• Korean Journal of Acupuncture
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• 제30권2호
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• pp.122-130
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• 2013

Objectives : The fact that Primo vessel as a new circulatory system exists in the lymphatic vessels of the rabbits which were treated with sound wave vibration therapy is confirmed with the anatomy of rabbit. Isolated Primo vessel is investigated, particularly focused on morphological features. Methods : Before the anatomy, a rabbit in a cage box was laid on the sound wave vibrating apparatus and then is applied by various frequencies and intensities for 30 min with music that a rabbit likes. Results : Isolation and observation of Primo vessel was easier when the lymphatic circular system was applied at a certain frequency and intensity of 7 Hz and 50. The probability of observation for Primo vessel enhanced to 90%. Conclusions : The sound wave therapy by a vibration apparatus is considered necessary as major process to facilitate the reproducible isolation and observation of Primo vessel.

• 한국유체기계학회 논문집
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• 제1권1호
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• pp.32-40
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• 1998

Aerodynamic performance of a cooling fan of driving motor was enhanced modifying the vane-shroud configuration. Performance of a target model was evaluated to obtain baseline data. The aerodynamic performance and sound pressure level were tested and measured with different numbers of vane of increased length. The tested models show high and stable performance and low values of specific noise level. The long vane-shroud structure induces more stable through flow and decreases the tip leakage flow, which contributes to the increases of performance and efficiency. The sound pressure level increases for the modified model, however, specific noise level decreases.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2007년도 추계학술대회논문집
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• pp.1442-1445
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• 2007

Just noticeable differences (jnds) of autocorrelation function (ACF) parameters - Phi (0), Tau 1 and Phi 1 - of household refrigerator noise were investigated by psychoacoustical analyses. Phi (0) of five refrigerators' noise was changed with equal (${\pm}$) interval level of 0.5-1.0 dB up to five intervals by manipulating sound pressure level of the noise. Tau 1 and Phi 1 were varied with equal (${\pm}$) interval of around 0.10 ms and 0.02, respectively. Pitch shifting and strengthen methods were applied for the Tau 1 and Phi 1 variations. As results of subjective evaluations, about 2.0 dB was shown as jnd of Phi (0). The values of 0.30 ms and 0.06 were found as jnds of Tau 1 and Phi 1, respectively. The jnd results of each ACF parameter can be applied to explain substantial amount of sound quality (SQ) enhancement in the SQ prediction indices which were proposed in the authors' previous study [Sato et al. (2007) J. Acoust. Soc. Am.].

• 한국정보통신학회논문지
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• 제17권2호
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• pp.280-286
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• 2013

본 논문에서는 지능형 TV의 음성인터페이스를 위한 잡음제거 시스템에 대해서 제안한다. 음성인식 성능 저하에 매우 나쁜 영향을 주는 TV 소리를 제거하기 위해서 TV 소리 자체를 참조 잡음으로 하는 잡음제거 알고리즘이 구현된다. 제안된 알고리즘에서 TV 스피커와 다채널 장비간의 전달함수를 추정한다. 그 후, 위너 필터를 동작시키기 위해서 잡음의 전력 스펙트럼이 추정된다. 추가적으로 후처리 과정이 적용되어 잔존 잡음을 제거한다. 실험의 의해서 제안된 알고리즘이 5 dB 입력 SNR에서 88 %의 음성인식률을 나타내었다.

• 한국정보통신학회논문지
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• 제3권3호
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• pp.541-546
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• 1999

자유 공간에서 음원으로부터 사람의 귀로 음향적인 전단 과정을 표현하는 머리전달함수는 사람이 음원의 위치를 판단할 수 있는 중요한 정보를 포함하고 있으며, 이를 이용하여 실질적으로는 존재하지 않는 음원을 근사적으로 생성할 수 있는 입체 음향 시스템을 구현할 수 있다 그러나 개인의 것이 아닌 일반적인 머리전달함수를 사용함으로 인해 앞뒤 판정 오차, 고도 판정 오차와 같은 음상 정위 능력이 저하된다. 이 논문에서는 머리전달함수의 스펙트럼 놋치(notch) 레벌을 증가시켜 수직면상에서의 앞뒤 판정 오차와 고도 판정 오차를 줄였다. 제안된 방법의 성능을 정지된 음원과 움직이는 음원에 대하여 주관 평가를 통해 증명하였다.

