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This study aims to investigate the interaction during the co-pyrolysis of Cangzhou coal and sawdust/rice husk. The synergistic is analyzed in the thermal behavior of the blends and the kinetics by thermogravimetric analysis (TG), also in the products yield (oil and char) from the fast co-pyrolysis and the oil characterization by GC-MS and UV fluorescence spectroscopy. Firstly TG experiment indicated the synergistic effect occurs during the co-pyrolysis process of the coal and rice husk occurs during the all the main pyrolysis (300-550°C) and that of the sawdust between 300-410°C (for the 50:50 and the 75:25 blends) and 300-550°C (for the 25:75 blend). Then the co-fast pyrolysis in a novel auger reactor increased the oil yield compared to the predicted values. The synergistic interaction promoted the oxygenated compounds, limited the SOx emissions, was less reactive and did not promote the aromatic components.

The burst strength is the key parameter to the design of glass-fibre reinforced composite (GFRC) pipes with good performance and security. In this paper, the burst strength and the optimized winding angle of the GFRC pipes are derived by the theoretical analysis, experiment and simulation considering the progressive damage. The effects of the winding angle on the burst strength and failure modes are fully discussed. The results show that, the burst strengths obtained by the proposed theoretical formulas and simulation agree well with the experiment results. There is a critical winding angle for the GFRC pipes demarcating the burst modes of axial burst or circular burst. With the increase of the diameter, the critical winding angle decreases, but never less than 55° . With the increase of the winding angle, the burst strength firstly increases, and then decreases. The winding angle of the GFRC pipes should be optimized between 55° and 60° to derive the best burst strength.

A new tungstate family, Li3Ba2Gd3(WO4)8doped with Tb3+is synthesized by using a conventional high-temperature solid-state method to explore new pure green phosphors for white light-emitting diodes (WLEDs). The results from the X-Ray patterns show that the crystal structures of the hosts are composed of tungstate zigzags and the Gd3+-Gd3+units, which are isolated by the [WO4]2-groups. The critical concentration of Tb3+is up to x=2.0 in the singly doped phosphors, which is ascribed to the interaction of the isolated Gd3+ions being mitigated by [WO4]2-groups. The characteristic green emission peaks at around 547 nm are also observed, which result from the5D4→7F5transition of Tb3+ions, and the optimal doping concentration is x=2.0.

The metal would overheat and even burn under the thermal shock arisen as laser drilling, which causes micro-damage inside the metal. Cavitation is the most important origin for crack propagation and failure of metal. To understand the damage mechanism in the heat affected zone of the high temperature nickel based superalloy DD6, an experiment of microvoid nucleation was designed and implemented by laser drilling in DD6 sheet. The complex characteristics of micro-damage including microvoid near the perforation were observed by scanning electron microscopy. An analytic solution of the temperature field in DD6 sheet for thermal shock arisen as laser drilling was obtained on the basis of the non-Fourier heat conduction theory. As a result, the minimum of peak temperature during the thermal shock in the zone of microvoid nucleation was estimated, it can be approximately regarded as critical temperature of nucleation.

This paper compares three common installation ways of swing arm and carries out simulation analysis by using Adams software. The research results show that when using intercrossed enwinding wirerope, the swing arm will bear alternating load and the load variation range is huge, load G’ will change obviously and bring great impact on system control precision. When using along enwinding wirerope, the swing arm’s load is slightly bigger than wirerope tension and the load variation range is very small, load G’ will be static and it’s easy to get high control precision. By reducing the length of lower swing arm, increasing the length of upper swing arm and the offset distance, its working condition can be improved when using intercrossed enwinding wirerope.

