• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.19 no.9
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• pp.1028-1036
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• 2008

In the OFDM system, IQ imbalance problem happens at the RF front-end of transceiver, which degrades the BER(bit error rate) performance because it affects the constellation in the received signal. Also, phase noise is generated in the local oscillator of transceivers and it destroys the orthogonality between the subcarriers. Conventional PNS algorithm is effective for phase noise suppression, but it is not useful anymore when there are jointly IQ(In-phase and Quadrature) imbalance and phase noise. Therefore, in this paper, we analyze the effect of IQ imbalance and phase noise generated in the down-conversion of the receiver. Then, we estimate and compensate the IQ imbalance and phase noise at the same time. Compared with the conventional method that IQ imbalance after IFFT is estimated and compensated in front of FFT via the feedback, this proposed method extracts and compensates effect of IQ imbalance after FFT stage. In case IQ imbalance and phase noise exist at the same time, we can decrease complexity because it is needless to use elimination of IQ imbalance in time domain and training sequences and preambles. Also, this method shows that it reduces the ICI and CPE component using adaptive forgetting factor of MMSE after FFT.

• Korean Journal of Health Education and Promotion
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• v.20 no.2
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• pp.95-112
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• 2003

Objectives： Oral health care program for the elementary school children (ESOHCP) should be met the first priority because dental caries are highly sensitive and prevalent among them. This study was performed to enhance the efficiency of ESOHCP, and their oral health promotion. Methods： The Subjects were 346 students (3rd grade 163, 6th grade 185) of one elementary school in Busan. Dental IQ and actual oral health status； the decayed, mixing and filling teeth were checked through questionnaire and oral health examination from April to June 2002. Dental IQ was presented out of one hundred, and data analysis was done using SAS (ver 8.1) program. Results： The students' cognitive level about the causative and preventive factor of dental caries was relatively high. However, the practical aspects of preventive behavior - tooth brushing； three times per day (20％), three minutes per time (22％), oral health examination； one time per three months (10％) left much to be desired. And, only 27％ of the subjects had experienced in school oral health education. The mean level of dental IQ was 79 out of 100, and 51 ％ and 42％ of them had the decayed and teeth with filling, respectively, with the rate of DMFT 82％, DT 43％, FT 57％. The level of dental IQ was higher in case of having his (her) own tooth brush (p＝0.072), standard tooth brushing (p<0.001) three times per day, post meal, three minutes per time, present experience of oral health examination (p<0.001) and dental clinic visit (p<0.001). The grade of caries was more serious in case of 6th grade (p＝0.059), an absence of his (her) own tooth brush (p＝ 0.090), present experience of oral health examination (p＝0.021), and an absence of regular dental clinic visit (p＝0.003). The frequency of oral health examination (γ＝ 0.620), tooth brushing； times per day (γ＝0.445), post meal (γ＝0.355), expending times per brushing (γ＝0.352), right cognition to the treatment of caries (γ＝0.401), positive attitude to dental treatment (γ＝0.387), the frequency of dental clinic visit for the past one year (γ＝0.152) showed significant correlation with dental IQ. In the multivariate analysis, dental IQ was influenced by the frequency of oral health examination, right cognition to the cause of caries, times of teeth brushing per day, right cognition to the treatment of caries, etc., with adjusted R2＝0.857. Conclusion： Though the students' cognitive level about the causative and preventive factor of dental caries was high, the practical aspects of preventive behavior left much to be desired. Ant the current ESOHCP considered to be still inefficient. However, frequent dental visits had apparent correlation with hish level of dental IQ. The specialized and practical program should be needed for the efficient ESOHCP. Harmonized effort from educational, health and dental society is essential.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.18 no.7
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• pp.757-765
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• 2007

OFDM system is an excellent high speed transmission method but it is seriously sensitive to the phase noise and IQ imbalance. Therefore, in this paper, we analyze the communication performance of the OFDM communication system with IQ imbalance and phase noise. Phase noise's variance can be calculated by integral calculus of phase noise power spectrum. From simulation results, it can be shown that the BER performances show different change according to the phase noise variance and IQ imbalance amount. When amplitude imbalance is ${\varepsilon}$=0.2; 0.3; 0.4 and phase imbalance is ${\phi}=10^0$, and distribution of phase noise is ${\sigma}^2=0.012$, BER is degraded by 2.88 dB, 3.61 dB, 4.09 dB in $10^{-5}$ in the respect of the SNR penalty.

