• Title/Summary/Keyword: Nature Sound

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Improvement of Strength in ALC using Admixtures and Grain Size (혼합재 및 입도에 따른 경량기포콘크리트의 강도특성 개선)

  • Kim, Young-Yup;Song, Hun;Lee, Jong-Kyu;Chu, Yong-Sik
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2007.11a
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    • pp.79-82
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    • 2007
  • Recently, the use of ALC has became increasingly popular. ALC is a unique building material. Because of its cellular nature, it is lightweight, self-insulating, sound and fireproof, as well as insect and mold resistant. Furthermore, ALC is free of VOCs and various fibers associated with wood and glass wool construction. However, ALC have high water absorption, low compressive strength and popout the origin of the low surface strength in its properties. These properties make troubles under construction such as cracking and popout. Thus, this study is to improve the fundamental strength by controls of increasing of admixtures, and grain size. Admixtures make use of metakaolin, silica fume, sodium silicate and sodium hydroxide. From the test result, the ALC using admixture have a good fundamental properties compared with plain specimen. Compressive strength, specific strength and abrasion's ratio were improved depending on increasing admixtures ratio's, and grain size.

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An Experimental Study on the Properties of EPS Concrete according to the Variation of Mix Design (배합조건에 따른 경량 EPS 콘크리트의 물리적 특성에 관한 실험적 연구)

  • Lee, Jung-Koo;Jung, Eun-Hye;Gang, Cheol;Cho, Sung-Hyun;Jeong, Gab-Cheol;Kim, Jin-Man
    • Proceedings of the Korea Concrete Institute Conference
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    • 2006.11a
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    • pp.833-836
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    • 2006
  • The purpose of study is to develope for lightweight concrete panel which have high quality with insulation performance of sound. The use of lightweight concrete products has been increased at a recently high structures. Also, the gathering of nature aggregate is limited, so that lack of fine aggregate is appearing. Statistical analysis is practiced on the properties of EPS concrete according to the variation of mix design. As a result saturated density is affected by amount of Bottom ash.Also compressive strength is affected by W/B ratio at the early age and amount of Bottom ash at the latter age.

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The Home Education through Pu-lei본s letters (<傅雷家書>를 통해서 본 家庭敎育(觀))

  • 지영숙
    • Journal of Family Resource Management and Policy Review
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    • v.5 no.2
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    • pp.59-67
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    • 2001
  • Pu-lei is a well-known translator in Chinese literature. He had delivered his experience, knowledge and paternal love to his son who was studying abroad, by hundreds of letters from 1954 to 1966. These letters are appreciated as the perfect expression for paternal love and concerns. Although he had experienced both cultures of the West and the East, his lessons for son are rooted in the oriental‘sprit training’. What he emphasized in his letters is that one should put sound personality first than merely enhancing abilities. Especially, he valued the recreation from meditation and living up to one's belief. Furthermore, he had taught his son to observe the properties, to manage time, and pride of his country and patriotism. The modern family education has overlooked the enhancement of human nature. The egoistic and jaundiced parental love and over-protectiveness led the disorder and the absence of morality today. In this point, the lessons from Pu-lei's letter will give us important suggestions.

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Prediction of Aeroacoustics Noise of Pantograph via Low Speed Wind Tunnel Test and Flow Simulation (저속풍동실험 및 유동해석을 통한 고속전철 판토그라프의 유동소음 해석)

  • 조운기;이종수
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2001.11b
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    • pp.1207-1214
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    • 2001
  • The paper deals with the computational approach in analysis and design of pantograph panhead strips of high-speed railway in aerodynamic and aeroacoustic concerns. Pantograph is an equipment such that the electric power is supplied from catenary system to train. Due to the nature of complexity in high-speed fluid flow, turbulence and downstream vortices result in the instability in the aerodynamic contact between panhead strips and catenary system, and consequently generate the considerable levels of flow-induced sound. In this paper, based on the preceding low speed wind-tunnel test and simulations, the aerodynamic and aeroacoustic characteristics in low speed are analyzed.

