• Communications for Statistical Applications and Methods
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• v.18 no.2
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• pp.245-255
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• 2011

There are two nonparametric methods that use empirical distribution functions and probability density estimators for the test of the distribution change of data. In this paper we investigate the two methods precisely and summarize the results of previous research. We assume several probability models to make a simulation study of the change point analysis and to examine the finite sample behavior of the two methods. Empirical powers are compared to verify which is better for each model.

• Journal of the Korean GEO-environmental Society
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• v.17 no.12
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• pp.65-72
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• 2016

There are numerous factors that affect stress distribution in a buried pipe, such as the shape, size, and stiffness of the pipe, its burial depth, and the stiffness of the surrounding soil. In addition, the pipe can benefit from the soil arching effect to some extent, through which the overburden and surcharge pressure at the crown can be carried by the adjacent soil. As a result, the buried pipe needs to support only a portion of the load that is not transferred to the adjacent soil. This paper presents numerical efforts to investigate the stress distribution in the buried concrete pipe under various environmental conditions. To that end, a nonlinear elasto-plastic model for backfill materials was implemented into finite element software by a user-defined subroutine (user material, or UMAT) to more precisely analyze the soil behavior surrounding a buried concrete pipe subjected to surface loading. In addition, three different backfill materials with a native soil were selected to examine the material-specific stress distribution in pipe. The environmental conditions considering in this study the loading effect and void effects were investigated using finite element method. The simulation results provide information on how the pressures are redistributed, and how the buried concrete pipe behaves under various environmental conditions.

• Journal of Ecology and Environment
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• v.42 no.1
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• pp.12-19
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• 2018

Background: The objective of this study was to determine the relationship between soil environmental factors and halophyte distribution in the west coast of South Korea. Soils of our study sites were categorized into two groups: salt marsh and estuary marsh. Results: Salinity was higher in the salt marsh group than that in the estuary marsh group. However, total nitrogen, silt, and clay contents were higher in the estuary marsh group than those in the salt marsh group. Although altitude had a wider range in the salt marsh group, the mean altitude was higher in the estuary marsh group than that in the salt marsh group. Annual halophytes of seed propagation species were distributed parallel to the coast line on salt marsh. Higher coverage of vegetation was found in the area closer to the coast line. Plant density was higher near dead parental plants in estuary marsh, showing less difference in area that was more distant from the coast line. Conclusions: Results of canonical correspondence analysis (CCA) for vegetation distribution and sediment environmental factors and germination analysis in the coast line showed significant relationship with halophyte distribution. Therefore, they can be used as an indicator of coastal plant movement due to sea level rise.

• Korean Journal of Optics and Photonics
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• v.17 no.2
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• pp.136-142
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• 2006

This paper presents irradiance distribution model of light radiated from a step-index multimode optical fiber. The model is important in analysis of displacement response characteristics for intensity modulation type optical fiber sensors. The induced model was verified by experimental results. And the displacement response analysis result induced by using the irradiance distribution model was verified by experimental results and compared with using existing irradiance distribution models such as the constant model or the gaussian model. The experiment has better agreement with the analysis result using the induced model in this study than with the others models.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.28 no.3
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• pp.26-35
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• 2005

This paper is intended to compare the hazard rate estimations from Bayesian approach and maximum likelihood estimate(MLE) method. Hazard rate frequently involves unknown parameters and it is common that those parameters are estimated from observed data by using MLE method. Such estimated parameters are appropriate as long as there are sufficient data. Due to various reasons, however, we frequently cannot obtain sufficient data so that the result of MLE method may be unreliable. In order to resolve such a problem we need to rely on the judgement about the unknown parameters. We do this by adopting the Bayesian approach. The first one is to use a predictive distribution and the second one is a method called Bayesian estimate. In addition, in the Bayesian approach, the prior distribution has a critical effect on the result of analysis, so we introduce the method using computerized-simulation to elicit an effective prior distribution. For the simplicity, we use exponential and gamma distributions as a likelihood distribution and its natural conjugate prior distribution, respectively. Finally, numerical examples are given to illustrate the potential benefits of the Bayesian approach.

• Journal of The Geomorphological Association of Korea
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• v.23 no.2
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• pp.61-70
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• 2016

This study intended to analyze the spatial distribution of two types of weeding song (Short Bang-a and Sangsa ryu) and how geomorphic elements influence the propagation of the songs in Chungcheongbuk-do area. The distribution of the two types of song was mapped as point data. According to the result, both types showed similar distribution pattern. In order to figure out the reason of this similarity, the distribution pattern of songs was analyzed at various scales based on geomorphic elements including river, mountain and lineament. The result showed that most of distribution pattern of songs followed the lineament direction. Also, the spatial continuity among mountain that was formed by large and small lineament in various directions could be the path of the cultural diffusion. If the lineament with same direction does not intersect other lineament that have different direction, spatial continuity would be blocked. Consequently it was confirmed that propagation of songs has not spread smoothly.

