Abstract

Interoperability in logistics is a prerequisite for realizing data pipelines and the Physical Internet. Forecasting data, real time data, and actual positions of shipments, containers, and transport means shared via events have to be harmonized and are expected to improve all types of processes, support synchromodal planning, and improve risk analysis from a compliance and resilience perspective. Technically, several solutions are implemented by organizations and innovations have been validated in so-called Living Labs or demonstrators in various projects. These solutions do not yet provide open systems required for a (global) data pipeline. A federation of solutions is required to construct data pipelines and to support sustainable development of applications on smart devices allowing Small and Medium sized Enterprises to collaborate. This paper proposes a set of platform services and so-called platform protocols to allow interoperability of different platforms for constructing a data pipeline. The proposed services and protocols further extend existing interoperability solutions and services for supply and logistics. © IFIP International Federation for Information Processing 2015. Document type: Part of book or chapter of book

Abstract

International audience; Burn-In (BI) test is usually applied in manufacturing process to screen out chip early life failures, especially for safety critical applications. Unfortunately, this test method has elevated costs for companies. In recent days, Faster-than-at-Speed-Test (FAST) has become a useful technique to discover small delay defects. At the same time, overclocking methods to enhance system performances have been studied, which focus on temperature management to preserve system functionalities. In this paper, a FAST technique is approached with the aim of intentionally provoking a thermal overheating in the microprocessor by mean of the execution of functional test programs, partly regardless of system behavior preservation. The goal is to introduce an internal stress stronger than current procedures used during BI in order to speed up early detection of latent faults. The method illustrates how to avoid blocking configurations due to timing constraints violation and leads to a significant increase of the switching activity. Experimental results on a MIPS architecture show that, by using the described technique, the processor is not falling into an unpredictable state even at frequencies up to about 20 times higher than the nominal one and the switching activity is increasing up to 300% per nanoseconds.

Abstract

Network operators have recently been developing multi-Gbps traffic monitoring tools that execute on commodity hardware and are part of the packet-processing pipelines realizing software dataplanes. These solutions allow sophisticated tasks to be performed on a per-packet basis, without relying on sampling or passive trace analysis, by leveraging the processing power available on servers. Although advances in packet capture have enabled intercepting packets from network cards at high rates, bottlenecks can still arise in the monitoring process as a result of concurrent access to shared processor resources, variations of the traffic skew, and unbalanced packet-rate spikes. In this paper we present an adaptive traffic monitoring approach that copes with emerging bottlenecks by timely detecting changes in the operational conditions and reconfiguring monitoring-related operations for subsets of traffic flows. Our solution performs responsive adaptations at the time scale of milliseconds and does not require a significant amount of resources. To demonstrate the capabilities of our approach we implemented it as part of a generic packet-processing pipeline and show that lossless traffic monitoring can be achieved for a wide range of conditions.

Abstract

Through complementary experimental and numerical efforts, the present paper aims to make a significant contribution to the overall understanding of backfilling processes beneath submarine pipelines. For this purpose, we aim to simplify the experimental backfilling process to an elementary two-stage process: (1) initial scour induced by a pure current, followed by: (2) backfilling induced by pure waves. A steady current is introduced via a re-circulating pump, and is kept constant with a cross-sectional velocity of V = 0.48 m/s until an initial equilibrium scour depth, S0, is reached. Then, the current is stopped and waves (characterized by their Keulegan-Carpener number KC and Shields parameter θ)are introduced to initiate the backfilling process, which is maintained until a new equilibrium scour depth, Sf, is reached. The time at which waves are introduced will be denoted as t = 0. For the backfilling process both regular and irregular waves are used during the experiments. As a demonstration of the initiated two-stage (scour followed by backfilling) process, bed profiles based on video recordings from a case having KC = 9.7 and ϴ = 0.195,are depicted at selected stages in Figure 1. Figure 1(upper left) depicts the current-induced equilibrium scour hole in the near vicinity of the pipe at t = 0, with the profile approximated as the dashed red line. Similarly, Figure 1(upper right) depicts the new equilibrium scour profile (approximated as the full blue line) that has developed under wave-induced backfilling, corresponding to t = 60min. To ease comparison, the dashed red and full bluelines from these plots are additionally combined onto Figure 1 (bottom).The experimental campaign has additionally been complemented with similar numerical simulations (using regular waves), based on a fully-coupled hydrodynamicand morphodynamic CFD model (Jacobsen et al., 2014),extending previous pipeline scour-related applications ofFuhrman et al. (2014) and Larsen et al. (2016). Comparison of the numerical and experimental results demonstrate the ability of the CFD model to reasonably simulate the current-to-wave backfilling process, both interms of the achieved new wave induced equilibriumscour depths as well as the corresponding backfilling timescales. Figure 2 depicts a summary of both experimental and numerical backfilling time scale Tb versus Shields parameter θ. As can be seen, both experimental as well as numerical results match the regression equation:T"sub"b"/sub"=0.3 θ-"sup"5/3 "/sup"quite closely (solid line in Figure 2).

