.0003), deep venous drainage(p=0.025) and periventricular location(p<0.0001) had a strong positive correlation. Associated aneurysms and varices were not found as hemorrhagic risk factors. A multivariate analysis revealed that the size of the AVM was most significant hemorrhagic factor(p=0.0003) followed by deep venous drainage(p=0.025). AVMs with small size and deep venous drainage bled more frequently regardless of their locations. Conclusion : These data would be useful in identifying patients at higher risk for developing hemorrhage of intracranial AVMs.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제41권6호
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• pp.346-351
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• 2015

Angiography is the gold standard for the diagnosis and complete resection of arteriovenous malformations (AVMs). The absence of residual AVM after surgery is commonly believed to reduce the risk of future hemorrhage. However, AVMs can recur after proven complete angiographic resection can occur, albeit rarely, especially in the pediatric population. We report a rare case of a recurrent AVM two years after complete resection in an adult patient. This case report shows that AVMs in adults can recur despite their rarity and despite postoperative angiography confirming complete removal. Moreover, in this case, the recurrent AVM involved a new feeding vessel that was not involved with the initial lesion.

• 로봇학회논문지
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• 제14권3호
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• pp.170-178
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• 2019

This paper proposes a parking space detection method for autonomous parking by using the Around View Monitor (AVM) image and Light Detection and Ranging (LIDAR) sensor fusion. This method consists of removing obstacles except for the parking line, detecting the parking line, and template matching method to detect the parking space location information in the parking lot. In order to remove the obstacles, we correct and converge LIDAR information considering the distortion phenomenon in AVM image. Based on the assumption that the obstacles are removed, the line filter that reflects the thickness of the parking line and the improved radon transformation are applied to detect the parking line clearly. The parking space location information is detected by applying template matching with the modified parking space template and the detected parking lines are used to return location information of parking space. Finally, we propose a novel parking space detection system that returns relative distance and relative angle from the current vehicle to the parking space.

• Journal of Power Electronics
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• 제19권1호
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• pp.288-295
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• 2019

Rectifiers are widely used in industrial applications. Although detailed models of rectifiers are usually used to evaluate their performance, they are complex and time-consuming. Therefore, the Average Value Model (AVM) has been introduced to meet the demand for a simple and accurate model. This type of rectifier modeling can be used to simplify the simulations of large systems. The AVM of diode rectifiers has been an area of interest for many electrical engineers. However, healthy diode rectifiers are only considered for average value modeling. By contrast, faults occur frequently on diodes, which eventually cause the diodes to open-circuit. Therefore, it is essential to model bridge rectifiers under this faulty condition. Indeed, conventional AVMs are not appropriate or accurate for faulty rectifiers. In addition, they are significantly different in modeling. In this paper, a novel application of the parametric average value of a three-phase line-commutated rectifier is proposed in which one diode of the rectifier is considered open-circuited. In order to evaluate the proposed AVM, it is compared with experimental and simulation results for the application of a brushless synchronous generator field. The results clearly demonstrate the accuracy of the proposed model.