• Transactions of The Korea Fluid Power Systems Society
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• v.8 no.3
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• pp.21-26
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• 2011

Nonlinear seal friction in pneumatic cylinders can impede the performance of pneumatic systems designed for high precision positioning with favorable high speed actuation. The behaviour of an elastomeric piston seals in high speed pneumatic cylinders is analyzed by nonlinear finite element analysis using ABAQUS. The contact pressures, stress and strain distributions and frictional forces of the squeeze type piston seal are simulated with variation of the seal radial installed interference, the operating pressures, friction coefficients and piston rod velocities. The nonlinear finite element model of the squeeze type piston seal is used to predict deformation of a seal, friction force and contact pressure distributions.

• Journal of Welding and Joining
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• v.16 no.4
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• pp.47-54
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• 1998

Various equipments in plants are welded with two different materials and it is required to investigate the effects of fatigue crack propagation on the neighborhood of a welded portion. The characteristics of fatigue crack growth in the base metal of carbon and stainless steel, in the carbon and stainless steel sides located in the neighborhood of welded portion (carbon/stainless steel), respectively and welded portion, are investigated. The results show that the crack growth in the welded portion (carbon/stainless steel) is an average value of the crack growths in the carbon and stainless steel respectively located in the neighborhood of the welded portion. It is found that the crack growth in the welded portion is not significantly different from those in the carbon and stainless steel sides. Hence it can be concluded that the structure welded with two different materials wold not impede the integrity based on the fatigue crack growth.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.24 no.1
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• pp.99-106
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• 1979

The undehiscent ginseng seed did not germinate, even if the seeds were treated with GA_3, kinetin or IAA. Only GA_3 stimulated germination of dehiscent ginseng seed. The physiological roles of gibberellic acid on stimulation of the seed germination were enhancing production of soluble carbohydrate and sucrose. Then gibberellic acid stimulated biosynthesis of insoluble cellural materials and amino acids from sugars and incorporation of amino acids into protein. The fruit coat of ginseng seed did not impede water imbibition, but did function as water absorbor and reservoir.

• Korean Journal of Child Studies
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• v.21 no.4
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• pp.197-210
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• 2000

This integrative review of research on the role of toys in the pretend play of young children investigated claims about the relative effects of abstract or unrealistic compared with concrete or realistic toys. Researchers and educators acknowledge the benefits of pretend play as an expression of the child's capacity of symbolic functioning and they attend to strategies for promoting pretend play at each stage of its development, including the selection and presentation of playthings. Highly structured or realistic toys were once thought to impede pretend play because they can only be used for a single intended purpose whereas less structured toys are pliant and hold the child's interest over longer periods of time as new ideas are tried out. However, the present review suggests that realistic toys are effective for very young children who still have limited representational capacity, and that realistic toys continue to give impetus to make-believe even for kindergarten children.

• 유공압시스템학회:학술대회논문집
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• 2010.06a
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• pp.99-104
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• 2010

Nonlinear seal friction in pneumatic cylinders can impede the performance of pneumatic systems designed for high precision positioning with favorable high speed actuation. The behaviour of an elastomeric piston seal in high speed pneumatic cylinders is analysed by nonlinear finite element analysis using ABAQUS. The contact pressures, stress and strain distributions and frictional forces of the piston seal are simulated with variation of interference fits, supply pressures, friction coefficients and piston rod velocities. The nonlinear finite element model of the piston seal is used to predict deformation of a seal, friction force and contact pressure distributions.

• The korean journal of orthodontics
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• v.18 no.1 s.25
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• pp.55-63
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• 1988

It has been suggested that the frictional force between bracket and arch wire may impede the tooth movement. The present study was aimed to compare and analyze the effect of wire size, type of ligation, and duration of ligation on the magnitude of frictional force between cobalt chromium wire and stainless steel bracket under the artificial saliva. The results were as follows: 1. Type of ligation and size of wire were the main influencing factor on the level of friction. 2. Stainless steel ligature generated higher frictional forces than elastomeric module. 3. The rectangular wire consistently exhibited more frictional force values than round wires, while there was no significant difference between frictional forces of round wires. 4. In elastic ligature, frictional force decreased with time. 5. Artificial saliva had no significant influence on the frictional force between cobalt chromium wire and bracket.

• Journal of Korea Multimedia Society
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• v.22 no.1
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• pp.79-87
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• 2019

Appropriate strategies are needed to ensure long-term preservation of various types of electronic records. For proper preservation of electronic records, it is necessary of decision-making processes for risk assessment, notification and implementation of conservation measures. To do this, the task of assessing various risk factors that impede the long-term preservation and utilization of electronic records should be done first. In this study, since electronic records are mostly stored in file form, risk assessment for electronic records of file type is performed. The risk factors required for the risk assessment of the file format are derived, and the algorithms are developed to devise a calculation method of the weighting factor and the risk factor index for evaluating the risk based on the proposed risk factors. In addition, the proposed methods are applied to the file formats used in Korea and risk assessment is performed and the results are analyzed.

• Journal of Hospice and Palliative Care
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• v.23 no.4
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• pp.252-255
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• 2020

This article aims to discuss the barriers hindering cancer patients from receiving early palliative care, which has been demonstrated to be more effective in improving quality of life and controlling symptoms. Specifically, there are barriers in four aspects of delivering early palliative care. First, the difficulty of starting discussions about early palliative care and the lack of adequate appointment time can impede communication between oncologists and patients and their family members. Second, determining the timing of referral and deciding upon and applying a standard for referral can be barriers in the process of referral from oncology to palliative care. Third, palliative care patients and their family members can face difficulties regarding in what format and by whom the services will be delivered. Fourth, biases, misinformation, and inaccurate beliefs can be barriers in the process of patients and their family members accepting care. In order to facilitate early palliative care, research and policy regarding these barriers are necessary, along with efforts made by medical staff.

• International Journal of Computer Science & Network Security
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• v.22 no.11
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• pp.338-347
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• 2022

The current study aimed to identify the reality of the transitional services provided to people with intellectual disabilities from the parent's point of view. The results indicated an average level, with an arithmetic mean (3.66) of the reality of transitional services provided to students with intellectual disabilities through the response of the study participants to the questionnaire consisting of (20) items. The dimension (social and societal skills) ranked first with an arithmetic average (4.03) with a high degree, through the response of the participants in the study to the items of the dimension consisting of (10) items. It was followed by the dimension (self-determination skills) with an arithmetic average of (3.29) to a medium degree, through the response of the participants in the study to the items of the dimension consisting of (10) items. The researchers recommend the necessity of joint planning by all relevant authorities, to solve the legal, societal, technical, and administrative problems and challenges that impede the provision of transitional services for students with intellectual disabilities.

• Journal of Auto-vehicle Safety Association
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• v.14 no.2
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• pp.75-82
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• 2022

Automated vehicles (AVs) are coming to our roadways. In practice, there are still several challenges that can impede the AV sensors are polluted on various road conditions. In this paper, we propose a strategy for V2E performance assurance technology using Kano model. We are developing the vehicle sensor cleaning system about the three types of commonly used sensors: camera, radar, and LiDAR. Surveys were carried out in 30 AV's experts on quality characteristics about V2E performance assurance technology. As a result, the Kano model developed to verify a major requirement of autonomous vehicle's sensor cleaning system. It is expected that the Kano model will be actively used to verify the importance of V2E development strategy.