A multi-segments stitching method is proposed to obtain two-dimensional profile of large scale aspheric components during grinding process. We firstly analyze the corresponding relation between surface features of aspherics and measurement range of profilometer. According to multi-body system theory and slope difference, a mathematical model of multi-segments stitching method is constructed. Further, the multi-segments stitching errors based on 400 mm aspheric profile are simulated with different translation amounts, rotation angles, translation errors as well as rotation errors. The simulation results indicate that the translation error is the key factor for measuring accuracy of the multi-segments stitching method. In addition, the standard deviations of multi-segments stitching errors are between 0.2 μm and 0.4 μm as the four factors are set to the proper values. To verify the simulation analysis results, an experimental setup, including Talysurf PGI 1240 and fixture, is applied to detect a 150 mm profile line on the aspheric surface. The experiment results show that the standard deviations of multi-segments stitching errors are almost within 1 μm when the rotation angle is under 7° and the translation amount is under 11 mm. The multi-segments stitching method can employ a small-range profilometer to achieve measurement of large scale aspheric surfaces with submicrometer accuracy.

Ultrafine alumina powders were synthesized through pyrocatechol and resorcinol mediated sol-gel process. Aluminum nitrate was applied as the Al source and PVP was the dispersant. X-ray diffraction (XRD) study displayed that γ-Al2O3 powders formed in the range of 800-900 °C, and then γ-Al2O3 transformed to α-Al2O3 at higher temperatures, pure α-Al2O3 powders could be obtained at 1000 °C by using resorcinol as organic monomer. The results of transmission electron microscopy (TEM) revealed that Al2O3 nanoparticles with γ crystalline phase had grain sizes in the range of 5-40 nm. Scanning electron microscopy (SEM) observation displayed that the morphology of the prepared α-Al2O3 powders had aggregated bodies formed by Al2O3 grains in the range of 0.2-0.5μm. These results provide a new way of preparation of alumina powders.

This article studies optimization design of Vibratory stress relief (VSR) technology parameter for large welded components. The test is carried through a large welded truss. It first analysis key factor of the influence on VSR technology effect. And then by modal analysis, we’ve got the natural frequency and natural modes of the specimen , The optimization design is based on residual stress distribution and natural modes of component for VSR process parameters. Test pieces are treated by vibration. before and after vibration, residual stress of the specimens is measured by the method of blind hole.The results showed that vibration mode is a key factor in determining the effect of VSR. Stress distribution is more complex for large welded components.As accordance by selecting a few of vibration modes, for VSR main technical parameters design, it can get enough vibration displacement in the areas and directions of component with residual stress. Thus we can have a good effects to relief welding residual stress.Three major parameters (Excitation frequency, excitation point, support points) are related with vibration mode. They are decided by selecting vibration mode. Excitation force is decided based excitation frequency as well as the size of the exciter eccentric , to get the right excitation force by adjusting the size of the exciter eccentric under the condition of the selected excitation frequency.

The objective of this study was to develop a novel silica modified large-sized hydroxyapatite whiskers with improved properties for use in bone repair applications. Large-sized whiskers with a mean length of 250μm were obtained by a hydrothermal co-precipitation method at 150°C, 7.5Mpa in high-pressure reactor. Silica modified hydroxyapatite whiskers were prepared by dissolving TEOS in ethanol solution, then sintering with hydroxyapatite. The compositional and morphological properties of prepared whiskers were studied by means of x-ray diffraction (XRD), Fouier transform infrared (FT-IR), scanning electron microscopy (SEM). The results indicated the evidence of nanosilicon dioxide particles on the surface of HAP whiskers. The size of nanosilicon dioxide particles depends on dropping and stirring rate. Hence, this new type of silica modified large-sized hydroxyapatite whiskers is a valuable candidate for biomedical applications.Key words: hydroxyapatite, hydrothermal co-precipitation, surface modified, whiskers

