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A new class of functions called L-fuzzy weakly semi-preopen (semi-preclosed) functions in L-fuzzy topological spaces is introduced in this paper. Some characterizations of this class and its properties and the relationship with other classes of functions between L-fuzzy topological spaces are also obtained.  相似文献   
3.
The authors aimed to examine a multivariate statistical analysis approach for monitoring the hydrocarbon potentiality of source rocks in the North Western Desert to recognize the potentiality of source rocks and subsequently investigate the maturation level of the proven potential source formations for oil preservation. To achieve this aim, they applied multivariate statistics analysis (principle component analysis [PCA], cluster analysis, and correlation coefficient) and Rock-Eval pyrolysis analyses. The results showed that both PCA and cluster analyses have showed two types of source rocks. The first is classified as poor to fair source rock and immature to marginally mature source rock, the second is considered as fair to good source rock and mature to post mature source rock. PCA extracted two independent factors, which explained 81.87% of the total variance. The first type of source rock was responsible for 50% of the total variance and was best represented by variables TOC, S2, OI, and Ro, and the second one was responsible for 31.65% of the total variance and was represented by the HI variable. Pearson correlation coefficient showed a significant positive correlation between TOC and S2 or Ro. A positive correlation between S2 and HI or OI and also between OI and Ro was observed, while no significant correlation was noticed between HI and Ro.  相似文献   
4.
A novel hydrogel based on the orange peel (OP) and N-vinyl-2-pyrrolidone was prepared by free-radical polymerization using gamma irradiation. The effect of radiation dose and hydrogel composition on gel content was studied. The formed hydrogel was characterized by FT-IR, TGA, and SEM. The swelling behavior was determined as a function of swelling time, pH, and OP content. The hydrogel swelling was found to be pH dependent, and the diffusion mechanism of water into the hydrogel was found Fickian. The developed hydrogel was used for the removal of Congo red (CR) and methyl orange (MO) dyes from wastewater. The effects of various operating parameters, such as initial pH, contact time, initial dye concentration, and temperature on the removal of dyes, have been investigated. The Langmuir and the Freundlich adsorption models were applied to study the adsorption isotherm. The pseudo-first-order model was proved compatible for CR adsorption and the pseudo-second-order model well described the adsorption of MO. The adsorption of dyes increased with increasing temperature indicating that the endothermic nature of the adsorption process and the thermodynamic parameters was evaluated. Second, the adsorption cycle of dyes was also examined and discussed utilizing the loaded hydrogel with the other dye and cobalt metal ions.  相似文献   
5.
The refining of lubricating oils from waste lubricating oil was examined utilizing a novel blend of solvent extraction and activated alumina adsorbent. The activity of these solvent extraction blends {toluene, butanol and methanol (A)}, {toluene, butanol and ethanol (B)} and {toluene, butanol and isopropanol (C)} was evaluated experimentally, oil to solvent proportions from 1:1 to 1:3 were analyzed for mixture blend (C). The results confirm solvent mixture (A) gave good efficiency with the highest percent sludge removal. The maximum percent of sludge removal improves with the increase of solvent to oil ratios. The physical properties of the recycle oil were measured. The results show the change in the properties of recycling oil and have good efficiency.  相似文献   
6.
In this paper, the quality metrics suite for object oriented (OO) design is partially used as an initial concept to develop metrics for statically measuring quality of KADS-domain knowledge bases. KADS-domain knowledge bases have common characteristics with OO, and other distinct features that limit the usage of some OO quality metrics. Therefore, new sets of domain knowledge quality metrics are proposed. The proposed matrices are enriched with an automatic tool used to measure quality of real world expert systems. In order to assess the effectiveness of these proposed quality metrics, these metrics were applied on a sample of real world agriculture application domains developed by CLAES (The Central Laboratory of Agriculture Expert System). Finally, complete analysis of the results obtained due to applying these metrics is presented.  相似文献   
7.
Testicular parenchyma is split into lobules, each lobule contains convoluted seminiferous tubules surrounded by myoid cells and the interstitial tissue contains groups of Leydig cells. The seminiferous tubules are lined by two groups of cells the first one is the spermatogenic cells and the second one is Sertoli cells.  相似文献   
8.
The effect of the methods for handling missing values on the performance of Phase I multivariate control charts has not been investigated. In this paper, we discuss the effect of four imputation methods: mean substitution, regression, stochastic regression and the expectation maximization algorithm. Estimates of mean vector and variance covariance matrix from the treated data set are used to estimate the unknown parameters in the Hotelling's T2 chart statistic. Based on a Monte Carlo simulation study, the performance of each of the four methods is investigated in terms of its ability to obtain the nominal in‐control and out‐of‐control overall probability of a signal. We consider three sample sizes, five levels of the percentage of missing values and three types of variable numbers. Our simulation results show that the stochastic regression method has the best overall performance among all the competing methods. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
9.
Texture analysis (TA) combined with dedicated gradient echo magnetic resonance imaging (MRI) at high field provides specific parametric maps of connective tissue and allows statistical analysis of the resulting texture. The present study clearly demonstrates that MRI‐TA of bovine meat can discriminate between muscle types Gluteo biceps and Pectoralis profundus, and between genotype origins corresponding to the mutation on the myostatin gene: normal +/+, heterozygous mh/+ or homozygous double‐muscled mh/mh Belgian White Blue bulls. Values of interclass separations reflect the significantly different collagen and fat contents in these genotypes. To our knowledge, no previous study has demonstrated such a correlation between MRI texture and genetics‐related modifications. Copyright © 2004 Society of Chemical Industry  相似文献   
10.
Abstract

Introduction: Periodontal disease broadly defines group of conditions in which the supportive structure of the tooth (periodontium) is destroyed. Recent studies suggested that the anti-diabetic drug metformin hydrochloride (MF) has an osteogenic effect and is beneficial for the management of periodontitis.

Objective: Development of strong mucoadhesive multiple layer film loading small dose of MF for intra-pocket application.

Methodology: Multiple layer film was developed by double casting followed by compression method. Either 6% carboxy methyl cellulose sodium (CMC) or sodium alginate (ALG) constituted the inner drug (0.6%) loaded layer. Thiolated sodium alginate (TSA; 2 or 4%) constituted the outer drug free layers to enhance mucoadhesion and achieve controlled drug release. Optimized formulation was assessed clinically on 20 subjects.

Results: Films were uniform, thin and hard enough for easy insertion into periodontal pockets. Based on water uptake and in vitro drug release, CMC based film with 4% TSA as an outer layer was the optimized formulation with enhanced mucoadhesion and controlled drug release (83.73% over 12?h). SEM showed the effective fabrication of the triple layer film in which connective lines between the layers could be observed. FTIR examination suggests possibility of hydrogen bonding between the –NH groups of metformin and –OH groups of CMC. DSC revealed the presence of MF mainly in the amorphous form. Clinical results indicated improvement of all clinical parameters six months post treatment.

Conclusion: The results suggested that local application of the mucoadhesive multiple layer films loaded with metformin hydrochloride was able to manage moderate chronic periodontitis.  相似文献   
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