• Tribology and Lubricants
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• v.20 no.2
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• pp.51-57
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• 2004

Micro/nano adhesion and friction properties of mixed self-assembled monolayer (SAM) with different chain length for MEMS application were experimentally studied. Many kinds of SAM having different spacer chains(C6, C10 and C18) and their mixtures (1:1) were deposited onto Si-wafer, where the deposited SAM resulted in the hydrophobic nature. The adhesion and friction properties between tip and SAM surfaces under nano scale applied load were measured using an atomic force microscope (AFM) and under micro scale applied load were measured using ball-on-flat type micro-tribotester. Surface roughness and water contact angles were measured with SPM (scanning probe microscope) and contact anglemeter. Results showed that water contact angles of mixed SAMs were similar to those of pure SAMs. The morphology of coating surface was roughened as mixing of SAM. Nano adhesion and nano friction decreased as increasing of the spacer chain length and mixing of SAM. Micro friction was decreased as increasing of the spacer chain length, but micro friction of mixed SAM showed the value between pure SAMs. Nano adhesion and friction mechanism of mixed SAM was proposed in a view of stiffness of spacer chain modified chemically and topographically.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.7 no.5
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• pp.1002-1012
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• 2003

An algorithm is suggested for collision avoidance of two-arm robot manipulator using redundancy. End-effectors of each redundant arm should move along each prescribed straight path to complete the given task, while avoiding collision with each other. Self-motion, considered as motion of each axis not to change the position and orientation of end-effector, is utilized in order to solve this problem. At each sampling time, self-motion is executed with the view to making farther between the links of each arm. Simulation results for two-arm robot manipulator, which has 9-d.o.f. respectively, are illustrated to show the performance of the algorithm.

• Journal of Internet Computing and Services
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• v.13 no.5
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• pp.93-104
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• 2012

Significant advancements in technology enhanced the reliability of navigation systems that are in use today. The GPS is the most widely used technique for satellite-based location estimation. However, systems based on GPS can only be accurate in providing location data when there is a clear view of the satellites. This paper proposes a self-contained navigation system that does not depend on any tracking infrastructure. Using the built-in sensors of a smartphone and a self-contained map, we implemented an accurate car locator. Evaluation results show that our proposed system outperforms GPS in providing accurate car location assistance.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2003.11a
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• pp.56-63
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• 2003

Micro/nano adhesion and friction properties of mixed self-assembled monolayer (SAM) with different chain length for MEMS application were experimentally studied. Many kinds of SAM having different spacer chains(C6, C10 and C18) and their mixtures (1:1) were deposited onto Si-wafer, where the deposited SAM resulted in the hydrophobic nature. The adhesion and friction properties between tip and SAM surfaces under nano scale applied load were measured using an atomic force microscope (AFM) and micro scale applied load were measured using ball-on-flat type micro-tribotester. Surface roughness and water wetting angles were measured with SPM (scanning probe microscope) and contact anglemeter. Results showed that wetting angles of mixed SAMs showed the similar value of pure SAMs. The coating surface morphology was increased as mixing of SAM. Nano adhesion and nano friction decreased as increasing of the spacer chain length and mixing of SAM. Micro friction was decreased as increasing of the spacer chain, but micro friction of mixed SAM showed the value between pure SAMs. Nano adhesion and friction mechanism of mixed SAM was proposed in a view of stiffness of spacer chain modified chemically and topographically.

• Smart Structures and Systems
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• v.17 no.4
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• pp.611-629
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• 2016

This study presents a new approach of surrogate modeling for time-consuming finite element analysis. A surrogate model is widely used to reduce the computational cost under an iterative computational analysis. Although a variety of the methods have been widely investigated, there are still difficulties in surrogate modeling from a practical point of view: (1) How to derive optimal design of experiments (i.e., the number of training samples and their locations); and (2) diagnostics of the surrogate model. To overcome these difficulties, we propose a sequential surrogate modeling based on Gaussian process model (GPM) with self-adaptive sampling. The proposed approach not only enables further sampling to make GPM more accurate, but also evaluates the model adequacy within a sequential framework. The applicability of the proposed approach is first demonstrated by using mathematical test functions. Then, it is applied as a substitute of the iterative finite element analysis to Monte Carlo simulation for a response uncertainty analysis under correlated input uncertainties. In all numerical studies, it is successful to build GPM automatically with the minimal user intervention. The proposed approach can be customized for the various response surfaces and help a less experienced user save his/her efforts.

• Journal of the Korean Data and Information Science Society
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• v.21 no.6
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• pp.1091-1100
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• 2010

The purpose of this study is to investigate by questionnaire method the guardian's mental attitudes and self-esteem toward their children with muscular dystrophy according to the sex, the age, the academic background, the family budget monthly income, the children's grade, the body ability, the muscular dystrophy recognition lapse, and religion. The guardian's mental attitudes toward their children with muscular dystrophy regarding the consultation hope, the basic recognition, the child custody, the personnel relationship and the childcare, the view of the future are very closely connected with each category and they are various from the whole categories.

