수근관증후군의 수술방법에 따른 성적 - 내시경수술과 개방절개술 -

이한영,김일만,이장철,이창영,손은익,김동원,임만빈,Lee, Han Young,Kim, Il-Man,Lee, Jang Chull,Lee, Chang Young,Son, Eun Ik,Kim, Dong Won,Yim, Man Bin 대한신경외과학회 2000 Journal of Korean neurosurgical society Vol.29 No.11

Objective : The goal of this study is to present whether endoscopic release(ER) is superior to open release(OR) for the treatment of carpal tunnel syndrome(CTS). Method and Material : Fifty-nine wrists in 43 patients who had clnical signs and symptoms consistent with CTS, not responded to non-operative management, were entered into the study. Authors retrospectively compared 27 wrists treated with ER(February 1999-June 1999) with 32 wrists treated with OR(October 1997-March 1999). We performed conventional open surgery in 25 patients(mean age ; 46 years) and Brown's two-portal technique in 18 patients(mean age ; 53 years) under intravenous regional block or general anesthesia. Results : Sixteen patients had CTS on both hands and left hands were affected more frequently than right hand, 34 and 25 respectively. Successful and poor results of ER were similar to those of OR. For patients in OR group, mean duration of symptoms was 5 years(range 1 month-30 years), and postoperative outcome was good in 27(84.4%) of wrists and poor in 5(15.6%). For patients in ER group, mean duration of symptoms was 7 months (range 2 months-25 years), outcome was good in 23(85.2%) of wrists and poor in 4(14.8%). The average time for complete relief of pain was 1.3 weeks and 7.6 weeks, respectively for OR and ER groups. No complication was noted in either group. Conclusion : This preliminary analysis suggests that faster relief of pain was achieved when the endoscopic method was used, although there were no significant differences in their efficacies regarding the improvement of symptoms.

말초신경질환에서 자기공명영상의 진단적 가치

이한영,이장철,김일만,이창영,손은익,김동원,임만빈,Lee, Han Young,Lee, Jang Chull,Kim, Il-Man,Lee, Chang-Young,Ikm, Eun,Kim, Dong Won,Yim, Man Bin 대한신경외과학회 2001 Journal of Korean neurosurgical society Vol.30 No.9

Objective : The development of magnetic resonance neurography(MRN) has made it possible to produce highresolution images of peripheral nerves themselves, as well as associated intraneural and extraneural lesions. We evaluated the clinical application and utility of high-resolution MRN techniques for the diagnosis and treatment of a variety of peripheral nerve disorder(PND)s. Material and Method : MRN images were obtained using T1-weighted spin echo, T2-weighted fast spin echo with fat suppression, and short tau inversion recovery(STIR) fast spin-echo pulse sequences. Fifteen patients were studied, three with brachial plexus tumors, five with chronic entrapment syndromes, and seven with traumatic peripheral lesions. Ten patients underwent surgery. Results : In MRN with STIR sequences of axial and coronal imagings, signals of the peripheral nerves with various lesions were detected as fairly bright signals and were discerned from signals of the uninvolved nerves. Increased signal with proximal swelling and distal flattening of the median nerve were seen in all patients of carpal tunnel syndrome. Among the eight patients with brachial plexus injury or tumors, T2-weighted MRN showed increased signal intensity in involved roots in five, enhanced mass lesions in three, and traumatic pseudomeningocele in three. Other associated MRI findings were adjacent bony signal change, neuroma, root adhesion and denervated muscle atophy with signal change. Conclusion : MRN with high-resolution imaging can be useful in the preoperative evaluation and surgical planning in patients with peripheral nerve lesions.

