An Asynchronous Replication Model to Improve Data Available into a Heterogeneous System

Data replication is an important technique for high level data availability, especially applied for distributed systems. To enhance the data access and data reliability, data replication is one of the most important aspects. This paper is proposed a asynchronous replication model. This model also supports heterogeneous system which is currently a very promising system. In our proposed model the main server and replication servers are loosely coupled. Since the structure is loosely coupled and asynchronous model thus there is less dependency on each server. Moreover the proposed model is supporting heterogeneous system, so it will be highly cost minimizing solution for efficient data replication. Keywords: Data replication, Data Persistency, Asynchronous, Heterogeneous Replication

Distributed Hash Tables in P2P Network: Detection and Prevention of Threats and Vulnerability

Currently the peer-to-peer search focuses on efficient hash lookup systems which can be use in building more complex distributed systems. These system works well when their algorithms are executed in right direction but generally they don’t consider how to handle misbehaving nodes. In our paper we considers different sorts of security problems which are inherent in peer-to peer systems based on distributed hash lookup systems. We examine different types of problems that this kind of systems might face, taking examples from existing systems. Here we propose some design principles for detecting as well preventing those problems. Keywords- Distributed hash lookup systems, verifiable system invariants, verifiable key assignment, Server selection in routing

Fractal dimension of fractal functions on the real projective plane

In this article, we consider an iterated functions system on the non-Euclidean real projective plane which has a linear structure. Then, we study the fractal dimension of the associated curve as a subset of the projective space and like a set of the Euclidean space. At the end, we initiate a dual real projective iterated function system and pose an open problem

Fractal frames of functions on the rectangle

In this paper, we define fractal bases and fractal frames of L2(I   J), where I and J are real compact intervals, in order to approximate two-dimensional square-integrable maps whose domain is a rectangle, using the identification of L2(I   J) with the tensor product space L2(I) NL2(J). First, we recall the procedure of constructing a fractal perturbation of a continuous or integrable function. Then, we define fractal frames and bases of L2(I   J) composed of product of such fractal functions. We also obtain weaker families as Bessel, Riesz and Schauder sequences for the same space. Additionally, we study some properties of the tensor product of the fractal operators associated with the maps corresponding to each variable

Distributed Control of Cyber Physical System on Various Domains: A Critical Review

Cyber-Physical System (CPS) is a symbol of the fourth industrial revolution (4IR) by integrating physical and computational processes which can associate with humans in various ways. In short, the relationship between Cyber networks and the physical component is known as CPS, which is assisting to incorporate the world and influencing our ordinary life significantly. In terms of practical utilization of CPS interacting abundant difficulties. Currently, CPS is involved in modern society very vastly with many uptrend perspectives. All the new technologies by using CPS are accelerating our journey of innovation. In this paper, we have explained the research areas of 14 important domains of Cyber-Physical Systems (CPS) including aircraft transportation systems, battlefield surveillance, chemical production, energy, agriculture (food supply), healthcare, education, industrial automation, manufacturing, mobile devices, robotics, transportation, and vehicular. We also demonstrated the challenges and future direction of each paper of all domains. Almost all articles have limitations on security, data privacy, and safety. Several projects and new dimensions are mentioned where CPS is the key integration. Consequently, the researchers and academicians will be benefited to update the CPS workspace and it will help them with more research on a specific topic of CPS. 158 papers are studied in this survey as well as among these, 98 papers are directly studied with the 14 domains with challenges and future instruction which is the first survey paper as per the knowledge of authors

Developing and populating data warehouse for water quality parameters of Dhaka river system based on multidimensional data model

Developing and populating of data warehouse for water quality parameters based on multidimensional data model allows to collect, store and process ecological information of Dhaka river system and provides information support for decision making, such as selecting of water treatment technology, constructing of sewage treatment plant etc

Security Management Methods in Object-Oriented Database

Security for object-oriented databases follows the traditional lines of discretionary access control, mandatory access control, and multilevel secure database systems. Security and integrity can be implemented in the object-oriented database model. We propose extensions to the basic data model to incorporate security and integrity. Our secrecy/integrity mechanism is based on the idea access control in function granularity is one of the features of many object-oriented databases. In those systems, the users are granted rights to invoke composed functions instead of rights to invoke primitive operations. Although primitive operations are invoked inside composed functions, the users can invoke them only through the granted functions. This achieves access control in abstract operation level. Access control utilizing encapsulated functions, however, easily causes many “security flaws” through which malicious users can bypass the encapsulation and can abuse the primitive operations inside the functions. In this paper, we develop a technique to statically detect such security flaws. First, we design a framework to describe security requirements that should be satisfied. Then, we develop an algorithm that syntactically analyzes program code of the functions and determines whether given security requirements are satisfied or not. This algorithm is sound, that is, whenever there is a security flaw, it detects it