• Journal of Korean Neurosurgical Society
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• v.54 no.3
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• pp.265-267
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• 2013

We report a case of bilateral chronic subdural hematoma (CSDH) in a 75-year-old man after exercise using a vibrating belt machine on the head. He suffered from headache and intermittent left side numbness for ten days. He denied any head injuries except eccentric exercise using a vibrating belt on his own head for 20 days. An MRI revealed bilateral CSDH. The hematoma was isodense on the CT scan. We made burr-holes on the both sides under local anesthesia. We identified the neomembrane and dark red subdural fluid on both sides. In the postoperative CT scan, we found an arachnoid cyst on the left temporal pole. Although the arachnoid cyst itself is asymptomatic, trivial injury such as vibrating the head may cause a CSDH.

• Journal of the Korean Society for Precision Engineering
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• v.26 no.7
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• pp.81-90
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• 2009

Due to environmental issues, the development of low energy consumption products has become one of the main topics in the home appliance industry. The energy consumption of a refrigerator depends on the efficiency of its compressor as well as on the refrigerator cycle design, such as the capacity modulation. In this study, a dual capacity, i.e., two-step capacity modulation (TCM), reciprocating compressor is developed. In a TCM compressor, capacity modulation is achieved by changing the dead volume in the cylinder. Instead of a concentric sleeve, an eccentric sleeve, a key, and a spring are used to change the dead volume for the clockwise and counterclockwise rotation of a motor. When the compressor changes its operating mode from full capacity to partial capacity or in opposite direction, the key may collide with the eccentric sleeve. The structural reliability and mode change reliability were confirmed by analysis and experiment.

• Transactions of Materials Processing
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• v.14 no.1 s.73
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• pp.57-64
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• 2005

This study deals with the cold forging process design for shaft in the main part of automobile motors with rectangular deep groove. In forging process, the accuracy and die lift is very important because it have influence on reduction of the production cost and the increase of the production rate. Therefore, it is necessary to develop the manufacturing process of shaft by cold forging., process variables are the cropped face angle of billet and the eccentric load of punch. The former is derived from cropping test, the latter is occurred by clearance between container and preform. Also, grooved preform select the process variable for decrease in punch deflection. We investigate that a deflection of punch and a deformation of preform to every process variables. Through this investigation, we suggest the optimal preform and process design, expect to be improved the tool life in forging process.

• Transactions of the Korean Society of Automotive Engineers
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• v.1 no.1
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• pp.80-89
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• 1993

Performance simulation for a Spark Ignition Wankel rotary Engine is presented in this paper. The volume of chamber at each eccentric shaft angle is evaluated by using geometric models of housing and rotor. A thermodynamic model which includes the first law of thermodynamics, combustion and convective heat transfer from chamber contents to surroundings is imployed. A thermochemical equilibrium model which considers 10 species(CO, $CO_2$, $O_2$, $H_2$, $H_2O$, OH, O, NO, $N_2$) in the burned gas region, is also employed. Four processes of gas exchange, compression, combustion and expansion are considered and the pressure, temperature and composition of chamber gas at each eccentric shaft angle in each process are computed in this performance simulation. This performance simulation must be useful for optimal design of Spark Ignition Wankel Rotray Engine with parametric study for various design parameters and operating conditions.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.05a
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• pp.62-65
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• 2006

This study investigated the behavior of R/C column confined with headed crossties subjected to eccentric loading. The 16 specimens are designed to have adequate confinement steel, determined by ACI seismic design. The variables studied in this research test are eccentricity to depth ratios, spacing of lateral steel and the anchor type of end of crossties. From the test results, all columns showed similar behavior up to the peak load but those columns laterally confined with head presented more ductile behavior after the peak load. The comparisons indicate that the flexural behavior of confined-concrete columns can be computed resonable accurately by P-M interaction curve.

• 유체기계공업학회:학술대회논문집
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• 2006.08a
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• pp.515-516
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• 2006

Internal and inlet flows of a cross-flow fan have been visualized using a particle image velocimetry(PIV) to analyze a relationship with a performance of a room air conditioner(RAC). A test model which has a geometric similarity with the real RAC has been manufactured for the experiment and the flow characteristics have been analyzed with various flow rates and inlet grill angles for the cross-flow fan. The experimental results using the PIV technique have been compared with the existing numerical results. Also, a location and movement of an eccentric vortex which can affect the performance and noise of the RAC has been investigated by the PIV with various flow rates and inlet grill angles.

• Proceedings of the KSME Conference
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• 2000.11b
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• pp.508-513
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• 2000

HANJUNG has developed demonstration plant treating combustion flue gas such as dioxide($SO_2$) and nitrogen oxides(NOx). Before operating this system, we tested the inner airflow characteristic of demonstration plant in the front of plasma reactor field 1 and field 2. The experimental results of $25,000Nm^3/hr$ airflow are compared with the computational results using FLUENT code. It is found that the velocity distribution trends are matched the experimental results with the calculation results. To improve the eccentric airflow in the inlet hood, it is necessary to install the vertical guide vane as well as the horizontal guide vane.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.26 no.12
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• pp.2475-2482
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• 2002

The measurement of residual stresses by the hole-drilling method has been commonly used to evaluate residual stresses in structural members. In this method, eccentricity can usually occur between the hole center and rosette gage center. In this study, the error due to the hole eccentricity is compensated using the neural network. The neural network has trained training examples of normalized eccentricity, eccentric direction and direction of maximum stress at eccentric case using backpropagation learning process. The trained neural network could compensated the error of measured residual stress in experiments with hole eccentricity. The proposed neural network is very useful for compensation of the error due to hole eccentricity in hole-drilling method.

• Proceedings of the KSME Conference
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• 2001.11a
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• pp.412-418
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• 2001

The measurement of residual stresses by the hole-drilling method has been commonly used to evaluate residual stresses in structural members. In this method, eccentricity can usually occur between the hole center and rosette gage center. In this study, the error due to the hole eccentricity is corrected using the neural network. The neural network has trained training examples of normalized eccentricity, eccentric direction and direction of maximum stress at eccentric case using backpropagation learning process. The trained neural network could corrected the error of measured residual stress in experiments with hole eccentricity. The proposed neural network is very useful for correction of the error due to hole eccentricity in hole-drilling method.

• 한국가시화정보학회:학술대회논문집
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• 2004.11a
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• pp.34-35
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• 2004

Three dimensional density distributions of impinging and eccentric flames have been investigated by digital speckle tomography. The flames have been ignited by a mixture of butane and air from a circular nozzle and impinged against a plate located at the upper side of the burner exit. For comparison with experimental data, computer synthesized phantoms of impinging and eccentric flames have been reconstructed by a developed three-dimensional multiplicative algebraic reconstruction technique (MART). The advanced reconstruction in the stagnation flow region involved the sharp change of the flow direction and pressure gradient has been developed using a cross-correlation method and new scanning technique for the speckle displacement.