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A measurement and analysis system is designed base on the requirement of digital upgrade to the KY231 Material strain tester. This system is made up of two parts :The analyze system based on the LABWINDOWS and the measurement system based on STM8S207. The physical quantities (such as stress, pressure, deformation, etc.) of the metal specimen are acquired, displayed and analyzed digitally in this system, meanwhile the experimental data and curves can be stored in the systerm and compared to the historical data saved in the previous files. Because the USB interface is too complex to the MCU systerm form the aspart of the programming and circuit design, the PL2303 is used to simulate USB interface as virtual RS232 for the communication between the measurement system and the analyze system.

This dissertation is centered about the research on the quartz-tube roasting lighter for electric heater by the simulative test methods. The experiments are carried out and accomplished in a large space laboratory. It turns out that the burning possibility are directly related to three aspects, including the power of electric heating, the distance between the lighter and electric heating, and, most importantly,the surrounding combustible condition. When the lighter is heated by electric heating and get blasted, combustible tend to be caught fire instantly if it is near to the lighter and the cause of fire, vice versa.

When fire breaks out, the gas composition and concentration as well as smoke concentration of burning part vary from those in normal environment. The gas and smoke absorbed during solidification of short circuited melted mark occurred in such environment will certainly have an effect on grain shape, grain size, holes distribution and impurity element distribution of organization of melted mark. The gas in the environment has a certain influence on the organization of short circuited melted mark, but the influence is smaller than that of smoke. The reason may be that the gas is mingled with certain amount of tiny smoke particles inevitably which play a role in the solidification of melted mark. Compared with short-circuit samples in normal atmosphere, carbon content of short-circuit samples increases and oxygen content decreases in the environment of smoke.

Fire scene investigation on fire caused by the wall socket,extracted the copper bead and aluminum wire material evidence,observe and analysis,include the macro analysis and metallographic analysis, and then confirmed the reason.Through the identification of the extracted fire material evidence,macro features are all electric heated,the metallographic analysis to determine the nature of the melted marks respectively for primary short circuit melted marks and over load melted marks and short circuit spatter melted mark. These three kinds of trace is in line when the electrical fault occurred formed, and a primary short circuit melted marks provides the most direct strong scientific basis for the cognizance of the fire,and determined the fires is caused by the faulted wall socket.

The Sampling flow will be decreased because the permeability weakness of filterable membrane after the dust sampler working for a period of time. It seriously affects the accuracy of measurement, so we should keep the dust sampler working under the constant gas flow. The stable, rapidness and accuracy constant sampling can be achieved based on the application of fuzzy-PID algorithm and the adoption of PWM technique. It has carried on design to the dust sampler control system from selecting the hardware and designing the software to data processing and errors analysis, and discussing the preferable performance of the dust sample control system.

The safe current carrying capacity of iron wire is far less than copper wires. In the simulation experiments, use iron wire replace copper wire and use welding machine as electric equipment, even the flaming. Normal operating electric homework, the whole iron wire overheat and cause carbonization of insulation layer and even set on fire because of line’s overload, and lead to short circuit between wire. Extract fire material evidence, observe and analysis. Summed up the microstructure characteristics of the sample. Apparent characteristics of short circuit melting mark organization is:wire matrix is widmanstatten structure and ferrite, the transition region is mainly widmanstatten structure; overload melted mark organization is mainly cast structure, there was more casting .

Nowadays, technology rapid development, the living standard of people also is rising, household devices gradually to the trend of electrification development, in the meantime, the fire also increase annually in caused by electrical equipment. The solar energy water heater used more widely, because the product quality, installation and improper use fire in the number of rising sharply. Among them, caused by electric heating cable fault accounts for a bigger chunk of fire, so the identification of electric heating cable fire are particularly important. We can made comprehensive Analysis on electric heating cable trace utilize the technical means of macroscopical method and metallographic method etc., judge its melting nature, can provide strong technical support for fire investigation.

The methods of work this identification system is that distill wheel speed characteristics to standard signal then stored in the system. When the first anti-lock loop begin to input the initial velocity to identification model then extract theoretical value of the system and input the actual speed then calculate the similar with theoretical speed. The maximum similarity value is the identification when the pavement is true. After that every cycle identifies monitoring (again identify based on new data) that is establishing state observer. Though it is inaccurate due to various interference identifications or when the adhesion coefficient of pavement has changed ABS will determine quickly make the work more reasonable. Choose normal distribution and exponential distribution of statistical principles to identify the pavement and modify the identification model with gamma membership function. Tire model choose H.B.Pacejka model suitable for programming. It will use Gauss numerical integration and rational interpolation to increase the timeliness of identification. The method this paper described is suitable for the identification of low road.