Parallel welded steel truss component is widely used in construction, tower, bridges, aerospace and other fields. And the welding residual stress is distributed complicatedly in many areas and directions, which will definitely deform the welded steel truss or even crack it. So, it is necessary to do aging treatment to avoid such thing happened, as well as improve the accuracy and reliability. Vibratory stress relief (VSR) is a new kind of technology which may eliminate the residual stress in metal component with high efficiency, energy-saving, environment protection and low cost compared with thermal stress relief (TSR). But its technical effects vary with the vibration parameters. To the parallel steel truss structures, the excitation parameter of VSR is determined by welding residual stress distribution and the natural mode of vibration. The residual stress concentration areas can get enough vibration, if the parallel steel truss component vibrates with different kinds of natural mode of vibration, which will obtain good effect of eliminating stress. Firstly, the inherent vibration mode of parallel welded steel truss component is measured by the modal analysis technology. Secondly, multiple intrinsic modes are chosen according to principle of making all the welding residual stress concentration regions and directions get enough vibration and then main technical parameters are determined such as excitation frequency, excitation point and support point. In this paper, two examples are given out: the specimen 1is treated with the transverse bending vibration mode and torsion vibration mode respectively according to the above method. As for specimen 2, it is treated with 3 exciting frequencies which are located automatically by the vibration aging machine. The residual stresses of the two specimens are measured before and after their vibrations with blind holes method. Results show that after vibration aging, the welding residual stress peak figure of the Specimen 1 is reduced by an average of 48.65% and the mean value of that dropped by an average of 32.50%. Correspondingly, the residual stress peak value of the Specimen 2 shows a decline of 3.38%, its average fell by an average of 2.55%.

Supercritical Water Oxidation (SCWO) is a unique environmentally safe technology being widely used in industrial wastewater treatment for its remarkable superiority of removes organic matters efficiently. Characteristics of supercritical water, fundamental principle and flow sheet of SCWO were introduced. Meanwhile, application situations of SCWO in different fields of industrial wastewater treatment were presented in detail, the existing problems in its application were pointed out. At last the prospect for the development of SCWO was also proposed.

An important part of the construction project evaluation is sustainability evaluation, based on the definition of sustainable development, combined with the highway construction project goal, sustainability evaluation factors on the connotation and impact analysis, the paper proposes the highway construction project goal sustainability evaluation index.

Reasons for boiler economizer tube corrosion were discussed based on results of macroscopic inspection, metallurgical microstructure examination, SEM and EDS fracture analysis. Results showed that the tube corrosion was due to sulfur corrosion that resulted in matrix exposure and led to further oxygen corrosion.

Aiming at the PLM component library system, this paper studied the characteristic and requirement of the development of the PLM component. The main goal of this research include: deploying PLM component library using open source project OpenStack and KVM; studying the component communication method under heterogeneous environments on the basis of distributing framework model Remote Method Invocation (RMI); designing PLM soft component’s facet and interface; putting forward the steps of developing the distributed PLM component based on EJB technology (include Session Bean, Entity Bean, Message Bean); issuing distributed PLM component that is packed into Web service in order to achieve the mapping between PLM soft component and Web service by using J2EE Web service component; developing a PLM component library management system based on SOA framework.

Due to the rapid growth of traffic, serious overload problems and so on, there are severe early damages on some of the highways, and affected by cold weather and water, the highways are lack of timely, quick fixes. Epoxy emulsified asphalt can be constructed in cold damp conditions, it can improve traffic conditions and extend the life of the old road and so on[1]. Given that there aren’t any relatively mature design methods at home and abroad yet, the paper is based on modified Marshall test method and studies the Epoxy emulsified asphalt mixture design method and proposes again modified Marshall test design methods.

Nonlinear processing techniques are very important tools in signal and image processing. One of the most significant classes is based on order statistics, which depends on data sorting algorithm. The sorting algorithm is very time consuming and intractable for vector data. Therefore, it is extremely urgent to put forward a fast algorithm to compute the r-th order statistics without sorting operation. The ITM and ITTM filter proposed an iteration algorithm to approach the median, from the mean. It is reasonab to generalize to the other order statistics by building a new data set Xp which is composed by the elements of the original set X. It makes the r-th order statistics of X to be the median of Xp. Then, estimating the median of the new set Xp by the ITTM algorithm, the output is estimation value of x(r).

