A Review on Proposed Implementation of VGDRA and its Comparative Analysis.

Recently, a virtual Grid-based dynamic routes adjustment scheme for mobile sink-based wireless sensor networks is introduced. This paper presents the proposed implementation of VGDRA and its comparative analysis, in which we are discussing the approach of efficient data delivery using communication of distance priority i.e. avoiding straight line communication which was used in previous VGDRA scheme. While maintaining nearly optimal routes to mobile sink’s latest location, our scheme aims to minimize the routes reconstruction cost of sensor nodes. In this approach energy model for reducing energy consumption of nodes is used, which will improves lifetime and also reduce cost consumption. DOI: 10.17762/ijritcc2321-8169.150614

Power Saving MAC Protocols for WSNs and Optimization of S-MAC Protocol

Low power MAC protocols have received a lot of consideration in the last few years because of their influence on the lifetime of wireless sensor networks. Since, sensors typically operate on batteries, replacement of which is often difficult. A lot of work has been done to minimize the energy expenditure and prolong the sensor lifetime through energy efficient designs, across layers. Meanwhile, the sensor network should be able to maintain a certain throughput in order to fulfill the QoS requirements of the end user, and to ensure the constancy of the network. This paper introduces different types of MAC protocols used for WSNs and proposes S‐MAC, a Medium‐Access Control protocol designed for Wireless Sensor Networks. S‐MAC uses a few innovative techniques to reduce energy consumption and support self‐ configuration. A new protocol is suggested to improve the energy efficiency, latency and throughput of existing MAC protocol for WSNs. A modification of the protocol is then proposed to eliminate the need for some nodes to stay awake longer than the other nodes which improves the energy efficiency, latency and throughput and hence increases the life span of a wireless sensor networ

REVIEW ON HIERARCHICAL ROUTING IN WIRELESS SENSOR NETWORKS

The Wireless Sensor Network(WSN) has become an interesting field of research of the 21st century. It is a type of the wireless ad-hoc network. This has brought about developing low cost, low-power and multi-function sensor nodes. The network life for wireless sensor network plays an important role in survivability. Energy efficiency is one of the critical concerns for wireless sensor networks. Sensor nodes are strictly constrained in terms of storage, board energy and processing capacity. For these reasons, many new protocols have been proposed for the purpose of data routing in sensor networks. These protocols can be classified into three main categories: data-centric, location-based and hierarchical. This paper mainly deals with some of the major Energy-efficient hierarchical routing protocols for wireless sensor networks. First we will discuss the energy-efficient Hierarchical routing protocols in brief along with their important features, objectives, drawbacks and area of application. Finally, we provide a comparison of these various protocols

BER Performance Analysis of Frequency-Hopping and Direct-Sequencing Spread Spectrum for Cognitive Radio Networks

Cognitive radio is an encouraging technology for future wireless communication networks. Due to the rapid increase in wireless services, the RF spectrum is going through a scarcity problem. This has forced mobile operators to participate in multi-million dollar auctions to reserve some spectrum resources. Cognitive radio tries to solve this scarcity problem by effectively using the unused portions of the spectrum. FHSS and DSSS are two spread spectrum technologies used for cognitive radios. In this paper, both techniques have been discussed extensively. DSSS accesses spectrum in a sequence whereas FHSS accesses spectrum by a hopping sequence and thus provide immunity to interference and jamming signals. Also, they have been concatenated to cognitive radio and analyzed to find which spread spectrum technology provides better communication. Simulations have been performed in MATLAB environment and results are shown in the form of number of error bits (BER) generated for a range of SNR values. DOI: 10.17762/ijritcc2321-8169.150514

MRI: an update and review on bio-effects and safety considerations

Diagnostic imaging technologies such as magnetic resonance (MR) are vital to catching signs of disease early and high quality diagnosis for treatment planning. However, some patients are unable to take advantage of its life saving capabilities. The procedures can be claustrophobic and the contraindications of MRI in patients having implants, pacemakers and also the risks associated with the use of cryogens, contrast agents etc. So this article provides an update on review on the bio effects and safety considerations for both patient and health practitioner with respect to the use of clinical MRI

