• Proceedings of the Korea Concrete Institute Conference
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• 2004.11a
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• pp.133-136
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• 2004

This study concerns the. new equation of concrete strength by schmidt hammer test. There are not only few estimate strength equations of concrete by schmidt hammer test, but also many problems to apply them because of time, cost, easiness, structural damage, reliability and so on. For this study, there performed a series of schmidt hammer test with in existing 730days' concrete structures and proposed equations as follows; $$Linear\;:\;f_{ck}=2.18R-40.54\;(r^2=77.7\%)$$ $$Quadratic\;:\;f_{ck}=0.076R^2-2.92R+40.04\;(R^2= 85.5\%)$$ here, fck : Estimated compressive strength of concrete by MPa, R : Rebound index of concrete.

• Nuclear Engineering and Technology
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• v.54 no.9
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• pp.3181-3204
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• 2022

The variational nodal method for solving the neutron transport equation has evolved over 40 years. Based on a functional form of the Boltzmann neutron transport equation, the method now comprises a complete set of variants that can be employed for different problems. This paper presents an extensive review of the development of the variational nodal method. The emphasis is on summarizing the whole theoretical system rather than validating the methodologies. The paper covers the variational nodal formulation of the Boltzmann neutron transport equation, the Ritz procedure for various application purposes, the derivation of boundary conditions, the extension for adjoint and perturbation calculations, and treatments for anisotropic scattering sources. Acceleration approaches for constructing response matrices and solving the resulting system of algebraic equations are also presented.

• Journal of the Korean Society of Food Culture
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• v.23 no.6
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• pp.761-770
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• 2008

The purpose of this study was to determine the optimum amount of four ingredients (spirulina, sugar, lemon and orange) for the preparation of spirulina madeleine using response surface methodology. Spirulina was added at a level of 3.5-6.0 g, sugar powder, at 40-60 g, while lemon and orange peel were included at a level of 0-8 g. The optimum mixing rates of spirulina powder, sugar powder, lemon and orange were 3.5, 40, 0, and 8 g for overall quality and 3.52, 54.42, 0, and 8 g for maximum score of overall organoleptic quality, respectively.

• Journal of The Korean Society of Grassland and Forage Science
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• v.19 no.3
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• pp.189-196
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• 1999

This study was conducted to evaluate the dry matter yield, quality and utilization of nutrients of wild Korean lespedeza as a forage legume sources. Dry matter(DM) yield of stages, chemical composition and DM digestibility were observed, also DM intake, digestibility and utilization of nitrogen and energy by Korean native goats were determined. Experimental diets include three treatrnents ; mixture grass hay(GS), GS 80% + lespedeza(LA) 20% and GS 60% + LA 40%, respectively. The DM yield of Korean lespedeza(LA) with advancing the growing stage tended to significantly increase(P<0.05). The average DM yield was observed 7,336kg/ha. CP content of LA tended to decrease, but fiber content tended to increase at growing stage advanced(P<0.05). The tannin content of LA was highest in bud stage (54.5mg/g), but tended to decrease at growing stage advanced, lowest in seed ripe stage(26.8mg/g) (P<0.05). With increasing the level of LA supplementation, DM intake by Korean native goats slightly increased, but no differences were observed in all diets. The digestibility of DM, cellular constituents and NDF were slightly lower for GS 100% diets than LA 20% and 40% supplemented diets(P<0.05). Apparently digested N% was not detected significant differences in all diets, but retained N and biological value were higher for LA supplemented diets than for GS 100% diets (P<0.05). Utilization of DE and ME was not detected significant differences in all diets. Above the results, it could be suggested that LA have a potential to provide as forage legume sources considering the DM yield, DM digestibility and nitrogen utilization.

