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A Study on the Direction of Christian education in the Age of hyper connectivity Society (초연결성 사회에서의 기독교교육 방향 모색)

  • Chung, Ha Eun
    • Journal of Christian Education in Korea
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    • v.71
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    • pp.371-399
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    • 2022
  • The era we are living in is an era of hyperconnectivity where boundaries and limitations of each field and domain disappear and organically converge and share with each other. Christians living in the age of hyperconnectivity are losing their direction of life due to various divisions and severances, such as holiness and secularity, church and world, soul and body, faith and life, and humans and nature. However, in a hyperconnected society, it is necessary to break free from division and conflict caused by disconnection, and realize the kingdom of God through connection and solidarity between humans, nature, and the world. In order to explore the direction of Christian education for this purpose, this study examined the characteristics of the era of hyperconnectivity and the principle of solidarity, which is the core of hyperconnectivity. The theological meaning of solidarity was examined in terms of humans, nature, and the world, and based on this understanding, the direction of Christian education in the era of hyperconnectivity was sought. It can be summarized as having a religious understanding of human beings of Homoconnectus with a pericoretic mode of existence. Third, education on the kingdom of justice and peace where we can live together in a solidarity relationship can be summarized.

Study on Prediction of Net Thrust of Multi-Pod-Driven Ice-Breaking Vessel Under Bollard Pull and Overload Conditions According to the Change of Water Depth Using Computational Fluid Dynamics-Based Simulations (수심 변화에 따른 볼라드 당김 및 과부하 조건에서의 다중 포드 추진 쇄빙선박의 여유추력 추정에 대한 수치해석적 연구)

  • Kim, JinKyu;Kim, Hyoung-Tae;Kim, Hee-Taek;Lee, Hee-Dong
    • Journal of the Society of Naval Architects of Korea
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    • v.58 no.3
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    • pp.158-166
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    • 2021
  • In this paper, a numerical analysis technique using a body force model is investigated to estimate the available net thrust of multi-pod-driven ice-breaking vessels under bollard pull and overload conditions. To employ the body force model in present flow simulations, drag and thrust components acting on the pod unit are calculated by using Propeller Open Water (POW) test data. The available net thrusts according to the direction of operation are evaluated in both bollard pull and overload conditions under deep water. The simulation results are compared with the model test data. The available net thrusts, calculated by the present analysis for ahead operating modes at 3~6 knots which are typical speeds of the target vessel in arctic field, are agreed well with the model test results. It is also found that the present result for astern operating mode appears approximately 6 % larger than the model test result. In addition, the available net thrusts are calculated under the both operating conditions accompanied by shallow water effects, and the main cause of the difference is studied. Based on the result of the present study, it is confirmed that the body force model can be applied to the performance evaluation of multi-pod propulsion system and the main engine selection in early design stage of the vessel.

A Study on H-polarized Electromagnetic Scattering by a Resistive Strip Grating Between a Grounded Double Dielectric Layer (접지된 2중 유전체층 사이의 저항띠 격자구조에 의한 H-polarized 전자파 산란에 관한 연구)

  • Yoon, Uei-Joong
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.22 no.1
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    • pp.29-34
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    • 2022
  • In this paper, thr H-polarized scattering problems by a resistive strip grating in a grounded double dielectric layer are analyzed by applying the PMM(point matching method) known as a numerical method of electromagnetic fileld. The boundary conditions are applied to obtain the unknown field coefficients, the scattered electromagnetic fields are expanded in a series of Floquet mode functions, and the resistive boundary condition is applied to analysis of the resistive strip. The %error of the convergence of the reflected power according to the relative permittivity of the dielectric layer and the size of the number of rows in the square matrix was compared, as the size of the number of rows in the square matrix increased, the accuracy of the reflected power increased. As the resistivity of the resistive strip decreased, the thickness of the dielectric layers decreased, and the relative permittivity of the dielectric layers increased, the reflected power increased. The numerical results for the presented structure of this paper having a grounded double dielectric layer are shown in good agreement compared to those of the existing papers.

