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A design and simulation for L-shaped slot microstrip line antenna with semicircle defected ground structure has been researched, the main purpose is suppressing the existence of higher order harmonic. In this paper, simulated soft (Ansoft HFSS V.6.0) used to be simulated the frequency response under different parameters such as dimensions, amounts of SDGS. The results show good performance of SDGS in higher resonant frequency suppression. Final, an antenna with 2.4GHz center frequency had been design and fabricated.

A design and simulation for low pass microstrip line filter with defected ground structure has been researched, the main purpose is with the simplest method to design an ideal low pass filter. In this paper, simulated soft (Ansoft HFSS V.6.0) used to be simulated the frequency response under different geometric shape of DGS. The results show good performance of a low pass filter with DGS. Final, a low pass filter with DGS design and fabricated, The properties are shown as flow: center-frequency: 7.28G, S21:-47dB, cut-off frequency: 5.88GHz.

Four series of Mo2FeB2 based cermets with different Nb content between 0 and 6 wt.% had been successfully fabricated by liquid phase reaction sintering (LPRS). The densification behavior, microstructural characteristics and mechanical properties of Mo2FeB2 based cermets were investigated. The result shows that with the increase of Nb content, the grain size decreased, but more pores formed. Meanwhile, the hardness and transverse rupture strength both be increased first and then decreased. Mo2FeB2 based cermets doped with 4 wt.% Nb content have the highest hardness and TRS of HRA 90.6 and 1970 MPa.

A periodic microstructure with dielectric and metal layers is proposed to obtain a bandpass filter. The multilayer microstructure is compounded of ring cross slot and cross slot. The center frequency of the filter is 0.338THz with a 3dB bandwidth of 75.62GHz. The maximum insertion loss in the pass band reaches 0.60dB. The bandedge transitions of the rejection bands are 232dB/THz and 176dB/THz, respectively. Furthermore, the physical mechanism of near field distribution and the influence of two factors (the number of metal layer and dielectric layer) on the passband have been studied. Meanwhile, the frequency response is analyzed for different incident angles and polarizations. The frequency response characteristic is insensitive to the polarization, and a good performance for incident angle of the transmission is obtained. It can be applied to THz atmospheric communication system.

Fault location is an effective way to ensure quickly power recovery after a failure in power distribution system. Bad operation environment of FTU, damaged elements or lost information usually cause variations in fault information for correlation analysis in fault location of power distribution system. A data mining (DM) correlation analysis model based on rough sets (RS) theory and immune algorithm (IA) is proposed in this paper. Firstly, using RS theory to extract domain knowledge, a set of the given variant fault pattern is converted into a decision table in RS. Secondly, an attribute reduction of the decision table is made by using the IA theory, and the intrinsic correlation rules between input vector (condition attribute) and output vector (decision attribute) are mined. Then, the data mining method is used to deal with the distortion of FTU real-time input information. According to the current limit information sequence of section switches, line fault states in each section are judged to realize the fault location in power distribution network. Finally, the feasibility and effectiveness of the fault location model of distribution network based on RS-IA data mining model is verified by simulation.

For the purpose of grasping the stress state, vibration characteristics and safety of the steel arch in Nanjing Olympic Sports Center, which is the main support among the stadium roof system as well as the world's largest oblique arch structure, a real-time health monitoring system was established and the main achievements including the system constitution, monitoring items and layouts of measuring points were described. The monitoring data measured during the 2 years period from 2014 to 2016 as well as the SAP2000 finite element software were combined to conduct the status identification and safety evaluation. The results show that the simulation results are consistent with the measured date; The measured alignment of the large arch is relatively stable, although the structural stiffness of arch has weakened compared with the designed state, the low order vibration frequencies are stable during the 2 years period; The stress state of each monitoring component is at safe levels, and fluctuates within a small range affected by the extreme seasonal temperature changes.

