• Title/Summary/Keyword: degree distribution

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A Study on the Macro-Scopic Spray Characteristic of Homogeneous Degree for the GDI Injector According to Mixture(Gasoline-Diesel) Ratio Using Mie-Scattering Method and the Entropy Analysis (Mie 산란 방법과 엔트로피 해석 방법을 이용한 혼합연료비에 따른 분무 균질도 특성에 관한 연구)

  • Lee, Chang-Hee;Lee, Ki-Hyung;Lee, Chang-Sik;;Bae, Jae-Il
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.27 no.1
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    • pp.69-75
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    • 2003
  • In this study, his technique was applied to a GDI spray in order to investigate the mixture distribution. In addition, the homogeneity degree and diffusion effect according to ambient temperature in the high pressure chamber were analyzed by using an entropy analysis method. From this experiment, we could find that entropy analysis is very effective method for the analysis of mixture formation, and the entropy values increase with the progress of uniformity in diffusion Process. we tried to provide the fundamental data for parameter which effects on the spray macroscopic characteristics with mixture ratio of diesel and gasoline. In addition, the mixture formation was analyzed by using entropy analysis. The entropy analysis is based on the concept of statistical entropy, and it identifies the degree of homogeneity in the fuel concentration. From the entropy analysis results we could find that the direct diffusion phenomena is a dominant factor in the formation of a homogeneous mixture at downstream of GDI spray especially in vaporizing conditions. As to increasing ambient temperature and increasing gasoline rate, the entropy intensity using the statistic thermodynamics method is increased because evaporation rate is higher gasoline than diesel.

The Effect of Fluid Flow on the Primary Particle of Al-7wt%Si Alloy in Electromagnetic Stirring (전자교반시 Al-7wt%Si합금의 초정입자에 미치는 유동의 영향)

  • Lim, Sung-Chul;Yoon, Eui-Pak
    • Journal of Korea Foundry Society
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    • v.16 no.6
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    • pp.565-575
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    • 1996
  • In this study, to gain the semi-solid alloy we employed the electromagnetic rotation by a induction motor of 3-phases and 2-poles for Al-7wt%Si alloy and observed the size of primary solid particle, distribution state of primary solid particle, the degree of sphericity, and fraction of primary solid for the evaluation of its results. The size of primary solid particle increases from $98{\mu}m$ to $118{\mu}m$ as solid fraction increases from 0.2 to 0.5. The degree of sphericity increased as the solid fraction increased. Solid particles obtained from the microstructures of isothermally held sample were coarsened and the degree of sphericity was enhanced as isothermal holding time increased. However, when the sample was stirred for more than 40min, solid particles merged together and liquid phase was entrapped within the cluster of solid particles. The size of primary solid particle was not changed significantly with the variation of input voltages by 160V over which solid particles began to merge together to be a large cluster of about $170{\mu}m$ at 180V. The standard deviation and the degree of sphericity were not changed significantly with the variation of input voltage.

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Determinants of Voluntary Audit of Small and Medium Sized Enterprises: Evidence from Vietnam

  • HA, Hanh Hong;NGUYEN, Anh Huu
    • The Journal of Asian Finance, Economics and Business
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    • v.7 no.5
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    • pp.41-50
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    • 2020
  • The paper investigates the factors that affect the demand for a voluntary audit of small and medium-sized enterprises (SMEs) in Vietnam. A structured questionnaire survey of 284 SMEs was employed, preceded by in-depth interviews with auditors and SMEs' managers. The research used logistic regression estimator to address econometric issues and to improve the accuracy of the regression coefficients. The results show that the degree of director's view on voluntary audit, related stakeholder, degree of recommendation, and firm size have a statistically significant positive effect on audit decisions of SMEs while degree of audit fee has a statistically significant negative effect, and degree of subjective norm does not affect. This indicated that SMEs are more likely to have an external audit if they have some typical features: it is becoming larger in terms of size, and the directors consider that the audit has a relative benefit outweighing its cost. The research results suggested that Vietnam Government should make a statutory audit of SMEs' financial statements rather than make it an option for SMEs. The auditing firms were also recommended to actively take their audit services to SMEs rather than waiting for the SMEs' managers to contact them for their services.

