• Journal of Technologic Dentistry
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• v.19 no.1
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• pp.21-35
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• 1997

The Ag-Pd-Cu alloys containing a small amount of Au is commonly used for dental purposes, because this alloy is cheaper than Au-base alloys for clinical use. However, the most important characteristic of this alloy is age-hardenability, which is not exhibited by other Ag-base dental alloys. The specimens used were Ag-20Pd-20Cu ternary alloy and Au addition alloy. These alloys were melted and casted by induction electic furace and centrifugal casting machine in Ar atmoshpere. These specimens were solution treated for 2hr at $800^{\circ}C$ and were then quenched into iced water, and aged at $350{\sim}550^{\circ}C$ Age-hardening characteristics of the small Au-containing Ag-pPd-Cu dental alloys were investigated by means of hardness testing, X-ray diffraction and electron microscope observations, electrical resistance, differential scanning calorimetric, emergy dispersed spectra and electron probe microanalysis. Principal results are as follows : Hardening occured in two stages, I. e., stage I in low temperature and stage II in high temperature regions, during continuous aging. The case of hardening in stage I was due to the formation of the Llo type face centered tetragonal PdCu-ordered phase in the grain interior and hardening in stage I was affedted by the Cu concentration. In stage II, decomposition of the $\alpha$ solid solution to a PdCu ordered phase(L1o type) and an Agrich ${\alpha}2$ phase occurred and a discontiunous precipitation occurred at the grain boundary. Form the electron microscope study, it was concluded that the cause of age-hardening in this alloy is the precipitation of the PdCu ordered phase, which has AuCu I type face-centered tetragonal structure. Precipitation procedure was ${\alpha}\to{\alpha}+{\alpha}2+PdCu\to{\alpha}1+{\alpha}2+PdCu$ at Pd/Cu = 1 Ag-Pd-Cu alloy is more effective dental alloy as ageing treatment and is suitable to isothermal ageing at $450^{\circ}C$.

• The Journal of Korean Academy of Prosthodontics
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• v.43 no.2
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• pp.232-247
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• 2005

Purpose. The purposes of this investigation were to discover the possibility of clinical application in the areas of dental implants and bone grafts by investigating the bone formation histologically around specimen which was depending on the intensity of magnetic field of neodymium magnet inside of the specimens. Material and method. 1. Measurement of magnetic intensity - placed the magnet inside of the specimen, and measured the intensity of magnetic field around the 1st thread and 3rd thread of specimen 20 times by using a Gaussmeter(Kanetec Co., Japan). 2. Surgical Procedure - Male rabbit was anesthetised by constant amount of Ketamine (0.25ml/kg) and Rompun (0.25ml/kg). After incising the flat part of tibia, and planted the specimens of titanium implant, control group was stitched without magnet, while experimental groups were placed a magnedisc 500(Aichi Steel Co., Japan) or magnedisc 800(Aichi Steel Co., Japan) into it, fixed by pattern resin and stitched. 3. Management after the surgery - In order to prevent it from the infection of bacteria and for antiinflammation, Gentamycin and Ketopro were injected during 1 week from operation day, and dressed with potadine. 4. Preparation of histomorphometric analysis - At 2, 4 and 8 weeks after the surgery, the animals were sacrificed by excessed Ketamine, and then, specimens were obtained including the operated part and some parts of tibia, and fixed it to 10% of PBS buffer solution. After embedding specimens in Technovit 1200 and B.P solution, made a H-E stain. Samples width was 75$\mu$m . In histological findings through the optical microscope and using Kappa image base program(Olympus Co. Japan), the bone contact ratio and bone area ratio of each parts of specimens were measured and analyzed. 5. Statistical analysis - Statistical analysis was accomplished with Mann Whitney U-test. Results and conclusion. 1. In histomorphometric findings, increased new bone formation was shown in both control & experimental groups through the experiment performed for 2, 4 & 8 weeks. After 4 weeks, more osteoblasts and osteoclasts with significant bone remodeling were shown in experimental groups. 2. In histomorphometric analysis, the bone contact ratios were 38.5% for experimental group 1, 29.5% for experimental group 2 and 11.9% for control group. Experimental groups were higher than control group(p<0.05) (Fig. 6, Table IV). The bone area ratios were 60.9% for experimental group 2, 46.4% for experimental group 1 and 36.0% for control group. There was no significantly statistical difference between experimental groups and control group(p<0.05) (Fig. 8, Table VII) 3. In comparision of the bone contact ratios at each measurement sites according to magnetic intensity, experimental group 2(5.6mT) was higher than control group at the 1st thread (p<0.05) and experimental group 1 (1.8mT) was higher than control group at the 3rd thread(p<0.05) (Fig. 7, Table V, VI). 4. In comparision of the bone area ratios at each measurement sites according to magnetic intensity, experimental group 2(5.6mT) was higher than control group and experimental group 1 (4.0mT) at the 1st thread(p<0.1) and experimental group 2(4.4mT) was higher than experimental group 1 (1.8mT) at the 3rd thread(p<0.1) (Fig. 9, Table IX, X). Experiment group 2 was largest, followed by experiment group l and control group at the 3rd thread of implant. There was a significant difference at the 1st thread of control group & experiment group 2, and at 1st thread & 3rd thread of experiment group 1 & 2, and not at control group experiment group 1.(p<0.1)

