• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1993.10a
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• pp.291-296
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• 1993

Taking a bledes axle of rotary tiller as a example, this paper discusses influences of four loading essential factors, which are strengthened amplitude, cycle times, loading sequence and loading frequency. in fatigue life. Determination principles of above four factors and monitoring methods of fatigue damage by local strain are dealt with. The actual field testing check of farm machinery is rapidly simulated by laboratory program fatigue test can shorten the period of development and improvement of a product. In the time of in-door simulation test, damage monitoring and four loading essential factors, which are strengthened amplitude , cycle times, loading sequence and loading frequency, have to be dealt with . If these problems are solved successfully, it is possible to accelerated test speed, reduce costs and manhours, and raise accuracy of test result. However strengthening method, loading pattern and influence of loading frequency on test result have not so far been discu sed systematically, damage monitoring is even more a difficult problem. Authors have studied above problems with the object of blades axle of rotary tiller.

• Journal of Microbiology and Biotechnology
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• v.7 no.3
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• pp.209-211
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• 1997

A quantitative method for assaying bioemulsifiers in culture broth was developed and applied to cultivation of Pseudomonas aeruginosa YPJ80. SED(Standard Emulsification Dilution), an indirect measure of bioemulsifier concentration, was proposed. Production of bioemulsifier and rhamnolipid reached their maximum simultaneously. However, the bioemulsifier/rhamnolipid ratio decreased with cultivation time. This indicates the presence of another bioemulsifier other than rhamnolipid. The bioemulsifier seems to be protein-like activator which showed emulsification activity in addition to rhamnolipid.

• Journal of the Korean Applied Science and Technology
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• v.21 no.3
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• pp.238-245
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• 2004

The interaction between anion and zwitterionic surfactants was investigated by means of surface tension, NMR spectroscopy, and fluorescence studies. These systems are N-tetradecyloxymethyl-N,N-dimethyl betaine ($C_{14}$, TDB), N-octadecyloxymethyl-N,Ndimethyl betaine ($C_{18}$, ODB), and sodium dodecylethoxy sulfate (SDE). These systems show a composition dependency in micellar properties. When the molar fraction of TDB and ODB was about 0.6, the cmc values of these systems showed minima, whereas the solubilized amount of a water insoluble dye, NMR line width showed maxima. These changes comes from the intramolecular complexes formed in the mixed micelles. The complexes are due to the electrostatic interaction of oppositely charged head groups of betaine and sodium dodecylethoxy sulfate. A comparison of betaine and SDE alkyl methylene group line widths to those of n-methyl group indicates that the interior of the micelle in the restricted region is more immobile than the head group.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1997.04a
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• pp.309-313
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• 1997

(Ba$_{x}$Sr$_{l-x}$)TiO$_3$(BST) thin fi1ms with various Ba/Sr ratios were deposited on Pt(80nm)/SiO$_2$(100nm)/Si by RF magnetron sputtering. BST thin films which have x=0.6, 0.5, 0.4 were studied dielectric properties with temperature variation. The frequency was used from 100Hz to 1MHz for measuring dielectric constant. The measurement conditions of dielectric constant with Temperature Variation were 1KHz and 2$0^{\circ}C$. As a result, the dielectric constant of BST thin film was about 425 and loss factor was 0.013. Also, with increasing Temperature, the dielectric constants of BST thin films were gradually decreased.sed.

• Journal of Korean Vacuum Science & Technology
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• v.6 no.1
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• pp.8-11
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• 2002

Ni, Si and $SiO_2$ films were implanted by 350 keV B $i_{+}$ ions at room temperature with fluences of 1$\times$10$^{16}$ and 2$\times$10$^{16}$ ions/c $m^2$ The depth distributions of implanted B $i^{+}$ ions in Ni, Si and $SiO_2$ films were by investigated by Rutherford backscattering. The results show that the depth distributions of implanted B $i^{+}$ ions into Ni, Si and $SiO_2$ films have obeyed nearly Gaussian distributions. The maximum difference between experimental and calculated values is less than 18 % for mean projected range. Experimental range straggling deviated significantly from calculated value. The possible reasons are discussed.sed.d.

