• Journal of the Optical Society of Korea
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• 제13권2호
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• pp.272-278
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• 2009

Recently, there has been a growing interest in optical imaging of neural activity because the optical neuroimaging has considerable advantages over conventional imaging. Birefringence of the axon has been reported to change during neural activation, but the neurophysiological origin of the change is still unresolved. This study hypothesizes that the birefringence signal is at least partially attributed to the transient cellular volume change associated with nerve excitation. To examine this hypothesis, we investigated how the intensity of cross-polarized light transmitting through the axon would change as the size of the axon changes. For this purpose, a two-dimensional finite-difference time-domain program was developed with the improvement of the total-field/scattered-field method which reduces numerical noise. The results support our hypothesis in that the computed cross-polarized signals exhibit some agreement with previously-reported birefringence signals.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1995년도 추계학술대회 논문집 학회본부
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• pp.182-185
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• 1995

The travelling ultrasonic motor(USM) has good some characteristics over conventional servo motors such as compact size, light weight, silent moton, high torque and high speed response. The USM is driven by 2-phase AC electricity. By adjusting the phase difference of the motor power we control rotation, speed and torque of USM. In this paper, we propose design method using PLSI(programmable Large Scale Integration) of USM controller to adjust the phase difference of the motor power. As compared the previous, the new controller has some advantage that high speed, predictable performance, low power and so on.

• 대한기계학회논문집A
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• 제27권4호
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• pp.585-592
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• 2003

Among various sensitivity evaluation techniques, semi-analytical method(SAM) is quite popular since this method is more advantageous than analytical method(AM) and global finite difference method(FDM). However, SAM reveals severe inaccuracy problem when relatively large rigid body motions are identified fur individual elements. Such errors result from the numerical differentiation of the pseudo load vector calculated by the finite difference scheme. In the present study, an iterative method combined with mode decomposition technique is proposed to compute reliable semi-analytical design sensitivities. The improvement of design sensitivities corresponding to the rigid body mode is evaluated by exact differentiation of the rigid body modes and the error of SAM caused by numerical difference scheme is alleviated by using a Von Neumann series approximation considering the higher order terms for the sensitivity derivatives.

• Journal of Ginseng Research
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• 제6권2호
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• pp.149-153
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• 1982

To investigate the effect of light intensity on the growth of shoots and roots, water and chlorophyll contents in the ginseng leaf were determined at 5%, l0%, 20%, 30% light transmittance rate (LTR) with 1,2 and 4 year-old ginseng plants in the field. Stem length, size of the leaf, water and chlorophyll contents were decreased as the increase of the light intensity in all ages of ginseng plants. The degree of decrease was severe in the one year-old ginseng compared to that of 2, or 4 year-old ginseng, while there was no difference between the 2 and 4 year-old plants. Root weight per plant was highest at 5% LTR in the one year-old plants, while it was at 20% LTR in the 2 and 4 year-old plants. Generally, demand of light for the growth of one year-old ginseng was lower than those of 2 or 4 year-old plants there was no difference of it among the ginseng plants older than 2 years.

• 한국해양공학회지
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• 제18권2호
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• pp.10-17
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• 2004

In this research, a numerical simulation for the acoustic sounds around a two-dimensional circular cylinder in a uniform flaw was developed, using the finite difference lattice Boltzmann model. We examine the boundary condition, which is determined by the distribution function concerning density, velocity, and internal energy at the boundary node. Pressure variation, due to the emission of the acoustic waves, is very small, but we can detect this periodic variation in the region far from the cylinder. Daple-like emission of acoustic waves is seen, and these waves travel with the speed of sound, and are synchronized with the frequency of the lift on the cylinder, due to the Karman vortex street. It is also apparent that the size of the sound pressure is proportional to the central distance to the circular cylinder. The lattice BGK model for compressible fluids is shown to be a powerful tool for the simulation of gas flaws.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2017년도 추계 학술논문 발표대회
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• pp.54-55
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• 2017

The High-rise building has a problem the ventilation performance of natural ventilator by stack effect that it occurs by pressure difference. For that reason the study about natural smoke ventilator of High-rise building consistently needs. Therefore on this study does analysis of difference with abroad through investigate of Natrual smoke ventilator's law, it conducts of natural smoke ventilator's research on the actual condition. As a result on this study, in the case of abroad that it states more specific standards than domestic. Also the result of a field study, it shows that the natural smoke ventilator is installed same size and the number regardless of building's pressure difference.

