• Proceedings of the Korean Vacuum Society Conference
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• 2013.08a
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• pp.203.2-203.2
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• 2013

Hydrothermally grown ZnO nanorods were synthesized with various Sn contents on quartz substrates, ranging from 0 to 2.5 at% in increment 0.5 at%. Scanning electron microscopy (SEM) and ultraviolet (UV)- visible spectroscopy were used to determine the effect of Sn doping on the structural and optical properties. In the SEM images, the nanorods have hexagonal wurzite structure and the diameter of the nanorods increase with increase in the Sn contents. The optical parameters of the Sn-doped ZnO nanorods such as the absorption coefficients, optical bandgaps, Urbach energies, refractive indices, dispersion parameters, dielectric constants, and optical conductivities were gained from the transmittance and reflectance results. In the PL spectra, the NBE peaks in the UV region decrease and blue-shift with increase in the Sn contents. In addition, the DLE peaks in the visible region of the nanorods shift toward low-energy region when the ZnO nanorods doped with various Sn contents.

• Journal of the Korean Society for Heat Treatment
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• v.7 no.2
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• pp.139-146
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• 1994

In the molten state, magnesium alloys vigousey react with oxygen in the air, is protected from oxidation and burning by the addition of $SF_6$ to $CO_2$ atmosphere over the melt. The mechanical properties and metallographic examinatin have made of Mg-Al alloys containing 3, 6, 9% in the solution treated state and precipitated state, comparing mechanical properties obtained during unidirectional solidification with me chanical properties obtained during conventional casting. For a given solution treatment, a higher aluminum contents produce more or less fine grains in conventional casting. For a given artifical aging treatment, a higher aluminum contents produces much precitates at the grain boundary as well as within the grain in unidirectional solidification. As a result of this experiment, for a given heat treatment, the higher is aluminum contents the higher is the ultimate tensile strength, yield strength, hardness while the lower the elongation. Also the mechanical properties of unidirectional solidification is larger than that of conventional casting.

• Journal of the Mineralogical Society of Korea
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• v.19 no.2 s.48
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• pp.89-98
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• 2006

The thermal conductivities of bentonite blocks with various dry densities (1.6 and $1.8g/cm^3$), water contents (5, 9.4, 15, 20 wt%) and sand contents (0, 10, 20, 30 wt%) were measured in order to investigate the improvement in physical performance of buffer as an engineered barrier. The raw material was domestic bentonite from Oksan mine located in Gyeongju city. The increase in water content was most effective for improving the thermal conductivity. Especiallly, the bentonite blocks with more than 15 wt% of water content showed more than 1.0 W/mK values of thermal conductivity regardless of their dry densities and sand contents. Therefore, if the domestic Oksan bentonite is used as a buffer material, we can suggest that the manufacture of bentonite block having dry density of $1.6g/cm^3$, sand content of $10{\sim}30$ wt% and water content of 15 wt% will be most effective considering the easiness of a manufacturing of bentonite block and the efficiency of an increase in the thermal conductivity.

• Korean Journal of Poultry Science
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• v.17 no.2
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• pp.101-107
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• 1990

Apparent and true metabolizable energy (AME and TME) contents and true amino acid availability (TAAA) values of full-fat seed, oil meal and oil of canola were assayed employing mature Single Comb white Leghorn roosters. For AME, test diets containing 30% level of canola full-fat seed, oil meal, oil meal plus oil or 10% level of oil were fed for a 3-day adaptation period, followed by a 4-day fecal collection period. For TME and TAAA, 30g test diets were force-fed and total excreta were collected for 48 hours, following a 24 hour fasting period. Metabolizable energy values were corrected to zero nitrogen balance(AMEn and TMEn), Canola contained 4,485, 1,984,8,275 and 5,655kcal/kg of AMEn and 4,577, 2,103, 8,487 and 5,630kcal/kg of TMEn for full-fat seed, oil meal, oil and mixture of meal plus oil, respectirely. The mixtures of oil meal plus oil had significantly higher available energy contents than the full-fat seeds (p＜0.01) . In general, TAAA values of full-fat seed were higher than those of oil meal.