A control platform was constructed with the features of a car carrier and two step motors, which could be controlled by changing the motors’ speed and direction based on DSP. Two motors were directly connected with the front wheels (they are both the driving wheels and steering wheels) to realize a straight line or curve driving. The hardware circuit of the experimental platform control part was designed to solve the relative connection problems, including among the development board, step motor controller, step motor; among the computer, the emulator, the development board. The control strategy of the step motor was studied based on DSP. To verify the trajectory tracking control function of the experimental platform, a circular trajectory was verified with the tracking control strategy.

In hydraulic transmission, Hydraulic pressure can not support heavy objects long time. For the shortcoming, an electro-hydraulic lifting device is designed with mechanical structural supporting; Electric motor is the motive power. The weight is lifted by hydraulic transmission technology; the base of the device is set up a lifting rigid leg and pushing forward Casters .After hydraulic system lifting heavy objects, the lifting devices rely on the support tube, mechanical positioning tube and rigid supporting legs to lock the lifting position. In order to ensure the same high of support on different positions, a vertical fine adjustment mechanism is set. The design solves the problem that hydraulic transmission cannot lift long time. The lifting device is safe operation, easy moved, accuracy positioning, and stable support, energy-saving and environmental protection.

Failure causes on a condensate pump shaft were discussed by means of macroscopic observation, chemical composition analysis, metallurgical microstructure inspection, mechanical property tests and stress analysis. The experimental results showed that the improper material with disqualified chemical composition, improper microstructure and poor mechanical properties acted as inherent factor. In addition, structure design that led to stress concentration contributed to the failure as external factor. Finally, fatigue fracture happened at the reduce section of the pump shaft.

Carbon nanotubes (CNTs) were modified by alkali, and carbon nanotubes epoxy composites samples were prepared by the hot pressing method. Dynamic characteristics of the composites were studied by experiments. The results suggest that carbon nanotubes can hardly enhance the first natural frequency of epoxy composite, but the change of second and third order natural frequencies are obvious compared with the first one. Damping properties of the composites are improved, and with the mass ratio of CNTs increasing, the first three order damping properties of composites are all increased initially followed by the decrease. The results also indicate that flexural elastic modulus of the composites is enhanced, the first and the second order dynamic elastic modulus is greater than it but the third order is opposite. The first three order dynamic modulus of elasticity moments of CNTs composites whose mass fraction is two percent are all high.

Fracture failure analysis on device clamp screws of one 110kV transmission line has been carried out based on results of macro-observation, pre-tightening test, mechanical property examination, chemical composition analysis, microstructure observation, SEM observation and EDAX analysis. It is concluded that the main reason of the screw fracture lies in misuse material and improper heat processing which led to material degradation. Suggestions are put forward finally.

In order to improve the conventional industrial brake temperature measurement and put forward new methods, measurement schemes can apply nanotechnology and nanomaterials to industrial brake temperature measurement, so that the researchers would get more accurate temperature field for analyzing the effect of temperature change on braking performance in experimental environment, and in engineering field, it can also measure and monitor braking process in real time to prevent accidents. In this paper, the author analyzes the advantages and disadvantages of the conventional industrial brake temperature measurement, and then puts forward a infrared temperature measurement scheme based on nanostructured ceramic coatings, and some suggestions on the application of nanofilm and thermoelectric conversion nanomaterials in new sensor field.

The sptitching measuring method applied in large-aperture aspheric surface optical elements can expand the range of precision measuring instrument. And the key point is developing the technique for high precision measuring data processing. To deal with the problem of cumulative errors which existed in the process of multi-section stitching, datum-transformation method was proposed, according to the characteristic of stitching measurement. The stitching measuring experiments were carried out based on Talysurf PGI 1240 profilometer of Taylor Hobson Company to verify the purpose for eliminating cumulative errors. The results show that datum-transformation method is feasible with the characteristic such as fast speed, high precision, and good operability.

