• Progress in Superconductivity
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• v.5 no.1
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• pp.50-54
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• 2003

We have fabricated $∂^2$$B_{z}$ /$∂x^2$ type planar gradiometers and studied their properties in operation under various field conditions. $YBa_2$$Cu_3$$O_{7}$ film was deposited on $SrTiO_3$ (100) substrate by a pulsed laser deposition (PLD) system and patterned into a device by the photolithography with ion milling technique. The device consists of 3 pickup loops designed symmetrically Inner dimension and the width of the square side loops are 3.6 mm and 1.2 mm, respectively, and the corresponding dimensions of the center loop are 2.0 mm and 1.13 mm. The length of baseline gradiometer is 5.8 mm. Step-edge junction width is 3.0 $\mu\textrm{m}$ and the hole size of the SQUID loop is 3 $\mu\textrm{m}$ ${\times}$ 52 $\mu\textrm{m}$. The SQUID inductance is estimated to be 35 pH. The device was formed on a 20 mm ${\times}$ 10 mm substrate. We have tested the behavior of the device in various field conditions. The unshielded gradiometer was stable under extremely hostile conditions on a laboratory bench. Noise level 0.45 pT/$\textrm{cm}^2$/(equation omitted)Hz and 0.84 pT/$\textrm{cm}^2$/(equation omitted)Hz at 1 Hz for the shielded and the unshielded cases, which correspond to equivalent field noises of 150 fT/(equation omitted)Hz and 280 fT/(equation omitted)Hz, respectively. In spite of the short baseline of 5.8 mm, the high common-mode-rejection-ratio of the gradiometer, $10^3$, allowed us to successfully record magnetocardiogram of a human subject, which demonstrates the feasibility of the design in biomagnetic studies.

• Research in Plant Disease
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• v.20 no.4
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• pp.289-294
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• 2014

Rice samples including paddy, husk, brown rice, blue-tinged rice, broken rice, discolored rice and polished rice were collected from rice processing complexes(RPC) nationwide to determine the contamination of fungi and mycotoxins on rice during 2010-2013. Among the samples, paddy rice had the highest frequencies of fungal and Fusarium occurrence, and the frequencies decreased along with milling as husk was the next. Blue-tinged rice or discolored rice was similar with brown rice for fungal occurrence, and polished rice showed the lowest frequency. Among Fusarium species, F. graminearum species complex occupied 87% in 2012 but did 35-39% in 2011 and 2013. Aspergillus and Penicillium species appeared at low frequency in most samples but occurred at higher frequency in certain RPC samples. Alternaria, Nigrospora, and Epicoccum species occurred similarly to the pattern of total fungi. The rice samples from 2010-2012 were analyzed for the occurrence of Fusarium mycotoxins including deoxynivalenol, nivalenol, zearalenone, and other trichothecenes. The most highly contaminated sample was discolored rice in terms of frequency, level, ratio of simultaneous contamination with multiple toxins, followed by blue-tinged rice.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.254-254
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• 2017

This study evaluated the grain quality of local brand rice from 6 major rice exporting countries which are anticipated to export their rice to Korea. Recently, with the end of the postponement of rice import tariffs in 2014, Korea is in a very easy environment to import foreign rice. Therefore, the quality evaluation of local brand rice in those countries is needed to secure the quality competitiveness of Korean rice, also to protect the rice industry in Korea. We provided total 38 local brand rice from USA(7), China(16), Australia(4), Thailand(3), Vietnam(5) and India(3), and 2 imported brand rice through MMA from USA and China to find out the status of the grain quality for each country. For the quality evaluation, we analyzed the physicochemical properties, milling and palatability-related characteristics. The amylose content on country average ranged from 24.4(India)~16.2%(Thailand). The protein content was 6.66% by overall average, and was higher in order of India(7.86), Australia(6.80), Vietnam(6.61), Thailand(6.59), China(6.28), USA(5.82). In Toyo glossiness value, it ranged from 75.7~45.2, and the figures in USA and China were the highest level. The head rice ratio ranged from 95.2~72.4%, and the figures in Thailand, USA and China were distinctly high. When we analyze the palatability of boiled brand rice with Chucheongbyeo as check variety by expert panelists, several rice brands from USA and China showed equal or better scores in shape, smell, taste, stickiness, texture and overall score, although most rice brands showed a tendency to decrease significantly in the taste characteristics compared with Chucheongbyeo. From the above results, it can be seen that the grain quality of USA and China rice is very competitive when imported into Korea. The results will provide basic information for the quality control of foreign rice which will be imported into Korea in the near future, also for the quality information which could be applied on the development of high-quality Korean rice varieties. Continuous monitoring about the foreign brand rice is advisable to improve the quality competitiveness of Korean rice.

