Computation Offloading Algorithms in Mobile Edge Computing System: A Survey

With the rapid development of the internet of things (IoT), the number of devices that can connect to the network has exploded. More computation intensive task appear on mobile terminals, and mobile edge computing has emerged. Computation offloading technology is a key technology in mobile edge computing. This survey reviews the state of the art of computation offloading algorithms. It was classified into three categories: computation offloading algorithms in MEC system with single user, computation offloading algorithms in MEC system with multiple users, computation offloading algorithms in MEC system with enhanced MEC server. For each category of algorithms, the advantages and disadvantages were elaborated, some challenges and unsolved problems were pointed out, and the research prospects were forecasted.

Hybrid magnetic resonance and optoacoustic tomography(MROT) for preclinical neuroimaging

Multi-modal imaging is essential for advancing our understanding of brain function and unraveling pathophysiological processes underlying neurological and psychiatric disorders.Magnetic resonance(MR)and optoacoustic(OA)imaging have been shown to provide highly complementary contrasts and capabilities for preclinical neuroimaging.True integration between these modalities can thus offer unprecedented capabilities for studying the rodent brain in action.We report on a hybrid magnetic resonance and optoacoustic tomography(MROT)system for concurrent noninvasive structural and functional imaging of the mouse brain.Volumetric OA tomography was designed as an insert into a high-field MR scanner by integrating a customized MR-compatible spherical transducer array,an illumination module,and a dedicated radiofrequency coil.A tailored data processing pipeline has been developed to mitigate signal crosstalk and accurately register image volumes acquired with T1-weighted,angiography,and blood oxygenation level-dependent(BOLD)sequences onto the corresponding vascular and oxygenation data recorded with the OA modality.We demonstrate the concurrent acquisition of dual-mode anatomical and angiographic brain images with the scanner,as well as real-time functional readings of multiple hemodynamic parameters from animals subjected to oxygenation stress.Our approach combines the functional and molecular imaging advantages of OA with the superb soft-tissue contrast of MR,further providing an excellent platform for cross-validation of functional readings by the two modalities.

Multifocal structured illumination optoacoustic microscopy

Optoacoustic(OA)imaging has the capacity to effectively bridge the gap between macroscopic and microscopic realms in biological imaging.High-resolution OA microscopy has so far been performed via point-by-point scanning with a focused laser beam,thus greatly restricting the achievable imaging speed and/or field of view.Herein we introduce multifocal structured illumination OA microscopy(MSIOAM)that attains real-time 3D imaging speeds.For this purpose,the excitation laser beam is shaped to a grid of focused spots at the tissue surface by means of a beamsplitting diffraction grating and a condenser and is then scanned with an acousto-optic deflector operating at kHz rates.In both phantom and in vivo mouse experiments,a 10mm wide volumetric field of view was imaged with 15 Hz frame rate at 28μm spatial resolution.The proposed method is expected to greatly aid in biological investigations of dynamic functional,kinetic,and metabolic processes across multiple scales.