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Shift reactors are widely used in the petroleum and chemical industries, and especially in the coal chemical plants. The degradation of the reactor is critical to the safe operation of coal chemical plant. In this paper, a shift reactor after 8 year service was chosen. The test block taken from the reactor cylinder with the stainless steel clad plate was used and the test samples from the test block were prepared. And then, chemical composition analysis, metallographic examination, tensile and hardness tests were performed. The scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD) method were used to study the degradation and degradation mechanism of the reactor. The metallographic analysis results show that there were a large number of carbides segregated in the grain boundary and the intergranular cracks were observed for the samples in the weld zone of the stainless steel clad plate. The SEM and EDS results indicate that the corrosion medium (i.e. polythionic acid) was found in the fracture surface of the samples from the weld zone of the stainless steel clad plate. The XRD test results show that the tensile residual stress occurred for the welding of the stainless steel clad plates. It is found that the degradation mechanism of the shift reactor was due to the polythionic acid stress corrosion cracking.

A proton exchange membrane (PEM) fuel cell is an electrochemical device that directly converts chemical energy of hydrogen into electric energy.The structure of the flow channel is critical to the PEM fuel cell performance. In this paper, the effect of the cathode flow channel baffles on PEM fuel cell performance was investigated numerically. A three-dimensional model was established for the PEM fuel cell which consisted of bipolar plates with three serpentine flow channels, gas diffusion layers, catalyst layers and PEM. Baffles were added in the cathode flow channels to study the effect of the cathode flow channel baffle on the PEM fuel cell performance. And then, numerical simulation for the PEM fuel cell with various cathode channel baffle heights ranging from 0.2 mm to 0.6 mm was conducted.The simulated results show that there existed an optimal cathode flow channel baffle height in terms of the electrochemical performance as all other parameters of the PEM fuel cell were kept constant. It is found that the PEM fuel cell had the good electrochemical performance as the flow channel baffle heights was 0.4mm in this work.

Both assembly force and temperature play an important role in the proton exchange membrane (PEM) fuel cell performance. In this paper, contact pressure between bipolar plate and gas diffusion layer (GDL) in a PEM fuel cell under various assembly forces and at different temperatures was studied numerically. Considering the coupling effects of assembly force and operating temperature on contact pressure, a three-dimensional finite element model of the PEM fuel cell was established and the contact pressure between the GDL and the bipolar plate was studied using commercial code ABAQUS. In order to verify the simulated results, the experimental study was conducted to investigate the contact pressure distribution between the bipolar plate and the GDL. The experimental results are in good agreement with the finite element method (FEM) results. The simulated and experimental results reveal that the contact pressure increased with the increase of assembly force and temperature. It is found that the contact pressure distribution between the bipolar plate and the GDL had the best uniformity under the applied torque of 3.0N·m and at the operating temperature of 80 °C in this work.

In order to investigate the mature law of Korla fragrant pear with mathematics method, Korla pears in Aksu area be taken as the study object, and the fruit hardness and soluble solid content (SSC) be selected as the research index. The data of the two indices in the mature process are analyzed with Excel, SigmaPlot and Matlab. To draw the change rule of indices and establish the mathematical mode. The research shows that the effective accumulated temperature reaching up 3000°C to 3843°C is main mature stage of the Korla fragrant pear, and there is an accelerating stage in which. The change rule can be precise description by the established mathematical model that can provide reference for fruit maturity modeling.

Deployment of passive monitoring for IP flows in IP network is a prevailing research in last decade, the primary goal of monitor deployment strategy is to maximize the fraction of monitored flows while minimize the cost induced by the monitoring work. Previous researches often get global traffic information which cannot be easily fetched, and use the heuristic algorithm to get a solution. In this paper, we only use link load and route information to deploy the flow monitors, and a two stage algorithm is used for the deployment strategy. Our simulations and experiments demonstrate the effectiveness of our algorithm, which show that, by using the flow information estimated from the link load and route matrix, it is sufficient to give an effective flow monitor deployment strategy to maintain a high level of measurement coverage and make the cost reasonable in practical condition.

For the bush-burning problem in the course of the engine operation. Taking a certain kind of engine as reference, build a 3D geometric model of the engine-oil flow field in the ideal stable conditions with GAMBIT and conduct a simulation of it with FLUENT. It reveals that we can have an intuitive understanding of the flow state and pressure distribution of the engine-oil inside the clearance between the crankshaft main journal and crankshaft bearing as well as the rod journal and rod bearing which provides basis for a further refining of bearing lubrication system, improving the lubrication method and enhancing the efficiency of the lubrication.

