• The Korean Journal of Food And Nutrition
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• v.14 no.6
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• pp.585-590
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• 2001

The purpose of this study was to examine physical properties of the addition of Plantago powder on bread flour and dough fheology of white pan bread. Four levels(0.3, 0.6, 0.9 and 1.2%) of each Plantago powder with bread flour were tested for their effects in dough mixing using rapid visco analyzer, alveogram, farinogram and sensory test. Addition of Plantago powder(0.3, 0.6 and 0.9% ) showed almost same tendency on the initial pasting temperature but 1.2% increased it. Increment of Plantago powder showed increment of peak viscosity and final viscosity, L(extensibility) and G(swelling index) value in alveogram showed decrement with increasing Plantago powder. In farinogram the use of Plantago powder increased consistency and water absorption but decreased development time and stability. White pan bread using Plantago powder had higher value of Max. G and gardeness in rheometer than without using it. Sensory evaluation of white pan bread with 0.6% Plantago powder had the highest score.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.21 no.7
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• pp.585-593
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• 2008

In this work, we report several experimental data capable of evaluating the phase transformation characteristics of GeSbTe pseudobinary thin films comprehensively utilized as phase change materials. The phase transformation of the GeSbTe thin films was confirmed by XRD measurement from amorphous to hexagonal structure via fee structure except for $Ge_8Sb_2Te_{11}$. In addition, X-ray photoelectron spectra analysis revealed to weaken Ge-Te bond for $Ge_2Sb_2Te_5$ and to strengthen the bonds of all elements for $Ge_8Sb_2Te_{11}$ during the amorphous to crystalline transition. The values of optical energy gap $(E_{OP})$ were around 0.71 and 0.50 eV and the slopes of absorption in extended region (B) were ${\sim}5.1{\times}10^5$ and ${\sim}10{\times}10^5cm^{-1}{\cdot}V^{-1}$ for the amorphous and fcc-crystalline structures, respectively. Finally, the kinetics of amorphous-to-crystalline phase change on the GeSbTe films was characterized using a nano-pulse scanner with 658-nm laser diode (power; $1{\sim}17$ mW, pulse duration; $10{\sim}460$ ns).

• Transactions of the Korean Society of Mechanical Engineers A
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• v.38 no.9
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• pp.967-972
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• 2014

The good light permeability and hardness of glass allow it to be used in various fields. Non-conventional machining methods have been used for glass machining because of its brittle properties. As one non-contact machining method, a laser has advantages that include a high machining speed and the fact that no tool making is required. However, glass has light permeability. Thus, the use of a laser to machine glass has limitations. A nanosecond pulse laser can be used at low power for laser-induced backside wet etching, which is an indirect method. In previous studies, a short-wave laser that had good light absorption but a high price was used. In this study, a near-infrared laser was used to test the possibility of glass micro-machining. In particular, when deeper machining was conducted on a glass structure, more problems could result. To solve these problems, microstructure manufacturing was conducted using ultrasonic vibration.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.41 no.7
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• pp.463-468
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• 2017

For transdermal drug delivery, needless injection system is composed of laser and microjet injector. Main mechanism of microjet injector is the laser-induced bubble. Nd:YAG and Er:YAG laser are used as a power source. Laser parameters such as pulse duration and wavelength are considered, which are core parameters to control the bubble motion. The Nd:YAG laser, pulse duration is short than bubble life time making cavitation like bubble while in Er:YAG laser, long pulse duration and high absorption in water drive bubble as a boiling bubble. Detailed motion of bubble and microjet is captured by the high speed camera. So it is observed that microjet characteristics are determined by the bubble behavior. The performance of drug delivery system is evaluated by fluorescent staining of guinea pig skin.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.24 no.4
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• pp.339-347
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• 2014

Floor impact sound in high-rise apartment building became one of social problems. A lot of civil complaints on floor impact sound occur continuously and the number of disputes between neighbors in small and aged apartment buildings is increasing. Interests on heavy-weight impact sound pressure level measurement and evaluation method is increased. Previous study reported that heavy-weight impact sound level was changed by the sound field condition of receiving reverberation chamber. In this study, heavy-weight impact sound pressure level change by the receiving sound field condition was measured in standard test facility and mock-up test room. These two experimental conditions were designed to simulate averaged living room of common apartment units. By the change of sound absorption power in receiving room, heavy-weight impact sound pressure level in most of frequency bands were changed in standard test facility and mock-up room. Normalized maximum sound pressure level regulated in ISO 16032 showed wider range of heavy/soft impact sound pressure level. Heavy/soft impact sound pressure level change was became smaller by the application of standardized maximum sound pressure level and ISO/CD 10140-3 Amd 2 method. In the case of standardized maximum sound pressure level, absolute sound pressure level changed. From these results, receiving sound field correction method regulated in ISO/CD 10140-3 Amd 2 is needed for the precision measurement and evaluation of heavy-weight impact sound.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.688-688
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• 2013