3D Ultrasound Panoramic Image Reconstruction using Deep Learning (딥러닝을 활용한 3차원 초음파 파노라마 영상 복원)

  • SiYeoul Lee;Seonho Kim;Dongeon Lee;ChunSu Park;MinWoo Kim
    • Journal of Biomedical Engineering Research
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    • v.44 no.4
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    • pp.255-263
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    • 2023
  • Clinical ultrasound (US) is a widely used imaging modality with various clinical applications. However, capturing a large field of view often requires specialized transducers which have limitations for specific clinical scenarios. Panoramic imaging offers an alternative approach by sequentially aligning image sections acquired from freehand sweeps using a standard transducer. To reconstruct a 3D volume from these 2D sections, an external device can be employed to track the transducer's motion accurately. However, the presence of optical or electrical interferences in a clinical setting often leads to incorrect measurements from such sensors. In this paper, we propose a deep learning (DL) framework that enables the prediction of scan trajectories using only US data, eliminating the need for an external tracking device. Our approach incorporates diverse data types, including correlation volume, optical flow, B-mode images, and rawer data (IQ data). We develop a DL network capable of effectively handling these data types and introduce an attention technique to emphasize crucial local areas for precise trajectory prediction. Through extensive experimentation, we demonstrate the superiority of our proposed method over other DL-based approaches in terms of long trajectory prediction performance. Our findings highlight the potential of employing DL techniques for trajectory estimation in clinical ultrasound, offering a promising alternative for panoramic imaging.

Prediction of Plant Operator Error Mode (원자력발전소 운전원의 오류모드 예측)

  • Lee, H.C.;E. Hollnagel;M. Kaarstad
    • Proceedings of the ESK Conference
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    • 1997.04a
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    • pp.56-60
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    • 1997
  • The study of human erroneous actions has traditionally taken place along two different lines of approach. One has been concerned with finding and explaining the causes of erroneous actions, such as studies in the psychology of "error". The other has been concerned with the qualitative and quantitative prediction of possible erroneous actions, exemplified by the field of human reliability analysis (HRA). Another distinction is also that the former approach has been dominated by an academic point of view, hence emphasising theories, models, and experiments, while the latter has been of a more pragmatic nature, hence putting greater emphasis on data and methods. We have been developing a method to make predictions about error modes. The input to the method is a detailed task description of a set of scenarios for an experiment. This description is then analysed to characterise thd nature of the individual task steps, as well as the conditions under which they must be carried out. The task steps are expressed in terms of a predefined set of cognitive activity types. Following that each task step is examined in terms of a systematic classification of possible error modes and the likely error modes are identified. This effectively constitutes a qualitative analysis of the possibilities for erroneous action in a given task. In order to evaluate the accuracy of the predictions, the data from a large scale experiment were analysed. The experiment used the full-scale nuclear power plant simulator in the Halden Man-Machine Systems Laboratory (HAMMLAB) and used six crews of systematic performance observations by experts using a pre-defined task description, as well as audio and video recordings. The purpose of the analysis was to determine how well the predictions matiched the actually observed performance failures. The results indicated a very acceptable rate of accuracy. The emphasis in this experiment has been to develop a practical method for qualitative performance prediction, i.e., a method that did not require too many resources or specialised human factors knowledge. If such methods are to become practical tools, it is important that they are valid, reliable, and robust.

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Petrology and geochemistry of the Seoul granitic batholith (서울 화강암질 저반의 암석학 및 지구화학)

  • Kwon, S.T.;Cho, D.L.;Lan, C.Y.;Shin, K.B.;Lee, T.;Mertzman, S.A.
    • The Journal of the Petrological Society of Korea
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    • v.3 no.2
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    • pp.109-127
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    • 1994
  • We report field relationship, petrography and major and trace element chemistry for the central part of the Seoul granitic bathlith of Jurassic age occurring in the Kyonggi massif. The batholith consists mainly of biotite granite (BG) and garnet biotite granite (GBG) with minor tonalite-quartz diorite and biotite granodiorite with or without hornblende. The mode data, along with the those reported by Hong (1984) for the biotite granite (south-BG) in the southern part of the batholith, indicate that the many of BGs and majority of GBG and south-BG are leucocratic. Major element data indicate that these predominant rocks of the batholith are peraluminous. Variation trends in Harker diagrams for the major and trace elements suggest that the BG and GBG are not related by a simple crystal fractionation process. The same is true between the central (BG and GBG) and the southern (south-BG) parts of the batholith, suggesting that the central and southern parts of the Seoul batholith may consist of three separate intrusions. Tectonic discriminations using major and trace element data and the age of emplacement suggest that the batholith represents Jurassic plutonism related to an orogeny, perhaps to a subduction-related continental magmatic arc.

