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1.
The microstructural aspects of compressive inelastic deformation in balsa wood are investigated with emphasis on the failure mode transition and its effects on energy dissipation characteristics. The architectural features as well as the composite character of cell wall ultrastructure are discussed in a framework to understand the complex interrelationship between microstructure and macroscopic behavior in this extremely lightweight cellular biocomposite. Based on this discussion and experimental results, it is concluded that the biomimetic approach may prove to be a viable strategy in designing composite structures with high specific energy absorption capacity. 相似文献
2.
Three interesterified vegetable oils (IVOs) prepared from palm, cottonseed, and olive oil, respectively, have been studied for application to Frankfurters. Beef fat (10%) was replaced by one of the IVOs at 20, 60 or 100%. Fatty acid composition of the lipid fraction in the Frankfurters and saturated/unsaturated ratios were established for all batches. We found that total or partial replacement of beef fat by IVOs did not lead to significant changes in appearance, colour, texture, flavour or sensory score. We conclude that IVOs may be successfully applied as beef fat substitutes in Frankfurters. 相似文献
3.
The in vitro activities of the N,N-dimethylglycyl-amino derivative of minocycline (DMG-MINO) and 6-dimethyl-6-dexoxytetracycline (DMG-DMDOT), members of a new generation of tetracyclines, were evaluated by an agar dilution method and were compared with those of tetracycline and minocycline against 224 tetracycline-resistant and 73 tetracycline-susceptible recent clinical isolates of gram-positive cocci, including multiple-antibiotic-resistant methicillin-resistant Staphylococcus aureus and penicillin-resistant Streptococcus pneumoniae. The MICs of DMG-MINO and DMG-DMDOT were up to 500- to 2,000-fold lower than those of tetracycline against methicillin-resistant S. aureus and Streptococcus pneumoniae (MIC for 50% of strains tested [MIC50], < 0.06 microgram/ml). Against Streptococcus groups A, B, C, and G and Enterococcus faecalis, the MIC50 was 0.5 microgram/ml. MIC50s were greater only for coagulase-negative staphylococci (2 micrograms/ml). These data indicate that DMG-MINO and DMG-DMDOT are very potent drugs, and further in vitro and in vivo studies are warranted. 相似文献
4.
5.
Acar Seda Bekin Tasdelen Mehmet Atilla Karaagac Bagdagul 《Iranian Polymer Journal》2021,30(7):697-705
Iranian Polymer Journal - The addition of methacrylate-functional polyhedral oligomeric silsesquioxane (MA-POSS) nanoparticles to styrene-butadiene rubber (SBR) composites was evaluated in terms of... 相似文献
6.
Amr Almaddah Sadi Vural Yasushi Mae Kenichi Ohara Tatsuo Arai 《Machine Vision and Applications》2014,25(4):845-857
As part of the face recognition task in a robust security system, we propose a novel approach for the illumination recovery of faces with cast shadows and specularities. Given a single 2D face image, we relight the face object by extracting the nine spherical harmonic bases and the face spherical illumination coefficients by using the face spherical spaces properties. First, an illumination training database is generated by computing the properties of the spherical spaces out of face albedo and normal values estimated from 2D training images. The training database is then discriminately divided into two directions in terms of the illumination quality and light direction of each image. Based on the generated multi-level illumination discriminative training space, we analyze the target face pixels and compare them with the appropriate training subspace using pre-generated tiles. When designing the framework, practical real-time processing speed and small image size were considered. In contrast to other approaches, our technique requires neither 3D face models nor restricted illumination conditions for the training process. Furthermore, the proposed approach uses one single face image to estimate the face albedo and face spherical spaces. In this work, we also provide the results of a series of experiments performed on publicly available databases to show the significant improvements in the face recognition rates. 相似文献
7.
Unsupervised Multiway Data Analysis: A Literature Survey 总被引:1,自引:0,他引:1
Two-way arrays or matrices are often not enough to represent all the information in the data and standard two-way analysis techniques commonly applied on matrices may fail to find the underlying structures in multi-modal datasets. Multiway data analysis has recently become popular as an exploratory analysis tool in discovering the structures in higher-order datasets, where data have more than two modes. We provide a review of significant contributions in the literature on multiway models, algorithms as well as their applications in diverse disciplines including chemometrics, neuroscience, social network analysis, text mining and computer vision. 相似文献
8.
Sunil Kumar Richard J. Pippy Erdem Acar Nam H. Kim Raphael T. Haftka 《Structural and Multidisciplinary Optimization》2009,38(6):613-626
Probabilistic structural design deals with uncertainties in response (e.g. stresses) and capacity (e.g. failure stresses).
The calculation of the structural response is typically expensive (e.g., finite element simulations), while the capacity is
usually available from tests. Furthermore, the random variables that influence response and capacity are often disjoint. In
previous work we have shown that this disjoint property can be used to reduce the cost of obtaining the probability of failure
via Monte Carlo simulations. In this paper we propose to use this property for an approximate probabilistic optimization based
on exact capacity and approximate response distributions (ECARD). In Approximate Probabilistic Optimization Using ECARD, the
change in response distribution is approximated as the structure is re-designed while the capacity distribution is kept exact,
thus significantly reducing the number of expensive response simulations. ECARD may be viewed as an extension of SORA (Sequential
Optimization and Reliability Assessment), which proceeds with deterministic optimization iterations. In contrast, ECARD has
probabilistic optimization iterations, but in each iteration, the response distribution is approximated so as not to require
additional response calculations. The use of inexpensive probabilistic optimization allows easy incorporation of system reliability
constraints and optimal allocation of risk between failure modes. The method is demonstrated using a beam problem and a ten-bar
truss problem. The former allocates risk between two different failure modes, while the latter allocates risk between members.
It is shown that ECARD provides most of the improvement from risk re-allocation that can be obtained from full probabilistic
optimization. 相似文献
9.
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
10.
Acar Esra Hopfgartner Frank Albayrak Sahin 《Multimedia Tools and Applications》2017,76(9):11809-11837
Multimedia Tools and Applications - In today’s society where audio-visual content such as professionally edited and user-generated videos is ubiquitous, automatic analysis of this content is... 相似文献