Exploiting Context-Awareness in Cluster-Based Wireless Sensor Networks

Most of the wireless sensor network's (WSN's) applications require getting accurate information as well as uninterrupted, prolonged service life. Among the constituting elements of WSN, an efficient routing protocol plays a significant role in attaining such service requirements. In this article, an energy efficient routing protocol, context-aware clustering hierarchy (CACH), is proposed where cluster formation is based on the context of the environment. Moreover, a technique is utilized to avoid similar data traffic across the network. The performance in the simulation shows energy saving which ensures prolonged service life. Copyright © 2009 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

PSO-based Parameter Tuning for a Two-Degree-of-Freedom IMC Scheme and Its Application to Paper Basis Weight Control

Basis weight is an important indicator for evaluating paper quality and a major factor directly affecting the economic benefits of enterprises. Focusing on the large time-delay, time-varying, and nonlinear characteristics of a basis weight control system, a two-degree-of-freedom(TDF) internal model control(IMC) method based on a particle swarm optimization(PSO) algorithm was proposed. The method took the integral of time multiplied by the absolute error(ITAE) as the objective function, and the PSO algorithm was used to optimize the time constant of the tuning IMC filter. The simulation results for the control system under the proposed TDF-IMC method based on the PSO algorithm demonstrate good set-point tracking performance, strong anti-interference capabilities, and good robustness properties. The application results revealed that the basis weight fluctuation range of the paper was ±2 g/m~2, which significantly improved both the control quality and the product quality.     

A new three-stage method for solving unit commitment problem

This paper presents a new Three-Stage (THS) approach for solving Unit Commitment (UC) problem. The proposed method has a simple procedure to get at favorite solutions in a feasible duration of time by producing a primal schedule of status of units at the first step. In the second step the operating units take hourly values by doing Economic Dispatch (ED) on them via a hybrid serial algorithm of Artificial Intelligence (AI) including Particle Swarm Optimization (PSO) and Nelder–Mead (NM) algorithms. In spite of the acceptable solutions obtained by these two stages, the presented method takes another step called the solution modification process (SMP) to reach a more suitable solution. The simulation results over some standard cases of UC problem confirm that this method produces robust solutions and generally gets appropriate near-optimal solutions.     

Cottage cheese whey as an ingredient of cottage cheese dressing mixes

The objective of this study was to formulate and develop a good quality cottage cheese dressing using acid whey as the main ingredient. Up to 72% of cottage cheese whey was used in the dressing mixes. The percentage of fat (4.10–5.05%) and total solids (19.41–20.24%) approached the desired level and was within the legal limits for regular cottage cheese. Sensory evaluation scores for flavour, body/texture and appearance were not adversely affected by the use of acid whey. The sensory evaluation scores for all four products made with whey- or skimmed milk-based dressings were higher than the commercial control.     

Synthesis of polymer/MWCNT nanocomposite catalyst supporting materials for high-temperature PEM fuel cells

In this study, the polymer/MWCNT nanocomposites were synthesized from the pristine MWCNT and polymer binders using functionalization with solution processing methods. The synthesized polymer/MWCNT nanocomposites exhibited high specific surface areas than the pristine MWCNT. The MWCNT/Nafion nanocomposite attributed to the maximum peak current at 5.795 × 10^?5 (A) while the peak current of MWCNT/PBI was obtained at 3.662 × 10^?5 (A). Moreover, polymer/MWCNT based electrocatalysts performed better electrochemical activity because of polymers binders can assist electrochemical interaction using the high surface areas of the catalyst supporting material. Also, the MEAs fabricated using the hot pressing method, while the acid doped PBI membrane sandwiched between the electrodes. The fabricated MEAs were successfully demonstrated in a single cell and found capable of measuring a maximum power density of 112.10 mW/cm² under 150 °C temperature. In conclusion, the synthesized catalyst-supporting materials enhanced the electrochemical activity and catalyst stability which fulfilling the main objective of this study.     

