• Korean Journal of Food Science and Technology
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• v.41 no.2
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• pp.167-172
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• 2009

The principal objective of this study was to determine the optimum manufacturing conditions of egg white with high foaming property for the production of angel food cakes. The egg whites were desugarized and powdered at predetermined pHs and drying temperatures. The physicochemical properties of the produced cakes were measured and sensory evaluations were conducted on a 9-point scale. The volume and textural properties of cakes produced from spray-dried egg whites did not differ from those of the cakes prepared from the control egg whites. The pH of batter and the specific gravity of foam and batter with egg white powder at pH 6.74/66.5$^{\circ}C$ did not differ from those of the control, whereas the one prepared with commercial powder lost the characteristics of cake to a significant degree. The overall acceptance scores of egg white powder of pH 6.74/66.5$^{\circ}C$ and commercial powder were 6.25 and 2.33 as compared to the control (6.42). These results indicate that the egg white powder that was desugarized, pH-adjusted to 6.74, and dried at 66.5$^{\circ}C$ might be utilized to prepare angel food cakes with the desirable physicochemical and sensory attributes.

• Journal of the Microelectronics and Packaging Society
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• v.7 no.3
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• pp.45-54
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• 2000

The effect of electropolishing far stamped leadframe on the removal of the edge burr and residual stress relief was examined. The present study showed that the electropolishing could be used for enhanced surface quality of stamped leadframes. The electropolishing was performed at the condition of 60% phosphoric acid electrolyte, 5 ampere of current and 3 cm electrode gap at $70^{\circ}C$ for 2 minutes for Alloy42 type leadframe, and $50^{\circ}C$ for 1.5 minutes for C-194 type leadframe. The FWHM values from X-ray diffraction showed that residual stress of electropolished leadframe recovered to the level of as-received raw materials and surface roughness measured by using AFM tuned out to be improved by 0.079 $\mu\textrm{m}$ and 0.014 $\mu\textrm{m}$ ($R_{rms}$) far alloy 42 and C-194 type leadframes, respectively. The plated thickness using XRF showed the improved uniformity in thickness variation by 0.4~0.5 $\mu\textrm{m}$ and grain growth, which is favorable for interface adhesion, was also observed from the bake test samples. We could certify dimensional stability of leadframe with inspection by means of 3D-topography and hardness measurements.

• Journal of the Society of Naval Architects of Korea
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• v.29 no.1
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• pp.173-190
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• 1992

Considerable number of offshore platforms have been built in Korean shipyards ever since 1976. Unlike for the cases of building ships, however, negligible efforts have been made to establish planning methodology for building onshore platforms. Severe congestion has been shown in the processes of assemblying modules of platforms. The module which is the upper part of a platform is a steel structure accommodating various types of outfittings and machinaries. The production planned without proper consideration on allocating work loads by trade used to show severe interferences among trades of workers and resulted in delayed completion. In this paper, a method of planning module assembly in consideration of leveling work loads by trade is discussed. A system of planning has been formulated and tested on a exampled case of producing a mix of 72 modules. The test showed a possibility of saving 31% of manpower and trimming 11% of through put time.

• Transactions of the Korean Society of Mechanical Engineers
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• v.16 no.6
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• pp.1121-1140
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• 1992

In metal cutting the shape of generated chip varies according to cutting conditions, characteristics of workpiece and geometry of cutting tool. The best surface roughness of machined workpiece is obtained when generating flow type contrinuous chip. If the generated chip is not broken, that is not only tangled workpiece and cutting tool, but also may give damage on the machined surface of workpiece or danger for a operator. The flow type continuous chip may bring the low productivity in high speed any heavy cutting, automatic machining process and non-human factory. There are two type of chip break process ; controlling cutting condition and using chip breaker. In present study we carried out the experiment on new type chip breaker compared with conventional type and proved the efficiency of a new type and showed the chip break condition to be applied in actual metal cutting. In the experiment SM 20 C as a workpiece material and WC as a tool material were used and cutting speed of 30-150m/min, feed of 0.071-0.210mm/rev and depth of cut of 1mm were applied as cutting condition. The results of the experiment are as follows : (1) The mechanism of chip curl can be explained more clearly by plastic flow of workpiece material and moment of shearing force. (2) The most effective radius of curled chip and flat distance from cutting edge is 2.0-2.5mm and 1.5mm in both types. (3) The effective inclination angle of chip break surface and side cutting edge angle are 30.deg.- 45.deg. and 20.deg. in conventional type, while the radius of arc surface, lower arc angle A, upper arc angle B and side cutting edge angle are 3mm, 20.deg.- 45.deg., 0.deg.- 45.deg. and 10.deg.- 20.deg. in new type. (4) The probability to be obtained 100% chip breaking ratio is much higher in new type than in conventional type.

