Search results for "computer.file_format"
showing 10 items of 214 documents
A comparison of HDFS compact data formats: Avro versus Parquet
2017
In this paper, file formats like Avro and Parquet are compared with text formats to evaluate the performance of the data queries. Different data query patterns have been evaluated. Cloudera’s open-source Apache Hadoop distribution CDH 5.4 has been chosen for the experiments presented in this article. The results show that compact data formats (Avro and Parquet) take up less storage space when compared with plain text data formats because of binary data format and compression advantage. Furthermore, data queries from the column based data format Parquet are faster when compared with text data formats and Avro. Article in English. HDFS glaustųjų duomenų formatų palyginimas: Avro prieš Parquet…
A sensor-data-based denoising framework for hyperspectral images
2015
Many denoising approaches extend image processing to a hyperspectral cube structure, but do not take into account a sensor model nor the format of the recording. We propose a denoising framework for hyperspectral images that uses sensor data to convert an acquisition to a representation facilitating the noise-estimation, namely the photon-corrected image. This photon corrected image format accounts for the most common noise contributions and is spatially proportional to spectral radiance values. The subsequent denoising is based on an extended variational denoising model, which is suited for a Poisson distributed noise. A spatially and spectrally adaptive total variation regularisation term…
Angiocardiographic digital still images compressed via irreversible methods: concepts and experiments.
1997
Abstract We defined, implemented and tested two new methods for irreversible compression of angiocardiographic still images: brightness error limitation (BEL) and pseudo-gradient adaptive brightness and contrast error limitation (PABCEL). The scan path used to compress the digital images is based on the Peano–Hilbert plane-filling curve. The compression methods limit, for each pixel, the brightness errors introduced when approximating the original image (i.e. the difference between the values of corresponding pixels as grey levels). Additional limitations are imposed to the contrast error observed when considering along the scan path consecutive pixels of both the original and the reconstru…
Domain-Specific Characteristics of Data Quality
2017
The research discusses the issue how to describe data quality and what should be taken into account when developing an universal data quality management solution. The proposed approach is to create quality specifications for each kind of data objects and to make them executable. The specification can be executed step-by-step according to business process descriptions, ensuring the gradual accumulation of data in the database and data quality checking according to the specific use case. The described approach can be applied to check the completeness, accuracy, timeliness and consistency of accumulated data.
HL7v3 CDA Rel.2 Patient Summary and Chronic Care Model: Localization experience and GP/HS Integration Project
2010
The localization experience for the Patient Summary, based on the Health Level Seven Version 3 (HL7v3) Clinical Document Architecture, Release 2 (CDA Rel.2), is presented. An overview of the Chronic Care Model (CCM) is introduced with particular attention to the clinical information systems, in order to organize patient and population clinical data by sharing information among healthcare providers in management of chronic diseases. We propose, as case study, a project for the integration of various services for General Practitioners (GP) and Hospital Specialists (HS), accessing the Electronic Health Record (EHR), implementing the Patient Summary and managing the exchange of Chronic Care med…
Data-Centric and Multimedia Components
2011
The content of XML documents is often primarily plain text, interspersed with various headers and perhaps some lists and tables. However, there are many applications for which the content of documents is not primarily narrative in nature, but instead includes (portions of) data records that are subject to storage and computational manipulation. The latter documents are sometimes referred to as data-centric or record-like, and they rely extensively on precise descriptions of the forms of data that can appear. In this chapter we first introduce the data type definition capabilities in XML Schema. We then consider the types of data very common in traditional databases: numeric data, dates, and…
An efficient hardware implementation of MQ decoder of the JPEG2000
2014
Abstract JPEG2000 is an international standard for still images intended to overcome the shortcomings of the existing JPEG standard. Compared to JPEG image compression techniques, JPEG2000 standard has not only better not only has better compression ratios, but it also offers some exciting features. As it’s hard to meet the real-time requirement of image compression systems by software, it is necessary to implement compression system by hardware. The MQ decoder of the JPEG2000 standard is an important bottleneck for real-time applications. In order to meet the real-time requirement we propose in this paper a novel architecture for a MQ decoder with high throughput which is comparable to tha…
Pini Language and PiniTree Ontology Editor: Annotation and Verbalisation for Atomised Journalism
2020
We present a new ontology language Pini and the PiniTree ontology editor supporting it. Despite Pini language bearing lot of similarities with RDF, UML class diagrams, Property Graphs and their frontends like Google Knowledge Graph and Protege, it is a more expressive language enabling FrameNet-style natural language annotation for Atomised journalism use case.
The Possibilities of Using BCI Technology in Biomedical Engineering
2018
The paper presents capabilities of building devices dedicated for persons with heavy mobility dysfunction and indicates the role of interfaces connecting brain with computer (Brain Computer Interface, BCI). Impulses coming from closing eyes, clenching teeth, and tongue movement were proposed as optimal in controlling the applications that manage executable systems. A group of electrodes giving a strong electric signal characteristic for the activity were designated and on the basis of conducted research a proposition of a scientific project concerning building of supporting devices for persons with heavy mobility dysfunction was presented.
MCD: Overcoming the Data Download Bottleneck in Data Centers
2013
The data download problem in data centers describes the increasingly common task of coordinated loading of identical data to a large number of nodes. Data download is seen as a significant problem in exascale HPC applications. Uncoor-dinated reading from a central file server creates contention at the file server and its network interconnect. We propose and evaluation a reliable multicast based approach to solve the data download problem. The MCD system builds a logical multi-rooted tree based on the physical network topology and uses the logical view for a two-phase approach. In the first phase, the data is multicasted to all nodes. In the second phase, the logical tree is used for an effi…