• Structural Engineering and Mechanics
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• v.70 no.2
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• pp.153-168
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• 2019

In this paper, energy absorption characteristics of circular windowed tubes with different section shapes (circular, ellipse, square, hexagon, polygon and pentagon) are investigated numerically and experimentally. The tube possesses the same material, thickness, height, volume and average cross sectional area which are subjected under axial and oblique quasi-static loading conditions. Numerical model was constructed with FE code ABAQUS/Explicit, the obtained outcome of simulation is in good matching with the experimental data. The energy absorbed, specific energy absorption, crash force efficiency, peak and mean loads along with the collapse modes with their initiation point of simple and windowed tubes were evaluated. The technique for order of preference by similarity ideal solution (TOPSIS) approach was employed for assessing their overall crushing performances. The obtained results confirm that efficacy of crash force indicators have improved by introducing windows and tubes with pentagonal and circular windows achieves the maximum ranking about 0.528 and 0.517, it clearly reveals the above are best window shapes.

• Asian Journal of Innovation and Policy
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• v.8 no.1
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• pp.73-96
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• 2019

This study suggests a new approach for identifying core robot tech-nologies based on technological cross-impact. Specifically, the approach applies data mining techniques and multi-criteria decision-making methods to the co-classification information of registered patents on the robots. First, a cross-impact matrix is constructed with the confidence values by applying association rule mining (ARM) to the co-classification information of patents. Analytic network process (ANP) is applied to the co-classification frequency matrix for deriving weights of each robot technology. Then, a technique for order performance by similarity to ideal solution (TOPSIS) is employed to the derived cross-impact matrix and weights for identifying core robot technologies from the overall cross-impact perspective. It is expected that the proposed approach could help robot technology managers to formulate strategy and policy for technology planning of robot area.

• Bulletin of the Korean Chemical Society
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• v.5 no.5
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• pp.194-198
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• 1984

The UV action spectra and quantum yields for photodestruction of tryptophan (Trp) in peptide such as N-acetylphenylalanyl-L-tryptophan (NAPT) and 3-methyl indole (scatole) were determined in aerated aqueous and organic solvents. The photodestruction of aqueous NAPT was shown to be initiated by photoionization without requirement of threshold energy, as demonstrated by the similarity of fluence effect curves obtained for the action at various wavelengths and the wavelength dependence of quantum yield comparable to that reported for the photoionization of L-Trp. N-formylkynurenine (NFK)-type photoproduct, which is a photodynamic sensitizer, was not found to be involved in the photodestruction of Trp in NAPT in aqueous solution. In contrast, the action spectra of NAPT and scatole in organic solvents have revealed evidences for the significant role of internal photosensitization by NFK-type photoproduct in photolysis of Trp in peptide.

• Journal of Information Processing Systems
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• v.17 no.3
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• pp.441-452
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• 2021

Federated learning provides an efficient integrated model for distributed data, allowing the local training of different data. Meanwhile, the goal of multi-task learning is to simultaneously establish models for multiple related tasks, and to obtain the underlying main structure. However, traditional federated multi-task learning models not only have strict requirements for the data distribution, but also demand large amounts of calculation and have slow convergence, which hindered their promotion in many fields. In our work, we apply the rank constraint on weight vectors of the multi-task learning model to adaptively adjust the task's similarity learning, according to the distribution of federal node data. The proposed model has a general framework for solving optimal solutions, which can be used to deal with various data types. Experiments show that our model has achieved the best results in different dataset. Notably, our model can still obtain stable results in datasets with large distribution differences. In addition, compared with traditional federated multi-task learning models, our algorithm is able to converge on a local optimal solution within limited training iterations.

• Architectural research
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• v.23 no.4
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• pp.67-73
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• 2021

An efficient demolition process requires the optimum method selection considering stability, economic feasibility, environment, and workability. In reality the construction cost and period are priority concerns, and safe construction methods are neglected. In addition, the choosing demolition method is often determined subjectively by experienced field engineers. This research paper presents a multi-criteria decision-making method using Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) to select the optimum demolition method. Three experienced demolition engineers' opinions were used to develop the TOPSIS model. The case study showed that the preferences of ten attribute measurements for demolition method selection. Authors suggested the most preferable demolition method for the case study project.

