• Smart Structures and Systems
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• v.20 no.1
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• pp.61-74
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• 2017

One of the most reliable and simplest tools for structural vibration control in civil engineering is Tuned Mass Damper, TMD. Provided that the frequency and damping parameters of these dampers are tuned appropriately, they can reduce the vibrations of the structure through their generated inertia forces, as they vibrate continuously. To achieve the optimal parameters of TMD, many different methods have been provided so far. In old approaches, some formulas have been offered based on simplifying models and their applied loadings while novel procedures need to model structures completely in order to obtain TMD parameters. In this paper, with regard to the nonlinear decision-making of fuzzy systems and their enough ability to cope with different unreliability, a method is proposed. Furthermore, by taking advantage of both old and new methods a fuzzy system is designed to be operational and reduce uncertainties related to models and applied loads. To design fuzzy system, it is required to gain data on structures and optimum parameters of TMDs corresponding to these structures. This information is obtained through modeling MDOF systems with various numbers of stories subjected to far and near field earthquakes. The design of the fuzzy systems is performed by three methods: look-up table, the data space grid-partitioning, and clustering. After that, rule weights of Mamdani fuzzy system using the look-up table are optimized through genetic algorithm and rule weights of Sugeno fuzzy system designed based on grid-partitioning methods and clustering data are optimized through ANFIS (Adaptive Neuro-Fuzzy Inference System). By comparing these methods, it is observed that the fuzzy system technique based on data clustering has an efficient function to predict the optimal parameters of TMDs. In this method, average of errors in estimating frequency and damping ratio is close to zero. Also, standard deviation of frequency errors and damping ratio errors decrease by 78% and 4.1% respectively in comparison with the look-up table method. While, this reductions compared to the grid partitioning method are 2.2% and 1.8% respectively. In this research, TMD parameters are estimated for a 15-degree of freedom structure based on designed fuzzy system and are compared to parameters obtained from the genetic algorithm and empirical relations. The progress up to 1.9% and 2% under far-field earthquakes and 0.4% and 2.2% under near-field earthquakes is obtained in decreasing respectively roof maximum displacement and its RMS ratio through fuzzy system method compared to those obtained by empirical relations.

• Analytical Science and Technology
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• v.31 no.4
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• pp.171-178
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• 2018

Recently, for successful lactation, many breastfeeding mothers seek various products, including herbal medicine, dietary supplements, and prescribed medicines, to improve milk production. As demand for galactogogues grows, it is highly possible that pharmaceutical galactogogues may be adulterated with illegal products to maximize their efficacy. For continuous control and supervision of illegal products, we developed and validated a simple and sensitive LC-MS/MS method capable of simultaneously determining five galactogogues. Chromatographic separation was conducted using an Agilent Poroshell $120SB-C_{18}$ column with a mobile phase consisting of 20 mM ammonium formate (pH 5.4) and 100 % acetonitrile. The total run time was 13 min per analyte. The proposed method was performed according to the guidelines of the International Conference of Harmonization and it produced reliable results. This method showed high sensitivity and specificity, with a limit of detection (LOD) and limit of quantitation (LOQ) of 0.01-0.82 ng/mL and 0.02-2.45 ng/mL, respectively, for the solid- and liquid-type samples. Specificity was evaluated by analyzing matrix-blank samples spiked with the target compounds at LOQ levels, which provided a good separation of all peaks without interference. Additionally, the repeatability and intermediate precision were typically <15 %, whereas the recovery was 80-120 % of the values obtained using blank samples. Thus, we concluded that this method could be used for the identification and quantification of galactogogues in food or herbal products.

• The Journal of Korean Academy of Prosthodontics
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• v.43 no.3
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• pp.363-378
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• 2005

Statement of problem. Hydroxyapatite(HA) coated titanium surfaces have not yet showed the reliable osseointegration in various conditions. Purpose. This study was aimed to investigate microstructures, chemical composition, and surface roughness of the surface coated by the hydrothermal method and to evaluate the effect of hydrothermal coating on the cell attachment, as well as cell proliferation. Material and Methods. Commercially pure(c.p.) titanium discs were used as substrates. The HA coating on c.p. titanium discs by hydrothermal method was performed in 0.12M HCl solution mixed with HA(group I) and 0.1M NaOH solution mixed with HA(group II). GroupⅠ was heated at 180 $^{\circ}C$ for 24, 48, and 72 hours. GroupⅡ was heated at 180 $^{\circ}C$ for 12, 24, and 36 hours. And the treated surfaces were evaluated by Scanning electron microscopy(SEM), Energy dispersive X-ray spectroscopy(EDS), X-ray photoelectron spectroscopy(XPS), X-ray diffraction method(XRD), Confocal laser scanning microscopy(CLSM). And SEM of fibroblast and 3-(4,5- dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide(MTT) assay were used for cellular responses of the treated surfaces. Results. The color of surface changed in both groups after the hydrothermal process. SEM images showed that coating pattern was homogeneous in group II, while inhomogeneous in group I. H72 had rosette-like precipitates. The crystalline structure grew gradually in group II, according to extending treatment period. The long needle-like crystals were prominent in N36. Calcium(Ca) and phosphorus(P) were not detected in H24 and H48 in EDS. In all specimens of group II and H72, Ca was found. Ca and P were identified in all treated groups through the analysis of XPS, but they were amorphous. Surface roughness did not increase in both groups after hydrothermal treatment. The values of surface roughness were not significantly different between groups I and II. According to the SEM images of fibroblasts, cell attachments were oriented and spread well in both treated groups, while they were not in the control group. However, no substantial amount of difference was found between groups I and II. Conclusions. In this study during the hydrothermal process procedure, coating characteristics, including the HA precipitates, crystal growth, and crystalline phases, were more satisfactory in NaOH treated group than in HCl treated group. Still, the biological responses of the modified surface by this method were not fully understood for the two tested groups did not differ significantly. Therefore, more continuous research on the relationship between the surface features and cellular responses seems to be in need.

