• 한국음향학회:학술대회논문집
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• 한국음향학회 2004년도 춘계학술발표대회 논문집 제23권 1호
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• pp.175-178
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• 2004

선박의 수중방사소음은 다양한 기계류나 추진기 혹은 선체와 유체간의 상호 작용으로 인하여 여러 형태의 특성신호로 나타나게 된다. 이는 선박의 운용조건, 장비 회전특성 및 내부구조에 따라 스펙트럼상에 상이한 주파수로 확인됨은 물론, 신호의 출현 형태에도 다양성을 보이고 있다. 일반적으로 선박소음은 속력 종속적인 추진 계통 성분과 비종속적인 보기류 신호로 구분되나 다수의 신호성분이 혼재되어 발생기원을 분류하는 것은 복잡한 과정을 거쳐야 한다. 본 연구에서는 이러한 점을 해결하기 위해 선박의 Tonal성 신호를 자동으로 탐지하고 분류하기 위해 규준화된 스펙트로그램 상에서 연속되는 신호에 가중치를 주어 지속성 신호여부를 판별한 후에 정해진 임계치를 초과하는 성분을 Tonal로 선정하였다. 선정된 Tonal에 대해 주파수선의 대역특성 및 시간 변동성에 대한 패턴인식 방법을 적용하여 Tonal의 발생기원이 속력 종속/비종속적인지를 자동으로 판별하는 알고리즘의 유용성에 대한 결과를 기술하였다.

• 한국음향학회:학술대회논문집
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• 한국음향학회 2004년도 추계학술발표대회논문집 제23권 2호
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• pp.491-492
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• 2004

선박의 수중방사소음은 다양한 기계류나 추진기 흑은 선체와 유체간의 상호 작용으로 인하여 여러 형태의 특성신호로 나타나며, 속력 종속적인 추진계통 신호 성분과 비종속적인 보기류 신호 성분이 혼재되어 다수의 신호성분으로 나타난다. 또한 토널 신호의 세기와 바다의 음향 전달 특성 등으로 인하여 신호가 미약하게 되거나 끊어져서 불연속하게 나타나기도 한다. 본 연구에서는 이러한 점을 해결하기 위해 선박의 Tonal성 신호를 자동으로 탐지하고 분류하기 위해 스펙트로그램 상에서 연속되는 신호에 가중치를 주어 지속성 신호여부를 판별한 후에 정해진 임계치를 초과하는 성분을 Tonal로 선정하였으며, 선정된 Tonal 신호의 발생 기원이 속력 종속/비종속적인지를 자동으로 판별하는 알고리즘을 실제 선박 방사소음에 대해 적용한 결과에 대해 보고한다.

• 말소리와 음성과학
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• 제10권4호
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• pp.91-99
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• 2018

Korean stops are currently undergoing a tonogenetic sound change, as found in the Seoul dialect in which a merged VOT of aspirated and lax stops induces F0 to be the primary cue for distinguishing the two stops and the lax stops have lower F0 than the aspirated stops. In tonal languages, low tone is produced with a breathy voice. This study investigated whether there are changes in voice quality with respect to the tonogenetic sound change of Korean stops. Two age groups speaking the Seoul dialect participated in this study: five females and six males born in the 1940s and 1950s and nine females and eight males born in the 1980s and 1990s. This study replicated previous findings of VOT and F0 and further examined H1-H2, H1-A1, and H1-A2 to see how they correlate with the sound change. In the older and younger generations, H1-H2, H1-A1, and H1-A2 were significantly lower after the tense stops than after the aspirated and lax stops, but they were not significantly different after the aspirated and lax stops. However, the younger females exhibited some different results for H1-H2 and H1-A2 than the older generation. In the younger females, the H1-H2 mean was higher after the aspirated stops than it was after the lax stops at the vowel onset, and the H1-H2 difference increased at the vowel midpoint. Although there was an inter-speaker variation in the results of H1-H2 and H1-A1, analyses of individual speakers showed that the H1-H2 and H1-A1 were higher after the lax stops than after the aspirated stops in the younger female speakers. These results indicate that lax stops tend to be breathier than aspirated stops in the younger female speakers. They also indicate that changes in voice quality are on Korean stops with tonal sound change, but are still developing.

