• Journal of Electrical Engineering and Technology
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• v.10 no.1
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• pp.30-40
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• 2015

For a shunt power quality controller (SPQC) the DC side voltage value which is closely related to the compensation performance is a significant parameter. Buy so far, very little discussion has been conducted on this in a quantitative manner by previous publications. In this paper, a method to design the DC side voltage of SPQC is presented according to the compensation performance in the single-phase system and the three-phase system respectively. First, for the reactive current and the harmonic current compensation, a required minimal value of the DC side voltage with a zero total harmonic distortion (THD) of the source current and a unit power factor is obtained for a typical load, through the equivalent circuit analysis and the Fourier Transform analytical expressions. Second, when the DC side voltage of SPQC is lower than the above-obtained minimal value, the quantitative relationship between the DC side voltage and the THD after compensation is also elaborated using the curve diagram. Hardware experimental results verify the design method.

• Journal of the Korea Safety Management & Science
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• v.7 no.1
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• pp.57-76
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• 2005

A standardized ergonomics kit is suggested to evaluate and reduce musculoskeletal hazards that yield large socioeconomic burdens in the work system. This kit comprises basic and detailed analysis tools with proper tool selection rules. The basic tool includes a checklist for various risk factors to screen potentially hazardous jobs among manual works. Selective detailed analysis tools can then be applied to the screened job lists for more quantitative and precise evaluation. The tool selection rules are devised for using the basic and detailed analysis tools in a mutually supplemental way. To validate the standardized ergonomics kit, it was applied to evaluate jobs related to the musculoskeletal hazards in a paper-making industry. Among 101 manual jobs investigated, 44 potential hazardous jobs were screened during basic investigation phase and finally 16 hazardous jobs were identified by the detailed analysis phase. The result provided fairly promising ideas of ergonomic interventions for the hazardous jobs.

• Korean Journal of Pharmacognosy
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• v.48 no.1
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• pp.88-92
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• 2017

In the present study, we carried out quantitative analysis of chrysin and pinocembrin in Korean propolis by ultra performance liquid chromatography (UPLC) equipped with diode array detector. The separation was done using BEH C18 ($2.1{\times}50mm$, $1.7{\mu}m$) column with a mobile phase consisting of MeCN and 0.1% $H_3PO_4$ at 280 nm. The chromatographic method was validated for specificity, limit of detection, limit of quantification, linearity, precision, and accuracy. A quantitative analysis exhibited that the contents of the two compounds in Korean propolis collected from 8 inland areas except Jeju-do ranged from 3.1-46.0 mg/g. These results will be valuable as basic data for standardization of Korean propolis.

• Journal of the Korean Society for Heat Treatment
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• v.16 no.1
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• pp.10-15
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• 2003

In Nb, V and Ti added steels, carbo-nitrides are formed due to their strong interaction with C and N. The formation of carbo-nitrides has an important role to control the microstructure as well as mechanical properties by grain size refinement and precipitation hardening. However, the quantitative analysis of distribution of precipitates and the effect of precipitates on the phase transformation and mechanical properties are still far from satisfactory. In this study, the quantitative analysis of precipitates in austenite was investigated using the fact that the formation of precipitates in Nb, V and Ti added steels accelerates austenite/ferrite transformation. The formation of precipitates was controlled by adjusting holding temperature and time in austenite region, transformed Volume fractions were measured by dilatometer during slow cooling, Iso-precipitation kinetics were determined by comparing 5% and 50% volumes transformed at various conditions respectively. The result was compared with the calculated.

• Korean Journal of Pharmacognosy
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• v.42 no.1
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• pp.15-21
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• 2011

Scrophulariae Radix (Scrophulariaceae) has been traditionally used to treat pharyngitis, laryngitis, tonsillitis, fever, and edema. To compare the quality of the Scrophulariae Radix produced from Gyeongbuk with that from China, a quantitative analysis on the major component, E-harpagoside, was performed by reversed-phase HPLC, and a relative inhibitory activity of nitric oxide (NO) was assayed in the Raw 264.7 cells. Using a Luna $C_{18}$(2) column, we carried out quantitative analysis with a gradient of 0.1% phosphoric acid in water and acetonitrile. Our results demonstrated that the content of E-harpagoside in Gyeongbuk's Scrophulariae Radix were three times higher than that of Chinese. Moreover, the inhibitory activity of Scrophulariae Radix of Gyeongbuk's in the lipopolysaccharide (LPS)-induced NO production was higher than that of Chinese.

• Natural Product Sciences
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• v.20 no.3
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• pp.182-190
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• 2014

An ultra-performance liquid chromatography (UPLC) coupled with electrospray ionization (ESI) tandem mass spectrometry (MS) method was established for quantitative analysis of twelve components, allantoin (1), morroniside (2), 5-hydroxymethyl-2-furfural (5-HMF) (3), loganin (4), coumarin (5), cinnamic acid (6), mesaconitine (7), cinnamaldehyde (8), hypaconitine (9), aconitine (10), alisol B (11), and alisol B acetate (12) in a Palmijihwang-hwan decoction. The twelve constituents were separated on a UPLC BEH C18 column ($2.1{\times}100mm$, $1.7{\mu}m$) at a column temperature of $40^{\circ}C$ by gradient elution with 0.1% (v/v) formic acid in water and acetonitrile as the mobile phase. The flow rate was 0.3 mL/min and the injection volume was $2.0{\mu}L$. Calibration curves of all compounds were acquired with values of the correlation coefficient ${\geq}0.99$ within the test ranges. The limits of detection and quantification for all analytes were 0.01 - 4.53 ng/mL and 0.03 - 13.60 ng/mL, respectively. The concentrations of the compounds 1 - 9 and 12 were 72.83, 4389.00, 4859.00, 3155.17, 223.67, 33.50, 1.97, 518.00, 2.25, and $25.00{\mu}g/g$, respectively. However, compounds 10 and 11 were not detected.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.9 no.1
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• pp.71-78
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• 1998