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An Assessment Model on Sustainability of Local City (지방도시의 지속가능성 평가모형)

  • Hong, Young-Rok;Kwon, Sang-Zoon;Myung, Hyun
    • Journal of the Korean Institute of Landscape Architecture
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    • v.27 no.4
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    • pp.1-12
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    • 1999
  • This study aims to find basic data for using the quantitative assessment of the sustainability and establishing the systematic index of the planning for local cities to consider the environmentally sound and sustainable development. The research designs to review professional responding to surveys preceded by separate questionnaires and interviews from book reviews, and suggests to make an assessment model of the sustainability for local cities. The research found consequently as follows. Firstly, the research survey items were decides totally 52, grouped 9 assessmental issues and distributed under 4 assessmental domains for the sustainability from the references of book reviews. Secondly, the research result concentrated on the followings from the professional responding to surveys. 1. A most influent factor is the distribution of animals and plants in a nature domain. The next influent factors are the ratio of mass-transportation systems, the numbers of the species of animals and plants, the acreage of conservative forestry, the numbers of reused water resources, and the usage number of water supply, orderly in the nature domain. 2. A most influent factor is the usage number of synthetic detergents in a pollution domain. The next influent factors are the volume of waste water, the number of registered vehicles, the degree of soil pollution, and the charge of development imposition, orderly in the pollution domain. 3. A most influent factor is the acreage of athletic facilities, in an urban domain. the next influent factors are the acreage of recreational facilities, the number and acreage of cultural assets, the number of cultural facilities, the acreage of landscape conservation area, the charge of cultural asset management, orderly in the urban domain. 4. A most influent factor is the number of waste disposal facilities in a participation domain. The next influent factors are the capacity of reused waste, the usage of synthetic detergents, the ratio of waste water disposal, orderly in the participation domain. 5. A most contributed influent domain to the assessment of the sustainability for local cities is the urban domain. The next influent domains are nature domain, participation domain, and pollution domain, orderly in the contribution of the assessment of the sustainability. But, the pollution domain is little relationship with the sustainability. Therefore, it is clear that the abundant greens and the improved level of culture are dominant influences on the sustainabiligy, as like improving the ratio of roadside trees, the acreage of parks, and enlarging the number of cultural facilities.

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Analysis of Coen Brothers's Directing Style: Centering around Crime Movies (코엔 형제의 연출 스타일 분석 :범죄 영화를 중심으로)

  • Lee, Jeong-Gook
    • The Journal of the Korea Contents Association
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    • v.10 no.6
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    • pp.236-248
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    • 2010
  • Through this thesis, I analyzed Coen brothers's directing style centering around Crime movies: Blood simple, Barton Fink, Fargo, The man who wasn't thers, No country for old man. About directing style of Coen brothers, plot is an epic depiction, habitual use of narration, refusal of happy ending. They concern subject matters about human original nature and tragedy by greed. And as motifs, they often use misunderstanding, crossing over, chase. Also they likes characters of ordinary people who is destroyed by greed. How about their technical style? They usually use steady-cam and wide lens in camera, and in his early crime movies he used expressionistic lights, but after that they usually used realistic natural lights. About sound, they likes more sound effects than music. Also they directed realistic acting and emphasized actor's personality. Coen brothers has been directed many crime movies and comedy films. But their unique directing style was particularly outstanding in the crime movies

DIAGNOSIS OF EARLY CARIES WITH DYE-ENHANCED LASER FLUORESCENCE (레이저 형광과 광활성제를 이용한 초기 우식증의 진단)

  • Lee, Sang-Ho;Han, Kuk-Jae;Lee, Chang-Seop
    • Journal of the korean academy of Pediatric Dentistry
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    • v.30 no.1
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    • pp.1-9
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    • 2003
  • To evaluate the quantitative nature of laser fluorescence(LF) and dye-enhanced laser fluorescence(DELF) on early enamel caries, artificial caries were induced on the bovine enamels and argon laser was irradiated on the surfaces of lesions. Fluorescence radiance from enamel specimen was recorded with CCD camera which was connected to PC image analyzing system. The difference of fluorescence of radiance(DFR) between the carious and the sound enamel in each sample of the LF and the DELF groups were measured by image analyzing program. The DFR of lesion surfaces measured with laser fluorescence and lesion depths were evaluated and the results are as follows: The caries lesions were discriminated from sound enamels by the darkness with LF and by the brightness with DELF. The DELF was more sensitive than the LF at the earlier stage of demineralization.

