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Problem statement: Communication and control are two main components in any Mechatronics system. They can be designed either by centralized or decentralized approach. Both approaches can be chosen based on application designed and specific requirements of the designer. In this study, decentralized or normally called distributed approach was selected to solved communication and control of a human adaptive mechanical system namely Intelligent Chair Tools (ICT). The ICT seating system is powered by thirty six intelligent pneumatic actuators to facilitate investigation of chair shapes from spring and damping effect of seating and backrest surface. Three studies are proposed from the sitting experiments namely chair shapes, chair spring and chair damping properties. Approach: PSoC microcontroller was selected based on its features of having configurable analog and digital blocks. Its flexible modules and programmable peripherals ease designer in designing the communication and control of ICT in improved and faster way. Three protocols of USB, SPI and [I.sup.2]C were used for the communication system of ICT using PSoC. Flow charts of each communication protocols algorithms were discussed. On the other hand, the control system used PSoC's ADC and counter modules to read inputs of pressure and encoder respectively. PWM module is used to control the valve and data communication was achieved using [I.sup.2]C module. Block diagram of unified control was discussed for further understandings of the control algorithms. Results: The PSoC specification, development design and experimental evaluation of ICT system are presented and discussed. Three studies of chair shapes, chair spring property and chair damping property from sitting experiment were shown. Conclusion/Recommendations: The PSoC microcontroller selection was discussed and application of its distributed communication and control was successfully applied to ICT. This distributed approach can be applied to other application suitable for local control approach for easy debugging, more modular design and intelligence in deciding output based on feedback inputs. Key words: Distributed communication and control, PSoC, human machine interaction, ergonomics, INTRODUCTION Programmable System on Chip (PSoC) represents a whole new concept in microcontroller development. The mixed signal arrays of Cypress integrate an 8 bit microcontroller with analogue and digital components [...]

Problem statement: A great deal of excitement has recently propelled Mobile Learning to the forefront of educational technology. The exponential growth of mobile technology in the recent years, increase in the availability of high-bandwidth network, advances in wireless technologies and popularity of handheld devices, have opened up new accessibility opportunities for education. Approach: Virtual class room using MANET had been proposed to enhance the m-Learning opportunities in a residential institution. Results: This environment transferred both large and small volume of data to the particular group members. Generally multicasting supports group oriented computing. Such a group oriented service required a suitable multicast routing protocol. Two standard multicast routing protocols were implemented and analyzed for tree (MAODV) and mesh (ODMRP) based approach. The performances of group learning module of VCR had been analyzed using MAODV and ODMRP routing protocols for parameters such as network traffic, the node speed and the network area. Conclusion/Recommendations: Our results showed that many scenarios in VCR environment, MAODV achieved a higher packet delivery ratio than ODMRP. Key words: Mobile learning, mobile ad hoc network, personal digital assistant, multicast routing, virtual class room, INTRODUCTION Mobile learning activities can be suited to an indoor or outdoor environment. Also, either a single learner or a group of learners can participate in the learning activity. The [...]

Problem statement: A major drawback in the existing protocols in dealing with energy management issues is that the time varying nature of the wireless channels among the ad hoc nodes is ignored. Approach: This study proposed a channel adaptive energy efficient Medium Access Control (MAC) protocol, for efficient packets scheduling and queuing in an ad hoc network, with time varying characteristic of wireless channel taken into consideration. Every node in the proposed scheme estimates the channel and link quality for each contending flow based on which a weight value is calculated and propagated using the routing protocol. Since a wireless link with worse channel quality can result in more energy expenditure, the transmission was allowed only for those flows whose weight is greater than Channel Quality Threshold (CQT). For flows with weight less than CQT, the packets were buffered until the channel and link quality recovers or the weight becomes greater than CQT. To avoid buffer overflow and achieve fairness for the poor quality nodes, a fair scheduling and queuing algorithm is designed where in the CQT is adaptively adjusted on basis of the current incoming traffic load. Results: Simulation results showed that the proposed MAC protocol achieves substantial energy savings with better fairness and increased throughput. Conclusion: The designed protocol provided an efficient packets scheduling and queuing in an ad hoc network, with time varying characteristic of wireless channel taken into consideration. Key words: AdHoc networks, MAC protocol, scheduling, energy saving, bandwidth, INTRODUCTION In recent years, more attention has been given to ad-hoc wireless networking, enabling many interesting usage scenarios however several challenges are being posed. Conventionally, cellular telephony and Internet connectivity [...]

