Evolutionary optimization of Haferman carpet fractal patterned antenna array

This article investigates radiation characteristics of a new type of fractal shaped antenna array based on Haferman carpet geometry. An iterative feed matrix eases the complexity of array factor calculation that makes the array factor suitable for the application of any evolutionary optimization techniques. It is seen that Haferman carpet array produces peak side lobe level (PSLL) better than Sierpinski carpet that produces ?10 dB PSLL at every stage of growth. Optimization techniques have been applied for array element reduction and PSLL minimization at different stages of growth. Here, PSLL is minimized by turning off array elements and also by varying inter element spacing between the array elements. The optimized version of Haferman carpet array produces better characteristics (49.38% thinning with ?20.5 dB PSLL for stage‐2, 46.3% thinning with ?22 dB PSLL for stage‐3 and 42.3% thinning with ?21dB PSLL for stage‐4) than its original counterpart in terms of reduced element count and PSLL. Numerical results for obtaining optimized array performance exploit both DE as well as PSO. A comparative study on the performance is also presented. As a whole, Haferman carpet is seen to be more effective approach than Sierpinski carpet in fractal antenna paradigm. © 2015 Wiley Periodicals, Inc. Int J RF and Microwave CAE 25:719–729, 2015.     

Kinetics of combined noncatalytic and catalytic hydrolysis of jute fiber under ultrasonic–far infrared energy synergy

Hydrolysis of pretreated waste jute fiber was intensified for maximizing reducing sugar (RS) yield deploying a novel reactor equipped with ultrasonic–far-infrared-waves (US–FIRW). At optimal 70°C temperature, 2.5 wt% Amberlyst-15 catalyst concentration, 15 min hydrolysis time and 10 (wt/wt) water loading; US–FIRW rendered significantly greater RS yield (74.82 mol%) compared to other reactors provided with far-infrared-wave (69.63 mol%), ultrasonication (50.34 mol%), and conventional thermal system (48.16 mol%). Kinetic models were developed considering noncatalytic-pseudo-homogenous (NCPH) in addition to the combined catalytic-pseudo-homogeneous (CPH) and catalytic heterogeneous (CHE) hydrolysis pathways. The results revealed that pseudo-homogenous–heterogeneous Eley–Rideal (PHHER) model could represent the hydrolysis kinetics most accurately. Remarkably, the lowest activation energy [16.75 kJ mol⁻¹ (NCPH), 13.82 kJ mol⁻¹ (CPH), 40.01 kJ mol⁻¹ (CHE)] required in US–FIRW evidently established its greater energy-efficiency among investigated reactors. The novel reactor and the simulated kinetic models can be applicable to other lignocellulosic biomass conversion for sustainable biorefinery.     

Recent epidemiological status of malaria in Calcutta Municipal Corporation area, West Bengal

In Calcutta, Plasmodium falciparum cases and death due to malaria show remarkably increasing trend since 1990. The incidence of P. falciparum malaria has increased more than eleven folds in 1996 in comparison to 1990, with 0, 0, 0, 3, 7, 52 and 17 deaths in 1990, 1991, 1992, 1993, 1994, 1995 and 1996 respectively. Situation is more serious than what it is projected in official records as annual blood examination rate (ABER) in Calcutta Municipal area is poor, varying from 1.5 to 3.9 in 1993 and 1996 respectively. This is further evident from the fact that in a study area in 19 months (January 1995 to July 1996) the slide positivity rate (SPR) was 47.94% on an average 28.72% suffer from P. falciparum infection (as low as 0.5% in June 1996 and as high as 71.5% in November 1996). For the first time resistance of P. falciparum to chloroquine has been noted at RII and RIII level. The response of the same parasite strain to sulfa-pyrimethamine combination drug is very much promising. Fresh infection is occurring in all the months of the year and the favourable period is from July to November 1995 that is corroborating with Container index and Breteau index related to the vector mosquito Anopheles. Susceptibility status of An. stephensi indicates that the mosquito species has acquired resistance to DDT, BHC, propoxure and malathion but is still susceptible to fenthion and deltamethrin.     

