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71.
Scientometrics - This article illustrates different information visualization techniques applied to a database of classical composers and visualizes both the macrocosm of the Common Practice Period... 相似文献
72.
K‐Nearest neighbor (K‐NN) algorithm is a classification algorithm widely used in machine learning, statistical pattern recognition, data mining, etc. Ordered weighted averaging (OWA) distance based CxK nearest neighbor algorithm is a kind of K‐NN algorithm based on OWA distance. In this study, the aim is two‐fold: i) to perform the algorithm with two different fuzzy metric measures, which are Diamond distance, and weighted dissimilarity measure composed by spread distances and center distances, and ii) to evaluate the effects of different metric measures. K neighbors are searched for each class, and OWA distance is used to aggregate the information. The OWA distance can behave as intercluster distance approaches single, complete, and average linkages by using different weights. The experimental study is performed on well‐known three classification data sets (iris, glass, and wine). N‐fold cross‐validation is used for the evaluation of performances. It is seen that single linkage approach by using two different metric measures has significant different results. 相似文献
73.
ABSTRACTIn this paper, experiments have been performed to further the development of conductivity of the polyethylene. This study mainly investigated the surface resistivity and surface wettability of the polyethylene (PE) after ionic liquid modifications. In order to activate the surface, PE was pre-treated with chromic acid and then modified with 1-ethyl-2,3-dimethylimidazolium ethyl sulfate (IL1) and methyl-tri-n-butylammonium methyl sulfate (IL2) ionic liquids. The effect of the type and concentration of the ionic liquid IL1 and IL2 concentrations is examined by Fourier Transform Infrared (FTIR), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), scanning electron microscopy (SEM), surface resistivity and surface wettability. Results showed that thermal stability of the PE deteriorated after ionic liquid modifications. Both untreated and modified fabrics exhibited resembling crystallinity parameters. Nearly 57% enhancement in surface wettability of the PE was achieved. The pre-treatment process decreased the surface resistivity and increased surface wettability of the PE. The main success in this research is that IL1 and IL2 modifications reduced the resistivity data from 1011 ohm/sq to 107 ohm/sq and 108 ohm/sq, respectively. 相似文献
74.
In this study, the gemini surfactants of the alkanediyl-α-ω-bis(alkyl dimethyl ammonium) dibromide type, on the one hand,
with different alkyl groups containing m carbon atoms and an ethanediyl spacer, referred to as “m-2-m” (m = 10, 12 and 16)
and, on the other hand, with n-C16 alkyl groups and different spacers containing s carbon atoms, referred to as “16-s-16” (s = 2, 6, 10 and Ar (8)) have been
synthesized, purified and characterized. The critical micelle concentration (CMC), micelle ionization degree (α) and Gibbs
free energy of micellization (∆G
mic) of these surfactants and the monomeric cationic surfactants DTAB and CTAB have been determined by means of electric conductivity
measurements. In addition, the temperature dependence of the CMC was determined for the 10-2-10 gemini surfactant. The CMCs
of the gemini surfactants are found to be much lower than those of the corresponding monomeric surfactants and the effect
of the hydrophobic alkyl chain length is more important than that of the spacer. The CMC of 16-s-16 passes through a maximum
of (or around) s = 6 and then decreases for s = 10. The presence of a maximum CMC is explained by the contribution of a change
of conformation of the surfactant with increasing spacer chain length. The changes of α with s and m are found qualitatively
similar to those found for CMC values. The values of ∆G
mic are more negative for the dimers than for the monomers and also change with an increasing spacer carbon number, as CMC values
do. The thermodynamic parameters of micellization indicate that the micellization of 10-2-10 is enthalpy driven. 相似文献
75.
Nutritional properties and health aspects of pulses and their use in plant-based yogurt alternatives
Theresa Boeck Aylin W. Sahin Emanuele Zannini Elke K. Arendt 《Comprehensive Reviews in Food Science and Food Safety》2021,20(4):3858-3880
Plant-based yogurt alternatives are increasing in market value, while dairy yogurt sales are stagnating or even declining. The plant-based yogurt alternatives market is currently dominated by products based on coconut or soy. Coconut-based products especially are often low in protein and high in saturated fat, while soy products raise consumer concerns regarding genetically modified soybeans, and soy allergies are common. Pulses are ideally suited as a base for plant-based yogurt alternatives due to their high protein content and beneficial amino acid composition. This review provides an overview of pulse nutrients, pro-nutritional and anti-nutritional compounds, how their composition can be altered by fermentation, and the chemistry behind pulse protein coagulation by acid or salt denaturation. An extensive market review on plant-based yogurt alternatives provides an overview of the current worldwide market situation. It shows that pulses are ideal base ingredients for yogurt alternatives due to their high protein content, amino acid composition, and gelling behavior when fermented with lactic acid bacteria. Additionally, fermentation can be used to reduce anti-nutrients such as α-galactosides and vicine or trypsin inhibitors, further increasing the nutritional value of pulse-based yogurt alternatives. 相似文献
76.
