• Journal of The Korean Astronomical Society
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• v.37 no.5
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• pp.307-313
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• 2004

Clusters of galaxies are believed to constitute a population of astrophysical objects potentially able to emit electromagnetic radiation up to gamma-ray energies. Evidence of the existence of non-thermal radiation processes in galaxy clusters is indicated from observations of diffuse radio halos, hard X-ray and EUV excess emission. The presence of cosmic ray acceleration processes and its confinement on cosmological timescales nearly inevitably yields in predicting energetic gamma-ray emission, either directly deduceably from a cluster's multifreqency emission characteristics or indirectly during large-scale cosmological structure formation processes. This theoretical reasoning suggests several scenarios to actually detect galaxy clusters at gamma-ray wavelengths: Either resolved as individual sources of point-like or extended gamma-ray emission, by investigating spatial-statistical correlations with unidentified gamma-ray sources or, if unresolved, through their contribution to the extragalactic diffuse gamma-ray background. In the following I review the situation concerning the proposed relation between galaxy clusters and high-energy gamma-ray observations from an observational point-of-view.

• Management Science and Financial Engineering
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• v.3 no.1
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• pp.39-56
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• 1997

This paper applies the binary tree classifier and discriminant analysis methods to predicting failures of banks and insurance companies. In this study, discriminant analysis is generally better than the binary tree classifier in the classification of bank defaults; the binary tree is generally better than discriminant analysis in the classification of insurance company defaults. This situation can be explained that the performance of a classifier depends on the characteristics of the data. If the data are dispersed appropriately for the classifier, the classifier will show a good performance. Otherwise, it may show a poor performance. The two data sets (bank and insurance) are analyzed to explain the better performance of the binary tree in insurance and the worse performance in bank; the better performance of discriminant analysis in bank and the worse performance in insurance.

• East Asian mathematical journal
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• v.28 no.2
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• pp.173-195
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• 2012

The purpose of this study is to help for an in-depth understanding of their thinking process by observing and analyzing the response found by two elementary school students, Through this study, the following findings could be obtained. First, two students have a tendency trying to solve the complex situation at first. Second, we could know that it is an important factor in discovering the pattern to predict it. Third, we could know that the activity of reconstructing the data meaningfully is an important factor in discovering the pattern. Fourth, it is an important factor in finding the pattern to work organically the activity of predicting it with the activity of reconstructing the data meaningfully. We hope that this study offers the help for an in-depth understanding of students's thinking process.

• Korean Journal of Child Studies
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• v.33 no.6
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• pp.71-84
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• 2012

The purpose of this study is to analyze the relationship between decision making abilities young children and their self-directed learning abilities. A survey was carried out using 160 young children in the J region. The collected data were analyzed by Pearson correlation and multiple regression techniques using the SPSS statistics program. The conclusions are as follows : First, decision making abilities in young children exhibited a positive correlation with their self-directed learning abilities. Second, decision making abilities in young children were an influential variable in terms of their self-directed learning abilities. As a result, decision making abilities in young children were an important variable in predicting their self-directed learning abilities.

• International Journal of Precision Engineering and Manufacturing
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• v.9 no.3
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• pp.40-45
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• 2008

This paper presents a linear positioning system and its control algorithm design with nano accuracy/resolution. The basic linear stage structure is driven by an ultrasonic motor and its displacement feedback is detected by a LDGI (Laser Diffraction Grating Interferometer), which can achieve nanometer resolution. Due to the friction driving property of the ultrasonic motor, the driving situation differs in various ranges along the travel. Experiments have been carried out in order to observe and realize the phenomena of the three main driving modes: AC mode (for mm motion), Gate mode (for ${\mu}m$ motion), and DC mode (for nm motion). A proposed FCMAC (Fuzzy Cerebella Model Articulation Controller) control algorithm is implemented for manipulating and predicting the velocity variation during the motion of each mode respectively. The PCbased integral positioning system is built up with a NI DAQ Device by a BCB (Borland $C^{++}$ Builder) program to accomplish the purpose of an intelligent nanopositioning control.

