bluuebunny/crossref_metadata_2025 huggingface dataset:
Inspection Technologies for Traditionally “Unpiggable” Liquid Pipelines
Authors: Higgins Amy , Dale Ryan , Ellestad Brian , McTavish Mark
Published: December 2014

Enbridge safely operates thousands of miles of piggable pipelines throughout North America. Within stations and terminals however, much of this piping has been uninspectable using conventional free-swimming in-line inspection technologies due to design and/or operating conditions. As a result, other direct assessment inspection techniques have been used to determine the condition of these assets. Seeing the need for smarter and more effective inspection and screening technologies for unpiggable pipes, many inspection tool vendors have developed new tools that can inspect these lines, although these often require pipe modifications.

The Enbridge’ Facilities Integrity group manages the integrity of all unpiggable piping and associated piping components associated with approximately 25 tank farms and over 150 pump stations. Inspections are planned based on a systematic analysis of integrity threats and consequence based risk factors. Inspection techniques are selected on a case-by-case basis to best manage the integrity of the asset based on the defined threats. Successful execution of these inspections is dependent on support from many functional areas. The effectiveness of the procedures for the planning, resources, inspection, repair/remediation, and incorporation of the findings is critical to the success of the program.

Enbridge is constantly looking for proven technology that will improve the integrity management of these assets. Enbridge is also actively supporting the development of new technologies that, once proven, will change the way we think about integrity management. Tethered inspection tools, bi-directional free swimming tools and tools that can navigate tight fittings and short radius bends are just a few of the new and innovative in-line inspection technologies Enbridge has been investigating over the past few years. In addition, Enbridge is currently involved in trials and validation of several inspection tools for the purposes of initial screening including guided wave technology, above ground screening methods, and tools that can detect corrosion under insulation.

This paper will discuss Enbridge’s experience with these new inspection technologies, highlighting the planning and preparation required to successfully complete these inspections, the benefits and challenges associated with these technologies, and the ongoing work being done to improve the application of these technologies in the future.
Assessment of an Existing Hot Tap Connection on the Bord Gáis Éireann Brighouse Bay Gas Export Terminal
Authors: Boothby Peter , Canty Graham , Andrews Robert , Slater Simon
Published: December 2014

A previous IPC conference paper (1) described the technical challenges associated with the installation of a new hot tap connection, supplementary to an existing hot tap connection, on the Bord Gáis Éireann Brighouse Bay high pressure gas export terminal in the UK. Work carried out to verify that the hot tap connection would be fit for purpose included a pipe stress analysis, Finite Element Analysis (FEA) and Engineering Critical Assessment (ECA). These assessments were performed because the split tee shell thickness and consequently also the circumferential fillet weld leg lengths did not achieve the 2 × carrier pipe thickness criterion required by UK specifications for applications where design stress levels exceed 30% specified minimum yield strength.

Subsequently, it was identified that the existing hot tap connection installed in 2001 also did not meet the 2 × carrier pipe thickness criterion. Furthermore the material grade was lower than that for newer hot tap, i.e. P355 compared with P460 and the tee had been chamfered down from 50 mm to 40 mm at the ends, leading to reduced section circumferential fillet welds. This resulted in a leaner design than that for the newer hot tap and an ASME B31.3 area replacement calculation revealed that the area replacement ratio barely achieved the 1.0 requirement of the code suggesting a limited tolerance to system loading. Consequently similar stress analysis, FEA and ECA assessments to those previously undertaken were also subsequently performed for the existing hot tap connection. This paper provides details of the analyses and results obtained to determine the integrity of the existing hot tap split tee assembly which required a bespoke approach and a need to challenge conventional thinking.
Direct Comparison of Single-Specimen Clamped SE(T) Test Methods on X100 Line Pipe Steel
Authors: Weeks Timothy S. , Lucon Enrico
Published: December 2014

The clamped single edge-notched tension (SE(T)) specimen has been widely used in a single-specimen testing scheme to generate fracture resistance curves for high strength line-pipe steels. The SE(T) specimen with appropriate notch geometry is a low-constraint specimen designed to reduce conservatism in the measurement of fracture toughness. The crack driving force is taken as either the J-integral or crack tip opening displacement (CTOD); it is generally accepted that the two parameters are interchangeable and equivalent using a simple closed form solution. However, the assumption that they are interchangeable, and to what extent, hasn’t been previously investigated experimentally on the same SE(T) specimen. This paper presents multiple test methods that were simultaneously employed on the same SE(T) specimens. The instrumentation includes: clip-gauges to measure surface crack mouth opening displacements (CMOD) and CTOD by the double-clip-gauge method; strain-gage arrays for direct J-integral measurements; and direct-current potential-drop (DCPD) instrumentation for supplementary crack size measurement. A direct comparison of ductile crack-growth resistance curves generated using J-integral and CTOD is presented here where each represents a different experimental and analytical approach. The two methods are in reasonable agreement over a narrow range of crack growth, differing slightly at initiation and diverging with increasing crack growth. Analysis of the supplementary instrumentation (i.e., strain gages, extensometers and DCPD) will be provided in a future publication.
Pipeline Integrity Data: Managing Past, Present, Future
Authors: Porter Todd , Donaho Darrell
Published: December 2014

The pipeline industry has recognized the need for an improved process to manage pipeline integrity data, in order to better serve the needs of; business, operations and engineering, to satisfy corporate governance requirements and state and federal regulatory compliance. The use of an industry data model such as Pipeline Open Data Standard (PODS), provides the foundational database structure for storing pipeline construction, operations and maintenance data. This provides an effective means to understand current state of the pipeline, but is not designed to store historical and large volume data sets.