• Journal of Radiation Industry
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• v.5 no.1
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• pp.47-54
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• 2011

In this study, we investigated to evaluate differential expression of genes encoding lipid transfer proteins (LTP) by acute and chronic gamma irradiation in rice. After acute and chronic gamma irradiation by 100 Gy and 400 Gy to rice plant, necrotic lesion was observed in the leaf blade and anthocyanin contents were increased. We isolated a total of 21 rice lipid transfer protein (LTP) genes in the TIGR database, and these genes were divided into four different groups on the basis of nucleotide sequences. The LTP genes also were classified as different four classes according to expression pattern using RT-PCR. Group A, B contained genes with increased expression and decreased expression in acute and chronic, respectively. Group C contained genes with contrasted expression pattern. Group D wasn't a regular pattern. But the specific affinity was not obtained between two grouping.

• Journal of Radiation Industry
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• v.5 no.1
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• pp.7-13
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• 2011

The present study has been performed to compare the physiological analysis of monocot model plant (rice) in response to ionizing irradiations (cosmic-ray, gamma-ray, and Ion beam). Ionizing radiations were implanted into monocot model plant (rice) seed. After irradiation, the seeds were planted in the plastic pots for a growth period of one month. Thereafter, the morphological and physiological characteristics including malondealdehyde (MDA) and chlorophyll content, activities of antioxidant enzymes in irradiation samples were investigated. We are confirmed that the activity level of MDA and chlorophyll content were not changed by ionizing irradiation samples. However, the free radical contents were increased in all irradiated plants. And the activities of SOD, POD, and APX were significantly increased by irradiation compared with non-irradiation plant.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.22 no.3
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• pp.201-206
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• 2022

Energy harvesting is a concept introduced in 1954 by Bell Labs in the US while conducting research on solar cells that convert sunlight into energy. Such energy harvesting technology is a technology that collects wasted or unused energy in daily life and recycles it as electric power. In particular In the case of a photovoltaic power generation system, energy harvesting can be applied by storing electricity generated by using a battery to reduce power consumption generated by the inverter in the form of loss of power generation in cloudy weather compared to sunny days. Therefore, in this paper, energy harvesting technology is applied in the low sunlight section such as sunrise, sunset, and cloudy weather to improve the amount of power generation by recovering the power that is below the minimum operating voltage of the inverter and dissipated. Accordingly, the research contents were verified through the development of systems and algorithms according to the amount of solar power generation and the development of systems and algorithms using low power generated in sunset, sunrise, and other environments.

• Journal of the Korean Society for Library and Information Science
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• v.48 no.2
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• pp.287-306
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• 2014

Many researches have been processing on research records management and way of service for efficient usage of various records from R&D process. Especially, a study on type analysis and structured method of research records is very important for efficient knowledge transfer system. This study, as a basic study for integrated research record management system, is about how to structuralize records efficiently reflecting features of research records. First, analysis and systematization of broad records type made from atomic energy technology R&D process were conducted. Second, efficient methods for contents structuralization in terms of usage to maximize usage of research records were studied. This research tried to structuralize all records based on TOC enable to link, search and use of data for reflecting of integrated and systematic structure which is a feature of research record.

• Journal of the Institute of Electronics and Information Engineers
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• v.53 no.11
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• pp.82-88
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• 2016

In this paper, we propose an intelligibility enhancement algorithm for multimedia contents using spectral shaping. The dialogue signals is essential to understand the plot of audio-visual media contents such as movie and TV. However, the non-dialogue components as like sound effects and background music often degrade the dialogue clarity. To overcome this problem, this paper tries to improves the dialogue clarity of audio soundtracks which contain important cues for the visual scenes. In the proposed method, the dialogue components are first detected by soft masker based on speech presence probability (SPP) which is widely used in speech enhancement field. Then, extracted dialogue signals are applied to the spectral shaping method. It reallocate the spectral-temporal energy of speech to enhanced the intelligibility. The total energy is maintained as unchanged via a loudness normalization process to prevent saturation. The algorithm was evaluated using the modeled and real movie soundtracks and it was shown that the proposed algorithm enhances the dialogue clarity while preserving the total audio power.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.20 no.5
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• pp.1005-1012
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• 2016

LED beacons operated on an isolated marine area are mostly employing the solar power supply system, and this system is well known for increasing the cost of management and maintenance. Recently, a number of researches and demonstrations on self-contained LED beacon is actively conducted to solve this issue. In this work, we propose an self-contained LED beacon with Bluetooth Low Energy function for an effective management of LED beacon. Firstly, control program structure is designed by expanding the status protocol of self-contained LED beacon, and then it is implemented into the form which administrator can easily understand. The control system visualizes the status and control data of self-contained LED beacon, and this enables the rapid decision-making of administrator. Also, minimizing electricity consumption of the beacon, it can transfer and update the status or light information of self-contained LED beacons with smart phone.