4,562 research outputs found
Aye Win and Chit Moe (1 of 2)
No full textAye Win looking at her son, Chit Moe, while he translates from English to Karen
Aye Win with interviewers and translator
No full textA shot of Aye Win, Chit Moe, Meagan Gill, and Bethany Hanks as Chit Moe translated Meagan's words into Karen
Distributing quantum states with finite lifetime
No full textThis paper considers a quantum node tasked with the teleportation of multiple information-carrying qubit (ICQ) streams, each to a different receiver, by means of entanglements, local operations, and classical communi-cation. Our vision is that the node establishes entangled qubit pairs (EQPs) with the receivers before the arrival of ICQs, rather than waiting for their arrival. In this vein, the paper focuses on the class of protocols referred to as class I that instantaneously teleport arriving ICQs using preestablished EQPs, preventing arriving ICQs from decohering. The excess ratio epsilon r is introduced as a quantifier of the system resources per arriving ICQ, and epsilon r =1 is shown to be a critical threshold. With epsilon r > 1: for arrival streams characterized by interarrivals stochastically larger than exponential random variables, any member of class I teleports all arriving ICQs after a finite transient. With epsilon r < 1: for stationary ergodic arrival streams, there exists no protocol that teleports all arriving ICQs after a finite transient. This work thus establishes the ultimate limit for distributing quantum states with finite lifetime. Within class I, a protocol referred to as fresh information delivery (FID) is introduced and its optimality is proven. The operational characteristic of FID is provided in terms of the tradeoff between the waiting time of the EQP before it is utilized for teleportation and the excess ratio. Numerical experiments, comparing the proposed FID protocol with alternatives, corroborate the theoretical results. The results in this paper can be used for designing quantum nodes, paving the way for the implementation of the future quantum internet
Development of mesoscopic imaging system for surface inspection / Moe Win
No full textThe technology of mesoscopy brings into sight the microscopic level details of objects that are in dimensions of several meters, and the mesoscope is the device used for this purpose. The strength of this technology is that it can acquire ultrahigh-resolution images with micro to mesoscopic precision but with higher spatial resolution than a conventional microscope, and is able to solve the field of view limitations associated with optical microscopy. One of the main objectives of this is to develop and build a mesoscopic imaging system that can be used practically as an analytical tool for surface inspections. In particular, the focus is on the development of high-resolution images acquisition and advanced image processing algorithms which could be integrated with the surface inspection and diagnostic system. For this purpose, a high-resolution scanner consisting of a line CCD camera, lens, frame grabber and light source is used for acquiring high quality images of up to 5000 dpi (~5μm/pixel) with micro-mesoscopic spatial range. The post-processing system is mounted with image acquisition system, able to produce very sharp and high-resolution images. The high-resolution images of the samples are subjected to a manual inspection and automatic detection procedures. For the manual inspection, the images are processed and analyzed using raster graphics editors and the micro-meso scale defects are manually identified. The developed system is then utilised for inspection and defect detection of titanium coated surfaces, although appearing uniform, exhibits non-visible micro-cracks which remains hidden from naked eye observations. At high resolution range (above 600 dpi), non-uniformity and tiny defects could be easily detected by the developed mesoscopic imaging system. The results obtained are compared with those obtained from optical microscopy to verify the accuracy of detection. For the automatic inspection, defect detection algorithms based on image thresholding are developed and implemented as a statistical approach to identify possible defects. Existing thresholding-based and clustering-based methods are tested and compared to achieve faster and more efficient algorithms. Two new thresholding methods were developed. These are Contrast-Adjusted Otsu’s Method and Contrast-Adjusted Median-Based Otsu’s Method, which were then integrated into the automatic defect detection system. The proposed imaging system was shown to be capable of efficiently detecting microscopic surface features at any point of the scanned surface since the imaging system can provide ultra-high-resolution images. Also, as the design of the mesoscopic imaging system is built on line-scanning technology, measurements of colour fidelity and spatial accuracy is better than most other imaging systems. The significant findings of this research confirm that the proposed mesoscopic analytical imaging system is a novel approach in non-destructive measurement of surface coating quality
