• Title/Summary/Keyword: four point problems

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NUMERICAL METHOD FOR SINGULAR PERTURBATION PROBLEMS ARISING IN CHEMICAL REACTOR THEORY

  • Andargie, Awoke
    • Journal of applied mathematics & informatics
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    • v.28 no.1_2
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    • pp.411-423
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    • 2010
  • In this paper, a numerical method for singular perturbation problems arising in chemical reactor theory for general singularly perturbed two point boundary value problems with boundary layer at one end(left or right) of the underlying interval is presented. The original second order differential equation is replaced by an approximate first order differential equation with a small deviating argument. By using the trapezoidal formula we obtain a three term recurrence relation, which is solved using Thomas Algorithm. To demonstrate the applicability of the method, we have solved four linear (two left and two right end boundary layer) and one nonlinear problems. From the results, it is observed that the present method approximates the exact or the asymptotic expansion solution very well.

NUMERICAL INTEGRATION METHOD FOR SINGULAR PERTURBATION PROBLEMS WITH MIXED BOUNDARY CONDITIONS

  • Andargie, Awoke;Reddy, Y.N.
    • Journal of applied mathematics & informatics
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    • v.26 no.5_6
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    • pp.1273-1287
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    • 2008
  • In this paper, the numerical integration method for general singularly perturbed two point boundary value problems with mixed boundary conditions of both left and right end boundary layer is presented. The original second order differential equation is replaced by an approximate first order differential equation with a small deviating argument. By using the trapezoidal formula we obtain a three term recurrence relation, which is solved using Thomas Algorithm. To demonstrate the applicability of the method, we have solved four linear (two left and two right end boundary layer) and one nonlinear problems. From the results, it is observed that the present method approximates the exact or the asymptotic expansion solution very well.

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A Study on the State of Affairs of Green Fashion Marketing (그린 패션 마케팅 현황에 관한 연구)

  • Park, Song-Ae
    • Journal of the Korea Fashion and Costume Design Association
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    • v.13 no.2
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    • pp.121-131
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    • 2011
  • Green Marketing, a response to the serious environment problems of the 21st century, is an important point for trends in both art and fashion. It is a strategy for reminding consumers of the threatening environment problems and to recognize that everyone must take responsibility for these problems. Green marketing is a concept that is the point at issue and social reform movement. The purpose of this study was to find examples of Green Marketing in fashion and classify them into four groups. The results of this study were as follows. First, the terms related to green marketing as related to fashion can be categorized into four areas: 1. Eco-friendly product marketing: product merchandising that usually uses organic materials and green manufacturing processes. 2. Green-communication marketing: PR strategies that use green slogans through deep impression advertising or special promotional events relating reducing, reusing and recycling, etc., with the brand's name. 3. Green environmental-marketing: marketing strategies that is an enlightenment campaign for environmental preservation and sustainable fashion design such as reusing, recycling, and reducing. 4. Cause-related marketing: marketing plans that return profits to society and that take an active part in the causes of the community. It was expected that these types of green marketing strategies would yield positive effects in enhancing brand value and consumer confidence as well as increasing profits.

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Analytical solutions to magneto-electro-elastic beams

  • Jiang, Aimin;Ding, Haojiang
    • Structural Engineering and Mechanics
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    • v.18 no.2
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    • pp.195-209
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    • 2004
  • By means of the two-dimensional basic equations of transversely isotropic magneto-electro-elastic media and the strict differential operator theorem, the general solution in the case of distinct eigenvalues is derived, in which all mechanical, electric and magnetic quantities are expressed in four harmonic displacement functions. Based on this general solution in the case of distinct eigenvalues, a series of problems is solved by the trial-and-error method, including magneto-electro-elastic rectangular beam under uniform tension, electric displacement and magnetic induction, pure shearing and pure bending, cantilever beam with point force, point charge or point current at free end, and cantilever beam subjected to uniformly distributed loads. Analytical solutions to various problems are obtained.

Validation of Critical Care Non-verbal Pain Scale for Critically Ill Patients (중환자 통증사정 도구의 타당성 평가)