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Numerical investigation on the flow noise reduction due to curved pipe based on wavenumber-frequency analysis in pressure relief valve pipe system (감압 밸브 배관 시스템 내 파수-주파수 분석을 통한 곡관의 유동소음 저감에 대한 수치적 연구)

  • Garam, Ku;Cheolung, Cheong
    • The Journal of the Acoustical Society of Korea
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    • v.41 no.6
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    • pp.705-712
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    • 2022
  • A sudden pressure drop caused by the pressure relief valve acts as a strong noise source and propagates the compressible pressure fluctuation along the pipe wall, which becomes a excitation source of Acoustic Induced Vibration (AIV). Therefore, in this study, the numerical methodology is developed to evaluate the reduction effect of compressible pressure fluctuation due to curved pipe in the pressure relief valve system. To describe the acoustic wave caused by density fluctuation, unsteady compressible Large Eddy Simulation (LES) technique, which is high accuracy numerical method, Smagorinsky-Lilly subgrid scale model is applied. Wavenumber-frequency analysis is performed to extract the compressible pressure fluctuation component, which is propagated along the pipe, from the flow field, and it is based on the wall pressure on the upstream and downstream pipe from the curved pipe. It is shown that the plane wave and the 1st mode component in radial direction are dominant along the downstream direction, and the overall acoustic power was reduced by 3 dB through the curved pipe. From these results, the noise reduction effect caused by curved pipe is confirmed.

Solution of TE Scattering Applying FGMM for Resistive Strip Grating Between a Grounded Double Dielectric Layer (접지된 2중 유전체층 사이의 저항띠 격자에 대해 FGMM을 적용한 TE 산란 해)

  • Uei-Joong Yoon
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.23 no.3
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    • pp.71-76
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    • 2023
  • In this paper, TE(transverse electric) scattering problems by a resistive strip grating between a grounded double dielectric layer are analyzed by applying the FGMM(fourier galerkin moment method) known as a numerical method of electromagnetic fileld. The boundary conditions are applied to obtain the unknown field coefficients, the scattered electromagnetic fields are expanded in a series of Floquet mode functions, and the resistive boundary condition is applied to analysis of the resistive strip. Overall, as the resistivity decreased, the magnitude of the current density induced in the resistive strip increased, and the reflected power also increased. In case of uniform resistivity, the reflected power decreased as the relative permittivity of the dielectric layers increased or the thickness of the dielectric layer increased. The numerical results for the presented structure in this paper are shown in good agreement compared to those of the existing papers.

Solution of TE Scattering by a Resistive Strip Grating Between a Double Dielectric Layer Using FGMM (FGMM을 이용한 2중 유전체층 사이의 저항띠 격자구조에 의한 TE 산란 해)

  • Uei-Joong Yoon
    • The Journal of the Convergence on Culture Technology
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    • v.9 no.3
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    • pp.619-624
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    • 2023
  • In this paper, TE(transverse electric) scattering problems by a resistive strip grating between a double dielectric layer are analyzed by using the FGMM(fourier galerkin moment method) known as a numerical method of electromagnetic fileld. The boundary conditions are applied to obtain the unknown field coefficients, the scattered electromagnetic fields are expanded in a series of Floquet mode functions, and the resistive boundary condition is applied to analysis of the resistive strip. In order to deal with the problem of the double dielectric layer, numerical calculation was performed only when the thickness and relative permittivity of the dielectric layers had the same value. Overall, as the resistivity of the uniform resistivity increased, the current density induced in the resistive strip decreased, the reflected power decreased, and the transmitted power relatively increased. The numerical results of the structure proposed in this paper are shown in good agreement compared to the results of PMM, a numerical analysis method of the existing paper.

Solution of E-polarized Scattering by a Resistive Strip Grating Between a Double Dielectric Layer Using FGMM (FGMM을 이용한 2중 유전체층 사이의 저항띠 격자구조에 의한 TM 산란 해)

  • Uei-Joong Yoon
    • The Journal of the Convergence on Culture Technology
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    • v.9 no.3
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    • pp.641-646
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    • 2023
  • In this paper, TM(transverse magnetic) scattering problems by a resistive strip grating between a double dielectric layer are analyzed by using the FGMM(fourier galerkin moment method) known as a numerical method of electromagnetic fileld. The boundary conditions are applied to obtain the unknown field coefficients, the scattered electromagnetic fields are expanded in a series of Floquet mode functions, and the resistive boundary condition is applied to analysis of the resistive strip. Overall, as the uniform resistivity of the resistive strip increased, the size of the current density induced in the resistance band decreased, the reflected power decreased, and the transmitted power increased. In addition, As the thickness of the dielectric layer increased, the reflected power increased and the transmitted power relatively decreased. The numerical results of the structure proposed in this paper are shown in good agreement compared to the results of PMM, a numerical analysis method of the existing paper.