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1.
After the remarkable increase of Internet users and broadband Internet subscribers at the end of the 20th century, the size of Korean Internet and e-commerce market steadily increased but the growth rate has been either stagnant or decreased. Trends of Korean Internet and e-commerce market are summarized in this paper the trends on Internet usage are introduced. Trends of online games, blogs and wireless Internet are introduced. The trends of Korean Internet market may have implications for China and Japan. 相似文献
2.
The concept of directional binding energy (DBE) is proposed to describe the binding energy of the crystal and the ideal direction
of the antiaction force against the surface tension, which derives the grain-boundary energy and also energy ratio (γgb/γs). It may provide a simple and lucid way to analyse the surface energy, grain-boundary energy and energy ratio from the correlative
view point. It has been found that the grain-boundary energy can be derived only from the conceptual approach of DBE, irrespective
of the dislocation model, which also makes it possible to determine the energy ratio with the misorientation angle. That is,
the energy ratio (γgb/γs) is proportional to the misorientation angle, 2 sin (k′θ/2) where k′ is a constant and θ is the misorientation angle.
This revised version was published online in November 2006 with corrections to the Cover Date. 相似文献
3.
S. Y HO 《Journal of Materials Science》1997,32(19):5155-5161
A methodology for determining the response of rocket motor materials and bondlines to thermal loadings by measuring their
dynamic mechanical properties is reported. The critical temperatures at which debonding and/or propellant cracking occur and
the number of thermal cycles required to induce failure were evaluated. These results were compared with those from instrumented
rocket motors subjected to similar thermal loadings. A model, developed for fibre reinforced composites, was applied to the
propellant-inhibitor bimaterial obtained from a rocket motor. The internal energy dissipation due to a lack of perfect adhesion
at the propellant–inhibitor interface, tan δadh, was used to give an indication of the failure mode of the bondline (i.e., adhesive failure at the interface or cohesive
failure in the propellant) and the bond adhesion parameter, C, was related to the bond strength measured by rectangular bond-in-tension
tests.
This revised version was published online in November 2006 with corrections to the Cover Date. 相似文献
4.
5.
E Prescott M Osler PK Andersen A Bjerg HO Hein K Borch-Johnsen P Lange P Schnohr J Vestbo 《Canadian Metallurgical Quarterly》1997,26(6):1214-1218
BACKGROUND: Two recent much cited publications have raised the concern that risk associated with cigarette smoking has so far been underestimated. In this study we wish to determine whether excess all-cause mortality associated with smoking has increased during the last 20-30 years in a study population representative of the general Danish population and whether any such changes relate to changes in smoking behaviour. METHODS: Pooled data from three prospective population studies conducted in Copenhagen with detailed information on smoking habits. A total of 31,194 subjects, 17,669 males and 13,525 females, initially examined between 1964 and 1992 with examinations repeated at intervals from 1-10 years, were followed until 1995 for all-cause mortality. Relative mortality risk in smokers versus never-smokers was calculated within periods of five calendar years and compared throughout the study period. RESULTS: Male smokers' exposure did not change during the study period whereas female smokers' exposure to tobacco increased in terms of age at smoking onset, quantity smoked and depth of inhalation. During follow-up 5744 males and 2900 females died. In males, death rate ratios (comparing continuous smokers with never-smokers) did not change in the study period. In females, ratios increased from 1964-1978 to 1979-1994 by a factor of 1.3 (95% confidence interval 1.0-1.8). CONCLUSIONS: In agreement with the observed changes in smoking habits, excess mortality in male smokers did not increase whereas excess mortality in female smokers increased slightly. 相似文献
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8.
J. W. PARK R.F. TESTIN P. J. VERGANO H.J. PARK C.L. WELLER 《Journal of food science》1996,61(4):766-768
The effects of various stearic-palmitic acid blend concentrations in films, storage temperatures and storage times on potato chip quality were evaluated using Response Surface Methodology. Storage temperature and time affected the quality of potato chips. The maximum storage times for acceptable potato chip quality were: 30 to 43 days, 23 to 25 days, and 11 to 12 days for storage temperatures of 15, 25 and 35°C, respectively. Results were independent of stearic-palmitic acid blend concentrations. 相似文献
9.
J.G. CHUNG J.H. LEE C.C. HO J.M. LAI Y.C. CHOU H.H. TENG C.F. HUNG S.C. HUANG 《Journal of Food Biochemistry》1996,20(4):481-490
The N-acetyltransferase activity was determined in 58 common fruits and vegetables. The assay was based on acetylation of 2-aminofluorene or p-amino-benzoic acid, followed by high pressure liquid chromatographic analysis of products and remaining nonacetylated substrate. The highest specific activities were observed in Balsam pear which contained 17.37 ± 1.45 N-acetyl aminofluorene nmole/min/mg protein and 46.27 ± 6.87 N-acetyl p-aminobenzoic acid nmole/min/mg protein. N-acetyltransferase activities within the remaining 57 foodstuffs analyzed ranged from none detected to 3.39 ± 0.72 N-acetyl aminofluorene nmole/min/mg protein and none detected to 32.45 ± 6.55 N-acetyl p-aminobenzoic acid nmole/min/mg protein. This is the first demonstration of acetyl CoA: arylamine N-acetyltransferase activity in common foodstuffs. 相似文献
10.
With greater need for treating root surface lesions, dentinal adhesives are more in demand. For successful treatment, all factors--dentin, tooth, patient and materials--must be considered. 相似文献