• Title/Summary/Keyword: quantitative test

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Effect of Si Addition on the Corrosion Resistance of Diamond-Like Carbon (DLC) Films

  • Kim, Woo-Jung;Kim, Jung-Gu;Park, Se-Jun;Lee, Kwang-Ryeol
    • Corrosion Science and Technology
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    • v.4 no.6
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    • pp.226-230
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    • 2005
  • Si incorporated diamond-like carbon (Si-DLC) films ranging from 0 to 2 at.% contents were deposited on STS 316L substrates for orthopedic implants by means of r.f. plasma-assisted chemical vapor deposition (r.f. PACVD) technique, using mixtures of benzene ($C_6H_6$) and silane ($SiH_4$) as the precursor gases. This study provides the reliable and quantitative data for assessment of the effect of Si incorporation on corrosion property in the simulated body fluid environment through the electrochemical test. It was found that corrosion to resistance of Si-DLC coatings with increasing Si content are improved owing to high $sp^3$ bonding.

Experimental Study on CO2 Diffusivity in Cementitious Materials

  • Jung, Sang-Hwa;Lee, Myung-Kue;Kim, Jee-Sang
    • Corrosion Science and Technology
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    • v.4 no.2
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    • pp.69-74
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    • 2005
  • The carbonation of concrete is one of the major factors that cause durability problems in concrete structures. The rate of carbonation depends largely upon the diffusivity of carbon dioxide in concrete. The purpose of this study is to identify the diffusion coefficients of carbon dioxide for various concrete mixtures. To this end, several series of tests have been planned and conducted. The test results indicate that the diffusion coefficient increases with the increase of water-cement ratio. The diffusion coefficient decreases with the increase of relative humidity at the same water-cement ratio. The diffusion of carbon dioxide reached the steady state within about five hours after exposure. The content of aggregates also influences the diffusivity of carbon dioxide in concrete. It was found that the diffusion coefficient of cement paste is larger then that of concrete or mortar. The quantitative values of diffusivity of carbon dioxide in this study will allow more realistic assessment of carbonation depth in concrete structures.

Quantitative analysis of effect of shrink fit in cold forging (냉간단조에서 금형 열박음 영향의 정량적 분석)

  • Li, Q.S.;Lee, M.C.;Jung, D.C.;Son, Y.H.;Joun, M.S.
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 2009.10a
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    • pp.119-123
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    • 2009
  • In this paper, effects of major design parameters of cold forging dies on die mechanics are quantitatively investigated with emphasis on shrink fit using a thermoelastic finite element method. A ball-stud cold forging process found in a cold forging company is selected as a test process and the effects of die insert material, shrink fit, dimension of ring, partition of die inert and clamping force on effective stress and circumferential stress are analyzed.

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The Moderating Effect of Operations Efficiency on the Links between Environmental Performance and Financial Performance: The UK Evidence

  • Ramanathan, Ramakrishnan;Akanni, Adewole Oluwatomi
    • Asian Journal of Innovation and Policy
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    • v.4 no.1
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    • pp.76-102
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    • 2015
  • Drawing upon the resource-based-view of a firm, we investigate the moderating role of operations efficiency on the link between environmental and financial performance. Extant literature has highlighted that operations efficiency is closely associated with the environmental/financial performance of firms, but no empirical study has investigated how operations efficiency affects the link between environmental and financial performance. We argue that operations efficiency could act as a moderator of this relationship. To test the hypothesized relationships, we have used available secondary quantitative UK data, namely data on the environmental/financial performance of Britain's most admired companies. By employing moderated regression analysis, we have found strong evidence for the moderating impact of operations efficiency. Our results are useful to managers in that they show that improvements in operations efficiency in a company can also help improve environmental/financial performance and vice versa.

A Study on the Level of Health Beliefs and Knowledge about Human Papilloma Virus(HPV) Vaccination among Health College Students (보건 계열 대학생의 인유두종바이러스 예방접종 관련 건강신념과 지식정도)

  • Eo, Yong-Sook;Lee, Nae-Young;Kim, Ji-Soo
    • Journal of Fisheries and Marine Sciences Education
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    • v.26 no.2
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    • pp.345-356
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    • 2014
  • The purpose of this study was to identify the knowledge level of human papilloma virus and performance of anti-cervical cancer vaccine among health college student in Korea. A quantitative, descriptive design was used to study 471 students in Ulsan, recruited from April 1 to May 30, 2011. The data were analyzed SPSS program, using descriptive statistics, t-test and ANOVA. The percentage of the participants who received HPV vaccination was 4.0%. The average level of health belief and knowledge about human papilloma virus were 3.05, 5.01 points. Therefore, it is needed to reduce HPV infection through concrete educational programs and advertisement. Also, this educational programs need to include strategies the knowledge of human papilloma virus.