• Culinary science and hospitality research
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• v.18 no.5
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• pp.267-278
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• 2012

The purpose of this study was to investigate the quality characteristics of Sulgidduck made with commercial dry rice powder, providing an optimal milk ratio and soaking time for dry powder in water to make Sulgidduck using dry rice powder. The Sulgidduk samples with dry rice powder were prepared with two soaking times (0, 30 min) and different amounts of milk (0, 20, 40, 60%), and analyzed for moisture content, Hunter's color value, texture characteristics and sensory evaluation. The moisture content of the samples ranged from 36.37% to 39.80% and the highest moisture quantity was showed in the group with 20% of milk and 30min of soaking time(SM20). The L-value was the highest in the group with 20% of milk and 0min of soaking time(M20). The b-value was increased with the amount of milk and soaking time increased, showing the highest in the group with 60% of milk and 30min of soaking time(SM60). TPA showed that SM20 had the lowest hardness and the highest adhesiveness. Chewiness, gumminess and cohesiveness were the highest in the group with 60% of milk and 0min of soaking time(M60). Based on quantitative descriptive sensory evaluations, the score of white color and moistness was showed high in the group with 0% of milk and 0min of soaking time(M0), and white powder on the surface was shown the most in the group with 20% of milk and 30min of soaking time(SM20). The score of moistness, springiness and chewiness were highest in the group with 20% of milk and 0min of soaking time(M20). Sulgidduk made with 20% of milk and 0min of soaking time(M20) was the most preferable in color, flavor, taste, and overall acceptability.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.3
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• pp.333-341
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• 2008

The objective of this study was to investigate the physical characteristics of sourdough starter containing red koji rice (SD1: 0%, SD2: 10%, SD3: 20% and SD4: 40%) and to compare the quality characteristics of sourdough breads containing 10% red koji rice powder with those of sourdough bread containing with vollsauer powder (VPB) and white wheat bread (WWB) prepared with starter SD1. The activity of ${\beta}$-amylase increased with increasing amount of red koji rice. Organic acids of sourdough starter with red koji rice (SD2, SD3 and SD4) were higher than that of sourdough starter SD1. The peak time, peak value width of tail, pH, and L value were high in WWB, while the proofing power and a and b values of WWB were lower than those of VPB and sourdough bread containing SD1 (SPB1), SD2 (SPB2), SD3 (SPB3), or SD4 (SPB4). The lowest pH, baking loss, and specific volume were observed with the VPB. The baking loss of SPB4 (sourdough bread containing SD4) was the highest (13.01%). Overall, hardness and springiness were low in sourdough bread containing red koji rice powder, whereas sourness and off-flavor were higher than in VPB. Results of specific volumes, hardness and sensory evaluation indicated that the addition of 10% red koji rice powder to sourdough starter can improve the quality characteristics of the sourdough bread.

• Journal of the East Asian Society of Dietary Life
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• v.12 no.6
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• pp.536-546
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• 2002

The purpose of this study was to determine the degree of job satisfaction of school food service employees in the Daegu and Kyoungbuk area and to compare their job satisfaction among 3 types of school foodservice systems. Questionnaires were mailed to 49 elementary schools and collected from 49 dieticians and 201 employees. The survey form was developed by analyzing the Job Descriptive Index(JDI) with the five facets of a job: the work itself, promotion pay, supervision and colleagues. Statistical analysis used in this study were fi:equency, mean, $\chi$$^2$-test, t-test and one-way ANOVA. The average JDI scores for dieticians and foodservice employees were 127.31 $\pm$ 24.51 and 136.78 $\pm$ 19.18, respectively. The foodservice workers surveyed in this study were found to be more satisfied with the work itself, the supervision and the colleagues than with the pay and the promotion. While dieticians were more satisfied with the promotion and salary, foodservice employees were more satisfied with work salary, and colleagues. The foodservice worker's demographic variables including age, education, work experience, school type and job type were significantly related to the level of job satisfaction.

