• Journal of the Computational Structural Engineering Institute of Korea
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• v.17 no.4
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• pp.423-431
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• 2004

For the fracture mechanics analysis of cracks in welds of dissimilar steels, residual stress analysis and fracture analysis must be performed simultaneously. The standard definition of the J -integral leads to a path dependent value in the presence of a residual stress field. And unlike cracks in homogeneous materials, a bimaterial interface crack always induces both opening and shearing modes of stress in the vicinity of the crack tip. Therefore, it is necessary to develope a path independent J-integral definition for a crack in a residual stress field generated by welding of dissimilar steels. This paper addresses the modification of the Rice-J-integral to produce a path independent J -integral when residual stresses due to welding of dissimilar steels and external forces are present. The residual stress problem is treated as an initial strain problem and the J-integral proposed for this class of problems is used. And a program which can evaluate the J -integral for a crack in a weld of dissimialr steels is developed using proposed J integral definition.

• Journal of Surface Science and Engineering
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• v.40 no.2
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• pp.91-97
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• 2007

In this study we investigated the oxygen effect on the nucleation and its residual stress during unbalanced magnetron sputtering. Up to 0.5% in oxygen flow rate, cubic phase (c-BN) was dominated with extremely small fraction of Hexagonal phase (h-BN) of increasing trend with oxygen concentration, whereas hexagonal phase is dominated beyond 0.75% flow rate. Interestingly, the residual stress in cubic-phase-dominated films was substantially reduced with small amount of oxygen (${\sim}0.5%$) down to a low value comparable to the h-BN case. This may be because oxygen atoms break B-N $sp^3$ bonds and make B-O bonds more favorably, increasing $sp^2$ bonds preference, as revealed by FTIR and NEXAFS. It was confirmed by experimental facts that the threshold bias voltage for nucleation and growth of cubic phase were increased from -55 V to -70 V and from -50 V to -60 V respectively. The reduction of residual stress in O-added c-BN films is seemingly resulting from the microstructure of the films. The oxygen tends to increase slightly the amount of h-BN phase in the grain boundary of c-BN and the soft h-BN phase of 3D network including surrounding nano grains of cubic phase may relax the residual stress of cubic phase.

• Journal of the Korean GEO-environmental Society
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• v.6 no.1
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• pp.45-51
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• 2005

The distribution of shaft resistance is measured by the static load test with the strain gauge or stress gauge, so that the long-term load distribution must be considered for the pile design. However, the measurement by strain gauge generally assumes the 'zero reading', which is the reading taken at 'zero time' with 'zero' load and the residual stress, which is the negative skin friction(or the negative shaft resistance) caused by the pile construction, is neglected. Therefore, the measured value by strain gauge is different from the true load-distribution because residual stresses were neglected. In this study, the three drilled shafts were constructed, and the strain measurements were carried out just after shaft construction. As a result of this study, it is shown that the true load-distribution of drilled shaft is quite different with known load distribution and the true load-distribution of drilled shaft changed from the negative skin friction to the positive skin according to the load increment.

• Journal of the Institute of Electronics and Information Engineers
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• v.52 no.6
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• pp.79-84
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• 2015

In a distribution of digital image, there is a serious problem that is a distribution of the altered image by a forger. For the problem solution, this paper proposes a median filtering (MF) image forensic decision algorithm using a feature vector according to the pixel value's gradients. In the proposed algorithm, AR (Autoregressive) coefficients are computed from pixel value' gradients of original image then 1th~6th order coefficients to be six feature vector. And the reconstructed image is produced by the solution of Poisson's equation with the gradients. From the difference image between original and its reconstructed image, four feature vector (Average value, Max. value and the coordinate i,j of Max. value) is extracted. Subsequently, Two kinds of the feature vector combined to 10 Dim. feature vector that is used in the learning of a SVM (Support Vector Machine) classification for MF (Median Filtering) detector of the altered image. On the proposed algorithm of the median filtering detection, compare to MFR (Median Filter Residual) scheme that had the same 10 Dim. feature vectors, the performance is excellent at Unaltered, Averaging filtering ($3{\times}3$) and JPEG (QF=90) images, and less at Gaussian filtering ($3{\times}3$) image. However, in the measured performances of all items, AUC (Area Under Curve) by the sensitivity and 1-specificity is approached to 1. Thus, it is confirmed that the grade evaluation of the proposed algorithm is 'Excellent (A)'.

