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91.
Application of Sequential Learning Neural Networks to Civil Engineering Modeling Problems 总被引:1,自引:0,他引:1
A sequential orthogonal approach to the building and training of a single hidden layer neural network is presented in this
paper. The Sequential Learning Neural Network (SLNN) model proposed by Zhang and Morris [1]is used in this paper to tackle
the common problem encountered by the conventional Feed Forward Neural Network (FFNN) in determining the network structure
in the number of hidden layers and the number of hidden neurons in each layer. The procedure starts with a single hidden neuron
and sequentially increases in the number of hidden neurons until the model error is sufficiently small. The classical Gram–Schmidt
orthogonalization method is used at each step to form a set of orthogonal bases for the space spanned by output vectors of
the hidden neurons. In this approach it is possible to determine the necessary number of hidden neurons required. However,
for the problems investigated in this paper, one hidden neuron itself is sufficient to achieve the desired accuracy. The neural
network architecture has been trained and tested on two practical civil engineering problems – soil classification, and the
prediction o strength and workability of high performance concrete. 相似文献
92.
Santhi K Dhanaraj SA Rajendran SD Raja K Ponnusankar S Suresh B 《Drug development and industrial pharmacy》1999,25(4):547-551
The stability of liposomes after introduction into the body is presently being discussed and needs thorough understanding. Hence, as a nonliposomal approach, egg albumin nanospheres were prepared by the pH-coacervation method, and a preliminary study was carried out of the influence of process variables on the size and shape of nanospheres by changing the pH of the albumin solution, concentration of albumin solution, and volume of cross-linking agent. The batch prepared with an albumin medium of pH 9, 2% concentration, and 100 μl of 4% glutaraldehyde-ethanol solution was found to have a spherical uniform shape with an average size of 497.6 nm. The ideal batch was loaded with the systemic antifungal drug amphotericin-B. Drug-loaded nanospheres were evaluated to study their in vitro release. They were found to exhibit a biphasic pattern with a cumulative percentage release of 97.7%. 相似文献
93.
Ab initio calculations have been performed to determine the energetics of oxygen atoms adsorbed onto graphene planes and the possible reaction path extracting carbon atoms in the form of carbon monoxide. From the energetics it is confirmed that this reaction path will not significantly contribute to the gasification of well ordered carbonaceous chars. Modelling results which explore this limit are presented. 相似文献
94.
We discuss the design and implementation of network and transport layer protocols for mobile networking. The network architecture used is unique in that it separates the mobile network(s) from fixed networks and provides connectivity between the two via special gateways. These gateways split all transport connections and provide QoS guarantees to mobile users for all their open connections. We provide summaries of our protocols and discuss possible improvements. 相似文献
95.
Recently scientists have investigated what statistical distributions can be used to describe the distribution of the number
of authors per article.Ajiferuke has undertaken the most comprehensive study of this problem. He has found that by and large the Inverse Gaussian-Poisson
distribution could describe most properly the observed authorship distributions. However, it is well known that this distribution
is rather intricate, soRousseau tried to fit some simple one-parameter distributions to the number of authors of LIS articles. He has found that the geometric
and the truncated Poisson distribution adequately describe these authorship data sets. The main purpose of the present paper
is to continue these investigations and to analyse and test the viability of simple statistical distributions. As to (sub)fields
where the single author dominates the results ofRousseau were corroborated: the truncated Poisson and the geometric distribution give often adequate fits to describe the number of
authors. The Lotka distribution should be rejected. The truncated binomial distribution and the truncated negative binomial
were investigated as well. However, it is not clear whether they are acceptable candidates. 相似文献
96.
This paper presents two simple algorithms for computing the point-to-point congestion probability in a switched communication network. Methods are straightforward and can easily be computerized. Examples illustrate the methods. 相似文献
97.
Bajpai-Dikshit J Suresh AK Venkatesh KV 《Journal of Bioscience and Bioengineering》2003,96(5):481-486
A comprehensive model was developed to simulate Lactobacillus rhamnosus growth on a medium containing multiple limiting carbon sources. The strategy of optimizing specific growth rate to predict growth on multiple substrates was demonstrated. The model predictions were based on parameters obtained from L. rhamnosus growth on individual substrates. The model was able to simulate the growth, substrate consumption, product formation and specific growth rate profiles of L. rhamnosus accurately. The model prediction that co-metabolism of glucose and pyruvate enhances growth rate of and flavor production by the bacterium was experimentally verified. 相似文献
98.
99.
This paper is a modified version of a lecture which describes the synthesis, structure and reactivity of some neutral molecules of stellar significance. The neutrals are formed in the collision cell of a mass spectrometer following vertical Franck-Condon one electron oxidation of anions of known bond connectivity. Neutrals are characterised by conversion to positive ions and by extensive theoretical studies at the CCSD(T)/aug-cc-pVDZ//B3LYP/6-31G(d) level of theory. Four systems are considered in detail, viz (i) the formation of linear C(4) and its conversion to the rhombus C(4), (ii) linear C(5) and the atom scrambling of this system when energised, (iii) the stable cumulene oxide CCCCCO, and (iv) the elusive species O(2)C-CO. This paper is not intended to be a review of interstellar chemistry: examples are selected from our own work in this area. 相似文献
100.
A. Srirama Rao B. R. Phanikumar R. Dayakar Babu K. Suresh 《Canadian Metallurgical Quarterly》2007,133(5):531-538
Granular pile anchors (GPA) are one of the recent innovative foundation techniques devised for mitigating the problems posed by swelling clay beds. In a granular pile anchor, the footing is anchored to an anchor plate at the bottom of the granular pile. This makes the granular pile tension resistant and enables it to absorb the tensile force caused on the foundation by the swelling clay. An understanding of the amount of uplift resistance offered by the GPA is important in the design of granular pile-anchor foundations in field situations causing tensile forces on foundations, such as in expansive clay beds. This paper presents the results of a field-scale test program conducted to study the pullout response of GPAs embedded in expansive clay beds. Pullout load tests were conducted on GPAs of varying lengths and diameters. It was found from the field pullout load tests that granular pile anchors of larger surface area resulted in higher pullout capacity. Of the various single granular pile anchors with l/d values between 2.5 and 10, the GPA of length 1000?mm and diameter 200?mm (l/d = 5) showed the best pullout load response when tested alone, resulting in a failure uplift capacity of 14.71?kN. Increase in diameter and length of granular pile anchor increased the uplift capacity. When the length of the GPA was increased from 500 to 750 and 1000?mm, the percentage increase in the uplift load required for an upward movement of 25?mm was 33.3 and 55.5% respectively. The pullout load of the GPA when tested under group was 18?kN as against a 12?kN for the GPA when tested single. 相似文献