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21.
Food Science and Biotechnology - In this study, yeasts were isolated and characterized from twelve traditional sourdough samples which belongs to Black Sea and Aegean regions of Turkey. Twenty six...  相似文献   
22.
Texas Department of Transportation (TxDOT) currently uses general alternative dispute resolution and dispute management tactics to resolve construction claims. The successful application by TxDOT of project partnering methods, critical path management, and the Contract Claims Committee has resulted in a relatively low number of claims filed. However, one weakness in TxDOT’s current methodology is the lack of specific protocol for project-level personnel and administrators. The following survey of TxDOT dispute resolution methods emphasizes the importance of developing a personnel training catalog for Area Engineers in order to avoid costly claim dispute escalation. As the individual primarily responsible for resolving project and district-level disputes, the Area Engineer should be equipped with dispute resolution training if TxDOT wishes to improve the efficiency of its alternative dispute resolution protocol.  相似文献   
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24.
This paper presents a neural network predictor for analysing rigidity variations of hydrostatic bearing system. The designed neural network has feedforward structure with three layers. The layers are input layer, hidden layer and output layer. Two main parameter could be considered for hydrostatic bearing system. These parameters are the size of bearing pocket and the orifice dimension. Due to importancy of these parameters, it is necessary to analyse with a suitable optimisation method such as neural network. As depicted from the results, the proposed neural predictor exactly follows experimental desired results.  相似文献   
25.
In this study, the effect of CNT amount in Al-CNT composites produced by adding carbon nanotube (CNT) to 7075 Al alloy in various amounts on microstructure and wear behaviors of aluminum matrix composites was investigated. CNT was added to 7075 Al alloy powder at five different amounts. The powders were mechanically milled for 2 hours. Mechanical milled powders were cold pressed and then pre-shaped by hot pressing. Pre-shaped samples were sintered for 1 hour under 10?6 millibar in 580°C. Microstructure examinations, hardness measurements, and wear tests were carried out. The results show that CNT's in the microstructure were agglomerated as nanotube amount increases and there was no uniform distribution. The highest hardness value was obtained in AMC reinforced with 1% CNT while it is seen that hardness of the composite decreases and weight loss increases as CNT amount increases.  相似文献   
26.
The role of impact in the stability of bipedal locomotion   总被引:1,自引:0,他引:1  
A mathematical model of a simple inverted double-pendulum locomotion system was developed. The stability of the nonlinear model was analysed.

Periodic impact of the system with the ground plays a major role in the achievement of stable locomotion. Phase-plane portraits of the generalized coordinates and velocities were utilized to study the behaviour of the system.  相似文献   
27.
In this paper, we study an implicit iterative algorithm for two nonexpansive mappings and two finite families of nonexpansive mappings in Banach spaces. We prove some weak and strong convergence theorems for these iterative algorithms. Our results extend some existing results.  相似文献   
28.
A power amplifier is used to supply sinusoidal currents of different frequencies for measuring eddy-current losses of a 25 kVA single-phase transformer under short-circuit condition. Measured data show that eddy-current loss is a linear function of frequency with power of 2 and the eddy-current loss coefficient PEC-Rlinear is computed. New measurement techniques are applied to determine the derating of single-phase transformers with full-wave diode and thyristor rectifier loads. The derating of transformers has been defined such that for the (apparent, real) power transfer of a transformer the total losses are identical to the rated losses at rated temperature. A relation between apparent power, derating and K-factor is given taking into account iron-core and stray-power losses. Measured derating values are compared with computed results based on the eddy-current losses, iron-core losses, stray-power losses, and K-factors. The eddy-current loss coefficient PEC-Rnonlinear is computed from harmonics caused by diode/thyristor bridge loads  相似文献   
29.
Assignment of military personnel to positions is very demanding, primarily a manual process performed by detailers. Detailers try to satisfy needs and preferences of commands and personnel. In this paper, an analytic hierarchy process (AHP) and two sided matching based Decision Support System is proposed to assist detailers. The DSS is programmed to generate positions’ preferences from position requirement profiles and personnel competence profiles by using analytic hierarchy process and matches personnel to positions by using two-sided matching. The use of the proposed DSS is demonstrated with an example. Also, the effects of preference list length on two-sided matching are examined.  相似文献   
30.
The effect of different amounts of Nb and of homogenization on the ferritic stainless steels containing 17–18 wt.% Cr was investigated with scanning electron microscopy (SEM), optical microscopy, energy-dispersive spectrometry (EDS), X-ray diffraction (XRD) and differential thermal analysis (DTA). It was observed that M23C6, NbC and sigma phase formed in these steels. In addition, the formation of Nb2C was observed in the sample containing 3.0 wt.% Nb. While the amount of Nb increased from 0.5 to 3.0 wt.% Nb, the microhardness of the matrix and the amount of M23C6 decreased and the toughness of the samples increased. After homogenization, the increase in the toughness of the samples containing 1.5–3.0 wt.%Nb was considerable and impressive.  相似文献   
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