• Structural Engineering and Mechanics
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• v.67 no.5
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• pp.439-455
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• 2018

Within a probabilistic framework, this paper addresses the determination of the static structural response of beams and frames with partially restrained (semi-rigid) connections. The flexibility of the nodal connections is incorporated via an idealized linear-elastic behavior of the beam constraints through the use of rotational springs, which are here considered uncertain for taking into account the largely scattered results observed in experimental findings. The analysis is conducted via the Probabilistic Transformation Method, by modelling the spring stiffness terms (or equivalently, the fixity factors of the beam) as uniformly distributed random variables. The limit values of the Eurocode 3 fixity factors for steel semi-rigid connections are assumed. The exact probability density function of a few indicators of the structural response is derived and discussed in order to identify to what extent the uncertainty of the beam constraints affects the resulting beam response. Some design considerations arise which point out the paramount importance of probability-based approaches whenever a comprehensive experimental background regarding the stiffness of the beam connection is lacking, for example in steel frames with semi-rigid connections or in precast reinforced concrete framed structures. Indeed, it is demonstrated that resorting to deterministic approaches may lead to misleading (and in some cases non-conservative) outcomes from a design viewpoint.

• The Mathematical Education
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• v.50 no.1
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• pp.103-118
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• 2011

The study examined whether the relation between mathematics self-efficacy and mathematics achievement was partially mediated by the learning strategies, using latent growth model analyses. It was also examined the auto-regressive, cross-lagged (ARCL) panel model for testing the stability and change in the relation of mathematics self-efficacy and learning strategy over time. The study analyzed the first-year to the third-year data of the Korean Educational Longitudinal Survey (KELS). The result of ARCL panel model analysis showed that earlier mathematics self-efficacy could predict later learning strategy use. There were linear trends in mathematics self-efficacy, learning strategy, and mathematics achievement. Specifically, mathematics achievement was increased over the three time points, whereas mathematics self-efficacy and learning strategies were significantly decreased. In the analyses of latent growth models, the mediating effects of learning strategies were overall supported. That is, both of initial status and change rate of rehearsal strategy partially mediated the relation of mathematics self-efficacy and mathematics achievement. However, in elaboration and meta-cognitive strategies, only the initial status of each variable showed the indirect relationship.

• Korean Journal Plant Pathology
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• v.3 no.3
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• pp.198-202
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• 1987

Toxic metabolites ('Toxins'), produced by Helminthosporium sativum causing leaf blotch in barley and root rot in barley and wheat were partially purified through C-18 column. The partially purified toxins appeared heat unstable and lipophilic. The responses of toxins to wheat and barley root corresponded with those to lettuce growth with the different concentrations. The determination of the concentration of toxins produced was developed using the dilution end-points. The equation [Y = a log X + b) was obtained from the semi-log­graphy with the linear analysis. The values 'a' and 'b' were discussed with the responses of several plants on the toxin produced by H. sativum.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.19 no.3
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• pp.183-193
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• 2007

Analytic solutions are derived for wave scattering by a semi-infinite breakwater or a breakwater gap with partially reflective front and fully reflective back. The water depth is constant and a regular wave train is normally incident to the breakwater. Wave scattering is studied based on the linear potential wave theory. The governing equation is transformed into ordinary differential equation by using the method of variation of parameters and coordinate transformation. Comparison with finite element numerical solution shows that the analytic solution obtained in this paper gives quite good results. Using the analytic solution, the tranquility of harbor entrance is investigated by changing the reflection coefficient at the breakwater.

• Journal of the Korean Society of Food Culture
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• v.29 no.1
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• pp.101-110
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• 2014

This study was performed to determine the optimal composition of a muffin added with jerusalem artichoke powder and oligosaccharide. The experiment was designed based on CCD (central composite design), and evaluation was carried out by means of RSM (response surface methodology), which included 10 experimental points with three replicates each for the two independent variables jerusalem artichoke powder and oligosaccharide. The experimental muffin was prepared according to a traditional recipe, except that the flour was partially replaced by jerusalem artichoke powder (5, 15, or 25%) and the sugar was partially replaced by oligosaccharide (25, 50, or 75%). Using F-test, height, moisture, a-value, b-value, springiness, cohesiveness, texture, and overall acceptability were expressed as a linear model, whereas volume, pH, L-value, appearance, flavor and taste were expressed as a quadratic model. Increased amounts of jerusalem artichoke powder led to reduction of sensory scores for appearance, flavor, taste, texture, and overall quality. The optimum formulation determined by the numerical and graphical methods were similar: jerusalem artichoke powder 10.99%, oligosaccharide 71.40%.