Foam concrete products had high absorption rate due to a large number of bubbles dispersion in it.which has serious effects upon the overall thermal performance of material and the durability of construction.Three methods were studied which includes Organic Silicon hydrophobic agent、High fatty acids hydrophobic agent and hydrophobic agent F in order to reduce the water absorption rate.Results show that the water absorption rate was reduced significantly with mixed High fatty acids. The water absorption rate drops of 68.2%, and the organic silicon is in a second place , and the hydrophobic agent F is the worst.

In order to meet the requirements of increasing domestic airline pilot training and flight safety, airline pilot training departments pay special attention to flying qualities of advanced teaching aircraft. According to the application of equivalent systems in aircraft flying quality evaluation system, the selection method of initial value and equivalent system and the evaluation index of equivalent systems are analyzed. A modeling and simulation example is given to an advanced teaching aircraft, and it increasingly demonstrates that the adoptive equivalent system method applied to flying quality evaluation of advanced teaching aircraft is feasible.

In this paper, we used Lab VIEW development platform, designed a virtual signal acquisition and analysis system based on the soundcard. In addition we studied the signal acquisition performance of it. This system has functions of signal acquisition, analysis, waveform display and storage. It is easy to use with good interface, and function appending is available on user requirement. It offers a kind of DAQ solution with low cost. It has broad application prospect, can be extended to the field of speech recognition, ambient noise monitoring and laboratory measurement etc.

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.

The present study, which is based on the finite element method, investigates the alloy element content assessment of these Fe-Si alloy steel sheets from the view point of eddy current testing. The relative permeability and conductivity were preset parameters. Eddy current signals were gathered by a differential type cylindrical probe and subsequent nondestructive tests were carried out with the preparation of four Fe-Si alloy steel sheets with different silicon contents. The result of the numerical simulation demonstrated that the signal increased with the increase of the silicon content in the Si-Fe alloy steel sheets. And the measured result confirmed the rationality of the application of eddy current testing in the average silicon content assessment.

Uncertainty of parameters like material mechanical properties are traditionally described by probabilistic model, which requires detailed statistical information of parameters limited to obtain in engineering application. In this paper, the problem is solved by using the non-probabilistic convex model that only needs the upper and lower bounds of variables instead of abundant statistical information, which greatly reduces the demand of data and avoids unsafe results caused by the scatter of data. Based on the non-probabilistic convex model, the non-probabilistic interval analysis method is introduced to calculate the creep damage of HK40 high temperature furnace tube and to discuss the influence of operation conditions on creep damage with operation pressure and operation temperature regarded as interval variables. Consequently, the effect of outer wall temperature on creep damage interval is greater at the beginning of furnace tube operation stage. With the increase of running time, the effect of inner wall temperature on creep damage interval is greater and greater, and at the same time greater than that of creep damage interval when the outer wall temperature considered as interval variables. When the operating pressure is treated as interval variable, the upper and lower bounds of creep damage are nearly in a straight line that indicates the effect of pressure change on damage is little. Meanwhile, the life of high temperature furnace tube is predicted according to the definition of non-probabilistic interval index, and the analysis results are compared with the results of probabilistic model. The analysis results sufficiently demonstrate that the non-probabilistic approach presented in this paper is viable.

Under the effects of rapid social-economic development and urbanization, populations dwelling in large community housing buildings have become more concentrated than ever in Taiwan. This might lead to major casualties and property loss if a fire occurs. Therefore, research on fire protection engineering is particularly critical for large buildings. If fire protection engineering considerations are addressed extensively, fire damage can be minimized. This study simulated an actual building fire case of New Taipei City and analyzed the fire field by using the Fire Dynamics Simulator, developed by NIST/USA. In this case, the dwellers of the building had illegally used the patio space to store combustibles. Additionally, the interior of this dwelling contained numerous combustible decorative materials that resulted in a fast expanding fire inside the dwelling. The high temperature smoke generated by the fire moved upwards through the patio because of the stack effect. The dweller had installed a steel window on the opening of the patio illegally, which considerably narrowed the opening and caused the smoke to rapidly accumulate in the patio. This caused the materials inside the patio to burn quickly, and finally resulted in numerous casualties and substantial property loss. The fire characteristics were investigated to obtain transient results regarding influential parameters, such as the temperature of the fire field and concentration of CO, to analyze and discuss the state of the fire field and allowable time for escaping. These results may be applicable for preventing and reducing the future occurrence of such disasters.