• Elastomers and Composites
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• v.54 no.2
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• pp.110-117
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• 2019

The characterization of the ozone oxidation for raw natural rubber (NR) was investigated under controlled conditions through image and fourier transform infrared (FT-IR) analysis. The ozone oxidation was performed on a transparent thin film of raw NR coated on a KBr window in a dark chamber at $40^{\circ}C$ under low humidity conditions to completely exclude thermal, moisture, or light oxidation. The ozone concentration was set at 40 parts per hundred million (pphm). Before or after exposure to ozone, the image of the thin film for raw NR was observed at a right or tilted angle. FT-IR absorption spectra were measured in the transmission mode according to ozone exposure time. The ozone oxidation of NR was determined by the changes in the absorption peaks at 1736, 1715, 1697, and $833cm^{-1}$, which were assigned to an aldehyde group (-CHO), a ketone group (-COR), an inter-hydrogen bond between carbonyl group (-C=O) from an aldehyde or a ketone and an amide group (-CONH-) of protein, and a cis-methine group ($is-CCH_3=CH-$, respectively. During ozone exposure period, the results indicated that the formation of the carbonyl group of aldehyde or ketone was directly related to the decrement of the double bond of cis-1,4-polyisoprene. Only carbonyl compounds such as aldehydes or ketones seemed to be formed through chain scission by ozone. Long thin cracks with one orientation at regular intervals, which resulted in consecutive chain scission, were observed by image analysis. Therefore, one possible two-step mechanism for the formation of aldehyde and ketone was suggested.

• Journal of Medicine and Life Science
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• v.19 no.3
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• pp.103-108
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• 2022

In 2021,the incidence of newly notified tuberculosis in Jeju Province decreased by 23.0% compared to that in the previous year. This was the largest decline among the 18 municipalities studied. This study aimed to examine trends in the incidence of tuberculosis among different age and sex groups in Jeju Province between 2017 and 2021. This study observed the number of new cases in the annual report from 2017 to 2021, published by the Jeju Center for Infectious Diseases Control and Prevention. The average annual percentage change (AAPC; %) was calculated to determine the trend in crude incidence rates over the past 5 years by sex and age. While a P-value of <0.1 was considered marginally significant, aP-value of <0.05 was considered statistically significant. The AAPC of all age groups in Jeju Province had negative values. In men,there was a statistically significant decrease in ages 30-34, 40-44, 45-49, and 50-54 years and a marginally significant decrease in ages 35-59, 55-59, 60-64, 65-69, 75-79, and ≥80 years. In women, a statistically significant decrease was observed among patients aged 30-34, 35-39, and ≥80 years, and a marginally significant decrease was observed among patients aged 45-49, 50-54, 60-64, 65-69, and 75-79 years. A statistically significant decrease in tuberculosis was observed among patients in their 30s and 40s, and elderly patients aged ≥80 years comprised the group vulnerable to tuberculosis. Based on these findings, tuberculosis prevention and screening programs conducted in Jeju Province were effective.

• Journal of Korean Ophthalmic Optics Society
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• v.4 no.2
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• pp.129-133
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• 1999

For the myopia eyes of the people which are ametropia, the classified distribution has showed % for the simple myopic, 50% for the compound myopic astigmatism, 15% for the simple myopic astigmatism and 19% for the mixed astigmatism. The myopic ametropia for the both eyes has the distribution of 35% for -0.50D~-2.00Dptr, 54% for -2.00~6.00Dptr, and 11% for over -6.00Dptr. The classifying distribution for the age for the myopic ametropia was 54% for 15~20, 22% for 21~40, 14% for 41~60 and 10% for 61. The occupational distribution for the myopic ametropia has showed 61.5% for the student(Middle, High, College), 13.5% for the office worker, and 15% for the house wives as well as the small business. The hour affecting the refraction most for a day was after P.M. 7 which recorded 45% as the highest value. The reason is that the myopia degree decreases in the morning as the cornea flats and the situation is reversed in the afternoon so that there is a difference of Sph -0.50D and as getting darker the refraction degree of the light coming through the enlarged pupil refraction around the cornea is high. For the seasons the highest myopic degree has been recorded for 68% in the summer due to the shortage of nutrition and the climination inside the body by the exhaustion of sweat. In the blood types A and B are distributed closely as 34% and more active man with O has recorded higher myopic degree than woman. However woman showed higher accommodation power than man regardless the blood types. In the characteristic factors of myopic eye, the character feels fatigue easily has showed the distribution for 42% which is the highest and it could be classified largely by two the.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.2
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• pp.236-240
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• 2002

Characteristics of ostrich egg shell and optimal ashing conditions for preparation of calcium lactate were investigated. Average weight, girth, and length of ostrich egg shell with membrane (OESM) were 255.17 g, 39.50 cm, and 15.20 cm, respectively. Ostrich egg shell without membrane (OES) contained 0.35% moisture, 40.98% Ca as a maior mineral, 2.43% protein, and 235.0 mg/100 g of amino acids. Optimal ashing times for preparation of white-colored ashing powder from OES were 12 hr at $700^{\circ}C$, 80 min at 80$0^{\circ}C$, and 15 min at 90$0^{\circ}C$, respectively. These ashing conditions resulted in ashing powder with yields of 54.5~54.6% and color values of 97.26 ~97.51 for $L^{*}$, -0.30~-0.34 for $a^{*}$, and 0.63~0.98 for $b^{*}$. Ashing powders, from three different particle size ranges of OES, did not show significant differences in yield.eld.d.

