• Journal of the Institute of Electronics Engineers of Korea SP
• /
• v.41 no.3
• /
• pp.139-146
• /
• 2004

A 2D/3D complex optical system and its vision inspection algerian is proposed and implemented as a single probe system for high speed, precise vision inspection of the solder pastes. One pass un length labeling algorithm is proposed instead of the conventional two pass labeling algorithm for fast extraction of the 2D shape of the solder paste image from the recent line-scan camera as well as the conventional area-scan camera, and the optical probe path generation is also proposed for the efficient 2D/3D inspection. The Moire interferometry-based phase shift algerian and its optical system implementation is introduced, instead of the conventional laser slit-beam method, for the high precision 3D vision inspection. All of the time-critical algorithms are MMX SIMD parallel-coded for further speedup. The proposed system is implemented for simultaneous 2D/3D inspection of 10mm${\times}$10mm FOV with resolutions of 10 ${\mu}{\textrm}{m}$ for both x, y axis and 1 ${\mu}{\textrm}{m}$ for z axis. Experiments conducted on several nBs show that the 2D/3D inspection of an FOV, excluding an image capturing, results in high speed of about 0.011sec/0.01sec, respectively, after image capturing, with $\pm$1${\mu}{\textrm}{m}$ height accuracy.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.36 no.11
• /
• pp.1345-1352
• /
• 2012

This paper aims to evaluate the low-velocity impact responses and mechanical properties of balsa-wood and urethane-foam core materials and their sandwich panels, which are applied as the impact limiter of a nuclear spent fuel shipping cask. For the urethane-foam core, which is isotropic, tensile, compressive, and shear mechanical tests were conducted. For the balsa-wood core, which is orthotropic and shows different material properties in different orthogonal directions, nine mechanical properties were determined. The impact test specimens for the core material and their sandwich panel were subjected to low-velocity impact loads using an instrumented testing machine at impact energy levels of 1, 3, and 5 J. The experimental results showed that both the urethane-foam and the balsa-wood core except in the growth direction (z-direction) had a similar impact response for the energy absorbing capacity, contact force, and indentation. Furthermore, it was found that the urethane-foam core was suitable as an impact limiter material owing to its resistance to fire and low cost, and the balsa-wood core could also be strongly considered as an impact limiter material for a lightweight nuclear spent fuel shipping cask.

• Proceedings of the Korean Radioactive Waste Society Conference
• /
• 2005.11a
• /
• pp.321-331
• /
• 2005

Recently. three-dimensional models have been used for aquatic dispersion of radioactive effluents in relation to nuclear power plant siting based on the Notice No. 2003-12 'Guideline for investigating and assessing hydrological and aquatic characteristics of nuclear facility site' of the Ministry of Science and Technology (MOST) in Korea. Several nuclear power plants have been under construction or planed. which are Shin-Korl Unit 1 and 2, Shin-Wolsong Unit 1 and 2, and Shln-Ulchin Unit 1 and 2. For assessing the aquatic dispersion of radionuclides released from the above nuclear power plants, it is necessary to know the coastal currents around sites which are affected by circulation of East Sea. In this study, a three dimensional hydrodynamic model for the circulation of the East Sea of Korea has been developed as the first Phase, which Is based on the RIAMOM. The model uses the primitive equation with hydrostatic approximation, and uses Arakawa-B grid system horizontally and Z-coordinate vertically. Model domain is $126.5^{\circ}E\;to\;142.5^{\circ}E$ of east longitude and $33^{\circ}N\;and\;52^{\circ}N$ of the north latitude. The space of the horizontal grid was $1/12^{\circ}$ to longitude and latitude direction and vortical level was divided to 20. This model uses Generalized Arakawa Scheme. Slant Advection, and Mode-Splitting Method. The input data were from JODC, KNFRDI, and ECMWF. The model ing results are in fairly good agreement with schematic patterns of the surface circulation in the East Sea The local current model and aquatic dispersion model of the coastal region will be developed as the second phase. The oceanic dispersion experiments will be also tarried out by using ARGO Drifter around a nuclear pelter plant site.