• Journal of KSNVE
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• v.4 no.2
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• pp.163-175
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• 1994

An analytical method for nautral frequencies of a partially liquid- filled circular cylindrical shell with various boundary conditions is developed by means of the Stokes's transformation and Fourier series expansion on the basis of Sanders' shell equation. The liquid-shell coupled system is divided into two regions for convenient formulation. One is the empty shell region in which the Sanders' shell equations are formulated without the lipuid effect, the other is wetted shell region in which the shell equations are formulated with consideration of the liquid dynamic effect. The shell equations for each regions are combined by the geometry and the force continuities at the junction of the two regions. For the vibration relevant to the liquid motion, the velocity potential of liquid is assumed as a sum of linear combination of suitable harmonic functions in axial direction. The unknown parameters are selected to satisfy the boundary condition along the wetted shell surface. The natural frequencies of the liquid filled cylindraical shells with the clamped- free and the clamped-clamped boundary conditions examined in the previous works, are obtained by this analytical method. The results are compared with the previous works, and excllent agreement is found for the natural frequencies of the shells.

• Korean Journal of Child Studies
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• v.35 no.1
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• pp.119-133
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• 2014

The purpose of this study is to examine the effects of time perspective, self-control and cellular phone addiction on academic procrastination, and to cellular phone addiction has any mediating effects in relation to the effects of adolescents' time perspective and self-control on academic procrastination. For this study, a survey was conducted with total 651 students in middle and high schools. Those who omitted responses or answered in ways which were otherwise invalid were excluded and finally, questionnaires responded to by 558 students were analyzed. Employing SPSS Win 12.0, average value, standard deviation, frequency analysis, Pearson's correlation analysis, stepwise multiple regression analysis, and simple linear regression analysis were used for the purposes of statistical analysis. In conclusion, first, explanations were made in order of future-oriented time perspective which is subordinate domain of view of time perspective, self-control, and cellular phone addiction. Second, it was found that cellular phone addiction has partially mediating effect on the relationships between future-oriented time perspective which is a subordinate area of adolescents' time perspective, and academic procrastination. Third, it was found that cellular phone addiction has partially mediating effect on the relationships between adolescents' self-control and academic procrastination.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.12 no.7
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• pp.3172-3193
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• 2018

Recently, several studies have shown that linear representation based approaches are very effective and efficient for image classification. One of these linear-representation-based approaches is the Collaborative representation (CR) method. The existing algorithms based on CR have two major problems that degrade their classification performance. First problem arises due to the limited number of available training samples. The large variations, caused by illumintion and expression changes, among query and training samples leads to poor classification performance. Second problem occurs when an image is partially noised (contiguous occlusion), as some part of the given image become corrupt the classification performance also degrades. We aim to extend the collaborative representation framework under limited training samples face recognition problem. Our proposed solution will generate virtual samples and intra-class variations from training data to model the variations effectively between query and training samples. For robust classification, the image patches have been utilized to compute representation to address partial occlusion as it leads to more accurate classification results. The proposed method computes representation based on local regions in the images as opposed to CR, which computes representation based on global solution involving entire images. Furthermore, the proposed solution also integrates the locality structure into CR, using Euclidian distance between the query and training samples. Intuitively, if the query sample can be represented by selecting its nearest neighbours, lie on a same linear subspace then the resulting representation will be more discriminate and accurately classify the query sample. Hence our proposed framework model the limited sample face recognition problem into sufficient training samples problem using virtual samples and intra-class variations, generated from training samples that will result in improved classification accuracy as evident from experimental results. Moreover, it compute representation based on local image patches for robust classification and is expected to greatly increase the classification performance for face recognition task.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.12 no.2
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• pp.1-10
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• 1992

In this study, the 'Comb-structure' model which has been developed from truss analogy is modified in order to be applied to the shear analysis of partially prestressed concrete members. The proposed 'Comb-structure' model is modified so that the position, the slope of concrete compressive chord and the slope of concrete diagonal strut may change according to the magnitude of loads and prestress. For the proposed mechanical model, non-linear beam and truss elements are used. By modifying the 'Compression-Field' theory, the equation to determine the slope angle of concrete diagonal strut can be induced. The anaysis results by the proposed 'Comb-structure' model are compared with the experimental results and validity of model is examined. It shows that the the result of 'Comb-structure' analysis lies between that of the modified M$\ddot{o}$rsch theory and classical M$\ddot{o}$rsch theory, and close to the measured value after cracking. The deflection of the beam and the stress of stirrup show good agreement, so it can be concluded that the proposed 'Comb-structure' analysis model explains the shear behavior of partially prestressed concrte beams after crack initiation.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.21 no.5
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• pp.410-418
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• 2009

Based on a linear potential theory, the boundary element method(BEM) is developed and applied to analyze the hydrodynamic forces and the motion responses of a floating body with a partially reflective sidewall. The hydrodynamic forces (added mass and damping coefficients) are dependent on not only the submergence of a floating body and the reflection of a sidewall, but also the gap between body and sidewall. In particular, the partial reflection of a sidewall plays an importance role in the motion responses of a floating body at resonant frequencies. It reduces the resonant peaks caused by resonance phenomenon due to the wave trapping in an enclosed fluid domain between body and sidewall. Developed predictive tools can be used to assess the motion performance of a floating body for various combinations of configuration of a floating body, wave heading, sidewall properties, and wave characteristics and applied to supply the basic informations for the harbour design considering the motion characteristics of a moored ship.