The superabsorbent membranes were prepared with acrylic acid (AA) and acrylamide (AM) as the monomers, poly (vinyl alcohol) (PVA) as toughening components, potassium persulfate (KPS) as the initiator agent, and glutaraldehyde (GA) as cross-linker by means of aqueous solution polymerization. Their structures were analyzed by FTIR spectroscopy. The effects of synthesis and heat-treatment conditions on water absorbency of superabsorbent membranes were investigated. Their water absorbency with different pH was studied as well. The results showed that the superabsorbent membranes exhibited intelligently pH-responsiveness.

According to the records that the too-high temperature rise of equipment leaded to accidents easily, the temperature monitoring system based on ZigBee and GPRS, RS232 technology is designed. The perception layer uses the heterogeneous network topology by adding appropriate heterogeneous nodes to ordinary ones, which are much better than the ordinary in computing power, storage capacity, etc, and this topology structure extends transmission distance. Both of them use CC2530 chips, and the heterogeneous nodes are not only responsible for collecting temperature data, but also responsible for forwarding data from ordinary nodes. The sink nodes send alarm messages to staff by GPRS, and forward data from heterogeneous nodes to a PC via RS232. The system uses Visual Studio for software design to realize the function of data processing, display and storage, in order to achieve real-time monitoring of substation equipment and early warning.

The paper is aimed to find the relevance and feasibility between new media and urban traffic guide systems on the acquaintance of new media; to illustrate the diversified ways for information experience bought by new media; and thus to enhance the ability of information cognition and enrich the urban culture connotation.

2D-FLAC was applied to analyze the excavation process and the state of reinforcement structure, the stress statethe displacements Contour Graphthe displacement vector mapthe final settlement and the stress condition of the reinforcement structure were concluded through numerical simulation in the different conditions which the foundation pit was supported and not supported. The calculating results showed that the design of pit supporting structure was reasonable.

Five groups of vibration experiments were carried out on the 6.8 grades and M20 bolts and nuts that used on transmission tower. The test result shows that the basic way to improve the anti-loosening property was increasing the initial preload. Both increasing initial torque and appending lubrication can obviously increase the initial preload, however appending lubrication may reduce it's anti-loosening property under the situation of same preload. In the vibrating process the second stage plays a decisive role for anti-loosening property, it can be expressed as reduced rate “K” of the preload.

Partial discharge is one of the most common fault of power cable. It is of great significance to detect and analyze the condition of the power cable and locate the fault of the power cable. The model of partial discharge signal is constructed by a double exponential function. The simulation model of power cable with a middle fault is built by MATLAB SIMULINK. The transmission characteristic of partial discharge in different length of power cable and different types of power cable is simulated respectively. The simulation results show that the attenuation is proportional to the length of the same type of cable and the primary parameter of different type of power cables determines the attenuation.

Nowadays construction waste piles. For this phenomenon , this paper studied the mortar activity under different dosage of construction waste brick powder . The results show that with the increase of construction waste material content of brick powder, the mortar strength plummet .

This paper focus on and study the data acquisition problems of wireless sensor, use low power MOTE node to design the hardware platform, on this foundation discuss maximum life cycle problem of the wireless sensor network data collection process, use the mathematical description of the method for solving the data flow process, present maximum production cycle analysis method in no data polymerization conditions, further, our experimental results show that our solution. The experiment shows that this scheme is more optimized and the data life cycle of the wireless network has improved greatly.

Based on tension tests for tower bolt, it was found that the pretension increased with the extension of torque retention time, and manifested characteristics of decreasing at early stage then increasing at later stage during the tension process, that provided guidance for bolt fastening.

