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In the process of coal-mine production, the self-ignition of left coal in goaf area has always been major disasters, and spawns amount of economic loss. As a consequence, it is necessary and essential to monitor the self-ignition of left coal in goaf. In consideration of the complex and poor environment of the goaf area, this thesis adopts ZigBee wireless sensor network instead of traditional fixed cable sensor network to monitor the self-ignition of coal goaf area. It has the advantages of wild covering, convenient layout and easy adapting to environment. In addition, counting on the revised routing algorithm, the whole wireless sensor network has obvious advantages of its network performance and low consumption, which makes the whole system monitor the self-ignition of left coal steadily and permanently.

Based on the digital serial communication, E1 and Ethernet port circuits connecting the electronic equipment on ships, characterizations of the digital signals transmitted through the circuits are analyzed. The situations when the EMI generated by the digital systems causing pollution to the grounding system and the grounding voltages coupled to the signal-transmitting circuits are simulated. Furthermore, the influence of the equivalent impedance of the main and branch grounding cables on the grounding performance are analyzed quantitatively. Therefore, the grounding demand is obtained. Finally, some anti-interference measures so as to improve the grounding performance are proposed.

The mechanism of cable crosstalk involving what and how does the factors affect the level of crosstalk is introduced in detail. A transmission line model for predicting crosstalk between power cable and the other wires nearby with common reference ground based on multiconductor transmission theory (MTL) is developed. Crosstalk among circuit configurations when the victim cables with load terminations are different types is analyzed and simulated. Models where the types of the victim lines are shielded coaxial cable, shielded twisted pair and unshielded twisted pair are simulated. It is found that the shielding can provide an attenuation of about 50dB than the unshielded cables. In addition, the condition of multi-cable coupling is simulated and some thoughts are brought out to inspire more detailed study. Finally, some measures are suggested to suppress the crosstalk between cables according to the two-type of coupling mechanism (inductive coupling and capacitive coupling).

A simple method for synthesis of nanoselenium using oyster polysaccharides as soft template was investigated. The uniform stable selenium polysaccharides were obtained under the condition of reaction temperature 40°C, reaction time 3 h-5 h, the content of oyster polysaccharides 400mg/L and the content of sodium selenite 1mM. The size distribution and morphology of the product were confirmed by scanning electronic microscopy (SEM) and tansmission electronic microscope (TEM). The antioxidant activity of nanoselenium polysaccharides were studied in vitro. The results showed that nanoselenium polysaccharide is an effective hydroxyl radical and DPPH radical scavenger.

With the development of construction tissue engineered cornea by using biomaterials and seed cells,how to measurement transparence of tissue engineered cornea need to be solved. Purpose of the paper is bringing forward a new method to measurement transparence of tissue engineered cornea. According to the definition of corneal transparence, a beam of light is divided into equal two beams of light by spectroscope. In which a beam of light pass through cornea. Ratio of light energy flow that light passed cornea and the other one is calculated. The usual optical and measuring instruments were used, such as sensors for illumination and Data acquisition (DAQ) card. The real-time measuring device for corneal transparence is designed and implemented. The method and device are effective to real-time measurement of tissue engineered cornea transparence through the elements analysis and experiment.

Temperature is an important parameter representing the motor operating conditions. Temperature monitoring data are time series data, which have strong correlations in time. From the perspective of mathematical statistics, these correlations of time series were analyzed using EViews6.0 software in this paper. Through the establishment of ARIMA model, the motor shell temperature time series was predicted.The final prediction model is ARIMA(1,1,2). Simulation shows that ARIMA model has high predict precision and can be used to predict the temperature of motor shell, which can help to detect equipment failures, avoiding the losses caused by motor faults.

The design of four degrees of freedom pneumatic conveyance manipulator based on PLC is introduced in the paper. The work task of the manipulator was briefly introduced. The structural design, work cycle, pneumatic control circuit design and PLC control system design are introduced in detail. The manipulator has the advantages of simple in design, stable and reliable act,research and development in low-cost. The design is to provide a reference for other design of economic type manipulators.

Based on the development practice of the pump performance test bed for the agricultural sprayer, a new program is proposed to cover the integrated mechanical structure of the pump performance test bed. Analysis was given to the various performance parameters of the pump test with regard to their testing methods, and specific methods of work performance test and inhalation performance test were also discussed to explore the test results. Finally, the issues that need to be focused were raised on the design and manufacture of pump performance test for the sprayer.

This paper introduces the hydraulic control system design for the change-wheel garage of Chongqing light rails through analysis of three-stage cylinder synchronization circuit for lifting bodies, and optimizing the design of the slewing mechanism with respect to the hydraulic servo control system of digital cylinder. The results improved the smoothness in the process of changing wheel lifting and the rotary accuracy of the rotary mechanism. Design on the PLC control system of the system is also included as part of this paper.

Aiming at the complicated situation of artificial testing function materials, a set of automatic test system based on Agilent E4980A is developed. In the control software edited by Visual Basic 6.0, the test conditions (temperature, frequency, voltage, etc.) are pre-set, and the system automatically controls the temperature of the temperature control box through PID algorithm, achieving the real-time test voltage and frequency of Agilent E4980A. The card shows the readings on the test results of a plurality of functional materials at various stages of temperature conditions , automatically completing the storage and analysis of electrical parameters. The system is able to achieve the automatic control of the temperature control box and Agilent E4980A, presenting the comparative benefits including the function of this system being more comprehensive, more convenience in operation, and higher degree of automation advantages . It can be a good method and reference resource available for the development of such test system.

This paper discusses the hottest topics which are about the global thermal environmental problem. Our group did some work in urban heat environment in Wuhan of China. Wuhan is a typical summer-hot- winter-cold city where the phenomenon of urban heat island effect is very strong. In order to find out the heat states of downtown and suburb, we carried out a field moving measurement in the summer of 2011. Two routes (according to the main wind directions) and 12 periods (the typical periods of heat island effect) were chosen by us for this experiment. As a result, we collected a series of data of temperature-humidity index, radiation temperature and wind velocity, made a good deal of graphs by data analysis and reduction. Finally we found several phenomena about urban heat environment, such as different positions of the knee points (inflexion) of the temperature at different time; the intensity of heat island effect from morning to evening. We have gotten some temperature scales about heat island effect in Wuhan. This conclusion provides a quantitative indicator for our urban renewal and redevelopment.