Determination of Whiteness Condition for Efficient Milling in Rice Processing Complex (RPC에서 효율적인 도정을 위한 백도조건 결정)

  • Kim O. W.;Kim H.;Kim D. C.;Kim S. S.
    • Journal of Biosystems Engineering
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    • v.30 no.4 s.111
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    • pp.242-248
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    • 2005
  • There was no useful milling standard to produce high quality milled rice efficiently and adequately in Rice Processing Complex. Therefore, the whiteness of milled rice produced Rice Processing Complexes were different according to Rice Processing Complexes and milling periods at the same Rice Processing Complex. This research was carried out to contribute the production and distribution of high quality milled rice through determination of whiteness condition of milled rice as a milling stndard based on degree of bran removal using New $May-Gr\ddot{u}wald$ reagent dyeing method and taste of cooked rice. The optimum whiteness value of milled rice for efficient milling in Rice Processing Complex was found to be from 40 to 41, while the degree of milling was from $8.9\%\;to\;9.2\%.$ At this whiteness condition, the first derivative of whiteness value according to degree of milling was higher than the average value from brown rice to well milled rice, and the broken kernel ratio was from $3.0\%\;to\;3.4\%.$ This whiteness condition ($40\~41$) could be considered as a milling condition in Rice Processing Complex.

A Study on the Predicting Transverse Residual Stress at the Ultra Thick FCA Butt Weldment of Hatch Coaming in a Large Container Vessel (대형 컨테이너선의 해치 코밍 FCA 맞대기 용접부의 횡 방향 잔류응력 예측에 관한 연구)

  • Shin, Sang-Beom;Lee, Dong-Ju;Lee, Joo-Sung
    • Journal of Welding and Joining
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    • v.28 no.4
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    • pp.33-40
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    • 2010
  • The purpose of this study is to establish a predictive equation of transverse residual stress at the thick FCA butt weldment of large container vessel. The variables used were restraint degree, yield strength of base material, thickness of weldment and welding heat input. Restraint degree at the thick weldment of container ship having the various welding sequence was calculated using FEA. From the result, the H-type specimen was designed to reproduce the level of restraint degree at the actual weldment of containership. Based on the results, the predictive equations of the mean value and the distribution of transverse residual stress at each location of the weldment were established using dimensional analysis and multiple-regression method. The predictive equations were verified by comparing with those measured by XRD in the actual weldment of the ship.

Entrepreneurial Orientation, Network Competence and Human Capital: The Internationalization of SMEs in Oman

  • SANYAL, Shouvik;HISAM, Mohammed Wamique;BAAWAIN, Ali Mohsin Salim
    • The Journal of Asian Finance, Economics and Business
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    • v.7 no.8
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    • pp.473-483
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    • 2020
  • Internationalization of SMEs has gathered pace in recent times with falling trade barriers and rising world trade encouraging small firms to seek profits and growth in foreign markets. This has attracted the attention of researchers, and several studies have been conducted in Western nations on the factors influencing the process of SME internationalization. However, hardly any study has been done on SME internationalization in the Gulf Cooperative Council (GCC) region, thus leaving a gap in the literature. This study investigates the influence of four factors, namely, human capital, network competency, entrepreneurial orientation, and market volatility on the degree of internationalization of SMEs in Oman. The study employs survey data collected from 150 SME owners and managers using a structured questionnaire having 27 items, and has been analyzed using correlation and logistic regression, as the dependent variable is binary in nature. The results reveal the impact of the chosen variables on the degree of internationalization of SMEs. The findings of the study suggest that network competency has the highest impact on degree of internationalization of Omani SMEs, followed by human capital and entrepreneurial orientation, while market volatility, though insignificant, moderated the relationship between entrepreneurial orientation and degree of internationalization of Omani SMEs.

The S-Shaped Relationship Between Internationalization and Performance: Empirical Evidence from Laos

  • PHAN, Tu Anh;NGUYEN, Thuy Thi Kim;PHAN, Triet Minh
    • The Journal of Asian Finance, Economics and Business
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    • v.7 no.11
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    • pp.357-366
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    • 2020
  • The purpose of this study is to investigate the impact of internationalization on the business performance of firms in Laos as a transition economy. Using a panel dataset collected by the World Bank for 285 firms during the period 2009, 2012, and 2016 in the service and manufacturing industries, the two-steps Heckman regression results found robust evidence for the fact that the S-curve tie exists between the degree of internationalization and business performance of firms in Laos while controlling other factors. Specifically, if firms have a degree of internationalization lower than 0.4374, they will suffer losses due to the high cost of preparing for phase 1 which is market penetration. Then, when the degree of internationalization continues to increase from 0.4374 to 0.9131, firms will gain benefits from internationalization (phase 2), however, these benefits will deteriorate when the degree of internationalization is greater than 0.9131 (phase 3), meaning that firms will no longer be able to exploit economies of scale or advantages in target markets, or product cycles will fall into a state of decline. Interestingly, we also found that firms with a high concentration level of ownership and internationalization activities may achieve better performance than those with a low concentration of ownership and one which carried out internationalization activities.

