• 제목/요약/키워드: material factors

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비균질 구배기능 계면영역을 고려한 적층 만무한체의 동일선상 복수균열 해석 (The Problem of Collinear Cracks in a Layered Half-Plane with a Functionally Graded Nonhomogeneous Interfacial Zone)

  • 진태은;최형집;이강용
    • 대한기계학회논문집A
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    • 제20권4호
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    • pp.1275-1289
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    • 1996
  • The plane elasticity problem of collinear cracks in a layered medium is investigated. The medium is modeled as bonded structure constituted from a surface layer and a semi-infinite substrate. Along the bond line between the two dissimilar homegeneous constituents, it is assumed that as interfacial zone having the functionally graded, nonhomogeneous elastic modulus exists. The layered medium contains three collinear cracks, one in each constituent material oriented perpendicular to the nominal interfaces. The stiffness matrix formulation is utilized and a set of homogeneous conditions relevant to the given problem is readily satisfied. The proposed mixed boundary value problem is then represented in the form of a system of integral equations with Cauchy-type singular kernels. The stress intensity factors are defined from the crack-tip stress fields possessing the standard square-root singular behavior. The resulting values of stress intensity factors mainly address the interactions among the cracks for various crack sizes and material combinations.

Characteristics of Warm Acupuncture Reported in Experimental Studies: A Descriptive Narrative Review

  • Choi, Ji Won;Choi, Seo Young;Lee, Ji Sun;Yang, Gi Young
    • Journal of Acupuncture Research
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    • 제36권3호
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    • pp.131-139
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    • 2019
  • Background: This study aimed to investigate the correlation between heat transmission and intervention factors for warm acupuncture (such as features of acupuncture material and moxa, the treatment method, and clinical symptoms). Methods: Korean, English, Chinese and Japanese databases were analysed. Experimental studies that explored the association between thermal stimulation delivery and warm acupuncture intervention factors were included. The peak temperature, time to reach the peak temperature, and time of the effective stimulus, were set as the major parameters and analysed. Results: A total of 12 studies were included. Two studies were associated with the acupuncture needle material, 4 studies associated with the moxa mass, 1 study associated with the moxa density, 2 studies associated with the location of ignition, and 1 study associated with treatment environment were reviewed. The reporting quality of the 12 studies was low. Conclusion: This study provided limited information because of the heterogeneity of materials and parameters depending on each experiment. Further studies should clarify the correlation between heat transmission and intervention factors for warm acupuncture.

다구찌 방법에 기초한 선삭에서 진원도에 영향을 미치는 인자에 관한 평가 (An Evaluation of Factors on the Influence Roundness in Turning Based on the Taguchi Method)

  • 강신길;이창호;장성민
    • 한국생산제조학회지
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    • 제20권4호
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    • pp.495-501
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    • 2011
  • The purpose of this study is to improve the roundness of CNC turning so that helps the operator to choose the right turning conditions to produce a product with the given parameters. This paper focuses on determining the optimal levels of machining factors for circular shaft with CNC turning. For this purpose, the optimization of factors is performed based on experimental design method. A design and analysis of experiments are conducted to study the effects of these factors on the roundness by using the SIN ratio, analysis of ANOVA, and F-test. Factors, namely, fixed pressure, wall thickness, depth of cut, and feed rate are optimized with consideration of the roundness. The boring tool used in this study is a tungsten carbide coated. The material of workpiece is Al6061 and the machining method is dry cutting.

Study of Factors of Relationship Marketing at DIY Woodworking Workshop

  • Chun, Tong Whan;Kim, Kwang-Roul
    • 한국가구학회지
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    • 제20권6호
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    • pp.552-559
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    • 2009
  • While the population conducting the production-oriented leisure activity is spread, the expertly franchised types of woodworking workshop based on good organization and economic power are also undergoing rapid growth with the related industries. Such tendency needs the systemized marketing strategy for woodworking workshop industry, but most of the woodworking workshops are regarding the deal with customers as simple exchange business in the market. The factors of the relationship marketing hereupon should be constituted as basic material for the study of the relationship marketing of DIY woodworking workshop. This study was intended to select the appropriate factors for relationship marketing and to apply the related theoretical backgrounds on the basis of the preceding studies regarding the factors of relationship marketing. As the factors it was selected that service and expertise of staff under the category of the characteristics of staff, reasonable price, diversity of products and convenience of facility in woodworking workshop under the category of the customer-oriented service, and communication and favorite program under that of the relation-oriented service.

