• Journal of Korean Tunnelling and Underground Space Association
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• v.15 no.5
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• pp.497-504
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• 2013

This research uses numerical analysis to examine the tunnel portal landscape affecting the brightness level of interior lighting when designing lights for road tunnels through the L20 method. In order to extract the brightness recognition per form of a tunnel entrance and to evaluate the effects of the characteristics of the materials of facilities near a tunnel portal, brightness analysis was conducted by filming brightness on a video photometer called Hi-land Elf System, and a surface brightness photometer called LMK Mobile Advanced. Tunnels in Korea are mostly distributed in mountain areas; thus, the ratio occupied by the sky, which has the highest brightness within the angle of L20, is close to zero, while most of the ratio was occupied by brightness by the area near the tunnel entrance or road surface. However, for a tunnel portal retaing wall, which allows the width of a tunnel entrance to seem wider within the L20 angle, appeared to be have higher brightness compared to nearby areas or the surface, which is an element increasing the tunnel portal brightness within the tunnel, and the road facilities near the tunnel portal appeared to have an effect on the brightness as well. Thus, when designing tunnel lights based on brightness, the form of the tunnel entrance and the area width, material, and color of areas near the tunnel portal appeared to affect outside brightness and become an element affecting the establishment of the brightness level of the interior lights of tunnels. Consequently, reviewing such matters is a prerequisite when designing tunnel portal landscape.

• Korean Journal of Food Science and Technology
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• v.42 no.3
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• pp.257-262
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• 2010

Patulin, a secondary metabolite of mold, is commonly found in rotten apples. Many countries regulate patulin at levels ranging from 30 to $50\;{\mu}g/L$. Most analytical methods for removing patulin from apple juice include liquid-liquid extraction (LLE), which is time and labor intensive. To replace the LLE method, a solid-phase extraction (SPE) method has been developed for apple juice and unfiltered apple juice. A portion of the test sample was applied to a macroporous copolymer cartridge and washed with 5 mL of 1% sodium bicarbonate, followed by 5 mL of 1% acetic acid. Patulin was eluted with 5 mL of 2% acetonitrile in anhydrous ethyl ether. The mobile phase was tetrahydrofuran in water (0.8:99.2) and was detected with a UV detector at 276 nm. Recoveries ranged from 95 to 101% in test samples, and the minimum detectable level was 30 ppb. Because this SPE method is fast, easy, reliable, and inexpensive, it could be applicable for companies or analytical agencies to analyze patulin concentrations in apple juice.

• Food Science and Preservation
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• v.15 no.1
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• pp.88-93
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• 2008

This paper focused on the detection of the genetically modified soybean (Glycine max L. MERRILL) samples to search for the speedy analysis methods. We have identified the PCR (polymerase chain reaction) assay with a newly developed technique called DHPLC (denaturing high performance liquid chromatography) to screen the GMO in soybean. The DHPLC is i1s ability to directly detection specific sequences of DNA by using column. With these characteristics. the DHPLC assay had the advantage of simplicity, rapidty could obtain result within 20 minutes. Whereas $15{\times}10^{-4}ng/{\mu}L$ concentration could be detected with the PCR analysis, $15{\times}10^{-5}ng/{\mu}L$ concentration could be detected with the DHPLC method. Therefore, DHPLC method was considered to be a simple, fast and sensitivity screening method rather than PCR analysis for GMO detection in soybean.

• Analytical Science and Technology
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• v.20 no.4
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• pp.289-295
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• 2007

A simple electric circuit of an infrared photodiode electrode (IPDE) was utilized to monitor iron using square-wave (SW) anodic stripping voltammetry (SV) and cyclic voltammetry (CV). The optimum analytical conditions were determined and were compared with those of common working electrodes. The comparison showed that CV is more sensitive and convenient to use than the common voltammetry methods. At the optimized conditions, the working ranges of 0.1- to 0.8- and 0.85- to 6.0 mg/L iron was obtained. Relative standard deviation of 15 measurements of iron (0.4 mg/L) was 0.09%. The analytical detection limit was found to be $80{\pm}0.6ug/L$, which was applied to iron in waste water.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2009.10a
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• pp.7-10
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• 2009

터널 경계구역 내의 필수 조명기준은 가시기준, 즉 충분한 물체의 대비에 의해 결정된다. 본 연구에서는 터널도로를 대상으로 주간의 터널 입구부의 배경을 디지털 카메라로 측정하고, 그 이미지를 감지대비법의 일종인 광막휘도법(Veiling Luminance Method)과 기존 $20^{\circ}$ 시야의 L20법에 적용하여 터널의 경계부 평균휘도를 산출하였으며, 그 결과를 비교, 분석하였다.