• Korean Journal of Radiology
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• v.22 no.12
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• pp.1996-2005
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• 2021

Objective: To investigate the multidetector computed tomography (MDCT) features of fumarate hydratase-deficient renal cell carcinoma (FH-deficient RCC) with germline or somatic mutations, and compare them with those of papillary type II RCC (pRCC type II). Materials and Methods: A total of 24 patients (mean ± standard deviation, 40.4 ± 14.7 years) with pathologically confirmed FH-deficient RCC (15 with germline and 9 with somatic mutations) and 54 patients (58.6 ± 12.6 years) with pRCC type II were enrolled. The MDCT features were retrospectively reviewed and compared between the two entities and mutation subgroups, and were correlated with the clinicopathological findings. Results: All the lesions were unilateral and single. Compared with pRCC type II, FH-deficient RCC was more prevalent among younger patients (40.4 ± 14.7 vs. 58.6 ± 12.6, p < 0.001) and tended to be larger (8.1 ± 4.1 vs. 5.4 ± 3.2, p = 0.002). Cystic solid patterns were more common in FH-deficient RCC (20/24 vs. 16/54, p < 0.001), with 16 of the 20 (80.0%) cystic solid tumors having showed typical polycystic and thin smooth walls and/or septa, with an eccentric solid component. Lymph node (16/24 vs. 16/54, p = 0.003) and distant (11/24 vs. 3/54, p < 0.001) metastases were more frequent in FH-deficient RCC. FH-deficient RCC and pRCC type II showed similar attenuation in the unenhanced phase. The attenuation in the corticomedullary phase (CMP) (76.3% ± 25.0% vs. 60.2 ± 23.6, p = 0.008) and nephrographic phase (NP) (87.7 ± 20.5, vs. 71.2 ± 23.9, p = 0.004), absolute enhancement in CMP (39.0 ± 24.8 vs. 27.1 ± 22.7, p = 0.001) and NP (50.5 ± 20.5 vs. 38.2 ± 21.9, p = 0.001), and relative enhancement ratio to the renal cortex in CMP (0.35 ± 0.26 vs. 0.24 ± 0.19, p = 0.001) and NP (0.43 ± 0.24 vs. 0.29 ± 0.19, p < 0.001) were significantly higher in FH-deficient RCC. No significant difference was found between the FH germline and somatic mutation subgroups in any of the parameters. Conclusion: The MDCT features of FH-deficient RCC were different from those of pRCC type II, whereas there was no statistical difference between the germline and somatic mutation subgroups. A kidney mass with a cystic solid pattern and metastatic tendency, especially in young patients, should be considered for FH-deficient RCC.

• Microbiology and Biotechnology Letters
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• v.20 no.4
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• pp.477-482
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• 1992

A bacterial strain Acinetobacter calcoaceticus was examined for its ability to degrade fats, oils and hydrocarbons, and tested for the possibility of application in wastewater treatment. All fats and oils tested were degraded by the strain. About 60% of hexadecane, 26% of fish oiL and 40-54% of vegetable oils were consumed respectively in shaking-flask culture. Saturated fatty acid compositions were about 55% in fish oil and 6-12% in vegetable oils. Increases in cell mass were accompanied with decreases in the concentrations of carbon sources. When jar fermentor in place of shaking-flask was used as a culturing vessel. above 80% of all carbon sources was consumed and yield of cell mass was improved to nearly 1.00. Synthetic wastewaters containing 3% of fat, oil, or hydrocarbon as a sale ca,bon source were treated sequentially with A. calcoaceticus first and then exposed to activated sludge. The concentrations of carbon sources were decreased below 0.06% through the process, and the concentrations of suspended solids were lower than 53 mglml. The data imply the potential use of A. calcoaceticus in wastewater treatment.