• Korean journal of food and cookery science
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• v.29 no.2
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• pp.137-146
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• 2013

Premature-green wheat is typically obtained by early harvest when culms of wheat still appear green in color, and the wheat and its food products have been considered as wellbeing foods. The pasting properties of prematured whole green wheat powder (WGWP), were analyzed with a rapid viscosity analyzer (RVA), and compared with commercial flours. The RVA values of lower peak viscosity and time, holding strength, final viscosity, as well as breakdown and setback viscosity showed that the WGWP could retard a gelatination of starch and also delay retrogradation in bakery products. WGWP with different levels of 10, 20, 30 or 50% was added into flours for preparing bakery product (bread, muffin and cookie), and their quality properties were evaluated. The addition of WGWP lead to a reduction in loaf volume of bread and muffin, and bakery products containing different levels of WGWP showed the changed internal surface structure (e.g. pore size) observed with a scanning electron microscope when compared with the control (0% WGWP). The hardness, gumminess, chewiness of bread and muffins were increased, and cohesiveness was decreased as the WGWP content increased, but the hardness of cookies was decreased. The bakery products added WGWP showed darker and more greenish and yellowish color than control (p<0.05). The sensory evaluation showed that bakeries with WGWP were scored to have more greenish taste and green color (p<0.05), and muffins and cookies with WGWP were evaluated to have more nutty and less oily taste (p<0.05).

• Journal of the Mineralogical Society of Korea
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• v.18 no.3 s.45
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• pp.195-204
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• 2005

Interlayered structures of talc and chlorite in the talc deposits of the Yugu area are studied using transmission electron microscope. Packets of chlorite-like layer in talcs or packets of talc-like layer in chlorites are commonly observed. Randomly interlayered features of talc and chlorite are locally observed in some specimens. Reactions observed in the present study include the addition or removal of a brucite-like layer in the interlayer region of the talc or chlorite resulting in the , transformation between a talc and a chlorite layers and breakdown or formation of a talc-like layer resulting in transformation between two talc layer and one chlorite layer. Both reactions are accompanied by a significant change in volume. In addition to these mechanisms, there are two volume conserving mechanisms; the combination of both mechanisms and mutual transformation in a complex manner. Reactions from 2 chlorite layers to 3 talc layers, from 2 chlorite layers + 1 talc layers to 1 chlorite layers + 3 talc layers, and from 3 chlorite layers to 5 talc layers are observed among the complex type mechanisms.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.51 no.8
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• pp.340-346
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• 2002

Capacitor material utilized in the downsizing passive devices and integration of passive devices requires the physical and electrical properties at given area such as capacitor thickness reduction, relative dielectric constant increase, low leakage current and thermal stability. common capacitor materials, $Al_2O_3$, $SiO_2$, $Si_3N_4$, $SiO_2$/$Si_3N_4$, TaN and et al., used until recently have reached their physical limits in their application to integration of passive devices. $Ta_2O_{5}$ is known to be a good alternative to the existing materials for the capacitor application because of its high dielectric constant (25~35), low leakage current and high breakdown strength. Despite the numerous investigations of $Ta_2O_{5}$ material, there have little been established the clear understanding of the annealing effect on capacitance characteristic and conduction mechanism. This study presents the dielectric properties $Ta_2O_{5}$ MIM capacitor structure Processed by $O_2$ RTA oxidation. X-ray diffraction patterns showed the existence of amorphous phase in $600^{\circ}C$ annealing under the $O_2$ RTA and the formation of preferentially oriented-$Ta_2O_{5}$ in 650, $700^{\circ}C$ annealing and the AES depth profile showed $O_2$ RTA oxidation effect gives rise to the $O_2$ deficientd into the new layer. The leakage current density respectively, at 3~1l$\times$$10_{-2}$(kV/cm) were $10_{-3}$~$10_{-6}$(A/$\textrm{cm}^2$). In addition, behavior is stable irrespective of applied electric field. the frequency vs capacitance characteristic enhanced stability more then $Ta_2O_{5}$ thin films obtained by $O_2$ reactive sputtering. The capacitance vs voltage measurement that, Vfb(flat-band voltage) was increase dependance on the $O_2$ RTA oxidation temperature.

