The accuracy of electromyographic differential diagnostics of essential tremor and Parkinson's disease in various patient postures was studied. To assess the accuracy of differential diagnostics, a mathematical me...
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ISBN:
(数字)9798331518752
ISBN:
(纸本)9798331518769
The accuracy of electromyographic differential diagnostics of essential tremor and Parkinson's disease in various patient postures was studied. To assess the accuracy of differential diagnostics, a mathematical method was developed on the basis of the analysis of wave trains of the electrical activity of antagonist muscles. To compare the accuracy of differential diagnostic methods, we used a computational experiment. Patients with the first stage of Parkinson's disease with a tremor in the left arm (14 subjects) and right arm (14 subjects), as well as patients with essential tremor (14 subjects), were studied. A relaxed posture and posture with arms extended forward were compared. The results of comparing the relaxed posture and the posture with outstretched arms demonstrated that differential diagnostics should be performed in the relaxed posture of the patient regardless of which side of the patient's body tremor is observed. If diagnostics in the relaxed posture is impossible due to the fact that the patient does not have resting tremor, it is advisable to use the posture with outstretched arms.
The main attractive feature of distributed video coding (DvC) is its use of low-complexity encoders, which are required by low-resource networked applications. Unfortunately, the performance of the currently proposed ...
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This dissertation addresses the problems of image denoising and compression. image denoising and compression are the fundamental problems in imageprocessing, and often use transform techniques. In this dissertation, ...
This dissertation addresses the problems of image denoising and compression. image denoising and compression are the fundamental problems in imageprocessing, and often use transform techniques. In this dissertation, the wavelet transform is used and new signalprocessing techniques are applied in the wavelet domain. The sparsity of the wavelet transform, i.e., a signal energy is concentrated on few large magnitude coefficients, is a main property exploited by wavelet based imageprocessingapplications. The new methods for image denoising problem introduced in this dissertation exploits the directional structure of the two-dimensional wavelet transform. For image compression, correlations between adjacent scales (levels) and coefficient pixels, i.e., inter and intra-correlation, are adaptively exploited in the proposed algorithm. The most frequently used technique in image denoising problems is a thresholding operation. Thresholding the wavelet coefficients exploits the sparse property of the wavelet transform. Applying thresholding to all coefficients uniformly, however, produces oversmoothing of edges and undersmoothing in uniform regions. Recently, adaptive wavelet thresholding utilizing spatial and adjacent scale correlations has been shown to yield good results. This dissertation introduces a related, but more direct, technique for adaptively processingwavelet coefficients based on partitioning of the coefficient space. In the wavelet domain, the coefficient space is partitioned through vector quantization and mask functions are used to obtain the denoised wavelet coefficients. This approach is better able to exploit structure in the coefficient domain and presented simulations show that the proposed technique yields superior performance compared with current wavelet denoising methods. A new embedded waveletimage compression method, using quad-partition-based wavelet domain image compression, is also proposed. The introduced method uses a quad-partition-base
25 years after the seminal work of Jean Morlet, the wavelet transform, multiresolution analysis, and other space frequency or space scale approaches are considered standard tools by researchers in imageprocessing, an...
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ISBN:
(纸本)9780819464514
25 years after the seminal work of Jean Morlet, the wavelet transform, multiresolution analysis, and other space frequency or space scale approaches are considered standard tools by researchers in imageprocessing, and many applications have been proposed that point out the interest of these techniques. This paper proposes a review of the recent published works dealing with industrial applications of wavelet and, more generally speaking, multiresolution analysis. More than 180 recent papers are presented.
Geological hazards in densely vegetated mountainous regions are challenging to detect due to terrain concealment and the limitations of traditional visualization methods. This study introduces the LiDAR image highligh...
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Geological hazards in densely vegetated mountainous regions are challenging to detect due to terrain concealment and the limitations of traditional visualization methods. This study introduces the LiDAR image highlighting algorithm (LIHA), a novel approach for enhancing micro-topographical features in digital elevation models (DEMs) derived from airborne LiDAR data. By analogizing terrain profiles to non-stationary spectral signals, LIHA applies locally estimated scatterplot smoothing (Loess smoothing), wavelet decomposition, and high-frequency component amplification to emphasize subtle features such as landslide boundaries, cracks, and gullies. The algorithm was validated using the Mengu landslide case study, where edge detection analysis revealed a 20-fold increase in identified micro-topographical features (from 1907 to 37,452) after enhancement. Quantitative evaluation demonstrated LIHA's effectiveness in improving both human interpretation and automated detection accuracy. The results highlight LIHA's potential to advance early geological hazard identification and mitigation, particularly when integrated with machine learning for future applications. This work bridges signalprocessing and geospatial analysis, offering a reproducible framework for high-precision terrain feature extraction in complex environments.
