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IOS firmware diversity, the unintended consequence of a complex firmware compilation process, has historically made reliable exploitation of Cisco routers difficult. With approximately 300,000 unique IOS images in existence, a new class of version‐agnostic shellcode is needed in order to make the large‐scale exploitation of Cisco IOS possible. The purpose of this paper is to show that such attacks are now feasible by demonstrating two different reliable shellcodes that will operate correctly over many Cisco hardware platforms and all known IOS versions.

The paper examines prior work in the area of Cisco IOS rootkits and constructs a novel IOS version‐agnostic rootkit called the interrupt‐hijack rootkit.

As the experimental results show, the techniques proposed in this paper can reliably inject command and control capabilities into arbitrary IOS images in a version‐agnostic manner.

The authors believe that the technique presented in this paper overcomes an important hurdle in the large‐scale, reliable rootkit execution within Cisco IOS. Thus, effective host‐based defence for such routers is imperative for maintaining the integrity of our global communication infrastructures.

Non-uniform rational B-splines (NURBSs) are the de facto standard for representing objects in computer-aided design (CAD). The purpose of this paper is to discuss how to stick to this standard in all phases of the additive manufacturing (AM) workflow, from the CAD object to the final G-code, bypassing unnecessary polygonal approximations.

The authors use a commercial CAD system (Rhino3D along with its programming environment Grasshopper) for direct slicing of the model, offset generation and trimming. Circular arcs are represented as quadratic NURBSs and free-form geometry as quadratic or cubic polynomial B-splines. Therefore, circular arcs are directly expressible as G2/G3 G-code commands, whereas free-form paths are rewritten as a succession of cubic Bézier curves, thereby admitting exact translation into G5 commands, available in firmware for AM controllers, such as Marlin.

Experimental results of this paper confirm a considerable improvement in quality over the standard AM workflow, consisting of an initial polygonization of the object (e.g. via standard tessellation language), slicing this polygonal approximation, offsetting the polygonal sections and, finally, generating G-code made up of polyline trajectories (G1 commands).

A streamlined AM workflow is obtained, with a seamless transfer from the initial CAD description to the final G-code. By adhering to the NURBS standard at all steps, the authors avoid multiple representations and associated errors resulting from approximations.

The purpose of this paper is to present the research efforts of the Center of Aeronautical Studies of the Federal University of Minas Gerais – Brazil to develop a low‐cost flight test data acquisition system for light aircraft and unmanned aerial vehicles (UAEs).

The development of this system was based on a microcontroller, chosen in accordance with main requirements of light aircrafts flight tests. The system uses the microcontroller in order to communicate with different kinds of sensors, including a GPS, and organize this information to be sent to a PDA device, which is used to control the acquisition process and storage the data acquired. Details about the development of this system, including firmware algorithm and sensors development, are presented and discussed in the paper.

The paper presents example results obtained with this system in applications such as performance evaluation and stability and control derivatives estimation problems. Take into account all the aspects of the system and the quality of the results, the main conclusion is that this system can efficiently support the demands of the aerospace industry for light aircraft and UAEs development programs as well as the necessities of the research centers and universities developing aeronautical research and didactic programs.

Recently, results confirm the applicability of this system in order to perform flight tests of aircrafts in accordance with FAR‐Part 23 or CS‐VLA or Light Sport Aircrafts as required by FAA Order 8130.2F and ASTM Designation F2245‐04.

This paper presents details about the construction of a low‐cost data acquisition system for flight tests of light aircrafts. The main advantage of this system is the use of a PDA device in order to control and storage the acquisition, which reduce costs, weight and size of the system and permits its installation in light aircrafts or UAVs.

This paper aims to present the mathematical foundation of so-called advance algorithms, developed to compensate for defects during acceleration and deacceleration of the print head in filament-based melt extrusion additive processes. It then investigates the validity of the mathematical foundation, its performance on a low-cost system and the effect of changing layer height on the algorithm’s associated process parameter.

This study starts with a compilation and review of literature associated with advance algorithms, then elaborates on its mathematical foundation and methods of implementation. Then an experiment displaying the performance of the algorithm implemented in Marlin machine firmware, Linear Advance 1.0, is performed using three different layer heights. The results are then compared with simulations of the system using Simulink.

Findings suggests that advance algorithms following the presented approach is capable of eliminating defects because of acceleration and deacceleration of the print head. The results indicate a layer height dependency on the associated process parameter, requiring higher compensation values for lower layer heights. It also shows higher compensation values for acceleration than deacceleration. Results from the simulated mathematical model correspond well with the experimental results but predict some rapid variations in flow rate that is not reflected in the experimental results.

As there are large variations in printer design and materials, deviation between different setups must be expected.

To the best of authors’ knowledge, this study is the first to describe and investigate advance algorithms in academic literature.

Digital voice assistants use wake word engines (WWEs) to monitor surrounding audio for detection of the voice assistant's name. There are two failed conditions for a WWE, false negative and false positive. Wake word false positives threaten a loss of personal privacy because, upon activation, the digital assistant records audio to the voice cloud service for processing.

