P2P computing for intelligence of things

Peer-to-Peer Networking and Applications -     

The Intensity and Externality Effects of Information Technology Investments on National Productivity Growth

This study investigates the relation between information technology (IT) expenditures and national productivity based on a production estimation approach by using a pooled time-series country-level data set for the period from 1992 to 2000. The results, which confirm the findings of earlier studies on country-level IT investment effect, show IT has significant and positive effects on national productivity growth. We find that IT intensity improves the positive effect of IT investment on national productivity growth and that the existence of IT externalities, through which spillovers of knowledge and innovation occur, may eventually lead to long-run persistent national productivity growth.     

The Trade-Off Between Performance and Security of Virtualized Trusted Execution Environment on Android

Nowadays, with the significant growth of the mobile market, security issues on the Android Operation System have also become an urgent matter. Trusted execution environment (TEE) technologies are considered an option for satisfying the inviolable property by taking advantage of hardware security. However, for Android, TEE technologies still contain restrictions and limitations. The first issue is that non-original equipment manufacturer developers have limited access to the functionality of hardware-based TEE. Another issue of hardware-based TEE is the cross-platform problem. Since every mobile device supports different TEE vendors, it becomes an obstacle for developers to migrate their trusted applications to other Android devices. A software-based TEE solution is a potential approach that allows developers to customize, package and deliver the product efficiently. Motivated by that idea, this paper introduces a VTEE model, a software-based TEE solution, on Android devices. This research contributes to the analysis of the feasibility of using a virtualized TEE on Android devices by considering two metrics: computing performance and security. The experiment shows that the VTEE model can host other software-based TEE services and deliver various cryptography TEE functions on the Android environment. The security evaluation shows that adding the VTEE model to the existing Android does not add more security issues to the traditional design. Overall, this paper shows applicable solutions to adjust the balance between computing performance and security.     

Predicting the performance and NOx emissions of a turbocharged spark-ignition engine generator fueled with biogases and hydrogen addition under down-boosting condition

The characteristics of an engine generator fueled with methane-based biogas and its blend with hydrogen (H₂) were numerically investigated using a one-dimensional cycle simulation and the fractional factorial design of experiment method. Based on the experimental results, the numerical model was validated and calibrated under various excess air ratio (EAR), boost pressure, spark timing, and biogas composition conditions. The conventional and current optimization methods, maximum brake torque (MBT), and minimum input fuel (MIF) conditions, were compared in terms of engine performance, NO_x emission, and generating efficiency. Under MBT conditions, although higher torque and mass fraction burned (MFB) could be achieved, boosting degradation was evident at the optimum MBT timing. On the contrary, under MIF conditions with down-boosting, reduced NO_x formation and improved generating efficiency could be achieved, but was accompanied by an MFB decrease. Moreover, the reduced MFB could be enhanced by H₂ addition and spark-timing control. Compared to MBT, MIF optimization had advantages in terms of generating efficiency, NO_x emission reduction, and spark-timing control, and could avoid boosting degradation over the entire operating range for various fuel compositions.     

Distributed hybrid P2P networking systems

Peer-to-Peer Networking and Applications -     

ASL Recognition by the Layered Learning Model Using Clustered Groups

American Sign Language (ASL) images can be used as a communication tool by determining numbers and letters using the shape of the fingers. Particularly, ASL can have an key role in communication for hearing-impaired persons and conveying information to other persons, because sign language is their only channel of expression. Representative ASL recognition methods primarily adopt images, sensors, and pose-based recognition techniques, and employ various gestures together with hand-shapes. This study briefly reviews these attempts at ASL recognition and provides an improved ASL classification model that attempts to develop a deep learning method with meta-layers. In the proposed model, the collected ASL images were clustered based on similarities in shape, and clustered group classification was first performed, followed by reclassification within the group. The experiments were conducted with various groups using different learning layers to improve the accuracy of individual image recognition. After selecting the optimized group, we proposed a meta-layered learning model with the highest recognition rate using a deep learning method of image processing. The proposed model exhibited an improved performance compared with the general classification model.     

Molecular dynamics simulation study of the growth of a rough amorphous carbon film by the grazing incidence of energetic carbon atoms

The morphological evolution of an amorphous carbon film deposited by energetic carbon atoms of 75 eV with various angles of incidence was investigated by molecular dynamics simulation. Normal or near-normal incidence of carbon atoms resulted in a smooth surface of the deposited film. In contrast, a bump-like surface structure emerged and led to rough surfaces at grazing incidences, in agreement with the experiments. The bifurcated growth mode was explained by the impact-induced transport of atoms on the growing surface. The downhill transport of atoms on a sloping surface dominates at normal incidence, which suppresses the evolution of surface irregularities to form a rough surface. However, the dominance of uphill transport at a grazing incidence made the surface irregularities grow to a seed structure, which provided the shadowing effect during carbon deposition. This mechanism mediates initial seed formation and subsequent roughening together with shadowing effects under grazing incidence.     

A 300-GHz CMOS 7-by-7 Detector Array for Optics-less THz Imaging with Scan-less Target Object

Journal of Infrared, Millimeter, and Terahertz Waves - In this work, a 300-GHz 7?×?7 detector array based on a 65-nm Si CMOS technology has been developed and transmission imaging...     

PLGA Spherical Nucleic Acids

A new class of polymer spherical nucleic acid (SNA) conjugates comprised of poly(lactic‐co‐glycolic acid) (PLGA) nanoparticle (NP) cores is reported. The nucleic acid shell that defines the PLGA‐SNA exhibits a half‐life of more than 2 h in fetal bovine serum. Importantly, the PLGA‐SNAs can be utilized to encapsulate a hydrophobic model drug, coumarin 6, which can then be released in a polymer composition‐dependent tunable manner, while the dissociation rate of the nucleic acid shell remains relatively constant, regardless of core composition. Like prototypical gold NP conjugate SNAs, PLGA‐SNAs freely enter Raw‐Blue cells and can be used to activate toll‐like receptor 9 in a sequence‐ and dose‐dependent manner. Taken together, the data show that this novel nanoconstruct provides a means for controlling the release kinetics of encapsulated cargos in the context of the SNA platform, which may be useful for developing combination therapeutics.