De-Noising Method for Wayside Train Bearings Acoustic Signal Based on Doppler Shift

2013 ◽  
Vol 333-335 ◽  
pp. 504-509 ◽  
Author(s):  
Fei Hu ◽  
Chang Qing Shen ◽  
Fan Rang Kong

The noises with high level from the different positions of the train lead to the difficulty for extraction of the acoustic signal from the train bearings. Thus the de-noising should be carried out to eliminate the influence of the noises. A new de-noising method has been proposed based on the Doppler Shift. With the crazy climber detection algorithm, all the instantaneous frequencies could be extracted. According to the acoustic theory of Morse, the information of the position of these acoustic sources is revealed. Finally, the variable digital filtering was employed to remove the noises from the other positions of the train. A simulation on the signal containing with ten frequency components demonstrated the validity of this method proposed and the useful components of the signal were enhanced.

2013 ◽  
Vol 333-335 ◽  
pp. 510-515 ◽  
Author(s):  
Fei Hu ◽  
Chang Qing Shen ◽  
Fang Liu ◽  
Ao Zhang ◽  
Fan Rang Kong

The phenomenon of Doppler Shift leads to the difficulty for fault diagnosis of train bearings with a high moving speed. So the elimination of the Doppler shift should be implemented firstly. A Doppler Shift elimination method for the wayside acoustic signal is proposed. The instantaneous frequency estimation based on STFT was applied to attain the IF vector. According to the acoustic theory of Morse, the data fitting was then carried out to achieve the fitting IFs, with which the re-sampling sequence could be established to eliminate Doppler Shift. To demonstrate the validity of this method, an experiment with the synthetic signal containing several frequency components had been carried out. The results show that the re-sampled signal was revised without Doppler Shift.


1970 ◽  
Vol 1 (2) ◽  
pp. 34-36
Author(s):  
Mehedi Imam

In Bangladesh, demand for judicial independence in practice has been a much debated issue and the demand is fulfilled but expectation of people is not only limited to have an independent judiciary but to have an impartial system and cadre of people, which will administer justice rationally being free from fear or force. The independence of judiciary and the impartial judicial practice are related concepts, one cannot sustain without the other and here existence as well as the need of practicing impartiality is well recognized. But the art of practicing impartiality does not develop overnight as it’s related to development of one’s attitude. It takes a considerable time resulting from understanding, appreciating and acknowledging the moral values, ethics and professional responsibility. The judiciary includes Judges, Advocates mostly who are expected to demonstrate a high level of moral values and impartiality towards people seeking justice and ‘rule of law’. This is true that bench officers and clerks are also part of the process to ensure rule of law with same level of participation by the law enforcing agencies such as police. However the paper includes only those who either join judiciary as Judge/Magistrate or Advocate to explore level and extent of ethical knowledge they receive being key role players of the system. DOI: http://dx.doi.org/10.3329/bioethics.v1i2.9628 Bangladesh Journal of Bioethics 2010; 1(2): 34-36


Author(s):  
Priya R. Kamath ◽  
Kedarnath Senapati ◽  
P. Jidesh

Speckles are inherent to SAR. They hide and undermine several relevant information contained in the SAR images. In this paper, a despeckling algorithm using the shrinkage of two-dimensional discrete orthonormal S-transform (2D-DOST) coefficients in the transform domain along with shock filter is proposed. Also, an attempt has been made as a post-processing step to preserve the edges and other details while removing the speckle. The proposed strategy involves decomposing the SAR image into low and high-frequency components and processing them separately. A shock filter is used to smooth out the small variations in low-frequency components, and the high-frequency components are treated with a shrinkage of 2D-DOST coefficients. The edges, for enhancement, are detected using a ratio-based edge detection algorithm. The proposed method is tested, verified, and compared with some well-known models on C-band and X-band SAR images. A detailed experimental analysis is illustrated.


Nanophotonics ◽  
2020 ◽  
Vol 9 (10) ◽  
pp. 3271-3278 ◽  
Author(s):  
Qian Ma ◽  
Qiao Ru Hong ◽  
Xin Xin Gao ◽  
Hong Bo Jing ◽  
Che Liu ◽  
...  

