• Journal of the Korea institute for structural maintenance and inspection
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• v.18 no.1
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• pp.19-30
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• 2014

In this study nonlinear FEM analysis for steel pylon base of a cable supported bridge is performed in order to compare the results of Akashi-Kaikyo bridge's design specification established in 1970. Due to convenience of its application, the Akashi grand bridge's design specification has been applied to the base design of cable stayed bridges. It has been using linear spring in order to model prestressed high tensioned bars between steel pylon bottom plates and the base concrete. However, the results of nonlinear FEM analysis revealed that the Akashi-Kaikyo bridge's design specification has various problems in the analysis of the steel pylon base. And the steel pylon base has various complex members connecting with each other, and it is main member to resist against the wind load or the earthquake load. Therefore, the nonlinear FEM analysis has to be conducted in order to predict the behavior of steel pylon base exactly. Also, the nonlinear FEM analysis is more reasonable for the load and resistant factor design.

• Korean Journal of Applied Biomechanics
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• v.23 no.3
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• pp.209-218
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• 2013

This study was to perform the kinetic analysis of forward $1\frac{1}{2}$ somersault on the platform diving. Six men's diving players of the Korea national reserve athletes participated in this study. The variables were analyzed response time, velocity, center of mass (COM), angle, center of pressure (COP) and ground reaction force (GRF) of motion. For measure and analysis of this study, used to synchronized to 4 camcorder and 1 force plate, used to the Kwon3D XP (Ver. 4.0, Visol, Korea) and Kwon GRF (Ver. 2.0, Visol, Korea) for analyzed of variables. The results were as follows; Time factor were observed in maximum knee flexion depending on the extent of use at phase 1 of take-off to execute the somersault. This enabled the subject to secure the highest possible body position in space at the moment of jumping to execute the somersault and prepare for the entry into the water with more ease. Regarding the displacement of COM, all subjects showed rightward movement in the lateral displacement during technical execution. Changes in forward and downward movements were observed in the horizontal and vertical displacements, respectively. In terms of angular shift, the shoulder joint angle tended to decrease on average, and the elbow joints showed gradually increasing angles. This finding can be explained by the shift of the coordinate points of body segments around the rotational axis in order to execute the half-bending movement that can be implemented by pulling the lower limb segments toward the trunk using the upper limb segments. The hip joint angles gradually decreased; this accelerated the rotational movement by narrowing the distance to the trunk. Movement-specific shifts in the COP occurred in the front of and vertical directions. Regarding the changes in GRF, which is influenced by the strong compressive load exerted by the supporting feet, efficient aerial movements were executed through a vertical jump, with no energy lost to the lateral GRF.

• Journal of Chest Surgery
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• v.13 no.3
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• pp.212-218
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• 1980

A severe crushing injury of the chest produce a very striking syndrome referred to as traumatic asphyxia. This syndrome is characterized by bluish-red discoloration of the skin which is limited to the distribution of the valveless veins of the head and neck. And also if it is characterized by bilateral subconjunctival hemorrhages and neurological manifestations. But these clinical entities faded away progressively in a few weeks. Apporximately 90% of the patients who live for more than a few hours will recover from traumatic asphyxia when it occurs as a single entity. And so, death results from either severe associated injuries of from subsequent infection, rather than from pulmonary or cardiac insufficiency in traumatic asphyxia. We have experienced 4 cases of traumatic asphyxia with severe crushing thoracic injuries at department of the chest surgery, Captial Armed forces General Hospital during about 3 years from April 1977 to Aug. 1980. The 1st 22 year-old male was struct 2$\frac{1}{2}$ ton truck on the road and was transferred to this hospital immediately. He had taken tracheostomy due to severe dyspnea with contusion pneumonia and for removal of a large amount of bronchial secretion. The 2nd case was 23 year-old male who was got buried in a chasm. In this case, the heavy metal post tumbled over him back while at work. The 3rd case was 39 year-old male who leapt out of a window in 5th story while fire broke out in living room by oil stove heating. He had multiple rib fracture with right hemothor x and right colle's fracture and pelvic bone fracture. The last 22 year-old male was run over by a gun carriage. The wheel of this gun carriage passed over his thorax and right chin. He was brought to this hospital by helicopter. when he was first examined at emergency room, he was in semicomatose state and has pneurmomediastinum with multiple rib fracture and severe subcutaneous emphysema. As soon as he arrived, bilateral closed thoracostomy was performed and cardiopulmonary resuscitation was done. In hospital 8th weeks, chest series showed fibrothorax in right side even if chest wall stabilized. All 4 cases had multiple petechiae over their facees and chest and bilateral subconjunctival hemorrhages referred to as traumatic asphyxia. 3 cases except one case who received splenectomy, had been suffered from contusion pneumonia and had been treated with respiratory care. In these 3 cases, they had warning of impending injury before accident, and took a deep breath hold it and braces himself. And also, even if he had not impending fear in remaining one case, he had taken a deep breath and had got valsalva maneuver for pulling off the heavy metal post. Intrathoracic pressure rose suddenly and resulted to traumatic asphyxia in this situation. All these cases were recovered completely without sequelae except one fibrothorax, right.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.13 no.1
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• pp.5-14
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• 2003