• Clinical and Experimental Pediatrics
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• v.48 no.4
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• pp.387-394
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• 2005

Purpose : We performed this study to compare the TSH and free $T_4$ levels according to gestational age and birth weight, and to reevaluate the cut-off values in the neonatal screening test for congenital hypothyroidism. Methods : Total 2,133 neonates(1,749 healthy newborns and 384 sick neonates) were screened in Dankook University Hospital from May 2000 to January 2003. Neonates with abnormal TSH values (higher than $20{\mu}IU/mL$) or abnormal free $T_4$ levels(lower than 1 ng/dL) were recalled to recheck the thyroid function test. At that time, physical examinations and history-taking regarding perinatal problem, medication history, and mother's illness were undertaken. Results : Serum TSH and free $T_4$ values revealed no significant difference according to sex, delivery type, and Apgar score. The free $T_4$ levels showed statistically significant differences, with gestational age or birth weight(P<0.01). The recall rate of neonates due to abnormal screening test was 7.48 percent. Compared with original cut-off values, the recall rate of the new cut-off values setted to TSH higher than $20{\mu}IU/mL$ or free $T_4$ lower than 0.64 ng/dL decreased from 7.48 percent to 4.8 percent in the healthy group. But, it compromised sensitivity when applied to the sick group. Conclusion : In this study, neonatal free $T_4$ levels were significantly different according to birth weight, gestational age, and the presence of compromised condition. Although the recall rate by TSH > $20{\mu}IU/mL$ or free $T_4$ <1 ng/dL was relatively high, it was impossible to set up new cut-off values without compromising sensitivity. We think studies including a larger study population will be required to change the cut-off values.

• Journal of the Korea Concrete Institute
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• v.20 no.3
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• pp.317-323
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• 2008

In the current study, A model for the flow analysis of fresh and highly flowable concrete has been developed using a particle method, the moving particle semi-implicit (MPS) method. The phenomena on the flow of concrete has been considered as a visco-plastic flow problem, and the basic governing equation of concrete particle dynamics has been based on the Navier-Stokes equation in Lagrangian form and the conservation of mass. In order to formulate a visco-plastic flow constitutive law of fresh concrete, concrete is modeled as a highly viscous material in the state of non-flow and as a visco-plastic material in the state of flow after reaching the yield stress of fresh concrete. A flow test of fresh concrete in the L-box was simulated and the predicted flow was well matched with the experimental result. The developed method was well showed the flow motion of concrete particles because it was formulated to be based on the motion of visco-plastic fluid dynamics.

• Journal of Plant Biotechnology
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• v.30 no.4
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• pp.347-352
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• 2003

This work was undertaken to study the effect of stigmatic and cut-style pollination on self seed set in Lilium longiflorum and L. ${\times}$ formolongi, and their crosses as the female parent with other cultivars/genotypes. Stigmatic pollination of L. longiflorum cv. Gelria and Lorina resulted in cent per cent fruit set with mean number of seeds/fruit of 189 and 70, respectively. However, cut-style pollination resulted in 87％ and 40％ fruit set in Gelria and Lorina, respectively. The corresponding mean number of seeds/fruit was 53 and 20. In L. ${\times}$ formolongi, stigmatic pollination set 80％ fruits with 736 seeds/fruit. On the other hand, cut-style pollination resulted in 47％ fruit set with 81 seeds/fruit. The intraspecific stigmatic pollination of L. longiflorum cv. Gelria and Lorina with other cultivars formed 60％ fruits with a mean number of 18 seeds/fruit. However, only 20％ fruit set with mean number of seeds/fruit of 7 was recorded when cut-style pollination of L. longiflorum cultivar were pollinated with other cultivars/genotypes. In the intraspecific pollination of L. ${\times}$ formolongi cv. Raizan with Novia, fruit set resulting from stigmatic and cut-style pollination was 75％ and 50％, respectively with the corresponding mean number of seeds/fruit of 579 and 98. It was concluded that self as well as intraspecific seed set in the two species of Lilium gets considerably reduced as a result of cut-style pollination.

• KSBB Journal
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• v.21 no.2
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• pp.79-84
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• 2006

In order to minimize the reduction of lysine productivity by accumulation of lysine and byproducts in the end of fed-batch fermentations, a salt-tolerant mutant C14-49-3-15-7-3-20, which could grow at high concentrations of NaCl was isolated through mutagenesis from the Corynebacterium glutamicum mother strain I. In the evaluation of L-lysine productivity by fed-batch fermentations using a 5 L jar fermenter, the salt-tolerant mutant strain C14-49-3-15-7-3-20 produced 130.6 g/L of L-lysine with a 48.6% of yield. The mother strain I produced L-lysine concentration only 104.9 g/L with a yield 41.8%, implying the improvement of L-lysine productivity by introduction of salt-tolerance character.

• Korean Journal of Food Science and Technology
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• v.37 no.4
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• pp.513-518
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• 2005

Capillary electrophoresis (CE) method was developed to determine (+)-catechin and (-)-epicatechin contents in grape seed ethanol extract. CE separation was achieved using 100 mM phosphate and borate buffer at pH 6.0 as background electrolyte and fused silica capillary with 50 microns x 375 microns O.D. (effective length 20.0cm) maintained at $25^{\circ}C$. The applied voltage was 10kV, and detection was performed by DAD at 210 nm, Two catechins were well separated within 6 min with repeatability of <0.8% RSD for migration time and <2.0% RSD for peak area, and correlation coefficients higher than 0.994 were obtained from 58.0 to 174.0 mg/L with detection limit of 0.035 mg/L. Separated compounds were successfully determined. CE method was easy to handle and showed good reproducibility. CE method was compared with conventional coloring and HPLC methods, and main advantages of CE method were low amount of sample required, simple pre-sample treatment, good recovery rate, and short analysis time.