Search

There is a situation that the personnel in the office building are not concentrated and scattered, and some personnel will not always work at the workstation, and the creation of local comfort at the unmanned workstation will only cause great waste, so it is necessary to create an environment with uneven distribution of indoor parameters. In view of this situation, we simulate two working conditions: uniform and inconsistent airflow provision within the office space. analyze the comfort of these two working conditions in the office room, discuss the unevenness and energy efficiency of the ventilation openings above and near personnel in the office room. The simulation results show that creating non-uniform indoor air supply can greatly save energy.

An arc fault on the DC side of the photovoltaic system is a potential safety hazard and is difficult to detect due to the complexity of photovoltaic systems. The detection method of series arc fault in photovoltaic systems is investigated here. The DC arc fault test platform for a photovoltaic system is established to collect the current signal under normal and fault conditions. In this study, the time domain characteristics, frequency domain characteristics, and time-frequency domain characteristics are compared by analysing the current data from the photovoltaic system in before and after fault states: corresponding feature vectors are used to construct the arc fault feature space of the system, and according to the position of the current signal in the feature space the fault is detected, so as to realise effective arc fault feature information. Then the method of establishing the arc fault feature space is introduced and key parameters of the feature space are determined. Finally, the anti-interference ability of arc fault feature space detection is verified. The results showed that the detection method is both feasible and accurate.

The electric fire-exchanging operation is basically used to implement operation such as Wire stripping, drainage wire through the fastening wire clip, clamp bolt fastening, etc. Manual operation is time-consuming and laborious and has very high safety risks, so the automatic electrified ignition robot emerges as The Times require; The automatic operation method should accurately identify the position of wire and drainage line, so as to guide the robot to move and carry out the corresponding operation. Based on this, an intelligent binocular vision guidance method is proposed in this paper. The image data in the working space is collected by the binocular camera in real time, the wire is identified by the image segmentation technology, the wire is separated from the background, and the spatial pose of the wire is solved by the PNP and binocular stereo vision technology. Through YOLOV5 target detection, the position identification and positioning of the thread and clamp of the drainage line are realized, and the automatic fire ignition operation is finally guided by the manipulator. Experiments show that this method has the advantages of high accuracy, good stability and fast speed.

In order to research the effect of eye and neck rotational velocity on tracking accuracy in the process of target tracking of humanoid vision system, an optimal method of angle decomposition was be proposed based on the Jacobi matrix. By establishing mathematical model, the relationship between rotational angular velocity and decomposition angle is proposed. Through simulation and physical experiments, the relationship between angle of decomposition and rotational angular velocity is approximately linear. Compared with the equalization method, with the increase of angle and angular velocity, the time efficiency of method proposed in this paper increases. The work in this article provides basis for control scheme of target tracking for humanoid vision system.

In applied cryptography, RSA is a typical asymmetric algorithm, which is used in electronic transaction and many other security scenarios. RSA needs to generate large random primes. Currently, primality test mostly depends on probabilistic algorithms, such as the Miller-Rabin primality testing algorithm. In 2002, Agrawal et al. published the Agrawal–Kayal–Saxena (AKS) primality testing algorithm, which is the first generic, polynomial, deterministic and non-hypothetical algorithm for primality test. This paper proves the necessary and sufficient condition for AKS primality test. An improved AKS algorithm is proposed using Fermat’s Little Theorem. The improved algorithm becomes an enhanced Miller-Rabin probabilistic algorithm, which can generate primes as fast as the Miller-Rabin algorithm does.