• Korean Journal of Food Science and Technology
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• v.41 no.1
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• pp.64-68
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• 2009

The effects of drying methods (hot air, cold air, vacuum, and infrared drying) on physicochemical and organoleptic qualities of sliced-dried persimmons (Diospyros kaki Thumb. cv. Cheungdobansi) were investigated. The weight of the sliceddried persimmons ranged from 9.30 to 12.01 g, the length from 3.55 to 4.06 cm, the width and thickness were from 3.17 to 3.73 cm and 1.82 to 2.04 cm, respectively. Hot air drying resulted in the highest hardness value as well as Hunter's L, a, and b values. Infrared drying showed the lowest L value and vacuum drying revealed the lowest a and b values. Moisture contents of the sliced-dried persimmons ranged from 38.04 to 46.41%, and soluble solid contents were 42.96-$48.44^{\circ}Bx$. The phenolic compounds and DPPH radical scavenging activity were high for infrared and vacuum drying methods, and all the sliced-dried persimmons showed relatively high antioxidant activities. The sensory evaluation results indicated that the organoleptic scores for the overall preference were high in the order of vacuum > infrared > hot air > cold air drying. These results suggest that the drying methods affected the qualities of the sliced-dried persimmons, showing that vacuum drying is the mast effective among the methods tested for manufacturing the high-quality sliced-dried persimmons.

• Korean Journal of Food Science and Technology
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• v.42 no.6
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• pp.714-720
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• 2010

This study was carried out to investigate the effects of Hericium erinaceum (HE) powder and extract on the quality characteristics of noodles. The water binding capacity of the HE powder was higher than that of pure wheat flour. Gelatinization temperature of HE powder-wheat flours gradually were increased and initial viscosity at $95^{\circ}C$, viscosity at $95^{\circ}C$ after 15 min and maximum viscosity of those composites were decreased, as measured by a amylograph. The noodles showed decreased L values and increased a and b values with increasing HE powder in the wheat flour composite. The mechanical properties of the control cooked noodles showed the highest hardness, which decreased with the addition of HE powder. Springiness, cohesiveness, and gumminess decreased with increasing amounts of added HE powder. While the higher adhesiveness of noodles increased with more preferred than the control, and considerably the greatest overall acceptability of noodles was for those containing 2% HE powder.

• Korean Journal of Food Science and Technology
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• v.29 no.6
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• pp.1213-1221
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• 1997

Effects of the addition of three commercial oligosaccharide syrups into a Korean rice cake (Karedduk) on the textural characteristics and retrogradation of the rice cake were examined during the storage for 5 days at $25^{\circ}C$ and $4^{\circ}C$. Each syrups contained maltose (M75), isomaltose and panose (HL), or maltotetraose (G4) as major sugars. The increment (rates) in gumminess, hardness and chewiness during the storage were significantly reduced by replacing rice flour (up to 10%) with the oligosaccharides. The retardation in the textural changes by the oilgosaccharides was more significant when the rice cake was stored at $25^{\circ}C$ than at $4^{\circ}C$. Among the three types, HL exhibited most effective in retarding the textural changes. Thermograms by a differential scanning calorimeter (DSC) showed that the oligosaccharide increased the onset temperatures and enthalpy for the starch melting, but the recrystallinity measured from the enthalpy ratio before and after the storage was significantly reduced by the presence of the oligosaccharide. Especially with 5% HL, the recrystallinity was significantly low (72.7%) compared to rice cake without HL (88.1%). Therefore, HL had great efficiency in retarding starch retrogradation as well as textural changes of the rice cake during the storage.

