Search

This paper describes how to detect energy consumption automatically, especially based on infrared images. We find a method of combining those pictures efficiently. In order to make a direct conclusion, we make a bar of temperature distribution.

After excluding the usual device error, environmental error caused by electromagnetic interference persists in the acquisition system of heating flux of building envelope. This error makes the system instability and causes relatively large deviations of heat flux data, affecting building energy conservation measurement. To counter the problem of error in the data acquisition system, a new software filtering algorithm is put forward. The algorithm combines the idea of the mean and median filtering method, and specific algorithm formula and algorithm steps are given in this paper. Experimental results showed that the algorithm effectively improved the accuracy of data collection. For example, when I input 1mV into system from the sensor, average error of heat flux was decreased from 5.2% to 0.4%, and the maximum error was less than 2%.

A data communication method applicable to building detection industry based on the wireless sensor network (WSN) is designed and implemented in this paper, in which the cause of data loss is analyzed in accordance with the characteristics of wireless sensor network and that of building detection industry. Besides, relevant data storage protocol, staggered transmission protocol, and real-time data replenish protocol are formulated to solve the problem above and improve the reliability and integrity of data.

This paper analyzed the advantages and disadvantages of existing heat flux sensor calibration methods, proposed a calibration method of thermal heat flux sensor based on wireless sensor networks. Experimental results showed that the detection error was reduced from 6% to 2% after calibration. The proposed method has many advantages, such as short calibration time, accurate results, easy installation as well as batching calibration. In a word, this method is available to calibrate heat flux sensors and will have an important significance for accurate measurement of heat flux.

It is of great significance and value to predict the roll of two ships, especially when one is replenishing for the other or in some other conditions. Autoregressive time series analysis method (AR) with Recursive least squares (RLS) theory is the mainstream currently and the effectiveness for the prediction of the motion attitudes have been fully validated. However, there are some differences between the prediction for the motion of two vessels and for that of one. The hydrodynamic interactions between two ships should be taken into consideration and be reflected in the application of the method. In order to solve this issue, this work firstly proposed a double ships autoregressive (DAR) method, which can determine the orders and the parameters of model in real-time with consideration of the interference between two ships and the DAR method was applied to forecast the roll motion between two ships. The simulative results of DAR method show the validity and veracity compared to real value and the advancement compared to the autoregressive (AR) method for single ship motion prediction.

Neutron velocity selector is widely used on neutron scattering instruments as key component. To calibrate it (wavelength and wavelength-resolution-rate measurement), it is necessary to design calibration instrument and develop calibration technique. Based on small angle neutron scattering instrument (SANS) at China Advanced Research Reactor (CARR), instrument structure was designed and instrument parameters were determined. Count loss influence on measurement of wavelength resolution rate (WRR) was studied for the first time. Measurement error of WRR is decided by product of dead time and Gauss peak count rate (GPCR) and increases with increasing GPCR for the same dead time. In order to ensure WRR measurement error less than 0.9%, upper limits of GPCR for detector adjoining chopper and detector far away from chopper are less than 10000[s-1] and 2500[s-1] respectively. According to upper limits of GPCR, floor limit of total measurement time for each spectrum is calculated to be 6.66 minutes.

In this paper, the pulse-induced acoustic sound in laser cutting is collected, and the data processing is performed with wavelet denoising and time-frequncy analyzing. The impact of laser processing parameters on the acoustic signal is discussed; and further analysis of the effect of cutting speed is conducted. The corresponding relationship between the best velocity and the maximum time-frequency energy density is got; also the plan of adaptive control in laser cutting is designed. The results in this paper can provide important parameters for adaptive control of laser cutting.

To calculate difference scheme’s accuracy of differential equation, the normal way is using Taylor format. This paper utilizes tectonic process of differential format to calculate truncation error and gets the accuracy. Compared with the traditional way, not only reduces the amount of calculation, but also calculates the accuracy more quickly and accurately for high-order equations.