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The automatic extraction of urban buildings based on remote sensing images is important for urban dynamic monitoring, planning, and management. The deep learning has significantly helped improve the accuracy of building extraction. Most remote sensing image segmentation methods are based on convolution neural networks, which comprise encoding and decoding structures. However, the convolution operation cannot learn the remote spatial correlation. Herein we propose the Shift Window Attention of building SWAB-net based on the transformer model to solve the semantic segmentation of building objects. Moreover, the shift window strategy was adopted to determine buildings using urban satellite images with 4 m resolution to extract the features of sequence images efficiently and accurately. We evaluated the proposed network on SpaceNet 7, and the results of comprehensive analysis showed that the network is conducive for efficient remote sensing image research.

Background: The essence of the plastic deformation of the material to be processed during the cutting process is the movement of dislocations. By increasing the density of dislocations, the material’s flow stress inevitably increases by raising the strain rate. Objectives: The three regions are divided quantitatively as thermal activation stage (101-3×103), nonthermal stage (10-3-101), and dislocation damping stage (above 3×103). Analyzing the chip metallographic diagram of the cutting process, it is believed that the strain rate effect is caused by two reasons. Methods: The three areas are based on the speed of growth and the control mechanism, presenting a more detailed and vivid explanation of these three areas. Using Hopkinson pressure bar (SHPB), the strain rate effect of duplex stainless steel S32760 is studied. Results: The greater austenite deformation is caused by the austenite deformation in S32760 compared to the ferrite softening effect and the insufficient softening effect in the plastic deformation of the material. Conclusion: The grain refinement is caused by the adiabatic shear zone from the deformation zone to the transition zone, making it difficult for dislocations to start slipping and increasing the flow stress.

The mechanical properties of S32760 duplex stainless steel under dynamic loading conditions at high strain rates are significantly different from those under quasi-static conditions. As a result of large strain, high strain rate, and high temperature, the analysis of the cutting process needs to factor in the influence of the viscous behavior of the material on the plastic deformation process. Based on the viscous effect of the two phases and the mixing rule, a mechanical threshold stress (MTS) constitutive model of S32760 duplex stainless steel considering the viscous effect is established to analyze the effect of strain rate on flow stress. An inverse identification method of the constitutive parameters based on Oxley's theory is proposed. The constitutive parameters of S32760 duplex stainless steel were reversely modified using an equal shear zone model and an orthogonal cutting experiment. The results show that the viscosity of the austenite phase was greater than that of the ferrite phase, and the strain rate had the greatest influence on the viscosity effect in the constitutive model. The prediction error of the constitutive model constructed in this manuscript was less than 4%, which had high accuracy.

Developing favorable charge transfer mode for photocatalytic hydrogen evolution in a photocatalyst is a promising way to enhance photocatalytic activity. In this study, MOF, decorated with different functional groups, was initially used as charge transfer mode convertor coupled with CdS/α-NiS-β-NiS. The NH2-UiO-66/CdS/α-NiS-β-NiS lead to twice and triple higher H2 evolution compared to (OH)2-UiO-66/CdS/α-NiS-β-NiS and UiO-66/CdS/α-NiS-β-NiS respectively under simulated sunlight. The NH2-UiO-66 provides suitable energy band structure to formed Z-scheme with CdS/α-NiS-β-NiS, which plays a synergistic role in the photocatalytic process. The loading of α-NiS-β-NiS significantly improves the visible light absorption ability and provides abundant active sites. As a result, the α-NiS-β-NiS/CdS/NH2-UiO-66 show considerable photocatalytic hydrogen production rate of 17.88 mmol h−1 g−1, which is 7.9 times and 2.5 times as high as-those of pure CdS and 7-α-NiS-β-NiS/CdS, and it also shows a prominent apparent quantum efficiency (AQE) of 14.7% at 420 nm. This work provides a new insight design a metal organic frameworks based heterojunction with highly-efficient photo-induced charge separation and excellent visible-light absorption ability.

