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Direct force method based on finite element for the calculation of the internal force of cross section has the advantages of high accuracy and stability. However, the method can only be applied to the sections with element boundary surface, which limits the application scope of the method. Given the advantages of direct force method based on finite element in calculating the internal force of cross section, a new approach for calculating internal force of cross sections in any location is proposed in this study. In this approach, the inverse isoparametric mapping and the direct force method based on finite element are combined together to solve the internal force of cross section at any location in a finite element model.

In order to make a rational planning of CAPP-PPC process, the differences of product serial and concurrent CAPP-PPC process were studyed in this paper. Based on Witness, Three kinds of product serial and concurrent CAPP-PPC process simulation model were established for products with different complicated degrees. Simulation results show the time of concurrent process is much shorter than serial process, for complex products, especially obvious.

The working performance of gravity dam with an anti-arch shape differs from that of conventional gravity dams. To understand the working performance of anti-arch segments on the bank slope of Xiangjiaba dam, linear and non-linear finite element methods were used to analyze the deformation, stress as well as the state of transverse joint and cracks during the operation period. The coefficient of anti-sliding stability of each dam segment and the safety degree of dam body were also calculated. The results show that under the conditions of non-grouting of transverse joints and well grouting of cracks, the deformation rules are consistent for all segments investigated and accord well with that of the conventional gravity dam. Both the dam heel and dam toe are subjected to compressive stress. In the cold seasons, there is a tensile stress region on the top of the dam body, where the tensile stress is smaller than the tensile strength. The transverse joints are opened, while the cracks are generally closed under compression and stable on the whole. The anti-sliding stability coefficient and the safety degree of each dam segment are above 3.0, which satisfies the design code.

The differences of development cycle between product serial and concurrent development process are obtained through simulation in this paper, which implies the importance of rational planning in the process of product development. The models of product serial and concurrent development process are built based on witness. Three types of models for both simple and complex products have been made respectively to simulate ,and then compared results have been got under six different conditions . Among six situations, the results of four are that the time of concurrent process is much shorter than that of serial process; one is that the time is very close; another is that concurrent process is much longer. We draw a conclusion that product development process must be rationally planned in order to shorten the development cycle for some complex products.

The advantages of high energy efficiency and economic benefit promote the wide application of combined heat and power system (CHP) based microgrid. Firstly, a mathematical model of the CHP based microgrid is developed. Then, a cost function for the coordination of heat and electric load is proposed. Finally, an optimal dispatch model is developed to achieve the economical and coordinated operation of the CHP based microgrid system. Simulation results verify effectiveness of the proposed dispatch model, which is a powerful tool for the energy management of CHP based microgrid with renewable energy resources.

LaF3nanoparticles were used as an additive to improve tribological performance of base oil stock. Their surface modifiers were prepared by a precipitation method, using two kinds of salts from dioctyl-dithiophosphoric acid and piperidine or di-(β-ethoxyl) stearamine. Morphology and structure of LaF3nanoparticles were investigated. The tribological behaviors of these solid-containing lubricating oils were measured by using a conventional four-ball machine. Wear scar surfaces on the test steel balls were examined by instrumental analysis to elucidate the anti-wear mechanism.

A compounded deacidificant was used for deacidification of domestic Bei-Jiang crude. In this work, its formulation was optimized in detail. Effect of reaction temperature, time and the ratio to crude oil was examined. Acceleration by using ultrasonic irritation in deacidification process was investigated. Our results revealed a deacificant composed of ethylene glycol as neutralization agent and cyclohexylamine as extraction solvent not only provided an excellent deacidificcation extent, but also no emulsion problem appeared. 30% cyclohexylamine-containing ethylene glycol solution has the best performance. Deacidification extent reached 85% and higher at a solvent and oil weight ratio of 15%.Ultrasonic wave played an accerleration role, resulting in a shorter reaction time. Naphthenic acids and solvent components were recovered by using vacuum distillation.The recovery rate for solvent components were 99.3% for ethylene and 96.6% for cyclohexylamine respectively. The purity of recovered naphthenic acids was rather high, reaching a acid value of 167.

