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排序方式: 共有213条查询结果,搜索用时 15 毫秒
1.
Electroinitiated cationic copolymerisation of indene and styrene was investigated by constant potential electrolysis. Effects of copolymerisation potential and temperature on the copolymer composition and the reactivity ratios are discussed. The reactivity ratios of the monomers were calculated according to the integrated Lewis-Mayo equation.  相似文献   
2.
Fuzzy rule-based systems have been very popular in many engineering applications. In mineral engineering, fuzzy rules are normally constructed using some fuzzy rule extraction techniques to establish the determination model in predicting the d50c of hydrocyclones. However, when generating fuzzy rules from the available information, it may result in a sparse fuzzy rule base. The use of more than one input variable is also common in hydrocyclone data analysis. This paper examines the application of fuzzy interpolation to resolve the problems using sparse fuzzy rule bases, and to perform analysis of fuzzy interpolation in multidimensional input spaces.  相似文献   
3.
Kocak  Cem  Egrioglu  Erol  Bas  Eren 《The Journal of supercomputing》2021,77(6):6178-6196
The Journal of Supercomputing - In recent years, deep artificial neural networks can have better forecasting performance than many other artificial neural networks. The long short-term memory...  相似文献   
4.
Fuzzy time series approaches are used when observations of time series contain uncertainty. Moreover, these approaches do not require the assumptions needed for traditional time series approaches. Generally, fuzzy time series methods consist of three stages, namely, fuzzification, determination of fuzzy relations, and defuzzification. Artificial intelligence algorithms are frequently used in these stages with genetic algorithms being the most popular of these algorithms owing to their rich operators and good performance. However, the mutation operator of a GA may cause some negative results in the solution set. Thus, we propose a modified genetic algorithm to find optimal interval lengths and control the effects of the mutation operator. The results of applying our new approach to real datasets show superior forecasting performance when compared with those obtained by other techniques.  相似文献   
5.
Yılmaz  Oguzhan  Bas  Eren  Egrioglu  Erol 《Computational Economics》2022,59(4):1699-1711
Computational Economics - Looking at the artificial neural networks’ literature, most of the studies started with feedforward artificial neural networks and the training of many feedforward...  相似文献   
6.
(1) Background: Placental immune cells are playing a very important role in a successful placentation and the prevention of pregnancy complications. Macrophages dominate in number and relevance in the maternal and the fetal part of the placenta. The evidence on the polarization state of fetal and maternal macrophages involved in both, healthy and pregnancy-associated diseases, is limited. There is no representative isolation method for the direct comparison of maternal and fetal macrophages so far. (2) Material and Methods: For the isolation of decidual macrophages and Hofbauer cells from term placenta, fresh tissue was mechanically dissected and digested with trypsin and collagenase A. Afterwards cell enrichment was increased by a Percoll gradient. CD68 is represented as pan-macrophage marker, the surface markers CD80 and CD163 were further investigated. (3) Results: The established method revealed a high cell yield and purity of the isolated macrophages and enabled the comparison between decidual macrophages and Hofbauer cells. No significant difference was observed in the percentage of single CD163+ cells in the distinct macrophage populations, by using FACS and immunofluorescence staining. A slight increase of CD80+ cells could be found in the decidual macrophages. Considering the percentage of CD80+CD163 and CD80CD163+ cells we could not find differences. Interestingly we found an increased number of double positive cells (CD80+CD163+) in the decidual macrophage population in comparison to Hofbauer cells. (4) Conclusion: In this study we demonstrate that our established isolation method enables the investigation of decidual macrophages and Hofbauer cells in the placenta. It represents a promising method for direct cell comparison, enzyme independently, and unaffected by magnetic beads, to understand the functional subsets of placental macrophages and to identify therapeutic targets of pregnancy associated diseases.  相似文献   
7.
Objectives: The aim of this in vitro study was to evaluate the effect of different desensitizers’ application on the microleakage of previously restored Class V composite resin restorations.

Materials and methods: Class V cavities were prepared on the buccal surfaces of 40 extracted human third molars. Forty box-shaped cavities were divided into four groups, based on the desensitizers used (n = 10). All teeth were restored with the same bonding agent and composite material. No desensitizer was applied in the control group. In the experimental groups, BisBlock, Gluma and Universal bonding agents were the desensitizers. The desensitizers were applied after completion of composite restorations according to manufacturers’ instructions. All specimens were then thermocycled at 5–55 °C, with a 10-s dwell time for 500 cycles. The samples were then immersed in 0.5% methylene blue dye for 24 h, sectioned into two equal halves, evaluated for microleakage using a stereomicroscope at 30× magnification and scored on a scale of 0–3. The data were analysed using the Kruskal–Wallis test at the significance level p < 0.05.

Results: There were no significant differences in microleakage after desensitizer application (p > 0.05). However, based on the obtained numerical values in our study, while the BisBlock and bonding groups showed lower microleakage at the occlusal margin, BisBlock, Gluma and bonding group showed lower microleakage at the gingival margin compared to the control group.

Conclusions: The application of desensitizers as a post-treatment option could be considered an advisable procedure to minimize microleakage.  相似文献   

8.
In this study, methyl oleate was bromoacrylated in the presence of N‐bromosuccinimide and acrylic acid in one step. Homopolymers and copolymers of bromoacrylated methyl oleate (BAMO) were synthesized by free radical bulk polymerization and photopolymerization techniques. Azobisisobutyronitrile (AIBN) and 2,2‐dimethoxy‐2‐phenyl‐acetophenone were used as initiators. The new monomer BAMO was characterized by FTIR, GC‐MS, 1H, and 13C‐NMR spectroscopy. Styrene (STY), methylmethacrylate (MMA), and vinyl acetate (VA) were used for copolymerization. The polymers synthesized were characterized by FTIR, 1H‐NMR, 13C‐NMR, and differential scanning calorimetry (DSC). Molecular weight and polydispersities of the copolymers were determined by GPC analysis. Ten different feed ratios of the monomers STY and BAMO were used for the calculation of reactivity ratios. The reactivity ratios were determined by the Fineman–Ross and Kelen–Tudos methods using 1H‐NMR spectroscopic data. The reactivity ratios were found to be rsty = 0.891 (Fineman–Ross method), 0.859 (Kelen–Tudos method); rbamo = 0.671 (Fineman–Ross method), 0.524 (Kelen–Tudos method). © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 2475–2488, 2004  相似文献   
9.
10.
The consumer decision process is a widely accepted model covering consumer activities, and accordingly contains five interrelated stages: problem recognition, information search, evaluation of alternatives, purchase, and post-purchase evaluation. In order to help consumers deal with challenges associated with all these stages, mobile information systems bring significant capabilities, as in other application domains. However, related prior research is mostly restricted to the individual stages of the process. Since the stages are interrelated, and the data collected in one are also valuable for another, we propose a mobile framework designed to provide assistance in all stages of the Consumer Decision Process, named MobileCDP. A prototype is also implemented and evaluated to show the applicability of the framework. Experiments show that the functions provided by the prototype are useful, well integrated, and easy to use. Moreover, statistical analysis of the results proves that the prototype reduces time, costs, and cognitive effort of the user.  相似文献   
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