The problem of filtering periodic noise in digital images in an automatic mode has been addressed by scientists in many countries. Several alternative methods have been proposed. Currently, approaches to solving the p...
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ISBN:
(数字)9798331518752
ISBN:
(纸本)9798331518769
The problem of filtering periodic noise in digital images in an automatic mode has been addressed by scientists in many countries. Several alternative methods have been proposed. Currently, approaches to solving the problem of quasi-periodic noise filtering in automatic mode are actively being investigated. This type of noise is more common in real images. This paper briefly discusses the methods that best meet the criteria for quasi-periodic noise filtering quality and computational complexity requirements. Additionally, a formalized description of the iterative method proposed by the authors is provided, along with the results of experimental studies comparing the proposed method with other approaches.
Passive acoustic sensing has emerged as an effective method for measuring the biodiversity of bat species. Accurate, dependable and open-source technologies, which enable the classification and the detection of bat ca...
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Handwritten signature forgery detection is essential for authenticating signatures to address the risks of document falsification, identity theft, and financial fraud from signature forgeries. This study presents a re...
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ISBN:
(数字)9798331518752
ISBN:
(纸本)9798331518769
Handwritten signature forgery detection is essential for authenticating signatures to address the risks of document falsification, identity theft, and financial fraud from signature forgeries. This study presents a reliable approach to accurately classify genuine and forged signatures using deep learning and image pre-processing techniques. Specifically, the proposed method utilizes Inceptionv4 with Sobel edge detection. Inceptionv4, a deep convolutional neural network, is used to extract features from signature images, while Sobel edge detection enhances these features. By applying Sobel edge detection during the image pre-processing stage, we emphasize the edges of the signatures, which aids in the classification process. Furthermore, we implemented data augmentation techniques to effectively generate additional datasets, overcoming the significant limitations of the lack of custom signature datasets. By integrating Inception v4’s capabilities and Sobel edge detection, the model achieved a high accuracy of 96.19% and an F1-score of 96.18%. These results demonstrate the potential and effectiveness of the proposed approach in detecting signature forgeries.
Low-frequency oscillations in the human circulatory system is important for basic physiology and practical applications in clinical medicine. Our objective was to study which mechanism (central or local) is responsibl...
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Low-frequency oscillations in the human circulatory system is important for basic physiology and practical applications in clinical medicine. Our objective was to study which mechanism (central or local) is responsible for changes in blood flow fluctuations at around 0.1 Hz. We used the method of imaging photoplethysmography synchronized with electrocardiography to measure blood-flow response to local forearm heating of 18 healthy male volunteers. The dynamics of peripheral perfusion was revealed by a correlation processing of photoplethysmography data, and the central hemodynamics was assessed from the electrocardiogram. wavelet analysis was used to estimate the dynamics of spectral components. Our results show that skin heating leads to multiple increase in local perfusion accompanied by drop in blood flow oscillations at 0.1 Hz, whereas no changes in heart rate variability was observed. After switching off the heating, perfusion remains at the high level, regardless decrease in skin temperature. The 0.1 Hz oscillations are smoothly recovered to the base level. In conclusion, we confirm the local nature of fluctuations in peripheral blood flow in the frequency band of about 0.1 Hz. A significant, but time-delayed, recovery of fluctuation energy in this frequency range after cessation of the skin warming was discovered. This study reveals a novel factor involved in the regulation microcirculatory vascular tone. A comprehensive study of hemodynamics using the new technique of imaging photoplethysmography synchronized with electrocardiography is a prerequisite for development of a valuable diagnostic tool.
Implicit reward mechanism of Direct Preference Optimization (DPO) has facilitated its recent applications beyond large language models (LLMs), notably in aligning text-to-image models with human preferences. While pro...
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ISBN:
(数字)9798350368741
ISBN:
(纸本)9798350368758
Implicit reward mechanism of Direct Preference Optimization (DPO) has facilitated its recent applications beyond large language models (LLMs), notably in aligning text-to-image models with human preferences. While promising results have been achieved with algorithms such as Diffusion-DPO, their reliance on the assumptions of the Bradley-Terry model could potentially lead to significant overfitting. In this paper, we propose the Step Identical Preference Alignment (SIPA) method, departing text-to-image alignment from the assumptions of Bradley-Terry preference model. We assess the performance of four models, Diffusion-DPO, SPO, and SIPA, alongside the original model, on the HPS-v2 test set, which focus on three key aspects: text-image alignment, human value alignment, and generation diversity. Experimental results show that SIPA matches or outperforms existing SOTA alignment methods, and even exceeds the original model in terms of generation diversity, which compellingly demonstrates SIPA’s superiority in mitigating alignment overfitting.
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