• 한국생산제조학회지
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• 제19권6호
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• pp.812-828
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• 2010

A fuel injection system using an ECU HILS as an alternate to a vehicle test for the fuel injectors was developed. The throttle position, vehicle speed, engine speed, crank position, cam position, intake air flow, and several other sensor signals that are supplied to the ECU were measured and recorded as a data file for a vehicle driven in the FTP-75 mode in a chassis dynamometer. Electric signals that are equivalent to the sensor signals from the vehicle are reconstructed from the recorded data file using data acquisition boards, microprocessors, and computers. All sensor signals are supplied to the ECU with synchronized timing using a computer program. The findings show that the cost and time of vehicle experiments can be reduced using the ECU HILS system. Moreover, the repeatability of the generation of sensor signals can enhance the accuracy of a range of experiment related to vehicle testing. An ECU scanner that scans the sensor signals that are input to the ECU through a serial port was used to assess the accuracy of the reconstructed signals. The scanning results show good agreement with the reconstructed input signals. Injectors were connected to the ECU HILS system and were driven by the system to measure the quantity of injected fuel.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제29권5호
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• pp.422-428
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• 2007

The columella, nasal tip, lip relationship in the secondary bilateral cleft deformity remains an enigma and a great challenge for the cleft surgeon. A subset of patients with bilateral cleft lip still require columellar lengthening and nasal correction, despite the advances in preoperative orthopedics and primary nasal corrections. An approach to correct this deformity is described. This consists of 1) lengthening the columella, 2) open rhinoplasty, allowing definitive repositioning of lower lateral cartilages, ear cartilage grafting to the tip and columella when necessary, 3) nasal mucosal advancement, 4) alar base narrowing and 5) reconstruction of the orbicularis oris as required. In surgical repair of the cleft lip nose, the timing of the operation(during lip closure, before or after the puberty growth sput), and the operative technique play a key role in the final result. In this study, 13 cleft lip patients who had undergone a secondary cheilorhinoplasty at the Department of Oral and Maxillofacial Surgery, Pusan National University Hospital were evaluated to check the proper time and method of the operation.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제29권1호
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• pp.60-63
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• 2003

Gunshot injuries can range from the most minor to the life-threatening. Multidisciplinary care is required for successful management of patients, In the acute phase, care may involve emergency surgeons, anaesthesists, neurosurgeons, ophthalmic surgeons, vascular surgeons, ENT specialist in addition to the oral and maxillofacial surgeons. Afterwards, definitive treatment of facial gunshot injuries depends ultimately on the abilities and skills of the oral and maxillofacial surgeons, and their appreciation of such injuries. The timing and sequence of the surgical procedures used for reconstruction and rehabilitation of maxillofacial gunshot injuries are crucial to a successful outcome and aesthetic result. If incorrect, they may lead indefinitely to infection, graft rejection, wound dehiscence with consequent multiple revisional operations and complication which will prolong hospital stay and increase treatment costs and morbidity on those patients. We present a gunshot case of a 46-year-old man who tried to commit sucide, and have avulsive and penerating wounds on the face and the neck. We removed the scattered bullets and fragments successfully and the wounds were closed primarily.

• 대한치과교정학회지
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• 제49권4호
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• pp.265-276
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• 2019

Patients with obstructive sleep apnea (OSA) whose phenotype belongs to a craniofacial vulnerability are referred from sleep doctors to orthodontists. In adults, for osseo-pharyngeal reconstruction (OPR) treatment, permanent maxillomandibular advancement (MMA) surgery and use of a temporary mandibular advancement device (MAD) are applied. This case report demonstrates successful treatment of OSA through application of phased MAD and MMA in a 16-year-old male with craniofacial deformity and residual growth potential. This patient showed skeletal and dentoalveolar changes after 7-year MAD use throughout post-adolescence, which affected the design and timing of subsequent MMA surgery, as well as post-surgical orthodontic strategy. This case report suggests that OPR treatment can be useful for treatment of OSA in post-adolescent patients, from an orthodontic point of view, in close collaboration with sleep doctors for interdisciplinary diagnosis and treatment.

