• 대한기계학회논문집
• /
• 제13권3호
• /
• pp.490-499
• /
• 1989

본 연구에서의 CO$_{2}$ 프로세스는 1차 루프인 원자로에서 유도되는 나트륨 과 2차 루프인 CO$_{2}$ 가스터빈 사이클로 구성하였고, CO$_{2}$ 임계점 부근에서 압축을 행하였다. 또한 최적의 사이클을 결정하기 위해 h-s 선도와 이에 대한 열역 학적, 칼로리로 유도하였다. 그리고 최적화를 위해 출력을 각각 300,600, 1000MWe로 선택하였고, 터빈 입구압은 150-350bar의 범위로 선택하였으며 이들로부터 열효율에 영향을 주는 각 설계변수의 특성을 연구 분석하였다.

• 한국임상수의학회지
• /
• 제35권2호
• /
• pp.46-49
• /
• 2018

A common kestrel was admitted to Chungnam wild animal rescue center, having been unable to fly. On the physical examination, the bird was presented with contusion and swelling on its right humerus closed fraction and had pain response. Radiographic examination was explicitly revealed closed fracture on right proximal humerus. Its closed fracture was reduced with tie-in fixator and figure-of-eight tension band, and inserted pins on its right humerus surgery were removed on the $14^{th}$ day after the surgery. As Falco tinnunculus was able to move its wings from Day $21^{st}$ day, its rehabilitation was done at outdoor facility and it was successfully released. Proximal humerus reduction with tie-in fixator and the wire was a success, and this treatment with reference to this study will be surely effective to support the other wildbird's reduction stability.

• International Journal of Control, Automation, and Systems
• /
• 제5권1호
• /
• pp.24-34
• /
• 2007

Closed-loop active twist control of integral helicopter rotor blades is investigated in this paper for reducing hub vibration induced in forward flight. A four-bladed fully articulated integral twist-actuated rotor system has been designed and tested successfully in wind tunnel in open-loop actuation. The integral twist deformation of the blades is generated using active fiber composite actuators embedded in the composite blade construction. An analytical framework is developed to examine integrally twisted helicopter blades and their aeroelastic behavior during different flight conditions. This aeroelastic model stems from a three-dimensional electroelastic beam formulation with geometrical-exactness, and is coupled with finite-state dynamic inflow aerodynamics. A system identification methodology that assumes a linear periodic system is adopted to estimate the harmonic transfer function of the rotor system. A vibration minimizing controller is designed based on this result, which implements a classical disturbance rejection algorithm with some modifications. Using the established analytical framework, the closed-loop controller is numerically simulated and the hub vibratory load reduction capability is demonstrated.

• Clinics in Shoulder and Elbow
• /
• 제8권2호
• /
• pp.181-186
• /
• 2005

An anterior dislocation of the elbow without a fracture of the olecranon is an extremely rare injury. This paper reports a 36-year-old male who stumbled and fell on his outstretched hand during a soccer game. The anteroposterior and lateral radiographs indicated a simple anterior dislocation of the elbow, which was reduced using a closed method. The elbow joint was stable in the range of motion, but the sensation of the two ulnar digits was still reduced. MRI was useful for the identification of the pathoanatomy. At the follow-up examination three months after the initial trauma, the hypesthesia has fully recovered and the patient regained the full range of the elbow and forearm motion without pain and instability. After 18 months, the patient had a normal elbow function, and could play various sports. If an anterior elbow dislocation is detected early, a closed reduction with careful pathoanatomical considerations would be successful.

• Wind and Structures
• /
• 제32권4호
• /
• pp.309-319
• /
• 2021

The vortex-drift pattern over a girder surface, actually demonstrating the complex fluid-structure interactions between the structure and surrounding flow, is strongly correlated with the VIVs but has still not been elucidated and may be useful for modeling VIVs. The complex fluid-structure interactions between the structure and surrounding flow are considerably simplified in constructing a vortex model to describe the vortex-drift pattern characterized by the ratio of the vortex-drift velocity to the oncoming flow velocity, considering the aerodynamic work. A spring-suspended sectional model (SSSM) is used to measure the pressure in wind tunnel tests, and the aerodynamic parameters for a typical streamlined closed-box girder are obtained from the spatial distribution of the phase lags between the distributed aerodynamic forces at each pressure point and the vortex-excited forces (VEFs). The results show that the ratio of the vortex-drift velocity to the oncoming flow velocity is inversely proportional to the vibration amplitude in the lock-in region and therefore attributed to the "lock-in" phenomena of the VIVs. Installing spoilers on handrails can destroy the regular vortex-drift pattern along the girder surface and thus suppress vertical VIVs.

