scholarly journals There and back again – a zebra's tale

2020 ◽  
Vol 223 (23) ◽  
pp. jeb232140
Author(s):  
Hattie Bartlam-Brooks ◽  
Simon Wilshin ◽  
Tatjana Hubel ◽  
Stephen Hailes ◽  
Emily Bennitt ◽  
...  
Keyword(s):  
Angular Distribution ◽  
Confidence Interval ◽  
High Accuracy ◽  
Gps Data ◽  
Multiple Routes ◽  
Plains Zebra ◽  
Better Than

ABSTRACTAnimals need to navigate between resources such as water, food and shelter, and how they achieve this is likely to vary with species. Here, using high-accuracy GPS data, we studied repeated journeys made by wild plains zebra (Equus quagga) through a naturally vegetated environment to explore whether they consistently follow the same route through the area or whether they use a range of routes to reach their goal. We used a model to distinguish and quantify these two possibilities and show that our observations are consistent with the use of multiple routes. Our model performs better than assuming a uniform angular distribution of trajectories. The typical separation of the routes was found to be small (1.96 m), while the scale at which neighbouring trajectories are informative to direction of travel was found to be large (with a confidence interval of 1.19–26.4 m). Our observations are consistent with the hypothesis that zebra are able to navigate without having to return to previously used routes, instead using numerous different routes of similar trajectories.

Using Connectionist Modules for Decision Support

1990 ◽  
Vol 29 (03) ◽  
pp. 167-181 ◽  
Author(s):  
G. Hripcsak
Keyword(s):  
Decision Support ◽  
Standard Deviation ◽  
Confidence Interval ◽  
Posterior Probability ◽  
Back Propagation ◽  
Connectionist Model ◽  
Test Set ◽  
The Third ◽  
Independent Test ◽  
Better Than

AbstractA connectionist model for decision support was constructed out of several back-propagation modules. Manifestations serve as input to the model; they may be real-valued, and the confidence in their measurement may be specified. The model produces as its output the posterior probability of disease. The model was trained on 1,000 cases taken from a simulated underlying population with three conditionally independent manifestations. The first manifestation had a linear relationship between value and posterior probability of disease, the second had a stepped relationship, and the third was normally distributed. An independent test set of 30,000 cases showed that the model was better able to estimate the posterior probability of disease (the standard deviation of residuals was 0.046, with a 95% confidence interval of 0.046-0.047) than a model constructed using logistic regression (with a standard deviation of residuals of 0.062, with a 95% confidence interval of 0.062-0.063). The model fitted the normal and stepped manifestations better than the linear one. It accommodated intermediate levels of confidence well.

A Design of High-Accuracy Displacement Measurement Instrument from Principles of Optics

2012 ◽  
Vol 170-173 ◽  
pp. 2924-2928
Author(s):  
Sheng Biao Chen ◽  
Yun Zhi Tan
Keyword(s):  
Measurement Instrument ◽  
High Accuracy ◽  
Mechanical Tests ◽  
Total Reflection ◽  
Displacement Measurement ◽  
New Method ◽  
Water Volume ◽  
Water Drainage ◽  
Accuracy Of Measurement ◽  
Better Than

In order to measure the water drainage volume in soil mechanical tests accurately, it develop a new method which is based on principles of optics. And from both physical and mathematic aspects, it deduces the mathematic relationship between micro change in displacement and the increment projected on screen. The result shows that total reflection condition is better than refraction condition. What’s more, the screen could show the water volume micro variation clearly, so it can improve the accuracy of measurement.

scholarly journals Temperature Prediction of PMSMs Using Pseudo-Siamese Nested LSTM

2021 ◽  
Vol 12 (2) ◽  
pp. 57
Author(s):  
Yongping Cai ◽  
Yuefeng Cen ◽  
Gang Cen ◽  
Xiaomin Yao ◽  
Cheng Zhao ◽  
...  
Keyword(s):  
Electric Vehicles ◽  
Simple Structure ◽  
High Accuracy ◽  
Stator Winding ◽  
High Power Density ◽  
Temperature Prediction ◽  
Permanent Magnet Synchronous Motors ◽  
Training Performance ◽  
Synchronous Motors ◽  
Better Than