For the development of large wind turbines, the approach of trial and error is also not adequate for mass produced wind turbines, a reliability-concerned manufacturing must be involved for the future development. An approach which introduces probabilistic reliability assessment which incorporates reliability methods into wind turbine engineering is described. Fault Tree of wind turbine generators electrical components is firstly built. Then it is transformed to the Bayesian network and probabilistic distribution is preceded using Markov chain Monte Carlo inference. Finally a set of qualitative and quantitative reliability is given according to a specific probabilistic input.

In this paper, a key treatment technology of the culvert foundation is presented, which is on the high salt saturated fine sand in a new China local railway from XieTieshan to North Hobsonis. In the procedure，for the two kinds of culvert foundation treatment technology(gravel pile foundation and rubble replacement), the settlement laws of culvert under China-load are explored by comparing with the field observation data and numerical analysis conclusion. The results show that in saline soil area, using rubble fill to reinforce groundwork is a appropriate treatment technology for culvert foundation.

The poly (ethylene terephthalate)/poly (trimethylene terephthalate) (PET/PTT) blends were prepared and their phase morphology, mechanical and thermal properties were investigated by scanning electron microscopy (SEM), polarized optical microscopy (POM), universal material testing machine, differential scanning calorimetry (DSC), wide-angle X-ray (WAXD), respectively. The glass transition and SEM results suggest apparently that the PET and PTT have good miscibility at amorphous state. The blends with more PET content less likely undergo a melting/recrystallization process during DSC heating scan. In the blends, PET component with higher supercooling degree crystallizes first, and then the crystallites of PET will be the nucleating agents for PTT, which greatly improves the crystallization rate of PTT. Because of the interaction between the PET and PTT, there are much smaller spherulites formed in blends with increasing PET component. The blend with more PET contents has larger tensile strength and modulus.

Wind turbine generator (WTG), with a large inertia in the time-domain, has a significant restraint to the high-frequency fluctuations of the wind speed. When analyzing and modeling the wind turbines electrical and controlling processes, its needed to quantify or estimate this inhibition. To estimate the WTGs inertia parameters, a digital filter is introduced to approximate the inertia transfer model of WTGs blade, drive chain and the generators rotor, by analyzing the correlation of the filters output and the generators rotor speed, the time window with the best correlation probability is selected as the restraint performance indicator of the blade, drive chain and generators rotor. The proposed method is finally verified by the simulation using the SCADA data.

There are a lot of Permian volcanic rocks which are widely distributed in Tarim Basin. Because of the shielding effect of the volcanic rocks to the underlying structure, the distribution of the volcanic rocks in Tarim Basin is very important to the deep oil and gas exploration. However, with the progress of oil exploration in Tarim oil field in recent years, much more logging and seismic data is available. Based on the model of logging-seismic integrated identification, the distribution of the Permian volcanic rocks is revised by using the drilling, logging and seismic data. It shows that the rhyolite is mainly distributed in the north basin, and the basalt is widely distributed in the basin. Moreover, the basalt has larger area than which delineated by other people.

