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51.
Ladislav J. Kohout Isabel Stabile Hasan Kalantar F. San-Andres John Anderson 《Reliable Computing》1995,1(2):109-140
The paper continues a series of papers and a monograph [33], where we have described the conceptual structures as well as the basic architecture of a knowledge-based systemCunaid. 相似文献
52.
Neural computing models for prediction of permeability coefficient of coarse-grained soils 总被引:1,自引:0,他引:1
I??k Yilmaz Marian Marschalko Martin Bednarik O?uz Kaynar Lucie Fojtova 《Neural computing & applications》2012,21(5):957-968
Correlations are very significant from the earliest days; in some cases, it is essential as it is difficult to measure the amount directly, and in other cases it is desirable to ascertain the results with other tests through correlations. Soft computing techniques are now being used as alternate statistical tool, and new techniques such as artificial neural networks, fuzzy inference systems, genetic algorithms, and their hybrids were employed for developing the predictive models to estimate the needed parameters, in the recent years. Determination of permeability coefficient (k) of soils is very important for the definition of hydraulic conductivity and is difficult, expensive, time-consuming, and involves destructive tests. In this paper, use of some soft computing techniques such as ANNs (MLP, RBF, etc.) and ANFIS (adaptive neuro-fuzzy inference system) for prediction of permeability of coarse-grained soils was described and compared. As a result of this paper, it was obtained that the all constructed soft computing models exhibited high performance for predicting k. In order to predict the permeability coefficient, ANN models having three inputs, one output were applied successfully and exhibited reliable predictions. However, all four different algorithms of ANN have almost the same prediction capability, and accuracy of MLP was relatively higher than RBF models. The ANFIS model for prediction of permeability coefficient revealed the most reliable prediction when compared with the ANN models, and the use of soft computing techniques will provide new approaches and methodologies in prediction of some parameters in soil mechanics. 相似文献
53.
Kamil Musilek Dr. Ondrej Holas Jan Misik Miroslav Pohanka Dr. Ladislav Novotny Vlastimil Dohnal Dr. Veronika Opletalova Kamil Kuca Dr. 《ChemMedChem》2010,5(2):247-254
Acetylcholinesterase (AChE) reactivators are crucial antidotes to organophosphate intoxication. A new series of 26 monooxime‐monocarbamoyl xylene‐linked bispyridinium compounds was prepared and tested in vitro, along with known reactivators (pralidoxime, HI‐6, obidoxime, trimedoxime, methoxime, K107, K108 and K203), on a model of tabun‐ and paraoxon‐, methylparaoxon‐ and DFP‐inhibited human erythrocyte AChE. Although their ability to reactivate tabun‐inhibited AChE did not exceed that of the previously known compounds, some newly prepared compounds showed promising reactivation of pesticide‐inhibited AChE. The acute toxicity of the novel compounds was also determined. Docking studies using tabun‐inhibited AChE were performed for three compounds of interest. The structure–activity relationship (SAR) study confirmed the apparent influence of the xylene linkage and carbamoyl moiety on the reactivation ability and toxicity of the agents. 相似文献
54.
Stabilization of -alumina phase by silica was studied in nanocomposite (diphasic) alumina-silica gels by XRD and BET surface areas measurements. Five wt.% of silica (22 nm particles) increased the crystallization temperature of to -alumina by about 100°C from boehmite (10 nm particles) derived alumina. Stabilization of -alumina was caused by the formation of intimate contact (Al-O-Si) between components by diffusion of silica into the defect alumina structure.Also with the Department of Agronomy. 相似文献
55.
Mullite formation process has been studied in stoichiometric mullite (3Al2O3·2SiO2) diphasic gel containing large boehmite (1 m) and small silica (10 nm) particles. It has been found that initial mullitization did not take place inside the silica phase (cristobalite), but took place in the defect -alumina phase. -alumina was stabilized by silica when the temperature was below 1350°C. At temperatures above 1350°C, mullite crystallized directly. It was suggested that silica diffused into the pores (<1.8 nm) of -alumina and prevented the collapse of -alumina pore structure. On the other hand, when silica was not present, the pore structure of -alumina collapsed and -alumina crystallized at 1100°C. Porous mullite ceramics were obtained by using special diphasic gels containing large boehmite and small silica particles. 相似文献
56.
