• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.6 no.2
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• pp.34-41
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• 1997

The objective of this study is to investigate experimentally the frequency characteristics of the hole tones generated by a circular jet of low speed impinging on a plate with a round hole. The experimental results about the sound spectrum and the time wave of the hole tone are presented and discussed in relation with the hole type, the jet velocity and the distance of the nozzle-to-plate with a round hole. From the sound spectrum and time wave measurements, it is found that the hole tone is generated not only by an interaction of convected vortices with a round hole but also by a series of vortex shedding from jets passing through a hole. The hole tones generated by a feedback mechanism consist of many frequency stages and also have a hysteresis phenomenon like an edge tone. But the hole tones generated by a series of vortex shedding have nothing with the stage characteristics. The frequencies of hole tones are influenced by the jet velocity, the distance of the nozzle-to-plate with a round hole and the hole type.

• Aerospace Engineering and Technology
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• v.3 no.2
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• pp.104-115
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• 2004

In this study, contains Design and Simulation data for Tone filter applied to the KSLV-1 FTS Receiver. Received Signal contains unwanted Noise and Jitter which should be eliminated by any kind of filters. In the design of KSLV-1 FTS Receiver, two different type of filters are used. One is Low-Pass Filter for rejecting high order harmonics and another is Tone Filter for sorting pure original signal in the mixed demodulate Signals. For the purpose of this development, various kinds of filter are studied and simulated for finding adequate type of filter.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.27 no.6
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• pp.693-700
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• 2003

The effect of the configuration of the nozzle and the impinging surface on the characteristics of the hole-tones has been experimentally investigated. It is found that the plate-tone is a special case of hole-tones, where the hole diameter is zero. The jet velocity range for hole-tones is divided into the low velocity region associated with laminar jet and the high velocity region with turbulent jet. The frequency of the tone is that for the shear layer instability at the nozzle exit or that attainable by a cascade of vortex pairing process with increase of the impinging distance. When the distance is longer than one diameter the frequency decreases to the terminal value near the preferred frequency of the column mode instability, in the range 0.23< $St_d$<0.53, where $St_d$ is the Strouhal number defined by $fd/U_J$, f the frequency, d the nozzle diameter, and $U_J$ the exit velocity. While the convection speed of the downstream vortex, in the present study, is almost constant at low-speed laminar jet, it increases with distance at high-speed turbulent jet. As the frequency increases, the convection speed decreases in the low frequency range corresponding to the preferred mode, in agreement with the existing experimental data for a free jet.

• Journal of the Korean Society of Clothing and Textiles
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• v.43 no.5
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• pp.666-681
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• 2019

This study examined color trends per season and differences in color utilization between seasons with a focus on hue and tone, based on men's collections. Collected colors classified as hue and tone were subject to frequency and cross analyses according to the study subject. The study results as follows. The hues most frequently used for men's wear in S/S season were red and purple. The red hue was most frequently used even in F/W season. As for tone, blackish tone was found to be prominent, irrespective of season. The cross analysis revealed a significant difference in the main colors' hue and tone utilization between S/S and F/W seasons. In addition, more diverse tones were found to be used in S/S season than F/W season. The hue and tone trends seen in main colors of men's wear in S/S season were analyzed per year, blackish tone and light grayish tone accounted for the majority among all tones. In terms of men's wear in F/W season, blackish tone was frequently used as the main tone, while other tones were found to have a low usage frequency.

• Speech Sciences
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• v.7 no.2
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• pp.193-208
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• 2000

This paper describes a multi-step method of intonation modeling for corpus-based Korean speech synthesizer. We selected 1833 sentences considering various syntactic structures and built a corresponding speech corpus uttered by a female announcer. We detected the pitch using laryngograph signals and manually marked the prosodic boundaries on recorded speech, and carried out the tagging of part-of-speech and syntactic analysis on the text. The detected pitch was separated into 3 frequency bands of low, mid, high frequency components which correspond to the baseline, the word tone, and the syllable tone. We predicted them using the CART method and the Viterbi search algorithm with a word-tone-dictionary. In the collected spoken sentences, 1500 sentences were trained and 333 sentences were tested. In the layer of word tone modeling, we compared two methods. One is to predict the word tone corresponding to the mid-frequency components directly and the other is to predict it by multiplying the ratio of the word tone to the baseline by the baseline. The former method resulted in a mean error of 12.37 Hz and the latter in one of 12.41 Hz, similar to each other. In the layer of syllable tone modeling, it resulted in a mean error rate less than 8.3% comparing with the mean pitch, 193.56 Hz of the announcer, so its performance was relatively good.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.14 no.2
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• pp.105-110
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• 2004

The objective of this study is to obtain the instability characteristics of the plane jet impinging on circular cylinder associated with the cylinder-tone. It is found that the characteristics depends upon he ratio of the cylinder diameter to the nozzle width, D/h, and the jet velocity. When the ratio is oderate the cylinder-tone is similar to the edge-tone. With increase of the ratio, its characteristics ecomes similar to that of the plate-tone in which only the high-speed tone associated with turbulent et is generated. When D/h 〈1. the frequency range, especially the lower limit of frequency, is ignificantly influenced by the cylinder diameter. At around D/h = 1/2, while low speed tones are nduced with the antisymmetric mode of instability and affected by the vortex shedding from the ylinder, high-speed tones are generated, at first, with the symmetric mode of instability. and then, ith antisymmetric mode, as the jet velocity increases.