• Structural Engineering and Mechanics
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• v.58 no.6
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• pp.989-999
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• 2016

Moist curing of concrete is a time consuming procedure. It takes minimum 28 days of curing to obtain the characteristic strength of concrete. However, under certain situations such as shortage of time, weather conditions, on the spot changes in project and speedy construction, waiting for entire curing period becomes unaffordable. This situation demands early strength of concrete which can be met using accelerated curing methods. It becomes necessary to obtain early strength of concrete rather than waiting for entire period of curing which proves to be uneconomical. In India, accelerated curing methods are used to arrive upon the actual strength by resorting to the equations suggested by Bureau of Indian Standards' (BIS). However, it has been observed that the results obtained using above equations are exaggerated. In the present experimental investigations, the results of the accelerated compressive strength of the concrete are used to develop the regression models for predicting the short term and long term compressive strength of concrete. The proposed regression models show better agreement with the actual compressive strength than the existing model suggested by BIS specification.

• International Journal of Advanced Culture Technology
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• v.5 no.3
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• pp.40-45
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• 2017

This data mining technique was used to extract useful information from percutaneous coronary intervention data obtained from the US public data homepage. The experiment was performed by extracting data on the area, frequency of operation, and the number of deaths. It led us to finding of meaningful correlations, patterns, and trends using various algorithms, pattern techniques, and statistical techniques. In this paper, information is obtained through efficient decision tree and cluster analysis in predicting the incidence of percutaneous coronary intervention and mortality. In the cluster analysis, EM algorithm was used to evaluate the suitability of the algorithm for each situation based on performance tests and verification of results. In the cluster analysis, the experimental data were classified using the EM algorithm, and we evaluated which models are more effective in comparing functions. Using data mining technique, it was identified which areas had effective treatment techniques and which areas were vulnerable, and we can predict the frequency and mortality of percutaneous coronary intervention for heart disease.

• Journal of Information Technology Applications and Management
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• v.11 no.3
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• pp.89-116
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• 2004

Insurance companies are in a fierce race to catch a new customer. In this situation. sales force automation technologies are often used to support customer relationship management strategies. This study sets out a research model predicting SFA(Sales Force Automation) usage through theoretical studies. Survey data were collected from 145 salespeople across 2 firms that had implemented sales force automation tools and hypotheses were tested empirically. Data were analyzed by path-analysis method of AMOS. The major findings of this study are as follows: Computer self-efficacy, user involvement and voluntariness have a statistically significant influence on the positive perceptions of SFA. These perceptions have a statistically significant influence on user satisfaction and usage of SFA. while user satisfaction has a statistically significant influence on SFA usage. This paper concludes with the discussion of these results and their implications for academic researchers and insurance company managers.

• International Journal of Human Ecology
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• v.5 no.1
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• pp.35-43
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• 2004

The purposes of this study are to examine effects of household characteristics and risk tolerance attitude on risk tolerance behavior and to investigate the effect of risk tolerance attitude and behavior on financial satisfaction. For this study, data were collected during October of 2001 through a popular Web site for women in South Korea (www.azoomma.com). The participants in this study were 609 housewives, resulting in 607 with usable data. Multiple regression and path analysis were conducted using the SPSS for Windows. Findings suggest that the greater is risk tolerance attitude, the greater is risk tolerance behavior and those who exhibit more risk tolerance behavior tend to be more satisfied with their personal financial situation. It implies that risk tolerance behavior playa positive role in predicting financial satisfaction. The results have implication for family economists and educators in developing educational program and presenting strategic to increases financial well-being, and also for financial counselors and planners in suggesting portfolio advice to their client

• Journal of Aerospace System Engineering
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• v.9 no.4
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• pp.67-72
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• 2015

The analysis has been performed on the blockage effect at the propellant flow passage in a liquid rocket engine. This simulates an example of emergency situation where flow passage is partially blocked. The analysis method has been validated by predicting the pump head and flow rate within 1% precision against the measured data of turbopump-gas generator coupled test. When the oxidizer passage is reduced it is predicted that the mixture ratio decreases, the oxidizer pump head increases and the gas generator pressure increases. When the fuel passage is reduced it is predicted that the mixture ratio increases, fuel flow rate decreases and the fuel pump head increases.