• The Journal of Korean Academy of Prosthodontics
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• v.44 no.2
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• pp.229-242
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• 2006

Statement of problem: In order to increase preload with reducing the friction coefficient, abutment screws coated with pure gold and Teflon as dry lubricant coatings have been introduced. But the reported data indicate that if screw repeated tightening and loosening cycle, an efficiency of increasing preload was decreased by screw surface wearing off. Purpose: This study was to evaluate the influence of tungsten carbide/carbon coating, which has superior hardness and frictional wear resistance, on the preload of abutment screws and the stability of coating surface after repeated closures. Material and method: The rotational values of abutment screws and the compressive forces between abutment and fixture were measured in implant systems with three different joint connections, one external butt joint and two internal cones. Moreover the stability and the alteration of coating surface were examined by comparison of the compressive force and the removable torque values during 10 consecutive trials, observation with scanning electron microscope and analyzed the elemental composition with energy dispersive x-ray spectroscopy Results and conclusion: 1. Application of coating resulted in significant increase of compressive force in all implant systems(P<.05). The increasing rate of compressive force by coating in external butt joint was gloater than those in internal cones (P<.05). 2. Coated screw showed the significant additional rotation compared to non-coated screw in all implant systems (P<.05). There were no significant differences in the increasing rate of rotation among implant systems (P>.05). 3. Removable torque values were greater with non-coated screw than that with coated screw (P<.05). 4. Coated screw showed insignificant variations in the compressive forces during 10 consecutive trials(P>.05) 5. After repeated trials, the surface layer of coated screw was maintained relatively well. However surface wearing and irregular titanium fragments were found in non-coated screw.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.3
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• pp.417-422
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• 2002

Salting conditions on organoleptic properties and rheology of Chinese cabbage were optimized and monitored by four-dimensional response surface methodology. Experimental conditions were decided in the ranges of salt concentration 8∼12%, salting time 5∼25 hr and salting temperature 5∼15$^{\circ}C$. The salted Chinese cabbage with experiment design was measured on organoleptic and physical properties. The organoleptic form of the salted Chinese cabbage showed maximum score in 11.28% of salt concentration, 9.75 hr of salting time and 12.81$^{\circ}C$ of salting temperature. The organoleptic taste was maximized in 11.19% of salt concentration, 11.38 hr of salting time and 13.58$^{\circ}C$ of salting temperature. The organoleptic mouth-feel was maximized in 11.24% of salt concentration, 11.71 hr of salting time and 13.57$^{\circ}C$ of salting temperature. The organoleptic palatability was maximized in 11.52% of salt concentration, 12.86 hr of salting time and 13.07$^{\circ}C$ of salting temperature. In rheological properties of salted Chinese cabbage, hardness and chewiness decreased with the increase of salt concentration.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.3
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• pp.460-464
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• 2002

Quality of noodle processed by addition of hot water extract powder from roasted safflower seed (RSHE) was investigated. Proximate compositions of RSHE was 4.70% of moisture, 32.63% of crude Protein, 6.52% of crude fat, 15.62% of crude ash and 40.53% of carbohydrate. There was no significant difference (p<0.05) in hunter's color value between noodles with and without RSHE. The ‘L’vague of noodle processed by addition of powder from roasted safflower seed (RSP) was very low and significantly different (p<0.05) from other products. With the increase of RSHE addition, the volume and weight of cooked noodles increased (R$^2$=0.9688). The breaking force of dry noodle decreased with the increase of RSHE addition. In the mastication test of cooked noodles, max. weight, strength and hardness increased with the increase of RSHE addition. Dry noodle with 0.3% and 0.5% RSHE recorded high rank, but that with RSP recorded the lowest rank in score of appearance and color by sensory evaluation. The noodle processed with 0.3∼0.5% RSHE showed high sensory quality.

• Journal of the Korea Institute of Military Science and Technology
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• v.20 no.6
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• pp.752-757
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• 2017

Analysis has been performed for the penetration of a long-rod into MMC/Ceramic layered armour system with several shot test and a series of simulations. Two types of MMC plate have been fabricated by a liquid pressing method; A356/45%vol.%SiCp with a uniform distribution of SiC particle and Al7075/45%vol.B4Cp with B4C particle. The mechanical properties were measured with the high-speed split Hopkins bar test, hardness test and compression test. The popular Simplified Johnson-Cook model was adopted to represent the material characteristics for FEM simulations. The performance of the MMC applied armour system has been made by comparing with the semi-infinite mild steel target using the depth of penetration(DOP). The results show that placing ceramic front layer provides a certain gain in protection, and that placing another ductile front layer provides a further gain. The application of MMC is found to be attractive.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.11
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• pp.7549-7554
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• 2015

