• Asian-Australasian Journal of Animal Sciences
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• v.25 no.9
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• pp.1269-1275
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• 2012

An experiment was conducted to study the effect of soluble protein supplements on concentration of soluble non-ammonia nitrogen (SNAN) in the liquid phase of ruminal (RD) and omasal digesta (OD) of Korean native steers, and to investigate diurnal pattern in SNAN concentration in RD and OD. Three ruminally cannulated Korean native steers in a $3{\times}3$ Latin square design consumed a basal diet of rice straw and corn-based concentrate (control), and that supplemented (kg/d DM basis) with intact casein (0.24; IC) or acid hydrolyzed casein (0.46; AHC). Ruminal digesta was sampled using a vacuum pump, whereas OD was collected using an omasal sampling system at 2.0 h intervals after a morning feeding. The SNAN fractions (free amino acid (AA), peptide and soluble protein) in RD and OD were assessed using the ninhydrin assay. Concentrations of free AA and total SNAN in RD were significantly (p<0.05) lower than those in OD. Although free AA concentration was relatively high, mean peptide was quantitatively the most important fraction of total SNAN in both RD and OD, indicating that degradation of peptide to AA rather than hydrolysis of soluble protein to peptide or deamination may be the most limiting step in rumen proteolysis of Korean native steers. Diurnal variation in peptide concentration in OD for the soluble protein supplemented diets during the feeding cycle peaked 2 h post-feeding and decreased thereafter whereas that for the control was relatively constant during the entire feeding cycle. Diurnal variation in peptide concentration was rather similar between RD and OD.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.622-622
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• 2013

Piezoelectric energy harvesting (PEH) device refers to a power device for acquiring mechanical energy from the environment surrounding us which would otherwise be wasted and for converting it into usable electrical energy. While much work has been done on developing ZnO nanogenerator (NG) with nanowire arrays, there are some issues of not only scaling up its output power but also optimizing structure for operating feasibly in various conditions. Efficiency of NG is highly dependent on fixed orientation. But in many cases, it is not easy to predict where the pressure and vibration may come from. Furthermore, the direction of the applied mechanical stress is usually non-stationary and can be random in various practical applications. Therefore an omnidirectional PEH is needed.In this work, we investigate an omnidirectional PEH device consisting ZnO nanowires. We deposited spiral patterned ZnO seed layer on Kapton film. We deposited thin Cr layer on the ZnO seed layer using DC-sputter to form a passivation layer to retard un-expected growth of ZnO nanowires. We grew ZnO nanowires along the spiral arms using hydrothermal method. ZnO nanowires have been selectively grown from the ZnO sidewall without Cr layer and have the average length of$5{\mu}m$ and the average diameter of 40nm. We reduced the defect in the as-grown ZnO nanowires by O2 plasma using asher and by thermal treatment using RTA. Consequently, each nanowire has different directions to each other. This isotropic design can lead to the omnidirectional power generation. The morphology of NG is characterized with FESEM. Maximum output power of the device is measured by using a picoammeter and a nanovoltmeter.

• Journal of Astronomy and Space Sciences
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• v.30 no.4
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• pp.307-314
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• 2013

Infrared optical systems are operated at low temperature and vacuum (LT-V) condition, whereas the assembly and alignment are performed at room temperature and non-vacuum (RT-NV) condition. The differences in temperature and pressure between assembly/alignment environments and operation environment change the physical characteristics of optical and opto-mechanical parts (e.g., thickness, height, length, curvature, and refractive index), and the resultant optical performance changes accordingly. In this study, using input relay optics (IO), among the components of the Immersion GRating INfrared Spectrograph (IGRINS) which is an infrared spectrograph, a simulation based on the physical information of this optical system and an actual experiment were performed; and optical performances in the RT-NV, RT-V, and LT-V environments were predicted with an accuracy of $0.014{\pm}0.007{\lambda}$ rms WFE, by developing an adaptive fitting line. The developed adaptive fitting line can quantitatively control assembly and alignment processes below ${\lambda}/70$ rms WFE. Therefore, it is expected that the subsequent processes of assembly, alignment, and performance analysis could not be repeated.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.08a
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• pp.155.2-155.2
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• 2013