Al-doped ZnO (AZO) thin films have attracted a lot of attention as a cheap transparent conducting oxide (TCO) material that can replace the expensive Sn-doped In2O3. In particular, AZO thin films are widely used as a window layer of chalcogenide-based thin film solar cells such as Cu(In,Ga)Se2 and Cu2ZnSnS4 (CZTS). Mostly important requirements for the window layer material of the thin film solar cells are the high transparency and the low sheet resistance, because they influence the light absorption by the activelayer and the electron collection from the active layer, respectively. In this study, we prepared the AZO thin films by RF magnetron sputtering using a ZnO/Al2O3 (98：2wt%) ceramic target, and the effect of the sputtering condition such as the working pressure, RF power, and the working distance on the optical, electrical, and crystallographic properties of the AZO thin films was investigated. The AZO thin films with optimized properties were used as a window layer of CZTS thin film solar cells. The CZTS active layers were prepared by the electrochemical deposition and the subsequent sulfurization process, which is also one of the cost-effective synthetic approaches. In addition, the solar cell properties of the CZTS thin film solar cells, such as the photocurrent density-voltage (J-V) characteristics and the external quantum efficiency (EQE) were investigated.

• Journal of the Korean Institute of Gas
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• v.15 no.3
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• pp.19-25
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• 2011

Generally, the generation methods of cooling energy are electric air conditioning (EAC) and gas air conditioning (GAC). The EAC system is caused by increasing peak power during summer. Because the electric energy has a characteristic of non-storage, the peak electric load has been issued social problem annually whether the facility to supply is enough or not. Another way to supply cooling energy, GAC system is worked by gas energy. The absorption chiller and gas engine heat pump have been commercialized for cooling. However, the total capacity of GAC is much less than EAC and it almost depends on EAC for small market. This paper described the status of cooling energy consumption in domestic and expected the cooling energy to be consumed by electric and gas energy up to 2024 year. And also the benefit of GAC was analyzed with the case of its expansion and it was aimed to give background to fit the GAC policy.

• Structural Engineering and Mechanics
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• v.40 no.4
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• pp.453-469
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• 2011

A one-story, wooden-frame, intermediate-bay model with Dou-Gon designed according to the Building Standards of the Song Dynasty (A.D.960-1279), was tested on a unidirectional shaking table. The main objectives of this experimental study were to investigate the seismic performance of Chinese historic wooden structure under various base input intensities. El Centro wave (N-S), Taft wave and Lanzhou wave were selected as input excitations. 27 seismic geophones were instrumented to measure the real-time displacement, velocity and acceleration respectively. Dynamic characteristics, failure mode and hysteretic energy dissipation performance of the model are analyzed. Test results indicate that the nature period and damping ratio of the model increase with the increasing magnitude of earthquake excitation. The nature period of the model is within 0.5~0.6 s, the damping ratio is 3~4%. The maximum acceleration dynamic magnification factor is less than 1 and decreases as the input seismic power increases. The frictional slippage of Dou-Gon layers (corbel brackets) between beams and plates dissipates a certain amount of seismic energy, and so does the slippage between posts and plinths. The mortise-tenon joint of the timber frame dissipates most of the seismic energy. Therefore, it plays a significant part in shock absorption and isolation.

• Applied Biological Chemistry
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• v.40 no.4
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• pp.301-306
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• 1997

This study is presented to investigate the physico-chemical properties and qualities for the starch isogenic lines bred in barley(Hordeum vulgare L.).The pearling yield showed higher value in Franubet and Wafranubet than others, but the whiteness of pearled barley varied with the cultivars. The milling rate showed excellence in Franubet, fractured granular lines, whereas that of the waxy and round endosperm isogenic lines is poor. Franubet, the lines having fractures starch granule, was highest in starch content. The highest value in swelling power and water-binding capacity of the barley was proved by the lines having waxy and fractured starch endosperms. The amylogram patterns indicated that the waxy lines such as Wanubet and Wafranubet have lower initial gelatinization temperature and higher maximum viscosity than those of the normal lines. ${\beta}-Glucan\;viscosity$ was generally higher in waxy barley but changed greatly with the cultivars. The water absorption, soluble solid and expansibility in cooking property showed the highest value in waxy and fractured starch granular lines, and the whiteness of cooked barley did not differ with cultivars.

• Journal of Microbiology and Biotechnology
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• v.25 no.6
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• pp.820-827
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• 2015

The present study was performed to investigate the various radical scavenging activities of fermented Undaria pinnatifida by the mycelia fermentation method. U. pinnatifida was fermented with Cordyceps militaris (C. militaris ) mycelia using solid culture and compared with unfermentated U. pinnatifida and C. militaris mycelia for antioxidant activities. The various radical scavenging activities of extracts from U. pinnatifida fermented with C. militaris mycelia (FUCM) were evaluated by electron spin resonance. The antioxidant activities of the FUCM extracts were assayed for ferric reducing antioxidant power, 2,2'-azinobis-(3-ethybenzothiazoline-6-sulfonic acid) radical scavenging activity, and oxygen radical absorption capacity. The free radical scavenging activity of FUCM extracts was higher than that of C. militaris mycelia or U. pinnatifida alone. FUCM extracts were significantly (p < 0.05) increased up to 35 times, 10 times, and 16 times that of U. pinnatifida extracts on DPPH, alkyl, and hydroxyl radical scavenging activities, respectively. These results indicate that FUCM extracts have different chemical ingredients from U. pinnatifida and could provide beneficial antioxidant activity.