Abstract

Background"/jats:title""jats:p"The complex nature of biological data has driven the development of specialized software tools. Scientific workflow management systems simplify the assembly of such tools into pipelines, assist with job automation and aid reproducibility of analyses. Many contemporary workflow tools are specialized and not designed for highly complex workflows, such as with nested loops, dynamic scheduling and parametriza-tion, which is common in e.g. machine learning."/jats:p""/jats:sec""jats:sec""jats:title"Findings"/jats:title""jats:p"SciPipe is a workflow programming library implemented in the programming language Go, for managing complex and dynamic pipelines in bioinformatics, cheminformatics and other fields. SciPipe helps in particular with workflow constructs common in machine learning, such as extensive branching, parameter sweeps and dynamic scheduling and parametrization of downstream tasks. SciPipe builds on Flow-based programming principles to support agile development of workflows based on a library of self-contained, reusable components. It supports running subsets of workflows for improved iterative development, and provides a data-centric audit logging feature that saves a full audit trace for every output file of a workflow, which can be converted to other formats such as HTML, TeX and PDF on-demand. The utility of SciPipe is demonstrated with a machine learning pipeline, a genomics, and a transcriptomics pipeline."/jats:p""/jats:sec""jats:sec""jats:title"Conclusions"/jats:title""jats:p"SciPipe provides a solution for agile development of complex and dynamic pipelines, espe-cially in machine leaning, through a flexible programming API suitable for scientists used to programming or scripting."/jats:p""/jats:sec Document type: Article

Abstract

International audience; In this paper, ant colony optimization algorithm (ACOA) is proposed to solve the problem of how to efficiently operate a natural gas pipeline under steady state assumptions. The system is composed by compressing stations linked by pipe-legs. For each station, it is necessary to find the operating turbocompressors optimal values and the discharge pressures ones to minimize the total amount of fuel gas consumed in the system by the compressor stations. In the past, several techniques ranging from classical gradient-based procedures to dynamic programming, for solving this no convex problem have been applied. In this paper, we propose the ant colony optimization metaheuristic. This method was applied to the gas pipeline Hassi R' mell- ARZEW (two cities in Algeria) and the results are compared with those obtained by employing dynamic programming method. From these results, we obtain that the ACO technique is an interesting way for the gas pipeline operations optimization.

Abstract

The presence of buried landmines is a serious threat in many areas around the World. Despite various techniques have been proposed in the literature to detect and recognize buried objects, automatic and easy to use systems providing accurate performance are still under research. Given the incredible results achieved by deep learning in many detection tasks, in this paper we propose a pipeline for buried landmine detection based on convolutional neural networks (CNNs) applied to ground-penetrating radar (GPR) images. The proposed algorithm is capable of recognizing whether a B-scan profile obtained from GPR acquisitions contains traces of buried mines. Validation of the presented system is carried out on real GPR acquisitions, albeit system training can be performed simply relying on synthetically generated data. Results show that it is possible to reach 95% of detection accuracy without training in real acquisition of landmine profiles. Document type: Conference object

Abstract

Composite repair systems are used for many years to restore locally the pipe strength where it has been affected by damage such as wall thickness reduction due to corrosion, dent, lamination or cracks."/jats:p" "jats:p"Composite repair systems are commonly qualified, designed and installed according to ASME PCC2 code or ISO 24817 standard requirements. In both of these codes, the Maximum Allowable Working Pressure (MAWP) of the damaged section must be determined to design the composite repair. To do so, codes such as ASME B31G for example for corrosion, are used. The composite repair systems is designed to “bridge the gap” between the MAWP of the damaged pipe and the original design pressure."/jats:p" "jats:p"The main weakness of available approaches is their applicability to combined loading conditions and various types of defects. The objective of this work is to set-up a “universal” methodology to design the composite repair by finite element calculations with directly taking into consideration the loading conditions and the influence of the defect on pipe strength (whatever its geometry and type)."/jats:p" "jats:p"First a program of mechanical tests is defined to allow determining all the composite properties necessary to run the finite elements calculations. It consists in compression and tensile tests in various directions to account for the composite anisotropy and of Arcan tests to determine steel to composite interface behaviors in tension and shear. In parallel, a full scale burst test is performed on a repaired pipe section where a local wall thinning is previously machined. For this test, the composite repair was designed according to ISO 24817."/jats:p" "jats:p"Then, a finite element model integrating damaged pipe and composite repair system is built. It allowed simulating the test, comparing the results with experiments and validating damage models implemented to capture the various possible types of failures. In addition, sensitivity analysis considering composite properties variations evidenced by experiments are run."/jats:p" "jats:p"The composite behavior considered in this study is not time dependent. No degradation of the composite material strength due to ageing is taking into account. The roadmap for the next steps of this work is to clearly identify the ageing mechanisms, to perform tests in relevant conditions and to introduce ageing effects in the design process (and in particular in the composite constitutive laws).

Abstract

Re-using depleted fields (and platforms and wells) offers advantages over developing storage projects in saline formations. However, with reservoir pressures after production sometimes below 20 bar, there can be a large pressure difference between the reservoir and the transport pipeline at the surface, which will be typically at pressures in the range of 80 - 120 bar. This pressure difference must be carefully managed to ensure that the temperature of the CO2, the surface installations and the well, remain within materials specifications and within proper operating boundaries. Pressure drops of the CO2 result in potentially large decrease in temperature, due to its high Joule-Thomson coefficient; in addition, the temperatures and pressures that occur in a typical CO2 transport and storage system are such that two-phase flow is likely to occur. Pipeline pressure and temperature management can easily be done in a single source- single sink scenario as the pipeline pressure is a free parameter. However, if the pipeline must act as a backbone for multiple wells at different reservoir pressure, pressure and flow management must be balanced carefully. In this paper, the differences between a pipeline as transport and a pipeline as backbone will be discussed in detail.

Abstract

International audience; CMOS technology trends at one side open up some opportunities like making small and power efficient devices available, which in turn allow to put more functionality into a single chip. However, on the other side it poses some challenges like making devices vulnerable to hard and soft errors. In this paper we propose an efficient fault-tolerant architecture able to deal with permanent and transient faults in combinational parts of pipeline structures. The principle consists in triplicating the combinational logic parts but, unlike TMR, only two copies are running in parallel while the third one remains in standby until an error is detected. We implement this approach on a MIPS microprocessor as case study to make it resilient against transient and permanent faults.