In this paper, we present an Analytical Network Process (ANP) model to determine the best fuel mix for electricity generation in Turkey from a sustainable development perspective. The proposed model is implemented in two alternative scenarios. These scenarios are structured along the lines of classification between weak and strong sustainability, and therefore reflect two basic dimensions of sustainability of energy production—environmental protection and sustainable supply of energy resources. The results of the study indicate the gap between goals of sustainable development and energy policies of Turkey in terms of energy security and environmental degradation. Under all alternative scenarios of our model, the highest value alternative is hydropower—domestic, renewable source—while the Turkish electricity sector mainly relies on imported natural gas. The share of nuclear energy is in the range of 8.12–10.21% in our model results, although nuclear energy is not available yet. The calculated percentages of renewable fuels (biomass, geothermal, wind, solar) are 35.7% and 28.9% for Scenario 1 and Scenario 2, respectively, while the total percentage of these fuels is 0.18% of the installed capacity of Turkey. The results of our model suggest that the share of renewable fuels in installed capacity should be increased to achieve sustainable development. 相似文献
77.
In this study, production of pomegranate juice powder using a spray dryer was investigated. To prevent stickiness, maltodextrin dextrose equivalent 6 (DE6) was used as a drying agent. While feed flow rate, feed temperature, and air flow rate were kept constant, air inlet temperature (110–140°C), percentage maltodextrin (MD; maltodextrin dry solids/100 g feed mixture dry solids; 39.08–64.12%), and feed mixture concentration (19.61–44.11 °Brix) were chosen as the independent variables. Product properties investigated included moisture content, hygroscopicity, anthocyanin content, color change, solubility, bulk density, total phenolics content, antioxidant capacity, and sensory properties. The products were produced with high yield (86%) and high antioxidant activity (77%). MD and drying temperature were found to be the most important variables in production of pomegranate juice powders. Because total color change (ΔE), bulk density, antioxidant capacity, and powder yield were affected strongly by the independent variables, these parameters were used in optimization of the process. The optimum temperature, feed mixture concentration, and percentage maltodextrin were 100°C, 30.8 °Brix, and 53.5% MD, respectively. This study revealed that by applying these optimal conditions, pomegranate juice powder with a 55% dry solids yield, 9.78 total color change, 0.35 g/mL bulk density, and 57.8% antioxidant capacity were produced. 相似文献
78.
79.
Burak Kantarci Luca Foschini Antonio Corradi Hussein T. Mouftah 《International Journal of Network Management》2015,25(2):75-94
Data centers play a crucial role in the delivery of cloud services by enabling on‐demand access to the shared resources such as software, platform and infrastructure. Virtual machine (VM) allocation is one of the challenging tasks in data center management since user requirements, typically expressed as service‐level agreements, have to be met with the minimum operational expenditure. Despite their huge processing and storage facilities, data centers are among the major contributors to greenhouse gas emissions of IT services. In this paper, we propose a holistic approach for a large‐scale cloud system where the cloud services are provisioned by several data centers interconnected over the backbone network. Leveraging the possibility to virtualize the backbone topology in order to bypass IP routers, which are major power consumers in the core network, we propose a mixed integer linear programming (MILP) formulation for VM placement that aims at minimizing both power consumption at the virtualized backbone network and resource usage inside data centers. Since the general holistic MILP formulation requires heavy and long‐running computations, we partition the problem into two sub‐problems, namely, intra and inter‐data center VM placement. In addition, for the inter‐data center VM placement, we also propose a heuristic to solve the virtualized backbone topology reconfiguration computation in reasonable time. We thoroughly assessed the performance of our proposed solution, comparing it with another notable MILP proposal in the literature; collected experimental results show the benefit of the proposed management scheme in terms of power consumption, resource utilization and fairness for medium size data centers. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
80.
Merve Erkmen Almaz Nur Burcu Ulusoy Aylin Akbay Oba Ümit Erdem Mustafa Doan 《Microscopy research and technique》2021,84(1):150-159
The aim of this study was to determine the temperature increase in the pulp chamber and possible thermal effects on molecular structure of primary teeth during the irradiation with Er,Cr:YSGG laser. Primary central incisors were divided into three groups (n = 20). Labial surfaces in each group were irradiated by Er,Cr:YSGG laser within different power and frequencies as following groups: I: 0.25 W, 20 Hz, II: 0.50 W, 20 Hz, III: 0.75 W, 20 Hz. A thermocouple was placed inside the pulp chamber so that the temperature increments were recorded during the enamel irradiation. Morphological changes of enamel surfaces were experimentally evaluated by SEM. Fourier‐transform infrared spectroscopy and RAMAN analyses were carried out to determine the differentiations in the molecular structure. The experimental results obtained were analyzed statistically by means of one‐way analysis of variance. Statistically significant differences were detected between groups (p < .05). Group III exhibited the highest values for the temperature parameters. Besides, the conical craters, cracks, and formation of ablation areas were observed for all the groups. Also, it was obtained that the hydroxyapatite lost the hydroxyl ions due to the thermal effect of the laser. Temperature rise throughout the Er,Cr:YSGG laser irradiation for prevention of primary enamel demineralization presented a positive correlation with the laser output power level. The formations of adverse morphological and spectral changes were detected on the surface of teeth after the laser application. On this basis, the Er,Cr:YSGG laser applications should be treated with much more caution considering enamel surface and pulpal tissues in primary teeth. 相似文献