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1. An Integrated Modeling Framework for Application Layer Security

   Kannan U; Swamidurai R (July 2022, Neuroquantology)

   Cybersecurity is a complex problem. To study the complexity underneath the system and forecast possible future cyber events, we used system dynamics (SD)modeling and simulation.Network operations are normally modeled and simulated using the discrete-event simulation (DES) techniques. Since the primary focus of the DES modeling is packet traffic, the cyberattacks and resulting defenses are viewed from the layer 3 (network layer) of the open system interconnection (OSI) model. This does not discover more harmful attacks that might occur at higher(layer 4 and above) OSI layers. There are 32 million small businesses across the United States and 81 percent of them do not have cybersecurity personnel. Today’s extraordinary (COVID-19) situation, application layer (layer 7) security is the key concern for everyone, because every business revenue is heavily dependent on online/always-on presence. Research shows that almost 70 percent of successful cyber attacks are happening at the application layer. This paper presents a new integrated SD modeling framework for the application layer security to help small businesses from cyberattacks. 

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2. Layer-wise spatial modeling of porosity in additive manufacturing

   https://doi.org/10.1080/24725854.2018.1478169  

   Liu, Jia; Liu, Chenang; Bai, Yun; Rao, Prahalada; Williams, Christopher B.; Kong, Zhenyu (June 2018, IISE Transactions)
3. Control-Oriented Modeling and Repetitive Control in In-Layer and Cross-Layer Thermal Interactions in Selective Laser Sintering

   https://doi.org/10.1115/1.4046367  

   Wang, Dan; Jiang, Tianyu; Chen, Xu (January 2021, ASME Letters in Dynamic Systems and Control)

   null (Ed.)

   Abstract Although laser-based additive manufacturing (AM) has enabled unprecedented fabrication of complex parts directly from digital models, broader adoption of the technology remains challenged by insufficient reliability and in-process variations. In pursuit of assuring quality in the selective laser sintering (SLS) AM, this paper builds a modeling and control framework of the key thermodynamic interactions between the laser source and the materials to be processed. First, we develop a three-dimensional finite element simulation to understand the important features of the melt pool evolution for designing sensing and feedback algorithms. We explore how the temperature field is affected by hatch spacing and thermal properties that are temperature-dependent. Based on high-performance computer simulation and experimentation, we then validate the existence and effect of periodic disturbances induced by the repetitive in- and cross-layer thermomechanical interactions. From there, we identify the system model from the laser power to the melt pool width and build a repetitive control algorithm to greatly attenuate variations of the melt pool geometry. 

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4. Meso-scale modeling of multiple-layer fabrication process in Selective Electron Beam Melting: Inter-layer/track voids formation

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   Yan, Wentao; Qian, Ya; Ge, Wenjun; Lin, Stephen; Liu, Wing Kam; Lin, Feng; Wagner, Gregory J. (March 2018, Materials & Design)
5. Modeling carbon dioxide exchange in a single-layer urban canopy model

   https://doi.org/10.1016/j.buildenv.2020.107243  

   Li, Peiyuan; Wang, Zhi-Hua (October 2020, Building and Environment)

   null (Ed.)