Type Ⅰ thyuroplasty in conjunction with arytenoid adduction is one of the excellent techniques in the treatment of unilateral vocal fold paralysis. But perioperative objective evaluation of the patients is difficult. With the development of the videostroboscopy and image analysis program, we could quantify the Glottal Area Waveform(GAW) in patients with unilateral vocal fold paralysis and investigated the relationship between the glottal area and aerodynamic and acoustic parameters. Eight female patients who were performed type Ⅰ thyroplasty in conjunction with arytenoid adduction and 5 females with normal vocal function were involved in this study. Preoperative and postoperative videostroboscopy and vocal function study wire performed. GAW was analysed quantitatively with image analysis program (Kay Stroboscope Image analysis, KSIP) Peak Glottal Area(PGA), Baseline Offset(BO), and Closing Phase(CP) were increased in patients with unilateral vocal fold paralysis and they were reduced after the operation. Mean flow Rate (MFR) was well correlated with the PGA in normal control group and unilateral vocal fold paralysis patients. Noise to harmonic ratio(NHR) was correlated with PGA only in preoperative unilateral vocal fold paralysis patients. In conclusion quantitative measurement of the GAW is useful method in evaluation of unilateral vocal f31d paralysis patients.

• Journal of the Korean Society for Precision Engineering
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• v.15 no.11
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• pp.121-129
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• 1998

In-plane ESPI(Electronic Speckle Pattern Interferometry) was devised to measure in-plane deformations and rotation of a specimen with laser in this study. ESPI is a optical measuring method to be able to measure the deformations of engineering components and materials in industrial fields. The conventional measuring methods of surface deformations such as the strain gauge have many demerits because they are contact and point-to-point measuring ones. But that ESPI is noncontact, nondestructive and whole field measuring method can overcome previous disadvantages. We used ESPI which is sensitive to in-plane displacement for measuring in-plane deformations of a disk. And the 4-frame phase shifting method was used for the quantitative analysis. First of all, the system calibration was done due to an in-plane rotation before getting deformations of a disk. Finally we showed good agreement between the experiment results and those of the FEA(Finite Element Analysis).

• Bulletin of the Korean Chemical Society
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• v.30 no.1
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• pp.137-144
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• 2009

In this study, quantitative and pattern recognition analyses for the quality evaluation of Herba Epimedii using HPLC was developed. For quantitative analysis, five major bioactive constituents, hyperin, epimedin A, epimedin B, epimedin C, and icariin were determined. Analysis was carried out on Capcell pak $C_{18}$ column ($250{\time}4.6$ mm, 5 ${\mu}m$) with a mobile phase of mixture of acetonitrile and 0.1% formic acid, using UV detection at 270 nm. The linear behavior was observed over the investigated concentration range (2-50 ${\mu}g/mL;\;r_2\;>$ 0.99) for all analytes. The intraand inter-day precisions were lower than 4.3% (as a relative standard deviation, RSD) and accuracies between 95.1% and 104.4%. The HPLC analytical method for pattern recognition analysis was validated by repeated analysis of one reference sample. The RSD of intra- and inter-day variation of relative retention time (RRT) and relative peak area (RPA) of the 12 selected common peaks were below 0.8% and 4.7%, respectively. The developed methods were applied to analysis of twenty Herba Epimedii extract samples. Contents of hyperin, epimedin A, epimedin B, epimedin C, and icariin were calculated to be 0$\sim$0.79, 0.69$\sim$1.91, 0.93$\sim$9.58, 0.65$\sim$3.05, and 2.43$\sim$11.8 mg/g dried plant. Principal component analysis (PCA) showed that most samples were clustered together with the reference samples but several apart from the main cluster in the PC score plot, indicating differences in overall chemical composition between two clusters. The present study suggests that quantitative determination of marker compounds combined with pattern-recognition method can provide a comprehensive approach for the quality assessment of herbal medicines.

• Korean Institute of Interior Design Journal
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• v.24 no.5
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• pp.117-127
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• 2015

This paper depicts a case study of the BIM (Building Information Modeling)-enabled evaluation of design alternatives for an actual remodeling project in Yeongwol, Korea. The increase of urban population and income followed by the growth of economy has derived massive supply of grand scale housing project in Korea since 1970s. Consequently, building remodeling became one of the feasible resolutions for renovating such old housings in these days. This paper aims to introduce a technical approach to such remodeling projects based on BIM-enabled applications focusing on quantitative analysis of design alternatives. Among the technical issues of such building remodeling projects, this paper focuses on the BIM-enabled area analysis and comparison between design alternatives to support decision-making even in early phase of remodeling design process. BIM and its variety of applications have broadly influenced the domain of AEC-FM (Architecture, Engineering, Construction, and Facility Management) within the lifecycle of buildings. As one of the applications facilitated by BIM, the automated area calculation and scenario-based comparison between alternatives can play an important role in the early phase of remodeling project. We modeled three design alternatives (buildings) and three housing modules (units) based on the actual case in Yeongwol city, Korea using a BIM design authoring tool. Nine combinatorial BIM models were demonstrated for the BIM-enabled review process described in this paper. To determine the most optimal design scenario among nine alternatives, this paper demonstrates a result of the conducted spatial program review. The main subject includes specific spatial program issues on; 1) the number of unit spaces; and 2) area of individual/grouped and private/shared spaces.