• Advances in nano research
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• v.1 no.4
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• pp.203-210
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• 2013

So far, all reviews and control approaches of spin relaxation have been done on lateral single electron quantum dots. In such structures, many efforts have been done, in order to eliminate spin-lattice relaxation, to obtain equal Rashba and linear Dresselhaus parameters. But, ratio of these parameters can be adjustable up to 0.7 in a material like GaAs under high-electric field magnitudes. In this article we have proposed a single electron QD structure, where confinements in all of three directions are considered to be almost identical. In this case the effect of cubic Dresselhaus interaction will have a significant amount, which undermines the linear effect of Dresselhaus while it was destructive in lateral QDs. Then it enhances the ratio of the Rashba and Dresselhaus parameters in the proposed structure as much as required and decreases the spin states up and down mixing and the deviation angle from the net spin-down As a result to the least possible value.

• Bulletin of the Korean Chemical Society
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• v.29 no.6
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• pp.1131-1136
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• 2008

The electrical repulsive energy between two model cylinders was calculated by solving nonlinear Poission- Boltzmann (P-B) equation under Derjaguin approximation. Effects of the surface potential, Debye screening length, and configuration of cylinders on the repulsive interaction energy were examined. Due to the anisotropy of the shape of cylinder, the interaction repulsive energy showed dependence to the configuration of particles; cylinders aligned in end-to-end configuration showed largest repulsive energy and crossed particles had lowest interaction energy. The configuration effect is originated from the curvature effect of the interacting surfaces. The curved surfaces showed less repulsive energy than flat surfaces at the same interacting surface area. The configuration dependency of interaction energy agreed with the previous analytical solution obtained under the linearized P-B equation. The approach and results present in this report would be applicable in predicting colloidal behavior of cylindrical particles.

• 한국연소학회:학술대회논문집
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• 2000.12a
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• pp.113-122
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• 2000

Dynamic structures of unsteady $CH_4$/Air jet diffusion flames with flame-vortex interaction were numerically investigated. A time-dependent, axisymmetric computational model was adopted for this calculation. Two step global reaction mechanism which considers 6 species, was used to calculate the reaction rates. The predicted results including gravitational effect show that the large outer vortices and the small inner vortex street can be well simulated without any additional disturbances in the downstream of nozzle tip. It was found that the temperature and species concentrations had various values for the same mixture fraction in flame-vortex interaction region. This unsteady jet flame configuration accompanying flame-vortex interaction is expected to give good implications for the structure of turbulent flames.

• Journal of the korean Society of Automotive Engineers
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• v.14 no.2
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• pp.65-75
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• 1992

An analytical scheme for predicting the crack aspect pattern of materials which contain twin surface cracks was developed. Fatigue tests were performed on twin surface cracked PMMA plate specimens to obtain the interaction factor accounting for the interference effect of adjacent cracks. Here, the interaction factor is defined as the ratio of the stress intensity factor for twin surface cracks to that for a single surface crack. From the analysis of the fatigue test result, the interaction factor was presented as the ninth-order polynomial expression having a function of dimensionless crack spacing ratio. Then the polynomial expression was incorporated into the prediction program of the crack aspect pattern for twin surface cracked materials. And, the interaction effect and the coalescence condition of adjacent cracks were simplified in the newly developed prediction scheme of the crack aspect pattern. The predicted crack growth pattern using the prediction scheme was compared with test data from PMMA specimen. The predicted pattern agreed well with the test data.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2009.04a
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• pp.645-645
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• 2009

In many practical applications of the centrifugal fan, the impeller-diffuser interaction noise is considered as a main source of fan noise. The housing for an electric motor is also expected to play an important role on noise propagation because of its complicated configuration. This study investigates the impeller-diffuser interaction noise and its sources by computing three-dimensional, incompressible flow field of the centrifugal fan in motor housing. The effect of motor case on fan noise characteristic is then investigated using the Brinkman penalization method, while the noise source associated with impeller-diffuser interaction is mathematically modeled. It is found that the present methodology combined with mathematical description of noise source provides a fairly good agreement with the experimental results, indicating that the motor housing has significant effect on noise characteristics. Finally, aeroacoustic noise prediction for various impeller-diffuser blade count ratios is conducted for noise reduction.