Temperature dependent solid-liquid extraction behavior of eight rare earth elements (REs) was investigated using N-butyl pyridinium hexafluorophosphate ([BPPF6) as an ionic liquid solvent and 8-hydroxyquinoline (HQ) as an extractant at 80 °C. Parameters including the amount of [BPPF6, HQ concentration, extraction time, extraction temperature and pH were investigated and optimized. The extracted species was neutral REQ3 in the RE3+-[BPPF6-HQ solid-liquid extraction system. The extraction percentage of RE3+ could be higher than 99%. The recovery of RE3+ extracted into [BPPF6 can be achieved using the mixture of hydrazine hydrate and ethylenediamine tetraacetic acid as stripping agents. The extraction equilibrium constants and the pH1/2 values of eight REs and their separation factors between adjacent rare earths were estimated and comparatively studied. REs were extracted into solid ionic liquid phase with smaller volume and concentrated to some extent. Furthermore the temperature dependent solid-liquid extraction allows to recover [BPPF6 after the extraction procedures. These results indicate that the proposed procedure can be used for the preconcentration and separation of REs using [BPPF6 with high melting point.

this paper designs a redundant second fall detection device. On the basis of the traditional mechanical press slider second fall detection device, this new type device adds an MCU detection unit independent of traditional PLC system. Using the magnetic rotary encoder to replace traditional photoelectric encoder, realize non-contact measuring angle, which can reduce the probability of component failure. Compared with the traditional second fall detection device, this kind of redundant type second fall protection device can greatly increase the safety performance of the mechanical press.

Digital substations primary equipments make use of many intelligent primary equipment, for example, Electronic Transformers (including Electronic Voltage Transformers EVT and Electronic Current Transformers ECT,which meet the standards IEC 60044-7/8),intelligent switch and so on,digital substations secondary equipments include many IED(Intelligent Electronic Device). This thesis studys on the function,design,hardware and testing method of the testing system for real-time of communication of the digital substations secondary equipments.

During the two surveys at both spring and neap tides in wet (July-August 2008) season, measurements of flow, turbulence, suspended sediment concentration (SSC), fine-grained sediment particle mean diameter (Dm) were carried out over 26 h that covered two M2 semidiurnal cycles in the middle north channel of the Yangtze estuary. The preliminary observations data show complex temporal and seasonal variation in estuarine flocculation of fine-grained sediment. In the high-turbidity and high-energy area of the Yangtze estuary, the flocculation processes indicate that the turbulence shear stress maybe the most important factor to the fine-grained sediment flocculation processes during the spring and neap tide cycle change. There exists a turning point of flocs Dm vs. turbulent shear stress. The neap tidal critical turbulent shear stress is around 0.1 Nm-2, much smaller that the spring tidal data of about 0.5 Nm-2.

PEEK based composites have been increasingly employed as biomaterials due to its excellent biological characteristics. In this paper, the biocompatibility, bioactivity, bio-tribology and biomechanics of PEEK composites were investigated. The results showed that PEEK possesses excellent cellular and blood compatibility. The bioactivity of PEEK could be improved by various techniques such as plasma treatment, surface grafting, surface deposition and addition of bioactive glass ceramic in the PEEK matrix. The results of bio-tribology showed that the biotribological properties of PEEK based composites could be comparable with that of traditional artificial joint materials such as UHMWPE. It is even superior to UHMWPE under certain conditions. The biomechanical properties of PEEK composites showed that they can improve the initial stability, reduce the stress shielding and improve bonding strength between bone and implant after replacement, while they are compared with traditional implants such as stainless steel, titanium alloy and Co-Cr-Mo alloy.

The unequal leg transmission tower in mountainous areas of 5B-ZBC4 is based to establish the finite element model of three transmission tower and four wire line system. To further study the transmission tower under wind load displacement response, firstly using ANSYS analysis of the dynamic characteristics of the tower-line system. Then, taking the power spectrum of Kaimal wind speed and simulating the curve of wind speed of transmission tower line system in mountainous areas, considering the different elevation and different sizes of wind load, to analysis the wind vibration response for the tower-line coupling system. The results indicates that the tower top displacement means of 1# tower, 2# tower, 3# tower is increasing along with the elevation changes in 0 degrees wind load; The 37 m/s is the critical wind speed of 3# tower of transmission tower line system.

