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The purpose of this paper is to explain innocent actors in the virtual currency space (e.g. virtual currency exchanges, financial institutions, social media platforms) and how to avoid potential exposure because of the misconduct of users or customers.

Explains how pump-and-dump securities and commodities fraud schemes work, explains the Commodity Futures Trading Commission’s warning to consumers about how to avoid being victimized by schemers running pump-and-dump schemes in the virtual currency space, explains how innocent well-meaning actors may – because of misconduct by their customers or users – be at risk of exposure to victims of pump-and-dump schemes and provides practical guidance for avoiding these dangers and remediating problems.

Market participants must protect their reputations, and they cannot rely on the government to do so for them. Moreover, because investors who fall prey to fraud may be unable to recover from fraudsters, such investors may seek to recover from innocent market participants. Accordingly, market participants should take precautionary measures to avoid being used by fraudsters.

Practical guidance from experienced securities and financial services litigators.

To introduce blockchain in simple terms for business lawyers to be able to spot the right issues and ask the right questions.

This article provides an overview of blockchain, identifies two example use cases, and highlights some of the most pressing legal issues, including issues to address in on-chain programming, off-chain agreements and other issues when determining whether to implement a blockchain solution.

This article concludes that there has been a significant growth in investment and interest in blockchain. Numerous companies across different sectors have developed blockchain proof-of-concepts, with some heading towards production deployments. At this point, commercial blockchain is largely in the pilot or proof-of-concept stage across a wide range of use cases, with payments and supply chain being two of the most promising use cases. This article also identifies possible legal issues associated with blockchain.

Despite the growing interest in blockchain, it is still a novel topic to many business lawyers. It is very important that lawyers are able to identify the right issues and ask the right questions.

Practical guidance from experienced lawyers in the Technology Transactions and Financial Services Regulatory & Enforcement practices.

This study aims to comprehensively investigate the electron beam powder bed fusion (EB-PBF) process for copper, offering validated estimations of melt pool temperature and morphology through numerical and analytical approaches. This work also assesses how process parameters influence the temperature fluctuations and the morphological changes of the melt pool.

Two distinct methods, an analytical model and a numerical simulation, were used to assess temperature profiles, melt pool morphology and associated heat transfer mechanisms, including conduction and keyhole mode. The analytical model considers conduction as the dominant heat transfer mechanism; the numerical model also includes convection and radiation, incorporating specific parameters such as beam power, scan speed, thermophysical material properties and powder interactions.

Both the analytical model and numerical simulations are highly correlated. Results indicated that the analytical model, emphasising material conduction, exhibited exceptional precision, although at substantially reduced cost. Statistical analysis of numerical outcomes underscored the substantial impact of beam power and scan speed on melt pool morphology and temperature in EB-PBF of copper.

This numerical simulation of copper in EB-PBF is the first high-fidelity model to consider the interaction between powder and substrate comprehensively. It accurately captures material properties, powder size distribution, thermal dynamics (including heat transfer between powder and substrate), phase changes and fluid dynamics. The model also integrates advanced computational methods such as computational fluid dynamics and discrete element method. The proposed model and simulation offer a valuable predictive tool for melt pool temperature, heat transfer processes and morphology. These insights are critical for ensuring the bonding quality of subsequent layers and, consequently, influencing the overall quality of the printed parts.

This paper aims to present the results of a study on the behaviour of cold-formed galvanized steel beams subjected to fire, using the results of a large programme of experimental tests.

The research investigated the influence of web stiffeners in the sections and the stiffness of the surrounding structure, including the axial and rotational restraining to the thermal elongation, on the flexural behaviour of the beams in case of fire. In other words, the structural response of different open cold-formed steel beams, with and without web stiffeners, was compared in case of fire.

The results showed that a good choice between using cold-formed steel beams, with and without web stiffeners, may depend on the section shape and the internal forces generated in these members during a fire.

Temperatures in the furnace and at several points of the beams, as well as deformations and restraining forces and moments, were measured to achieve those goals and consequently to assess the critical time and temperature of these beams.

This research paper adopts the fundamental tenets of advanced technologies in industry 4.0 to monitor the structural health of concrete beam members using cost-effective non-destructive technologies. In so doing, the work illustrates how a coalescence of low-cost digital technologies can seamlessly integrate to solve practical construction problems.

A mixed philosophies epistemological design is adopted to implement the empirical quantitative analysis of “real-time” data collected via sensor-based technologies streamed through a Raspberry Pi and uploaded onto a cloud-based system. Data was analysed using a hybrid approach that combined both vibration-characteristic-based method and linear variable differential transducers (LVDT).

The research utilises a novel digital research approach for accurately detecting and recording the localisation of structural cracks in concrete beams. This non-destructive low-cost approach was shown to perform with a high degree of accuracy and precision, as verified by the LVDT measurements. This research is testament to the fact that as technological advancements progress at an exponential rate, the cost of implementation continues to reduce to produce higher-accuracy “mass-market” solutions for industry practitioners.

Accurate structural health monitoring of concrete structures necessitates expensive equipment, complex signal processing and skilled operator. The concrete industry is in dire need of a simple but reliable technique that can reduce the testing time, cost and complexity of maintenance of structures. This was the first experiment of its kind that seeks to develop an unconventional approach to solve the maintenance problem associated with concrete structures. This study merges industry 4.0 digital technologies with a novel low-cost and automated hybrid analysis for real-time structural health monitoring of concrete beams by fusing several multidisciplinary approaches into one integral technological configuration.