Permanent Magnet Synchronous Motors (PMSMs) are widely used in electric vehicles due to their simple structure, small size, and high power-density. The research on the temperature monitoring of the PMSMs, which is one of the critical technologies to ensure the operation of PMSMs, has been the focus. A Pseudo-Siamese Nested LSTM (PSNLSTM) model is proposed to predict the temperature of the PMSMs. It takes the features closely related to the temperature of PMSMs as input and realizes the temperature prediction of stator yoke, stator tooth, and stator winding. An optimization algorithm of learning rate combined with gradual warmup and decay is proposed to accelerate the convergence during the training and improve the training performance of the model. Experimental results reveal the proposed method and Nested LSTM (NLSTM) achieves high accuracy by comparing with other intelligent prediction methods. Moreover, the proposed method is slightly better than NLSTM in temperature prediction of PMSMS.

scholarly journals High Accuracy Measurement of Total Losses in Fractional Horsepower Induction Motors

2015 ◽  
Vol 1 (2) ◽  
pp. 13
Author(s):  
Azzeddine Ferrah ◽  
Mounir Bouzguenda ◽  
Jehad M. Al-Khalaf Bani Younis
Keyword(s):  
Single Phase ◽  
Induction Motors ◽  
Data Acquisition System ◽  
High Accuracy ◽  
Industrial Applications ◽  
Motor Speed ◽  
Accuracy Measurement ◽  
Three Phase ◽  
Better Than ◽  
High Accuracy Measurement

Large and small single-phase and three-phase induction motors are commonly used in industrial applications. The present work represents an attempt towards the design of a high accuracy system for the measurement of fractional horsepower (FHP) induction motor losses and efficiency. The calorimeter designed and built is capable of measuring heat losses of up to 1 kW with an overall accuracy better than 3%. During all tests, ambient temperature, humidity, motor speed and motor frame temperature were recorded using precise digital instruments. The inlet, outlet temperatures and resulting losses were recorded automatically using a high accuracy 12-bit data acquisition system. The preliminary results obtained demonstrate the suitability of the designed calorimeter for the accurate measurement of losses in FHP induction motors.

scholarly journals Novel 500-GHz Band Waveguide Stepped Septum-Type Circular Polarizer with a New High-Accuracy and Very Small Waveguide Flange

2020 ◽  
Author(s):  
Yutaka Hasegawa ◽  
Hiroyuki Maezawa ◽  
Hideo Ogawa
Keyword(s):  
High Performance ◽  
High Accuracy ◽  
Circular Polarizer ◽  
New Methods ◽  
Position Errors ◽  
Surface Flatness ◽  
Atmospheric Observations ◽  
Dimensional Errors ◽  
Determination Mechanism ◽  
Better Than

Abstract A new waveguide stepped septum-type circular polarizer (SST-CP) was developed to operate in the 500-GHz band for radio astronomical and planetary atmospheric observations. In a previous study, we developed a practical SST-CP for the 230-GHz band. However, several issues prevent this device being easily scaled down to the 500-GHz band, such as manufacturing dimensional errors and waveguide flange position errors. In this study, we developed a new waveguide flange with a high-accuracy position determination mechanism and a very small size of 10 × 10 mm. We also developed a new fabrication technique to obtain very good flatness for the device’s blank materials by high-accuracy polishing using a resin fixture. Using these new methods, the manufactured 500-GHz band SST-CP achieved a cross-polarization talk level of better than – 30 dB at 465–505 GHz, a device surface flatness of within 3 μm, and also the horizontal positioning error of ± 3 μm. These results indicate that the developed 500-GHz band SST-CP has high performance in the high-frequency band, and thus the new manufacturing methods are effective in the 500-GHz band.

scholarly journals Differential intracellular efficacies of ciprofloxacin and cefixime against Neisseria gonorrhoeae in human fallopian tube organ culture.

