• Proceedings of the KSME Conference
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• 2008.11b
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• pp.2236-2241
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• 2008

The surface heat flux of nuclear fuel rod is the most important factor which can affect safety of reactor and fuel. If fuel rod surface heat flux exceeds the CHF(${\underline{C}}ritical$ ${\underline{H}}eat$ ${\underline{F}}lux$), fuel can be damaged. In case of double cooled annular fuel, which is under developing, contains two coolant channels. Therefore, a generated heat in the fuel pellet can move to inner or outer channel and heat flow direction is decided by both sides heat resistance which varied by dimension and material property change which caused by temperature and irradiation. The new program(called DUO) was developed. For the calculation of surface heat flux, a both sides convection by inner/outer coolant, s gap temperature jump and conduction in the fuel are modeled. Especially, temperature and time dependent fuel dimension and material property change are considered during the iteration. A sample calculation result shows that the DUO program has sufficient performance for annular fuel thermal hydraulics design.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.51 no.9
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• pp.455-463
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• 2002

Ionic Polymer metal composite(IPMC), one of new actuation materials of EAPs is fabricated by electroless plating of platinum on both sides of the perfluorosulfonic acid film or Nafion film and its electromechanical characteristics are investigated. The IPMC strip bends towards anode under electrical field. As the number of plating cycle increases, the distance between plated platinum electrodes on both sides of Nafion membrane decreases and also the displacement is almost inversely proportional to the number of plating. The displacement of IPMC strip depends on voltage magnitude and applied signal frequency and its maximum deformation is observed at a critical frequency, resonant frequency. Low pressure sandblasting is used for surface treatment of Nafion membrane and at 8 times of plating cycle produced actuator with high displacement performance. For more efficiency of fabricated IPMC, it is useful to add one or two surface developing step which is the second reduction process using hydrazine.

• Journal of Medicine and Life Science
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• v.15 no.1
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• pp.12-15
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• 2018

Digastric and stylohyoid muscles are located in the suprahyoid region. There have been few studies about the general morphology of stylohyoid muscle and its relationship with digastric muscle. During routine educational dissection, unusual insertion of bilateral stylohyoid muscle was found in the cadaver of a 92-year-old Korean male, whose cause of death was 'aspiration pneumonia'. Stylohyoid muscle arose from the styloid process, and inserted onto the intermediate tendon of digastric muscle and the hyoid bone on both sides. Each digastric muscle normally consists of an anterior belly, intermediate tendon and a posterior belly. In this cadaver, there were two anterior bellies on right side while one anterior belly was found on left side. Stylohyoid muscle ran medial to the intermediate tendon of digastric muscle on both sides. The anatomical relationship between stylohyoid and digastric muscles was reviewed based on morphological and embryological point of view.

• Structural Engineering and Mechanics
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• v.71 no.5
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• pp.515-524
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• 2019

The present study deals with the simulation of low velocity impact on prestressed and reinforced concrete (RC) slabs supported with different end conditions. The prestress is pre-applied on the RC slab in an analytical approach for the prestressed slab. RC slabs with dimensions $500{\times}600{\times}60mm$, $500{\times}600{\times}80mm$ and $500{\times}600{\times}120mm$ were used by changing support condition in two different ways; (i) Opposite sides simply supported, (ii) Adjacent sides simply supported with opposite corner propped. Deflection response of these specimens were found for the impact due to three different velocities. The effect of grade of concrete on deflection due to the impact of these slabs were also studied. Deflection result of $500{\times}500{\times}50mm$ slab was calculated numerically and compared the result with the available experimental result in literature. Finite element analyses were performed using commercially available ANSYS 16.2 software. The effectiveness of prestressing on impact resistant capacity of RC slabs are demonstrated by the way of comparing the deflection of RC slabs under similar impact loadings.

• Journal of the Korean Physical Society
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• v.73 no.9
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• pp.1346-1350
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• 2018

An electrode-evaporation technology on both the top and bottom sides of the bare vertical-type single chip separated from the traditional substrate by cooling, was developed for III-nitride vertical-type single chip LEDs with thick GaN epilayer. The post-process of the cooling step was followed by sorting the bare vertical-type single chip LEDs into the holes in a pocket-type shadow mask for deposition of the electrodes at the top and bottom sides of bare vertical-type single chip LEDs without the traditional substrate for electrode evaporation technology for vertical-type single chip LEDs. The variation in size of the hole between the designed shadow mask and the deposited electrodes owing to the use of the designed pocket-type shadow mask is investigated. Furthermore, the electrical and the optical properties of bare vertical-type single chip LEDs deposited with two different shapes of n-type electrodes using the pocket-type shadow mask are investigated to explore the possibility of the e-beam evaporation method.

• Journal of Biomedical Engineering Research
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• v.45 no.2
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• pp.66-74
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• 2024

This study analyzed the occurrence of abnormal muscle coactivations based on the assistance of upper limb weight during reaching task in stroke patients. Nine chronic stroke survivors with hemiplegia performed reaching tasks using a programmable haptic robot. Electromyography (EMG) coactivation levels in the upper limb muscles were analyzed using a linear model describing the activation levels of two muscles when the patient's upper limb weight was assisted at 0%, 25%, and 50%. As the upper limb weight assistance of the haptic robot decreased, the magnitude of the EMG signal in both the deltoid and biceps muscles increased simultaneously on both the paretic and non-paretic sides. However, no difference was found between the paretic and non-paretic sides when comparing the slope of the linear model describing the activation relationship between the deltoid and biceps. The aforementioned results suggest that in some stroke survivors, the deltoids, triceps, and biceps on the paretic side may not be abnormally coupled when supporting the upper limbs against gravity. Furthermore, these results suggest that the combination of haptic robots and EMG analysis might be utilized for evaluating abnormal coactivations in stroke patients.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2001.10a
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• pp.25-28
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• 2001

The problem considered is the buckling of a rectangular orthotropic plate, tapered in thickness in a direction parallel to two sides and compressed in that direction. Curves are presented showing the variation of buckling stress coefficient with the special loads. The type of thickness variation is exponential. While this paper is presented how to design for an efficient orthotropic plate taper from physical consideration.

• Journal of the Korean Data and Information Science Society
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• v.11 no.1
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• pp.73-81
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• 2000

The variance inflation factor can be expressed by the square of the ratio of t-statistics associated with slopes of partial regression and partial residual plots. Disagreement of two sides in the interpretation can be occurred, and we analyze it with some illustrations.

• Journal of the Korean Society of Safety
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• v.8 no.4
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• pp.101-106
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• 1993

The streaming current of insulating oil increases with increasing oil velocity and oil amount, A contact potential difference as an energetic state exits in the polymer thin film, both sides of which are contacted by two different metals having different work functions. Accordingly, the potential difference may be a cause for the short circuited transient current flowing through the external circuit. The polymers are electrificated as the electric field Is supplied, and the currents flow with increasing temperature.

• Proceedings of the KIEE Conference
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• summer
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• pp.1094-1096
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• 2004

This paper deals with driver design for displacement pulsation reduction of disk type LOA. Manufactured disk type LOA consists of iron cored disk as a mover and coil wrapped stator which is located at two sides with respect to mover origin.