• 한국전산유체공학회:학술대회논문집
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• 2007.10a
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• pp.134-140
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• 2007

Nonlinear parabolized stability equations for compressible flow in general curvilinear coordinate system are derived to deal with a broad range of transition prediction problems on complex geometry. A highly accurate finite difference PSE code has been developed using an implicit marching procedure. Blasius flow is tested. The results of the present computation show good agreement with DNS data. Nonlinear interaction can make the T-S fundamental wave more unstable and the onset of its amplitude decay is shifted downstream relative to linear case. For nonlinear calculations, rather small difference in initial amplitude can produce large change during nonlinear region. Compressible secondary instability at Mach number 1.6 is also simulated and showed that 1.1% initial amplitude for primary mode is enough to trigger the secondary growth.

• Food Science of Animal Resources
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• v.21 no.3
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• pp.272-277
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• 2001

Electrocardiograms in rats fed diets with boiled eggs for 30 days was investigated. Amplitudes of P,Q and R waves were not significant differences among treatment groups. Amplitude of S wave in rats fed the diet with 95% boiled eggs was significantly tended to be increased compared with other groups(P<0.05). Amplitude of T wave in the rats fed the diet with 0% boiled eggs showed the highest values, and there were significant difference among treatment groups fed diets with 0% boiled eggs, 25% and 95% boiled eggs (P<0.05). Durations of P and PQ(PR) waves were high in the rats fed diets with 25% and 50% boiled eggs (P<0.05). Duration of QRS complex showed low in the rats fed diet 0% boiled eggs but not significant difference among treatment groups. Duration of QT was high in the rats fed diet with 0% boiled eggs(P<0.05). This result is assumed that electrocardiograms in the rats is not changed to intake the boiled eggs.

• Speech Sciences
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• v.11 no.4
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• pp.163-171
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• 2004

The primary goal of the present study was to explore more detailed evidence for the influence of aging and gender effects on the capability of Korean healthy, ears to generate DPOAEs. DPOAEs were examined in series of human subjects, with clinically nonnal hearing, ranging in age from 10 to 65 years. All 60 Koreans were divided into 6 age groups. Each age group included 10 participants, 5 females and 5 males. The gender effects on the difference between the absolute amplitude and noise floor value in DPOAEs did not exist. The difference increased as the frequency increased. The aging effects on the difference between the absolute amplitude and noise floor value in DPOAEs did exist. The difference increased as the frequency increased but orderly age effects could not be found. The principle finding was that, when compared between emissions in young and old ears, DPOAEs accurately tracked the systematic deterioration of high-frequency hearing in aging individuals. Such results support the need to reestablish the criterion for interpretation of DPOAEs in the elderly.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.15 no.9
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• pp.3186-3203
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• 2021

In this paper, a multi-scale local difference directional number (MLDDN) pattern is proposed for pig identification. Firstly, the color images of individual pig are converted into grey images by the most significant bits (MSB) quantization, which makes the grey values have better discrimination. Then, Gabor amplitude and phase responses on different scales are obtained by convoluting the grey images with Gabor masks. Next, by calculating the main difference of local edge directions instead of traditionally edge information, the directional numbers of Gabor amplitude and phase responses are encoded. Finally, the block histograms of the encoded images are concatenated on each scale, and the maximum pooling is adopted on different scales to avoid the high feature dimension. Experimental results on two pigsties show that MLDDN impressively outperforms the other widely used local descriptors.

