• Korean Journal of Animal Reproduction
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• v.3 no.1
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• pp.41-47
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• 1979

This experiment was carried out to clarify the methods of the F-body test in human and the B-body test in buil and hog. The effect of pH and albumin concentration on the migration of X- and Y- sperm was also investigated. The results obtained were summarized as follows: 1. In the human semen, the frequency of sperm in which an F-body is visible was different by the fluorochrome. Namely, in case of quinacrine mustard, the F-body frequency was 48.8∼43.4 percent (average 49.6%), and in case of quinacrine dihydrochloride, that was 40.7∼50.8 percent (average 42.0%). 2. The frequency of a, pp.rance of B-body was 43.4${\pm}$1.3 percent in bull semen, and 45.5${\pm}$0.7 percent in hog semen. 3. A, pp.arance of B-body in bovine semen was increased due to duration of time after washing till 12 hours. 4. Separation of X- and Y- spermatozoa using diluents with different hydrogen ion concentration was impossible. 5. A, pp.arance of B-body separated in medium with 6, 10 and 20% ovalbumin was 51.1${\pm}$2.4, 50.6${\pm}$2.5 and 58.2${\pm}$3.0 percent, respectively, and those values were significiantly higher (p<0.01) than corresponding control values.

• Journal of Biosystems Engineering
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• v.17 no.1
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• pp.79-90
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• 1992

Viscoelastic characteristics of agricultural products may be determined through three basic tests ; stress relaxation, creep, and dynamic test. Considering the changeability of living materials, dynamic test in which information is derived in a relatively short time appears to be highly desirable, in which either cyclic stress or cyclic strain is imposed and the remaining quantity (strain or stress) is measured. The periodically varying stress will also result in periodically varying strain which in a viscoelastic material should theoretically be out of phase with the stress, because part of the energy subjected to sample is stored in the material as potential energy and part is dissipated as heat. This behavior results in a complex frequency-dependent compliance denoted by J($i{\omega}$). The complex compliance and therefore the storage compliance, the loss compliance, the phase angle, and percent energy loss for the sample should be obtainable with a given static viscoelastic property of the material under static load. The complex compliance of the rough rice kernel were computed from the Burger's model describing creep behavior of the material which were obtained in the previous study. Also, the effects of cyclic load and moisture content of grain on the dynamic viscoelastic behavior of the samples were analyized. The results obtained from this study were summarized as follows ; 1. The storage compliance of the rough rice kernel slightly decreased with the frequency applied but at above the frequency of 0.1 Hz it was nearly constant with the frequency, and the loss compliance of the sample very rapidly decreased with increase in the frequency on those frequency ranges. 2. It was shown that the storage compliance and the loss compliance of the sample increased with increase in grain moisture content. Effect of grain moisture content on the storage compliance of the sample was highly significant than effect of the frequency applied, but effect of the frequency on the loss compliance of the sample was more significant than effect of grain moisture content. 3. In low moisture content, the percent energy loss of Japonica-type rough rice was much higher than that of Indica-type rough rice, but, in high moisture content, vice versa.

• Progress in Medical Physics
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• v.15 no.3
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• pp.128-133
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• 2004

The fMRI response of the somatosensory cortex was investigated with vibrotactile stimulation. Three different frequencies of 8, 15, or 25 Hz were applied in order to mainly focus on the hemodynamic response of Meissner corpuscles sensitive to frequencies of 5-40 Hz. A closed-system, pneumatically-driven, rubber diaphragm was fabricated that overcame many of the limitations of existing vibrotactile devices and produced robust sensory cortex activation in an fMRI experiment. Increasing frequency vs. activation area was analyzed in terms of signal percent change and number of pixels. Our preliminary results indicated that the distribution of the signal percentage change widened and more activated pixels were obtained with higher frequencies.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.8 no.1
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• pp.12-17
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• 1997

Measuring phonatory stability using MDVP(Multi-dimensional voice program, Kay Elemetrics Corp., NJ, USA) are becoming popular in many Korean clinics and laboratories, yet questions about standardization and reference values have remained. The purpose of present study was to examine the effects of frequency and intensity variation on the results of acoustic analysis related to phonatory stability. Twenty young adults(ten females and ten males) were asked to sustain vowel /a/ for more than 3 seconds under 9 different pitch and loudness conditions. Using MDVP, nine voice samples were analyzed, and jitter percent, fundamental frequency variation, shimmer percent, peak amplitude variation, noise to harmonic ratio, amplitude tremor intensity index, and degree of subharmonics were compared. The results showed that intensity changes can significantly affect various phonatory stability measures, and the lowest perturbation values can be obtained from slightly louder(10dB) phonatory condition than comfortable level phonation.

