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Tree growth is the most important factor in determining the carbon sequestration processes of forest ecosystems. However, the growth phenology (seasonal growth pattern) and responses of tree growth to climatic variables vary considerably among different species, especially between deciduous and evergreen species. Thus, it is crucial to explore the seasonal growth patterns of different tree species in relation to climate to better understand the responses of tree physiology to climate changes, especially in mixed-species forest stands. In this study, we monitored the daily basal area increments of 220 individuals belonging to 15 common broadleaved tree species, nine deciduous and six evergreen species, in mixed-species experimental stands in subtropical China and analysed the relationships between radial stem growth and seasonal climate at a high-temporal resolution. We fitted daily increments of stem diameters with four frequently used nonlinear models and chose the best model for each species. The results showed that the evergreen trees grew faster than the deciduous trees, both annually and within the growing season. The tested nonlinear models (Korf, Weibull, logistic and Gompertz) produced good fits for the growth patterns of all species. Overall, the evergreen species began stem growth earlier and finished later during the growing season than that of the deciduous species. Within the growing season, the radial growth of trees in mixed stands containing both types of species was strongly positively correlated with humidity. In spring, increases in both temperature and moisture increased the daily relative basal area increment of all species. Maximum growth rates occurred when the soil water content reached its highest level and gradually decreased when the soil water content decreased. In summer, high temperatures combined with low amounts of precipitation led to heat-induced summer drought, to which the evergreen trees appeared to be more tolerant than the deciduous trees, which was reflected in the reduced stem growth of the latter. These results indicate the different climate-dependent seasonal growth strategies of evergreen and deciduous trees related to the trade-off described by the leaf economics spectrum, i.e., short-lived leaves with higher assimilation rates in deciduous and longer-lived leaves with a greater drought tolerance in evergreen species.

Advanced Driver Assistance System (ADAS) and Artificial Intelligent (AI) are the important issue in recent years, autonomous car plays an important role in whole ADAS. To detect the environment surround the car, the sensor might be sensitive and immediate. LiDAR (Light Detection and Ranging) uses Laser to get the reflectivity from the surrounding objects. For clustering the objects with point cloud, the density of the point cloud still sparse, making the cluster result completely, we implement a system combines LiDAR and multi-view image, the depth image is generated by multi-view can help us to cluster the object in point cloud clearly. In addition, we use CORDIC (Coordinate Rotation Digital Computer) EEAS (Extended Elementary Angle Set) architecture to decode the package data that collected from Velodyne HDL-64E. By using the flow of digital chip design, we reduce the power consumption and accelerate the speed. The proposed system achieves 91.09% accuracy and the processing time is 0.757 second.

Autonomous vehicles and robot are more and more popular, and it is important to sense the environment for autonomous vehicles and robot. LiDAR is a very powerful device, it can capture the distance and contour of object precisely and quickly. And the scanning range is very wide. we use 3D LiDAR and neural network to detection the environment. We get the data packet from LiDAR, and decode the data packet to 3D point cloud coordinate. Then extract the drivable road by neural network and mark the obstacle.

Habitat degradation and loss threaten the survival of many species, especially vertebrates. The establishment of nature reserves is an efficient approach to protect biodiversity. However, fulfilling conservation targets depends largely on the effectiveness of these nature reserves in capturing the targeted species. In this study, we developed a distribution database of threatened terrestrial vertebrates in China, then explored the patterns of the threatened terrestrial vertebrates and evaluated the effectiveness of current nature reserves in terms of their conservation, further identified the conservation priorities for these species in China. We found 452 threatened terrestrial vertebrates widely distributed across China, especially in mountainous and forested regions in southern China. The current nature reserve network is inadequate to capture the threatened vertebrate species. The nature reserves were found to cover 30.47% of the hotspots and 38.65% of the ranges of these species on average, with quite a few conservation hotspot and species gaps. We further propose to either systematically plan and fix current nature reserves or add new protected areas in Yunnan Province and mountainous regions in southeast China.

With the improvement of requirements for the building, and the effects of various factors for some existing steel structure building during the long-term service process, structural function is damaged, which requires reinforcement for existing structures to meet the requirements of its use of the function. This paper systematically introduces the research and application of steel structure member on strengthening aspects, which is prepared for the research of steel column reinforced by enclosed reinforced concrete under axial compression with initial compressive load. According to development and characteristics of steel columns reinforced by enclosed reinforced concrete under axial compression, this paper analyzes the common working mechanism of steel structure and concrete after reinforcement, and introduces the calculation method and its engineering application in our country.

With the lapse of time, the carrying capacity of early steel structure buildings which affected by various factors in the process of long service has dropped. Meanwhile, the use function of buildings has been asked for a higher level with the improvement of people's living standard. In this case, the assessment and reinforcement on buildings are particularly important. In this paper, the characteristics and mechanical properties of axially loaded steel columns strengthened by welding under load and axially loaded steel columns strengthened by enclosed reinforced concrete under load, the mechanism of steel and concrete work together and the reduction coefficients of steel and concrete of enclosed reinforced concrete have been systemically introduced. To pave the way for the following researches of steel numbers reinforced under load.

To solve the problem of SRHC beam strengthened with FRP(Fiber Reinforced Polymer),a new renovate SRC beam of strengthened with FRP has been brought forward in this paper.In this paper, the load-deformation process,flexural failure characteristics of SRHC beams strengthened with FRP were researched by a new practical superposition method, the damage and bearing capacity under the limitation failure of SRHC beam strengthened with FRP are studied. In addition, according to the different positions of central axis and section of steel, the compressive region height under the limitation of three destroy is put forward. Compare the relation between the compressive region height with the distance of top flange of steel to the compression flange of concrete, hence, a applied formula to the different flexural capacity under the limitation failure of beams strengthened with FRP, the concept of presented equation is convenient for use.

This article aims to study the calculation for shear capacity of SRHC (Steel Reinforced High-Strength Concrete) members restrained with CFS (Carbon Fiber Sheet). Experimental study, theoretical analysis and calculation simulating are integrated in this article for the research of the shear failure characteristics and effect of various parameters on their behavior of SRHC members restrained with SFC on the basis of existed SRHC members tested results. The shear strength formula of steel reinforcement high-strength concrete short columns restrained with CFS is put forward, which based on the superposed strength method. This method on the basis of the load-deformation process of CFS is similar to hooping. The results indicate that the shear capacity of SRHC columns restrained with CFS is higher than SRHC columns. And, due to the axial compression ratio, shear span ratio and the amount of reinforcement influence the shear capacity of the FRP materials. So, these three kinds of factors are also the influencing factors of shear capacity of SRHC members restrained with CFS. The effect of the internal concrete restrained with CFS is good because of the function of CFS is equal to hooping and the strain of CFS is bigger than the strain of steel, so this simple calculation method is safe , which may be useful for further study and engineering design.