• 한국도로학회논문집
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• 제15권6호
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• pp.41-47
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• 2013

PURPOSES : The purpose of this study is about noise which is generated from roads and is consist of irregular frequency variation from low frequency to various band. The existing methods of noise reduction are sound barrier that uses insulation material and absorbing material or have applied passive technology of noise reduction by devices. The total frequency band is needed to apply active noise control. METHODS : In this study applies to the field of road traffic environment, signal processing controller and various analog signal input/output, the amplifier module is based on parallel-core embedded processor designed. DSP performs the control algorithm of the road traffic noise. Noise sources in the open space performance of evaluation were applied. In this study, controller of active signal processor was designed based on the module of audio input/output and main controller of embedded process. The controller of active signal processor operates noise reduction algorithm and performance tests of noise reduction in inside and outside environment were executed. RESULTS : The signal processing controller with OMAP-L137 parallel-core processors as the center, DSP processors in the active control operations dealt with quickly. To maximize the operation speed of an object and ARM processor is external function keys and display for functions and evaluating the performance management system was designed for the purpose of the interface. Therefore the reduction of road traffic noise has established an electronic controller-based noise reduction. CONCLUSIONS : It is shown that noise reduction is effective in the case of pour tonal sound and complex tonal sound below 500Hz by appling to Fx-LMS.

• 한국콘텐츠학회논문지
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• 제18권12호
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• pp.372-382
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• 2018

본 연구는 고든의 음악 학습 이론을 스즈키 바이올린 교육에 통합하여 어린이들을 위한 바이올린 교수 학습모델을 만드는 것에 그 목적을 두고 있다. 스즈키 교육에 음악 학습 이론의 원리를 적용하는 주된 목적을 학생들의 오디에이션 개발에 두고 있으며, 스즈키 바이올린 교육과 고든의 음악 학습 이론 원리와의 관련성을 토대로, 스즈키 철학과 커리큘럼의 틀 안에서 오디에이션을 어떻게 가르칠 수 있는지 수업예시로 보여 줄 수 있도록 하였다. 이번 연구는 음악 학습 이론을 적용 할 수 있는 방법들 중 한 가지 가능성만을 제시하고 있으며, 스즈키 바이올린 교육에 음악 학습 이론을 체계적으로 적용하기 위해서는 제시된 수업 계획의 효과와 강점에 대한 추가 연구가 필요하며 스즈키 레퍼토리에서 사용 된 조성 및 리듬 패턴에 대한 보다 완벽한 안내서가 필요하다. 악기를 연주하는 학생들의 오디에이션 능력이 함양된다면, 기계적인 움직임이 아닌, 그들이 듣고, 연주하고, 작곡하는 음악에 대한 이해를 더 깊이 할 수 있을 것으로 기대된다.

• 한국음향학회지
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• 제38권1호
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• pp.128-138
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• 2019

본 논문은 서로 다른 두 개의 LOFAR (LOw Frequency Analysis and Recording)그램을 융합하는 방법을 다룬다. 기존의 방법은 주파수 스펙트럼을 이용하여 LOFAR 그램을 융합하기 때문에, 시간-주파수의 2차원 정보인 토널 신호를 융합하는데 제한적인 성능을 갖는다. 제안하는 방법은 전처리 과정에서 2차원 방향성 양방향 필터링을 이용하며, 전처리된 LOFAR 그램의 국부 비등방성 비교를 기반으로 두 LOFAR 그램을 융합한다. 전처리 과정에서 잡음을 억제하고 토널을 부각시키고 나면 국부 비등방성은 토널과 잡음을 구분하기 위한 척도로 사용될 수 있다. 모의 데이터와 해상 데이터를 이용해 LOFAR 그램 융합 실험을 수행한 결과, 제안한 방법은 기존 기법에 비해 융합된 LOFAR 그램의 잡음레벨을 대등하게 하거나 감소시키는 결과를 낳으며, 융합시 토널 누락 현상을 감소시키는 것을 확인하였다.

