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排序方式: 共有3003条查询结果,搜索用时 15 毫秒
11.
12.
Cássia A. Glasser Marta M. D. C. Vila Júlio C. Pereira Marco V. Chaud José M. Oliveira Júnior Matthieu Tubino 《Drug development and industrial pharmacy》2016,42(12):1990-2000
The aqueous-core enclosed in lipid nanoballoons integrating multiple emulsions of the type water-in-oil-in-water mimic, at least in theory, the environment within viable cells, thus being suitable for housing hydrophilic protein entities such as bioactive proteins, peptides and bacteriophage particles. This study reports a complete physicochemical characterization of optimized biomimetic aqueous-core lipid nanoballoons housing hydrophilic (BSA) protein entities, evolved from a statistical 23×31 factorial design study (three variables at two levels and one variable at three levels) that was the subject of the first paper of a series of three, aiming at complete stabilization of the three-dimensional structure of protein entities attempted via housing the said molecular entities within biomimetic aqueous-core lipid nanoballoons integrating a multiple (W/O/W) emulsion. The statistical factorial design followed led to the production of an optimum W/O/W multiple emulsion possessing quite homogeneous particles with an average hydrodynamic size of (186.2?±?2.6) nm and average Zeta potential of (?36.5?±?0.9) mV, and exhibiting a polydispersity index of 0.206?±?0.014. Additionally, the results obtained for the diffusion coefficient of the lipid nanoballoons integrating the optimized W/O/W multiple emulsion were comparable and of the same order of magnitude (10?12 m2 s?1) as those published by other authors since, typically, diffusion coefficients for molecules range from 10?10 to 10?7 m2 s?1, but diffusion coefficients for nanoparticles are typically of the order of magnitude of 10?12 m2 s?1. 相似文献
13.
Yakup Kara Melek Acar Boyacioglu Ömer Kaan Baykan 《Expert systems with applications》2011,38(5):5311-5319
Prediction of stock price index movement is regarded as a challenging task of financial time series prediction. An accurate prediction of stock price movement may yield profits for investors. Due to the complexity of stock market data, development of efficient models for predicting is very difficult. This study attempted to develop two efficient models and compared their performances in predicting the direction of movement in the daily Istanbul Stock Exchange (ISE) National 100 Index. The models are based on two classification techniques, artificial neural networks (ANN) and support vector machines (SVM). Ten technical indicators were selected as inputs of the proposed models. Two comprehensive parameter setting experiments for both models were performed to improve their prediction performances. Experimental results showed that average performance of ANN model (75.74%) was found significantly better than that of SVM model (71.52%). 相似文献
14.
Selin Soner Kara 《Expert systems with applications》2011,38(3):2133-2139
This paper proposes an integrated methodology and its solution for supplier selection problem. A two-stage stochastic programming model and fuzzy TOPSIS methods are consolidated in this methodology. After pre-research phase, in the second part of the methodology, fuzzy TOPSIS is used for ranking potential suppliers considering qualitative data under fuzzy environment. In the third part of the methodology a group of ranked potential suppliers are included in a two-stage stochastic programming model for evaluation. In the two-stage stochastic programming model demand is assumed as uncertain and different scenarios are generated for this parameter. With this methodology, supplier evaluation procedure can be done in unknown environment. Our methodology is interested with a problem in multi-product, multi-period and multi-sourcing environment. 相似文献
15.
Marta Alberti Joaquim Ciurana Ciro A. Rodríguez Tugrul Özel 《Journal of Intelligent Manufacturing》2011,22(2):263-277
Economic globalization, together with heightened market competition and increasingly short product life cycles are motivating
companies to use advanced manufacturing technologies. Use of high speed machining is increasingly widespread; however, as
the technology is relatively new, it lacks a deep-rooted knowledge base which would facilitate implementation. One of the
most frequent problems facing companies wishing to adopt this technology is selecting the most appropriate machine tool for
the product in question and own enterprise characteristics. This paper presents a decision support system for high speed milling
machine tool selection based on machine characteristics and performance tests. Profile machining tests are designed and conducted
in participating machining centers. The decision support system is based on product dimension accuracy, process parameters
such as feed rate and interpolation scheme used by CNC and machine characteristics such as machine accuracy and cost. Experimental
data for process error and cycle operation time are obtained from profile machining tests with different geometrical feature
zones that are often used in manufacturing of discrete parts or die/moulds. All those input parameters have direct impact
on productivity and manufacturing cost. Artificial neural network models are utilized for decision support system with reasonable
prediction capability. 相似文献
16.
