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21.
C. Aksu Canbay N. Unlu I. Ozkul T. Polat M. Sekerci K. Aldas 《The Physics of Metals and Metallography》2018,119(6):536-541
Polycrystalline Cu–Al–Ni–Fe-based shape memory alloys with different chemical composition were produced in an arc-melting furnace under an argon atmosphere. Homogenized and aged specimens were prepared for multiple analyses. The temperatures of reversible martensitic transformations, namely As, Af, Ms, Mf, Amax and ΔH enthalpy values were determined by a DSC device. The phase transition analysis from the room temperature to 850°C was undertaken by DTA. To characterize the lattice structure, an XRD analysis was conducted, the results of which were confirmed by microstructure images obtained from optical microscope observations. 相似文献
22.
Nermin Tansuğ Muzaffer Polat Selcan Çeşme Fatma Taneli Salih Gözmen Özlem Tokuşoğlu Dilek Yılmaz Gönül Dinç 《Nutrition journal》2010,9(1):34
Background
Vitamin A deficiency is a major public health nutrition problem in the developing world. Even subclinical Vitamin A deficiency is associated with increased childhood mortality. Severe maternal vitamin A deficiency may cause increased mortality in the first months of life. There have been a limited number of studies regarding vitamin A status in Turkey. The aim of this study was to assess vitamin A status of healthy children in Manisa, Turkey. 相似文献23.
Novel hybrid DNN approaches for speaker verification in emotional and stressful talking environments
Shahin Ismail Nassif Ali Bou Nemmour Nawel Elnagar Ashraf Alhudhaif Adi Polat Kemal 《Neural computing & applications》2021,33(23):16033-16055
Neural Computing and Applications - In this work, we conducted an empirical comparative study of the performance of text-independent speaker verification in emotional and stressful environments.... 相似文献
24.
The assembly line worker assignment and balancing problem type-II (ALWABP-2) occurs when workers and tasks (where task times depend on workers’ skills) are to be simultaneously assigned to a fixed number of workstations with the goal of minimising the cycle time. In this study, a two-phase variable neighbourhood search (VNS) algorithm is proposed to solve the ALWABP-2 due to the NP-hard nature of this problem. In the first phase of the algorithm, a VNS approach is applied to assign tasks to workstations with the aim of minimising the cycle time while in the second phase, a variable neighbourhood descent method is applied to assign workers to workstations. The performance of the proposed algorithm is tested on well-known benchmark instances. In addition, the proposed algorithm has been used to solve a real case study from a consumer electronics company that manufactures LCD TVs. The results show that the algorithm is superior to the methods reported in the literature in terms of its higher efficiency and robustness. Furthermore, the algorithm is easy to implement and significantly improves the performance of the final assembly line for the investigated LCD TV real case study. 相似文献
25.
F Ildan S Polat AI G?cer A Oner T Isbir UO Mete M Kaya A Karadayi 《Canadian Metallurgical Quarterly》1996,138(3):338-345
The sodium-potassium activated and magnesium dependent adenosine-5'-triphosphatase (Na(+)-K(+)/Mg(+2) ATPase EC.3.6.1.3.) activity and lipid peroxidation and early ultrastructural findings were determined in rat brain at the acute stage of ischaemia produced by permanent unilateral occlusion of the middle cerebral artery (MCA). The effects of the pretreatment with intravenous high-dose methylprednisolone (MP) on these biochemical indices and ultrastructural findings were also evaluated in the same model. The rats were divided into four groups. In group I, 10 rats were used to determine Na(+)-K(+)/Mg(+2) ATPase activity and the extent of lipid peroxidation by measuring the malondialdehyde (MDA) content and normal ultrastructural findings. In group II on 20 rats, only subtemporal craniectomy was done in order to determine the effects of the surgical procedure on these indices and findings. This group was treated intravenously with saline solution before occlusion. In group III with MCA occlusion, saline solution was administered intravenously to 20 rats in the same amount of methylprednisolone used in group IV, ten minutes before the occlusion. In Group IV, a single high-dose (30 mg/kg) of methylprednisolone was administered intravenously, ten minutes before occlusion in 20 rats. After occlusion of the middle cerebral artery, Na(+)-K(+)/Mg(+2) ATPase activity was decreased promptly in the first ten minutes in the ischaemic hemisphere and remained at a lower level than the contralateral hemispheres in the same group and the normal levels in group I, during 120 minutes of ischaemia. A single dose methylprednisolone pretreatment prohibited the inactivation of Na(+)-K(+)/Mg(+2) ATPase. On the other hand, there was significant difference in malondialdehyde content between group I and group III. Malondialdehyde levels were significantly increased following ischaemia and a non-significant increase was observed in the contralateral hemisphere. Methylprednisolone treatment significantly decreased malondialdehyde content on the side of the ischaemic hemisphere. We conclude that there is a positive relationship between membrane-bound enzyme Na(+)-K(+)/Mg(+2) ATPase activity, malondialdehyde content and early ultrastructural changes in the treated group with MP. These data suggest that the pretreatment injection of high doses (30 mg/kg) methylprednisolone contribute to the protection of the brain from ischaemia with stabilization of the cell membrane by effecting the lipid peroxidation and the activation of Na(+)-K(+)/Mg(+2) ATPase. 相似文献
26.