• Korean Journal of Social Welfare
• /
• v.67 no.4
• /
• pp.103-126
• /
• 2015

This study is to explore how the stakeholder views the community needs in a different way in the local district of Korea. The researchers delivered the 3 independent questionnaires to the three types of the community people who are residents, social service providers, governmental officials in charge of local social services. An in-depth analysis was performed to identify the different perspectives of the stakeholder toward the community needs on the basis of the combined approach with the order ranking method and two independent sample T and Z tests. As the result, the three noticeable findings were discovered as follows: First, while the social service providers reported the community needs at the most serious level, the residents expressed the community needs at the least serious level. Second, the stakeholder showed more diverse opinions for the needs of the service activities than the community problem. Third, there was a difference among the stakeholder in the degree of consensus according to the two different analysis methods. The researchers discussed the implication of the major findings in relation to the community needs assessment, and suggested the practical recommendations to improve the activities of the community needs assessment for the community welfare planning in Korea.

• Applied Biological Chemistry
• /
• v.38 no.2
• /
• pp.111-117
• /
• 1995

In Escherichia coli, CRP forms a complex with cAMP and acts as a transcriptional regulator of many genes, including sugar metabolism operons. The E. coli MK2001, which is introduced the altered crp, is functional in the expression of lac, ara and man, in the absence of cAMP. However, the expression of mal gene is fully activated by the addition of cAMP or cGMP. The object of the study is cloning of the sfs (sugar fermentation stimulation) genes, which was involved in regulation of mal gene expression with the altered crp gene, and structural analysis and characterization of the genes at the molecular level. We have cloned 5 different E. coli genes which stimulate the maltose metabolism in a crp, cya::km (MK2001) background. Newly identified genes were designated as sfs. One of the sfs genes (pPC1), located at the 53.2 min map position on the E. coli chromosome, was further analyzed. Expression of the genes, which is involved in maltose metabolism, malQ (amylomaltase), was increased to 5.8-fold in the presence of a plasmid, pAP5, containing the subcloned sfs4 gene. The nucleotide seguence of a common 2,126 bp segment of the pPCM1 was determined and two open reading frames (ORF1 and ORF2) were detected. The ORF1 encodes the sfs4 gene and ORF2 encodes a truncated protein. Potential CRP binding site is located in the upstream of the putative promoter in the regulatory region. Expression of the cloned sfs4 gene was positively regulated by the cAMP-CRP complex.

• Nuclear Engineering and Technology
• /
• v.6 no.1
• /
• pp.14-22
• /
• 1974

Effects of anodization voltage on frequency characteristics of anodic oxide films on tantalum were analyzed based on the following impedance equatious : (equation omitted) Here $R_{f}$, $C_{f}$ and tan $\delta$$_{f}$ are equivalent series resistance in ohm, equivalent Belies capacitance in farad and dielectric loss, of anodic oxide films respectively Parameters P, $\tau$$_{ο}$, $\tau$$_{\omega}$, and Co are defined as follows: P=(d-w)/w, $\tau$$_{ο}$=$textsc{k}$$\rho$$_{ο}$, $\tau$$_{\omega}$=$textsc{k}$$\rho$$_{\omega}$, $C_{ο}$=$textsc{k}$A/d where d is the thickness of oxide film, $\omega$ is the diffusion layer thickness. $\rho$$_{ο}$ is the resistivity of oxide film at the interface of metal and the oxide, $\rho$$_{\omega}$ is the resistivity of oxide film at intrinsic region and A is the area of the film and $textsc{k}$=0.0885$\times$10$^{-12}$ $\times$dielectric constant, (in farad/cm). It was shown that dielectric loss and frequency dependence of equivalent series capacitance decrease as anodization voltage increases. This is a consequence of the fact that the thickness of diffusion layer increases a little with increasing anodization voltage whereas the total oxide thickness is proportional to the anodization voltage. The ngative deviation of measured values from tile relation, tan $\delta$$_{f}$=0.682 $\Delta$ $C_{f}$, was also discussed based on the Impedance equations given above. Here $\Delta$ $C_{f}$ is the change in capacitance between 0.1 and 1 KHZ.KHZ.Z.

• Journal of the korean academy of Pediatric Dentistry
• /
• v.33 no.2
• /
• pp.281-289
• /
• 2006

Topical fluoride application for children is a widely performed procedure in the field of Pediatric Dentistry for its dental caries prevention effects However, it is recently recognized as having some unwanted effects on several esthetic restorative materials, the author immersed glass ionomer cement, compomer and composite resin specimens in APF gel and measured the surface roughness and also, examined the specimens under the scanning eletron microscope. The followings are the results: 1. In the specimens of glass ionomer cement and compomer, APF gel 4 minute immersion group and pH cycling group show statistically significant increased surface roughness than artificial saliva immersion group (p<0.01). 2. There was no statistically significant surface roughness for composite resin in all group (p>0.05). 3. When the specimens were examined under scanning electron microscope, the surface change were in the order of glass ionomer cement, compomer, composite resin and also in the order of pH cycling group, APF gel 4 minutes immersion group, artificial saliva immersion group.