The new all-terrain mobile platform can improve the human mobility in non-structure environment, which is mainly determined by the walking mechanism quality. In this paper, the walking mechanism structure is designed, and its working principle is analyzed. Theoretical analysis and parameter optimization are completed during the parameter design of the tracked circle, which verifies the parameter rationality of the self-tension mechanism. Besides, the dynamic analysis of the multi-degree of freedom suspension system is accomplished. The results show that the structure and parameter design of the walking mechanism is available, which provides theoretical basis for the new mobile platform parametric design.

FlexRay bus is considered as a more promising bus in the future with the performance of real-time, scalable, and fault-tolerant. In this paper we will design an electric vehicle battery management system (BMS) based on FlexRay bus, including the hardware design, the SoC estimation method, FlexRay protocol design and software development. The test bench experiment results show the system design is reasonable and feasible.Keywords- FlexRay, BMS, Li-ion battery,SoC, Design

This paper conducted an experiment to research flexural property of SMA unbounded prestressed box beam ,which applied the Shape Memory Alloy (SMA) at martensite state as externally prestressing tendons, and then through heating the SMA bars fully anchored on the beam with cracks by electrifying motivation, drove SMA to produce the “recovery stress” because of transformation, to study the effects of this stress on the deflection and crack width of concrete box-beam on work ,to study the recovery ability of SMA bars ,and to provide basis for the application of the SMA bars to bridge strengthening.

In the performance- based seismic design, seismic performance of building is differently evaluated according to variant seismic conditions. Most of the application programs for structural design (ETABS, SAP, MIDAS, ANSYS etc.) calculate the performance points of building according to Federal Emergency Management Agency（FEMA）, Applied Technology Council -40 (ATC -40)’s seismic building code and parameters. On this paper, we evaluated the seismic performance of building according to our national seismic building code[1] and parameters and maked suggesti- -ons on the design practice.

Currently the settlement and deformation of factory building structure is monitored using total stations and other more conventional measuring instruments, it is difficult to reflect the health of the structure timely and accurately. In order to change the situation, we establish a set of system for real-time monitoring of deformation and safety warning. The system is formed of sensing layer, transport layer and application layer. Sensing layer is composed of static force level and biaxial inclinometer. The system can be used in dynamic real-time factory structure safety monitoring, also applied to other similar structural monitoring. This paper will study the system components and principle, early warning systems grading, calculation of real-time deformation of roof frame, laboratory test scheme and verification. Experiments showed that the system is suitable for the actual factory structure monitoring, while the choice of static force level and biaxial inclinometer of precision to meet the requirements.

A gearbox condition assessment method for the Wind Turbine Generator (WTG) is proposed. Vibration signal’s Intrinsic Mode Functions (IMF) are decomposed by Empirical Mode Decomposition (EMD). Normalized Hilbert-Huang and Direct Quadrature (DQ) method are used to determine the instantaneous frequency. The HHS of vibration signals is plotted and then is shifted to match the pre-defined faulty gear condition by the Iterative Closest Point (ICP) algorithm to diagnose their similarities. The principle and effectiveness of the proposed method are illustrated by simulation, the fault types of gearbox can be identified by ICP algorithm effectively.

‘Sonication - cryptic growth’ technology can reduce 30-80% excess sludge in wastewater treatment systems. Various mechanisms contribute to the sludge reduction but the role of each one is unclear. This paper quantitatively studied the potential mechanisms in ‘sonication - cryptic growth’. The operation condition was: every day 20% sludge was sonicated under 1.2 Wml-1 for 15 min and then returned to the wastewater treatment reactor for cryptic growth. The results showed that under such conditions, ‘sonication - cryptic growth’ reduced the excess sludge by 57.3% and the effluent met the national discharge standard. Multiple mechanisms were involved in the process. Detailed analysis showed that the ‘lysis-cryptic growth’ mechanism was the most important one and accounted for 49.1% of sludge reduction. Biodegradation of residual sludge was the second important one and contributed 19.5%. Other potential mechanisms included the altered microbial community, longer sludge retention time, and accumulation of persistent materials. But organic load increase had virtually no impact.

