• The Transactions of the Korean Institute of Electrical Engineers P
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• v.63 no.2
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• pp.74-80
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• 2014

Generator protection device has to detects an internal fault conditions in generator and abnormal operating conditions must be due to the hazards. Loss of excitation may cause generator itself failure as well as serious operating problem in power system, and then requires an appropriate response of generator protection device. Details modeling of generator control system and analysis of transient states in generator are important for optimal operation in power plants. In addition, the fault simulation data are also used for testing the characteristics of IED. In this paper, the hydro generator control system using PSCAD/EMTDC, visual simulation for power systems, was modeled. The generator control system which is composed of generator, turbine, exciter, governor was implemented. The parameters of generator control system model were obtained from field power plant. Loss of excitation simulations were performed while varying the fixed load. Several signals analysis were also performed so as to analyze transients phenomena.

• Journal of the Korean Society of Costume
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• v.23
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• pp.131-150
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• 1994

Knitwears are originated earlier than textiles in human beings life. And then human beings life. And then human beings have been continuously developing as life patterns of human beings are becoming various and society is rapidly changing. Recently , changing life styles of the consumer emphasize the importance of the high quality , individuality , variety , and activity of knitwears. In this study , university women and housewives livings in Seoul have been surveyed in the cause of analyzing of the consumer's actual conditions. And eight brands of th specialized knit enterprises also have been surveyed, though it is imperfect . The purpose of this study lies in giving a help to the rational clothing habits of consumer and presenting some courses for aiming of korean knit industry. I made use of percentage and $x^2$-test for the analysis of the data and analyzed the contents of the question papers.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.11a
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• pp.117-120
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• 2005

The SONOS devices have been fabricated by the conventional $0.35{\mu}m$ complementary metal-oxide-semiconductor (CMOS) process with NOR array. Two-bit operation using conventional process achieve the high density memory compare with other two-bit memory. Lateral diffusion phenomenon in the two-bit operation cause soft error in the memory. In this study, the programming conditions arc investigated in order to reduce lateral diffusion for two-bit operation of CSL-NOR type SONOS flash cell.

• Clinical and Experimental Pediatrics
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• v.51 no.11
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• pp.1147-1151
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• 2008

Functional urinary incontinence, the absence of any neurologic or structural abnormality as a cause of urinary incontinence in children, is one of the most common clinical problems encountered in pediatric and urologic departments, and it can be socially and emotionally distressing for the affected children. The prevalence rates of functional urinary incontinence in school-aged children are not very high and differ between boys and girls. The underlying mechanisms of functional urinary incontinence are heterogenous and can be associated with the following dysfunctions of both the storage and voiding patterns of the bladder: overactive bladder, dysfunctional voiding, lazy bladder syndrome, HinmanAllen syndrome, giggle incontinence, and vaginal voiding. Treatment methods for urinary incontinence in children should be chosen according to these clinical conditions. Treatment modalities generally consist of the treatment of comorbid conditions such as urinary infection and constipation, behavior therapy to modify learned voiding patterns, and pharmacotherapy primarily with anticholinergics and ${\alpha}$-adrenergic blockers. This review discusses the optimal treatment modalities, including treatment of the underlying voiding disorders, and diagnostic approaches related to functional urinary incontinence in children.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.10a
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• pp.646-649
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• 2002

It can be effect on diagnosis of hydraulic machining system to analyze working conditions with shape characteristics of wear debris in a lubricated machine. But, in order to predict and estimate working conditions, it is need to analyze the shape characteristics of wear debris and to identify. Therefor, if shape characteristics of wear debris is identified by computer image analysis and the neural network, it is possible to find the cause and effect of moving condition. In this study, wear debris in the lubricant oil are extracted by membrane filter, and the quantitative value of shape characteristics of wear debris we calculated by the digital image processing. This morphological informations are studied and identified by the artificial neural network. The purpose of this study is In apply morphological characteristics of wear debris to prediction and estimation of working condition in hydraulic driving systems.