Principles of a novel pulse growing method are described. The method realized in the crystal growing on a seed from melts under raw melt feeding provided a more reliable control of the crystallization process when producing large alkali halide crystals. The slow natural convection of the melt in the crucible at a constant melt level is intensified by rotating the crucible, while the crystal rotation favors a more symmetrical distribution of thermal stresses over the crystal cross-section. Optimum rotation parameters for the crucible and crystal have been determined. The spatial position oi the solid/liquid phase interface relatively to the melt surface, heaters and the crucible elements are considered. Basing on that consideration, a novel criterion is stated, that is, the immersion extent of the crystallization front (CF) convex toward the melt. When the crystal grows at a <> CF immersion, the raised CF may tear off from the melt partially or completely due to its weight. This results in avoid formation in the crystal. Experimental data on the radial crystal growth speed are discussed. This speed defines the formation of a gas phase layer at the crystal surface. The layer thickness il a function of time a temperature at specific values of pressure in the furnace and the free melt surface dimensions in the gap between the crystal and crucible wall. Analytical expressions have been derived for the impurity component mass transfer at the steady-state growth stage describing two independent processes, the impurity mass transfer along the <> path and its transit along the <> one. The heater (and thus the melt) temperature variation is inherent in any control system. It has been shown that when random temperature changes occur causing its lowering at a rate exceeding $0.5^{\circ}C/min$, a kind of the CF decoration by foreign impurities or by gas bubbles takes place. Short-term temperature changes at one heater or both result in local (i.e., at the front) redistribution of the preset axial growth speed.

• Korean Journal of Agricultural Science
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• v.41 no.4
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• pp.473-480
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• 2014

Upon setting up a dedicated plastic greenhouse for tomato cultivation developed by the Rural Development Administration on the Gyehwa reclaimed land, this study was aimed at analyzing the problems can be occurred in the installation of plastic greenhouse on reclaimed lands as well as finding out solutions for improvement. A relatively cheaper wooden pile was used in the installation in order to supplement the soft ground conditions. Based on the results of ground investigation of the installation site, both the allowable bearing capacity and pulling resistance of the wooden pile with a diameter of 150 mm and a length of 10 m were computed and came out to be 30.645 kN. It was determined that the values were enough to withstand the maximum compressive force (17.206 kN) and the pullout force (20.435 kN) that are generally applied to the greenhouse footing. There are three problems aroused in the process of greenhouse installation, and the corresponding countermeasures are as follow. First, due to the slightly bent shape of the wooden pile, there were phenomenon such as deviation, torsion, and fracture when driving the pile. This could be prevented by the use of the backhoe (0.2) rotating tongs, which are holding the pile, to drive the pile while pushing to the direction of the driving and fixing it until 5 m below ground and applying a soft vibrating pressure until the first 2 m. Second, there exists a concrete independent footing between the column of the greenhouse and the wooden pile driven to the underground water level. Since it is difficult to accurately drive the pile on this independent footing, the problem of footing baseplate used to fix the column being off the independent footing was occurred. In order to handle with this matter, the diameter of the independent footing was changed from 200 mm to 300 mm. Last, after films were covered in the condition that the reinforcing frame and bracing are not installed, there was a phenomenon of columns being pushed away by the strong wind to the maximum of $11m{\cdot}s^{-1}$. It is encouraged to avoid constructions in winter, and the film covering jobs always to be done after the frame construction is completely over. The height of the independent footing was measured for 9 months after the completion of the greenhouse installation, and it was found to be within the margin of error meaning that there was no subsidence. The extent to the framework distortion and the value of inclinometers as well showed not much alteration. In other words, the wooden pile was designed to have a sufficient bearing capacity.