• Journal of applied mathematics & informatics
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• v.41 no.5
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• pp.973-988
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• 2023

In real-life scenarios, we may have to deal with real numbers or numbers in intervals or a combination of both to solve multi-criteria decision-making (MCDM) problems. Also, we may come across a situation where we must combine this interval and actual number membership values into a single real number. The most significant factor in combining these membership values into a single value is by using aggregation operators or scoring algorithms. To overcome such a situation, we suggest the cubic hypersoft set (CHSS) concept as a workaround. Ultimately, this makes it simple for the decision-maker to obtain information without misconceptions. The primary aim of this study is to establish some operational laws for the cubic hypersoft set, present the fundamental properties of aggregation operators and propose an algorithm by using the technique of order of preference by similarity to the ideal solution (TOPSIS) technique based on correlation coefficients to analyze the stress-coping skills of workers.

• Advances in concrete construction
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• v.17 no.1
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• pp.37-43
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• 2024

In this paper, boundary layer flow is observed through stretching cylinder exponentially with non-linear velocity. This cylinder is rested in porous medium. Appropriate similarity transformation is employed for the conversion of governing PDEs into ODEs. To compute the problem and solution series numerical method is applied and evaluated by using finite difference Keller-Box method. The velocity ratio, permeability parameter, Reynold number is figure out to examine the effect of on velocity profile. Fluid velocity and skin friction coefficient goes down with increment of Reynold number and permeability parameter. While reverse behavior is reported for velocity ratio. The results are validated with earlier investigations and found very well.

• The Mathematical Education
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• v.46 no.4
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• pp.371-388
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• 2007

This is a case study trying to understand from the view of affordance which certain three middle school students perceive an activation of previous knowledge in the course of problem solving when they solve algebra word problems with a previous knowledge. The results of this study showed that at first, every subjects perceived the text as affordance which explaining superficial similarities, that is, a working(painting)situation rather than problem structure and then activated the related solution knowledge on the ground of the experience of previous problem solving which is similar to current situation. The subject's applying process for solving knowledge could be arranged largely into two types. The first type is a numeral information connected with the described problem situation or a symbolic representation of mathematical meaning which are the transformed solution applied process with a suitable solution formula to the current problem. This process achieved by constructing a virtual mental model that indicating mathematical situation about the problem when the solver read the problem integrating symbolized information from the described text. The second type is a case that those subjects symbolizing a formal mathematical concept which is not connected with the problem situation about the described numeral information from the applied problem or the text of mathematical meaning, which process is the case to perceive superficial phrases or words that described from the problem as affordance and then applied previously used algorithmatical formula as it was. In conclusion, on the ground of the results of this case study, it is guessed that many students put only algorithmatical knowledge in their memories through previous experiences of problem solving, and the memories are connected with the particular phrases described from the problems. And it is also recognizable when the reflection process which is the last step of problem solving carried out in the process of understanding the problem and making a plan showed the most successful in problem solving.

• Nuclear Engineering and Technology
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• v.25 no.2
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• pp.193-203
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• 1993

A new heuristic method for loading pattern search has been developed to overcome short-comings of the algorithmic approach. To reduce the size of vast solution space, general shuffling rules, a regionwise shuffling method, and a pattern grouping method were introduced. The entropy theory was applied to classify possible loading patterns into groups with similarity between them. The pattern search program was implemented with use of the PROLOG language. A two-group nodal code MEDIUM-2D was used for analysis of power distribution in the core. The above mentioned methodology has been tested to show effectiveness in reducing of solution space down to a few hundred pattern groups. Burnable poison rods were then arranged in each pattern group in accordance with burnable poison distribution rules, which led to further reduction of the solution space to several scores of acceptable pattern groups. The method of maximizing cycle length(MCL) and minimizing power-peaking factor(MPF) were applied to search for specific useful loading patterns from the acceptable pattern groups. Thus, several specific loading patterns that have low power-peaking factor and large cycle length were successfully searched from the selected pattern groups.

• The Korean Journal of Rheology
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• v.11 no.2
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• pp.122-127
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• 1999

The characteristics of thermal boundary layer flow of a micropolar fluid in the vicinity of a wedge has been studied with constant surface temperature. The similarity variables found by Falkner and Skan are employed to reduce the streamwise-dependence in the coupled nonlinear boundary layer equations. Numerical solutions are presented for the heat transfer characteristics with Pr=1 using the fourth-order Runge-Kutta method and their dependence on the material parameters is discussed. The distributions of dimensionless temperature and Nusselt number across the boundary layer are compared with the corresponding flow problems for a Newtonian fluid over wedges. Numerical results show that for a constant wedge angle with a given Prandtl number, Pr=1, the effect of increasing values of K results in an increasing thermal boundary thickness for a micropolar fluid, as compared with a Newtonian fluid. For the case of the constant material parameter K, however, the heat transfer rate for a micropolar fluid is lower than that of a Newtonian fluid.