• Journal of Korean Society of Industrial and Systems Engineering
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• v.29 no.3
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• pp.111-118
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• 2006

This paper presents design and development of a simulator evaluates the performance of a hierarchical cellular system. The proposed hierarchical cellular simulator, consisting of macro, micro, and pico cells, applies the wrap-around technique to reduce simulation time. The simulator is implemented as object oriented class models by using the C++ language in a PC environment. The resulting application can evaluate the interference, SIR(Signal to Interference Ratio), and capacity of a hierarchical cellular system in various configurations. Moreover, it can be used in other applications such as power control, call admission control, hand over scheme.

• Journal of the Korean Society for Precision Engineering
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• v.22 no.10 s.175
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• pp.107-113
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• 2005

This paper presents a method to reduce errors in registration, which is used in transformation coordinate system of the multiple measuring data. In general, the ICP algorithms and feature-based approaches are used for registration. In order to measure wrap-around object, it is necessary to change the scanning direction or set-up of the object. A fixture is made to reduce registration errors caused by inaccurate center point of tooling balls, providing the more accurate registration method. And, the motorized fixture controls rotation and tilting to get precise the measuring data and registration. The proposed motorized fixture and registration method have advantages in accurate registration and precise measurement, compared with the conventional methods.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2003.05a
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• pp.683-688
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• 2003

Vibration characteristics of a fuel rod to be used in KALIMER(Korean Advanced LIquid MEtal Reactor) have been estimated through 3-dimensional finite element analysis and verified by experiment. The fundamental natural frequencies are found to be 6㎐ in air and 2.5㎐ in water. respectively. It has been found that in-water natural frequencies of the fuel rod are lower than in-air ones due to the added mass effect of the fluid filled inside the outer cylinder and they further decreases as the gap between the fuel rod and the outer cylinder increases, namely the added mass effect increases as the gap increases(maximum 54%). It has been also shown that the mass of the wire wrap axially coiled around the fuel rod do not affect the natural frequencies.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2004.04a
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• pp.83-86
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• 2004

The aeroelastic stability analysis of composite bearingless rotors is investigated using a large deflection beam theory in hover. The bearingless rotor configuration consists of a single flexbeam with a wrap-around type torque tube and the pitch links located at the leading edge and trailing edge of the torque tube root. For the analysis of composite bearingless rotors, flexbeam is assumed to be a rectangular section made of laminate. Two-dimensional quasi-steady strip theory and Loewy's aerodynamic theory with the lift deficiency function are used for unsteady aerodynamic computation. The finite element equations of motion for beams are obtained using Hamilton's principle. Numerical results of selected bearingless rotor configurations are obtained for the lay-up of laminae in the flexbeam and pitch links location.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.3
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• pp.566-571
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• 1999

Effects of storage temperature at 18oC and 5oC for 9 days and heating conditions on textural char acteristics in strong wheat flour gels were investigated using a Instron after microwave (2450MHz, 700W). Heating condition did not affect the texture property in the wheat flour gels, but the frozen storage was very effective to prevent the hardening of the samples. Hardness, adhesiveness, and gumminess in the wheat flour gels decreased in increasing moisture content from 45% to 55%, but there was little change in cohesiveness. The storage at room temperature for 2 hours resulted in increased hardness in the heated wheat flour gels. PE wrap package of the wheat flour gels prevented weight loss by 3~6% and hardening effectively. Sugar, or sugar and shotening resulted in increased hardness in loaf bread. The hardness and weight loss in loaf breads were markedly changed by the heating time with microwave. The most critical time point was around 4 minutes following the heating.

• Journal of the Korea Institute of Military Science and Technology
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• v.18 no.4
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• pp.415-422
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• 2015

The flow field structures of dual jet-in-cross-flow were examined experimentally for in-lined perforated damage holes configuration using particle image velocimetry. Ensemble averaged in-plane velocity and vorticity data in the jet were determined to study the mean jet structure. Jets are formed by pressure differences between upper and lower airfoil surface. The flow structure of vicinity of the thru holes consist of a vortical structure that wrap around the jets like a horseshoe and develop further downstream through a pair of stream-wise vortices. The shape, size and location of the horseshoe vortex were found to be dependent on the angle of attack. In spite of the existence of battle damage holes, the effect on the control force was insignificant when the damage size was not large enough.

