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61.
The Morgantown Personal Rapid Transit System is a fully automated, collection and distribution, origin to destination, non-stop transportation system. The system consists of a feet of 73 electrically powered, rubber tired, passenger carrying vehicles, operating on a dedicated guideway network at 15 second headways. The system provides a safe, comfortable non-polluting, reliable means of public transportation between the Central Business District of Morgantown, West Virginia, and the three separated campuses of West Virginia University.
This paper will address the unique application of computers in operating a public transit system which is considered the first of its kind anywhere in the world. 相似文献
62.
Pseudomonas aeruginosa can cause infections in AIDS patients who frequently do not have the usual predisposing conditions such as neutropenia and intravenous drug use. The infections due to P. aeruginosa may be difficult to treat in AIDS patients. Sinusitis has been increasingly recognized as a complication in patients with AIDS. This article describes a case of recurrent P. aeruginosa sinusitis which, until recently, was rarely reported in AIDS. 相似文献
63.
S. H. Kandil M. E. Kassem A. M. El-Khatib T. A. Ramadan M. M. Darwish 《Journal of Materials Science》1994,29(9):2513-2520
Structural defects were introduced in lithium ammonium sulphate crystals (LAS) either in the process of crystal growth (in the form of foreign ions) or by neutron irradiation. The effect of such defects on the thermal properties of LAS crystals was studied in the temperature range 300–500 K. It was assumed that the doped LAS crystals are composed of a two-phase system having different thermal parameters in each phase. The specific heat at constant pressure, C
p, of irradiated samples was found to decrease with increasing irradiation doses. The thermal expansion of LAS crystals was found to be dependent on neutron irradiation, and was attributed to two processes: the release of new species and the trapping process. 相似文献
64.
AA Ramadan 《Canadian Metallurgical Quarterly》1976,20(6):579-583
Samples of seed oil of prickly lettuce (Lactuca Sacriola oleifera) which had been obtained by pressing or by extracting with acetone, ethyl ether, petroleum ether or carbon tetrachloride were analysed for the following parameters: viscosity, saponification number, iodine number, thiocyanogen value, unsaponifiable matter, free fatty acids, peroxide number and fatty acid composition. The different parameters varied in part considerably in relation to the method of production (pressing or solvent extraction) and to the solvent. It is tried to interprete these relationships. 相似文献
65.
The solar chimney is a simple and practical idea that is applied to enhance space natural ventilation. The chimney could be vertical or inclined. The chimney inclination angle is an important parameter that greatly affects space flow pattern and ventilation rate.In the present study, the effect of chimney inclination angle on air change per hour and indoor flow pattern was numerically and analytically investigated. A numerical simulation using Ansys, a FEM-based code, was used to predict flow pattern. Then the results were compared with published experimental measurements. A FORTRAN program was developed to iteratively solve the mathematical model that was obtained through an overall energy balance on the solar chimney.The analytical results showed that an optimum air flow rate value was achieved when the chimney inclination is between 45° and 70° for latitude of 28.4°. The numerically predicted flow pattern inside the space supports this finding. Moreover, in the present study a correlation to predict the air change per hour was developed. The correlation was tested within a solar intensity greater than or equal to 500 W/m2, and chimney width from 0.1 m to 0.35 m for different inclination angles with acceptable values. 相似文献
66.
In this paper, the parallel implementation of the stretched coordinate perfectly matched layer (SC-PML) and the wave equation
PML (WE-PML) formulations is presented for truncating three-dimensional (3-D) finite difference time domain (FDTD) grids.
In the proposed parallel algorithms, the FDTD computational domain is divided into contiguous non-overlapping subdomains using
two-dimensional topology and the interprocessor communications between the neighboring subdomains are carried out by using
the message passing interface (MPI) system. The performance of the proposed parallel algorithms has been studied by using
a point source radiating in 3-D domains and performed on a network of PCs interconnected with Ethernet. It has been observed
that the WE-PML parallel algorithm is approximately 2.3 faster than the SC-PML parallel algorithm. 相似文献
67.
Ramadan SS Heyn C Mackenzie LT Chambers AF Rutt BK Foster PJ 《Magma (New York, N.Y.)》2008,21(4):251-259
INTRODUCTION: The use of MRI with iron-based magnetic nanoparticles for imaging cells is a rapidly growing field of research. We have recently reported that single iron-labeled cells could be detected, as signal voids, in vivo in mouse brains using a balanced steady-state free precession imaging sequence (b-SSFP) and a customized microimaging system at 1.5 T. METHODS: In the current study we assess the benefits, and challenges, of using a higher magnetic field strength for imaging iron-labeled cells with b-SSFP, using ex vivo mouse brain specimens imaged with near identical systems at 1.5 and 3.0 T. RESULTS: The substantial banding artifact that appears in 3 T b-SSFP images was readily minimized with RF phase cycling, allowing for banding-free b-SSFP images to be compared between the two field strengths. This study revealed that with an optimal 3 T b-SSFP imaging protocol, more than twice as many signal voids were detected as with 1.5 T. CONCLUSION: There are several factors that contributed to this important result. First, a greater-than-linear SNR gain was achieved in mouse brain images at 3 T. Second, a reduction in the bandwidth, and the associated increase in repetition time and SNR, produced a dramatic increase in the contrast generated by iron-labeled cells. 相似文献
68.
Swindle P Ramadan S Stanwell P McCredie S Russell P Mountford C 《Magma (New York, N.Y.)》2008,21(6):423-434
Proton magnetic resonance spectroscopy (MRS) is used to compare the chemistry of the transition, central and peripheral zones
of the prostate. The assignments are made using two-dimensional correlated spectroscopy and the results compared with histopathology.
The chemistry associated with benign prostatic hyperplasia (BPH), prostate intraepithelial neoplasia (PIN) and malignant biopsy
tissues are described. There are distinct MR spectral patterns for glandular and stromal BPH, PIN and adenocarcinoma. Importantly,
there are also different spectral patterns from BPH in the transitional and central zones when compared to BPH in the peripheral
zone. A pattern recognition method is used to analyze the MR spectra from the biopsy specimens. The resultant mathematical
classifiers generated a high level of accuracy (sensitivity and specificity of 100 and 97%). It was found that for this accuracy
to be achieved, the classifiers need to be developed by comparing the spectra with specialist serial sectioned histopathology.
With serial sectioned pathology the pattern recognition method was capable of identifying less than 5% of adenocarcinoma in
a given piece of tissue. Many of the chemicals identified in the biopsy specimens are available for inspection from the prostate,
in vivo, at 3 T. 相似文献
69.
70.
Introduction of artificial neural network (ANN) into the field of GMO detection is the aim of this investigation. The usefulness
of ANN to predict transgenic maize (Bt-176) based on chemical composition of the extracted crude oil was evaluated. The training
set, comprised of a composition of major and minor lipid components as inputs and outputs. Crude oil extracted from the genetically
modified maize (Bt-176) and non-transgenic maize was characterized in terms of its fatty acids, phytosterols and tocopherols
distribution as well as of its lipid classes and unsaponifiables amounts. The results obtained from lipid distribution analysis
showed that the grains of Bt-176 maize were comparable in their composition to that of the control maize. The analytical data
have been elaborated by supervised pattern recognition technique ANN in order to classify genetically modified maize (Bt-176)
and conventional maize as well as to authenticate the origin of the samples. 相似文献