• 한국우주과학회:학술대회논문집(한국우주과학회보)
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• 한국우주과학회 2007년도 한국우주과학회보 제16권2호
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• pp.55-55
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• 2007

• 한국우주과학회:학술대회논문집(한국우주과학회보)
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• 한국우주과학회 2007년도 한국우주과학회보 제16권1호
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• pp.49-49
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• 2007

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2001년도 하계종합학술대회 논문집(1)
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• pp.29-32
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• 2001

This paper has simulated the PER(Packet Error Rate), ratio of received packet and payload BER of Bluetooth system with packet types of ACL(Asynchronous Connection Less) and SCO(Synchronous Connection Oriented) link over wireless Ad-hoc environment. AWGN(Additive White Gaussian Noise) and Rayleigh fading are considered as channel model, and the analysis is based on the baseband model of Bluetooth system. In terms of PER and ratio of received packet, performance of DM1 packet is almost same as those of HV1, HV2 and HV3 packets, the performances of the other packets depend on the packet types. In terms of payload BER performance, there is no difference among HV2 packet of SCO link and DM1, DM3, DM5 packets of ACL link. Moreover, there is no difference among HV3 packet of SCO link and DM1, DM3, DM5 packets of ACL link, too.

• 대한관절경학회지
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• 제1권1호
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• pp.72-80
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• 1997

Numerous techniques of anterior cruciate ligament (ACL) reconstruction have been described in literature. All have inherent advantages and disadvantages. The central one-third patellar tendon and hamstring tendons are the most commonly used autogenous tissues for replacement of a torn anterior cruciate ligament. Although the central one-third patellar tendon is considered to be 'the gold standard' for replacement of torn ACL. equivalent results have been reported using hamstring tendon grafts. Autogenous hamstring grafts provide adequate strength while avoiding donor site morbidity associated with bone-tendon-bone harvest. $EndoButton^{\circledR}$ femoral fixation allows precise femoral tunnel placement without a second incison. The purpose of this article is to describe surgical techniques using a quadrupled semitendinosus tendon and $EndoButton^{\circledR}$ fixation, and review the results of replacement of ACL.

• 대한기계학회논문집A
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• 제30권4호
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• pp.435-441
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• 2006

The anterior cruciate ligament(ACL) is an important stabilizer of knee joint. The ACL injury of knee is common and a serious ACL injury leads to ligament reconstruction surgery. Gait analysis is essential to identify knee condition of patients who display abnormal gait. The purpose of this study is to evaluate and classify knee condition of ACL deficient patients using a nonlinear dynamic method. The nonlinear method focuses on understanding how variations in the gait pattern change over time. The experiments were carried out for 17 subjects(l2 healthy subjects and five subjects with unilateral deficiency) walking on a motorized treadmill for 100 seconds. Three dimensional kinematics of the lower extremity were collected by using four cameras and KWON 3D motion analysis system. The largest Lyapunov exponent calculated from knee joint flexion-extension time series was used to quantify knee stability. The results revealed the difference between healthy subjects and patients. The deficient knee was significantly unstable compared with the contralateral knee. This study suggests an evaluation scheme of the severity of injury and the level of recovery. The proposed Lyapunov exponent can be used in rehabilitation and diagnosis of recoverable patients.

• 대한관절경학회지
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• 제1권1호
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• pp.1-8
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• 1997

The anterior cruciate ligament(ACL) is, perhaps, the most intriguing component of the knee joint. Initially referred to crucial ligament because of the cruciate or crossed arrangement or the anterior and posterior ligaments within the knee. the irony or the ACL being crucial to the well-being or the joint has only recently appreciated. The anterior cruciate ligament of human knee joint is a complex structure and its orientation, construct and biology arc directly related to the knee function as a constraint of knee joint motion. In addition to its functional role as a static stabilizer or the knee. the ACL has a unique neurovascular system. The vascular anatomy of the ACL plays a crucial role in the repair and reconstruction of the ligament, and the neuroreceptors found in its substance suggest a possible proprioceptive role for the ligament. The structural complexity of the ACL allows the ligament to function through the normal range of motion as a static stabilizer or the knee. hut it also makes the exact duplication of this structure very difficult. A comprehensive knowledge or the anatomy of the ACL can provide the orthopedic surgeon with a blueprint for the idealized repair and reconstruction of this most complex structure.