Kinder Morgan along with other pipeline operators, presented a requirement and provided guidance on development of a Managed Integrity Data Process (MIDP) platform that augments typical PODS database implementations. This approach uses extensible methods and structure to further enable storage of the complete history of the pipeline and facilitate; time series analysis, trending, forecasting, and prioritization, to support integrity management decisions. The platform includes; data alignment tools for condition assessment from ILI/CIS surveys, management of pipeline history and providing an environment to deliver quick, accurate, and complete access to the integrity data via a WEB-UI.

In addition to storing pipeline condition information, the database architecture and surrounding process tools manage changes in pipeline position resulting from; relocation / reroutes, replacement and resurvey, while maintaining associated data attributes with these spatial location changes. The user has a complete GIS graphical view and synchronized tabular data view, showing changes to not only attributes, but changes in Class Location, HCA’s, and Risk results. This enables enhanced root cause, trend and forecasting capabilities. This paper will discuss; implementation, experience gained, and the value points within the various stakeholder groups, from the pipeline operator perspective.
Mechanical and Metallurgical Aspects of the Resistance to Ductile Fracture Propagation in the New Generation of Gas Pipelines
Authors: Pyshmintsev Igor , Gervasyev Alexey , Olalla Victor Carretero , Petrov Roumen , Arabey Andrey
Published: December 2014

The microstructure and fracture behavior of the base metal of different X80 steel line pipe lots from several pipeline projects were analyzed. The resistance of the pipes to ductile fracture propagation was determined by the full-scale burst tests. The high intensity of fracture surface separation (secondary brittle cracks parallel to the rolling plane of the plate) appeared to be the main factor reducing the specific fracture energy of ductile crack propagation. A method for quantitative analysis of microstructure allowing estimation of the steel’s tendency to form separations is proposed. The procedure is based on the EBSD data processing and results in Cleavage Morphology Clustering (CMC) parameter evaluation which correlates with full-scale and laboratory mechanical test results. Two special laboratory mechanical test types utilizing SENT and Charpy test concepts for prediction of ductile fracture arrest/propagation in a pipe were developed and included into Gazprom specifications.
Practical Applications of Bed Scour Calculations: Two Case Studies
Authors: Burge Leif M. , Chaput-Desrochers Laurence , Guthrie Richard
Published: December 2014

Pipelines can be exposed at water crossings where rivers lower the channel bed. Channel bed scour may cause damage to linear infrastructure such as pipelines by exposing the pipe to the flow of water and sediment. Accurate estimation of depth of scour is therefore critical in limiting damage to infrastructure. Channel bed scour has three main components: (1) general scour, (2) bed degradation, and (3) pool depth. General scour is the temporary lowering of the channel bed during a flood event. Channel bed degradation is the systematic lowering of a channel bed over time. Pool depth is depth of pools below the general bed elevation and includes the relocation of pools that result from river dynamics.

Channel degradation is assessed in the field using indicators of channel incision such as channel bed armoring and bank characteristics, through the analysis of long profiles and sediment transport modelling. Pool depth is assessed using long profiles and channel movement over time. The catastrophic nature of bed lowering due to general scour requires a different assessment. A design depth of cover is based on analysis of depth of scour for a given return period (eg. 100-years). There are three main steps to predict general scour: (1) regional flood frequency analysis, (2) estimation of hydraulic variables, and (3) scour depth modelling. Typically, four scour models are employed: Lacey (1930), Blench (1969), Neill (1973), and Zeller (1981), with the average or maximum value used for design depth.

We provide herein case studies for potential scour for pipeline water crossings at the Little Smoky River and Joachim Creek, AB. Using the four models above, and an analysis of channel degradation and pool depth, the recommended minimum depth of cover of 0.75 m and 0.142 m, respectively, were prescribed. Variability between scour models is large. The general scour model results varied from 0.45 m and 0.75 m for the Little Smoky River and 0.16 m to 0.51 m for Joachim Creek. While these models are more than 30 years old and do not adequately account for factors such as sediment mobility, they nevertheless do provide usable answers and should form part of the usual toolbox in water crossing scour calculations.
Managing Large Tank API 653 Re-Inspection Projects
Authors: Greaves Thomas H.
Published: December 2014

Every 20 years hydrocarbon storage tanks are taken out of service for API 653 mandated inspections and repairs. While the tanks are out of service other work is often completed. This paper chronicles the steps taken to ensure all the work is identified, budgeted for, scheduled, and completed in a timely and cost effective manner.

