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The concentrations of heavy metals (Cr, Cu, Ni, Pb and Mn) were determined using flame atomic absorption spectrophotometer after digested with four acids. The samples were collected from seven kinds of different functional areas in Taiyuan, China. The concentration of the heavy metals were found in Taiyuan is higher than the soil background values in Shanxi Province, which appeared different levels of accumulation. High concentrations of Cr, Ni, Mn were found in the samples from industrial area and Cu was noted from economic development area. The correlational analysis and principle component analysis showed that the heavy metals of surface dust in Taiyuan were mainly influenced by industrial activities.

Traditional random forest algorithm is difficult to achieve very good effect for the classification of small sample data set. Because in the process of repeated random selection, selection sample is little, resulting in trees with very small degree of difference, which floods right decisions, makes bigger generalization error of the model, and the predict rate is reduced. For the sample size of sepsis cases data, this paper adopts for parameters used in random forest modeling interval division choice; divide feature interval into high correlation and uncertain correlation intervals; select data from two intervals respectively for modeling. Eventually reduce model generalization error, and improve accuracy of prediction.

The pulse wave is a very useful physiological signal which can reveal the information of human organs. D-peak change is an important change of pulse. To study the spectrum of the D-peak changed pulse wave quantitatively and get the statistics result of such kind of change, a new algorithm was proposed and a kind of processing software was designed and implemented. The software was tested by more than 200 person-times PPG pulse waves and showed good performance.

This paper describes the design ideas of intelligent management system for open labs based on wireless transmission. The student legal identity authentication is completed using IC cards and the equipments power supply is controlled using wireless digital transceiver chip nRF401.The system hardware is simple, no complex wiring, easy to use. It can be used in any laboratory of electronic equipment, has the very good practicability and wide application prospects.

This project mainly studies the structure composition and the working principle of the seat vibration system of the roller . On this basis, dynamic equations are obtained according to the stress analysis of the simplified system of the seat vibration system of the roller, and then with the simulink module of MATLAB software, a simulation model is established as to the driver's seat system.Through the model simulation, the roller’s vibration of the the driver seat system is analysed,then based on the analysis, the optimization design can be done. Finally, through the research of this topic, the ride comfort of roller is been improved.

The photonic crystal fiber was applied in high-power laser gain medium, because of its flexible and optical controllability and special structure, which can overcome the design flaws of common optical fibers effectively. This paper studied the Yb3+ doping double-clad photonic crystal fiber. Through the theoretical analysis and numerical simulation, it optimized the structure design, drew the high doping concentration and double-clad fiber samples, analyzed the absorption and fluorescence spectra of fiber core material, and tested the optical fiber spectrum features, which can improve the performance of high power fiber laser.

In this paper, a real-time monitoring system of all-weather fatigue driving which is based on DSP (TMS320DM643) is introduced. The method of regional area combining the skin color model, can quickly locate the drivers face. The paper also presents the judgment of eye state, the fetch of fatigue parameters (PERCLOS, ECT and EBF), and the general method for the determination of fatigue degree. The system has very strong using value, and practical significance.

The traditional technology in production of doped fiber has disadvantage of low doping concentration, uneven distribution of refractive index, being difficult to produce large core diameter etc. This paper according to the demand of high-power ytterbium doped photonic crystal fiber laser, makes a research of producing methods to large mode area, Yb3+ doped photonic crystal fiber. Anhydrous doping nanometer particles are obtained by solution doping method, using plasma non-chemical vapor deposition method produce fiber core material, large mode area, ytterbium doped fiber sample is made and laser properties experiments has been done. By experiments it is found that at 2cm pre-end of the sample has violet light, Yb3+ doped fiber has laser operation.

Small town is the breakthrough point to quicken urbanization. This paper analyses many problems during the small towns construction in the less developed areas such as conservative ideas, the low level of urban planning, lack of economic dynamism and the negligence of cultural advantage. The characteristic innovations on concept, planning, economy, culture and architecture are put forward, for developing its distinct local characters and advantages.

On the analysis of worldwide situation of river ecological restoration, this paper takes the Jialu River in Zhengzhou city as an example, carries out the study on ecological improvement of traditional river projects in six aspects, such as the arrangement of watercourse plane and section morphology, the design of ecological revetment engineering course, the engineering measures to create artificial imitation of natural habitats, the shallow surface flow unit engineering design of wetland and artificial wetland treatment, the protection and combing with floodplain woodland and the plants disposition of waterfront area. The results may provide the reference for the ecological restoration technology.

Quantitative analysis of soft soil microstructure in unloading levels are made by using scanning electron microscope (SEM) images, IPP and PS of image technology ,which includes image segmentation, pore size measuring and counting, three dimensional simulation of soft soil microstructure, etc. The results indicate that, with the increase of unloading grade, pore number and area of big aperture are in a sharp increase, the corresponding porosity also in ascension, so the deformation of the soil is mainly due to the change of pore; compared with the apparent 3d images of soil under the transverse profile in unloading levels. The results also indicate that, with the increase of unloading grade, pore area of cross section are in a increase.

The hot-dip galvanizing coating can promote the anti-corrosion performance of the bolts in outdoor steel structure engineering. But the anti-corrosion performance cannot match that of the steel due to the centrifugal process. In this paper, the anti-corrosion performance of four kinds of bolts obtained from different company was researched by the neutral salt spray test method. The results show that the anti-corrosion performance of the all four bolts was unsatisfactory. The reasons were studied through testing the thickness of the coating, coating uniformity, surface morphology and elemental composition. The results show that the causes are the lower thickness of the hot-dip coatings, too much defects on the surface of the coatings and the elemental composition impurity.

