The atomic force microscopy (AFM) is an important innovation in the sample imaging fields, the signals extracted from the AFM such as the force as function of the indentation and the friction as function of the indent...
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ISBN:
(纸本)9781467365161
The atomic force microscopy (AFM) is an important innovation in the sample imaging fields, the signals extracted from the AFM such as the force as function of the indentation and the friction as function of the indentation can be used to extract many chemical and mechanical properties of the sample. Nanoscientists analyze these signals manually;the aim of this article is to find new algorithms to automatically analyze AFM signals.
This study inspected and tracked the location state of a test object in the telemetry monitoring of a wafer or solar panel, and the relevant optoelectronic devices. A CCD camera, triggered by the proposed system, capt...
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This study inspected and tracked the location state of a test object in the telemetry monitoring of a wafer or solar panel, and the relevant optoelectronic devices. A CCD camera, triggered by the proposed system, captures the test target image in real time, which is transferred to the system for low-pass filtering, image binarization, spatial masking, boundary tracing, and other means of image processing. The new edge point detection algorithm is then applied to identify the edge points of three parallel lines. Three different group edge points are determined using the edge point detection algorithm, and the three groups are computed using a single linear regression equation. Multiple-linear regression is conducted to obtain the sections of straight lines of the groups that can best satisfy the expected requirements. Finally, whether the detection results are consistent with the expected requirements is determined to inspect whether the test object is consistent with the process specifications in order to reduce undesirable losses, as caused by inappropriate placement angle in subsequent manufacturing, thus, enhancing subsequent manufacturing to achieve high yield. (C) 2013 Elsevier GmbH. All rights reserved.
In the present work, an Auto Regressive Moving Average (ARMA) model and a Discrete Wavelet Transform (DWT) are applied on vibrational signals, acquired by an accelerometer placed on the cylinder block of a Spark Ignit...
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Plasma depletions (or bubbles) are strong reductions in the ionospheric F-region plasma density due to the appearance of a Rayleigh-Taylor instability in the post-sunset, producing severe radio signal disruptions when...
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Plasma depletions (or bubbles) are strong reductions in the ionospheric F-region plasma density due to the appearance of a Rayleigh-Taylor instability in the post-sunset, producing severe radio signal disruptions when crossing them. Most of the plasma depletions are confined on the Appleton Anomaly region, which also shows the presence of strong scintillations activity. Therefore, stations located in the vicinity of the geomagnetic equator are expected to be frequently affected by the presence of plasma depletions. This paper provides a comparison between the plasma depletion detection results achieved using two algorithms: one developed by the National Institute for Aerospace Technology and the University Complutense of Madrid and one developed by GMV. Six equatorial stations distributed all over the world and different solar activity and seasonal conditions have been selected to analyze the algorithms' response to different plasma depletions characteristics. A regional behavior analysis of the plasma depletion occurrence and characteristics is also provided. (C) 2013 Elsevier Ltd. All rights reserved.
In this paper, we consider the impact of cyber attacks on voltage regulation in distribution systems. We employ a centralized control scheme which utilizes voltage measurements from sectionizing switches equipped with...
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ISBN:
(纸本)9781479949342
In this paper, we consider the impact of cyber attacks on voltage regulation in distribution systems. We employ a centralized control scheme which utilizes voltage measurements from sectionizing switches equipped with sensors for connecting distributed generation. Through detailed case studies by simulations, it is demonstrated that if measurements are falsified by an attacker, voltage violation can occur in the system. However, by equipping the control with a detection algorithm, we verify that the damage can be limited especially when the number of attacked sensors is small. Further discussion is provided on how to enhance the security level of the proposed algorithm.
A key challenge for standoff explosive sensors is to distinguish explosives, with high confidence, from a myriad of unknown background materials that may have interfering spectral peaks. To meet this challenge a senso...
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ISBN:
(纸本)9781628410105
A key challenge for standoff explosive sensors is to distinguish explosives, with high confidence, from a myriad of unknown background materials that may have interfering spectral peaks. To meet this challenge a sensor needs to exhibit high specificity and high sensitivity in detection at low signal-to-noise ratio levels. We had proposed a Dual-Excitation-Wavelength Resonance-Raman Detector (DEWRRED) to address this need. In our previous work, we discussed various components designed at WVHTCF for a DEWRRED sensor. In this work, we show a completely assembled laboratory prototype of a DEWRRED sensor and utilize it to detect explosives from two standoff distances. The sensor system includes two novel, compact CW deep-Ultraviolet (DUV) lasers, a compact dual-band high throughput DUV spectrometer, and a highly-sensitive detection algorithm. We choose DUV excitation because Raman intensities from explosive traces are enhanced and fluorescence and solar background are not present. The DEWRRED technique exploits the excitation wavelength dependence of Raman signal strength, arising from complex interplay of resonant enhancement, self-absorption and laser penetration depth. We show measurements from >10 explosives/pre-cursor materials at different standoff distances. The sensor showed high sensitivity in explosive detection even when the signal-to-noise ratio was close to one (similar to 1.6). We measured receiver-operating-characteristics, which show a clear benefit in using the dual-excitation-wavelength technique as compared to a single-excitation-wavelength technique. Our measurements also show improved specificity using the amplitude variation information in the dual-excitation spectra.
