• Geophysics and Geophysical Exploration
• /
• v.2 no.2
• /
• pp.86-95
• /
• 1999

This paper presents an efficient three-dimensional (3-D) modeling algorithm using the extended approximation to an electric field integral equation. Numerical evaluations of Green's tensor integral are performed in the spatial wavenumber domain. This approach makes it possible to reduce computing time, to handle smoothly varying conductivity model and to remove singularity problems encountered in the integration of Green's tensor at a source point. The responses obtained by 3-D modeling algorithm developed in this study are compared with those by the full integral equation for a thin-sheet EM scattering. The extensive analyses on the performance of modeling algorithm are made with the conductivity contrasts and source frequencies. These results show that the modeling algorithm are accurate up to the conductivity contrast of 1:16 and the frequency range of 100 Hz-100 kHz. The extended Born approximation, however, may produce inaccurate results for some source and model configurations in which the electric field is discontinuous across the conductivity boundary. We performed the modeling of a composite model of which conductivity varies continuously and this shows the modeling algorithm developed in this study is efficient for 3-D EM modeling. For a cross-hole source-receiver configuration a composite model of which conductivity varies continuously can be successfully simulated using this algorithm.

• Clinical and Experimental Pediatrics
• /
• v.59 no.10
• /
• pp.414-420
• /
• 2016

Purpose: We investigated behavioral problems, attention problems, and cognitive function in children and adolescents born small for gestational age (SGA). Methods: Forty-six SGA children born at term and 46 appropriate for gestational age (AGA) children born at term were compared. Psychiatric symptoms were examined with reference to the Korean-Child Behavior Checklist, Korean-Youth Self Report, and Attention Deficit Hyperactivity Disorder Rating Scale (ADHD-RS). Cognitive function was estimated using the Wechsler Intelligence Scale. Sociodemographic data were recorded from interviews. Results: SGA children had high scores on delinquent behavior, aggressive behavior, and the externalizing scale, and they also showed a propensity for anxiety and depression. The SGA group had a higher mean ADHD-RS score than the AGA group ($10.52{\pm}8.10$ vs.$9.93{\pm}7.23$), but the difference was not significant. The SGA group had a significantly lower verbal intelligence quotient (IQ) than the AGA group, but the mean scores of both groups were within normal limits. Conclusion: This study indicates marked behavioral problems, such as delinquency, aggressiveness, and anxiety and depression, as well as low verbal IQ in the SGA group than in the AGA group. Even in cases in which these symptoms are not severe, early detection and proper treatment can help these children adapt to society.

• Child Health Nursing Research
• /
• v.25 no.4
• /
• pp.468-476
• /
• 2019

Purpose: This study was conducted to evaluate cognitive ability in preschoolers born prematurely and to investigate related factors. Methods: A prospective, longitudinal study was conducted with 64 children at 5-6 years of corrected age (CA) (second follow-up) among 76 children who had been assessed at 2.0~3.5 years of CA (first follow-up) from a sample of 343 preterm infants born from 2008 to 2010. To evaluate each child's cognitive ability, during a home visit, we used the Kaufman Assessment Battery for Children-II (KABC-II) at the second follow-up. To explore factors related to cognitive ability, we measured children's hemoglobin level at the second follow-up and used the data collected in our previous study, including the Bayley Scale of Infant Development-II (BSID-II) at the first follow-up. Results: The mean total KABC-II quotient was $117.0{\pm}14.4$. The 5-minute Apgar score (${\beta}=.29$, p=.006), hemoglobin level (${\beta}=.22$, p=.032), and the mental development index quotient of the BSID-II (${\beta}=.51$, p<.001) were statistically significant predictors of the KABC-II quotient in multiple linear regression analysis. Conclusion: The cognitive function of young children born prematurely was influenced by early neurodevelopment and factors reflecting their health status, such as anemia and a low 5-minute Apgar score.

• Journal of Korea Trade
• /
• v.27 no.1
• /
• pp.159-175
• /
• 2023

Purpose - This paper empirically investigates the relationship between born global strategy and the accounting- and market- based financial performance of Korean firms. Further, this study identifies the characteristics of born global firms (BGs) in comparison with non-BG counterparts in terms of size, R&D, and liability. Design/methodology - Using a database of listed Korean SMEs in the manufacturing sector from 2010 to 2020, this study applies panel generalized least squares (GLS) estimation and logistic regression techniques. Findings - This study finds that BG strategy is negatively related to the firm's accounting-based financial performance, while it is positively related to the market-based financial performance. This study also finds that BGs have higher sales volume and more total assets compared to their non-BG counterparts. In addition, Korean BGs spend more on R&D, and at the same time have higher liability. Originality/value - BGs, by definition, are firms that are actively penetrating foreign markets from the early stages of their establishment. Previous studies of Korean BGs have tried to identify the determinants of BGs' rapid internationalization and their superior performance. However, most of these studies have utilized either qualitative case- or survey-based analyses with relatively limited numbers of observations. From a different perspective, this study provides more objective evidence by investigating how the BG strategy affects the financial and market performance of firms, and by characterizing BGs in terms of financial data.

• Journal of the Korean Chemical Society
• /
• v.28 no.3
• /
• pp.170-175
• /
• 1984

The transport rates of $H^+$ ion by DBC and DCC as carrier molecules through organic liquid membranes were determined at 25$^{\circ}$C. The transport rates depend highly on the dielectric constants of membrane solvents and these results were discussed in terms of Born's potential energy barrier methods. The sizes of anions also affect the transport rates and these results were well explained theoreticlly by extended Born's equation.