AbstractFor the intelligence of metamaterials, the -sensing mechanism and programmable reaction units are two important components for self-recognition and -determination. However, their realization still face great challenges. Here, we propose a smart sensing metasurface to achieve self-defined functions in the framework of digital coding metamaterials. A sensing unit that can simultaneously process the sensing channel and realize phase-programmable capability is designed by integrating radio frequency (RF) power detector and PIN diodes. Four sensing units distributed on the metasurface aperture can detect the microwave incidences in the x- and y-polarizations, while the other elements can modulate the reflected phase patterns under the control of a field programmable gate array (FPGA). To validate the performance, three schemes containing six coding patterns are presented and simulated, after which two of them are measured, showing good agreements with designs. We envision that this work may motivate studies on smart metamaterials with high-level recognition and manipulation.


2016 ◽  
Vol 26 (04) ◽  
pp. 1650016 ◽  
Author(s):  
Loukianos Spyrou ◽  
David Martín-Lopez ◽  
Antonio Valentín ◽  
Gonzalo Alarcón ◽  
Saeid Sanei

Interictal epileptiform discharges (IEDs) are transient neural electrical activities that occur in the brain of patients with epilepsy. A problem with the inspection of IEDs from the scalp electroencephalogram (sEEG) is that for a subset of epileptic patients, there are no visually discernible IEDs on the scalp, rendering the above procedures ineffective, both for detection purposes and algorithm evaluation. On the other hand, intracranially placed electrodes yield a much higher incidence of visible IEDs as compared to concurrent scalp electrodes. In this work, we utilize concurrent scalp and intracranial EEG (iEEG) from a group of temporal lobe epilepsy (TLE) patients with low number of scalp-visible IEDs. The aim is to determine whether by considering the timing information of the IEDs from iEEG, the resulting concurrent sEEG contains enough information for the IEDs to be reliably distinguished from non-IED segments. We develop an automatic detection algorithm which is tested in a leave-subject-out fashion, where each test subject’s detection algorithm is based on the other patients’ data. The algorithm obtained a [Formula: see text] accuracy in recognizing scalp IED from non-IED segments with [Formula: see text] accuracy when trained and tested on the same subject. Also, it was able to identify nonscalp-visible IED events for most patients with a low number of false positive detections. Our results represent a proof of concept that IED information for TLE patients is contained in scalp EEG even if they are not visually identifiable and also that between subject differences in the IED topology and shape are small enough such that a generic algorithm can be used.


2016 ◽  
Vol 34 (1) ◽  
pp. 54-76
Author(s):  
Sebastian Jäckle

This paper explores the determinants of ministerial duration within the German Länder between 1990 and 2010. In arguing that different terminal events ceasing ministerial tenures should be analyzed separately, it distinguishes four exit types: voluntary, forced, collective (ministers leaving office because their whole party does so) and exits that are neither volitional acts of the minister nor politically induced. Depending on the exit type, competing-risks Cox-models show different effects for one and the same variable on the hazard for ministerial turnover. Seniority in high-level politics for example helps not to be forced out of office while it has no effect on voluntary or collective exits. Heading an important ministry on the other hand increases the chances to rise to other positions in high politics or private business, but does not impact the other two hazards. The analysis furthermore shows that the principal-agent-logic known from Westminster systems with the prime minister being largely sovereign in hiring and firing cabinet members must be adapted to the German context of frequent coalition governments. In coalition governments, only ministers from the same party as the prime minister exhibit higher hazards for forced exits, while ministers from other coalition partners are much safer in that regard.


2013 ◽  
Vol 471 ◽  
pp. 59-63
Author(s):  
Mohd Noor Arib Rejab ◽  
Roslan Abd Rahman ◽  
Raja Ishak Raja Hamzah ◽  
Jawaid Iqbal Inayat Hussain ◽  
Nazirah Ahmad ◽  
...  

