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Epoxy is a polymeric material that is widely used in various fields as an adhesive, coating, and bulk material due to its outstanding properties. Many research studies on reinforced polymers have been conducted by adding micro/nanoparticles or fibers to attain better tribological properties. However, the tribological properties of patterning on the epoxy surface are relatively obscure. In this study, friction and wear properties of flat and V-groove patterned epoxy specimens were analyzed in dry and water lubricated sliding conditions to assess the effectiveness of the surface pattern in reducing friction and wear. It was found that under low applied force conditions in which the V grooves remained almost intact, the surface pattern contributed to decreasing the friction coefficient as much as 0.12 and increasing the stability of frictional behavior in dry sliding condition. This outcome was attributed to the ability of the grooves to trap wear debris inside the cavities. However, under water lubrication with polytetrafluoroethylene (PTFE) particles used as additives, the V-groove specimens were less effective in reducing friction due to the relatively small contact area. As the contact area increased, the effect of water lubrication with PTFE particles in reducing friction could be enhanced. These results are expected to serve as a fundamental basis for designing and fabricating the surface of polymeric components for tribological applications in dry and lubricated conditions.

We introduce multi-games with aspiration-driven updating rule and investigate the evolution of cooperation. In our work, a percentage of players randomly choose to play the PDG, while the remaining players play SG. Meanwhile, a part of players randomly select to use the aspiration-driven updating rule, and the other part of players select to use the Fermi-function updating rule. We find that both the diversity of sucker's payoff and updating rule have a positive effect on the cooperation. Besides, when the contribution of the sucker's payoff is larger or more players use the aspiration-driven rule to update the strategy, more cooperators appear derived from the spatial distribution of strategies and special network reciprocity. What is more, when more players choose to play SG and simultaneously use the aspiration-driven rule, cooperators gradually flourish. In addition, we also reveal that the easily contented players prefer to cooperate.

The traditional MVC pattern has several shortcomings in Android application development, such as complex structure and too tight connection between Controller and View.The key class Activity in Android is the combination of Controller and View classes, which is not only responsible for the operational logic, but also responsible for the display. The Activity has a high degree of coupling. The Presenter introduced by MVP model completely separates the Model layer from the View layer,which solves the problem of overly bloated activities and also helps in later testing and maintenance. This article analyzes the shortcomings of traditional MVC application development in Android, and explores the feasibility and advantages of MVP mode in Android development, and finally implements the application of MVP mode in Android-based data monitoring system.

The study on microbial community composition in rhizosphere soils surrounding different order roots is of great significance for understanding the interactions between roots and microbes. Using Illumina Miseq sequencing technology, this study analyzed the differences of fungal community structure in bulk soils and rhizosphere soils surrounding different root orders of poplar (Populus × euramericana 'Neva') tree. The microbial species annotation showed that 128, 124, 130 and 101 fungal genera were classified in the rhizosphere soils around 1-2 order roots (R1), 3 order roots (R2), 4-5 order roots (R3) and in the bulk soils (NR), respectively. The differences of present fungal genera indicated a selectivity mechanism driving fungal community assembly in poplar rhizosphere soils. There were seven fungal genera with more than 1% of relative abundance in rhizosphere soils. Trichoderma was the dominant fungal genus in R1. Trichosporon and Aspergillus were the dominant fungal genera in R2 and R3, respectively. Alpha (α) diversity indices showed that the fungal diversity was significantly different among root orders. Specifically, the diversity of soil fungal community in the rhizosphere soils around lower order roots was significantly higher than that of higher order roots (P＜0.05). Beta (β) diversity indices showed that the dissimilarity of fungal community composition increased along with the root orders. All these results implied the different composition and structure of fungal community are closely related with the function of fine root orders.研究不同根序细根根际土壤微生物群落组成结构对深入了解根系-微生物互作关系具有重要意义.本研究采用Illumina MiSeq测序平台,对杨树人工林非根际土壤和不同根序细根根际土壤的真菌群落结构进行分析.物种注释结果显示: 杨树1～2级根(R1)、3级根(R2)和4～5级(R3)根际及非根际土壤(NR)中分别包含128、124、130和101个真菌属,表明杨树根际存在对真菌群落构建的选择性机制.不同根序根际土壤中相对丰度1%的真菌属有7个,木霉属在1～2级根根际土壤中丰度较高,毛孢子菌属和曲霉属分别是3级根和4～5级根根际土壤中丰度最高的真菌属.

With continuous improvement and update of embedded Linux kernel, embedded technology has been widely used in handheld devices and industrial control field. Therefore, a user-friendly graphical user interface (GUI) is essential for these applications. This paper firstly presents the design method for transplanting Qt on embedded platform of ARM9. Secondly it elaborates the device driver development and Qt interface development in Linux system with a Qt test program. All transplantation method of Qt and test program have been tested and verified on the ARM9 platform.

