• Journal of the Korean Society of Manufacturing Technology Engineers
• /
• v.9 no.4
• /
• pp.41-47
• /
• 2000

In this study, the purpose finds out the best welding conditions for bonding of electric wire by ultrasonic welding. The material was plastic-insulating low-voltage-cabels for automobiles. The experiment varied the values of welding time and welding pressure and fixed the values of amplitude and energy. With the facts, the best condition for ultrasonic welding to achieve bonding exactly is gained according to the size of the cross-sectional area of the cable, and the adhesive intensity is greatly influenced by the variables of welding time and welding pressure. Also when the welding time and welding time and welding pressure increase as the cross-sectional areas of the cable increase the welding result in gained exactly.

• Magazine of the Korean Society of Agricultural Engineers
• /
• v.36 no.4
• /
• pp.56-63
• /
• 1994

The nondimensional differential equations governing the buckling loads of tapered columns and its houndarv conditions are derived, in which the effects of shear deformations are included. These equations are solved numerically using a numerical integration technique and a bracketing method to obtain the buckling loads of columns. Four types of cross-sectional shape with clamped-free end constraint are used in the numerical examples. The parametric studies of shear deformation effects on the buckling loads such as cross-sectional shape factor, shear coefficient, ratio of modulus of elasticity, slenderness ratio and section ratio are reported in tables and figures.

• Computers and Concrete
• /
• v.17 no.2
• /
• pp.281-294
• /
• 2016

The increased awareness of electromagnetic wave hazards has prompted studies on electromagnetic shielding using conductive materials in the construction industry. Previous studies have explored the effects of the types of conductive materials and their mix proportions on the electromagnetic shielding performance; however, there has been insufficient research on the effect of the geometry of the conductive materials on the electromagnetic shielding performance. Therefore, in this study, the dependence of the electromagnetic shielding performance on the cross-sectional geometry, diameter and length of fibers was investigated. The results showed that the electromagnetic shielding performance improved when the fiber length increased or the diameter decreased, but the effect of the cross-sectional geometry of the fibers was smaller than the effect of the fiber spacing factor.

• Journal of Nutrition and Health
• /
• v.26 no.9
• /
• pp.1085-1097
• /
• 1993

Recently, as korean eating habits have been westernized, the incidence of large intestinal disease, which has been recognized as western diseases until now, has been increasing. This study was conducted to find the association of fiber intake and large bowel function. This was a cross-sectional survey, the data were obtained by self-administering questionnaire and study population was adults aged more than 18 years old in Seoul(N=1200). The response rate was 81.8%. The results were summarized as followed: 1) The factors associated with bowel function was sex, habits of defecation such as regularity and frequencies of defecation, fecal form, gastrointestinal diseases, psychological scores, self-assessment of physical status, exercise and alcohol drinking. 2) The association between the amount of fiber intake and bowel function was significant. This association was still significant, when the confounders such as disease of upper digestive system and alcohol drinking were controlled.

• Korean Journal of Child Studies
• /
• v.26 no.2
• /
• pp.121-134
• /
• 2005

Data were collected by peer nomination and sociometric nomination when children were in 4th grade and again two years later, Concurrent results of peer nominations were that prosocial children were more accepted while overtly/relationally aggressive children were more rejected by peers. Peer acceptance of males at Time 1 affected peer acceptance at Time 2. Peer rejection of females at Time 2 wasn't affected by overt aggression at Time 1. Cross-sectional results of social status were that rejected and controversial children showed higher levels of overt aggression than any other group. Popular children were most prosocial; rejected children were least prosocial. In the prospective view, aggressive males remained more rejected than any other group. Rejected children remained least prosocial.

• Journal of Industrial Technology
• /
• v.28 no.B
• /
• pp.239-244
• /
• 2008

We have realized the swept source optical coherence tomography(SS-OCT) by using the self-fabricated wavelength swept laser(wavelength tuning range : 80nm, line-width : 0.12nm, wavelength sweeping rate : 50Hz). In addition, we have used the dual balanced detector that could make a mirror image in OCT display suppressed. We can also fabricate the comb filter of Michelson interferometer type for fast-signal processing in OCT. Using this SS-OCT system for measuring an mirror, a 1mm-depth glass and an onion, we confirmed that the in vivo epidermal cross-sectional images for them can be obtained appropriately.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2001.04a
• /
• pp.1085-1088
• /
• 2001

The process of styrofoam pattern that has been used for material of press die pattern depends chiefly on handwork. Laser manufacturing system developed to increase precision and efficiency of process that is also able to convert the design easily. Applying the RP(rapid prototyping) concept reversely, the unnecessary part of section is vapored away by heat source of laser beam after converting 3-D CAD model into cross-sectional shape information. Laser beam is line-scanned in plane specimens to measure the depth and width of cut, surface roughness, cross-sectional shape as converting laser power, scanning speed, cutting gas pressure. With these basic data, plane surface, inclined surface, hole, outer contour trimming process is experimented and optimum condition are obtained. In plane and inclined surface experiments, 15W laser power and 50mm/s scanning speed make superior processing property and 30W, 10mm/s make processing efficiency increase in trimming process. With these results, simple patterns were manufactured and the possibility of applying laser manufacturing system to styrofoam pattern was convinced.

• Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
• /
• 2001.02a
• /
• pp.84-88
• /
• 2001

The optimum cross-sectional area Profile of gas-cooled high-temperature superconductor (HTS) current lead is analyzed to have minimum helium boil-off rate. The conventional constant area HTS lead has much higher helium consumption than the optimum HTS lead considered in this study. The optimum HTS lead has variable cross-sectional area to have constant safety factor. An analytical formula of optimum shape of lead and temperature profile are obtained. For multi-step HTS current leads, the optimum tape lengths and minimum heat dissipation rate are also formulated. The developed formulations are applied to the Bi-2223 material, and the differences between constant area, constant safety-factor, and multi-step current leads are discussed.

• Proceedings of the Korea Concrete Institute Conference
• /
• 2010.05a
• /
• pp.77-78
• /
• 2010

This study investigated the influence of concrete compressive strength for the lateral confinement of high-strength spiral reinforcement. The main test parameters were the compressive strength of concrete, the yield strength of spiral reinforcement, and cross sectional shape. A total of 48 cylindrical test specimens with circularand rectangular sections were cast and tested under monotonic concentric compression.

• Transactions of the Korean Society of Mechanical Engineers
• /
• v.10 no.1
• /
• pp.138-149
• /
• 1986

A numerical method is developed for the solution of fully developed turbulent recirculating flow whose cross-sectional area varies periodically. This enalbes the flow field analysis to be confined to a single isolated module, without involvement with the entrance region problem. This method are applied to the analysis of the turbulent flow field and heat transfer in artificially roughened annulus with repeated square rib.