The variations of daily biogas yields, cumulative biogas yields, biogas composition analysis, total solids (TS) and volatile solids (VS) were studied in the process of mesophilic and dry anaerobic digestion of food waste under different oil contents (0%, 2%, 4%, 6%, 8%, 10%) at 35 °C. The gas production raised and then went down with the oil content, followed by 243.14, 245.64, 256.09, 269.25, 276.54, 284.22mL /g TS respectively. The research provided a reference for the pretreatment of food waste in follow-up continuous fermentation. Results showed that the period of the process of mesophilic dry anaerobic digestion under oil content of 0% was the shortest, with the total biogas production of 1275.5mL. During the process of the digestion, methane content of the biogas raised and then went down, up to a maximum of 77.62%. The removal rate of TS and VS in food waste with the oil content of 6% was the highest, obtained as 11.2% and 13.2%, respectively.

Waste frying oil is abundant and can be used as a cheaper carbon source in PHA production. The utilization of waste frying oil for production of PHA not only enhances the economics of such products,but also provides with a strategy to overcome disposal problems. In this study, the waste frying oil is used as the carbon source for the synthesis of PHA by Cupriavidus necator (formerly known as Ralstonia eutropha) to find out the best growth conditions in order to provides the basis for producing PHA in industry. The results showed that the optimal conditions for production of PHA was at the temperature of 25°C, pH 7, C/N ratio (w/w) 20:0.75 and incubation time 72h. The maximum concentration of PHA was obtained as 7.04g/L.

An Unmanned Aerial vehicle (UAV), commonly known as drone, is an aircraft without a human pilot aboard. In recent years, some UAVs are deployed for civil applications, such as policing, firefighting, air pollution monitoring, and aerial search and rescue, etc. Unmanned Aerial vehicle generally include fixed-wing and multi-rotor aircrafts. This research had developed a high endurance quadcopter for search and rescue mission. Target position correction software also was developed in this research. This program uses GPS coordinates embedded in the EXIF information of the aerial photos and more accurately calculates the target’s position. The target’s position error is less than ten meters in 75 meters altitude. Keywords: target position correction software, search and rescue, UAV, quadcopter, and GPS.

During seismic hazards, offshore wind turbine structures do not have direct effects on people's safety; however, the seismic design is still important to prevent heavy damage on structure. The seismic design of offshore wind turbine has been discussed in some previous studies. Based on the result of those studies, we further modified the seismic source, especially on active faults in west foot hill zone. Of all the active faults in this area, we choose five which lie nearby the sites to make the modification. A logic tree has been set to avoid overlapping and derive an accurate recurrence model of the seismic source used in PSHA. This study is just a preliminary result of PSHA in wind turbine sites, Chunan and Chanbin, there are still several adjustments need to be done.

Generally after a cylindrical steel bar is made from hot forming process, its contour will look like ‘U’ or ‘wavy’ topography. The preformed steel bar after steelmaking process needs to remove the outside oxide layer by lathe or peeling machine (commonly known as stripping). As a consequence, the deformation of steel bar will cause subsequent problems, such as eccentric rotating of steel bar as the lathe is running. Although it is necessary to remove the oxide layer, the deformation will increase waste materials. To prevent the problems, a straightening machine is usually used to straighten the cylindrical steel bar before the pickling process. However, most current straightening machines cannot measure cylindrical steel bar contour on-line instantly. This study proposed a test method for measure the contour of a large cylindrical steel bar based on multi-line structured light and machine vision. Break line method were performed to measure the contour of the cylindrical steel bar. The experimental result shows that the measurement error is in the range of ±0.4 mm after calibration. The study result concludes that the proposed method can be applied to straightening machine for real-time online measurement to improve straightening efficiency.