• Annals of Clinical Neurophysiology
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• v.6 no.2
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• pp.75-79
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• 2004

Backgrounds: Electrodiagnostic tests have been developed to estimate the degree of facial nerve injury during the acute phase. Side-to-side amplitude comparison with the affected side expressed as a percentage of the nonaffected side has been one of the most valuable electrophysiologic methods of assessing facial nerve functioning. This study was designed to know whether there is any difference in the side-to-side comparison of amplitudes and terminal latencies of the compound muscle action potentials (CMAP) of the facial muscles in the patients with Bell's palsy. Methods: Electroneurographic recordings with surface electrodes on the frontalis, orbicularis oculi, nasalis, and orbicularis oris muscles were made within 2 weeks post-onset (mean, day 7) in 39 patients. Results: Of the 39 Bell's palsy patients, 38 patients (97.4%) recovered satisfactorily within 6 months. The amplitude of CMAP in all patients was not reduced to 10% or less of that of the contralateral healthy muscle. The correlation of amplitude change between four facial muscles was relatively strong, but the correlation of latency change was weak. When the electroneurographic values were compared in the four muscle groups, the general linear models procedure did not show any significant difference for CMAP amplitude and latency changes (p=0.62-0.63). Conclusions: This study did not show any significant clinical advantage of electroneurographic recordings in more than one facial muscle at the early stage of Bell's palsy.

• Annals of Clinical Neurophysiology
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• v.7 no.2
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• pp.83-87
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• 2005

Background: The study of the medial antebrachial cutaneous nerve (MABCN) is an underused electrodiagnostic tool. But its use is often crucial for assessing mild lower brachial plexus or MABCN lesions, and sometimes for differentiating an ulnar mononeuropathy from a lower brachial plexopathy. This study was designed to know the difference of amplitude and velocity in a stimulation method (orthodromic vs antidromic), side of an arm and sex according by age. Method: MABCN conduction studies were performed orthodromically and antidromically in 90 subjects (42 women and 48 men, ranging from 22 to 79 years of age). We divided subjects into three groups by age (group 1: 20-39 years, group 2: 40-59 years, group 3: 60-79 years). The mean sensory nerve action potential amplitudes and sensory nerve conduction velocities in each group was compared by stimulation method, side of an arm and sex. Result: The amplitudes and velocities made a significant difference between orthodromic and antidromic method in all age groups. At comparison in amplitude and velocity by side of an arm, only amplitude was significantly higher in right arm than left by any stimulation method. The amplitudes and velocities were of no statistically differences in sex except amplitude checked orthodromically in right arm. Conclusion: This study suggests that there is the differences in conduction study of MABCN by stimulation method and side of an arm.

• Journal of Korean Ophthalmic Optics Society
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• v.17 no.3
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• pp.273-278
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• 2012

Purpose: Average of the maximum accommodation amplitude of myopia in different generation, early 20's and early 40's were compared according to gender, degree of myopia. Methods: Maximum amplitude of accommodation for each 100 patients of early 20's and 40's were measured with push-up method. Maximum amplitude of accommodation expectations based on Hofstetter formula were classified into three groups of under, normal and excess. Results: The average of amplitude of accommodation was 9.77~11.64 D $(10.77{\pm}2.49D)$ in early 20's and 4.67~6.21 D $(5.34{\pm}1.28D)$ in early 40's. In early 20's, minimum expectations of amplitude of accommodation for under, normal and excess groups were 20%, 75%, and 5%, repectively. In early 40's, excess and under groups were 5% and 18%, repectively, but there was no excess group. Conclusions: According to increasing age, amplitude of accommodation of both age groups showed decreased, and no significant difference was found in degree of myopia with gender. Difference between mean of expected accommodation amplitude and maximum of accommodation amplitude was compared, and it was found that maximum of accommodation amplitude of 20's was smaller than mean of expected accommodation. From the result, it was expected that people in early 20's who have more working times might have festinated accommodative insufficiency than 40's.

