• Bulletin of the Korean Chemical Society
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• v.30 no.1
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• pp.102-106
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• 2009

A rapid and sensitive chemiluminescence (CL) method using flow-injection (FI) has been developed for the determination of mandelic acid which is based on the enhancement of mandelic acid to the CL intensity of ${Ru(bipy)_{3}}^{2+}$-Ce(IV) system. The enhancement effect was dependent on the concentration of mandelic acid, based on which, CL system was established for the determination of mandelic acid. The concentrations of ${Ru(bipy)_{3}}^{2+}$+, Ce(IV), and $H_2SO_4$ were optimized. Under the optimum experimental conditions, the linear range and detection limit are 1.46-342.0 ${\mu}g/ml$ and 0.072 ${\mu}g/ml$, respectively. The correlation coefficient (R) was 0.99732. The utility of this method was demonstrated by determining mandelic acid in capsules and human urine sample.

• Journal of the Korean Society of Safety
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• v.22 no.1 s.79
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• pp.13-18
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• 2007

Structural integrity assessment of thin-walled pipes and pipe items has become one of the major issues in the nuclear power plant. ASME Section XI Code Case N-597-2 provides a criterion for acceptance of the pipes. But the code case has several limitations for application and sometimes gives too conservative or non-conservative results. So it is necessary to understand fully the technical bases of the code case. In the code case N-597, the allowable local thicknesses of thinned straight pipes are given for three different cases. Because of the different technical base, each case gives different thickness values and sometimes gives contradictory values. In this paper attempts were made in order to propose a unified rule for the allowable local thickness and in order to remove or relax the restrictions on the application of the code case. For this purpose elastic stress analyses were made using the finite element method and the stress results were examined. Based on the obtained bending stress results, a very simple procedure was proposed to obtain the consistent allowable local thickness for the thinned straight pipes.

• The KIPS Transactions:PartD
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• v.9D no.3
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• pp.487-494
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• 2002

In this paper, we present an equation edition system, which is designed and implemented according to the W3C MathML standard. The system can be used to edit equations for the various web-oriented applications. Various user-friendly interfaces are provided for the easy and efficient edition of equations. The edited equations can be viewed immediately with the representation modules. To improve the processing speed of equations, we upgraded functions of the conventional XML parser. The presented system will contribute to the extensive usage of equations on the web and efficient processing of XML documents with equations.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.07a
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• pp.197-198
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• 2005

본 논문에서는 p-type (100)Si. (100)MgO 그리고 MgO/Si 기판 위에 RF Magnetron sputtering 법으로 $Ba_{0.5}Sr_{0.5}TiO_3$(BST) 박막을 증착 후 $600^{\circ}C$ 의 질소분위에서 RTA(Rapid Thermal Annealing)를 이용한 1 분간의 고온 급속열처리를 하였다. XRD 측정결과 모든 기판에서 (110) $Ba_{0.5}Sr_{0.5}TiO_3$의 주피크가 관찰되어졌고, 열처리 후 피크 세기가 증가함을 확인할 수 있었다. C-V 특성에서 각각의 기판에서 측정된 커패시턴스 값으로 계산된 유전율은 120(bare Si), 305(MgO/Si) 그리고 310(MgO)이었다. 누설 전류 특성에서는 150KV/cm이내의 인가전계에서 0.1$uA/cm^2$이하의 안정된 누설전류값을 보여주었다. 결론적으로 MgO 버퍼층을 이용한 기판이 BST 박막의 증착을 위한 기판으로써 효과적임을 알 수 있었다.

• Wind and Structures
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• v.17 no.3
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• pp.275-298
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• 2013

This paper presents a number of approximated analytical formulations for the flutter analysis of long-span bridges using the so-called uncoupled flutter derivatives. The formulae have been developed from the simplified framework of a bimodal coupled flutter problem. As a result, the proposed method represents an extension of Selberg's empirical formula to generic bridge sections, which may be prone to one of the aeroelastic instability such as coupled-mode or single-mode (either dominated by torsion or heaving mode) flutter. Two approximated expressions for the flutter derivatives are required so that only the experimental flutter derivatives of ($H_1^*$, $A_2^*$) are measured to calculate the onset flutter. Based on asymptotic expansions of the flutter derivatives, a further simplified formula was derived to predict the critical wind speed of the cross section, which is prone to the coupled-mode flutter at large reduced wind speeds. The numerical results produced by the proposed formulas have been compared with results obtained by complex eigenvalue analysis and available approximated methods show that they seem to give satisfactory results for a wide range of study cases. Thus, these formulas can be used in the assessment of bridge flutter performance at the preliminary design stage.

• Journal of the Korean Society of Physical Medicine
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• v.16 no.1
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• pp.9-16
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• 2021

PURPOSE: This study was to investigate the effect of applying neck flexion during elbow flexion exercise on muscle activity of the biceps brachii, the anterior deltoid and the sternocleidomastoid (SCM). METHODS: Twenty healthy adults participated in this study. The subjects measured %MVIC (Maximal volumetric control) and collected the maximum electromyography (EMG) values in the biceps brachii, anterior deltoid, SCM. The first action was to sit in a sitting position with the eyes facing front and maintained the weight of each section by performing elbow flexion using a tension gauge. The second action was to sit in a sitting position with the head down and maintained the weight of each section by performing elbow flexion using a tension gauge. Paired T-test was used for comparison of the before-and-after neck flexion to analyze the muscle activity of the Biceps brachii of next flexion and extension, the SCM, and the Anterior deltoid during elbow flexion exercise. The Repeated measured ANOVA was used for comparing %MVIC in each muscle. The significance level (?) was set at .05. RESULTS: Neck flexion during elbow flexion increased the muscle activity of the Biceps brachii and Anterior Deltoid muscle in the maximal muscle strength 50 ~ 60%, 70 ~ 80% and decreased the muscle activity of the SCM (p < .05). CONCLUSION: The applic has been confirmed to reduce the mobilization of the SCM and increase the mobilization of the Biceps brachii and Anterior Deltoid to increase the mobilization. Therefore, it seems effective to apply neck flexion when elbow flexion exercise.

