Real-time path planning for autonomous vehicle based on teaching–learning-based optimization

Intelligent Service Robotics - This paper presents an online path planning approach for an autonomous tracked vehicle in a cluttered environment based on teaching–learning-based optimization...     

Nanocrystalline β-γ-β cyclic phase transformation in reacted ball milled MgH2 powders

Pure magnesium powders were ball milled under a hydrogen pressure of 50 bar at room temperature, using reactive ball milling (RBM) approach. The results have shown that a single stable phase of β-MgH₂ is obtained upon RBM for 25 h. Increasing the RBM time leads to a significant decreasing on the grain size and an increase in the iron contamination that were introduced to the powders upon using hard steel milling tools. Remarkable changes in the transformed mass fractions of β-MgH₂ phase to a metastable γ-MgH₂ phase with increasing the RBM time could be detected. Cyclic β-γ-β phase transformations were observed several times upon changing the RBM time. After 200 h of RBM time, the decomposition temperature and activation energy were recorded to be 399 °C and 131 kJ/mol, respectively. Moreover, the times required for complete absorption and desorption of 7 wt.% of hydrogen at 250 °C were recorded to be 3140 s and 35,207 s under 10 and 0 bar, respectively. At 300 °C, the powders that were obtained upon RBM time for 200 h possess excellent hydrogenation properties for any pure MgH₂ system, indexed by high hydrogen storage capacity (7.54 wt.%) with complete 600 absorption/desorption cycles. Improvements of hydrogenation/dehydrogenation kinetics are attributed to the presence of γ-phase, the existence of Fe contamination and the nanocrystallinity of the ball milled powders.     

Prevalence of Listeria spp. and antibiotic susceptibility of Listeria monocytogenes isolated from raw chicken and ready-to-eat chicken products in Jordan

Listeria monocytogenes is the causal agent of listeriosis, a disease that can be serious and is often fatal in susceptible individuals. The objective of the study was to determine the prevalence of Listeria spp. in raw chicken and ready-to-eat (RTE) chicken products in Amman, Jordan and the antimicrobial resistance of L. monocytogenes isolates. A total of 280 raw chicken and RTE chicken products (chicken-shawirma, chicken-burger, chicken-sausage and mortadella) were collected from Amman abattoir and local retail markets in Amman city. Listeria spp. were isolated by the conventional International Organization for Standardization (ISO) method and L. monocytogenes identified by biochemical and Polymerase Chain Reaction (PCR). Results of conventional method showed that out of total 280 samples, 141 (50%) were found to be contaminated with Listeria spp. [L. monocytogenes (18.2%), Listeria ivanovi (26.1%), Listeria grayi (3.5%), Listeria seeligeri (1.8), Listeria welshimeri (0.7%)]. The PCR confirmed all L. monocytogenes isolates (51 isolates: 15 from raw dressed broiler chicken, 23 from chicken-burger, 9 from chicken-sausage, and 4 from chicken-shawirma). Five of the tested L. monocytogenes isolates were resistance to two antibiotics (tilimicosin and tetracycline) among the ten tested antibiotics as determined by microbroth dilution method. The results presented in this study indicate the potential risk of contamination of RTE chicken products with L. monocytogenes.     

Effect of gamma irradiation on the color properties of synthetic fabrics dyed by arylazo-pyrazolone disperse dyes

Two derivatives of 3-amino-4-arylazo-1-phenylpyrazol-5-one have been used for dyeing un-irradiated and irradiated polyester and nylon fabrics using different absorbed doses of Co-60 gamma irradiation to study the effect of radiation treatment on the color strength of dyed fabrics. The data color report is used for the evaluation of un-irradiated and irradiated dyed polyester and nylon using GretagMacbeth spectrophotometer (CE 7000a) in CIE Lab system. The color strength K/S of the dyed polyester and nylon fabrics was increased by increasing the absorbed dose to 80 kGy. It is found that gamma irradiation has a potential to improve the fastness properties such as light, rubbing, perspiration, and washing.     

Numerical simulation of biodiesel fuel combustion and emission characteristics in a direct injection diesel engine

The effect of the physical and chemical properties of biodiesel fuels on the combustion process and pollutants formation in Direct Injection (DI) engine are investigated numerically by using multi-dimensional Computational Fluid Dynamics (CFD) simulation. In the current study, methyl butanoate (MB) and n-heptane are used as the surrogates for the biodiesel fuel and the conventional diesel fuel. Detailed kinetic chemical mechanisms for MB and n-heptane are implemented to simulate the combustion process. It is shown that the differences in the chemical properties between the biodiesel fuel and the diesel fuel affect the whole combustion process more significantly than the differences in the physical properties. While the variations of both the chemical and the physical properties between the biodiesel and diesel fuel influence the soot formation at the equivalent level, the variations in the chemical properties play a crucial role in the NO_x emissions formation.     

