• Archives of Plastic Surgery
• /
• 제36권5호
• /
• pp.649-653
• /
• 2009

Purpose: Double - eyelid operation is one of the most common cosmetic operations among Korean patients. In such operations, however, the complexity of and individual differences in the patients' anatomical structures may cause various complications, such as asymmetry, retraction of the eyelid, and the occurrence of a high fold. A high fold occurs frequently, and its correction is not very simple. Many methods have been developed to correct it, and among these, the operation involving the excision of the skin between the previous double - eyelid line and the new double - eyelid line is usually selected by plastic surgeons. In many cases, however, patients have insufficient eyelid skins for this operation. In this study, the authors introduce an operation procedure for high - fold correction that does not involve skin excision Methods: From June 2005 to June 2009, 246 cases were treated with this procedure. After the incision of the new double - eyelid line, dissection was done between the previous scar tissue and the levator aponeurosis. Then the orbital septum, orbital fat or the retro - orbicularis oculi fat was slid down and sutured with a tarsal plate. Such sutures were repeated at four to five points, including the lateral and medial limbus, to prevent the reattachment of the previous scar and to create a new double - eyelid line at the end of the orbital septum. Results: Most of the high - fold patients were satisfied with the procedure described above. Their previous scar was hidden under the new double - eyelid line after the operation. In the six cases, the scar was visible in the patients who had a very high and deep inner line. As such, scar revision was undertaken three months after the operation. It is known that scar revision is also required after an operation involving skin excision in the case of a very high inner - eyelid line. Conclusion: This method is an appropriative procedure for high - fold correction for patients who have insufficient upper - eyelid skin.

• 한국인터넷방송통신학회논문지
• /
• 제9권3호
• /
• pp.193-199
• /
• 2009

전력선 통신(PLC : Power Line Communication) 기술은 유선 액세스 네트워크 솔류션 중 높은 잠재력을 갖고 있는 후보로서 논의되고 있다. 본 논문에서는 PLC 채널에서 이중 이진 터보 부호(DBTC : Double Binary Turbo Code) 성능에 대해 연구하였다. PLC 채널 환경을 만들기 위해 Bernoulli-Gaussian 잡음을 고려하였다. 시스템 성능은 비트 오류 확률 측면에서 분석되었다. 실험 결과로부터 이중 이진 터보 부호화는 상당한 부호화 이득을 제공하는 것을 확인할 수 있었다. 또한 터보 복호 과정에서 복호 횟수를 증가시킴에 따라서 시스템 성능이 향상되는 것을 확인할 수 있었다.

• 제어로봇시스템학회:학술대회논문집
• /
• 제어로봇시스템학회 2001년도 ICCAS
• /
• pp.73.4-73
• /
• 2001

We suggest a system to detection whether material picked up is double or single when the robot feeds them in automation line. This system measures thickness of metal plate and alarms when they are double sheet measuring boundary lines of metal sheet. This system calculates the minimum distance of straight boundary lines by eliminating noise in the edge regions. In the experimental system, double or single is determined by calculating implemented the thickness in the image where the distance of pixels are retrieved by the hash table. In this paper, the algorithm of histogram is adapted to experiment in the implement, thus proved as double sheet detection system.

• Design & Manufacturing
• /
• 제10권2호
• /
• pp.39-43
• /
• 2016

Most of automobile parts manufactured through sheet metal forming are mass-produced by using press mold. In recent years, automation and speeding up of press lines have been expanding to maximize product productivity using a press die. The proportion of the moving time in the press line is high, and therefore requires high-speed and automated equipment for the moving process. In this paper, to provide the double-moving system can be the moving time reduction and increased productivity. Developed transport system consists of the material supply, the material feeding device and the PLC controller and the devices are positioned between each of the pressing process. In this paper, the double-moving system including developed units using a multi-axial single-acting through this reduced the C/T(cycle time) and improved the productivity.

• 한국초등수학교육학회지
• /
• 제20권3호
• /
• pp.431-456
• /
• 2016

본 연구는 수직선의 적절한 도입 시기와 활용 방법을 탐구하여 초등학생들의 수개념 학습 지도를 위한 시사점을 제공하고자 하였다. 이를 위하여 수 개념 형성을 위한 수학적 모델인 수직선, 빈 수직선, 이중 수직선과 수 세기와 수 개념의 발달유형에 대하여 고찰하였고, 실제 초등학생들의 수직선 도입 시기와 활용 방법에 대한 사례 연구 결과를 분석하였다. 첫째, 수직선 도입을 2학년부터 실시하여 수직선의 은유적 개념에 대한 이해를 통해 이어지는 수 개념 학습에 도움이 될 수 있도록 조정할 필요가 있다. 둘째, 덧셈과 뺄셈과 같은 연산과정에서 다양한 사고 전략을 시각적으로 그려낼 수 있는 수학적 모델인 빈 수직선과 곱셈적 비교 상황이나 나눗셈이 이루어지는 상황인 등분제와 포함제, 비율이나 비례배분의 이해를 위한 시각적 모델인 이중 수직선을 적극적으로 도입하고 활용할 필요가 있다. 셋째, 수직선이나 빈 수직선, 이중 수직선을 도입할 때, 수직선의 은유적 개념을 충분히 이해할 수 있도록 구체적인 안내와 활용 방법에 대한 학습의 필요성을 제안하였다.