This paper assumes the reader has a working knowledge of atmospheric hydrocarbon storage tanks.
Improved thermal stability and electrical properties of atomic layer deposited HfO2/AlN high-k gate dielectric stacks on GaAs
Authors: Cao Yan-Qiang , Li Xin , Zhu Lin , Cao Zheng-Yi , Wu Di , Li Ai-Dong
Published: December 2014

The thermal stability and electrical properties of atomic layer deposited HfO2/AlN high-k gate dielectric stacks on GaAs were investigated. Compared to HfO2/Al2O3 gate dielectric, significant improvements in interfacial quality as well as electrical characteristics after postdeposition annealing are confirmed by constructing HfO2/AlN dielectric stacks. The chemical states were carefully explored by the x-ray photoelectron spectroscopy, which indicates the AlN layers effectively prevent from the formation of defective native oxides at elevated temperatures. In addition, it is found that NH3 plasma during AlN plasma-enhanced atomic layer deposition also has the self-cleaning effect as Al(CH3)3 in removing native oxides. The passivating AlN layers suppress the formation of interfacial oxide and trap charge, leading to the decrease of capacitance equivalent thickness after annealing. Moreover, HfO2/AlN/GaAs sample has a much lower leakage current density of 2.23 × 10−4 A/cm2 than HfO2/Al2O3/GaAs sample of 2.58 × 10−2 A/cm2. For the HfO2/AlN/GaAs sample annealed at 500 °C, it has a lowest interface trap density value of 2.11 × 1011 eV−1 cm−2. These results indicate that adopting HfO2/AlN dielectric stacks may be a promising approach for the realization of high quality GaAs-based transistor devices.
Foucault, Flying Discs and Calling Fouls: Ascetic Practices of the Self in Ultimate Frisbee
Authors: Crocket Hamish
Published: December 2014

Dominant analyses of sporting subjectivities suggest the contemporary athletic subject embodies a win-at-all-costs instrumental rationality. Yet, as Carless and Douglas (2012) argue, athletes are able to find less problematic alternatives to this understanding of sport. In this article, I use Foucault’s concept of “practices of the self” to undertake a sociological analysis of ethical subjectivities within Ultimate Frisbee. I focus specifically on ascetic, or self-controlling, practices of the self through which players create relationships between their self, Ultimate’s moral code and others. I use this case study to argue that ethical subjectivities offer a productive perspective for sociology of sport.
Use of transthoracic echocardiography in the evaluation of chest pain: illustrative cases and review of recent guidelines
Authors: Aldwaik Mohammed , Williams Aled P , Le Feuvre Simon , Cowell Richard
Published: December 2014

Chest pain (CP) is a very common presentation with a wide range of differential diagnoses, including life-threatening conditions, which need to be considered, diagnosed and treated urgently. Cardiac CP accounts for less than one-third of causes. Echocardiography is a valuable non-invasive tool that can help in diagnosing and treating patients presenting with CP. National Institute for Health and Care Excellence (NICE), European Society of Cardiology (ESC) and American Heart Association (AHA) guidelines state that echocardiography can help in the diagnosis of acute coronary syndromes and also in ruling out other serious conditions. We present three cases where transthoracic echocardiography (TTE) was essential in assessing patients, making the correct diagnosis and offering the right treatment. This article emphasises the importance of using TTE in assessing patients with CP and hopes to promote its consideration in day-to-day practice.
Zn(II) and Cu(II) removal byNostoc muscorum: a cyanobacterium isolated from a coal mining pit in Chiehruphi, Meghalaya, India
Authors: Goswami Smita , Diengdoh Omega L. , Syiem Mayashree B. , Pakshirajan Kannan , Kiran Mothe Gopi
Published: December 2014

Nostoc muscorum was isolated from a coal mining pit in Chiehruphi, Meghalaya, India, and its potential to remove Zn(II) and Cu(II) from media and the various biochemical alterations it undergoes during metal stress were studied. Metal uptake measured as a function of the ions removed by N. muscorum from media supplemented independently with 20 μmol/L ZnSO4and CuSO4established the ability of this cyanobacterium to remove 66% of Zn2+and 71% of Cu2+within 24 h of contact time. Metal binding on the cell surface was found to be the primary mode of uptake, followed by internalization. Within 7 days of contact, Zn2+and Cu2+mediated dissimilar effects on the organism. For instance, although chlorophyll a synthesis was increased by 12% in Zn2+-treated cells, it was reduced by 26% in Cu2+-treated cells. Total protein content remained unaltered in Zn2+-supplemented medium; however, a 15% reduction was noticed upon Cu2+exposure. Copper enhanced both photosynthesis and respiration by 15% and 19%, respectively; in contrast, photosynthesis was unchanged and respiration dropped by 11% upon Zn2+treatment. Inoculum age also influenced metal removal ability. Experiments in the presence of 3-(3,4-dichlorophenyl)-1,1-dimethylurea (a photosynthetic inhibitor), carbonyl cyanide m-chlorophenyl hydrazone (an uncoupler), and exogenous ATP established that metal uptake was energy dependent, and photosynthesis contributed significantly towards the energy pool required to mediate metal removals.
Dilong Prevents the High-KCl Cardioplegic Solution Administration-Induced Apoptosis in H9c2 Cardiomyoblast Cells Mediated by MEK
Authors: Han Chien-Kuo , Kuo Wei-Wen , Shen Chia-Yao , Chen Tung-Sheng , Pai Peiying , Tsai Chang-Hai , Lo Feng-Yueh , Ju Da-Tong , Huang Chih-Yang
Published: December 2014