• 대한토목학회논문집
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• 제32권4D호
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• pp.345-356
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• 2012

도로포장은 충족되어야 하는 서비스 수준을 유지하기 위해 반복적인 유지보수를 필요로 한다. 그러나 노후화된 하부구조와 반복적인 유지보수는 포장의 파손속도를 가속화시키기도 하며, 이는 한정된 예산의 효율성을 저해하는 요소가 될 수 있다. 따라서 본래의 기능을 유지하기 위해 도로의 재포장이 주기적으로 요구된다. 특히, 국도는 그 건설수요가 한계점에 다다랐으며, 노후로 인해 재포장 및 유지관리의 필요가 점점 증가하고 있는 시점이다. 그러나 도로관리자들은 예산의 한계로 이러한 노후포장에 대해 재포장 및 효율적인 유지관리를 시행하기에 많은 어려움을 겪고 있다. 이는 의사결정에 필요한 장기적인 유지보수 전략의 부재 때문이라 할 수 있다. 이에 본 논문은 반복적인 유지보수로 인한 포장의 상태변화를 고려한 유지보수 전략을 도출하여 관리자들의 의사결정에 도움을 주고자 하였다. 분석을 위해 포장관리시스템(PMS)이 도입된 1986년부터 장기간 누적된 국도의 유지보수 이력데이터를 활용하였으며, 방법론으로는 유지보수 횟수에 따른 수명분포 도출 및 위험률(hazard) 함수의 변화과정을 분석한 후, 이 결과를 근거로 다양한 유지보수 대안들에 대해 중장기 유지보수비용을 산정하였다. 이를 위해 포장파손과정의 불확실성을 고려하고, 도로관리자들에게 보다 실용적인 정보를 제공하기 위해 확률론적 방법(몬테카를로기법)을 추가로 도입하였다. 또한, 신뢰성 이론을 활용하여 유지보수에 대한 품질보증과 관련된 정보도 도출하고자 하였다. 이러한 정보는 장기유지보수전략 수립에 중요한 정보로 활용할 수 있다.

• Archives of Plastic Surgery
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• 제39권6호
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• pp.649-654
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• 2012

Background Deep burns of the elbow lead to soft tissue necrosis and infection, with exposure of deep structures. Adequate wound coverage of this area requires thin, pliable, and durable tissue, while optimal functional recovery requires early coverage and functional rehabilitation. We have found 3 types of island flaps that provide reliable coverage for the elbow. Methods A retrospective study was performed on all patients who underwent flap coverage of an elbow defect at our hospital. The patients' data including age, sex, cause of injury, wound dimensions, timing of flap coverage, postoperative elbow motion, and complications were investigated. Results Between 2001 and 2012, 16 patients were treated at our hospital. The mean age was 53.3 years. Three kinds of flaps were performed: 9 latissimus dorsi flaps, 4 lateral arm flaps, and 4 radial forearm flaps. The average defect size was 183.5 $cm^2$ (range, 28 to 670 cm2). Wound coverage was performed at mean duration of 45.9 days (range, 14 to 91 days). The mean postoperative active elbow flexion was $98^{\circ}$ (range, $85^{\circ}$ to $115^{\circ}$). Partial flap failure occurred in 1 latissimus dorsi flap. Minor complications included partial flap loss (11.8%), hematoma (23.5%), seroma (35.3%), and wound infection (5.9%). Conclusions Flap selection for elbow reconstruction is determined by the defect size and the extent of the adjacent tissue injury. Elbow reconstruction using an island flap is a single-staged, reliable, and relatively simple procedure that permits initiation of early rehabilitation, thereby improving a patient's functional outcome.

• 한국통신학회논문지
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• 제29권8C호
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• pp.1113-1124
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• 2004

본 논문에서는 입력 영상을 실시간으로 압축 및 복원할 수 있는 하드웨어(hardware, H/W)의 구조를 제안하고 처리되는 영상의 보안 및 보호를 위한 워터마킹 기법(watermarking)을 제안하여 H/W로 내장하고자 한다. 영상압축과 복원과정을 하나의 FPGA 칩 내에서 처리할 수 있도록 요구되는 모든 영상처리 요소를 고려하였고 VHDL(VHSIC Hardware Description Language)을 사용하여 각각을 효율적인 구조의 H/W로 사상하였다. 필터링과 양자화 과정을 거친 다음에 워터마킹을 수행하여 최소의 화질 감소를 가지고 양자화 과정에 의해 워터마크의 소실이 없으면서 실시간으로 동작이 가능하도록 하였다. 구현된 하드웨어는 크게 데이터 패스부(data path part)와 제어부(Main Controller, Memory Controller)로 구분되고 데이터 패스부는 영상처리 블록과 데이터처리 블록으로 나누어진다. H/W 구현을 위해 알고리즘의 기능적인 간략화를 고려하여 H/W의 구조에 반영하였다. 동작은 크게 영상의 압축과 복원과정으로 구분되고 영상의 압축 시 대기지연 시간 없이 워터마킹이 수행되며 전체 동작은 A/D 변환기에 동기하여 필드단위의 동작을 수행한다. 구현된 H/W는 APEX20KC EP20K600CB652-7 FPGA 칩에서 69%(16980개)의 LAB(Logic Array Block)와 9%(28352개)의 ESB(Embedded System Block)을 사용하였고 최대 약 82MHz의 클록주파수에서 안정적으로 동작할 수 있어 초당 67필드(33 프레임)의 영상에 대해 워터마킹과 압축을 실시간으로 수행할 수 있었다.

