• Title/Summary/Keyword: fractional-order system

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Artificial intelligence design for dependence of size surface effects on advanced nanoplates through theoretical framework

  • Na Tang;Canlin Zhang;Zh. Yuan;A. Yvaz
    • Steel and Composite Structures
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    • v.52 no.6
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    • pp.621-626
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    • 2024
  • The work researched the application of artificial intelligence to the design and analysis of advanced nanoplates, with a particular emphasis on size and surface effects. Employing an integrated theoretical framework, this study developed a more accurate model of complex nanoplate behavior. The following analysis considers nanoplates embedded in a Pasternak viscoelastic fractional foundation and represents the important step in understanding how nanoscale structures may respond under dynamic loads. Surface effects, significant for nanoscale, are included through the Gurtin-Murdoch theory in order to better describe the influence of surface stresses on the overall behavior of nanoplates. In the present analysis, the modified couple stress theory is utilized to capture the size-dependent behavior of nanoplates, while the Kelvin-Voigt model has been incorporated to realistically simulate the structural damping and energy dissipation. This paper will take a holistic approach in using sinusoidal shear deformation theory for the accurate replication of complex interactions within the nano-structure system. Addressing different aspectsof the dynamic behavior by considering the length scale parameter of the material, this work aims at establishing which one of the factors imposes the most influence on the nanostructure response. Besides, the surface stresses that become increasingly critical in nanoscale dimensions are considered in depth. AI algorithms subsequently improve the prediction of the mechanical response by incorporating other phenomena, including surface energy, material inhomogeneity, and size-dependent properties. In these AI- enhanced solutions, the improvement of precision becomes considerable compared to the classical solution methods and hence offers new insights into the mechanical performance of nanoplates when applied in nanotechnology and materials science.

The New Etiologic Classification System of Korean Medicine (새로운 한의학 병인분류체계의 연구)

  • Park, Hae Mo;Lee, Kinam;Hwang, Guiseo;Shin, Yongchul;Go, Sunggyu;Lee, Haewoong;Lee, Youngjun;Lim, Byungmook;Lee, Sangjae;Jung, Myungsu;Jang, Bohyung;Park, Sunju;Lee, Sundong
    • Journal of Society of Preventive Korean Medicine
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    • v.17 no.2
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    • pp.47-68
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    • 2013
  • Objectives : This research aimed to develop a new etiologic classification for traditional Korean Medicine in order to respond to the social and environmental change. Methods : We reviewed the existing theories on etiological classification for East Asian Medicine thoroughly and discussed the problems and limitations. Based on the experts' consensus, we abstracted disease factors and etiologic items. Results : The disease factors are classified into three parts: the human body, the environment, and the interaction between the human body and the environment. We defined them as the inner factor, the external factor, and the interaction between the inner and the external factors. The inner factor is free from the influence of the environment, and it causes diseases solely from the components of the human body. It is divided into genetic factors. The external factor is defined as a case when a disease occurs due to a factor outside the human body and includes external injuries, environmental pollution, and natural disasters. The interaction between the inner and the external factors is a disease factor that causes diseases by the interaction of the human body and the environment and includes emotions, habits, and social environment. As a result of the analysis, it was possible to see the meanings at a single glance as the scattered and fractional meanings were integrated with focus on medicinal herbs, but the increasing number of analyzed medicinal herbs tended to more and more complicate their relationships, thus, requiring additional work like filtering. Conclusions : The new etiologic classification of Korean Medicine fully reflects the perspectives on life in Korean Medicine while embracing the changes in modem society. Also, by avoiding the usage of ambivalent terms and wrong classification methods, the new classification system constructs intuitive and concise etiology and improves usability in clinical medicine.

Characteristics of Water Level and Velocity Changes due to the Propagation of Bore (단파의 전파에 따른 수위 및 유속변화의 특성에 관한 연구)

  • Lee, Kwang Ho;Kim, Do Sam;Yeh, Harry
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.28 no.5B
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    • pp.575-589
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    • 2008
  • In the present work, we investigate the hydrodynamic behavior of a turbulent bore, such as tsunami bore and tidal bore, generated by the removal of a gate with water impounded on one side. The bore generation system is similar to that used in a general dam-break problem. In order to the numerical simulation of the formation and propagation of a bore, we consider the incompressible flows of two immiscible fluids, liquid and gas, governed by the Navier-Stokes equations. The interface tracking between two fluids is achieved by the volume-of-fluid (VOF) technique and the M-type cubic interpolated propagation (MCIP) scheme is used to solve the Navier-Stokes equations. The MCIP method is a low diffusive and stable scheme and is generally extended the original one-dimensional CIP to higher dimensions, using a fractional step technique. Further, large eddy simulation (LES) closure scheme, a cost-effective approach to turbulence simulation, is used to predict the evolution of quantities associated with turbulence. In order to verify the applicability of the developed numerical model to the bore simulation, laboratory experiments are performed in a wave tank. Comparisons are made between the numerical results by the present model and the experimental data and good agreement is achieved.

Impact of Emission Inventory Choices on PM10 Forecast Accuracy and Contributions in the Seoul Metropolitan Area (배출량 목록에 따른 수도권 PM10 예보 정합도 및 국내외 기여도 분석)

  • Bae, Changhan;Kim, Eunhye;Kim, Byeong-Uk;Kim, Hyun Cheol;Woo, Jung-Hun;Moon, Kwang-Joo;Shin, Hye-Jung;Song, In Ho;Kim, Soontae
    • Journal of Korean Society for Atmospheric Environment
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    • v.33 no.5
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    • pp.497-514
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    • 2017
  • This study quantitatively analyzes the effects of emission inventory choices on the simulated particulate matter (PM) concentrations and the domestic/foreign contributions in the Seoul Metropolitan Area (SMA) with an air quality forecasting system. The forecasting system is composed of Weather Research and Forecasting (WRF)-Sparse Matrix Operator Kernel Emissions (SMOKE)-Community Multi-Scale Air Quality (CMAQ). Different domestic and foreign emission inventories were selectively adopted to set up four sets of emissions inputs for air quality simulations in this study. All modeling cases showed that model performance statistics satisfied the criteria levels (correlation coefficient >0.7, fractional error <50%) suggested by previous studies. Notwithstanding the apparently good model performance of total PM concentrations by all emission cases, annual average concentrations of simulated total PM concentrations varied up to $20{\mu}g/m^3$ (160%) depending on the combination of emission inventories. In detail, the difference in simulated annual average concentrations of the primary PM coarse (PMC) was up to $25.2{\mu}g/m^3$ (6.5 times) compared with other cases. Furthermore, model performance analyses on PM species showed that the difference in the simulated primary PMC led to gross model overestimation in general, which indicates that the primary PMC emissions need to be improved. The contribution analysis using model direct outputs indicated that the domestic contributions to the annual average PM concentrations in the SMA vary from 44% to 67%. To account for the uncertainty of the simulated concentration, the contribution correction factor method proposed by Bae et al. (2017) was applied, which resulted in converged contributions(from 48% to 57%). We believe this study shows that it is necessary to improve the simulated concentrations of PM components in order to enhance the accuracy of the forecasting model. It is deemed that these improvements will provide more accurate contribution results.