• Journal of Gifted/Talented Education
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• v.23 no.3
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• pp.421-434
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• 2013

The brains of adolescents experience rapid changes, which has been studied to prove relatedness between neuroanatomical properties and IQ. But, most previous studies infer the relatedness from purely cross-sectional data. This study not only measured the thickness of the cerebral cortex once, but traced its variability and the relatedness between IQ and this variability, which was presumed to be 75. Healthy adolescents (M=16yr. and 4month) were divided into 5-stage categories based on their intellectual ability and MRI scan was made twice every 6 months to measure the variablity of their cerebral cortex. As a result, a big difference in the variability of the cerebral cortex was shown based on their IQ. Three groups with an IQ of more than 120 showed a decrease in the thickness of the cerebral cortex in 11 brain regions, while two groups with an IQ lower than 120 showed an increase in the cerebral cortex thickness in 5 to 8 regions. It is presumed that the lower the IQ, the slower the maturation of the cerebral cortex.

• Journal of Oriental Neuropsychiatry
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• v.20 no.3
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• pp.89-119
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• 2009

Objectives : This study was to investigate the association of Pittsburgh Sleep Quality Index(PSQI), Insomnia Questionaire(IQ), Beck Depression Inventory(BDI) and Diagnos system of oriental medicine(DSOM) in the Insomnia Patients. Methods : For this study, we carried out PSQI, IQ, BDI and DSOM of 37 patients with insomnia who have come to Donguei oriental hospital of Donguei university from November 2008 to May 2009. And Using cross tabulation analysis, verified the association of PSQI, IQ, BDI and DSOM. Results : 1. The most Frequent Pathogenic Factor is blood-deficiency(血虛) in total patients. 2. The score of BDI has positive correlation with sc10 of deficiency of qi(氣虛), damp(濕), kdney(腎) in total patients. 3. The score of PSQI has positive correlation with zp of liver(肝) in total patients. 4. The score of PSQI has positive correlation with sc10 and zp of insufficiency of Yin(陰虛), and the score of BDI has positive correlation with sc10 of blood stasis(血瘀) and zp of liver(肝) in female patients. 5. The score of PSQI has positive correlation with sc10 of deficiency of qi(氣虛) and zp of heart(心), and the score of IQ has positive correlation with sc10 of liver(肝) in male patients. 6. The duration from onset in the group of 22-59years are longer than the group of 60-80 years and the duration of using hypnotics have positive correlation with total sleep time in 22-59years group. 7. The score of PSQI has positive correlation with zp of liver(肝) in 22-59years group. 8. The score of PSQI has positive correlation with the score of BDI in 60-80years group. 9. The score of BDI has positive correlation with sc10 of deficiency of qi(氣虛) and zp of blood-deficiency(血虛), and the score of IQ has positive correlation with zp of coldness(寒) in 60-80years group. 10. The score of IQ has positive correlation with sc10 and zp of dryness(燥) in below 6 Months Group. 11. The score of PSQI has positive correlation with the score of BDI in over 6 Months Group. 12. The score of PSQI has positive correlation with zp of liver(肝) in over 6 Months Group. 13. The score of IQ has positive correlation with sc10 of dryness(燥) in BDI 2nd Grade Group. 14. The score of BDI has positive correlation with sc10 of kidney(腎) and the age has positive correlation with zp of heart(心) in BDI 3rd Grade Group. 15. The age has positive correlation with sc10 of damp(濕) in BDI 4th Grade Group. Conclusions : This study provides insights into the complicated associations of the pattern of insomnia with depression and Diagnos system of oriental medicine. And especially this study showed apparent correlation between insomnia and depression in 60-80years group and over 6 months group.