• Korean journal of food and cookery science
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• v.21 no.1 s.85
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• pp.33-39
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• 2005

The present study was carried out to develop sausage using Leuconostoc citreum which was isolated from Kimchi. Leuconostoc citreum was added to sausage at three concentrations of 1, 3 and $5\%$, and was stored at $10^{\circ}C$ for 40 days. The pH of the sausage containing Leuconostoc citreum was similar to the control group. The TBA value of the group containing Leuconostoc citreum was lower than the control group. However, the TBA value of the control group steadily increased after 10 days of storage, and there were only minor changes in the groups containing Leuconsostoc citreum. In addition, the TBA value of the sausages employed for the present study was either 0.46MA mg/kg or less than that over the entire period of storage. The residual nitrite value was 47.1 ppm at the beginning of the storage in the control group and was 32.5, 32.2 and 30.9 ppm in the groups containing Leuconostoc citreum. The sausages with TBA values higher than 70 ppm are not permitted in Korea. With regards totexture characteristics, it was observed the hardness was lower in the groups containing Leuconostoc ctireum than in the control group while springiness was almost the same in both the groups, but the group containing $1\%$ Leuconostoc citreum showed the best springiness. Both gumminess and brittleness were lower in the groups containing Leuconostoc citreumthan than in the control group. It was inferred that with an increase in the concentration of Leuconostoc citreum there was a decrease in the value of gumminess and brittleness. The results of the sensory evaluation were generally better in the groups containing Leuconostoc citreum than the control group. The sausage containing $3\%$ Leuconostoc citreum obtained the most excellent scores.

• Journal of Korean Society for Quality Management
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• v.20 no.1
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• pp.118-125
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• 1992

Studies upto date for estimating the reliability by means of one accarate value contain risks of many erroneous options. The objective of this paper is to presents a fault tree analueis model on the basis of the membership functions of trape Zoidal fuzzy number after imposing an interval of Confidence on the residual possibility theory. The results from the model Show that the value of Stability was reliable.

• Food Science of Animal Resources
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• v.29 no.5
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• pp.612-618
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• 2009

The objective of this study was to determine the antioxidant and antimicrobial effects of garlic juice and onion juice in emulsified sausage during cold storage. The sausages were into five groups: control, 1% garlic juice (T1), 3% garlic juice (T2), 1% onion juice (T3), and 3% onion juice (T4). Each sausage type was tested in triplicate and assigned to one of four storage periods: 0, 7, 14 and 21 days. As storage time increased, the presence of garlic juice and onion juice resulted in decreased pH, residual nitrite value, and increased peroxide value, TBARS (thiobarbituric acid reactive substance) values, and total plate counts. The pH value, peroxide value, TBARS, residual nitrite and total plate counts were significantly decreased by the addition of garlic and onion juice relative to the control (p<0.05). Especially, T2 was significantly (p<0.05) more effective in delaying lipid oxidation compared to the other treatment groups. However, no significant difference (p<0.05) was found in total plate counts among all the formulations on day 0. Also, the use of garlic juice resulted in much better antioxidant and antimicrobial effects than the use of onion juice and the control. In conclusion, this study demonstrates that the addition of 3% garlic juice (T2) to emulsified sausages tended to improve antioxidative and antimicrobial effects during storage relative to the other treatment groups.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.24 no.3
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• pp.149-158
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• 2012

