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In order to increase the measuring range of the moment of inertia, a new measurement equipment with triple torsion bars based on torsion pendulum was designed. The equipment could switch the number of torsion bars from single to double or triple by inserting or extracting two movable pins and implement the function of three different measurement devices. The detailed deducing process for the measuring range of the moment of inertia at various measurement states was given. The results show that the measuring range of the measurement equipment has been significantly improved compared with other equipment using single torsion bar or double torsion bars and verify the effectiveness and practicability of the measurement equipment.

Taking bridge structures in service period as research objects, durability experimental method of reinforced concrete (RC) components strengthened with fibre reinforced polymer (FRP) under time-varying hot-wet environment and random fatigue load coupling/interaction was discussed and corresponding experimental system of structural components was developed and integrated. To prove the effectiveness and feasibility of the experimental method proposed, durability/environmental fatigue experiments of RC beams strengthened with carbon fibre laminates (CFL) were carried out including the following four experiments: a) non-interaction experiments (the current method) of constant temperature, constant humidity and fatigue loads, b) interaction experiments of constant temperature and humidity and fatigue loads, c) interaction experiments of real service environment and fatigue loads, d) interaction experiments of real service environment and vehicle random loads. The results showed the durability/environmental fatigue experimental method proposed by this paper was effective and feasible.

In this paper, the programmable logic controller (PLC) produced the steam cleaning machine controller based on PLC and foundation design, and steam cleaning device controlled the process of the realization .The programmable logic controller PLC programming and logic design, system realizes according to different artifact types, complete cleaning, blowing, drying the corresponding action. This system after careful design, manufacturing and detailed inspection, and after the running test, the experimental results shows that: as long as the proper maintenance and proper use of equipment, the project can improve the efficiency to a great extent.

Grounding grid was considered as a pure-resistor network and its inner information was obtained through limited grounding leads. A set of diagnostic equations was established based on Tellegen’s theorem. Iteration method and Nonnegative Least Squares method (NNLS) were used to solve it. To verify this method, corrosion diagnosis of single-branch and two-branch was simulated. An optimal plan was proposed in the simulating calculation, which diagnosed step by step and added measurement nodes according to the result of each step. This method is able to determine the corrosion position and degree reliably and the optimal plan has higher efficiency and less workload.

The quality of oil determines the status and life of the devices. However, most Chinese vessels have not equipped with on-line oil quality testing facilities. Therefore, a special on-line oil quality monitoring system for vessels is designed to real-time monitor of oil pollution change. An alarm signal or control signal based on the monitoring results is sent, which supports the purifier automatically and water, particles and gases are removed from the oil to maintain a good oil quality. The system is developed and implemented in the vessel corporation and has a good prospect of application. The application of this system will promote the process of the intelligent device management.

Minimum variance distortionless response (MVDR) beamformer is a better target detection method, which provided high-resolution and anti-interference abilities. But the nice features will be degraded significantly for a fast bearing-rate target. Because the eigenvalue of longtime integral correlation matrix will spread, the signal and interference are no longer clearly identified by the eigenvectors. A beam domain MVDR and motion compensation arithmetic is given in this paper. The motion effect can be compensated by tracking the signal bearing change using real time estimated beam domain covariance matrix. The detection ability of moving target can be improved.

In the salvage process, data about the shape of shipwreck, sink sitting posture, buried degree and other related information should be required in order to develop salvage program. Three-dimensional imaging sonar is used to provide such data for salvage work by underwater acoustic detection and three-dimensional imaging technology. An application example is described and the results show the effectiveness.

A Magneto-rheological Fluid Clutch (MRC for short) which has a novel and simple structure is designed; the research on the magnetic field distribution is based on the finite element simulation software which is named Ansoft; In order to test the work performance, the electronic torsion testing machine is used for the torque transmission capability and controllability test. The experimental results reveal that the MRC could meet the torque transmission demand of high power machine and response quickly and reliably.

