Abstract A huge amount of stock reviews occurred on the Internet due to its rapid development, therefore, the stock reviews sentiment analysis has profound significance for the study of the financial market. Due to the lack of a large amount of labeled data, the accuracy of existing sentiment analysis of Chinese stock reviews remains to be further improved. In this paper, a sentiment analysis algorithm for Chinese stock reviews based on BERT is proposed and it improves the accuracy of sentiment classification. The algorithm uses BERT pre-training language model to perform representation of stock reviews on the sentence level, and then input the obtained feature vector into the classifier layer for classification. In the experiments, we show our method has nearly 8% and 9% improvement than TextCNN and TextRNN in F1, respectively. Our model can obtain the best results via fine-tuning which is proved to be effective in Chinese stock review sentiment analysis.
TEB (Timed Elastic Band) can efficiently generates optimal trajectories that match the motion characteristics of car-like robots. However, the quality of the generated trajectories is often unstable, and they sometimes violate boundary conditions. Therefore, this paper proposes a fuzzy logic control-TEB algorithm (FLC-TEB). This method adds smoothness and jerk objectives to make the trajectory generated by TEB smoother and the control more stable. Building on this, a fuzzy controller is proposed based on the kinematic constraints of car-like robots. It uses the narrowness and complexity of trajectory turns as inputs to dynamically adjust the weights of TEB's internal objectives. The results of real car-like robot tests show that compared to the classical TEB, FLC-TEB increased trajectory time by 16% but reduced trajectory length by 16%; The trajectory smoothness was significantly improved, the change in the turning angle on the trajectory was reduced by 39%, the smoothness of the linear velocity increased by 71%, and the smoothness of the angular velocity increased by 38%, with no reverse movement occurring. This indicates that when planning trajectories for car-like mobile robots, FLC-TEB provides more stable and smoother trajectories compared to the classical TEB.
Known to all,phase shifting interferometry is a well accurate technique and is applied in many fields.Vibration is one of the main error sources in the phase shifting interferometry.A number of methods have been put forward by the researchers all over the world which are classified into two categories,the active and passive vibration resistant techniques.The first is that the system test vibration and compensate it and the latter means to reduce the system's sensitivity of vibration by many techno-method.And the development of them is presented.In the end,the work on these two methods by the author's group is introduced.
Objective Dexmedetomidine (Dex) is a highly selective a2 adrenoceptor agonist that reduces blood pressure and heart rate. However, its ability to provide stable hemodynamics and a clinically significant reduction in blood loss in spine surgery is still a matter of debate. This study aimed to investigate the effects of Dex on intraoperative hemodynamics and blood loss in patients undergoing spine surgery. Methods The Web of Science, MEDLINE, EMBASE, and The Cochrane Library were searched up to February 2023 for randomized controlled trials (RCTs) including patients undergoing spine surgeries under general anaesthesia and comparing Dex and saline. A fixed- or random-effect model was used depending on heterogeneity. Results Twenty-one RCTs, including 1388 patients, were identified. Dex added the overall risk of intraoperative hypotension (odds ratio [OR]: 2.11; 95% confidence interval [CI]: 1.24 - 3.58; P=0.006) and bradycardia (OR: 2.48; 95%CI: 1.57 - 3.93; P=0.0001). The use of a loading dose of Dex led to significantly increased risks of intraoperative hypotension (OR: 2.00; 95%CI: 1.06 - 3.79; P=0.03) and bradycardia (OR: 2.28; 95%CI: 1.42 - 3.66; P=0.0007). For patients receiving total intravenous anesthesia, there was an increased risk of hypotension (OR: 2.90; 95%CI: 1.24 - 6.82; P=0.01) and bradycardia (OR: 2.66; 95%CI: 1.53 - 4.61; P=0. 0005). For patients in the inhalation anesthesia group, only an increased risk of bradycardia (OR: 4.95; 95%CI: 1.41 - 17.37; P=0.01) was observed. No significant increase in the risk of hypotension and bradycardia was found in the combined intravenous-inhalation anesthesia group. The incidence of severe hypotension (OR: 2.57; 95%CI: 1.05 - 6.32; P=0.04), but not mild hypotension, was increased. Both mild (OR: 2.55; 95%CI: 1.06 - 6.15; P=0.04) and severe (OR: 2.45; 95%CI: 1.43 - 4.20; P=0.001) bradycardia were associated with a higher risk. The overall analyses did not reveal significant reduction in intraoperative blood loss. However, a significant decrease in blood loss was observed in total inhalation anesthesia subgroup (mean difference [MD]: -82.97; 95%CI: -109.04 - -56.90; P<0.001). Conclusions Dex increases the risk of intraoperative hypotension and bradycardia in major spine surgery. The administration of a loading dose of Dex and the utilization of various anesthesia maintenance methods may potentially impact hemodynamic stability and intraoperative blood loss; however, further high-quality studies are warranted to confirm these findings.
A near infrared reflective shearing point diffraction interferometer (NIRSPDI) is designed for large-aperture dynamic wave-front measurement. The PDI is integrated on the small substrate with properly designed thin film. The wave-front under test is reflected by the front and rear surfaces of the substrate respectively to generate an interferogram with high linear-carrier frequency, which is used to reconstruct the wave-front by means of the Fourier transform algorithm. In this article, the system error and the major parameters of NIRSPDI are discussed. In addition, we give an effective method to adjust NIRSPDI for fast measurement. Experimentally NIRSPDI was calibrated by a standard spherical surface and then it was applied to the dynamic wave-front with a diameter of 400mm. The measured results show the error of whole system which verifies that the proposed NIRSPDI is a powerful tool for large-aperture dynamic wave-front measurement.