排序方式: 共有21条查询结果,搜索用时 15 毫秒
1.
Medical data feature a number of characteristics that make their classification a complex task. Yet, the societal significance of the subject and the computational challenge it presents has caused the classification of medical datasets to be a popular research area. A new hybrid metaheuristic is presented for the classification task of medical datasets. The hybrid ant–bee colonies (HColonies) consists of two phases: an ant colony optimization (ACO) phase and an artificial bee colony (ABC) phase. The food sources of ABC are initialized into decision lists, constructed during the ACO phase using different subsets of the training data. The task of the ABC is to optimize the obtained decision lists. New variants of the ABC operators are proposed to suit the classification task. Results on a number of benchmark, real-world medical datasets show the usefulness of the proposed approach. Classification models obtained feature good predictive accuracy and relatively small model size. 相似文献
2.
3.
D. A. Yagodnikov A. V. Voronetskii V. I. Sarab’ev 《Combustion, Explosion, and Shock Waves》2016,52(3):300-306
This paper presents the experimental study of ignition and combustion of micro- and nanoparticles of aluminum diboride as part of pyrotechnic energy-saturated compositions in a gas generator with an air afterburner chamber and the thermodynamic calculations of combustion of pyrotechnic compositions based on aluminum diboride in air. The discharge of the combustion products from the afterburner chamber is recorded on video. It is shown that replacing micron aluminum diboride by powdered diboride with a mass-average diameter of particles equal to ≈270 nm in the pyrotechnic composition and increasing the pressure in the afterburner chamber cause the combustion efficiency in air to increase by 5–20%. 相似文献
4.
Ayad A. Al-Taweel Mohammed S. H. Ahmed Sarab S. Kadhum Asaad A. Hameed 《Journal of Stored Products Research》1990,26(4):233-236
One-day-old P1 males of Ephestia cautella, Baghdad strain, were treated with 0.15, 0.20 and 0.25 kGy of γ radiation and mated in groups (15 pairs) with untreated virgin females. Radiation effects were assayed by determining percentage of egg hatch, mating ability and F1 sex ratio. Our results showed the greater the initial dose, the greater the reduction in the percent egg hatch, and the greater the male-to-female ratio. Radiation effects on F1 males were greater than the effect on the P1 males. Furthermore, the results showed that the effects on F1 males were greater than the effects on F1 females. These results were confirmed cytologically by examination of the developing meiotic germ cells of F1 males which showed that the meiotic nuclei carried multiple translocations. Such chromosomal aberrations explain the sterility observed in the F1 male generation. 相似文献
5.
Within the field of e-Learning, a learning path represents a match between a learner profile and his preferences from one
side, and the learning content presentation and the pedagogical requirements from the other side. The Curriculum Sequencing
problem (CS) concerns the dynamic generation of a personal optimal learning path for a learner. This problem has gained an
increased research interest in the last decade, as it is not possible to have a single learning path that suits every learner
in the widely heterogeneous e-Learning environment. Since this problem is NP-hard, heuristics and meta-heuristics are usually
used to approximate its solutions, in particular Evolutionary Computation approaches (EC). In this paper, a review of recent
developments in the application of EC approaches to the CS problem is presented. A classification of these approaches is provided
with emphasis on the tools necessary for facilitating learning content reusability and automated sequencing. 相似文献
6.
7.
S.S. Madaeni M. Moahamadi Sarab Badieh V. Vatanpour N. Ghaemi 《Polymer Engineering and Science》2012,52(12):2664-2674
Introducing inorganic nanoparticles into the structure of polymeric membranes is an interesting approach for the enhancement of physical, chemical, and separation properties of the membranes. In this article, the performance of a two‐layer nanocomposite membrane for gas separation was studied. Three different methods for embedding titanium dioxide (TiO2) nanoparticle were employed for the membrane preparation. The techniques include blending TiO2 in the polydimethylsiloxane (PDMS) coating layer, blending TiO2 in the polyethersulfone (PES) support and dip coating of PES support with TiO2 accompanied by PDMS coating. The aim of the current research was finding the optimum technique for introducing TiO2 into the membrane to obtain superior performance for gas separation. The results indicated that PES support containing TiO2 nanoparticles possessed favorable effect on gas separation capability. The optimum performance was obtained by PDMS‐coated membranes prepared with 7 wt% TiO2‐embedded PES support. Carbon dioxide (CO2) permeance, CO2/nitrogen, and CO2/methane selectivity were obtained as 188.7 GPU, 8.6, and 3.4, respectively. POLYM. ENG. SCI., 2012. © 2012 Society of Plastics Engineers 相似文献
8.
