The upgrade of offshore wind turbines is an effective method to reduce wind power costs, which can effectively disperse the cost of unit power and kilowatt hour power. The use of evaporative internal ...cooling technology can effectively improve the power density of the motor and reduce the manufacturing cost and maintenance cost of the wind turbine. At present, there are few research reports on the evaporative internal cooling technology of wind turbines. In this paper, according to the previous evaporative cooling experiment experience, the electromagnetic scheme of 5MW evaporative internal cooling wind turbine is designed specifically, and the evaporative cooling experiment is carried out by using the existing large test equipment, and a relatively complete design and experiment of evaporative internal cooling wind turbine is carried out. It provides important reference data for the engineering of evaporative internal cooling wind turbine.
Fine-Grained Joint Chinese Word Embedding Tian, Xiang; Cao, Xiaopeng; Wu, Yuze
Proceedings of the 2021 4th International Conference on Artificial Intelligence and Pattern Recognition, 2021 4th International Conference on Artificial Intelligence and Pattern Recognition,
09/2021
Conference Proceeding
Word vector research is one of the basic research in the field of natural language processing. The existing Chinese word embedding model does not make full use of the relationship between ...subcharacters that make up Chinese characters, nor does it fully consider the different contribution of subcharacters to semantics. In this paper, we propose a Fine-grained Joint Chinese word embedding model(FPWE). Firstly, Chinese characters are decomposed into fine-grained sub-characters with semantic information. Secondly, Bi-LSTM is used to establish the correlation between sub-characters of Chinese characters. At the same time, the attention mechanism is introduced to deal with the different semantic contributions between sub-characters, word information and sub-character information. Finally, we evaluate our model on the word similarity calculations and word reasoning tasks, the results showed that our model performance of this paper is better than that of the baseline model.
Short answer automatic scoring is a research hotspot of text semantic matching. Education text contains the multidisciplinary characteristics. Each discipline can be subdivided into a small field. ...Researchers use a large-scale and hyper-parametric deep learning model to deal with these text. This method results in difficult reproduction and high training costs. In this paper, we propose a Multi-model Dynamically Cooperation Semantic Matching (MMDCSM) algorithm which combines multiple models through rule collaboration. We use LCQMA dataset and Xiyou ASAG dataset to experiment MMDCSM algorithm. Xiyou ASAG dataset is created by Xi'an University of Posts and Telecommunication. The results show that MMDCSM algorithm can effectively improve the accuracy and reduce the complexity of related training in the short answer automatic scoring task.
Terrestrial and aerial bimodal vehicles have gained widespread attention due to their cross-domain maneuverability. Nevertheless, their bimodal dynamics significantly increase the complexity of ...motion planning and control, thus hindering robust and efficient autonomous navigation in unknown environments. To resolve this issue, we develop a model-based planning and control framework for terrestrial aerial bi-modal vehicles. This work begins by deriving a unified dynamic model and the corresponding differential flatness. Leveraging differential flatness, an optimization-based trajectory planner is proposed, which takes into account both solution quality and computational efficiency. Moreover, we design a tracking controller using nonlinear model predictive control based on the proposed unified dynamic model to achieve accurate trajectory tracking and smooth mode transition. We validate our framework through extensive benchmark comparisons and experiments, demonstrating its effectiveness in terms of planning quality and control performance.
In order to meet the higher demand of dynamic reactive power support is put forward in the UHV DC power transmission project, the new-generation synchronous condensers are applied in the UHV DC/AC. ...However, in order to provide bidirectional transient reactive power characteristics during AC and DC grid fault condition, especially to reduce the commutation failure phenomenon at the inverter station, there are great changes in the main body and excitation control system of the new-generation synchronous condensers compared with the same-capacity generators. Therefore, according to the requirement of reactive power in the grid and the requirements of safe for the new-generation synchronous condensers, the limiting model of excitation system for the new-generation synchronous condensers under low excitation and strong excitation conditions are established. Based on this, the closed loop transfer function of the excitation current is derived. According to the requirement of the excitation limit model, the analytical expressions of the transient reactive power of the new-generation synchronous condensers are obtained during the high and low voltage of the grid. Finally, the simulation model of the new-generation synchronous condensers access to UHV DC power grids are built based on the PSCAD software. The transient reactive support capability of the new-generation synchronous condensers under grid fault condition are verified.
As multiple nations aim to achieve carbon neutrality goals, photovoltaic (PV) generation has experienced significant growth. Nevertheless, this expansion has presented a few obstacles which must be ...addressed, for example, security of power terminals in distributed PV generation system. Due to their distributed nature, power terminals in the distributed PV generation system have become highly vulnerable to adversarial threats, rendering them easy targets for attacks. This paper aims to advance a novel approach for detecting attacks on power terminals in distributed PV generation system by employing side-channel technique that monitors the power consumption of the terminal and by utilizing deep neural networks for the classification of attack types. This approach has been demonstrated to be fast, cost-efficient and highly precise.
This letter presents a novel and retractable ring-shaped quadrotor called
Ring-Rotor that can adjust the vehicle's length and width simultaneously.
Unlike other morphing quadrotors with high platform ...complexity and poor
controllability, Ring-Rotor uses only one servo motor for morphing but reduces
the largest dimension of the vehicle by approximately 31.4\%. It can guarantee
passibility while flying through small spaces in its compact form and energy
saving in its standard form. Meanwhile, the vehicle breaks the cross
configuration of general quadrotors with four arms connected to the central
body and innovates a ring-shaped mechanical structure with spare central space.
Based on this, an ingenious whole-body aerial grasping and transportation
scheme is designed to carry various shapes of objects without the external
manipulator mechanism. Moreover, we exploit a nonlinear model predictive
control (NMPC) strategy that uses a time-variant physical parameter model to
adapt to the quadrotor morphology. Above mentioned applications are performed
in real-world experiments to demonstrate the system's high versatility.
We report electronic transport measurements on high quality floating zone grown Na(x)CoO2 and Na0.41CoO2·0.6H2O single crystals. We find an in-plane electronic scattering minimum near 11 K and a ...clear charge ordering at approximately 50 K. The electronic and magnetic properties in hydrated and nonhydrated Na0.41CoO2 samples are similar at higher temperature, but evolve in markedly different ways below ∼50 K, where a strong ferromagnetic tendency is observed in the hydrated sample. Model calculations show the relationship of this tendency to the structure of the Fermi surface. The results, particularly the clear differences between the hydrated and nonhydrated material show a substantially enhanced ferromagnetic tendency upon hydration. Implications for superconductivity are discussed.
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