Construction of trace element in coal of China Database Management System: based on WebGIS

The combination of geographic information system and mineral energy data management is helpful to promote the study of mineral energy and its ecological damage and environmental pollution caused by its development and utilization, which has important application value. The Trace Elements in Coal of China Database Management System (TECC) is established in this paper, applying the techniques of B/S three-layer structure, Oracle database, AJAX and WebGIS. TECC is the first database system which aims at managing the data of trace elements in coal in China. It includes data management and analysis module, document management module, trace elements in coal data maintenance module and authority management module. The data entry specification is put forward in the present study and the spatial data is included in TECC system. The system achieves the functions of data query, analysis, management, maintenance and map browsing, thematic map drawing as well as satellite video display, which lay the foundation for the analysis of large data of trace elements in coal. It is a practical platform for the acquisition, management, exchange and sharing of trace element research and geochemical research data of coal

Recent Advances in Multi-modal 3D Scene Understanding: A Comprehensive Survey and Evaluation

Multi-modal 3D scene understanding has gained considerable attention due to its wide applications in many areas, such as autonomous driving and human-computer interaction. Compared to conventional single-modal 3D understanding, introducing an additional modality not only elevates the richness and precision of scene interpretation but also ensures a more robust and resilient understanding. This becomes especially crucial in varied and challenging environments where solely relying on 3D data might be inadequate. While there has been a surge in the development of multi-modal 3D methods over past three years, especially those integrating multi-camera images (3D+2D) and textual descriptions (3D+language), a comprehensive and in-depth review is notably absent. In this article, we present a systematic survey of recent progress to bridge this gap. We begin by briefly introducing a background that formally defines various 3D multi-modal tasks and summarizes their inherent challenges. After that, we present a novel taxonomy that delivers a thorough categorization of existing methods according to modalities and tasks, exploring their respective strengths and limitations. Furthermore, comparative results of recent approaches on several benchmark datasets, together with insightful analysis, are offered. Finally, we discuss the unresolved issues and provide several potential avenues for future research

Energy Efficiency Optimization Design of a Forward-Swept Axial Flow Fan for Heat Pump

As one of the key components of the heat pump system, compared to that of a conventional axial fan, the blade tip area of a forward-swept axial fan is much larger than its blade root, which is the main noise source of the fan and also has an important influence on the fan efficiency. Enhancement of the aerodynamic performance and efficiency of a forward-swept axial fan was addressed by utilizing the Bezier function to parameterize the forward-swept curve on blade tops. In order to quickly select an agent model suitable for the project, an ES model was established by integration of the radial basis function model and the Kriging model. When NSGA-II was combined, multi-objective optimization was carried out with the flow rate and total pressure efficiency as optimization goals. Analysis of optimization results revealed that the optimized axial flow fan’s flow rate and total pressure efficiency were improved to some degree. At the design working point, the fan’s flow rate increased by 1.78 m³/min, while the total pressure efficiency increased by 3.0%. These results lay solid foundation for energy saving of the heat pump system

Vision-force-fused curriculum learning for robotic contact-rich assembly tasks

Contact-rich robotic manipulation tasks such as assembly are widely studied due to their close relevance with social and manufacturing industries. Although the task is highly related to vision and force, current methods lack a unified mechanism to effectively fuse the two sensors. We consider coordinating multimodality from perception to control and propose a vision-force curriculum policy learning scheme to effectively fuse the features and generate policy. Experiments in simulations indicate the priorities of our method, which could insert pegs with 0.1 mm clearance. Furthermore, the system is generalizable to various initial configurations and unseen shapes, and it can be robustly transferred from simulation to reality without fine-tuning, showing the effectiveness and generalization of our proposed method. The experiment videos and code will be available at https://sites.google.com/view/vf-assembly

Loss of microRNA-7a2 induces hypogonadotropic hypogonadism and infertility

MicroRNAs (miRNAs) are negative modulators of gene expression that fine-tune numerous biological processes. miRNA loss-of-function rarely results in highly penetrant phenotypes, but rather, influences cellular responses to physiologic and pathophysiologic stresses. Here, we have reported that a single member of the evolutionarily conserved miR-7 family, miR7a2, is essential for normal pituitary development and hypothalamic-pituitary-gonadal (HPG) function in adulthood. Genetic deletion of mir-7a2 causes infertility, with low levels of gonadotropic and sex steroid hormones, small testes or ovaries, impaired spermatogenesis, and lack of ovulation in male and female mice, respectively. We found that miR-7a2 is highly expressed in the pituitary, where it suppresses golgi glycoprotein 1 (GLG1) expression and downstream bone morphogenetic protein 4 (BMP4) signaling and also reduces expression of the prostaglandin F2a receptor negative regulator (PTGFRN), an inhibitor of prostaglandin signaling and follicle-stimulating hormone (FSH) and luteinizing hormone (LH) secretion. Our results reveal that miR-7a2 critically regulates sexual maturation and reproductive function by interconnecting miR-7 genomic circuits that regulate FSH and LH synthesis and secretion through their effects on pituitary prostaglandin and BMP4 signaling