We attempt to optimize the structure of double web on aviation herringbone gear with a big transmission ratio. We established an optimization mathematical model of the big aviation herringbone gear web, developed an optimization calculation procedure based on APDL language. The web structure of big aviation herringbone gear in a helicopters main gearbox has been optimized. We calculated the dynamic response of the gear web before and after optimization and proved that our method can improve its dynamic characteristics, reduce its stress level and achieve good results.

To simulate the numerical test of concrete, the random aggregate model according to the Monte Carlo method and Fuller Graded Formula is carried out based on the assumption that the concrete is a multi-phases composite material composed of matrix. By adding the function of tracing the propagation of cracks,the Numerical Manifold Method proposed by Shi Genhua is developed which can simulate both the discontinuity of block system and the tensile or shear failure of intact block. The random aggregate model according to the Monte Carlo method and Fuller Graded Formula is carried out, and the concrete fracture process is simulated by the NMM. The strength and failure pattern are in good agreement with the experimental data, which shows that the method put forward and the program developed in this paper can effectively simulate the fracture process of concrete composed of multi-cracks.

Seven reinforced recycled-concrete beams were tested to study their flexural resistance considering the variations of the strength of recycled-concrete and the reinforcement ratio of longitudinal tensile rebar. The aggregates of recycled-concrete comprised the machine-made sand and the recycled coarse aggregate. The failure state of normal section and the flexural resistance of reinforced recycled-concrete beams affected by the strength of recycled-concrete and the reinforcement ratio were discussed. The results show that the failure states of reinforced recycled-concrete beams were similar with those of the ordinary reinforced concrete beams. The flexural resistance was controlled by the reinforcement ratio, and influenced increasingly by the strength of recycled-concrete with the increase of reinforcement ratio. The failure resistance of reinforced recycled-concrete beam can be calculated by the method for ordinary reinforced concrete beam specified in current design code GB50010-2010.

The operational performances of coastal wind farms, located at the east coast of Jiangsu Province of China, are reported in this paper. The result shows that although a rich wind resources predicted in this area, a strong variation of wind resources characteristics are observed between wind farms. Annual averaged wind speeds of five wind farms at hub height range from 4.8 to 6.6 m/s. In addition, the wind shear coefficient shows largely different although they appear to agree with coastal region characteristics. Ru Dong not only has the highest wind shear coefficient but also a largest range of wind shear coefficient variation amplitude. The Capacity Factors of the selected wind farms range from 16% to 27%. Ru Dong shows a lowest Capacity Factor of 16% which may due to the low average wind speed and high wind shear coefficient. On the contrary, Da Feng has a lower Capacity Factor with sensible wind resources indicating either an improved wind turbine technology or an optimized wind farm operational maintenance is needed to increase wind farm efficiency. The result obtained in this paper provides valuable information for future offshore wind farm development in China.

Dangerous rocks are among the most significant factors in analyzing the stability of high slopes, and are the main geological hazards on such slopes. These rocks are typical spatial blocks. The unstable failure of dangerous rocks poses evident spatial features. Consequently, their stability should be calculated by considering it as a three-dimensional (3-D) problem. In this research, the general block method of fractured rock mass and 3-D discontinuous deformation analysis (DDA) are used to study the stability of dangerous rocks on the slope of a hydropower station. The general block method of fractured rock mass is used to generate dangerous rocks and to assess the geometric mobility of blocks. The progressive unstable failure of dangerous rocks is also analyzed. Moreover, 3-D DDA is implemented to examine the stability of dangerous rocks, including the regularity of their unstable failure. The failure sequence of each batch of blocks estimated by general block theory is the same as that in the results of 3-D DDA. The decrease in the shear parameters of the structural plane shortens the time interval of failures, but increases the number and capacity of blocks.