It will cause the drop of the acceleration performance and driving comfort if the continuously variable transmission shift too quickly. So Aiming at the shifting problem of continuously variable transmission system, This thesis put forward the method to control shift speed of the continuously variable transmission based on driving intention. By the dynamics analysis of continuously variable transmission system, it does a research on the influence on the motor automobiles acceleration performance and driving comfort, when the ratio changes too fast. According to working practice, analyzing shift way of continuously variable transmission system. Through the above analysis and findings, the method to control shift speed based on driving intention will be designed to make acceleration and driving comfort unified. And by limiting the maximum CVT ratio change rate, the automobile acceleration performance can be further improved.

The degree of compaction is a measure of the main evaluation index of road machinery compaction quality, but also affects the working characteristics of vibratory roller. In order to make the vibratory compaction always be in the best working state, we must adjust the operating parameters of the roller based on the real-time compaction pressure degree of the compacted material,for the best compaction effect. The paper analyzes the vibration frequency, amplitude, speed and other main working parameters and the relationship between degree of compaction,discusses how to select the main parameters, and carries out the research of Road Machinery Intelligent compaction system.

Power spectrum analysis can make EEG which the amplitude changes with time transformation for spectrum chart which the EEG power changes with time. From the spectrum chart the distribution of the α-wave, the θ-wave, the δ-wave and the β-wave, and the change of rhythm can be observed directly. On this study, the 1/f wave had been applied on the treatment of patients with mental disease , the analysis and the research of EEG before and after the 1/f wave electrical stimulation. The results show that, the 1/f wave electric stimulation has a significant effect for mental disease patients which were caused by structural damage.

To solve the writing and reading operation conflict to RAM in LED/LCD display control system, a new RAM operation conflict arbiter IC was proposed. Comparing the traditional dual ports RAM, the IC has the advantages of low-cost and high stability. By analyzing the working principle and structure design, the IC was designed in pure digital way with Verilog HDL, and passed the simulation verify. Finally the IC was realized by Alter FPGA chip and passed the actual test.

The modern city waterfront construction is an important part of the city landscape environment design, many city put it as an important part of city development strategy. The article combines the ecosystem manage engineering case of Zhengzhou Jialu river, take out the course of river manage principle and important points in the process of designing under the background of Henan Central Plains Economic Zone construction.

The electromagnetic pulse simulator designed in this paper consists of an adjustable direct current high voltage source, a capacitor for energy-storage, an air spark gap switch, a resistive divider for measurement and a GHz transversal electromagnetic wave (GTEM) cell. The analysis model is constructed based on the theory of transmission line. Influencing factors, such as self-load and impedance mismatch of the transmission line (as well as the cell), were analyzed using Pspice. The self-load has the effect of parallel connection with the load of GTEM cell. It may increase the rise-time, decrease the fall time and reduce the voltage peak. The sudden change of the transmission line impedance will make the waveform of pulse contain reflected oscillation. Four types of resistance divider link were also simulated using Pspice. Improper connection of the resistance divider will cause the waveform of pulse oscillation and lengthen the rise-time, which can be reduced by shorting the high voltage lead, using system structure with gradually changing resistance or connecting a damping resistance at the end.

These In order to overcome the behindhand and inefficient design of potato diggers, feature-based parametric modeling software Autodesk Inventor was used for the modeling of potato diggers. The swing sieve, movement simulation with ADAMS was carried out. The complex velocity acceleration and displacement curves were analyzed. Collision pressure curves were analyzed too. νis less than or equal to 500 mm/s, and αis more than or equal to 2.5m/s2, and less than or equal to 20m/s2. Test results indicated that Collision pressures of small and medium tubers are 120 Newton and 250 Newton respectively, which are all smaller than damaging pressure. Potato can be transferred freely and damage rate is less than or equal to 4% when the frequency is 5.5Hz and the swing is 30mm. It satisfies the design request.

The paper introduces the surge phenomenon of the axial-flow compressor. To ensure the blower running safely, we analyze the surge phenomenon and design a anti-surge control system by using the fuzzy control theory to control the position of the snorting valve. The result of simulation in Matlab proves that the fuzzy controller is feasible.

As time goes by, hazard rate of the society would increase if crime prediction was not implemented. Based on objective factors of offenders and victims characteristics, AHP method can be established to get a quantitative and qualitative analysis on crime prediction. Crime prediction is a strategic and tactical measure for crime prevention. According to AHP analysis, two prediction models of the optimal predictive crime locations are put forward. Standard Deviational Ellipses Model and Key Feature adjusted Spatial Choice Model were formulated to account for the anticipated position with various elements from AHP method. These models could be applied in a computer simulation of situation tests of the series murders. Besides, applying those models in certain real case demonstrates how the models work. Through models comparison, the results are summarized that Key Feature adjusted Spatial Choice Model is more conducive in confirming the guilty place. In conclusion, the suggested models, including detailed criminal map, are easy to implement.

We discuss the existence of periodic positive solution of one kind of multiple time-delay functional differential equations with the cone theory and fixed index method in semi-order Banach space of nonlinear functional analysis.