• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09a
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• pp.191-192
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• 2006

The deformation under radial pressure of rectangular dies for metal powder compaction has been investigated by FEM. The explored variables have been: aspect ratio of die profile, ratio between diagonal of the profile and die height, insert and ring thickness, radius at die corners, interference, different insert materials, i. e. conventional HSS, HSS from powders, cemented carbide (10% Co). The analyses have ascertained the unwanted appearance of tensile normal stress on brittle materials, also "at rest", and even some dramatic changes of stress patterns as the die height increases with respect to the rectangular profile dimensions. Different materials behave differently, mainly due to difference of thermal expansion coefficients. Profile changes occur when the dies are heated up to the temperature required for warm compaction. The deformation patterns depend on compaction temperature and thermal expansion coefficients.

• Journal of the Korean Society for Precision Engineering
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• v.16 no.3 s.96
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• pp.208-214
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• 1999

The purpose of this paper is to develop a profile modification technique of spur gears and its computer program for the prevention of gear tooth overlap. In the gear system, tooth overlap produces an impact at the initial contact of some tooth pairs. In this analysis, contact surface was assumed to be unbonded and frictionless under small deformation and stain. The problem is formulated by a variational statement with inequality constraint. Tooth load sharing is obtained by the application of contact theory, and overlap is known by the analysis of deformation. After carrying out the profile modification of gear tooth, we verified the reasonable results.

• Journal of Preventive Medicine and Public Health
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• v.38 no.1
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• pp.53-60
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• 2005

Objectives : To identify the relationship between the internet addiction of adolescents and their Health Promotion Lifestyle Profile and Perceived Health Status, and thereby to detect the impact of internet addiction on the health of adolescents, produce the basic information necessary to develop a prevention program for internet addiction and to plan for a health promotion program. Methods : This study was designed as a cross-sectional study, and the subjects were the second-grade students of three junior-high and three high schools located in the city of K in Kyung Gi Province. Out of 769 subjects, 764 completed the questionnaires (99.3%); 369 (48.3%) junior-high school students and 395 (51.7%) high school students. The questionnaires were composed of Young's Internet Addiction, Health Promotion Lifestyle Profile, Perceived Health Status, and general characteristics. We used t-test, ANOVA in means comparison between groups, X2-test in frequency analysis, and multiple regression analysis in multivariate analysis, using the SAS $8.1^{\circledR}$ program. Results : There was a statistically significant difference in Health Promotion Lifestyle Profile according to internet addiction status (severe addiction vs. other status, p<0.0001). The Perceived Health Status scores was lowest in the severe addiction group (p<0.001). There was also a significant negative correlation between internet addiction and Health Promotion Lifestyle Profile (p<0.0001). The results of multiple regression showed that Young's Addiction Score was significant for the subjects' Health Promotion Lifestyle Profile after controlling for other variables (p<0.0001). Conclusions : This study showed that the severe internet addiction group had the lowest score in Health Promotion Lifestyle Profile and Perceived Health Status, which suggests that the addiction could have a negative effect on the health status of adolescents.

• Korean Journal of Culture and Social Issue
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• v.27 no.2
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• pp.167-189
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• 2021

The purpose of this study was to classify different profiles of grit (effort vs. interest) and passion mindset (fixed vs. growth) in university students and to understand whether there are differences in psychological characteristics (ie. depression, anxiety and happiness) and career adaptability between the profiles. To this end, we recruited 359 students aged 18 and 25 and applied a Latent Profile Analysis(LPA). The results revealed 4 distinct profiles : Profile1-a burgeoning type, Profile2-an ordinary type, Profile3-a fixed/limited type, Profile4-sprouting/drifting type. The profile1(LP1, 22.2%) had high levels of grit and passion growth mindset. The profile2(LP2, 63.8%) showed average levels in both grit and passion mindset. The profile3(LP3, 8.8%) had a low level of grit and a high level of passion fixed mindset. The profile4(LP4, 5.1%) showed a low level of grit and a high level of passion growth mindset. The four profiles were distinct in psychological characteristics and career adaptability. The burgeoning type(profile1) was most adaptive in comparison to the fixed/limited type(profile 3). These results suggest that grit has more powerful effects on psychological characteristics while passion growth mindset exerts stronger influencers in career adaptability. Putting the results together, our findings imply that both passion growth mindset and grit need to be considered together to enhance the individuals' comprehensive well-being and to increase the level of adaptation for career preparation.

