Filters








859 Hits in 4.0 sec

Skyline Queries Computation on Crowdsourced-Enabled Incomplete Database

Marwa B. Swidan, Ali A. Alwan, Sherzod Turaev, Hamidah Ibrahim, Abedallah Zaid Abualkishik, Yonis Gulzar
2020 IEEE Access  
Most importantly, the skylines derived from incomplete databases are also incomplete in which some values are missing.  ...  The issue of estimating the missing values of skylines has been discussed and examined in the database literature.  ...  estimation for the missing values in the database.  ... 
doi:10.1109/access.2020.3000664 fatcat:lt33ybyzfna5fhzqj6r37afmqa

A Model for Processing Skyline Queries in Crowd-sourced Databases

Marwa B. Swidan, Ali A. Alwan, Sherzod Turaev, Yonis Gulzar
2018 Indonesian Journal of Electrical Engineering and Computer Science  
The main idea of the proposed model is exploiting the available data in the database to estimate the missing values.  ...  Additionally, crowd-sourcing database allows performing database operators on incomplete data as human workers can be involved to provide estimated values during run-time.  ...  An accurate estimate values generator This component is responsible to generate estimated values for those skylines with incomplete data.  ... 
doi:10.11591/ijeecs.v10.i2.pp798-806 fatcat:qjowjcwlondzhbx6fismf3xtzq

Processing Skyline Queries in Incomplete Database: Issues, Challenges and Future Trends

Yonis Gulzar, Ali A. Alwan, Norsaremah Salleh, Imad Fakhri Al Shaikhli
2017 Journal of Computer Science  
Besides, we also discuss in detail the current challenges in processing skyline queries in the incomplete database and investigate the impact of incomplete data on skyline operation.  ...  This paper attempts to survey and analyze the previous works proposed to process skyline queries in the incomplete database.  ...  There is no ethical issue involved in this article.  ... 
doi:10.3844/jcssp.2017.647.658 fatcat:3kssqk36nzhwhnvumba6ngfkie

An Overview of Query Processing on Crowdsourced Databases

Marwa Swidan, Ali Alwan
2020 Basic and Applied Sciences - Scientific Journal of King Faisal University  
Crowd-sourcing is a powerful solution for finding correct answers to expensive and unanswered queries in databases, including those with uncertain and incomplete data.  ...  Crowd-sourcing database systems (CSDBs) combine the knowledge of the crowd with a relational database by using some variant of a relational database with minor changes.  ...  Also, he is working as a consultant for a regional software development company to prepare an accurate estimation for project deliverables.  ... 
doi:10.37575/b/cmp/2410 fatcat:2nt3f7ymxvfgrey5jwxbcsvep4

Crowdsourcing for Query Processing onWeb Data: A Case Study on the Skyline Operator

Kinda El Maarry, Christoph Lofi, Wolf-Tilo Balke
2015 Journal of Computing and Information Technology  
In this paper, we showcase how such optimizations can be performed for the popular skyline operator for preference queries.  ...  This is especially important for Web data which in contrast to well-maintained databases is almost always incomplete and may be distributed over a variety of sources.  ...  Surrogate with expected values (value imputation): This approach relies on various statistical means to predict the expected values of incomplete tuples, i.e. missing values are replaced by their estimated  ... 
doi:10.2498/cit.1002509 fatcat:mil7expopfbvhc3lez3grzqsie

Skyline queries in crowd-enabled databases

Christoph Lofi, Kinda El Maarry, Wolf-Tilo Balke
2013 Proceedings of the 16th International Conference on Extending Database Technology - EDBT '13  
Skyline queries are a well-established technique for database query personalization and are widely acclaimed for their intuitive query formulation mechanisms.  ...  , therefore enabling the elicitation of missing values during runtime.  ...  Whilst value imputation directly estimates missing values, distribution based imputation estimates the conditional distribution of missing values upon which the predictions will be based, e.g., in the  ... 
doi:10.1145/2452376.2452431 dblp:conf/edbt/LofiMB13 fatcat:n4yjoog4erbxreoe6smezp2uv4

Optimizing Skyline Query Processing in Incomplete Data

Yonis Gulzar, Ali A. Alwan, Sherzod Turaev
2019 IEEE Access  
This paper presents a framework called Optimized Incomplete Skyline (OIS) which utilizes a technique that simplifies the skyline process on a database with missing data and helps prune the data items before  ...  Skyline queries are used to identify superior data items in the database.  ...  Here, the database characteristics indicate whether the database is complete (no missing values exist in the database) or the database has missing values in one or more dimensions. III.  ... 
doi:10.1109/access.2019.2958202 fatcat:bqi7ldlui5gx5acso3fbwcrlki

A Rule-based Skyline Computation over a Dynamic Database

Ghazaleh Babanejad Dehaki, Hamidah Ibrahim, Fatimah Sidi, Nur Izura Udzir, Ali A. Alwan
2020 Proceedings of the 22nd International Conference on Information Integration and Web-based Applications & Services  
However, the dynamic nature of databases in which their states and/or structures change throughout their lifetime to incorporate the current and latest information of database applications, requires a  ...  Skyline query which relies on the notion of Pareto dominance filters the data items from a database by ensuring only those data items that are not worse than any others are selected as skylines.  ...  Skyline Queries in Incomplete Multidimensional Database Cited 15 times https://link-springer-com.ezproxy.um.edu.my/journal/13369 View at Publisher Missing values estimation for skylines in incomplete  ... 
doi:10.1145/3428757.3429117 fatcat:pbf3lryyofc65cdgvez5optg44