• Culinary science and hospitality research
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• v.15 no.4
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• pp.286-298
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• 2009

The purpose of this study is to determine potential associations among consumer preference for American beef, consumers' involvement in selection of desired beef, and their intentions to purchase beef. In order to meet the above purpose, this study surveyed the visitors who shopped at 2 big discount stores selected in each of 3 metropolitan cities(Seoul, Daejeon and Daegu) from July 11 to 13, 2008. Total 278 sheets of the questionnaire were collected and used for final data analysis. As a result, it was found that the consumers responded most sensitively to the safety of food when buying beef but didn't care much about the amount of fat and beef brand. In terms of imported beef, it was found that Australian beef was considered reliable by consumers, and their preference for Korean beef was positively correlated with that for Australian beef. In addition, in regard to the attributes of beef selection, it was found that low involvement group had higher intentions to purchase American beef than high involvement group. In order to determine the potential effects of consumers' involvement in the attributes of beef selection on their intentions to purchase American beef, this study conducted data analysis in control of consumer preference for American beef. As a result, it was found that consumers' involvement in the attributes of beef selection had significant effects on their intentions to buy American beef. And sex was found to be one of the demographic characteristics associated with involvement in the attributes of beef selection, particularly associated with low involvement. Depending on sex, it was found that women had lower preference for American beef than men.

• Sleep Medicine and Psychophysiology
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• v.11 no.2
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• pp.84-88
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• 2004

Objectives: Obstructive sleep apnea (OSA) syndrome is diagnosed through history, physical examination, imaging studies and polysomnography. Clinical examination of this condition may point to hypertrophic tonsils and crowded oropharynx. The objective of this study is to investigate the usefulness of modified Mallampati grade (MMG) and tonsil grade (TG) in predicting the severity of obstructive sleep apnea. Methods: MMG and TG were divided into 4 and 5 groups, respectively, according to their severity. Medical records were collected from 94 patients who had received polysomnography and otorhinolaryngologic examination for snoring and sleep apnea at Keimyung University Dongsan Medical Center from March 2002 through April 2004. Patients were divided into two groups according to the apnea-hypopnea index (AHI)：control (n=24), and patients with sleep apnea (n=70). Results: Patients with higher MMG and TG had higher AHI, and MMG and TG proved to have a statistically significant correlation with AHI (p<0.05) Conclusion: MMG and TG were reliable predictors of OSA and helpful parameters in deciding treatment method.

• Journal of the Korean Data and Information Science Society
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• v.27 no.6
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• pp.1609-1619
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• 2016

The aim of this study was to identify the construct validity and reliability of a Korean version of the Wellness Evaluation of Lifestyle (K-WEL). A total of 345 nursing students completed the 99-item K-WEL. Construct validity using exploratory and confirmatory factor analysis were conducted using SPSS WIN 22.0 and AMOS 18.0. The final K-WEL consisted of 71 scored items, 14 subscales (self worth, work, spirituality, gender identity, love, friendship, realistic belief, leisure, exercise, nutrition, stress management, emotional responsiveness, sense of control, sense of humor) and 4 factors (essential, social, physical and coping self). Goodness of fit of the final research model was acceptable as shown by ${\chi}^2=225.12$, p<.001, CMIN/DF=3.17, RMSEA=.08, NFI=.87, IFI=.91, CFI=.91. The convergent validity and discriminant validity was evaluated by AVE (.61~.69) and C.R. (.79~.89). The Cronbach's alpha values were .55~.87 for the subscales of K-WEL. This study shows that the K-WEL is a valid and reliable measurement to assess multidimensional aspects of wellness.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.38 no.3
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• pp.477-485
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• 2018