Aiming at the nonlinear and coupling phenomena of temperature and humidity changes appearing in the course of tea fixation, this paper introduces the fuzzy control technology in the process of making tea. STM32F107 microcontroller is as the core of the whole system and the multi-point detection system is used in real-time collection of two parameters of temperature and humidity . In addition, data transmission is realized between PC and I2C, SPI bus. The control rules and parameters of controller are formulated and the temperature and humidity of tea fixation multi-parameter control are realized. Fuzzy decoupling control is adopted to meet the process requirement of temperature and humidity change in process. It improves the precision of temperature and humidity control and the quality of tea.

A test system for subsea tree equipment is developed for tree function testing after repair. The test system mainly consists of hydraulic unit and electric unit. The hydraulic unit is developed by revamping an old hydraulic power unit, which consist of six components, including reservoir, flush/fill pump circuit, high pressure hydraulic pump circuits, accumulator group, hydraulic supply circuits and fluid return circuit. The electric unit for subsea tree is developed by using NI Compact DAQ system, In order to control the hydraulic unit and acquire the pressure signals easily. The test procedures for flowloops, valve, and hydrostatic hydraulic pressure cycling are proposed based on the factory acceptance testing of subsea tree. A test for a repaired subsea tree is performed by using the developed test system. The results show that the repaired subsea tree is good enough after repair, and verify that the developed test system works well.

Aiming at the difficulty in control in tea fixation process, the intelligent control technology is adopted in the research which is for the core to the C8051F340 SCM and adopts the multi-point detection system to collect the temperature and humidity data. Besides, the data transmission with the epistemic machine can be realized by the I2C Bus, SPI and so on while the control rules and parameters of the controller can be intended. Thus it can be seen that the multi-parameter control of the temperature and humidity can be realized in tea green removing technology. The bunk watchdog circuit is adopted in hardware design to repair the systems bug automatically and safeguard the control system operate stably for a long time in this research. Additionally, the PID control algorithm is applied in software design to control systemic error less than 2%. Practical application indicates that this system is with simple structure, high reliability and good scalability, and it also can reduce the amount of labor and improve the teas quality.

Reinforced rib is used to strengthen the rigidity of thin-walled casing structure , inhibit the vibration of the structure effectively. In this paper, Finite Element Method is used to simulate the typical reinforced rib thin-walled casing structure. Changing the reinforced rib positions and geometric parameters such as sizes, then calculate the stiffness to weight ratio and dynamic response, at the same time ,make a comparison. The result shows that: The thin-walled case with reinforced rib, the tensile stiffness and bending stiffness were increased, but the stiffness to weight ratio is presented in different geometric parameters shows differents; Under the different frequencies of excitation force load, because of the reinforced rib, the thin-walled casing structures harmonic amplitude decreases when they are under the same frequency .The result will provide reference for later thin-walled case with reinforced rib structure design.

In order to solve the problem of low accuracy of honeycomb semi-cell structures which are rolled by traditional trapezoidal tooth profile gear shaping rollers, conjugate trapezoidal tooth profile gear shaping rollers have been put forward to improve the quality of honeycomb semi-cell structures, basing on the theoretical analysis. Using ANSYS/LS-DYNA, a finite element model of rolling aluminum foils by two kinds of tooth profile shaping rollers was set up. Then results of numerical simulation indicate that the honeycomb semi-cell structures rolled by the conjugate trapezoidal gear shaping rollers are closer to the ideal size than those rolled by the traditional trapezoidal gear shaping rollers.

Landslide of expansive soil slope is a serious disease and difficult to correct in highway construction. And the mechanism of landslide of expensive soil cutting slope is complex, so the traditional slope analysis method is unable to analyze it to obtain the reasonable explanation. But the numeric analytic method can obtain the stress, strain and plastic zone of side slope analysis the distortion process of earth slope and the latent sliding plane reasonably, adopt the safety factors to evaluate the slope stability, The paper based on ANSYS and adopts the nonlinear and elastoplasticity model of soil, and use the theory of the shear strength reduction method with FEM to analysis the rule of NanYou road expansive soil landslide. Keywords:Expensive soil landslide of cutting slope swelling force FEM

By analyzing the performance of traditional audit approach in municipal engineering construction, this paper put forward the whole process tracking audit, and proposed its superiority in controlling engineering cost emphatically from the content of each auditing stage.