In order to realize the mine water source identification and to prevent water accidents, taking Xinglong Zhuang coal mine’s lower group coal mining as an example, based on the analysis of mine hydrogeological conditions, the mine water source identification system was designed by using the software of MapObjects powerful spatial analysis ability and Bayesian classification analytical method. The software can achieve mine water source identification and provide a certain basis for mine water disaster prevention and control.

Digitizing architecture of band-pass sampling at IF(Intermediate Frequency) is a kind of software radio structure of high practical value. One kind of application in the digitizing architecture of band-pass sampling at IF of RF (Radio Frequency) front-end hardware is designed in this paper. The experimental results show that this kind of RF front-end has great practical value and research significance.

This paper introduces an overview on services and functions and the process of connection reestablishment provided by the RRC sublayer in the E-UTRAN of the LTE system. Then describe the process of connection reestablishment in detail. It also provides the specific designed flow chat to explain more exactly.In the design process,it simplifies signaling interaction between layers and the corresponding process is optimized and improved combined with the specific characteristics of major projects and the failure of connection reestablishment is analyzed in brief. Finally, the GFT chart was generated to verify the correctness of TTCN co-simulation.

This paper addresses the observability problem of 2D Multiple Autonomous Underwater Vehicles (MAUVs) cooperative navigation system. We derive the conditions to keep the local weak observability of navigation system using the Lie derivatives, and characterize the unobservable trajectories of AUVs. We design a series of simulation experiments using the Extended Kalman Filter (EKF) to verify the theoretical results. Finally, the simulation results show that the good performance of navigation system can be presented if avoiding the unobservable trajectories of AUVs.

This paper presents and implements an automatic roaming and fast virtual endoscopic neurosurgery system for transsexual approach, which can be compatible with the fiber-optic endoscopic transnasal approach in the skull base surgery, and accurately locate the position and their mutual relations among the lesions, tumors and surrounding vital anatomical structures. The system uses a multithreaded RayCasting volume-rendering algorithm based on the graphics processor (GPU). It reconstructs the nasal three-dimensional structure in the skull base surgery, and optimizes the centerline extraction that can be carried out automatically. In real-time display, it improves the translucent rendering optical model, taking into account lighting model important parameter - the image gradient translucent degree of non-linear effects, and can fully display the skull surface and internal implied the interface and internal details.

LTE is accepted worldwide as the Long Term Evolution Perspective for todays 3G and 4G networks. Cell search time synchronization is an important physical layer procedure by which a user equipment (UE) acquires synchronization with a cell and detects the physical layer cell ID of that cell. Timing synchronization is consisted of the symbol timing synchronization and frame synchronization. This paper supplies the introduction of synchronization signals, presents the detection method, and analyzes the design based on FPGA platform and finally simulated on the Modelsim 6.5 and implemented in Xilinx Virtex-6 kit.

At the pyrolysis temperature range of 460°C to 560°C, the pyrolysis of Wulagai lignite and the acid-washed lignite is completed on the fixed-bed reactor. The phenols are detected by GC. Study shows that the minerals in coal may influence the decomposition of the phenols intermediates or suppress the producing of final phenols, acid-washing helps improving the yield of phenols. The minerals in lignite have no effect on the generation of low boiling-point phenols in the lower pyrolysis temperature, but have significant effect on the yield of high boiling-point phenols. The minerals in Wulagai lignite have a significant effect on the distribution of the fixed bed low temperature pyrolysis phenols.

This research investigated on reducing carcinogenic polycyclic aromatic hydrocarbons(PAHs),especially benzo[a]pyrene (BaP) in coal tar pitch by modifying with the two selected modifiers: Paraformaldehyde and Epoxy Resin. The reaction emphasis on the change of temperature, reaction time and the quantity of the modifiers. The results indicated that Paraformaldehyde and Epoxy Resin could decrease the PAHs content greatly. The BaP decreasing rate reached 75.86% and 53.45% respectively. And the BaP equivalency content of the pitch decreased from 2.94% to 1.41% and 1.47% respectively. The properties of the modified coal tar pitch, including soft point (SP), toluene insolubles (TI), quinoline insolubles (QI) have changed a lot.

