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1. Modeling of Welded Joints in a Pyramidal Truss Sandwich Panel Using Beam and Shell Finite Elements

   https://doi.org/10.1115/1.4048792  

   Yuan, Ke; Zhu, Weidong (August 2021, Journal of Vibration and Acoustics)

   null (Ed.)

   Abstract Pyramidal truss sandwich panels (PTSPs) are widely used in engineering structures and their face sheets and core parts are generally bonded by the welding process. A large number of solid elements are usually required in the finite element (FE) model of a PTSP with welded joints to obtain its accurate modal parameters. Ignoring welded joints of the PTSP can save many degrees of freedom (DOFs), but significantly change its natural frequencies. This study aims to accurately determine modal parameters of a PTSP with welded joints with much fewer DOFs than those of its solid element model and to obtain its operational modal analysis results by avoiding missing its modes. Two novel methods that consider welded joints as equivalent stiffness are proposed to create beam-shell element models of the PTSP. The main step is to match stiffnesses of beam and shell elements of a welded joint with those of its solid elements. Compared with the solid element model of the PTSP, its proposed models provide almost the same levels of accuracy for natural frequencies and mode shapes for the first 20 elastic modes, while reducing DOFs by about 98% for the whole structure and 99% for each welded joint. The first 14 elastic modes of a PTSP specimen that were measured without missing any modes by synchronously capturing its two-faced vibrations through use of a three-dimensional scanning laser vibrometer (SLV) and a mirror experimentally validate its beam-shell element models created by the two proposed methods. 

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2. Security and Privacy Issues in Intelligent Transportation Systems: Classification and Challenges

   https://doi.org/10.1109/MITS.2019.2898973  

   Dalton A. Hahn, Arslan Munir (April 2021, IEEE intelligent transportation systems magazine)

   null (Ed.)

   Intelligent Transportation Systems (ITS) aim at integrating sensing, control, analysis, and communication technologies into travel infrastructure and transportation to improve mobility, comfort, safety, and efficiency. Car manufacturers are continuously creating smarter vehicles, and advancements in roadways and infrastructure are changing the feel of travel. Traveling is becoming more efficient and reliable with a range of novel technologies, and research and development in ITS. Safer vehicles are introduced every year with greater considerations for passenger and pedestrian safety, nevertheless, the new technology and increasing connectivity in ITS present unique attack vectors for malicious actors. Smart cities with connected public transportation systems introduce new privacy concerns with the data collected about passengers and their travel habits. In this paper, we provide a comprehensive classification of security and privacy vulnerabilities in ITS. Furthermore, we discuss challenges in addressing security and privacy issues in ITS and contemplate potential mitigation techniques. Finally, we highlight future research directions to make ITS more safe, secure, and privacy-preserving. 

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3. Data poisoning attacks in intelligent transportation systems: A survey

   https://doi.org/10.1016/j.trc.2024.104750  

   Wang, Feilong; Wang, Xin; Ban, Xuegang Jeff (August 2024, Transportation Research Part C: Emerging Technologies)

   Emerging technologies drive the ongoing transformation of Intelligent Transportation Systems (ITS). This transformation has given rise to cybersecurity concerns, among which data poisoning attack emerges as a new threat as ITS increasingly relies on data. In data poisoning attacks, attackers inject malicious perturbations into datasets, potentially leading to inaccurate results in offline learning and real-time decision-making processes. This paper concentrates on data poisoning attack models against ITS. We identify the main ITS data sources vulnerable to poisoning attacks and application scenarios that enable staging such attacks. A general framework is developed following rigorous study process from cybersecurity but also considering specific ITS application needs. Data poisoning attacks against ITS are reviewed and categorized following the framework. We then discuss the current limitations of these attack models and the future research directions. Our work can serve as a guideline to better understand the threat of data poisoning attacks against ITS applications, while also giving a perspective on the future development of trustworthy ITS. Emerging technologies drive the ongoing transformation of Intelligent Transportation Systems (ITS). This transformation has given rise to cybersecurity concerns, among which data poisoning attack emerges as a new threat as ITS increasingly relies on data. In data poisoning attacks, attackers inject malicious perturbations into datasets, potentially leading to inaccurate results in offline learning and real-time decision-making processes. This paper concentrates on data poisoning attack models against ITS. We identify the main ITS data sources vulnerable to poisoning attacks and application scenarios that enable staging such attacks. A general framework is developed following rigorous study process from cybersecurity but also considering specific ITS application needs. Data poisoning attacks against ITS are reviewed and categorized following the framework. We then discuss the current limitations of these attack models and the future research directions. Our work can serve as a guideline to better understand the threat of data poisoning attacks against ITS applications, while also giving a perspective on the future development of trustworthy ITS. 

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4. Towards a mechanistic understanding of competence: a missing link in diversity–disease research

   https://doi.org/10.1017/S0031182020000943  

   Stewart Merrill, Tara E.; Johnson, Pieter T. (September 2020, Parasitology)

   null (Ed.)

   Abstract Biodiversity loss may increase the risk of infectious disease in a phenomenon known as the dilution effect. Circumstances that increase the likelihood of disease dilution are: (i) when hosts vary in their competence, and (ii) when communities disassemble predictably, such that the least competent hosts are the most likely to go extinct. Despite the central role of competence in diversity–disease theory, we lack a clear understanding of the factors underlying competence, as well as the drivers and extent of its variation. Our perspective piece encourages a mechanistic understanding of competence and a deeper consideration of its role in diversity–disease relationships. We outline current evidence, emerging questions and future directions regarding the basis of competence, its definition and measurement, the roots of its variation and its role in the community ecology of infectious disease. 

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5. The cytoplasmic tail of the mechanosensitive channel Pkd2 regulates its internalization and clustering in eisosomes

   https://doi.org/10.1242/260598  

   Malla, Mamata; Sinha, Debatrayee; Chowdhury, Pritha; Bisesi, Benjamin Thomas; Chen, Qian (June 2023, Journal of Cell Science)

   ABSTRACT Polycystins are a family of conserved ion channels, mutations of which lead to one of the most common human genetic disorders, namely, autosomal dominant polycystic kidney disease. Schizosacchromyces pombe possesses an essential polycystin homologue, Pkd2, which directs Ca2+ influx on the cell surface in response to membrane tension, but its structure remains unsolved. Here, we analyzed the structure–function relationship of Pkd2 based on its AlphaFold-predicted structure. Pkd2 consists of three domains, the extracellular lipid-binding domain (LBD), nine-helix transmembrane domain (TMD) and C-terminal cytoplasmic domain (CCD). Our genetic and microscopy data revealed that LBD and TMD are essential for targeting Pkd2 to the plasma membrane from the endoplasmic reticulum. In comparison, CCD ensures the polarized distribution of Pkd2 by promoting its internalization and preventing its clustering in the eisosome, a caveolae-like membrane compartment. The domains of Pkd2 and their functions are conserved in other fission yeast species. We conclude that both extracellular and cytoplasmic domains of Pkd2 are crucial for its intracellular trafficking and function. We propose that mechanosensitive channels can be desensitized through either internalization or clustering in low-tension membrane compartments. 

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