• Tribology and Lubricants
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• v.17 no.3
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• pp.236-243
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• 2001

In this study, flow factors are evaluated in terms of kurtosis using random rough surface generated numerically. As h/$\sigma$become large ø$\sub$x/, ø$\sub$y/, ø$\sub$fp/, approach to 1 and ø$\sub$s/, ø$\sub$fs/ to 0 asymptotically regardless of kurtosis. ø$\sub$x/, ø$\sub$y/, ø$\sub$fp/ increase with increasing kurtosis in the mixed lubrication regime. ø$\sub$s/, ø$\sub$fs/ is associated with an additional flow transport due to the combined effect of sliding and roughness. As h/$\sigma$ decreases ø$\sub$s/, ø$\sub$fs/ increase up to a certain point, and then decrease toward zero. This behavior can be attributed to the increasing number of contacts in the mixed lubrication regime. ø$\sub$x/ in the presence of elastic deformation on the surface is larger than ø$\sub$x/ in the absence of it because local film thickness(h$\sub$T/) increases by elastic deformation.

• Journal of the Korean Society of Clothing and Textiles
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• v.42 no.3
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• pp.411-427
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• 2018

This study is to understand the inner psychological state of consumers who pursue a retail therapy effect through fashion product shopping. Qualitative research on the whole process from the point of time of occurrence of shopping motivation to the end of shopping motivation was performed. The researcher became a virtual shopping partner during shopping and conducted a natural conversation interview using a mobile instant messenger program (Kakao Talk). After shopping, participants were asked to write a diary on that day. Collected data were analyzed by applying the grounded theory approach suggested by Strauss and Corbin (1998). Casual Condition, represented everyday stress and Contextual Condition indicated the self-healing consumption trend. Main Phenomena showed a mood change during the fashion shopping process. The sense of emancipation from the place, the satisfaction from the maintenance of social relations, and the sense of accomplishment through purchases were revealed. Intervening Condition showed the consideration in the process of shopping for fashion products, such as providing a try-on experience, price promotion, and involvement of a companion. Action Interaction Strategy was the shopping behavior for the positive emotion increase and negative emotion decrease. Consequence represented a retail therapy in shopping for fashion products.

• Structural Engineering and Mechanics
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• v.71 no.2
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• pp.153-163
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• 2019

Longitudinal fracture behavior of non-linear elastic beam configurations is studied in terms of the strain energy release rate. It is assumed that the beams exhibit continuous material inhomogeneity along the width as well as along the height of the crosssection. The Ramberg-Osgood stress-strain relation is used for describing the non-linear mechanical behavior of the inhomogeneous material. A solution to strain energy release rate is derived that holds for inhomogeneous beams of arbitrary cross-section under combination of axial force and bending moments. Besides, the solution may be applied at any law of continuous distribution of the modulus of elasticity in the beam cross-section. The longitudinal crack may be located arbitrary along the beam height. The solution is used to investigate a longitudinal crack in a beam configuration of rectangular cross-section under four-point bending. The crack is located symmetrically with respect to the beam mid-span. It is assumed that the modulus of elasticity varies continuously according a cosine law in the beam cross-section. The longitudinal fracture behavior of the inhomogeneous beam is studied also by applying the J-integral approach for verification of the non-linear solution to the strain energy release rate derived in the present paper. Effects of material inhomogeneity, crack location along the beam height and non-linear mechanical behavior of the material on the longitudinal fracture behavior are evaluated. Thus, the solution derived in the present paper can be used in engineering design of inhomogeneous non-linear elastic structural members to assess the influence of various material and geometrical parameters on longitudinal fracture.

• Child Health Nursing Research
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• v.4 no.1
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• pp.116-127
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• 1998

The purpose of this study was to examine the reliability of Q-sorting and to develope a typology of coping to stress in school-age children through the use of Q-methodology. For the study, Q-statements are selected from the literature and interviews of 30 Children, A total number 153 statement were collected and 31 Q-samples were finally selected. AP-sample of 76 was selected the elementary school children. Each of respondents were given 31 coping strategies questionnaire and set of 31 statements with cartoon on each of cards and sorted them according to the 9-point scale. The result of the C-sorting by each subject were coded and analyzed using the QUANAL PC and SPSS PC＋ program. As a result of the analysis, There were significant relationship between score each item of question naire and score of sorted statement. Therefore, school-age children was able to Q-sorting(forced normal distribution). Also, the four types of coping were named as follows : Type I (n=35) : To search for the dynamic behaviors Type II (n=12) : To search for the intellectual behaviors Type III (n=22) : To search for emotional-spiritual behaviors Type IV (n=7) : To search for the self-abuse behaviors Throught the study, the implication for teachers, parents and school nurses is that there is needed to guide and to support adaptive coping behaviors. Also, it is recommended that the application of Q-methodology for study of children's subjective concepts like stress and coping.

