• Proceedings of the Korea Concrete Institute Conference
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• 2001.05a
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• pp.333-338
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• 2001

Fractal geometry is a non-Euclidean geometry which has been developed to quantitative analysis irregular or fractional shapes. Fractal dimension of irregular surface has fractal values ranging from 2 to 3 and of irregular line profile has fractal values ranging from 1 to 2. In this paper, quantitative analysis of crack growth patterns during the fracture processing of fiber-reinforced cement composites based on fractal geometry. The fracture behaviors of fiber reinforced mortar beams subjected to three-point loading in flexure. The beams all had a single notch depth, but varing volume fractions of polypropylene, cellulose fibers. The crack growth behaviors, as observed through the image processing system, and the box counting method was used to determine the fractal dimension, Df. The results showed that the linear correlation exists between fractal dimension and fracture energy of the fiber reinforced cement mortar.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2006.04a
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• pp.431-436
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• 2006

The latest system of GIS has been changing from 2 dimension to 3 dimension. According to the rapid growth of the fields linked to 3D GIS, 3D GIS has variously affected the public field, the national defense field, and the industrial field. This study estimated sight distance safety of curve section considering the environmental impact based on 3D GIS. Sight distance is calculated from the relation between road which keeps the three-dimension character and driver gaze, so it needs to consider both plane and vertical ior the accurate measuring. This study made analysis of the sight distance through considering the environmental impact with driving simulation of design speed 80km/h and running speed 60-120km/h.

• Journal of the Korean Operations Research and Management Science Society
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• v.19 no.2
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• pp.119-128
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• 1994

There are three important regions im Multiple Objective Linear Programming (MOLP). One is the region of efficient solutions, another is the region of weight to be used for finding efficient solutions, the third is the region of efficient (nondominated) objective values. In this paper, first, we find the condition of extreme point in the region of efficient objective values. Second, we find that the sum of the dimension of the weight region and the dimension of efficient objective values region is constant. Using the above, it is shown that we find the shape and dimension of weight region corresponding to the given region or efficient objective values and vice versa.

• International Journal of Contents
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• v.5 no.2
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• pp.1-5
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• 2009

This study was to analyze important dimensions and its factors of micro level of e-learning determining the quality of e-learning. E-learning dimensions and their factors were identified and developed from the analytical review of related researches. From literature review and survey as well as expert interview, six categories of e-learning identified from this study were: 1) curriculum content, 2) usability, 3) instructional design, 4) evaluation -both process and results, 5) management, and 6) refinement and improvement. A total of thirty-seven factors determining the quality of the e-learning six categories were identified. The rank order and contribution rates for each categories and factors were calculated to explain how importantly they contribute to the quality of e-learning. Also three dimensions such as controlling the e-learning quality, e-learning fundamental dimension e-learning process dimension, and e-learning product dimension, were explained. This study suggests a useful guidance for e-learning quality and evaluation framework for better results.

• The Journal of Information Technology and Database
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• v.8 no.2
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• pp.61-69
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• 2001

System Integration Projects, especially in public sector, have a tendency of growing in size and duration. Under such environment the effects of IT personnel turnover becomes a serious problem. In addition a high rate of turnover hinders shill accumulation and competitiveness obtainment. In this research we explored the reasons of turnover by way of tracing IT personnel who have involved in large-scale SI projects and moved or quit before the completion of the projects. Based on previous research we identified three dimensions of variables that affected turnover : task-related dimension, human relations dimension, treatment-related dimension. We used these dimensions as a guideline for the interview and questioning exploration. Implications from the research for improving IT Personnel management are also elaborated.

• Journal of Korean Public Health Nursing
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• v.31 no.1
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• pp.121-134
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• 2017

Purpose: The goal of this study was to define and clarify the concept of "self management" of children with chronic diseases. Methods: For analyzing the concept of self management, this study used the hybrid model. This study involved in-depth interviewing nine children with chronic disease. Results: The concept of self management of children with chronic disease can be categorized with three dimensions: internal, environmental, and behavioral aspects. Besides, five attributes and thirteen indicators were analyzed. The concept of self management of children with chronic disease can be expressed as a kind of process; a) re-established yourself (internal dimension), b) assistance by the surrounded (environmental dimension), and c) positive health management behavior with self control of daily life (behavioral dimension). Conclusion: The self management is important for children with chronic disease to control their disease for long time. The attributes and indicators drawn by this study could be used for tool development and useful resources of self management competence in children with chronic disease.

• Journal of the korean society of oceanography
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• v.35 no.1
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• pp.11-15
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• 2000

The scaling behavior of random fractals and multifractals is investigated numerically on the seabottom depth in the seabottom topography. In the self-affine structure the critical length for the crossover can be found from the value of standard deviations for the seabottom depth. The generalized dimension and the spectrum in the multifractal structure are discussed numerically, as it is assumed that the seabottom depth is located on a two-dimensional square lattice. For this case, the fractal dimension D$_0$ is respectively calculated as 1.312476, 1.366726, and 1.372243 in our three regions, and our result is compared with other numerical calculations.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.211-211
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• 2000

The multiple targets tracking problem has been one of main issues in the radar applications area in the last decade. Besides the standard Kalman filtering, various methods including the variable dimension filter, input estimation filter, interacting multiple model (IMM) filter, federated variable dimension filter with input estimation, probable data association (PDA) filter etc. have been proposed to address the tracking and sensor fusion issues. In this paper, two existing tracking algorithms, i.e. the IMMPDA filter and the variable dimension filter with input estimation (VDIE), are combined for the purpose of improving the tracking performance of maneuvering targets in clutter. To evaluate the tracking performance of the proposed algorithm, three typical maneuvering patterns i.e. Waver, Pop-Up, and High-Diver motions, are defined and are applied to the modified IMMPDA filter considered as well as the standard IMM filter. The smaller RMS tracking errors, in position and velocity, of the modified IMMPDA filter than the standard IMM filter are demonstrated through computer simulations.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2007.04a
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• pp.135-140
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• 2007

In this paper, an Improved Dimension Reduction(IDR) method is proposed for uncertainty quantification that employes Kriging interpolation technic. It has been acknowledged that the DR method is accurate and efficient for assessing statistical moments and reliability due to the sensitivity free feature. However, the DR method has a number of drawbacks such as instability and inaccuracy for problems with increased nonlineality. In this paper, improved DR is implanted by three steps. First, the Kriging interpolation method is used to accurately approximate the responses. Second, 2N+1 and 4N+1 ADOEs are proposed to maintain high accuracy of the method for UQ analysis. Third, numerical integration scheme is used with accurate but free response values at any set of integration points of the surrogated model.

• Journal of Community Nutrition
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• v.8 no.3
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• pp.153-159
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• 2006

The current exploratory study investigates and compares the perceptions of the service quality of in-flight meals through the evaluation of recent consumers (within 2 weeks) of services provided by Korean and foreign-based airlines. Twenty (20) items for measuring service quality were categorized into three factor dimensions of 'food quality', 'employee service', and 'professionalism'. Among these, 'employee service' was rated highest by Korean and foreign-based airlines. When items representing each service quality dimension were analyzed and compared, only the 'food quality' dimension of Korean-based airlines was perceived higher than that of other foreign-based airlines. Findings also revealed a spectrum with some items with higher or lower mean values within each service quality dimension. Results of this study can expectedly be used to benefit both from a theoretical and practical point of view by providing empirical data that measure the service quality of in-flight meal service.