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Geothermal energy, as an emergent source of power, has consistently been a focal point of scholarly investigation both domestically and internationally, with a particular emphasis on the prediction and assessment of its extraction efficiency. In common geothermal extraction projects, the seepage behavior of water within the fractures for the geothermal reservoirs significantly impacts the efficiency of resource extraction. This study introduces an interdisciplinary fractal model for geothermal extraction. An enhanced fractal theory, tailored for geothermal reservoirs, is proposed, employing four innovative fractal parameters— fracture fractal dimension, fracture tortuosity fractal dimension, fracture roughness parameter, and maximum fracture length—to quantitatively characterize the fracture structure. This refined fractal theory is applied to geothermal reservoir extraction under the complex thermal-hydromechanical coupling. The findings indicate that the proposed structural parameters effectively characterize the micro-macro interactions during the geothermal extraction process. Significant evolution of these fractal parameters is observed throughout the extraction process. Furthermore, there is an inverse relationship between geothermal extraction efficiency and two key fractal parameters—fracture tortuosity fractal dimension and fracture roughness parameter—while the reservoir stress is directly proportional to these parameters.

With the rapid development of energy internet, dispatchers need to learn more knowledge with wider scope and fast update speed. It’s urgent to realize the knowledge electrification, knowledge systematization, knowledge visualization and knowledge sharing of power grid dispatching. Firstly, this paper studies the definition and traits of knowledge graph, deeply analyses the key technologies of knowledge graph construction. Secondly, considering the contents and requirements of power grid dispatching business as well as the internal relationship of basic theoretical knowledge of power grid operation analysis, a method of constructing AC/DC power grid dispatching knowledge property graph is proposed. Finally, a practical example of a regional power grid knowledge graph is built to verify the effectiveness and practicality of the proposed method.

Guidance and control method was presented in this paper for flight vehicle with a strap-down seeker. Firstly, an extended Kalman filter was constructed in LOS (line of sight) coordinate system to estimate the guidance signal based on the information measured by strap-down seeker and inertial measurement unit. Secondly, an optimal guidance law which could reduce the target maneuvering and guidance system dynamics was proposed. Thirdly, three-loop acceleration autopilot with pseudo-angle of attack feedback was presented to control the flight vehicle. Finally, the proposed methods were simulated under typical condition. The simulation results demonstrated that the proposed methods were valid, and good performance could be achieved by the guidance and control method with the guidance signal estimated by the extended Kalman filter.

Network Scalability is an important step in the development of UWB indoor localization system. Owing to its fine resolution and robustness in cluttered environments, UWB signals are well suited for localization purposes as they allow high ranging accuracy. TDOA algorithm based on UWB indoor localization system can achieve high-precision positioning but it requires each anchor clock synchronization. This paper mainly studied the optional of master anchor based on TDOA algorithm. It becomes an effective way to adapt to the complex communication environment. Then realized the network scalability in multiple anchor conditions and finally evaluated the performance of master anchor optional algorithm on a realistic indoor scenario. A localization error analysis on UWB indoor positioning system was performed. The smallest TDOA measurement error is 15.127 cm and the worst error is 27.230 cm, as was shown by the test results.

According to the requirement of the regional water resources demonstration system to clarify the total water consumption control index and water consumption standard, this paper studies and proposes the establishment of water consumption standard index, puts forward the analysis principle and method of water consumption standard index based on the combination of standard reference and typical investigation, and carries out the application research with Haining Economic Development Zone as an example, The research results provide technical support for regional implementation of water resources demonstration system and enterprise water saving evaluation.