Evaluating performance of WRP and AODV MANETs routing protocols under mobility

The Mobile ad hoc networks (MANET) is a wireless networks which have no central bridge, and where each node acts as a destination as well as a router. The MANETs are dynamic networks because the network topology keeps on changing because of the mobility of the nodes. There are many protocols that have been developed to aid in routing in these types of networks. Each of these protocols is designed with some certain mobility scenarios in mind. To achieve effective routing in a given scenario, the right protocol must be chosen. Choosing the right protocol involves  evaluating many interdependent performance metrics that define the effectiveness of a routing protocol, and this often poses a challenge to application designers. This research endeavored to model a simulation platform on which various protocols could be evaluated under various mobility scenarios to determine their suitability. The GloMoSim was used as the simulation platform and two MANET protocols namely wireless routing protocol (WRP) and ad hoc ondemand distance vector (AODV) evaluated. Our results demonstrated the usefulness of this modeled platform as it was able to establish that the AODV outperformed WRP in four out of the five of the measured performance metrics. The AODV is thus a better  protocol for MANETs compared to WRP. The same simulation platform could be used test other protocols.Key words: MANET, WRP, AODV, Simulation, GloMoSi

Driving With Single Deformable Polyline Tentacle and Velocity Obstacles

Intelligent transportation systems are emerging as the approach to dramatically improve efficiency while at the same time leading to the goal of zero accidents. Autonomous driving is now possible but still greatly limited to low speed driving. This is mainly due to computational load in detecting the road and objects, path planning and limited controller cycles. The focus of this work is to develop faster trajectory planning scheme given the sensed environment map (occupancy grid). This work utilizes interaction of single projected trajectory from the non-holonomic vehicle kinematic model with the objects in the road. Furthermore, the planned trajectory is made sensitive to car speed. Simulation results with non-linear vehicle kinematic model shows that the proposed combination of single trajectory and velocity objects gives faster satisfactory trajectory with safe obstacle avoidance while following prescribed way points. Key words: Deformable poly-line tentacle, Velocity objects, trajectory planning and non-holonomic constraints

Optimization of Base Station Location in 3G Networks using Mads and Fuzzy C-means

Distribution of Base Transceiver Stations (BTS) with an aim of maintaining high Quality of Service and coverage is important to mobile operators. Rapid expansion of telecommunication industry results in stiff competition among service providers which in turn leads to greater focus on quality of services delivered. Increase in number of mobile phone usage has also led to unprecedented network expansion. Coupled to these challenges is rapid change in telecommunication technology from 2G to 4G in a short space of time. A combination of MADS and FUZZY C- MEANS is used to aid in planning Base Station Transceivers (BTS) location efficiently in order to curb capital and maintenance costs. Keywords: BTS placement, MADS, Fuzzy C-Mean

Cluster Analysis using Spherical SOM

A cluster analysis method is proposed in this paper. As benchmark data, the Fisher's iris and the Wine recognition data sets are used. As a result of the numerical experiment, a clustering method using the dendrogram yielded 97 % in accuracy. It is difficult to display a multi-dimensional data by the dendrogram in one dimension. The ultimate visualization is by means of 3 dimensional rendition. We conclude that the best way that a multi-dimensional data set is visualized is by a sphere, since the phase relationship of it is smooth everywhere

Application of SOM in a health evaluation system

A health evaluation system was constructed which visualizes the living habits and health state from a person's checkup list by using the feature of SOM that multi-dimensional data can be mapped onto a two-dimensional surface. Here, three examples cases are reported. A change to the health region of the map by taking medication was visualized by the SOM from the conventional numerical expression. Also, the specific sick record converges towards the sick region of the map when the disease progresses. However, it was shown and visualized for the sick record not to converge in the case of the metastasis of a cancer even if for the same examinee, the cancer has progressed. Finally, for the display of the health point mark, and the display of the sick record, the spherical surface SOM, is demonstrated to be suited in the visualization

Performance of Magnetostrictive Amorphous Wire Sensor in Motor Speed Measurement

This paper presents the performance analysis of magnetostrictive amorphous wire in motor speed measurement. The principle of the operation of the sensor is based on Large Barkhausen Jump (LBJ), a unique feature of the wire. A dc motor is used due to the linear relationship between applied voltage and speed. The supply voltage of the dc motor is varied and motor speed measured. The frequency of the signal obtained from the magnetostrictive amorphous wire sensor is measured using an oscilloscope and the motor speed calculated from this frequency. Results obtained from amorphous wire sensor show quite good agreement with that of the digital tachometer. Keywords:  Large Barkhausen Jump (LBJ), Magnetostrictive Amorphous Wire, Speed senso

Effect of Length and Position Relative to the Rotor of the Magnetostrictive Amorphous Wire in Motor Speed Sensing

The performance of the magnetostrictive amorphous wire in motor speed sensing has been shown to match that of conventional motor speed sensors. The sensor is based on Large Barkhausen Jump, a unique feature of the wire, which occurs at a given critical length of the wire. A permanent magnet is also used and therefore depending on the strength of the magnet used, the position of the sensor relative to the rotor is expected to influence the results. This paper presents experimental results on the influence of length and position of the magnetostrictive amorphous wire on the performance of the sensor. A close observation on the signal waveforms indicate that there is a critical length and optimal positioning of the wire from the magnet for which the performance of the sensor is satisfactory Keywords:  Length, Magnetostrictive Amorphous Wire, Position, Speed sensin

Cluster Analysis using Spherical SOM

A cluster analysis method is proposed in this paper. As benchmark data, the Fisher's iris and the Wine recognition data sets are used. As a result of the numerical experiment, a clustering method using the dendrogram yielded 97 % in accuracy. It is difficult to display a multi-dimensional data by the dendrogram in one dimension. The ultimate visualization is by means of 3 dimensional rendition. We conclude that the best way that a multi-dimensional data set is visualized is by a sphere, since the phase relationship of it is smooth everywhere

Application of SOM in a health evaluation system

A health evaluation system was constructed which visualizes the living habits and health state from a person's checkup list by using the feature of SOM that multi-dimensional data can be mapped onto a two-dimensional surface. Here, three examples cases are reported. A change to the health region of the map by taking medication was visualized by the SOM from the conventional numerical expression. Also, the specific sick record converges towards the sick region of the map when the disease progresses. However, it was shown and visualized for the sick record not to converge in the case of the metastasis of a cancer even if for the same examinee, the cancer has progressed. Finally, for the display of the health point mark, and the display of the sick record, the spherical surface SOM, is demonstrated to be suited in the visualization

Collaborative Sociological Practice: the Case of Nine Urban Biotopes

This paper examines the socially engaged art project Nine Urban Biotopes (9UB), an international exchange between European and South African cultural organisations. Two artist residencies offer case studies of collaborative arts and research practice. The ways that these case studies are read as ‘failures’ and ‘successes’ illustrate the complexities of North- South collaborations. This project, the partnership that sustained it and the residencies that were central to it, exemplify, in modest ways, how public sociology can be realised in modest ways in a global context. This paper shows, with examples, that whilst partnership and collaboration are emphasised in institutional and policy discourse, in practice these arrangements are filled with tension and unequal power relations between partners. An evaluative methodology premised on sociological practice allows the tensions that are inherent in partnership and collaboration to be recognised and productively interrogated. It also allows us to reimagine what ‘success’ and ‘failure’ looks like in research partnerships by working with the antagonisms that are integral to collaboration