Tourism image classification plays an important role in the study of clarifying the real perception of tourism resources by tourists, which cannot be studied in depth by human vision alone. The ...development of convolutional neural networks in computer vision brings new opportunities for tourism image classification research. In this study, SqueezeNet, a lightweight convolutional neural network, was selected and improved on the basis of the original model for 3740 Slender West Lake tourism image datasets. It is found that the validation accuracy of the model is up to 85.75%, and the size is only 2.64 MB, which is a good classification effect. This reduces the parameters while ensuring high accuracy classification of tourism images, providing a more scientific reference for the study of tourism images and pointing out a new direction for the development and planning of tourism resources.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The inverse spinel ferrimagnetic NiCo2O4 presents a unique model system for studying the competing effects of crystalline fields, magnetic exchange, and various types of chemical and lattice disorder ...on the electronic and magnetic states. Here, magnetotransport anomalies in high‐quality epitaxial NiCo2O4 thin films resulting from the complex energy landscape are reported. A strong out‐of‐plane magnetic anisotropy, linear magnetoresistance, and robust anomalous Hall effect above 300 K are observed in 5–30 unit cell NiCo2O4 films. The anomalous Hall resistance exhibits a nonmonotonic temperature dependence that peaks around room temperature, and reverses its sign at low temperature in films thinner than 20 unit cells. The scaling relation between the anomalous Hall conductivity and longitudinal conductivity reveals the intricate interplay between the spin‐dependent impurity scattering, band intrinsic Berry phase effect, and electron correlation. This study provides important insights into the functional design of NiCo2O4 for developing spinel‐based spintronic applications.
Strong perpendicular magnetic anisotropy, intrinsic linear magnetoresistance, and robust anomalous Hall effect above 300 K are realized in ultrathin NiCo2O4 films. The anomalous Hall resistance peaks at around room temperature, and reverses its sign at low temperature in thinner films, reflecting the intricate interplay between the spin‐dependent impurity scattering, band intrinsic Berry curvature, and electron correlation effect.
Mid-Ocean Ridge Basalts (MORBs) from the South China Sea (SCS) have attracted great attention from geologists in the past decade, but their petrogenesis still remains controversial. Here, we show ...that the Mg isotopes of MORBs from Integrated Ocean Drilling Program (IODP) Sites U1431, U1433 and U1434 are heterogeneous and present the mechanisms causing such heterogeneity. The MORBs from Sites U1431, U1433 and U1434 have δ26Mg values ranging from −0.35‰ to −0.21‰, from −0.34‰ to −0.13‰, and from −0.30‰ to −0.20‰, respectively. Together with all the published data, we found the MORBs at Site U1431 with high MgO contents (> 9 wt%) usually have δ26Mg values that are generally lower than the normal mantle (−0.25‰ ± 0.04‰), whereas some of the Site U1433 MORBs are higher than the normal mantle. Shallow-level geological processes like seawater alteration have negligible effects on the Mg isotope fractionation of our samples. Elemental ratio indicative of the degree of partial melting (like Sm/Nd) from the same site also shows no relationship with the δ26Mg variations. Olivine is proposed to have light Mg isotopes. Considering the high MgO (> 9 wt%) contents of low-δ26Mg samples and the petrographic evidence, we propose that their slightly light Mg isotopic compositions of U1431 MORBs may result from the enrichment of olivine, rather than reflecting the mantle source. Moreover, low Ce/Pb ratios and most variable δ26Mg values of some U1433 MORBs suggest that lower continental crustal materials have contributed to their source. As all the previously published MORBs are evolved, we use the Revpet to estimate the mantle melting conditions of SCS MORBs, including the Site U1500 samples recovered from the northern margin of SCS. Compared with the global MORBs data, there is no thermal anomaly in SCS MORBs. Together with our new Mg isotope data, therefore, we propose that the role of the Hainan mantle plume in the opening and spreading of the SCS may be insignificant.
•The Mg isotope variation of U1431 MORBs from the South China Sea is caused by the enrichment of olivine.•Lower continental crust contamination may account for the high δ26Mg values of U1433 MORBs.•No thermal evidence of Hainan mantle plume can be found during the seafloor spreading of SCS.
In order to better understand the thermal comfort of urban parks and provide empirical reference for urban green space optimization design, 5 days’ field monitoring was conducted in People’s Park in ...Urumqi, an oasis city in an arid region of China. Combined with GIS spatial interpolation, correlation analysis, and regression analysis, the spatial and temporal distribution of thermal comfort (HI and WBGT) of urban parks was discussed. The results showed the following. (1) The thermal comfort in the morning was generally higher than that in the afternoon, and the thermal comfort near the water body and lush vegetation in the park was higher, while the thermal comfort on the road was lower, especially on Hotan Street and Binhenan Road, which were far away from the park. Therefore, it is recommended that nearby residents exercise outdoors in the morning as much as possible and in the park, and in the afternoon, keep to the park and its vicinity and try to sit quietly or walk slowly, avoiding the less comfortable areas, such as Hotan Road and Binhenan Road. (2) Due to dense vegetation and lack of infrastructure construction, the thermal comfort area does not have the conditions for crowd gathering. Therefore, it is recommended that the park improve the infrastructure of relevant areas. (3) Through the analysis of the significant influence of explanatory variables on the explained variables, it shows that the ventilation effect in the park is insufficient. Therefore, it is recommended to appropriately increase the number of trees, water bodies, and wind channels to promote ventilation in the park so as to improve the thermal comfort of the park. These findings provide a theoretical basis and technical reference for optimizing the thermal comfort of urban green space and establishing a healthier and more comfortable living environment for urban residents.
