• JSTS:Journal of Semiconductor Technology and Science
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• v.2 no.3
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• pp.164-169
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• 2002

This paper mainly discusses the hard breakdown of 2.2-nm-thick $SiO_2$ films. It is shown that the hard breakdown event of a 2.2-nm-thick $SiO_2$ film greatly depends on the applied electric field. It is strongly suggested that the local weak spots created by applying a low initial stress to a 2.2-nm-thick $SiO_2$film resist the onset of hard breakdown. In other words, it is anticipated that the stored electrostatic energy is fast dissipated by trap-assisted tunneling in 2.2-nm-thick $SiO_2$ film. Consequently, it is strongly suggested that 2.2-nm-thick $SiO_2$ films are intrinsically quite robust.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.52 no.8
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• pp.354-358
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• 2003

In this paper, insulations characteristics by temperature changes(＋50～-50[$^{\circ}C$]) of $SF_{6}$ gas in the experimental chamber were studied. From this result, at the low temperature, the breakdown voltage was increased with a drop of temperature and an increase of inner pressure in GIS. In addition the ability of insulation of liquid $SF_{6}$ was higher than that of the highly pressurized $SF_{6}$ gas. That is, with progress of low temperature, the main reason of breakdown was not liquefaction of $SF_{6}$ but rapid decrease of inner pressure. This study will come in greatly handy for the insulation design of GIS in a hard cold region

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.254-255
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• 2007

This paper describes underwater discharge phenomena which are less studied than gas, solid and dielectric liquid. Since discharge phenomena were affected by various factors, we investigated the effect of water resistivity in point-plane gap by impulse voltage. In discharge photograph, it is hard to discover the streamer development in positive polarity at high reisistivity. On the other hand, the streamer originated at the tip of rod and developed toward the plane with increasing voltage. It is found that the breakdown voltage of both polarities in lower resistivity are lower than that of high resistivity. High current flowing in lower resistivity before the breakdown induce more streamer and enhance the probability of breakdown.

• Journal of Animal Environmental Science
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• v.7 no.2
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• pp.63-76
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• 2001

A survey was conducted for dairy farmer to manage efficiently of a milking machine and equipment. Labor hours, operation costs, and milking cares for each dairy farmer to estimate the expected numbers of machine and equipment on the basis of the desired dairy farm scale. Based on the results of this research the following conclusions were made: Those who possessed a herringborn system and a tandem parlour system were relatively small portion 2% and 25% respectively of the whole dairy farmer. To improve dairy farmer\`s life, or to reduce his hard labor hours. it was necessary for most of dairy farmers to possess a herringborn system and a tandem parlour system. However, it was difficult for most of farmers to purchase a herringborn system and a tadem parlour system, because these system were very expensive. Only 20% farmers of the whole farmers repaired their milking system, which needed to be repaired quickly enough so that it might was used everyday. Among the parts of milking system, pulsator was found to have the highest breakdown ratio 59%, and vacuum pump was the breakdown ratio 27%. It took more than 2 hours to be milked twice a cow per one day. It means that milking spend so much time. Therefore, the auto milking system should be supplied to decrease hard labor hour.

• Journal of the Korea Institute of Building Construction
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• v.13 no.4
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• pp.321-332
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• 2013

Costs and expenses are intertwined and incurred throughout an entire construction project, even from the pre-construction phase, and each phase has a different impact on the life cycle cost (LCC). However, the cost breakdown structure (CBS) is different in each phase of a building construction project, which makes it hard to reasonably calculate construction cost. For this reason, the boundary conditions were analyzed in this study based on the life cycle cost break structure (LCCBS). In addition, breakdown factors were analyzed based on the boundary conditions to derive a linkage method. The validity of the linkage method was verified through application to actual construction projects. Through the analysis, it was found that the problem of items being left out was reduced by more than 97.2 percent, and the work was done an average of 6 hours faster compared to the conventional method. It is expected that by applying the new LCC system, LCC will be both reduced and calculated in a more efficient manner.