Problem Statement: With the free flow of routing data and the high availability of computer resources, possible threats to the networks can result in loss of privacy and in malicious use of information or resources that can eventually lead to large monetary losses. Approach: MD5 Authentication: Due to the major role that routing protocols play in computer network infrastructures, special cares has been given to routing protocols with built-in security constraints using authentication techniques, MD5 will be presented for this work. Results: The study evaluates the impact of the MD5 authentication on routing traffic for the case of EIGRP, RIPv2 and OSPF routing protocols in case of secured and non-secured routing traffic and measures the delay time, jitter and overhead. Conclusions: This study shows that the average delay time and jitter in the secured MD5 case can become significantly larger when compared to the unsecured case even in steady state conditions. Also, the EIGRP protocol shows the minimum overhead even when the system is extremely overloaded. Keywords: Impact of MD5, EIGRP, RIPv2, OSPF, and secured routing protocols, INTRODUCTION The past few years have witnessed an ever-growing reliance on computer networks for business transactions. With the free flow of data and the high availability of computer resources, owners [...]

AODV is a prominent routing protocol for MANET that uses hop count as a path selection metric. However, AODV has no means to convey traffic load on current route. This study focuses on introducing a new metric, Aggregate Interface Queue Length (AIQL), in AODV in order to deal with load balancing issues. Performance evaluation through simulation shows that the modified code can perform better than the conventional AODV. We also evaluate the effect of interface queue length on normalized routing load, average throughput and average end-to-end delay. Key words: Ad hoc networks, aggregate interface queue length, average throughput, normalized routing load, end-to-end delay, INTRODUCTION A mobile ad hoc network is defined as a collection of mobile platforms or nodes where each node is free to move about arbitrarily. Each node logically consists of [...]

Quantum Error Correction will be necessary for preserving coherent states against noise and other unwanted interactions in quantum computation and communication. We develop a general theory of quantum error correction based on encoding states into larger Hilbert spaces subject to known interactions. We obtain necessary and sufficient conditions for the perfect recovery of an encoded state after its degradation by an interaction. The conditions depend only on the behavior of the logical states. We use them to give a recovery operator independent definition of error-correcting codes. We relate this definition to four others: The existence of a left inverse of the interaction, an explicit representation of the error syndrome using tensor products, perfect recovery of the completely entangled state and an information theoretic identity. Two notions of fidelity and error for imperfect recovery are introduced, one for pure and the other for entangled states. The latter is more appropriate when using codes in a quantum memory or in applications of quantum teleportation to communication. We show that the error for entangled states is bounded linearly by the error for pure states. A formal definition of independent interactions for qubits is given. This leads to lower bounds on the number of qubits required to correct errors and a formal proof that the classical bounds on the probability of error-correcting codes applies to error correcting quantum codes, provided that the interaction is dominated by an identity component. Key words: The Heisenberg uncertainty principle, BB84 protocol, noise, quantum protocol, error code corrector, INTRODUCTION Within the past few years, quantum computation and communication have undergone a dramatic evolution. From being subjects of primarily academic interest, they have become fields having an enormous potential [...]

In mobile ad hoc networks, how to achieve the multicast communication is a challenging task due to the fact that the topology may change frequently and communication links may be broken because of users' mobility. We introduced MANHSI (Multicast for Ad hoe Network with hybrid Swarm Intelligence) protocol, which relies on a swarm intelligence based optimization technique to learn and discover efficient multicast connectivity. The proposed protocol instances that it can quickly and efficiently establish initial multicast connectivity and/or improved the resulting connectivity via different optimization techniques. Using a simulation approach, we investigated performance of the proposed algorithm through a comparison with an algorithm previously proposed in the literature. Based on the numerical results, we demonstrate that our proposed algorithm performs well. Key word: Mobile ad hoc networks, multicast algorithm, hybrid Swarm Intelligence, optimization techniques., INTRODUCTION In mobile wireless ad hoc networks attract increasing interest in many application domains since they may be the only solution in situations, where resources such as energy and bandwidth [...]