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소나 음향창의 설계 인자가 난류 유동 유기 자체 소음의 전달 함수에 미치는 영향 해석 (The Influence of Design Factors of Sonar Acoustic Window on Transfer Function of Self Noise due to Turbulent Boundary Layer)

  • 신구균;서영수;강명환;전재진
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2012년도 추계학술대회 논문집
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    • pp.568-574
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    • 2012
  • Turbulent boundary layer noise is already a significant contributor to sonar self noise. For developing acoustic window of sonar system to reduce self noise, a parametric study of design factors of acoustic window is presented. Distance of sensor array from acoustic window, material and damping layer are studied as design factors to influence in the characteristics of the transfer function of self noise. As the result these design factors make change the characteristics of transfer function slightly. Among design factors the location of sensor array is most important parameter in the self noise reduction.

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패션제품 강박구매행동에 영향을 미치는 심리적 변인 연구 (Psychological Factors affecting Compulsive Buying Behavior on Fashion Products)

  • 이승희;신초영
    • 한국의류학회지
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    • 제28권5호
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    • pp.658-667
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    • 2004
  • The purpose of this study was to examine factors affecting compulsive buying behavior purchasing behavior. Four hundred female college students who have purchased fashion products via Internet shopping or TV home shopping were surveyed. For data analysis, descriptive statistics, factor analysis, t-test, and multiple regression analysis were used. As the results, 16.3% of respondents were revealed as compulsive buyers. For materialism instrument, four factors of materialism were found and labeled as 'material'. 'consumption', 'happiness', and 'economic value' factors. Also, two factors of entertainment pursuit were also identified as 'change' and 'adventure' pursuit. There were statistically significant differences between compulsive buyers and non-compulsive buyers in terms of materialism, success, and change pursuit, self-esteem, compensation, impulsive purchasing, and binge eating. Compulsive consumption scores were correlated to higher materialism, compensatory, impulsive purchasing, binge eating, shifting, entertainment pursuit, and lower self-esteem. Also, results of multiple regression revealed that compensatory, binge eating, and happiness pursuit were significantly to related to compulsive buying.

Development of a Scaling Factor Prediction Method for Radioactive Composition in Low-level Radioactive Waste

  • Park, Jin-Beak;Lee, Kun-Jai
    • 한국원자력학회:학술대회논문집
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    • 한국원자력학회 1995년도 춘계학술발표회논문집(2)
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    • pp.833-838
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    • 1995
  • This study presents a method to predict plant-specific and operational history dependent scaling factors. Realistic and detailed approaches are taken to find scaling factors at reactor coolant. This approach begins with fission product release mechanisms and fundamental release properties of fuel-source nuclide such as fission product and transuranic nuclide. Scaling factors at various waste streams are derived from the predicted reactor coolant scaling factors with the use of radionuclide retention and build up model. This model makes use of radioactive material balance within the radioactive waste processing systems. According to input parameters of plant operation history, scaling factors predicted at reactor coolant and waste streams are well brought out the effects of plant operation history.

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분기좌굴이론의 탄소성 유한요소법에의 적용 (An Introduction of Bifurcation Algorithm into the Elastic-Plastic Finite Element Analysis)

  • 김종봉;양동열;윤정환
    • 소성∙가공
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    • 제9권2호
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    • pp.128-139
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    • 2000
  • Wrinkling is one of the major defects in sheet metal products and may be also attributable to the wear of the tool. The initiation and growth of wrinkles are influenced by many factors such as stress state, mechanical properties of the sheet material, geometry of the body, and contact condition. It is difficult to analyze the wrinkling initiation and growth considering the factors because the effects of the factors are very complex and the wrinkling behavior may show a wide variation for small deviations of the factors. In this study, the bifurcation theory is introduced for the finite element analysis of wrinkling initiation and growth. All the above mentioned factors are conveniently considered by the finite element method. The finite element formulation is based on the incremental deformation theory and elastic-plastic elements considering the planar anisotropy of the sheet metal. The proposed method is verified by employing a column buckling problem. And then, the initiation and growth of wrinkling in deep drawing of cylindrical cup are analyzed.

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