• Title/Summary/Keyword: analytical study

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Measurement Uncertainty for Analytical Method of Hyaluronic Acid Used as a Dietary Supplement (식이보충제로 사용되는 히알루론산의 분석법에 대한 불확도 산정)

  • Park, Sang-Wook;Kim, Hyung Bum;Kim, Kwang Joon;Lee, Wonjae
    • KSBB Journal
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    • v.32 no.1
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    • pp.54-62
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    • 2017
  • This study aimed to estimate the measurement uncertainty related to determination of hyaluronic acid used as a dietary supplement by high-performance liquid chromatography. According to the guidelines of the Association of Official Analytical Chemists, the analytical processes for determination of hyaluronic acid were performed. And the measurement uncertainty obtained during the analytical processes were expressed in accordance with mathematical/ statistical guidances of GUM (Guide to the Expression of Uncertainty in Measurement) & EURACHEM (Focus for Analytical Chemistry in Europe) for the analytical operations. For the uncertainty in measurement produced based on this analytical method, the expanded uncertainty was calculated by using the relative standard uncertainty between analytical results and sources of uncertainty in measurement (sample weight, final volume, extraction volume, standard solution, matrix and instrument etc). In the results of 95% confidence interval, it was calculated that the uncertainty in measurement was $57.75{\pm}8.76{\mu}g/kg$ (k=2.0). Therefore, it showed that the measurement uncertainty obtained by this analytical method influences on 15.2% of the contents of hyaluronic acid as the analytical results.

The Effects of Student's Stress and Personal Relationship on Smart Phone Addiction

  • Kang, Gil-Hyun
    • Journal of the Korea Society of Computer and Information
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    • v.20 no.9
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    • pp.147-153
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    • 2015
  • This Study is to test the causal relationships among university student's stress, personal relationships and psychological anxiety, and then suggest some theoretical and policy implications basing on the analytical results. For the purpose of this study, survey targeting on 416 university students was conducted. The analytical results of this study showed that psychological anxiety moderates the relation between the stress, personal relationship and smart phone addiction. This study suggested some implications basing on this analytical results.

A Study of Analytical Sensitivity on TDM Test Kit in Clinical Chemistry (약물검사 키트의 분석 민감도에 대한 연구)

  • Chang, Sang Wu;Kim, Nam Yong;Lee, Hee Gyung;Kim, Hyun Jung;Lee, Yun Jung;Jin, Ok Bae;Kim, Mi Gyung
    • Korean Journal of Clinical Laboratory Science
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    • v.36 no.2
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    • pp.127-130
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    • 2004
  • Analytical sensitivity on TDM test is the lowest concentration that can be distinguished from background noise. The aim of study was to evaluate analytical sensitivity that is also referred to as the lower limit of detection(LLD) about difference between zero calibrator and isotonic saline sample. We tested for 10 days with zero calibrators and 0.85% saline samples while running trilevel control samples under control. Raw data divided by two groups calculated mean and standard deviation from two sample populations and analytical sensitivity by ${\bar{X}}+2SD$. In comparison with isotonic saline samples and zero calibrators, there were significant differences in phenytoin, phenobarbital and vancomycin, etc. Especially analytical sensitivity on phenytoin is at the same level as the upper limit of analytical measurement range with $40{\mu}g/mL$. We think the cause of this is matrix interference. In conclusion, we were sure that standard protocol for analytical sensitivity as lower limit of analytical measurement range on TDM test must be measured with zero standard rather than an isotonic saline sample and type 1 reagent DW for reducing matrix effects within interactions between different materials in a mixture.

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A Parametric Study on Effects of Column Shortening Analytical Correction Using Measured Results in RC Tall Buildings (RC 고층 건물에서 계측 결과를 이용한 기둥축소 해석보정의 효과에 대한 변수 연구)

  • Song, Eun-Seok;Kim, Jae-Yo
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.24 no.4
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    • pp.38-47
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    • 2020
  • A parametric study for analytical correction using measurement results was performed to minimize errors in the predictions of column shortening in RC tall building. The parameters of the column shortening analytical correction are the execution standard of analytical correction, the value of the analytical correction, and the measurement location, and the analytical correction models with the parameters were applied to the construction sequence analysis of a 41-story RC building to compare and analyze the correction effect according to the parameter. The reduction ratio of the error value for each floor was compared with the number of corrections and the total corrected value, and it was confirmed that the error tended to be minimized when the execution standard of analytical correction was performed based on a regular interval, when the analysis correction value was corrected by the error value, and when the measurement position was measured every floor. From this, it was confirmed that the most appropriate analytical correction model can be derived by applying multiple analytical correction models to the actual analysis model.

