NEMESYS: Enhanced Network Security for Seamless Service Provisioning in the Smart Mobile Ecosystem

As a consequence of the growing popularity of smart mobile devices, mobile malware is clearly on the rise, with attackers targeting valuable user information and exploiting vulnerabilities of the mobile ecosystems. With the emergence of large-scale mobile botnets, smartphones can also be used to launch attacks on mobile networks. The NEMESYS project will develop novel security technologies for seamless service provisioning in the smart mobile ecosystem, and improve mobile network security through better understanding of the threat landscape. NEMESYS will gather and analyze information about the nature of cyber-attacks targeting mobile users and the mobile network so that appropriate counter-measures can be taken. We will develop a data collection infrastructure that incorporates virtualized mobile honeypots and a honeyclient, to gather, detect and provide early warning of mobile attacks and better understand the modus operandi of cyber-criminals that target mobile devices. By correlating the extracted information with the known patterns of attacks from wireline networks, we will reveal and identify trends in the way that cyber-criminals launch attacks against mobile devices.Comment: Accepted for publication in Proceedings of the 28th International Symposium on Computer and Information Sciences (ISCIS'13); 9 pages; 1 figur

Corrosion behavior of new titanium alloy for biomedical applications

The biomedical field is in constant evolution and improvement, for such reason we’ve decided to search for a possible material to overcome the limitations of some of the most common biomaterials utilized, such as Titanium, known for its high biocompatibility and corrosion resistance and used for bone implants and bone fixation parts, or such as Zirconium, a material wuth good chemical stability and mechanical properties, with orthopedical and dental applications, our proposal is a material called R4, an alloy composed of Ti15Mo7Zr15TaSi, which we belive could one day overcome the previous materials in the biomedical field

Comparative study of Ti and Ti alloy for possible medical application

In the realm of modern medicine, the quest for innovation and improvement is relentless. One significant development that has transformed the landscape of medical devices and implants is the use of titanium and titanium alloys. Just as Titan stands as a resilient moon in the outer reaches of our cosmic neighborhood, titanium and its alloys have emerged as robust and versatile materials for a wide array of medical applications. From orthopedic implants to dental prosthetics, and even in cutting-edge biomedical engineering, titanium's exceptional combination of strength, biocompatibility, and corrosion resistance has made it an indispensable asset in modern medicine. Titanium and its alloys are not just elements on the periodic table; they are key elements in the quest for stronger, longer-lasting, and more effective medical treatments and devices

Influence of silicon addition on the properties of new titanium alloys

The mechanical characteristics and electrochemical behavior of the new titanium alloys TiMoZr, TiMoZrSi0.5, TiMoZrSi0.75 and TiMoZrSi1 were studied to determine their microstructure, corrosion behavior and mechanical properties. Following the use of the appropriate procedures, metallographic analysis showed that both samples had biphasic and dendritic structures. According to electrochemical tests in body simulation fluid, the samples' corrosion resistance increases with decreasing silicon content since silicon-containing samples corrode more quickly. Electrochemical Impedance Spectroscopy measurements were performed at various potentials, and the acquired spectra show a two-time constant system, due to the presence of a double-layer passive film on the samples. The three-point bending test for both samples demonstrated that the values of modulus of elasticity are lower than those commercial alloys and nearly to the cortical human bone, and the microhardness test showed that the samples' surfaces had soft and hard phases

Preliminary studies of new Ti alloys with different Mo content

This work aims to investigate the mechanical characteristics and biocompatibility of two novel titanium alloys, Ti15Mo7Zr15Ta1Si and Ti20Mo7Zr15Ta0,75Si.These samples have previously undergone cutting, grinding, polishing, and chipping. The studied samples were subjected to electrochemical, metallographic and corrosion behavior. Ti15Mo7Zr15Ta1Si and Ti20Mo7Zr15Ta0.75Si, the study samples, have demonstrated high corrosion potentials, lower corrosion rates, and consequently higher corrosion resistance. In summary, this study's data indicates that both alloys exhibit good corrosion behavior