• Journal of Technologic Dentistry
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• v.30 no.2
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• pp.39-45
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• 2008

Titanium and its alloys are widely used as dental implants materials because of their excellent mechanical properties. However, the alumina and zirconia ceramics are preferred to use as the substitute of Ti implants because there is a problems in esthetics and biocompatibility in Ti implant. The the glass infiltrated alumina ceramics are studied to increase the toughness and biocompatibility. The 45S5 and soda-lime glass powder was mixed with ethanol at ratio of 1:1 and brushed on the surface of alumina. Then it was heat treated in the electric furnace at $1400^{\circ}C$ from 30 min. to 5 hours. The glass powder was controlled from 200 to $350{\mu}m$ using ball milling. After heat treatment, the glass infiltrated specimen was tested in universal testing machine to measure the bending strength. The surface microstructure of each specimen was observed with SEM. The biocompatibility of 45S5 and soda-lime glass coated alumina was investigated using PBS at $36.5^{\circ}C$ incubator. The specimen was immersed in PBS for 3, 5, 7, 10 days. After that, the surface morphology was investigated with SEM. As the results of experiment, the 45S5 bioglass infiltrated alumina show the increase of bending strength according to the increasing of heat treatment time from 30 min. to 5 hours at $1400^{\circ}C$ Finally the 1370N bending strength of alumina increased to 1958N at 5 hours heat treatment, which shows 1.4 times higher. In contrast to this, the soda lime glass infiltrated alumina ceramics shows the convex curve according to heat treatment time. Thus it shows maximum bending strength of 1820N at 1 hour heat treatment of $1400^{\circ}C$ It gives 1.3 times higher. However, the bending strength of soda lime glass infiltrated alumina is decreasing with increasing heat treatment time after 1 hour. The precipitation on the surface of 45S5 glass infiltrated alumina was revealed as a sodium phosphate ($Na_{6}P_{6}O_{24}6H_{2}O$) and the amount of precipitation is increasing with increasing of immersion time in PBS. In contrast to this, there is no precipitation are observed on the surface of soda lime glass infiltrated alumina. This implies that 45S5 glass infiltrated alumina brings more biocompatible when it is implanted in human body.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.3
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• pp.370-374
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• 2003

Cell cracking method using a non-collision was evaluated for the possibility of new red ginseng grinding technique. Based on particle size distribution analysis by 1size shaker, the ratios of 100 mesh penetrated particles were 94.9% for hammer mill (group A) and 95.6% for cell crack (group B). The ratio of 120 mesh penetrated particle of group A was higher than that in group B. The particle size distributions for 100 mesh non-penetrated Powder between 2 groups were not significantly different, and particle size distribution analysis by laser scattering analyzer showed that the particle size ranges were 0.77~128.07 ${\mu}{\textrm}{m}$ for group A and 4.24~180.07 ${\mu}{\textrm}{m}$ for group B. The Particle size distribution in group A was more broad than that in group B. The mean particle size in group B was larger than that in group A, while the standard deviation of particle size distribution in group B was less than that in group A. Structural surface characteristics, in group A, particle size distribution was broad and the distribution curve was amorphous. The structure of individual particles was similar to unequal stone which was roughly grinded and had soft cotton-like surface. In the contrary, in group B, particle size distribution was relatively narrow and also individual size particles were ubiquitously distributed. The structure of individual particles was unequal cut stone shape.