The statistical histogram algorithm is one of the common background update algorithms. Considering the statistical histogram algorithm disadvantages of large complex computation, the paper proposes an improved method named fixed window statistical background updating algorithm. The algorithm sets a window which contains N records for each pixel point firstly, every record records value in the permissible range of error and the number of pixel point occurrence, and then counting pixel values for every record through statistical histogram algorithm. When the window is full, the new pixel values will replace the smaller counting, while the pixel which counting larger will be adaptively updated by adaptive background updating formula. The experimental result shows that this method has a high real-time performance and robustness in background updating.

The degradation of chlorpyrifos is investigated with the treatments of sonolysis, ozonolysis, and sonolytic ozonolysis at various frequencies. Results show that there exists frequency effect in sonolytic ozonolysis. In sonolytic ozonolysis, the maximum degradation rate is obtained at 495 kHz, and the degradation kinetics is fitted to the first-order kinetics model well. However, the most significant synergistic effect between ultrasonic and ozone is at 124 kHz. The kinetics parameters indicate that chlorpyrifos is much more labile to ultrasonic at 495 kHz, while ozone is much more soluble at 124 kHz. The hydrolysis and oxidation are deduced to contribute to the degradation reaction and the degradation pathway for chlorpyrifos degradation is proposed.

ECM aiming at fire control radar is an effective method for improving ship-to-ship missile penetration capability. Based on the analysis of Doppler fire control radar working principle, Doppler fire control radar countermeasures strategy is brought up. The repeater jamming technology applied to the ship-to-ship missile, aiming at Doppler fire control radar, and its application conditions are lucubrated. The research has positive significance to the weapon equipment development and operational application.

This paper concerns trajectory tracking control of AGV. The model of forked AGV was simplified from a three-wheeled vehicle model to a “bicycle” model. The dynamic model of vehicle lateral motion was built depending on Newtown’s second law and the analysis of lateral tire forces. The optimal control linear quadratic regulator was applied to achieve trajectory tracking control. Use the MATLAB and CarSim to simulate. The satisfied results proved that the control algorithm was effective and could make the system stable.

This paper reports a design proposal of a sonochemical setup for pesticide wastewater degradation. Multi-parameters obtained by multi-sensors of the setup were utilized to control experimental variables and analyze degradation effect. Based on the setup and method designed, degradation experiments of deltamethrin were set up. In the work, treatments using ultrasonic, ozone, and the combination of them were carried out respectively, and parameters including ultrasonic frequency, pH, electrical conductivity, temperature as well as mass were taken into consideration. Results indicated that deltamethrin could be degraded efficiently under the irradiation of 589 kHz US/O3 combined and the degradation rate could reach 91%.

Retracted paper: In recent years, much research has been devoted to the emulation of the Turing machine; unfortunately, few have simulated the emulation of the partition table. In fact, few cyberneticists would disagree with the construction of symmetric encryption, which embodies the structured principles of algorithms. We propose a novel heuristic for the synthesis of linked lists, which we call Carl.

The atmospheric corrosion behaviors of AZ80 magnesium alloy are investigated by exposure test in different testing sites. After four months exposure test, the corrosion morphologies and the component of the corrosion products were observed by the scanning electron microscopy (SEM) equipped with energy-dispersive analysis of X-ray (EDAX). The corrosion rates of AZ80 magnesium alloys were calculated by mass-loss. The results indicated that the corrosion resistance of AZ80 magnesium alloy in the sea environment is the worst. The corrosion degree of the back surface is worse than the front side. The corrosion products are mainly formed by carbonate, and contain small amount of chloride in most environments, while in Xishuangbanna and Jiangjin area contain a little sulfate.

To evaluate the safety of a steel box bridge during the construction of a metro station, the process of excavation which was based on the metro station and its overpass bridge in Chengdu was analyzed. A detailed FE model was established which include the soil, the station and the bridge using general finite element software ALGOR. According to the procedure of the constructing station and completed station, investigating the absolute settlements and differential settlements of the earths surface and foundation in metro station incidence, the effect on the steel box girder overall stress and local stress was analyzed extensively. The results demonstrated that the excavation has a insignificant influence on the deformations and stresses of the steel girder. Thus it provides an important understanding of the interactions of bridge structures and underground constructions.

