• Title/Summary/Keyword: opening types

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Numerical Flow Visualization of 1st Cycle Motion of a Fling-clapping Wing (프링-크래핑 날개의 첫 번째 사이클 운동에 관한 수치적 흐름 가시화)

  • Sohn, Myong-Hwan;Chang, Jo-Won
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.32 no.7
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    • pp.1-12
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    • 2004
  • A flow visualization of the 1st cycle motion of a fling-clapping wing that might be employed by butterflies during flight is performed. In this numerical flow visualization, he time-dependent Navier-Stokes equations are solved for two wing motion types; 'fling followed by clap and pause' and 'clap followed by fling and pause'. The result is observed regarding the main flow features such as the sequential development of the two families of separation vortex pairs and their movement. For the fling followed by clap and pause motion, a strong separation vortex pair of counter-clockwise develops in the opening between the wings in the fling phase and they then move out from the opening in the following clap phase. For the clap followed by fling and pause motion, the separation vortex pair developed in the outside space in the clap phase move into the opening in the following fling phase. The separation vortex pair in the opening developed in the fling phase of the clap followed by fling and pause motion is observed to be stronger than that in the opening developed in the fling phase of the fling followed by clap and pause motion.

Articulatory Manifestation of Prosodic Strengthening in English /i/ and /I/

  • Kim, Sa-Hyang;Cho, Tae-Hong
    • Phonetics and Speech Sciences
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    • v.3 no.4
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    • pp.13-21
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    • 2011
  • The present study investigated the effects of two different sources of prosodic strengthening, i.e., boundary and accent, in the articulation of English high front vowels, /i/ and /I/. The vowels were investigated in vowel-initial ('eat' vs. 'it'), /h/-initial ('heat' vs. 'hit') and /p/-initial words ('Pete' vs. 'pit'), which were placed in varying prosodic conditions. Using Electromagnetic Articulograph (EMA), the tongue dorsum positions in the x and y dimensions, the lip opening and the jaw opening (lowering) were measured. With respect to the boundary-induced strengthening, results showed that /i/ and /I/ in vowel-initial words ('eat' - 'it') are produced with a higher tongue position in the domain-intial than domain-medial positions. The fact that the vowels only in the vowel-initial condition showed the domain-intial strengthening (DIS) effect suggests that the DIS effect is localized mainly to the initial position (the locality account). As for the accent-induced strengthening, vowels were produced with a more fronted tongue position and larger lip opening in accented than unaccented positions. This suggests that the presence of accent increases overall sonority of the vowels in various prosodic contexts, and enhances primarily the frontedness of the front high vowels. Taken together, the results indicate that the two types of prosodic strengthening are articulatorily realized differently, supporting the view that they are encoded separately in the speech planning process. The present study also showed the distinction between the two high front vowels in the tongue position (in both the frontedness and the height dimensions), while the jaw did not seem to contribute to the distinction robustly, suggesting that the tongue contributes more in distinguishing the two vowels than the jaw does.

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Field Application of High Strength Concrete by Cement Types Using Maturity (적산온도를 이용한 시멘트 종류별 고강도 콘크리트의 현장 적용성)

  • Kim, Dong Baek
    • Journal of the Society of Disaster Information
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    • v.16 no.3
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    • pp.472-478
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    • 2020
  • Purpose: The purpose of the study is to help economic and safe construction by accurately predicting the initial strength of high-strength concrete (70MPa) for each type of cement, securing reliability of concrete quality, and drawing accurately the timing of form deformed, tensioning time of PS concrete, and openning of traffic after road repair with maturity. Method: Calculate the maturity by measuring the hydration heat with cement type for each age, and measure the strength of concrete with age to predict the strength corresponding to the any maturity. Result: In estimating the time required for traffic opening in road repair, ASTM C1074 was theoretically estimated at 16.4 hours for high-strength concrete, but in this study, maturity was calculated at 307, 14.4 hours for OPC and maturity at 2700, 34 hours for LHPC and maturity 200, 8 hours for ESPC. Conclusion: The timing of form deformed of structures using high-strength concrete and the opening of traffic of road repair may be much faster than in the case of concrete using OPC below the design basis strength 40MPa applied by ACI Committee 347.