• The Journal of Korean Academy of Prosthodontics
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• v.42 no.6
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• pp.664-670
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• 2004

Statement of problem. One of the common problems of dental implant prosthesis is the loosening of the screw that connects each component, and this problem is more common in single implant-supported prostheses with external connection. Purpose. The purpose of this study was to examine the changes of detorque values of abutment screws with external connection in different abutment heights. Materials and methods. After cyclic loading on three different abutment heights, detorque values were measured. Abutments were retained with titanium abutment screws tightened to 30 Ncm (30.5 kgmm) with digital torque gauge as recommended by the manufacturer. Replacing abutments, implants and titanium abutment screws with new ones at every measurement, initial detorque values were measured six times. In measuring de torque values after cyclic loading, Avana Cemented Abutments of 4.0 mm collar, 7.0 mm height (Osstem Co., Ltd., Seoul, Korea) were used with three different lengths of 5.0, 8.0, 11.0 mm. Shorter abutments were made by milling of 11.0 mm abutment to have the same force-exercised area of 4.5 mm diameter. Sine curve force (20N-320N, 14Hz) was applied, and detorque values were measured after cyclic loading of 2 million times by loading machine. Detorque values of initial and after-loading were measured by digital torque gauge. One-way ANOVA was employed to see if there was any influence from different abutment heights. Results. The results were as follows: 1. The initial detorque value was 27.8$\pm$0.93 kgmm, and the ratio of the initial detorque value to the tightening torque was 0.91(27.8/30.5). 2. Measured detorque values after cyclic loading were declined as the height of the abutment increased, that was, 5.0 mm; 22.3$\pm$0.82 kgmm, 8.0 mm; 21.8$\pm$0.93 kgmm, and 11.0 mm; 21.3$\pm$0.94 kgmm. 3. One-way ANOVA showed no statistically significant differences among these (p>0.05). 4. Noticeable mobility at the implant-abutment interface was not observed in any case after cyclic loading at all.

• Journal of Biosystems Engineering
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• v.39 no.3
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• pp.227-234
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• 2014

Purpose: The aim of this research was to develop and evaluate natural hydroxyapatite (HA) ceramics produced from the heat treatment of pig bones. Methods: The properties of natural HA ceramics produced from pig bones were assessed in two parts. Firstly, the raw materials were characterized. A temperature of $1,200^{\circ}C$ was chosen as the calcination temperature. Fine bone powders (BPs) were produced via calcinations and a milling process. Sintered BPs were then characterized using field emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD), X-ray fluorescence spectroscopy (XRF), energy dispersive X-ray spectroscopy (EDX), Fourier transform infrared (FTIR) spectroscopy, and a 2-year in vitro degradability test. Secondly, an indirect cytotoxicity test was conducted on human osteoblast-like cells, MG63, treated with the BPs. Results: The average particle size of the BPs was $20{\pm}5{\mu}m$. FE-SEM showed a non-uniform distribution of the particle size. The phase obtained from XRD analysis confirmed the structure of HA. Elemental analysis using XRF detected phosphorus (P) and calcium (Ca) with the Ca/P ratio of 1.6. Functional groups examined by FTIR detected phosphate ($PO{_4}^{3-}$), hydroxyl ($OH^-$), and carbonate ($CO{_3}^{2-}$). The EDX, XRF, and FTIR analysis of BPs indicated the absence of organic compounds, which were completely removed after annealing at $1,200^{\circ}C$. The BPs were mostly stable in a simulated body fluid (SBF) solution for 2 years. An indirect cytotoxicity test on natural HA ceramics showed no threat to the cells. Conclusions: In conclusion, the sintering temperature of $1,200^{\circ}C$ affected the microstructure, phase, and biological characteristics of natural HA ceramics consisting of calcium phosphate. The Ca-P-based natural ceramics are bioactive materials with good biocompatibility; our results indicate that the prepared HA ceramics have great potential for agricultural and biological applications.