Passive radar via LTE signals of opportunity
No full textPassive radars relying on signals of opportunity enable new applications based on stealth tracking of targets without the need of radar signals emissions. Long term evolution (LTE) base stations employing orthogonal frequency division multiplexing (OFDM) signals are excellent candidates as illuminators of opportunity thanks to their wide availability. The tracking accuracy of such passive radars depends on prior knowledge (e.g., the wireless environment) and signal processing (e.g., clutter mitigation and tracking algorithm). This paper proposes passive radar systems exploiting LTE base stations as illuminators of opportunity to detect and track moving targets in a monitored environment. We analyze such systems based on a Bayesian framework for detection of moving targets and estimation of their position and velocity. A case study accounting for the LTE extended pedestrian model is presented, with various settings in terms of network configuration, wireless propagation, and signal processing
Photon-varied quantum states: Unified characterization
No full textThis paper introduces photon-varied quantum states (PVQSs), which generalize the nonclassical states obtained via photon addition or subtraction operations. We provide a unified characterization of PVQSs in terms of characteristic function, quasiprobability distribution, Fock representation, and Mandel Q parameter. In the special case of photon-varied Gaussian states (PVGSs), the characteristic functions and the quasiprobability distributions are found to be in a simple canonical product structure. Necessary and sufficient conditions for the negativity of the quasiprobability distributions are also obtained for PVGSs. The unified characterization enables the design and analysis of quantum systems that exploit the non-Gaussian properties of PVQSs
On the Design of Scheduling Algorithms for Wireless Navigation Networks
No full textNetwork navigation is a promising paradigm for providing accurate location-awareness in wireless environments, where mobile nodes estimate their locations based on inter- and intra-node measurements. In the presence of limited wireless resources, only a subset rather than all of the node pairs can perform inter-node measurements. Therefore, it is crucial to design efficient scheduling algorithms for selecting node pairs at different times for inter-node measurements. This paper develops a framework for the design of scheduling algorithms based on random access for network navigation. The proposed algorithms are suitable for practical operation of wireless navigation networks due to their distributed nature, and the optimized access probabilities of the agents lead to significant performance improvement
Unified Interference Engineering for Wireless Information Secrecy
No full textWireless communications are highly susceptible to eavesdropping due to their inherent broadcast nature. Recent works have proposed the use of interference for impeding the capabilities of the eavesdropping receivers in wireless networks. To fully unleash the potential of interference for wireless information secrecy, it is necessary to engineer network interference such that it impedes the capability of eavesdropping receivers while having mild effect on legitimate receivers. The task of generating network interference desirable for wireless secrecy is particularly challenging in heterogeneous networks due to their ample set of configurations. This paper proposes a unified interference engineering strategy (IES) for wireless information secrecy in heterogeneous networks. The unified IES combines zero forcing beamforming, artificial noise generation, cooperative jamming, and interference alignment to fully exploit the network's capability in wireless secrecy. The proposed strategy enables multiple nodes with heterogeneous capabilities to achieve mutually beneficial coordination, thereby leading to a new level of wireless information secrecy
Source Engineering for Quantum Key Distribution with Noisy Photon-Added Squeezed States
No full textQuantum key distribution (QKD) is a key enabler toward unconditionally secure communications. The imperfections exhibited by non-ideal sources degrade the QKD performance. This raises the problem of engineering the employed quantum states to mitigate the impairments caused by such imperfections. This paper proposes to employ noisy photon-added squeezed states (PASSs) as QKD sources for the decoy-state protocol. First, noisy PASSs are characterized in the Fock space. Then, noisy PASSs are engineered for the decoy-state protocol. Finally, the performance of the decoy-state protocol with engineered noisy PASSs are quantified in a variety of settings
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