• Journal of Fisheries and Marine Sciences Education
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• v.27 no.3
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• pp.625-633
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• 2015

Olive flounder (Parlichthys olivaceus) is a large carnivorous fish that live at coastal area and shallow seas in Korea. It was good texture and clean taste because of a high collagen content and low lipid content. More than 70% of olive flounder annual production was traded alive, consequently processing food product from olive flounder is rare to be towed. This study was conducted to investigate the best method of olive flounder cutlet processing. Clean fillet (headless, skinless and contain no viscera part) of olive flounder were divided into 5 portion. Every 100 g of olive flounder meat was wrapped with vinyl then flatten with meat hammer. Flatten fillet then was coated with wheat flour, and seasoned with salt and pepper. These were then coated with egg wash and bread crumbs. Two different method of processing was to make this olive flounder cutlet. Cutlet-1 was fried for 1 min in olive oil, then kept in polyethylene film vacuum packaging ($20{\times}30{\times}0.05mm$) and stored at $-20^{\circ}C$ for 7 days. After 7 days the cutlet was thawed and heat up in microwave for 2 min (Sample-1). The other proup is cutlet-2, which is directly stored in polyethylene film vacuum packaging at $-20^{\circ}C$ for 7 days then thawed and fried for 1 min in olive oil (Sample-2). The factors such as pH, TBA value, amino-N, free amino acid, chemical composition, color value (L, a, b), texture profile, sensory evaluation and viable bacterial count of the olive flounder cutlet (Sample-1, Sample-2) were measured. From the result of sensory evaluation, Sample-2 showed a little high scores than Sample-1. But there was no significant differences in color, odor, taste, texture and overall acceptance between Sample-1 and Sample-2 products.

• Food Science and Preservation
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• v.18 no.4
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• pp.559-566
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• 2011

In this study, the good brewing conditions for the 24 $^{\circ}Brix$ freeze-concentrated apple wine were investigated. The four selected Saccharomyces cerevisiae strains MM10, SS89, SS812, and WW108, could ferment quickly when brewed with high sugar levels. During the fermentation, the reducing sugar contents slowly declined while the total acid in all the yeasts increased and the final alcohol content was 12-13%, a typical wine's alcohol content. The viable counts were shown to be 6-6.8 log cfu/ml. During the fermentation, the organic acid content was shown to be within the range of 2.36-3.11%, and the free sugar content, except for the SS89 and WW108 strains, was shown to consist only of sorbitol, although fructose was somewhat detected in the SS89 and WW108 strains. Methanol was not detected, or only a trace of it was detected, and the aldehyde content was 107.68-114.27 ppm. As for the fusel oil contents, a trace of propanol was detected. Isobutanol and butanol were present in 40.16-54.65 and 25.47-27.73 ppm, respectively. The isoamy1 alcohol content was shown to be the highest (108.88-217.26 ppm). The final total phenolic compounds were shown to be 0.1-0.16%. The final Hue values were shown to be 1.3-3.6, and the final intensity was 0.1-0.45. The lightness (L) was within the range of 91.78-98.51, the redness (a) was at a neutral position at red and green, and the yellowness (b) was within the range of 2.38-7.7. In the sensory evaluation, the SS812 strain was found to be the best in terms of color, the SS89 strain in terms of odor, and the WW108 strain in terms of taste. Overall, SS812 was found to be the best apple wine.

• Food Science and Preservation
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• v.21 no.4
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• pp.451-459
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• 2014

The aim of this study was to provide useful information for making guide of quality index of Korean red pepper. The results of physicochemical characteristics analysis showed the moisture content of air-dried and sun-dried red pepper were 10.38~15.60% and 9.46~17.22%, which show that 50% of the 40 samples exceeded the 13% KS moisture standards of red pepper powder. The capsaicinoids content of the air-dried and sun-dried samples were 10.85~126.39 mg% (1,627~18,958 Scoville heat unit) and 0.43~164.09 mg% (64.5~24,613.5 Scoville heat unit). A wide distribution of ASTA values was observed: 49.12~154.69 and 70.08~182.13 for air-dried and sun-dried red pepper, respectively, with 9.29~23.10% free sugar, and 0~1,050 mg% of ascorbic acid. The total viable cells of the air-dried red peppers were 2.01~6.67 log CFU/g and of sun-dried red peppers, 1.74~5.77 log CFU/g. The contamination level of yeast in the samples were 1.03~4.12 log CFU/g of the air-dried samples and 1.05~6.10 log CFU/g of the sun-dried samples. Among the foodborne pathogens, Clostridium perfringens and Bacillus cereus were detected in many red pepper samples regardless drying method. In the principal component analysis, the first (PC1) and second principal components (PC2) accounted for 56.78 % of the total variances (38.47% and 18.31%, respectively). Ascorbic acid, ASTA, color value (L, a, b) were strongly correlated with the PC1, and quality characteristics such as moisture, microorganism, sample (drying method) showed a negative correlation with the PC1.