• Korean Journal of Materials Research
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• v.9 no.11
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• pp.1049-1054
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• 1999

Two-step growth method is suggested to enhance the alignment of highly oriented diamond films. (100) Si wafers are pretreated with negative biasing of - 200 V at $850^{\circ}C$ for 20 min with 4 % methane in hydrogen plasma. The pretreated wafers are grown under the lst-step growth conditions(2 % CH$_4$ in H$_2$, $810^{\circ}C$) from 2 hr to 35 hr, in order to obtain <100> textured films. The 2nd-step growth(2 % CH$_4$ in H$_2$, $850^{\circ}C$) is carried out to make diamond films having (100) growth planes, which are parallel to the substrate. The alignment of the films after the 1st-step growth, has been analyzed by {111} X-ray pole figure, which is improved abruptly with increasing film thickness. However, the pyramidal surface morphology is inevitable. These morphology is flattened after the 2nd-step growth by developing the (100) facets parallel to the substrate. The alignment of the highly oriented textured films after the two-step growth depends on the thickness of the 1st-step growth film.

• Journal of the Korean Geotechnical Society
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• v.21 no.5
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• pp.93-101
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• 2005

The formation of slopes is unavoidable under the special circumstance of Korea where $7%$ of the whole area are composed of mountains and civil engineering projects such as road and site developments are increasing with industrial development and horizontal expansions of urban area. Stability of slopes is one of quite important issues under special meteorological characteristics that over two-thirds of annual average rainfall is concentrated in summer season and the localized torrential downpour is getting more frequent recently. As a result of these circumstances, partial slope failures by debris flow of the high water content soils occur frequently in cut soil slopes. In this case of debris flow slope failure, slope declination method is selected fur the stable recovery because it is impossible to recover entirely by existing recovery methods. Seeding or special grass planting methods are followed separately without exception. The method by which entire recover with bigger stability ratio would be possible and grass planting work would be done simultaneously is developed. For debris flow failure slopes, this study secured the safety of slopes by preventing the inflow of rainwater and scour using geosynthetics-reinforced embankment, and created nature-friendly slopes by planting trees on the slopes.

• Korean Journal of Agricultural Science
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• v.19 no.2
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• pp.153-160
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• 1992

To investigate the potential of paper mill sludge and briquet ash as cultural media in turfgrass, zoysiagrass was grown in the mixtures prepared with paper mill sludge and briquet ash. The mixtures were consisted of sludge and briquet ash in the ratio by volume 3:1, 2:1, 1:1, 1:2, and 1:3 in the order. To compare the growth responses, some plants were grown in the medium containing sand(3), field soil(1) and peatmoss (1) by volume anti regarded as control. 1. Activated sludge mixed with sand increased plant height, fresh weight, and dry weight more than 1.5-2.0 times compared to those of the control. The highest plant growth was shown in mixtures containing 67% activated sludge. 2. Plant density per $100cm^2$ and chlorophyll content were higher in all mixtures containing activated sludge than control. 3. The growth of zoysiagrass was reduced along with the increase of non-activated sludge ratio, but no difference was found in chlorophyll content. 4. Plant height, fresh weight and dry weight were greater in activated sludge combined with sand compared to the briquet ash mixtures, but the difference of shoot density between two mixtures was not shown. 5. Even though non-activated sludge appeared not to be appropriate to the growth of seedlings, the number of tillers of plant propagated with rhizome was more increased compared to control when briquet ash content was less than 75%.

