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991.
Cecilia Masemola Moses Azong Cho Abel Ramoelo 《International journal of remote sensing》2016,37(18):4401-4419
The leaf area index (LAI) is the key biophysical indicator used to assess the condition of rangeland. In this study, we investigated the implications of narrow spectral response, high radiometric resolution (12 bits), and higher signal-to-noise ratio of the Landsat 8 Operational Land Imager (OLI) sensor for the estimation of LAI. The Landsat 8 LAI estimates were compared to that of its predecessors, namely Landsat 7 Enhanced Thematic Mapper Plus (ETM+) (8 bits). Furthermore, we compared the radiative transfer model (RTM) and spectral indices approaches for estimating LAI on rangeland systems in South Africa. The RTM was inverted using artificial neural network (ANN) and lookup table (LUT) algorithms. The accuracy of the models was higher for Landsat 8 OLI, where ANN (root mean squared error, RMSE = 0. 13; R2 = 0. 89), LUT (RMSE = 0. 25; R2 = 0. 50), compared to Landsat 7 ETM+, where ANN (RMSE = 0. 35; R2 = 0. 60), LUT (RMSE = 0. 38; R2 = 0. 50). Compared to an empirical approach, the RTM provided higher accuracy. In conclusion, Landsat 8 OLI provides an improvement for the estimation of LAI over Landsat 7 ETM+. This is useful for rangeland monitoring. 相似文献
992.
A new triiodothyronine (T3) radioimmunoassay kit offers simplicity of method, short incubation time, specificity, and reproducibility. 125I-labeled T3 and unknown serum (or standard) are added to alkaline buffered (pH 12.4) Sephadex G-25 columns; the T3 is freed of proteins with an alkaline buffer wash, antiserum is added, and the columns are incubated at room temperature for 2 h. "Free" hormone (i.e., unbound to antiserum) remains on the column after a second wash. The radioactivity on the column is counted and related to the total activity added. The T3 standards produced a straight line on log-logit plot; reactivity of analytical-grade thyroxine was 0.6% on weight basis; and the analytical recovery of T3 added to a T3-free serum was complete. Euthroid, hyperthyroid, and hypothyroid ranges were 0.74-2.64, 2.91-7.52, and 0-1.21 mug/liter, respectively. These values correlated well with both the clinical status of patients and with values obtained by an established radioimmunoassay method. The procedure is simply done; results may be obtained in less than 4 h. 相似文献
993.
The sonographic features of focal nodular hyperplasia of the liver as reported in the literature and nonspecific. However, a linear cluster of bright echoes was detected in the nodules of two of our patients with surgically proven focal nodular hyperplasia. Pathologically this finding correlated closely with the gross appearance of the characteristic fibrotic scar of focal nodular hyperplasia. When present, this "scar sign" should suggest the diagnosis of focal nodular hyperplasia, particularly in the typical clinical setting. 相似文献
994.
One reason that researchers may wish to demonstrate that an external software quality attribute can be measured consistently
is so that they can validate a prediction system for the attribute. However, attempts at validating prediction systems for
external subjective quality attributes have tended to rely on experts indicating that the values provided by the prediction
systems informally agree with the experts’ intuition about the attribute. These attempts are undertaken without a pre-defined
scale on which it is known that the attribute can be measured consistently. Consequently, a valid unbiased estimate of the
predictive capability of the prediction system cannot be given because the experts’ measurement process is not independent of the prediction system’s values. Usually, no justification is given for not checking to see if the experts
can measure the attribute consistently. It seems to be assumed that: subjective measurement isn’t proper measurement or subjective measurement cannot be quantified or no one knows the true values
of the attributes anyway and they cannot be estimated. However, even though the classification of software systems’ or software artefacts’ quality attributes is subjective, it
is possible to quantify experts’ measurements in terms of conditional probabilities. It is then possible, using a statistical
approach, to assess formally whether the experts’ measurements can be considered consistent. If the measurements are consistent,
it is also possible to identify estimates of the true values, which are independent of the prediction system. These values
can then be used to assess the predictive capability of the prediction system. In this paper we use Bayesian inference, Markov
chain Monte Carlo simulation and missing data imputation to develop statistical tests for consistent measurement of subjective
ordinal scale attributes. 相似文献
995.
Moses E. Ekpenyong Eno-Abasi Urua Dafydd Gibbon 《International Journal of Speech Technology》2008,11(2):87-96
In this paper we discuss the procedural problems, issues and challenges involved in developing a generic speech synthesizer
for African tone languages. We base our development methodology on the “MultiSyn” unit-selection approach, supported by Festival
Text-To-Speech (TTS) Toolkit for Ibibio, a Lower Cross subgroup of the (New) Benue-Congo language family widely spoken in
the southeastern region of Nigeria. We present in a chronological order, the several levels of infrastructural and linguistic
problems as well as challenges identified in the Local Language Speech Technology Initiative (LLSTI) during the development
process (from the corpus preparation and refinement stage to the integration and synthesis stage). We provide solutions to
most of these challenges and point to possible outlook for further refinement. The evaluation of the initial prototype shows
that the synthesis system will be useful to non-literate communities and a wide spectrum of applications. 相似文献
996.