This study analyzed cross-sectional variations in residual current and strengths of stratification by observing cross-sectional velocity and salinity during spring tide and neap tide, respectively, for continuous 13-hour periods at 2 observation lines at northern and southern end of Seokmo Channel, which is located west of Ganghwado. Salinity distribution of channel depends on not only neap and spring tide but also impact of salinity. The residual current component was obtained by removing $M_2$ and $M_4$ tidal components that were extracted using the least squares method on 13-hour velocity component. Cross-section of residual velocity at northern and southern end of Seokmo Channel exhibited southward residual components at channel's surface layer, but northward residual current was observed at channel's bottom layer, clearly showing a 2-layer tidal circulation between surface and bottom layers. The variation in location of appearing northward residual current according to changes in spring and neap tidal cycle and its correlation with stratification were analyzed using the Richardson number and Simpsonhunter index. At northern and southern end of Seokmo Channel, northward residual current appears in the location where Richardson number is large, Simpson-hunter index appears as a value greater than 4.

• Food Science of Animal Resources
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• v.23 no.4
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• pp.299-308
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• 2003

Quality characteristics of sausage added with green tea powder was studied to investigate the substitutive effect of green tea for nitrite. Residual nitrite, thiobarbituric acid reactive substances(TBARS) and volatile basic nitrogen(VBN) contents of 9 different sausages prepared with 3 levels of nitrite(50, 100 or 150 ppm) and 3 levels of green tea(0, 0.5 or 1％) were measured during storage at l0$^{\circ}C$ for 6 weeks or 20$^{\circ}C$ for 14 days. Proximate compositions of the sausage were not affected by the addition level of green tea or nitrite. The lightness(L value) and redness(a value) of sausage decreased, while yellowness(b value) increased, with the addition of green tea powder. Residual nitrite content was lower in sausages containing green tea when prepared with same amount of nitrite, showing the addition of green tea powder has a beneficial effect on reducing the residual nitrite content in sausage. TBARS and VBN contents were lower in sausages with nitrite and green tea than those with nitrite alone. The TBARS and VBN lowering effects of green tea were higher in sausages prepared with low level of nitrite than those prepared with high amount of nitrite. The results suggest that the addition of green tea powder may reduce the residual nitrite content of sausage, and the use of green tea may also cut down the use of nitrite in the production of pork sausage with little deterioration in preservation.

• Textile Coloration and Finishing
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• v.34 no.2
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• pp.93-101
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• 2022

In this study, the dyeing properties of supercritical fluid dyed cotton fabrics were investigated which use two types of dyes, such as C.I. Disperse orange and C.I. Disperse red 167. Dyeing temperature, pressure and leveling time were equally applied at 130 ℃, 250 bar, and 60 minutes with reference to the related literature, and experiments were performed at concentrations of 0.04, 0.1, 0.4 and 0.8 % o.w.f with different concentrations. Dyeability was confirmed through measurement of washing fastness and color coordinate, and a calibration curve of each dye was drawn up and the absorbance of the residual dye was measured to confirm the amount of residual dye and the dye exhaustion rate at the corresponding concentration. As a result of color difference measurement, as the concentration increased, the L^* value decreased and the K/S value increased. However, as the concentration increased, the increase in K/S value decreased compared to the input amount, and this tendency was more obvious in C.I. Disperse red 167 than in C.I. Disperse orange 155. The dye exhaustion rate which was calculated by using the amount of residual dye in the pot was also C.I. Disperse orange 155 was 96.16 % and C.I. Disperse red 167 was 94.57 %. However, as the dyeing concentration increased, the dye exhaustion rate decreased, that C.I. Disperse orange was 95.33 % and C.I. Disperse red 167 was 90.63 %. As a result of the washing fastness test for both dyes, dyed samples of which concentrations were 0.4 and 0.8 % o.w.f decreased by 0.5 ~ 1.0 grade. This is predicted because the dye did not completely adhere to the amorphous region of the cotton fiber and the dye simply adsorbed. The fastness to rubbing also maintained at least grade 3-4 up to the 0.1 % o.w.f concentration, but at the concentration of 0.4 % o.w.f or higher, it fell to grade 1 or lower, showing a very poor friction fastness.