• Analytical Science and Technology
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• v.35 no.5
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• pp.218-227
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• 2022

A simple and fast throughput flow injection (FI) system with a merging-zone technique was designed to determine ferrous and ferric in an aqueous solution. The method is based on the direct reaction of ferrous with a Bathophenanthroline reagent (Bphen) in acidic media. The forming red complex absorbs light at 533 nm. All conditions of the flow injection system were investigated. The analytical curve of ferrous was linear in the range of 0.07 to 4 mg/L with an r² value of 0.9968. The detection and quantification limits were 0.02 and 0.04 mg/L, respectively. The molar absorptivity and Sandell's sensitivity were 4.0577 × 10⁶ L/mol cm and 25 × 10^-5 ㎍/cm², respectively. The homemade valve was low-cost with high repeatability (n = 7) at an RSD of 1.26 % and zero dead volume. The values of the dispersion coefficient were 2.318, 2.022, and 1.636 for the concentrations of 0.2, 1, and 3 mg/L, respectively. The analysis throughput of the designed flow injection unit was 57 sample per hour.

• International Journal of Computer Science & Network Security
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• v.23 no.7
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• pp.101-108
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• 2023

Decision Support Systems (DSS) is an Information Systems (IS) application that aids in decision-making processes for many business concepts and Customer Relationship Management (CRM) is one of them and it depends on the firm's tasks for developing and retaining customers while achieving their satisfaction and enhancing the sense of belongingness for their products and services. Profit maximization, the process of customer value, and building strategic values for the firm are the three empirical benefits of CRM that are achieved through analytical, operational, and direction (AOD) capabilities respectively. This research focuses on the application of DSS models of what-if analysis (WIA) for CRM at (AOD) and also shows the dependence on the Information Success model (ISM). Hypothetical data are analyzed for (AOD) by three types of (WIA) to attain CRM and profit maximization and this analytical method can be used by any customer-oriented firm as a general model and for the purpose of the study we have compared the CRM between patients and hospital management.

• Structural Engineering and Mechanics
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• v.84 no.3
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• pp.361-373
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• 2022

This paper examines the flexural performance of concrete beams reinforced with glass fibre-reinforced polymer (GFRP) bars under fatigue loading. Experiments were carried out on concrete beams of size 1500×200×100 mm reinforced with 10 mm and 13 mm diameter GFRP bars under fatigue loading. Experimental investigations revealed that fatigue loading affects both strength and serviceability properties of GFRP reinforced concrete. Experimental results indicated that (i) the concrete beams experienced increase in deflection with increase in number of cycles and failed suddenly due to snapping of rebars and (ii) the fatigue life of concrete beams drastically decreased with increase in stress level. Analytical model presented a procedure for predicting the deflection of concrete beams reinforced with GFRP bars under cyclic loading. Deflection of concrete beams was computed by considering the aspects such as stiffness degradation, force equilibrium equations and effective moment of inertia. Nonlinear finite element (FE) analysis was performed on concrete beams reinforced with GFRP bars. Appropriate constitutive relationships for concrete and GFRP bars were considered in the numerical modelling. Concrete non linearity has been accounted through concrete damage plasticity model available in ABAQUS. Deflection versus number of cycles obtained experimentally for various beams was compared with the analytical and numerical predictions. It was observed that the predicted values are comparable (less than 20% difference) with the corresponding experimental observations.

• Structural Engineering and Mechanics
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• v.89 no.1
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• pp.77-91
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• 2024

During strong seismic events, inelastic shear deformation occurs in beam-column joints. To capture inelastic shear deformation, an analytical model for beam-column joint in reinforced concrete (RC) frame structures has been proposed in this study. The proposed model has been developed using a rotational spring and rigid links. The stiffness properties of the rotational spring element have been assigned in terms of a moment rotation curve developed from the shear stress-strain backbone curve. The inelastic rotation behavior of joint has been categorized in three stages viz. cracking, yielding and ultimate. The joint shear stress and strain values at these stages have been estimated using analytical models and experimental database respectively. The stiffness properties of joint rotational spring have been modified by incorporating a geometry factor based on dimensions of adjoining beam and column members. The hysteretic response of the joint rotational spring has been defined by a pivot hysteresis model. The response of the proposed analytical model has been verified initially at the component level and later at the structural level with the two actually tested RC frame structures. The proposed joint model effectively emulates the inelastic behavior precisely with the experimental results at component as well as at structural levels.

