• 제목/요약/키워드: 여승

검색결과 106건 처리시간 0.021초

후두격막의 새로운 치료법 (A New Surgical Technique of the Larygeal Web)

  • 안회영;여승근;박창식;이동엽;차창일
    • 대한기관식도과학회:학술대회논문집
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    • 대한기관식도과학회 1993년도 제27차 학술대회 초록집
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    • pp.77-77
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    • 1993
  • 후두격막은 여러가지 원인으로 생기나 선천성의 경우를 제외하고는 비교적 두텁고 질긴 반흔 조직으로 그 상하면은 상피세포로 덮여 있다. 후두격막 치료의 궁극적 목표는 양측 성대의 전장이 상피 세포로 덮여져서 호흡 및 발성의 정상 기능을 찾게 하는 데 있다. 저자들은 최근 6예의 후두격막 환자에서 전신 경구삽관 마취하에 미세수술로 격막을 전후로 절개한 후 절개면의 상-하 상피층을 봉합하는 새로운 수술 방법을 고안하여 시도하였다. 보통의 후두미세술과 같이 익숙한 장비와 수술시야에서 격막 이외의 다른 부위에 손상을 주지 않고, 비교적 짧은 수술 시간 내에 한번의 수술로 별다른 합병증이 없고, 입원 시간도 짧은 등 장점이 있는 후두격막에 효과적인 치료법으로 생각되어 소개한다.

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대형 디젤 엔진 터보차져 고주파 소음에 관한 연구 (Investigation on Turbocharger Whine Noise in a Heavy-duty Diesel Engine)

  • 최성배;정용진;여승동
    • 한국음향학회:학술대회논문집
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    • 한국음향학회 2000년도 학술발표대회 논문집 제19권 2호
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    • pp.235-238
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    • 2000
  • Current diesel engines are usually equipped with turbochargers for improving fuel economy as well as meeting more stringent emission regulations. These turbochargers usually cause noise problems because they spins vey high such as 100,000 to 200,000 rpm, These noises are largely divided into whistle and whine noises. The frequency of whistle noise corresponds to their rotation speed, and the frequency of whine noise does to the multiplication of their rotation speed and the number of compressor blades. Turbocharger manufacturers developed a special type of compressor, effectively compressing air sucked from a duct; Recirculation Compressor Cover (RCC) or Map Width Enhancement (MWE). This special structure improves turbocharger's capability by expanding compressor's working area, but it seriously causes a noise problem, whine noise. There were many trials to surpress the noise occurred inside a compressor such as modification of a compressor, noise baffles or secondary measurements. However, it was currently concluded that the whine noise caused by the special compressor can not be reduced to that done by a standard compressor, and the strength difference of whine noises between the two compressors is not negligible. Thus, the standard compressor is decided to be applied to a newly developing heavy-duty diesel engine in order to resolve the turbocharger noise problem with a stiffened suction duct directly connected to a compressor.

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4륜구동 직렬형 하이브리드 전기추진시스템의 구성품 용량 최적화 연구 (A Study on Optimization of Components Sizing for 4×4 Series Hybrid Electric Propulsion Systems)

  • 장명언;정순규;한규홍;여승태
    • 한국군사과학기술학회지
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    • 제17권2호
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    • pp.159-166
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    • 2014
  • The study is conducted on the subject of optimization of components sizing for series hybrid electric propulsion systems. The components sizing of series type hybrid system is very important because each component of series type is larger than the corresponding component of the parallel type or series-parallel type. If the components sizing is greater or less than what is required to this system, the performance of the system is getting worse. The methodology for the sizing of a driving motor is introduced based on the foundation of determined system configuration and performance target. And the sizing of an engine/generator and a battery is achieved based on simulation results using Dynamic Programming. It is possible to find the optimal sizing of these components by comparing fuel efficiency of hybrid electric propulsion system for 8 driving cycles.