• Journal of Electrical Engineering and Technology
• /
• 제6권1호
• /
• pp.1-7
• /
• 2011

This paper proposes an enhanced noise robust algorithm for fault location on double-circuit transmission line for the case of single line-to-ground (SLG) fault, which uses distributed parameter line model that also considers the mutual coupling effect. The proposed algorithm requires the voltages and currents from single-terminal data only and does not require adjacent circuit current data. The fault distance can be simply determined by solving a second-order polynomial equation, which is achieved directly through the analysis of the circuit. The algorithm, which employs the faulted phase network and zero-sequence network with source impedance involved, effectively eliminates the effect of load flow and fault resistance on the accuracy of fault location. The proposed algorithm is tested using MATLAB/Simulink under different fault locations and shows high accuracy. The uncertainty of source impedance and the measurement errors are also included in the simulation and shows that the algorithm has high robustness.

• Journal of Electrical Engineering and Technology
• /
• 제11권4호
• /
• pp.921-930
• /
• 2016

This paper proposes a design and control method for a high-voltage direction current modular multilevel converter (HVDC-MMC) considering the capacitor voltage ripple of the submodule (SM). The capacitor voltage ripple consists of the line frequency and double-line-frequency components. The double line- frequency component does not fluctuate according to the active power, whereas the line-frequency component is highly influenced by the grid-side voltage and current. If the grid voltage drops, a conventional converter increases the current to maintain the active power. A grid voltage drops, current increment, or both occur with a capacitor voltage ripple higher than the limit value. In order to reliably control an MMC within a limit value, the SM capacitor should be designed on the basis of the capacitor voltage ripple. In this paper, the capacitor voltage ripple according to the grid voltage and current are analyzed, and the proposed control method includes a current limitation method considering the capacitor voltage ripple. The proposed design and control method are verified through simulation using PSCAD/EMTDC.

• 한국정보통신학회논문지
• /
• 제20권3호
• /
• pp.457-463
• /
• 2016

본 논문에서는 변형된 내장형 밸런을 사용하여 이중 다이폴 준-야기 안테나(double-dipole quasi-Yagi antenna; DDQYA)의 대역폭을 향상하는 방법에 대하여 연구하였다. 변형된 내장형 밸런은 동일면 스트립 선로의 중앙으로 삽입된 마이크로스트립 선로로 구성되며, 마이크로스트립 선로의 끝은 급전점에서 단락 핀으로 동일면 스트립 선로와 연결되어 있다. 변형된 내장형 밸런의 구조는 DDQYA의 대역폭을 향상시키기 위해 조정하였다. 또한, 제안된 밸런의 back-to-back 구조에서의 성능을 기존 밸런과 비교하였다. 최적화된 변형된 내장형 밸런을 가진 DDQYA 안테나를 FR4 기판 상에 제작하고 특성을 실험한 결과 전압 정재파비(voltage standing wave ratio; VSWR) < 2 이하인 대역은 1.56-3.04 GHz(64.4%)이고, 대역폭이 기존의 밸런을 가진 DDQYA에 비해 증가함을 확인하였다.

• 공학기술논문지
• /
• 제7권3호
• /
• pp.131-135
• /
• 2014

In this paper was proposed a flux offset-type fault current limiter as means of reducing fault currents. To secure the operation reliability of a flux offset-type fault current limiter, constructed a simulation system to analyze its operation characteristics by generating a double line-to-line fault. According to the test results, the system performed stably without any impedance. However, when an accident occurred, the flux-offset of magnetic was not occurred. Because of this, any impedance occurred at circuit. It was confirmed that the impedance was low and fast to limit the fault current. At this time, the fault current limited rate was about 95%.

• Journal of Electrical Engineering and Technology
• /
• 제10권3호
• /
• pp.1081-1085
• /
• 2015

In this paper a printed pair dipole antenna with double tapered microstrip balun for wireless communications is proposed. The proposed antenna consists of a pair arm of different sizes that is branched microstrip line and microstrip line with the ground plane on opposite side of the dielectric substrate plane. The proposed antenna is matched between the ground plane to the microstrip line by double tapered microstrip balun. This antenna obtains multi-band radiation frequency band. The impedance bandwidths for a reflection coefficient of VSWR ≤ 2 are about 1.01 GHz (2.35~3.336 GHz), 1.56 GHz (4.7~6.26 GHz) and 1.15GHz (6.85~8.0[GHz]). Additionally, the measurement peak gain is about 3.6 dBi. The proposed antenna is able to support wireless communication applications.