• Transactions of the Korean Society of Pressure Vessels and Piping
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• v.9 no.1
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• pp.25-30
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• 2013

The periodic inspection of piping and pressure vessels welds in nuclear power plant has to provide reliable result related to weld flaws, such as location, maximum amplitude response, ultrasonic length, height and finally the nature or flaw pattern. The founded flaw in ultrasonic inspection is accepted or rejected based on these data. Specially, the amplitude of flaw response is used as basic parameter for flaw sizing and it may cause some deviation in length sizing result. Currently the ultrasonic inspections in nuclear power plant components are performed by specific inspection procedure which describing inspection technique include inspection system, calibration methodology and flaw characterizing. To perform ultrasonic inspection during in-service inspection, reference gain should be established before starting ultrasonic inspection by the requirement of ASME code. This reference gain used as basic criteria to evaluate flaw sizing. Sometimes, a little difference in establishing reference gain between calibration and field condition can lead to deviation in flaw sizing. Due to this difference, the inspection result may cause flaw sizing error. Therefore, the objective of this study is to compare and evaluate the ultrasonic amplitude difference between air filled and water filled pipe in nuclear power plant. Additionally, the accuracy of flaw sizing is estimated by comparing both conditions.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.21 no.10
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• pp.1350-1362
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• 1997

An experimental study has been performed on vortex pairing under fundamental and subharmonic forcing with controlled initial phase differences through hot-wire measurements and a multi-smoke wire flow visualization. For the range of St$_{D}$ < 0.6, vortex pairing was controlled by means of fundamental and subharmonic forcing with varying initial phase differences. Much larger mixing rate was achieved by two-frequency forcing with a proper phase difference than one frequency forcing. As St$_{D}$ decreased, vortex pairing was limited to a narrow region of the initial phase difference between two disturbances and higher amplitudes of the fundamental and its subharmonic at the nozzle exit were required for more stable pairing. As the amplitude of the subharmonic at the nozzle exit increased for fixed St$_{D}$ and fundamental amplitude, the distribution of the subharmonic mode against the variation of the initial phase difference changed from a sine function form into a cusp-like form. Thus, vortex pairing can be controlled more precisely for the former case. For St$_{D}$ > 0.6, non-pairing advection of vortices due to the improper phase difference was sometimes observed in several fundamental forcing amplitudes when only the fundamental was applied. However, when its subharmonic was added, vortex pairing readily occurred. As the initial amplitude of this subharmonic increased, the position of vortex pairing moved upstream. This was thought to be due to the fact that the variation of the initial phase difference between the fundamental and its subharmonic has less effects on vortex pairing in the region of fundamental-only vortex pairing.pairing.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.22 no.3
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• pp.257-264
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• 2012

Objectives: This study's aims were to evaluate the effects of load center of gravity within an object lifted and feet placements on peak EMG amplitude acting on bilateral low back muscle groups, and to suggest adequate foot strategies with an aim to reducing low back pain incidence while lifting asymmetric load. Methods: The hypotheses that asymmetric load imposes more peak EMG amplitude on low back muscles contralateral to load center of gravity than symmetric load and maximum peak EMG amplitude out of bilateral ones can be relieved by locating one foot close to load center of gravity in front of the other were established based on biomechanics including safety margin model and previous researches. 11 male subjects were required to lift symmetrically a 15.8kg object during 2sec according to each conditions; symmetric load-parallel feet (SP), asymmetric load-parallel feet (AP), asymmetric load-one foot contralateral to load center of gravity in front of the other (AL), and asymmetric load-one foot ipsilateral to load center of gravity in front of the other (AR). Bilateral longissimus, iliocostalis, and multifidus on right and left low back area were selected as target muscles, and asymmetric load had load center of gravity 10cm deviated to the right from the center in the frontal plane. Results: Greater peak EMG amplitude in left muscle group than in right one was observed due to the effect of load center of gravity, and mean peak EMG amplitudes on both sides was not affected by load center of gravity because of EMG balancing effect. However, the difference of peak EMG amplitudes between both sides was significantly affected by it. Maximum peak EMG amplitude out of both sides and the difference of peak EMG amplitude between both sides could be reduced with keeping one foot ipsilateral to load center of gravity in front of the other while lifting asymmetric load. Conclusions: It was likely that asymmetric load lead to the elevated incidence of low back pain in comparison with symmetric load based on maximum peak EMG amplitude occurrence and greater imbalanced peak EMG amplitude between both sides. Changing feet positions according to the location of load center of gravity was suggested as one intervention able to reduce the low back pain incidence.