Virtual reality technology involves computer graphics, artificial intelligence, network, sensor technology and many other aspects. It can use the powerful computing and graphics processing capabilities of computers to provide alternatives to the original and express its visual, tactile, and auditory technical means. According to archaeological research data And documentary records, virtual reconstruction and simulated display of the cultural heritage that has been wiped out. "Digital protection" of cultural heritage is a new way of protection, relying on computer technology, and the use of digital equipment to collect, save, process, output and disseminate the required information, including databases established on computer systems, So as to achieve the purpose of information sharing and dissemination. This article mainly studies the application research of virtual reality technology in the digital preservation of cultural heritage. Create an immersive environment for users, display the objects realistically in the virtual reality system, thereby digitizing the technical protection of cultural heritage; secondly, use the virtual environment model of material cultural protection to build and use the terrain to generate and edit The device imitates the terrain of the natural world to achieve its position and the effect of being in it. Finally, the radial basis function is used to calculate the value in the virtual environment, so that the digital preservation of cultural heritage is more accurate. Experimental data shows that 35.54% and 64.46% of users are more likely to use the handle to interact with three-dimensional objects. They believe that the speed of the handle has changed and the control is more precise. Experimental results show that: The virtual environment reality technology specification is more efficient than the original technology in the process of digitizing cultural heritage.

Objective This article aims to provide a better understanding of ultrasonography and immunohistochemistry of secondary nonhematological tumors of breast. Methods The study reviewed the ultrasound findings and immunohistochemical features of nonhematological metastatic breast tumor cases found in patients of West China Hospital, Sichuan University from 2007 to 2019. Each case was categorized as secondary breast malignancy using histopathological results. Results Fourteen cases were identified from West China Hospital database. Ten cases originated in the lung, 2 cases in the stomach, 1 case in the ovary and 1 case of neuroendocrine carcinomas. Fourteen masses were evaluated. Ultrasound findings showed that tumors were hypoechoic (14/14), irregular (13/14), indistinct margin (13/14), along a long axis parallel to the skin (11/14), lacked vascularity via color doppler flow imaging (9/14). Eight cases showed no posterior features. Calcification was found in 1 case of lung adenocarcinoma that had metastasized to the breast. Abnormal axillary lymph nodes were detected in 5 cases. Immunohistochemical analysis showed that estrogen receptor (ER) and progesterone receptor (PR) were both negative in 11 cases, including gastric and lung cancer metastasis. One case of ovarian metastasis was positive for ER and negative for PR. Six patients were positive for cytokeratin 7 (CK7) and negative for cytokeratin 20 (CK20), including lung and ovarian carcinoma metastasis. Thyroid transcription factor-1 (TTF-1) was positive in 9 of 10 pulmonary carcinoma metastases. The patient of ovarian metastasis was positive for Wilms' tumour 1 (WT-1) and carbohydrate antigen 125 (CA125). Two cases from gastric metastasis were positive for caudal-type homeobox 2 (CDX2). Conclusion Although breast ultrasound is not useful in distinguishing metastases from primary breast cancer, it is helpful in diagnosing breast lesions as oncological diseases and provide evidence for further examination of patients. Immunohistochemistry plays an important role in distinguishing secondary breast cancer from primary, especially in patients without tumor history.

Today, with the rapid development of urbanization, the ecological and environmental problems of the city have become increasingly serious and have become the focus of the world. The most important issue facing the majority of ecological workers is how to apply the theory of ecology to solve today’s problems. The various environmental problems faced in urban life and the sustainable development of the city’s ecological civilization. How ecological planning is used to coordinate the relationship between people and the natural environment and natural resources is increasingly gaining attention and expanding the range and scope of its applications. However, as an ecological suitability analysis based on ecological planning, many analytical methods and systems are still being explored and developed due to the geographical complexity and factor diversity involved. In recent years, with the rapid development of computer hardware and software technology, pattern recognition has received more and more attention, pattern recognition and image processing technology has become more and more perfect, and has been successfully applied in more and more fields. This thesis begins to focus on the urban ecological suitability content based on pattern recognition technology and image processing. The main contents of this thesis include: introducing the background of urban ecological suitability and the status quo of ecological suitability analysis and existing research methods. According to the structure of the urban ecosystem and the national standards for the construction of ecological systems and ecological cities, an indicator system for ecological suitability evaluation is established. A pattern recognition system and common pattern recognition and image processing methods are introduced. Based on some common evaluation methods and models, the pattern recognition technology theory and image processing technology are introduced into the urban ecological suitability analysis. Based on the image system theory and vector projection principle, the ecological suitability analysis is established. Associated projection model. The model considers the evaluation sample and the quality standards at each level as vectors, and respectively projects the same vector ideal. Based on establishing the ecological suitability evaluation index system and standards, the ecological suitability was evaluated by using the model.

