Development of an Assertion Model of Integrity Constraints in Object-Oriented Databases

Object-Oriented Databases (OODBs) have been designed to support large and complex programming projects. The data accuracy, consistency, and integrity in OODBs are extremely important for developers and users. Checking the integrity constraints in OODBs is a fundamental problem in database design. Existing OODB Management Systems (OODBMSs) lack to a capability of an ad-hoc declarative specification of enforcing and maintaining integrity constraints that are appeared among attributes in association, composition, and inheritance hierarchies' relationships. A critical problem in the existing OODBs is that they cannot support User-Defmed Constraints (UDCs) that can be defmed in classes with composition (logical or physical composition) and inherence (single or mUltiple inheritance) hierarchies. Integrity constraints in the current OODBMSs are maintained either by disallowing and rolling back transaction or modifying operations that may produce a violation. The constraints must be maintained in the backward direction along the class composition hierarchy as well as in the forward direction. In this work an Assertion Model of Integrity Constraints (AMIC) is proposed. The AMIC keeps the derivation path along with the attributes' relationships that are derived from association, composition, and inheritance hierarchies. The AMIC techniques are designed to implement the needed functions that are collecting the attributes' relationships and checking the integrity constraints. Moreover, AMIC keeps UDCs with their relationships in both single classes and multilevel classes (intra-class and inter-class). Furthermore, the AMIC can maintain constraints in a single object and a set of distributed objects (intra-object and inter-object). Therefore, this makes the new model extendable and can be integrated with any existing constraints' service. A new technique called Detection Method (DM) isdesigned to check the Object Meta Data (OMD) to detect the constraints violation before it occurs. The AMIC is designed for both Centralized Integrity Maintenance (CIM) and Application-Oriented Integrity Maintenance (AOIM). The AMIC can also enforce and maintain structural and logical integrity constraints, in addition to enforce and maintain redundant, inconsistent, and duplicate constraints

A novel adaptive schema to facilitates playback switching technique for video delivery in dense LTE cellular heterogeneous network environments

The services of the Video on Demand (VoD) are currently based on the developments of the technology of the digital video and the network’s high speed. The files of the video are retrieved from many viewers according to the permission, which is given by VoD services. The remote VoD servers conduct this access. A server permits the user to choose videos anywhere/anytime in order to enjoy a unified control of the video playback. In this paper, a novel adaptive method is produced in order to deliver various facilities of the VoD to all mobile nodes that are moving within several networks. This process is performed via mobility modules within the produced method since it applies a seamless playback technique for retrieving the facilities of the VoD through environments of heterogeneous networks. The main components comprise two servers, which are named as the GMF and the LMF. The performance of the simulation is tested for checking clients’ movements through different networks with different sizes and speeds, which are buffered in the storage. It is found to be proven from the results that the handoff latency has various types of rapidity. The method applies smooth connections and delivers various facilities of the VoD. Meantime, the mobile device transfers through different networks. This implies that the system transports video segments easily without encountering any notable effects.In the experimental analysis for the Slow movements mobile node handoff latency (8 Km/hour or 4 m/s) ,the mobile device’s speed reaches 4m/s, the delay time ranges from 1 to 1.2 seconds in the proposed system, while the MobiVoD system ranges from 1.1 to 1.5. In the proposed technique reaches 1.1026 seconds forming the required time of a mobile device that is switching from a single network to its adjacent one. while the handoff termination average in the MobiVoD reaches 1.3098 seconds. Medium movement mobile node handoff latency (21 Km/ hour or 8 m/s) The average handoff time for the proposed system reaches 1.1057 seconds where this implies that this technique can seamlessly provide several segments of a video segments regardless of any encountered problems. while the average handoff time for the MobiVoD reaches 1.53006623 seconds. Furthermore, Fast movement mobile node handoff latency (390 Km/ hour or 20 m/s). The average time latency of the proposed technique reaches 1.0964 seconds, while the MobiVoD System reaches to 1.668225 seconds

