• 한국구조물진단유지관리공학회 논문집
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• 제24권4호
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• pp.38-47
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• 2020

RC 고층건물에서 발생하는 기둥축소의 예측 오차를 최소화하기 위하여 계측결과를 이용한 해석보정에 대한 변수연구가 수행되었다. 해석보정의 변수는 해석보정 시행기준, 해석보정 값, 계측 위치이며, 변수에 따른 해석보정 모델을 41층 규모의 RC 건물의 시공단계해석에서 적용하여 변수에 따른 보정 효과를 비교·분석하였다. 보정 횟수와 전체 보정량에 따른 층별 오차 값의 감소율을 비교하였으며, 해석보정의 시행기준은 일정한 간격을 기준으로 해석보정 할 경우, 해석보정 값은 오차 값만큼 보정할 경우, 계측 위치는 매 층 계측이 될 경우에 오차가 최소화되는 경향을 확인하였다. 이로부터 실제 해석 모델에 대하여 여러 해석보정 모델을 적용함으로써 가장 적합한 해석보정 모델을 도출할 수 있음을 확인하였다.

• Structural Engineering and Mechanics
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• 제72권4호
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• pp.491-502
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• 2019

This paper explores the analytical buckling solution of rectangular thin plates by the finite integral transform method. Although several analytical and numerical developments have been made, a benchmark analytical solution is still very few due to the mathematical complexity of solving high order partial differential equations. In solution procedure, the governing high order partial differential equation with specified boundary conditions is converted into a system of linear algebraic equations and the analytical solution is obtained classically. The primary advantage of the present method is its simplicity and generality and does not need to pre-determine the deflection function which makes the solving procedure much reasonable. Another advantage of the method is that the analytical solutions obtained converge rapidly due to utilization of the sum functions. The application of the method is extensive and can also handle moderately thick and thick elastic plates as well as bending and vibration problems. The present results are validated by extensive numerical comparison with the FEA using (ABAQUS) software and the existing analytical solutions which show satisfactory agreement.

• Journal of Magnetics
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• 제21권1호
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• pp.110-114
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• 2016

Magnetic couplings are widely used in various industrial applications because they can transmit magnetic force without any mechanical contact. In addition, linear couplings have many advantages. For example, they do not need to convert rotary motion to linear motion. This paper shows an analytical analysis of tubular type linear magnetic couplings (TLMCs) with a Halbach array magnetized permanent magnet (PM). An analytical method for magnetic fields owing to PMs is performed by using magnetic vector potential as well as Poisson and Laplace equations. Then, the magnetic force is calculated by using the Maxwell stress tensor. The analytical analysis results were compared with finite element method (FEM) results. In addition, we predicted the magnetic force characteristic according to design parameters such as the iron core thickness, inner PM thickness to -outer PM thickness ratio, PM segment ratio of the axial magnetized PM segment and radial magnetized PM segment, and various pole numbers.

• Steel and Composite Structures
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• 제24권6호
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• pp.697-709
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• 2017

The current study addresses the local buckling analysis of an infinite thin rectangular symmetrically laminated composite plate restrained by a tensionless Winkler foundation and subjected to uniform in-plane shear loading. An analytic method (i.e., one-dimensional mathematical method) is used to achieve the analytical solution estimate of the contact buckling coefficient. In addition, to study the effect of ply angle and foundation stiffness on the critical buckling coefficients for the laminated composite plates, the parametric studies are implemented. Moreover, the convergence for finite element (FE) mesh is analysed, and then the examples in the parametric study are validated by the FE analysis. The results show that the FE analysis has a good agreement with the analytical solutions. Finally, an example with the analytical solution and FE analysis is presented to demonstrate the availability and feasibility of the presented analytical method.

• Mass Spectrometry Letters
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• 제7권2호
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• pp.31-40
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• 2016

The analysis of nuclear materials and environmental samples is an important issue in nuclear safeguards and nuclear forensics. An analysis technique for safeguard samples has been developed for the detection of undeclared nuclear activities and verification of declared nuclear activities, while nuclear forensics has been developed to trace the origins and intended use of illicitly trafficked nuclear or radioactive materials. In these two analytical techniques, mass spectrometry has played an important role in determining the isotope ratio of various nuclides, contents of trace elements, and production dates. These two techniques typically use similar analytical instruments, but the analytical procedure and the interpretation of analytical results differ depending on the analytical purpose. The isotopic ratio of the samples is considered the most important result in an environmental sample analysis, while age dating and impurity analysis may also be important for nuclear forensics. In this review, important aspects of these techniques are compared and the role of mass spectrometry, along with recent progress in related technologies, are discussed.

