• Journal of Korean Society for Geospatial Information Science
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• v.14 no.4 s.38
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• pp.61-70
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• 2006

This paper presents photogrammetric processing to generate digital elevation models using SPOT-5 HRG stereo images and deals with the accuracy potential of HRG (High Resolution Geometry) supermode imagery for DEM generation. After bundle adjustment was preformed for sensor modelling, digital surface models were generated through the procedures of Epipolar image resampling and image matching. The DEM extracted from HRG imagery was compared along several test sections with the the refernce DEM which was obtained from the digital topographic maps of a scale of 1 to 5000. The ratio of the zone with DEM errors less than 5m to the whole zone was 53.8%, and about 2.5m RMSE was showed when assuming that the zones larger than 5m were affected by clouds, water bodies and buildings and excluding those zones from accuracy evaluation. In addition, the three-dimensional bird's eye view model and 3D building model were producted based on the DSM which was extracted from SPOT-5 HRG data.

• Geomechanics and Engineering
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• v.19 no.6
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• pp.499-511
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• 2019

The reliability of reinforced concrete structures is frequently compromised by the deterioration caused by reinforcement corrosion. Evaluating the effect caused by reinforcement corrosion on structural behaviour of corrosion damaged concrete structures is essential for effective and reliable infrastructure management. In lifecycle management of corrosion affected reinforced concrete structures, it is difficult to correctly assess the lifecycle performance due to the uncertainties associated with structural resistance deterioration. This paper presents a stochastic deterioration modelling approach to evaluate the performance deterioration of corroded concrete structures during their service life. The flexural strength deterioration is analytically predicted on the basis of bond strength evolution caused by reinforcement corrosion, which is examined by the experimental and field data available. An assessment criterion is defined to evaluate the flexural strength deterioration for the time-dependent reliability analysis. The results from the worked examples show that the proposed approach is capable of evaluating the structural reliability of corrosion damaged concrete structures.

• Journal of Agricultural Extension & Community Development
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• v.23 no.1
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• pp.1-14
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• 2016

The purpose of this study was to examine the relationships among experience, perceived value, and satisfaction of rural tourists based on the experience economy(Pine, & Gilmore, 1998; 1999). In addition, this study included the moderating effect of length of stay on the proposed relationships. This study was attempt to develop measurement scales based on the theory of experience economy(Pine, & Gilmore, 1998). Data were collected from 481 visitors by field survey from the 10 rural tourism communities. SPSS 20.0 and Amos 18.0 statistical package were used for frequency, reliability, confirmatory factor, and structural equation modelling analysis. The results of a confirmatory factor analysis yielded four dimensions of experience(esthetics, education, escape, and entertainment). The results of structural equation modeling indicated that entertainment, esthetics, and education had positive effects on perceived value, which in turn had a positive effect on satisfaction. In addition, length of stay moderated the relationships among experience, perceived value, and satisfaction. The entertainment and esthetics among experience factor had an effects on perceived value in the group of day visit group, and the entertainment, education, and esthetics among experience factor had an effects on perceived value in the group of stay night group. And the perceived value had a positive effect on satisfaction in the all group. Therefore, in order to increase rural tourists' satisfaction effectively, practitioners needs to develop rural tourism products by considering area of experience economy including tourists' length of stay.

• Journal of the Korean Society for Precision Engineering
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• v.28 no.3
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• pp.285-291
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• 2011

The error motion of a machine tool spindle directly affects the surface errors of machined parts. The error motions of the spindle are not desired errors in the three linear direction motions and two rotating motions. Those are usually due to the imperfect of bearings, stiffness of spindle, assembly errors, external force or unbalance of rotors. The error motions of the spindle have been needed to be decreased to desired goal of spindle's performance. The level of error motion is needed to be estimated during the design and assembly process of the spindle. In this paper, the estimation method for the five degree of freedom (5 D.O.F) error motions of the spindle is suggested. To estimate the error motions of the spindle, waviness of shaft and bearings, external force model was used as input data. And, the estimation models are considering geometric relationship and force equilibrium of the five degree of the freedom. To calculate error motions of the spindle, not only imperfection of the shaft, bearings, such as rolling element bearing, hydrostatic bearing, and aerostatic bearing, but also driving elements such as worm, pulley, and direct driving motor systems, were considered.

• The Korean Journal of Applied Statistics
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• v.30 no.2
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• pp.215-231
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• 2017

The US presidential primaries take place sequentially in different places with a time lag. However, they have not attracted as much attention in terms of modelling as the US presidential election has. This study applied several autologistic models to find the relation between the outcome of the primary election for a Democrat candidate with socioeconomic attributes in consideration of spatial and temporal dependence. According to the result applied to the 2016 election data at the county level, Hillary Clinton was supported by people in counties with high population rates of old age, Black, female and Hispanic. In addition, spatial dependence was observed, representing that people were likely to support the same candidate who was supported from neighboring counties. Positive auto-correlation was also observed in the time-series of the election outcome. Among several autologistic models of this study, the model specifying the effect of Super Tuesday had the best fit.

