Data Embedding in MPEG-1/Audio Layer II Compressed Domain using Side Information

An apparatus for the transmission of speech signals reduces the effect of disturbances on the transmission quality. Two microphones are provided for picking up speech signals. Signal processing ensues in three partial frequency bands. The microphone signals are high-pass filtered in a lower frequency band, in the middle frequency band the signal is weighted with a scalar factor, so that this frequency band is damped during the speech pauses, and in the upper frequency band, an adaptive filter is used. At the beginning of the processing, a treble enhancement of the signals ensues, which is canceled by an inverse filter before the output of the improved signal.

In spreading spectrum audio watermarking system, the random noise on full-frequency is very common, which greatly affects the receiving efficiency. In this paper, we proposed an optimized receiving method, which is specially used to resist full-frequency domain random noise. For most audio signals, especially voice signals, the energy is mainly concentrated in the middle and low frequency bands, and the energy in high frequency band is less. We take advantage of this feature to optimize the performance of spreading spectrum audio watermarking system. Experimental results show that our optimized receiving method will ultimately improve the decoding performance.

Single Watermark Embedding (SWE) technique has been proposed in the [9] by Wong et al. SWE is used to embed a watermark bit sequence into digital images using two secret keys. Another technique used Discrete Cosine Transform (DCT) which enables an 8 × 8 block of an image to be separated into three frequency bands namely the high, middle and low frequency bands. These frequency bands are considered to embed watermark into. It is better to embed watermark in some coefficients in the middle frequency band due to its insensible visibility. In this paper, an improved single watermark embedding (ISWE) is proposed to create a more powerful watermarking scheme that can give better watermarked image quality and enhance watermark’s robustness against JPEG compression attack.

일반적인 워터마킹 기술들은 영상의 특성을 고려하지 않은 채 신체 책인 영상에 워터마크를 삽입하는 경우가 많다 본 논문에서는 워터마킹 알고리즘을 웨이브렛을 기반으로 구현을 하였으며, 견고한 워터마크 삽입을 위해 Multi-Threshold Watermark Coding(MTWC)의 원리에 기초하여 Region of Interest(ROI)라고 불리우는 영상의 영역에 큰 계수를 찾아 워터마크를 삽입하게 된다. 이때 Human Visual System(HVS)을 이용하여 견고성과 비가시성의 향상을 도모하였다. 워터마크 삽입대역은 중주파 대역에 삽입을 하게 되는데 중주파 대역에 삽입한 워터마크는 어떠한 영상 처리과정 후에도 높은 비율의 추출을 보였으며, 워터마크가 삽입된 영상의 왜곡정도도 다른 대역보다 상대적으로 적게 나타나므로 중주파 대역에 워터마크를 삽입하였다. 워터마크는 의사 랜덤 시퀀스(Pseudo Random Sequence)로 구성되어 있고 워터마크의 검출은 Cox의 유사도 측정식을 이용하여 워터마크의 삽입여부를 판단한다 General watermarking techniques tend not to consider intrinsic characteristics of image, so that watermarks are embeded to entire images. In this paper, we present a watermarking algorithm based on wavelet domain, and the watermark is embedded into large coefficients in region of interest(ROI) being based on principle of multi-threshold watermark coding(MTWC) for robust watermark insertion. We try to accomplish both image duality and robustness using human visual system(HVS). The watermarks are embedded in middle frequency bands because the distortion degree of watermarked images appears to be less than lower frequency bands, and the embedded watermarks in the middle bands showed high extraction ratios after some distortion. The watermarks are consisted of pseudo random sequences and detected using Cox's similarity mesurement.

The driving motor system of hybrid electric vehicle is under complex vibration conditions, and is subject to the common operating conditions of vehicle and engine. there are some differences between GB/T 18488-2015 and ISO 19453.3:2018 in requirements of working conditions. In this paper, a typical hybrid electrical vehicle (HEV) is used to collect the driving motor vibration condition. The test results show that the vibration energy of the drive motor system of HEV is the most intense in the low frequency band (10Hz $\sim 30$ Hz). It gradually weakens in the middle frequency band (30Hz $\sim 1000$ Hz) and tends to be stable in the high frequency band (1000Hz $\sim 2000$ Hz). However, the vibration intensity at the end of the high frequency band has an increasing trend, which is not reflected in the standards. There may be some deficiency in the vibration resistance assessment of the drive motor system at the high frequency operating point. The determination of vibration energy value is directly related to the acceleration time and acceleration life of the working condition. Compared with other test site specifications, this paper analyzes the reasons why the RMS of the test results is weaker than the standard values. It is proved through the test that the determination of vibration condition needs to determine the reasonable acceleration time of working condition according to the design life of the product, so as to determine the intensity of vibration condition.

