Archaeological GPR data from antennas of different frequencies allow the identification of buried cultural heritage at different scales. Therefore, multi-frequency GPR systems are recommended for ...complicated subsurface archaeological conditions. GPR data fusion approaches, automatically or semi-automatically, can integrate data measurements from different frequency antennas, combine them into a single representation, and partially overcome the unavoidable trade-off between penetration and resolution. We propose an adaptively weighted fusion method for multi-frequency GPR data based on genetic algorithms (GAs). In order to evaluate the feasibility and the effectiveness of the strategy for archaeological prospection, we tested the procedure on GPR datasets acquired in two totally different archaeological conditions: rammed layers of an ancient wall, in Henan Province, China, and complex and elusive prehistoric archaeological features within a natural stratigraphic sequence on the volcanic Stromboli Island, Italy. The results demonstrate that the proposed strategy can maximize the information content of GPR profiles, enhancing the GPR interpretation possibilities in an automatic and objective way for different targets and in different subsurface conditions.
Ground-penetrating radar (GPR) technology plays an important role in near-surface geophysical surveys. Usually, the dataset acquired by a higher frequency antenna has higher resolution but limited ...penetration depth, while the dataset collected by a lower one has deeper penetration depth but lower resolution. It is necessary to fuse several different frequency datasets into a composite displayed profile to get a tradeoff between penetration depth and resolution. In such a case, we propose a novel multifrequency GPR data fusion method and test it on the data acquired from a limestone quarry in the Taihang Mountains of China. In our algorithm, time-varying weighting factors are calculated by the virtues of a sliding time window, i.e., designed with segmented signals. According to this approach, we can achieve better local characteristics of the signal and the smoothness of the signal waveform. The results show that the spectrum bandwidth of the fused signal is broadened, and the fusion profile significantly improves the imaging of internal structures for limestone on different scales.
•We implement a multi-frequency and multi-attribute GPR data fusion approach based on wavelet transform.•Our method is utilizing a dynamic fusion weight scheme derived from edge detection ...algorithm.•Information entropy and spatial frequency are developed as quantitative evaluation parameters to analyze the fusion outcomes.•We can obtain the advantage of penetration and resolution for the GPR characterization of subsurface.•The results demonstrate that the method can enhance the efficiency and accuracy of GPR data interpretation.
High frequency GPR signals offer high resolution while low frequency GPR signals offer greater depth of penetration. Effective fusion of multiple frequencies can combine the advantages of both. In addition, GPR attribute analysis can improve subsurface imaging, but a single attribute can only partly highlight details of different physical and geometrical properties of subsurface potential targets. In order to overcome these challenges, we implement an advanced multi-frequency and multi-attribute GPR data fusion approach based on 2-D wavelet transform utilizing a dynamic fusion weight scheme derived from edge detection algorithm, which is tested on data from a small glacier in the north-eastern Alps by 250 & 500 MHz central frequency antennas. Besides, information entropy and spatial frequency are developed as quantitative evaluation parameters to analyze the fusion outcomes. The results demonstrate that the proposed approach can enhance the efficiency and scope of GPR data interpretation in an automatic and objective way.
•Mulberry polyphenols promote the unfolding and aggregation of myofibrillar protein structure.•Mulberry polyphenols facilitate the transformation from α-helix to β-turn structure of myofibrillar ...protein.•Mulberry polyphenols help ameliorate the degradation of myofibrillar protein gel properties due to oxidation.•Protein aggregation caused by excessive addition of polyphenols deteriorates the gel properties of proteins.
In order to explore the mechanism of mulberry polyphenols inhibiting the oxidation of myofibrillar protein (MP), the effect of mulberry polyphenols on the structure and physicochemical properties of MP in the oxidation system was investigated. The results revealed that the content of carbonyl group and sulfhydryl group of MP was notably reduced, while the Zeta potential, storage modulus G' and surface hydrophobicity were improved when the addition of mulberry polyphenol was 0.5%. SDS-PAGE showed an irreducible aggregation of mulberry polyphenols with proteins. Fluorescence spectroscopy and FT-IR analysis manifested that mulberry polyphenols promoted the unfolding of protein structure and the transformation of α-helix to β-turn structure. Scanning electron microscopy (SEM) observed that oxidation with polyphenols facilitated the cross-linking and aggregation of MP more tightly. Nevertheless, excessive addition (≥1.0%) weakened its gel properties. Thus, to maintain the good quality of meat products, both polyphenols addition and oxidation intensity should be controlled simultaneously.