The aim of this study was to develop gastric retentive bi-layered tablet using floating drug delivery technique. Metformin was selected as a model drug due to its narrow absorption window as well as very highly water solubility. These properties of metformin led to be difficult controlling the drug release. The bi-layered tablet was prepared with bi-layered compression machine to minimize interference between floating part and controlling part. The tablet weight, appearance and hardness were evaluated after compression process. The times of 'time to floating' and 'Floating duration' were tested for floating ability and drug release study was also carried out to understand drug release behavior. Furthermore, the drug release of bi-layered tablet was compared with marketed metformin tablet with sustained release pattern (Glucopharge XR$^{(R)}$).The floating ability and drug release behaviors were well controlled by changing amounts of $NaHCO_3$ (floating substance) and hydroxypropyl methylcellulose (HPMC; release control material). Bi-layered tablet had 13s of time to float, over 10h of floating duration and very similar drug release behavior compared with Glucopharge XR$^{(R)}$($f_2$: 89.6). Consequently, the bi-layered tablet with floating ability was successfully prepared and these properties can maximize the efficacy of metformin.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.12
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• pp.5438-5442
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• 2011

In order to use as weight-reduced sintered parts for automobiles, mechanical properties of sintered compacts of 2712 Al-alloys containing 0, 10, 20, and 33% ceramics, respectively, were investigated in this study. (1)Regardless of ceramic contents, all sintered compacts possessed 4~7% pores. (2)After aging the compacts sintered for 12 minutes, tensile strength of the 2712 Al-alloys containing 0, 10, 20, and 33% ceramics was 165, 260, 256, and 166 N/$mm^2$, respectively, whereas those aged after sintering for 30 minutes exhibited the tensile strength of 186, 229, 219, and 202 N/$mm^2$, respectively. In addition, the 2712 sintered compact containing 10% ceramics showed the maximum elongation of about 3.6%, (3)After aging the 10% ceramic-containing sintered compacts reached a maximum apparent hardness ($H_RF$) of 97. (4)The minimum wear volume ($174{\times}10^{-3}mm^3$) was shown in the 10% ceramic-containing 2712 sintered compact after aging. From these results, the 2712 sintered compact containing 10% ceramics thought to be the most suitable one for the fabrication of aluminum engine part.

• Journal of the Korean institute of surface engineering
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• v.50 no.6
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• pp.465-472
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• 2017

The ingot fabrication conditions related with the thermal shock bearing phase and microstructure have investigated for the rare earth zirconate ceramic material, lanthanum gadolinium zirconate, as a thermal barrier coating using electron beam evaporation method. The thermal shock resistance of the prepared ingot was evaluated by high energy electron beam irradiation. The rare earth zirconate ceramic powder was prepared by controlling the raw material powder composition of $La_2O_3$, $Gd_2O_3$ and $ZrO_2$ so as to have a composition of $(La_{0.3}Gd_{0.7})_2Zr_2O_7$ which was selected from the former study. Ingot samples were prepared under two conditions. The first condition is prepared by sintering the prepared powder mixture to form an ingot. The second condition is prepared by calcining the prepared powder mixture to form a composite phase and then sintering to form an ingot. X-ray diffraction(XRD) and Scanning Electron Microscope(SEM) were used to analyze phase forming behavior and microstructure of ingot samples. Nanoindentation method used to obtain elastic modulus and hardness of each ingot specimen. Also the stress distribution of ingot was simulated by using FEM method assuming the ingot surface was exposed to electron beam. As a results, in the case of an ingot having a network-shaped microstructure in which relatively coarse pores are included, it seems that the thermal shock resistance was higher than in the case of an ingot having a microstructure composed of relatively fine grains only or particles with the similar level size when the high energy electron beam irradiation.