In this paper, 0.05 grade three-phase main control system of multi-station meter testing equipment (MTE) is presented. This design is based on the S3C2440 core board as the control core, and the software is based on Windows CE(WINCE) embedded operating system. The device is displayed and controlled by 7-inch Touch Screen. The main control system communicate with the error instrument and PC through Controller Area Network (CAN) bus, and the largest number of error instruments can connect to CAN bus is 100. The main control system communicates through RS232 bus with three-phase signal source and standard electric energy meter, through RS485 bus with programmable power amplifier. In this device, calibration of energy meters can not only through the PC software, but also use the main control system. Compared to the traditional design of the electric energy meter calibration device, the design’s the man-machine interface is more optimized, the number of electric energy meters can be test in the same time is more, faster communication, stronger anti-interference ability, and calibration is more efficiency.

This paper is about how to design an improved anti-ribboning method for the winder system. The system is based on the principle of a brushless DC motor control, which constantly changes relative velocity between the grooved drum and the yarn bobbin. This in turn, causes the changing of the winding ratio value. Therefore, it will accomplish the anti-ribboning control. Compared with the traditional anti-ribboning methods, the improved method can save more mechanical components and maintenance costs. Also, this method can develop different programs for different yarns. Therefore, this method is more efficient and versatile.

This paper analyzes the negative influence of dead-time,point out the shortcomings of traditional dead-time compensation methods , and then present a dead-time compensation method. Simulink simulation shows that the proposed method is effective. The proposed method is applied to a 15kW inverter which is controlled by STM32F103 MCU,and it can significantly reduce the THD value of the inverter output voltage waveform. The experiment proved that this method is simple and reliable, with good results.

In order to improve the step accuracy of two-phase hybrid stepping motors, this paper presents a high-performance stepping motor driver based on controllable dead-time compensation. After CPLD(Complex Programmable Logic Device) logical processing, the subdivision drive signal created by microcontroller STM32 becomes a complementary dead-time compensation drive signal which can realize precise control of stepper motor. The experiment shows that this program not only has effectively reduced the power consumption of the stepping motor, but also made whole system cost less.

Biological island grid system (BIGS) is a new type of biological floating island which allows for larger bacterial population to grow in the system. In this study, the nutrient-removal efficiencies of two different BIGS, constructed with Oenanthe javanica and Iris pseudacorus were investigated. Molecular technique was used to study the microbial mechanisms of pollutants removal. Results showed that BIGS had an excellent long-term removal performance compared with conventional biological floating island. The -N-removal efficiencies of BIGS were 89.5 and 91.2%, which were 16.3 and 16.9% higher than the control, respectively. Over 75% of chemical oxygen demand (COD) was removed in both BIGS while the COD-removal efficiencies were only 71.4 and 69.1% in the control. Analysis of DGGE pattern showed that the diversity index of the elastic space in BIGS was 1.93–2.65. Furthermore, month played a main role in microbial community structures. About 46.2% of the micro-organisms in the system belonged to Prot...

In this paper, a gas stove and range hood integrated intelligent control system based on wireless communication is introduced. This system enables range hood running through wireless communication without human intervention, and gas stove can directly and automatically control the opening, the wind speed and closed of range hood. Compared to traditional gas stove and range hood, it implements the gas stove and range hood work together to make the operation more safe, convenient and fast. Through experimental test, the proposed design is feasible to achieve the gas stove and range hood integrated intelligent control system design requirements.

In this paper, a kind of variable frequency and multi-pressure water supply control system based on STM32 processor is designed. It can adjust the water pressure dynamically, according to the changes of water flow. Therefore, it can economize the energy consumption significantly. In order to improve real-time performance, the system adopts STs STM32F407 series processor which is based on ARM® CortexTM-M4 32-bit RISC core. It is used to collect the water flow, pressure and other data in real time, and automatically adjust the output frequency to control the motor speed, according to the set pressure value, and ultimately control the flow and pressure of the water supply system. According to the test, this variable frequency and multi-pressure water supply control system based on STM32 processor can meet the design requirements.

We have designed a photoelectric yarn signal acquisition system, which is based on the STM32 processor, having a sample rate up to 270kHz, and uploading data collection through synchronous parallel communication mode; Owing to the large noise of yarn signal and the unobviousness of yarn defect, we respectively adopting wiener filter and mean filter to filter this signal; The simulation result of matlab has manifested that both the wiener filter and mean filter can effectively decrease the noise level of the yarn signal and make the nep defects easier to identify, and that the wiener filter applies to application where the yarn speed is higher , while the mean filter is appropriate to the lower speed spinner.

In this paper, the application of a FPGA-based large-screen and high-resolution display accelerator technology in full-automatic textile machinery (computerized flat knitting machine) is studied. The design of traditional computerized knitting machine system is difficult to support the display of large screen and high resolution operating interface. Therefore, a displaying accelerator is designed in this paper. It comprises of FPGA, configuration chip, SDRAM and LVDS transmitter chip, is located between the embedded main processor and high resolution TFT LCD screen of computerized flat knitting machine, and implements the modules such as display acceleration logic and SDRAM controller relying on Verilog HDL programming in FPGA. The computerized flat knitting machine, applying displaying acceleration technology, can present its dynamic color interface on an 800 x 600 resolution TFT LCD (10.4") on the condition that real time, reliability and cost can be ensured.