Focus on the working condition of extra-large ore carrier, analyze the necessary means of communication on this kind of ship, based on Iridium satellite communications advantage, builds the Iridium phone system as a complement to the communication on ship, to ensure the safe operation of ships.

According to engineering implement, the elastic element of the rubber isolator is easy prone to fatigue tearing, the model of the pump group floating raft vibration isolation system is established by ADAMS and the finite element ANSYS software, the force distribution of the system is calculated in the different swing angles in ADAMS, and the main reason of the elastic element fatigue tearing is found. Then, the strain change rule of the elastic element is researched in ANSYS, the elastic element which is the most vulnerable to fatigue tearing and its crack location are found, which plays an important role in solving the fatigue tearing of the rubber elastic element in the engineering practice.

In order to realize continuous detection of rail short wavelength irregularity and improve its detection precision, a new four-point method based on chord reference method is derived and presented. Then a simulation waveform consisting of 10 random sine waves has been used for scientific determination of the three separation distances. The new method’s automatic recovery program is developed by MATLAB. The restored waveforms are compared with the results from RMF-2.3E devices and thus the detection precision is achieved. Results show higher detection precision and reliability by over 87% relative percentage comparing to the traditional three-point method, which shows the great applicability and superiority of the new method.

In this paper, a numerical simulation model based on discrete element method (DEM) has been developed to analyze the burden distribution in the Melter gasifier of COREX process. The burden trajectory, the location and the burden surface profile are analyzed in the top charging of melter gasifier. The distribution of ore and coke and the porosity in the radial direction are given under the different charging mode. The results can be used to optimize the charging patterns in order to obtain the reasonable gas distribution.

Phosphorus is the key restraining factor for algal growth and water eutrophication, which is a global problem of environmental pollution. Using a sequential phosphorus extraction method, the phosphorus forms in sediment and their distribution from different trophic area of Taihu Lake (China) and their temporal changes were studied. Results showed that, concentration of Fe-P in sediment was the highest and successively Al-P, which was much higher than that of Ca2-P, Ca10-P, Ca8-P and O-P. All the phosphorus forms were more abundant in sediment 16# of eutrophic lake area, higher than that of moderate eutrophic and the lower-grade trophic area, with the last as relatively the lowest. Phosphorus concentration in June and September was much higher than that of March. Phosphorus in sediment of Taihu Lake had great releasing potential to the overlying water.

The work in the paper constructed a platform for vehicle’s controllability and stability study conveniently and efficiently. Based on the dynamic model of the two-mass vibration system of vehicle body and wheel, the paper builds a vibration platform using the graphical programming software LabVIEW. It establishes a sinusoidal input road surface model, simulates the sinusoidal road surface under different amplitude and frequencies, and makes it the excitation source of the vibration system. It also obtains the curves of the amplitude-frequency characteristic of vehicle body and wheel displacement on the pavement displacement, and the time-domain response and amplitude-frequency characteristic curve of the body acceleration, suspension spring dynamic deflection and wheel relative dynamic load. This simulation platform provides an intuitive and effective method for vehicle ride comfort both in time domain and frequency domain.

This paper issues the D-S evidence theory and modifies the fusion rule according to the relation of time and the NH3 content in water. A few concepts of D-S evidence theory and D-S evidence combination rule are presented. The modified D-S algorithm is simulated in time and space fusion of multi-sensor measurement system information. It could distinguish the main factor that changing the NH3 content in water. The measurement system cost could be decreased.

Motor vehicle’s controllability and stability were its fundamental performances, of which the steady state circular test (i.e. SSC) was most important, and become the basis of motor vehicle’s dynamics stability control. In this paper, two group of typical SSC data of one motor vehicle were employed and processed by the graphical programming language LabVIEW software, then the curves (Ri/Ro)-ay, (1-2)- ay and - ay were obtained. According to the curve analysis and related rules and regulations, the lateral acceleration of neutral steering an, understeering gradient U, and the vehicle body rolling rigidity K were resolved, so we could get the motor vehicle’s SSC performance comprehensive evaluation value. The work in the paper constructed a platform for vehicle’s controllability and stability study conveniently and efficiently.