• 대한관절경학회지
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• 제1권1호
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• pp.47-51
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• 1997

A torn anterior cruciate ligament(ACL) is the most common serious ligamentous injury to the knee joint. The incidence of ACL tears seems to be increasing, at least partly as a result of the increasing participation of individuals of all ages in high-risk sports. The most commonly used graft source for ACL reconstruction is the autogenous bone-patellar tendon-bone graft unit. Despite a good success record. postoperative complications, such as infection, patellar contracture/patellar baja, patellar fracture, rupture of the patellar tendon, graft failure without reinjury, can occur following ACL surgery. The purpose of this paper is to provide guidelines regarding the key points of the reconstructive procedure in a sequence and how to prevent or minimize the complications that can follow ACL reconstructive surgery. We want this knowledge can help orthopaedic surgeons to understand the reasons for previous and current successes and failures of reconstruction of the ACL, and it can help them to plan the care of patients who have an injury of the ligament.

• 대한관절경학회지
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• 제1권1호
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• pp.66-71
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• 1997

The all inside anterior cruciate ligament reconstruction technique places an anterior ligament substitutes within two bony sockets rather than hone tunnel. This approach is accomplished through arthroscopic three portal which avoids the surgical exposure and morbidity associated with creating traditional bone tunnel. This technique has several distinct advantages when compared with the traditional ACL reconstruction through the bone tunnels. It offers the surgeon a less morbid method for ACL reconstruction that positions an ACL substitute at the anatomic attachment sites of the original ACL with two bone sockets, obviating the need for traditional bone tunnels. Graft fixation at or near the anatomic attachment points of the original ACL minimizes creep with early range of motion and reduces the abrasive 'wind-shield wipe' motion of the graft which occur with bone plugs positioned inside bone tunnels. The sagittal posterior angle to the tibial socket increases fixation strength to pullout with anterior translation force for the tibia on the femur. This technique is not graft specific and can accomodate any graft in which graft length can be customized to the intraarticular native ACL length.

• 대한정형외과스포츠의학회지
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• 제2권2호
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• pp.92-99
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• 2003

스포츠 활동과 사고로 인하여 전방십자인대 재건술이 많이 증가하고 있으며 여러 종류의 자가 및 동종이식건이 많이 사용되어지고 있다. 자가 골-슬개건-골을 이용한 전방십자인대 재건술이 제일 대표적인 이식건으로 사용되고 있으나 공여부의 합병증과 전방슬관절통 등의 문제가 발생될 수 있으며 환자에 따라서 이러한 문제를 줄일 수 있는 다른 이식건의 사용도 필요할 수 있다. 여러 이식건의 생역학적인 특성, 장점 및 단점, 합병증을 충분히 이해함으로써 환자 개인에 맞는 적절한 이식건을 선택할 수 있으며 수술후 환자의 만족도를 높일 수 있을 것으로 생각된다

• 대한관절경학회지
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• 제10권1호
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• pp.39-44
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• 2006

목적: 전방 십자 인대 손상군과 슬관절의 손상 경력이 없는 정상군에서 슬개골 저위증의 빈도와 그 정도를 비교하고자 한다. 대상 및 방법: 스포츠 손상 후 발생한 전방 십자 인대 파열로 전방 십자 인대 재건술을 시행한 114예를 대상으로 하였다. 제 I 군은 수상 후 3주 이내에 자기공명영상을 시행한 급성 전방 십자 인대 파열군으로, 제 II 군은 3주 이후에 자기공명영상을 시행한 만성 전방 십자 인대 파열군으로, 제 III 군은 정상 대조군으로 하였다. T1 강조 자기 공명영상 정중 시상면에서 Insall-Salvati ratio, Carton index를 측정하여 비교 분석하였다. 결과: 정상군에서 Insall-Salvati ratio는 $1.02{\pm}0.12$, Carton index는 $1.14{\pm}0.16$, 전방 십자 인대 파열군에서는 각각 $0.91{\pm}0.12,\;0.89{\pm}0.20$으로 전방 십자 인대 파열군에서 모두 통계학적으로 유의하게 적었다. 급성 전방 십자 인대 파열군과 만성 전방 십자 인대 파열군에서의 비교는 통계학적 유의성은 없었다. 결론: 전방 십자 인대 파열군에서 정상 대조군과 비교시 슬개골 저위증의 경향을 보였으며, 따라서 전방 십자 인대 재건술시 슬개골 저위증의 경우, 이식건의 선택에 있어 세심한 고려가 필요할 것으로 사료된다.