• Journal of the Optical Society of Korea
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• 제16권3호
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• pp.215-220
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• 2012

In an earlier work, we proposed the chromatic dispersion monitoring technique of non-return to zero (NRZ) signal based on clock-frequency component (CFC) through numerical simulations. However, we have not yet shown any experimental demonstration or analytic derivation of it. In this paper, we show an experimental demonstration and analytic derivation of the proposed chromatic dispersion monitoring technique. We confirm that the experimental results and the analytic results correspond with the simulation results. We also demonstrate that monitoring range and accuracy can be improved by using a simple clock-extraction method.

• 한국수학교육학회지시리즈A:수학교육
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• 제40권1호
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• pp.113-123
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• 2001

We investigated an irrational constant e and compared its computational methods using spreadsheet. Such methods are based on classical definition, infinite series, continued fraction, infinite product exponential function and accelerated classical method. This kind of work is focused on experimental mathematics using computers in math class. This approach will be helpful for mathematics teachers to teach constant e in their classroom.

• 한국포장학회지
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• 제26권3호
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• pp.147-154
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• 2020

The purpose of this study was to research the status of logistic service-related workers about untact works by case study in the Era of COVID-19. An experimental design was used by case analysis of interviews with ten office workers from May to June 2020. The results of this research were divided into three categories: work environment, work management and work effect. First, teleworking has a significantly positive influence on business efficiency about work environment. ZOOM, One drive, Skype, Chatbot, Microsoft Teams and Remote view are used as collaborative applications. Second, work instructions in documents are needed such as e-mail and messenger using information and communication technology about work management. Third, the strong points of teleworking are both high work efficiency and job satisfaction about work effect. The weak points of teleworking are both very low-technology and misunderstanding about work effect. The result offer some insights into the case study of logistic service-related workers about untact works. Based on the results, the implications and the limitations of this study were discussed.

• International Journal of Aeronautical and Space Sciences
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• 제14권2호
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• pp.122-132
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• 2013

In this research the development of unstructured grid discretization solution techniques is presented. The purpose is to describe such a conservative discretization scheme applied for experimental validation work. The objective of this paper is to better establish the effects of mesh generation techniques on velocity fields and particle deposition patterns to determine the optimal aerodynamic characteristics. In order to achieve the objective, the mesh surface discretization approaches used the VLA prototype manufacturing tolerance zone of the outer surface. There were 3 schemes for this discretization study implementation. They are solver validation, grid convergence study and surface tolerance study. A solver validation work was implemented for the simple 2D and 3D model to get the optimum solver for the VLA model. A grid convergence study was also conducted with a different growth factor and cell spacing, the amount of mesh can be controlled. With several amount of mesh we can get the converged amount of mesh compared to experimental data. The density around surface model can be calculated by controlling the number of element in every important and sensitive surface area of the model. The solver validation work result provided the optimum solver to employ in the VLA model analysis calculation. The convergence study approach result indicated that the aerodynamic trend characteristic was captured smooth enough compared with the experimental data. During the surface tolerance scheme, it could catch the aerodynamics data of the experiment data. The discretization studies made the validation work more efficient way to achieve the purpose of this paper.

• 대한통합의학회지
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• 제8권4호
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• pp.265-275
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• 2020

Purpose : In this study, we would like to apply oral sensory play therapy program to children with cerebral palsy who have sensitive oral senses to find out the effect on oral sensory ability, oral function, performance ability and sociality. Methods : The subjects of this study were 20 children diagnosed with cerebral palsy, and 10 experimental groups and 10 control groups. Oral sensory play therapy programs, including oral sensory programs, were conducted in the experimental group, while only oral sensory programs were conducted in the control group. Oral Sensory Treatment Level was used to identify the sensory profile and the overall oral function of the oral function was used, and the performance and satisfaction of Canadian occupational performance measure (COPM) were examined to find out the performance of the work, and social skills were examined for social skills (SMS). Results : The level of oral sensory treatment, overall oral function, work performance and sociality all increased significantly in the experimental group, but the oral sense and oral function in the control group were significantly increased, but not significantly in the case of work performance and sociality. Conclusion : Through this study, we confirmed that oral sensory play therapy program is an effective arbitration method for oral sensation, oral function, work performance and social enhancement of children with cerebral palsy. Based on the results of this study, the study of arbitration protocols for children with cerebral palsy with oral sensory problems will have to be more active.

• 한국콘텐츠학회논문지
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• 제21권3호
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• pp.336-351
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• 2021

본 연구는 선호음악을 활용한 음악치료 활동이 언론사 기자의 직무스트레스, 직무열의, 번영에 미치는 효과를 알아보는데 목적이 있다. 연구 대상자는 S시에 소재한 기자 51명으로 실험집단은 A방송국의 기자 20명, 통제집단은 계열사인 A신문사의 기자 31명으로 구성되었다. 실험집단은 총 2주 동안 하루 최소 3회 이상 선호음악 감상을 자율적으로 실시하였고, 통제집단은 아무런 활동도 하지 않았다. 자료 분석을 위해 실험 시행 직전(사전)과 종료 후(사후) 각 집단의 직무스트레스 척도, 직무열의 척도, 번영척도 점수를 수집하였으며 분석한 결과는 다음과 같다. 첫째, 실험집단의 직무스트레스가 감소했으며, 통제집단과의 비교에서도 유의한 점수 차이가 나타났다. 둘째, 직무열의 또한 유의한 차이로 증가되었다. 셋째, 번영의 경우 실험집단의 사후 평균값이 소폭 상승하였으나, 그 차이는 통계적으로 유의미하지 않았다. 이상의 결과를 통해 본 연구에서는 언론사 기자의 직무스트레스 상황에서 회복을 위한 음악치료 활동 프로그램의 필요성에 대한 시사점을 제공하고 후속 연구의 필요성을 논의하였다.