• Journal of the Korean association of regional geographers
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• v.15 no.1
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• pp.1-15
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• 2009

This study aims to provide preliminary data needed for establishing policies on the environment and disasters of Goryeong county. The main results are as follows. First, the present master plan of the region does not reflect local socio-economic and environmental conditions and the local people's opinion. Second, The air conditions of Gyeongbuk province and Goryeong county are within the permitted limit of air pollution of Korea. Third, the analysis of water pollution index in Nakdong river system shows improvement of water quality in both Andong and Goryeong. Fourth, the conditions of waste collection and disposal are improved in both Gyeongbuk province and Goryeong county. Fifth, in case of environmental pollutant emitting facilities of Gyeongbuk province, the proportion of 1st to 4th grade(relatively much more environmental pollutant emitting quantity than 5th grade) tends to be increasing. Sixth, environmental pollutant emitting facilities of Goryeong county are remarkably increasing in Dasan, Gaegin, Ssangrim, involving industrial complex. Finally, in case of disasters, it is relatively stable in Yecheon, Gumi, Uiseong, Yeongju and Cheongdo, while relatively unstable in Seongju, Gunwi, Yeongcheon, Chilgok, Mungyeong, Bonghwa and Goryeong.

• Journal of Conservation Science
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• v.31 no.1
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• pp.1-11
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• 2015

Seated Amitabha Triad at Muwisa Temple (Treasure No. 1312) had been known as wooden Buddha statue, but a precise safety inspection revealed that the statue is terracotta Buddha statue made with clay. The clay layer of Amitabha Triad was conserved due to its severe damage. In this study, experiments were conducted to produce the most appropriate filler for the conservation treatment of the seated Amitabha Triad. Mixed clay samples with various ratios were produced and surface hardening state, crack, color change, and shrinkage of the samples during dry process were measured. Loess, fine sand powder, and cotton were used to produce the mixed clay for the filler with six different ratios and then 12 different concentration glues made with glutinous rice glue, Pachymeniopsis Elliptica glue, and animal glue were added as adhesives. Total 72 types of samples were prepared and comparative study was conducted. As a result, when the mixed clay contains 2.5% cotton compared to the weight per cent of loess and fine sand powder and also loess and fine sand in the mixed clay have a 15:1 ratio, the mixed clay had the lowest shrinkage. Animal glue is considered as an appropriate glue since it had small color change, low physical property change and shringkage. Therefore, mixed clay (loess:fine sand=15:1) mixed with 15ml animal glue is likely to be a suitable filler for conservation treatment of the seated amitabha triad at the Muwisa Temple.

• Restorative Dentistry and Endodontics
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• v.30 no.1
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• pp.22-30
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• 2005

The purpose of this study was to compare the effect of surface sealing materials on microleakage and surface roughness in Class V composite restorations. Twenty five standardized Class V cavity preparations were made on the facial surface of human premolars and were randomly assigned to 5 groups. The teeth were restored with Z-250 after applying Single Bond. Following 7 days storage in distilled water at $37^{\circ}C$, the restorations were sealed as following systems : No sealing ; Single Bond Adhesive ; Biscover ; Fortify ; Optiguard. Then, toothbrush abrasion test was conducted using a wear testing machine. Surface roughness was measured by means of profilometer before and after toothbrushing and the results were statistically analysed by using a paired t-test and ANOVA. The bonded interfaces and the changes of surface roughness were examined by SEM. For microleakage test, specimens were stained in a $2\%$ methylene blue solution, then longitudinally sectioned and analyzed for leakage at occlusal and cervical interfaces using stereomicroscope. The results were statistically analysed by using a Kruskal-Wallis and Mann-Whitney U test. Surface roughness was increasing in all groups after toothbrushing, but no statistically significant differences. In SEM observation, surface sealant was partially retained and partially detached in bonded interfaces. Especially, microgap was identified in cervical margins. In microleakage test, there was better seal in the enamel region and a significant difference between groups at occlusal margin. Control group and Single Bond group had significantly better marginal seal at enamel margin than cervical margin.