  • Choi, Eun Hee;Kim, Jin Hee;Ko, Mi Suk;Kim, Ji Yang;Kwon, Eun Ok;Jang, In Sun
    • Journal of Korean Clinical Nursing Research
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    • v.19 no.2
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    • pp.245-254
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    • 2013
  • Purpose: This study was done to examine predictive validity of Critical Care Non-verbal Pain Scale (CNPS) and develop criteria for pain assessment using CNPS with critically ill patients who have communication problems. Methods: Data were collected from intensive care units at three major general hospitals in Seoul and Kyunggi province. During each observation, a nurse assessed pain severity using CNPS ratings (range 0-9) at four treatment stages: at rest, during central catheter dressing change (nonpainful procedure), position change and suctioning (routine painful procedures). Patients also assessed their pain using a self-report 4-point VRS-4. Results: There were significant differences between the four treatment stages except between "at rest" and "nonpainful procedure". Strong correlations were found between CNPS and VRS-4 for "at rest" (r=.552, p<.001), central catheter dressing change (r=.505, p<.001), position change (r=.709, p<.001), and suctioning (r=.662, p<.001). ROC curve analysis of CNPS based on 3 point on VRS-4 showed the cutoff point was 3 for CNPS, the starting point for pain management with 73% sensitivity, 92.2% specificity, 73% positive predictive value, and 92.8% negative predictive value. Conclusion: Results indicate that CNPS is a valid tool for measuring pain in critically ill patients with communication problems and 3 point should be the standardized pain treatment point.

Isogeometric analysis of gradient-enhanced damaged plasticity model for concrete

  • Xu, Jun;Yuan, Shuai;Chen, Weizhen
    • Computers and Concrete
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    • v.23 no.3
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    • pp.171-188
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    • 2019
  • This study proposed a new and efficient 2D damage-plasticity model within the framework of Isogeometric analysis (IGA) for the geometrically nonlinear damage analysis of concrete. Since concrete exhibits complicated material properties, two internal variables are introduced to measure the hardening/softening behavior of concrete in tension and compression, and an implicit gradient-enhanced formulation is adopted to restore the well-posedness of the boundary value problem. The numerical results calculated by the model is compared with the experimental data of three benchmark problems of plain concrete (three-point and four-point bending single-notched beams and four-point bending double-notched beam) to illustrate the geometrical flexibility, accuracy, and robustness of the proposed approach. In addition, the influence of the characteristic length on the numerical results of each problem is investigated.

Problems of Internet-based Distance Learning (인터넷 원격교육의 문제점에 관한 조사연구)

  • Nam Sang-Zo
    • Proceedings of the Korea Contents Association Conference
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    • 2005.11a
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    • pp.284-288
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    • 2005
  • Internet-based distance learning is proliferated, but justifying its educational effectiveness is challenging. Investigation into the problems is important and fundamental for the study on the educational effectiveness. In this study, problems of Internet-based distance learning are structured by four categories as environmental problems, student problems, course design problems and operational problems. Based on a survey of distance education participants, problems are analysed. Also, analysis from the point of demographic differences such as sex, job existence and age is performed.

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1. Four legs Cock ; -Some problems of modern biological education in Japan

  • Haruo Takada, D.Se
    • The Korean Journal of Zoology
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    • v.23 no.2
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    • pp.109-114
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    • 1980
  • A professor of biology, whose name is Dr. Mikamo, National Asahigawa Medical School, recently made an appallingly interesting report to the Hokkaido Meeting, the Zoological Society of Japan at last summer which was to the effect: "Students were asked to draw pictures of a cock and a fly at an examination in biology they took at few medical and dental schools of our national universities. Less than ten percent of the drawings were in a passable likeness of the creatures in question; the rest being nothing more than indefinite and vague, often to the point of primitive. Some cocks were even bestowed with four beautiful legs".egs".uot;.

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Observation on the shape of the neck -by principal component analysis of the mesurements- (피복 구성을 위한 경부 형태의 관찰)

  • 이연순
    • Journal of the Ergonomics Society of Korea
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    • v.10 no.2
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    • pp.31-42
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    • 1991
  • To understand the shape of the neck in a view of garment planning, principal component analysis has been appliedto the measurement of the neck. The neck surface development and the cross sections of the neck have been observed. The materials consist of the body mearsurements, the neck surface developments and the cross sec- tions of the necks of a total of 108 korean woman students. The difference between the right side and the left side of the neck has not been reconginiged. But the differenece among the height of the front neck point, that of the side neck point and that of the back neck point has been recognized. 2. The initial 41 items have been found having variety and duplication. So two criteria have been made to solve those problems and the selection of 34 items have been made by each criterion. 3. 43 and 34 items have been compared by means of accumulative ratios of contribution and of clearness within the meaning of principal component. As a result, 34 measurement items have been further anylysis. 4. As a result of principal component analysis on the 34 items, the four principal components have been found obtaines and inter-preted. The four principal components are 1) the thick of the neck, 2) the front neck-line on the waist basic pattern, basic pattern, 3) the shape of the neck surface development, and 4) the back neck-line on the waist basic pattern. 5. According to the graphic informations concerning these principal components, the meaning of these four principal components has been grasped on the visual. As a result, there is a large individual difference in the shape of neck.

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