• Journal of the korean academy of Pediatric Dentistry
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• v.30 no.3
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• pp.341-347
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• 2003

Smith-Magenis syndrome (SMS) is a clinically recognizable multiple congenital anomaly and mental retardation syndrome caused by an interstitial deletion of chromosome 17 p11.2. Physical features include short stature, characteristic facial appearance: flattened mid-face, down-turned mouth, prominent and often rosy cheeks; prominent jaw in older children and adults, chronic ear infections, hearing impairment, eye problems, including: strabismus (an eye which turns in or out) and myopia (nearsightedness), hoarse voice, short fingers and toes, heart defects or murmurs, problems related to the urinary system, scoliosis (curvature of the spine), an unusual gait (walking pattern), and decreased sensitivity to pain. Behavioral and developmental characteristics include speech delay and articulation problems, developmental delay, learning disability, mental retardation, hyperactivity, self-injury, including: head banging; hand biting; picking at skin, sores and nails; pulling off finger- and toenails; inserting foreign objects into ears, nose, or other body orifices, explosive outbursts, prolonged tantrums, destructive and aggressive behavior, excitability, arm hugging or hand squeezing when excited. This report is the case of a Korean 3-year-3-month old male with Smith-Magenis syndrome referred from local clinic for the treatment of dental caries. The patient was treated by physical restraint after prophylatic administration of antibiotic(Amoxacillin 50mg/kg).

• The Journal of the Acoustical Society of Korea
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• v.28 no.2
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• pp.119-126
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• 2009

This paper describes the non-stringed guitar composed of laser strings, frets, sound synthesis algorithm and a processor. The laser strings that can depict stroke and playing arpeggios comprise laser modules and photo diodes. Frets are implemented by voltage divider. The guitar body does not need to implement physically because commuted waveguide synthesis is used. The proposed frets enable; players to represent all of chords by the chord glove as well as guitar solo. Sliding, hammering-on and pulling-off sounds are synthesized by using parameters from the voltage divider. Because the pitch shifting corresponds to the time-varying propagation speed in the digital waveguide model, the proposed model can synthesize vibrato as well. After transformation of signals from the laser strings and frets into parameters for synthesis algorithm, the digital signal processor, TMS320F2812, performs the real-time synthesis algorithm and communicates with the DAC. The demonstration movieclip available via the Internet shows one to play a song, 'Arirang', synthesized by proposed algorithm and interfaces in real-time. Consequently, we can conclude that the proposed synthesis algorithm is efficient in guitar solo and there is no problem to play the non-stringed guitar in real-time.

• Journal of the Korean earth science society
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• v.37 no.4
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• pp.218-229
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• 2016

The bedform stability diagram indicates the shape and size of bedforms that will occur to a given grain size and flow velocity. The diagram has been constructed from experimental data which have been mostly acquired by flume experiments. Generally, the flume experiments have been performed on well sorted sediments with unimodal grain size distribution, in order to understand relationship between grain size and flow velocity. According to the diagram, a ripple structure initiates to be formed from lower flow regime flat bed, as the flow velocity increases on the surface of fine-sand or medium-sand sediments. This study aims to verify that the experimental result of bedform stability diagram will be reproduced in our flume experimental systems, and also to confirm that the result is consistent not only on well-sorted sand sediments but also on poorly-sorted sand sediments with bimodal grain size distribution. The experimental results in this study show that initiation of 2D or 3D ripple structure on poorly-sorted sand sediments requires higher flow velocity and shear stress than those for initiation of the structure on well-sorted sand sediments. In general, carbonate sediments are characterized by poor sorting due to inactive hydraulic sorting and bimodal grain size distribution with allochems and matrices. The results suggest that the carbonate depositional system possibly need a higher flow velocity for initial formation of 2D or 3D bedform structures. The reason might be the fact that pulling off and lifting of a grain in poorly sorted sediments require more energy due to sorting, friction, stabilization, armour effects, and their complex interaction. This preliminary study warrants additional experiments under various conditions and more accurate analysis on the relationship between formation of bedforms and grain size distribution.