• Proceedings of the Korean Vacuum Society Conference
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• 2007.08a
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• pp.106-106
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• 2007

• Journal of radiological science and technology
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• v.21 no.2
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• pp.57-63
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• 1998

AEC was designed to assist in the production of radiographs of equal density and to aid in the production f consistently high quality radiographs. Many improvements have been made in the AEC and these have helped to increase it's acceptance. Newer system (Falling load) control kVp and mA as well as exposure time. Authors have had experiments about the characteristics of AEC by Zone System. Zone System is the method to detection of photographic image qualify by control the photo print from Fred Archer and Ansel Adams. With the Zone System theory the experiments of density control, characteristics of phantom thickness and reproducibility of occupation rate of contrast media could make quality control of X-ray photography effectively in falling load system.

• Proceedings of the SAREK Conference
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• 2009.06a
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• pp.254-259
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• 2009

The mixed cooling dryer has been developed significantly by adopting both advantages of cooling dryers and desiccant dryers. In this study, it is introduced that the desired effect, such as drying rate period reduction and energy-saving, could be achieved only by adding the desiccant dryer if an existing cooling dryer is used. The experiment should be conducted for quite long time due to the material selection, so it is regrettable that there are not enough data.

• Journal of Technologic Dentistry
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• v.30 no.2
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• pp.71-77
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• 2008

Acrylic resin has been widely used for dental care since it requires relatively simple equipment for treatment and less time and cost are needed to make it and, furthermore, proper strength, dimensional stability as well as durability are ensured after treatment. A survey of denture users showed, however, that more than 60% of dentures installed need repair each year, $22{\sim}30%$ of which are due to falling out of teeth. This study is aimed at exploring the means to increase bonding strength of denture by reducing the causes for falling out of teeth during the processing of dentures. For this aim, the bonding strength of dentures was compares and analyzed before and after the glazed surface of teeth contacting denture was eliminated. From the analysis, it was revealed that there was a difference of 4.3MPa in average in bonding strength between 20MPa for the glazed surface not eliminated and 24.3MPa for the glazed surface eliminated.

• The Korean Journal of Food And Nutrition
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• v.20 no.2
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• pp.164-172
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• 2007

The purpose of this study was to investigate the properties of yellow layer cake made with bamboo leaf powder. Physical properties of the medium and cake flour with bamboo leaf powder were tested by falling number, farinogram, alveogram and after making yellow layer cake, which were tested by rheometer and water activity etc. We found that falling numbers increased with addition of bamboo leaf powder and adding bamboo leaf powder to the flour decreased peak viscosity, holding strength, final viscosity etc. The p value of the alveogram increased for the flour containing bamboo leaf powder increased, but development time and stability decreased. The water activity of the yellow layer cakes made with bamboo leaf powder decreased during storage, but they did not show significant differences. The results of the sensory test showed that the 3% of addition of bamboo leaf powder had the best scores.

• Journal of the Korean Society of Safety
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• v.11 no.1
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• pp.108-120
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• 1996

It is a problems in industrial accidents that the knowledge for industrial accidents is obtained by experience, not by experiment. This experiential knowledge is obtained by Investigating accident cases and utilizing those for safety education. Therefore, in this paper, the situation about the serious accident of construction is analyzed by occupation, a kind of construction, time group, season, type of accident, and accidental cause. And the mutual · relations of these factors are studied. The most frequent type of the serious accidents of construction Is the falling accident. It happenes most frequently at apartment construction among kinds of construction and to structural worker, finishing worker, normal worker in order among occupations. And it is found that the most critical causes of the falling accident are the imperfection of safety facilities and unwearing of protection equipments, so a number of accidents can be reduced by the expansion of safety facilities and wearing of protection equipments absolutely. The counterplan of prohibition of accidents and the direction of government policy are presented by a series of nalyses for accident cases.

• Proceedings of the KIEE Conference
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• 1994.11a
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• pp.156-158
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• 1994

In recent days, the various adjustable speed drives are widely employed at the industrial applications for the purpose of energy saving and speed control. In particular, for the machine control applications. the switching frequency is required to be increased for better dynamic performance of the drive. Moreover, this also leads to the reduction of the switching loss of the device. For IGBT (Insulated Gate Bipolar Transistor), the most widely used switching device in the inverters below the 100[kW] range, the falling and falling time is of the order about $200{\sim}300[ns]$. Therefore unexpected phenomena occurs such as voltage spikes due to high gradient of current at the switching instant, the weakening of motor insulation due to high gradient of voltage. In this paper, a new voltage gradient suppression technique is presented in both theoretically and experimentally.

• The Journal of Korea Robotics Society
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• v.13 no.4
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• pp.248-255
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• 2018

In this paper, a design for a vehicle body of an armored robot for complex disasters is described. The proposed design considers various requirements in complex disaster situations. Fire, explosion, and poisonous gas may occur simultaneously under those sites. Therefore, the armored robot needs a vehicle body that can protect people from falling objects, high temperature, and poisonous gas. In addition, it should provide intuitive control devices and realistic surrounding views to help the operator respond to emergent situations. To fulfill these requirements of the vehicle body, firstly, the frame was designed to withstand the impact of falling objects. Secondly, the positive pressure device and the cooling device were applied. Thirdly, a panoramic view was implemented that enables real-time observation of surroundings through a number of image sensors. Finally, the cockpit in the vehicle body was designed focused on the manipulability of the armored robot in disaster sites.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.39 no.7
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• pp.97-103
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• 2002

In this paper, a Logarithmic Video Amplifier(LVA) for radar system or satellite communications is described. The proposed LVA is composed of a input stage, amplification stage, and output stage. As well as a novel series-parallel architecture is proposed for the purpose of wide dynamic range and high speed operation, a newly developed input stage is designed in order to control the voltage level between LVA and detector diode. The LVA is fabricated with a 1.5um 2-poly 2-metal n-well Bi-CMOS technology, and the chip area is 1310 um x 1540 um. From the experimental results, it consumes 190 mW at 10V power supply, the chip has 60 dB dynamic range and 100ns falling time.

• Journal of IKEEE
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• v.23 no.2
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• pp.552-556
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• 2019

This paper present a capless low drop out regulator (LDO) that improves the load transient response characteristics by using a current regulator. A voltage regulator circuit is placed between the error amplifier and the pass transistor inside the LDO regulator to improve the current characteristics of the voltage line, The proposed fast transient LDO structure was designed by a 0.18 um process with cadence's virtuoso simulation. according to test results, the proposed circuit has a improved transient characteristics compare with conventional LDO. the simulation results show that the transient of rising increases from 1.954 us to 1.378 us and the transient of falling decreases from 19.48 us to 13.33 us compared with conventional capless LDO. this Result has improved response rate of about 29%, 28%.