Strain-relaxed SiGe layer on Si substrate has numerous potential applications for electronic and opto- electronic devices. SiGe layer must have a high degree of strain relaxation and a low dislocation density. Conventionally, strain-relaxed SiGe on Si has been manufactured using compositionally graded buffers, in which very thick SiGe buffers of several micrometers are grown on a Si substrate with Ge composition increasing from the Si substrate to the surface. In this study, a new plasma process, i.e., the combination of PIII&D and HiPIMS, was adopted to implant Ge ions into Si wafer for direct formation of SiGe layer on Si substrate. Due to the high peak power density applied the Ge sputtering target during HiPIMS operation, a large fraction of sputtered Ge atoms is ionized. If the negative high voltage pulse applied to the sample stage in PIII&D system is synchronized with the pulsed Ge plasma, the ion implantation of Ge ions can be successfully accomplished. The PIII&D system for Ge ion implantation on Si (100) substrate was equipped with 3'-magnetron sputtering guns with Ge and Si target, which were operated with a HiPIMS pulsed-DC power supply. The sample stage with Si substrate was pulse-biased using a separate hard-tube pulser. During the implantation operation, HiPIMS pulse and substrate's negative bias pulse were synchronized at the same frequency of 50 Hz. The pulse voltage applied to the Ge sputtering target was -1200 V and the pulse width was 80 usec. While operating the Ge sputtering gun in HiPIMS mode, a pulse bias of -50 kV was applied to the Si substrate. The pulse width was 50 usec with a 30 usec delay time with respect to the HiPIMS pulse. Ge ion implantation process was performed for 30 min. to achieve approximately 20 % of Ge concentration in Si substrate. Right after Ge ion implantation, ~50 nm thick Si capping layer was deposited to prevent oxidation during subsequent RTA process at $1000^{\circ}C$ in N2 environment. The Ge-implanted Si samples were analyzed using Auger electron spectroscopy, High-resolution X-ray diffractometer, Raman spectroscopy, and Transmission electron microscopy to investigate the depth distribution, the degree of strain relaxation, and the crystalline structure, respectively. The analysis results showed that a strain-relaxed SiGe layer of ~100 nm thickness could be effectively formed on Si substrate by direct Ge ion implantation using the newly-developed PIII&D process for non-gaseous elements.

• Nuclear Engineering and Technology
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• v.55 no.6
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• pp.2139-2146
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• 2023

During reactor operation, the divertor must withstand unprecedented simultaneous high heat fluxes and high-energy neutron irradiation. The extremely severe service environment of the divertor imposes a huge challenge to the bonding quality of divertor joints, i.e., the joints must withstand thermal, mechanical and neutron loads, as well as cyclic mode of operation. In this paper, potassium-doped tungsten (KW) is selected as the plasma facing material (PFM), oxygen-free copper (OFC) as the interlayer, oxide dispersion strengthened copper (ODS-Cu) alloy as the heat sink material, and reduced activation ferritic/martensitic (RAFM) steel as the structural material. In this study, a vacuum brazing technology is proposed and optimized to bond Cu and ODS-Cu alloy with the silver-free brazing material CuSnTi. The most appropriate brazing parameters are a brazing temperature of 940 ℃ and a holding time of 15 min. High-quality bonding interfaces have been successfully obtained by vacuum brazing technology, and the average shear strength of the as-obtained KW/Cu and ODS-Cu alloy joints is ~268 MPa. And a fabrication route for manufacturing the flat-type divertor target based on brazing technology is set. For evaluating the reliability of the fabrication technologies under the reactor relevant condition, the high heat flux test at 20 MW/m² for the as-manufactured flat-type KW/Cu/ODS-Cu/RAFM mockup is carried out by using the Electron-beam Material testing Scenario (EMS-60) with water cooling. This paper reports the improved vacuum brazing technology to connect Cu to ODS-Cu alloy and summarizes the production route, high heat flux (HHF) test, the pre and post non-destructive examination, and the surface results of the flat-type KW/Cu/ODS-Cu/RAFM mockup after the HHF test. The test results demonstrate that the mockup manufactured according to the fabrication route still have structural and interfacial integrity under cyclic high heat loads.