안면 마비와 난청으로 진단된 면역글로불린 G4 연관질환 동반 육아종성 다발 혈관염 1예 (A Case of Granulomatosis with Polyangiitis with IgG4-Related Disease Expressed by Facial Paralysis and Hearing Loss)

  • 김형식;두전강;여승근;김상훈
    • 임상이비인후과
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    • 제29권2호
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    • pp.240-244
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    • 2018
  • Granulomatosis with polyangiitis (GPA) and Immunoglobulin (Ig) $G_4$-related disease ($IgG_4$-RD) are rare diseases and early diagnosis and proper management are imperative to prevent multi-organ damage. The authors present a case of a 60 years old woman who had facial paralysis and hearing loss. Lt intact canal wall tympanomastoidectomy, Lt facial nerve decompression and ossiculoplasty with partial ossicular replacement prosthesis (PORP) was done. During operation, middle ear tissue was biopsied and GPA with $IgG_4$-RD was diagnosed. After methyl prednisolone (MPD) pulse therapy and azathioprine therapy, the severity of paralysis was improved. We present this case because common otologic symptoms like facial palsy and hearing loss could be initial symptoms of rare systemic disease.

외측 심부 비골신경 포착 증후군의 증례 보고 (Rare Disease Entity of Dorsolateral Foot Pain: Lateral Branch of Deep Peroneal Nerve Entrapment Syndrome)

  • 나윤주;여승미;박진호;황지혜
    • Clinical Pain
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    • 제20권2호
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    • pp.122-126
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    • 2021
  • When a patient represents pain in foot, physician can easily overlook compression neuropathy of peripheral nerve as it is uncommon. Among nerve entrapment syndrome encountered in the foot, selective compression in lateral branch of deep peroneal nerve (DPN) is rare. We report a case of a patient with pain and dysesthesia in dorsolateral foot which turned out as lateral branch of deep peroneal nerve entrapment syndrome caused by talonavicular joint effusion. We would like to share diagnostic work up flow and conservative treatment courses. This case manifests the importance of the deep peroneal nerve and its branches in clinical setting of pain and ankle instability.

도공원지의 원료 조성 및 구조에 따른 고평량 도공지의 접힘 터짐 (Fold Cracking of High Grammage Coated Paper Depending on Pulp Composition and Structure of Base Paper)

  • 심규정;윤혜정;오규덕;이학래;여승욱;이용민
    • 펄프종이기술
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    • 제47권4호
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    • pp.38-45
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    • 2015
  • Fold cracking is one of quality troubles of coated papers. In this study, the fold cracking of high grammage ($250g/m^2$) coated paper made with the different pulp composition and layer structure of base paper was investigated. The single layered, high grammage base paper was prepared by mixing of hardwood and softwood bleached kraft pulp fibers with the different ratios. The high grammage coated paper showed the higher fold cracking than low grammage coated paper because of the increase in thickness. The increase in the content of softwood pulp fibers reduced the fold cracking in the case of high grammage coated paper. When the creasing process was conducted before folding process, the fold cracking of coated paper decreased. By manufacturing the base paper with multiply structure, the fold cracking of coated paper could be reduced significantly, especially when the BCTMP and OCC were used as a middle layer and the creasing process was carried out. The delamination of layers in base paper affected the fold cracking positively.

손목굴증후군 환자의 신경생리학적 소견과 혈청 지질 수치와의 상관관계 (Correlation between Serum Lipid Level and Neurophysiological Findings in Patients with Carpal Tunnel Syndrome)

  • 여승현;김동훈;손성연;홍윤희;박재범;주인수
    • Annals of Clinical Neurophysiology
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    • 제12권2호
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    • pp.47-54
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    • 2010
  • Background: Carpal tunnel syndrome (CTS) is the most common entrapment neuropathy caused by compression of the median nerve beneath the transverse carpal ligament. CTS can be correctly diagnosed by the patients' description of symptoms and electrophysiological tests that measure nerve conduction through the wrist. Many previous studies reported various risk factors of CTS, such as obesity, diabetes mellitus, thyroid disease and trauma. Obesity is associated with both hyperlipidemia and CTS. This study focused on the relationship between severity of CTS and serum lipid level. Methods: One hundred fourteen patients with CTS and 74 controls were divided into four groups according to the severity; normal, mild, moderate and severe. And then serum total cholesterol (TC), triglyceride (TG), low-density lipoprotein (LDL-C) and high-density lipoprotein (HDL-C) were measured in each group. Results: There was a positive correlation between TG and CTS severity (p<0.001). But TC, LDL-C and HDL-C were not correlated with CTS severity. Conclusions: These results suggest that high serum TG may act as an aggravating factor of CTS.