• Korean Journal Plant Pathology
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• v.14 no.6
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• pp.618-621
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• 1998

In pseudoperonospora humuli, the cause of hop downy mildew, environmental and host factors affecting laboratory production of oospore were examined. After 7 days incubation of leaf disk inoculated with sporangia on water, additional incubations were carried out under different conditions of temperature and moisture. Oospore production was also compared between very susceptible (Nugget) and resistant (Fuggle) hop cultivars. Oospores were not produced at 18$^{\circ}C$ regardless of other incubation conditions. Leaf disks failed to produce oospore when incubated on water for up to 18 days at 8$^{\circ}C$. No oospores formed on infection sites without necrosis. However, abundant oospores were produced at necrotized infection sites when inoculated leaf disk incubated on dry filter paper for 5 days at 8$^{\circ}C$. Both susceptible and resistant hop cultivars produced abundant oospores. In the measurement of optimal temperature for oospore production, oospores were produced at 6 to 12$^{\circ}C$ Most abundant oospores were produced at 8$^{\circ}C$. We suggest that proper combination of low temperature, dryness and necrosis may be a critical environmental factors for oospore production of P. humuli.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.40 no.5
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• pp.20-26
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• 2008

Behavior of micro stickies was analyzed using model micro stickies prepared with PVAc emulsion adhesive. Flocculation of micro stickies increased with temperature. Acidic state also induced greater flocculation of micro stickies since they became more unstable under these conditions. Flocculation of micro stickies increased as calcium ion concentration increased. But the presence of calcium carbonates made micro stickies dispersed indicating that calcium carbonates cause two different effects on the behavior of micro stickies. Talc increased flocculation of micro stickies because of its hydrophobic nature. Cationic polymer increased flocculation of micro stickies. Especially cationic starch has far greater effect in flocculating sticky particles by forming bridging flocculations.

• Proceedings of the Korean Geotechical Society Conference
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• 2009.03a
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• pp.1100-1106
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• 2009

A debris flow is known as that flood and landslide of water cause much physical human damages worldwide to complex natural disaster that happen combining and happy event is happening mainly in urgent mountains area in domestic. Because happen about debris flow that happen from each place every year and is drift, mechanism of accumulation definitely make clear and great many damage is not running out. Must grasp actual conditions of priority debris flow to need debris flow prevention countermeasure and lay countermeasure to take away damage by debris flow. Because collecting actual conditions of debris flow that happen by objective investigation methods and accuracy, proposed about investigation calamity investigation method so that can calculate debris flow damage and prepare in subsequentness damage.

• KIEE International Transactions on Power Engineering
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• v.4A no.3
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• pp.152-158
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• 2004

The passive filter is economic and efficient in suppressing harmonics but it may cause resonance problems and its performance is constantly dependent on power system impedance or working conditions of loads. This paper presents the DSP (Digital Signal Processor)-based control system, which automatically controls the passive filter in order to solve these problems. The control system can automatically control the passive filter according to working conditions of loads and measured harmonics, reactive power, power factor and so on. Experimental results in the power system using the 100HP DC motor drive are presented in order to verify the performance of the control system.

• Transactions on Electrical and Electronic Materials
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• v.6 no.3
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• pp.87-90
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• 2005

$SiO_2$ via-hole etching with a high aspect ratio is a key process in fabricating ULSI devices; however, accumulated charge during plasma etching can cause etching stop, micro-loading effects, and charge build-up damage. To alleviate this concern, charge-up damage sensor was fabricated for the ultimate goal of real-time monitoring of accumulated charge. As an effort to reach the ultimate goal, fabricated sensor was used for electrical potential measurements of via holes between two poly-Si electrodes and roughly characterized under various plasma conditions using statistical design of experiment (DOE). The successful identification of potential difference under various plasma conditions not only supports the evidence of potential charge-up damage, but also leads the direction of future study.