Stability, fast-settling and anti-noise abilities are the three necessary parameters to measure the performance of Phase locked lock (PLL). By using of a LPF with strong noise-suppression ability and replacing multiplier of PD with an adder, an improved PLL is proposed in this paper. Compared with the Costas Loop and Saber's PLL, the proposed PLL has better phase tracking ability, shorter settling time, and stronger anti-noise ability. It is expected that our work will be helpful for developing PLL with lower-price and higher-performance, and then contribute to more applications in communication.

Intelligent Mouse is a micro-robot with special wisdom and it is a typical electro-mechanical integration system. This document has detailedly described the facture of mechanical structure, circuit design, software algorithm and other hardware system configurations. For the hardware, the control center of this mouse has used LM3S615 microcontroller which is based on the ARM® CortexTM-M3 v7M architecture developed by Luminary. This document also introduced that, the left/right-hand searching of the mouse, mapping, and calculation of the shortest path.

In the analysis of car frame that considers the leaf spring, the three degrees of freedom model of leaf spring was proposed. It would be compared with the commonly used equivalent model at present. There is a clear difference between the impacts of the two models on the structure analysis of the frame. The stress and deformation of the frame with the three degrees of freedom model is greater than the commonly used equivalent model, and there is only a smaller value range of lightweight optimization. Through the comparison between the two models, it can be seen that the three degrees of freedom model can transfer force and moment of force in all degrees of freedom, which illustrates the stronger reliability of the three degrees of freedom model of the leaf spring.

This paper studies the realization method of QPSK modulation and demodulation circuit based on FPGA.And the simulation results are given under the environment of MAX+PLUSII .In this paper, the scheme uses phase selection method, compared with the modulation and demodulation method commonly used, design more simple, more suitable for FPGA implementation, the reliability of the system is higher.Through the analysis of the simulation waveform shows, the very good realization of the QPSK modulation and demodulation function.

Quadrature Phase Shift Keying as a efficient modulation mode to be used in wireless communication. it is significant to study its implement. This paper presents a method to design QPSK modulator and demodulator, which use field programmable gate array. We will analysis the principle of QPSK modem and will give the design method, display the block diagram of the system in this paper and discuss its feasibility. The whole system is divided into several small models. Because space is limited, we can only introduce some key modules. Such as carrier recover and bit synchronization

A typical cold bending process of curved plate girder in building construction was investigated in order to reveal the principle of deformation shape of curved I-shaped plate girder. An improved calculation method basing on geometry analysis was proposed to predict the geometric relationship between the residual deformation of curved I-shaped plate girder and the offsets of all segments in successive loading process. An example referring to the existing literatures was adopted to revise the efficiency of such an improved method. The results illustrate that the final offset distances of the key points, which were used to divide the girder into several segments with the same length, can be simply obtained by summing up the offset of each segment in once typical loading process, and the final residual deformation of curved girder was depended on the forming angle of each segment of I-shaped plate girder in once typical loading process.

Algorithmic relationships are discovered here for programming tutoring. There are two kinds of algorithmic relationships between programming resources on the web: associative relationship and structural similarity relationship. They can be organized as a hierarchical body. An algorithm can solve different programming problems and a programming problem also can be solved by different algorithms. Thus, there is such algorithmic relationship, or associative relationship, between these programming resources on the web. The algorithmic structures of source codes can be mined by neural computing. Different source codes may have a structural similarity relationship between them, meaning that they are similar in their algorithmic structures. A learner can learn algorithms from simple to complicated structures or from similarities in their structures. In our experiment, we use a tree structure to organize the algorithmic relationships.

ATmega128 single-chip microcomputer was regarded as control core, the diesel engine speed and pressure signal simulation hardware circuit were designed based on digital to analog converter TLC5618, clock chip DS12C887 and analog signal processing unit SY4-20mA-P. According to the equipment evaluation process, the sequential turbocharging control instrument automatic assessment program was compiled in the reference of real-time. The sequential turbocharging control instrument factory automatic evaluation function was realized which improve the production efficiency.

Taking a six-storey steel frame construction as the research object, parameters under study are the horizontal space of braces’ nodes and the layout of vertical braces. Based on the analysis of the structural period, layer displacement and angles of storey drift, research on the influence of layout of braces on structural dynamic properties of large space buildings is conducted. The results show that when column spacing is larger, braces-setting contributes to significantly improve the structure’s lateral stiffness and reduce the section size of columns, and that the section size of braces can be reduced by shortening the horizontal space of braces’ nodes. Braces should be set between the columns as full as possible. It is better to set the vertical braces positioned in the center instead of on the side between the columns. The lateral stiffness is higher when braces are set concentratedly than dispersedly. It’s more economical to set the inclined braces uniformly.