1997 ◽  
Vol 41 (7) ◽  
pp. 1547-1551 ◽  
Author(s):  
J P Phanucharas ◽  
G L Gorby
Keyword(s):  
Epithelial Cells ◽  
Confidence Interval ◽  
Neisseria Gonorrhoeae ◽  
Organ Culture ◽  
Fallopian Tube ◽  
Cytochalasin D ◽  
Human Fallopian Tube ◽  
Culture Model ◽  
Better Than

This study compared the abilities of ciprofloxacin and cefixime to kill intracellular Neisseria gonorrhoeae in a human fallopian tube organ culture assay. When invasion was inhibited by cytochalasin D, 0.996% of the tissue-associated gonococci survived ciprofloxacin exposure compared to 1.70% of gonococci exposed to cefixime (95% confidence interval for the ratio of the means, 0.267 to 1.30), indicating that the two antibiotics did not significantly differ in the ability to kill extracellular attached organisms. In the absence of cytochalasin D, 1.63% survived ciprofloxacin exposure while 9.76% survived cefixime treatment (95% confidence interval for the ratio of the means, 0.067 to 0.418). These results suggest that ciprofloxacin penetrated epithelial cells and killed intracellular gonococci better than did cefixime. Thus, at concentrations achievable in serum, ciprofloxacin was more effective in total gonococcal killing than cefixime in this human fallopian tube organ culture model.

MOCUM Code Verification and Sensibility Study Using C5G7 Benchmark

2016 ◽  
Author(s):  
Xue Yang ◽  
Rajan Borse ◽  
Nader Satvat
Keyword(s):  
Method Of Characteristics ◽  
Polar Angle ◽  
Mesh Size ◽  
Sensitivity Study ◽  
High Accuracy ◽  
Benchmark Problem ◽  
Code Verification ◽  
Heterogeneous Effects ◽  
Speed Up ◽  
Better Than

This work uses the 2-D C5G7 benchmark to verify the accuracy of the MOCUM code, a parallel neutronics program based on the method of characteristics (MOC) for solving arbitrary core geometry. Compared to the MCNP results, MOCUM k-eff, maximum assembly and pin power percentage errors are 0.02%, −0.06%, and 0.64%, respectively. The results demonstrate the high accuracy of the MOCUM code. The calculation uses a total of 56 threads, and the runtime on dual Intel Xeon E5-2699 v3 CPUs is 26 minutes, with speed up higher than 50 times. The sensitivity study of various MOC parameters using the calculation of the C5G7 benchmark problem is also performed. The study reveals that C5G7 requires the usage of 48 or more azimuthal angles. The strong flux gradient and the heterogeneous effects need fine unstructured meshes to resolve. The simulation uses 258 million zones with an average mesh size of 0.016 cm2. The investigation of the polar angle quadrature indicates that Leonard polar angle performs slightly better than Gauss-Legendre and Tabuchi polar angles and more than three polar angles are not necessary. In addition, parameter sensitivity study shows that coarse parameters are prone to introduce error to the neutron flux but not k-eff.

The Stolz and ASME-AGA Orifice Equations Compared to Laboratory Data

1979 ◽  
Vol 101 (4) ◽  
pp. 483-490 ◽  
Author(s):  
R. W. Miller
Keyword(s):  
Systematic Error ◽  
Laboratory Data ◽  
High Accuracy ◽  
Laboratory Results ◽  
Using Data ◽  
The U.S ◽  
Ratio Range ◽  
Better Than

Today, technical experts in Europe and the U.S. are debating the merits of conducting new orifice flowmeter tests, establishing the effects of upstream disturbance and conducting other programs to improve orifice flowmetering accuracy. ISO has adopted a new “Universal” orifice equation proposed by J. Stolz. With over 1,000,000 orifice flowmeters in use today, any change in the coefficient value is of major concern. There are now two equations for calculating flange tap coefficients, the ASME-AGA equation and the ISO equation. They differ in form, predict different coefficients, and have different overall uncertainties (tolerance value). This paper presents a comparison between actual laboratory data and these two equations. The data were obtained in two high accuracy laboratories on flange tap orifice flowmeters fabricated by different manufacturers to AGA or ASME recommendations. Data plate dimensions were used in all calculations, and conformity to ASME or AGA requirements was the responsibility of the manufacturer. For this reason it is believed that the analysis more nearly represents what the user can expect if the in-site installation approached that of the laboratory. Results indicate that over the same beta ratio range the ISO (or Stolz) equation form is significantly better than the present ASME-AGA form. The overall uncertainty (or tolerance), although smaller than the ASME-AGA, is still ± 1 percent because of a 0.4 percent systematic error. Results of work by Miller-Kneisel, using data from three different laboratories, are presented to indicate that ±0.5 percent remains achievable; for betas up to 0.7 using the ISO (Stolz) equation form with modified coefficients.

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