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Quantitative identification of the saline soil salinity content is a necessary precondition for the reasonable improvement and utilization of saline land, the article aimed at comparing the different quantitative analysis methods and achieving fast estimation of the saline soil salt content in the Yellow River Delta based on the visible-near infrared spectroscopy. Kenli County in Shandong Province was selected as the experimental area, firstly, the representative soil samples were selected, hyperspectral reflectance of the soil samples were measured in situ and transformed to the first deviation. Secondly the correlate spectra, the characteristic spectra and indices were firstly filtered using correlation analysis. Finally, the estimation models of soil salinity content were built using the multiple linear regression (MLR), back propagation neural network (BPNN) and support vector machine (SVM) respectively. The results indicated that the characteristic wave bands of soil salinity were 684 nm and 2058 nm. On the condition of the same input variables, the prediction precision of the SVM models was the highest, followed by the BPNN, the MLR was the lowest. The SVM model based on the first deviation of the reflectance at 684 and 2058nm had the highest precision, with the calibration R2 of 0.91 and RMSE as 0.11%, the validation R2 of 0.93, RMSE as 0.26% and RPD as 2.61, which had very good prediction accuracy of soil salt content, and was very stable and reliable. Different input variables had a great impact on the model accuracy, among of the MLR models, only the precision of the model based on characteristic spectral indices was slightly higher and could be used to estimate salt content, among of the BPNN and SVM models, the precision of the models based on characteristic spectra and indices was more high and stable significantly than the models on the correlate spectra. Therefore, for the three modeling methods of multiple linear regression, back propagation neural network and support vector machine, building the estimation model of saline soil salinity content based on characteristic spectra indices was effective.

View of the current ice-making machine for cooling system of the state of loosely designed in this paper under operating principle and structure and the cooling characteristics of a household ice-making machine,precise exposition of various refrigeration equipment`s design and calculation method, analysis of its selection ideas for the ice-making machine for cooling system designed to provide a important value of reference.

Nearly twenty years, freezing damage prevention of concrete construction in winter, construction methods of generalized integrated heat storage, the third generation of water-reducing agent (Poly carboxylic acid sodium), the theory of critical maturation degree, composite antifreeze, the key and matching technology of concrete construction under negative temperature and so on are all emerging constantly. Development progress of winter construction technology is promoted. All kinds of technology and economic about construction methods in winter are compared in this paper. The selection basis of concrete construction methods in winter is provided for different conditions.

Automatic particle counter is widely used in particle size analysis, fluid particle pollution degree and filtering properties testing. In this article, the test-bed of Zhejiang Universe Filter Product Qulity Test Center used in fuel filtration efficiency test is introduced. According to the domestic and foreign relevant test standard, this test-bed adopts particle counting and multi-pass method for experimenting of international general approval. And by using the test-bed, we can manage to test and analyse filtration efficiency and dust holding capacity of automotive fule filter.

To real-time monitor vehicle exhaust emission under daily running, this paper proposed a on-board measurement of diesel vehicle smoke intensity system based on GSM/GPRS and GPS, and concentrated on the design of hardware and software of the vehicle mounted terminal. This paper broke the traditional fixed-point way to sample exhaust data and could acquire data of different section, different vehicle types and different time.

For the vehicle emission pollution has become to be a serious problem, with the use of GPRS/GSM wireless communication technology the automobile exhaust emission information can be sent to the remote central server, realizing the purpose of remote monitoring management. This paper introduces the composition and working principle of this system which uses the three-layer structure of car-terminal, wireless network and PC monitoring center. And emphatically studies one kind of methods based on the generic TCP protocol, Socket, multiple threads technology and ASP.NET technology to realize the B/S mode monitoring system communication.

As the development of carbon diocide sensors and communication technology, the method for monitoring the concentration of carbon dioxide is more and more advanced, especially the traditonal methods have the disadvantage of the low accuracy and inconvenience on use. This paper puts forward a wireless sensor networks based on TC35 module and the method of the signal transmitting. Through the application of wireless technology, the MCU could send the carbon diocide concentration data from the carbon diocide sensor which is based on the NDIR technology to the process module, and the system could achieve the distant measurement of the carbon diocide displayed on the LED. Comparing with wire monitor system, wireless monitor system omits linking lines and it has good application prospect.