• 패션비즈니스
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• 제24권4호
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• pp.63-84
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• 2020

It is essential to consider the heavy industrial working environment factors which are regarded as harmful to workers' health and safety and suitable work motion factors for the workers' motion while developing the work clothes for painting workers in the machinery and shipbuilding industries. This study suggests the use of 3D virtual clothing simulations as a solution to protect the human body from hazardous working conditions accompanying the development of painting work clothes and assessing the work motion performance associated with the comfort while workers wear them during the work clothes. The initial aim of the study is to examine a male avatar to run work motions simultaneously within a 3D virtual clothing simulator, secondly, to present the simulation images of coverall type men's painting work clothes with the application of two experimental painting work motions and one control motion to the avatar, and finally, to present the distance analysis images of the painting work clothes and the avatar body and air gap rates through the analysis of cross-sections of the avatar body while wearing the coverall work clothes according to the work motions. The results showed that the distance degree of painting work clothes to the avatar body for each part of the human body when performing painting work motions. Moreover, 3D virtual clothing simulations enabled the creation of a male model avatar to run painting work motions together and the painting work clothes developed were found to be suitable for the painting work motions.

• International Journal of Fluid Machinery and Systems
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• 제4권1호
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• pp.199-208
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• 2011

This work presents numerical results, using OpenFOAM, of the flow in the swirl flow generator test rig developed at Politehnica University of Timisoara, Romania. The work shows results computed by solving the unsteady Reynolds Averaged Navier Stokes equations. The unsteady method couples the rotating and stationary parts using a sliding grid interface based on a GGI formulation. Turbulence is modeled using the standard k-${\varepsilon}$ model, and block structured wall function ICEM-Hexa meshes are used. The numerical results are validated against experimental LDV results, and against design velocity profiles. The investigation shows that OpenFOAM gives results that are comparable to the experimental and design profiles. The unsteady pressure fluctuations at four different positions in the draft tube is recorded. A Fourier analysis of the numerical results is compared whit that of the experimental values. The amplitude and frequency predicted by the numerical simulation are comparable to those given by the experimental results, though slightly over estimated.

• Steel and Composite Structures
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• 제28권2호
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• pp.251-266
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• 2018

Compared to conventional flat web I-beams, the prediction of shear buckling stress of corrugated web steel beams (CWSBs) is not straightforward. But the CWSBs combined advantages of lightweight large spans with low-depth high load-bearing capacities justify dealing with such difficulties. This work investigates experimentally and analytically the shear strength of trapezoidal CWSBs. A set of large scale CWSBs are manufactured and tested to failure in shear. The results are compared with widely accepted CWSBs shear strength prediction models. Confirmed by the experimental results, the linear buckling analyses of trapezoidal corrugated webs demonstrated that the local shear buckling occurs only in the flat plane folds of the web, while the global shear buckling occurs over multiple folds of the web. New analytical prediction model accounting for the interaction between the local and global shear buckling of CWSBs is proposed. Experimental results from the current work and previous studies are compared with the proposed analytical prediction model. The predictions of the proposed model are significantly better than all other studied models. In light of the dispersion of test data, accuracy, consistency, and economical aspects of the prediction models, the authors recommend their proposed model for the design of CWSBs over the rest of the models.

• Nuclear Engineering and Technology
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• 제53권9호
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• pp.2830-2838
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• 2021

This work deals with the assessment of the burnup capabilities of the Serpent Monte Carlo code to predict spent nuclear fuel (SNF) isotopic concentrations for low-enriched uranium (LEU) fuel at different burnup levels up to 47 MWd/kgU. The irradiation of six UO₂ experimental samples in three different VVER-1000 reactor units has been simulated and the predicted concentrations of actinides up to ²⁴⁴Cm have been compared with the corresponding measured values. The results show a global good agreement between calculated and experimental concentrations, in several cases within the margins of the nuclear data uncertainties and in a few cases even within the reported experimental uncertainties. The differences in the performances of the JEFF3.1.1, ENDF/B-VII.1 and ENDF/B-VIII.0 nuclear data libraries (NDLs) have also been assessed and the use of the newly released ENDF/B-VIII.0 library has shown an increased accuracy in the prediction of the C/E's for some of the actinides considered, particularly for the plutonium isotopes. This work represents a step forward towards the validation of advanced simulation tools against post irradiation experimental data and the obtained results provide an evidence of the capabilities of the Serpent Monte-Carlo code with the associated modern NDLs to accurately compute SNF nuclide inventory concentrations for VVER-1000 type reactors.