• Korean Journal of Food Science and Technology
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• v.36 no.4
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• pp.598-603
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• 2004

Physicochemical properties of crystalline-structured buckwheat starches cultivated and harvested in Taiwan, China, Korea, and USA were compared. X-ray diffraction pattern showed that all starches were type A as are most natural starches. Moisture contents of starches were 6.30-9.58%, and crude protein contents of Taiwanese and Chinese buckwheats were higher than those of Korean and American ones, whereas Korean and Chinese buckwheats had higher fat contents. Blue-value of Chinese buckwheat was highest at 0.39 and that of Korean buckwheat was lowest at 0.32. Amylose content of American buckwheat was highest at 27.6 and that of Korean buckwheat was lowest. Highest water-binding capacity was shown in Taiwanese buckwheat and lowest in American one. Higher amylase contents in Chinese and American buckwheats reduced expansion and solubility. Highest values of viscosity measured by RVA, breakdown indicating process stability, and setback closely connected to retrogradation of American buckwheat resulted in relatively hard gel.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2010.10a
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• pp.84-87
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• 2010

We manufacture an antifuse OTP (One-time programmable) cell for analog trimming which will be used in power management ICs. For the antifuse cell using dual program voltage of VPP (=7V) and VNN (=-5V), the thin gate oxide is broken down by applying a voltage higher than the hard break-down voltage to the terminals of the antifuse. The area of the manufactured antifuse OTP cell using $0.18{\mu}m$ BCD process is $48.01{\mu}m^2$ and is about 44.6 percent of that of an eFuse cell. The post-program resistances of the antifuse are good with the values under several kilo ohms when we measure twenty test patterns.

• Journal of Periodontal and Implant Science
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• v.51 no.2
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• pp.100-113
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• 2021

Purpose: Previous studies have solely focused on fresh extraction sockets, whereas in clinical settings, alveolar sockets are commonly associated with chronic inflammation. Because the extent of tissue destruction varies depending on the origin and the severity of inflammation, infected alveolar sockets may display various configurations of their remaining soft and hard tissues following tooth extraction. The aim of this study was to classify infected alveolar sockets and to provide the appropriate treatment approaches. Methods: A proposed classification of extraction sockets with chronic inflammation was developed based upon the morphology of the bone defect and soft tissue at the time of tooth extraction. The prevalence of each type of the suggested classification was determined retrospectively in a cohort of patients who underwent, between 2011 and 2015, immediate bone grafting procedures (ridge preservation/augmentation) after tooth extractions at Seoul National University Dental Hospital. Results: The extraction sockets were classified into 5 types: type I, type II, type III, type IV (A & B), and type V. In this system, the severity of bone and soft tissue breakdown increases from type I to type V, while the reconstruction potential and treatment predictability decrease according to the same sequence of socket types. The retrospective screening of the included extraction sites revealed that most of the sockets assigned to ridge preservation displayed features of type IV (86.87%). Conclusions: The present article classified different types of commonly observed infected sockets based on diverse levels of ridge destruction. Type IV sockets, featuring an advanced breakdown of alveolar bone, appear to be more frequent than the other socket types.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.19 no.2
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• pp.75-80
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• 2013

The physicochemical properties of the hydroxypropylated mung bean, sweet potato and water chestnut starches were studied. The blue value and amylose content of mung bean starch were higher than those of sweet potato and water chestnut. Pasting temperature of hydroxypropylated starches were lower than those of native starch and decreased with increasing contents of propylene oxide. Peak viscosity increased with the increase of degree of hydroxypropylation. With increasing contents of propylene oxide, the clarity and swelling power of all starches were increased and those of mung bean were higher. Mung bean starch produced better hard capsules than sweet potato and water chestnut starch. Hydroxypropylated (>6% propylene oxide) water chestnut starch-based capsules completely dissolved, but hydroxypropylated (>12% propylene oxide) mung bean and sweet potato starch-based capsules were dissolved within 10 min. These results showed that hydroxypropylated starch-based capsules have potentials for pharmaceutical applications as a substitute for gelatin hard capsules.

• Korean Journal of Food Science and Technology
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• v.20 no.6
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• pp.890-894
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• 1988

The baking quality of flours produced from Dark Northern Spring(DNS). Hard Red Winter(HRW) and Australian Standard White(ASW) were examined. To improve the baking quality of HRW and ASW, oxidants such as dehydroascorbic acid(DHA) and potassium bromate$(KBrO_3)$ were added. The protein content of HRW was about 3% higher than that of ASW but the specific volume of the baked gluten extracted from HRW and ASW were nearly same. By addition of DHA 100ppm and $KBrO_3$ 50ppm as oxidants to HRW and ASW, the farinogram's stability was strengthened and departure time, time to breakdown were extended. The specific volume of the bread based on HRW was very small but it was improved significantly by addition of oxidants. According to the quality scoring of bread, the breads based on DNS, HRW and ASW were 93, 72 and 75, respectively. The baking quality of HRW was improved by DHA and $KBrO_3$ but not much in ASW.