scholarly journals Array databases: concepts, standards, implementations

2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Peter Baumann ◽  
Dimitar Misev ◽  
Vlad Merticariu ◽  
Bang Pham Huu

AbstractMulti-dimensional arrays (also known as raster data or gridded data) play a key role in many, if not all science and engineering domains where they typically represent spatio-temporal sensor, image, simulation output, or statistics “datacubes”. As classic database technology does not support arrays adequately, such data today are maintained mostly in silo solutions, with architectures that tend to erode and not keep up with the increasing requirements on performance and service quality. Array Database systems attempt to close this gap by providing declarative query support for flexible ad-hoc analytics on large n-D arrays, similar to what SQL offers on set-oriented data, XQuery on hierarchical data, and SPARQL and CIPHER on graph data. Today, Petascale Array Database installations exist, employing massive parallelism and distributed processing. Hence, questions arise about technology and standards available, usability, and overall maturity. Several papers have compared models and formalisms, and benchmarks have been undertaken as well, typically comparing two systems against each other. While each of these represent valuable research to the best of our knowledge there is no comprehensive survey combining model, query language, architecture, and practical usability, and performance aspects. The size of this comparison differentiates our study as well with 19 systems compared, four benchmarked to an extent and depth clearly exceeding previous papers in the field; for example, subsetting tests were designed in a way that systems cannot be tuned to specifically these queries. It is hoped that this gives a representative overview to all who want to immerse into the field as well as a clear guidance to those who need to choose the best suited datacube tool for their application. This article presents results of the Research Data Alliance (RDA) Array Database Assessment Working Group (ADA:WG), a subgroup of the Big Data Interest Group. It has elicited the state of the art in Array Databases, technically supported by IEEE GRSS and CODATA Germany, to answer the question: how can data scientists and engineers benefit from Array Database technology? As it turns out, Array Databases can offer significant advantages in terms of flexibility, functionality, extensibility, as well as performance and scalability—in total, the database approach of offering “datacubes” analysis-ready heralds a new level of service quality. Investigation shows that there is a lively ecosystem of technology with increasing uptake, and proven array analytics standards are in place. Consequently, such approaches have to be considered a serious option for datacube services in science, engineering and beyond. Tools, though, vary greatly in functionality and performance as it turns out.

2016 ◽  
Vol 4 (3) ◽  
pp. 22-37 ◽  
Author(s):  
Nayem Rahman

Scorecard-based measurement techniques are used by organizations to measure the performance of their business operations. A scorecard approach could be applied to a database system to measure performance of SQL (Structured Query Language) being executed and the extent of resources being used by SQL. In a large data warehouse, thousands of jobs run daily via batch cycles to refresh different subject areas. Simultaneously, thousands of queries by business intelligence tools and ad-hoc queries are being executed twenty-four by seven. There needs to be a controlling mechanism to make sure these batch jobs and queries are efficient and do not consume database systems resources more than optimal. The authors propose measurement of SQL query performance via a scorecard tool. The motivation behind using a scorecard tool is to make sure that the resource consumption of SQL queries is predictable and the database system environment is stable. The experimental results show that queries that pass scorecard evaluation criteria tend to utilize optimal level of database systems computing resources. These queries also show improved parallel efficiency (PE) in using computing resources (CPU, I/O and spool space) that demonstrate the usefulness of SQL scorecard.


2011 ◽  
pp. 177-212 ◽  
Author(s):  
Wenye Wang

Location modeling represents inclusive mobile objects and their relationship in space, dealing with how to describe a mobile object’s location. The goal of mobility modeling, on the other hand, is to predict or statistically estimate the movement of mobile objects. With the increasing demand for multimedia applications, location-aware services, and system capacity, many recognize that modeling and management of location and mobility is becoming critical to locating mobile objects in wireless information networks. Mobility modeling and location management strongly influence the design and performance of wireless networks in many aspects, such as routing, network planning, handoff, call admission control, and so forth. In this chapter, we present a comprehensive survey of mobility and location models, and schemes used for location-mobility management in cellular and ad hoc networks, which are discussed along with necessary, but understandable, formulation, analysis, and discussions.


Sensors ◽  
2019 ◽  
Vol 20 (1) ◽  
pp. 38 ◽  
Author(s):  
Muhammad Fahad Khan ◽  
Kok-Lim Alvin Yau ◽  
Rafidah Md Noor ◽  
Muhammad Ali Imran

Flying ad hoc network (FANET) is a self-organizing wireless network that enables inexpensive, flexible, and easy-to-deploy flying nodes, such as unmanned aerial vehicles (UAVs), to communicate among themselves in the absence of fixed network infrastructure. FANET is one of the emerging networks that has an extensive range of next-generation applications. Hence, FANET plays a significant role in achieving application-based goals. Routing enables the flying nodes to collaborate and coordinate among themselves and to establish routes to radio access infrastructure, particularly FANET base station (BS). With a longer route lifetime, the effects of link disconnections and network partitions reduce. Routing must cater to two main characteristics of FANETs that reduce the route lifetime. Firstly, the collaboration nature requires the flying nodes to exchange messages and to coordinate among themselves, causing high energy consumption. Secondly, the mobility pattern of the flying nodes is highly dynamic in a three-dimensional space and they may be spaced far apart, causing link disconnection. In this paper, we present a comprehensive survey of the limited research work of routing schemes in FANETs. Different aspects, including objectives, challenges, routing metrics, characteristics, and performance measures, are covered. Furthermore, we present open issues.