Road passenger transportation faces a global challenge of reducing environmental pollution and greenhouse gas emissions because of the vehicle weight increases needed to enhance passenger safety and comfort. This paper aims to present a preliminary mechanical design evaluation of the Wikispeed Car (with a focus on body bending, body torsion and body crash) to assess light-weighting implications and improve the vehicle’s environmental performance without compromising safety.

For this research, finite element analysis (FEA) was performed to examine the Wikispeed chassis for light-weighting opportunities in three key aspects of the vehicle’s design, namely, for body bending the rockers (or longitudinal tubes), for body torsion (again on the rockers but also the chassis as a whole) and for crash safety – on the frontal crash structure. A two-phase approach was adopted, namely, in phase one, a 3D CAD geometry was generated and in phase, two FEA was generated. The combination of analysis results was used to develop the virtual model using FEA tools, and the model was updated based on the correlation process.

The research revealed that changing the specified material Aluminium Alloy 6061-T651 to Magnesium EN-MB10020 allows vehicle mass to be reduced by an estimated 110 kg, thus producing a concomitant 10 per cent improvement in fuel economy. The initial results imply that the current beam design made from magnesium would perform worst during a crash as the force required to buckle the beam is the lowest (between 95.2 kN and 134 kN). Steel has the largest bandwidth of force required for buckling and also requires the largest force for buckling (between 317 kN and 540 kN).

This is the first study of its kind to compare and contrast between material substitution and its impact upon Wikispeed car safety and performance.

This paper presents the experimental and numerical results of the bending properties of low-height prestressed T-beams. The purpose is to study the bearing capacity, failure state and strain distribution of low-height prestressed T-beams.

First, two 13 m-long full-size test beams were fabricated with different positions of prestressed steel bundles in the span. The load–deflection curves and failure patterns of each test beam were obtained through static load tests. Secondly, the test data were used to validate the finite element model developed to simulate the flexural behavior of low-height prestressed T-beams. Finally, the influence of different parameters (the number of prestressed steel bundles, initial prestress and concrete strength grade) on the flexural performance of the test beams is studied by using a finite element model.

The test results show that when the distance of the prestressed steel beam from the bottom height of the test beam increases from 40 to 120 mm, the cracking load of the test beam decreases from 550.00 to 450.00 kN, reducing by 18.18%, and the ultimate load decreases from 1338.15 to 1227.66 kN, reducing by 8.26%, therefore, the increase of the height of the prestressed steel beam reduces the bearing capacity of the test beam. The numerical simulation results show that when the number of steel bundles increases from 2 to 9, the cracking load increases by 183.60%, the yield load increases by 117.71% and the ultimate load increases by 132.95%. Therefore, the increase in the number of prestressed steel bundles can increase the cracking load, yield load and ultimate load of the test beam. When the initial prestress is from 695 to 1,395 MPa, the cracking load increases by 69.20%, the yield load of the bottom reinforcement increases by 31.61% and the ultimate load increases by 3.97%. Therefore, increasing the initial prestress can increase the cracking load and yield load of the test beam, but it has little effect on the ultimate load. The strength grade of concrete increases from C30 to C80, the cracking load is about 455.00 kN, the yield load is about 850.00 kN and the ultimate load is increased by 4.90%. Therefore, the improvement in concrete strength grade has little influence on the bearing capacity of the test beam.

Based on the experimental study, the bearing capacity of low-height prestressed T-beams with different prestressed steel beam heights is calculated by finite element simulation, and the influence of different parameters on the bearing capacity is discussed. This method not only ensures the accuracy of bearing capacity assessment, but also does not require a large number of samples and has a certain economy. The study of prestressed low-height T-beams is of great significance for understanding the principle and application of prestressed technology. Research on the mechanical behavior and performance of low-height prestressed T beams can provide a scientific basis and technical support for the design and construction of prestressed concrete structures. In addition, the study of prestressed low-height T-beams can also provide a reference for the optimization design and construction of other structural types.

This paper aims to facilitate verification of computer modelling techniques for complex structures exposed to fire and to test the effect of some steel beams being left unprotected.

This paper describes a fire test conducted on a large-scale structure representing four corner bays of a typical multi-storey steel-frame office building.

A new and unexpected mode of damage occurred.

The test results indicate that an alternate reinforcement detail should be used in combination with unprotected beams.

This paper aims to present a three-dimensional (3D) model of hybrid laser welding of a steel plate. Before welding, the plate is pre- and/or post-heated by induction to avoid mechanical stresses in material due to high gradients of temperature. Welding itself is realized by laser beam without welding rod. The model takes into account existence of both solid and liquid phases in the weld.

Presented is the complete mathematical model of the above heat treatment process, taking into account all relevant nonlinearities (saturation curve of the processed steel material and temperature dependences of its physical parameters). Its numerical solution is realized by the finite element method. Some important results are compared with experimental data.

In comparison with the former model developed by the authors that did not take into account the phase change, the results are more realistic and exhibit a better accordance with measurements. On the other hand, they strongly depend on sufficiently accurate knowledge of material parameters in both solid and liquid levels (that represent the input data).

The quality of calculated results strongly depends on the material properties and their temperature dependencies. In case of alloys (whose chemical composition may vary in some range), such data are often unavailable and must be estimated on the basis of experiments. Another quantity that has to be calibrated is the time dependence of power delivered by the laser beam, which is due to the production of a plasma cloud above the exposed spot.

The presented model and methodology of its solution may represent a basis for design of the complete technology of laser welding with induction pre-heating and/or post-heating.

Fully 3D model of hybrid laser welding (supplemented with pre- and/or post-heating by magnetic induction) taking into account both solid and liquid phases of welded metal and influence of the plasma cloud is presented.