Energy efficient and QoS aware routing protocol for Clustered Wireless Sensor Network

In this paper, a protocol called Energy Efficient and QoS aware Routing (EEQR) protocol for Clustered Wireless Sensor Network is proposed. To ensure QoS for different traffic types, prioritization of data is done based on message type and content. To address energy efficiency (hotspot problem) and high end-to-end delay problem, a combination of mobile and static sink is used for data gathering. Delay sensitive message are sent through the static sink and delay tolerant message are send through the mobile sink. Consequently, EEQR incurs less end-to-end delay, is energy efficient as well as able to ensure QoS. To evaluate the performance of the proposed strategy, intensive simulations are carried out. Performance of the proposed strategy is compared with the static sink and mobile sinks strategies. The results demonstrated that EEQR has prolonged the network and coverage lifetime, as well as has improved the other QoS routing parameters, such as delay, packet loss ratio, and throughput.     

Effects of silica aerogel particle sizes on the thermal–mechanical properties of silica aerogel – unsaturated polyester composites

Silica aerogels with a surface area as high as 773?m²?g^?1 and a density of 0.077?g?cm^?3 were produced from rice husk via sol–gel process and ambient pressure drying. A particulate composite material was prepared by adding silica aerogel particles of three different particle sizes (powder, granules and bead) to unsaturated polyester resin with a fixed volume fraction of 30%. Thermogravimetric and thermal conductivity studies revealed that silica aerogel composites were having higher thermal stability and thermal insulation than the neat resin. It was suggested that the preservation of aerogel pores from resin intrusion is important for better thermal properties. Larger silica aerogel particles have more porous area (unwetted region) which results in a lower degradation rate and lower thermal conductivity of the base polymer. However, the addition of silica aerogel into resin has reduced the tensile modulus of the polymer matrix where smaller particle size displayed higher toughness than those with bigger particle size.     

Chip morphology study in high speed drilling of Al�CSi alloy

Chip formation during drilling operation is greatly influenced by the cutting parameters such as cutting speed, feed rate, and drill geometry. However, not many studies have focused on the direct observation of the chip formation during high speed drilling. This paper investigates the effect of cutting speed and feed rate on the chip morphology during high speed drilling of aluminum?Csilicon alloys using carbide drill. Observation on the multiview characterization of the chips was carried out which includes free surface, back surface, and cross-section of top surface. Structure and shape alterations of the free and back surfaces were analyzed using a scanning electron microscope. Finally, different geometrical parameters of chip cross-section were measured in order to study the effect of cutting parameters on chip compression ratio and thrust force. It was found that increase in cutting speed significantly affects the chip morphology especially on the structure of free surface and cross-section of the chips. Results also showed that built-up edge on the rake face of tool played an important role on the formation of irregular pattern on the chip back surface.     

Efficient Energy Utilization Through Optimum Number of Sensor Node Distribution in Engineered Corona-Based (ONSD-EC) Wireless Sensor Network

An optimum sensor node deployment in wireless sensor network can sense the event precisely in many real time scenarios for example forests, habitat, battlefields, and precision agriculture. Due to these applications, it is necessary to distribute the sensor node in an efficient way to monitor the event precisely and to utilize maximum energy during network lifetime. In this paper, we consider the energy hole formation due to the unbalanced energy consumption in many-to-one wireless sensor network. We propose a novel method using the optimum number of sensor node Distribution in Engineered Corona-based wireless sensor network, in which the interested area is divided into a number of coronas. A mathematical models is proposed to find out the energy consumption rate and to distribute the optimum number of sensor node in each corona according to energy consumption rate. An algorithm is proposed to distribute the optimum number of sensor nodes in corona-based networks. Simulation result shows that the proposed technique utilized 95 % of the total energy of the network during network lifetime. The proposed technique also maximizes the network lifetime, data delivery and reduce the residual energy ratio during network lifetime.     

What is the Value of Limited Feedback for Next Generation of Cellular Systems?

Wireless Personal Communications - The demand for higher data traffic is exponentially growing. Since last 2 years or so, new research movements have emerged towards LTE-B (Release 13 and...     

