SAVSDN: A Scene-Aware Video Spark Detection Network for Aero Engine Intelligent Test

Due to carbon deposits, lean flames, or damaged metal parts, sparks can occur in aero engine chambers. At present, the detection of such sparks deeply depends on laborious manual work. Considering that interference has the same features as sparks, almost all existing object detectors cannot replace humans in carrying out high-precision spark detection. In this paper, we propose a scene-aware spark detection network, consisting of an information fusion-based cascading video codec-image object detector structure, which we name SAVSDN. Unlike video object detectors utilizing candidate boxes from adjacent frames to assist in the current prediction, we find that efforts should be made to extract the spatio-temporal features of adjacent frames to reduce over-detection. Visualization experiments show that SAVSDN can learn the difference in spatio-temporal features between sparks and interference. To solve the problem of a lack of aero engine anomalous spark data, we introduce a method to generate simulated spark images based on the Gaussian function. In addition, we publish the first simulated aero engine spark data set, which we name SAES. In our experiments, SAVSDN far outperformed state-of-the-art detection models for spark detection in terms of five metrics.

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Difference Fourier Analysis of Glucose Embedded and Frozen Hydrated Purple Membrane

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100053164 ◽

1982 ◽

Vol 40 ◽

pp. 74-75

Author(s):

Jules S. Jaffe ◽

Robert M. Glaeser

Keyword(s):

Purple Membrane ◽

Data Set ◽

High Resolution Data ◽

X Ray ◽

X Ray Crystallography ◽

Fourier Techniques ◽

Versus Protein ◽

The Difference ◽

Difference Fourier ◽

Ideal Method

Although difference Fourier techniques are standard in X-ray crystallography it has only been very recently that electron crystallographers have been able to take advantage of this method. We have combined a high resolution data set for frozen glucose embedded Purple Membrane (PM) with a data set collected from PM prepared in the frozen hydrated state in order to visualize any differences in structure due to the different methods of preparation. The increased contrast between protein-ice versus protein-glucose may prove to be an advantage of the frozen hydrated technique for visualizing those parts of bacteriorhodopsin that are embedded in glucose. In addition, surface groups of the protein may be disordered in glucose and ordered in the frozen state. The sensitivity of the difference Fourier technique to small changes in structure provides an ideal method for testing this hypothesis.

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A data acquisition setup for data driven acoustic design

Building Acoustics ◽

10.1177/1351010x20986901 ◽

2021 ◽

pp. 1351010X2098690

Author(s):

Romana Rust ◽

Achilleas Xydis ◽

Kurt Heutschi ◽

Nathanael Perraudin ◽

Gonzalo Casas ◽

...

Keyword(s):

Data Acquisition ◽

Interdisciplinary Approach ◽

Computational Design ◽

Surface Structures ◽

Future Research ◽

Data Set ◽

Process Measures ◽

First Results ◽

Spatio Temporal ◽

Automated Data Acquisition

In this paper, we present a novel interdisciplinary approach to study the relationship between diffusive surface structures and their acoustic performance. Using computational design, surface structures are iteratively generated and 3D printed at 1:10 model scale. They originate from different fabrication typologies and are designed to have acoustic diffusion and absorption effects. An automated robotic process measures the impulse responses of these surfaces by positioning a microphone and a speaker at multiple locations. The collected data serves two purposes: first, as an exploratory catalogue of different spatio-temporal-acoustic scenarios and second, as data set for predicting the acoustic response of digitally designed surface geometries using machine learning. In this paper, we present the automated data acquisition setup, the data processing and the computational generation of diffusive surface structures. We describe first results of comparative studies of measured surface panels and conclude with steps of future research.

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Event detection of different English data sources based on transfer learning

Journal of Intelligent & Fuzzy Systems ◽

10.3233/jifs-189798 ◽

2021 ◽

pp. 1-11

Author(s):

Yanan Huang ◽

Yuji Miao ◽

Zhenjing Da

Keyword(s):

