• Korean Journal of Optics and Photonics
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• v.19 no.1
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• pp.60-67
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• 2008

An all-optical 4-bit Gray code to binary coded decimal (BCD) converter by means of commercially available numerical analysis tool (VPI) was demonstrated, for the first time to our knowledge. Circuit design approach was modified appropriately in order to fit the electrical method on an all-optical logic circuit based on a cross gain modulation (XGM) process so that signal degradation due to the non-ideal optical logic gates can be minimized. Without regenerations, Q-factor of around 4 was obtained for the most severely degraded output bit (least significant bit-LSB) with 2.5 Gbps clean input signals having 20 dB extinction ratio. While modifying the two-level simplification method and Karnaugh map method to design a Gray code to BCD converter, a general design concept was also founded (one-level simplification) in this research, not only for the Gray code to BCD converter but also for any general applications.

• Korean Journal of Optics and Photonics
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• v.16 no.3
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• pp.266-274
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• 2005

We have designed photonic crystal based bandpass filters whose characteristics are suitable for WDM communication system. The filters consist of coupled point defect resonators in two-dimensional photonic crystal. The frequency response of coupled resonators has been analyzed by the coupling of modes in time, from which the design parameters for the coupled resonator filters have been extracted. For the appropriate choice of the design parameters, each resonator is treated as a lumped L-C resonance circuit, and from the analogy between the equivalent circuit and the standard L-C filter circuits, the design parameters are simply determined from the table for general filter circuit design. Based on the determined design parameters, a photonic crystal based filter has been designed and its performance has been calculated using the finite-difference time-domain method. The designed filter shows a pass band of 50GHz and 0.5 dB in-band ripple, which is suitable for typical WDM communication systems with 100GHz channel spacing.

• Journal of Genetic Medicine
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• v.12 no.1
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• pp.44-48
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• 2015

Townes-Brocks syndrome (TBS) is a rare genetic disorder characterized by the classic triad of congenital anomalies of the anus, thumbs, and ears, with variable expressivity. Additionally, renal malformations, cardiac anomalies, and endocrine and eye abnormalities can accompany TBS, although less frequently. TBS is inherited in an autosomal dominant fashion; however, about 50% of patients have a family history of TBS and the remaining 50% have de novo mutations. SALL1, located on chromosome 16q12.1, is the only causative gene of TBS. SALL1 acts as a transcription factor and may play an important role in inducing the anomalies during embryogenesis. Clinical features of TBS overlap with those of other multiple anomaly syndromes, such as VACTERL syndrome, Baller-Gerold syndrome, Goldenhar syndrome, cat eye syndrome, and Holt-Oram syndrome. Consequently, there are some difficulties in differential diagnosis based on clinical manifestations. Herein, we report a Korean family with two generations of TBS that was diagnosed based on physical examination findings and medical history. Although the same mutation in SALL1 was identified in both the mother and the son, they displayed different clinical manifestations, suggesting a phenotypic diversity of TBS.

• Food Science of Animal Resources
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• v.34 no.6
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• pp.829-835
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• 2014

Inflammatory bowel disease (IBD) is caused by dysregulation of colon mucosal immunity and mucosal epithelial barrier function. Recent studies have reported that lipoteichoic acid (LTA) from Lactobacillus plantarum K8 reduces excessive production of pro-inflammatory cytokine. In this study, we investigated the preventive effects of lysate of Lb. plantarum K8 in dextran sulfate sodium (DSS)-induced colitis. Male Sprague-Dawley rats were orally pretreated with lysate of Lb. plantarum K8 (low dose or high dose) or live Lb. plantarum K8 prior to the induction of colitis using 4% DSS. Disease progression was monitored by assessment of disease activity index (DAI). Histological changes of colonic tissues were evaluated by hematoxylin and eosin (HE) staining. Tumor necrosis factor-alpha (TNF-${\alpha}$), interleukin-6 (IL-6) levels were measured using enzyme-linked immunosorbent assay (ELISA). The colon mRNA expressions of TNF-${\alpha}$, IL-6, and toll like receptor-2 (TLR-2) were examined by quantitative real-time-transcription polymerase chain reaction (qPCR). Lysate of Lb. plantarum K8 suppressed colon shortening, edema, mucosal damage, and the loss of DSS-induced crypts. The groups that received lysate of Lb. plantarum K8 exhibited significantly decreased levels of the pro-inflammatory cytokines TNF-${\alpha}$ and IL-6 in the colon. Interestingly, colonic expression of toll like receptor-2 mRNA in the high-dose lysate of Lb. plantarum K8 group increased significantly. Our study demonstrates the protective effects of oral lysate of Lb. plantarum K8 administration on DSS-induced colitis via the modulation of pro-inflammatory mediators of the mucosal immune system.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.16 no.4
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• pp.92-106
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• 2017