• 패션비즈니스
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• 제2권1호
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• pp.12-24
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• 1998

The purpose of this study is to investigate the efficiency of systematic color combination for apparel and textile design. We planned the new color systems, HUE AND TONE COLOR SYSTEM 277 and HUE AND TONE COLOR SYSTEM 253 USED KOREAN TRADITIONAL COLORS. In order to emprove the efficiency, this study aims to explore the development of systematic color combination by computer graphics. With this purpose, this study progressed in the following order and we obtained these results. 1. First, we considered the possibility of the development of the systematic color combination used the new color system, HUE AND TONE COLOR SYSTEM 277. We considered the possibility of the development of the systematic color combination by graphic computer SDS-480. Through the experimental regulation of the RGB (Red, Green, Blue) and HLS (Hue, Lightness, Saturation) we obtained an approximation of the colors of the HUE AND TONE COLOR SYSTEM 277 on the CRT display of SDS-480. 2. We planned the new color system, HUE AND TONE COLOR SYSTEM 253 USED KOREAN TRADITIONAL COLORS for systematic color combination. 3. In a practical application, we tried five principal types of color combination in apparel and textile design, monochromatic combination, tone on tone combination, moderate combination, tonal combination, and contrast combination. 4. Furthermore, we applied the systematic color combination for the textile patterns by tone on tone combination. By using the systematic color combination for apparel and textile design, we realized the efficiency and utility of the systematic color combination.

• 유체기계공업학회:학술대회논문집
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• 유체기계공업학회 2002년도 유체기계 연구개발 발표회 논문집
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• pp.123-128
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• 2002

Over the range(OTR) has been applied for cooking and ventilation functions especially in northern Amarica. Because flow rate and operating rpm of the double sided sirocco fan for ventilation are much higher and than the microwave oven system, the major noise source is the sirocco fm. Recently, the quiet fan development is one of very important issues for amenity. In this study, the noise source identification using multi-microphone array system was carefully carried out and numerical simulations for understanding the aerodynamic and aeroacoustic of the fan were peformed. The sound level of tonal noise is predicted with a good accuracy but that of the broadband shows some discrepancy. In order to reduce the broadband noise, the inlet region of sirocco fan have to be modified that the secondary flow should be suppressed. Based on these results, new low noise fan and OTR is now developing.

• International Journal of Aeronautical and Space Sciences
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• 제18권1호
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• pp.144-153
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• 2017

In recent years, unmanned aerial vehicles (UAVs) have been developed and studied for various applications, including drone deliveries, broadcasting, scouting, crop dusting, and firefighting. To enable the wide use of UAVs, their exact aeroacoustic characteristics must be assessed. In this study, a noise prediction method for a ducted fan UAV with complicated geometry was developed. In general, calculation efficiency is increased by simulating a ducted fan UAV without the struts that fix the fuselage to the ducts. However, numerical predictions of noise and aerodynamics differ according to whether struts are present. In terms of aerodynamic performance, the total thrust with and without struts is similar owing to the tendency of the thrust of a blade to offset the drag of the struts. However, in aeroacoustic simulations, the strut effect should be considered in order to predict the UAV's noise because noise from the blades can be changed by the strut effect. Modelling of the strut effect revealed that the dominant tonal noises were closely correlated with the blade passage frequency of the experimental results. Based on the successful detection of noise sources from a ducted fan UAV system, using the proposed noise contribution contour, methods for noise reduction can be suggested by comparing numerical results with measured noise profiles.

• 대한음성학회:학술대회논문집
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• 대한음성학회 2007년도 한국음성과학회 공동학술대회 발표논문집
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• pp.3-23
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• 2007

King Sejong the Great, his students in Jip-hyeun-jeon school and Choe Sejin, their successor of the sixteenth century, indicated Middle Korean had three distinctive pitches, low, high, and rising (phyeong-, geo-, sang-sheong). Thanks to $Hun-min-jeng-{\emptyset}eum$ as well as its Annotation and side-dots literatures in fifteenth and sixteenth centuries, we can compare Middle Korean with Hamgyeong dialect, Gyeongsang dialect, and extant tone dialects with joint preservers of what was probably the tonal system of unitary mother Korean language. What is most remarkable about middle Korean phonetic work is its manifest superiority in conception and execution as anything produced in the present day linguistic scholarship. But at this stage in linguistics, prior to the technology and equipment needed for the scientific analysis of sound waves, auditory description was the only possible frame for an accurate and systematic classification. And auditory phonetics still remains fundamental in pitch description, even though modern acoustic categories may supplement and supersede auditory ones in tonological analysis. Auditory phonetics, however, has serious shortcoming that its theory and practice are too subject to be developed into the present century science. With joint researchers, I am developping a new pitch scale. It is a semiautomatic auditory grade pitch analysis program. The result of our labor will give a significant breakthrough to upgrade our component in linguistics.