• Journal of the Korean Society of Industry Convergence
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• v.10 no.3
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• pp.137-141
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• 2007

The sugar content of persimmon fruits was decreased when food-waste compost was used. Dungsi was brighter with yellow color than that of control. The Gabjubaekmok was darker than that of control with red color. It was suggested that taste of astringent was reduced because total phenol and soluble tannin contents were reduced by that compost. The vitamin C content of persimmon fruits during storage was higher than that of control. Stability of persimmon fruits by that compost and usual compost was about the same at room temperature. At low temperature, hardness of persimmon fruits was maintained for 20days. Hardness and reducing sugar contents of persimmon fruits were increased by food-waste compost. The result was shown that there was no effect on composition of persimmon fruits by food-waste compost and maintaining hardness at room temperature, but at low temperature, the composition of persimmon fruits was changed.

• Food Science and Preservation
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• v.30 no.4
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• pp.602-616
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• 2023

Fifteen types of rice collected from Kurdistan region-Iraq were investigated by principal component analysis (PCA) in terms of physical properties and cooking characteristics. The dimensions of evaluated grains correspond to 5.05-8.75 mm for length, 1.54-2.47 mm for width, and 1.37-1.95 for thickness. The equivalent diameter was in the range of 5.23-10.03 mm, and the area took 13.30-28.25 mm². The sphericity analysis values varied from 0.32 to 0.56, the aspect ratio from 0.17 to 0.39, and the volume of the grain was measured in the range from 4.48 to 17.74 mm³, hectoliter weight values were 730-820 kg/m³, and true density from 0.6 to 0.96 g/cm³. The broken grain ratio was 1.5-18.3%, thousand kernel weight corresponded to 15.88 to 22.42 g. The water uptake ratios for 30 min of soaking were increased at 60℃ compared to 30 and 45℃. The PCA was used to study the correlation of the most effective factors. Results of PCA showed that the first (PC1) and second (PC2) components retained 63.4% and 34.8% of the total variance, which PC1 was mostly related to hectoliter, broken ratio, and moisture content characteristics while PC2 was mostly concerned with hardness and true density. For cooking properties, the PC1 and PC2 retained 88.5% and 9.3% of the total variance, respectively. PC1 was mostly related to viscosity, spring value, and hardness after cooking, while PC2 was mostly concerned with spring value, hardness before cooking, and hardness after cooking.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.6
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• pp.1091-1095
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• 1997

The physicochemical properties of rice flour and textural properties of cooked rices between Chungmubyeo and Dongjinbyeo were compared. The protein contents of Chungmubyeo and Dongjinbyeo were 7.9% and 8.8%, and the crude and total lipid were 0.82%, 0.65% and 2.34%, 1.66% respectively. The amylose content was 21.1% in Chungmubyeo and 20.2% in Dongjinbyeo. The hardness of rice grain was higher in Dongjinbyeo while water absorption was higher in Chungmubyeo. The sensory evaluation of cooked rice made from Chungnubyeo was significantly higher in shininess, roasted nutty flavor, hardness and overall eating quality than that from Dongjinbyeo. The hardness of cooked rices by rheometer was increased during storage and was lower in Chungmubyeo than Dongjinbyeo.

• Journal of Environmental Health Sciences
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• v.19 no.1
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• pp.44-50
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• 1993

In order to investigate the hygienic conditions of potable water in farm area, we examined the hygienic bacteriological and chemical tests of the 159 waters in the farm areas of Kwangjugun, Namyangju-gun, Yangpyung-gun Paju-gun and Hwasung-gun.The results were as follows: 1. Of the 159 waters, the average numbers of standard plate count and coliform were 920 $\pm$ 250ml and 450 $\pm$ 380/100 ml, respectively. The average pH was 6.74 $\pm$ 0.08, KMnO$_4$ consumption 4.18 $\pm$ 0.23 mg/l, turbidity 0.74 $\pm$ 0.08 degree, NH$_3$-N 0.07 $\pm$ 0.02 mg/l, NO$_3$-N 7.76 $\pm$ 0.48 mg/l, total hardness 101.3 $\pm$ 4.7mg/l, chlorine 18.6 $\pm$ 1.3mg/l, sulfate 12.9 $\pm$ 1.0 mg/l, lead 0.036 $\pm$ 0.003 mg/l, manganese 0.017 $\pm$ 0.003 mg/l, zinc 0.064 $\pm$ 0.005 mg/l, and copper 0.010 $\pm$ 0.001 mg/l, respectively. 2. Of the 159 waters, 84 samples (52.8%) were over 100 per ml of SPC or detected coliform per 100 ml water and 63 samples (39.6%) exceed over physicochemical limited criteria for potable water. NO$_3$-N was the primary item among excess contents of potable water in farm areas. 3. The contents of total hardness, chlorine and NO$_3$-N in Hwasung-gun were higher than those in the other regions, but the numbers of SPC and coliform in Yangpyung-gun and Namyangjugun were higher than those in the other regions. 4. The correlationships among many items were highly significant (SPC, Coliform, KMnO$_4$ consumption NH$_4$-N, NO$_3$-N, KMnO$_4$, Total hardness, Chlorine, Sulfate).