• Journal of Bio-Environment Control
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• v.20 no.3
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• pp.227-232
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• 2011

The processing techniques are need to use the non-marketable paprika fruit because paprika that is difficult crop for cultivation and produced easily non-marketable fruits, such as physiological disorder fruit, malformed fruit, and small size fruit. This study was carried out to investigate the proper active modified atmosphere packaging (MAP) condition for enhancing the storability of fresh-cut paprika fruit. The fresh-cut paprika (cv 'Score', seminis) put into $7cm{\times}0.7cm$ size and packed them in 20 g bags. The active MAP and vacuum treated paprika fruits were packaged with LLDPE/Nylon, EVOH, Tie film, and injected partial pressures of $CO_2$ and $O_2$, and $N_2$ in the packages immediately after sealing to treat active MAP. The ratio of $CO_2$, $O_2$, and $N_2$ of active MAP conditions were 0 : 20 : 80 (air), 5 : 5 : 90, 30 : 10 : 60, 10 : 70 : 20 and vacuum treatment did not contain any gas. The passive packaging treated paprika packaged with $40{\mu}m$ ceramic film. After 7 days of storage at $9^{\circ}C$, the fresh weight decreased less than 2% in all treatments, and showed lower in 5 : 5 : 90 ($CO_2:O_2:N_2$) active-MAP treatment and higher in vacuum treatment than other treatments. The $CO_2$ and $O_2$ concentration in packages did not change remarkably in active-MA treatments except 30 : 10 : 60 active-MAP treatment that showed sharply decreased $O_2$, concentration and increased $CO_2$ concentration at $1^{st}$ day of storage at $9^{\circ}C$. The ethylene concentration in package was the highest in 30 : 10 : 60 active-MAP treatment and the lowest in the passive MAP treatment that packaged with gas permeable film during $9^{\circ}C$ storage for 7 days. The 30 : 10 : 60 active-MAP treatments were not proper condition to storage fresh-cut paprika. The visual quality was maintained higher in 0 : 20 : 80 (air), 5 : 5 : 90, and 10 : 70 : 20 active MAP treatments and passive MAP treatment than others and the firmness, off-odor, and electrolyte leakage was investigated at 7th day of storage at $9^{\circ}C$. The 5 : 5 : 90 and 10 : 70 : 20 active-MAP treatment showed higher firmness and lower off-odor than other treatments after $7^{th}$ day of storage at $9^{\circ}C$. In addition, the electrolyte leakage was reduced less than 20% at 0 : 20 : 80 (air), 5 : 5 : 90, 10 : 70 : 20, and passive MA treatments. Therefore, 10 : 70 : 20 ($CO_2:O_2:N_2$) and 0 : 20 : 80 (air) might be recommended for proper active MAP conditions.

• The Journal of the Korea Contents Association
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• v.22 no.10
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• pp.733-741
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• 2022

Among the various evidence found in maritime crimes, fingerprints and DNA are very important in that they can identify a suspect. In this study, 5 types of non-porous surfaces (plastic, stainless, glass, ceramic, FRP), which are often found as evidence in the actual marine environment, were selected, and latent and blood fingerprints were passed down and immersed at the Donghae Maritime Police Station's exclusive pier for about 7 days. After that, DNA extraction, quantification, and STR profile were analyzed after fingerprint developing CA fumming method and 4 powder methods (Swedish black powder, Concentrated black powder, Supranano red powder, Dazzle orange powder). Among the fingerprint developing methods, when Supranano red powder was applied, a relatively high amount of DNA was found. As a result of STR profile analysis, an average of 16.8 to 9 loci were secured, and all 20 were confirmed in glass and ceramic materials. As a result of the study, it was possible to secure the STR profile by extracting and quantifying DNA after applying the fingerprint developing method to virtual evidence immersed for about 7 days, and further research is needed to secure the STR profile by analyzing DNA after applying various fingerprint developing methods such as VMD and SPR.

