• ETRI Journal
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• v.30 no.6
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• pp.765-773
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• 2008

Spatial correlation is a result of insufficient antenna spacing among multiple antenna elements, while temporal correlation is caused by Doppler spread. This paper compares the effect of spatial and temporal correlation in order to investigate the performance of multiuser scheduling algorithms in multiple-input multiple-output (MIMO) broadcast channels. This comparison includes the effect on the ergodic capacity, on fairness among users, and on the sum-rate capacity of a multiuser scheduling algorithm utilizing statistical channel state information in spatio-temporally correlated MIMO broadcast channels. Numerical results demonstrate that temporal correlation is more meaningful than spatial correlation in view of the multiuser scheduling algorithm in MIMO broadcast channels. Indeed, the multiuser scheduling algorithm can reduce the effect of the Doppler spread if it exploits the information of temporal correlation appropriately. However, the effect of spatial correlation can be minimized if the antenna spacing is sufficient in rich scattering MIMO channels regardless of the multiuser scheduling algorithm used.

• Korean Journal of Human Ecology
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• v.9 no.1
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• pp.15-24
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• 2006

The early childhood is a pivotal period for the development of creativity since creative imaginary is rich at the age from 4 to 4.5 years old, The purpose of this study is to examine the relationships between children's creativity, playfulness and multiple intelligence. 91 children(41 boy, 50 girls) attending preschool in jeon-ju city were participated in this research, The age of children was 6 years(average 73.7 months), After collecting the data to find the connections between children's creativity, playfulness and multiple intelligence from the subjects' data using the SPSS WIN 10.0 program, along with t-test, ANOVA and Pearson's correlation in this paper. 1. There was significant correlation between children's playfulness and creativity. Intelligence spontaneousness the element of the playfulness has a correlation with Creativity strengths, Elaboration. In addition, Resistance to Premature Closure has a correlation with social spontaneity, And Originality has a correlation with the Expression of Pleasure the element of the playfulness, 2. There was a significant positive correlation between children's multiple intelligence(MI) and creativity, Fluency the element of creativity has a correlation with Interpersonal intelligence the element of multiple intelligence: And Originality has a correlation with Bodily-kinesthetic intelligence, Intrapersonal intelligence the element of MI. In addition, Abstraction of Titles has a correlation with Intrapersonal intelligence. 3. There was a little correlation between children's MI and playfulness. The Expression of Pleasure has a correlation with bodily-kinesthetic intelligence, Based on the current study, the relationships between creativity, playfulness, and multiple intelligence could be identified. Especially, creativity was significantly correlated with playfulness and multiple intelligence of early childhood. Therefore, it was found that creativity of toddler might be essential factor for the development of toddler's cognitivity.

• Journal of applied mathematics & informatics
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• v.19 no.1_2
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• pp.521-525
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• 2005

Case deletion diagnostic for multiple correlation coefficient is considered. A method of detecting observations that can hide or create multicollinearity is suggested. A numerical example is given for illustration.

• Journal of the Korean Statistical Society
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• v.31 no.2
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• pp.163-175
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• 2002

An extended version of the minimax eccentricity factor estimation for multiple set case is proposed. In addition, two more simple methods for multiple set factor analysis exploiting the concept of generalized canonical correlation analysis is suggested. Finally, a certain connection between the generalized canonical correlation analysis and the multiple set factor analysis is derived which helps us clarify the relationship.

• Journal of the East Asian Society of Dietary Life
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• v.16 no.2
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• pp.128-135
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• 2006

This study was conducted to determine the relationship between intake of food unconformable to each Sasang constitution and the recognition of irregular symptoms of health condition. The study subjects, 362 university students nationwide, were classified according to their Sasang constitution. Regarding the correlation between intake of constitutionally unconformable food and health recognition, the Soeum type showed a positive correlation between unconformable food intake and multiple subjective symptoms. According to the detailed food type, the Soyang type showed a positive correlation between chicken intake and the symptoms of eyes and skin, and between pepper intake and multiple subjective symptoms. The Soeum type showed a negative correlation between mackerel intake and the symptoms of mouth and anus. A negative correlation was observed between mung-bean intake and multiple subjective symptoms, and this tendency persisted in the correlations between nonglutinous millet intake and multiple subjective symptoms, between wheat powder intake and multiple subjective symptoms, and not only the symptoms of the respiratory system but also eyes and skin. Positive correlations were found between banana intake and multiple subjective symptoms, and between mile intake and the symptoms of the respiratory system. However, the Taeum type didn't display any significant correlation with any food type.

• Journal of the Korean Society for Precision Engineering
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• v.11 no.1
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• pp.166-176
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• 1994

The problem of reducing the vibration level of elastic plates driven by multiple random point forces is analyzed in this study. First, the analytical solution for the vibration level of finite thin plates with four simply supported edges under the action of multiple random point force is derived. By assuming the plates to be lightly damped, an approximate solution for the vibration level of the plate is obtained. A numerical study is carried out to determine an optimal spacing distance between the multiple point forces in order to produce a relative minimum in the plate's vibration level. The optimal spacing distance is shown to depend on the given excitation band. The effects of wave cancellation in the near field of the multiple point forces are discussed by using the equivalence of certain stationary random responses and deterministic pulse responese.