In this paper, the pyrolysis of Honehe Lignite in N2 and N2-Methanol atmospheres were investigated on a fixed-bed reactor. The methanol flow rate, pressure, temperature and holding time were studied. The maximum of coal tar yields 12.01% (with methanol injected in) and 9.61% (absence of methanol) were achieved on the conditions of 520°C, 0.5MPa, N2 flow rate 50ml/min, methanol flow rate 0.1ml/min and holding time 20min, and the relative growing rate was about 25.0%. The gas from coal pyrolysis was detected by GC, and the coal tar was reprocessed and then detected by GC-MS. While the solid char was detected by IR to study the change of oxygen functional group during coal pyrolysis in N2-Methanol atmosphere. Compared with that pyrolysis in N2 atmosphere, the components, characteristics and properties of coal tar, gas and solid char varied a lot. The results showed that the injection of methanol into the system changed the products yields and distribution. The results showed that the total yields of phenol, cresol and xylenol (short for PCX) in the Acidic were about 1.93% and 1.15% (daf) in two atmospheres respectively, the PCX yields with methanol injected was about 1.67 times higher than that absence of methanol.

With heavy mass and free falling body movement, the hammer is very dangerous and unstable during testing, so testing machine by the component systems of the research, designing a security system,including the mechanical structure of the safety design and safety of electrical control system design. In particular, the safety raising and releasing mechanism is designed to enhance the use of friction to achieve self-locking latch device functionality, so pin lock to prevent accidental operation errors will pull out, hammer will not be down. During the experiment, system have a good protection.

In order to research the influence of the main parameters of Dual Mass Flywheel to the torsional vibration of the transmission system, one heavy vehicle was taken as the target vehicle and its dynamics models of transmission system in the idle conditions and the driving conditions were established by ADAMS.Then the main design parameters of Dual Mass Flywheel were gained through simulation and optimization.Finally,a new Dual Mass Flywheel,whose vibrating springs are distributed on both sides of the damping disc,was designed and its damping effect was studied through simulation research.

This paper makes a study of design of mix proportion of leaf concrete. In the experiment orthogonal design scheme is used to analyze the effect of category of cement, variety and grain size of leaves, variety of superplasticizers, and ratio of water-binder ratio (W/B) on the fluidity (diffusivity index) and the 28-days’ strength of leaf concrete, and had found the primary and secondary order of the influence of the above-mentioned four factors on the index, thus laying a reasonable basis for further development and application of leaves in the field of heat insulating and building materials.

An analytical method was presented on some pairs of gear teeth contacting each other at the same time. First, the software Pro/E is applied to establish two kinds of gear whose fillet curves are typical double circular and single circular respectively. Second, changes of meshing locations is made to get omni-directional contact analysis results. At last a conclusion was drawn that bending stress on dedendum double circular gear is 1.3~1.5 times bigger than that on dedendum single circular gear,that is dedendum single circular gear has better carrying capacity. The study provides a good method for studying gear bending stress.

Organo-montmorillonite (OMMT) was compounded with Hydrogenated Nitrile-Butadiene Rubber （HNBR）(50% epoxidation) to prepare nanocomposites by melt mixing method. The nanometer scales of organoclays in rubber matrix were determined by X-ray diffraction testing, the exfoliated/intercalated structures of OMMT in HNBR were confirmed by transmission elector microscopy. The increases in tensile module and strength of HNBR/OMMT nanocomposites vulcanizaters were caused by the better interactions between rubber macromolecule chains and organoclay layers. The air-aging properties of nanocomposites enhanced by the increasing content of OMMT, which was leaded by the barrier characterize of nanodisperse OMMT layers. DMA test showed that the Tgs of HNBR/OMMT shifted to a higher temperature, as verified by the crosslinking density determination.

To speed the domestic research on double pulse motor,and specify the research direction,analyzed the pulse separation device (PSD) of external double pulse motors,classified them according to certain characteristics,expounded research status of domestic double pulse motor,pointed out problems in the study.With the future needs of the missile force,proposed suggestions of future development for domestic research on double pulse motor,and specified the research direction of it.