With the increase in rail inspection technology, the whole rail profile can be measured by rail inspection cars or some typical static measurement instruments. Based on a large number of practical rail profile measurements, a whole rail profile auto-matching method is put forward to enhance the efficiency and accuracy of data analysis. An analytical tool applying this method is developed at the same time and the principle and calculation method of the tool will be introduced. Apart from this, data collected from in-situ measurements taken on line 2 of the Shanghai Metro will be performed and analyzed to verify this method. The main contributions of this paper are the generalization of an efficient analytical tool for the calculation of wear parameters at both specific and non-specific points and the practical application for comparison of data collected by both dynamic and static inspection with the standard, which proves that the method is correct and effective.

In order to solve the impact of environment on reasonable production capacity of large mine, analyzed the main factors of environmental pollution affecting the coal mines, illustrated the coordination and interaction of various subsystems of the industry ecosystem in chart and used the environmental quality assessment to determine the mine environment grading and partition, determine the reasonable capacity of the large mines within the bearing capacity of the environment, present environmental protection measures in different areas.

Because the traditional campus GIS (CGIS) lacks close contact and unified management between the spatial data and attribute data, it can not meet the needs of information construction and management for campus. The author proposes the system construction goals of the “digital campus”, which bases on information and figures technology, after analyzing CGIS model, functions and features.VB6.0 is the developing tool and MapX the components of MapInfo is the developing platform. The campus information’s stratification method of spatial database, the table structure of attribute database and functions of system are designed by the author. And the functions of data input, output and update; display and maintenance maps; query the shortest path are all studied. They are all the useful exploration for establishing the CGIS.

The nanoindentation of diamond crystal [100] surface is studied in this paper, by using molecular dynamics simulation method and Tersoff potential. The total number of atoms in the model is exceed to 2,000,000. The crystal structure changes and the bond formations of C atoms under pressure load are analyzed. A light load causes lattice distortion but cannot cause bond breaking or hybridization transition from sp3 to sp2. When the load is enough heavy, the energy be imposed on the workpiece will beyond the range of lattice distortion, which can cause bond break and hybridization transition from sp3 to sp2.

Maximal frequent itemsets are one of several condensed representations of frequent itemsets, which store most of the information contained in frequent itemsets using less space, thus being more suitable for stream mining. This paper focuses on mining maximal frequent itemsets approximately over a stream landmark model. A false negative method is proposed based on Chernoff Bound to save the computing and memory cost. Our experimental results on a real world dataset show that our algorithm is effective and efficient.

In order to solve the problem of load sharing in planetary gear train, the design of planetary gear train was described briefly in this paper. The calculation model of type NGW planetary gear train was established. By analyzing the variety of factors, such as selection of bearing clearance, gear modification, using of flexible structure and the sun gear floating design technology, several ways to improve the load sharing of the planetary gear train techniques were obtained, and they were verified by experiments finally.

Influences of Rashba spin-orbit interaction(SOI) effects on the ground state energy of the electron in quantum ring at zero fields are studied by means of the perturbation method. Numerical calculations for CdF2 ring are performed and the results show that the Rashba SOI makes the ground state energy of electron split into two branches, which are induced by the spin-up state and spin-down state, respectively. Two branches splitting energy increases oscillatorily with increasing the inner radius of quantum ring and decreases oscillatorily with increasing the outer radius of quantum ring. The largest Rashba spin splitting energies in the process of oscillation-increase and oscillation-decrease are 11.91meV and 13.97meV, respectively. These data and results are helpful to design and develop spin field effect transistor, spin light-emitting diode, spin resonant tunneling device, etc.