This paper presented one novel microstrip antenna with triple-band triple-mode and triple-polarization (TBTMTP) characteristics. In the lower frequency band, the antenna operates in the linearly polarized (LP) dipole mode with omnidirectional radiation pattern along the YOZ plane which is like one horizontally located dipole antenna. In the middle frequency band, the antenna operates in the LP dipole mode with omnidirectional radiation pattern along the XOY plane which is like one vertically located dipole antenna. While in the upper frequency band, the antenna works in the circularly polarized (CP) patch mode with directional radiation patterns along the Z-axis direction. Three modes with different patterns were excited in three different bands because of the mutual-coupling periodical circular patches and inductance metal pins. By etching inverted L shaped slot in the down circular mental patch, CP is realized for the patch mode without affecting the other two modes. The surface current distribution is introduced to analyze the antenna working principle. Due to the compact structure, easy fabrication, radiation pattern selectivity and polarized diversity, this antenna has potential application value in wireless communications in future.

Power spectral analysis of fetal heart rate variability has been proposed to provide a non-invasive estimate of autonomic balance. However, there are few systematic data before birth. We therefore examined developmental changes in the frequency power spectrum at very low (0-0.04 Hz), low (0.04-0.15 Hz) and high frequencies (0.15-0.4 Hz), as well as the ratio of low- to high-frequency power (LF/HF), in chronically catheterized, healthy fetal sheep at 0.6 (n = 8), 0.7 (n = 7) and 0.8 gestational age (ga; n = 11). In a second study, 0.8 ga fetuses received either atropine (4.8 mg bolus, then 4.8 mg h(-1) for 30 min, n = 6) or 6-hydroxydopamine (20 mg ml(-1) at 2.5 ml h(-1) for 3 h; n = 9). Data were analysed by sleep state, defined by low-voltage-high-frequency (LV) or high-voltage-low-frequency (HV) EEG. Total spectral power increased with gestational age (P < 0.05), while LF/HF decreased from 0.6 to 0.7 ga. At 0.8 ga, heart rate and LF/HF were significantly higher during HV than LV sleep (P < 0.05). Consistent with this, although total spectral power was not significantly greater during HV sleep, there was a significant interaction between sleep state and frequency band (P = 0.02). Both atropine (P = 0.05) and 6-hydroxydopamine (P < 0.05) were associated with an overall reduction in spectral power but no significant effect on the LF/HF ratio. This study does not support substantial, consistent differences between the frequencies of sympathetic and parasympathetic activity in late-gestation fetal sheep.

Feature extraction is one of the key links of helicopter fault diagnosis. Wavelet analysis is a new time-frequency analysis method. Wavelet packet analysis is a more precise orthogonal decomposition method based on wavelet analysis. It makes multi-level frequency band division for signals in the whole frequency band. In this paper, based on wavelet packet analysis, the signal with fault information is decomposed into different frequency bands, then the signal in each frequency band is analyzed statistically, and the energy value of the frequency band containing the fault information of the component to be diagnosed is formed as the characteristic index for fault diagnosis. Simulation results show the effectiveness of this method.

To characterize levator ani muscle (LAM) activity in nulligravidas using magnetomyography (MMG) and define MMG characteristics associated with LAM activity with and without accessory muscle contributions. MMG data were collected from eight nulligravidas during rest and voluntary LAM contractions (Kegels) of varying intensity. We utilized simultaneous vaginal manometry and surface electromyography (sEMG) to evaluate for accessory muscle recruitment. Moderate Kegel (MK) MMG trials were sub-selected based on the presence or absence of accessory muscle interaction. Amplitude and spectral-related indicators were calculated across MK epochs: root-mean square (RMS) amplitude, percentage amplitude relative to rest, and relative power spectrum density (rPSD) in three frequency bands (low, middle, high). Ternary diagram characterized rPSD from selected Kegels and ROC analysis was performed to identify cut-points to differentiate MKs from interacting MKs. Nineteen MMG recordings were obtained. Amplitude and spectral parameters were significantly different between isolated and interacting MK epochs. Mean RMS and power values of the isolated MK were, respectively, 120.66 ± 43.8 fT and 1.72 ± 1.44 (T2 /Hz)*10-28 . Amplitudes of MK were 64% and 117 higher than baseline activities for the isolated and interacting epochs, respectively. ROC curves reveled cut-off points on low and middle frequency bands that achieved perfect separation (ROC-AUC = 1.0) between isolated and interacting MK. Our study demonstrates that MMG, a novel biomagnetic technique, allows precise detection and characterization of normal female pelvic floor function. Results show that isolated moderate voluntary contraction of the LAMs produces distinct MMG amplitude and spectral characteristics compared with Kegels involving co-activation of other muscle groups.