• Korean Institute of Interior Design Journal
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• no.31
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• pp.56-63
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• 2002

This study intends to prepare a system that can be used, by applying digital technique, in analyzing complexity of architectural forms that have been visualized by the correlation based on the distribution chart made in accordance with profile lines. The profile lines are derived from the edge analysis of the architectural forms, simplified based on the visual theory. For the purpose, this study was conducted in the following ways: First, problems of the existing models for the elevation analysis were examined along with formal analysis based on visual recognition to consider the profile lines derived from the forms. Secondly, in elevation analysis, profile lines were derived by digital method to measure them qualitatively. To verify the objectivity of the measured data value, a survey was conducted based on the adjective cataloging method, and the correlation of the survey result and analyzed data was analyzed to verify the validity of the derived data. Thirdly, supplementation for the problems deducted from experiments and the possibility to use it in designing were suggested. Digital method has many advantages over the conventional analyzing system in deriving precise data value by excluding subjectivity. It also allows various analytical methods in analyzing numerous data repeatedly. Diversified models and methods of analysis considering numerous factors arising in the process of designing remain assignments to research in future.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2008.10a
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• pp.110-113
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• 2008

This study was performed to predict the shape of polymer extrusion product and to find the cause of defective products Experiments was performed to extrude the complex profile shape using PC/ABS composite resin with new profile die and cooling die. A finite element analysis for the Polymer Extrusion process considering the heat transfer and thermal deformation was also performed, and the result was compared with the experimental data. It is found that the predicted profile shape in F. E. M was similar to the experimental result and the thickness of extruded product was thin when the velocity of profile die outlet was slow than the velocity of production (2m/min).

• Communications for Statistical Applications and Methods
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• v.27 no.1
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• pp.15-35
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• 2020

In research on behavioral studies, significant attention has been paid to the stage-sequential process for multiple latent class variables. We now explore the stage-sequential process of multiple latent class variables using the multivariate latent class profile analysis (MLCPA). A latent profile variable, representing the stage-sequential process in MLCPA, is formed by a set of repeatedly measured categorical response variables. This paper proposes the extended MLCPA in order to explain an association between the latent profile variable and the latent group variable as a form of a two-dimensional contingency table. We applied the extended MLCPA to the National Longitudinal Survey on Youth 1997 (NLSY97) data to investigate the association between of developmental progression of depression and substance use behaviors among adolescents who experienced Authoritarian parental styles in their youth.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2003.05a
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• pp.164-167
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• 2003

Profile ring rolling process is simulated by using the general purpose commercial finite element analysis software MSC.Superform Because the deforming region is restricted to the vicinity of the roll gap, only a ring segment spanning the roll gap is analysed in order to save computation time and cost. A profile ring with an external round groove is chosen as an example to be analysed. The rolls with and without groove were analysed to compare the amount of side spread. It is found that the grooves in the rolls reduce the amount of side spread.

• Transactions of Materials Processing
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• v.24 no.2
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• pp.107-114
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• 2015

The current study presents a geometric measurement and analysis of the section profile for a feature line surface on an automotive outer panel. A feature line surface is the geometry which is a visually noticeable creased line on a smooth panel. In the current study the section profile of a feature line surface is analyzed geometrically. The section profile on the real press panel was measured using a coordinate measuring machine. The section profiles from the CAD model and the real panel are aligned using the same coordinate system defined by two holes near the feature line. In the aligned section profiles the chord length and height of the curved part were measured and analyzed. The results show that the feature line surface on the real panel is doubled in width size.

• Proceedings of the KSR Conference
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• 2005.11a
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• pp.146-151
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• 2005

Main parameters of wheel-rail combination are investigated by profile analysis. A rolling radius difference is one of the main characteristics that describe a contact between wheelset and railway track, which in turn defines the dynamic behavior of a wheelset. This paper describes functional relation between lateral wheelset displacement and rolling radius difference or conicity on new/worn wheel of existing narrow gauge vehicle. Information about curving behavior and running stability are given by this both relations. The optimal wheel profile for railway vehicle with narrow gauge is adopted through this analysis. And, the applicable limit value of conicity which is used in order to do dynamic simulation of vehicle is presented.