Constraint Refinement for Online Verifiable Cross-Layer System Adaptation

A radio asset the executive's system is displayed for the IEEE 802.16-based OFDM/MIMO remote femtocell systems. The real segments of the system, specifically, subchannel assignment, affirmation control, and course choice plans are grown with the goal that the nature of administration (QoS) can be ensured on a for each association premise. The meaning of the up and coming age of remote femtocell correspondences is at present in progress. Among numerous specialized choices, one that is especially central is the decision of the physical layer adjustment arrangement and waveform, an issue for which a few choices have been proposed. Two of the most encouraging applicants are: 1) symmetrical recurrence division numerous (OFDM), a preservationist suggestion that expands upon the tremendous inheritance of 4G systems and 2) channel bank multicarrier/balance quadrature sufficiency balance (FBMC/OQAM), a dynamic methodology that in recurrence particular channels penances subcarrier symmetry rather than expanded unearthly proficiency. The near benefits of OFDM and FBMC/OQAM have been all around examined in the course of the most recent couple of years however for the most part, from a simple physical layer perspective and generally dismissing how the physical layer execution converts into client applicable measurements at the upper-layers. This work targets showing an extensive correlation of both adjustment designs as far as reasonable system markers, for example, good put, deferral, reasonableness, and service coverage, and under operational conditions that can be imagined to be sensible in 5G arrangements. To this the end, a bringing together cross-layer system is suggested that envelops the downlink planning and asset assignment methods and that expands upon a model of the lining procedure at the information connection control layer and a physical layer the reflection that can be picked to demonstrate either OFDM or FBMC/OQAM

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Cross-layer System Designs for Scalable Video Streaming over Mobile WiMAX

2007 IEEE Wireless Communications and Networking Conference ◽

10.1109/wcnc.2007.349 ◽

2007 ◽

Cited By ~ 11

Author(s):

Hung-Hui Juan ◽

Hsiang-Chun Huang ◽

ChingYao Huang ◽

Tihao Chiang

Keyword(s):

Video Streaming ◽

Scalable Video ◽

Mobile Wimax ◽

Cross Layer ◽

Layer System ◽

System Designs ◽

Scalable Video Streaming

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WiMAX Cross-Layer System for Next Generation Heterogeneous Environments

WIMAX New Developments ◽

10.5772/8277 ◽

2009 ◽

Cited By ~ 2

Author(s):

Pedro Neves ◽

Susana Sargento ◽

Kostas Pentikousis ◽

Francisco Fontes

Keyword(s):

Cross Layer ◽

Heterogeneous Environments ◽

Next Generation ◽

Layer System

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Cross-Layer Adaptation with Safety-Assured Proactive Task Job Skipping

ACM Transactions on Embedded Computing Systems ◽

10.1145/3477031 ◽

2021 ◽

Vol 20 (5s) ◽

pp. 1-25

Author(s):

Zhilu Wang ◽

Chao Huang ◽

Hyoseung Kim ◽

Wenchao Li ◽

Qi Zhu

Keyword(s):

Resource Constraints ◽

Dynamic Environment ◽

Schedulability Analysis ◽

Cross Layer ◽

Critical Systems ◽

Adaptation Algorithm ◽

Functional Layer ◽

Runtime Adaptation ◽

System Adaptation ◽

And Control

During the operation of many real-time safety-critical systems, there are often strong needs for adapting to a dynamic environment or evolving mission objectives, e.g., increasing sampling and control frequencies of some functions to improve their performance under certain situations. However, a system's ability to adapt is often limited by tight resource constraints and rigid periodic execution requirements. In this work, we present a cross-layer approach to improve system adaptability by allowing proactive skipping of task executions, so that the resources can be either saved directly or re-allocated to other tasks for their performance improvement. Our approach includes three novel elements: (1) formal methods for deriving the feasible skipping choices of control tasks with safety guarantees at the functional layer, (2) a schedulability analysis method for assessing system feasibility at the architectural layer under allowed task job skippings, and (3) a runtime adaptation algorithm that efficiently explores job skipping choices and task priorities for meeting system adaptation requirements while ensuring system safety and timing correctness. Experiments demonstrate the effectiveness of our approach in meeting system adaptation needs.

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The Formation of Nonzonal Jets over Sloped Topography

Journal of Physical Oceanography ◽

10.1175/jpo-d-11-0152.1 ◽

2012 ◽

Vol 42 (10) ◽

pp. 1635-1651 ◽

Cited By ~ 16

Author(s):

Emma J. D. Boland ◽

Andrew F. Thompson ◽

Emily Shuckburgh ◽

Peter H. Haynes

Keyword(s):

Large Scale ◽

Lower Layer ◽

Effective Diffusivity ◽

Cross Layer ◽

Dynamical Response ◽

Layer System ◽

Topographic Slope ◽

Transport Barriers ◽

Insight Into ◽

Pv Gradient

Abstract Coherent jets are ubiquitous features of the ocean’s circulation, and their characteristics, such as orientation and energetics, may be influenced by topography. In this study, the authors introduce a large-scale, topographic slope with an arbitrary orientation into quasigeostrophic, doubly periodic, barotropic and baroclinic systems. In both systems, the flow organizes itself into coherent tilted nonzonal jets that are aligned perpendicular to the barotropic potential vorticity (PV) gradient. In the two-layer system, the upper layer, the lower layer, and the barotropic PV gradients all have different orientations and therefore the jets cross the layer-wise PV gradients. The fact that the jets cross layer-wise PV gradients and the requirement of conservation of PV for fluid parcels together results in the drift of the tilted jets across the domain. Like their zonal counterparts, the tilted jets exhibit strong transport anisotropy. The dynamical response to jet deflection is very strong in the two-layer baroclinic case, with eddy energy production increasing by orders of magnitude as the topographic slope becomes more zonal. This increase in eddy energy is also reflected in an increase in jet spacing and a reduction in strength of the across-jet transport barriers, shown using an effective diffusivity diagnostic. The dynamics identified here, while formally valid within the constraints of quasigeostrophic scalings, provide important insight into the sensitive relationship between flow orientation and flow stability in regions with broad topographic slopes.

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