Rubber/Ca-montmorillonite (Ca-MMT) nanocomposites with exfoliated Ca-MMT layers was prepared by a new preparation method named masterbatch method, in which the masterbatch was prepared by co-coagulating nature rubber latex and bis [3-triethoxysilylpropyl-] tetrasulfide (TESPT) modified Ca-MMT aqueous suspension and then the masterbatch accompanied with carbon black (N220) were used in the system of SBR and ENR. The properties of TESPT in-situ modified Ca-MMT were investigated by Fourier-transform infrared spectroscopy and thermogravimetric analysis. The results showed that the TESPT has reacted with the surface groups of Ca-MMT. The dispersion of the Ca-MMT in masterbatch and vulcanized sample was characterized by X-ray diffraction. The results showed that in the masterbatch an exfoliated structure was obtained and in the vulcanized sample a coexistence of intercalated-exfoliated structure was obtained. The influence of the Ca-MMT loading on the structure and properties of the nanocomposites were studied. It was found that the incorporation of Ca-MMT hindered the vulcanization, improved mechanical properties, thermal properties and aging resistance properties. The dynamic mechanical analysis results showed a decrease of tanδ max when the Ca-MMT is added.

The elevator control system is an important component of the modular elevator control system. The control and profile and PWM-pulse pattern generation are done by a microprocessor system. Position recognition, security and motor/inverter protection functions are implemented. Furthermore the microprocessor system has to establish the communication via the serial link (Multidrop protocol) with the motion command subsystem, from where it gets the door commands.

Wuhan Junshan Yangtze River Bridge is an important traffic hinge on Jing-Zhu freeway, it is very necessary to conduct the comprehensive and systemic investigation on the bridge aseismic. In this paper, the FEM model of it was established; the dynamic characteristic and nonlinear seismic responses under uniform and non-uniform excitations of it were systematic studied. The results show that: 1) the basic cycle of Wuhan Junshan Yangtze River Bridge is about 8.881s. Its first mode of vibration is longitudinal floating mode, which is favorable to the earthquake- response of structures. 2) Its former 40 rank frequency are located between 0.1~2Hz which is avail to the condition of traffic condition.3) the geometric nonlinearity has much influence on the response of this kind of bridge.4) the seismic responses are sensitive to the frequency spectra of the input earthquake wave. 5) The traveling wave excitations are unfavorable to the design of tower and the main girder when considering the three orthogonal seismic wave input. In order to get correct results, artificial seismic wave of the bridge address is necessary to the time-history analysis.

Since the traditional design methods are based on the simply-supported experimental model, the bearing capacity of concrete bridge deck reinforced with GFRP bars is often determined by serviceability limits. The predicted bearing capacity is so low that high reinforcement ratio and construction cost are lead to. However, the previous researches on concrete bridge decks reinforced with GFRP bars revealed that crack widths and deflections were far less than the predictions by traditional codes, due to the existing of compression membrane action. This paper proposes a restraint test model to stimulate the comprehensive working property of deck system，considering the restraint from other part of the deck. Compared with simply-supported test model, bearing capacity and serviceability of the proposed are improved by more than 1 time. New experimental model for designing concrete bridge deck reinforced with GFRP bars are required.

This paper provides a good method to improve the safety and reliability of elevator logic system. It uses watchdog timer to prevent code-execution errors, 3-phase sequence detector to check for an incorrect phase sequence or missing phase voltages, and DC brake current sensor to measures the flow of current through the brake coil to avoid any damage on the drive-brake system.

The car weighting test system provides a good method to improve the comfort felt in car by passengers. It uses force sensors to measure the car load based on a optics-mechanical system that measure the displacement of an steel part which is proportional of the applied weight force.

The brake release electrical control board is a very important element of the elevator rescue operation control system. The brake release board provides a power supply to operate an elevator brake by a battery in rescue operation mode to allow a motion of a car until the next floor level to release any passengers. The brake release board has some buttons to operate the car and some LED’s to indicate the state of running. There are also some parameters in the board to adjust the operation.