• Korean Journal of Child Studies
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• v.24 no.1
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• pp.99-108
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• 2003

This study was based on theories of the culture of poverty and the causes and consequences of poverty. The strong relationship of family income to mother's education presents the possibility of an intergenerational education cycle. Using a longitudinal approach, parental poverty status was measured by family income, welfare assistance, single parent, and occupation when children were 2 years of age; children's school performance was measured by teacher reports of their reading, mathematics, writing, and overall ability at grade 1. Data were analyzed by structure equation modeling. Results showed that mother's pre-childbearing level of education predicted child school performance in grade 1, confirming an intergenerational cycle. In addition, the results indicated that parental poverty acts as a mediator between the cycle.

• Advances in aircraft and spacecraft science
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• v.6 no.6
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• pp.529-550
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• 2019

The effect of multiple process parameters on a set of continuous response variables is, especially in experimental designs, difficult and intricate to determine. Due to the complexity in aeroacoustic and vibroacoustic studies, the often-performed simple one-factor-at-a-time method turns out to be the least effective approach. In contrast, the statistical Design of Experiments is a technique used with the objective to maximize the obtained information while keeping the experimental effort at a minimum. The presented work aims at giving insights on Design of Experiments applied to aeroacoustic and vibroacoustic problems while comparing different experimental designs and approximation models. For this purpose, an experimental rig of a ducted low-pressure fan is developed that allows gathering data of both, aerodynamic and aeroacoustic nature while analysing three independent process parameters. The experimental designs used to sample the design space are a Central Composite design and a Box-Behnken design, both used to model a response surface regression, and Latin Hypercube sampling to model an Artificial Neural network. The results indicate that Latin Hypercube sampling extracts information that is more diverse and, in combination with an Artificial Neural network, outperforms the quadratic response surface regressions. It is shown that the Latin Hypercube sampling, initially developed for computer-aided experiments, can also be used as an experimental design. To further increase the benefit of the presented approach, spectral information of every experimental test point is extracted and Artificial Neural networks are chosen for modelling the spectral information since they show to be the most universal approximators.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.10 no.6
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• pp.89-98
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• 2015

The purpose of this study was to investigate the effect of the Government's entrepreneurial support policy(educational support, financial support and marketing support) on entrepreneurship and entrepreneurial intention. This study examined educational support, fund support and marketing support as the The Government's entrepreneurial support polity variables and innovativeness, progressiveness and risk-taking as entrepreneurship variables. The sample of this study was composed of 331 existing and potential entrepreneurs selected from the national panel of a online web survey research firm. Data were collected using self-administerd structured questionnaires and analyzed employing structural equation modelling techniques. This study found that three entrepreneurship variables(innovativeness, progressiveness and risk-taking) had positive direct effects on entrepreneurial intention and that three Government's entrepreneurial support policy variables (educational support, financial support and marketing support) had positive direct effects on entrepreneurship, whereas these three variables had positive indirect effects on entrepreneurial intention. The theoretical and practical implications of the findings were discussed and the directions for future research were suggested.

• Korean Membrane Journal
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• v.8 no.1
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• pp.1-12
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• 2006

In semiconductor industries, dissolved oxygen is one of the most undesirable contaminants of ultrapure water. A method for dissolved oxygen removal (DOR) consists in the use of polymeric hollow fibres, loaded with a catalyst and fed with a reducing agent such as hydrogen. In this work, PVDF hollow fibres loaded with Pd were characterized by means of perporometry, scanning electron microscopy (SEM), energy dispersive X-ray (EDX). The hollow fibre analyzed shows a five-layer structure with remarkable morphological differences. An estimation of pore diameters and their distribution was performed giving a mean pore diameter of 100 nm. The permeance and selectivity of the fibres were measured using $H_2,\;N_2,\;O_2$ as single gases, at different operating conditions. An $H_2$ permeance of $37 mmol/m^2s$ was measured and $H_2/O_2$ and $H_2/N_2$ selectivities of ca. 3 were obtained. $H_2$ permeance was 1/3 when a water stream flows in the shell side. Catalytic fibrebehaviour was simulated using a mathematical model for a loop membrane reactor, considering only $O_2$ and $H_2$ diffusive transport inside the membrane and their catalytic reaction. Dimensionless parameters such as the Thiele modulus are employed to describe the system behaviour. The model agrees well with the experimental reaction data.

• Journal of the Korean Institute of Landscape Architecture
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• v.35 no.6
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• pp.14-20
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• 2008

The agricultural reservoir watershed plan suggests three specific indices or ways to measure the potential for maintaining reservoir quality in balance with existing or proposed uses: an index of the reservoir's vulnerability to accelerated eutrophication, an index of the degree of land use intensity in reservoir watersheds, and an index of present water quality. Three items that contribute to reservoir eutrophication are included in the vulnerability index: the ratio of reservoir volume to drainage-basin area, shoreline configuration, and mean depth. The watershed land-use intensity index is based on road proximity and upland watershed land-use intensity. Water quality can be given a COD level. All six indicators are considered separately and then rated as follow: low (1), medium (2), or high (3). Five out of 30survey sites were less than 8points, 17sites were less than 11points and 8sites were less than 14points. This study suggests that the sites in the first ranking were potential areas for preservation, sites in the second ranking were potential areas for environmental friendly planning and sites in the third ranking were potential areas for residential need oriented planning. The advantage of this study is the low cost of gathering data for the development of local policy for the planning, management and protection of reservoir basin.