Neural Network Basics An Artificial Neural Network (ANN) is an information processing paradigm that is inspired by the way biological nervous systems, such as the brain, process information. The key element of this paradigm is the novel structure of the information processing system. It is composed of a large number of highly interconnected processing elements (neurons) working in unison to solve specific problems. ANNs, like people, learn by example. An ANN is configured for a specific application, such as pattern recognition or data classification, through a learning process. Learning in biological systems involves adjustments to the synaptic connections that exist between the neurons. This is true of ANNs as well. Neural Network Definition Work on artificial neural networks, commonly referred to as “neural networks,” has been motivated right from its inception by the recognition that the human brain computes in an entirely different way from the conventional digital computer. The brain is a highly complex, nonlinear, and parallel computer (information-processing system). It has the capability to organize its structural constituents, known as neurons, so as to perform certain computations (e.g., pattern recognition, perception, and motor control) many times faster than the fastest digital computer in existence today. Consider, for example,…

Hidden Markov Model (HMM) The Hidden Markov Model (HMM) is a powerful statistical tool for modeling generative sequences that can be characterized by an underlying process generating an observable sequence. A hidden Markov model is a doubly stochastic process, with an underlying stochastic process that is not observable (hence the word hidden), but can be observed through another stochastic process that produces the sequence of observations. The hidden process consists of a set of states connected to each other by transitions with probabilities, while the observed process consists of a set of outputs or observations, each of which may be emitted by each state according to some probability density function (pdf). Depending on the nature of this pdf, several HMM classes can be distinguished. If the observations are naturally discrete or quantized using vector quantization. The Hidden Markov Model is a finite set of states, each of which is associated with a (generally multidimensional) probability distribution Transitions among the states are governed by a set of probabilities called transition probabilities. In a particular state an outcome or observation can be generated, according to the associated probability distribution. It is only the outcome, not the state visible to an external observer…

A wireless ad-hoc network is temporarily set network by wireless mobile computers moving arbitrary in the place that have no fixed infrastructure and all of the transmission links are established through wireless medium. MANETs are a kind of wireless ad-hoc network. Each node in a MANET is free to move independently in any direction leads to changing its links to other nodes frequently. Each node operates as an end system and also as a router to forward packets. The primary challenge in building a MANET is equipping each node to continuously maintain the information required to properly route traffic. Wireless ad-hoc network is promising in solving many challenging real-world problems like military field operation, communication in emergency response system and oil drilling and mining operation. Wireless mobile ad-hoc networks are vulnerable to many security attacks because of shared channel, insecure operating environment, lack of central authority, limited resource availability, dynamically changing network topology, resource constraints. MANET’s open issues are like security problem, finite transmission bandwidth, abusive broadcasting messages, reliable data delivery, dynamic link establishment and restricted hardware caused processing capabilities emerges into new horizon of different research areas. Wormhole Attack In MANETs, each node communicates directly with its neighboring nodes…

Mobile Ad-hoc Network(MANET) Attack Wireless networks can be basically either infrastructure based networks or infrastructure less networks. The infrastructure based networks uses fixed base stations, which are responsible for coordinating communication between the mobile hosts (nodes). The ad hoc networks falls under the class of infrastructure less networks, where the mobile nodes communicate with each other without any fixed infrastructure between them. An ad hoc network is a collection of nodes that do not rely on a predefined infrastructure to keep the network connected. So the functioning of Ad-hoc networks is dependent on the trust and co-operation between nodes. Nodes help each other in conveying information about the topology of the network and share the responsibility of managing the network. Hence in addition to acting as hosts, each mobile node does the function of routing and relaying messages for other mobile nodes. Black-hole Attack Security in a MANET is an essential component for basic network functions like packet forwarding and routing. Before we survey the solutions that can help secure the mobile ad hoc network, we think it necessary to find out how we can judge if a mobile ad hoc network is secure or not, or in other words,…

Decision Tree Overview In data mining techniques two kinds of basic learning processes are available namely supervised and unsupervised. when we talk about the supervised learning techniques the decision tree learning is one of the most essential technique of classification and prediction. A number of different kinds of decision tree algorithms are available i.e. ID3, C4.5, C5.0, CART, SLIQ and others. All these algorithms the used to generate the transparent data models. these data models can be evaluated using the paper and pencil. therefore that is an effective data modeling technique. Applications of Decision Trees Application of Decision Tree Algorithm in Healthcare Operations [1]: the decision trees are used to visualize the data patterns in form of tree data structure. that help to also prepare the relationship among the attributes and the final class labels. thus the patient’s different health attributes can help to understand the symptoms and possibility by comparing the historical data available with the similar attributes. Manufacturing and Production: in a large production based industries where the regulation of production and planning is required. the decision tree models helps for understanding the amount of production, time of production and other scenarios. that can be evaluated using the past scenarios of…