José Luis Crespo Marta Zorrilla Pilar Bernardos Eduardo Mora 《The Visual computer》2009,25(4):309-323
The objective of this paper is to present an overall approach to forecasting the future position of the moving objects of
an image sequence after processing the images previous to it. The proposed method makes use of classical techniques such as
optical flow to extract objects’ trajectories and velocities, and autoregressive algorithms to build the predictive model.
Our method can be used in a variety of applications, where videos with stationary cameras are used, moving objects are not
deformed and change their position with time. One of these applications is traffic control, which is used in this paper as
a case study with different meteorological conditions to compare with.
相似文献
Marta Zorrilla (Corresponding author)Email: |
17.
Comparison of different classifier algorithms for diagnosing macular and optic nerve diseases 总被引:1,自引:1,他引:0
Abstract: The aim of this research was to compare classifier algorithms including the C4.5 decision tree classifier, the least squares support vector machine (LS-SVM) and the artificial immune recognition system (AIRS) for diagnosing macular and optic nerve diseases from pattern electroretinography signals. The pattern electroretinography signals were obtained by electrophysiological testing devices from 106 subjects who were optic nerve and macular disease subjects. In order to show the test performance of the classifier algorithms, the classification accuracy, receiver operating characteristic curves, sensitivity and specificity values, confusion matrix and 10-fold cross-validation have been used. The classification results obtained are 85.9%, 100% and 81.82% for the C4.5 decision tree classifier, the LS-SVM classifier and the AIRS classifier respectively using 10-fold cross-validation. It is shown that the LS-SVM classifier is a robust and effective classifier system for the determination of macular and optic nerve diseases. 相似文献
18.
In this paper we introduce a method to compute non-dominated bicriteria shortest pairs, each including two disjoint simple paths. The method is based on an algorithm for ranking pairs of disjoint simple paths by non-decreasing order of cost, that is an adaptation of a path ranking algorithm applied to a network obtained from the original one after a suitable modification of the topology. Each path in this new network corresponds to a pair of paths in the former one. Computational results are presented and analysed for randomly generated networks. 相似文献
19.
Hub location problems deal with finding the location of hub facilities and with the allocation of demand nodes to these located hub facilities. In this paper, we study the single allocation hub covering problem over incomplete hub networks and propose an integer programming formulation to this end. The aim of our model is to find the location of hubs, the hub links to be established between the located hubs, and the allocation of non-hub nodes to the located hub nodes such that the travel time between any origin–destination pair is within a given time bound. We present an efficient heuristic based on tabu search and test the performance of our heuristic on the CAB data set and on the Turkish network. 相似文献
20.
Reinforced concrete shear walls are used in tall buildings for efficiently resisting lateral loads. Due to the low tensile strength of concrete, reinforced concrete shear walls tend to behave in a nonlinear manner with a significant reduction in stiffness, even under service loads. To accurately assess the lateral deflection of shear walls, the prediction of flexural and shear stiffness of these members after cracking becomes important. In the present study, an iterative analytical procedure which considers the cracking in the reinforced concrete shear walls has been presented. The effect of concrete cracking on the stiffness and deflection of shear walls have also been investigated by the developed computer program based on the iterative procedure. In the program, the variation of the flexural stiffness of a cracked member has been evaluated by ACI and probability-based effective stiffness model. In the analysis, shear deformation which can be large and significant after development of cracks is also taken into account and the variation of shear stiffness in the cracked regions of members has been considered by using effective shear stiffness model available in the literature. Verification of the proposed procedure has been confirmed from series of reinforced concrete shear wall tests available in the literature. Comparison between the analytical and experimental results shows that the proposed analytical procedure can provide an accurate and efficient prediction of both the deflection and flexural stiffness reduction of shear walls with different height to width ratio and vertical load. The results of the analytical procedure also indicate that the percentage of shear deflection in the total deflection increases with decreasing height to width ratio of the shear wall. 相似文献