• Korean Journal of Materials Research
• /
• v.10 no.1
• /
• pp.77-82
• /
• 2000

A surface of polytetrafluoroethylene(PTFE) was modified with changing ion doses by 1 keV $Ar^+$ ion irradiation and Cu films having thickness $5000\;{\AA}$ were deposited on the modified PTFE. The SEM study showed that the surface texture of modified PTFE was in the form of cones whose height increased depending on ion doses. Through XPS spectra, it was found that the intensity of F ls peaks decreased with ion doses by preferential sputtering of F atoms and the C-C and / or C-F chains were formed by the crosslinking in the newly unstable chains. Cu films were deposited uniformly along the filaments formed on the modified PTFE. In x-ray diffraction (XRD) spectra of deposited Cu films on modified PTFE, a preferred orientation along (111) and (200) planes was found and the peak intensity of (111) plane increased as surface roughness of modified PTFE increased. The resistivity of Cu films was changed from $2.7{\mu}{\Omega}cm$ of unmodified PTFE to $4.3{\mu}{\Omega}cm$ of modified PTFE at ion dose of $1{\times}10^{16}/\textrm{cm}^2$ and the abrupt increase of resistivity in the modified PTFE at ion dose of $1{\times}10^{17}/\textrm{cm}^2$ was due to being cut off the film which resulted from the increased surface roughness.

• Journal of Navigation and Port Research
• /
• v.29 no.7
• /
• pp.603-609
• /
• 2005

This paper presents the method for developing an optimum hull form with minimum wave resistance using SQP( sequential quadratic programming) as an optimization technique. The wave resistance is evaluated by a Rankine source panel method with non-linear free surface conditions and the ITTC 1957 friction line is used to predict the frictional resistance coefficient. The geometry of the hull surface is represented and modified using NURBS(Non-Uniform Rational B-Spline) surface patches. To verify the validity of the developed program the numerical calculations for Wigley hull and Series 60 Cb=0.6 hull are performed and the results obtained after the numerical calculations are compared with the initial hulls.

• Proceedings of the Korean Geotechical Society Conference
• /
• 2005.10a
• /
• pp.689-697
• /
• 2005

The soil nailing system at permanent slope reinforcement is used with various facing methods in Korea. Also, pressure-injected grout technique is variously applied to many structures. However, most design of the pressure-injected grout technique have been carried out empirically because of complicated mechanisms associated with the behavior of surrounding soils and the hardening process of cement grout. Therefore this study, a newly modified soil nailing technology named as the PGSN (Pressure Grouting Soil Nailing) system with fabric form is developed to increase the global stability. Up to now, the PGSN system has been estimated mainly focusing on an establishment of the design procedure. In the present study, numerical study are carried out to evaluate potential failure surface and minimum factor of safety including facing stiffness and expanded radius of cemented grout by SSR (Shear Strength Reduction) technique. Also, results of numerical analysis are carried out for the typical section of soil nails slope using $FLAC^{2D}$ program for expanded effective radius by pressure grouting.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.7 no.6
• /
• pp.57-64
• /
• 1999

Initial flame development and propagation were visualized under the new ignition system developed to estimate the effects of ignition characteristics on the engine performance in a port injection SI engine. Effects of intake air flow characteristics were also investigated by three different kinds of the swirl control valve. Experiments were performed in an optical single cylinder engine modified form a commercial engine. Flame images were captured through the quartz window mounted in the piston by the high speed video camera and analyzed to compare initial flame development. Results show that IMEP tends to rise slightly as the ignition duration gets longer. The direction of flame propagation is decisively governed by the in-cylinder flow motion. Every flame grows toward the exhaust valve forming a kind of turbulent flame. Initial flame propaagation characteristics are very similar to ones analyzed form pressure data.

• The Korean Journal of Pain
• /
• v.27 no.1
• /
• pp.16-22
• /
• 2014

Psychosomatic disorders are defined as disorders characterized by physiological changes that originate partially from emotional factors. This article aims to discuss the psychosomatic disorders of the oral cavity with a revised working type classification. The author has added one more subset to the existing classification, i.e., disorders caused by altered perception of dentofacial form and function, which include body dysmorphic disorder. The author has also inserted delusional halitosis under the miscellaneous disorders classification of psychosomatic disorders and revised the already existing classification proposed for the psychosomatic disorders pertaining to dental practice. After the inclusion of the subset (disorders caused by altered perception of dentofacial form and function), the terminology "psychosomatic disorders of the oral cavity" is modified to "psychosomatic disorders pertaining to dental practice".