• Mass Spectrometry Letters
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• 제9권4호
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• pp.105-109
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• 2018

A certified reference material (CRM) for the analysis of inorganic nutrients in nutritional supplements has been developed. Accurate mass fractions of chromium (Cr), iron (Fe), copper (Cu), and zinc (Zn) were determined by isotope dilution inductively coupled plasma mass spectrometry (ID ICP/MS). The measurement results were used to assign certified values for the CRM, which were metrologically traceable to the definitions of the measurement units in the International System of Units (SI). Production of a candidate reference material (RM) and the certification processes are summarized. Each nutrient in the CRM showed good homogeneity, which was estimated using relative standard deviations of the measurement results of twelve bottles in a batch. This CRM is expected to be an important reference to improve reliability and comparability of nutrient analyses in nutritional supplements and related samples in analytical laboratories.

• Mass Spectrometry Letters
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• 제12권3호
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• pp.85-92
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• 2021

The therapeutic antibody drug market has experienced explosive growth as mAbs become the main therapeutic modality for a variety of diseases. Characterization of glycosylation that directly affects the efficacy and safety of therapeutic monoclonal antibodies (mAbs) is critical for therapeutics development, bioprocess system optimization, lot release, and comparability evaluation. The LC/MS approach has been widely used to structurally characterize mAbs, and recently attempts have been made to obtain comprehensive information on the primary structure and post-translational modifications (PTMs) of mAbs through intact protein analysis. In this study, we performed state-of-the-art LC/MS based intact protein analysis to readily identify and characterize glycoforms of various mAbs. Different glycoforms of mAbs produced in different expression cell lines including CHO, SP2/0 and HEK cells were monitored and compared. In addition, the comparability of protein molecular weight, glycoform pattern, and relative abundances of glycoforms between the commercialized trastuzumab biosimilar and the original product was determined in detail using the given platform. Intact mAb analysis allowed us to gain insight into the overall mAb structure, including the complexity and diversity of glycosylation. Furthermore, our analytical platform with high reproducibility is expected to be widely used for biopharmaceutical characterization required at all stages of drug development and manufacturing.

• Structural Engineering and Mechanics
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• 제31권2호
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• pp.137-152
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• 2009

Mechanic behavior of Y-shape thin-walled box girder bridge structure is complex, so one can not exactly hold the mechanical behavior of the Y-shape thin-walled box girder bridge structure through general calculation theory and analytical method. To hold the mechanical behavior better, based on elementary beam theory, by increasing the degree of freedom analytical method, taking account of restrained torsiondistortion angledistortion warp and shearing lag effect at the same time, authors obtain a thin-walled box beam analytical element of 10 degrees of freedom of every node, derive stiffness matrix of the element, and code a finite element procedure. In addition, authors combine the obtained procedure with spatial grillage analytical method, meanwhile, they build a new analytical method that is the spatial thin-walled box girder element grillage analysis method. In order to validate the precision of the obtained analysis method, authors analyze a type Y-shape thin-walled box girder bridge structure according to the elementary beam theory analytical method, the shell theory analytical method and the spatial thin-walled box girder element grillage analysis method respectively. At last, authors test a type Y-shape thin-walled box girder bridge structure. Comparisons of the results of theory analysis with the experimental text show that the spatial thin-walled box girder element grillage analysis method is simple and exact. The research results are helpful for the knowledge of the mechanics property of these Y-shape thin-walled box girder bridge structures.

• Geomechanics and Engineering
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• 제8권6호
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• pp.769-781
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• 2015

The skin friction of a pile foundation is important and essential for its design and analysis. More attention has been given to the softening behaviour of skin friction of a pile. In this study, to investigate the load-transfer mechanism in such a case, an analytical solution using a nonlinear softening model was derived. Subsequently, a load test on the pile was performed to verify the newly developed analytical solution. The comparison between the analytical solution and test results showed a good agreement in terms of the axial force of the pile and the stress-strain relationship of the pile-soil interface. The softening behaviour of the skin friction can be simulated well when the pile is subjected to large loads; however, such behaviour is generally ignored by most existing analytical solutions. Finally, the effects of the initial shear modulus and the ratio of the residual skin friction to peak skin friction on the load-settlement curve of a pile were investigated by a parametric analysis.

• 식품과학과 산업
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• 제51권1호
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• pp.16-25
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• 2018

Recently, the importance of analytical techniques related to food safety is emerging in the food industry due to changes in diet patterns, environmental changes, climate change and consumer's interest in food safety. In particular, food safety accidents in the food industry may cause economic losses such as media reports, product recalls, consumer distrust, and so on. Therefore, a systematic, proactive and comprehensive food safety management system is increasingly required to prevent food safety issues. Efforts to ensure the reliability of food safety are essential by introducing various analysis instruments such as LC, GC, ICP, LC/MS/MS, GC/MS/MS, ICP/MS, PCR, and RT-PCR. In addition, recent food safety analytical techniques used in food industry should be shifted paradigm by developing multi-component simultaneous analytical method, low cost with high efficient analytical method, and eco-friendly method.