• Korean Journal of Food Science and Technology
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• v.26 no.3
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• pp.305-309
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• 1994

Precooked powder of redbean porridge (RP) was prepared by the series of process extrusion, drying, milling and blending with a mixture of whole redbean flour and corn starch and others. The optimum process and quality of products for RP were investigated. After extrusion under the moisture content 24 to 26%, twin screw speed 350 rpm, extrusion temperature 150 to $155^{\circ}C$ and feed rate 60 kg/hr, the product had a higher quality with its natural redbean flavor/color. During the extrusion process, extrusion temperature and specific mechanical energy increased from 150 to $198^{\circ}C$ and from 134 to 144 kwh/ton respectively, as the amount of addition water decreased from 6 to 2 kg/hr. By the hot air drying of redbean extrudate (RE). it could be dried below to 4% moisture content, of which level considered as an optimal moisture content for anti-caking of the powdered product, at $80^{\circ}C$ for 4hrs and at $100^{\circ}C$ for 1.5 hrs respectively. In the sieve analysis of extrudate powder, when the product milled through a mesh size of 0.5 mm or 1.0 mm, about 80% or 65% of the feed was passed a 65 mesh screen respectively. Moisture absorption of final blended products was formed a cake under 100% of relative humidity after 13 hrs of storage. As the amount of RE powder reduced, the flavor score of products decreased by sensory evaluation of products prepared by the different ratio of RE powder, corn starch and sugar.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.56 no.3
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• pp.219-225
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• 2011

The physicochemical properties of rice endosperm from five rice varieties and effects of milling on baking bread properties of rice flour were investigated. Five rice varieties exhibited different level of amylose content. The ratio of longer amylopectin chain length to the distribution of endosperm starches was the highest in Goami3. According to the RVA measurement of rice flours, the pasting temperatures of Seolgaengbyeo and Goamibyeo were lower than those of the other rice varieties. There were differences in the changes of swelling power of rice flour under increasing temperature. Each rice flour sample for bread-making was processed into two different particle size by using an air-classification mill, and significant differences were observed among cultivars in the average particle size and damaged starch content of rice flours. Rice flour of Seolgaengbyeo with fine particle size showed the highest value in specific volume after baking.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.53 no.3
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• pp.244-250
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• 2008

The purpose of this study was to measure fundamental data required for the prediction of milling ratios, and to develop regression models to predict the head rice ratio of milled rice using NIR spectra of hulled rice. A total of 81 rice samples used in this study were collected from Jeongeup, Jeonbuk province in 2006. NIR spectra were measured using one mode of measurement, reflection. The reflectance spectra were measured in the wavelength region of 400-2500 nm with an NIR spectrophotometer "NIRSystems 6500" (Foss, Silverspring, USA). Calibration equations were developed by the modified partial least squares (MPLS), partial least squares (PLS), and principal components regression (PCR). Math treatments were 1-4-4-1, 1-10-10-1, 2-4-4-1, and 2-10-10-1. The software used was WinISI (Infrasoft International, State College, USA). Automatic head rice production and quality checking system used was "SY2000-AHRPQCS" (Ssangyong, Korea). The calibration was made with the first derivative and the spectrum designated was in 8 nm interval. The determination coefficients of head rice ratios were 0.8353, 0.8416 and 0.5277 for the MPLS, PLS and PCR, respectively. Those obtained with 20 nm interval were 0.8144, 0.8354 and 0.6908 for the MPLS, PLS and PCR, respectively. The calibration was made with second derivative that spectrum designated was 8 nm in interval. The determination coefficients of head rice ratios were 0.7994, 0.8017 and 0.4473 for the MPLS, PLS and PCR, respectively. Those with 20 nm interval were 0.8004, 0.8493 and 0.6609 for the MPLS, PLS and PCR, respectively. These results indicate that the accuracy of determination coefficient for MPLS and PLS is higher than that of PCR.