As Vehicle-to-Everything (V2X) communication technologies gain prominence, ensuring human safety from radiofrequency (RF) electromagnetic fields (EMF) becomes paramount. This study critically examines human RF exposure in the context of ITS-5.9 GHz V2X connectivity, employing a combination of numerical dosimetry simulations and targeted experimental measurements. The focus extends across Road-Side Units (RSUs), On-Board Units (OBUs), and, notably, the advanced vehicular technologies within a Tesla Model S, which includes Bluetooth, Long Term Evolution (LTE) modules, and millimeter-wave (mmWave) radar systems. Key findings indicate that RF exposure levels for RSUs and OBUs, as well as from Tesla’s integrated technologies, consistently remain below the International Commission on Non-Ionizing Radiation Protection (ICNIRP) exposure guidelines by a significant margin. Specifically, the maximum exposure level around RSUs was observed to be 10 times lower than ICNIRP reference level, and Tesla’s mmWave radar exposure did not exceed 0.29 W/m2, well below the threshold of 10 W/m2 set for the general public. This comprehensive analysis not only corroborates the effectiveness of numerical dosimetry in accurately predicting RF exposure but also underscores the compliance of current V2X communication technologies with exposure guidelines, thereby facilitating the protective advancement of intelligent transportation systems against potential health risks.
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The assessment of the out-of-plane response of unreinforced masonry (URM) buildings with cavity walls has been a popular topic in regions such as Central and Northern Europe, Australia, New Zealand, China and several other countries.Cavity walls are particularly vulnerable as the out-of-plane capacity of each individual leaf is significantly smaller than the one of a solid wall. In the Netherlands, cavity walls are characterized by an inner load-bearing leaf of calcium silicate bricks, and by an outer veneer of clay bricks that has only aesthetic and insulation functions. The two leaves are typically connected by means of metallic ties. This paper utilizes the results of an experimental campaign conducted by the authors to calibrate a hysteretic model that represents the axial cyclic response of cavity wall tie connections. The proposednumerical model uses zero-length elements implemented in OpenSees with the Pinching4 constitutive model to account for the compression-tension cyclic behaviour of the ties. The numerical model is able to capture important aspects of the tie response such as the strength degradation, the unloading stiffness degradation and the pinching behaviour. The numerical modelling approach in this paper can be easily adopted by practitioner engineers who aim to model the wall ties more accurately when assessing the structures against earthquakes.
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Analyzing historical decision-related data can help support actual operational decision-making processes. Decision mining can be employed for such analysis. This paper proposes the Decision Discovery Framework (DDF) designed to develop, adapt, or select a decision discovery algorithm by outlining specific guidelines for input data usage, classifier handling, and decision model representation. This framework incorporates the use of Decision Model and Notation (DMN) for enhanced comprehensibility and normalization to simplify decision tables. The framework’s efficacy was tested by adapting the C4.5 algorithm to the DM45 algorithm. The proposed adaptations include (1) the utilization of a decision log, (2) ensure an unpruned decision tree, (3) the generation DMN, and (4) normalize decision table. Future research can focus on supporting on practitioners in modeling decisions, ensuring their decision-making is compliant, and suggesting improvements to the modeled decisions. Another future research direction is to explore the ability to process unstructured data as input for the discovery of decisions.
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The drive to reduce the carbon intensity of the energy system has generated much interest in applying carbon-free fuels such as ammonia (NH3) in combustion systems. The high hydrogen density and well-established production processes make NH3 a valuable chemical energy carrier to address and sustain the energy shift toward renewable energy source integration. However, some difficulties can be highlighted in the NH3 practical application. The combustion of NH3 is prone to producing harmful nitric oxides. In addition, NH3 has lower reactivity than most hydrocarbon fuels, which makes ignition challenging. Also, admixing NH3 with highly reactive fuels such as DME will facilitate ignition. The partnerships of this proposal are very interested in applying renewable NH3 as fuel in combined heat and power engines, and this research proposal suggests simulating a dual-fuel engine with NH3 as its primary fuel. The results of this research will help determine the optimum operating conditions for performing an experimental study.