ID3 Decision Tree Overview Engineered by Ross Quinlan the ID3 is a straightforward decision tree learning algorithm. The main concept of this algorithm is construction of the decision tree through implementing a top-down, greedy search by the provided sets for testing every attribute at each node of decision. With the aim of selecting the attribute which is most useful to classify a provided set of data, a metric is introduced named as Information Gain [1]. To acquire the finest way for classification of learning set, one requires to act for minimizing the fired question (i.e. to minimize depth of the tree). Hence, some functions are needed that is capable of determine which questions will offer the generally unbiased splitting. One such function is information gain metric. Entropy In order to define information gain exactly, we require discussing entropy first. Let’s assume, without loss of simplification, that the resultant decision tree classifies instances into two categories, we’ll call them \( [ P_{positive} ] and [ N_{negative} ] \) Given a set S, containing these positive and negative targets, the entropy of S related to this Boolean classification is: \( [ P_{positive} ] \): proportion of positive examples in S \( [ N_{negative} ]…

k Nearest Neighbor (KNN): introduction The necessity of data mining techniques has emerged quite immensely nowadays due to massive increase in data. Data mining is the process of extracting patterns and mining knowledge from data. K nearest neighbors is a simple algorithm that stores all available cases and classifies new cases based on a similarity measure (e.g., distance functions). KNN has been used in statistical estimation and pattern recognition already in the beginning of 1970’s as a non-parametric technique. The model for KNN is the entire training dataset. When a prediction is required for a unseen data instance, the KNN algorithm will search through the training dataset for the k-most similar instances. The prediction attribute of the most similar instances is summarized and returned as the prediction for the unseen instance. Nearest neighbor classifiers is a lazy learner’s method and is based on learning by analogy. It is a supervised classification technique which is used widely. Unlike the previously described methods the nearest neighbor method waits until the last minute before doing any model construction on a given tuple. In this method the training tuples are represented in N-dimensional space. When given an unknown tuple, k-nearest neighbor classifier searches the k…

Decision Tree:Overview in different kinds of supervised data mining techniques the decision trees are one of the most popular classification and prediction technique. basically the training data samples are organized in form of tree data structure. where the nodes of tree shows the attributes of the data set and edges can be used for demonstrating the values of these attributes. additionally the leaf node of the tree contains the decisions of the classifier. example the decision tree as given in figure 1. Figure 1 decision tree example in the above given figure the decision tree model is demonstrated which contains decisions in terms of yes or no at the leaf nodes. similarly the humidity, outlook and wind are the attributes which are available in data set. additionally the relevant attribute attribute values that are frequently occurred during the evaluation of patterns. sometimes these trees can also used as the IF THEN ELSE rules. from the above given example a rule can be defined as: IF (Outlook = sun & Humidity = normal) then decision = yes Advantages the following are the key advantages of any decision tree: Decision tree are simple to understand and construct even after a brief exploration….

Web recommendation system: Introduction The term recommendation is used for describing the suggestions of a particular product or service. therefore the web recommendation systems are a essential part of e-commerce applications. The users who search about some kinds of product or services the recommendation systems helps them by suggesting the most appropriate product or services. In most of the cases the web based recommendation systems are developed using the web usage mining and content mining techniques. In this context using this concept a number of applications are created. The recommendations systems can be described in three major categories. There is an extensive class of Web applications that involve predicting user responses to options. Such a facility is called a recommendation system. However, to bring the problem into focus, two good examples of recommendation systems are [1]: Offering news articles to on-line newspaper readers, based on a prediction of reader interests. Offering customers of on-line retailer suggestions about what they might like to buy, based on their past history of purchases and/or product searches. Recommendation systems use a number of different technologies. That can be classify these systems into two broad groups Content-based systems examine properties of the items recommended. For instance, if…

Fuzzy C-means: Overview the fuzzy c-means algorithm is one of the most popular clustering technique in data mining. that technique enable the data objects to be available in more than one cluster at the time. therefore that technique can be used for other clustering technique implementations. that is also a unsupervised technique of data mining. that technique directly input the data samples as input and produces the clusters of data according to user requirements. Functional Overview basically that technique is works on the basis of optimization of the objective function. that helps to improve the cluster membership from the different clusters available. Clustering is a mathematical tool that attempts to discover structures or certain patterns in a dataset, where the objects inside each cluster show a certain degree of similarity. It can be achieved by various algorithms that differ significantly in their notion of what constitutes a cluster and how to efficiently find them. Cluster analysis is not an automatic task, but an iterative process of knowledge discovery or interactive multi-objective optimization. It will often necessary to modify pre-processing and parameter until the result achieves the desired properties. Fuzzy C-Means Clustering Fuzzy clustering is a powerful unsupervised method for the…