Infusion of high-KCl cardioplegic solution (High-KCS) is the most common method used to induce asystole before cardiac surgery. However, our previous study showed the High-KCS can cause the apoptosis of cardiomyocytes in patients who were administered High-KCS prior to undergoing coronary artery bypass graft (CABG) to treat coronary artery disease (CAD). Therefore, it is urgent today to find a complementary medicine to reduce this damage. Dilong (earthworm) has been used as a traditional medicine in China for several thousand years, and extract from the Dilong has been empirically used in Asia for the treatment of vascular disorders. In this study, we applied Dilong extract to reduce myocardial cell damage from High-KCS infusion and further investigated the mechanisms. H9c2 cardiomyoblast cells were cultured in serum-free medium for 4 h and then treated with Dilong at 31.25, 62.5, 125, and 250 mg/mL for 24 h, which was then followed by High-KCS treatment for 3 h to detect the protective mechanisms of Dilong behind cardiomyocyte apoptosis and cardiac fibrosis. Cells were harvested for MTT assay, TUNEL assay, and western blot analysis. We found that High-KCS-induced cardiomyocyte apoptosis, enhanced the protein level of pro-apoptotic Bad, released cytochrome c, and activated caspase-3 in H9c2 cells. The IGF-I/IGF-IR/ERK pathway involved in non-cardiomyocyte proliferation, and the expression/activation of uPA, Sp-1 and CTGF, which are implicated in the development of cardiac fibrosis were up-regulated, but the Akt for cardiomyocyte survival was greatly deactivated in postcardioplegic H9c2 cardiomyoblast cells. However, Dilong was highly protective and totally reversed the apoptosis and cardiac fibrosis effects induced by High-KCS. Chemical inhibitors P38 (SB203580), JNK (SP600125), MEK (U0126), IGF-1 (AG1024), and PI3K (LY294002) were applied to investigate which is the mediator for Dilong attenuated High-KCS stimulated caspase 3 activation. MEK (U0126) inhibitor completely blocked Dilong inhibited caspase 3 activation in High-KCS treated H9c2 cells. The MEK siRNA was further applied to knockdown MEK to confirm our finding. We found Dilong worked through MEK to inhibit caspase 3 activity induced by High-KCS in H9c2 cells. Furthermore, we used the pure component of Dilong, Lumbrokinase, to block the High-KCS effect. Using the microscope to observe the cell viability, we found Lumbrokinase could reverse the High-KCS effect. Lumbrokinase could also reduce the protein levels of caspase 8, caspase 9, and caspase 3, and enhance the survival related proteins PI3K/Akt and Bcl2. These results demonstrate that Dilong could be used as a potential agent to block the side effects caused by High-KCS in CABG surgery patients.
Dynamic Singularity Spectrum Distribution of Sea Clutter
Authors: Xiong Gang , Yu Wenxian , Zhang Shuning
Published: December 2014

The fractal and multifractal theory have provided new approaches for radar signal processing and target-detecting under the background of ocean. However, the related research mainly focuses on fractal dimension or multifractal spectrum (MFS) of sea clutter. In this paper, a new dynamic singularity analysis method of sea clutter using MFS distribution is developed, based on moving detrending analysis (DMA-MFSD). Theoretically, we introduce the time information by using cyclic auto-correlation of sea clutter. For transient correlation series, the instantaneous singularity spectrum based on multifractal detrending moving analysis (MF-DMA) algorithm is calculated, and the dynamic singularity spectrum distribution of sea clutter is acquired. In addition, we analyze the time-varying singularity exponent ranges and maximum position function in DMA-MFSD of sea clutter. For the real sea clutter data, we analyze the dynamic singularity spectrum distribution of real sea clutter in level III sea state, and conclude that the radar sea clutter has the non-stationary and time-varying scale characteristic and represents the time-varying singularity spectrum distribution based on the proposed DMA-MFSD method. The DMA-MFSD will also provide reference for nonlinear dynamics and multifractal signal processing.
On KLJN-based Secure Key Distribution in Vehicular Communication Networks
Authors: Cao X. , Saez Y. , Pesti G. , Kish L. B.
Published: December 2014

In a former paper [Fluct. Noise Lett. 13 (2014) 1450020] we introduced a vehicular communication system with unconditionally secure key exchange based on the Kirchhoff-Law–Johnson-Noise (KLJN) key distribution scheme. In this paper, we address the secure KLJN key donation to vehicles. This KLJN key donation solution is performed lane-by-lane by using roadside key provider equipment embedded in the pavement. A method to compute the lifetime of the KLJN key is also given. This key lifetime depends on the car density and gives an upper limit of the lifetime of the KLJN key for vehicular communication networks.
Revisiting the Complexity of Hardware Cache Coherence and Some Implications
Authors: Komuravelli Rakesh , Adve Sarita V. , Chou Ching-Tsun
Published: December 2014