• Journal of The Korean Society of Clinical Toxicology
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• v.3 no.1
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• pp.11-16
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• 2005

Chemical mixtures of components, each of which are present at less than guidance concentrations, may be hazardous due to additivity, interactions, or both. Toxicological interactions may increase the health hazard above what would be expected from an assessment of each component singly, or all components additively. So chemical mixture are a particular issue in public health. There are several approach to assess whether there are additivity or interaction in assessing toxicological effects, such as, components-based approach, physiologically-based pharmacokinetic /pharmacodynamic(PBPK/PD) models, hazard index method, and weight-of evidence method. If we consider interaction or additivity effects in assessing the health effects of chemcial mixtures, we can get more accurate information about toxicological effects and dose-response relationship in chemical mixtures.

• Journal of the Korean Ceramic Society
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• v.48 no.2
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• pp.195-199
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• 2011

The effect of copper oxide on migration and interaction of protons in barium zirconate was investigated using density functional theory. One copper atom was substituted for a zirconium atom site, and a proton was added to a $3{\times}3{\times}3$ barium zirconate superstructure. An energy barrier of 0.89 eV for proton migration was the highest among several energy barriers. To investigate the interaction between multiple protons and a copper atom, two protons were added to the superstructure. Various proton positions were determined by the interaction between the two protons and the copper atom.

• Human Ecology Research
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• v.60 no.1
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• pp.39-52
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• 2022

The purpose of this study was to investigate whether attachment to primary caregivers and family interaction affect rural children's social competence through self-regulation ability. To achieve this, a survey was conducted with 345 students aged 11-13 attending elementary schools in a rural area of Gyeongsang Province. Data were analyzed using descriptive statistics, Pearson correlation analysis, and path analysis using the AMOS 23.0 program. The main result was that rural children's self-regulation had an indirect effect on attachment with primary caregivers and family interaction through social competence. The findings of this study will contribute to designing a variety of programs that can promote the positive development of social competence among rural children.

• Journal of Korean Academy of Nursing
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• v.32 no.6
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• pp.823-831
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• 2002

This study is attempts to clarify the effect of infant massage for the promotion of primipara's mother-infant interaction Method: The term for collecting data for experimental group ranged from April 25, 2001 to June 5, 2001. The infants for this group were sampled among normal mother-infant from one postpartum care center located in J city. The term for collecting data for control group ranged from June 10, 2001 to August 3, 2001. The infants for this group were sampled among normal mothers infant from 1 general hospital, 1 university hospital and 1 postpartum care center located in J city. The experiment was implemented giving primipara education about massage based on protocol for infant massage provided by Johnson & Johnson Korea and they received 10 days of education, 10 minutes a day (from 10 to 11 a.m) In the post test, we videotaped both the control group and the experimental group visiting their homes 4 weeks after delivery to observe mother-infant play interaction. Data analysis was done using SAS and the homogeneity between general properties owned by both control group and experimental group and mother's perception scale for children was verified through -test. Mother-infant play interaction with both control group and experimental group was analyzed through t-test in the experiment. And analysis of mother-infant interaction points based on general properties was made using ANOVA and t-test. Result: Hypothesis that mother-infant play interaction with primipara who gave her infant a massage will be more active than that of the primipara who didn't was verified (t= -4.27, p=.0001). And the points in each item, points in each item were estimated as follows. Mother behavioral items (t=-4.96, p=.0001), infant behavioral item (t=-0.36, p=.71), mother-infant interaction reciprocity (t=-2.64, p=.01). Conclusion: An infant massage program can contribute to promoting the Mother-Infant Play Interaction positively.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.155.3-155
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• 2001

Researches of multi-robot system are active in these days. The most remarkable characteristic of multirobot system is that the robots work cooperatively and achieve the task which a single robot cannot do. It is essential to investigate number effect of multi-robot system. In this paper, we chose foraging task and investigated their behavior. At first, we investigated the foraging behavior in case that interaction range is Infinite. Secondly, we investigated the behavior in case that interaction range is finite. In both case, we find out there is an optimum interaction duration.