• Journal of Auto-vehicle Safety Association
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• v.6 no.1
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• pp.16-21
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• 2014

Recently Korea and many countries are legislated for pedestrian protection as following the GTR(Global Technical Regulation). Most NCAP organization have been applying pedestrian protection results in their own rating system in individual or overall rating. Euro NCAP agency has been introduced it first. From the beginning, Euro NCAP had assessed occupant and pedestrian protection. It has become to strengthen a pedestrian protection protocol every time published. Korea NCAP also has been rating pedestrian protection with overall rating system. This paper proposed to study new pedestrian protection protocol especially upper leg in order to find injury response based on physical test. On Euro NCAP, the upper leg injury are assessed two kind of value which are bending moment and force.

• Archives of Reconstructive Microsurgery
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• v.10 no.2
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• pp.143-148
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• 2001

The hand with amputation of all fingers is useless for activities of daily living and traumatic amputation of some of the fingers can result in the diminished ability to perform power grip and precision grip which is vital to maintain normal function of the hand. Precision grip is used to hold an object between the opposable thumb and flexed fingers. In power grip the object is held between the flexed fingers and the palm while the thumb applies the necessary counterpressure to maintain the grip on the object. A 35 year old male lost his right all fingers including thumb at the level of proximal phalanx from the pressure machinary accident. Thumb was reconstructed using wrap around flap and the second and third fingers were reconstructed using the second and third toe transplantation. Seven years after reconstruction, he uses the reconstructed thumb and the second and the third fingers for eating meals, writing down a paper with a pencil and putting on socks.

• Journal of Broadcast Engineering
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• v.25 no.3
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• pp.313-324
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• 2020

In this paper, we propose a motion vector prediction method that increases the coding efficiency at the boundary of an image by utilizing the 360 video characteristic. In the current VVC method, the location of a neighbor block is excluded from the candidate list for inter prediction in case that it is out of boundary. This can reduce coding efficiency as well as subject quality. To solve this problem, we construct new candidates adding the location of the neighbor block at the boundary of the picture from already decoded information based on the projection method for 360 video coding. To evaluate the performance of the proposed method, we compare with VTM6.0 and 360Lib9.1 under Random Access condition of JVET-360 CTC. As a result, the coding performance shows a BD-rate reduction of 0.02% on average in luma component and 0.05%, 0.06% on average in chroma components respectively, without additional computational complexity. The coding performance at the picture boundary shows a BD-rate reduction of 0.29% on average in luma component and 0.45%, 0.43% on average in chroma components, respectively. Furthermore, we perform subjective quality test with the DSCQS method and obtain MOS values. The MOS value is improved by 0.03 value, and we calculate BD-MOS using MOS value and bit-rate. As a result, the proposed method improved performance by up to 8.78% and 5.18% on average.

• Journal of Photoscience
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• v.9 no.2
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• pp.284-286
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• 2002

The inverted retina of the Onchidium dorsal eye (DE) is composed only of ciliary-type photoreceptor cells (CC's). The outer segment (OS) of the CC is a concentric lamellar structure consisting of many modified ciliary membranes and stains positively with anti-$\beta$-tubulin antibody. Near the base of the OS there are about 30 basal bodies each connecting individually to a cilium. The cilia are rod-shaped at the base, progressing upwards to a flattened sheet-like shape with increasing surface area. Three-dimensional analysis on serial sections demonstrates the ladle-shape of a modified cilium. Many modified cilia wrap around each other like the leaves of a cabbage. Nine pairs of microtubules (MT's) are located regularly in a ring at the base of the cilium, gradually losing their regular arrangement towards the periphery, where they separate into two subgroups that are contained within two swollen portions of a modified cilium. Within the CC of the Onchidium DE, MT's in the modified cilium exist as two poles extending longitudinally in a thin expanded ciliary membrane. This arrangement may support the photoreceptive OS and serve to maintain its structural integrity.