Cache coherence is an integral part of shared-memory systems but is also widely considered to be one of the most complex parts of such systems. Much prior work has addressed this complexity and the verification techniques to prove the correctness of hardware coherence. Given the new multicore era with increasing number of cores, there is a renewed debate about whether the complexity of hardware coherence has been tamed or whether it should be abandoned in favor of software coherence. This article revisits the complexity of hardware cache coherence by verifying a publicly available, state-of-the-art implementation of the widely used MESI protocol, using the Murφ model checking tool. To our surprise, we found six bugs in this protocol, most of which were hard to analyze and took several days to fix. To compare the complexity, we also verified the recently proposed DeNovo protocol, which exploits disciplined software programming models. We found three relatively easy to fix bugs in this less mature protocol. After fixing these bugs, our verification experiments showed that, compared to DeNovo, MESI had 15X more reachable states leading to a 20X increase in verification (model checking) time. Although we were eventually successful in verifying the protocols, the tool required making several simplifying assumptions (e.g., two cores, one address). Our results have several implications: (1) they indicate that hardware coherence protocols remain complex; (2) they reinforce the need for protocol designers to embrace formal verification tools to demonstrate correctness of new protocols and extensions; (3) they reinforce the need for formal verification tools that are both scalable and usable by non-expert; and (4) they show that a system based on hardware-software co-design can offer a simpler approach for cache coherence, thus reducing the overall verification effort and allowing verification of more detailed models and protocol extensions that are otherwise limited by computing resources.
Building and Optimizing MRAM-Based Commodity Memories
Authors: Wang Jue , Dong Xiangyu , Xie Yuan
Published: December 2014

Emerging non-volatile memory technologies such as MRAM are promising design solutions for energy-efficient memory architecture, especially for mobile systems. However, building commodity MRAM by reusing DRAM designs is not straightforward. The existing memory interfaces are incompatible with MRAM small page size, and they fail to leverage MRAM unique properties, causing unnecessary performance and energy overhead. In this article, we propose four techniques to enable and optimize an LPDDRx-compatible MRAM solution:
ComboAS
to solve the pin incompatibility;
DynLat
to avoid unnecessary access latencies; and
EarlyPA
and
BufW
to further improve performance by exploiting the MRAM unique features of non-destructive read and independent write path. Combining all these techniques together, we boost the MRAM performance by 17% and provide a DRAM-compatible MRAM solution consuming 21% less energy.
Volatile STT-RAM Scratchpad Design and Data Allocation for Low Energy
Authors: Rodríguez Gabriel , Touriño Juan , Kandemir Mahmut T.
Published: December 2014

On-chip power consumption is one of the fundamental challenges of current technology scaling. Cache memories consume a sizable part of this power, particularly due to leakage energy. STT-RAM is one of several new memory technologies that have been proposed in order to improve power while preserving performance. It features high density and low leakage, but at the expense of write energy and performance. This article explores the use of STT-RAM--based scratchpad memories that trade nonvolatility in exchange for faster and less energetically expensive accesses, making them feasible for on-chip implementation in embedded systems. A novel multiretention scratchpad partitioning is proposed, featuring multiple storage spaces with different retention, energy, and performance characteristics. A customized compiler-based allocation algorithm suitable for use with such a scratchpad organization is described. Our experiments indicate that a multiretention STT-RAM scratchpad can provide energy savings of 53% with respect to an iso-area, hardware-managed SRAM cache.
Efficient Out-of-Order Execution of Guarded ISAs
Authors: Prémillieu Nathanael , Seznec André
Published: December 2014

ARM ISA-based processors are no longer low-cost, low-power processors. Nowadays, ARM ISA-based processor manufacturers are striving to implement medium-end to high-end processor cores, which implies implementing a state-of-the-art out-of-order execution engine. Unfortunately, providing efficient out-of-order execution on legacy ARM codes may be quite challenging due to guarded instructions.

Predicting the guarded instructions addresses the main serialization impact associated with guarded instructions execution and the multiple definition problem. Moreover, guard prediction allows one to use a global branch-and-guard history predictor to predict both branches and guards, often improving branch prediction accuracy. Unfortunately, such a global branch-and-guard history predictor requires the systematic use of guard predictions. In that case, poor guard prediction accuracy would lead to poor overall performance on some applications.

Building on top of recent advances in branch prediction and confidence estimation, we propose a hybrid branch-and-guard predictor, combining a global branch history component and global branch-and-guard history component. The potential gain or loss due to the systematic use of guard prediction is dynamically evaluated at runtime. Two computing modes are enabled: systematic guard prediction use and high-confidence-only guard prediction use.

Our experiments show that on most applications, an overwhelming majority of guarded instructions are predicted. Therefore, a simple but relatively inefficient hardware solution can be used to execute the few unpredicted guarded instructions. Significant performance benefits are observed on most applications, while applications with poorly predictable guards do not suffer from performance loss.
"Driving curiosity in search with large-scale entity networks" by Ilaria Bordino, Mounia Lalmas, Yelena Mejova, and Olivier Van Laere with Martin Vesely as coordinator
Authors: Bordino Ilaria , Van Laere Olivier , Lalmas Mounia , Mejova Yelena
Published: December 2014

In many search scenarios, users sometimes find unexpected, yet interesting and useful results, which make them curious; they experience serendipity. This curiosity encourages them to explore further. We developed an entity search system designed to support such an experience.