• The Bulletin of The Korean Astronomical Society
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• v.39 no.2
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• pp.64.1-64.1
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• 2014

We study the dust and star-formation characteristics of a nearby dwarf elliptical galaxy, NGC 855. With various archival data from ultraviolet to far-infrared, we build up the spectral energy distribution (SED) that can give us constraints on stellar populations, dust characteristics, star-formation history, etc. From GALEX and SDSS data, slightly de-centered bluer central core is confirmed, where star formation might take place. This regions is coincident with seemingly dis-integrated cores detected by Spitzer IRAC data and with bright Ha feature observed at ground-based telescope. The PACS and SPIRE data by Herschel Space Observatory show the dominant dust features at the center. Lastly, we propose necessary follow-up observations with ground-based telescopes to investigate spectral properties of NGC 855.

• The Bulletin of The Korean Astronomical Society
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• v.41 no.2
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• pp.63.1-63.1
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• 2016

We observed Ultra-Long GRB 111209A using NASA's 3m InfraRed Telescope Facility (IRTF). The observation was started around 40 min later than T0 = 07:12:08 UT of Swift's BAT, lasted for 24 min. The spectrum was extracted using Spextool package. The NIR SEDs show power law distribution indicating afterglow emission from the GRB according to the fireball model with beta ~ 1.2. Also they do not show thermal emission component compared to the SED of "Christmas burst" GRB 101225A. Because there is no other NIR data with this observation epoch, this data can be compared only with TAROT-R band. It seems NIR data has the same flare which exists in R band as an optical flare.

• Journal of the Korean Society of Food Science and Nutrition
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• v.19 no.2
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• pp.115-120
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• 1990

This study was conducted to investigate the relation of softening with the mineral compone-nts during ripening of tomato fruits. The mineral contents of Ca, K, Mg, Zn. Fe Mn and Cu and its existence form respiratory rate and hardness during ripening were evaluated. The respiratory rate of tomato fruits was decreased until 42 days after anthesis and then increased the climacteric maximum was found on 49 days after anthesis then decreased. The hardness of tomato fruits during ripening did not change greatly until 45days after anthesis then decrea-sed markedly. The major mineral components of tomato fruits were K, Ca, and Mg, Zn Fe Mn and Cu were the minor components. The contents of soluble Ca, Ma and K increased markedly and those of bound Ca and Mg decreased markedly after 45days during ripening,. However other components were not changed greatly.

• Structural Engineering and Mechanics
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• v.74 no.5
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• pp.601-609
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• 2020

In this article, the Strain Energy Density (SED) averaged over a well-defined control volume at a notch edge was applied in combination with the Equivalent Material Concept (EMC) to assess the fracture behaviors of some keyhole-notched specimens made of a High-Density Polyethylene (HDPE-PE80) material under mixed-mode loading conditions. An experimental program was performed and 54 new experimental data were totally provided. Additionally, different loading mode ratios were regarded by changing the inclination angles of the notches with respect to the applied load directions. The results obtained from the determined criteria were in good agreement with those of the experimental data.

• Bulletin of the Korean Chemical Society
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• v.23 no.9
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• pp.1253-1309
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• 2002

1,3,5-Tricyano-2,4,6-tris[2-(thiophen-2-yl)vinyl]benzene derivatives have been synthesized as a new type of octupolar nonlinear optical molecules and their linear and nonlinear optical properties were determined. The λmax values increa sed with the conjugation length and as the conjugation bridge was changed from phenyl to thienyl group. For phenyl and thiophene derivatives, the b value increased with conjugation length. In contrast, the $\beta$ values of the thiophene derivatives were much smaller than the corresponding phenyl derivatives.