• Applied Microscopy
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• v.47 no.1
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• pp.43-49
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• 2017

A new method was introduced to distinguish the ferrite, bainite and martensite in transformation induced plasticity (TRIP) steel by using electron backscatter diffraction (EBSD) and transmission electron microscopy (TEM). EBSD is a very powerful microstructure analysis technique at the length scales ranging from tens of nanometers to millimeters. However, iron BCC phases such as ferrite, bainite and martensite cannot be easily distinguished by EBSD due to their similar surface morphology and crystallographic structure. Among the various EBSD-based methodology, image quality (IQ) values, which present the perfection of a crystal lattice, was used to distinguish the iron BCC phases. IQ values are very useful tools to discern the iron BCC phases because of their different density of crystal defect and lattice distortion. However, there are still remaining problems that make the separation of bainite and martensite difficult. For instance, these phases have very similar IQ values in many cases, especially in deformed region; therefore, even though the IQ value was used, it has been difficult to distinguish the bainite and martensite. For more precise separation of bainite and martensite, IQ threshold values were determined by a correlative TEM analysis. By determining the threshold values, iron BCC phases were successfully separated.

• Korean Journal of Child Studies
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• v.30 no.1
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• pp.27-41
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• 2009

This study examined the cognitive and social development of children of low income, disabled mothers. Sixty-four disabled mothers and their 3- to 5-year-old normally developing children participated. Children's IQ, receptive vocabulary, and social adaptive ability were measured with Korean-Wechsler Preschool and Primary Scale of Intelligence (Park et al.,1996), Peabody Picture Vocabulary Test-Revised (Seoul Community Rehabilitation Center, 1995), and Social Maturity Test(Kim & Kim, 1995), respectively. Results showed that IQ and receptive vocabulary scores were lower than average and that verbal IQ was positively related to shared reading time and library use; verbal IQ was negatively related to duration of child-care attendance. Children's social quotient was higher than average and positively related to mother's employment status and amount of books in the home.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.12
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• pp.9-17
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• 2021

Globalization is an economic process responsible for the increase of interdependence of world economies. It enhances the mobility of national resources internationally via the integration of markets, trade and investments with minimal barriers to slow the flow of products and services. Although globalization has some positive impacts on the economy, it is said to be a factor in the decline of income inequality of the participating countries. However, the results of previous studies on the relationship between globalization and income inequality are inconclusive. This suggests that there are other factors influencing the relationship between the two variables. The purpose of this study is to examine the role of intelligence (IQ) in the globalization-income inequality relationship. This study employs the threshold regression technique and cross-nation observations from 117 sample nations for the period 1980-2016. The results show that the impact of globalization on income inequality in a nation relies on its IQ level. The results imply that economic globalization has a negative impact on income inequality in nations with lower IQ levels. It widens the gap between the poor and rich. While in nations with higher IQ levels, it seems to not have any significant impact on income distribution.

• Korean Journal of Child Studies
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• v.30 no.4
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• pp.47-56
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• 2009

This longitudinal study examined picture book reading practices with very young children and its influence on early intellectual development. The home picture book reading activities of 322 infants and their mothers were assessed by questionnaire every 6 months from 18 months till 42 months of age. Infants' IQ was measured with Korean-Wechsler Preschool and Primary Scale of Intelligence(Park et al., 1996) at 42 months. Results showed that monthly book expense (r=.28, p<.01) and infants' asking for reading (r=.14, p<.05) at 18 months were positively correlated with IQ at 42 months. Reading time between 24 and 42 months correlated positively with IQ(r=.17~.34, p<.01). These results reveal the importance of early book environment and actual reading time in the intellectual development of very young children.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.1671-1672
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• 2008

전동기는 일반적으로 우리 일상에서 가장 많이 쓰이는 동력장치 중 하나이다. 이런 전동기를 제어함에 있어서 주기적 외란은 전체 시스템의 안정성에 큰 영향을 미친다. 특히, 정밀제어시스템에서는 반드시 고려되어야 할 요소이다. 본 논문에서는 신호처리기법의 일종인 IQ 변조 알고리즘을 이용한 제어기를 제안한다. 제안하는 제어알고리즘은 외란을 고려하지 않은 시스템모델에 대하여 설계되어진 제어기와 IQ 변조기법을 이용하여 외란을 추정하여 설계되어지는 제어기로 이루어진다. 이 제어 알고리즘은 전동기에서 발생하는 주기적 외란에 의한 오차를 현저하게 줄인다. 본 논문을 통해 제안하는 제어알고리즘의 우수성과 타당성을 검증한다.