The system explores the potential of entities extracted from two of the most popular sources of user-generated content -- Wikipedia, a user-curated online encyclopedia, and Yahoo Answers, a more unconstrained question & answering forum -- in promoting serendipitous search. The content of each data source is represented as a large network of entities, enriched with metadata about sentiment, writing quality, and topical category. A lazy random walk with restart is implemented to retrieve entities from the networks for a given entity query.

This paper discusses our work, focusing on our experience in designing, developing, and evaluating such a system. We also discuss the challenges in developing large-scale systems that aim to drive curiosity in search.
Searching for Sinks for the Hénon Map using a Multipleprecision GPU Arithmetic Library
Authors: Joldes Mioara , Popescu Valentina , Tucker Warwick
Published: December 2014

Today, GPUs represent an important hardware development platform for many problems in dynamical systems, where massive parallel computations are needed. Beside that, many numerical studies of chaotic dynamical systems require a computing precision higher than common oating point (FP) formats. One such application is locating invariant sets for chaotic dynamical systems. In particular, we focus on rigorously proving the existence of stable periodic orbits for the Hénon map for parameter values close to the classical ones. For that, we present a multiple-precision floating-point arithmetic library in CUDA programming language for the NVIDIA GPU platform. Our library extends the precision using so-called FP expansions, where a number is represented as the unevaluated sum of standard machine precision FP numbers. This format offers the advantage of using directly available and highly optimized hardware FP operations. We generalize algorithms used by multiple-precisions libraries such as Bailey's QD, or the analogue GPU version, GQD.
Declarative Networking
Authors: Ameloot Tom J.
Published: December 2014

We discuss recent theoretical results on declarative networking, in particular regarding the topics of coordination, correctness, and declarative semantics.
Public Data and Visualizations
Authors: Morton Kristi , Balazinska Magdalena , Grossman Dan , Kosara Robert , Mackinlay Jock
Published: December 2014

Recently, online visual analytics systems have emerged as popular tools for data analysis and sharing. The database community has an important role to play in shaping the design and implementation of these new types of systems. Little, however, is known about how these systems are used today. In this paper, we address this shortcoming by presenting an analysis of usage patterns of Many Eyes and Tableau Public, two popular Web-based, collaborative visual analytics systems.
Towards Total Traffic Awareness
Authors: Guo Chenjuan , Jensen Christian S. , Yang Bin
Published: December 2014

A combination of factors render the transportation sector a highly desirable area for data management research. The transportation sector receives substantial investments and is of high societal interest across the globe. Since there is limited room for new roads, smarter use of the existing infrastructure is of essence. The combination of the continued proliferation of sensors and mobile devices with the drive towards open data will result in rapidly increasing volumes of data becoming available. The data management community is well positioned to contribute to building a smarter transportation infrastructure. We believe that efficient management and effective analysis of big transportation data will enable us to extract transportation knowledge, which will bring significant and diverse benefits to society. We describe the data, present key challenges related to the extraction of thorough, timely, and trustworthy traffic knowledge to achieve total traffic awareness, and we outline services that may be enabled. It is thus our hope that the paper will inspire data management researchers to address some of the many challenges in the transportation area.
A Survey on XML Fragmentation
Authors: Braganholo Vanessa , Mattoso Marta
Published: December 2014

Efficient document processing is a must when large volumes of XML data are involved. In such critical scenarios, a well-known solution to this problem is to distribute (map) the data among several processing nodes, and then distribute the processing accordingly, taking advantage of parallelism. This is the approach taken by distributed databases and MapReduce environments. Fragmentation techniques play an important role in these scenarios. They provide a way to "cut" the database into pieces and distribute the pieces over a network. This way, queries can also be "cut" into sub-queries that run in parallel, thus achieving better performance when compared to the centralized environment. However, there is no consensus in the database community as to what an XML fragment is. In fact, several approaches in literature present definitions of XML fragments. In addition to query processing, using XML fragmentation techniques may also be helpful when managing XML documents distributed along the web or clouds. This paper surveys the existing XML fragmentation approaches in literature, comparing their features and highlighting their drawbacks. Our contribution resides in establishing a map of the area.
The Beckman Report on Database Research
Authors: Abadi Daniel , Agrawal Rakesh , Ailamaki Anastasia , Balazinska Magdalena , Bernstein Philip A. , Carey Michael J. , Chaudhuri Surajit , Dean Jeffrey , Doan AnHai , Franklin Michael J. , Gehrke Johannes , Haas Laura M. , Halevy Alon Y. , Hellerstein Joseph M. , Ioannidis Yannis E. , Jagadish H. V. , Kossmann Donald , Madden Samuel , Mehrotra Sharad , Milo Tova , Naughton Jeffrey F. , Ramakrishnan Raghu , Markl Volker , Olston Christopher , Ooi Beng Chin , Ré Christopher , Suciu Dan , Stonebraker Michael , Walter Todd , Widom Jennifer
Published: December 2014

