Evaluation of trace metal contents of some wild edible mushrooms from Black sea region, Turkey

Fructification organs of Calvatia excipuliformis, Lycoperdon perlatum, Laccaria amethystea, Armillaria mellea, Marasmius oreades, Xerula radicata, Cantharellus cibarius, Craterellus cornucopioides, Cantharellus tubaeformis, Hypholoma fasciculare, Clitocybe gibba, Collybia dryophila, Lepista nuda and Mycena aetites were collected from different localities in Black sea region of Turkey. Their trace metals concentrations were determined by atomic absorption spectrometry after wet and microwave digestion. The results were (as mg/kg) 150–1741 for iron, 15.5–73.8 for copper, 28.6–145 for manganese, 43.5–205 for zinc, 4.8–42.7 for aluminium and 0.9–2.6 for lead. The levels of lead analyzed in some edible mushroom samples were found to be higher than legal limits. The relative standard deviations (R.S.D.) were found below 10%. The accuracy of procedure was confirmed by certified reference material.     

Prediction of manually controlled vessels’ position and course navigating in narrow waterways using Artificial Neural Networks

Despite modern navigation devices, there are still some problems for navigating of vessels in narrow waterways because of geographical structures and various disturbances. In this study, a guidance and an early warning method by means of predicting three-minute-ahead position of a vessel, especially in the turning points, has been developed for navigating in narrow waterways. The Istanbul Strait has been specifically studied as a model. Since operators in Vessel Traffic Services (VTS) can watch only straight bearing of vessels on VTS panels but especially for turning regions, they have to foresee a risk on time which may result in a disaster. The objective of this study is to predict the future coordinates of a manually controlled vessel using Artificial Neural Networks (ANN).Artificial Neural Networks have been trained by using position and speed data collected from vessels which navigated manually in the Strait. Three-minute-ahead position of vessels has been predicted by using the trained ANN. Some on-line experiments have been done in Istanbul VTS centre and it has been observed that the method satisfied the goal in especially turning points of the Strait. Hence the proposed method could be utilized for warning system by VTS operators and guidance system by vessel crew.     

In situ mullite foam fabrication using microwave energy

In situ mullite ceramic foams were fabricated using polymeric sponge replication method from ceramic slurry containing alpha alumina and kaolin mixtures. Ceramic preforms were processed using microwave energy and conventional heating. The sintered foam samples were characterized by SEM and XRD observations, density measurements and compression tests in order to observe the effect of two different sintering techniques on the structure and properties. It was found that the microwave processing was completed in a shorter burning out and sintering cycle and produced structures having higher mullite transformation ratio and fine grains.     

Iron Loss Reduction in an Interior PM Automotive Alternator

This paper examines the iron loss characteristics of a high-flux interior permanent-magnet machine. The machine was designed as a concept demonstrator for a 6-kW automotive alternator and has a wide field-weakening range. Initial experimental results revealed a high iron loss during field-weakening operation. Finite-element analysis was used to investigate the cause of the high iron losses and to predict their magnitude as a function of speed. The effects of changes in the machine design were examined in order to reduce iron losses and hence improve the machine performance     

Improved common weight MCDM model for technology selection

This paper presents an improvement on earlier work on a common weight multi-criteria decision-making (MCDM) approach for technology selection by (Karsak, E.E. and Ahiska, S.S., Practical common weight multi-criteria decision-making approach with an improved discriminating power for technology selection. Int. J. Prod. Res., 2005, 43, 1537–1554.) benefiting from a bisection search algorithm. The proposed algorithm enables to calculate the values of discriminating parameter, k, which appears in the introduced efficiency measure, in a systematic and robust manner rather than requiring the decision analyst to assign an arbitrary step size value. In addition, the paper presents comments on the model proposed by (Amin, G.R., Toloo, M. and Sohrabis, B., An improved MCDM DEA model for technology selection. Int. J. Prod. Res., 2006, 44, 2681–2686.) for technology selection. Finally, the robustness of the proposed decision-making framework is illustrated via several numerical examples taken from the above-mentioned papers.     

Indirect angle estimation in switched reluctance motor drive usingfuzzy logic based motor model

In this paper, a novel rotor position estimation scheme is described that was developed to overcome the drawbacks of the previous sensorless techniques, which were proposed for switched reluctance (SR) motor drives. It is based on fuzzy-logic, and does not require complex mathematical models or large look up tables. The scheme was implemented by using a digital signal processor. The real-time experimental results given in this paper show that the position estimation method proposed can provide accurate and continual position data over a wide range of speeds (zero/low/high), and can also function accurately at different operating conditions (chopping/single pulse mode and steady state/transient operation)     

Dynamic behavior of the flow field in a RIM machine mixing chamber

Dynamic behavior of the flow field in a Reaction Injection Molding, RIM, machine mixing chamber, having dimensions typically used in industrial machines, is studied from dynamic velocity data of Laser Doppler Anemometry, LDA, measurements and Computational Fluid Dynamics, CFD, simulations with a 2D model. This study is based on the spectral analysis of the dynamic flow field data. The typical frequencies, in the reactor flow field, are identified and its values are related to the identified flow structures. The differences between the typical frequencies from experiments and simulations are observed and justified on the basis of the 2D representation of a 3D cylindrical geometry. © 2009 American Institute of Chemical Engineers AIChE J, 2009     

Uncontrolled generation in interior permanent-magnet Machines

The movement toward higher power automotive electrical systems has spurred research into low-cost alternators capable of operating over a wide constant-power speed range. A promising candidate for this application is a specially designed interior permanent-magnet (IPM) machine operating in uncontrolled generation (UCG). This paper investigates the modeling and performance of IPM machines in UCG. The concept of the voltage-current locus is introduced to explain the presence of hysteresis in the machine stator current and this effect is experimentally demonstrated. The effect of nonidealities such as magnetic saturation and stator resistance are also examined, to achieve a more accurate steady-state and dynamic modeling of the machine behavior. The predictions of these models are tested against experimental results.     

Microwave coaxial slot bridge technique for the dielectric parameter control of liquids

The basic physical principles and construction of the device for investigation of dielectric parameters of liquids are considered. The key moment is in the using of the rigorous solution of initial boundary value problem for the resonant electromagnetic structure that is in the focus of the device. Thus all electromagnetic characteristics are calculated with the required accuracy and several rather special phenomena are taken into account.