Edge cracking is a commonly observed phenomenon in cold rolling process, but researchers appear to be far from fully understanding its failure mechanism due to the complex stress conditions of steel strip under the rolling condition. In this research, the shear modified GTN damage model coupled with Nahshon-Hutchinson shear damage mechanism was applied to investigate the damage and fracture behavior of steel strip in cold rolling. The results show that the shear modified GTN damage model is competent to predict the damage and fracture behavior of steel strip in cold rolling. By comparison to the cold rolling experiment, it presents that the prediction of edge crack occurrence of the shear modified GTN damage model is more accurate than that of the original GTN damage model.

In order to improve the vibration isolation performance of engine mount, a new type of magneto-rheological semi-active mount with multiple inertia tracks is designed based on the existing magneto-rheological semi-active mount . The mechanical model is established according to the mount. The expression of the dynamic stiffness and damping lag angle is deduced, then the dynamic characteristics is simulated in the simulation software. At the same time, verify this model correct by the experiments.

As the sensing element and a driving element for vibration control using smart materials, the structural vibration control is very active field for research and application. This paper mainly study the characteristics of piezoelectric self-sensing vibration .Through the action analysis of research on Piezoelectric Actuator establish a self-sensing piezoelectric vibration damper and a model of self-sensing piezoelectric absorber . Then through the experiment and simulation, get the study on its characteristics.

The upper and lower courses of sea oil and gas exploitationare connected by submarine pipeline which is called life line project. Free span often occurs because of the unevenness and scour of seabed, and fatigue is one of the main failure modes.In this paper, with the finite element numerical simulation method, based on the harmonic response analysis, the research on the structural response of free span under the vibration induced by vortex was investigated, and the effect of the factors such as flow velocity, length of free span. According to the analysis results,the fatigue life of free span was evaluated.

Trisilanolisobutyl polyhedral oligomeric silsesquioxane (TSI-POSS) with the humping semi-enclosed cage structure, was incorporated in concentrations of 7, 13 and 22 wt% into 4,4’-methylenebis (phenyl isocyanate) (MDI) and glycerol propoxylate to prepare TSI-POSS/PU hybrid composites, respectively. The polymer chain characteristics of these composites were investigated by wide angle X-ray scattering (WAXS) and molecular dynamics simulation approach. The results indicate that with TSI-POSS concentration increasing up to 22 wt% in hybrid composites, due to the humping semi-enclosed cage structure, distinct crystallite clusters are formed which lead to the micro-phase separation in composites. Meanwhile, the mobility of TSI-POSS cores and backbones in PU composites has been evaluated by the mean square displacement, which confirms that as the concentration of TSI-POSS increasing, the mobility of polymer chains are restricted apparently. Furthermore, it also indicates that the incorporation of TSI-POSS is as the rigid core in hybrid composites.

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.

Reasonable determination of entire layer or sublayer mining method is the key factor of safe and efficient mechanized caving mining of 14.0～28.0m ultra thick seam , numerical simulation on the entire (sub) layer coal caving mining by the FLAC3D , studying the stress and displacement variation of overburden strata , combining the underground pressure theory , comparative analysis on the calculation results . The results show that entire (sub) layer mining roof stress , movement contours are presented in a semi-elliptical arch morphology , indicating the existence of a high arch structure overburden formations , mining process appears roof tensile destruction , but the entire layer caving tensile stress intensity is lower than sublayer caving . When advancing the same distance , entire layer caving puts a greater impact on the overburden strata than the sublayer caving , has some features such as big range of influence and extent , small roof pressure , lead abutment pressure forward from grand , short time of achieving full extraction , etc.