The adverse weather is known as a factor that interrupts traffic flow and causes traffic accidents and traffic congestion by lowering visibility of drivers. Especially, in case of fog unlike any other weather conditions, traffic accidents lead to serious accidents and the fatality of the accidents is known to be high. This paper aims to analyze uninterrupted traffic flow characteristics under foggy conditions among adverse weathers. The traffic volumes and speeds under foggy and normal conditions were analyzed. Results indicated that fog with low visibility causes the most insignificant reduction in traffic volumes. On the other hand, the reduction in the speeds due to low visibility was evident. In addition, the relationship between flow, speed, and density in fog were analyzed. Analysis results showed that the fog with less than 200m visibility had clear impact on traffic flow.

• Journal of Korean Academy of Nursing
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• v.50 no.4
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• pp.554-570
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• 2020

Purpose: This study aimed to develop and test a structural equation model of health-related quality of life among older women following bilateral total knee replacement based on a literature review and Wilson and Cleary's model of health-related quality of life. Methods: One hundred ninety three women who were diagnosed with osteoarthritis, were older than 65 years, and were between 13 weeks and 12 months of having a bilateral total knee replacement were recruited from an outpatient clinic. Data were collected from July 2017 to April 2018 using a structured questionnaire and medical records. Data were analyzed using SPSS/WIN 22.0, AMOS 22.0, and Smart PLS 3.2.4. Results: The fitness of the hypothetical model was good, with coefficients of determination (R²) ranging between .28 and .75 and predictive relevance (Q²) between .26 and .73. The standardized root mean square residual of the model fit indices for the hypothetical model was .04; which explained 64.2% of physical and 62.5% of mental health-related quality of life. Self-efficacy, symptom status, functional status, and general health perceptions had a significant direct effect on physical health-related quality of life, while social support, symptom status, and general health perceptions had a significant direct effect on participants' mental-health-related quality of life. Conclusion: To improve the physical and mental quality of life of older women who receive bilateral knee replacement, nursing-based intervention strategies that reduce symptoms, improve functional status, and increase health perceptions, self-efficacy, and social support are needed. The most important factor is the symptom status.

• International Journal of Concrete Structures and Materials
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• v.11 no.1
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• pp.85-97
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• 2017

Research has suggested that conventional lightweight concrete can offer durability advantages due to reduced cracking tendency. Although a number of publications exist providing the results of laboratory-based studies on the durability performance of lightweight concrete (with lightweight coarse aggregate) and internally cured concrete (using prewetted lightweight fine aggregate), far fewer field studies of durability performance of conventional lightweight concrete bridge decks in service have been performed. This study was commissioned to provide insight to a highway agency on whether enhanced durability performance, and therefore reduced maintenance and longer lifecycles, could be anticipated from existing lightweight concrete bridge decks that were not intentionally internally cured. To facilitate performance comparison, each lightweight bridge deck selected for inclusion in this study was paired with a companion normalweight bridge deck on a bridge of similar structural type, deck thickness, and geometric configuration, with similar age, traffic, and environmental exposure. The field-observed cracking of the decks was recorded and evaluated, and crack densities for transverse, longitudinal, and pattern cracking of the normalweight and lightweight deck in each pair were compared. Although some trends linking crack prevalence to geographic location, traffic, and age were observed, a distinct difference between the cracking present in the paired lightweight and normalweight bridge decks included in this study was not readily evident. Statistical analysis using analysis of covariance (ANCOVA) to adjust for age and traffic influence did not indicate that the type of concrete deck (lightweight or normalweight) is a statistically significant factor in the observed cracking. Therefore, for these service environments, lightweight decks did not consistently demonstrate reduced cracking.