The freeboard, which is an important region in COREX melter gasifier, has drawn more and more attentions, and as a key parameter for COREX melter gasifier operation, the temperature in freeboard must be within a certain range. In this paper, the temperature field of freeboard is simulated with computational fluid dynamics(CFD). The results show that the temperature in bottom is lower than that in upper. The temperature when oxygen nozzles are open is higher than that when oxygen nozzles are off, and the temperature under different operation conditions is all about 1000 °C.

The important pyrimidine intermediate 2-chloro-4,6-diamino-5-cyanopyrimidine was prepared by the cyclization of sodium salt of 1-amino-1-cyanamino-2,2-dicyanoethylene which was obtained from sodium dicyanamide and malononitrile via the nucleophilic addition in good yield and purity. The 4,6-diamino-5-cyanopyrimidines substituted with different amino groups could be synthesized by nucleophilic substitution reaction of amines, and they have good bactericidal activities to some funguses.

The evaluations on the same factor from different experts, based on AHP, are not identical, and some even far cry, because the evaluation may be effected by the knowledge, experience and emotion of the experts. To remedy this shortage, this paper established a hierarchical analysis model based on entropy. In the model, entropy value represents the uncertainty of the results. And entropy weight reflects the contribution of every expert in the assessment. Then comprehensive combination weights of the factors are determined, reflecting the importance of every factor. Applying the method, the risk factors in some bridge construction were analyzed, and, the conclusion has important significance for correct risk countermeasures and smooth construction.

M-type hexaferrites Ba(TiMn)xFe12-2xO19 (x=0 to 2) powders were synthesized by molten salt method. X-ray diffraction, scanning electron microscope and vibrating sample magnetometer were used to analyze the structures and electromagnetic properties. The results showed that, the magnetoplumbite structures for all samples were formed. Magnetic hysteresis loop measurements of the Ba(TiMn)xFe12-2xO19, exhibitted that the saturation magnetization (Ms), the remanent magnetization (Mr) and the coercitivity (Hc) of compounds depended strongly on the chemical composition of materials. The maxium values of Ms (52.68emu/g) and Mr (32.89emu/g) of the compounds were found at x=0.5; however, the values of Hc and the areas of magnetic hysteresis loop of compounds decreased with increasing the value of x. The Ba(TiMn)1.5Fe9O19/paraffin wax composites containing 40vol% of doped barium ferrite exhibitted good absorption performances in the frequency range of 2–14 GHz.

In this paper, a new method of improving uniformity of surface roughness through controlling feed rate was proposed. A CNC grinding software based on feed rate controlling and error compensation for aspheric surface was developed. The structure and function of the software system was described. An experimental test for grinding aspheric surface of WC mould was conducted for evaluating the performance of the compensation process by using this developed software. After compensation grinding for several times, form accuracy of PV 126 nm, roughness of Ra 3.4 nm can be obtained.

M-type hexaferrites Ba(ZnZr)xFe12-2xO19 (x=0, 0.5, 1.0, 1.5) powders, have been synthesized by molten salt method, where x varies from 0 to 1.5 in steps of 0.5. X-ray diffraction (XRD), field emission scanning electron microscope (FESEM) and vibrating sample magnetometer(VSM) were used to analyze the structures and magnetic properties. The results showed that, the magnetoplumbite structures for all samples calcining at 1100°C have been formed. The magnetic hysteresis loop measurements of the hexagonal ferrites powders showed that the saturation magnetization (Ms), the remanent magnetization (Mr), and the coercitivity (Hc) of ferrites depend strongly on the chemical compositions of materials. The data showed that the max Hc was obtained when substitution of x=1.0 (Hc=63.9 Oe), while the best Ms was obtained when substitution of x=0.5 (Ms=54.02 emu/g). Zn and Zr substitutions greatly modified the magnetic properties of BaM hexaferrite.