Transfer Learning ◽

Event Detection ◽

Visual Analysis ◽

Learning Algorithm ◽

Data Sources ◽

Data Set ◽

Data Source ◽

Single Data Source ◽

The Difference ◽

Single Data

The methods of multi-modal English event detection under a single data source and isomorphic event detection of different English data sources based on transfer learning still need to be improved. In order to improve the efficiency of English and data source time detection, based on the transfer learning algorithm, this paper proposes multi-modal event detection under a single data source and isomorphic event detection based on transfer learning for different data sources. Moreover, by stacking multiple classification models, this paper makes each feature merge with each other, and conducts confrontation training through the difference between the two classifiers to further make the distribution of different source data similar. In addition, in order to verify the algorithm proposed in this paper, a multi-source English event detection data set is collected through a data collection method. Finally, this paper uses the data set to verify the method proposed in this paper and compare it with the current most mainstream transfer learning methods. Through experimental analysis, convergence analysis, visual analysis and parameter evaluation, the effectiveness of the algorithm proposed in this paper is demonstrated.

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Fire Detection Based on Fractal Analysis and Spatio-Temporal Features

Fire Technology ◽

10.1007/s10694-021-01129-7 ◽

2021 ◽

Author(s):

Monir Torabian ◽

Hossein Pourghassem ◽

Homayoun Mahdavi-Nasab

Keyword(s):

Fractal Analysis ◽

Fire Detection ◽

Temporal Features ◽

Spatio Temporal

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Mapping the Spatial-Temporal Dynamics of Vegetation Response Lag to Drought in a Semi-Arid Region

Remote Sensing ◽

10.3390/rs11161873 ◽

2019 ◽

Vol 11 (16) ◽

pp. 1873 ◽

Cited By ~ 6

Author(s):

Li Hua ◽

Huidong Wang ◽

Haigang Sui ◽

Brian Wardlow ◽

Michael J. Hayes ◽

...

Keyword(s):

Vegetation Index ◽

Temporal Dynamics ◽

Risk Mitigation ◽

Scientific Information ◽

Gaussian Function ◽

Drought Risk ◽

Severe Drought ◽

Similar Response ◽

Vegetation Types ◽

Data Set

Drought, as an extreme climate event, affects the ecological environment for vegetation and agricultural production. Studies of the vegetative response to drought are paramount to providing scientific information for drought risk mitigation. In this paper, the spatial-temporal pattern of drought and the response lag of vegetation in Nebraska were analyzed from 2000 to 2015. Based on the long-term Daymet data set, the standard precipitation index (SPI) was computed to identify precipitation anomalies, and the Gaussian function was applied to obtain temperature anomalies. Vegetation anomaly was identified by dynamic time warping technique using a remote sensing Normalized Difference Vegetation Index (NDVI) time series. Finally, multilayer correlation analysis was applied to obtain the response lag of different vegetation types. The results show that Nebraska suffered severe drought events in 2002 and 2012. The response lag of vegetation to drought typically ranged from 30 to 45 days varying for different vegetation types and human activities (water use and management). Grasslands had the shortest response lag (~35 days), while forests had the longest lag period (~48 days). For specific crop types, the response lag of winter wheat varied among different regions of Nebraska (35–45 days), while soybeans, corn and alfalfa had similar response lag times of approximately 40 days.

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Magnetotelluric static shift: Estimation and removal using the cokriging method

Geophysics ◽

10.1190/1.2400625 ◽

2007 ◽

Vol 72 (1) ◽

pp. F25-F34 ◽

Cited By ~ 11

Author(s):

Benoit Tournerie ◽

Michel Chouteau ◽

Denis Marcotte

Keyword(s):

Apparent Resistivity ◽

A Priori ◽

Shift Factor ◽

Static Shift ◽

Geostatistical Model ◽

Data Set ◽

Resistivity Sounding ◽

The Difference ◽

Cross Variogram

We present and test a new method to correct for the static shift affecting magnetotelluric (MT) apparent resistivity sounding curves. We use geostatistical analysis of apparent resistivity and phase data for selected periods. For each period, we first estimate and model the experimental variograms and cross variogram between phase and apparent resistivity. We then use the geostatistical model to estimate, by cokriging, the corrected apparent resistivities using the measured phases and apparent resistivities. The static shift factor is obtained as the difference between the logarithm of the corrected and measured apparent resistivities. We retain as final static shift estimates the ones for the period displaying the best correlation with the estimates at all periods. We present a 3D synthetic case study showing that the static shift is retrieved quite precisely when the static shift factors are uniformly distributed around zero. If the static shift distribution has a nonzero mean, we obtained best results when an apparent resistivity data subset can be identified a priori as unaffected by static shift and cokriging is done using only this subset. The method has been successfully tested on the synthetic COPROD-2S2 2D MT data set and on a 3D-survey data set from Las Cañadas Caldera (Tenerife, Canary Islands) severely affected by static shift.

