• Proceedings of the KWS Conference
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• 2006.05a
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• pp.310-312
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• 2006

Self-piercing riveting(SPR) is becoming an important joining technique for automotive application of various material sheets and shapes. Fatigue behavior of SPR conections needs to be investigated experimentally and numerically to predict SPR fatigue lives. The simulations of various SPR specimens (Coach-Peel specimen, Cross-Tension specimen, Tensile-Shear specimen, Pure-Shear specimen) are performed to predict the fatigue life of SPR connections under different material combinations. Finite element models of various SPR specimens are developed using a FEMFAT SPOT SPR pre-processor. The fatigue lives of SPR specimens are predicted using a FEMFAT 4.4e based on the liner finite element analysis.

• 한국초전도학회:학술대회논문집
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• v.10
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• pp.27-34
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• 2000

HTS wires processed by PIT method are now available for magnet applications. But, those wires can not be used over 40 K due to weak link. This leads to necessity of development of coated conductor which can retain high $J_c$ at high field in liquid nitrogen. In this paper, various technical issues and the R&D status for both PIT wires and coated conductor were discussed. The difference of coated conductor's processes were also investigated and summarized. Various requirements for a design of HTS magnets were discussed. Anisostropic $J_c$ property with respect to magnetic field was considered to determine the coil's critical current. Low n value is a critical parameter to degrade a field stability with respect to time for a persistent mode HTS magnet. The relation between the margin of operation current and n value was investigated. Prototype HTS magnets with PIT wires are being developed for various applications such as crystal growth, MRI, magnetic separator and etc. HTS magnets will come into wide use in various fields of industries if the HTS wires with a low performance cost is developed.

• Journal of the Korea Institute of Building Construction
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• v.5 no.2 s.16
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• pp.97-105
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• 2005

Concrete structures in the marine environment often deteriorate in the early stage of their service life because of contact with various aggressive conditions. In recent years, the researches on the concrete in the marine environment have been carried out to increase their service life. In this experimental study, the concrete specimens were prepared with various adding contents of inorganic antifouling agent$(0\~3.0wt\%)$ composed of some fluosilicate solution. For evaluation of the properties of concretes containing inorganic antifouling agent, various tests such as setting time, slump loss, compressive strength, water absorption rate, fleering and thawing resistance and SEM of concrete, were conducted. As the results, physical and chemical properties of concretes were improved with an adding of inorganic antifouling agent. From the results of various tests, the optimal adding contents of antifouling agent was $1.0wt\%$.

• Korean Institute of Interior Design Journal
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• v.16 no.5
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• pp.55-62
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• 2007

Modern public library is expanding its role as generalized cultural facility. Therefore public library that has comfortable and physical environment for various age and various users are needed. The purpose of this research is to evaluate the application of universal design in common space of public library, and trying to suggest environmental improvement plan that various users could comfortably use the library based on its data. The scope of this research were adjusted as 8 public libraries located in Seoul and metropolitan area of Seoul. Spacial scope that was set of this research was common space of public library and scope of content was about application of universal design. As a result of the research, first, the application of universal design toward common space of public library were appeared as low. Second, constant management and application development of universal design is needed. Third, as roles and functions of public library become various from now on, application of delicate universal design is needed for intention of users.

• Sleep Medicine and Psychophysiology
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• v.1 no.2
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• pp.117-124
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• 1994

Obstructive Sleep Apnea Syndrome(OSAS), that is a complex disease of neuromuscular, respiratory and cardiovascular system, can be cured by various treatment such as weight control, medical and surgical intervention. As most of OSAS may be caused by various anatomical abnormalities, preoperative evaluation for exact anatomical site of obstruction must be needed. And various diagnostic procedures such as fiberoptic nasopharyngoscopy, Mueller test, cinefluoroscopy, cephalometry, computerized tomography, polysomnography would be used for this purpose. Uvulopalotopharyngplasty is currently the most popular method for the patient with OSAS among various surgical maneuvers and is very effective for the relieving the symptoms as like snoring, daytime somnolence, and nocturnal restlessness etc. Although subjective improvement is not compatible with it's objective assessment in postoperative evaluation for it's results, uvulopalatopharyngoplasty could be a recommandable surgical procedure because of it's ample effectiveness in promoting symptom improvement without any risk of serious complications.

