• Child Health Nursing Research
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• v.18 no.2
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• pp.76-84
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• 2012

Purpose: This study was done to develop a cell phone addiction scale for Korean children. Methods: The process included construction of a conceptual framework, generation of initial items, verification of content validity, selection of secondary items, preliminary study, and extraction of final items. The participants were 268 children from grades 4 to 6 in two urban elementary schools. Construct validity, internal consistence reliability, and split-half reliability were used to analyze the data. Results: Nine items were categorized into 2 factors explaining 61.29% of total variance. The factors were labeled as obsessive compulsion (6 items) and dependency (3 items). Cronbach's alpha coefficient for the 9 items was .87, and Spearman-Brown coefficient was .83. Scale scores identified children as high risk users, at risk users, or average users by standard scores. Conclusion: The above findings indicate that the cell phone addiction scale for children has good validity and reliability when used with Korean children.

• Journal of the Korean Vacuum Society
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• v.12 no.S1
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• pp.116-119
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• 2003

$Ni_2$MnGa films, deposited on mica and glass substrates, were studied by ferromagnetic resonance (FMR) technology. The temperature-dependent resonance field was measured and a martensitic phase transformation (MT) was found between 310 and 340 K, exhibiting an abnormality on the curve. The easy axis is found to be in the film plane. The line width increases as a whole with decreasing temperature, which is discussed in terms of the motional narrowing mechanism. The resonance field was also measured as a function of orientation and the results were fitted, exhibiting a good consistence.

• 전기의세계
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• v.39 no.4
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• pp.52-56
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• 1990

플라즈마를 도전성 유체라고 생각한다면 외부에서 인가된 전자장이 있을때 전기장에 의해 전류가 생성이 되고, 이전류에 의해 자기장이 다시 생성되기 때문에 플라즈마 내에서는 self-consistence 한 전자장을 구한다는 것은 상당히 난해한 문제가 될 수 있다. 초고온 핵융합 플라즈마의 연구는 대용량 컴퓨터를 이용한 수치 해석적인 방법이 없이는 불가능할 정도로 중요하게 이용되고 있다. 최근에 그 이용 범위가 급속도로 널리 퍼지고 있는 저오니 플라즈마의 경우, 내부에서 일어나는 복잡한 전리, 재결합, 여기 반응 등에 대한 이해가 없이 이용되고 있으나 더욱 정교한 제어가 요구되면서 이들 반응에 대한 이해가 필요하게 되었다. 이를 위해서 최근에 모델링에 관한 연구가 시도되기 시작하고 있다. 최근에 컴퓨터 용량 및 연산 속도의 급속한 증가가 종래에 불가능하게 여겨졌던 플라즈마 현상을 수치해석을 통해 이해가 가능하게 도와주고 있으며 앞으로 플라즈마 연구에 있어서 그 중요성이 더욱 커지리라 생각된다.

• Journal of Elementary Mathematics Education in Korea
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• v.21 no.3
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• pp.443-460
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• 2017

The aim of this study was to develop and validate a mathematics teaching efficacy scale for South Korean Elementary Teachers. The sample was consisted of 300 elementary teachers in South Korea. A total of 13 items were developed and examined for internal consistence. The results of this study showed that the proposed scale was appropriate to represent mathematics teaching efficacy of elementary teachers.

• Journal of Biosystems Engineering
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• v.30 no.5 s.112
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• pp.312-317
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• 2005

A flow injection type biosensor was tested to confirm the performance of a batch and a continuous type flow injection unit. Reproducibility and consistence of the biosensor were investigated to determine the effect of pulsations and air bubbles, and the applicability of on-line monitoring. The air bubbles affected the performance of the sensor irrespective of the location, and also the pulsations of the pump influenced the performance of the sensor. The applicability of on-line motoring was accepted as the result of the repeated and long-term measurements.

