relational data model definition
Tài liệu Activity 4.2: Creating a Logical Data Model ppt
Ngày tải lên :
21/12/2013, 06:16
...
Activity 4.2: Creating a Logical Data
Model
In this activity, you will use the skills learned in this module to define the
relationships within a logical data model and produce a sample ER diagram ... Activity 4.2: Creating a Logical Data Model 19
Exercise 2:
Determining Cardinality and Existence
In this exercise, you will ... activity, you will be able to:
!
Identify relationships between entities.
!
Create a logical data model.
Before You Begin
This activity will take place in small groups with a class discussion...
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Tài liệu NoSQL Database Technology: Post-relational data management for interactive software systems docx
Ngày tải lên :
19/02/2014, 12:20
... their own database
technologies. These “NoSQL” databases, each eschewing the relational data model, are a far
better match for the needs modern interactive software systems.
NOSQL DATABASE ...
Denormalizing
Before storing data in an RDBMS, a schema must be created dening precisely what data can
be stored in the database and the relationships between data elements. Data is decomposed
into ... easier and allows for rapid
changes in the data model. Of course, just about all relational database functionality is lost
in the process (though if the database is sharded, much of the functionality...
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Báo cáo khoa học: "A Flexible Stand-Off Data Model with Query Language for Multi-Level Annotation" ppt
Ngày tải lên :
08/03/2014, 04:22
... associative relations representing e.g.
coreference.
2 The Data Model
We propose a stand-off data model implemented in
XML. The basedata is stored in a simple XML file
1
The current release version ... token queries exactly one basedata element
(i.e. word) or one markable.
3.1 Query Tokens
Basedata elements can be queried by matching reg-
ular expressions. Each basedata query token con-
sists ... of the relations
of their basedata elements.
While it has become common practice to use
the stand-off mechanism to relate several annota-
tion levels to one basedata file, it is also not un-
common...
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Báo cáo khoa học: "Towards A Modular Data Model For Multi-Layer Annotated Corpora" docx
Ngày tải lên :
17/03/2014, 04:20
... exists.
2 Data models
There are three purposes data models can serve.
The first purpose is context suitability. A data
model used for this purpose must reflect as well
as possible the data the user ... low
level data storage model rather than a high level
annotation data model.
A high level query language is necessary to get a
good user acceptance and to achieve independence
from lower level data models ... anno-
tated multi-modal data. NXT is based on the NITE
Object Model (NOM) which is an extension of the
XML data model. NOM features a similar separa-
tion of tiers as the PACE-Ling data model, but is
more...
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Indexing XML Data Stored in a Relational Database pot
Ngày tải lên :
07/03/2014, 14:20
... platform for the XML data model
and serves as the basis for interoperability
between relational and XML data. Whereas
query processing on XML data shredded into one
or more relational tables ...
data between the relational and XML forms.
The XML data model, however, has characteristics
that make it very hard if not practically impossible to map
to the relational data model in the general ... single, large XML instance, it is more
natural in a relational database to store the data in tables
representing the different entities in the data model. This
yields five tables for people, open...
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APPLICATION OF THE STIRLING MODEL TO ASSESS DIVERSITY USING UIS CINEMA DATA docx
Ngày tải lên :
07/03/2014, 15:20
... stake?
Why is it important to have a clear definition of diversity? An available definition and
measure of diversity can lead to an appropriate definition of the tools needed to improve
diversity. ... diversity in the film industry based on the UNESCO
database and on an original methodology.
This section highlights some proposals for improving the database. This report stresses
the importance ... that prepare more ambitious
products.
3.2 Improvement to the initial model
i) Dealing with demand
The Stirling model focuses on the production side only, which is probably due to the...
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Báo cáo khoa học: "Intelligent Selection of Language Model Training Data" ppt
Ngày tải lên :
07/03/2014, 22:20
... language
models, for each sentence of the text
source used to produce the latter language
model. We show that this produces better
language models, trained on less data, than
both random data selection ... language model a separate feature function in
the overall translation model.