An analytical model for shear links in eccentrically braced frames

  • Ashtari, Amir;Erfani, Saeed
    • Steel and Composite Structures
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    • v.22 no.3
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    • pp.627-645
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    • 2016
  • When an eccentrically braced frame (EBF) is subjected to severe earthquakes, the links experience inelastic deformations while beams outside of the link, braces and columns are designed to remain elastic. To perform reliable inelastic analyses of EBFs sufficient analytical model which can accurately predict the inelastic performance of the links is needed. It is said in the literature that available analytical models for shear links generally predict very well the maximum shear forces and deformations from experiments on shear links, but may underestimate the intermediary values. In this study it is shown that available analytical models do not predict very well the maximum shear forces and deformations too. In this study an analytical model which can accurately predict both maximum and intermediary values of shear force and deformation is proposed. The model parameters are established based on test results from several experiments on shear links. Comparison of available test results with the hysteresis curves obtained using the proposed analytical model established the accuracy of the model. The proposed model is recommended to be used to perform inelastic analyses of EBFs.

The Role of Imagery vs. Analytical Advertisement on New Products Evaluation

  • Lee, Juyon;Chu, Wujin
    • Asia Marketing Journal
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    • v.22 no.2
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    • pp.59-85
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    • 2020
  • Combining prior theories on innovation newness with information processing style (imagery vs. analytical), this study presents a theoretical framework; develops hypotheses; and makes predictions on how analytical versus imagery ads influence consumers differently depending on the newness level of products. The study shows that consumers are more likely to evaluate RNPs (radically-innovative new products) positively when they are advertised with imagery cues. Compared with analytical advertisements, imagery advertisements increased advertising effectiveness, product evaluation, and purchase intention of RNPs. These effects were demonstrated by using stimuli from two product categories consisting of washing machines and cars. In particular, in advertisement for RNPs, verbal description that induced imagery processing, such as "picture yourself using this product," was more effective in generating favorable responses, compared to verbal description that induced analytical processing, such as explanation of product attributes. This difference was present for RNPs, but not for INPs (incrementally-innovative new products). INPs are continuous innovations that are easier to understand, thus imagery ads do not provide additional advantage for consumers in understanding the innovation, compared to analytical ads. In RNPs, imagery ads can highlight new benefits that may have been neglected or undervalued by consumers, leading to greater message persuasiveness. Implications for marketing of RNPs are discussed.

Analytical and numerical study of temperature stress in the bi-modulus thick cylinder

  • Gao, Jinling;Huang, Peikui;Yao, Wenjuan
    • Structural Engineering and Mechanics
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    • v.64 no.1
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    • pp.81-92
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    • 2017
  • Many materials in engineering exhibit different modulus in tension and compression, which are known as bi-modulus materials. Based on the bi-modulus elastic theory, a modified semi-analytical model, by introducing a stress function, is established in this paper to study the mechanical response of a bi-modulus cylinder placed in an axisymmetric temperature field. Meanwhile, a numerical procedure to calculate the temperature stresses in bi-modulus structures is developed. It is proved that the bi-modulus solution can be degenerated to the classical same modulus solution, and is in great accordance with the solutions calculated by the semi-analytical model proposed by Kamiya (1977) and the numerical solutions calculated both by the procedure complied in this paper and by the finite element software ABAQUS, which demonstrates that the semi-analytical model and the numerical procedure are accurate and reliable. The result shows that the modified semi-analytical model simplifies the calculation process and improves the speed of computation. And the numerical procedure simplifies the modeling process and can be extended to study the stress field of bi-modulus structures with complex geometry and boundary conditions. Besides, the necessity to introduce the bi-modulus theory is discussed and some suggestions for the qualitative analysis and the quantitative calculation of such structure are proposed.