Cellular Harmony Search for Optimization Problems

Structured population in evolutionary algorithms (EAs) is an important research track where an individual only interacts with its neighboring individuals in the breeding step. The main rationale behind this is to provide a high level of diversity to overcome the genetic drift. Cellular automata concepts have been embedded to the process of EA in order to provide a decentralized method in order to preserve the population structure. Harmony search (HS) is a recent EA that considers the whole individuals in the breeding step. In this paper, the cellular automata concepts are embedded into the HS algorithm to come up with a new version called cellular harmony search (cHS). In cHS, the population is arranged as a two-dimensional toroidal grid, where each individual in the grid is a cell and only interacts with its neighbors.Thememory consideration and population update aremodified according to cellular EA theory. The experimental results using benchmark functions show that embedding the cellular automata concepts with HS processes directly affects the performance. Finally, a parameter sensitivity analysis of the cHS variation is analyzed and a comparative evaluation shows the success of cHS

An assertion model for controlling integrity constraints in an object-oriented database

The existing object-oriented databases cannot properly support certain constraints that are specified on a set of classes that form a class composition hierarchy. Checking the integrity constraints in databases is a fundamental problem in database design. In this paper, a model called Assertion Model for Integrity Constraints (AMIC) is proposed to ease the process of detecting the integrity constraints in an object-oriented database system. The model accepts user-defined constraints, and has efficient techniques that permit checking both the constraints in one class and the constraints between classes. AMIC proposes a method to gather the constraints and identifies the relationships among them. Also a new method is added to check the status of violation of the relations in object-oriented database

A special library for supporting Jawi fonts in BGI mode

This paper introduces a method of writing Jawi script in Borland graphic mode (BGI); something that is not handled effectively with modern computer systems. The encoding algorithm of this method works by spanning the keyboard keys sequentially from left to right and top to bottom and outputting a numerical value for each key on the keyboard so that each key on the keyboard has a numerical code value. Special drawing functions are designed to draw the different Jawi letters. A Set is used to store the value (shape) of each letter including the letters that fall in the beginning, middle, and end of words as the letters in Jawi change their appearance depending on their position in the word. All the sets and the procedures that correspond to the Jawi letters are stored in one library file. This writing method was tested and it achieved a good, easy, and relatively speedy typing

An efficient OODB model for ensuring the integrity of user-defined constraints

In this paper, a new structural model is proposed to ease the checking of the integrity constraints in an object-oriented database system. The structure accepts declarative global specification of constraints including user-defined p ]constraint, and an efficient representation that permits localized constraints checking. A new method called “Detection” is added to the structure to check the status of violation of the relations in an object-oriented database. The new approach is demonstrated using ALICE rule. The notion of the constraints is used to define the connectivity between objects required for the valid expression of constraint and rule conditions. The event in Integration Rules (IRules) that defines the active behavior of an application specifies an operation to be monitored, such as modifying a data value. The semantic analysis process applies a concept known as object-centered conditions during the compilation of ALICE rules to detect semantically incorrect rules at compile time

Enforcing Integrity for Redundant and Contradiction Constraints in OODBs

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Restructuring object-oriented database model to ease checking the integrity constraints

In this paper, a new structural model is proposed to ease the checking of the integrity constraints in an object-oriented database system. The structure accepts declarative global specification of constraints including user-defined constraint, and an efficient representation that permits localized constraints checking. A new method called "detection" is added to the structure to check the status of violation of the relations in an object-oriented database. The new approach is demonstrated using ALICE rule. The notion of the constraints is used to define the connectivity between objects required for the valid expression of constraint and rule conditions. The event in an event-condition-action (ECA) rule that defines the active behavior of an application specifies an operation to be monitored, such as modifying a data value. The semantic analysis process applies a concept known as object-centered conditions during the compilation of ALICE rules to detect semantically incorrect rules at compile time

Designing a New Assertion Constraints Model for Mobile Databases

In this paper a new assertion constraint model is proposed and implemented. The model is designed to enforce and maintain the integrity constraints in mobile database and object data model environments. It has an object assertion model for integrity constraints which it is used to create classes and collect attributes and their constraints that are derived from multiple composition or inheritance hierarchies. Also it has a compile-time model which keeps the derivation path along with the attributesâ?? relationships. Furthermore, the run-time model enforces integrity constraints, enforcing the logical integrity constraints during the run-time. And a new technique is designed to check the object metadata to detect the object violation before it occurs. However, the model is implemented and tested over set of definitions that check attribute values validity and objects for object-oriented and mobile databases