• KIEAE Journal
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• 제3권3호
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• pp.27-34
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• 2003

As a result of supply-oriented housing policy of Korea since the 1960s, the number of apartment housing units has increased up to six million as of the end of 2001 that is 55% of total housing units. Although the needs of placid living environment increases according to the enhancement of residents' living standard, most of construction firms as apartment suppliers plan and design apartment buildings to maximize the profit and give rise the residents' petitions and troubles about floor impact noise. In consequence, the floor impact noise becomes one of principal problems of living environment, and the government placed the obligation of installing the noise isolation materials between upper and lower floors in 2001 and controlling the floor impact noise lower than 60dB from the middle of 2004. In other to provide the fundamental research data to enhance the reduction performance of floor impact sound, in this paper, the factors that influence on the floor impact noise are derived from the survey of many research papers and the performance of various materials used as noise reduction objects are compared and surveyed with the factors in the experiments in field and laboratory.

• 한국정보통신학회논문지
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• 제22권12호
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• pp.1659-1666
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• 2018

입력된 소리가 음성과 음향이 혼재된 경우 잡음의 영향으로 음성 인식률이 저하됨을 알 수 있으며 S/W적 처리 한계를 극복코자 H/W 장치인 MEMS 장치를 개발하여 음성 인식률을 향상시켰다. MEMS 마이크로폰 장치는 음성을 입력하는 장치로서 다양한 모양으로 구현되어 사용된다. 기존 MEMS 마이크로폰은 일반적으로 우수한 성능을 발휘하나 잡음 과 같은 특수 환경에선 음성과 음향이 혼재되어 처리 성능이 저하되는 문제점이 발생됨을 알 수 있었다. 이러한 문제점을 개선코자 초기 입력장치에 음성 특성을 구분하여 검출할 수 있는 신규 고안된 MEMS 장치를 사용하여 향상시켰다.

• 콘크리트학회논문집
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• 제15권4호
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• pp.566-573
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• 2003

본 연구에서는 기포콘크리트속에 연속공극율을 증가시켜 흡음률을 높이면서 강도를 증진시킨 강체형 흡음재의 제조를 목적으로 하였다. 실험결과, 기포첨가량을 증가시켜 연속공극률을 높일수록 흡음률이 증가하였으며, 재료두께 5cm인 경우 연속공극률 40%이상에서 평균흡음률 70%이상을 만족하였다. 또한 흡음재 두께의 증가는 중저음영역에서 흡음률 증가를 나타내었으며 평균흡음률 70%이상을 만족하는 기포콘크리트의 비중은 재료두께 5cm에서 0.4이하, 7cm에서 0.6이하로 나타났다. 그리고 평균흡음률 70%이상 만족하는 비중 0.4인 기포콘크리트의 압축강도는 시멘트분말도 3,000$\textrm{cm}^2$/g의 경우 1.37MPa이나, 시멘트분말도 8,000$\textrm{cm}^2$/g에서는 3.34MPa로 증가되었다. 따라서, 연속공극을 갖는 기포콘크리트의 압축강도는 시멘트분말도가 높을수록 증가하는 것으로 사료된다.

• 센서학회지
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• 제28권6호
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• pp.360-365
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• 2019

A polyvinylidene fluoride (PVDF)-based film speaker is successfully fabricated with enhanced bass sound by incorporating buckled nanospring carbon nanotubes (NS-CNTs) as fillers. Various concentrations up to 1-7 wt% of uniformly dispersed buckled NS-CNTs are loaded to increase the beta (β)-phase fraction, crystallinity, and dielectric constant of the speaker, and this results in the bass part enhancement of about 19 dB full scale (dBFS) at 7 wt% filler loading of the piezoelectric film speaker.

• 대한간호학회지
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• 제35권6호
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• pp.991-1003
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• 2005

Purpose: This paper reports a randomized controlled trial to investigate the effects of a Marital-relationship enhancement program(MREP) for marital couples. Methods: Volunteer couples from several well-being centers in Seoul were randomly assigned either to a treatment group (n=36), participating in a MREP based on Gottman's 'sound marital house' theory, or to a control group (n=35) receiving no treatment. The content of the MREP was provided to the control group after the research was completed. Data was collected from December 2003 to May 2004 using modified versions of the inventories developed by Gottman on marital satisfaction, positive affect, conflict regulation, and communication barriers. Results: Participants in the experimental group showed significant improvements in marital satisfaction, positive affects, conflict regulation, and communication-barrier scores compared to the control group. Conclusion: The present program for marital-relationship enhancement is helpful in enhancing marital relationships and regulating conflict between marital couples and, ultimately, may be useful to prevent divorce.