• Journal of the Microelectronics and Packaging Society
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• v.22 no.4
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• pp.1-5
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• 2015

In high temperature aircraft electronics, aluminium based brazing filler is the prime choice today. Aluminium and its alloys have compatible properties like weight minimization, thermal conductivity, heat dissipation, high temperature precipitation hardening etc. suitable for the aerospace industry. However, the selection of brazing filler for high temperature electronics requires high temperature joint strength properties which is crucial for the aerospace. Thus the selection of proper brazing alloy material, the composition and brazing method play an important role in deciding the final reliability of aircraft electronic components. The composition of these aluminium alloys dependent on the addition of the various elements in the aluminium matrix. The complex shapes of aluminium structures like enclosures, heat dissipaters, chassis for electronic circuitry, in avionics are designed from numerous individual components and joined thereafter. In various aircraft applications, the poor strength caused by the casting and shrinkage defects is undesirable. In this report the effect of various additional elements on Al based alloys and brazing fillers have been discussed.

• MALSORI
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• no.65
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• pp.1-11
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• 2008

This study explored the perception of transplanted Korean prosody by NE (Native speakers of English) and NK (Native speakers of Korean) listeners. The Korean utterances of various sentence types produced by NE and NK were employed to transplant the original Korean prosody contours to the Korean utterances read by NE. Then, other NE and NK were instructed to rate the transplanted prosodic components. Results showed that the interactions between the two rater groups with the three factors (e.g., transplantation types & rater groups, sentence types & rater groups, sentence length & rater groups) turned out to be meaningful. Both rater groups preferred the combined effect of transplanted prosodic components (e.g. DP, DPI) to that of individual transplantation (e.g. I, D, P). Compared to NK, NE were more sensitive to duration change than pitch change whereas NK showed equal preference to the both. In sentence types such as De, Ex, Im, and Ta, NE perceived higher similarity than NK.

• Journal of the Korean Society for Precision Engineering
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• v.14 no.10
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• pp.44-49
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• 1997

The damping force is determined by four valves and the components which consist of the shock absorber for vehicle. In this study it is investigated the individual effects of four valves and these components on damping forces using dynamic behaviour analysis program of the shock absorber. In addition, opening of main valves are researched during compression and tension cycle due to up- down reciprocation movement of piston. We are to strictly control the properties and tolerance of componenets having important effects on the damping force. Thus we are intended to produce shock absorber of better quality.

• Journal of Microbiology and Biotechnology
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• v.23 no.6
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• pp.771-778
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• 2013

Essential oils are increasingly of interest for use as novel drugs acting as antimicrobial and antiviral agents. In the present study, we report the in vitro antiviral activities of 29 essential oils, extracted from Chinese indigenous aromatic plants, against the tobacco mosaic virus (TMV). Of these essential oils, those oils from ginger, lemon, tea tree, tangerine peel, artemisia, and lemongrass effected a more than 50% inhibition of TMV at 100 ${\mu}g/ml$. In addition, the mode of antiviral action of the active essential oils was also determined. Essential oils isolated from artemisia and lemongrass possessed potent inactivation and curative effects in vivo and had a directly passivating effect on TMV infection in a dose-dependent manner. However, all other active essential oils exhibited a moderate protective effect in vivo. The chemical constitutions of the essential oils from ginger, lemon, tea tree, tangerine peel, artemisia, and lemongrass were identified by gas chromatography and gas chromatography-mass spectrometry. The major components of these essential oils were ${\alpha}$-zingiberene (35.21%), limonene (76.25%), terpinen-4-ol (41.20%), limonene (80.95%), 1,8-cineole (27.45%), and terpinolene (10.67%). The curative effects of 10 individual compounds from the active essential oils on TMV infection were also examined in vivo. The compounds from citronellal, limonene, 1,8-cineole, and ${\alpha}$-zingiberene effected a more than 40% inhibition rate for TMV infection, and the other compounds demonstrated moderate activities at 320 ${\mu}g/ml$ in vivo. There results indicate that the essential oils isolated from artemisia and lemongrass, and the individual compound citronellal, have the potential to be used as an effective alternative for the treatment of tobacco plants infected with TMV under greenhouse conditions.

• Journal of the Korean Society of Food Culture
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• v.20 no.4
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• pp.451-458
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• 2005

For the storaging and frying stability in soybean oil, the kind of treating antioxidants were mixed tocopherol and phosphatidyl choline(PC), phosphatidyl ethanolamine(PE), phosphatidyl inpsitol(PI), phosphatidyl serine(PS), phosphatidic acid(PA), phosphatidyl glycerol(PG), treating amounts were 0.03%, 0.05%(w/w), respectively. Acid value(AV), peroxide value(POV) and oxidative stability index(OSI) were determined during storage period at $50^{\circ}C$ in soybean oil. Antioxidation effect at frying condition was determined through changes of smoke point. The antioxidation effect according to AV change was $PA>PC>PI{\geq}PG>PS{\geq}PE$, preventing effect about POV change was PA>PG>PC>PS>PE>PI and preventing effect about OSI decreasing was PI>PC>PA>PG>PS>PE. At the result, antioxidation effect of individual phospholipid components in soybean oil was appeared different result according to determination code. Determination result of preventing effect of SP decreasing according to frying at $180^{\circ}C$ during 20 hours was PA>PC>PG>PE>PI>PS. But treating effect of mixed tocopherol in preventing effect about AV, POV was not. In the case of storage at $50^{\circ}C$ in soybean oil, mixed tocopherol was affected as a kind of pro-oxidant. In OSI had some antioxidation effect, preventing effect of SP decreasing had not. Treatment of mixed tocopherol in soybean oil was undesirable as frying oil.