• Child Health Nursing Research
• /
• v.24 no.2
• /
• pp.220-228
• /
• 2018

Purpose: This study was conducted to measure adiposity and to investigate related factors in preschoolers born prematurely. Methods: A longitudinal follow-up study was conducted with 52 preschoolers at 5 years of corrected age among 343 preterm infants. Their adiposity status was evaluated based on measurements of body mass index, subscapular and triceps skin fold thickness (SFT), waist circumference, waist-to-height ratio, and mid-arm circumference at a home visit. Results: The findings showed that SFT measurements, particularly at the triceps, reflected the degree of adiposity more accurately than other conventional measures. A shorter gestation, older maternal age, and the mother having more years of formal education were associated with higher levels of adiposity in the preschoolers. Conclusion: The adiposity of children born prematurely needs to be thoroughly monitored with additional SFT measurements, considering the risk of accelerated growth patterns overriding regular catch-up growth in children born prematurely.

• Clinical and Experimental Pediatrics
• /
• v.57 no.9
• /
• pp.379-383
• /
• 2014

Recombinant growth hormone (GH) is an effective treatment for short children who are born small for gestational age (SGA). Short children born SGA who fail to demonstrate catch-up growth by 2-4 years of age are candidates for GH treatment initiated to achieve catch-up growth to a normal height in early childhood, maintain a normal height gain throughout childhood, and achieve an adult height within the normal target range. GH treatment at a dose of $35-70{\mu}g/kg/day$ should be considered for those with very marked growth retardation, as these patients require rapid catch-up growth. Factors associated with response to GH treatment during the initial 2-3 years of therapy include age and height standard deviation scores at the start of therapy, midparental height, and GH dose. Adverse events due to GH treatment are no more common in the SGA population than in other conditions treated with GH. Early surveillance in growth clinics is strongly recommended for children born SGA who have not caught up. Although high dose of up to 0.067 mg/kg/day are relatively safe for short children with growth failure, clinicians need to remain aware of long-term mortality and morbidity after GH treatment.

• Korean Journal of Applied Biomechanics
• /
• v.18 no.2
• /
• pp.125-139
• /
• 2008

The purpose of this study is to compare and analyze a kinematic characteristics of throwing performance among born visually impaired, postnatal visually impaired and visually correct people through their kinematic characteristics. Another purpose of this study is to prevent injury and improve blind's exercise leadership and physical abilities. Three video cameras were used and each camera's shooting velocity was 60field/sec. Then the longest thrown pose was collected and analyzed by using Kwon 3D ver. 3.1 program. The results obtained from this study were followings; 1. During release, the fastest speed of ball was visually corrected followed by postnatal visually impaired and then born visually impaired. 2. Visually corrected used wrist joint well and had wide body round range with similar motion patterns, however born visually impaired couldn't do this at all. 3. Visually corrected used waist to lead shoulder at Phase 2 while throwing ball, but some of born visually impaired and postnatal visually impaired couldn't use waist to lead shoulder. 4. Visually corrected looked at the way where ball would go, but blinds couldn't look where ball would go. 5. Not like visually corrected who show similar patterns, born visually impaired showed each different patterns and some postnatal visually impaired showed similar patterns with visually corrected. 6. While throwing ball, visually corrected showed flexible weight-movement, postnatal visually impaired were not good as visually corrected, and born visually impaired couldn't do weight-movement at all. Synthetically, this result showed that throwing motions are affected a lot by the time when people became blind.

• Journal of Oriental Neuropsychiatry
• /
• v.23 no.4
• /
• pp.123-132
• /
• 2012

Objectives : This study aims to investigate the correlation between the characteristics of personality on MMPI scale, and the siblings relation, number of current family living with, gender and age of the Oriental Medical University students. Methods : For this study, we carried out the MMPI profiling and gathered information regarding the sibling relation of the subjects. We studied the correlation between the two measures, and the correlation between MMPI scales and the subjects' gender and age. Results : 1. The group without siblings had higher STY figures then the groups with siblings. 2. There was no significant differences in MMPI profiles among the only child group, first-born group, second-born group, and third-born group. 3. The married group showed higher Pd, Pt, Sc, BDL figures than the unmarried group. 4. As the number of family members currently living with increased, the BDL and STY figures decreased. 5. The male group had higher Hs, Hy, Pa, Ma, NAR, BDL, ANT, CPS, PAR, and SZD figures, while the female group had higher D, Pd, Mf, Pt, HST, PAG, and DEP figures. 6. As the subjects' age increased, the figure of Hs, D, Pt, Sc, Si, AVD, and SZD increased, while the HST figure decreased. Conclusions : By the above results, we can assume that the sibling relations and the order one is born in the family does not affect one's personality much in grown-ups; whereas the gender and age affect the personality.

• Journal of the Korean Geophysical Society
• /
• v.5 no.1
• /
• pp.63-71
• /
• 2002

The integral equation method is a powerful tool for electromagnetic numerical modeling. But the difficulty of this technique is the size of their linear equations, which demands excessive memory and calculation time to invert. This limitation of the integral equation method becomes critical in inverse problem. To overcome this limitation, a lot of approximation and series methods, such as conventional Born, modifed Born and extended Born, were developed. But all the methods need volume integration of Green tensor, which is very time consuming. In electromagnetic theory, Green tensor rapidly decreases as the distance between source and field cell increases. Therefore, the source cell which are far away from the field cell does not make an effect on the electric field of the field cell. Consequently, by ignoring the effect of Green tensor due to far away source cells, computing time for electromagnetic numerical modeling can be reduced dramatically. Comparisons of this new method against a full integral equation, extended Born approximation and series code show that the method is accurate enough much less time consuming.