• Journal of the Korean Society of Food Culture
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• v.35 no.6
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• pp.577-581
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• 2020

This study examined the physicochemical properties of radish pickle containing different natural preservatives (grapefruit seed extract, green tea extract, rosemary, or olive) stored for 0, 1, 2, 3, and 4 weeks. The hardness and color of the radish pickles with the grapefruit seed extract was higher than the other radish pickles during storage from week 0 to week 4. A 14.52% and 13.80% decrease in hardness and color were observed in the radish pickles with grapefruit seed extract (GFE), respectively. In addition, the total phenolic content was highest in the GFE in natural preservatives. Based on the results, GFE was selected as the optimal natural preservatives, and the growth of total viable bacteria and yeast were evaluated. The total viable bacteria and yeast showed similar patterns to the control. These results are expected to be useful in producing radish pickles with optimal quality and contribute to the development of various foods in the food industry.

• Korean journal of food and cookery science
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• v.5 no.2
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• pp.19-25
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• 1989

In order to maks use of Adlay widely, it was analyzed and determined the content of amylose, amylopection. And Ju-ak was made from glutinous rice flours with vairous mixing ratio of Adlay flours and then this was tested for suitability to preparation of Ju-ak. Evaluation was conducted through sensory evaluation and objcetive evaluation. The results are as follow: 1. The content of moisture, total ash, crude protein, crude fat, and carbohydrate in Adlay were shown to be about 10.58%, 84.4%, 17.3%, 3.76%, 66.52%. 2. The amylose and amylopectin content were 15.6%, 84.4%. 3. By the sensory evaluation results the taste of Ju-ak prepared with mixing of 25% and 50% Adlay flour was better than glutinous rice Ju-ak but 75% and 100% mixed flour were undersirable. 4. By the Instron measurement results that hardness tend to increass as the additon level of Adlay increased. Gumminess, Chewiness and Elasticity was not significantly different as the addition level of Adlay increased. Conhesiveness tend to decrease as the addition level of Adlay. 5. Consistency of Ju-ak had significant relationship with hardness and cohesiveness. Moistness had significant relationship with hardness, elasticity, cohesiveness and chewiness. Texture of Ju-ak had significant relationship with hardness, elasticity, cohesiveness and gumminess.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.19 no.2
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• pp.216-223
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• 2010

The general way to process the surface by means of the laser was heat treatment for strengthening the surface hardness. They have used the laser for changing the property of the surface, especially for metal. Generally, it is recent increasing tendency to use the thin plate panel for making things smaller and lightweight. However, thin plate should be strengthened or let the thin plate panel have moment of inertia by means of engraving the groove or wave on them for lightweight and strengthening. Therefore it is expected that the thin plate panel can be harder and more stable through processing the metal surface by laser beam irradiation and the hardness of thin plate possibly can be also changed how many parts of them are harden. Through this research, it can be grasped how the hardness and mechanical characteristic changes according to width and depth of groove by laser affect the max stress by the ratio of $A_H/A_T$ (hardening area/total area) and characteristic of displacement and structural characteristic for making the thin plate harder by the strengthening metal surface of thin plate by laser through the experiment and analysis of FEA can be presented.

• Journal of Powder Materials
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• v.27 no.5
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• pp.365-372
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• 2020

Predicting the quality of materials after they are subjected to plasma sintering is a challenging task because of the non-linear relationships between the process variables and mechanical properties. Furthermore, the variables governing the sintering process affect the microstructure and the mechanical properties of the final product. Therefore, an artificial neural network modeling was carried out to correlate the parameters of the spark plasma sintering process with the densification and hardness values of Ti-6Al-4V alloys dispersed with nano-sized TiN particles. The relative density (%), effective density (g/㎤), and hardness (HV) were estimated as functions of sintering temperature (℃), time (min), and composition (change in % TiN). A total of 20 datasets were collected from the open literature to develop the model. The high-level accuracy in model predictions (>80%) discloses the complex relationships among the sintering process variables, product quality, and mechanical performance. Further, the effect of sintering temperature, time, and TiN percentage on the density and hardness values were quantitatively estimated with the help of the developed model.

• KSBB Journal
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• v.19 no.2
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• pp.98-103
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• 2004

The aim of the present study was to investigate how the hardness of groundwater affects in the alcohol fermentation. Ozone plays an important role to enhance the water quality, resulting in 85% reduction of hardness, and 30% increase in total glucose produced due to increased conductivity and biodegradability of water. After all, experiments using ozone are presented for the improvement of alcohol productivity. Although initially increased slightly alcohol production, higher than expected ethanol production was observed, with ozone treatment resulting in 20% higher production.

• Journal of Powder Materials
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• v.30 no.3
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• pp.210-216
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• 2023

In this study, machine learning models are proposed to predict the Vickers hardness of AlSi10Mg alloys fabricated by laser powder bed fusion (LPBF). A total of 113 utilizable datasets were collected from the literature. The hyperparameters of the machine-learning models were adjusted to select an accurate predictive model. The random forest regression (RFR) model showed the best performance compared to support vector regression, artificial neural networks, and k-nearest neighbors. The variable importance and prediction mechanisms of the RFR were discussed by Shapley additive explanation (SHAP). Aging time had the greatest influence on the Vickers hardness, followed by solution time, solution temperature, layer thickness, scan speed, power, aging temperature, average particle size, and hatching distance. Detailed prediction mechanisms for RFR are analyzed using SHAP dependence plots.