Every few years a group of database researchers meets to discuss the state of database research, its impact on practice, and important new directions. This report summarizes the discussion and conclusions of the eighth such meeting, held October 14- 15, 2013 in Irvine, California. It observes that Big Data has now become a defining challenge of our time, and that the database research community is uniquely positioned to address it, with enormous opportunities to make transformative impact. To do so, the report recommends significantly more attention to five research areas: scalable big/fast data infrastructures; coping with diversity in the data management landscape; end-to-end processing and understanding of data; cloud services; and managing the diverse roles of people in the data life cycle.
Insider Threat Assessment
Authors: Nostro Nicola , Ceccarelli Andrea , Bondavalli Andrea , Brancati Francesco
Published: December 2014

Security is a major challenge for today's companies, especially ICT ones which manage large scale cyber-critical systems. Amongst the multitude of attacks and threats to which a system is potentially exposed, there are insider attackers i.e., users with legitimate access which abuse or misuse of their power, thus leading to unexpected security violation (e.g., acquire and disseminate sensitive information). These attacks are very difficult to detect and mitigate due to the nature of the attackers, which often are company's employees motivated by socio-economical reasons, and to the fact that attackers operate within their granted restrictions. It is a consequence that insider attackers constitute an actual threat for ICT organizations. In this paper we present our methodology, together with the application of existing supporting libraries and tools from the state-of-the-art, for insider threats assessment and mitigation. The ultimate objective is to define the motivations and the target of an insider, investigate the likeliness and severity of potential violations, and finally identify appropriate countermeasures. The methodology also includes a maintenance phase during which the assessment can be updated to reflect system changes. As case study, we apply our methodology to the crisis management system Secure!, which includes different kinds of users and consequently is potentially exposed to a large set of insider threats.
The TClouds Platform
Authors: Bessani Alysson , Cutillo Leucio A. , Ramunno Gianluca , Schirmer Norbert , Smiraglia Paolo
Published: December 2014

TClouds was an EU project (2010-2013) targeted at improving the security and the dependability of cloud infrastructures and services, especially for supporting critical applications. During the project, the participants of the consortium developed a platform containing a portfolio of solutions for improving the state of the art in cloud security and dependability. Here we present an overview of these solutions and two examples of how they can be integrated to provide security for critical cloud-based applications.
A General Mechanism Design Methodology for Social Utility Maximization with Linear Constraints
Authors: Sinha Abhinav , Anastasopoulos Achilleas
Published: December 2014

Social utility maximization refers to the process of allocating resources in a way that maximizes the sum of agents' utilities, under the system constraints. Such allocation arises in several problems in the general area of communications, including unicast (and multicast multi-rate) service on the Internet, as well as in applications with (local) public goods, such as power allocation in wireless networks, spectrum allocation, etc. Mechanisms that implement such allocations in Nash equilibrium have also been studied but either they do not possess the full implementation property, or are given in a case-by-case fashion, thus obscuring fundamental understanding of these problems. In this paper we propose a unified methodology for creating mechanisms that fully implement, in Nash equilibria, social utility maximizing functions arising in various contexts where the constraints are convex. Two additional design goals are the focus of this paper: a) the size of the message space scaling linearly with the number of agents (even if agents' types are entire valuation functions), b) allocation being feasible on and off equilibrium.
Proof of Activity
Authors: Bentov Iddo , Lee Charles , Mizrahi Alex , Rosenfeld Meni
Published: December 2014

We propose a new protocol for a cryptocurrency, that builds upon the Bitcoin protocol by combining its Proof of Work component with a Proof of Stake type of system. Our Proof of Activity protocol offers good security against possibly practical attacks on Bitcoin, and has a relatively low penalty in terms of network communication and storage space.
Experimenting ResourceonDemand Strategies for Green WLANs
Authors: Debele Fikru Getachew , Li Nanfang , Meo Michela , Ricca Marco , Zhang Yi
Published: December 2014

WLAN becomes a necessary facility for exible Internet provisioning in enterprise networks. Usually this connection provisioning is designed to handle a peak load with high density of Access Points (APs) to guarantee a desired level of quality of service (QoS). This design approach however leads to energy inefficiency due to the daily demand variability. In fact the off-peak period of the daily behavior is usually quite long and hence some resources consume power without any beneficiary activity. Resource-on-demand (RoD) provisioning is among foreseeable solutions that satisfy both energy efficiency as well as QoS constraints. That is the network capacity is dynamically dimensioned to demand while extra resource goes to low energy consumption mode to save energy. In dense WLAN scenarios, extra APs are turned off during low load until required due to increase in demand.