• Journal of Institute of Control, Robotics and Systems
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• v.12 no.10
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• pp.1050-1055
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• 2006

Since the muiltipath signal arrives at the GPS receiver later than the line-of-sight signal, the multipath signal makes the shape of the correlation function asymmetric. This paper proposes a multipath mitigation method through asymmetry estimation of the correlation function, in which multiple correlators are utilized. The asymmetry is estimated from correlation values of correlators which have different chip spacings. Based on the estimated asymmetry, the correlation function is modified in order to get a better code tracking performance. Even through the proposed method uses multiple correlators including the narrow correlator, the acquisition performance is not degraded since the number of search cell of the narrow correlator part can be reduced in the algorithm of the proposed method. The simulation results show that the proposed method gives better performance than the generic correlator in multipath environment.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.5
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• pp.2559-2564
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• 2016

Purpose: To compare Ki-67 index and microvessel density MVD) in multiple myeloma and non-myeloma patients and their correlation with each other and other prognostic markers. Materials and Methods: Forty patients were enrolled in this study between 2011-2013, 30 with multiple myelomas and 10 with non-malignant disease as controls. Proliferative activity was analyzed by Ki-67 and microvessel density (MVC) was assessed by CD34 and compared between two groups. In myeloma patients, correlation between Ki-67, MVD and other prognostic factors was assessed by Pearson correlation coefficient. Results: According to Durie Salmon staging criteria, 13 patients were of stage 1, 5 of stage II and 12 of stage III. Ki-67 expression showed a positive correlation with MVD (r=0.729, p<0.001) and was significantly higher (p<0.0001) in myeloma patients (range 35-80%, mean 60.1 %) as compared to controls (range 8-25%, mean 18.1%). $MVD/mm^2$ was also significantly (p<0.0001) higher in myeloma patients (range $62-237/mm^2$, mean $178.0/mm^2$) than controls (range $5.2-50/mm^2$, mean $18.3/mm^2$). Ki-67 and MVD, both increased progressively with increasing stage of myeloma. Ki-67 showed significant positive correlation with blood urea and lactate dehydrogenase and a significant negative correlation with serum albumin. MVD showed a significant positive correlation with blood urea, lactate dehydrogenase, serum creatinine, ${\beta}2$ microglobulin and skeletal lesions. Conclusions: Ki-67 and MVD are indicators of aggressiveness and poor prognosis having significant correlation with each other and other prognostic markers of multiple myeloma. Routine assessment of these markers may help to identify high risk patients, who may benefit from with more aggressive therapy.

• Journal of Korean Home Economics Education Association
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• v.14 no.3
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• pp.51-64
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• 2002

The Purposes of This Study is to investigate the relationships among Multiple Intelligence(MI). Creativity and Home Economics achievements of the middle & high school students. The research of this study are performed as follows Subject of this study were 142 middle school student & 127 girls' high school. And The “Creativity Test” developed by Korean Creativity Research Institute(1998). Multiple Developmental Assesment scale were administrated as data gathering tools And end-term exam scores on 9 subject were collected as the measure of academic achievement. Especially the Home Economics achievement were collected with Written test and performance assesment. The data were analysed by pearson's correlation. The findings of this study were as follows: 1) A statistically significant correlation among the MI and Home Economics achievements in middle school students(linguistic, Logical-mathematical. Musical. Interpersonal, Intrapersonal) and high school students(linguistic, Logical-mathematical, Interpersonal) were found. But There were not statistical difference between another 8 subjects. 2) In middle school students. a statistically significant correlation among the creativity and Home Economics achievements were found But in high school students, statistically significant correlation among the creativity and Home Economics achievements were not found 3) In MI and Home Economics achievements correlation. there were not difference between written test and performance assesment.

• ETRI Journal
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• v.45 no.5
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• pp.768-780
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• 2023

The application of unmanned aerial vehicles (UAVs) has recently attracted considerable interest in various areas. A three-dimensional multiple-input multiple-output concentric two-hemisphere model is proposed to characterize the scattering environment around a vehicle in an urban UAV-to-vehicle communication scenario. Multipath components of the model consisted of lineof-sight and single-bounced components. This study focused on the key parameters that determine the scatterer distribution. A time-variant process was used to analyze the nonstationarity of the proposed model. Vital statistical properties, such as the space-time-frequency correlation function, Doppler power spectral density, level-crossing rate, average fade duration, and channel capacity, were derived and analyzed. The results indicated that with an increase in the maximum scatter radius, the time correlation and level-crossing rate decreased, the frequency correlation function had a faster downward trend, and average fade duration increased. In addition, with the increase of concentration parameter, the time correlation, space correlation, and level-crossing rate increased, average fade duration decreased, and Doppler power spectral density became flatter. The proposed model was compared with current geometry-based stochastic models (GBSMs) and showed good consistency. In addition, we verified the nonstationarity in the temporal and spatial domains of the proposed model. These conclusions can be used as references in the design of more reasonable communication systems.