• Speech Sciences
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• v.12 no.4
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• pp.113-128
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• 2005

The underlying premise of this study was that L1 production is easily transferred into L2 production. In neutral intonation, there is a consonant-tone correlation in Korean: High tone patterns are correlated with voiceless aspirated and tense consonants and Low-High tone patterns are correlated with lax or other voiced consonants. The purpose of this study was to see whether the correlation in Korean (L1) is transferred into English (L2) production and whether the degree of transfer differs depending on the degree of proficiency. Eight Korean speakers and two American speakers participated in the experiment. F0 contours of words and sentences were collected and analyzed. The results of the present study showed that there is a strong correlation between voicing and tone in L2 utterances. When utterance-initial consonant types were voiceless, the word or the sentence began with the H pattern; otherwise it had the LH pattern. The degree of interference differed depending on the degree of proficiency: less proficient speakers showed a stronger correlation in terms of the magnitude (Hz) and size (ms) of the effects on F0. The results indicate that the consonant-tone correlation in L1 is strongly transferred into L2 production and the correlation transfer can be one of the actual aspects that cause L2 speakers to produce deviant L2 accents and intonation.

• The Research Journal of the Costume Culture
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• v.16 no.2
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• pp.293-304
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• 2008

The objectives of this study were to investigate the images in men's hairstyle by hair color, tone, texture, and perceiver's gender, and to examine the characteristics of hairstyle appropriate to seasons. A quasi-experimental method by questionnaire was used, and the experimental design was $4{\times}3{\times}2{\times}2$(hair color$\times$tone$\times$texture$\times$perceiver's$\times$gender) factorial design. The subjects were 372 men and women in their 20s through 50s. five factors of men's hairstyle image were derived by factor analysis: individuality, dignity, romanticism, refinement, and activity. Black hair was perceived to be high in dignity and activity. Bright tone was perceived to be high in individuality, but low in dignity. Men's wave hair was perceived to be higher in individuality than straight hair, but lower in dignity. Perceiver's gender did not give significant influence on evaluation of all image factors. In brown, neutral tone was perceived to be higher in dignity. romanticism, and activity than dark or bright tone. In black, wave hair was perceived to be more refined than straight hair. Black hair matches with winter the most, and yellow matches with spring the most. In terms of tone, dark tone matches with winter; neutral tone matches with autumn; bright tone matches with summer. The results of this study verified that hair color and texture affect men's image perception, and matching hair colors are associated with seasons.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.22 no.4
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• pp.761-770
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• 1997

Narrowband signals can be treated like a single tone interference at the receiver which demodulates wideband signals spectrum overlaid at the same frequency band. In this paper, the single tone interference is effectively suppressed by the use of a multicarrier DPSK direct-sequence(DS) spread spectrum(SS) with maximal-ratio(MR) combining instead of notch filter, which is hard to implement. A noncoherent DPSK system is considered because it is more realizable and does not require any complicate phase tracking, compared with a single carrier system subject to a constraint system bandwidth, and their performance comparisons are validated through simulation. We also propose a suboptimal-ratio(SR) combining which yields uniform and tight low bound on the performance of the MR combining, and then system parameters re optimized by theoretically evaluating the low bound, since an exact analysis appears intractable.

• Journal of the Korean Society of Costume
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• v.50 no.4
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• pp.53-61
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• 2000

The purpose of this study is to classify the characteristics of color communication tools and the color range applied in the Korean fashion industry. To collect the color sample and related references, a questionnaire was distributed during the time period, December, 1995 to June, 1996. From the responses, 2641 color samples used by 109 domestic brands, from 1993 spring/summer to 1996 spring/summer, were collected and analyzed. The data was measured by L*a*b*, and the H V/C formula found in the Munsell notation was used to calculate the data. To classify the color range served for the fashion industry, the distribution of colors are analyzed by difference of season and fabric. The results of this study are as follows : 1. Dominant colors in the Korean fashion industry are Red, Yellow-red, Yellow, purple-blue and low chromatic range colors. 2. While high value colors, such as pale, light greyish, light, dull, dark and vivid tone colors, are dominant in the spring/summer season, low value colors, such as greyish, dark greyish. and deep tone colors and warm colors such as Red, Yellow-red, are prevalent in the fall/winter season. 3. The number of colors commonly used for color planning is less than 20 colors, and both hue and tone are considered important when making color selections. 4. All brands take consumers' color preferences into consideration for color planning, and most of them also take color trends into account. 5. Hue and tone color characteristics analyzed by types of fabrics show more seasonal influence than the fabric itself.