A number of image filtering algorithms based on nonlocal means have been proposed in recent years which take advantage of the high degree of redundancy of any natural image. The block-matching with 3D transform domain collaborative filtering (BM3D) proposed in [1] achieves excellent performance in image denoising. But the choice of shrinkage operator in block-matching step is not discussed, only given the threshold by experience in its related papers. In this work, we introduce an improved version of BM3D with adaptive block-match thresholds. The proposed method firstly seeks the relationship between the Structural Similarity index (SSIM) [2] and match distance in blocks and obtains the data with fine SSIM values. Then, compute the Noise level and Gradient values in blocks of the same block size. Finally, surface fitting is adopted to get a formula which applies weak thresholds for flat blocks and strong thresholds for detail blocks. Experiment results are given to demonstrate the same class of denoising performance with less time-consuming to slightly noisy image and good improvement in denoising performance to seriously noisy image.

The development trend of TRIZ is to be a method that can create and solve problems universally and ultra professionally, so it can be applied to all areas including management innovation. According to the general flow of problem solving of TRIZ, this paper analyses the restrictions of TRIZ used in the management innovation systematically, and it points out that constructing the conflict theory based on management parameters and contradiction matrix is the bottleneck problem.

In order to raise the rifle grenade accuracy of firing and strengthen infantry to the future applicability of modern warfare, this paper has been in progress to application on the rifle grenade of one-dimensional the trajectory correction technology. The position in the modern war of rifle grenade with the effect was pointed out in this paper. From now available one ties up the trajectory correction technology to set out, and several kinds of ballistic trajectory identification knowing the feasibility that the method was applied on the rifle grenade comparative analysis, and the trajectory identification based on sequence of velocity-time was done simply the introduction. Possess the guidance meaning to follow-up one dimension the application study on the rifle grenade of trajectory correction technology.

With the research model of intelligent flexible structure by Fiber Bragg Grating (FBG) sensor, the dissertation deals with a design and manufacture methodology for FBG sensor array based on orthogonal curvatures, and offers the experiential analysis and validation. On basis of brief introduction to the principle of FBG sensor to detect curvatures and methodology of structural morphological reconstruction, detailed description of design solutions and manufacture processes have yielded based on orthogonal distributed FBG sensor array which includes some technological parts as the configuration of orthogonal distributed FBG sensor array, the technology of perception range-proportion and orthogonally contrapuntal-pasting, the method of casing and encapsulation, calibration for model structure and so on. Fitting and reconstructing of the model structure and validation of visualization is split up based on intelligent flexible model structure we make and experimental platform we develop. Thus, the result of the experiment adequately shows the FBG intelligent flexible structure designed and produced in the dissertation gives a splendid on fitting and reconstruction, in which the feasibility and validity of the design methodology and key technology has been proved deeply.

Though with its big restoring force and large deformation characteristic, shape memory alloy (SMA) is commonly used in the research of active vibration control for smart structure, the presence of its thermal hysteresis often leads to bad control performance. A vibration control method based on alternate multichannel driving SMA is proposed to improve the SMA based smart structural vibration control performance by reducing the effect of thermal hysteresis of SMA. The technical methods, the design of the experimental structure, the construction of the experimental platform is illustrated, with the principle and operating process of the experiment and experimental results described. By embedding the SMA driving elements into the epoxy substrate and mounted epoxy plate into the framework of the aircraft prototype, experimental analysis and verification is done. The experimental results show that alternate multichannel driving of SMA for vibration suppression of smart structure is feasible, and the performance is improved to a certain extent.

Hanging file stent components (HFSC) of automotive transmission require high reliability, because the assembly quality has direct influence on the whole vehicle performance, especially in the area of security. But it is easy to make mistake in assembling it, and it is hard to detect errors, because the HFSC has many different parts, which have similar shape. This paper analyzes the geometrical features of the hardware of HFSC, and helps to find out those parts needing inspection through researching the possible mistakes. According to the results of the analysis, an automatic inspection system which is controlled by microcontrollers for HFSC quality measurement is designed. This system uses a new sensor designing according to the necessary of detection, and a suitable sensor planning program is presented. After the accomplishment of this system, it is proved flexible and effective through half year of practice.