arXiv subjects

Yun Zhou

Publications and source records attributed to Yun Zhou.

59 records · Page 4Linked to original sources

arXiv2015

Because we care: Privacy Dashboard on Firefox OS

In this paper we present the Privacy Dashboard -- a tool designed to inform and empower the people using mobile devices, by introducing features such as Remote Privacy Protection, Backup, Adjustable Location Accuracy, Permission Control and Secondary-User Mode. We have implemented our solution on FirefoxOS and conducted user studies to verify the usefulness and usability of our tool. The paper starts with a discussion of different aspects of mobile privacy, how users perceive it and how much they are willing to give up for better usability. Then we describe the tool in detail, presenting what incentives drove us to certain design decisions. During our studies we tried to understand how users interact with the system and what are their priorities. We have verified our hypothesis, and the impact of the educational aspects on the decisions about the privacy settings. We show that by taking a user-centric development of privacy extensions we can reduce the gap between protection and usability.

cs.CR↗

arXiv2015

Spectroscopic super-resolution fluorescence cell imaging using ultra-small Ge quantum dots

In single molecule localisation super-resolution microscopy the need for repeated image capture limits the imaging speed, while the size of fluorescence probes limits the possible theoretical localisation resolution. Here, we demonstrated a spectral imaging based super-resolution approach by separating the overlapping diffraction spots into several detectors during a single scanning period and taking advantage of the size-dependent emission wavelength in nanoparticles. This approach has been tested using off-the-shelf quantum dots (Qdot) and in-house novel ultra-small (~3 nm) Ge QDs. Furthermore, we developed a method-specific Gaussian fitting and maximum likelihood estimation based on a Matlab algorithm for fast QDs localisation. We demonstrate that this methodology results in ~ 40 nm localisation resolution using commercial QDs and ~12 nm localisation resolution using Ge QDs. Using a standard scanning confocal microscope we achieved data acquisition rate of 1.6 seconds/frame. However, we show that this approach has a potential to deliver data acquisition rates on ms scale thus providing super-resolution in live systems.

physics.optics↗

arXiv2010

Minimal model of a heat engine: An information theory approach

We construct a generic model for a heat engine using information theory concepts, attributing irreversible energy dissipation to the information transmission channels. Using several forms for the channel capacity, classical and quantum, we demonstrate that our model recovers both the Carnot principle in the reversible limit, and the universal maximum power efficiency expression of nonreversible thermodynamics in the linear response regime. We expect the model to be immensely useful as a testbed for studying fundamental topics in thermodynamics.

cond-mat.stat-mech↗

arXiv2006

Magnetoresistance in Thin Permalloy Film (10nm-thick and 30-200nm-wide) Nanocontacts Fabricated by e-Beam Lithography

In this paper we show spin dependent transport experiments in nanoconstrictions ranging from 30 to 200nm. These nanoconstrictions were fabricated combining electron beam lithography and thin film deposition techniques. Two types of geometries have been fabricated and investigated. We compare the experimental results with the theoretical estimation of the electrical resistance. Finally we show that the magnetoresistance for the different geometries does not scale with the resistance of the structure and obtain drops in voltage of 20mV at 20Oe.

cond-mat.mtrl-sci↗

arXiv2003

Modeling SARS Spreading on Complex Networks

The spreading of SARS will destruct the initial network structure to a new phase, and in turn the spreading process will be weakened effectively and finally halted by this evolution of network structure. This mechanism is called immunity of contact network in this paper. What we can do is to accelerate effectively this process only.

cond-mat.stat-mech↗