This study aimed to construct a breast ultrasound computer-aided prediction model based on the convolutional neural network (CNN) and investigate its diagnostic efficiency in breast cancer. A retrospective analysis was carried out, including 5000 breast ultrasound images (benign: 2500; malignant: 2500) as the training group. Different prediction models were constructed using CNN (based on InceptionV3, VGG16, ResNet50, and VGG19). Additionally, the constructed prediction models were tested using 1007 images of the test group (benign: 788; malignant: 219). The receiver operating characteristic curves were drawn, and the corresponding areas under the curve (AUCs) were obtained. The model with the highest AUC was selected, and its diagnostic accuracy was compared with that obtained by sonographers who performed and interpreted ultrasonographic examinations using 683 images of the comparison group (benign: 493; malignant: 190). In the model test with the test group images, the AUCs of the constructed InceptionV3, VGG16, ResNet50, and VGG19 models were 0.905, 0.866, 0.851, and 0.847, respectively. The InceptionV3 model showed the largest AUC, with statistically significant differences compared with the other models (P

Due to the increasing concern with physical and mental wellbeing, people realize the need to get away from the routines of domestic life and travel to tourist destinations. We propose the notion of...

Home, as a site of daily dwelling and a set of meanings, offers a way into studying the relationship between lifestyle and profit in tourist destinations. Situated in the context of lifestyle entre...

The rapid separation and transport of photogenerated carriers are pivotal toward enhancing the photocatalytic performance. Herein, CdS nanoparticles are grown in situ on oxygen deficiency-rich WO3−x nanosheets, successfully providing a direct Z-scheme CdS/WO3−x heterojunction to enhance photocatalytic hydrogen production. We demonstrate an effective electron collection in the Z-scheme CdS/WO3−x heterojunction by regulating the relative content of WO3−x. The optimized CdS/20 wt% WO3−x (CW20) affords a high photocatalytic hydrogen production rate of 6545.3 μmol g−1 h−1 in lactic acid aqueous solution under visible light (400–800 nm), which is about 54.1 times that of pure CdS (121.0 μmol g−1 h−1). In addition, CW20 also provides a considerable external quantum efficiency (EQE) of 10.03% at λ = 420 nm. The best-performing CW20 sample is explored by cyclic stability experiment and XRD characterization after hydrogen production, which reveals the robust stability of CW20. The excellent photocatalytic activity can be attributed to the formation of a Z-scheme CdS/WO3−x heterojunction, resulting in an efficient spatial separation of photogenerated carriers. Electron and hole catalytic centers are maintained in two separate components to minimize the adverse products of photocatalytic hydrogen production. This study uncovers the role of oxygen deficiency based on the Z-scheme heterojunction in affecting electron transfer and reaction sites, opening new opportunities for achieving efficient hydrogen production.