• Journal of the Korea Institute of Military Science and Technology
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• v.2 no.2
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• pp.92-98
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• 1999

Dynamic behavior of missile which is fired in canister is analyzed by flexible multibody dynamics. The bending elasticity of missile is very important in case that missile is fired in the inclined launcher. In this paper, the force element model for the missile launching stage and the finite element model of missile are developed. The FEA model of missile is condensed into five lumped mass element model and the consistence between FE model and lumped mass model of missile is verified by modal analysis. As a result of analysis, sabot reaction force and pitch rate of missile for the variation of gap size and force element are obtained.

• Bulletin of the Korean Chemical Society
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• v.16 no.7
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• pp.649-653
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• 1995

Solution-state structure of native F430 was determined by using NMR methods and NMR-based distance geometry (DG) computations. Structures were generated with loose NOE-derived interproton distance restraints (2.0-2.5 Å, 2.0-3.5 Å and 2.0-4.5 Å for strong, medium, and weak NOE cross-peak intensities, respectively). 2D NOESY back-calculations of structures were subsequently carried out for establishing the consistence between experimental data and DG-model structures. The back-calculated 2D NOESY spectra of resulting DG structures were well consistent with experimental 2D NOESY spectra. Superposition of 20 independent structures with macrocyclic ring atoms and all atoms of F430 afforded pairwise root mean square deviations (RMSD) of 0.025-0.125 Å and 0.64-1.3 Å, respectively. The macrocyclic rings of structures are well converged to a unique conformation with saddle-shaped deformation whereas most of side chains are not converged. The average dihedral angle (N1-N2-N3-N4, 27.78±1.50°) of 20 DG-structures exhibits that the macrocyclic ring conformation is puckered as much as 12,13-diepimeric F430 (28.75±4.07°).

• Interaction and multiscale mechanics
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• v.5 no.2
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• pp.145-155
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• 2012

The thin-plate structure and the box-beam structure are two typical welded structures in railway vehicles. Because of their structure complexity, bigger size and multi-seams, welding residual distortion which occur in welding process bring unfavorable effect on the quality of welding products manufacturing and service. As a result, welding distortion forecasting and control become an important and urgent research topic in railway vehicles. In this paper, three different numerical methods are presented corresponding to three typical types of welded structures of railway vehicles and welding deformation are simulated. Consistence of numerical results and experimental data proves the correctness of models and feasibility of simulation methods.

• Transactions of Materials Processing
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• v.27 no.6
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• pp.363-369
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• 2018

This study measured the mechanical properties of an ash wood under various temperature and humidity conditions and a finite element model was developed to predict the behavior of the wood. A humidity-controlled chamber was developed and used for measuring the dimensional changes of woods under various humidity conditions. The thermal expansion coefficient and the elastic stiffness constants were measured by using a thermal chamber and the three-point bending test along the three principal axes of the wood. A constitutive model was proposed to describe the moisture content and temperature dependent behavior of wood. The proposed model was validated for the warping test of a wood plate. The warping of the plate was calculated using the finite element method. The calculated amount of warping was in consistence with the measurements.

• Nuclear Engineering and Technology
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• v.53 no.1
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• pp.19-29
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• 2021

This paper presents the validation of the MCS code for critical safety analysis with burnup credit for the spent fuel casks. The validation process in this work considers five critical benchmark problem sets, which consist of total 80 critical experiments having MOX fuels from the International Criticality Safety Benchmark Evaluation Project (ICSBEP). The similarity analysis with the use of sensitivity and uncertainty tool TSUNAMI in SCALE was used to determine the applicable benchmark experiments corresponding to each spent fuel cask model and then the Upper Safety Limits (USLs) except for the isotopic validation were evaluated following the guidance from NUREG/CR-6698. The validation process in this work was also performed with the MCNP6 for comparison with the results using MCS calculations. The results of this work showed the consistence between MCS and MCNP6 for the MOX fueled criticality benchmarks, thus proving the reliability of the MCS calculations.