Behavior of CFRP Strengthened Reinforced Concrete Beams in Corrosive Environment

This paper reports the test results of 11 reinforced concrete beams strengthened with carbon fiber-reinforced polymer (CFRP) sheets and subjected to an aggressive environment. In this study, eight beams were cracked and repaired with CFRP sheets, while the remaining three beams were kept uncracked as a control. The beams were 150?mm wide by 250?mm deep by 2,400?mm long and lightly reinforced with a reinforcement ratio of 0.6%. Two types of carbon FRP products were considered: Sheets and strips. In terms of environmental exposure, three beams were kept at room temperature and eight beams were subjected up to 300 wetting and drying cycles with deicing chemicals (3% NaCl). Following the exposure, the beams were tested to failure in four-point bending. In addition, nondestructive tests were performed to determine the corrosion rate, as well as destructive tests to determine chloride diffusion and reinforcing bar mass loss. Based on the findings of the study, the long-term effectiveness of the CFRP strengthened reinforced concrete in aggressive corrosive environments was established.     

QoS Path Monitoring for Multicast Networks

New network monitoring tools are necessary for supporting the deployment and the operations of multicast services on the Internet. Because of the peculiar characteristics of multicast routing (e.g., multicast forwarding trees) and the potential of message implosion problems, traditional network management tools are not sufficient for monitoring the quality of multicast delivery such as packet loss, delay, and jitter. Current multicast monitoring tools are either not scalable, limited in their functionality, or difficult to deploy in enterprise networks.In this paper, we present a new monitoring framework (called SMRM, SNMP-based multicast reachability monitoring) for multicast reachability based on SNMP. The SMRM framework is used for actively monitoring the health and the quality of service of multicast networks. SMRM provides a scalable real-time feedback on the packet loss, delay, and jitter of any selected segments of multicast delivery trees. In addition, NOC (network operations center) personnel can easily understand, deploy, and extend the SMRM framework in order to detect and isolate reachability and performance problems in multicast sessions. SMRM combines both distributed monitoring and centralized control, which offers scalability and simplicity. The integration of SMRM into SNMP is motivated by the wide distribution of SNMP agents in networks today, which significantly facilitates the deployment of SMRM is existing networks.     

Laboratory Measurements of Flow through Culverts

Laboratory apparatus to simulate flow through culverts has been used to collect discharge and water level measurements. Two different shapes of culvert barrels, namely square and circular, were tested. The measurements presented in this note are intended to provide useful information regarding the variety of flow regimes (including overtopping) through culverts, and the transitions from one flow regime to another. It is known that modeling the culvert flow regimes and capturing the transitions among these regimes numerically is a challenging task. To that effect, the laboratory measurements presented herein can provide a testing and validation data set for numerical modeling of hydraulic structures such as culverts.     

Effect of cooking on tryptophan,basic amino acids,protein solubility and retention of some vitamins in two varieties of chick pea

Egyptian and Italian varieties of chick pea were analysed chemically to study their total constituents. The two varieties were cooked for 1 and 2 h and autoclaved for 1 h at 121°C. Their constituent basic amino acids, tryptophan, thiamin, pyridoxin and niacin, were determined.There were differences in the chemical constituents between the two varieties. Cooking decreased lysine, histidine and arginine, the effect being highly significant. Tryptophan decreased, the effect being significant. In addition, protein solubility decreased with increased cooking time.The vitamin content also decreased with increased cooking time. It is preferable to cook chick pea in an autoclave at 121°C for not more than 1 h to minimise losses in vitamins and amino acids.     

Amino acid composition of two Italian durum wheat varieties and their semolina

Two Italian durum wheat varieties and their semolina were analysed for protein content and amino acid composition. There was a difference in protein content between the two varieties. The concentration (in protein) of lysine, methionine and phenyl alanine was equal in both varieties. A large difference was found in glutamic acid and valine. A slight difference was found in other amino acids. There was a difference in the concentration of amino acids between wheat and its semolina. The biological value was equal in both varieties. The difference in results is attributed to the varietal difference.