Some theoretical analysis of RoD has been proposed by related works, but experiments on real production networks are still needed in order to investigate the practical issues related to RoD strategies. This paper addresses some of these issues through an experimental activity performed on RoD strategies. Two strategies, namely association-based and traffic-based policies, are implemented in one part of Politecnico di Torino Campus WLAN. Results from our testbed show that RoD strategies are effective and energy saving up to 70% is possible.
Familial Discoid Medial Meniscus Tear in Three Members of a Family: A Case Report and Review of Literature
Authors: Ahmed Ali Raheel , McKay Scott
Published: December 2014

Background. A discoid meniscus is a thickened variant of the normal C-shaped meniscus prone to injury. Discoid medial meniscal tears have rarely been reported within families and may suggest familial or developmental origins.Methods. We report the cases of two Caucasian brothers with symptomatic discoid medial meniscus tears. A literature review was conducted addressing discoid medial meniscus and cases of familial meniscus tears.Case Presentation. Physically active brothers presented with progressively worsening knee pain. MRI revealed medial meniscus tears in both brothers. The family history of medial meniscus tears in their mother and the discoid medial meniscus injuries found on arthroscopy suggested evidence for familial discoid medial meniscus tears.Conclusions. Discoid medial meniscus tears within a family have not been previously reported. Two cases of families with discoid lateral meniscus tears have been reported. Discoid medial meniscus is rare relative to the discoid lateral meniscus and predisposes children to symptomatic tears.
Hybrid Fingerprinting-EKF Based Tracking Schemes for Indoor Passive Localization
Authors: Bybordi Salar , Reggiani Luca
Published: December 2014

This paper investigates a combination of fingerprinting (FP) and extended Kalman filter (EKF) based tracking aiming to tackle conventional problems related to implementation of either tracking or fingerprinting separately. One of the common drawbacks of FP belongs to large data size and consequent large search space. By taking advantage of latest position estimate got from EKF, a virtual surveillance area (VSA) is defined around the estimate. The dimension of this defined surveillance area is much smaller than the size of indoor environment. Consequently, there will be a possibility for FP to be applied in larger areas maintaining the possibility of adding necessary grid points in order to achieve a desired localization performance. Additionally, in order to improve accuracy of ranging, we investigate the impact of a priori knowledge related to the clusters impulse responses and other features; the applied so called soft ranging algorithm for time of arrival (TOA) estimation is modified in order to take advantage of this a priori information and to make its decision variables more accurate. Simulation results show a promising performance improvement via using the proposed hybrid tracking technique and applying a priori information to soft ranging. The tradeoff is along a reasonable increased implementation complexity.
Occult Papillary Thyroid Carcinoma Metastasis to the Sacrum and the Skull: An Unusual Presentation
Authors: Jouhar Fatima S. , Quadri Asif , Afandi Bachar , Al Rawi Sadir
Published: December 2014

This case represents occult follicular variant of papillary thyroid carcinoma (FVPTC) with large metastasis to the sacrum. The patient, a 42-year-old female, presented after hemithyroidectomy for benign follicular adenoma with lower back pain associated with fever and sweating. A lytic lesion of the left sacral bone was found on the CT with biopsy showing metastatic carcinoma with morphology and immunophenotype of thyroid gland primary tumor proven to be FVPTC. The patient had completion thyroidectomy with benign pathology.
Flow Cytometric Enumeration of Parasitemia in Cultures ofPlasmodium falciparumStained with SYBR Green I and CD235A
Authors: Jang Jin Woo , Kim Ju Yeon , Yoon Jung , Yoon Soo Young , Cho Chi Hyun , Han Eun Taek , An Seong Soo A. , Lim Chae Seung
Published: December 2014

A flow cytometric (FACS) detection method forPlasmodium falciparumcultures (P. falciparum) was developed using SYBR Green I and CD235A and compared against the Giemsa stained microscopic examination. The culturedP. falciparumwere spiked into red blood cells (RBCs) to yield parasitemia, ranging from 0.01% to 22.0%. FACS analysis demonstrated a clear separation betweenP. falciparuminfected and uninfected RBCs. The measured percentage of parasitemia by FACS revealed higher precision (CV of 2.2–37.2%) with the sensitivity of 0.01% parasitemia than Giemsa stained microscopic examination (CV of 7.2–66.0%). High correlation of measured parasitaemia (r=0.98,P<0.05) was observed between FACS and Giemsa stained microscopic analyses. The higher levels of parasitaemia detection were observed in all ranges by FACS in comparison to Giemsa stained microscopic analysis. The currently reported FACS method using SYBR Green I and CD235A is potentially useful for measuring parasitemia in treating patients.
Is Overweight a Risk Factor for Adverse Events during Removal of Impacted Lower Third Molars?
Authors: de Carvalho Ricardo Wathson Feitosa , do Egito Vasconcelos Belmiro Cavalcanti
Published: December 2014

Being overweight is recognised as a significant risk factor for several morbidities; however, the experience of the dentistry faculties focusing on this population is still low. The aim of the present study was to determine the occurrence of adverse events during removal of impacted lower third molars in overweight patients. A prospective cohort study was carried out involving overweight patients subjected to surgical removal of impacted lower third molar as part of a line of research on third molar surgery. Predictor variables indicative of the occurrence of adverse events during surgery were classified by their demographic, clinical, radiographic, and surgical aspects. Descriptive and bivariate statistics were computed. In total, 140 patients fulfilled the eligibility criteria, and 280 surgeries were performed. Patients’ mean age was25.1 ± 2.2 years, and the proportion of women to men was 3 : 1. Eight different adverse events during surgery were recorded. These events occurred in approximately 29.3% of cases and were significantly associated with predictor variables (P < 0.05). Excess weight is recognised as a risk factor for the high rate of adverse events in impacted third molar surgery. The study suggests that overweight patients are highly likely to experience morbidities.