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Peak detection is an important step in mass spectrometry as accurately identifying characteristic peaks is key to data analysis. In order to address the issue of false peak detection, while simultaneously ensuring accurate detection of weak and overlapped peaks, this paper introduces an improved algorithm for mass spectrometry integrating weighted continuous wavelet transform with particle swarm optimization-based Otsu (WWTPO). The algorithm applies the weighted continuous wavelet transform (WCWT) to compress the frequency spectrum signal into a smaller scale range, which allows for the acquisition of more distinct and informative peak information. Moreover, the algorithm employs the particle swarm optimization (PSO) algorithm to iteratively evaluate the optimal image segmentation threshold, which addresses the challenge of inaccurate Otsu image segmentation. The method was applied to detect simulated peaks as well as matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) datasets. The performance evaluation was conducted using receiver operating characteristic (ROC) curves, F1 measure and F-scores. Through comparison with continuous wavelet transform (CWT) and genetic algorithm-based threshold segmentation (WSTGA), multi-scale peak detection (MSPD) and CWT and image segmentation (CWT-IS), the results demonstrate that WWTPO exhibits excellent performance in peak detection. The determination of 4-isopropyltoluene also demonstrates that WWTPO has excellent practical application. This method not only maintains a low false peak identification rate but also detects more weak peaks and overlapping peaks, further improving the accuracy and efficiency of peak detection in mass spectrometry. [ABSTRACT FROM AUTHOR]

As a major energy source in China, the occupational health and well‐being (OHW) of miners is a priority. Various statistical techniques have been used to identify factors or assess OHW to provide valuable information for the implementation of health promotion activities. The main bottleneck is the limited focus on solutions that address the demands of both organizations and individuals, and scientific and effective decision‐making is pending. Therefore, this study describes the OHW mechanism covering both antecedents and consequences through the driving force‐pressure‐state‐impact‐response model. A probabilistic model of management tradeoff analysis was established by using a Bayesian decision network. Causal relationships and dependencies between multiple factors are captured visually. The model was verified and applied with samples of miners (N = 816). The results showed that the comprehensive strategy (R5) was the best tactic, and the management effect of stress (R2) and vulnerability (R3) was prominent. This study provides a valuable tool for managers to identify priority management factors. Prioritizing tactics formulated from dual demands of organizational and individual can ensure project feasibility, operability, and effectiveness. This study is a novel attempt to combine theory with practice, which is timely and necessary for management. [ABSTRACT FROM AUTHOR]

Despite the popularity of ion mobility spectrometry (IMS) for glycan analysis, its limited structural resolution hinders the effective separation of many glycan isomers. This leads to the overlap of IMS peaks, consequently impacting the accurate identification of glycan compositions. To this end, an improved algorithm, namely second-order differentiation combined with a simulated annealing particle swarm optimization algorithm based on sine adaptive weights (DWSA-PSO), was proposed for the separation of overlapping IMS peaks formed by glycan isomers. DWSA-PSO first performed second-order differentiation to automatically determine the number of components in overlapping peaks and exclude impossible single-peak combinations. It then introduced sinusoidal adaptive weights and a simulated annealing mechanism to improve the algorithm's search capability and global optimization performance, thereby enabling accurate and efficient separation of individual peaks. To evaluate the performance of DWSA-PSO and its application to the separation of glycan isomers, multiple sets of overlapping peaks with different degrees of overlap were simulated, and various types of multi-component overlapping peaks were formed using six disaccharide and four trisaccharide isomers. The experimental results consistently demonstrated that the DWSA-PSO algorithm outperformed both the improved particle swarm optimization (IPSO) algorithm and the dynamic inertia weight particle swarm optimization (DIWPSO) algorithm in terms of separation accuracy, running time, and fitness values. In addition, the DWSA-PSO algorithm was successfully applied to the separation of glycan isomers in malt milk beverage. All these results reveal the capability of the DWSA-PSO algorithm to facilitate the accurate identification of glycan isomers. [ABSTRACT FROM AUTHOR]

Within the Beibuwan Basin in the western part of the South China Sea, there are a large number of low -resistivity reservoirs in gravelly sandstones, with complex pore structure and fluid distribution, and the water saturation of the formation calculated by conventional methods is on the high side, which makes it difficult to distinguish between irreducible water, movable water and movable oil, and makes it difficult to discriminate between the fluid properties of the formation and to evaluate the oil saturation of the reservoir. In view of this, the cause of low resistivity in gravelly sandstone reservoirs was analyzed from internal and external factors based on core assay data such as mercuric pressure and thin section, and combined with logging and mud-logging characteristics. On the basis of the reservoir classification, the petroelectric parameters of the low-resistivity and high - resistivity reservoirs were finely etched to obtain the evaluation parameters applicable to different microporous structures. At the same time, the variable T2 cutoff value processing was performed based on the " morphology method" and in conjunction with nuclear magnetic resonance (NMR) logging. Compared with the traditional fixed T2 cutoff value, the obtained results can effectively evaluate the content of irreducible and movable fluids, which significantly improves the accuracy of formation fluid analysis and the compliance rate of logging interpretation of low-resistivity reservoirs, and then forms a set of comprehensive fluid identification and reservoir evaluation method for low-resistivity reservoirs with complex pore structure in gravelly sandstone. By applying this evaluation method, a large number of low-resistivity reservoirs were found in the old wells, which confirms that this method is highly practical and operable. This study is of great significance to the fluid identification and evaluation of the low-permeability and low-resistivity reservoirs with complex pore structures. [ABSTRACT FROM AUTHOR]