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21.
Simulation of aerated lagoon using artificial neural networks and multivariate regression techniques
Karla Patricia Oliveira-Esquerre Aline C. da Costa Roy Edward Bruns Milton Mori 《Applied biochemistry and biotechnology》2003,106(1-3):437-449
The aim of this study was to develop an empirical model that provides accurate predictions of the biochemical oxygen demand
of the output stream from the aerated lagoon at International Paper of Brazil, one of the major pulp and paper plants in Brazil.
Predictive models were calculated from functional link neural networks (FLNNs), multiple linear regression, principal components
regression, and partial least-squares regression (PLSR). Improvement in FLNN modeling capability was observed when the data
were preprocessed using the PLSR technique. PLSR also proved to be a powerful linear regression technique for this problem,
which presents operational data limitations. 相似文献
22.
A systematic quantum chemical characterization of intrinsic structure, energies and spectral properties of all the studied cross-link adducts formed by the novel trans platinum with thiazole ligand has been carried out at B3LYP/6-31G^* level of theory with the Lanl2dz pseudo potential basis set for the Pt atom. Special attention has been paid to the relative stability of these complexes and the factors that probably alter the order of the relative stability. The important influence of hydrogen bond on the structures, the energies and the spectral property was revealed. Other factors that contribute to relative stability including solvation effect, entropy and electronic delocalization energy were taken into account. The stability energy of the whole complex, and the interaction energy between two purine bases and the [Pt-(NH3)thiazole]^2+ group were adopted to study the interplay among subsystems and their contribution to relative stability of all the studied cross-link model. Finally, basic spectral properties of these complexes including H(8) chemical shifts of all the studied complexes and the VCD (vibrational circular dichroism) spectra of two pairs of GG chelate enantiomers, were provided in order to define the structure of the most possible duplex bearing novel trans platinum drug lesions. 相似文献
23.
24.
E. J. Janse van Rensburg E. Orlandini D. W. Sumners M. C. Tesi S. G. Whittington 《Journal of statistical physics》1996,85(1-2):103-130
We consider a discrete ribbon model for double-stranded polymers where the ribbon is constrained to lie in a three-dimensional lattice. The ribbon can be open or closed, and closed ribbons can be orientable or nonorientable. We prove some results about the asymptotic behavior of the numbers of ribbons withn plaquettes, and a theorem about the frequency of occurrence of certain patterns in these ribbons. We use this to derive results about the frequency of knots in closed ribbons, the linking of the boundary curves of orientable closed ribbons, and the twist and writhe of ribbons. We show that the centerline and boundary of a closed ribbon are both almost surely knotted in the infinite-n limit. For an orientable ribbon, the expectation of the absolute value of the linking number of the two boundary curves increases at least as fast as n, and similar results hold for the twist and writhe. 相似文献
25.
随着信息化大数据时代的到来,既给信息科技从业者带来新的机遇和挑战的同时,也给大众百姓的生活带来巨大的品质提升,数字生活社区将引导一场前所未有的技术革命,对影响人们衣、食、住、行、医等方方面面,也使得人们对科技生活的依赖性更加增强,更加的理所当然. 相似文献
26.
The link quality was vulnerable to the complexity environment in wireless sensor network.Obtaining link quality information in advance could reduce energy consumption of nodes.After analyzing the existing link quality prediction methods,AdaBoost-based link quality prediction mechanism was put forward.Link quality samples in deferent scenarios were collected.Density-based unsupervised clustering algorithm was employed to classify training samples into deferent link quality levels.The AdaBoost with SVM-based component classifiers was adopted to build link quality prediction mechanism.Experimental results show that the proposed mechanism has better prediction precision. 相似文献
27.
This paper presents a link adaptation algorithm dedicated for 100 Gbps wireless transmission. Interleaved Reed-Solomon codes are selected as forward error correction (FEC) algorithms. The redundancy of the codes is selected according to the channel bit error rate (BER). The uncomplicated FEC scheme allows implementing a complete data link layer processor in an FPGA (field programmable gate array). In our case, we use the Virtex7 FPGA to validate the functionality of our implementation. The proposed FPGA-processor achieves 169 Gbps throughput. Moreover, the implementation is synthesized into 40 nm CMOS technology and the described link adaptation algorithm allows reducing consumed energy per bit to values below 1 pJ/bit at BER <1e−4. With higher BER, the energy increases up to ∼13 pJ/bit. 相似文献
28.
29.
There is growing recognition that blockchain technology has significant potential to alter how organizations and people work and communicate. However, theoretical guidance concerning how organizations leverage blockchain technology to enhance value creation for users is still limited. Grounded in the socio-technical perspective and leveraging the rich data obtained from case analyses of blockchain-enabled online communities, this paper develops a theoretical model to identify the core value drivers that blockchain enables for online communities. The core value drivers include: a reputation-value system, data ownership mechanisms, and verification & tracking mechanisms. Our findings suggest that these three value drivers enhance value creation of online communities by motivating participation and protecting contributions. 相似文献
30.
Noelia Santamaría-Cárdaba 《School science and mathematics》2020,120(8):467-476
This study brings together the research focused on science education through project-based learning (PBL). This learning project was carried out in a rural learning community and an attempt was made to adapt to the natural resources of the area by organizing educational outings, experimental activities, and encouraging the participation of families. The overall objective is to test the effectiveness of applying the PBL teaching methodology for learning science in a rural learning community. The methodology used has been qualitative, specifically, the participating research has been used and the information has been compiled in a field notebook. The results show that the didactic proposal had good results; showing that, in conclusion, science teaching today should be inclined toward more innovative educational methodologies such as PBL. 相似文献