Distributed system is a collection of independent systems which can communicate with each other by transferring massages. There are some major issues in distributed systems but we focus in this paper on fault tolerance. It is the system’s ability to work in the condition when there occur any type of some fault in the system, like failure in communication, hardware or resources. It is a very important issue in distributed system, in this paper we present a survey of different types of fault tolerance techniques and their comparison.
Web security issues remain a major challenge with numerous security concerns, Distributed Denial of Service Attack (DDos) leads among these. It was evolved from DOS and its main purpose is to consume large amount of server resources so that the server cannot provide service to normal users. Attackers usually gain access to large number of computers by exploiting the vulnerabilities to set up attack armies (i.e., Botnets). This paper will review and analyse different existing DDoS detecting techniques against different parameters, and propose a new hybrid architecture for the defence mechanism of DDoS attack.
Precision viticulture is a specialization of precision agriculture techniques applied to viticulture. Precision agriculture is the use of information system technologies applied to agricultural production. Some of the applicable technologies are; Wireless Sensor Networks (WSN), Global Positioning Systems (GPS), spectroscopy analysis of Near-Infrared (NIR), Geographic Information Systems (GIS). These systems provide means of observation, evaluation and control of agricultural activities. The farmers demand assistant systems to perform actions for saving time and avoiding risks. There are studies of maps crops and mesh-sampling techniques to predict the harvest volume in a vineyard with a certain varieties of grapes. The prediction is based on a previous study of crops over a period of three to four years. Along these three or four years a large volume of samples is taken to study several parameters. In this application area is where the wireless sensor networks technologies would have high incidence. In this context we intend to analyse, at first place, the specific characteristics of the operational environment of a vineyard. Second, we will analyse the most appropriate architecture for a sensor network in this environment. Application of wireless sensor networks technology can take many forms depending of environment, and implementation objectives. In this paper we discuss about the best procedure for deployment and the optimal topology of a wireless sensor network for viticulture.
his project is part of the FlowNet initiative.
FlowNet aims at providing Internet freedom and free flow
information through socially informed, censor resistant online
social networks. My contribution for FLowNet is in devel-
oping an Android application, SecurePost. The requirement
for SecurePost is two-fold. First, the system should facilitate
secure, anonymous, group communication within a closed
group of trusted members. Second, the general public on the
Internet viewing this content, should be able to verify that the
content was generated only by the said closed group of trusted
members. The system consists of an Android client application,
a proxy server and a browser-plugin. The OSNs supported by
this system are Twitter and Facebook.
This research paper aims at exploiting efficient ways of implementing the N-Body problem. The N-Body problem, in the field of physics, predicts the movements and planets and their gravitational interactions. In this paper, the efficient execution of heavy computational work through usage of different cores in CPU and GPU is looked into; achieved by integrating the OpenMP parallelization API and the Nvidia CUDA into the code. The paper also aims at performance analysis of various algorithms used to solve the same problem. This research not only aids as an alternative to complex simulations but also for bigger data that requires work distribution and computationally expensive procedures.
No presente trabalho vamos abordar o Efeito Hall discutindo experimentos realizados afim de estimar o valores do Coeficiente Hall de dois metais,o cobre e o zinco.Com o objetivo de compará-los com o da literatura.
This paper is describing a short view on the given case – You are in a modern national state where you have the democratic power to suggest/ put forward that “democracy and equality”, OR “democracy and freedom” are the highest values and norms in your society (the group chooses which of the two alternatives you want to answer on). What would your arguments and examples be to people of your country?