• Transactions of the Korean Society of Mechanical Engineers
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• v.13 no.3
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• pp.490-499
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• 1989

These days the closed cycle gas turbine attracts considerable attention due to : (1) The possibility of directly coupling the closed cycle gas turbine with a high temperature gas cooled reactor ; (2) the economical use of dry coolers to reduce the thermal charge of the environment ; and (3) the reduction of pollution and energy consumption, by replacing the domestic hearth by a central heating and power station. In this paper, we selected the optimal cycle from the characteristic of thermodynamic cycle for the optimal design of closed CO$_{2}$ gas turbine cycle usuable in nuclear energy power plant. Also the effects of between the parameters and thermal efficiency were investigated by computer simulation. These results and design data will be added to basics in optimal designing closed CO$_{2}$ cycle gas turbine plant.

• Journal of Veterinary Clinics
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• v.35 no.2
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• pp.46-49
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• 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
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• v.5 no.1
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• pp.24-34
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• 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
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• v.8 no.2
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• pp.181-186
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• 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
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• v.32 no.4
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• pp.309-319
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• 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.

• Journal of Korean Foot and Ankle Society
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• v.3 no.1
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• pp.58-61
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• 1999

Isolated fracture dislocation of the tarsal navicular bone is extremely rare. The mechanism of injury of this fracture dislocation is known as a horizontal or axial load on plantar flexed foot. Closed or open reduction is recommended for displaced navicular fracture. We report one case of isolated fracture dislocation of the tarsal navicular which was treated with closed reduction and percutaneous K-wire fixation.

• Transactions of the Korean Society of Automotive Engineers
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• v.16 no.3
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• pp.111-117
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• 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
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• v.12 no.5
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• pp.800-812
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• 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.

• Archives of Craniofacial Surgery
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• v.13 no.2
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• pp.104-110
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• 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.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.1 no.1
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• pp.25-39
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• 2003

This study proposed a new electrolytic reduction technology that is based on the integration of simultaneous uranium oxide metallization and Li$_2$O electrowinning. In this electrolytic reduction reaction, electrolytically reduced Li deposits on cathode and simultaneously reacts with uranium oxides to produce uranium metal showing more than 99% conversion. For the verification of process feasibility, the experiments to obtain basic data on the metallization of uranium oxide, investigation of reaction mechanism, the characteristics of closed recycle of Li$_2$O and mass transfer were carried out. This evolutionary electrolytic reduction technology would give benefits over the conventional Li-reduction process improving economic viability such as: avoidance of handling of chemically active Li-LiCl molten salt increase of metallization yield, and simplification of process.