Multifunctional greener additives for lubricating oil

In an anticipation to produce biodegradable additives with multifunctional performance for a cost‐effective lubricant composition, copolymers are synthesized by incorporating rice bran oil, peanut oil, β‐pinene in the backbone of isodecyl acrylate through microwave irradiation method using AIBN (azobisisobutyronitrile) as radical initiator. The prepared polymers are characterized by spectral techniques (IR, NMR) and SEC‐GPC analysis, thermal stability was determined by thermogravimetric analysis. Performance of the polymers as antiwear (AW), pour point depressant (PPD), viscosity modifier/viscosity index improver (VII) in different mineral base oils (SN1 and SN2) were done by standard ASTM methods. Biodegradability test of the polymers was carried out by disk diffusion (DD) and soil burial test methods. The copolymers of rice bran oil showed better viscosity index values and AW property, whereas the copolymers of peanut oil found to be most effective as PPD. Copolymers with higher concentration of green units showed better performance as viscosity modifier, pour point depressant and AW performance along with excellent biodegradability. POLYM. ENG. SCI., 2017. © 2017 Society of Plastics Engineers     

EOCGS: energy efficient optimum number of cluster head and grid head selection in wireless sensor networks

Telecommunication Systems -     

Energy-efficient adaptive GTS allocation algorithm for IEEE 802.15.4 MAC protocol

Telecommunication Systems - The standard IEEE 802.15.4 fails to perform optimally for railway monitoring applications due to the deficiency of guaranteed time slots (GTSs). In the present work, an...     

Design and Implementation of Routing Algorithm to Enhance Network Lifetime in WBAN

Today’s era is the era of smart and remote applications exploiting advancement in sensors, cloud, Internet of things etc. Major application is in healthcare monitoring and support using wireless body area network (WBAN) in which sensor nodes sense vital physiological parameters and send to server through sink i.e. smart phone nowadays for seamless monitoring. The most significant issue in such applications is energy efficiency which leads to enhanced network life time that ensures uninterrupted seamless services. From source to sink data transmission may occur considering three different scenarios: source to sink single hop direct data transmission irrespective of in-between node distance, source to sink multi hop data transmission in which transmission range of source node is fixed at a threshold to find next forwarder node and transmission range of source node is incremented by affixed value until data gets transmitted to sink. In this work WBAN having different network configurations based on fixed or random positions of nodes have been simulated. Different scenarios with fixed and varying number of nodes are framed and simulated using MATLAB 2020a for performance evaluation of proposed algorithm in terms of energy consumption, network lifetime, path loss etc. due to data transmission from source to sink. Experimental results show that incremental approach is better than direct one in terms of energy consumption, path loss and network lifetime. While selecting transmission range of a source node, it is considered to keep Specific Absorption Rate (SAR) lower to reduce impact on human tissue.

     

Comprehensive design methodology for control and data planes in wavelength-routed optical networks

We propose a comprehensive design methodology for control and data planes of wavelength-routed optical networks (WRONs) employing mixed-line-rate (MLR) transmission for cost-effective resource provisioning. The proposed approach attempts to minimize the maximum lightpath capacity demand in Gbps (representing the measure of lightpath congestion) in network for a given traffic matrix by using a mix of a heuristic scheme and linear programming (LP). In the first step of the proposed three-step design, some lightpaths are set up on a set of judiciously selected fiber links (with point-to-point lightpaths between neighboring nodes), on a specific wavelength throughout the network, and an appropriate fraction of the same set of lightpaths is utilized for carrying control information, forming therefore the control plane (CP) of the WRON. The remaining bandwidth of these lightpaths is utilized to carry the data traffic along with all other designed lightpaths of the WRON using appropriate algorithm, forming the overall data plane (DP) of the WRON. In the second step, traffic routing is carried out through LP to minimize lightpath congestion in the network. In the third step, we utilize the results of LP to assign rates to lightpaths, such that the cost (considering only the transceiver cost) of the network is minimized. This design leads to congestion-aware MLR network with due consideration to cost-effectiveness without compromising the network restoration response against link failures. We carry out simulation studies employing possible CPs using both symmetric (CP topology being same as the physical topology) as well as asymmetric (using fewer fiber links than the symmetric case) topology. The results of our simulations indicate that the proposed design of CP with symmetric/asymmetric topology and in-band transmission with sub-lightpath capacity can bring down network congestion and cost with respect to symmetric out-of-band transmission (using fully reserved lightpaths for CP), without any perceptible sacrifice in respect of the network restoration time. Failure can occur either in CP or DP, or in both the planes. We investigate the effect of design of CP with symmetric/asymmetric topology on network restoration time for single- and double-link failures. We further present DP design methodology with hybrid restoration scheme, i.e., combination of dedicated (1:1) path protection and path restoration. We analyze the effect of symmetric CP topology and degree of protection on the congestion of the network. Some lightpaths, that support more traffic, are protected against failures, while the others are left for path restoration in the event of failures. As more lightpaths are protected, the congestion and power consumption of network increase. We provide an analysis of the factors that come into play while altering the degree of protection and observe how the choice for the degree of protection in DP can be arrived at using an appropriate design methodology.