• Food Science and Biotechnology
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• 제15권4호
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• pp.494-498
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• 2006

An increase in variance (overdispersion) can occur when a binomial statistical analysis is applied to sensory difference test data in which replicate sensory evaluations (tastings) and multiple evaluators (judges) are combined to increase the sample size. Such a practice can cause extensive Type I errors, leading to serious misinterpretations of the data, especially when traditional simple binomial analysis is applied. Alternatively, the use of beta binomial analysis will circumvent the problem of overdispersion. This brief review discusses the uses and computation methodology of beta binomial analysis and in practice evidence for the occurrence of overdispersion.

• 반도체디스플레이기술학회지
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• 제20권2호
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• pp.103-108
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• 2021

The TCD is used as one of the indicators for determining whether TSV Hole is defective. If the TCD is not normal size, it can lead to contamination of the CMP equipment or failure to connect the upper and lower chips. We propose a deep learning model for measuring the TCD. To verify the performance of the proposed model, we compared the prediction results of the proposed model for 2461 via holes with the CD-SEM measurement data and the prediction results of the existing model. Although the number of trainable parameters in the proposed model was about one two-thousandth of the existing model, the results were comparable. The experiment showed that the correlation between CD-SEM and the prediction results of the proposed model measured 98%, the mean absolute difference was 0.051um, the standard deviation of the absolute difference was 0.045um, and the maximum absolute difference was 0.299um on average.

• Journal of Ecology and Environment
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• 제44권3호
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• pp.143-154
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• 2020

Background: Korean wild boars (Sus scrofa coreanus Heude), because of their adaptability, are a widespread large mammal; however, they sometimes cause problems by invading farms and eating the crops, creating insufficiencies of some foods in South Korea. To understand the diet composition of Korean wild boars according to sex and body size, we collected their feces from Mt. Jeombongsan, Seoraksan National Park, South Korea. The sizes of fecal samples were measured, and genomic DNA was extracted from the samples. We amplified specific loci targeting plants (rbcL and trnL) and animals (COI) to detect the food sources of this omnivore and amplified the ZF and SRY regions to determine the sex. Results: In the wild boar feces, Rosaceae and Bryophyte were the most frequently detected plant food sources at the family level and Diptera and Haplotaxida were the most frequently detected animal food sources at the order level. As a result of sex determination, the sex ratio of wild boars collected in the Mt. Jeombongsan area was approximately 1:1. Our result suggested that there is no significant difference between the diet composition of male and female boars. Based on the average cross-sectional area of the feces, the top 25% were classified into the large body size group and the bottom 25% were classified into the small body size group. The large body size group mainly preferred Actinidiaceae, and the small body size group most frequently consumed Fagaceae. The diet of the large body size group was more diverse than the small body size group. Conclusions: Our results showed that the wild boars preferred Rosaceae, especially Sanguisorba and Filipendula, as plant food sources, and Diptera and Coleoptera of Insecta as animal food sources. Based on the results, the dietary preferences of wild boar appear to be distinguished by not their sex but their body size. Our study could help to elucidate the feeding ecology and population structure of wild boar, as well as address conservation and management issues.

• 한국의류산업학회지
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• 제16권1호
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• pp.118-127
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• 2014

This study proposed a revision of standard sizing system for infant clothing to provide exact information for consumers and manufacturers. The size designation was set up by compensating the defect of existing system. Basic body measurement and reference body measurement were analysed according to size designation. The ages of the infants ranged from 0 to 36 month in accordance with safety standard of KC Self-Regularity Safety Confirmation. The results are as follows: Size designation for infant clothing was based on height that was basic body measurement. Chest girth, waist girth, head girth, arm length, foot length and weight were also analysed according to age of the month. It was proposed that height could be written alone and height with age of month did together for size designation. Size intervals of basic and reference body measurements were fixed as follows: size intervals are 5 cm in height, 2 cm in chest girth, 2 cm in waist girth, 1 cm in head girth, 2 cm in arm length, 0.5 cm in foot length and 2 kg in weight. The distributions of height and chest girth showed normal distributions. As height was taller, chest girth was also bigger. But the distribution of waist girth didn't show remarkable change with age of month. The distributions of arm length and weight showed remarkable difference with growth in 0~9 months, but the amount of growth variation got less in 12~18 months.