리브 보강된 콘크리트 충전 HSS 가새부재의 이력 거동 (Seismic Behavior of Concrete-Filled HSS Bracing Members Reinforced by Rib)

  • 한상환;여승민;김욱태
    • 한국강구조학회 논문집
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    • 제17권1호통권74호
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    • pp.53-62
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    • 2005
  • 본 연구의 목적은 가새 골조에서 사용되는 가새 부재를 보강하여 가새 골조의 이력 거동을 향상시키는 것이다. HSS(Hollow Structural Section) 가새 부재는 국부 좌굴의 발생으로 인하여 인장측 성능에 비해 압축측 성능이 취약한 단점이 있다. 국부 좌굴의 심각성을 감소시키기 위하여 가새 부재에 콘크리트를 충전하는 방법이 사용되었다. Lee and Goel(1987)의 연구 결과에 따르면 콘크리트 충전은 HSS 가새 부재의 국부좌굴의 심각성을 감소시켜 파괴 수명을 증가시켰으나, 가새 부재 중앙부의 국부좌굴을 방지하지 못하여 지속적인 압축 강도의 저감이 나타났다. 따라서 본 연구에서는 가새 부재의 압축 강도를 증가시키고 중앙부의 국부 좌굴을 방지하기 위하여 콘크리트 충전 HSS 가새 부재의 중앙부를 리브로 보강한 실험체를 제작하여 실험하였다. 이를 위하여 리브 보강길이를 변수로 한 총 4개의 실물 크기의 가새 부재를 제작하였다. 하중은 압축과 인장이 대칭인 하중이력을 사용하였다. 본 실험에서 좌굴 모드, 사이클 최대 압축강도와 에너지 소산능력에서 나타난 리브 보강 가새 부재의 성능은 리브 보강길이에 따라 다르게 나타났으며, 63%의 길이로 보강한 실험체가 가장 우수한 성능을 나타내었다.

광촉매 반응에 의한 물 속 시안이온의 처리 (Photocatalytic Treatment of Cyanide in Water)

  • 여승욱;김재현;이호인
    • 대한화학회지
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    • 제46권1호
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    • pp.64-68
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    • 2002
  • 여러 종류의 $TiO_2$를 사용하여 물 속에 녹아있는 시안이온의 광촉매 분해반응에 대한 연구를 수행하였다. 상용 $TiO_2$와 제조한 $TiO_2$의 시안이온 분해활성을 비교해 본 결과, anatase 결정구조를 가진, Aldrich사에서 구입한 상용 $TiO_2$의 활성이 가장 나빴던 것에 비하여 $Ti(OC_3H_7)_4$를 전구체로 사용하여 제조한 $TiO_2$가 가장 우수한 활성을 보였는데, 이는 본 연구에서 사용한 또다른 사용촉매인 Degussa사 $TiO_2$(P25)의 활성을 능가하는 것이었다. 이들 촉매의 반응성 차이는 $TiO_2$표면에 존재하는 산성 수산기와 염기성 수산기 양의 상대적인 비와 같은 촉매의 표면특성에 주로 기인하였다. 가장 우수한 활성을 보인 촉매의 제조 과정에서, 소성대신 환원처리를 하였을 때 더욱 향상된 촉매활성을 보였다.

FPSO 다점 계류 시스템의 최적 설계 연구 (Study on Optimum Design of FPSO Spread Mooring System)

  • 임유창;김경수;정준모;김재우;김진태;여승훈
    • 한국해양공학회지
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    • 제23권6호
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    • pp.61-66
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    • 2009
  • For a spread-moored FPSO (Floating Production, Storage, & Off-loading) subjected to environmental excitation from waves, current, and wind, a procedure to determine optimum length and stiffness of mooring lines is suggested using quasi-static frequency domain response analyses. Coupled relations between design parameters are closely examined. In consideration of this, optimized design parameters are proposed based on minimum weight condition. The initial design parameters for numerical analyses are calculated using the static catenary equation of mooring lines. It is demonstrated the line tension and vessel's offset are influenced by the mooring line length and stiffness. Accordingly it is suggested the optimum vessel's offset range should be determined considering line fatigue damage. The availability and limitation of the application of quasi-static analysis method for spread mooring system are explained by comparing the result of time domain analysis with one of frequency domain analysis.