In this paper, we investigate the problem of detecting-time epochs when zero-velocity updates can be applied in a foot-mounted inertial navigation (motion-tracking) system. We examine three commonly used detectors: th...
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In this paper, we investigate the problem of detecting-time epochs when zero-velocity updates can be applied in a foot-mounted inertial navigation (motion-tracking) system. We examine three commonly used detectors: the acceleration-moving variance detector, the acceleration-magnitude detector, and the angular rate energy detector. We demonstrate that all detectors can be derived within the same general likelihood ratio test (LRT) framework, given the different prior knowledge about the sensor signals. Further, by combining all prior knowledge, we derive a new LRT detector. Subsequently, we develop a methodology to evaluate the performance of the detectors. Employing the developed methodology, we evaluate the performance of the detectors using leveled ground, slow (approximately 3 km/h) and normal (approximately 5 km/h) gait data. The test results are presented in terms of detection versus false-alarm probability. Our preliminary results show that the new detector performs marginally better than the angular rate energy detector that outperforms both the acceleration-moving variance detector and the acceleration-magnitude detector.
The design and development of a Bottom Pressure Recorder for a Tsunami Early Warning System is described here. The special requirements that it should satisfy for the specific application of deployment at ocean bed an...
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The design and development of a Bottom Pressure Recorder for a Tsunami Early Warning System is described here. The special requirements that it should satisfy for the specific application of deployment at ocean bed and pressure monitoring of the water column above are dealt with. A high-resolution data digitization and low circuit power consumption are typical ones. The implementation details of the data sensing and acquisition part to meet these are also brought out. The data processing part typically encompasses a Tsunami detection algorithm that should detect an event of significance in the background of a variety of periodic and aperiodic noise signals. Such an algorithm and its simulation are presented. Further, the results of sea trials carried out on the system off the Chennai coast are presented. The high quality and fidelity of the data prove that the system design is robust despite its low cost and with suitable augmentations, is ready for a full-fledged deployment at ocean bed. (C) 2013 Elsevier Ltd. All rights reserved.
In order to achieve automatic detection of the tile flatness and automatic classification of product quality, the top control unit is touch screen, which can download parameters, display result information, control an...
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ISBN:
(纸本)9783037859087
In order to achieve automatic detection of the tile flatness and automatic classification of product quality, the top control unit is touch screen, which can download parameters, display result information, control and debug device. Lower machine works as follows, when the tile is transferred to the test platform in the correct position, the laser displacement sensor collects 25 characteristic points information from moving the tile surface, via the A / D module,the information is converted into digital signals, according to specific flatness algorithm, PLC calculates flatness and achieves tile classification. Practice shows that the accuracy of tile flatness is 0.1mm, detection efficiency is 40 pieces per-minute. The system is suitable the quality control of ceramic tile product.
Amino acid repeats (AARs) are abundant in protein sequences. They have particular roles in protein function and evolution. Simple repeat patterns generated by DNA slippage tend to introduce length variations and point...
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Amino acid repeats (AARs) are abundant in protein sequences. They have particular roles in protein function and evolution. Simple repeat patterns generated by DNA slippage tend to introduce length variations and point mutations in repeat regions. Loss of normal and gain of abnormal function owing to their variable length are potential risks leading to diseases. Repeats with complex patterns mostly refer to the functional domain repeats, such as the well-known leucine-rich repeat and WD repeat, which are frequently involved in protein-protein interaction. They are mainly derived from internal gene duplication events and stabilized by 'gate-keeper' residues, which play crucial roles in preventing inter-domain aggregation. AARs are widely distributed in different proteomes across a variety of taxonomic ranges, and especially abundant in eukaryotic proteins. However, their specific evolutionary and functional scenarios are still poorly understood. Identifying AARs in protein sequences is the first step for the further investigation of their biological function and evolutionary mechanism. In principle, this is an NP-hard problem, as most of the repeat fragments are shaped by a series of sophisticated evolutionary events and become latent periodical patterns. It is not possible to define a uniform criterion for detecting and verifying various repeat patterns. Instead, different algorithms based on different strategies have been developed to cope with different repeat patterns. In this review, we attempt to describe the amino acid repeat-detection algorithms currently available and compare their strategies based on an in-depth analysis of the biological significance of protein repeats.
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