• The Journal of Advanced Prosthodontics
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• 제8권5호
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• pp.363-371
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• 2016

PURPOSE. On maxillofacial tumor patients, oral implant placement prior to postoperative radiotherapy can shorten the period of prosthetic reconstruction. There is still lack of research on effects of post-implant radiotherapy such as healing process or loading time, which is important for prosthodontic treatment planning. Therefore, this study evaluated the effects of post-implant local irradiation on the osseointegration of implants during different healing stages. MATERIALS AND METHODS. Custom-made implants were placed bilaterally on maxillary posterior edentulous area 4 weeks after extraction of the maxillary first molars in Forty-eight Sprague-Dawley rats. Experimental group (exp.) received radiation after implant surgery and the other group (control) didn't. Each group was divided into three sub-groups according to the healing time (2, 4, and 8 week) from implant placement. The exp. group 1, 2 received 15-Gy radiation 1 day after implant placement (immediate irradiation). The exp. group 3 received 15-Gy radiation 4 weeks after implant placement (delayed irradiation). RESULTS. The bone mineral density (BMD) was significantly lower in the immediate irradiation groups. BMD was similar in the delayed irradiation group and the control group. The irradiated groups exhibited a lower bone-to-implant contact ratio, although the difference was not statistically significant. The irradiated groups also exhibited a significantly lower bone volume and higher empty lacuna count than the control groups. No implant failure due to local irradiation was found in this study. CONCLUSION. Within the limits of this study, the timing of local irradiation critically influences the bone healing mechanism, which is related to loading time of prostheses.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제29권4호
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• pp.333-339
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• 2007

Adequate bone quantity is one of the important factor to obtain osseointegration after implantation. Guided bone regeneration (GBR) has widely used in implantation for reconstruction of bony defects. Since introducing this procedure, there are many studies about survival rate of implants, changing in surrounding bone volume after function. The purpose of this study was to evaluate the amount of resorption according to placement timing and survival rate after function. The subjects were patients who had been operated with GBR from Jun 2003 to Jun 2004 in Seoul National University Bundang Hospital. They were divided into simultaneous and delayed placement group. The follow up had been performed at the time of just after GBR, 1, 3, 6, 12, 24-month later and standard periapical radiographs were taken to estimate the bone level at the time. The total average of bone level change in radiographs was 1.94mm(${\pm}0.25$), and 1.92mm(${\pm}0.72$) in simultaneous installation, 2.03mm(${\pm}0.25$) in delayed installation. In this report, the survival rates were 92.2% in simulataneous group and 92.3% in delayed group. Insufficient primary stability, early contamination of wound, overloading, poor oral hygiene, and infection were thought to be associated factors in the failed cases.

• Archives of Plastic Surgery
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• 제44권5호
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• pp.370-377
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• 2017

Background Composite grafts are frequently used for facial reconstruction. However, the unpredictability of the results and difficulties with large defects are disadvantages. Adipose-derived stem cells (ADSCs) express several cytokines, and increase the survival of random flaps and fat grafts owing to their angiogenic potential. Methods This study investigated composite graft survival after ADSC injection. Circular chondrocutaneous composite tissues, 2 cm in diameter, from 15 New Zealand white rabbits were used. Thirty ears were randomly divided into 3 groups. In the experimental groups (1 and 2), ADSCs were subcutaneously injected 7 days and immediately before the operation, respectively. Similarly, phosphate-buffered saline was injected in the control group just before surgery in the same manner as in group 2. In all groups, chondrocutaneous composite tissue was elevated, rotated 90 degrees, and repaired in its original position. Skin flow was assessed using laser Doppler 1, 3, 6, 9, and 12 days after surgery. At 1 and 12 days after surgery, the viable area was assessed using digital photography; the rabbits were euthanized, and immunohistochemical staining for CD31 was performed to assess neovascularization. Results The survival of composite grafts increased significantly with the injection of ADSCs (P<0.05). ADSC injection significantly improved neovascularization based on anti-CD31 immunohistochemical analysis and vascular endothelial growth factor expression (P<0.05) in both group 1 and group 2 compared to the control group. No statistically significant differences in graft survival, anti-CD31 neovascularization, or microcirculation were found between groups 1 and 2. Conclusions Treatment with ADSCs improved the composite graft survival, as confirmed by the survival area and histological evaluation. The differences according to the injection timing were not significant.