The first in situ electron paramagnetic resonance (EPR) spectroelectrochemical study of C60 fullerene peapods (C60@SWCNT) as well as that of single-walled carbon nanotubes (SWCNTs) in different electrolyte solutions describes the formation of spin states by charge transfer reactions. Electrochemical reduction of peapods at high negative potentials causes the production of spins at the SWCNT site, while the intratubular fullerene is unchanged.Slightly anisotropic EPR signals were detected during electrochemical reduction of single-walled carbon nanotubes and fullerene peapods in the potential region from −1.75 to −2.15 V vs. decamethylferrocene/decamethylferrocinium couple. They are centered at g = 2.0038 and exhibit a hyperfine structure indicating the presence of functional groups containing N, O, H atoms in neighborhood. They differ from the EPR signals of chemically (potassium) doped SWCNT and C60@SWCNT. As the EPR signal is influenced by the electrolyte counter ions a reaction with electrolysis products of tetraalkylammonium cations is taken into consideration. No EPR lines of fullerene anions were found in electrochemically treated peapods, but these anions are detectable, if a free C60 in solution is cathodically reduced on a SWCNT electrode. 相似文献
57.
Puncture is a common operation in surgery, which involves all kinds of tissue materials with different geometry and mechanical properties. As a new cross-disciplinary research area, Virtual Surgery (VS) makes simulation of soft tissue in puncture operation possible in virtual environment. In this paper, we introduce a VS-based puncture system composed by three-layer soft tissue, simulated with spherical harmonic function (SHF), which is covered with a force mesh, constructed by mass spring model (MSM). The two models are combined together with a parameter of SHF named surface radius, which provides MSM with real-time deformation data needed in force calculation. Meanwhile, force calculation, divided into the surface spring force and the puncture damping force, makes the force presentation better accord to the corresponding tissue characteristics. Moreover, a deformation resumption algorithm is leveraged to simulate the resumption phenomenon of the broken tissue surface. In evaluation experiment, several residents are invited to grades our model along with other four mainstream soft tissue models in terms of 7 different indicators. After the evaluation, the scores are analyzed by a comprehensive weighted grading method. Experiment results show that the proposed model has better performance during puncture operation than other models, and can well simulate surface resumption phenomenon when tissue surface is broken. 相似文献
58.
Defects in individual semiconducting single wall carbon nanotubes: Raman spectroscopic and in situ Raman spectroelectrochemical study 总被引:1,自引:0,他引:1
Kalbac M Hsieh YP Farhat H Kavan L Hofmann M Kong J Dresselhaus MS 《Nano letters》2010,10(11):4619-4626
Raman spectroscopy and in situ Raman spectroelectrochemistry have been used to study the influence of defects on the Raman spectra of semiconducting individual single-walled carbon nanotubes (SWCNTs). The defects were created intentionally on part of an originally defect-free individual semiconducting nanotube, which allowed us to analyze how defects influence this particular nanotube. The formation of defects was followed by Raman spectroscopy that showed D band intensity coming from the defective part and no D band intensity coming from the original part of the same nanotube. It is shown that the presence of defects also reduces the intensity of the symmetry-allowed Raman features. Furthermore, the changes to the Raman resonance window upon the introduction of defects are analyzed. It is demonstrated that defects lead to both a broadening of the Raman resonance profile and a decrease in the maximum intensity of the resonance profile. The in situ Raman spectroelectrochemical data show a doping dependence of the Raman features taken from the defective part of the tested SWCNT. 相似文献
59.
Capillary absorption kinetics of concrete–ethylene glycol system was studied with respect to concrete matrix porosity and liquid viscosity. Porosity of specimens was altered by air-entraining agents and superplasticizers. Liquid which doesn’t react with cement gel was chosen for the experiment in order to study the reasons for deviation from Lucas–Washburn equation observed in concrete–water system. Viscosity of ethylene glycol changes from ~23 to 2 mPa s in the temperature range from 20 to 100 °C. The values of the capillary coefficient were determined at 20, 60 and 100 °C using Neutron Radiography and were found to be in the range from ~1.5 to 4.9 mm h?1/2. The results show that the Lucas–Washburn equation in concrete–ethylene glycol system is valid only for ~25 h, which indicates that swelling and rehydration of cement gel are not the main reasons for deviation observed in concrete–water system. 相似文献
60.
Young Richard A.; Valach Ladislav; Ball Jessica; Paseluikho Michele A.; Wong Yuk Shuen; DeVries Raymond J.; McLean Holly; Turkel Hayley 《Canadian Metallurgical Quarterly》2001,48(2):190
This study conceptualizes and investigates career-relevant parent–child conversations and other actions over time as a family project. Dyads composed of a parent and an adolescent from 20 families participated in a videotaped career-related conversation to determine a family career-development project that was subsequently monitored for a 6-month period and followed up with a 2nd videotaped conversation. On the basis of a systematic qualitative analysis, several dimensions were identified as facilitating the family career-development project, including joint goals, communication, goals-steps congruence, and individuation. These family career-development projects were organized as part of broader relationship, identity, parenting, and cultural projects that also played a decisive role in the success of the family career-development projects themselves. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献