To control manage environmental load during construction work, it is required to ascertain an accurate quantity for materials those are using during the construction. In construction industrial nowadays, especially on design part, there are lots of mistakes occurred on quantity take-off between plan documents and actual work. That mistakes are caused by omission of design items, overcount because of interference each materials or simple calculate error. Besides, in case of a construction project, engineers are impossible to design perfectly due to a lot of invalid variable in a construction site. Thus, design errors and changes occur frequently in the process of construction work or design due to such unclear elements. And in case of LCA assessment based on 2D design, there is difficult for an engineer who is in charge to calculate the volume of materials manually using drawings and relevant specifications. This study is aimed for examining and verifying a high reliable method of evaluating environmental load which is useful in construction process through comparing LCA analysis. In addition, this study provides the method of calculating the volume of materials and LCA assessment in working on the basis of 2D design, using the specifications which is used for LCA evaluation, and possibility of utilizing the LCA assessment by introducing BIM design technic to improve the former problem through comparing and analyzing the previous method with 3D-based evaluation process.

• The Korean Journal of Nuclear Medicine
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• v.9 no.2
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• pp.13-22
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• 1975

The purpose of the present study is to evaluate the diagnostic value of the ETR test as compared to other thyroid function tests in normal persons, patients with thyroid disorders and patients with alterations of thyroxine-binding proteins. The ETR values were obtained from 35 cases as normal control, 63 hyperthyroid patients, 56 euthyroid patients, 23 hypothyroid patients, 10 pregnant women, 5 women taking oral contraceptive medication, 8 liver cirrhosis patients and 4 nephrotic syndrome patients. The results obtained were as follows. 1. The mean value of ETR obtained from the normal controls was $0.99{\pm}0.06$. 2. The mean ETR values of various thyroid states were $1.25{\pm}0.16$ in hyperthyroidism, $0.99{\pm}0.08$ in euthyroidism and $0.82{\pm}0.05$ in hypothyroidism and significant difference was found between these groups. 3. Seven out of 63 hyperthyroid patients(11.1%) and 2 out of 23 hypothyroid patients(8.7%) had ETR values within normal range and among the 56 euthyroid patients 6(10.7%) had ETR values outside normal range, so the diagnostic compatibility of ETR was 89.4% in thyroid diseases. 4. Even though the ETR value was well correlated with $^{131}I$-thyroid uptake rate, serum $T_3$ resin uptake rate and serum $T_4$, a high positive correlation was found (r=0.79) between ETR and $T_7$. 5. The mean ETR values from patients with alteration in TBG binding capacity were $0.99{\pm}0.05$ in pregnant women, $0.98{\pm}0.04$ in women with oral contraceptive medication, $1.04{\pm}0.09$ in liver cirrhosis patients and $0.94{\pm}0.02$ in nephrotic syndrome patients and most of them (85.2%) had ETR values within normal range. Our results, therefore, suggests that the ETR estimation does offer the simplest and most reliable single procedure for the screening and diagnosis of various thyroid diseases as a indirect indicator of serum-free thyroxine concentration without essential influence of changes in the thyroxine-binding proteins in serum.

• Journal of Veterinary Clinics
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• v.27 no.6
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• pp.627-630
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• 2010

The aim of this study is to investigate neutrophil activation markers among canine ICU (intensive care unit) control, systemic inflammatory response syndrome (SIRS) and sepsis. These markers include WBC (white blood cells), platelets counts, blood film examination (neutrophilic band to segmentation ratio and neutrophilic degenerative changes), and flow cytometric analysis (CD11b expression of neutrophils). As a result, the mean CD11b fluorescence intensity of neutrophils and the neutrophilic degenerative change scores were both significantly higher in sepsis group (P<0.05). In addition, mortality was also found to be correlated with the up-regulation of CD11b expression in circulating neutrophils. This study demonstrates that CD11b expression of neutrophils could be more a reliable biomarker to predict prognosis in ICU patients than traditional blood film examination according to this study.

• The Korean Journal of Mycology
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• v.47 no.4
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• pp.437-441
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• 2019

Verticillium wilt disease is caused by a fungal plant pathogen Verticillium dahliae, which attacks commercial crops such as chrysanthemum. The conventional methods so far used to identify this fungal pathogen require high expertise and are time-consuming. Therefore, in this study, we developed an assay for the rapid and specific detection of V. dahliae infection using loop-mediated isothermal amplification (LAMP) method. For this assay, four primers for LAMP were designed for targeting cellulose-growth-specific protein partial mRNA gene in Verticillium dahliae. Under standard condition, the optimum reaction temperature for amplification is around 60 ℃ within 60 minutes. This LAMP assay was designed to amplify only present in V. dahliae. When this LAMP assay applied to the DNAs for four other soil-borne fungi and host plants, no amplification was detected. Therefore, this LAMP assay we developed for V. dahliae is expected to do detection at the early stage of its infection. The fast and reliable detection method will allow us to develop effective management system to monitor and control infection of this pathogen in chrysanthemum plant.