2,887 research outputs found

    Does Big Data Require Complex Systems? A Performance Comparison Between Spark and Unicage Shell Scripts

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    The paradigm of big data is characterized by the need to collect and process data sets of great volume, arriving at the systems with great velocity, in a variety of formats. Spark is a widely used big data processing system that can be integrated with Hadoop to provide powerful abstractions to developers, such as distributed storage through HDFS and resource management through YARN. When all the required configurations are made, Spark can also provide quality attributes, such as scalability, fault tolerance, and security. However, all of these benefits come at the cost of complexity, with high memory requirements, and additional latency in processing. An alternative approach is to use a lean software stack, like Unicage, that delegates most control back to the developer. In this work we evaluated the performance of big data processing with Spark versus Unicage, in a cluster environment hosted in the IBM Cloud. Two sets of experiments were performed: batch processing of unstructured data sets, and query processing of structured data sets. The input data sets were of significant size, ranging from 64 GB to 8192 GB in volume. The results show that the performance of Unicage scripts is superior to Spark for search workloads like grep and select, but that the abstractions of distributed storage and resource management from the Hadoop stack enable Spark to execute workloads with inter-record dependencies, such as sort and join, with correct outputs.Comment: 10 pages, 14 figure

    External Corrosion of the bottom plate of Petroleum and Derivative Storage tanks on Compacted Soils

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    Inspections carried out on petroleum and derivative storage tanks on compacted soils have shown external corrosion on the bottom plates of the tanks despite cathodic protection by an impressed current. The holes or cavities in the outer plates of the bottom of the tank (in contact with the soil) result in oil leakage, thereby having significant environmental impacts. The objective of this paper is to show, in laboratory experiments, that cathodic protection is not reliable when there are voids or spaces between the plates and the soil. In addition, it proposes the application of a thermal spray with aluminium in the parts of the bottom plates that are in contact with the soil to protect these plates from localised corrosion. It is important to note that the welding temperature was 320°C, without affecting the aluminium coating applied by the thermal spray

    A novel methodology for the concurrent test of partial and dynamically reconfigurable SRAM-based FPGAs

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    This poster presents the first truly non-intrusive structural concurrent test approach, with the objective of testing partially and dynamically reconfigurable SRAM-based FPGAs without disturbing their operation. This is accomplished by using a new methodology to carry out the replication of active Configurable Logic Blocks (CLBs), i.e. CLBs that are part of an implemented function that is actually being used by the system, releasing it to be tested in a way that is completely transparent to the system

    Run-time management of logic resources on reconfigurable systems

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    Dynamically reconfigurable systems based on partialand dynamically reconfigurable FPGAs may have theirfunctionality partially modified at run-time withoutstopping the operation of the whole system.The efficient management of the logic space availableis one of the biggest problems faced by these systems.When the sequence of reconfigurations to be performed isnot predictable, resource allocation decisions have to bemade on-line. A rearrangement may be necessary to getenough contiguous space to implement incomingfunctions, avoiding the spreading of their components andthe resulting degradation of system performance.A new software tool that helps to handle the problemsposed by the consecutive reconfiguration of the same logicspace is presented in this paper. This tool uses a novel on--line rearrangement procedure to solve fragmentationproblems and to rearrange the logic space in a waycompletely transparent to the applications currentlyrunnin

    Programmable logic devices: a test approach for the Input / Output blocks and Pad-to-Pin interconnections

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    Dynamically reconfigurable systems based on partial and dynamically reconfigurable FPGAs may have their functionality partially modified at run-time without stopping the operation of the whole system. The efficient management of the logic space available is one of the biggest problems faced by these systems. When the sequence of reconfigurations to be performed is not predictable, resource allocation decisions have to be made on-line. A rearrangement may be necessary to get enough contiguous space to implement incoming functions, avoiding the spreading of their components and the resulting degradation of system performance.A new software tool that helps to handle the problems posed by the consecutive reconfiguration of the same logic space is presented in this paper. This tool uses a novel on-line rearrangement procedure to solve fragmentation problems and to rearrange the logic space in a way completely transparent to the applications currently running

    Enterprise information portals: potential for evaluating research for knowledge management and human capital assets using social network analysis

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    Paper presented at the ECKM 2010 – 11th European Conference on Knowledge Management, 2-3 September, 2010, Famalicão, Portugal. URL: http://www.academic-conferences.org/eckm/eckm2010/eckm10-home.htmEnterprise Information Portals (EIP) are being increasingly referred in the literature as one interesting technological solution to support organizations in their knowledge management initiatives. This paper seeks to explore the hidden potential of enterprise information portals to support knowledge management initiatives through the usage of social network analysis on research results and co-authorship/co-work relationships that may suggest ways to more effectively utilize knowledge capital and other organizational resources. For that purpose in this paper we will present field research results on evaluating knowledge management and human capital assets based on EIP data repositories using social network analysis. This evaluation will be made through the use of social network analysis techniques applied to authorship data from papers published in international journals with refereeing covering the last twenty years of research activities from a Portuguese leading research institution in the field of telecommunications - Instituto de Telecomunicações (IT)