The superior size and power scaling potential of ferroelectric-gated Mott transistors makes them promising building blocks for developing energy-efficient memory and logic applications in the ...post-Moore's Law era. The close to metallic carrier density in the Mott channel, however, imposes the bottleneck for achieving substantial field effect modulation via a solid-state gate. Previous studies have focused on optimizing the thickness, charge mobility, and carrier density of single-layer correlated channels, which have only led to moderate resistance switching at room temperature. Here, we report a record high nonvolatile resistance switching ratio of 38,440% at 300 K in a prototype Mott transistor consisting of a ferroelectric PbZr
Ti
O
gate and an RNiO
(R: rare earth)/La
Sr
MnO
composite channel. The ultrathin La
Sr
MnO
buffer layer not only tailors the carrier density profile in RNiO
through interfacial charge transfer, as corroborated by first-principles calculations, but also provides an extended screening layer that reduces the depolarization effect in the ferroelectric gate. Our study points to an effective material strategy for the functional design of complex oxide heterointerfaces that harnesses the competing roles of charge in field effect screening and ferroelectric depolarization effects.
Harmful algal blooms (HABs) caused by Heterosigma akashiwo are occurring in coastal waters frequently, posing a great risk to marine environments and subsequent treatment processes like desalination. ...UV-assisted permanganate oxidation (UV/KMnO4) is recognized as an innovative advanced oxidation process. This study investigated the inactivation and removal efficiencies of H. akashiwo cells by UV/KMnO4. Algal cells were effectively disintegrated into fragments by UV/KMnO4. Also, the degradation of photosynthetic pigments, membrane lipid peroxidation, and severe oxidative stress in algal cells was observed. The removal efficiency of algal cells reached 80.2% by 20 min of UV/KMnO4 oxidation, with a KMnO4 dosage of 5 mg L−1. In addition, the residual algal cells could be completely removed by a subsequent self-settling process, without an additional coagulation procedure. The fragmentation of algal cells caused by UV/KMnO4 may facilitate the formation of algal flocs, thereby improving the cell settleability. Furthermore, UV254 was significantly reduced by UV/KMnO4, which is expected to reduce the formation of disinfection byproducts and membrane fouling. This study elucidates that UV/KMnO4 can be a promising technique for the efficient treatment of harmful marine algae.
A mooring with two sediment traps and a current meter was deployed for 315 days near the Wocan hydrothermal field (∼650 m from the vent) on the Carlsberg Ridge to study the vertical and temporal ...variations in the composition and flux of the settling particles dispersed by the hydrothermal plume. The collected settling particles were characterized by a high content of hydrothermally derived minerals, including Cu-Fe-Zn sulfides, sulfates, native sulfur, Fe-oxyhydroxides, and Fe-oxides. Geochemically, the settling particles exhibited strong metal (e.g., Fe, Cu, Zn, Ga, Mo, Ag, Cd, and Pb) and S enrichment. The data indicate that the current direction, position of the trap (bearing and distance relative to the vent), and height above the bottom have strong impacts on the observations of the hydrothermal fluxes. The mean flux of particulate FeH, in the upper trap (225 m above the bottom (mab)) was 248 μg·cm−2·yr−1. However, in the dominant current direction (N90–135°), the FeH flux settling at the same distance was estimated to be 3.8–4.7 fold greater than this value. The settling flux of the FeH derived from the Wocan field decreased with increasing distance from the vents to a greater extent than the fields in the Atlantic Ocean and to a much greater extent than the fields in the Pacific Ocean. This difference can be explained by the much higher oxidation rates of the Fe (II) in the hydrothermal fields in the Indian and Atlantic Oceans. The settling fluxes in the upper and bottom traps (35 mab) were significantly different. The hydrothermal fluxes in the upper trap were influenced by the current direction, whereas the fluxes in the bottom trap were governed by sediment resuspension in addition to the current direction. Our data show temporal variations in the hydrothermal plume height and settling fluxes, which were largely attributed to the variations in the hydrothermal output. In addition, the temporal variability of the CaCO3 flux in the upper trap recorded the seasonal cycle of the primary productivity in the surface water.
•The current direction, height and bearing of the trap have a strong impact on the observations of hydrothermal fluxes.•The hydrothermal fluxes in the upper trap were mainly influenced by the current direction.•The hydrothermal fluxes in the bottom trap were governed by sediment resuspension in addition to the current direction.•The temporal variations in plume height and settling fluxes are largely attributed to the variations in hydrothermal output.
2,2':6',2″-Terpyridine (tpy) is a versatile moiety used in the construction of small novel molecules or polymers. Extending or coupling tpy with π-conjugation structures can result in interesting ...optoelectronic properties. This mini-review summarizes the significant progress made over the past decades in the study of tpy-containing π-conjugated polymers and their application in light-emitting and photovoltaic materials. When coordinated with metal ions, tpy exhibits immense potential for the synthesis of metallo-supramolecular or metallo-polymer materials. Therefore, tpy-based metallo-polymers are the primary focus of this study. Selected examples will be reviewed with a special emphasis on the properties of these functional systems, which can consequently help further their application in light-to-electricity or electricity-to-light conversion fields.
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