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Error propagation in distributed databases

O. Haase, A. Henrich
1995 Proceedings of the fourth international conference on Information and knowledge management - CIKM '95  
Furthermore, the result of a query in a distributed database system must be regarded to be potentially vague.  ...  This means, that appropriate rules for propagation and minimization of errors induced by inaccessibility are needed.  ...  On the other hand, adequate error propagation rules have to be used that keep the error as small as possible during query processing.  ... 
doi:10.1145/221270.221650 dblp:conf/cikm/HaaseH95 fatcat:fg525su4sra6fczoroleelt5c4

On the propagation of errors in the size of join results

Yannis E. Ioannidis, Stavros Christodoulakis
1991 SIGMOD record  
Query optimizers of current relational database systems tivated by their importance in query optimization and their sensitivity to error propagation. 268 We are aware of no work in the area of error propagation  ...  in the context of database query optimization.  ...  Assuming that the Zipf distribution with .z = O is used as the database approximation, the average error in each relation is zero.  ... 
doi:10.1145/119995.115835 fatcat:vlvrelr2fjd6xn2yj4zpscr4o4

On the propagation of errors in the size of join results

Yannis E. Ioannidis, Stavros Christodoulakis
1991 Proceedings of the 1991 ACM SIGMOD international conference on Management of data - SIGMOD '91  
Query optimizers of current relational database systems tivated by their importance in query optimization and their sensitivity to error propagation. 268 We are aware of no work in the area of error propagation  ...  in the context of database query optimization.  ...  Assuming that the Zipf distribution with .z = O is used as the database approximation, the average error in each relation is zero.  ... 
doi:10.1145/115790.115835 dblp:conf/sigmod/IoannidisC91 fatcat:nveqae6zencavp4gec53ltfcim

Towards Unified Dependability Modeling and Analysis

András Pataricza, Ferenc Györ
2004 Architektur von Rechensystemen  
Despite the fact of the existence of a unified concept and terminology of dependability notions and mechanisms, little convergence is observable between the specific fields in dependability engineering  ...  In dependability analysis both kinds of errors may share the same propagation mechanism with slightly differing propagation paths.  ...  The description of the error propagation can be done by using the same association rules as in the case of hardware errors.  ... 
dblp:conf/arcs/PatariczaG04 fatcat:6r6x53qvwzfwnao2kr76g42lo4

Page 337 of American Society of Civil Engineers. Collected Journals Vol. 119, Issue 3 [page]

1993 American Society of Civil Engineers. Collected Journals  
During database development, choice of cell size can now be related to consequent error in the hydrologic model thus answering the questions: 1.  ...  Any error analysis that does not explicitly consider the ultimate conse- quences (i.e., in this application, the error propagated in the simulation of direct surface runoff) is incomplete and of little  ... 

FEA-Based Ultrasonic Focusing Method in Anisotropic Media for Phased Array Systems

Seongin Moon, To Kang, Soonwoo Han, Kyung-Mo Kim, Hyung-Ha Jin, Sung-Woo Kim, Munsung Kim, Hyunil Seo
2021 Applied Sciences  
The wave propagation database was constructed using FEA considering the grain orientation distribution and the anisotropic elastic constants in the welds.  ...  The distribution of the grain orientation in the welds influences the ultrasonic wave velocity and ultrasonic wave propagation paths.  ...  nondestructive testing in sites, the information or database of the grain orientation distribution and the anisotropic elastic constants should be given in advance.  ... 
doi:10.3390/app11198888 fatcat:vw23zbbtujdlfk4yffdqmsx2qy

A Review On Accuracy and Uncertainty of Spatial Data and Analyses with special reference to Urban and Hydrological Modelling

A.A Devendran, G. Lakshmanan
2014 ISPRS Annals of the Photogrammetry, Remote Sensing and Spatial Information Sciences  
Identification of the sources of these uncertainties and the ways in which they operate in GIS based representations become crucial in any spatial data representation and geospatial analysis applied to  ...  Uncertainty in the geographic representation of the real world arises as these representations are incomplete.  ...  Though there are numerous researches on the topic of error in spatial databases, there is still a lack of proper tool for handling the errors in a spatial database.  ... 
doi:10.5194/isprsannals-ii-8-171-2014 fatcat:23saxr4lsbfsrhvobmsteffuqq

An Analysis of Impact Factors for Positioning Performance in WLAN Fingerprinting Systems Using Ishikawa Diagrams and a Simulation Platform