    Thermal analysis evaluation of mechanical properties changes promoted by gamma radiation on surgical polymeric textiles

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    The large number of surgical operations with pos-operative infection problems and the appearing of new infectious diseases, contribute to the development of new materials in order to answer the needs of health care services. This development must take into account the modifications promoted by sterilisation methods in materials, namely by gamma radiation. The Differential Scanning Calorimetry (DSC) and Thermogravimetry (TGA) techniques show that a nonwoven and a laminate textiles maintain a good molecular cohesion, do not showing high levels of degradation, for gamma radiation dose values lower than 100 kGy in nonwoven and 200 kGy in laminate materials. The tensile strength and the elongation decrease slowly for the nonwoven textile and decrease faster for the laminate textile for 25 and 80 kGy absorbed dose. This paper shows that the DSC and TGA techniques can be helpful for the prevision of mechanical changes occurred in the materials as a consequence of the gamma irradiation

    A versatile nanocarrierCubosomes, characterization, and applications

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    The impact of nanotechnology on the exponential growth of several research areas, particularly nanomedicine, is undeniable. The ability to deliver active molecules to the desired site could significantly improve the efficiency of medical treatments. One of the nanocarriers developed which has drawn researchers’ attention are cubosomes, which are nanosized dispersions of lipid bicontinuous cubic phases in water, consisting of a lipidic interior and aqueous domains folded in a cubic lattice. They stand out due to their ability to incorporate hydrophobic, hydrophilic, and amphiphilic compounds, their tortuous internal configuration that provides a sustained release, and the capacity to protect and safely deliver molecules. Several approaches can be taken to prepare this structure, as well as different lipids like monoolein or phytantriol. This review paper describes the different methods to prepare nanocarriers. As it is known, the physicochemical properties of nanocarriers are very important, as they influence their pharmacokinetics and their ability to incorporate and deliver active molecules. Therefore, an extensive characterization is essential to obtain the desired effect. As a result, we have extensively described the most common techniques to characterize cubosomes, particularly nanocarriers. The exceptional properties of the cubosomes make them suitable to be used in several applications in the biomedical field, from cancer therapeutics to imaging, which will be described. Taking in consideration the outstanding properties of cubosomes, their application in several research fields is envisaged.This study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UIDB/04469/2020 unit, by Marie Skłodowska Curie grant (MSCA-RISE; FODIAC; 778388) and by European Regional Development Fund (ERDF) through the Competitiveness factors Operational program—Norte 2020, COMPETE and National Funds through the FCT—under the project AgriFood XXI (NORTE- 01-0145-FEDER-000041). J.L.P. acknowledge the Instituto de Salud Carlos III for a “Sara Borrell” grant (CD19/00250), cofounded by European Social Fund (“El FSE invierte en futuro”). C.J.O.F. acknowledge the FCT for the grant SFRH/149/BD/14199/2019.info:eu-repo/semantics/publishedVersio

    Advancements in on-line monitoring and control of parameters in knitting and sewing processes

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    This paper presents a summary of the developments in process control in textile processes at the University of Minho, by a multidisciplinary research group involving three different departments (Textile, lectronic and Mechanical Engineering). The studies target the automatic process parameter monitoring and control in the areas of industrial sewing and knitting.Fundação para a Ciência e a Tecnologia (FCT)

    Depression and conservative surgery for breast cancer

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    BACKGROUND: Depression is prevalent among women and associated with reduced quality of life, and therefore it is important to determine its incidence in adult women, especially in those with breast cancer. OBJECTIVE: To determine the occurrence of depression in women who underwent conservative surgery for breast cancer with or without breast reconstruction. METHODS: Seventy-five women aged between 18 and 65 years were enrolled. Patients had undergone conservative surgery for breast cancer with immediate breast reconstruction (n = 25) or without breast reconstruction (n = 25) at least one year before the study. The control group consisted of 25 women without cancer, but of similar age and educational level distribution as the other two groups. The Beck Depression Inventory was used to measure depression. The collected data were assessed using analysis of variance and the χ2 test. RESULTS: There were no significant differences between groups in age (p = 0.72) or educational level (p = 0.20). A smaller number of patients had undergone the menopause (p = 0.02) in the control group than in other groups. There were no significant differences in occurrence of depression between groups (χ2=9.97; p = 0.126). CONCLUSÍON: Conservative surgery for breast cancer did not affect the occurrence of depression in women, regardless of whether breast reconstruction was performed
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