• Journal of the korean academy of Pediatric Dentistry
• /
• v.29 no.1
• /
• pp.19-29
• /
• 2002

The purpose of this study was to compare the polymerization shrinkage and the compressive strength of composite and compomer cured with two different light sources ; conventional halogen-light curing unit and recently-developed plasma arc curing unit. The 'strain gauge method' was used for determination of polymerization shrinkage and the compressive strength was measured by universal testing machine. The results of the present study can be summarized as follows: 1. Filling materials in polyethylene molds showed the initial expansion in the early phase of polymerization. This was followed by the rapid contraction in volume during the first 60 seconds and gradually diminished as curing process continued. 2. The polymerization shrinkage in tooth samples was generally lower than in the mold samples. 3. The generally lower amount of linear polymerization shrinkage was observed in compomer and plasma arc curing unit group when compared to composite and conventional curing unit. 4. The higher compressive strength values was found in composite groups regardless curing methods. The results of this study strongly support the application of plasma arc system and fluoride-containing compomer in the field of clinical pediatric dentistry claiming its effectiveness in curing the esthetic dental materials and the anticariogenic capacity.

• The Journal of Korean Society for Radiation Therapy
• /
• v.33
• /
• pp.55-62
• /
• 2021

Purpose: This study aims to contribute to the reduction of complications of breast cancer radiation therapy by analyzing skin dose differences due to Set-up error. Materials and Method: Pseudo breast was produced using a 3D printer, applied to the phantom, and images were acquired through CT. Treatment plan was carried out that the PTV, which contains 95% of the prescription dose, could be more than 95% of the volume, so that Dmax did not exceed 107% of the prescription dose. The Set-up error was evaluated by applying ±1mm/±3mm/±5mm to the X-axis, Y-axis, and Z-axis. Results: The dose-variation in skin due to Set-up error was approximately 106% to 123% compared to prescription dose, and the highest dose in skin was 49.24 Gy at 5mm Set-up error in the lateral direction of the X-axis. More than 107% of the prescription dose was the widest at 6.87 cc in skin lateral. Conclusions: If a Set-up error occurs during left breast cancer VMAT, a great difference in skin dose was shown in the lateral direction of the X-axis. If more effort is made to align the X-axis of the breast treated during CBCT registration, the dose-variation of skin will be reduced.

• The Journal of the Korea Contents Association
• /
• v.22 no.9
• /
• pp.308-321
• /
• 2022

The purpose of this study is to understand how self-esteem, shopping motivations, and shopping tendencies affect the clothing purchase behavior of the so-called "MZ generation," a cohort that includes both millenials and Generation Z and exerts significant influence in various areas. The results of this study can be summarized as follows: First, it was found that extrinsic purchase motivations (purchased made due to the influence of other people), trend-seeking shopping tendencies, and pleasure-seeking shopping tendencies had a positive and significant effect on personal needs among the sub-factors of clothing purchase behavior of the MZ generation. Second, it was found that the MZ real purchase shopping motivations, trend-seeking shopping tendencies, pleasure-seeking shopping tendencies, and convenience-seeking shopping tendencies had a positive and significant effect on actual needs among the sub-factors of clothing purchase behavior among the MZ generation. Third, it was found that social self-esteem, extrinsic purchase motivations, and convenience-seeking shopping tendencies had a positive and significant effect on clothing marketing strategies among the sub-factors of clothing purchase behavior of the MZ generation. On the other hand, personal self-esteem was found to negatively affect the marketing strategies of clothing purchase behavior. In other words, the expectation that the MZ generation would buy clothes in accordance with their individual preferences and beliefs was not supported by the findings of this study. It would appear that the beliefs and behaviors of the digitally savvy MZ generation are changed by the fashion trend-related information they readily access when purchasing clothing. From the above research results, it can be concluded that there many variables that influence the clothing purchase behavior of the MZ generation and it is thus necessary to consider this cohort a new consumer segment and establish marketing strategies accordingly.