광대역 이중편파 무선 중계기용 패치안테나 설계 및 제작

이한영,Lee, Han-Young 한국전자통신학회 2012 한국전자통신학회 논문지 Vol.7 No.6

본 논문에서는 주파수 1.525GHz~1.665GHz 넓은 대역에서 동작하는 이중편파 패치안테나를 설계 및 제작하였다. 넓은 대역폭 및 고 이득을 갖기 위해 GND기판으로 부터 Air층을 높게 적용하였으며, 광대역 축비 및 고 이득을 갖기 위해 기생패치를 적용하여 원하는 데이터를 얻을 수 있도록 하였다. 그 결과 안테나의 정재파비(VSWR)는 전 대역에서 1.9 이하를 나타내며, 반사손실 S11과 S22는 전 대역에서 -10dB이하로 시뮬레이션과 유사한 특성 결과를 얻었다. LHCP(Left Hand Circular Polarization) 및 RHCP(Right Hand Circular Polarization)의 격리 특성은 시뮬레이션 특성보다 더 개선되어 전 대역에서 -13dB이하로 만족한 결과를 얻었다. In this paper, a dual polarization patch antenna operates at the wide bandwidth of 1.525GHz~1.665GHz was designed and fabricated. To obtain the wide bandwidth and high gain, increased height of air floor from GND was applied, and to get wide band axial ratio and high gain, parasitic patch was applied. The simulation and measurement showed good agreements, the VSWR was less than 1.9 at the frequency bandwidth, the return loss was less than -10dB, and the LHCP(Left Hand Circular Polarization) and RHCP(Right Hand Circular Polarization) isolation was less than -13dB at the frequency bandwidth.

유동상열처리로에 의해 BORIDING처리한 철강재료의 미끄럼마모특성연구

이한영,배석천( Han Young Lee,Seok Choun Bae ) 한국열처리공학회 1996 熱處理工學會誌 Vol.9 No.4

Boriding is one of the chemical methods to achieve the case hardening of steel as well as nitriding or carburizing. The surface layer of the bonded steel shows higher hardness and exhibits better resistance to corrosion or fatigue than the nitrided or carburized steel. The great majority of previous studies were confined to mild steel or some alloy steel. To enlarge the application, ductile cast iron (DCI) as a material for bonding has been tried in this study. Thus, sliding wear test has conducted using a pin-on-disc machine to compare between borided DCI and mild steel in fluidized bed furnace. The results show that the wear resistance of borided DCI is improved. Especially it is more efficient in the case of occurence of the mechanical wear.

ATM 망에서 웨이브릿 변환을 이용한 계층부호화 영상 전송에 관한 연구

이한영,송재연,Lee, Han-Young,Song, Jae-Youn 대한전자공학회 1998 電子工學會論文誌-T Vol.t35 No.2

ATM 기술과 패킷망의 발전에 따라 음성, 데이터, 영상 전송의 필요성이 증가되고 있다. ATM에서는 데이타 손실을 최소화하기 위하여 셀로 불리우는 일정길이의 데이타로 나누어 진다. ATM에서는 송신시 부호를 고정하지 않고 버리기 때문에 영상신호 전송에서는 계층부호화 방법을 사용한다. 따라서 본 논문에서는 계층부호화 방법인 웨이브릿 변환을 이용한 부호화를 시뮬레이션 하였다. We need the packet transmission of voice, data and video according to the development of ATM technology and packet network. In ATM, packet is parted to the constant length data, we called cell, the method is needed to minimize data loss. Because over ATM, we discard error cell without correction in transmission. So, about video, there is layered coding method. We simulated the coding using wavelet transform, which is structurally layed coded, so need not the additional coder.

