• Title/Summary/Keyword: open-chain

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3D Casing-Distributor Analysis for Hydraulic Design Application

  • Devals, Christophe;Zhang, Ying;Dompierre, Julien;Vu, Thi C.;Mangani, Luca;Guibault, Francois
    • International Journal of Fluid Machinery and Systems
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    • v.8 no.3
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    • pp.142-154
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    • 2015
  • Nowadays, computational fluid dynamics is commonly used by design engineers to evaluate and compare losses in hydraulic components as it is less expensive and less time consuming than model tests. For that purpose, an automatic tool for casing and distributor analysis will be presented in this paper. An in-house mesh generator and a Reynolds Averaged Navier-Stokes equation solver using the standard $k-{\omega}$ shear stress transport (SST) turbulence model will be used to perform all computations. Two solvers based on the C++ OpenFOAM library will be used and compared to a commercial solver. The performance of the new fully coupled block solver developed by the University of Lucerne and Andritz will be compared to the standard 1.6ext segregated simpleFoam solver and to a commercial solver. In this study, relative comparisons of different geometries of casing and distributor will be performed. The present study is thus aimed at validating the block solver and the tool chain and providing design engineers with a faster and more reliable analysis tool that can be integrated into their design process.

A trend of Open rounded back /a:/ distribution in American English (미국영어에서의 후설원순저모음의 사용분포와 확산추이)

  • Park, Choong-Yon
    • Lingua Humanitatis
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    • v.8
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    • pp.313-329
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    • 2006
  • In some American English dialects, the vowels /a:/ or /c:/ have been replaced with /a:/, as in caught /ka:t/ dog /da:g/ that were pronounced in /kc:t/, and /dc:g/ previously. General American does not have /a:/ in its vowel system. But in East American and Western Pensylvania, cot and caught are homophones, /ka:t/, and similarly with other pairs such as collar vs. caller, stock vs. stalk, don vs. down, knotty vs. naughty. The use of /a/ or /c/ is quite unstable, and is a well-known diagnostic for distinguishing the northern speech area of the United States from the midland and southern area. For an increasing number of Americans, however, entirely lack the opposition between /a/ and /c/, merging to /a/, referring to 'both' of the vowels of lot. This paper investigates the use of /b:/ in American dialects and its relationship with /a:/, /c:/ in AE, and with short /a/ in RP. Examining the isoglosses of the use of /a:/ in various databases of the phonological atlas of North America, this paper discusses the use, position, and trend of merger to /a:/ from the vowels of /a:/ and /c:/ in Current American English.

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Extraction and Bioassay of Allelochemicals in Jerusalem Artichoke

  • Sungwook Chae;Lee, Ho-Jin
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.46 no.4
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    • pp.309-316
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    • 2001
  • Helianthus tuberosus has been known to inhibit the growth of weeds and other plants sharing its habitat. This study was conducted to identify the allelochemicals of Helianthus tuberosus which were extracted with water and solvents. Aqueous extracts of leaf, stem, root, tuber and tuber peel of Helianthus tuberosus except tuber did not show significant differences in phytotoxicity to alfalfa seedlings. It was considered that Helianthus tuberosus contained fewer or less potential water-soluble substances that were toxic to alfalfa. Methanol extract of leaves of Helianthus tuberosus was sequentially partitioned in increasing polarity with n-hexane, ethylacetate and n-butanol. Each extract had a yield of 148, 12, 15.7 and 9.5g, respectively. Inhibitory effects on germination of alfalfa seeds treated with four fractions were not significantly different. But the significant reductions on hypocotyl length were observed for all the solvent extracts. Among the four fractions, the ethylacetate fraction showed the most significant inhibition effect on bioassay with alfalfa. Further separation of the active ethylacetate fraction by open column chromatography led to the 25 subfractions. In bioassay of each sub-fraction with alfalfa seeds, sub-fraction No. 13 showed the most inhibitory effect on seedling growth. $^1$H NMR and gas chromatography-mass spectrometry analysis revealed that sub-fraction No. 13 was the mixture of straight-chain saturated fatty acids.

