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  1. With the evolution of 5G and Internet of Things technologies, Mobile Edge Computing (MEC) has emerged as a major computing paradigm. Compared to cloud computing, MEC integrates network control, computing, and storage to customizable, fast, reliable, and secure distributed services that are closer to the user and data site. Although a popular research topic, MEC resource management comes in many forms due to its emerging nature and there exists little consensus in the community. In this survey, we present a comprehensive review of existing research problems and relevant solutions within MEC resource management. We first describe the major problems in MEC resource allocation when the user applications have diverse performance requirements. We discuss the unique challenges caused by the dynamic nature of the environments and use cases where MEC is adopted. We also explore and categorize existing solutions that address such challenges. We particularly explore traditional optimization-based methods and deep learning-based approaches. In addition, we take a deeper dive into the most popular applications and use cases that adopt MEC paradigm and how MEC provides customized solutions for each use cases, in particular, video analytics applications. Finally, we outline the open research challenges and future directions. 1 
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    Free, publicly-accessible full text available December 31, 2024
  2. Abstract

    Image processing plays a vital role in artificial visual systems, which have diverse applications in areas such as biomedical imaging and machine vision. In particular, optical analog image processing is of great interest because of its parallel processing capability and low power consumption. Here, we present ultra-compact metasurfaces performing all-optical geometric image transformations, which are essential for image processing to correct image distortions, create special image effects, and morph one image into another. We show that our metasurfaces can realize binary image transformations by modifying the spatial relationship between pixels and converting binary images from Cartesian to log-polar coordinates with unparalleled advantages for scale- and rotation-invariant image preprocessing. Furthermore, we extend our approach to grayscale image transformations and convert an image with Gaussian intensity profile into another image with flat-top intensity profile. Our technique will potentially unlock new opportunities for various applications such as target tracking and laser manufacturing.

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  3. null (Ed.)
  4. Abstract

    Room temperature stable excitons in layered two‐dimensional (2D) transition metal dichalcogenides (TMDs) offer a unique route for engineering light and matter interactions. Due to the strong optical dispersion near the excitonic transitions, a high refractive index arises in these ultrathin semiconductors.[1,2]Utilizing this behavior, strongly confined Fano type optical resonances in an ultrathin (i.e., ≈12 nm) tungsten disulfide (WS2) photonic crystal (PhC) directly fabricated on a TMD‐on‐glass platform are reported. In this approach, Fano‐type WS2photonic resonances strongly couple to the WS2excitonic dispersion engender self‐resonant exciton‐polaritons with an out‐of‐plane optical confinement exceeding that provided by surface plasmon polaritons in the visible. The large spatial light‐matter overlap endowed by this unique monolithic self‐coupling scheme is utilized for steering of enhanced 2D WSe2excitonic photoluminescence in a truly TMD integrated system. It is envisioned that the strong light matter interaction on the TMD‐on‐glass platform will unfold the prospects of ultrathin exciton‐polaritonic resonators.

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