• Korean Journal of Health Education and Promotion
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• v.9 no.2
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• pp.64-71
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• 1992

The purpose of this study is to investigate the standard weight and the perception of the figure, making girls' high school students the object of scientific study. Furthemore this study will try to find the factor having an effect on the weight through measuring the concern with appearance and health. The study consisted of 658 girls' high school students in Seoul. The data was analyzed by the methods of frequency, percentage, reliability, pearson's correlation coefficient and multiple regression analysis. The results of this study are as follows : 1. The standard size of girls height was 160.95cm, their weight was 52.06kg. 2. 34 percent of the girls tested perceived of themselves of having proper figures. Especially in the case of overweight girls. Only 9.7 percent of girls were satisfied with their figure, the other 83.3 percent were not. 3. 88.4 percent of the girls were concerned with their weight. It was through mass communecation that girls were concerned with wheir weight. 41.2 percent of the girls were concerned with weight much more through mass communication than through any other things. This showed that the effect of mass communication on juveniles was increased. 4. The result of correlation of variable about the concern with appearance(p<0.001), the perception of their figures(p<0.001), the existence of weight controller in friends (p<0.001) and the concern with health(p<0.001) indicated significant positive correlation, on the other hand, the satisfaction of their figures(p<0.001) indicated negative correlation. This showed that the less satisfactory their figures were, the higher their concern about weight was. 5. In order th seize the variable having an effect on the concern with weight, the result of multiple regression analysis was that the concern with appearance (p<0.001), the satisfaction of figure (p<0.001), the concern with health (p<0.05), poket money (p<0.05) and health condition (p<0.05) had a statistically significant effect and the variables also 35.7% out of this model. Concern with appearance had the most important effect of all these variables.

• Advances in nano research
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• v.12 no.1
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• pp.65-72
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• 2022

The dynamic properties (frequencies, mode shapes, damping ratios) of the scaled WPC warehouse are compared using the operational modal analysis approach to the dynamic parameters (frequencies, mode shapes, damping ratios) of the full outer surface of titanium dioxide, 70 micron in thickness. Micro tremor ambient vibration data on ground level was used to provide ambient excitation. For the output-only modal identification, Enhanced Frequency Domain Decomposition (EFDD) was used. This study discovered a strong correlation between mode shapes. Titanium dioxide applied to the entire outer surface of the scaled WPC warehouse results in an average 14.05 percent difference in frequency values and 7.61 percent difference in damping ratios, demonstrating that nanomaterials can be used to increase rigidity in structures, or for reinforcement. Another significant finding in the study was the highest level of adherence of titanium dioxide and similar nanomaterials mentioned in the introduction to WPC structure surfaces.

• Speech Sciences
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• v.13 no.3
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• pp.185-195
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• 2006

This study aims to clarify disfluency loci in a neurogenic stuttering group and to examine how the characteristics are different from a developmental stuttering group. For the study, spoken language samples were collected from 11 adults with developmental stuttering and 11 adults with neurogenic stuttering in the course of speaking tasks including reading, monologue and conversation. Using the collected samples, disfluency characteristics of the two groups were to be investigated by analyzing adaptation effect, consistency effect and frequency of disfluency occurrence according to word position, which are related to the occurrence loci of disfluency. Results of this study were as follows: First, while the neurogenic stuttering group did not show any adaptation effect, the developmental stuttering group showed the adaptation effect that the percent of disfluency word reducing as they read the same materials repeatedly. Second, there was no meaningful difference of consistency effect between the two stuttering groups. Third, the neurogenic stuttering group showed more disfluency frequency in final sounds among the word position compared to the developmental stuttering group.

• Steel and Composite Structures
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• v.32 no.6
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• pp.795-806
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• 2019

In this paper, free vibration of sandwich beam with flexible core resting on orthotropic Pasternak is investigated. The top and bottom layers are reinforced by carbon nanotubes (CNTs). This sandwich structural is modeled by Euler and Frostig theories. The effect of agglomeration using Mori-Tanaka model is considered. The Eringen's theory is applied for size effect. The structural damping is investigated by Kelvin-voigt model. The motion equations are calculated by Hamilton's principle and energy method. Using analytical method, the frequency of the structure is obtained. The effect of agglomeration and CNTs volume percent for different parameter such as damping of structure, thickens and spring constant of elastic medium are presented on the frequency of the composite structure. Results show that with increasing CNTs agglomeration, frequency is decreased.

• Proceedings of the KSME Conference
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• 2004.11a
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• pp.534-538
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• 2004

On this study, we improved diaphgram for micro speaker performance using Taguchi method in discrete design space. The design of diaphgram has an effect on performance of micro speaker such as, thickness of diaphgram, shape of diaphgram, etc. Therefore this study carried to decide shape of diaphgram and thickness of diaphgram for minimizing 2nd natural frequency of diaphgram using Taguchi method. we showed improved design factors that minimized 2nd natural frequency of diaphgram. Also, 2nd natural frequency of diaphgram for micro speaker is reduced up to 37 percent maintaining twist mode shape. From the results of ANOVA, 2nd natural frequency of diaphgram for micro speaker have an effect on position of the outer curved shape and thickness of diaphgram.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.162-165
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• 2004

On this study, we improved diaphgram for micro speaker performance using Taguchi method in discrete design space. The design of diaphgram has an effect on performance of micro speaker such as, thickness of diaphgram, shape of diaphgram, etc. Therefore this study carried to decide shape of diaphgram and thickness of diaphgram for minimizing 2nd natural frequency of diaphgram using Taguchi method. we showed improved design factors that minimized 2nd natural frequency of diaphgram. Also, 2nd natural frequency of diaphgram for micro speaker is reduced up to 37 percent maintaining twist mode shape. From the results of ANOVA, 2nd natural frequency of diaphgram for micro speaker have an effect on position of the outer curved shape and thickness of diaphgram.