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Kinematic Adaptive Frequency Sampling Combined Spatio Temporal Features for Snow Monitoring in Aerospace Applications

Expert Systems with Applications ◽

10.1016/j.eswa.2021.115472 ◽

2021 ◽

pp. 115472

Author(s):

Parameshwaran Ramalingam ◽

Lakshminarayanan Gopalakrishnan ◽

Manikandan Ramachandran ◽

Rizwan Patan

Keyword(s):

Aerospace Applications ◽

Temporal Features ◽

Frequency Sampling ◽

Spatio Temporal

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What Countries Select More Experienced Leaders? The PolEx Measure of Political Experience

British Journal of Political Science ◽

10.1017/s0007123421000107 ◽

2021 ◽

pp. 1-10

Author(s):

Alexander Baturo ◽

Johan A. Elkink

Keyword(s):

Career Paths ◽

Latent Variable ◽

Empirical Studies ◽

Future Research ◽

Variable Model ◽

Data Set ◽

Political Experience ◽

National Leaders ◽

Regime Types ◽

The Difference

Abstract How can one assess which countries select more experienced leaders for the highest office? There is wide variation in prior career paths of national leaders within, and even more so between, regime types. It is therefore challenging to obtain a truly comparative measure of political experience; empirical studies have to rely on proxies instead. This article proposes PolEx, a measure of political experience that abstracts away from the details of career paths and generalizes based on the duration, quality and breadth of an individual's experience in politics. The analysis draws on a novel data set of around 2,000 leaders from 1950 to 2017 and uses a Bayesian latent variable model to estimate PolEx. The article illustrates how the new measure can be used comparatively to assess whether democracies select more experienced leaders. The authors find that while on average they do, the difference with non-democracies has declined dramatically since the early 2000s. Future research may leverage PolEx to investigate the role of prior political experience in, for example, policy making and crisis management.

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Effect of Flaw Dimensions on Ductile Fracture Behavior of Non-Aligned Multiple Flaws in a Plate

ASME 2011 Pressure Vessels and Piping Conference: Volume 1 ◽

10.1115/pvp2011-57559 ◽

2011 ◽

Cited By ~ 1

Author(s):

Katsumasa Miyazaki ◽

Kunio Hasegawa ◽

Koichi Saito

Keyword(s):

Ductile Fracture ◽

Flat Plate ◽

Fracture Behavior ◽

Maximum Load ◽

Surface Flaws ◽

Fracture Tests ◽

The Difference ◽

Almost All ◽

Maximum Minimum

The fitness-for-service codes require the characterization of non-aligned multiple flaws for flaw evaluation, which is performed using a flaw proximity rule. Worldwide, almost all such codes provide their own proximity rule, often with unclear technical bases of the application of proximity rule to ductile or fully plastic fracture. In particular, the effect of flaw dimensions of multiple surface flaws on fully plastic fracture of non-aligned multiple flaws had not been clear. To clarify the effect of the difference of part through-wall and through-wall flaws on the behavior of fully plastic fracture, the fracture tests of flat plate specimens with non-aligned multiple part through-wall flaws were conducted. When the flaw depth a was shallow with 0.4 in ratio of a to thickness t, the maximum load Pmax occurred at penetration of multiple flaws and the effect of vertical distance of non-aligned multiple flaws H on Pmax was not so significant. However, when flaw depth was deep with 0.8 in a/t, Pmax occurred after penetration of flaws and the effect of H on Pmax could be seen clearly. It was judged that the through-wall flaw tests were appropriate for discussion of the effect of H on Pmax and the alignment rule of multiple flaws. In addition, in order to clarify the appropriate length parameter to estimate Pmax of test specimens with dissimilar non-aligned through-wall multiple flaws, the fracture tests of plate specimens were also conducted. The effect of different flaw length on Pmax was discussed with maximum, minimum and averages of dissimilar non-aligned multiple flaw lengths. Experimental results showed that the maximum length lmax would be an appropriate length parameter to estimate Pmax, when the non-aligned multiple through-wall flaws were dissimilar.

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