• The Bulletin of The Korean Astronomical Society
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• v.41 no.1
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• pp.41.2-41.2
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• 2016

The follow-up BVRI photometric observations of NSVS 1461538, which was discovered as an $Algol/{\beta}$ Lyr eclipsing variable by Hoffman, Harrison & McNamara (2009), were performed for three years from 2011 to 2013 by using the 61-cm telescope and CCD cameras of Sobaeksan Optical Astronomy Observatory (SOAO). New light curves have deep depths both of the primary and secondary eclipses, rounded shapes outside eclipses and a strong O'Connell effect, indicating that NSVS 1461538 is a typical W UMa close binary system rather than an $Algol/{\beta}$ Lyr type binary star. A period study with all the timings shows that the orbital period may vary in a sinusoidal way with a period of about 5.6 yr and a small semi-amplitude of about 0.008 d. The cyclical period variation was interpreted as a light-time effect due to a tertiary body with a minimum mass of $0.66M{\odot}$. The first photometric solution with the Wilson-Devinney binary model shows that the system is a W-subtype contact binary with the mass ratio ($q=m_c/m_h$) of 3.46, orbit inclination of 85.6 deg and fill-out factor of 30%. From the existing empirical relationship between parameters, the absolute dimension was estimated. The masses and radii of the component stars are $0.28M{\odot}$ and $0.71R{\odot}$ for the less massive but hotter primary star, respectively, and $0.96M{\odot}$ and $1.21R{\odot}$ for the more massive secondary, respectively. Possible evolution of the system is discussed in the mass-radius and the mass-luminosity planes.

• Biomedical Science Letters
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• v.15 no.1
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• pp.31-35
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• 2009

High blood pressure (BP) is the most frequent risk factor among metabolic syndrome components. The control of hypertension is very important to prevent the cardiovascular risk in metabolic syndrome. The dysfunction of calcium channel is responsible in the regulation of the vascular muscle contribution to hypertension. Calcium channel, voltage-dependent, P/Q type, alpha-1A subunit (CACNA1A) gene is located in brain and known to control the intracranial hypertension. In this study, we investigate whether the polymorphisms of CACNA1A gene is associated with hypertension. The 49 CACNA1A genotypes were determined using the Affymetrix Genotyping chip array in 92 hypertension and 279 control individuals from a Korean population. Logistic and multiple regression models were employed to analyze the genetic contributions of polymorphisms. Out of 49 polymorphisms, six SNPs (rs12611029, rs16035, rs7259944, rs10419472, rs17777900, and rs4926294) showed a significant association with hypertension in three alternative models (codominant, dominant, and recessive models; P<0.05 after adjusting for age and sex). Our results suggest that the CACNA1A gene may be associated with hypertension in the Korean population.

• Journal of the Korean Institute of Telematics and Electronics
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• v.27 no.11
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• pp.9-19
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• 1990

A theoretical analysis and measurement technique to determine the complex permittivity and permeability of cylindrical and ring type dielectric resonators is given. The resonant frequency, unloaded quality factor and physical dimensions of dielectric resonator placed between two parallel conducting plates are used to evaluate the complex permittivity and permeability. This process is repeated for other higher-order modes to expand the evaluation at higher resonant frequencies. The nature of each mode is identified by measuring the variations of field strength along the azimuthal and longitudinal direction. An error analysis taking into account various error sources reveals that $TE_{0np}$ or quasi-TE modes yield the least amount of measurement error, which is less than $0.5{\%}$for the real part, $4{\%}$for the imaginary part of complex permittivity.