• Asian Journal of Atmospheric Environment
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• v.11 no.3
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• pp.176-183
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• 2017

Although it is well known that rain plays an important role in capturing air pollutants, its quantitative evaluation has not been done enough. In this study, the effect of raindrop size on pollutant scavenging was investigated by clarifying the chemical nature of individual size-resolved raindrops and their residual particles. Raindrops as a function of their size were collected using the raindrop collector devised by our oneself in previous study (Ma et al., 2000) during high atmospheric loading for $PM_{2.5}$. Elemental analyses of solid residues and individual residual particles in raindrops were subsequently analyzed by Particle Induced X-ray Emission (PIXE) and Scanning Electron Microscopy (SEM) with Energy Dispersive X-Ray Analysis (EDX), respectively. The raindrop number concentration ($m^{-2}h^{-1}$) tended to drastically decrease as the drop size goes up. Particle scavenging rate, $R_{sca.}$ (%), based on the actual measurement values were 38.7, 69.5, and 80.8% for the particles with 0.3-0.5, 0.5-1.0, and $1.0-2.0{\mu}m$ diameter, respectively. S, Ca, Si, and Al ranked relatively high concentration in raindrops, especially small ones. Most of the element showed a continuous decrease in concentration with increasing raindrop diameter. The source profile by factor analysis for the components of residual particles indicated that the rainfall plays a valuable role in scavenging natural as well as artificial particles from the dirty atmosphere.

• Korean Journal of Child Studies
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• v.35 no.2
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• pp.1-23
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• 2014

The purpose of this research was to investigate the most critical variables in the school adjustment of youth. In addition, this research assessed the impact of variables according to the categorization of individual, family, and school domains. To acquire the effect sizes, published studies between 1990 and 2012 were reviewed systematically and synthesized by meta-analysis. The major findings were as follows. First, this study identified a total of 34 variables which can have an influence on the school adjustment of youth and confirmed that 24 of those variables are significant. The most crucial variable that can influence school adjustment is that of a teacher's support. The next most important variables are self-resilience, relationships with friends, and self-efficiency. Focusing on the categorized elements, self-resilience is the most critical variable in the individual domain, the parent-child relation is the most crucial variable in the family domain, and a teacher's support is the most powerful variable in the school domain. Based on these results, this study suggested a number of the indispensable components in interventions to improve the youth's adjustment in school.

• Journal of Nutrition and Health
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• v.23 no.7
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• pp.504-512
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• 1990

In experiment 1, dietary self-selection of the 3 macronutrients, protein, fat, and carbohydrate were examined in male rats given 3 food cups of 80% carbohydrate, 80% protein, and 70% fat diets simultaneously. All the rats showed normal growth pattern and organ weight, which means they have ability to select just right kinds and amounts of nurients in order to support their growth and development. Mean values of caloric intake, body weight gain, serum lipid values and empty carcass compositions were not significantly differ between the upper and lower quartile groups of fat proportion of empty carcass compared to the lower quartile group(LF). Same feeding design was employed in experiment 2 where the effect of mild electric stress on food selection was studied. The rats in both control and electric stress group revealed a normal growth curve and organ weights. The rats in both control and electric stress group revealed a normal growth curve and organ weights. The stress group showed higher caloric intake and body weight gain than control group, but no significant effects of stress on serum and empty carcass components was found. Even though normal rats seemed to select macronutrients according to their physiolosical needs, there were individual differences in food selection whether they were exposed to stress or not. Therefore life long individual food selection pattern may have a great influence on nutritional status and chronic degenerative diseases of eldery, and on aging process.

• Journal of the Korea Safety Management & Science
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• v.13 no.4
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• pp.179-191
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• 2011

When it comes to the training program conducted by company to improve job performance ability, it would be not a investment but a waste if the training contents is not practically applied to the business accomplishment. Even though some people raise a question on the job application of postal distance training, funded by employment insurance, the study on the job application of postal distance training shows that the components of the training program have a positive effect on it and the model has 60.5% validity. Moreover, its control effect on environmental support and individual characteristics has been partially established. The study has been conducted by questioning survey with the employees who completed a postal education 3 months ago. With the result, we can find that the postal distance training benefits employees to improve their job performance abilities and expect that it continuously plays a crucial role in the field of company training through the development of high-quality training programs.

• Journal of The Korean Astronomical Society
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• v.49 no.3
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• pp.65-71
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• 2016

We obtain the first complete CCD light curves (LCs) of the contact binary AP UMi in the VRI bands and analyzed them by means of the PHOEBE code. A spotted model is applied to treat the asymmetry in the LCs. The LC morphology clearly shows the O'Connell effect and the solution shows an influence of star spots on both components. Such effect of star spots is common between the RS CVn and W UMa chromospherically active stars. Based on the obtained solution of the LCs we investigate the evolutionary state of the components and conclude that the system is a pre-intermediate contact binary (f = 0.29) with mass ratio q = 0.38, and it is an A-type W UMa system where the less massive secondary component is cooler than the more massive primary one.