• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.22 no.7
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• pp.572-575
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• 2009

In this study, we proposed WLED(White-Light Emitting Diode) driver IC for mobile applications. This IC drove WLED for mobile applications with low input voltage and high efficiency by using boost converter. The device was designed by using boost converter applied current-mode control algorithm and provided PWM(Pulse Width Modulation) & analog dimming. Designed IC consisted of bias block, drive block, control block, protection block. We confirmed this device worked well through a application PCB (Printed Circuit Board) test.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2005.05a
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• pp.303-306
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• 2005

This paper presents the frequency-dependent characteristics of leakage currents flowing through ZnO surge arrester block. The leakage current-voltage (I-V) characteristic curves of the commercial ZnO surge arrester blocks were measured. The resistive leakage current was found to increase with increasing frequency in the low conduction region. The capacitance of ZnO block was independent of the magnitude and frequency of the applied voltage. The power losses of ZnO block increase as the frequency of applied voltage increases, because of the dielectric loss related to the frequency of the test voltage.

• Proceedings of the Korea Concrete Institute Conference
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• 2010.05a
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• pp.141-142
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• 2010

This study is related with assumption of stress block parameter for high-strength concrete. The equivalent stress distribution block of KCI design code isn't matched with the real stress distribution of high strength concrete. In this study, we tried to suggest new type of stress block parameter based on both previous test data and theoretical process.

• Proceedings of the Korea Concrete Institute Conference
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• 2003.05a
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• pp.327-332
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• 2003

The incinerated municipal waste can be classified into two general types of ash; fly ash and bottom ash. The fly ash is appointed as specified waste, because it contains harmful heavy metals, ie Pb , Cd, etc. more than permitted standard index. The purpose of this study is to manufacture the non-sintering artificial aggregates using municipal waste incineration fly-ash and to evaluate their applications as coarse aggregates in concrete interlocking block. The test results of water absorpsion, strengths of the concrete block using artificial aggregates showed that the artificial aggregates could be used in part of 10-20% as coarse aggregate in concrete block.

• Journal of The Korean Society of Agricultural Engineers
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• v.50 no.5
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• pp.29-37
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• 2008

Stress-strain relation and stress block parameters of polymer concrete flexural compression members were experimentally investigated. For these purposes, a series of C-shaped polymer concrete specimens subjected to axial compressive load was tested. Based on the test results, we proposed an equation by which the stress-strain relation of polymer concrete can be predicted. In this model, we took account the slope of descending branch beyond the peak stress point of single curve. The proposed equation was numerically integrated to compute the rectangular stress block parameters. Computed ${\beta}_1$ was greater than the values prescribed in ACI 318 Code for cement concrete, and $\gamma$ was about 0.85 that is similar to the value regulated in the ACI.

• Journal of the Korean Society of Clothing and Textiles
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• v.17 no.4
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• pp.565-576
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• 1993

The Purpose of this study was to develop pattern drafting methods of the hip block and sleeve for female college students of 18 to 26 year-old. The study procedures and results were as follows ; 1. 313 female college students were measured, 17items were analyzed statisitcally. 2. New hip block and sleeve sloper were developed based on the result of the data analysis and fitting tests. 3. The sensory test was applied to evaluate the new hip block and sleeve sloper for female college student by comparing it with Japanese Bunka method sloper. According to statistical analysis of the result of 40items on the questionnaire, all the items showed significant difference($$a{\leq_-}0.01$$) between the two, with the new pattern having higher scores. The new drafting method proved to be better fitted at all 40items, and to be comfortable.

• The Korean Journal of Pain
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• v.8 no.2
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• pp.374-377
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• 1995

Percutaneous neurolysis of upper thoracic sympathetic ganglion was performed by simultaneously injecting 3 ml of pure alcohol into the $T_2$ and $T_3$ levels after testng with same amount of local anesthetics on the same sites. We experienced poor sympatholytic effect or intercostal neuritis and Horner's Syndrome as the result of complication of thoracic sympathetic ganglion block. In Case 1, in spite of the good testing result, neurolytic block effect was poor. In Case 2, intercostal neuritis occurred, but neuralgia subsided within 3 weeks. In Case 3, Horner's Syndrome occurred for 1 day. To increase the success rate of block and decrease the incidence of complications, good radio-opaque dye appearance and good test block effect should be obtained.

• Proceedings of the KSR Conference
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• 2004.10a
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• pp.1449-1454
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• 2004

For the research, we developed the hardware and software of the measurement system for on-line test and evaluation. The software controls the hardware of the measurement data and acts as a interface between users and the system hardware. In this paper, we studied performances of the auxiliary block for high-speed railway vehicle. In order to performance these works, the conversion system was developed. Using this system, we obtained the important results, such as voltage values for the battery charger and auxiliary block. Also, we diagnosed the faults and performed the evaluation for auxiliary block using the measurement system and data.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2019.05a
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• pp.12-13
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• 2019

The bearing capacity of the wall against the eccentric load when the washbasin was attached on the ALC block wall was tested. Test methods are BS EN 14688 and BS 5234-2. Tests in accordance with BS EN 14688 showed that the holding capacity of steel was much stronger and more stable when HA-II (chemical anchor) was used than when the washbasin was fixed using HA-I (plastic anchor). As an experimental result according to the Annex K of BS 5234-2, the bearing capacity of ALC block wall corresponded to the "stage in which the force works(performance grade) 1,500N" for all of the cases where a washbasin is fixed using two types of the wall's dedicated anchors(HA-I and HA-II).

• Proceedings of the Korean Institute of Building Construction Conference
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• 2018.11a
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• pp.118-119
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• 2018

The purpose of this study is to investigate the compressive strength and mixing properties of the lightweight block, which has been manufactured without the pre-wetting process, in the lightweight block using domestic artificial lightweight aggregate. The test results of the specimens produced within 30 minutes after the preparation showed high compressive strength but poor permeability. Therefore, the elapsed time after the manufacture, which is expected to have required compressive strength and permeability, was about 60 minutes in this study.