Skyline Queries Over Incomplete Data Streams (Technical Report) [article]

Weilong Ren, Xiang Lian, Kambiz Ghazinour
2019 arXiv   pre-print
In this paper, we will formalize and tackle a novel and important problem, named skyline query over incomplete data stream (Sky-iDS), which retrieves skyline objects (in the presence of missing attributes  ...  In practice, due to the malfunction of sensing devices or imperfect data collection techniques, real-world stream data may often contain missing or incomplete data attributes.  ...  In the literature, Mohamed et al. [28] re-defined the skyline operator over static incomplete database.  ... 
arXiv:1909.11224v2 fatcat:hpijx27zrvhu3n2tz2iavhcxse

CrowdSJ: Skyline-Join Query Processing of Incomplete Datasets with Crowdsourcing

Linlin Ding, Xiao Zhang, Hanlin Zhang, Liang Liu, Baoyan Song
2021 IEEE Access  
Therefore, in this paper, in order to reflect the situation more accuracy and more user-centric, we research the problem of skyline-join query over incomplete datasets with crowdsourcing, named CrowdSJ  ...  Skyline query is very useful in decision-making systems, WSN and so on. As a variation of skyline query, skyline-join query can return the results from multiple datasets.  ...  missing values of the skylines.  ... 
doi:10.1109/access.2021.3079324 fatcat:o4macaqnyzhs7gbkc4dz4vryqq

Interactive skyline queries

Jongwuk Lee, Gae-won You, Seung-won Hwang, Joachim Selke, Wolf-Tilo Balke
2012 Information Sciences  
Skyline queries with an intuitive query formulation mechanism identify the most interesting objects for incomplete user preferences.  ...  However, the applicability of skyline queries suffers from a severe drawback because incomplete user preferences often lead to an impractical skyline size.  ...  Specifically, the database system first analyzes missing knowledge based on the current skyline, and then considers preference elicitation in an interactive fashion.  ... 
doi:10.1016/j.ins.2012.04.007 fatcat:zo26bf33izcrlockkohi6kxa2q

Finding Superior Skyline Points from Incomplete Data

Rahul Bharuka, P. Sreenivasa Kumar
2013 International Conference on Management of Data  
However, skyline computation for incomplete domain, where points have missing values for some dimensions, has not received enough attention.  ...  The existing solutions for such incomplete datasets use weak pareto dominance relation which is nontransitive and cyclic. Hence, many of the desirable points are not included in the skyline.  ...  [29] proposed to convert an incomplete dataset to corresponding complete dataset by plugging in estimated values for the missing dimensional values.  ... 
dblp:conf/comad/BharukaK13 fatcat:razrz2s2wbh3pjwc47m3dwnl3q

Flexible and extensible preference evaluation in database systems

Justin J. Levandoski, Ahmed Eldawy, Mohamed F. Mokbel, Mohamed E. Khalefa
2013 ACM Transactions on Database Systems  
While numerous preference evaluation methods for databases have been proposed (e.g., skyline, top-k, k-dominance, kfrequency), the implementation of these methods at the core of a database system is a  ...  To solve this problem, this paper introduces FlexPref, a framework for extensible preference evaluation in database systems.  ...  list to fill in missing attributes.  ... 
doi:10.1145/2508020.2493268 fatcat:a3gsz3ewufd4ddusu6g7pxbipy

Understanding the meaning of a shifted sky: a general framework on extending skyline query

Zhenjie Zhang, Hua Lu, Beng Chin Ooi, Anthony K. H. Tung
2009 The VLDB journal  
Skyline queries are often used on data sets in multi-dimensional space for many decision-making applications.  ...  We also extend our analysis to data sets with missing values, and present extensive experimental results on the combinations of new dominance relationships and skyline algorithms.  ...  value of p, and estimates a concrete value for each missing value based on the known pdf on that relevant dimension.  ... 
doi:10.1007/s00778-009-0148-z fatcat:xkpf43i2fjarjf6wxeqrfywp3q

Flexible skylines, regret minimization and skyline ranking: a comparison to know how to select the right approach [article]

Vittorio Fabris
2022 arXiv   pre-print
The skyline approach makes it difficult to always retrieve an accurate result, in particular when the user has to deal with a dataset whose tuples are defined by semantically different attributes.  ...  We present a comparison between the three different operators, recalling their way of behaving and defining a guideline for the readers so that it is easier for them to decide which one, among these three  ...  Flexible Skyline As it has been pointed out before, it is difficult for the users to guess and set the right value for the weights in a scoring function.  ... 
arXiv:2201.10179v2 fatcat:lr3eoqaqhbcvdatckr3wt24cqq
« Previous Showing results 1 — 15 out of 859 results