In this paper, the merit and disadvantage of existing measurement methods for battery internal resistance are firstly analyzed. Then an online internal resistance measurement based on AC impedance method is proposed, which can increase the stability of the excitation source and enhance the performance of the filtered feedback signal. The method can be used to measure the small resistance of lithium-ion battery precisely. Experimental results show that the proposed method is accurate.

CPUs in embedded systems sometimes have limited performance for the sake of cost, so there may be impossible for these systems to drive a LCD display with a high frame rate. An FPGA based schema is proposed to increase the frame rate of the LCD display so that the texts etc. can be seen fluently. The frame rate enhancer is composed of three parts, an FPGA for receiving the data to be displayed, an SDRAM for data storage and an LCD controller for display control. The designed frame rate enhancer can be used in an embedded system, which has a large LCD display but a low performance CPU, without any flicker.

The batteries in a battery pack may have different internal resistances, and this inconsistency may lead to fast aging of the whole pack. In order to overcome the shortcomings of existing equalizing charge method, a bidirectional energy transfer mechanism based battery equalizing charge schema is given. We detailed analysis the working principle of equalization circuit and equalization work process, and the program analysis and argument by experiments. Experiments show that the method structure is simple, and it can quickly realize the dynamic transfer of energy between the batteries. The battery power charging imbalance can be effectively solved.

In this paper, the application of a FPGA-based large-screen and high-resolution display accelerator technology in full-automatic textile machinery (computerized flat knitting machine) is studied. The design of traditional computerized knitting machine system is difficult to support the display of large screen and high resolution operating interface. Therefore, a displaying accelerator is designed in this paper. It comprises of FPGA, configuration chip, SDRAM and LVDS transmitter chip, is located between the embedded main processor and high resolution TFT LCD screen of computerized flat knitting machine, and implements the modules such as display acceleration logic and SDRAM controller relying on Verilog HDL programming in FPGA. The computerized flat knitting machine, applying displaying acceleration technology, can present its dynamic color interface on an 800 x 600 resolution TFT LCD (10.4") on the condition that real time, reliability and cost can be ensured.

The technology of Needle selection is one of the key technology for computerized flat knitting machines. Proceed from the structure of the needle selection system, the working area for needle selector, pattern data, selecting needle slice instruction, this article researched the needle selection control system in detail. On condition that computerized flat knitting machines' working accuracy, stability, real-time, high efficiency is guaranteed, it put forward the test plan to the control logic of needle selection. This article provided a theoretical reference and practical significance for the computerized flat knitting machine's research and development.

Given the traditional use of sensors of temperature, humidity, smoke to identify the fire hazard, this design adds the image recognition algorithm based on OpenCV to identify fire through capturing images with camera, and caculates the probability of fire hazard according to weight of four factors that influence fire occurrence. The weight is determined by integrated multifactor probability model. Integrated fieldbus Redundancy technology is used in transmission of data on Ethernet and CAN. The practice has showed that the system achieved stability, high reliability, fast, and accuracy. The alarm is given rapidly when fire hazard happens.

The paper presents a fire detection method using HSI model and an improved Codebook model. Based on the statistical feature of fire, we can extract fire-like pixels with HSI model. Owing to the fact that fire is extending and flickering, we propose an improved Codebook model for background subtraction. As a result, moving objects (for example, fire, moving cars) can be detected. At last, utilizing a pixel fusion method, we add the dynamic and statistical fire-like pixels with different weighted values. Experimental results show that our fire detection algorithm is effective and robust . Keywords : Codebook; HSI; Pixel Fusion; Fire detect; Computer vision 1. INTRODUCTION Fire detection is an important issue in our daily life. Decades before, people have begun to do research work on fire detection. Early fire detection are mainly based on smoke sampling, temperature sampling and relative humidity sampling, in addition to the traditional ultraviolet and infrared fire detectors. However those methods are sensitive to environment changes and may not always reliable. To provide more reliable and robust detecting method, the method based on video sequences is becoming more and more interesting. Visual based detecting fire systems generally make use of three characteristic features of fire: color, motion and geometry. In [1], T. H. Chen et al. introduce a new fire extraction method by color model and an image difference technique, but the detected fire has some holes. In [2], D. Han and B. Lee store a normal state image and use input images to subtract the normal state image. Then they utilize slope density function to distinguish fire from other lights. Backgrounds are changing, so their method may give wrong alarm if they don’t update the normal state image. In [3], B. H. Cho et al. presents a method which is similar to the method in [1]. Their method uses average values as threshold values, but when moving regions are larger than fire regions, their result may have more non-fire pixels. In this paper, we try to extract the integral fire from the frame and reduce the disturbance, especially the fire-like background disturbance. We use our improved Codebook model to detect foreground objects. Finally we use pixel fusion method to extract real fire from the two frames processed by the HSI and Codebook models.

This paper started from the architecture of computerized flat knitting machines, Briefly introduced the hardware platform of computerized flat knitting machines, then highlighted its software design, and separately analyzed the CAN and GPIO bus drivers in details. By interpreting CNT and PAT files, it creatively proposed the sequence of weaving for the control system. By using SDL, it realized the GUI program.