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131.
Alacaoglu Ahmet Malitsky Yura Cevher Volkan 《Computational Optimization and Applications》2021,80(2):321-346
Computational Optimization and Applications - We propose a variance reduced algorithm for solving monotone variational inequalities. Without assuming strong monotonicity, cocoercivity, or... 相似文献
132.
Hierarchical problem solving is preferred when the problem is overwhelmingly complicated. In such a case, the problem should
better be analyzed in hierarchical levels. At each level, some temporary solutions are obtained; then a suitable decision
fusion technique is used to merge the temporary solutions for the next level. The hierarchical framework proposed in this
study depends on reutilization or elimination of previous level local agents that together perform the decisions due to a
decision-fusion technique: a performance criterion is set for local agents. The criterion checks the success of agents in
their local regions. An agent satisfying this criterion is reutilized in the next level, whereas an agent not successful enough
is removed from the agent pool in the next level. In place of a removed agent, a number of new local agents are developed.
This framework is applied on a fault detection problem.
相似文献
133.
The proposed decision model, based on Analytic Network Process (ANP), has been developed in order to determine the dynamics
of the Global System for Mobile Communications (GSM) market. In accordance with the sequence of ANP, first of all, the problem
was structured and modeled. At the next step, a quantitative analysis was conducted with the customers in order to assess
the importance of the related factors and forecast the market shares of the Turkish mobile communication operators. The forecasted
market share values were compared with actual ones for the validation of the decision model. The assessed importance of the
factors in a valid model would be a potential competitive advantage for the mobile operators. 相似文献
134.
135.
Burak Guzelturk Pedro Ludwig Hernandez Martinez Qing Zhang Qihua Xiong Handong Sun Xiao Wei Sun Alexander O. Govorov Hilmi Volkan Demir 《Laser \u0026amp; Photonics Reviews》2014,8(1):73-93
In the past two decades, semiconductor quantum dots and wires have developed into new, promising classes of materials for next‐generation lighting and display systems due to their superior optical properties. In particular, exciton–exciton interactions through nonradiative energy transfer in hybrid systems of these quantum‐confined structures have enabled exciting possibilities in light generation. This review focuses on the excitonics of such quantum dot and wire emitters, particularly transfer of the excitons in the complex media of the quantum dots and wires. Mastering excitonic interactions in low‐dimensional systems is essential for the development of better light sources, e.g., high‐efficiency, high‐quality white‐light generation; wide‐range color tuning; and high‐purity color generation. In addition, introducing plasmon coupling provides the ability to amplify emission in specially designed exciton–plasmon nanostructures and also to exceed the Förster limit in excitonic interactions. In this respect, new routes to control excitonic pathways are reviewed in this paper. The review further discusses research opportunities and challenges in the quantum dot and wire excitonics with a future outlook. 相似文献
136.
Gulmira Özek Fatih Demirci Temel Özek Nurhayat Tabanca David E. Wedge Shabana I. Khan Kemal Hüsnü Can Başer Ahmet Duran Ergin Hamzaoglu 《Journal of chromatography. A》2010,1217(5):741-748
Four different isolation techniques, conventional hydrodistillation (HD), microwave-assisted hydrodistillation (MWHD), microdistillation (MD) and micro-steam distillation-solid-phase microextraction (MSD-SPME), have been used to analyze the volatile constituents from the aerial parts of Salvia rosifolia Sm. by gas chromatography and gas chromatography coupled to mass spectrometry. HD and MWHD techniques produced quantitatively (yield, 0.39% and 0.40%) and qualitatively (aromatic profile) similar essential oils. α-Pinene (15.7–34.8%), 1,8-cineole (16.6–25.1%), β-pinene (6.7–13.5%), β-caryophyllene (1.4–5.0%) and caryophyllene oxide (1.4–4.4%) were identified as major constituents of this Turkish endemic species. Besides, the hydrodistilled oil of S. rosifolia was evaluated for antibacterial, antifungal, anticancer, antioxidant and cytotoxic activities. The hydrodistilled oil of S. rosifolia showed antibacterial activity against Methicillin-resistant Staphylococcus aureus (MRSA) with a MIC value of 125 μg/mL. Other human pathogenic microorganisms (Escherichia coli, Pseudomonas aeruginosa, Enterobacter aerogenes, Salmonella typhimurium, Staphylococcus epidermidis, Candida albicans) were also inhibited within a moderate range (MIC = 125–1000 μg/mL). Antifungal activity of the oil was also observed against the strawberry anthracnose-causing fungal plant pathogens Colletotrichum acutatum, C. fragariae and C. gloeosporioides. No cytotoxicity was observed for S. rosifolia oil up to 25 mg/mL against malignant melanoma, epidermal, ductal and ovary carcinoma. 相似文献
137.
