• The Transactions of the Korean Institute of Electrical Engineers
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• v.41 no.6
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• pp.600-606
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• 1992

The series connection of power switching semiconductor elements is essential when a high voltage converter is made, so researches are being conducted to further develop this technology. In the series connection of power switching semiconductor elements, the main problem is that simultaneous conduction at turn-on and simultaneous blocking at turn-off together with voltage balancing are unattainable because of the difference of their switching characteristics. In this paper a novel series connection algorithm is proposed, which can implement not only the synchronization of the points of turn-on and turn-off time but the dynamic voltage balancing in spite of the difference of each switching characteristics. The proposed method is that the compensated control signal is attained from the voltage feedback signal and applied to the series-connected power transistors independently. Computer simulation and experimental results verify its validity.

• Journal of the Korean Society of Clothing and Textiles
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• v.21 no.3
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• pp.600-606
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• 1997

The dyeing with loess has been studied. Two kinds of cotton fabrics having different thickness and density were dyed in loess paste bath. The color differences of the fabrics which were dyed repeatedly.five times were not significant. The dyeing of cotton fabrics with loess was not exactly reproducible, but dyeability of the cotton fabrics of high density was better than that of low density. Loess on the dye6 fabrics was physically jammed between the fibers in the form of the fine particles. The cotton fabrics dyed with loess have good light fastness, but their laundering fastness and abrasion fastness were not good. An aftertreatment was carried out by using the extracted solution from acorn or persimon, and FeSO4 lot improving fastness. When the dyed fabrics was after-treated with FeSO4, the laundering fastness and wet abrasion fastness were improved extremely.

• International conference on construction engineering and project management
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• 2005.10a
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• pp.606-614
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• 2005

This paper deals with new realizations of research, scientific development, managerial and economic optimizations for prefabricated building systems. In the literature, all scientific fields are worked out based on the efficiencies, costs, benefits, choice of execution design, technical demands, aesthetical point of view, as well as the total economics. In the present example of a school-building for communities in the third world, the following criteria have been regarded: The optimal superstructure of prefabricated concrete building systems; the particularity of countries of the Third World (e.g. the climate, the political and the economic conditions); the time for construction and necessary innovative developments for an economically optimized superstructure. Added to this are alternative construction-methods and costs for a simple but variable system which can be adapted to changing functions, where variability should be the main point. For example, a school building that is to be adapted by varying number of rooms to cater for the growing number of pupils.

• 한국신재생에너지학회:학술대회논문집
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• 2007.06a
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• pp.606-609
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• 2007

An experimental study was carried out to investigate the heat value change by various conditions of wood sawdust gasification in the 1-dimensional downdraft flow fixed bed gasifier. The preheated air and steam were used as a gasifying agent. The components of syngas were influenced increasing residence time of supplied agent. The operating parameters, the supplied agent temperature and steam addition were used. The oxidizer temperature was varied from 500K to 620K. The gasification process was monitored by measuring temperature at three points near the biomass using R-type thermocouples and the syngas composition was analyzed by gas chromatograph. We get the sample gas at the end of gasifier. Finally, the amount of hydrogen and methane were increased widely as increasing the oxidizer temperature and adding steam.

• Proceedings of the IEEK Conference
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• 2008.06a
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• pp.605-606
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• 2008

The distance detection system receives stereo video input through 2 CCD cameras. Using a decoder, the image is changed to the YCbCr4:2:2 format and only the Y signal is saved in the 4*256*8bit shift register of the Dual-Port SRAM. As a result of the matching procedure, the Depth value, which is the distance information, is saved in SRAM, and the Depth Map is made and output to the TFT-LCD screen.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2004.05a
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• pp.601-606
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• 2004

This paper deals with friction-induced vibration of disc brake system under constant friction coefficient. A linear, lumped and distributed parameter model to represent the floating caliper disc brake system is proposed. The complex eigenvalues are used to investigate the dynamic stability and in order to verify simulations which are based on the theoretical model, the experimental modal test and the dynamometer test are performed. The comparison of experimental and theoretical results shows a good agreement and the analysis indicates that mode coupling due to friction force is responsible for disc brake squeal. And squeal type instability is investigated by using the parametric analysis. This indicates parameters which have influence on the propensity of brake squeal. This helped to validate the analysis model and establish confidence in the analysis results. Also they may be useful during system development or diagnostic analysis.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1996.06c
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• pp.598-606
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• 1996

Computer testing system for pumps is an automatic measuring and testing system micro computer. There are two functions to this system. 1. Automatically controlling the testing processes. It includes controlling to testing devices, adjusting test points and starting or stopping the pump. 2. Automatically collecting and calculating the testing data. It includes the collection and calculation of the parameters to be measured, printing the testing reports and plotting the testing curves. When using it the measuring accuracy may be improved and the time for testing may be compressed by use the system . So it is used widely on the world. In this paper the basic construction and the work principle and the testing processes are described.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2003.10a
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• pp.599-606
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• 2003

An analytical model which can simulate the post-cracking nonlinear behavior of reinforced concrete (RC) members such as bars and panels subjected to uniaxial and biaxial tensile stresses is presented. The proposed model includes the description of biaxial failure criteria and the average stress-strain relation of reinforcing steel. Based on strain distribution functions of steel and concrete after cracking, average response of an embedded reinforcement, a criterion to consider the tension-stiffening effect is proposed using the concept of average stresses and strains. The validity of the introduced model is established by comparing the analytical predictions for reinforced concrete tension members with results from experimental studies. Finally, correlation studies between analytical results and experimental data from biaxial tension test are conducted with the objective to establish the validity of the proposed models and identify the significance of various effects on the response of biaxially loaded reinforced concrete panels.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2007.11a
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• pp.606-611
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• 2007

Proper orthogonal decomposition (POD) is a method for extracting bases for modal decomposition from the ensemble of dynamic signals. Using the POD method, we analyzed the proper orthogonal modes (POMs) of AFM microcantilevers in dynamic mode operations such as Tapping Mode. The POMs and POVs (proper orthogonal values) were computed through MATLAB simulation for the 5-mode model of the microcantilever. We found that the POV portion of the higher POMs of the tapping microcanilever slightly increased in comparison with no tapping. This implies that the modal energy in the fundamental mode can be transferred to the higher modes during tapping.

• The Journal of the Korean dental association
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• v.48 no.8
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• pp.594-606
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• 2010

Lymph node status is the single most important prognostic factor in oral cancer because lymph node involvement decreases overall survival by 50%. Appropriate management of the regional lymphatics, therefore, plays a central role in the treatment of the oral cancer patients. The purposes of this article are to present the history of neck dissections, including current neck dissection classification, describe the technique of the most common neck dissection applicable to oral cavity cancers, and discuss some of the complications associated with neck dissection. Finally, a brief review of elective neck dissection and sentinel lymph node biopsy will be presented. It is necessary that dentists have to be interested in oral cancer and these interest will make it possible to prevent oral cancer, detect it earlier and also improve the prognosis, survival and the quality of life of survivors.