• Structural Engineering and Mechanics
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• v.56 no.2
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• pp.169-188
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• 2015

There are two types of nonlinear analysis methods for building frameworks depending on the method of modeling the plastification of members including lumped plasticity and distributed plasticity. The lumped plasticity method assumes that plasticity is concentrated at a zero-length plastic hinge section at the ends of the elements. The distributed plasticity method discretizes the structural members into many line segments, and further subdivides the cross-section of each segment into a number of finite elements. When a reinforced concrete member experiences inelastic deformations, cracks tend to spread form the joint interface resulting in a curvature distribution. The program IDARC includes a spread plasticity formulation to capture the variation of the section flexibility, and combine them to determine the element stiffness matrix. In this formulation, the flexibility distribution in the structural elements is assumed to be the linear. The main objective of this study is to evaluate the accuracy of linear flexibility distribution assumed in the spread inelasticity model. For this purpose, nonlinear analysis of two reinforced concrete frames is carried out and the linear flexibility models used in the elements are compared with the real ones. It is shown that the linear flexibility distribution is incorrect assumption in cases of significant gravity load effects and can be lead to incorrect nonlinear responses in some situations.

• Wind and Structures
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• v.19 no.4
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• pp.371-387
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• 2014

Probability plotting positions are popular and used as the basis for distribution fitting and for inspecting the quality of the fit because of its simplicity. The plotting positions that lead to excellent approximation to the mean of the order statistics should be used if the objective of the fitting is to estimate quantiles. Since the mean depends on the sample size and is not amenable for simple to use closed form solution, many plotting positions have been presented in the literature, including a new plotting position that is derived based on the weighted least-squares method. In this study, the accuracy of using the new plotting position to fit the Gumbel distribution for estimating quantiles is assessed. Also, plotting positions derived by fitting the mean of the order statistics for all ranks is proposed, and an approximation to the covariance of the order statistics for the Gumbel (and Weibull) variate is given. Relative bias and root-mean-square-error of the estimated quantiles by using the proposed plotting position are shown. The use of the proposed plotting position to estimate the quantiles of annual maximum wind speed is illustrated.

• Journal of Distribution Science
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• v.19 no.12
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• pp.71-81
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• 2021

Purpose: This study to seek to answer two research questions in distribution science: what photo decoration cues in online grocery stores could be identified? Could photo decoration cues significantly effect on the affective perception and behavioral intention of consumers? Research design, data, and methodology: his study conducted a laboratory experiment with a 2×2×2 factorial design to validate the proposed research model and test our proposed hypotheses. Research design, data and methodology: Two stages experiments were adopted in this study, among 360 voluntaries who have had an experience of online grocery shopping, 331 valid data had been collected and analyzed using MANOVA and PLS-SEM algorism. Results: (1) both reflective surface and complementary goods layout lead to visual appeal and shopping enjoyment; (2) contrast color usage positively impacts on visual appeal while does not significantly affect shopping enjoyment; (3) consumers' affective responses positively impact attitudes toward product and store which in turn lead to purchase intention and store loyalty. Implications for research and practice are discussed. Conclusions: Using the media richness theory, visual rhetoric theory and visual design literature as the theoretical foundation, the study provides a solid foundation to comprehend the impact of photo design artifacts on consumers' affective responses when online consumers shopping online for fresh grocery.

• Journal of Distribution Science
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• v.19 no.6
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• pp.51-64
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• 2021

Purpose: A restaurant is a business of the physical distribution of food and beverages which includes intercultural interaction. This research paper aims to examine the influence of Japanese taste as a product advantage, determining service quality factor in the restaurant business, the e-CRM that involves technology, social media campaigns to reach the target market of young people, and customer satisfaction on customer loyalty in Sushi Tei restaurant. This study also intends to find direct and indirect influence between the variables. Research design, data and methodology: Quantitative research was conducted using a survey method by distributing 100 questionnaires to Sushi Tei customers in Jakarta, consisting of Gen Z and Millennials. Samples were taken at each outlet in the Jakarta area on weekend and weekdays by purposive sampling. Data was generated by path analysis Results: The results showed that Japanese taste, service quality, and e-CRM significantly influence customer satisfaction and customer loyalty. However, social media campaigns failed to influence customer loyalty. As a result, customer satisfaction has a significant influence on customer loyalty within Sushi Tei restaurant. Conclusion: The study also proposed significant implications to develop and maintain a relationship with the customer to gain satisfaction and loyalty in the food and beverage industry.