• Transactions of the Korean Society of Mechanical Engineers
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• v.13 no.4
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• pp.753-763
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• 1989

The transient response of a three-dimensional straight fin of constant cross sectional area and perimeter with unequal top, bottom, left, right and tip surface convection coefficients is analyzed using separation variables and Laplace transforms when the fin base is subjected to a step change in temperature. The three-dimensional effects of fin dimensions and unequal fin surface convection coefficients on the fin performance which is expressed in terms of the heat flowrates through the fin base are investigated, and errors in one-dimensions and unequal fin surface coefficients. Typical results are represented in tabular and graphical forms.

• Microbiology and Biotechnology Letters
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• v.28 no.5
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• pp.264-269
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• 2000

This study is that of providing a fairly practical practival guide to the use of natural pigment in food industry. A strain isolated from marine resources was carried out the production of red pigment. The pigment showed UV absorption maxima at 520 and 550 nm. The color intensity in aqueous solution was fairly stable in the ranges of pH 5~8. The strain KS-97 produced a maximum yield of red pigment at$ 25^{\circ}C$ for 72 hrs with pH 7.0. The strain KS-97 was iden-tified a Bacillus sp. based on morphological and biochemical characterization such as a rod from, motility, spore for-mation, Gram positive and catalase production. The production of red pigment indicated that the strain Ks-97 utilized at thigh concentration of colloidal chitin as carbon sources obtained maximum yield of red pigment at $25^{\circ}C$ for 72 hrs. The highest production of red pigment was observed with cultivation in medium containing 20% colloi-dal chitin, 2.5g polypeptone, 2.5g yeast extract, 1.0g $KH_2$$PO_4$, 0.01g $MgSO_4$.$6H_2$O, 0.01g $ZnSO_4$, 0.01 g $MnSO_4$(per 1).

• Magazine of the Korean Society of Agricultural Engineers
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• v.13 no.4
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• pp.2439-2444
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• 1971

This experiment is conducted to see the alteration in calculation of amount of duty of water in paddy fields, by the miraculous rice TONG-IL(IR667) made its appearance to us, therefore results obtained were summarized as follow. 1. In comparison with depth of evapo-transpiration and evaporation in the evaporator, the ratio is ET/V=1.84 in clay loam and ET/V=2.00 in loam, the value is larger than any vairety. 2. Comparison by growing periods of rice plants growing period 5 and Ear for mation stage (primor stage) 6 ET/V value grow larger from 3.30 to 3.77. 3. Transpiration ratio is 260.4 in clay loam and 275.0 in loam, two value are less than 300.

• Journal of the Korean Society for Precision Engineering
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• v.12 no.9
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• pp.148-155
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• 1995

The object of this study is to achieve a gteater understanding of meterial removal process and its mechanism. In this study, some applications of finite element techniques are applied to analyze the chip formation and cutting heat generation mechanism of metal cutting. To know the effect of cutting parameters, simulations employed some independent cutting variables change, such as constitutive deformation laws of workpiece and tool material, frictional coefficients and tool-chip contact interfaces, cutting speed, tool rake angles, depth of cut and this simulations also include large elastic-plastic defor- mation, adiabetic thermal analysis. Under a usual plane strain assumption, quasi-static, thermal-mechanical coupling analysis generate detailed informations about chip formation process and cutting heat generation mechanism Some cutting parameters are affected to cutting force, plastic deformation of chip, shear plane angle, chip thickness and tool-chip contact length and reaction force on tool, cutting temperature and thermal behavior. Several aspects of the metal cutting process predicted by the finite element analysis provide information about tool shape design and optimal cutting conditions.

• Journal of the Korean Society for Precision Engineering
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• v.14 no.2
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• pp.58-65
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• 1997

Work rolls used in cold rolling mills must have outstanding wear resistance and very little plastic defor- mation. Thus, these rolls require a higher surface hardness and harding to a greater depth. To meet these requirements, the rolls, in general, have basic chemical composition of 0.7 to 1.0% carbon and 1.0 to 5.0% Cr(chromium), plus a small amounts of special elements, and are subjected to intensive water quenching and tempering at low temperature to provide a surface hardness of over 90 shore. This test results are as follows. Deflection and fracture load of 5% Cr material are than those of 3% Cr material and show flat curve from surface to subsurface. It will be clear that 5% Cr work roll has a superior resisti- bility against wear and abrasion comparing with 3% Cr work roll. The improvement of wear and abrasion in 5% Cr work roll will be achieved by the large amount of wpheroidal carbide. In grindability and polish, 5% Cr work roll will be a little inferior comparing with 3% Cr work roll.

• Journal of the Mineralogical Society of Korea
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• v.16 no.2
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• pp.161-169
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• 2003

A phase transformation study on a synthetic amorphous diopside, $(Ca,Mg)SiO_3$has been carried out up to ∼30 GPa, and ∼$1000^{\circ}C$ using a diamond anvil cell and YAG laser heating system, respectively. A starting amorphous material shows a direct transition to cubic $(Ca,Mg)SiO_3$perovskite at high pressure, which contradicts to the crystalline diopside phase transformation sequence disproportionating into mixtures of the orthorhombic$ MgSiO_3$perovskite and the cubic $CaSiO_3$perovskite phases. This discrepancy might be due to the different starting materials as well as the temperature variations at each specific experiment performed. The present phase transfor mation sequence would modify the mineralogical assemblage in the Earth transition region and the lower mantle depending upon the pressure, temperature and the oxygen partial pressure.