Electrical wiring is the main fireorigin on electrical fire, and aluminum wire laying lines used more fire hazard. The melting mark formed in process of fire is the important material evidence to analysis the cause, but the aluminum wire melting mark organization feature is also different in different solidification conditions, therefore, to identify the mark characteristics formaed in different environment conditions has become a important task of fire evidence identification. Prepared fire sample melting by the means of simulation test, and observed to analysis the experimental sample, then summarizes the influence of solidification environment on microstructure characteristics of aluminum wire trace sample. Through the analysis found that, because of the influence of subcooled temperature, make the most of the organization of melt mark cooled in the air have oversize equiaxial crystal organization, almost no holes; and the dip in water cooling of melting mark is formed in larger subcooling, so the organization have more than a small columnar crystal and cellular crystal, and have more small holes exist. These features of aluminum conductor mark can provide strong technical support for fire investigation.

An experimental investigation was conducted on 4100 engine to study the influences of different percentages of methanol in DME/diesel blended fuel on combustion and emission performance. The result indicates that a certain amount of methanol in DME/diesel blended fuel can reduce production cost, improve the engine's power performance at the same time, but when the methanol percentage is increased (over 2%), the power performance will decrease. With the increase of methanol proportions, the maximum cylinder pressure is slightly increased, the peak of heat-release curves are declined and delayed, the cylinder temperature is decreased, the ignition timings are delayed and the combustion duration is shortened. In addition, NOx emissions were further reduced, but the HC emission, the CO emission and the soot emission has a little rise.

In order to meet the need of identifying obstacles and navigating for the Coal Mine Detection Robot which is used to rescue life and detect environment from coal mine disaster, binocular stereo vision is researched and 3D model of objects around the robot is reconstructed by means of two cameras of visual system built in the robot. The two cameras are calibrated and two projection matrices of them are obtained. Then, two images of the same scene are obtained by the two cameras. The matching points of two-dimensional coordinate are got through Harris corner extraction and stereo matching. According to the principle of binocular vision, equations are obtained and solved by least square method, which can calculated the discrete points of 3D coordinate.

A variable-grain strategy is proposed to solve the complicated problem of optimization design on high-speed transmission helical gears with multiple objectives and restrictions. Based on the theory of gear meshing noise and the superiority criteria, a multi-objective evaluation index system is brought forward which gives consideration to the increase of the contact ratio and the decrease of the noise generated by the slide ratio of the tooth flank meshing and the mutation of friction torque, and then the variable-grain multi-objective optimization models of high-speed helical gears are established. The coarse-grained model is utilized in the early design to efficiently determine the direction to the optimal solution. Then the grain is refined and the fine-grained model can be utilized to acquire the optimal result.

In view of the characteristics of the low-noise and high-strength of auto gears, this paper proposes a new method of optimization of fine-pitch tooth profile. Based on the constant gear-pair parameter values of transmission ratio, modulus, pressure angle, the method takes the optimal contact ratio as design object, sets up the constraint conditions such as noise limit index, non-interference, non-undercutting, and non-sharpened in the tip, and optimizes the addendum coefficient and coefficient so as to increase the contact ratio. In addition, this paper makes a finite element strength analysis on the design result, and the result shows that the new method can not only reduces noise but also improves gear strength of fine-pitch gear.

With the ESE module of FIRE software, this paper establishes the diesel engine model of 4100, and verifies the correctness with the test result. Based on this, the paper carries on a simulation on three high proportions of DME-diesel D65, D75 and D85, and makes a contract with diesel on the mean pressure, mean temperature, mass fraction, accumulated heat release, as well as the mass fraction of NOx and soot. The result shows that the higher proportional, the lower mean pressure in-cylinder. Also the result shows that NOx growth will come to a “freezing period” when it comes to a certain temperature, while soot growth is growing first and oxygenated later, and with the increase of DME proportion, NOx grows later and its mass fraction is lower. Besides, the mass fractions of soot of three kinds of mixed fuels are far below diesel’s, D85’s is the lowest.