Panchromatic response composed of hybrid visible-light absorbing polymers and near-IR absorbing dyes for nanocrystalline TiO2-based solid-state solar cells

In pursuit of panchromatic sensitizers for mesoporous TiO₂-based solid-state solar cells, a near-IR absorbing zinc phthalocyanine dye (coded TT1) was firstly adsorbed over relatively thin (∼1 μm) TiO₂ mesoporous films and then a visible-light absorbing polymer [regioregular poly(3-hexylthiophene), P3HT] was incorporated into the mesopores as both a second sensitizer and a solid hole conductor. After optimizing some experimental parameters, these hybrid solid-state cells exhibited a clear panchromatic response, and an overall conversion efficiency of around 1% at full sun intensity.     

Mixed convective heat transfer enhancement in a ventilated cavity by flow modulation via rotating plate

The present study numerically explores the mixed convection phenomena in a differentially heated ventilated square cavity with active flow modulation via a rotating plate. Forced convection flow in the cavity is attained by maintaining external fluid flow through an opening at the bottom of the left cavity wall while leaving it through another opening at the right cavity wall. A counter-clockwise rotating plate at the center of the cavity acts as an active flow modulator. Moving mesh approach is used for the rotation of the plate and the numerical solution is achieved using arbitrary Lagrangian-Eulerian finite element formulation with a quadrilateral discretization scheme. Transient parametric simulations have been performed for various frequency of the rotating plate for a fixed Reynolds number (Re) of 100 based on maximum inlet flow velocity while the Richardson number (Ri) is maintained at unity. Heat transfer performance has been evaluated in terms of spatially averaged Nusselt number and time-averaged Nusselt number along the heated wall. Power spectrum analysis in the frequency domain obtained from the fast Fourier transform analysis indicates that thermal frequency and plate frequency start to deviate from each other at higher values of velocity ratio (>4).     

Short communication: Stall occupancy behavior of Nili Ravi buffaloes (Bubalus bubalis) when first introduced to freestall housing

The aim of the present study was to assess stall occupancy of Nili Ravi buffaloes when first introduced to freestall housing. Thirty Nili Ravi buffaloes of different parity, weight, and pregnancy status were enrolled from the dairy farm of the University of Veterinary and Animal Sciences, Lahore, Pakistan. All of the enrolled animals had no previous experience with freestalls. The selected buffaloes were introduced to the freestall shed. During an adaptation period of 7 d, all buffaloes had 24 h of free access to lie down in 1 of 3 areas: (1) freestalls, (2) alleys, and (3) an outside open area. After the adaptation period, all buffaloes were housed indoors during nighttime (restricted period) to ensure that only freestalls or alleys were available as lying areas. An observer monitored animals at 0100 h and recorded the number of animals lying in freestalls, in alleys, and in the outside open area. The results indicated that during the adaptation period, herd-level freestall occupancy in buffaloes remained below 10%. During the restricted period, herd-level stall occupancy was 0, 13, 50, and 90% on d 1, 2, 5, and 17, respectively. Buffaloes with parity ≥3 took fewer days (6.6 ± 1.0; mean ± standard error of the mean) to occupy stalls than buffaloes with parity 2, 1, and heifers (13.2 ± 1.5, 16.7 ± 2.1, and 13.5 ± 2.1 d, respectively). Body weight and pregnancy status of buffaloes did not have any effect on stall occupancy. Buffaloes showed adjacent stall occupancy, filling opposite stalls first. The results indicated that older buffaloes occupied freestalls earlier than younger buffaloes. Our findings would help better manage buffaloes in freestall housing.     

Characterization of Slag Flow in Fixed Packed Bed of Coke Particles

Metallurgical and Materials Transactions B - The static and dynamic holdups of liquid slag flow in a packed coke bed were investigated at a temperature of 1723 K by using the...