Singh SP Otón CJ Srivastava P Ghosh S Prakash GV 《Journal of nanoscience and nanotechnology》2011,11(12):10733-10736
A systematic study of fabrication and effect of post-deposition processing on the optical and structural features of silicon-rich hydrogenated amorphous silicon nitride thin films deposited by Hg-sensitized Photo-Chemical Vapour Deposition technique is presented. Both deposition parameters and post-deposition thermal treatment resulted into substantial change in the refractive index associated with the densification of the film. Our studies reveal that the presence of hydrogen and its out-diffusion upon thermal treatment play a crucial role in the overall structural evolution, specially the stabilization of individual phases such as Si and Si3N4. We further report the room-temperature photoluminescence from as-deposited films, which is due to formation of silicon nanostructures in crystalline and amorphous forms. These studies are of great interest from the prospective of commercially viable Si-based technology. 相似文献
9.
S.S. Madaeni M. Mohammadi Sarab Badieh V. Vatanpour 《Polymer Engineering and Science》2013,53(9):1878-1885
In this study, polydimethylsiloxane (PDMS)‐coated polyethersulfone (PES) composite membrane was prepared for gas separation. “Film casting” and “dip‐coating” techniques were used for producing selective PDMS layer on the surface of the PES support. The effects of coating technique and conditions including coating solution concentration and curing temperature on permselectivity of CO2, CH4, and N2 were investigated. The prepared PES support did not provide any selectivity to the gases. When the concentration of PDMS coating solution was increased, initially permeability of CO2 was rapidly dropped and then gradually reached to an almost constant value. The optimum concentration of coating solution was 5 wt%. Curing temperature showed no pronounced effect on the CO2 permeability and selectivity. In “film casting” method, double coating showed superior permeability and selectivity. However, triple “dip‐coating” was promising. The selectivity of composite membrane prepared by “dip‐coating” was higher than “film casting” method. CO2/N2 and CO2/CH4 selectivity of five sequential dip‐coated composite membranes was 45.5 and 9.3, respectively. POLYM. ENG. SCI., 2013. © 2013 Society of Plastics Engineers 相似文献
10.
Sarab AlMuhaideb Reem BinGhannam Nourah Alhelal Shatha Alduheshi Fatimah Alkhamees Raghad Alsuhaibani 《计算机、材料和连续体(英文)》2021,66(2):1329-1346
Medical data classification (MDC) refers to the application of classification methods on medical datasets. This work focuses on applying a classification task to medical datasets related to specific diseases in order to predict the associated diagnosis or prognosis. To gain experts’ trust, the prediction and the reasoning behind it are equally important. Accordingly, we confine our research to learn rule-based models because they are transparent and comprehensible. One approach to MDC involves the use of metaheuristic (MH) algorithms. Here we report on the development and testing of a novel MH algorithm: IWD-Miner. This algorithm can be viewed as a fusion of Intelligent Water Drops (IWDs) and AntMiner+. It was subjected to a four-stage sensitivity analysis to optimize its performance. For this purpose, 21 publicly available medical datasets were used from the Machine Learning Repository at the University of California Irvine. Interestingly, there were only limited differences in performance between IWD-Miner variants which is suggestive of its robustness. Finally, using the same 21 datasets, we compared the performance of the optimized IWD-Miner against two extant algorithms, AntMiner+ and J48. The experiments showed that both rival algorithms are considered comparable in the effectiveness to IWD-Miner, as confirmed by the Wilcoxon nonparametric statistical test. Results suggest that IWD-Miner is more efficient than AntMiner+ as measured by the average number of fitness evaluations to a solution (1,386,621.30 vs. 2,827,283.88 fitness evaluations, respectively). J48 exhibited higher accuracy on average than IWD-Miner (79.58 vs. 73.65, respectively) but produced larger models (32.82 leaves vs. 8.38 terms, respectively). 相似文献