968 resultados para Relational Model


Relevância:

100.00% 100.00%

Publicador:

Resumo:

Online business or Electronic Commerce (EC) is getting popular among customers today, as a result large number of product reviews have been posted online by the customers. This information is very valuable not only for prospective customers to make decision on buying product but also for companies to gather information of customers’ satisfaction about their products. Opinion mining is used to capture customer reviews and separated this review into subjective expressions (sentiment word) and objective expressions (no sentiment word). This paper proposes a novel, multi-dimensional model for opinion mining, which integrates customers’ characteristics and their opinion about any products. The model captures subjective expression from product reviews and transfers to fact table before representing in multi-dimensions named as customers, products, time and location. Data warehouse techniques such as OLAP and Data Cubes were used to analyze opinionated sentences. A comprehensive way to calculate customers’ orientation on products’ features and attributes are presented in this paper.

Relevância:

100.00% 100.00%

Publicador:

Relevância:

100.00% 100.00%

Publicador:

Resumo:

In this article, we describe and model the language classroom as a complex adaptive system (see Logan & Schumann, 2005). We argue that linear, categorical descriptions of classroom processes and interactions do not sufficiently explain the complex nature of classrooms, and cannot account for how classroom change occurs (or does not occur), over time. A relational model of classrooms is proposed which focuses on the relations between different elements (physical, environmental, cognitive, social) in the classroom and on how their interaction is crucial in understanding and describing classroom action.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Владимир Димитров - Целта на настоящия доклад е формалната спецификация на релационния модел на данни. Тази спецификация след това може да бъде разширена към Обектно-релационния модел на данни и към Потоците от данни.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

This article develops a relational model of institutional work and complexity. This model advances current institutional debates on institutional complexity and institutional work in three ways. First, it provides a relational and dynamic perspective on institutional complexity by explaining how constellations of logics - and their degree of internal contradiction - are constructed rather than given. Second, it refines our current understanding of agency, intentionality and effort in institutional work by demonstrating how different dimensions of agency interact dynamically in the institutional work of reconstructing institutional complexity. Third, it situates institutional work in the everyday practice of individuals coping with the institutional complexities of their work. In doing so, it reconnects the construction of institutionally complex settings to the actions and interactions of the individuals who inhabit them. © The Author(s) 2013.

Relevância:

70.00% 70.00%

Publicador:

Resumo:

The continuous changing impacts appeared in all solution understanding approaches in the projects management field (especially in the construction field of work) by adopting dynamic solution paths. The paper will define what argue to be a better relational model for project management constraints (time, cost, and scope). This new model will increase the success factors of any complex program / project. This is a qualitative research adopting a new avenue of investigation by following different approach of attributing project activities with social phenomena, and supporting phenomenon with field of observations rather than mathematical method by emerging solution from human, and ants' colonies successful practices. The results will show the correct approach of relation between the triple constraints considering the relation as multi agents system having specified communication channels based on agents locations. Information will be transferred between agents, and action would be taken based on constraint agents locations in the project structure allowing immediate changes abilities in order to overcome issues of over budget, behind schedule, and additional scope impact. This is complex adaptive system having self organizes technique, and cybernetic control. Resulted model can be used for improving existing project management methodologies.

Relevância:

70.00% 70.00%

Publicador:

Resumo:

When a computer program requires legitimate access to confidential data, the question arises whether such a program may illegally reveal sensitive information. This paper proposes a policy model to specify what information flow is permitted in a computational system. The security definition, which is based on a general notion of information lattices, allows various representations of information to be used in the enforcement of secure information flow in deterministic or nondeterministic systems. A flexible semantics-based analysis technique is presented, which uses the input-output relational model induced by an attacker's observational power, to compute the information released by the computational system. An illustrative attacker model demonstrates the use of the technique to develop a termination-sensitive analysis. The technique allows the development of various information flow analyses, parametrised by the attacker's observational power, which can be used to enforce what declassification policies.