• Proceedings of the ESK Conference
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• 1995.10a
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• pp.208-213
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• 1995

The vehicle navigation system is developed for helping driver to retrieve driving information more easily and lastly. Navigation System informs driver many pieces of driving information - roadway structure and system, on-line traffic condition, the position of vehicle, route guidance, destination and other infor- mation service. As the style of information is diverse and the amount of information is large, driver may have mental and visual overload. The display of information can disturb the driver's attention and this can cause accidents. This state is caused by the defect of human-machine interactions. When the navigation system is designed, human factors - cognitive, judgment, operating -must be considered. The display style must be designed simply and easily, not to be obstacle of human - machine interface. In this study, outside- in view display style and inside-out view display style are compared each other. Tow factors are measured. One is cognitive factor-time of cognition on information that is displayed by screen display, cognition error rate. The other is image of screen display - subject's feeling about several styles of display, degree of subject's preference. The prototype of roadway is four kinds -Cross, T-cross and O-cross. Roadway display for test is taken from paper maps. Traffic condition display style, vehicle position display style and route guidance display style are taken from current display style. Traffic condition display style is symbol. vehicle position display style and route guidance display style are described as color and symbol. The test on screen display is implemented doing given tasks. Then the test is analyzed statistically. The result of test analysis gives the guideline to the designer for the map display of the vehicle navigation system.

• Journal of Powder Materials
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• v.9 no.6
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• pp.422-432
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• 2002

Mechanically driven decomposition of intermetallics during mechanical milling(MM 1 was investigated. This process for Fe-Ce and Fe-Sn system was studied using conventional XRD, DSC, magnetization and alternative current susceptibility measurements. Mechanical alloying and milling form products of the following composition (in sequence of increasing Gecontent): $\alpha$(${\alpha}_1$) bcc solid solution, $\alpha$+$\beta$-phase ($Fe_{2-x}Ge$), $\beta$-phase, $\beta$+FeGe(B20), FeGE(B20), FeGe(B20)+$FeGe_2$,$FeGe_2$,$FeGe_2$+Ge, Ge. Incongruently melting intermetallics $Fe_6Ge_5$ and $Fe_2Ge_3$ decompose under milling. $Fe_6Ge_5$ produces mixture of $\hat{a}$-phase and FeGe(B20), $Fe_2Ge_3$ produces mixture of FeGe(B20) and $FeGe_2$ phases. These facts are in good agreement with the model that implies local melting as a mechanism of new phase for-mation during medchanical alloying. Stability of FeGe(B20) phase, which is also incongruently melting compound, is explained as a result of highest density of this phase in Fe-Ge system. Under mechanical milling (MM) in planetary ball mill, FeSn intermetallic decomposes with formation $Fe_5Sn_3$ and $FeSn_2$ phases, which have the biggest density among the phases of Fe-Sn system. If decomposition degree of FeSn is relatively small(<60%), milled powder shows superparamagnetic behavior at room temperature. For this case, magnetization curves can be fitted by superposition of two Langevin functions. particle sizes for ferromagnetic $Fe_5Sn_3$ phase determined from fitting parameters are in good agreement with crystalline sizes determined from XRD data and remiain approximately chageless during MM. The decomposition of FeSn is attributed to the effects of local temperature and local pressure produced by ball collisions.

• Journal of Korean Medicine Rehabilitation
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• v.24 no.2
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• pp.31-40
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• 2014

Objectives Trachelospermi caulis, known as Nak-Suk-Deung in Korea, is the dried leafy stem of Trachelospermum asiaticum var. intermedium Nakai, and climbing stems and branches of Trachelospermum sdisyivum var, intermedium nakai or Apocyanaceae. Trachelospermi caulis has antipyretic and analgesic activity. It has traditionally been used as a folk remedy in Korea for the treatment of various infla mMatory diseases, including rheumatoid arthritis. The purpose of this study was to evaluate the Effects of Trachelospermum caulis extract on SNP-induced infla mMatory responses in rabbit HIG-82 synovial membrane cells. Methods Anti-infla mMatory effects of the extract of Trachelospermum caulis were investigated using rabbit HIG-82 synovial membrane cells. For this study, 3-(4,5-dimethylthiazol- 2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, western blot analysis, PGE2 i mMunoassay, and NO detection were conducted. Results The aqueous extract of Trachelospermum caulis exerted cytotoxicity and suppressed PGE2 synthesis and NO production in rabbit HIG-82 synovial membrane cells. The aqueous extract of Trachelospermum caulis also inhibited the SNP-induced expressions of COX-2, iNOS, and TNF-$\alpha$ in rabbit HIG-82 synovial membrane cells. Conclusions These results showed that the extract of Trachelospermum caulis exerts the anti-infla mMatory effect by suppressing COX-2, iNOS, and TNF-$\alpha$ expressions in the synovial membrane cells.

• Korean journal of communication and information
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• v.26
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• pp.105-134
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• 2004

This longitudinal study examines changing factors readers of online newspaper on 1999 and 2004. In terms of Users and Gratification approach, this survey explore changing what is motives of online newspaper readers, using and satisfying of online news during five years. The factor analysis of Online newspaper's reading motive statements yielded three interpretable factors: 'informativeness-convenience', 'inter-activity', 'entertainment'. First, 'informativeness-convenience' on 2004 was lower than '99 in online newspaper reading motives and satisfying, but factor of 'interactivity' and 'entertainment' measured thar 2004 was higher than '99 in chat of online newspaper. A level of reading online newspaper on 2004 is lower than '99, 'people' and 'opinion' is highest reading online newspaper item. Bur that of '99 is 'top news' and 'political news'. 'Top news', 'economics' and 'infor-mation/science' is highest satisfying level of online news item on '99, but that of order changed into 'people'. 'opinion' and 'broadcasting/enter-tainments' on 2004. In conclusion, this study shows online newspaper readers perceived interactive service and entertainment factor.