Author(s):  
Fredi Edgardo Palominos ◽  
Felisa Córdova ◽  
Claudia Durán ◽  
Bryan Nuñez

OLAP and multidimensional database technology have contributed significantly to speed up and build confidence in the effectiveness of methodologies based on the use of management indicators in decision-making, industry, production, and services. Although there are a wide variety of tools related to the OLAP approach, many implementations are performed in relational database systems (R-OLAP). So, all interrogation actions are performed through queries that must be reinterpreted in the SQL language. This translation has several consequences because SQL language is based on a mixture of relational algebra and tuple relational calculus, which conceptually responds to the logic of the relational data model, very different from the needs of the multidimensional databases. This paper presents a multidimensional query language that allows expressing multidimensional queries directly over ROLAP databases. The implementation of the multidimensional query language will be done through a middleware that is responsible for mapping the queries, hiding the translation to a layer of software not noticeable to the end-user. Currently, progress has been made in the definition of a language where through a key statement, called aggregate, it is possible to execute the typical multidimensional operators which represent an important part of the most frequent operations in this type of database.


2019 ◽  
Vol 13 (2) ◽  
pp. 122-130
Author(s):  
Dian ayunita Nugraheni nurmala Dewi

Objectives of this study were analyze fish auction participant satisfaction to auction services in TPI Morodemak, analyze attributes effect, services that fit to service quality measurement, and analyzed fish auction participants perception to performance and importance for fish auction house Morodemak services. Used descriptive method and purposive sampling with 49 respondents consists of commercial fishmongers, traditional fishmongers, purse seine owners, and boat lift net owners as fish auction participant. Satisfication measurement used Customer Satisfication Index (CSI), Importance and Performance Analysis (IPA) and gap analysis. Results from this study were value CSI 20% (0.2) indicate the auction participants dissatisfied with the services provided, IPA show there are four attributes should be develop, two elements have not been completed based on measurement requirements of service satisfaction, gap value average -0.05 means the auction participants were not satisfied with the performance of TPI services because the performance value was lower than the importance value.


2018 ◽  
Vol 2 (01) ◽  
pp. 14
Author(s):  
Eddy Supardi

The Tax Payer obidience in fulfiling their taxation obligation will be influenced a lot by the satisfaction level toward the service fiscus. The aim of this observation is to know the response of Tax Payer toward service quality through importance and performance. The population which become the object of this observation is the personal Tax Payer registered in Bogor Tax Service Office and the number of respondents taken as the sample are 100 respondents with Slovin formula. The analysis method used is descriptive analysis and importance-performance analysis.   The result of this observation will be able to be used as one of the input to Bogor Tax Service Office in improving the quality service and for the following observation, especially those who take the same object as the observation in order to improve the quality service to the Tax Payer based on the service of its working way which is felt less. Otherwise it is important for The Tax Payer, maintaining the good work or balancing the service quality based on the working way which is evaluated less important by The Taxe Payer, but has been done reasonably well or very well by The Service Office


Sensors ◽  
2021 ◽  
Vol 21 (4) ◽  
pp. 1342
Author(s):  
Borja Nogales ◽  
Miguel Silva ◽  
Ivan Vidal ◽  
Miguel Luís ◽  
Francisco Valera ◽  
...  

5G communications have become an enabler for the creation of new and more complex networking scenarios, bringing together different vertical ecosystems. Such behavior has been fostered by the network function virtualization (NFV) concept, where the orchestration and virtualization capabilities allow the possibility of dynamically supplying network resources according to its needs. Nevertheless, the integration and performance of heterogeneous network environments, each one supported by a different provider, and with specific characteristics and requirements, in a single NFV framework is not straightforward. In this work we propose an NFV-based framework capable of supporting the flexible, cost-effective deployment of vertical services, through the integration of two distinguished mobile environments and their networks: small sized unmanned aerial vehicles (SUAVs), supporting a flying ad hoc network (FANET) and vehicles, promoting a vehicular ad hoc network (VANET). In this context, a use case involving the public safety vertical will be used as an illustrative example to showcase the potential of this framework. This work also includes the technical implementation details of the framework proposed, allowing to analyse and discuss the delays on the network services deployment process. The results show that the deployment times can be significantly reduced through a distributed VNF configuration function based on the publish–subscribe model.


Author(s):  
Gaurav Chaurasia ◽  
Arthur Nieuwoudt ◽  
Alexandru-Eugen Ichim ◽  
Richard Szeliski ◽  
Alexander Sorkine-Hornung

We present an end-to-end system for real-time environment capture, 3D reconstruction, and stereoscopic view synthesis on a mobile VR headset. Our solution allows the user to use the cameras on their VR headset as their eyes to see and interact with the real world while still wearing their headset, a feature often referred to as Passthrough. The central challenge when building such a system is the choice and implementation of algorithms under the strict compute, power, and performance constraints imposed by the target user experience and mobile platform. A key contribution of this paper is a complete description of a corresponding system that performs temporally stable passthrough rendering at 72 Hz with only 200 mW power consumption on a mobile Snapdragon 835 platform. Our algorithmic contributions for enabling this performance include the computation of a coarse 3D scene proxy on the embedded video encoding hardware, followed by a depth densification and filtering step, and finally stereoscopic texturing and spatio-temporal up-sampling. We provide a detailed discussion and evaluation of the challenges we encountered, as well as algorithm and performance trade-offs in terms of compute and resulting passthrough quality.;AB@The described system is available to users as the Passthrough+ feature on Oculus Quest. We believe that by publishing the underlying system and methods, we provide valuable insights to the community on how to design and implement real-time environment sensing and rendering on heavily resource constrained hardware.


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