A trust supportive framework for pervasive computing systems

Recent years have witnessed the emergence and rapid growth of pervasive comput- ing technologies such as mobile ad hoc networks, radio frequency identification (RFID), Wi-Fi etc. Many researches are proposed to provide services while hiding the comput- ing systems into the background environment. Trust is of critical importance to protect service integrity & availability as well as user privacies. In our research, we design a trust- supportive framework for heterogeneous pervasive devices to collaborate with high security confidence while vanishing the details to the background. We design the overall system ar- chitecture and investigate its components and their relations, then we jump into details of the critical components such as authentication and/or identification and trust management. With our trust-supportive framework, the pervasive computing system can have low-cost, privacy-friendly and secure environment for its vast amount of services

Mid-Infrared HgTe Colloidal Quantum Dots In-Situ Passivated by Iodide

Today, colloidal quantum dots (CQDs) have received wide attention due to their properties of tunable infrared absorption. For example, HgTe colloidal quantum dots have shown excellent optical absorption (absorption coefficient α > 104 cm−1), spectral absorption tunability covering the entire infrared atmospheric window, and even the terahertz (THz). However, the efficient surface passivation of HgTe CQDs was limited by the highly sterically hindered long-chain organic ligands. Here, we demonstrate a new method to synthesize monodisperse mid-infrared HgTe CQDs, and the preparation process of the Hg precursor solution is optimized. With I− in-situ passivated on the surfaces, the spherical HgTe quantum dots are successfully synthesized with the tunability size from 8 to 15 nm. The noise current density of the photoconductive device is as low as 10−11 A·Hz−1/2 at 130 K with a frequency of 1 Hz