Structural damage identification technology based on modal parameters is an extremely effective monitoring method. Because of the structural characteristics of the conductor, with its small diameter ...and long span, it is not easy to obtain the modal parameters by manual excitation. Here, a method for structural health monitoring of the conductor under wind load excitation is proposed. Firstly, the natural frequency change law of the conductor after broken strand damage is obtained by analyzing the conductor modal parameters calculation formula and IEEE standards. Then, the vibration characteristics are calculated by vibration experiments and finite element methods. Finally, through the broken strand experiment, this paper demonstrates how to determine the damage degree of the conductor using the modal parameters. And it is applied to online monitoring in the field. The results show that this method is convenient, fast, and accurate.
Based on structural health monitoring technology, a new idea of identifying damage using modal analysis technique for transmission line conduct is proposed. Established a method to express the degree of damage by modal parameters. Through the broken strand experiment, further explained the phenomenon of natural frequency decrease after strand breakage, demonstrated the feasibility of using the variation of the natural frequency as a key parameter for the identification. Applied to the online monitoring of power equipment, explained the vibration characteristics of the breeze vibration, and listed the modal parameters of the conductors installed in the field.
The effects of mulberry fruit powder on the antioxidant capacity and gel properties of hammered minced beef, including oxidation degree, texture properties, rheological properties and protein ...structure, were investigated. The results manifested that the total antioxidant capacity (T-AOC) and DPPH free radical scavenging rate of minced beef were remarkably enhanced (P < 0.05) when the addition of mulberry fruit powder was 0.6%, while the contents of carbonyl and total sulfhydryl groups were reduced. Higher storage modulus (G′) and lower tanδ demonstrated that mulberry fruit powder conduced to the formation of a denser gel network structure and improved rheological properties. Furthermore, the improvement of hardness and resilience as well as the reduction of cooking loss rate suggested that mulberry fruit powder had a positive effect on maintaining the gel textural properties. Surface hydrophobicity and FT-IR analysis elucidated that mulberry fruit powder promoted the unfolding of protein structure and the transformation from α-helix to β-sheet structure. Nevertheless, a high concentration of mulberry fruit powder (≥1.0%) could jeopardize the structural properties and quality of minced meat gels. Thus, to maintain the good quality of meat products, both the addition of mulberry fruit powder and the oxidation degree should be controlled simultaneously.
•Mulberry fruit powder possesses antioxidant protection for hammered minced beef.•Mulberry fruit powder effectively prolongs the shelf life of minced beef.•Mulberry powder enhances the three-dimensional network structure of the gel.•Excessive mulberry powder deteriorates the stable conformation of the protein.
Located at the center of the Eurasian continent and accommodating as much as 44% of the present crustal shortening between India and Siberia, the Tianshan orogenic belt (TOB) is one of the youngest ...(<20 Ma) and highest (elevation>7000 m) orogenic belts in the world. It provides a natural laboratory for examining the processes of intracontinental deformation. In recent years, wide angle seismic reflection/refraction profiling and magnetotelluric sounding surveys have been carried out along a geoscience transect which extends northeastward from Xayar at the northern margin of the Tarim basin (TB), through the Tianshan orogenic belt and the Junggar basin (JB), to Burjing at the southern piedmont of the Altay Mountain. We have also obtained the 2D density structure of the crust and upper mantle of this area by using the Bouguer anomaly data of Northwestern Xinjiang. With these surveys, we attempt to image the 2D velocity and the 2D electric structure of the crust and upper mantle beneath the Tianshan orogenic belt and the Junggar basin. In order to obtain the small-scale structure of the crust–mantle transitional zone of the study area, the wavelet transform method is applied to the seismic wide angle reflection/refraction data. Combining our survey results with heat flow and other geological data, we propose a model that interprets the deep processes beneath the Tianshan orogenic belt and the Junggar basin.
Located between the Tarim basin and the Junggar basin, the Tianshan orogenic belt is a block with relatively low velocity, low density, and partially high resistivity. It is tectonically a shortening zone under lateral compression. A detachment exists in the upper crust at the northern margin of the Tarim basin. Its lower part of the upper crust intruded into the lower part of the upper and the middle crust of the Tianshan, near the Korla fault; its middle crust intruded into the lower crust of the Tianshan; and its lower crust and lithospheric mantle subducted into the upper mantle of the Tianshan. In these processes, the mass of the lower crust of the Tarim basin was carried down to the upper mantle beneath the Tianshan, forming a ∼20-km-thick complex crust–mantle transitional zone composed of seven thin layers with a lower than average velocity. The thrusting and folding of the sedimentary cover, the intrusive layer in the upper and middle crust, and the mass added by the subduction of the Tarim basin into the upper mantle of the Tianshan are probably responsible for the crustal thickening of the Tianshan. Due to the important mass deficiency in the crust and the upper mantle of the Tianshan, buoyancy must occur and lead to rapid ascent of the Tianshan.
The episodic tectonic uplift of the Tianshan and tectonic subsidence of the Junggar basin are closely related to the evolution of the Paleozoic, Mesozoic, and Cenozoic Tethys.
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