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Lumbar stabilization exercises using the sling system (슬링(sling) 시스템을 이용한 요부 안정화 운동)

  • Kim, Suhn-Yeop;Kwon, Jae-Hoak
    • The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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    • v.7 no.2
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    • pp.23-39
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    • 2001
  • Dysfunction of the anterior and dorsal muscles of the trunk have been studied in relation to low back pain of many years. Many muscles of the trunk are capable of contributing to the stabilization and protection of the lumbar spine, recent evidence has suggested that transversus abdominis may be critically involved and has been the focus of rehabilitation. The delay in onset of contraction of trunk muscles associated with movement of the upper or lower limb in patients with low back pain indicates a significant deficit in the automatic motor command for control of disturbance to the spine. The function of transversus abdominis has been largely ignored in the evaluation of spinal stabilization and protection. The most essential stabilizing muscles for the lumbar column are the transversus abdominis and the multifidus. Sling exercise therapy(SET) concept consists of a system of diagnosis and treatment. The system of diagnosis involves testing the muscle's tolerance through progressive loading in open and close kinetic chains. The SET system contains elements such as relaxation, increasing the range of movement, traction, training the stabilizing musculature, sensorimotor exercises, training in open and close kinetic chains, dynamic training of the mobilizing musculature, cardiovasc+ular exercises, group exercise, personal exercise at home. Sensorimotor training is an essential element of the SET concept. The emphasis is on closed kinetic chain exercises on an unstable surface, thereby achieving optimum stimulation of the sensorimotor apparatus.

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An Open Standard-based Terrain Tile Production Chain for Geo-referenced Simulation

  • Yoo, Byoung-Hyun
    • Korean Journal of Remote Sensing
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    • v.24 no.5
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    • pp.497-506
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    • 2008
  • The needs for digital models of real environment such as 3D terrain or cyber city model are increasing. Most of applications related with modeling and simulation require virtual environment constructed from geospatial information of real world in order to guarantee reliability and accuracy of the simulation. The most fundamental data for building virtual environment, terrain elevation and orthogonal imagery is acquired from optical sensor of satellite or airplane. Providing interoperable and reusable digital model is important to promote practical application of high-resolution satellite imagery. This paper presents the new research regarding representation of geospatial information, especially for 3D shape and appearance of virtual terrain. and describe framework for constructing real-time 3D model of large terrain based on high-resolution satellite imagery. It provides infrastructure of 3D simulation with geographical context. Web architecture, XML language and open protocols to build a standard based 3D terrain are presented. Details of standard-based approach for providing infrastructure of real-time 3D simulation using high-resolution satellite imagery are also presented. This work would facilitate interchange and interoperability across diverse systems and be usable by governments, industry scientists and general public.

Shadow Economy, Corruption and Economic Growth: An Analysis of BRICS Countries

  • NGUYEN, Diep Van;DUONG, My Tien Ha
    • The Journal of Asian Finance, Economics and Business
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    • v.8 no.4
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    • pp.665-672
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    • 2021
  • The paper examines the impact of shadow economy and corruption, along with public expenditure, trade openness, foreign direct investment (FDI), inflation, and tax revenue on the economic growth of the BRICS countries. Data were collected from the World Bank, Transparency International, and Heritage Foundation over the 1991-2017 period. The Bayesian linear regression method is used to examine whether shadow economy, corruption and other indicators affect the economic growth of countries studied. This paper applies the normal prior suggested by Lemoine (2019) while the posterior distribution is simulated using Monte Carlo Markov Chain (MCMC) technique through the Gibbs sampling algorithm. The results indicate that public expenditure and trade openness can enhance the BRICS countries' economic growth, with the positive impact probability of 75.69% and 67.11%, respectively. Also, FDI, inflation, and tax revenue positively affect this growth, though the probability of positive effect is ambiguous, ranging from 51.13% to 56.36%. Further, the research's major finding is that shadow economy and control of corruption have a positive effect on the economic growth of the BRICS countries. Nevertheless, the posterior probabilities of these two factors are 62.23% and 65.25%, respectively. This result suggests that their positive effect probability is not high.

