Universal aging properties at a disordered critical point

We investigate, analytically near the dimension $d_{uc}=4$ and numerically in $d=3$, the non equilibrium relaxational dynamics of the randomly diluted Ising model at criticality. Using the Exact Renormalization Group Method to one loop, we compute the two times $t,t_w$ correlation function and Fluctuation Dissipation Ratio (FDR) for any Fourier mode of the order parameter, of finite wave vector $q$. In the large time separation limit, the FDR is found to reach a non trivial value $X^{\infty}$ independently of (small) $q$ and coincide with the FDR associated to the the {\it total} magnetization obtained previously. Explicit calculations in real space show that the FDR associated to the {\it local} magnetization converges, in the asymptotic limit, to this same value $X^{\infty}$. Through a Monte Carlo simulation, we compute the autocorrelation function in three dimensions, for different values of the dilution fraction $p$ at $T_c(p)$. Taking properly into account the corrections to scaling, we find, according to the Renormalization Group predictions, that the autocorrelation exponent $\lambda_c$ is independent on $p$. The analysis is complemented by a study of the non equilibrium critical dynamics following a quench from a completely ordered state.Comment: 8 pages, 5 figure

Performance Evaluation of AODV Protocol Using NS2 Simulator

Mobile ad hoc networks (MANETs) represent complex distributed systems that comprise wireless mobile nodes which can dynamically self-organize into arbitrary and temporary, �ad-hoc� network topologies. This allows people and devices to seamlessly internetwork in areas with no pre-existing communication infrastructure. One interesting research area in MANET is routing. Routing in the MANETs is a challenging task and has received a tremendous amount of attention from researchers. This has led to development of many different routing protocols for MANETs. A mobile node is a collection point in the network which uses a particular protocol to forward data from source to destination. The nodes are free to move about and organize themselves into a network. The requirement of routing protocol is to send and receive information among the nodes with best suited path with the minimum delay. Correct and efficient route establishment between a pair of nodes is the primary goal of routing protocol. This paper is a simulation based analysis of Ad hoc on demand Distance Vector (AODV). The mobility models used in this work is Random Waypoint using network simulation tool NS2. The results presented in this work illustrate the performance of AODV routing protocols in an ad hoc environment

Integrating landscapes that have experienced rural depopulation and ecological homogenization into tropical conservation planning

If current trends of declining fertility rates and increasing abandonment of rural land as a result of urbanization continue, this will signal a globally significant transformation with important consequences for policy makers interested in conservation planning. This transformation is presently evident in a number of countries and projections suggest it may occur in the future in many developing countries. We use rates of population growth and urbanization to project population trends in rural areas for 25 example countries. Our projections indicate a general decline in population density that has either occurred already (e.g., Mexico) or may occur in the future if current trends continue (e.g., Uganda). Using both temperate and tropical examples we present evidence that this process will lead to ecological homogenization as a dominant habitat (e.g., forest replaces a mosaic of human-maintained landscapes), resulting in declines in biodiversity at the local scale. Building on this information, we consider research programs that need to be conducted so that policy makers are prepared to effectively manage depopulated rural areas

A new genus of scuttle fly (diptera: phoridae) from Malaysia

Imparphora gen. nov., a new genus of scuttle fly is described from Malaysia. The Imparphora pahangensis sp. nov. is the type species of the new genus. A total of six mature females species and a male were collected from baited traps along UKM’s Trail at Fraser’s Hill Research Centre, Pahang. These findings expand the species diversity of scuttle flies in Malaysia especially in the highland forest. The comparisons with the nearest genera were explained herein

Two-Hop Routing with Traffic-Differentiation for QoS Guarantee in Wireless Sensor Networks

This paper proposes a Traffic-Differentiated Two-Hop Routing protocol for Quality of Service (QoS) in Wireless Sensor Networks (WSNs). It targets WSN applications having different types of data traffic with several priorities. The protocol achieves to increase Packet Reception Ratio (PRR) and reduce end-to-end delay while considering multi-queue priority policy, two-hop neighborhood information, link reliability and power efficiency. The protocol is modular and utilizes effective methods for estimating the link metrics. Numerical results show that the proposed protocol is a feasible solution to addresses QoS service differenti- ation for traffic with different priorities.Comment: 13 page

Hybrid Neuro Fuzzy Control Based Isolated Asynchronous Generation Connect to Non-Linear Load

This paper deals with a hybrid neuro fuzzy control to isolated asynchronous generator (IAG) connected to non linear load. The proposed method utilizes an NN based on the least mean-square algorithm known as adaptive linear element to extract the fundamental component of load currents to control the voltage and the frequency of an IAG with load balancing in an integrated manner. The IELC is realized using zigzag/three single-phase transformers and a six-leg insulated-gate bipolar-transistor-based current controlled voltage-source converter, a chopper switch, and an auxiliary load on its dc bus. The proposed IELC, with the generating system, is modeled and simulated in MATLAB environment using Simulink and Simpower System toolboxes. The simulated results are validated with test results on a developed prototype to demonstrate the effectiveness of IELC for the control of an IAG feeding three-phase four-wire linear/nonlinear balanced/ unbalanced loads with neutral-current Keywords: Adaptive linear element (adaline), integrated electronic load controller (IELC), isolated asynchronous generator(IAG), small hydro generation, small hydropower generation, fuzzy