Validation of an analytical method for cyanide determination in blood, urine, lung, and skin tissues of rats using gas chromatography mass spectrometry (GC-MS)

  • Shin, Min-Chul;Kwon, Young Sang;Kim, Jong-Hwan;Hwang, Kyunghwa;Seo, Jong-Su
    • Analytical Science and Technology
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    • v.32 no.3
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    • pp.88-95
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    • 2019
  • This study was conducted to establish the analytical method for the determination of cyanide in blood, urine, lung and skin tissues in rats. In order to detect or quantify the sodium cyanide in above biological matrixes, it was derivatized to Pentafluorobenzyl cyanide (PFB-CN) using pentafluorobenzyl bromide (PFB-Br) and then reaction substance was analyzed using gas chromatography mass spectrometer (GC/MS)-SIM (selected ion monitoring) mode. The analytical method for cyanide determination was validated with respect to parameters such as selectivity, system suitability, linearity, accuracy and precision. No interference peak was observed for the determination of cyanide in blank samples, zero samples and lower limit of quantification (LLOQ) samples. The lowest limit detection (LOD) for cyanide was $10{\mu}M$. The linear dynamic range was from 10 to $200{\mu}M$ for cyanide with correlation coefficients higher than 0.99. For quality control samples at four different concentrations including LLOQ that were analyzed in quintuplicate, on six separate occasions, the accuracy and precision range from -14.1 % to 14.5% and 2.7 % to 18.3 %, respectively. The GC/MS-based method of analysis established in this study could be applied to the toxicokinetic study of cyanide on biological matrix substrates such as blood, urine, lung and skin tissues.

Analysis and Alternative Circuit Design of Pneumatic Circuit for An Automotive Air Suspension (자동차 공기현가 공압회로 해석 및 대체회로 설계)

  • Lee, J.C.
    • Transactions of The Korea Fluid Power Systems Society
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    • v.5 no.4
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    • pp.17-25
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    • 2008
  • This study presents an analytical model of the pneumatic circuit of an air suspension system to analyze the characteristics of vehicle height control. The analytical model was developed through the co-simulation of Simulink(air spring) and HyPneu(pneumatic circuit). Variant effective area of air spring and flow coefficients of pneumatic valves were estimated experimentally prior to the system test, and utilized in simulation. One-comer test apparatus was established using the components of commercial air suspension products. The results of simulation and experiment were so close that the proposed analytical model in this study was validated. However the frictional loss of conduit and heat dissipation which were ignored in this study need to be considered in future study. As an application example of proposed analytical model, an alternative pneumatic circuit of air suspension to conventional WABCO circuit was evaluated. The comparison of simulation results of WABCO circuit and alternative circuit show that proposed analytical model of co-simulation in this study is useful for the study of pneumatic system of automotive air suspension.

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Comparative study of analytical models of single-cell tornado vortices based on simulation data with different swirl ratios

  • Han Zhang;Hao Wang;Zhenqing Liu;Zidong Xu;Boo Cheong Khoo;Changqing Du
    • Wind and Structures
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    • v.36 no.3
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    • pp.161-174
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    • 2023
  • The analytical model of tornado vortices plays an essential role in tornado wind description and tornado-resistant design of civil structures. However, there is still a lack of guidance for the selection and application of tornado analytical models since they are different from each other. For single-cell tornado vortices, this study conducts a comparative study on the velocity characteristics of the analytical models based on numerically simulated tornado-like vortices (TLV). The single-cell stage TLV is first generated by Large-eddy simulations (LES). The spatial distribution of the three-dimensional mean velocity of the typical analytical tornado models is then investigated by comparison to the TLV with different swirl ratios. Finally, key parameters are given as functions of swirl ratio for the direct application of analytical tornado models to generate full-scale tornado wind field. Results show that the height of the maximum radial mean velocity is more appropriate to be defined as the boundary layer thickness of the TLV than the height of the maximum tangential mean velocity. The TLV velocity within the boundary layer can be well estimated by the analytical model. Simple fitted results show that the full-scale maximum radial and tangential mean velocity increase linearly with the swirl ratio, while the radius and height corresponding to the position of these two velocities decrease non-linearly with the swirl ratio.