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Addressing the challenge of low identification accuracy in traditional load identification methods based on the truncated singular value decomposition（TSVD）method，especially when the external load frequency approaches or reaches the natural frequency of the structure，the LSTM-CNN load identification model is proposed in this paper. This model combines the feature extraction capabilities of the convolutional neural network（CNN）with the long-term memory function of the long short-term memory network（LSTM）. The load identification method based on the LSTM-CNN model is then applied to research load time domain waveform identification on the GAR TEUR aircraft model. For model training and load identification，the response data and excitation data from the structure are corrected. The identification results are compared with the TSVD method，LSTM method，and DCNN method. Results show that the load identification method based on the LSTM-CNN model proves effective for sinusoidal load identification problems，especially under the natural frequency excitation of the structure. The method exhibits high identification accuracy and robust noise resistance capabilities.

In order to study the effect of graded loading rate on creep characteristics of anthracite, the effects of graded loading rate and stress level on instantaneous strain, creep strain and creep rate of coal samples were analyzed by triaxial creep tests of anthracite under four different graded loading rates. The results show that at the same stress level, the higher the graded loading rate is, the smaller the instantaneous strain is and the larger the creep strain is, but the increasing trend of creep strain gradually slows down; at the same loading rate, with the increase of the creep stress level, the instantaneous strain of coal samples shows an overall decreasing trend of rapidly decreasing-slowly decreasing-increasing, while the creep strain of coal samples shows an overall increasing trend of basically unchanged-slowly increasing-rapidly increasing; the change process of creep rate can be divided into three stages: rapid decay, slow decay and stability, at the same stress level, the higher the graded loading rate is, the higher the maximum creep rate is, and the faster the creep rate decays.

To realize real-time monitoring and short-term forecasting and forewarning of coalmine ventilation systems (CVS), in this paper, we first established a joint surface and underground CVS safety management system consisting of main ventilation fan, safety-partition linked passageways, and air-required locations. We then applied chaos theory to identify the air quantity and gas concentration of underground partition boundaries, and adopted a fixed data quantity, multi-step progressive, weighted first-order local-domain method to setup a chaos prediction model and a CVS safety forecasting and forewarning system formed by the normal change level, orange forewarning level, and red alarm level. We next conduct the on-field application of the system in a coalmine in Jining, Shandong, China. The results showed that (1) in the statistical scale of 5 min, the changes in both air quantity and gas concentration along CVS partition airflow boundaries were characteristic of chaos and could be used for short-term chaos prediction, and the latter was more chaotic than the former; (2) the setup chaos prediction model had a higher prediction precision and the established safety prediction system could not only predict the variation in CVS stability but also reflect the rationality of underground mining intensity. Thus, this CVS safety forecasting and forewarning system is of better application value. Keywords: Mine ventilation system, Safety partition, Reconstructed phase space, Maximum Lyapunov exponent, Chaos forecasting and forewarning

In this work, an all-fiber-based mode converter for generating orbital angular momentum (OAM) beams is proposed and numerically investigated. Its structure is constructed by cascading a mode selective coupler (MSC) and an inner elliptical cladding fiber (IECF). OAM modes refer to a combination of two orthogonal LPlm modes with a phase difference of ±π/2. By adjusting the parameters and controlling the splicing angle of MSC and IECF appropriately, higher-order OAM modes with topological charges of l = ±1, ±2, ±3 can be obtained with the injection of the fundamental mode LP01, resulting in a mode-conversion efficiency of almost 100%. This achievement may pave the way towards the realization of a compact, all-fiber, and high-efficiency device for increasing the transmission capacity and spectral efficiency in optical communication systems with OAM mode multiplexing.

A fungal isolate (ZZS4408) was obtained from a river water sample in Henan, China, and identified as a member of Neurospora brevispora, a rare species of Neurospora based on its morphological characteristics and ribosomal DNA internal transcribed spacer (rDNA-ITS) sequence. The temperatures suitable for growth of the isolate were 28-37°C with 31°C as the optimum. The growth rates of hyphal tips were 19.1-42.5 (av. 31.9) μm min-1 at 32°C. The pH suitable for vegetative growth ranged from 5 to 7, with pH 5.5 as the optimum. The heterodisaccharides (sucrose and lactose) and D-alanine were found to be most favorable for vegetative growth of the isolate, as carbon and nitrogen sources, respectively. The vegetative growth of the isolate was more significantly influenced by nitrogen sources compared to carbon sources. N. brevispora could be considered a desirable fungal species for morphodifferentiation studies due to its rapid growth rates under favorable conditions.

Ultrasonic vibration honing(UVH), a machine technology, has a lot of advantages. Lower grinding temperature is a significant character and is beneficial for both processing and workpiece surface. But the high temperature caused by big honing pressure becomes the main factor to produce workpiece heat damage in grinding zone. In various honing parameter combinations, the showing effect is different. Based on the thermodynamics classical theory, established the heat transfer equation for grinding zone, simplified the model and obtained the two-dimenssion temperature field expression for workpiece, then simulated the temperature changing trend in a variety of conditions. It is shown that themain temp is in a range of 700K to 1200K. In addition, the variation is huge for every parameter. The study provides a theoretical basis for deeply seeking reasonable machining parameter and obtaining better workpiece quality.