• Proceedings of the Korean Society of Precision Engineering Conference
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• 2008.06a
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• pp.533-534
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• 2008

• The Korean Journal of Ceramics
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• v.5 no.4
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• pp.386-389
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• 1999

Effect of high voltage screening was examined on mechanical strength of titania ceramics with two different surface roughness. Roughly finished sample showed degraded mechanical strength meaning that the introduced flaw played the role of starting point of mechanical fracture. On such sample, electrically weak parts were eliminated by applying a screening field. Mechanical strength measurement on survived parts revealed that after screening the Weibull plots bended to become a convex curve while plots at high strength region were almost the same. This result means that relatively low mechanical strength parts were eliminated by the electrical method. As a result the Weibull modulus calculated from all the data increased, demonstrating the effect of high voltage screening on titania ceramics containing fracture controlling surface flaws. Roles of the surface flaw such as a common weak spot for both failures are disscussed in relation to the electric field concentration similar to that of mechanical stress.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.373-377
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• 2003

Recently, advanced manufacturing systems with high speed and intelligence have been developed for the betterment of machining ability. In this case, reliability prediction work with motion characteristic evaluation of sliding cover(C-plate, Bellows, etc) has also important role from design procedure to manufacturing and assembly process. Accordingly in this study, H/W test-bed system for reliability evaluation of sliding cover has been developed to obtain proper reference data for design of new model, prevention trouble (failure mode), and improvement of quality and lift cycle extremely for advanced mother machinery.

• Journal of the Korean Society for Precision Engineering
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• v.34 no.2
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• pp.139-143
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• 2017

Finite element analysis was performed for a split-type CFRP bicycle frame, which was designed to apply a compression molding process with carbon fiber prepreg for a conventional bicycle. An epoxy adhesive material for joining the frames was selected by the extent of stress at joint interfaces. The split-type bicycle frame was then formed and its weak parts examined by the boundary conditions according to reliability tests. The results verified the reliability of the bicycle frame after modification of these weak parts. The finished product was manufactured by using this developed split-type bicycle frame.

• 한국태양에너지학회:학술대회논문집
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• 2009.11a
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• pp.222-226
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• 2009

The parts of building which has the most influence on thermal load are skins, outer walls and windows. Among them, window is the worst weak point of building even if it has many advantage of solar radiation gain than other parts. The present time, many researches on various performance of window and many types of system-window are being made. This study evaluates thermal performance of tilt & sliding system window by simulation program Therm 5.2 and Window 5.2. After making a sample model improving it's thermal weak point, this study evaluates real thermal performance of system window. As a result, this study understands manufacture ability condition of domestic company and proposes a research plan of system window.

• The Korean Journal of Pain
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• v.35 no.1
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• pp.78-85
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• 2022

Background: The current pandemic has affected people's health multidimensionally. This study aims to investigate musculoskeletal pain, sleep quality, depression levels, and their relationships in individuals belonging to different age groups during COVID-19 in Turkey. Methods: A web-based self-administered survey that consisted of demographic questions, The Beck Depression Inventory (BDI), Pittsburgh Sleep Quality Index (PSQI), and scores of musculoskeletal pain was sent to participants. Pearson correlation analysis was used for determining the statistical relationship between variables. Results: The study includes 1,778 participants. The highest percentage for mild, moderate, and severe pain was in the head (49.8%), back (15.5%), and head (11.5%), respectively. The PSQI-total had shown a weak correlation with pain levels in all body parts. The highest correlation for sleep quality and pain levels was between the PSQI-5 and lower back pain. There was a weak correlation between PSQI-2 and the BDI score, and a moderate correlation between the PSQI-1, PSQI-5, PSQI-7, PSQI-total, and BDI score. Pain in all body parts showed a weak correlation with depression level. Conclusions: This study showed that musculoskeletal pain was varied in body parts with different intensities according to age groups in Turkey during the pandemic. The most common pain was in the head, back, and lower back. Headache was found correlated with the parameters of sleep quality. Pain of the head, neck, back, lower back, and shoulder were correlated with sleep latency. Sleep quality was associated with depression and musculoskeletal pain, while musculoskeletal pain was correlated with depression.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.10a
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• pp.985-988
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• 2002

The Spindle-]fearing System is very important unit for geometrical accuracy in machine tools. To improve effectively the weak point of spindle system, it is necessary that the contribution ratio of spindle core parts to static and dynamic stiffness is clarified. In this paper, static contribution ratio of core parts is calculated by overlapping static deformation of basic spindle design with one flexible parts. The dynamic contribution ratio for natural frequency and dynamic deformation at spindle end is obtained by calculating correlation between original and basic spindle deformation, by curve fitting with regressive method. It is proved the validity of estimation result is correct.

• Honam Mathematical Journal
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• v.29 no.4
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• pp.701-721
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• 2007

Recently, a new singular function(NSF) method was posed to get accurate numerical solution on quasi-uniform grids for two-dimensional Poisson and interface problems with domain singularities by the first author and his coworkers. Using the singular function representation of the solution, dual singular functions, and an extraction formula for stress intensity factors, the method poses a weak problem whose solution is in $H^2({\Omega})$ or $H^2({\Omega}_i)$. In this paper, we show that the singular functions, which are not in $H^2({\Omega})$, also satisfy the integration by parts and note that this fact suggests the possibility of different choice of the weak formulations. We show that the original choice of weak formulation of NSF method is critical.

• Journal of the Korean Society of Costume
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• v.49
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• pp.65-72
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• 1999

The purpose of this study was to investigate the relationships between body-calthexis and clothing image preferences in male college students. The sample included 28 male college students and an instrument was developed based on the previous studies. The statistical analyses used for this study were factor analysis cluster analysis and t-test. The result of factor analysis showed that body-cathexis consisted of four areas of body parts: face/head upper body middle body and lower/total body. Clothing image preferences consisted of 'strong vs weak' 'soft vs hard' 'young vs mature' 'mannis vs feminine' and 'distinguished vs undistinguished' images. Cluster analysis revealed that male college students are segmented into two groups. and the two groups differed in regard to clothing image preferences such as 'strong vs weak' 'young vs mature' and 'mannish vs feminine' images. In addition the two consumer segments were different concerning body-cathexis for middle body and all body areas combined. The consumers who preferred feminine weak and mature clothing images were more satisfied with their middle area of the bodies and all body areas combined.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2000.11a
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• pp.653-657
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• 2000

The paper describes the contents and results of the national project named "Development of Computer Integrated Product Design for Automation Equipment". It is focussed on the real-time control '||'&'||' monitoring of manufacturing process for automobile rubber parts. Automobile rubber parts industy is one of the typical process that high11 depends upon manufacturing facilities and equipments. So. it requires high cost and engineering technolog) on plant implementation. But most companies of rubber parts industries are small or mid companies that habe weak abilities for plant implementation properly and systematically. Therefore, for upgrading the levelof automation. it is necessar). to dekelope the computer based management and monitoring slsteni that enables to build-up the common base of automation and systemization. 'Through this project. we developed low cost real-time monitoring system for banbun mixing process '||'&'||' mold injection process of rubbcr parts manufacturing, that is composed with DDCU(Distributed Digital Control Unit),signal interfaces to gathering mon~toring terms and speciall\ developed functional sofhare including some algorithm for management '||'&'||' process monitoring