This paper presents an evaluation on elastomeric mount used to isolate vibration from powertrain to chassis or structure vehicle. The assessments started with measurement of noise inside compartment, and exhaust noise. This is followed by the measurement of vibration on both sides of elastomeric mounts. The noise in the compartment and exhaust noise is measured according to BS 6086: 1981 and BS ISO 5130: 2007. The noise in the compartment and vibration is tested in three conditions. Firstly, engine is run-up with load (driving at second gear); secondly, without load; and thirdly, without load but hanging. A microphone is fixed at the ear of the mannequin. The fast response and A weighting sound level meter were used for measurement noise in the compartment and exhaust noise. The vibration is measured in terms of acceleration on both sides of each elastomeric powertrain mounts. Two accelerometer transducers are fixed on both sides of powertrain elastomeric mounts. One side was identified as a source of vibration and the other as receiver of vibrations. The results showed that the pattern of overall vibration level on source and receiver increased from 1050 RPM (idling) to 4000 RPM on all test conditions. Vibration transmitted to chassis or receiver structure was analyzed using transmissibility concept. By evaluating test condition of engine run-up without load, informed that the front and rear mounts showed a high level transmissibility contributing to structure-borne noise.


2018 ◽  
Vol 71 (4) ◽  
pp. 238 ◽  
Author(s):  
Manoj K. Kesharwani ◽  
Amir Karton ◽  
Nitai Sylvetsky ◽  
Jan M. L. Martin

The S66 benchmark for non-covalent interactions has been re-evaluated using explicitly correlated methods with basis sets near the one-particle basis set limit. It is found that post-MP2 ‘high-level corrections’ are treated adequately well using a combination of CCSD(F12*) with (aug-)cc-pVTZ-F12 basis sets on the one hand, and (T) extrapolated from conventional CCSD(T)/heavy-aug-cc-pV{D,T}Z on the other hand. Implications for earlier benchmarks on the larger S66×8 problem set in particular, and for accurate calculations on non-covalent interactions in general, are discussed. At a slight cost in accuracy, (T) can be considerably accelerated by using sano-V{D,T}Z+ basis sets, whereas half-counterpoise CCSD(F12*)(T)/cc-pVDZ-F12 offers the best compromise between accuracy and computational cost.


Author(s):  
Umile Giuseppe Longo ◽  
Francesco Sofi ◽  
Vincenzo Candela ◽  
Laura Risi Ambrogioni ◽  
Giuditta Pagliai ◽  
...  

Abstract Background Our previous study on the 2016/2017 Serie A season showed that a greater likelihood of reaching the top positions in the Italian league “Serie A” seemed to be mainly related to sprint activity, goal attempts, total throws, target shots and assists. Therefore, we aim to evaluate the following season data in the same league to compare, confirm, and improve these results. Methods The data of all the matches played during the “Serie A” 2017–2018 season were obtained from the Italian soccer league. The teams’ analysis was performed in terms of total distance covered in km, jogging, running and sprint activities, average speed, and match statistics (total shots, shots on target, goal attempts, assists, turnovers, and steals). Results Teams that reached the first four positions revealed a lower percentage of running (65.98 ± 1.51 vs. 66.84 ± 2.18; p < 0.001), a higher percentage of jogging (25.61 ± 1.71 vs. 25.30 ± 1.97; p = 0.037) and sprint activities (8.41 ± 1.04 vs. 7.86 ± 0.82; p < 0.001). Match statistics seem to be statistically different between the first four teams the other teams. The total goals are strongly associated both with the total score at the end of the championship (R = 0.906; p < 0.001) and with the position in the final ranking (R = 0.850; p < 0.001). Conclusions Our results suggest that high-level teams have a lower running rate and a higher percentage of jogging and sprinting than other teams.


Information ◽  
2021 ◽  
Vol 12 (1) ◽  
pp. 19
Author(s):  
Alexey Semenkov ◽  
Dmitry Bragin ◽  
Yakov Usoltsev ◽  
Anton Konev ◽  
Evgeny Kostuchenko

Modern facial recognition algorithms make it possible to identify system users by their appearance with a high level of accuracy. In such cases, an image of the user’s face is converted to parameters that later are used in a recognition process. On the other hand, the obtained parameters can be used as data for pseudo-random number generators. However, the closeness of the sequence generated by such a generator to a truly random one is questionable. This paper proposes a system which is able to authenticate users by their face, and generate pseudo-random values based on the facial image that will later serve to generate an encryption key. The generator of a random value was tested with the NIST Statistical Test Suite. The subsystem of image recognition was also tested under various conditions of taking the image. The test results of the random value generator show a satisfactory level of randomness, i.e., an average of 0.47 random generation (NIST test), with 95% accuracy of the system as a whole.


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