An ESL Program in Higher Education: Is An ESL Program Only Enough to Develop ESL Learners' CALP?

  • Yun, Jee-Hwan;Park, Yong-Hyo;Song, Jihyun
    • English Language & Literature Teaching
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    • v.17 no.3
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    • pp.291-307
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    • 2011
  • The primary purpose of this study was to report overall findings of academic English proficiency of university ESL students in an ESL program from 2003 to 2008 at a university in the U.S. Furthermore, this study proposes to explore the effectiveness of the ESL program on developing the ESL learners' academic English proficiency. In order to achieve these purposes, this study applied a quantitative research methodology which analyzed data (more than 3,000 samples) collected by the university ESL program. The data included the ESL learners' English proficiency test scores. The results indicated that the effectiveness of the ESL program was significant in improving the ESL learners' cognitive/academic language proficiency across all three groups: ESL-only, ESL + Under, and ESL + Grad. That is, after either a complete ESL program intervention only or both a partial ESL program intervention and taking academic courses, the three groups' academic English proficiency was increased to almost same degree The findings are discussed and implications for pedagogy are suggested.

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Decision-tree Model of Treatment-seeking Behaviors after Detecting Symptoms by Korean Stroke Patients

  • Oh Hyo-Sook;Park Hyeoun-Ae
    • Journal of Korean Academy of Nursing
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    • v.36 no.4
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    • pp.662-670
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    • 2006
  • Purpose. This study was performed to develop and test a decision-tree model of treatment-seeking behaviors about when Korean patients visit a doctor after experiencing stroke symptoms. Methods. The study used methodological triangulation. The model was developed based on qualitative data collected from in-depth interviews with 18 stroke patients. The model was tested using quantitative data collected from interviews and a structured questionnaire involving 150 stroke patients. The predictability of the decision-tree model was quantified as the proportion of participants who followed the pathway predicted by the model. Results. Decision outcomes of the model were categorized into immediate and delayed treatment-seeking behavior. The model was influenced by lowered consciousness, social-group influences, perceived seriousness of symptoms, past history of hypertension or stroke, and barriers to hospital visits. The predictability of the model was found to be 90.7%. Conclusions. The results from this study can help healthcare personnel understand the education needs of stroke patients regarding treatment-seeking behaviors, and hence aid in the development of educational strategies for stroke patients.

Defective Surface Analysis of Aluminum Bonding Pads for Au Wire Bonding

  • Son, Dong-Ju;Ji, Yong-Joo;Jeon, Yoon-Su;Soh, Dae-Wha;Hong, Sang-Jeen
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2009.11a
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    • pp.4-4
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    • 2009
  • Surface analysis on defective wire-bonding pads are performed in flash memory assembly. Week wire bonding may cause a significant effect on the final product reliability, and the surface condition of the aluminum bond pads is critical in terms of product reliability. To find out possible week bonding on semiconductor interconnects, ball sheer test (BST) has been performed. On some defective or week bonded pads, we have investigated the surface contents, assuming that the week bonding is induced from the surface conditions. AES and XPS are employed for the quantitative surface analysis on defective dies.

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Best Combination of Binarization Methods for License Plate Character Segmentation

  • Yoon, Youngwoo;Ban, Kyu-Dae;Yoon, Hosub;Lee, Jaeyeon;Kim, Jaehong
    • ETRI Journal
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    • v.35 no.3
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    • pp.491-500
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    • 2013
  • A connected component analysis from a binary image is a popular character segmentation method but occasionally fails to segment the characters owing to image noise and uneven illumination. A multimethod binarization scheme that incorporates two or more binary images is a novel solution, but selection of binarization methods has never been analyzed before. This paper reveals the best combination of binarization methods and parameters and presents an in-depth analysis of the multimethod binarization scheme for better character segmentation. We carry out an extensive quantitative evaluation, which shows a significant improvement over conventional single-method binarization methods. Experiment results of six binarization methods and their combinations with different test images are presented.

A Quantitative Ultrasound Tomography Algorithm Via the Second Order Approximation of the Model Equation (모델식의 2차 근사에 의한 정량적인 초음파 단층 촬영 알고리즘)

  • 김환우;김영길
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.29B no.11
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    • pp.16-21
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    • 1992
  • The validity of the application of the second-order Born equation to the ultrasound tomography algorithm is studied by comparing the scattered fields computed using the first-order Born equation, the first-order Rytove equation, and the second-order Born equation. The second-order Born equation turns out to provide more desirable results than the other two equations for a certain group of test objects. Phantom images with resolutions upto 1 pixel$\times$1 pixel are satisfactorily reconstructed using the second-order Born equation. It is shown that when the view angle is limited, good resonstruction results are also obtained using multi-frequency incident fields.

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