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One-Sided Nondestructive Evaluation of CFRP Composites By Using Ultrasonic Sound (초음파를 이용한 CFRP 복합재의 일방향 비파괴 평가)

  • Im, Kwang-Hee;Zhang, Gui-Lin;Choi, Sung-Rok;Ye, Chang-Hee;Ryu, Je-Sung;Lim, Soo-Hwan;Han, Min-Gui;Hsu, David K.
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.20 no.1
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    • pp.47-52
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    • 2011
  • It is well known that stiffness of composites depends on layup sequence of CFRP(carbon fiber reinforced plastics) laminates because the layup of composite laminates influences their properties. Ultrasonic NDE of composite laminates is often based on the backwall echoes of the sample. A pair of such transducers was mounted in a holder in a nose-to-nose fashion to be used as a scanning probe on composites. Miniature potted angle beam transducers were used (Rayleigh waves in steel) on solid laminates of composites. Experiments were performed to understand the behavior of the transducers and the nature of the waves generated in the composite (mode, wave speed, angle of refraction). C-scan images of flaws and impact damage were then produced by combining the pitch-catch probe with a portable manual scanner known as the Generic Scanner ("GenScan"). The pitch-catch signal was found to be more sensitive than normal incidence backwall echo of longitudinal wave to fiber orientation of the CFRP composites, including low level porosity, ply waviness, and cracks. Therefore, it is found that the experimentally Rayleigh wave variation of pitch-catch ultrasonic signal was consistent with numerical results and one-side ultrasonic measurement might be very useful to detect the defects.

Assessment of statistical sampling methods and approximation models applied to aeroacoustic and vibroacoustic problems

  • Biedermann, Till M.;Reich, Marius;Kameier, Frank;Adam, Mario;Paschereit, C.O.
    • Advances in aircraft and spacecraft science
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    • v.6 no.6
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    • pp.529-550
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    • 2019
  • The effect of multiple process parameters on a set of continuous response variables is, especially in experimental designs, difficult and intricate to determine. Due to the complexity in aeroacoustic and vibroacoustic studies, the often-performed simple one-factor-at-a-time method turns out to be the least effective approach. In contrast, the statistical Design of Experiments is a technique used with the objective to maximize the obtained information while keeping the experimental effort at a minimum. The presented work aims at giving insights on Design of Experiments applied to aeroacoustic and vibroacoustic problems while comparing different experimental designs and approximation models. For this purpose, an experimental rig of a ducted low-pressure fan is developed that allows gathering data of both, aerodynamic and aeroacoustic nature while analysing three independent process parameters. The experimental designs used to sample the design space are a Central Composite design and a Box-Behnken design, both used to model a response surface regression, and Latin Hypercube sampling to model an Artificial Neural network. The results indicate that Latin Hypercube sampling extracts information that is more diverse and, in combination with an Artificial Neural network, outperforms the quadratic response surface regressions. It is shown that the Latin Hypercube sampling, initially developed for computer-aided experiments, can also be used as an experimental design. To further increase the benefit of the presented approach, spectral information of every experimental test point is extracted and Artificial Neural networks are chosen for modelling the spectral information since they show to be the most universal approximators.

Development and Application of Robot Contents for Symbolic Vocal Language Learning of Young Children (상징적 음성언어 교육을 위한 유아 로봇 콘텐츠 개발 및 적용)

  • Kim, Jeong-Ho;Han, Jeong-Hye;Kim, Dong-Ho
    • Journal of The Korean Association of Information Education
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    • v.13 no.2
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    • pp.205-214
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    • 2009
  • The vocal language which is a symbolic vocal language described external sounds or expressed shape of things in nature, phenomenon, movement, shape of state provided images which can be envisioned in minds and created the mood for the whole writings. As the instructive ways of symbolic vocal language, the activities which refrain one-way translation for lexicon definition and stimulate the thoughts of students and interesting activities such as songs and comic books which students can understand by themselves are needed. Therefore, in this study, these symbolic vocal language is to be developed as the contents of robot for Symbolic Vocal language learning activities and after study activities, the possibility of using robot for education is to be reviewed, comparing changes in definitive areas and achievement after study activities. After the Symbolic Vocal language learning activities using robot and computer, as results of testing three achievement types of words simulated sound, shape, and movement, in study on words simulating sound and shape there was no significant difference. But The study activities simulating words used robot showed significant difference in terms of interest, confidence, and understanding.

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