Kemal Sancak Yasemin Ünver Hasan Tanak Ismail Değirmencioğlu Esra Dügdü Mustafa Er Şamil Işik 《Journal of inclusion phenomena and macrocyclic chemistry》2010,67(3-4):325-334
A series of new N′-3-(1H-imidazol-1-yl)propylcarbamoyl-4-halogenebenzo hydrazonate (3a–b) were obtained by reaction Ethyl 2-((4-halogene phenyl) (ethoxy) methylene) hydrazinecarboxylate (1) and N-(3-aminopropyl)imidazole (2) at 120–140 °C. Compounds (4a–b) were obtained by the reaction compound 1 and N-(3-aminopropyl)imidazole (2) at 160–180 °C. The structures of compounds 3,4 have been inferred through UV–Vis, IR, 1H/13C NMR, mass spectrometry, elemental analyses, and X-ray crystallography. DFT level 6-31G (d) calculations provided structural information. The electronic structure of compound 3a has been studied by DFT level 6-31G (d) calculations using the X-ray data. The results are accordance with X-ray data. 相似文献
138.
Isabelle Maraval Kemal Sen Chantal Menut Renaud Boulanger Christian Mestres 《Analytica chimica acta》2010,675(2):148-155
A new and convenient synthesis of 2-acetyl-1-pyrroline (2AP), a potent flavor compound in rice, and its ring-deuterated analog, 2-acetyl-1-d2-pyrroline (2AP-d2), was reported. A stable isotope dilution assay (SIDA), involving headspace solid-phase microextraction (HS-SPME) combined with gas chromatography-positive chemical ionization-ion trap-tandem mass spectrometry (GC-PCI-IT-MS-MS), was developed for 2AP quantification. A divinylbenzene/carboxen/polydimethylsiloxane (DVB/CAR/PDMS) fiber was used for HS-SPME procedure and parameters affecting analytes recovery, such as extraction time and temperature, pH and salt, were studied. The repeatability of the method (n = 10) expressed as relative standard deviation (RSD) was 11.6%. A good linearity was observed from 5.9 to 779 ng of 2AP (r2 = 0.9989). Limits of detection (LOD) and quantification (LOQ) for 2AP were 0.1 and 0.4 ng g−1 of rice, respectively. The recovery of spiked 2AP from rice matrix was almost complete. The developed method was applied to the quantification of 2AP in aerial parts and grains of scented and non-scented rice cultivars. 相似文献
139.
Effects of flow oscillations on spectrum of Ultrasound Doppler Velocimetry (UDV) signals were investigated theoretically and numerically. A laminar pipe flow with a superimposed oscillating component was considered. Negative impact of oscillation on the ultrasound signal hence on the flow images was observed in the form of spreading of spectral ultrasound signal energy around mean component, leading to image artifacts. Both analytical and numerical results revealed the strong effect of a group of parameters including Doppler frequency, flow oscillation amplitude and frequency. Exceeding a particular value of the group, 1.45, resulted in artifacts in the flow images. Revealing the mechanisms involved in the deteriorations associated with the flow oscillations is potentially useful in UDV studies involving random flow fluctuations such as turbulence. 相似文献
140.
Jiao Z Wang X Wang J Ke L Demir HV Koh TW Sun XW 《Chemical communications (Cambridge, England)》2012,48(3):365-367
Plate-like hydrated tungsten trioxide (3WO(3)·H(2)O) films were grown on a fluorine doped tin oxide (FTO) coated transparent conductive substrate via an efficient, facile and template-free hydrothermal method. The film exhibited a fast coloration/bleaching response (t(c90%) = 4.3 s and t(b90%) = 1.4 s) and a high coloration efficiency (112.7 cm(2) C(-1)), which were probably due to a large surface area. 相似文献