Aggregation delay is the minimum number of time slots required to aggregate data along the edges of a data gathering tree (DG tree) spanning all the nodes in a wireless sensor network (WSN). We propose a benchmarking algorithm to determine the minimum possible aggregation delay for DG trees in a WSN. We assume the availability of a sufficient number of unique CDMA (Code Division Multiple Access...

Wireless sensor network (WSN) open up new application area such as intelligent environmental and structural monitoring. One of the major challenges in WSN lies in the constraint energy and computation resource available in the sensor nodes. This paper deals with minimizing the energy resource of the wireless sensor nodes and maximizing its life time. When an event is detected in a particular ar...

The high-level contribution of this paper is a simulation-based comparison of two contrasting categories (minimum node size vs. stability) of connected dominating sets for mobile ad hoc networks. We pick the maximum density-based CDS (MaxD-CDS) and Node ID-based CDS (ID-CDS) to be representatives of the minimum node size-based CDS algorithms; the minimum velocity-based CDS (MinV-CDS) and the no...

among numerous np-hard problems, the traveling salesman problem (tsp) has been one of the most explored, yet unknown one. even a minor modification changes the problem’s status, calling for a different solution. the generalized traveling salesman problem (gtsp)expands the tsp to a much more complicated form, replacing single nodes with a group or cluster of nodes, where the objective is to fi...

AIMS To determine the minimum number of lymph nodes needed in an axillary lymph node dissection (ALND) specimen to be confident that the axilla is free from metastases. METHODS The Edinburgh Breast Unit selects patients with large and high grade tumours for ALND; 609 consecutive ALNDs performed between October 1999 and December 2002 were reviewed. Full data about the underlying invasive breas...

Intruders often combine exploits against multiple vulnerabilities in order to break into the system. Each attack scenario is a sequence of exploits launched by an intruder that leads to an undesirable state such as access to a database, service disruption, etc. The collection of possible attack scenarios in a computer network can be represented by a directed graph, called network attack gra...

Broadcasting is a common and basic operation used to support various network protocols in wireless networks. To achieve energy-efficient broadcasting is especially important for ad hoc wireless sensor networks because sensors are generally powered by batteries with limited lifetimes. Energy consumption for broadcast operations can be reduced by minimizing the number of relay nodes based on the ...

An optimum sensor node placement mechanism for Wireless Sensor Network (WSN) is desirable in ensuring the location of sensor nodes that offers maximum coverage and connectivity with minimum energy consumption. This paper proposes a sensor node placement algorithm that utilizes a new biologically inspired optimization algorithm that imitates the behaviour of territorial predators in marking thei...