Study of molybdenum stable oxide film in simulated body fluid

This study's main goal is to thoroughly compare the mechanical attributes and biocompatibility of the recently created titanium alloy Ti15Mo7Zr15Ta1Si (62% Ti, 15% Mo, 7% Zr, 15% Ta, 1% Si) to that of the pure metal Mo. The samples underwent a series of meticulous preparation procedures, including chip preparation, polishing, grinding, and cutting, to enable a thorough evaluation. These preparation steps were essential for ensuring the samples' consistency and uniformity, which allowed for accurate and reliable analyses of their mechanical and corrosionrelated properties. The samples' microstructure and surface morphology were also investigated using metallographic techniques, allowing a thorough examination of any potential flaws, grain boundaries, or phase compositions. Additionally, electrochemical tests were used to investigate the materials' corrosion resistance and electrochemical characteristics in environments that mimicked physiological conditions. The samples were subjected to a variety of electrochemical analyses, such as polarization curves and impedance spectroscopy, in order for the researchers to fully comprehend the corrosion behavior of the materials and their suitability for biomedical applications

New Titanium Alloys, Promising Materials for Medical Devices

Titanium alloys are used in medical devices due to their mechanical properties, but also for their corrosion resistance. The natural passivation of titanium-based biomaterials, on the surface of which a dense and coherent film of nanometric thickness is formed, composed mainly of TiO2, determines an apparent bioactivity of them. In this paper, the method of obtaining new Ti20MoxSi alloys (x = 0.0, 0.5, 0.75, and 1.0) is presented, their microstructure is analyzed, and their electrochemical responses in Ringer´s solution were systematically investigated by linear polarization, cyclic potential dynamic polarization, and electrochemical impedance spectroscopy (EIS). The alloys corrosion resistance is high, and no evidence of localized breakdown of the passive layer was observed. There is no regularity determined by the composition of the alloys, in terms of corrosion resistance, but it seems that the most resistant is Ti20Mo1.0Si

Effect of Heat Treatment on Some Titanium Alloys Used as Biomaterials

Titanium-based alloys are constantly improved to obtain properties suitable for their use. Improving titanium alloys is very important for performing alloys without side effects. In this paper effects of structure, microhardness, and indentation test of eight titanium alloys were investigated after aging. The heat treatment consisted of a high-temperature quenching accomplished in three steps (650 °C for 25 min, 850 °C for 20 min, and 950 °C for 20 min). The cooling process was accomplished using N2 gas, introduced in the chamber at a 9-bar pressure for 37 min. Then, followed by heating to a constant temperature tempering (550 °C) at 1.5 bar pressure and kept for 2 h and 10 min at 2 bar pressure. Optical microscopy images were obtained of Ti-Mo-Zr-Ta alloys with grain-specific aspects of titanium alloys; acicular and coarse structures are specific to β alloys. Microhardness results showed significantly influenced by the heat treatment, increased by approximately 5% for Ti15Mo7Zr15Ta1Si and Ti20Mo7Zr15Ta0.5Si, while for Ti15Mo7Zr15Ta0.5Si and Ti20Mo7Zr15Ta an approximately 9% decrease has been noted. The modulus of elasticity results obtained by the indentation method for the experimental alloys were between 36.25–66.24 GPa. The heat treatments applied to the alloys had a pronounced effect, improving both the structure of the alloys and the results of the indentation test

Microstructural Analysis and Tribological Behavior of Ti-Based Alloys with a Ceramic Layer Using the Thermal Spray Method

The present article focuses on a recently developed new system of alloys (Ti15MoSi) coated with ZrO2. The thin coatings deposition of ZrO2 on titanium alloys can be a solution to improve their corrosion resistance, biocompatibility, and to extend their long life with the human tissue. In order to improve the corrosion resistance, atmospheric plasma spraying coatings with zirconia have been performed. These coatings present a homogenous aspect with very few cracks. The novelty of the research is that zirconia is much stable in the simulated body fluids and presents no harm effects to the healing process of the bone. To analyze the thin coatings deposition, mechanical properties, chemical structure, and corrosion resistance were examined by a modulus of elasticity, X-ray diffraction (XRD), scanning electron microscopy-energy-dispersive X-ray spectroscopy (SEM-EDS), and linear polarization. The results reveal that Young’s modulus shows a low value (51 GPa for Ti15Mo0.5Si-ZrO2 and 48 GPa for Ti15Mo-ZrO2) and the XRD patterns show the presence of β-Ti and ZrO2 phases having a tetragonal crystalline structure. The research highlighted the morphological aspect of zirconia coatings on the new alloy titanium substrate, being an adherent compact coating with significantly improved corrosion resistance. Moreover, the mechanical properties are similar to the biological bone, which will avoid the stress shielding of the implant with bone tissue

IP security

This paper presents the network level security services currently available for the Internet infrastructure. Since IPsec is likely to become the largely accepted standard as far as IP level security is concerned, the paper describes the IPsec architecture including its defined security formats and the related key management procedures. Finally, common IPsec applications are presented and the future directions are outlined