V_THR: An Adaptive Load Balancing Algorithm

This paper presents a new adaptive algorithm for dynamic load balancing on a shared BUS architecture. We present results obtained from simulation studies and queuing analysis, which reflect the relation between the BUS contention and the efficiency of load balancing. The proposed algorithm uses a scheme for monitoring theThresholdparameter to dynamically adapt itself to the limited bandwidth of the shared BUS. We have compared our algorithm with some of the known policies, and the relative performance appears to be promising.     

On image enhancement and threshold selection using the graylevel co-occurence matrix

A new contrast enhancement technique using second-order graylevel statistics is reported here. The value of the threshold, which is required to define the graylevel transformation function, is found out depending on the average contrast between different regions. The algorithm is implemented on some images and results are shown.     

Micromechanical switches fabricated using nickel surfacemicromachining

Micromechanical switches have been fabricated in electroplated nickel using a four-level surface micromachining process. The simplest devices are configured with three terminals, a source, a drain, and a gate and are 30 μm wide, 1 μm thick, and 65 μm long. A voltage applied between the gate and source closes the switch, connecting the source to the drain. Devices switch more than 10⁹ cycles before failure and exhibit long-lifetime hot switching currents up to 5 mA. The initial contact resistance is less than 50 mΩ. The breakdown (stand-off) voltage between the source and the drain is greater than 100 V and the off-current is less than 20 fA at 100 V     

Properties and some fast algorithms of the Haar transform in image processing and pattern recognition

Properties of the Haar transform in image processing and pattern recognition are investigated. A lower bound of the performance of the Haar transform relative to that of the Karhunen-Loeve transform for first-order Markov processes is found. It is proved that the Haar transform is inferior to the Walsh-Hadamard transform for such processes. A unique condition is presented which, if satisfied by the elements of a matrix, will make the Karhunen-Loeve transform of the matrix and the Haar transform equivalent. Some fast algorithms are given to realize the diagonal elements of a Haar transformed matrix.     

MAAS: A mobile cloud assisted architecture for handling emergency situations

Recent advancements in the area of Mobile Cloud Computing (MCC) have significantly contributed towards assisting mankind to handle varied types of emergency situations that may arise as a result of different natural calamities like earthquakes, floods, fire, etc, which may cause huge damage to public property and result in loss of wealth of the nation. In this work, we have proposed a mobile cloud assisted architecture that supports the multicloud and hybrid‐cloud environments, together with Cloud Probing Service (CPS) and Cloud Ranking Service (CRS). The proposed algorithm consumes data from the sensor nodes and offloads the data to the most suitable cloud. A three‐layered architecture has been proposed, and the anchor points facilitate in the creation of the interface between the different layers. The simulation results indicate that the proposed mobile cloud assisted architecture for handling emergency situations (MAAS) approach performs better than the baseline algorithms.     

ECC-CoAP: Elliptic Curve Cryptography Based Constraint Application Protocol for Internet of Things

Constraint Application Protocol (CoAP), an application layer based protocol, is a compressed version of HTTP protocol that is used for communication between lightweight resource constraint devices in Internet of Things (IoT) network. The CoAP protocol is generally associated with connectionless User Datagram Protocol (UDP) and works based on Representational State Transfer architecture. The CoAP is associated with Datagram Transport Layer Security (DTLS) protocol for establishing a secure session using the existing algorithms like Lightweight Establishment of Secure Session for communication between various IoT devices and remote server. However, several limitations regarding the key management, session establishment and multi-cast message communication within the DTLS layer are present in CoAP. Hence, development of an efficient protocol for secure session establishment of CoAP is required for IoT communication. Thus, to overcome the existing limitations related to key management and multicast security in CoAP, we have proposed an efficient and secure communication scheme to establish secure session key between IoT devices and remote server using lightweight elliptic curve cryptography (ECC). The proposed ECC-based CoAP is referred to as ECC-CoAP that provides a CoAP implementation for authentication in IoT network. A number of well-known cryptographic attacks are analyzed for validating the security strength of the ECC-CoAP and found that all these attacks are well defended. The performance analysis of the ECC-CoAP shows that our scheme is lightweight and secure.

     

Exploring a reversible NOR from a 4 × 4 modified Fredkin gate and its optical mapping using a LiNbO3-based MZI

Journal of Computational Electronics - The extensive search for the implementation of reversible logic using emerging technologies has paved the way for the rise of optical computing. The...     

Analytical prediction of resonant frequencies of annular stacked dielectric resonator antennas

The method of stacking dielectric resonators for designing multiband and wideband antennas has gained much attention in recent times. However, the existing works lack any theoretical framework for the prediction of resonant frequencies of such stacked structures. In this work, a formal analysis using a cavity model with the mode matching technique is presented to determine all the existing resonant frequencies of annular stacked cylindrical dielectric resonator antennas with and without air gap. The analysis is done separately considering the outermost sidewall of the stack as both perfect magnetic conductor and imperfect magnetic conductor. The theoretical findings are extensively validated against numerous simulations, as well as against a fabricated prototype. It is observed that the perfect magnetic wall condition provides results that are more accurate. The closed‐form equation derived in this work not only helps in accurately predicting the resonant frequencies but also reduces the run‐time manifolds compared to that of the existing trial and error based methods of design using software simulations.     

Goubau line based end‐fire antenna

This article proposes a simple and low profile planar Goubau line based end‐fire antenna. End‐fire radiation is achieved by modifying the Goubau line into inverted periodic arrangement of V‐shaped unit cells. Designed prototype is simulated and verified experimentally. Both the simulated and measured results are in good agreement. Proposed antenna radiates toward end‐fire direction between 7.8 and 8.3 GHz. The maximum gain of the antenna is obtained around 7.2 dBi. The average efficiency is observed 70% over the entire operating bandwidth. Proposed end‐fire antenna has a single metallic layer with simple configuration which is easy to fabricate and also easy to integrate with other electronics circuits. The proposed antenna can be used for satellite and RADAR applications.