• Journal of the korean academy of Pediatric Dentistry
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• v.25 no.1
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• pp.103-115
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• 1998

Adhesion of composite resin to tooth structure has been of tremendous signgicance in clinical dentistry. Due to the lack of adhesion between composite restorative resins and enamel and dentin, microleakage occurs at the tooth/restoration interface. This may lead to discoloration, secondary caries, marginal breakdown, postoperative sensitivity, and even pulpal pathology. According to extensive use of composite resin, every effort on improving bonding strength and reducing microleakage between a tooth and composite resin has been continued. This study was conducted to determine the difference in microleakage in enamel and dentin treated with air-abrasion, acid etching and combination when restored with composite resin. Class V cavities were prepared on 30 premolars. The specimens were divided into following groups. group 1:air-abrasion+Scotchbond Multi-purpose group 4 :air-abrasion+All-Bond 2 group 2:acid etching+Scotchbond Multi-purpose group 5 :acid etching+All-Bond 2 group 3:combination+Scotchbond Multi-purpose group 6 :combination+All-Bond 2 #combination:air-abrasion + acid etching The specimens were filled with Z-100 after application of Scotchbond Multi-purpose and All-Bond 2. Thermocycling was conducted by alternately dipping the specimens in $5^{\circ}C$ and $55^{\circ}C$ water for 30 seconds 500 times. 1% methylene blue was applied and the specimens were left for 24 hours at $37^{\circ}C$. After washing out the dye, the tooth was sectioned buccolingually along the axis. The sectioned surface was observed with stereoscope for dye penetration. The author has measured the microleakage in teeth prepared with air-abrasion, acid ethching and combination to study the difference in microleakage following different methods of tooth surface treatment and has come to following results. 1. In comparing microleakage between groups, group 1 and 4 showed statistically significant difference from group 2, 3, 5 and 6(p<0.05). There was no significant difference among group 2, 3, 5, 6(p>0.05) nor between group 1 and 4(p>0.05). 2. In comparing microleakage among tooth surface treatment methods, Air-abrasion group showed significantly more microleakage than acid etching group and combination(airabrasion + acid etching) group(p<0.05). Combination(acid etching+air-abrasion)group tended to show lesser microleakage than acid etching group, but this was not statistically significant(p>0.05). 3. In comparing microleakage between bonding agents, there was no statistically significant difference between Scotch bond Multi-purpose and All-Bond 2(p>0.05).

• Polymer(Korea)
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• v.26 no.5
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• pp.644-652
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• 2002

This study aims at developing the conductive pastes consisting of room temperature vulcanizing (RTV) silicone and metal powder as matrix and filler, respectively. Electrical and rheological properties of metal - filled polymer composites are in general strongly affected by particle shape, side and dispersion state of the filler. In highly filled systems, particles tend to form very complex agglomerated structure which is easily changed when subjected to shear deformation. And the breakdown of agglomerated particles due to shear usually leads to the change of electrical conductivity of the composite. In this study, the effect of particle size and dispersion state of filler on the electrical conductivity of the composites are investigated to offer the selection criteria of conductive filler by measuring the rheological properties of uncured composites and the electrical conductivity of the cured composites. It was found that the type of metal filler systematically affected the rheological property, the susceptibility to shear and the degree of change of electrical conductivity of the composite. The effect of shear on the properties is more conspicuous in the composites containing large particle, indicating that both rheological and electrical properties can be improved by controlling the dispersion state at a given filler content.

• Korean Journal of Food Science and Technology
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• v.28 no.1
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• pp.169-178
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• 1996

Target parameters such as water solubility index (WSI), intrinsic viscosity (IV), water holding capacity (WHC), oil holding capacity (OHC), soluble dietary fiber (SDF) and microstructure were investigated on three different screw configurations during twin-screw extrusion of wheat bran. WSI of raw wheat bran (RWB) was 13.7%, while that of extrudates ranged $16.3{\sim}23.2%$ when extruded using screw configurations with 5 reverse screw elements (RSE). It was found that the moisture content of RWB greatly affected WSI of extrudates. IV of wheat bran extrudates increased from 10.6 ml/g of RWB to $37.86{\sim}44.37\;ml/g$ of extrudates extruded using 3, 4 and 5 RSE, whose trend was highly related to the moisture content of RWB and the extrusion pressure. Multiplication of IV and soluble solid (SS) content exhibited good correlation $(R^2=0.85)$ with specific mechanical energy (SME). The results suggested that SS and molecular size are an important factor governed by the SME in solubilization of wheat bran. WHC increased with increasing feed rate and moisture content, while OHC decreased. SDF increased from 2.68% of RWB to $4.32{\sim}6.48%$ of extruded wheat bran, indicating the significant breakdown of cell wall components. Microstructure of the extrudates showed the distinct patterns of degradation and solubilization of cell wall structure, depending on the moisture content of RWB.