As one of the major projects, urban subway plays an important role in the city development. However, therere a lot of uncertain risks throughout the entire construction process, any improper handling may lead to serious safety accidents and incalculable property damage, so it is essential to take full concentration in the urban subway risk management. This paper divided risks that may encountered in the process of subway construction into three parts, and gave advices from four aspects so as to effectively prevent and mitigate the subway risk, thus ensure the achievement of the subway construction.

In the design and practice of landscape, the higher cost in landscape design often causes much more landscape resource waste, ignores the economic benefits of landscape and destroys its aesthetic sense. Through analyzing the relation between landscape and economy and introducing a set of concepts, planning, purchasing, manufacturing, marketing and service. In this article, we apply the theory of "supply chain management, SCM " in economics into the landscape design and its practice. To make the management more scientific, accurate, reasonable and efficient, we must keep two principles , reducing and controlling the cost and increasing its efficiency of landscape design and its practice. Also we may realize the organic coordination of the whole economic activities by this way.

Failure reason of boiler extraction steam pipe was discussed by means of macro-observation, chemical composition analysis, metallurgical and SEM microstructure examination and EDS analysis. Results showed that the crack initiated from original corrosion flaw on outer wall of the extraction pipe, propagated rapidly under large pressure caused by water-hammer due to no drainage design in the unit pipe system until final bursting.

Through the concept of benefit-cost and the comparison with financial evaluation, this article expounds the method and applicability of benefit-cost analysis, and gives three indicators which are economic internal rate of return (EIRR), economic net present value (ENPV) and benefit-cost ratio (RBC) to analyze the feasibility of construction project.

In order to improve the efficiency of offshore oil drilling, simplify the structure of drilling rigs, a new type of heave compensaton drawworks is put forward to realize decoupling control of motion and energy saving by hydraulic energy storage. In order to study the compensation performance of drawworks, mathematical simulation model is built, heave compensation displacement controller of fuzzy-PI and bit pressure controller of BP neural network are designed based on the high inertia load and nonlinear time-varying characteristics of the system. The simulation results show that the heave compensation maintains the absolute displacement of the hook within certain premises and reduces the effects on bit pressure by platform heave movement, automatic bit feeding keeps bit pressure steady, the bit pressure is kept in the scope prescribed by work. The research result shows that the device well meets the performance requirements of offshore drilling.

Leakage causes of boiler low temperature reheater were discussed by means of macroscopic inspection, chemical composition analysis, metallurgical microstructure examination, SEM and EDS fracture analysis. Results showed that the reheater leakage occurred for cracks originating from the fillet seam of ear plate. The main causes lie in improper structural design of the ear plate welding directly on the reheater elbow where suffered from complicated stress condition, wall thinning and out-of-round. In addition, as a weak zone, heat effect zone of the fillet welding seam was more likely to crack under fatigue stress for frequent unit start and stop and pipeline vibration. Installation stress existed between the ear plate and support block also contributed to the cracking. Suggestions were provided to avoid similar accident based on the comprehensive analysis of leakage causes.

In order to test the security of cryptographic devices against Side Channel Attacks (SCA), an automatic general-purpose power analysis system (TH-PAS-01) is designed and implemented. TH-PAS-01 is scalable and can be applied to many cryptographic devices when specific modules are installed. Using the system TH-PAS-01, correlation power analysis (CPA) are carried out on an AES chip under two working models: normal and shuffling mode. The security level of the countermeasure provided by the target chip is verified by TH-PAS-01. The experimental results show that the correct key of the AES chip is obtained with around 50,000 power traces when the chip was working under normal mode, while the whole key bits are not obtained with 960,000 power traces when the chip works under shuffling mode. The automatic general-purpose system TH-PAS-01 is feasible for security analysis on power analysis for cryptographic devices.