• Tribology and Lubricants
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• v.38 no.6
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• pp.255-260
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• 2022

This research presents tetrahedral amorphous (ta-C) coating on the artificial tooth for improving the durability and functionality (esthtics, foreign body of tooth) by filtered cathodic vacuum arc (FCVA). A differentiated coating method is required for a ta-C coating on polymer owing to the low melting point of the polymer, inter-facial adhesion, low friction, and non-conductivity. Herein, ta-C coating is applied below 50℃, and the potential difference of the carbon plasma drawn to the substrate was controlled by applying a positive duct bias voltage without using a substrate bias voltage. Consequently, the ta-C coating with a thickness of 70nm using the duct bias condition of 20V with the highest plasma intensity satisfies the esthetics of the artificial tooth and had a 5B level of inter-facial adhesion. In addition, the composite hardness of ta-C/polymer is 380 MPa, and correlations with esthetics, sp³ bonding, and mechanical properties. The friction coefficient (CoF) of the ta-C coating in a water-lubricated environment is 0.07, showing a six-fold reduction in CoF compared with that of a polymer.

• Journal of Bio-Environment Control
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• v.22 no.2
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• pp.175-181
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• 2013

These studies were identified the effect of four types of non-perforated breathable (NPB) packing film and three sizes on storage ability of fresh-cut for ready to eat packaging at $5^{\circ}C$ for 25 days and $10^{\circ}C$ for 15 days storage in Salicornia herbacea. The fresh weight loss was less than 2% in every films at $5^{\circ}C$ condition after 25 days storage, and the $10^{\circ}C$ also had same result on 15 days storage except 100,000 cc NPB film. Compare with storage after 15 days, storage condition at $5^{\circ}C$ had shown better result under the 1% fresh weight loss rate. The 5,000 cc and $5^{\circ}C$ condition had been shown the characteristics of MA packaging in carbon dioxide and oxygen concentrations. The ethylene concentration in vacuum film was higher 10 to 100 times than in NPB film treatments during storage. But ethylene concentration was not statistically significant differences among size treatments. Every conditions had been measured the anti-oxidant activity by DPPH method after storage at $5^{\circ}C$ for 25 days and $10^{\circ}C$ for 15 days. S. herbacea at $5^{\circ}C$ had been more than twice of activity compare with that at $10^{\circ}C$. 100,000 cc NPB film had been higher contents of anti-oxidant activity at $5^{\circ}C$ and $10^{\circ}C$. As the fresh-cut sizes, 3 cm and 5 cm sizes had changed depending on film types but 10 cm were not effected by the film types in the DPPH activity. When panel test had been tried to measure the visual quality and off-flavor after storage, $5^{\circ}C$ with a filme of 5,000 cc treatment had established higher value than other treated conditions. As these results, it's may be suggested that the $5^{\circ}C$ with 5,000 cc non-perforated breathable film for MA storage in Salicornia herbacea at fresh cut distribution system. Fresh cut size 10 cm with 100,000 cc NPB film also had the good quality for 15 dyas storage at $10^{\circ}C$, and this result can be applied for short term distribution system in Korea.

• Journal of Soil and Groundwater Environment
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• v.10 no.2
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• pp.35-43
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• 2005

Bioslurping combines the three remedial approaches of bioventing, vacuum-enhanced free-product recovery, and soil vapor extraction. Bioslurping is less effective in tight (low-permeability) soils. The greatest limitation to air permeability is excessive soil moisture. Optimum soil moisture is very soil-specific. Too much moisture can reduce air permeability of the soil and decrease its oxygen transfer capability. Too little moisture will inhibit microbial activity. So Modified Fenton reaction as chemical treatment which can overcome the weakness of Bioslurping was experimented for simultaneous treatment. Although the diesel removal efficiency of SVE process increased in proportion to applied vacuum pressure, SVE process was difficulty to remediation quickly semi- or non-volatile compounds absorbed soil strongly. And SVE process had variation of efficiency with distance from the extraction well and depth a air flow form of hemisphere centering around the well. Below 0.1 % hydrogen peroxide shows the potential of using hydrogen peroxide as oxygen source but the co-oxidation of chemical and biological treatment was impossible because of the low efficiency of Modified Fenton reaction at 0.1 % (wt) hydrogen peroxide. NTA was more efficiency than EDTA as chelating agent and diesel removal efficiency of Modified Fenton reaction increased in proportion to hydrogen peroxide concentration. Hexadecane as typical aliphatic compound was removed less than Toluene as aromatic compound because of its structural stability in Modified Fenton reaction. What minimum 10% hydrogen peroxide concentration has good remediation efficiency of diesel contaminated groundwater may show the potential use of Modified Fenton reaction after bioslurping treatment.