Developing well-designed architectures plays a decisive role in accelerating photo-generated carrier transport in composite photocatalysts. Herein, a microporous sulfur-doped (S-doped) NH2-UiO-66 bridged ZnIn2S4/MoS2 sheet heterostructure photocatalyst is synthesized through thermolysis of sulfur rich precursors to functionalize the organic ligands of NH2-UiO-66 to boost photocatalytic efficiency. XPS spectra confirm the existence of S-doped NH2-UiO-66, and Raman spectra show transition metal-assisted sulfuration instead of carbonization. FT-IR spectra further confirm the formation of Zn–O–C covalent bonds at the interface between NH2-UiO-66 and ZnIn2S4. In particular, the Zn–O–C bonds preserve the energy of photo-generated electrons and inhibit the energy relaxation of electrons at the interface of the heterostructure. In addition, NH2-UiO-66 with a high photocatalytic response greatly facilitates the transport of photo-generated electrons not only as an electron transport bridge but also as an electron donor. Profiting from the unique design of the ternary composite, the sample exhibits excellent PHE performance. The obtained ZnIn2S4/NH2-UiO-66/5%-MoS2 (5.69 mmol h−1 g−1) exhibits the highest H2 evolution rate, which is 15 and 1.9 times higher than those of ZnIn2S4 (0.369 mmol h−1 g−1) and 5%-MoS2/ZnIn2S4 (2.93 mmol h−1 g−1), respectively. In addition, the apparent quantum efficiency of the ZnIn2S4/NH2-UiO-66/5%-MoS2 composite (7.95%) is higher than that of the 5%-MoS2/ZnIn2S4 composite (3.12%) at 420 nm. This work provides new insight into designing novel and highly efficient photocatalysts for photocatalytic hydrogen evolution.

With the rapid development of image video and tourism economy, tourism economic data are gradually becoming big data. Therefore, how to schedule between data has become a hot topic. This paper first summarizes the research results on image video, cloud computing, tourism economy, and data scheduling algorithms. Secondly, the origin, structure, development, and service types of cloud computing are expounded in detail. And in order to solve the problem of tourism economic data scheduling, this paper regards the completion time and cross-node transmission delay as the constraints of tourism economic data scheduling. The constraint model of data scheduling is established, the fitness function is improved on the basis of an artificial immune algorithm combined with the constraint model, and the directional recombination of excellent antibodies is carried out by using the advantages of gene recombination so as to obtain the optimal solution to the problem more appropriately. When the resource node scale is 100, the response time of EDSA is 107.92 seconds.

Tourist destinations with cultural heritage have arisen as a prominent issue in tourism literature. Creating a positive image of the destination can influence tourists’ satisfaction and willingness to return. The goal of this research is to investigate the relationship between destination image formation (DIF), tourist satisfaction (TS), and tourist trust (TT). As a result, the structural relationships between local community participation (LCP), authenticity (A), access to local products (ALP), TS, and TT were investigated in this study. This study used a quantitative approach based on a survey of 644 domestic and foreign tourists visiting the Guangdong cities of Guangzhou, Foshan, and Shenzhen. The statistical software SmartPLS 3.3.3 was used to determine the relationship between variables in the research model using structural equation modeling. The outcomes show a positive correlation between LCP, A, and ALP, which led to tourist satisfaction and, eventually, tourist trust. It is concluded that the DIF and TS may result in increased tourist trust. There is also a discussion of additional theoretical contributions, practical implications, and limitations. The outcomes of this study will help to shed light on the variables that encourage and promote tourism in developing countries.

Cultural heritage tourist destinations have emerged as a hot topic in tourism literature, but there have been relatively few studies that determine the role of the involvement of local participation in either tourism planning or the decision-making processes of tourists. The connection between local community participation (LCP), authenticity, access to local products, destination visit image, tourist satisfaction, and tourist loyalty is thus relatively unexplored in the literature. This study used a quantitative approach based on a survey with 406 respondents visiting the city of Kaiping in Guangdong, China. The proposed hypotheses were empirically tested with SPSS and Analysis of Moment Structures. The resulting outcomes indicated a positive correlation between LCP, authenticity, and access to local and destination visit image, which led to tourist satisfaction and ultimately resulted in tourist loyalty. Additional theoretical contributions, practical implications, and limitations were also discussed.

Tourism is a way of recreation, which involves a person’s travel to another city, country, and even to another continent. Travel is different, and any connoisseur can choose a vacation to their liking: active, educational, wellness, religious, beach, or rural. Tourism helps people escape from everyday problems, learn something new, and get an unforgettable aesthetic satisfaction. Also, such a vacation helps not only to learn the cultures of other countries and peoples but also contributes to the personal development of any traveller. In general, it allows people to combine relaxation with learning new things. However, different tourists have different preferences, so their motivation to visit specific cities, countries, or regions are also different. This study aims to provide tourists in China with an up to date and specific typology based on centricity and experience. Besides, the motive behind the work presented in this paper is to identify the different types of tourists in China, analyse their preferences, and as a result, create their holistic profile. Several studies from China already have information on the factors that influence this typology. In general, they include characteristics of travel (for example, on-site activities, prior knowledge) and some sociodemographic characteristics. This study shows that, in practice, there are small differences in preferences between local day trippers and those travelling for several days from remote regions of China.