• Korean Institute of Interior Design Journal
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• v.23 no.1
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• pp.114-121
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• 2014

Rikyu-Konomi and Enshu-Konomi accomplished the base of Japanese Dado as well as has set Japanese representative traditional culture. These are the products of the spiritual culture completed by the ideas of Sen Rikyu and Kobori Enshu, that are Wabi spirit and Kirei sabi spirit combined with the tea. This study is about the interpretation of Japanese traditional space designs related to Rikyu-Konomi and Enshu-Konomi as Japanese Traditional spiritual archetype. The process of this study is illustrated as follows: At first, it mentions the concept of Konomi as self-organizing system, and esthetic characteristics of Rikyu-Konomi and Enshu-Konomi. Secondly, it clarifies internal meanings and spacial characters of Konomi in the Japanese traditional space through the exploring Taian tea house as the example of Rikyu-Konomi, and Bosen tearoom and Katsurarikyu as the examples of Enshu-Konomi. Thirdly, it ascertains Rikyu-Konomi and Enshu-Konomi represented in the contemporary architectural spaces. It analyses the relation between modern traditional space designs and traditional archetypal vocabularies, and examines those spaces from an esthetic point of view for modern implication of Rikyu-Konomi and Enshu-Konomi. In conclusion, it clarifies the contemporary significance of Rikyu-Konomi and Enshu-Konomi in terms of japan traditional space design.

• Advances in concrete construction
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• v.10 no.3
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• pp.257-269
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• 2020

The aim of this study is to investigate the flexural performance of hybrid fiber reinforced self-compacting concrete (HFRSCC) having different ratio of micro and macro steel fiber. A total of five mixtures are prepared. In all mixtures, the sum of the steel fiber content is 1% and also water/binder ratio is kept constant. The amount of high range water reducer admixture (HRWRA) is arranged to satisfy the workability criteria of self-compacting concrete. Four-point bending test is carried out to analyze the flexural performance of the mixtures at 28 and 56 curing days. From the obtained load-deflection curves, the load carrying capacity, deflection and toughness values are investigated according to ASTM C1609, ASTM C1018 and JSCE standards. The mixtures containing higher ratio of macro steel fiber exhibit numerous micro-cracks and, thus, deflection-hardening response is observed. The mixture containing 1% micro steel fiber shows worst performance in the view of all flexural parameters. An improvement is observed in the aspect of toughness and load carrying capacity as the macro steel fiber content increases. The test results based on the standards are also compared taking account of abovementioned standards.

• Journal of Korean Academy of Nursing Administration
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• v.2 no.2
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• pp.17-42
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• 1996

Most human behaviors are based on self-perceptual image. Subjectivity in professional nursing image is shown in their opinions, beliefs, values, and attitudes of professional nursing and it helps to understand individual's behavior. This study was initiated to find the characteristics and patterns in subjectivity of hospital nurses' professional nursing image. The Data were collected from Apr. 20 to Aug. 22, 1996. The research method employed Q-methodology which is based on self-psychology and abductive logics. Analysis of Q-type obtained by QUANL pc program. The characteristics of professional nursing image was analyzed based on the typal array, extreme comments, and the subject's demographic information. The results revealed that there are three different types on the professional nursing image. The three types were named as follows : The first type, the Improvable, consisting of 6 subjects, preferentially perceived nursing is human behavior as life process, coordinating with other health personnel for the patients as nurses' important role. On the other hand, they are taking a little dissatisfied view of professional nursing image, which can be estimated to advance for the construction of the professional nursing image. The second type, the Self-conflicted, consisting of 13 subjects, who have the subjectivity of the image by focusing on external and environmental factors rather than developing positive individual nurses' image for their profession. They have very conflic-ting and self-degrading traits. The third type, the Affirmative, consisting of 10 subjects, who appreciate the essence of nursing, and that they highly perceived nurse' positive attitude, devotion, mature interrelationship and self-developing efforts etc. In conclusion, this study discovers three types on the professional nursing image and their relationship. By identifying the nature of three types, this study suggests that the results should be useful reinforcement tool in educating nursing students as well as in continuing education for hospital nurses.

• The Journal of the Korea Contents Association
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• v.8 no.6
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• pp.242-252
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• 2008

This article was examines an attitude towards Tourism Development that has relevance to social psychological differences of individuals in terms of social psychological research on Tourism Development. It used the self-monitoring scale developed by Snyder(1974) who focused on individual behavior, which has been recently paid attention in the field of social psychology. It is considered that the result of this study contributes to academic world from two extensive points of view. One is that this study was conducted without any previous studies on self-monitoring and was performed to arrange the concept of Tourism Development Attitude in the stream. Another one is that this research proved the influence of self-monitoring on the citizen's propensity towards Tourism Development Attitude toward economic impact, Tourism Development Attitude toward social impact and with the tendency of participating in tourism development. Finally, Tourism Development Attitude that has relevance to social psychological differences of individuals.