• Journal of the Korean Wood Science and Technology
• /
• v.46 no.2
• /
• pp.149-154
• /
• 2018

The changes in sound absorption capability and air permeability of Malas wood after high temperature heat treatment were investigated. The average air permeability of Malas in longitudinal direction after heated under the temperature of $190^{\circ}C$ during 3 hours was about 23.48 darcys and that of control was about 3.11 darcys. The noise reduction coefficients of Malas specimens were 17% for treatment and 10% for control. The means of sound absorption coefficient of specimens in the frequency range of 50~6,400 Hz were 42% for treatment and 17% for control, respectively.

• Fibers and Polymers
• /
• v.1 no.1
• /
• pp.59-65
• /
• 2000

In order to investigate psychoacoustic characteristics of fibers, and to compare them with sound physical parameters, each sound of 25 different fabrics consisted of a single fiber such as wool, cotton, silk, polyester, and nylon was recorded. Sounds of specimens were transformed into critical band diagram and psychoacoustic characteristics including loudness and sharpness for each sound were calculated based on Zwicker＇s models. Physical parameters such as the level pressure of total sound (LPT), level ranges (ΔL), frequency differences (Δf), AR coefficients (ARC, ARF, ARE) were obtained in fast fourier transform (FFT) spectrum. Nylon taffeta showed higher values for loudness than 2.5 sone corresponding to human low conversation, while most silk fibers generated less louder showing lower values for loudness than 1.0 sone. Wool fibers had higher loudness mean value than that of cotton, while the two fibers didn't differ in LPT. Loudness showed high positive correlation coefficients with both LPT and ARC. Sharpness values were higher for wool fiber group than other fibers. Sharpness was not concerned with loudness, LPT, and ARC, but the fabrics with higher values for sharpness tended to show higher ΔL.

• Journal of Multimedia Information System
• /
• v.9 no.1
• /
• pp.43-50
• /
• 2022

As the discourse on Anthropocene grows, this exploratory research investigates the interrelationship and interconnectivity between humanity and technology by analyzing a sound art installation created by the author. Crying Sea is a sound installation that uses plastic wastes collected from the shore to create symbolic narratives and artistic experience connecting humans, objects, and nature through interactive digital technology. In this installation, the audiences are guided to walk over the wastes, and the sounds created by the footsteps are recorded in real-time, which then are distorted and amplified into disturbing sounds through speakers filling up the room. In analyzing this artwork, three theories from technological, philosophical, and ecological backgrounds were used; specifically, Bernard Stiegler's pharmakon theory, Dona Haraway's cyborg manifesto, and Timothy Morton's dark ecology theory. A common factor revealed from all three theories by analyzing the Crying Sea is that humans, technologies, and all other entities within nature are interconnected and resonated. The awareness of this recursive relationship allows us to consider sustainable balancing.

• Korean Journal of Environment and Ecology
• /
• v.30 no.3
• /
• pp.344-352
• /
• 2016

The goal of this study was to identify the water temperature and sound environment of oviposition sites of the Huanren brown frog (Rana huanrensis), which breeds in valleys in early spring. The study was conducted in Chiak National Park, central Korea, between March 23 and April 24, 2015. Correlation analysis of the physical factors of oviposition sites revealed that the number of egg clutches was positively correlated (p < 0.05) with the water temperature and negatively correlated (p < 0.05) with the sound volume of the oviposition sites. However, no correlation was found between clutch number and the total area or depth of water. The water temperature of the oviposition sites was $2.2^{\circ}C$ higher on average than that of the mainstream (p < 0.001). To avoid the low early spring temperatures, R. huanrensis spawned in sites with accumulated water, in which the depths were less than 10cm and the temperature was relatively high. Further, eggs were spawned in clusters in small spaces to maximize the thermal insulation effect. In terms of noise levels, oviposition sites were found to be 6.9 dB quieter than the mainstream (p<0.001). In conclusion, R. huanrensis was found to spawn in warm, quiet, and small oviposition sites in valleys to avoid low early spring temperatures and loud water noise. This study is significant because it is the first to characterize the sound environment of amphibian oviposition sites.

• Journal of the Korean Wood Science and Technology
• /
• v.47 no.3
• /
• pp.290-298
• /
• 2019

The sound absorption coefficient and transmission loss of several types of rice hull mats with varying apparent densities and thicknesses are estimated in this paper using the transfer function and matrix methods, respectively, to evaluate the possibility of using rice hull as an acoustic construction material. The mean sound absorption rates of 10-cm-thick rice hull mats with target densities of $0.10g/cm^3$, $0.12g/cm^3$, and $0.14g/cm^3$ were 0.91, 0.92, and 0.95, respectively, while those of the 1-cm-thick plywood attached to the back of the rice hulls were 0.90, 0.92, and 0.92, respectively. The means of the sound transmission loss of the 10 cm-thick rice hull mats with the target densities of $0.10g/cm^3$, $0.12g/cm^3$, and $0.14g/cm^3$ were 7.66 dB, 10.49 dB, and 14.14 dB, respectively, while those of the 1 cm-thick plywood attached to the back of the rice hulls were 33.34 dB, 36.72 dB, and 38.95 dB, respectively. In conclusion, a rice hull mat could be used as acoustic construction materials because of its high sound absorption coefficient and sound transmission loss.