Robust control strategy of VSC-HVDC systems based on feedback linearization and disturbance compensation method

The Voltage Source Converter based High Voltage Direct Current (VSC-HVDC) technology has become the development direction of new energy grid-connected, DC power transmission and island power supply technology in the future due to its superior characteristics. The effective and reliable control method is important to realize the stable operation of VSC-HVDC system during disturbances. However, the common adopted control scheme for VSC-HVDC system lacks of superior dynamic response when system suffers external disturbances. Although some relatively new control methods have been continuously proposed and applied to the VSC-HVDC system, such as no-beat control, fuzzy control, sliding mode control and repetitive control, etc., they usually depend on detailed and exact system model. This paper focuses on the feedback linearization and disturbance compensation methods in VSC-HVDC system. Firstly, the mathematical model of VSC-HVDC system in dq coordinate system with modeling errors and external disturbances is derived. Secondly, in order to improve the dynamic response and robustness of the control, the feedback linearization and disturbance compensation method is used and designed to realize the decoupling control of the VSC-HVDC system. Finally, the VSC-HVDC system with conventional control and the proposed control is compared and analyzed on the PSCAD/EMTDC simulation platform. The results show that the proposed controller based on feedback linearization and disturbance compensation principle has better dynamic performance and higher robustness of regulation performance

Developing the Dynamic Bus Lane Using a Moving Block Concept

Existing dynamic bus lanes (DBLs) typically use a fixed and long blocking space to guarantee bus priority, leading to a conflict between bus priority and traffic capacity. This study proposes an innovative approach in a connected-vehicle (CV) environment, called dynamic bus lane with moving block (DBLMB). The length of the moving block can be adjusted with the bus speed in real time, aiming to ensure bus priority with fewer road resources, thus improving traffic capacity. A three-lane cellular automata model is established to evaluate DBLMB in comparison with two other strategies, bus lane without priority and bus lane with intermittent priority (BLIP). First, the benefits of DBLMB over the established DBLs are analyzed qualitatively by the macroscopic fundamental diagram. Next, simulation experiments are conducted to compare the coordination between bus priority and capacity under different strategies. Then, the impact of DBLMB on microscopic traffic flow is investigated through evaluation indicators including lane density, lane speed, lane-changing frequency, and travel speed. Finally, the sensitivity of bus delay and traffic capacity to CV penetration is discussed. The results show that: (1) the capacity of a three-lane road adopting DBLMB strategy can be stabilized above 5200 passenger car units per hour (pcu/h) when the bus departure interval is higher than 60 s and the expected level of service is below B. (2) With 100%, 80%, 60%, 40%, and 20% of CV penetration, DBLMB improves the average capacity of the road by 523 pcu/h compared with BLIP, with only an incremental bus delay of 6.43 s per vehicle

Risk Factors of Non-small Cell Lung Cancer with Bone Metastasis after Therapy

Background and objective Lung cancer is the leading cause of cancer-related deaths, patients with non-small cell lung cancer (NSCLC) usually have distant metastases, such as bone metastasis, brain metastasis, and lung metastasis. The purpose of this study was to explore the risk factors for bone metastasis in NSCLC patients. Methods A total of 176 cases of NSCLC were selected from May 2009 to May 2011, and patients were divided into two groups, namely the bone metastasis group and non-bone metastasis group. The general clinicopathological data of the two groups and analyzing the independent risk factors of bone metastasis were compared. Results In the general clinicopathological data of NSCLC patients. The thrombus or not and tumor-node-metastasis (TNM) stage were closely related to the occurrence of bone metastasis, and were statistically significant (all P<0.01). Prothrombin time, activated partial thromboplastin time, Fibrinogen, thrombin time, blood platelet, D-Dimer and alkaline phosphatase have significantly difference between the two groups (all P<0.05). Logistic regression analysis showed that fibrinogen, activated partial thromboplast in time, alkaline phosphatase, T4 phase, N3 phase and d-dimer were independent risk factors for bone metastasis in NSCLC patients. Conclusion Fibrinogen, alkaline phosphatase, T3, N2 stage and D-Dimer is the independent risk factors of bone metastases in patients with NSCLC