• Coupled systems mechanics
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• v.13 no.3
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• pp.247-275
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• 2024

The paper studies the influence of the fluid flow velocity and flow direction in the initial state on the dispersion of the axisymmetric waves propagating in the inhomogeneously pre-stressed hollow cylinder containing this fluid. The corresponding eigenvalue problem is formulated within the scope of the three-dimensional linearized theory of elastic waves in bodies with initial stresses, and with linearized Euler equations for the inviscid compressible fluid. The discrete-analytical solution method is employed, and analytical expressions of the sought values are derived from the solution to the corresponding field equations by employing the discrete-analytical method. The dispersion equation is obtained using these expressions and boundary and related compatibility conditions. Numerical results related to the action of the fluid flow velocity and flow direction on the influence of the inhomogeneous initial stresses on the dispersion curves in the zeroth and first modes are presented and discussed. As a result of the analyses of the numerical results, it is established how the fluid flow velocity and flow direction act on the magnitude of the influence of the initial inhomogeneous stresses on the wave propagation velocity in the cylinder containing the fluid.

• Proceedings of the KIEE Conference
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• 2002.07b
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• pp.900-902
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• 2002

This paper deals with reduction of torque ripple of slotless PM linear synchronous motor (PMLSM) with divided permanent magnet using 2D analytical method. To confirm the validity of this study, analysis values by analytical method are comprared with the results of 2D FEM and experimental results. And the results of divided PM model is compared with none divided PM model.

• JSTS:Journal of Semiconductor Technology and Science
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• v.12 no.4
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• pp.473-481
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• 2012

For a mesa-isolated small geometry SOI MOSFET, the potentials in the silicon film, front, back, and side-wall oxide layers can be derived three-dimensionally. Using Taylor's series expansions of the trigonometric functions, the derived potentials are written in terms of the natural length that can be determined by using the derived formula. From the derived 3-D potentials, the minimum values of the front and the back surface potentials are derived and used to obtain the closed-form expressions for the front and back gate threshold voltages as functions of various device parameters and applied bias voltages. Obtained results can be found to explain the drain-induced threshold voltage roll-off and the narrow width effect of a fully depleted small geometry SOI MOSFET in a unified manner.

• Bulletin of the Society of Naval Architects of Korea
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• v.9 no.1
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• pp.15-20
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• 1972

As the technique of resistance spot welding became more and more advanced the factors hitherto considered secondary become more and more important. Among these factors the distribution of heat and temperature during resistance spot welding is particularly important in conjunction with thermal stress, strain and residual stress, strain problems. The analytical investigations upon the transient temperature due to resistance spot welding were made for the carbon steel plate and aluminum alloy plate. The numerical values obtained by the analytical investigation are nearly identical with the temperature distribution which obtained by D.J. Sullivan and some other experimental data. It was thought therefore useful to estimate the heat effect upon the material such as a residual stress and strain, metalurgical change, change in physical properties and etc.

• Analytical Science and Technology
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• v.11 no.2
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• pp.130-134
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• 1998

Polyamines were analyzed in young cotyledons of spring radish. The uptake rate of SPD were transported within 20 min lineary and reached the saturation phase after 1hr. The uptake rate of SPD decreased gradually with the time by the increasing amount of SPD inside the cells. The uptake of PA depends on the external pH. The optimal pH of PA uptake are pH 7.5. $K_m-$ and $V_{max}-$values depend on external pH also. The uptake rate of PA was inhibited by external KCI, which depolarized membrane potential in the cells.

• Proceedings of the KSRS Conference
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• 2005.10a
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• pp.233-235
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• 2005

This paper presents an unsupervised change detection methodology designed for the detection of landslide areas. The proposed methodology consists of two analytical steps: one for multi-temporal segmentation and the other for automatic selection of thresholding values. By considering the conditions of landslide occurrences and the spectral behavior of multi-temporal remote sensing images, some specific procedures are included in the analytical steps mentioned above. The effectiveness and applicability of the methodology proposed here were illustrated by a case study of the Gangneung area, Korea. The case study demonstrated that the proposed methodology could detect about $83\%$ of landslide occurrences.