Shape Reconstruction of 3D Bilaterally Symmetric Surfaces 总被引:1,自引:0,他引:1
Shimshoni Ilan Moses Yael Lindenbaum Michael 《International Journal of Computer Vision》2000,39(2):97-110
The paper presents a new approach for shape recovery based on integrating geometric and photometric information. We consider 3D bilaterally symmetric objects, that is, objects which are symmetric with respect to a plane (e.g., faces), and their reconstruction from a single image. Both the viewpoint and the illumination are not necessarily frontal. Furthermore, no correspondence between symmetric points is required.The basic idea is that an image taken from a general, non frontal viewpoint, under non-frontal illumination can be regarded as a pair of images. Each image of the pair is one half of the object, taken from different viewing positions and with different lighting directions. Thus, one-image-variants of geometric stereo and of photometric stereo can be used. Unlike the separate invocation of these approaches, which require point correspondence between the two images, we show that integrating the photometric and geometric information suffice to yield a dense correspondence between pairs of symmetric points, and as a result, a dense shape recovery of the object. Furthermore, the unknown lighting and viewing parameters, are also recovered in this process.Unknown distant point light source, Lambertian surfaces, unknown constant albedo, and weak perspective projection are assumed. The method has been implemented and tested experimentally on simulated and real data. 相似文献
997.
Husnu Gerengi Moses M. Solomon Gozen Bereket Kadir Goksen Mesut Yıldız 《Journal of Adhesion Science and Technology》2018,32(2):207-223
The corrosion inhibition of AA2024-T4 in 3.5% NaCl solution by 8-hydroxylquinoline (8-HQ) was investigated by potentiodynamic polarisation (PDP), electrochemical impedance spectroscopy and dynamic electrochemical impedance spectroscopy. Experimental results were supported with scanning electron microscopy (SEM), atomic force microscopy and Fourier transform-infrared (FTIR) spectroscopy analysis. It was found that 8-HQ molecules adsorbed on the alloy surface and protected it against corrosion. SEM, energy dispersive spectroscopy, and FTIR results confirm the adsorption of 8-HQ molecules on AA2024-T4. The inhibition efficiency of 8-HQ is found to increase with increase in concentration and the highest concentration studied (0.05 M) offered corrosion inhibition efficiency of 84%. PDP results show that 8-HQ acts as mixed type inhibitor in the studied medium. 相似文献
998.
Daryl Tulimieri Norbert Mulders Moses H. W. Chan 《Journal of Low Temperature Physics》1998,110(1-2):609-614
We have made torsional oscillator measurements of thin helium films on a Mylar surface preplated with 2 and 5 layers of H
2
. The minimum
4
He coverage needed for superfluidity, or inert layer, n
o
on both surfaces is found to be 6 mole/m
2
. This is equivalent to 1/2 of a monolayer at bulk liquid density. The superfluid transition in coverages above n
o
is similar to that found on bare Mylar, exhibiting the standard Kosterlitz-Thouless characteristics. We find no anomaly in
s
or the dissipation in the film that can be identified with a second transition reported in recent third sound experiments. 相似文献
999.
B Annabi H Hiraiwa BC Mansfield KJ Lei T Ubagai MH Polymeropoulos SW Moses R Parvari E Hershkovitz H Mandel M Fryman JY Chou 《Canadian Metallurgical Quarterly》1998,62(2):400-405
Glycogen-storage disease type 1 (GSD-1), also known as "von Gierke disease," is caused by a deficiency in microsomal glucose-6-phosphatase (G6Pase) activity. There are four distinct subgroups of this autosomal recessive disorder: 1a, 1b, 1c, and 1d. All share the same clinical manifestations, which are caused by abnormalities in the metabolism of glucose-6-phosphate (G6P). However, only GSD-1b patients suffer infectious complications, which are due to both the heritable neutropenia and the functional deficiencies of neutrophils and monocytes. Whereas G6Pase deficiency in GSD-1a patients arises from mutations in the G6Pase gene, this gene is normal in GSD-1b patients, indicating a separate locus for the disorder in the 1b subgroup. We now report the linkage of the GSD-1b locus to genetic markers spanning a 3-cM region on chromosome 11q23. Eventual molecular characterization of this disease will provide new insights into the genetic bases of G6P metabolism and neutrophil-monocyte dysfunction. 相似文献
1000.
Biswajit Sarkar Leopoldo Eduardo Cárdenas-Barrón Mitali Sarkar Moses Laksono Singgih 《Journal of Manufacturing Systems》2014
This paper revisits the economic production quantity (EPQ) model with rework process at a single-stage manufacturing system with planned backorders. It is well known that any imperfect production system of real life has random defective rates. In this direction, this paper extends an inventory model to allow random defective rates. Basically, three different inventory models are developed for three different distribution density functions such as uniform, triangular, and beta. The analytical derivation provides closed-form solution for each inventory model. We have made comparison tables of optimal results among the distribution functions. Some numerical examples and sensitivity analysis are given to illustrate the inventory models. 相似文献