• The Research Journal of the Costume Culture
• /
• v.8 no.4
• /
• pp.537-548
• /
• 2000

This paper focuses on development of a fashion design education course that will foster the talent and aesthetic consciousness of fashion design student. The writer reached the content of the designing ideas to practical applications as the defined scope of fashion design education. For designing idea in practical application : matching ideas, contrasting ideas, formative combinations and revisionism were used. For design ideas, the ideas developed by 飯塚弘子, 万江入重子, 香川達子 were used in revision. To detail the content of design education, fashion magazines, portfolios, photographs and related fashion design educational materials were used. 1. Matching ideas : it proposes such identical expression into costume by making a research of developing material, application form and color extraction from design sources. 2. Contrasting ideas : it proposes such opposite expression into costume by making a research of opposite to image, form, position and purpose from some object. 3. Formative combinations : it proposes such new expression into costume by combining a detail of costume with the other object. 4. Revisionism : it proposes such modified expression into costume by making a research of deletion, change, addition and conversion in costume.

• Proceedings of the IEEK Conference
• /
• 1999.06a
• /
• pp.323-326
• /
• 1999

This paper describes a point matching method that is based on an expansion of the electromagnetic field in terms of a series of Bessel and modified Bessel functions multiplied by trigonometric functions. In this method, the electric and magnetic fields inside the waveguide core are matched to those outside the core at matching points on the boundary to yield matrix equations. As an example applying this method, the paper presents the results of the computation in the form of curves of the propagation constants in a semicircular optical waveguide, be formed by annealing for reduced insertion(radiation) loss when connected to optical fiber. The propagation curves are presented in a form of refractive index independent. Also, it presents relative energy distributions between inside the core and outside the core of various modes and presents field distributions.

• Bulletin of the Korean Chemical Society
• /
• v.26 no.3
• /
• pp.413-417
• /
• 2005

Fluorescence of green fluorescent protein mutant, 2-5 GFP is observed during denaturation by guanidine. The fluorescence intensity decreases exponentially but the fluorescence lifetime does not change during denaturation. The fluorescence lifetime of the denatured protein is shorter than that of native form. As the protein structure is modified by guanidine, solvent water molecules penetrate into the protein barrel and protonate the chromophore to quench fluorescence. Most fluorescence quenchers do not affect the fluorescence of native form but accelerate the fluorescence intensity decay during denaturation. Based on the observations, a simple model is suggested for the structural change of the protein molecule during denaturation.

• Korean Journal of Child Studies
• /
• v.12 no.2
• /
• pp.67-77
• /
• 1991

An investigation of the effect of occupational information on vocational cognitive complexity was conducted with 331 male and female adolescents in ninth grade. There were 2 experimental groups and 1 control group. Experimental group I was given only occupational information sheets (written form information) while group II was given occupational information through verbal instruction in addition to the occupational information sheets. A modified form of the cognitive complexity grid originally developed by Bodden (1970) was utilized to collect data on the subjects' vocational cognitive complexity. ANOVA and $Scheff{\acute{e}}$ tests revealed that there were significant differences between experimental group II and the other groups in vocational cognitive complexity. The cognitive complexity level of experimental group I and the control group for the most aspired occupation was significantly lower than for the least aspired occupation. However, the cognitive complexity level of experimental group II for the most aspired occupation was higher than for the least aspired occupation. The results suggest that just giving occupational information to adolescents may not be effective and giving occupational information may be effective only when the method of giving occupational information is active enough to induce adolescents' self-confirming cognitive process.

• Bulletin of the Society of Naval Architects of Korea
• /
• v.12 no.1
• /
• pp.23-30
• /
• 1975

Because of the simplicity in analysis and design of steel structure, the connections of members are assumed either as perfectly hinged or rigidly fixed. However, a more economical design would result if the effect of restraint in connections were included in analyzing frame structure. From this point of view, stiffness matrices for member with bracketed connections are presented in the form of the stiffness matrices for member with variable moment of inertia, modified by a correction matrix, whose elements are functions of fixity factors of the connections. To obtain fixity factors, the displacements and stress distribution of bracketed connections are investigated by using of the degital computer program, which have been developed to make computing time shorten and the round off errors smaller. The relationship of moments and slip angle in bracketed connections are presented in the form of curves, which can be used in establishing a stiffness matrices for member with bracketed connections.