A proactive approach for runtime self-adaptation based on queueing network fluid analysis

AbstractThis brief includes a summary of the Ph.D. thesis entitled “Traffic management in networks with programmable data planes” and supervised by Prof. Antonio Capone. Software-Defined Networking (SDN) enables the configuration and operation of communications networks through open software programming interfaces providing an unprecedented flexibility in their dynamic reconfiguration and management. The thesis analyses the opportunities for traffic management provided by the SDN paradigm at different levels. Starting from the programmability at the control plane, we have designed a Traffic Engineering framework operating on the global view offered on top of the controller to proactively configure the network according to traffic measurements while limiting the number of reconfigurations. In order to deal with unexpected conditions such as network failures and congestion, the above centralized, global and proactive approach has been complemented by reactive and distributed approaches based on advanced stateful programmable data planes which enable a self-adaptation according to partial local information yielding to a more prompt and scalable reaction. All the solutions presented in the thesis have been evaluated with software prototypes based on research-oriented or production-ready open-source tools. Some of the extensions developed for these tools have been integrated as official open-source contributions.

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A queueing network model of task prioritization using a general hierarchy of prioritization rules

PsycEXTRA Dataset ◽

10.1037/e577922012-007 ◽

2007 ◽

Author(s):

Guoxi Zhang ◽

Robert Feyen

Keyword(s):

Network Model ◽

Queueing Network ◽

Task Prioritization

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DEVELOPING AND SELECTING SLOPE STABILIZATION TECHNIQUES IN MANAGING SLOPE FAILURES

Jurnal Teknik Sipil ◽

10.24002/jts.v12i4.638 ◽

2016 ◽

Vol 12 (4) ◽

Author(s):

Ari Sandyavitri

Keyword(s):

Retaining Wall ◽

Value Engineering ◽

Rating Systems ◽

Slope Stabilization ◽

Rockfall Hazard ◽

Proactive Approach ◽

West Sumatra ◽

Hazard Rating ◽

Hazard Rating Systems ◽

Steep Slopes

This paper objectives are to; (i) identification of risky slopes (within 4 Provinces in Sumatra including Provinces of Riau, West Sumatra, Jambi and South Sumatra encompassing 840 kms of the “Jalan Lintas Sumatra” highway) based on Rockfall Hazard Rating Systems (RHRS) method; (ii) developing alternatives to stabilize slope hazards, and (iii) selecting appropriate slopes stabilization techniques based on both proactive approach and value engineering one. Based on the Rockfall Hazard Rating Systems (RHRS) method, it was identified 109 steep slopes prone to failure within this highway section. Approximately, 15 slopes were identified as potential high-risk slopes (RHRS scores were calculated >200 points). Based on the proactive approach, seven riskiest slopes ware identified. The preferred stabilization alternatives to remedy most of these slopes are suggested as follow; either (i) a combination of retaining wall and drainage, or (ii) gabion structure and drainage. However, different approaches may yield different results, there are at least 2 main consideration in prioritizing slope stabilization; (i) based on the riskiest slopes, and(ii) the least expensive stabilization alternatives.

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ANALYSIS OF AUTOMATIC TRANSMISSION USING FOURIER TRANSFORM INFRARED (FTIR) SPECTROCOPY

e-Academia Journal ◽

10.24191/e-aj.v7isi-temic18.5378 ◽

2019 ◽

Vol 7 (SI-TeMIC18) ◽

Author(s):

Norhanifah Abdul Rahman ◽

Matzaini Katon Katon ◽

Nurina Alya Zulkifli Zulkifli

Keyword(s):

Fourier Transform ◽

Automatic Transmission ◽

Fourier Transform Infrared ◽

Oil Analysis ◽

Wear Particles ◽

Reliable Technique ◽

Fluid Analysis ◽

Analysis Technique ◽

Machine Elements ◽

Transmission Fluid

Automatic Transmission (AT) system is efficient in the aspects of vehicle safety, comfort, reliability and driving performance. The objectives of this paper are to collect the oil samples from AT systems of engine bus according to manufacturer's recommendations and analyse collected oil samples using oil analysis technique. The sample transmission fluid which was taken from the AT gearbox has been experimentally analyzed. The oil samples were taken with an interval of 5,000km, 30,000km, 50,000km, 80,000km, 180,000km and 300,000km for AT bus operation. These samples then have been analyzed by comparing between new and used transmission fluid using Fourier Transform Infrared (FTIR) spectroscopy. Oil analysis by FTIR is a form of Predictive Maintenance (PdM) to avoid major failure in machine elements. Most machine elements are not easily accessible in the transmission system. Having a reliable technique would avoid the needs to open the components unnecessarily, hence, help to prevent catastrophic failure which are very costly, and ease of regular monitoring. In order to identify the major failures of automatic gearbox, forecasts can be made regarding the lube transmission fluid analysis test. By using this test, the minor problems can be determined before they become major failures. At the end of this research, the wear particles profile for interval mileage of AT system was obtained. Keywords: Wear, Automatic Transmission (AT), Transmission fluid, Fourier Transform Infrared (FTIR), Oil analysis.

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