The normal practice when using multiple lan-
guages models in machine translation seems to be
to train models on as much data ... between the language model from that data
source and the desired application output by intel-
ligently selecting a subset of the available data as
language model training data. This not only pro-
duces...
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Báo cáo khoa học: "A DOM Tree Alignment Model for Mining Parallel Data from the Web" doc
Ngày tải lên :
08/03/2014, 02:21
... the DOM tree alignment model, sen-
tence alignment model, and candidate web page
pair verification model are introduced.
4 DOM Tree Alignment Model
The Document Object Model (DOM) is an appli-
cation ... web parallel data mining
scheme is presented. Three component technolo-
gies, the DOM tree alignment model, the sen-
tence aligner, and the candidate parallel page
verification model are presented ... of mined data
and increase the mining coverage and speed, this
paper proposes a new web parallel data mining
scheme. Given a pair of parallel web pages as
seeds, the Document Object Model
1
...
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Data Mining Classification: Basic Concepts, Decision Trees, and Model Evaluation Lecture Notes for Chapter 4 Introduction to Data Mining pptx
Ngày tải lên :
15/03/2014, 09:20
... the database to
gather count matrix and compute its
Gini index
–
Computationally Inefficient!
Repetition of work.
© Tan,Steinbach, Kumar Introduction to Data Mining 12
Apply Model to Test Data
Refund
MarSt
TaxInc
YES
NO
NO
NO
Yes ... Tan,Steinbach, Kumar Introduction to Data Mining 3
Illustrating Classification Task
© Tan,Steinbach, Kumar Introduction to Data Mining 13
Apply Model to Test Data
Refund
MarSt
TaxInc
YES
NO
NO
NO
Yes ... Attributes
Training Data
Model: Decision Tree
© Tan,Steinbach, Kumar Introduction to Data Mining 8
Decision Tree Classification Task
Decision
Tree
© Tan,Steinbach, Kumar Introduction to Data Mining...
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Báo cáo " On the detection of gross errors in digital terrain model source data " pdf
Ngày tải lên :
22/03/2014, 12:20
... Basedonthetestresults,theauthorshavemadeconclusionsaboutthereliability
andeffectivenessofthemethodfordetectinggrosserrorsinDTMsource data.
Keywords:Digitalterrain model (DTM);
DTMsource data; Grosserrordetection;Interpolation.
1.Introduction
*
Sinceitsorigin inthe late 1950s,the Digital
Terrain Model ... in DTM source
data can be detected by comparing the
measured height of a DTM data point with an
estimated height
by interpolation from
neighboring data points. This ...
Onthedetectionofgrosserrors
indigitalterrain model source data
TranQuocBinh*
CollegeofScience,VNU
Received10October2007;receivedinrevisedform03December2007
Abstract. Nowadays, digital terrain models (DTM)...
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Báo cáo " Calibration and verification of a hydrological model using event data " ppt
Ngày tải lên :
22/03/2014, 12:20
... evaporation data as
input for the model. The daily evaporation data
at Khe Sanh station were used as inputs for the
model. For the model calibration and
verification, discharge data is required. ... The rainfall-runoff model was adopted
in this study is MIKE-NAM model. There are
nine main parameters needed to calibrate and
verify in this model. Data required by the model
include rainfall, ... (event)
data. The common way is using the continuous
simulation with the long time series data.
Compared with the continuous long time series
of data, calibration using the event data is more...
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Báo cáo khoa học: Systems biology: model based evaluation and comparison of potential explanations for given biological data pot
Ngày tải lên :
23/03/2014, 06:20
... both models, when the
data have been generated under the assumption that
model 2 is correct. As would be expected, model 1 is
always fitting the data well (i.e. there is a low cost)
when model ... referred to as test data [15].
Ideally, one would therefore divide the data set into
three separate parts: estimation data, validation data
and test data (Fig. 8). Note that the test data are differ-
ent ... residuals) for both the models, when the
data have been generated under the assumption that
model 1 is correct, and when both models have been
fitted to each generated data set. Likewise, the...
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