The Impact of Foreign Ownership on Capital Structure: Empirical Evidence from Listed Firms in Vietnam

  • NGUYEN, Van Diep;DUONG, Quynh Nga
    • The Journal of Asian Finance, Economics and Business
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    • v.9 no.2
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    • pp.363-370
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    • 2022
  • The study aims to probe the impact of foreign ownership on Vietnamese listed firms' capital structure. This study employs panel data of 288 non-financial firms listed on the Ho Chi Minh City stock exchange (HOSE) and Ha Noi stock exchange (HNX) in 2015-2019. In this research, we applied a Bayesian linear regression method to provide probabilistic explanations of the model uncertainty and effect of foreign ownership on the capital structure of non-financial listed enterprises in Vietnam. The findings of experimental analysis by Bayesian linear regression method through Markov chain Monte Carlo (MCMC) technique combined with Gibbs sampler suggest that foreign ownership has substantial adverse effects on the firms' capital structure. Our findings also indicate that a firm's size, age, and growth opportunities all have a strong positive and significant effect on its debt ratio. We found that the firms' profitability, tangible assets, and liquidity negatively and strongly affect firms' capital structure. Meanwhile, there is a low negative impact of dividends and inflation on the debt ratio. This research has ramifications for business managers since it improves a company's financial resources by developing a strong capital structure and considering foreign investment as a source of funding.

Open-Cell Rigid Polyurethane Foam Using Reactive Cell Opening Agents (반응성 기포개방제를 이용한 개방기포형 경질우레탄폼)

  • Ahn, WonSool
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.14 no.5
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    • pp.2524-2528
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    • 2013
  • Cell opening characteristics dependent on the cell openers for the conventional formulation of a closed-cell polyurethane foam (PUF) was studied using 1-butanol and lithium salt of 12-hydroxystearic acid (Li-12HSA) as the reactive cell opening agents. While cell openining content of only 10.5 % was obtained for the sample with 4 phr of 1-butanol as the single reactive cell opener, that of 98.0% could be obtained for the sample with 2 phr of Li-12HSA as the reactive co-cell opener. As the results, it showed that a fully open-cell rigid PUF could be obtained by introducing a novel reactive cell opener, having a functional group able to form a bulky side-chain on the urethane networks, without severe loss of mechanical properties of the closed-cell PUF like cell size, bulk density, and thermal conductivity.

Vertical Integration and Production System Analysis of Korean Popular Music Industry in Creative Economy Era 2000-2013 (창조경제시대의 한국대중음악산업 수직계열화와 생산시스템 분석 2000-2013)

  • Kim, Ki-Deog;Choe, Sok-Ho
    • The Journal of the Korea Contents Association
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    • v.14 no.6
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    • pp.44-53
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    • 2014
  • This study seeks to analyze vertical integration structure of Korean popular music market focused on corporation concentration and production system by applying production of culture perspective of Peterson, Subject of analysis is Melon weekly music chart(2000-2013), which is No.1 digital music distributor. The result showed vertical integration structure of Korean popular music industry was different from America. Vertical integration of American major was based on open system to be responsible for promotion and distribution by M&A of independent label but entrusted them-with total production to cope-with uncertainty of music market. On the other hand, Korean system was in charge of pure distribution only as digital service provider and it showed modified vertical structure because traditional value chain was destroyed by changing digital music environment. Especially found seriousness of oligopoly by distribution company of conglomerate affiliation. and this is harm against building healthy industry ecosystem in creative economy era and it needs improvement through study of advanced case, open system.

Determination of Growth Hormone cDNA in Brook Trout, Salvelinus fontinalis (Brook trout (Salvelinus fontinalis) 성장호르몬 cDNA의 염기배열 결정)

  • 이종영;권혁추;김세연;박홍양
    • Journal of Aquaculture
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    • v.11 no.3
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    • pp.327-335
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    • 1998
  • Amplification of brook trout growth hormone cDNA using polymerase chain reactiono (PCR) produced a nucleotide of 1,120 bp which contained the 5'non-coding region (13bp), an open reading frame (ORF) coding a growth hormone polypeptide consisting of 210 amino acids (630 bp), and a 3'non-coding region (477 bp). In open reading frame s signal peptide of 22 amino acid and 2 potential disulfide bond sites deduced by 4 cysteine residues were obser-bed. Brook trout growth hormone has 97.1%, 94.8%, 94.3%, 91.9%, 66.2%, 63.5%, 62.9%, 62.3%, 53.8% and 48.1% amino acid identity with that of Atlantic salmon, chum salmon, rainbow trout, coho salmon, tuna, tilapia, yellow tail, carp, flounder and eel, respectively.

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