• Applied Chemistry
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• v.15 no.1
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• pp.33-36
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• 2011

A chemiluminescent method with gold nanoparticles for determination of vitamin C has been presented. Gold nanoparticles highly increased chemiluminescence intensity of lumimol-H₂O₂ system by its catalytic effect. The gold nanoparticles enhanced chemiluminescent method is applicable for the determination of an antioxidant such as vitamin C. When vitamin C was introduced to the lumimol system with gold nanoparticles, chemiluminescence intensity was reduced with the concentration of the added vitamin C. Low concentrated vitamin C solutions in the range of 1×10^-3-1×10^-9 M were produced reduced chemiluminescence intensity of lumimol-H₂O₂ with gold nanoparticles system.

• Proceedings of the Korea Information Processing Society Conference
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• 2023.11a
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• pp.1234-1236
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• 2023

광대역(Wideband) 통신은 신호 대역폭이 채널의 상관 대역폭(Coherence Bandwidth)를 크게 초과하는 시스템을 나타낸다. 이때, 큰 대역폭을 갖을수록 반송 주파수대역과 사용대역의 최대 및 최소 주파수 간 차이가 커지며, 통신 시스템이 겪는 채널의 주파수 선택적 페이딩 또한 커지게 된다. 수중에서 광대역 통신을 성능을 확인하기 위한 실험을 수행하였다. 실험환경으로는 송·수신기 간 수평 이격거리는 약 10m, 수직 이격거리는 약 190m로 설정하였다. 광대역 신호의 성능을 확인하기 위하여 14kHz와 30kHz의 주파수 대역과 협대역신호와의 비교를 위해 16kHz와 4kHz 대역폭 등 파라메타를 달리하여 설정하였다. x축을 Repetition Freq.와 Repetition Time의 조합으로 설정하였으며, y축을 BER(Bit Error Rate)로 성능결과를 나타내었다.

• The Korean Journal of Physiology and Pharmacology
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• v.12 no.4
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• pp.205-209
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• 2008

Recently, Sun et al (2008) reported that the IL6R polymorphism is associated with schizophrenia. Therefore, to detect the association between polymorphisms of interleukin 31 receptor A (IL31RA) and schizophrenia, we genotyped 9 SNPs [rs9292101 (intron 1), rs1009639 (exon 2, Pr043Pro), rs2161582 (intron 2), rs68761890 (intron 5), rs16884629 (intron 6), rs11956465 (intron 12), rs12153724 (intron 12), and rs16884641 (intron 14)] using the Golden Gate assay on Illumina BeadStation 500 GX. Two hundred eighteen patients with schizophrenia and 379 normal subjects were recruited. Patients with schizophrenia were diagnosed according to DSM-IV, and control subjects without history of psychiatric disorders were selected. We used SNPStats, Haploview, HapAnalyzer, SNPAnalyzer, and Helixtree programs for the evaluation of genetic data. Of nine polymorphisms, three SNPs (rs9292101, rs1009639, and rs11956465) were associated with schizophrenia. The rs9292101 and rs11956465 showed significant associations with the risk of schizophrenia in the codominant [rs9292101, odds ratio (OR)=0.74, 95% confidence interval (CI)=0.58${\sim}$0.95, p=0.017] and recessive (rs11956465, OR=0.64, 95% CI=0.42${\sim}$0.96, p=0.034) models, respectively. The rs1009639 also was statistically related to schizophrenia in both codominant (OR=0.76, 95% CI=0.60${\sim}$0.97, p=0.025) and dominant (OR=0.66, 95% CI=0.44${\sim}$0.98, p=0.035) models. Two linkage disequilibrium (LD) blocks were made. In the analysis of haplotypes, a haplotype (GCT) in block 1 and a haplotype (CCACAG) in block 2 showed significant associations between schizophrenia and control groups (haplotype GCT, frequency=0.509, chi square=4.199, p=0.040; haplotype CCACAG, frequency=0.289, chi square=5.691, p=0.017). The results suggest that IL31RA may be associated with risk of schizophrenia in Korean population.

• Journal of Life Science
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• v.18 no.9
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• pp.1225-1229
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• 2008

A total of 10 polymorphic microsatellite markers on bovine chromosome 5 were used for allelic association tests with phenotypic characteristics in Hanwoo. The data analyzed in this study were collected from 326 steers. Chi-square tests were performed to compare the frequencies of individual alleles between the high and the low breeding value groups. The following breeding values were analyzed for QTL effects. The frequency of allele 239 of DIK2828 showed a significant difference between the high and the low breeding value groups in the breeding value of marbling score (MSBV). The allele 279 of BMC1009 was found to show significant differences in allelic distribution for the breeding value of cold carcass weight (CWBV) and the breeding value of backfat thickness (BFBV) and allele 285 showed significant differences in allelic distribution for CWBV, BFBV, and MSBV. The allele 200 of DIK4329 showed significant differences in allelic distributions for the breeding values of longissimus muscle area (LMABV) and BFBV. In this study, we identified the QTL for carcass traits at around 20 (DIK2828), 41 (BMC1009) and 95 (DIK4329) cM in chromosome 5. The results provided a useful reference for further positional candidate gene research and marker-assisted selection for fat metabolism and carcass traits.