• Journal of the Korean Wood Science and Technology
• /
• v.39 no.4
• /
• pp.326-332
• /
• 2011

Radial variation of sound absorption capability and air permeability of yellow poplar (Liriodendron tulipifera) wood in cross sectional surface and effect of steam explosion treatment were estimated by the two microphone transfer function method and the capillary flow porometry, respectively. The sound absorption coefficients of steam explosion treated wood was higher than those of control wood and these values increased with frequency. Abundant and big vessel may behave as sound absorbing pore observed on the cross sectional surface of yellow poplar wood. The sound absorption coefficients and air permeability of sapwood were higher than those of heartwood for Liriodendron tulipifera.

• KIEAE Journal
• /
• v.8 no.3
• /
• pp.43-50
• /
• 2008

The aim of this study is to search for the meaning and direction of sound environment preservation in Korea through the concept of soundscape. In order to achieve the goals, it was analyzed the similarities and differences on the contents of "100 The beautiful sounds of Korea - 1999" and "100 Soundscapes of Japan - 1996" in view of the intents of selection, the process of selection, and the construction of the results. The result show that there are the both similarities and differences on the intent and the process of selection, types and extent of sound samples, interactions among human-sound environment-region, the identities of the regions as well as the recognized sound environment. Also, the result shows that it is very important to preserve ecological, social, and cultural sound environment of the region. In order to practice this ideology of soundscape in Korea, there is a necessity for converting people's consciousness and participating voluntary residents' movement.

• Journal of the Korean Society of Clothing and Textiles
• /
• v.25 no.9
• /
• pp.1593-1602
• /
• 2001

본 연구는 스포츠 아우터웨어용 나일론 직물의 소리에 대한 주관적 감각과 이에 관련된 객관적 측정치를 규명하기 위하여, 서로 다른 8종의 나일론 직물의 소리의 스펙트럼 파형을 고찰하였으며, 소리 파라미터로 총음압(level pressure of total sound, LPT),세 가지 AR (autoregressive)계수, Zwicker의 심리음향학적 모델에 따른 크기(Z)와 날카로움(Z)를 계산하였고, Kawabata Evaluation System(KES)으로 직물의 물리적 성질을 측정하였다. 주관적 감각 평가를 위하여 피험자에게 녹음된 각 직물소리를 들려주어 7개 소리 감각 (부드러움, 시끄러움, 날카로움, 맑음, 거 침, 높음, 유쾌함)을 의미분별척도로 답하게 한 후, 단계적 선형 회귀식을 이용하여 직물 소리의 주관적 감각에 대한 예측 모델을 제시하였다. 울트라스웨이드를 제외한 태피터 나일론 직물들은 스펙트럼 파형 에서 다른 조성 섬유의 직물들보다 음압 값이 높고, 총음압이 60dB 안팎의 값을 보여, 착용자에게 불쾌감을 줄 것으로 예상되었으며, 주관적 감각 평가에서도 소리의 부드러움과 맑음, 유쾌함에서 음의 점수를, 시끄러움과 날카로움, 거침, 높음에서 양의 점수를 얻었다. 주관적 감각의 예측모델에서 총음압은 시끄러움과 거침에 정적 영향을, 유쾌함에 부적 영향을 미쳐서 나일론 직물 소리의 총음압이 50dB 이하일 때 주관적으로 유쾌하게 느껴지는 것으로 나타났다.

• Science of Emotion and Sensibility
• /
• v.9 no.1
• /
• pp.39-48
• /
• 2006

This study was carried out to investigate sound sensation of Korean traditional silk fabrics with similar sound pressure levels (SPL) and to identify secondary physical factors excluding SPL which determine sound sensation of the fabrics. Sounds of the silk fabrics tended to be perceived differently from one another as for some of sensation such as clearness ant roughness. They were felt more strongly in aspects of loudness, roughness, and highness than of softness, sharpness, clearness, and pleasantness. Subjective clearness, roughness, and highness were significantly correlated with some of sound parameters including roughness(z), ${\Delta}L,\;and\;{\Delta}f$. Especially, both of clearness and roughness which were varied among the fabrics were found as determined by ${\Delta}L$. This result means that ${\Delta}L$ as well as roughness(z) and ${\Delta}f$ could be utilized secondary to SPL in order to satisfy some of human sensibility for sound from traditional silk fabrics without variation of physical loudness.

• Korean Journal of Environment and Ecology
• /
• v.12 no.1
• /
• pp.78-90
• /
• 1998

An objective of this study was to provide database for the planting disign of buffer green space. Types, planting structure, and effect of vuffer green space were investigated in five housing complexes of newtown of metropolitan area, Korea. Buffer green space in the study sites were constructed as mounding, slope, and plate. The number of species was found 20 tree and sub-tree species(10 evergreen and 20 deciduous species ) and 13 shrub species. These species were planted in one-storyed planting structure and there was no difference with ornamental species in the urban parks. Effect of sound proof by the buffer green space was recognized but sound level in four types among the seven types was observed above standard sound level for housing complex(65dB). Effect of sound proof was especially most effective in the mounding type. It was found that planting density and index of plant crown volume were mot satisfied to the function of buffer green space because of lower density and crown volume than natural vegetation per unit. Based on these results, this study suggested that buffer green space is desirable to be developed in the mounding type over two meters height with multi-layer planting model. In addition, there is needed to consider vegetation structure of natural forest around the developing site.