The Co2Z hexaferrites powders, Ba3Co2Fe24O41, were synthesized by the molten salt method. The results indicated that the ferrite powders possess hexagonal shape and are well separated from one another. The composite with 40vol% Co2Z content has shown a minimum reflection loss of -24dB at 9.5GHz with a -20dB bandwidth over the extended frequency range from 8.3 to 10.2GHz in a quite thin sample with a thickness of 3.0mm. The molten salt method could be a potential way to enhance the properties of the composites filled with hexagonal ferrite powders for electromagnetic applications.

Zirconia suspensions with coarse particles were prepared and the rheogical behavior and sediment stability of such suspensions with different dispersants were studied. It was found that ZrO2 suspension stabilized with TAC (tri-ammonium citrate) has an obvious shear-thinning behavior and rapid settlement; In contrast, the suspension stabilized with arabic gum shows a shear-thickening behavior and hardly any settlement. Considering both fluidity and settlement stability, APA (ammonium-polyacrylate) was chosen as the dispersant to increase the solid volume fraction of ZrO2 suspension. Utilizing the above suspension, a kind of refractory nozzle for precision casting of a Cu-Cr alloy was prepared by gelcasting. Such nozzle has a very good resistance to thermal shock and flux scouring.

The effects of solid volume fraction (SVF) on the gelation of alumina suspensions for gelcasting, debonding and sintering of the green body were studied. It was found that with SVF rising, the gelation of alumina suspension delayed; and the strength of green body decreased. On the other hand, high SVF resulted in that polymerized acrylamide split at a relative low temperature. These phenomena manifest that the fast polymerization of monomers in high SVF alumina suspension was inhibited, and the flexibility of the gelcasting was improved. However, Excessive solid volume fraction was prone to a bad rheological behavior of alumina suspension, and deteriorated the microstructure and properties of sintered body.

A reliable reference is the key to characterize surface topography. Gaussian filtering is strongly recommended by experts in the international standardization field. However, it can be affected by abnormal surface features. Based on the principle of M-estimation, a novel robust weighting function is proposed to improve the Gaussian filtering and a 3D robust Gaussian filtering model is developed. Experimental results have proven them effective.

Various polycrystalline silicon thin films were deposited on Al2O3 ceramic substrates by RTCVD processing under different deposition conditions. The influence of deposition conditions on thin film quality was studied and a set of typical processing parameters were obtained, which would direct the RTCVD processing of thin film silicon solar cell technique.

The microwave properties of (Ca1-xBax)[(Li1/3Nb2/3)0.95Zr0.15]O3+δ(0.0≤x≤0.2, CBLNZ) ceramics were investigated. A single phase with orthorhombic perovskite structure was obtained at x = 0.0 − 0.025. Both the εr and Qf value firstly increased with increasing Ba2+ content, and then began to decrease at x = 0.025. The τf value increased from −9.4 ppm/°C at x=0.0 to 18ppm/°C at x=0.2, which could be explained by the decrease of B-site bond valence in perovskite structure.

MgAlON ceramics were prepared by spark plasma sintering (SPS) and hot pressing (HP), respectively. It was found that SPSed MgAlON samples had a single MgAlON phase with almost no open pore while HPed MgAlON had a minor AlN phase. The strength of SPSed samples is higher than 500MP, being much higher than that of the HPed samples. The experimental results revealed that that SPS was a rapid and reliable process for the further development of MgAlON.

Polycrystalline silicon layers were grown on AlN ceramic substrates in a rapid thermal chemical vapor deposition system at high temperature (~1150°C). Larger columnar grains, > 5µm in size, were obtained by the zone melting recrystallization (ZMR) technique. The p-n junction is formed by a phosphorous diffusion process to make a solar cell. Solar cell devices based on this Si layer result possess an open-circuit voltage of about 0.17V and a short-circuit current of about 6.6mA/cm2.

The thin-film of silicon deposited by RTCVD on pressureless sintered SiC substrate with the size of 30mm×20mm, which is cleaned by ultrasonic method and chemical treatment. The crystal size of silicon columnar grain can reach 190 µm and its preferred orientation is [111] after ZMR process.