SAFEGUARDING AGAINST IMPROPER CONFIGURATIONS FOR LORAWAN GATEWAYS

Presented herein are safeguard features for Long Range wide-area network (LoRaWAN) deployments on a LoRa gateway. The techniques presented herein provide a solution to prevent end users from wrongly or accidentally deploying LoRa gateways in unlawful Industrial, Scientific and Medical (ISM) radio bands. The techniques presented herein require little computational and storage resources to be integrated into any LoRa gateway embedded system, operate automatically based on the standard LNS protocol, and are sufficiently flexible to suit different use cases

Noise levels in a dental teaching institute: a matter of concern!

Objective: To measure and assess the noise levels produced by various dental equipments in different areas of a dental institution and to recommend improvements if noise levels are not within permissible limits. Materials and methods: Sound levels were measured at three different areas of a dental institution where learning and teaching activities are organized. The sound level was measured using a sound level meter known as 'decibulolmeter'. In each area the noise level was assessed at two positions-one, at 6 inches from the operators ear and second, at the chairside instrument trolley. Noise levels were also assessed from a central location of the clinic area when multiple equipments were in operation simultaneously. Results: Dental laboratory machine, dental hand-piece, ultrasonic scalers, amalgamators, high speed evacuation, and other items produce noise at different sound levels which is appreciable. The noise levels generated varied between 72.6 dB in pre-clinics and 87.2 dB in prosthesis laboratory. The results are comparable to the results of other studies which are conducted elsewhere. Although the risk to the dentists is lesser, but damage to the hearing is possible over prolonged periods. Conclusion: Higher noise levels are potentially hazardous to the persons working in such environments especially in the laboratory areas where noise levels are exceeding the permissible limits

Copper removal from acid mine drainage-polluted water using glutaraldehyde-polyethyleneimine modified diatomaceous earth particles

Mine waters and tailings generated from mining and mineral processing activities often have detrimental impact on the local environment. One example is acid mine drainage, in which sulphides in the mining waste react with water and oxygen to produce an acidic environment that subsequently dissolves host rock minerals from the waste containing toxic metals and trace elements. Copper is one such metal of significance, as it is mined at large volumes in sulphide containing ores. It has strong biocidal activity that greatly affects ecosystems. We have previously reported that glutaraldehyde (GA)-crosslinked polyethyleneimine (PEI) has strong affinity and selectivity for copper and that diatomaceous earth (DE) particles can be modified with the material to form a copper-extraction resin. In this study, the copper uptake of GA-PEI-DE particles was investigated from synthetic and real acid mine drainage samples under different pHs and their copper removal performance was compared with that of selected commercial resins. The results revealed that copper could effectively and preferentially bind to the material at pH 4, and that the copper could be completely eluted by lowering of the pH. In addition, effective copper uptake and elution was demonstrated using real legacy acid mine drainage water from Mount Lyell in Tasmania

Dental Lasers: A Review of Safety Essentials

The laser technology offers a wide range of uses in dentistry with certain advantages to the general dental practitioner like bloodless surgery, minimal post-operative pain, reduction of operative time and high patient acceptance. Patient acceptance has also been demonstrated in various studies. Apart of these major advantages, safety regarding the use of lasers cannot be neglected and has become an important concern in this modern era of dentistry, as application of this technology is growing day by day. Potential hazards can be encountered while using lasers like ocular hazards, tissue injury, inhaling the vapor emitted by the laser procedure, fire and explosion hazards etc. The safe use of lasers includes all the individuals who might be exposed either deliberately or accidently while using lasers and effective measures that can be undertaken by clinicians and health professionals to minimize the injuries caused due to laser accidents. The present article serves to explore the risks involved in the use of lasers in dentistry and suggest some of the laser safety protocols/measures that can be established in the dental office for prevention of laser injuries