능동형 RFID시스템에서 태그 인식 속도 향상을 위한 고속 태그 충돌 방지 알고리즘

이한영,Lee, Han-Young 한국전자통신학회 2012 한국전자통신학회 논문지 Vol.7 No.2

현재 RFID 시스템에서 해결하여야 할 가장 큰 문제 중 하나는 태그간의 충돌로 인해 인식 효율이 떨어진다는 것이다. 기존의 충돌 방식 중 BS 충돌 방지 알고리즘 방식은 구현이 간단하다는 장점이 있으나, 태그 수가 많아짐에 따라서 태그간 충돌에 의해 전체 태그를 읽는데 요구되는 단계별 스케줄 횟수가 증가하는 단점을 가지고 있다. 본 논문에서는 이 문제를 해결하기 위해서 충돌 예상을 최소화 하기 위해 사전에 '0'과 '1'의 결정 비트를 통해 복수의 응답 프레임(MF)을 제안한 방식을 제안하였다. 시뮬레이션 결과 복수 응답 프레임 (MF) 알고리즘은 기존의 알고리즘보다 30~50% 성능이 향상됨을 보인다는 것을 알 수 있었다. In RFID System, one of the problem that we must slove is to devise a good anti-collision algorithms to improve the efficiency of tag identification which is usually low because of tag collision. Among of the existing RFID anti-collision algorithm, BS (Binary Search) algorithm, though simple, has a disadvantage that the stage of times used to identify the tags increase exponentially as the number of tags does. In this paper, I propose a new anti-collision algorithm called Multi-collision reflected frame which restricts the number of stages and decided bit. Since the proposal algorithm keep the length size of UID and density of total tag when have 100%. The simulation results showed that the proposed algorithm improves the efficiency by 30~50% compared to the existing algorithm.

중복 변화하는 미끄럼 속도에서의 마모 거동

이한영(Han-Young Lee),박원규(Won-Kyu Park) 한국트라이볼로지학회 2010 한국트라이볼로지학회 학술대회 Vol.2010 No.11

자동차 클러치 Diaphragm용 PTFE 코팅층의 미끄럼 마찰마모특성

이한영(Han-Young Lee),김태준(Tae-Jun Kim),조용재(Yong-Jae Cho),허만대(Man-Dae Hur) 한국트라이볼로지학회 2006 한국트라이볼로지학회 학술대회 Vol.2006 No.6

Diaphragm as a substitute for the role of clutch facing is contacted with primary wheel cover in newly designed clutch system. PTFE films have been coated on the diaphragm surface to control their friction properties. In this context, sliding wear and friction properties of the PTFE coating layer might have a great influence on performance of the clutch system. In this study, the effect of the size and its uniformity of raw powder for PTFE coating on sliding wear and friction properties were investigated. As a results, PTFE layer coated using the raw powder with small and uniform size has better wear resistance. This is considered that because the coating layer would have denser microstructure with a little amorphous in view of the lower melting point due to large surface area. And their friction coefficient becomes decrease at low sliding speed when the surface of counter material is smooth.

전력증폭부의 광대역 특성 개선을 위한 최적의 부하 임피던스 설계 방안 연구

이한영(Han-Young Lee) 대한전기학회 2009 전기학회논문지 Vol.58 No.6

In this paper, we studied on the power amplifier which has the output of the optimal to 100㎒-2㎓ band. Optimal output power match was fabricated using the two types; one is the linear tapering and the other is the impedance transformer. In the case of output power match using linear tapering, output power was 35.35㏈m at 2㎓ and 31.41㏈m at 100㎒. The other case of output match using impedance transformer, output power was 34.8㏈m at 2㎓ and 33.25㏈m at 100㎒. Comparison of the results in the two cases, impedance transformer type present the improved results by 1.84㏈ of output power.

알루미늄 합금의 미끄럼마모 특성에 미치는 상대재 경도의 영향

이한영(Han-Young Lee),조용재(Yong-Jae Cho),김태준(Tae-Jun Kim),박원규(Won-Kyu Park) 한국트라이볼로지학회 2010 한국윤활학회지(윤활학회지) Vol.26 No.2

In order to investigate the wear behavior of aluminum alloy depended on different hardness of the mating tool steel, sliding wear tests were conducted. It was found that the wear characteristics pattern of aluminum alloy for sliding speed was not affected by the hardness of the mating tool steel. However, the effects of the hardness of the mating tool steel exhibited only in relatively low sliding speed ranges. At these ranges, the wear rate of aluminum alloy decreased when increasing the hardness of the mating tool steel. This was attributed by the fact that Al₂O₃ particles released from the aluminum worn surface were crushed and embedded on the mating worn surface with high hardness level. At the high sliding speed ranges, wear of aluminum alloy was hardly occurred by the formation of thick Al₂O₃ film on the worn surface, regardless of the hardness of the mating tool steel.