Keqiang Liu, Yunjia Wang, Lixin Lin, Guoliang Chen
2017 Mobile Information Systems  
It takes five nonalgorithm controllable factors including APs density, APs distribution, radio signal propagating attenuation factor, radio signal propagating noise, and RPs density into consideration  ...  The results indicate that the high APs density, signal propagating attenuation factor, and RPs density, with the low signal propagating noise level, are favorable to better performance, while APs distribution  ...  Acknowledgments The research work presented in this paper is partly supported by China National Key Research and Development Program  ... 
doi:10.1155/2017/8294248 fatcat:hrxf6puxnzdn3bxibtbej72k2y

Measurement-Based Spectrum Database for Flexible Spectrum Management

Koya SATO, Masayuki KITAMURA, Kei INAGE, Takeo FUJII
2015 IEICE transactions on communications  
In the current design of TV white space spectrum databases, a propagation model is utilized to determine the spectrum availability.  ...  In the proposed database, actual measurements of radio signals are used to estimate radio information regarding PUs.  ...  Comparison with a Propagation Model To clarify the probabilistic error performances, we evaluated the cumulative distribution function (CDF) of the radio environment estimation error.  ... 
doi:10.1587/transcom.e98.b.2004 fatcat:jraaaqwayveyfajd63inpwklby

Inaccurate spectrum databases?

Tan Zhang, Suman Banerjee
2013 Proceedings of the Twelfth ACM Workshop on Hot Topics in Networks - HotNets-XII  
In this paper, we first show that such spectrum databases (that depend solely on propagation models as per guidelines of the FCC in the USA) can be quite inaccurate leading to under-utilization of spectrum  ...  useful "anchor points" to enhance existing propagation models.  ...  Acknowledgments We thank Ning Leng for providing various comments that helped us improve some of the techniques developed in this paper.  ... 
doi:10.1145/2535771.2535793 dblp:conf/hotnets/ZhangB13 fatcat:alnkmo42tfawjer62t4joatgum

Bootstrapping the statistical uncertainties of NN scattering data

R. Navarro Pérez, J.E. Amaro, E. Ruiz Arriola
2014 Physics Letters B  
We compare the results of the bootstrap, with 1020 statistically generated samples of the full database, with the standard covariance matrix method of error propagation.  ...  No significant differences in scattering observables and phase shifts are found. This suggests alternative strategies for propagating errors of nuclear forces in nuclear structure calculations.  ...  In our previous works the covariance matrix method was used to propagate errors.  ... 
doi:10.1016/j.physletb.2014.09.035 fatcat:6m5svmkfzfgxpooztzbn7gkpg4

Efficient Numerical Error Bounding for Replicated Network Services

Haifeng Yu, Amin Vahdat
2000 Very Large Data Bases Conference  
We also discuss two optimizations that reduce the space and computational overheads in the algorithms.  ...  Target distributed services include replicated stock quotes services, online auctions, distributed sensor systems, wide-area r esource a c c ounting and load balancing for replicated servers.  ...  Bounding numerical error in a replicated database is closely related to maintaining integrity constraints in distributed databases.  ... 
dblp:conf/vldb/YuV00 fatcat:6tbq2mh4ufbaveizb2ira7chz4

Fingerprinting Localization Method Based on TOA and Particle Filtering for Mines

Boming Song, Shen Zhang, Jia Long, Qingsong Hu
2017 Mathematical Problems in Engineering  
In order to improve positioning accuracy, the NLOS error must be suppressed by an optimization algorithm.  ...  The most significant factor is the non-line of sight (NLOS) propagation error of the localization signal between the access point (AP) and the target node (Tag).  ...  Figure 6 : 6 Cumulative distribution functions of errors of the four algorithms under different conditions. (a) Cumulative error distribution of four algorithms under line corridor LOS condition.  ... 
doi:10.1155/2017/3215978 fatcat:iurmggxo3bgbpmdm2larqhzh64

Dense and Sparse Reconstruction Error Based Saliency Descriptor

Huchuan Lu, Xiaohui Li, Lihe Zhang, Xiang Ruan, Ming-Hsuan Yang
2016 IEEE Transactions on Image Processing  
databases.  ...  Second, the reconstruction errors are propagated based on the contexts obtained from K -means clustering.  ...  the effectiveness of the context-based error propagation in this work.  ... 
doi:10.1109/tip.2016.2524198 pmid:26915102 fatcat:2as3rulhana4xaf3up7b4dez2e

Optimal histograms for limiting worst-case error propagation in the size of join results

Yannis E. Ioannidis, Stavros Christodoulakis
1993 ACM Transactions on Database Systems  
Even small errors in the individual relations propagate in the query result growing at an exponential rate and generating a final error that very quickly ACM Transactions on Database Systems  ...  Thus, we concentrate on errors that arise from aggregating the frequency distributions and not on ones that arise from delaying the propagation of database updates to the histogram.  ... 
doi:10.1145/169725.169708 fatcat:z3hwyfmbp5ce3kozzckfbzvp3a
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