Factors Affecting Consumer Goods Buyers' Choice in E-Commerce Sites: Evidence from Vietnam

  • PHAM, Hung Cuong
    • The Journal of Asian Finance, Economics and Business
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    • v.7 no.11
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    • pp.947-953
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    • 2020
  • The main purpose of this study is to find the factors affecting the consumer goods buyers' choice on e-commerce sites in Vietnam. By using the quantitative method, the paper examines the theoretical research model and tests four hypotheses. The sample was drawn from the population of e-commerce sites in Vietnam comprising about 1,000 respondents. This study used the questionnaire method to collect primary data to test the hypotheses. Data analysis of the questionnaire was done using SPSS. The results show that there is a correlation between personal preferences of consumers on colors and brands and their actual final choice on e-commerce sites in Vietnam. The most important factor affecting the consumer goods buyers' choice on e-commerce in Vietnam is the brand of E-commerce site, following by the color and position. Among all educational groups, respondents with a Master degree pay the biggest attention to the site's color attribute, and those with a Bachelor degree pay more attention to the brand attribute. Women pay much more attention to the location of the products on the screen than men, as do consumers with a PhD degree, over respondents with a Bachelor or Master degree, and foreigners over Vietnamese consumers.

Genetic Diversity and Speciation of Rana rugosa (Amphibia; Ranidae)

  • Yang, Suh-Yung;Min, Mi-Sook;Kim, Jong-Bum;Suh, Jae-Hwa;Kang, Young-Jin
    • Animal cells and systems
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    • v.4 no.1
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    • pp.23-30
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    • 2000
  • Horizontal starch gel electrophoresis for 29 populations (n=543) of the wrinkled frog, Rana rugosa, from Korea and Japan was peformed to assess the degree of genic variation and genetic diversity, and to understand the biogeographic pattern of distribution and speciation. A sum of 22 presumptive loci was screened from 17 enzymes and general proteins. Four loci, Aco, Est-3, Me-2, and Pgm, demonstrated high levels of polymorphism. The degree of average genetic variation of R. rugosa was P=22.7% (9.1-40.9%), Ho=0.086 (0.048-0.165) and He=0.090 (0.042-0.168). In the south-eastern region of the Korean peninsula (Chongsong, Yongchon, Ulsan, Kyongju, Pohang, yongdok and Ulchin), a few unique alleles in the Mpi locus were detected and their biogeographic implications were considered. The degree of genetic differentiation among the Korean populations was moderate (S=0.900), whereas the degree of genetic diversity between Korean and Japanese populations was notably high (S=0.687, D=0.293). This result corresponds with the data obtained by the mitochondrial cytochrome b gene sequence (Lee et al., 1999) suggesting that the Korean and Japanese R. rugosa might have evolved a specific level of genetic differentiation since their geographic isolation.

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Prediction of steel corrosion in magnesium cement concrete based on two dimensional Copula function

  • Feng, Qiong;Qiao, Hongxia;Wang, Penghui;Gong, Wei
    • Computers and Concrete
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    • v.21 no.2
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    • pp.181-187
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    • 2018
  • In order to solve the life prediction problem of damaged coating steel bar in magnesium cement concrete, this study tries to establish the marginal distribution function by using the corrosion current density as a single degradation factor. Representing the degree of steel corrosion, the corrosion current density were tested in electrochemical workstation. Then based on the Copula function, the joint distribution function of the damaged coating was established. Therefore, it is indicated that the corrosion current density of the bare steel and coated steel bar can be used as the boundary element to establish the marginal distribution function. By using the Frank-Copula function of Copula Archimedean function family, the joint distribution function of the damaged coating steel bar was successfully established. Finally, the life of the damaged coating steel bar has been lost in 7320d. As a new method for the corrosion of steel bar under the multi-dimensional factors, the two-dimensional Copula function has certain practical significance by putting forward some new ideas.