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Accurate in-situ crustal stress data are essential for excavation support design and long-term stability analysis of underground projects. We tested the main shaft of the Shaling Gold Mine for crustal stress using hydraulic fracturing technology, and the crustal stress state of 20 measurement points was obtained. The Brazilian test, uniaxial compression test, and acoustic emission test of the cores were conducted indoors to obtain the rock’s spatial inhomogeneity and strength distribution. We analyzed the relationship between the inhomogeneity of the rock and the hydraulic fracturing results. The analysis results show that the magnitude of the principal stress increases nearly linearly with the measurement depth, with the maximum horizontal principal stress value ranging from 20.78 to 45.2 MPa and the minimum principal stress value from 14.94 to 35.33 MPa. The average direction of the maximum horizontal principal stress is NW 65°. The inhomogeneity of each layer of the cores varies, and the inhomogeneity coefficient of the metagabbro is from 0.1 to 0.3. The number of acoustic emission signals under each intensity of the rock is basically the same, and the dispersion of the rock is small. The non-homogeneity coefficient of granite is up to 1.0, dominated by the acoustic emission signals generated by the intense-phase rupture at the late loading stage. The non-homogeneity of the rock affects the direction of expansion of the hydraulic fracture, and the angle\begin{document}$\varphi $\end{document}between the expansion direction and the maximum horizontal principal stress affects the measurement results of the horizontal maximum and minimum principal stresses and has a more significant effect on the horizontal minimum principal stress. The relationship between hydraulic fracture measurements and rock properties was analyzed, which is helpful for accurately detecting the distribution of stress fields in inhomogeneous strata.

Due to the lack of research on the embroidery types and needle techniques of the Gaoshan nationality of Taiwan, China, we used the two-dimensional verification method of literature and image analysis, Photoshop and Adobe Illustrator to illustrate their stitching techniques and to summarize the basic application rules of Gaoshan embroidery stitch. The results show that the Gaoshan nationality in Taiwan is closely related to the Han nationality. Since the Qing Dynasty, after the Gaoshan nationality traded with the Han nationality in Chinese mainland, the embroidery utensils of the Gaoshan nationality have been gradually improved. According to the degree of communication with the Han nationality, the embroidery of the Gaoshan nationality is divided into primitive ecological embroidery and immigrated embroidery. The primitive ecological embroidery has a strong primitive and religious atmosphere. The immigrated embroidery has been developed from the integration of Han and Gaoshan ethnic characteristics.

Targeted at the harmful effects of garment image retrieval at present, a new approach of garment image retrieval featured in satisfactory performance is proposed. In this study, the Grab Cut auto segmentation algorithm is applied first to segment garment images and extract the image’s foreground. And then, the color coherence vector (CCV) and the dominant color method are adopted to extract the color features to conduct garment image retrieval. The experimental data show that the Grab Cut auto segmentation algorithm is capable of extracting the foreground of garment images with either simple or complex background. Meanwhile, the data also indicate that compared with the garment image retrieval by extracting color features using CCV, extracting color features by dominating color method shows both higher accuracy and recall rates.

The west section of Nanchuan River City is an important part of the water ecological environment of Xining city, known as the urban meeting room. In order to find out the possible causes of algal blooms in the summer of 2022, water quality detection, aquatic organism identification and sediment analysis were carried out in the main landscape ponds of the west section of Nanchuanhecheng. The results showed that 52 species of phytoplankton were identified, including 4 species of cyanobacteria, 29 species of diatoms, 14 species of green algae, 3 species of cryptophytes and 2 species of gymnophytes. There were 66 species of zooplankton, including 22 protozoa, 29 rotifers, 9 cladicornis and 6 copepods. There were 18 benthic animals, including 4 annelids, 3 molluscs and 11 arthropods. According to the detection results of aquatic organisms, water quality and sediment, the causes of algal blooms were analyzed and corresponding measures were proposed to provide reference for subsequent control work.

CdTe photoelectric material with one-dimensional nanostructure and Bi2Te3 thermoelectric material were successively grown on FTO substrate by magnetron sputtering method for forming FTO/CdTe/Bi2Te3 heterojunction thin film. Whereafter, a power device was prepared by processing Ag electrode. The property of the device with light and heat synergy response was characterized by the V-t curve, which was collected through the circuit and optical path design. With the time difference between light and heat response, the curve of voltage-time was collected under the different light source, electrode contact point and light illumination direction. Meanwhile, the phenomenon of light and heat synergy response was identified with the illumination intensity of halogen and xenon light changeable. The results show that the synergy of photoelectric material and thermoelectric material in a single cell of CdTe/Bi2Te3 heterojunction can realize the light and heat synergy response, and it is anticipated to harvest solar energy from a wider solar spectrum.

Local resonance is a key reason for fatigue damage of gear housings.Local modals could be excited by vibration caused by gear meshing.Considering the shearer rocker arm for example,the local resonance characteristics of gear housing are analyzed in this paper.Finite element method is used to obtain the natural characteristics of housing and field testing with 0 load is employed to get the vibration acceleration values at the ratings.Local resonance characteristics are obtained by comparing frequency spectrum and natural frequencies.Housing wall thicknesses are selected as design variables to get the influence to natural frequencies.The results show that new frequencies which consist of meshing frequencies of different transmission stages occur and some of them can cause local resonance.Housing wall thicknesses should be changed to avoid local resonance.Excessive strain stress could be caused by local resonance and incur fatigue damage.This research could be a reference for resonance analysis and optimum design.

Thermochromic VO2 film was fabricated on quartz substrate through sputtering oxidation coupling method, and its optical properties were also investigated. Results show that the prepared VO2 film exhibits good thermo-optical switching performance under weak light irradiation, while large transmittance changes both in the visible and near-infrared light area. Under the condition of pulsed power laser irratiating, large optical modulation depth is also derived in the infra-red region. With the increase of pulsed laser energy, the scattering coefficient is gradually decreased, and the anti-laser irradiation ability is firstly appeared to have a decline trend after an initial ascent. The minimum transmittance value can reach to 7% and the laser damage threshold is about 50 mJ/cm2.

TiO2-based UV detectors with Ag antidot/TiO2/ITO sandwich structure were prepared by RF magnetron sputtering and colloidal crystal template technology. The microstructure and photoelectronic properties of the UV detectors were investigated by SEM, XRD, four point probe and semiconductor parameter instrument. The experimental results show that pore size of Ag antidot has an obvious effect on the photoelectronic properties of the detectors. With the increase of pore size, the dark current increases and the response time is prolonged, while the photocurrent is increased at first, then is decreased. Meanwhile, it is found that photoelectronic properties are optimum when the pore size is 4.2 μm. Antidot array electrodes with large pore size possess higher electrical conductivity, lower ultraviolet transmittance and higher recombination probability of electron-hole pair. Therefore, the pore size variation exhibits significant effluence on the photoelectronic properties of the UV detector.