BACKGROUND/AIMS: We created a study group in order to investigate the effects of splenectomy and filgrastim. Filgrastim is an immunomodulator granulocyte colony-stimulating factor (G-CSF), that affects bacterial translocation. MATERIALS AND METHODS: We created 3 study groups with 30 male Sprague-Dawley rats; the first group included sham splenectomy, the second group was splenectomy, and the third group was splenectomy+ filgrastim group. RESULTS: The mean bacterial colony count of the cecum were 2.5 x 10(9) in group 1, 1.2 x 10(10) in group 2 and 3.5 x 10(9) in group 3. The differences between these groups were accepted as statistically significant. The mean counts of the terminal ileum were 1.1 x 10(9) in group 1, 5.5 x 10(10) in group 2 and 2.5 x 10(10) in group 3. The p values of group 1-2 were 0.036 (statistically significant) and 0.123 in groups 2-3) were not statistically significant. The mean counts of the liver were 0.2 x 10(4), 1 x 10(10) and 3.4 x 10(5), respectively. In comparison of the groups the p values of the first and last 2 groups were found to be 0.047 (statistically significant). The mean counts of the mesenteric lymph node were 0.7 x 10(3), 1 x 10(10) and 0.9 x 10(6) respectively. The p values were 0.343 for the first and the last 2 groups both. As they were above 0.05, they were not statistically significant. The degrees of liver Kupffer cell hyperplasia were (+) 40%, (+2) 50% and (+3) 10% (group 1), (+) 10%, (+2) 40% and (+3) 50% (group 2), (+2) 60% and (+3) 40% (group 3) (p = 0.0039). The rates of the absence of pathology in mesenteric lymph nodes were 70% (group 1), 90% (group 2) and 100% (group 3) (p = 0.049). These findings were statistically significant. CONCLUSIONS: We found that splenectomy has activated the whole predisposing factors of bacterial translocation and created the latter itself. In addition, we showed that filgrastim, a recently widespread used G-CSF, decreases bacterial translocation significantly. 相似文献
27.
Peggy A. Ertmer Anne T. Ottenbreit-Leftwich Olgun Sadik Emine Sendurur Polat Sendurur 《Computers & Education》2012
Early studies indicated that teachers’ enacted beliefs, particularly in terms of classroom technology practices, often did not align with their espoused beliefs. Researchers concluded this was due, at least in part, to a variety of external barriers that prevented teachers from using technology in ways that aligned more closely with their beliefs. However, many of these barriers (access, support, etc.) have since been eliminated in the majority of schools. This multiple case-study research was designed to revisit the question, “How do the pedagogical beliefs and classroom technology practices of teachers, recognized for their technology uses, align?” 相似文献
28.
29.
Pathfinding algorithms used in todays computer games consider the path length or a similar criterion as the only measure of optimality. However, these games usually involve opposing parties, whose agents can inflict damage on those of the others. Therefore, the shortest path in such games may not always be the safest one. Consequently, a new suboptimal offline path search algorithm based on the A1 algorithm was developed, which takes the threat zones in the game map into consideration. Given an upper limit as the tolerable amount of damage for an agent, this algorithm searches for the shortest path from a starting location to a destination, where the agent may suffer damage less than or equal to the specified limit. Due to its behavior, the algorithm is called Limited-Damage A1 (LDA1). Performance of LDA1 was tested in randomly-generated maze-like grid-based environments of varying sizes, and in hand-crafted fully-observable environments, in which 8-way movement is utilized. Results obtained from LDA1 are compared with those obtained from Multiobjective A1 (MOA1), which is a complete and optimal algorithm that yields exact (best) solutions for every case. LDA1 was found to perform much faster than MOA1, yielding acceptable sub-optimality in path length. 相似文献
30.
Turkey is classified among the countries which have a high geothermal energy potential (Alpan, 1974). Geological and geophysical exploration is continuing in promising areas. However primary emphasis has been given to Western Anatolia during the last decade. As a result of these efforts Kizildere field was developed and a power plant put into operation on February 14, 1984. This paper summarizes the power plant and production problems encountered in wells during 1984 and future field development plans. 相似文献