• 대한족부족관절학회지
• /
• 제3권1호
• /
• pp.58-61
• /
• 1999

저자들은 족부주상골의 단독 골절 탈구가 발생한 1례를 도수정복과 경피적 K-강선 고정의 방법으로 치료하여 AOFAS Midfoot scale상 95점의 양호한 결과를 얻었기에 이를 보고하는 바이다.

• 한국자동차공학회논문집
• /
• 제16권3호
• /
• pp.111-117
• /
• 2008

The aim of this paper was to investigate the fluid dynamic behavior of the automotive closed type water pump with balance hole in order to evaluate and justify its overall hydraulic performance and, in particular to analyze the effects of the balance hole on the reduction of hydraulic flow force of it. The analysis has been peformed by applying the commercial computational fluid dynamics (CFD) code, Fluent, to the solution of the 3-D turbulent flow fields of automotive closed type water pump. The reliability of the employed analysis was demonstrated by the comparison between numerical result and experimental data. Although, hydraulic head of the closed type water pump with 3mm diameter of balance hole decreased by 1.1%, axial flow force was effectively reduced by 13.3%, comparison of it with no hole at design point.

• Journal of Power Electronics
• /
• 제12권5호
• /
• pp.800-812
• /
• 2012

This paper analyses the mathematical model and control strategies of a Hybrid Active Power Filter with Injection Circuit (IHAPF). The control strategy based on the load harmonic current detection is selected. A novel control method for a IHAPF, which is based on the analyzed control mathematical model, is proposed. It consists of two closed-control loops. The upper closed-control loop consists of a single fuzzy logic controller and the IHAPF model, while the lower closed-control loop is composed of an Adaptive Network based Fuzzy Inference System (ANFIS) controller, a Neural Generalized Predictive (NGP) regulator and the IHAPF model. The purpose of the lower closed-control loop is to improve the performance of the upper closed-control loop. When compared to other control methods, the simulation and experimental results show that the proposed control method has the advantages of a shorter response time, good online control and very effective harmonics reduction.

• 대한두개안면성형외과학회지
• /
• 제13권2호
• /
• pp.104-110
• /
• 2012

Purpose: Who may dare to state that optimal choice of treating nasal bone fracture is closed reduction? Few decades of authors' experience in nasal bone fracture has lead to believe that more active and assertive approach in nasal bone fracture by performing simultaneous lateral osteotomy may be applied in proper indications to acquire more accurate reduction and cosmetically satisfying result. Methods: From May 2008 to October 2009, among 241 nasal bone fracture patients, 20 patients underwent simultaneous lateral osteotomy with nasal bone fracture reduction. Followed by rigid septal correction, nasal cavity is packed to stabilize the fracture segment for safer osteotomy. Through intranasal incision, in selected cases of difficult reduction or for cosmetic purposes, various types of lateral osteotomy was performed corresponding to the fracture anatomy, conditions of the nasal cavity. Postoperative nasal packing was retained for one week and nasal dorsum splint for 3 weeks. Results: Lateral osteotomy was utilized for difficult cases of closed reduction, for correction of wide nose, hump and deviation in 9, 5, 2, and 4 cases, respectively. Patient satisfaction was scaled 90% in satisfaction and moderate in 10% (2 cases), complaining of mild nasal tip deviation. Physicians detected 2 cases of apparent deformity with patient recognition; one patient with mild step deformity at the osteotomy site and the other patient with minimal implant mobility. Conclusion: By accompanying profound understanding of the fracture anatomy, more active and assertive approach in nasal fracture reduction can be coincide with simultaneous lateral osteotomy to reduce the rate of secondary deformity and to obtain more cosmetically satisfying result.

• 방사성폐기물학회지
• /
• 제1권1호
• /
• pp.25-39
• /
• 2003

본 연구에서는 고온의 LiCl-Ll$_2$O 용융염계에서 우라늄 산화물의 금속전환과 Li$_2$O의 전해반응이 동시에 진행되는 통합 반응 메카니즘을 기초로 한 전기화학적 금속전환기술을 제안하였다. 본 실험에서는 전기화학적 환원반응에 의해 생성된 Li 금속이온이 음극에 전착과 동시에 우라늄 산화물과 반응하여 금속전환율 99 % 이상의 우라늄 감속을 생성하는 통합 반응 메카니즘을 확인할 수 있었다. 또한 전기화학적 금속전환기술의 공정 적용성 평가 일환으로 우라늄 산화물의 금속전환성, 반응 메카니즘 규명, Li$_2$O의 closed recycle rate 및 물질전달 특성 등의 기초 데이터를 확보하였다 향후 전기화학적 금속전환기술은 LiCl-Li 용융염계의 금속전환공정의 반응조건 제한성 해소, 금속전환율 향상 및 공정의 단순화 등의 기술성과 경제성 향상 측면에서 획기적인 방안으로 고려될 수 있을 것으로 판단된다.