Relevância:

70.00% 70.00%

Publicador:

Resumo:

Database systems have a user interface one of the components of which will normally be a query language which is based on a particular data model. Typically data models provide primitives to define, manipulate and query databases. Often these primitives are designed to form self-contained query languages. This thesis describes a prototype implementation of a system which allows users to specify queries against the database in a query language whose primitives are not those provided by the actual model on which the database system is based, but those provided by a different data model. The implementation chosen is the Functional Query Language Front End (FQLFE). This uses the Daplex functional data model and query language. Using FQLFE, users can specify the underlying database (based on the relational model) in terms of Daplex. Queries against this specified view can then be made in Daplex. FQLFE transforms these queries into the query language (Quel) of the underlying target database system (Ingres). The automation of part of the Daplex function definition phase is also described and its implementation discussed.

Relevância:

60.00% 60.00%

Publicador:

Resumo:

Despite being poised as a standard for data exchange for operation and maintenance data, the database heritage of the MIMOSA OSA-EAI is clearly evident from using a relational model at its core. The XML schema (XSD) definitions, which are used for communication between asset management systems, are based on the MIMOSA common relational information schema (CRIS), a relational model, and consequently, many database concepts permeate the communications layer. The adoption of a relational model leads to several deficiencies, and overlooks advances in object-oriented approach for an upcoming version of the specification, and the common conceptual object model (CCOM) sees a transition to fully utilising object-oriented features for the standard. Unified modelling language (UML) is used as a medium for documentation as well as facilitating XSD code generation. This paper details some of the decisions faced in developing the CCOM and provides a glimpse into the future of asset management and data exchange models.

Relevância:

60.00% 60.00%

Publicador:

Resumo:

Organizations are increasingly seeking stakeholder support through engagement to demonstrate their corporate social responsibility (CSR) credentials. These credentials are in turn used to support claims of legitimacy for organizational operations. This paper uses a process model of antecedents, implementation, and consequences to study the connection between engagement and CSR. CSR reports show organizations perceive engagement in CSR as both communication and activities between organizations and their stakeholders; and as a second, meta-level of communication about that engagement with stakeholders beyond those directly involved, thereby broadening the scope of organizational claims to legitimacy. Understanding what engagement is and how and why it is carried out in CSR provides a framework for understanding engagement in public relations.

Relevância:

60.00% 60.00%

Publicador:

Resumo:

本文以空值的完全语义为基础,以空值环境下基于5值(5VL)的选择运算为工具,深入研究了基于关于模型的含空值关系数据库的数据更新策略和实现算法

Relevância:

60.00% 60.00%

Publicador:

Resumo:

本文介绍了关系数据库中信息不完全性的含义及其表现,论述了关系数据库中不同范畴不完全性同时存在的可能性和必然性,并在关系模式中引入一种混合类不完全信息。为了能够表示和处理关系数据库中这种混合类不完全信息,文中最后给出了一种简化的扩展关系模型。

Relevância:

60.00% 60.00%

Publicador:

Resumo:

本文在[1]扩展关系模型中引入属性级的不完全信息空值。为适应此环境下更新操作的需要,本文对[1]中的扩展关系模型进行了进一步的扩展,并以此模型为基础讨论了空值环境下含不确定及可能信息关系数据库的更新操作的策略,给出了相应的处理算法。

Relevância:

60.00% 60.00%

Publicador:

Resumo:

In this paper,the traditional relational model is extended in order to express indefinite and maybe information. On the basis of the extended relational model.,the foundamental operations in relational algebra are defined again,and the policy and algorithm for updating relational database are given.

Relevância:

60.00% 60.00%

Publicador:

Resumo:

本文以[1]中的扩展关系模型为基础在两种元组级的不完全信息──不确定及可能信息中引入属性级的不完全信息空值,使两种不同性质的不完全信息同时出现在同一关系中。为了能够查询到不同种类及不同确定程度的信息,文中制定了这种扩展关系模型上关系的查询策略,定义了能够体现这种策略的最小关系代数运算。