• Journal of Mechanical Science and Technology
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• v.18 no.1
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• pp.145-152
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• 2004

Effects of various baffle designs on acoustic characteristics in combustion chamber are numerically investigated by adopting linear acoustic analysis. A hub-blade configuration with five blades is selected as a candidate baffle and five variants of baffles with various specifications are designed depending on baffle height and hub position. As damping parameters, natural-frequency shift and damping factor are considered and the damping capacity of various baffle designs is evaluated. Increase in baffle height results in more damping capacity and the hub position affects appreciably the damping of the first radial resonant mode. Depending on baffle height, two close resonant modes could be overlapped and thereby the damping factor for one resonant mode is increased exceedingly. The present procedure based on acoustic analysis is expected to be a useful tool to predict acoustic field in combustion chamber and to design the passive control devices such as baffle and acoustic resonator.

• The Transactions of the Korea Information Processing Society
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• v.7 no.2S
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• pp.692-700
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• 2000

As the multimedia application services have been getting various in Internet, need of multimedia database management system which can manage various multimedia information effectively has been increased. The multimedia application generally needs the features to store, manage, retrieve the multimedia data. We need a database management system framework that may be easily integrated with these features. This paper proposes th database management system framework providing the easy integration with various multimedia information retrieval. The framework uses OQL as the retrieval interface, so that user can use it easily. It can be integrated dynamically and easily with various multimedia retrieval method as a loosely coupled system. In addition there is no performance degradation caused in a loosely coupled system.

• Journal of Korean Society for Quality Management
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• v.30 no.2
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• pp.130-151
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• 2002

This paper investigates the relation between the Process capability index(PCI) and the quality assurance level under various conditions. The effect of the off-targetness of the process mean, deviation from the nomality, the estimation error, and tile measurement error on the quality assurance level is evaluated. Various distributions such as the Student-t, the chi-square, the gamma, the Weibull, and the log-normal distributions are considered to evaluate the deviation from the nomality. The quality levels under abnormal conditions turn out to be severely different from that under the standard condition. We provide tables and graphs of the quality assurance level on various abnormal conditions. In order for the industry users to use the PCI properly, they should refer to the tables and graphs, especially when they are not certain about the standard assumptions on which the PCI depends.

• Journal of Korean Society for Quality Management
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• v.48 no.2
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• pp.345-359
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• 2020

Purpose: Financial independence of the museum is an urgent issue in Korea. In this paper, methodology to combine arts and culture facilities with senior society is investigated based on case study of various senior programs in other countries. Methods: In this paper, case study of various senior programs from cultural and arts facilities in other countries are investigated in the aspect of public nature and independent management. Based on the analysis of the case study, optimal methodology is derived. Results: Based on case study of various senior program in other countries, it is clear that art and cultural facilities play important roles in participating elderly people to various social activities through developing programs specialized for elderly people. Conclusion: From analysis of the case study, senior program from arts and culture facilities provides more familiar contents rather than professional contents. Also, they consider more on communication and cooperation with local society to develop the senior program, which fulfill both public nature and financial independence.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 1999.11a
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• pp.49-56
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• 1999

A material was formulated with Phenol novolac and HEXA only. The cure kinetics and thermal characteristics of phenol novolac with various HEXA contents were peformed by differential scanning calorimetry and thermal gravimetric analysis. All kinetic parameters of the curing reaction including the reaction order, activation energy, and rate constant were calculated and reported. The results indicate that the curing reaction goes through an autocatalytic kinetic mechanism. The friction and wear characteristics of this material were determined using friction material testing machine. The friction coefficient of phenol novolac with various HEXA contents was determined using the PV(pressure & velocity) factor. The most stable and highest friction coefficient with a various pressure and velocity condition was found at HEXA 10 wt.% material. The specific wear rate per unit sliding distance with a various HEXA contents was reported.