Fish Swimming in MPF (Media and/or Paired Fin) mode has unique hydrodynamic characters and special application in resource exploration underwater. Inspired of the flexible shape and motion of undulating fin of “Nilotic Ghost” fish, a Hydraulic-driven Bionic Undulating Robot (HBUR) is developed and studied in the paper based on CFD method, to investigate the flexible characteristics of shape adaptation and hydrodynamics of HBUR fin, which has great significance for the propelling safety of HBUR underwater. In this paper, a mathematical model is brought forward to indicate the undulating motion of HBUR, which is formed by sequentially and periodically swing motions of Hydraulic Swing Actors (HSAs), and then the CFD method is introduced to calculate the hydro-forces when undulating shape of HBUR fin are distorted, because of distraction underwater. Results show that HBUR could produce propelling forces even when some of the HSAs are restricted from swinging, and shape adaptation ability of different part on HBUR fin is different, where the middle part is worse than the two sides. The propelling forces generated by undulating motion the rest of HBUR fin could be used to get the underwater robot out of trouble itself, and then undulating shape will restore to normal state.

This paper aims at the problems of safety and efficiency of airport,designs and implements an Advanced Surface Movement Guidance and Control System (A-SMGCS) terminal, discusses the goals and key technologies about the system,including cache design of aircraft targets, and efficiency improvement of a large number of targets on the aerodrome.Finally,we give the test and conclusions of the system at a international airport in China.

Context aware computing is important for applications to provide smarter and saferservice to mobile users, especially when users’ context changing rapidly or regularly. In this paper,we propose a context aware model for mobile devices based on audio and location. The informationcan easily obtained from sensors, e.g., microphones and GPS. Thus, exploiting the MFCC featuresand the location, a Bayes Net is trained and built and will be used for context classifying in thereal-time classification. The results of experiments implemented on Android 4.0 platformdemonstrate promising performance, which indicates that the model is able to support realapplications.

Corona cage is an important supplementary method for studying corona phenomenon, which is an indispensable for designing transmission lines. In this paper, the bundle conductors are chosen as research objects and the charge simulation method (CSM) is applied to build calculation model, using line electric charges to simulate bundle conductors, walls of corona cage and space charges. The method of tight coupling of electric field and potential is first introduced in corona processing, in which the Kaptzov hypothesis is directly applied to establish equations of charge - electric field and charge - electric potential. In addition, in order to analyze the capacitance value variation of corona cage when corona onset occurs, the emission, migration and composite process of space charges is simulated. Finally, 4, 8, 12 conductors in corona cage under different meteorological conditions are modeled, and the research results are analyzed. This research can also be applied to model corona cage and high voltage transmission lines at different voltage levels and different bundles under different meteorological conditions.

To realize the on-line quick analysis of the steady-state stability margin for the weak section of a power grid, a method of dividing the important generator groups according to the impact of the system equivalent impedance on the static stability limits of the section is presented. By using the dynamic information provided by the Wide Area Measurement System (WAMS), the center of inertia (COI) of the section of the two sides system is determined. Then the steady-state stability limits of the transmission section and the static stability margin can be calculated. The algorithm is verified by taking the out-play cross-section of West Inner Mongolia as an example, the results show that the static stability power limit and the steady-state stability margin of the section can be obtained accurately according to the presented algorithm. This algorithm can provide an effective analytical method for the online static stability security analysis of a power system.

We present an automatic method to identify cataclysmic variable stars (CVs) in the ninth data release of the Sloan digital sky survey (SDSS). The data mining technique is employed and the massive spectra are identified quickly and efficiently. The high dimensional spectra are mapped to feature space constructed by the principal component analysis (PCA), and dimensionality reduction is carried out accordingly. Massive SDSS spectra are classified by the support vector machine (SVM) and most of the non-candidates are excluded. The final greatly reduced candidates can be identified manually and easily. Experiments show that this data mining method can find CVs from the SDSS database in an effective and efficient manner. In addition, this method is also applicable to mining other special celestial objects in sky survey telescope data. We report the identification of a new CV with spectra. The newly found CV enriches the CVs spectral library and will be useful to the research of binary evolution models.

This article, according to engineering geological exploration and mapping data of landslides, describes the characteristics of the typical landslide in eastern Menyuan Basin, including the main landslide body, the surface of rupture and the base of the landslide. And then, through applying GEO-SLOPE finite element software, the evolvement process is analyzed by simulating the formation of dynamics mechanism.