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Owing to advancements in satellite remote sensing technology, the acquisition of global land surface parameters, notably, the leaf area index (LAI), has become increasingly accessible. The Sentinel-2 (S2) satellite plays an important role in the monitoring of ecological environments and resource management. The prevalent use of the 20 m spatial resolution band in S2-based inversion models imposes significant limitations on the applicability of S2 data in applications requiring finer spatial resolution. Furthermore, although a substantial body of research on LAI retrieval using S2 data concentrates on agricultural landscapes, studies dedicated to forest ecosystems, although increasing, remain relatively less prevalent. This study aims to establish a viable methodology for retrieving 10 m resolution LAI data in forested regions. The empirical model of the soil adjusted vegetation index (SAVI), the backpack neural network based on simulated annealing (SA-BP) algorithm, and the variational heteroscedastic Gaussian process regression (VHGPR) model are established in this experiment based on the LAI data measured and the corresponding 10 m spatial resolution S2 satellite surface reflectance data in the Saihanba Forestry Center (SFC). The LAI retrieval performance of the three models is then validated using field data, and the error sources of the best performing VHGPR models (R2 of 0.8696 and RMSE of 0.5078) are further analyzed. Moreover, the VHGPR model stands out for its capacity to quantify the uncertainty in LAI estimation, presenting a notable advantage in assessing the significance of input data, eliminating redundant bands, and being well suited for uncertainty estimation. This feature is particularly valuable in generating accurate LAI products, especially in regions characterized by diverse forest compositions. [ABSTRACT FROM AUTHOR]

The internationalization of higher education in Jiangxi Province is not only the internal requirement of the development of higher education but the actual demands of Jiangxi's economic development. However, quite a few problems are hindering it, such as laggard ideas about education internationalization, low level of staff internationalization, dissatisfying overseas enrollment, poor international cooperation in running schools, small scale of the international exchanges of information and so on. As a result, in order to promote the internationalization of Jiangxi's higher education, some countermeasures should be taken: enhancing understanding, updating ideas and accelerating relevant projects; sorting out relations and perfecting systems according to actual demands; confirming objectives, giving guidance according to different types and developing individuality; improving teaching quality and developing programs; expanding channels and creating conditions in accordance with local conditions.

Chemiresistive sensing materials capable of efficiently identifying specific flammable gases are imperative. Although plenty of high-performance chemiresistive sensors have been developed in related fields, the high selectivity response to a single flammable gas at room temperature is still a great challenge. Conventional single chemiresistive metal oxide semiconductor materials exhibit similar response characteristics to flammable gases at high temperatures, while arrays are limited by high cost and miniaturization. Herein, the unique gas discrimination based on a monolithic MOF-derived chemiresistive sensor is achieved with photoexcitation at room temperature. 5.0Pd@ZnO exhibits a typical p-type semiconductor response (200 ppm, 52.89) to H2, while it displays a typical n-type semiconductor response to other flammable gases (CO, MeOH, EtOH, and H2S response of −25.15, −13.63, −49.92, and −40.36, respectively), which indicates that H2 can be fully identified merely from the original electrical signal. Meanwhile, the as-prepared sensors combined the advantages of MOF and MOS materials, and exhibited high linearity response, favorable repeatability, and long-term stability. The special response characteristics of the sensor to each flammable gas have been explored in detail, and the distinct effects of two different Pd surface states on gas molecules are discovered by DFT calculations. The mechanism of the high-selectivity response behavior at room temperature is systematically analyzed. This work provides a solid reference and feasible solution for the development of high-selectivity room temperature sensors. [ABSTRACT FROM AUTHOR]

The joints and fissures in a natural rock mass can affect the mechanical properties of the rock mass, the propagation of a blasting stress wave, and the blasting effect of the smooth surface of roadways. In the process of roadway drilling and blasting, there will inevitably be some joints between the two blast holes. Taking the joint angle as the starting point, this paper studies the rule of rock explosion crack propagation and stress variation when there are joints with different angles between two blast holes and analyzes the influence of joints on rock mechanical properties and blasting effects. The numerical simulation method and the software ANSYS/LS-DYNA are used to establish 7 rock mass models with various joint angles. When there is no joint between two holes and joints of 15°, 30°, 45°, 60°, 75°, and 90°, the propagation of explosive cracks and stress variations in the rock mass are discussed. The results show that the joints at different angles have obvious guiding and blocking effects on the propagation of explosive cracks, and as joint angles increase, the guiding effect becomes more apparent and the blocking effect becomes weaker. The effective stress of the rock mass will vary depending on the angles of the joints between the hole and the joint. As the joint angle increases, the joint's influence on the reflection and superposition of stress waves gradually weakens, and the peak value of the effective stress of the rock mass gradually decreases. The peak effective stress of the rock mass on the blasting side of the joint is similarly impacted by the superposition of stress waves, and the extreme value may be seen at the critical node of each change curve. The explosive crack will break through at the critical location because the maximal effective stress of the rock mass is distributed in a "W" form on the blasting side of the joint. [ABSTRACT FROM AUTHOR]

The ongoing shift from an industrial to a digital economy is a significant global phenomenon. However, the driving forces behind and the tactical approach to digital transformation are still unclear to the construction industry, thereby posing challenges for construction enterprises seeking to undergo digital transformation. Therefore, this paper conducted an investigation on the subject, including the following: (1) the 17 influencing factors in the complex system of digital transformation of construction enterprises were screened and summarized from four perspectives: Environment, Technology, Organisation, and Resources. The attributes of the influencing factors were analyzed using the Decision-Making Experimentation and Evaluation Laboratory (DEMATEL) method, and the key factors were identified. (2) The Total Adversarial Interpretive Structure Model (TAISM) method was used to develop a multi-perspective adversarial recursive structure model with integrated impact values, which reflected the interrelationships between the influencing factors and the hierarchical structure. (3) Based on the analysis of the influencing factors of digital transformation of construction enterprises, the clear path mechanisms were elucidated and suggested measures from the internal and external perspectives of government and construction firms were recommended. The results can offer theoretical backing and serve as a stepping stone for the digital transformation of the construction industry. [ABSTRACT FROM AUTHOR]