Investigation and experimental verification of the effectiveness of the interfaced plate parameters on impact-based piezoelectric energy harvester

This paper studies and validates the potential of the performance and output efficiency for the impact-mode piezoelectric energy harvesting system by introducing the additional interfaced plate. The interfaced plate is allocated between the ball dropped and piezoelectric disc. Therefore, the ball hits the piezoelectric disc indirectly. The impact force will be altered depending on different values of ball mass and height dropped. The two parameters such as diameter and height of the interfaced plate are investigated. The output efficiency of the piezoelectric disc increases when the diameter of the interfaced plate is decreased. While the amplitude of the output voltage and power increase as the height of the interfaced plate is increased. These statements are proven and determined by the results obtained in this paper. However, the output voltage and power of the piezoelectric disc without the interfaced plate is higher than the output power of the interfaced plate that is employed on the piezoelectric disc when the free fall experiment (instantaneous impact force) is conducted.     

Effects of electron radiation on commercial power MOSFET with buck converter application

Microelectronic power converters such as buck and boost converter are required to be tolerant to radiations including electron radiation. This paper examines electron radiation effects on the Ⅰ-Ⅴ characteristics of VDMOSFET and its corresponding effects in buck converter. Analysis of the electrical characteristics shows that after irradiation the threshold voltage and drain current for all VDMOSFETs degraded more than two orders of magnitude. The impact of this electrical degradation has been investigated in an application of typical buck converter circuit. The buck converter with n-channel switching transistor shows that after irradiation its output voltage increased with the drain current in the n-channel ZVN4424 A VDMOSFET, while the buck converter with p-channel switching transistor shows its output voltage decreased with the drain current in the p-channel ZVP4424 A VDMOSFET after irradiation.     

Iron oxide nanoparticles improved biocompatibility and removal of middle molecule uremic toxin of polysulfone hollow fiber membranes

Middle molecule uremic toxins constitute to a quarter of uremic toxins present in human blood. In a condition where these uremic toxins accumulate in bloodstream due to renal failure, blood purification process using a high performance membrane is required. Here, we develop biocompatible mixed matrix membranes (MMMs) made up of polysulfone (PSf) and iron oxide nanoparticles (Fe₂O₃ NPs) with the focus to remove middle molecule uremic toxin effectively. The MMMs were evaluated in terms of their biocompatibility and separation performance. At higher Fe₂O₃ NPs loading, the MMM displayed a huge reduction of protein adsorption and platelet adhesion while maintaining normal blood coagulation time and acceptable complement activation. The optimized MMM exhibited high permeability (110.47 L m⁻² h⁻¹ bar⁻¹), protein retention (99.9%) and demonstrated excellent clearance of urea (82%) and lysozyme (46.7%). The PSf/Fe₂O₃ MMM is proven to have promising attributes for hemodialysis application. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 48234.     

Gene Therapy Targeting p53 and KRAS for Colorectal Cancer Treatment: A Myth or the Way Forward?

Colorectal cancer (CRC) is the third most commonly diagnosed malignancy worldwide and is responsible as one of the main causes of mortality in both men and women. Despite massive efforts to raise public awareness on early screening and significant advancements in the treatment for CRC, the majority of cases are still being diagnosed at the advanced stage. This contributes to low survivability due to this cancer. CRC patients present various genetic changes and epigenetic modifications. The most common genetic alterations associated with CRC are p53 and KRAS mutations. Gene therapy targeting defect genes such as TP53 (tumor suppressor gene encodes for p53) and KRAS (oncogene) in CRC potentially serves as an alternative treatment avenue for the disease in addition to the standard therapy. For the last decade, significant developments have been seen in gene therapy for translational purposes in treating various cancers. This includes the development of vectors as delivery vehicles. Despite the optimism revolving around targeted gene therapy for cancer treatment, it also has various limitations, such as a lack of availability of related technology, high cost of the involved procedures, and ethical issues. This article will provide a review on the potentials and challenges of gene therapy targeting p53 and KRAS for the treatment of CRC.     

Correction to: ZGLS: a novel flat quorum-based and reliable location management protocol for VANETs

Wireless Networks - The original version of this article contained an error in co-author’s affiliation. The correct affiliation of Dr. Waqas Rehan is given in this erratum.