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Under the conditions of deep high stress, weak surrounding rock, and strong mining influence, the surrounding rock of deep-buried roadway frequently experiences large deformations, the controllability of large deformation support for this type of surrounding rock is generally poor, and the conventional anchor bolts often break or fail to anchor due to their low elongation rate, which cannot adapt to the large deformation of the roadway, resulting in the risk of roof caving in the roadway. The constant resistance device by using composite expansion pipe (CRD-cep) used in conjunction with cable bolt has been invented. The main structures include a stop end cover, an expansion pipe, an integrated tray and a conical lock. The conical lock overcomes the approximately constant composite resistance generated by the “expansion grinding” of the expanding pipe, thus, the constant resistance of the cable bolt during the large deformation process of the surrounding rock is achieved. The mechanical characteristics and working stability of the resistance stabilizer are improved by theoretical analysis, numerical simulation and static tensile testing and other comprehensive research methods, and the influence of the expansion increment and lock cone angle of the composite expansion tube constant resistance device on the deformation of the expansion pipe and the composite resistance of the CRD-cep has been understood. The test results indicate that the composite resistance of the CRD-cep is mainly divided into two processes: the fast rising resistance stage and the near constant resistance stage, and the nearly constant resistance section as the main stage reaches 85% to 90% of the entire test process. The lock cone angle and expansion increment directly affect the deformation of the expansion pipe and the mechanical characteristics of the CRD-cep. When the lock cone angle is less than 20°, the deformation of the expanding pipe is uniform and the composite resistance of the CRD-cep is stable. The expanding increment determines the size of the CRD-cep. The required constant resistance of the cable bolt can be obtained by adjusting the expanding increment. When the diameter of the anchor rope used is 17.8 mm, the lock cone angle is 15° and the expansion increment is 5 mm, the constant resistance of the CRD-cep is about 265.92 kN, when the diameter of the anchor rope used is 21.8 mm, the lock cone angle is 15° and the expansion increment is 8 mm, the constant resistance of the CRD-cep is about 424.15 kN, and the working state is stable and reliable, which can better meet the constant resistance support requirements of large deformation roadway. The CRD-cep has the characteristics of strong working stability, adjustable constant resistance stroke and resistance, simple structure, and convenient installation, which is an effective supplement to the control technology of surrounding rock in large deformation roadway.

The industrial production requires the input of water, land and energy, and the water-land-energy interaction generates carbon emissions. Investigating the industrial water-land-energy-carbon nexus and exploring the influencing factors of the carbon emissions help promote the intensive use of water resources, land resources, and energy, as well as the low-carbon development of industry. This paper applied kernel density estimation and spatial auto-correlation analysis to explore the spatio-temporal variation of industrial carbon emission effect of water and land use and the industrial matching status of water and land resources in China, and then analyzes the influencing factors to industrial carbon emissions by introducing water and land resource factor into Kaya identity and Logarithmic Mean Divisia Index (LMDI) model. The main conclusions are: (1) From 2006 to 2020, China's industrial carbon emissions increased by 82.02%. The industrial carbon emission intensity of water use (CEIWU) and the industrial carbon emission intensity of land use (CEILU) increased by 158.02% and 55.53% respectively. The inter-provincial difference of CEIWU and CEILU expanded considerably, and the number of provinces with high CEILU had a large increase. (2) The industrial matching index of water and land resources (MIWL) in China showed a fluctuating downward trend, presenting great spatial clustering, and the provincial MIWL were mainly concentrated in the H-H and L-L regions. (3) The contributing and inhibitory effect of each influencing factor varied on regional and provincial level. The economic output of water use is a contributing factor to all regions and provinces, while the MIWL is an inhibitory factor to all regions and provinces.

China is entering a stage of rapid development. To ensure strategic development, more regions have begun to integrate and reconstruct regional spaces by strengthening their regional cooperation and focusing on top-level design. The scenic line is a physical space that integrates ecological landscape resources, cultural carriers, and industrial foundations into regional spaces. Its construction is of considerable importance for aggregating functions and supporting regional integration. Sichuan, China, has some of the most abundant bamboo resources worldwide, and the bamboo scenic line has Chinese characteristics. This study takes 12 areas suitable for bamboo growth in Sichuan Province as research objects using GIS technology combined with methods such as suitability evaluation. An ecological base layer, landscape pattern layer, facility foundation layer, and industrial development layer were developed as the four element layers, along with their influencing factors. The weights of the factors were assigned using the entropy method, and the cost path was analyzed for the resistance side, branch point, and context. A suitability evaluation system was constructed for the scenic line, and a provincial organic development pattern of “one point, two axes and three belts” was formed for the bamboo scenic line, which can provide guidance for planning and design.

City green space can promote people’s health and aesthetic satisfaction; however, most extant research focuses on suburban forests and urban parks. Urban landscape forests have important ecological and aesthetic value for urban environments. This study conducted a visual stimulation to examine the impact of four common spatial element combinations in urban landscape forests on teenagers’ recovery potential and preference. The results indicate that urban landscape forests had positive physiological and psychological effects on adolescents, including decreased blood pressure, improved heart rate, reduced anxiety, and improved recovery ability. Diastolic blood pressure relief performance was better among males than females. In addition, a stepwise linear regression analysis was performed to explore the quantitative relationship between spatial elements and recovery and preference values. The results demonstrate that water elements were a significant predictor in the quantitative relationship between spatial elements in landscape forests and restoration and preference values. Terrain, flower, and shrub elements did not have a significant effect on overall restoration and preference values. This study highlights the intervention value of urban landscape forests in promoting the health and well-being of adolescents, with implications for future planning and design of urban landscape forests.