• Korean Journal of Food Science and Technology
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• v.28 no.1
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• pp.44-52
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• 1996

Sensory properties of cooked rice were affected by the varieties and growing environments of the rice. Moistness, cohesiveness, and adhesiveness of cooked rice were highly and positively correlated each other, whereas firmness was negatively correlated with these attributes. Sixty rice samples which differed in varieties and/or growing environments were divided into four groups based on their textural properties through principal component analysis and cluster analysis. Quality type I showed the highest values for moistness, cohesiveness, and adhesiveness, and the lowest values for firmness of cooked rice. On the other hand, quality type IV showed just the opposite values. There was no significant difference among rice starches in amylose content (P<0.05). A17 (type III) and A09 (type IV) had higher blue values for starch and amylopectin than the other samples (type I and II). On the amylogram, these samples showed lower values for breakdown and higher values for setback than the other samples. Average degree of polymerization, average chain length, and average number of chains for amylose and amylopectin were 597-878 and 2660-3140, 140-230 and 17-19, and 3.1-4.9 and 140-170, respectively.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.21 no.6
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• pp.25-32
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• 2021

In this study, it proposes a mode converter that is relatively easy to implement and can shorten the transmission line length of the final combining port and it was fabricated and tested by applying it to an 8-way spatial combiner. The proposed mode converter converts the signal converted from the doorknob-shaped circular disk connected to the ground into the TM₀₁ mode by opening it in the circular waveguide. The 8-way waveguide spatial combiner is designed and implemented so that 8 signals input from the H-plane are combined in a circular waveguide at the center, and the final combining mode is TM₀₁. The test results confirmed excellent performance with an insertion loss of less than 0.4dB and a combining efficiency of 95% or more. In addition, it was confirmed that it is suitable for high output by calculating the breakdown voltage and discharge threshold power of the new mode conversion structure through electric field analysis. The results confirmed through this study are expected to be applicable to high-power, high-efficiency SSPA in various fields in the future.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.12
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• pp.211-217
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• 2020

Technology planning in the defense field aims to develop core technologies in order to develop weapon systems to satisfy the force integration period by researching and analyzing necessary technologies for weapon systems. In the past, core technology development projects were conducted by deriving core technology based on the main required operational capability. But in this case, there is the limitation that technologies which are necessary to develop weapon systems but do not directly affect required operational capability, such as system integration technologies, are not considered. In this paper, we propose a work breakdown structure-based technology research and analysis methodology that prevents vacant technologies by identifying core technologies that must be secured for the development of weapon systems at the component level. With the proposed methodology, it is possible to identify technologies that must be acquired to realize the required operational capability of systems or which must be secured even they do not affect the required operational capability.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.1D
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• pp.115-123
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• 2006

Recently, construction claims have been increased for protecting the rights of construction participants and effectively adjusting the changes under the contract. Thus, the importance of claim management has been emphasized in the construction industry. In domestic construction industry, some claim issues involved in construction activities are often being developed into disputes and even litigations because of the absence of methods or systems for the dispute resolution, and the lack of judicial precedents which can be provided as the references for resolving a particular dispute. In general, the judicial precedents related to the disputes and litigations occurred among construction participants would be extremely valuable in evaluating and analyzing current claims issues. However, such useful information has not been effectively accumulated and utilized in resolving the similar or sometimes identical types of disputes, thus requiring a large amount of additional costs, time and efforts. The primary objective of this study is to propose a web-based decision support system for construction claim management, which enables contractual participants to easily access and use the information of the judicial precedents related to the current construction claims. The decision support system is composed of 'prevention' and 'settlement' modules for avoiding and systematically resolving the construction claims.