A Study on the Optimal Selection Method of Screen Mesh for Domestic Halftone Screen Printing (국내 하프톤 스크린 인쇄를 위한 최적의 스크린 망사 선택 방법에 관한 연구)

  • Choi, In-Sik;Cho, Ga-Ram;Koo, Chul-Whoi
    • Journal of the Korean Graphic Arts Communication Society
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    • v.31 no.1
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    • pp.1-14
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    • 2013
  • Screen printing is a printing method with flexible plate surface characteristics. In addition, since the appearance of electronics industry the screen printing has been demanding high quality and definition. However, Screen printing is a method for taking ink through mesh opening because screen mesh tends to restrict quality of screen printing. In particular, the biggest problem compared with other printing type is halftone reproduction characteristics. Halftone reproduction characteristics for screen printing depend on screen mesh and opening. Dot losses or dot gains are observed through various types of screen mesh because thread of screen mesh interfere with the movement of the ink. Excessive dot losses or gains can affect the tonal range. Furthermore, this problem can result in other problem such as bad contrast and gray balance. Therefore, it is an important factor to use proper screen mesh for halftone screen printing. However, domestic screen printing industry relies on worker's experience in field rather than depending on objective data although standardized specifications and optimal printing conditions are required for screen printing. For this reason, it is important to stipulate standard condition for domestic screen printing industry. Therefore, it was examined to find tonal range by mesh opening in halftone prints process of screen printing used domestic paper and ink in this study. In addition, TVI(Tone Value Increase) characteristic was observed by comparing to the manuscripts and prints of the dot area ratio. Furthermore, contrast value and gray balance were confirmed for each condition of the printout. Conditions for the proper selection of screen mesh screen for the quality of the prints were also examined, compared with the international standard of screen printing, ISO 12647-5.

Study of the Parting and Meeting of Yin-Yang on Treatise on on the Parting and Meeting of Yin-Yang in Hwangjenegyeng Somun (소문 음양이합론의 음양이합에 관한 연구)

  • Kim Kwang Joong;Ha Keun Ho
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.18 no.1
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    • pp.8-15
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    • 2004
  • Hwangjenegyeng somun. Treatise on the parting and Meeting of Yin-Yang is the theory of the parting and meeting about Yin-Yang. It is harmonized treatise Yin-Yang and systemic constant. Taechung and Gwangmyeng are the concretely applied form of the parting and meeting of Yin-Yang at human body. The parting and Meeting of Three-Yin- Three-Yang has six types symbols of circulated Yin-Yang. They have Six-meeting space structure as match like up-down, backside and front-side, left-side and right-side. These pairs express symbolized meaning of creation of Saeng-jang-shu-chang and also apply the same things. Somum Treatise on the Parting and Meeting of Yin-Yang explains acting of human body by the parting and meeting of Three-yin-three-yang as six structures of Opening-covering-axis of Three-yin-three-yang. This principal is expression of the parting and meeting of Yin-Yang and concretes the opening and closing of circulation process for symmetry by each acting of Three-yin-three-yang. As result. the match of six-meeting in space structure and the Opening-covering-axis of Three-yin-three-yang are the basic principal of oriental medicine about the treatise of Gyeng-Lak and the treatise of Six-Gyeng of Sanghanlon.

Acoustic emission characteristics during damage-zone formation around a circular opening

  • Jong-Won Lee;Eui-Seob Park;Junhyung Choi;Tae-Min Oh;Min-Jun Kim
    • Geomechanics and Engineering
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    • v.36 no.5
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    • pp.511-525
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    • 2024
  • Underground openings significantly affect the mechanical stability of underground spaces and create damaged zones. This study investigated the acoustic emission (AE) characteristics associated with the formation of damaged zones around circular openings. Uniaxial compression experiments were conducted on three types of rock specimens, namely, granite (GN-1 and GN-2), gabbro (GB), and slate (SL), containing a circular opening. AE and digital image correlation (DIC) techniques were used to monitor and evaluate the damaged zones near the circular openings. The AE characteristics were evaluated using AE parameters, including count, energy, amplitude, average frequency, and RA value. The DIC results revealed that the estimated diameters of the damaged zones of GN-1, GN-2, GB, and SL were 1.66D, 1.53D, 1.49D, and 1.9D, respectively. The average displacements at the surface of the damaged zones for these specimens were 0.814, 0.786, 0.661, and 0.673 mm, respectively, thus demonstrating a strong correlation with Young's modulus. The AE analysis with DIC revealed that tensile failure occurred in the direction parallel to the maximum compression axis as the load increased. Thus, this study provides fundamental data for a comprehensive analysis of damaged zones in underground openings and will facilitate the optimization of rock engineering projects and safety assessments thereof.