This observational study attempted to identify which Amazon Alexa wake word and Amazon Echo smart speaker resulted in the fewest number of human voice false positives. During an eight-week period, false-positive data were collected from four different Amazon Echo smart speakers located in a small apartment with three female roommates.

Results from this study suggest the number of human voice false positives are related to wake word selection and Amazon Echo hardware. Results from this observational study determined that the wake word Alexa resulted in the fewest number of false positives.

This study suggests Amazon Alexa users can better protect their privacy by selecting Alexa as their wake word and selecting smart speakers with the highest number of microphones in the far-field array with 360-degree geometry.

The benefits associated with implementing concurrent engineering mean that more and more companies are looking to use it for their new product introduction process. Previously, methods for monitoring product development have included the use of metrics. “Predictive” metrics have also been used, but have mainly tended to focus on the software and firmware aspects of a product. Outlines metric ideas, but takes a holistic view of the product under development. Details an industrial case study which shows how information obtained during the product development process can be used to produce predictive metrics. These can be used as a means to make the development process more efficient. Discusses the benefits of predictive metrics and the impact that concurrent engineering approach has on the ability to provide these metrics.

In the context of the “year‐2000” problem, focuses on the risk involved in real time clocks and their interactions with associated embedded processors and logic arrays, dedicated electronic control and monitoring logic incorporated into larger systems. These are essential to the operation of a vast portfolio of infrastructures, from medical equipment, to buildings (phone, security, heating, plumbing and lighting), to transportation, to financial networks, to just‐in‐time delivery systems, and so on. According to a recent study, the firmware (permanently loaded instructions) that enables these systems to run is date sensitive and not year‐2000‐compliant in less than 1 percent of the 50 billion microprocessors and microcontrollers used in embedded systems installed worldwide by the end of the twentieth century. This small fraction will fail, causing the systems they control to begin failing around 1 January 2000 and for the first few years of the next century. Presents a pessimistic, illustrative scenario, describing the disruption of essential infrastructure from electric power, to food and fuel distribution, to communications, to financial networks.

The role of microcomputers and their applications in industrial robotics is illustrated. The special case of an intelligent robot is examined in detail. The design of a microcomputer to be used for automatic spatial ordering of objects is presented, and the experimental results are briefly exposed and critically evaluated.

The purpose of this paper is to describe a new multi‐sensor robotic system designed for riser, mooring lines and umbilical cables in situ underwater inspection. Due to the aggressive operation environment, such structures are susceptible to a broad spectrum of failure causes, such as aging, mechanical, chemical and thermal loads, hydrodynamic stresses, vortex‐induced vibrations and installation or fabrication non‐conformities. Current inspection methods present major risks and inefficiencies, especially as deeper fields are being reached for exploitation.

The SIRIS (In Situ Riser Inspection Robotic System) is designed to reconstruct the actual riser profile and perform non‐destructive tests. The robot is propelled by thrusters to scroll by the outside of the catenary riser. Mechanical, electronic hardware, image acquisition and software/firmware design are described here.

Simulated data from an inertial measurement unit is fused with depth sensor measurements, using a Kalman filter to reconstruct the riser profile, with small localization errors. Laboratory and sheltered waters tests were successfully executed to assess robot subsystems' performance: imaging, leakage, displacement and easiness of operation.

The robot prototype is designed to operate down to 250 m deep, although the final goal is reaching 3,000 m. Tests offshore, in a real oil production platform, have not been performed up to this moment. In the present version, the robot must be coupled to the riser with the aid of a scuba diver.

The robot is expected to allow non‐destructive testing in risers that cannot be performed nowadays with the existing tools. The inspecting procedure is easy to operate and does imply any kind of production stopping. More accurate assessment of the riser structural condition can allow extending its life span, thus avoiding early decommissioning.

Better assessment of actual riser facilities status will have great impact on reducing the chance of oil spill episodes and serious environment damage.

The design, construction and evaluation of a robotic tool for non‐destructive riser inspection has been described. A few similar robots exist in literature but none of them is able to reconstruct the actual riser profile.

This study aims to report the development of an open-source syringe extrusion head for shear-thinning materials. The target is to adapt open-source 3D printers to be helpful in research lines that use gels, hydrogels, pastes, inks, and bio-inks.

This hardware was designed to be compatible with a Graber i3-based 3D printer; nevertheless, it can be easily adapted to other open-source 3D printers.

The extrusion head successfully deposits the material during the 3D printing process. It was validated fabricating geometries that include scaffold structures, which are a possible application of bioprinting for tissue engineering. As reported, the extruded filaments allowed the porous samples' structuration.

This system expands the applications of open-source 3D printers used at the laboratory scale. It enables low-cost access to research areas such as tissue engineering and biofabrication, energy storage devices and food 3D printing.

The open-source hardware here reported is of simple fabrication, assembly and installation. It uses a Cardan coupling and a three guides system to transfer the stepper motor motion. This approach allows continuous movement transfer to the syringe piston, producing an adequate deposition or retraction. Thus, the effect of misalignments is avoided, considering that these latter can cause skipping steps in the motor, directly affecting the deposition.