Evidence is presented for local and remote wind‐forcing of deep ocean currents in three frequency bands (corresponding to 3.7–8 day, 8–22 day, and 23–82 day periods) at a two‐year mooring in the eastern North Atlantic. Coherence between current meter velocities and estimated wind stress curl is largest for the deepest instrument (3000 m) and decreases toward the surface. The strongest evidence is found at 3000 m depth in the high frequency (3.7–8 day) band, where both components of velocity are significantly coherent with wind stress curl. Meridional velocity at 3000 m is also significantly coherent with wind stress curl in the low frequency (23–82 day) band, while zonal velocity in the low frequency band and both velocity components in the intermediate frequency (8–22 day) band are only marginally coherent. The results are compared with a stochastically‐forced linear quasi‐geostrophic model that includes a simple representation of the mid‐Atlantic Ridge. Good agreement between predicted and observed coherences is found for the 3000 m currents in the high frequency band, but only partial agreement is found between predicted and observed coherences in the low frequency band, and little agreement in the intermediate band. Kinetic energy levels at 3000 m are well predicted in all three bands. For the shallower instruments (1100 m and 500 m), observed coherences are at most marginally significant and energy levels are considerably higher than the theory predicts. Including an upper‐layer mean flow in the model improves the prediction of energy levels at the shallower instruments.

Times Varying Spectral Coherence Investigation of Cardiovascular Signals Based on Energy Concentration in Healthy Young and Elderly Subjects by the Adaptive Continuous Morlet Wavelet Transform

Deep neural networks with convolutional layers usually process the entire spectrogram of an audio signal with the same time-frequency resolutions, number of filters, and dimensionality reduction scale. According to the constant-Q transform, good features can be extracted from audio signals if the low frequency bands are processed with high frequency resolution filters and the high frequency bands with high time resolution filters. In the spectrogram of a mixture of singing voices and music signals, there is usually more information about the voice in the low frequency bands than the high frequency bands. These raise the need for processing each part of the spectrogram differently. In this paper, we propose a multi-band multi-resolution fully convolutional neural network (MBR-FCN) for singing voice separation. The MBR-FCN processes the frequency bands that have more information about the target signals with more filters and smaller dimensionality reduction scale than the bands with less information. Furthermore, the MBR-FCN processes the low frequency bands with high frequency resolution filters and the high frequency bands with high time resolution filters. Our experimental results show that the proposed MBR-FCN with very few parameters achieves better singing voice separation performance than other deep neural networks.

FV 5 Striato-pallidal connectivity in oscillatory activity of patients with dystonia

The vibration signal of transformer body contains abundant fault information. Extracting the effective characteristic parameters from the vibration signal can be used as an important basis for transformer fault diagnosis, which is the main method for non-intrusive monitoring of transformer faults at present. According to the vibration generation and transmission mechanism of transformer noumenon, this paper uses piezoelectric sensors, signal conditioning modules, high-speed data acquisition card and computer set up the transformer vibration monitoring system, and takes graphical language LabVIEW as the system software development platform. Wavelet packet-energy spectrum analysis method is used to analyze the vibration signal on the surface of transformer oil tank in time domain and frequency domain, quantifying the energy distribution of vibration signal in different frequency bands, and taking the percentage of each frequency band energy in the total energy as the characteristic parameter to monitor and diagnose the operation status of transformer. Field test results show that there is a significant difference in the energy distribution of the vibration signals before and after the transformer failure. This method can effectively extract the characteristics of the vibration signal in different states and obtain the percentage of energy distribution of the vibration signal in each frequency band, which can be used as the basis for transformer fault diagnosis.

A compact four-element dual-band multiple-input and multiple-output (MIMO) antenna system is proposed to achieve high isolation and low channel capacity loss. The MIMO antenna was designed and optimized to cover the dual-frequency bands; the first frequency band is a wide band, and it covers the frequency range of 1550–2650 MHz, while the other frequency band covers the 3350–3650 MHz range. The measured wide-band impedance bandwidths of 1.1 GHz and 300 MHz were achieved in the lower and upper frequency bands, respectively. The proposed structure consists of four novel antenna elements, along with a plus-sign-shaped ground structure on an FR4 substrate. The overall electrical size of the whole dual-band MIMO antenna system is (W) × (L) × (H) for the lower frequency band. It achieved greater than 10 and 19 dB isolation in the lower and upper frequency bands, respectively. The antenna system accomplished an envelope correlation coefficient of in the lower frequency band, while it achieved in the higher frequency band. The computed channel capacity loss remained less than almost 0.4 bits/s/Hz in both frequency bands. Therefore, it achieved good performance in both frequency bands, with the additional advantage of a compact size. The proposed MIMO antenna is suitable for compact handheld devices and smartphones used for GSM (Global System for Mobiles), UMTS (Universal Mobile Telecommunications Service), WCDMA (Wideband Code Division Multiple Access), LTE (Long Term Evolution), 5G sub-6 GHz, PCS (Personal Communications Service), and WLAN (wireless local area network) applications.