• Food Science and Preservation
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• v.20 no.4
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• pp.554-563
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• 2013

The changes in quality properties and nutritional components for two mugworts, namely, Artemisia capillaris Thumberg Artemisiae asiaticae Nakai fermented by Bacillus strains were characterized followed by rapid pattern analysis of volatile flavor compounds through the SAW-based electronic nose sensor in the GC system. After fermentation, the pH has remarkably decreased from 6.0~6.4 to 4.6~5.1 and there has been a slight change in the total soluble solids. The L (lightness) and b (yellowness) values in the Hunter's color system significantly decreased, whilst the a (redness) value increased via fermentation. The HPLC analysis demonstrated that the total amino acids increased in quantity and the essential amino acids were higher in the A. asiaticae Nakai than in the A. capillaris Thumberg, specially with high contents of glutamic and aspartic acid. After fermentation, the monounsaturated fatty acid increased in the A. asiaticae Nakai and the polyunsaturated fatty acids increased in the A. capillaris Thumberg. While the total polyphenol contents have not been affected by fermentation, the total sugar contents have dramatically decreased. Scopoletin, which is one of the most important index components in mugworts, was highly abundant in the A. capillaris Thumberg; however, it was not detected in the A. asiaticae Nakai. Small pieces of plant tissue in the surface microstructure were found in the fermented mugworts through the use of the scanning electron microscope (SEM). Volatile flavor compounds via electronic nose showed that the intensity of several peaks has increased and additional seven flavor peaks have been produced after fermentation. The VaporPrintTM images demonstrated a notable difference in flavors between the A. asiaticae Nakai and A. capillaris Thumberg, and the fermentation enabled the mugworts to produce subtle differences in flavor.

• Food Science and Preservation
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• v.23 no.5
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• pp.623-630
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• 2016

Inappropriate storage of fresh-cut onions may result in losses of good quality. To understand storage conditions for shelf-life and quality of fresh-cut onions, The effect of packing type and storage temperature on the quality of fresh-cut onions was evaluated. Onions stored at $0^{\circ}C$ for 2 months were peeled off after removing root and shoot parts. Each three peeled onions were packed in a polyethylene film (PE, $50{\mu}m$) or in a polyethylene/polypropylene film (PE/PP, $100{\mu}m$) with vacuum treatment (70 cmHg) and stored at different temperatures (4, and $10^{\circ}C$) for 21 days. The following analyses were examined to evaluate the quality of fresh-cut onions: microbial population, surface color, titratable acidity and pH, respiration rate, and sensory quality. Fresh-cut onions stored at $4^{\circ}C$ showed less aerobic and coliform bacterial population than those stored at $10^{\circ}C$ during observation periods. Fungal populations of fresh-cut onions packed in PE film stored at $10^{\circ}C$ increased significantly after 13 days. E. coli was not detected in all treatments during whole storage periods. Surface colors of fresh-cut onions were not affected by packing type and storage temperature, however, color difference (${\Delta}E$) of fresh-cut onions in PE/PP film stored at $10^{\circ}C$ was significantly higher than those of other treatments. Titratable acidity of fresh-cut onions was not affected by packing type and storage temperature. However, pH of fresh-cut onions packed in PE film stored at $10^{\circ}C$ increased gradually over the whole storage period. Fresh-cut onions packed in PE film showed higher $CO_2$ and less $O_2$ concentrations at $10^{\circ}C$ than those at $4^{\circ}C$. The sensory quality of fresh-cut onions was significantly affected by packing type and storage temperature after 13 days. Particularly, vacuum treatment in PE/PP film showed better sensory quality than that of PE film package at the same storage temperature. It was concluded that vacuum treatment and storage at $4^{\circ}C$ could be effective to prolong the quality of fresh-cut onions up to 21 days.