• Journal of Navigation and Port Research
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• v.41 no.3
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• pp.93-102
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• 2017

When VTSOs (Vessel Traffic Service Operator) determine the degree of collision risk for two vessels, they consider comprehensive information about each vessel's course, speed, DCPA, TCPA, and encountering situation. In this study, we proposed a utility function based on the risk attitudes of VTSOs toward the Risk Index (RI). The RI was calculated using the risk of encounter, the risk of approach, and the risk of time for two vessels in order to predict each ship's collision risk from the VTS viewpoint. We obtained each coefficient of the RI and the risk attitude through a survey of collision risks among VTSOs of Korea. In order to verify whether the proposed utility is reasonable, we validated by applying the degree of collision risk to some historical cases of accidents in Busan port along with the Ship of ES value($ES_S$) of ES(Environmental Stress) model.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.52 no.4
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• pp.458-468
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• 2007

To tolerate environmentally adverse conditions such as cold, drought, and salinity, plants often synthesize and accumulate proline in cells as compatible osmolytes. ${\Delta}^1$-Pyrroline-5-carboxylate synthetase(P5CS) catalyzes the rate-limiting step of proline biosynthesis from glutamate. Two complete genes, MtP5CS1 and MtP5CS2, were isolated from the model legume Medicago truncatula by cDNA cloning and bacterial artificial chromosome library screening. Nucleotide sequence analysis showed that both genes consisted of 20 exons and 19 introns. Alignment of the predicted amino acid sequences revealed high similarities with P5CS proteins from other plant species. The two MtP5CS genes were expressed in response to high salt and low temperature treatments. Semi-quantitative reverse transcription-polymerase chain reaction showed that MtP5CS1 was expressed earlier than MtP5CS2, indicating differential regulation of the two genes. To evaluate the reverse genetic effects of nucleotide changes on MtP5CS function, a Targeting Induced Local Lesions in Genomes approach was taken. Three mutants each were isolated for MtP5CS1 and MtP5CS2, of which a P5CS2 nonsense mutant carrying a codon change from arginine to stop was expected to bring translation to premature termination. These provide a valuable genetic resource with which to determine the function of the P5CS genes in environmental stress responses of legume crops.

• Tunnel and Underground Space
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• v.26 no.3
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• pp.166-180
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• 2016

The present study numerically simulated the CO2 injection into the saline aquifer of CO2CRC Otway pilot project and the resulting hydrological-mechanical coupled process in the storage site by TOUGH-FLAC simulator. A three-dimensional numerical model was generated using the stochastic geological model which was established based on well log and core data. It was estimated that the CO2 injection of 30,000t over a period of 200 days increased the pressure near the injection point by 0.5 MPa at the most. The pressure increased rapidly and tended to approach a certain value at an early stage of the injection. The hydrological and mechanical behavior observed from the CO2 flow, effective stress change and stress-strength ratio revealed that the CO2 injection into the saline aquifer under the given condition would not have significant effects on the mechanical safety of the storage site and the hydrological state around the adjacent fault.

• Journal of Aerospace System Engineering
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• v.18 no.3
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• pp.17-26
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• 2024

Aircraft engines are exposed to high temperatures, high pressures, and stress caused by the rotation of the turbine shaft during flight. These loads can result in microcracks both on the inside and outside surfaces of the structure. Consequently, this can lead to structural defects and negatively impact the lifespan of the parts. To proactively prevent these defects, a finite element analysis is carried out to identify cracks. However, this process is time-consuming and requires significant effort due to the repetitive nature of crack modeling. This study aims to develop a crack modeling method based on the finite element model. To achieve this, the Constrained Delaunay Triangulation (CDT) technique is employed to triangulate the space while considering limitations on point connections. The effectiveness of this method is validated by comparing stress intensity factors for semi-elliptical cracks in plates and cylindrical vessels. This approach proves to be a valuable tool for crack analysis studies.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.37 no.10
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• pp.1229-1237
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• 2013

In this study, the theory of spherical indentation based on incremental plasticity is extended to an indentation method for evaluating creep properties. Through finite element analysis (FEA), the point where the elastic strain effect is negligible and the creep strain gradient constant is taken as the optimum point for obtaining the equivalent strain rate and stress. Based on FE results for spherical indentation with various values of creep exponent and creep coefficient, we derive by regression an equation to calculate creep properties using two normalized variables. Finally a program is generated to calculate creep exponent and creep coefficient. With this method, we obtain from the load-depth curve creep exponents with an average error of less than 1.5 % and creep coefficients with an average error of less than 1.0 %.

• The Journal of Korean Association of Computer Education
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• v.16 no.6
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• pp.1-10
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• 2013

Until now, the study of Internet addiction have focused on (1)Internet overuse (2)addiction (3)the real situation of disability in order. This approach have given a social awareness about Internet addiction as well as have been used as base for introduction of psychological and emotional means to prevent and treat Internet addiction. However, There are very few an ethical approach that is related in human values that what purpose does people use Internet for and how to use Internet. Accordingly, This study provides teleological, deontological, virtue and responsible ethics of Internet addiction. And, this study insist that Internet addiction is a wrongdoing on the basis of four ethical views. Based on these claims, this study stress the needs for Internet ethical education as a program to prevent and treat Internet addiction and se to tu1rn pop1 computer ethics into theoretical computer ethics.