Determination and Applications of U and K$_{op}$ for Crack Closure Evaluation under Mixed-mode loading (혼합모드 하중 하에서 균열닫힘 평가에 대한 K$_{op}$와 U의 결정과 적용)

  • Song Samhong;Seo Kijeong;Lee Jeongmoo
    • Transactions of the Korean Society of Automotive Engineers
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    • v.13 no.3
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    • pp.178-185
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    • 2005
  • Crack tip displacement is originated by tensile stress component, s and shear stress component, t on pure Mode I and pure Mode II. The crack tip displacement(CTD) depends on combined types of different two stress components under mixed-mode loading conditions (MMLC). Thus, the analysis of crack tip displacement must be CTD vector, dv which is composition of ds and dt under MMLC. In this paper, various effects of MMLC on the crack closure are studied experimentally. The crack closure magnitude is calculated from the information of crack tip displacement under MMLC. This information has been obtained from the high resolution optical microscope in direct observations of crack displacement behavior at the crack tip. Observed crack tip displacement is analyzed by using CTD vector to determine crack opening load. The various effects of MMLC on the crack closure are explained using crack opening ratio with crack length and mode mixture. The effective stress intensity factor considering crack closure is also discussed.

Preparation of Ceramic Foam Filter and Air Permeability (집진용 세라믹 필터의 제조 및 공기 투과 특성)

  • 박재구
    • Journal of Korean Society for Atmospheric Environment
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    • v.16 no.4
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    • pp.381-388
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    • 2000
  • Ceramic foam prepared with cordierite as a starting material by foam method was tested to evaluate the feasibility as a filter for the dust collection in hot gas. Two different types of agents Benzethonium chloride (BZTC, C27H42NO2Cl) and Sodium Lauryl Sulfate(SLS, CH3(CH2)11OSO3Na) were used as foaming agents in foaming process. Porosityof ceramic foam was about 80% and mean pore size were 100${\mu}{\textrm}{m}$ for SLS agent and 200 ${\mu}{\textrm}{m}$ for BZTC. It was observed that ceramic foam was composed of continuous macro-pore structure with opening windows interconnecting macro-pores. The surface of ceramic foam support of was coated with cordierite particles ranged from 20${\mu}{\textrm}{m}$ to 50${\mu}{\textrm}{m}$ Meso-pore size in the coating layer on ceramic foam was below 10${\mu}{\textrm}{m}$. While air permeability of the support increased with increasing macro-pore size coated ceramic filters showed a constant permeability without regard to the macro-pore size of the support. The permeabuilities of support varied in the range of 600$\times$10-13m2 to 1000$\times$10-13m2. For the case of coated ceramic filter it was about 200$\times$10-13m2. As a result of particle trapping test by using fly ash the particle removal efficiency was over the 99.9%.

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A Research on the Classification of Herbal Medicines based on the Sasang Constitution (Taeumin and Taeyangin Part) (사상(四象) 체질별(體質別) 약재(藥材) 분류(分類) 관한 연구(硏究)(태음인(太陰人) 및 태양인편(太陽人編))

  • Kim, Kyung-Yo;Kim, Jong-Yol
    • Journal of Sasang Constitutional Medicine
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    • v.14 no.1
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    • pp.1-9
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    • 2002
  • We analyzed 44 and 16 types of herbal medicines for Taeumin and Taeyangin, clinically applied in Dongyisoosebowon. In order to discover the standard of herbal classification for the Sasang constitutions, four concepts of Sasang Medicine were applied. These included 'Sadangron (theory of four groups)', 'Seungganggaehap (ascending-descending and gathering-dispersing)', 'Pyorihanyoul (exterior-interior and hot-cold)',and 'Hyungchiaekmi (fragrance, smell, bodily fluid and taste)'. According to these analyzing methods of herbal properties, we have reached the following conclusions: Herbal medicines for 'Taeumin' are characterized by opening energetics that reinforce dispersing Qi. The 'Exterior cold disease' is treated with herbs that ventilate the lungs and disperse dampness in three ways: by moistening the lungs, by releasing exterior, and by resolving dampness. The 'Interior heat disease' is treated with herbs that clear the liver and disperse heat in two ways. One by clearing liver heat through dispersing damp-heat of the small intestine and the other by opening orifices. Herbal medicines for Taeyangin are characterized by those that gather energy inward. They include herbs that treat beriberi, dystrophy of the extremities and vomiting, as well as, fish, shellfish, fruits and vegetable.

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Analysis on the Unbundling of Optical Fiber in Japan (일본의 광파이버 개방정책 분석)

  • 이종용
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2003.10a
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    • pp.565-568
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    • 2003
  • Optical fiber is a kind of local loop types. Most of countries do not still require the incumbent to open his optical fiber network except just a few countries such as US, Japan and Italy. Recently the FCC, the regulator in US, decided to reduce the obligation of its unbundling in order to facilitate the incentive of broadband network investment. And Japan also is reviewing the policy of the fiber' unbundling. So, We needs to take into consideration about the benefit and cost of the opening of optical fiber network in advance. The purpose of this paper is to review the opening policy of optical fiber network in Japan, and to discuss the implication of case study.

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