This study examines China’s urban–rural transition in the process of development and change. Regarding tourism as a discourse of difference, it focuses on a rural ethnic community, Jiabang, in Southwest China. It aims to highlight the role of tourism in providing a stimulus for the creation of a local group identity that subverts wider discourses of rural areas. With the goal of understanding how toured places are imagined, presented and consumed, this study utilises mixed data sources collected from tourism promotional materials and ethnographic fieldwork. The findings suggest that the forces behind the touristic place creation and consumption are both integral to and the result of the changing attitudes and perceptions of people and places in contemporary China.

An oxygen deficiency modified Z-scheme CdS/WO3-x nanohybrid with MoS2 as the cocatalyst was synthesized by a microwave hydrothermal method and was used for photocatalytic hydrogen production under visible light irradiation. Loadings of WO3-x and MoS2 as well as the synthesis time of the microwave-assisted hydrothermal process were optimized, and the physicochemical and optical properties of the as-prepared photocatalysts were characterized by various techniques. Results showed that the material with 30 wt% of WO3-x, 0.1 wt% of MoS2 and a preparation time of 120 minutes exhibited the most desirable morphology and structure for hydrogen production. The maximum hydrogen production of 2852.5 μmol g-1 h-1 was achieved, which was 5.5 times that of pure CdS (519.1 μmol g-1 h-1) and 1.5 times that of CdS/30 wt% WO3-x (1879.0 μmol g-1 h-1), and the external quantum efficiency (EQE) reached 10.0% at 420 nm. The improvement of photocatalytic performance could be attributed to the Z-scheme formed between CdS and WO3-x and MoS2 as an electron trap. It is worth mentioning that the size of the composite had a negative correlation with the H2 production rate.

With the improvement of the material standard of living, the demand of the people for spiritual culture continues to increase. In terms of tourism, people have gradually shifted from simple tourism needs to integrated tourism needs. Tourism has become an effective way for people to expand their horizons and enrich their spiritual world. Tourism is one of the first industries to apply network technology. After long-term exploration and innovation, tourism e-commerce has developed rapidly. Coupled with the advent of the era of big data (EBD), the concept of customized tourism has gradually entered people’s lives. This paper mainly introduces the research on the impact of e-commerce tourism on custom tourism in the EBD and intends to provide some ideas and directions for the good development of custom tourism. This paper proposes a research strategy on the impact of tourism e-commerce on customized tourism in the EBD, including related theoretical research methods, random forest algorithms, support vector machine classification algorithms, and Bayesian estimation algorithms, which are used to customize tourism e-commerce in the EBD, and research experiment on the impact of tourism. The experimental results show that 79.84% of customers are willing to purchase related products again after experiencing travel customization services using big data technology. By using the various characteristics of tourism big data for data mining and classification, it provides users with personalized travel search services. At the same time, big data technology can provide basic technical support for customized tourism development, which shows that it can also provide customized services for users.

Consumers pay attention to personalized needs in tourism, and traditional travel methods have been unable to meet the needs of social development. As an innovative model, smart tourism embodies a new tourism development concept and management mechanism. This article aims to analyze the problems existing in the development of smart tourism in the A place to promote the healthy and sustainable development of the tourism industry in the A place. This paper investigates the development of smart tourism in A place and analyzes the satisfaction of tourists. The overall satisfaction of tourists is high, but the satisfaction of transportation and mobile terminals is low. The score ratio is 83.18% and 84.78%. Through interviews, it is found that customers think that waiting in the queue is too long, and the real-time parking situation cannot be intelligent and convenient. On the mobile terminal, customers think that downloading APP is too troublesome. According to the shortcomings and problems in the development of smart tourism, corresponding improvement strategies are proposed to enhance the tourist experience of tourists and promote the balance and sustainable development of smart tourism.