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LNG carrier is purposed to transport a liquefied LNG cargo which is reduced to 1/600 of volume in temperature condition of -163°C. In the context of structural performance on LNG cargo hold, the mechanical and thermal behaviors of insulation material under cryogenic temperature are considered as one of the critical factors for the hold design. This paper deals with the thermal deformation and the compressive strength of the reinforced polyurethane foam (RPUF) adapted for the insulation material of membrane type LNG carrier via both material tests and numerical simulations realizing the cryogenic condition. The material tests related to the thermal deformation are carried out to investigate the characteristics for thermal transfer on the actual RPUF specimen. The heat transfer simulations based on finite element analysis (FEA) are carried out using forced convection theory. The results of heat transfer analyses are compared to the material test results. Reasonable cryogenic conditions on RPUF are reviewed from both the analyses and the test results. In the regard of static material strength for the RPUF, the compressive material tests are carried out. The cryogenic temperature effect on the compressive strength of RPUF is evaluated by comparing to the room temperature material test results. From the compressive material tests, the effect of temperature on the ultimate compressive strength is investigated with variation of elongation.

Using first principles approach, we present the structural, vibrational and dielectric properties of α-SiO2. The calculations have been carried out within the density functional perturbation theory and linear response formalism using the norm-concerving pseudopotentials and a plane wave basis. All the vibrational modes identified are in good agreement with experiment. The calculated infrared spectra are also in good agreement with available experimental results both for the positions and the intensities of the main peaks. We find that the modes Eu7 and A2u4 splits in two respectively at high hydrostaticpressures. Then we calculate the infrared spectra under high pressure of different orientations. The vibrational modes in different phase transitions are reported and discussed respectively.

Due to mechanical performances of brace and steel plate, mechanical properties of semi-rigid joints and its construction and installation, semi-rigid steel frame-braced steel plate shear wall system is proposed. Nonlinear static analysis with parameters (thickness of plate, type of brace, size of brace and the ratio of span to height) changed of a single-span and single-floor semi-rigid steel frame-braced steel plate shear wall system illustrates that braced steel plate shear walls contributes obviously to bearing capacity and lateral rigidity of semi-rigid steel frame. Also, the finite element analysis (by ANSYS) show that semi-rigid steel frame-braced steel plate shear wall system has excellent ductility.

A model with the ratio of 1:4 of a six layers’ semi-rigid steel frame-steel plate shear wallssystem has been tested on the shaking table.The strain variation of the steel plate shear wallsand the system’s seismic behaviors to different kinds of seismic waves from four different siteclassification and with different peakaccelerationwere analyzed to provide theoretical and experimental evidence to the real projects.

VSC-HVDC is usually associated with the AC system, which will be inevitably affected by AC system.VSC-HVDC mostly operates in the environment of strong current and high voltage, which will lead some parts of internal device to be interfered or damaged.This paper studies the control technology of VSC-HVDC in AC system fault mode to ensure that the device itself is not only perfect but timely rescue the AC system when it is necessary.

The technology of VSC-HVDC transmission has a high degree of flexibility and controllability.This paper researches the control strategy of VSC-HVDC and the operating principle of the wind turbine, which can effectively enhance the stability of power system in the region of wind farms, improve the long-distance transmission capacity of wind power and stabilize the voltage level of public connection point.

In smart substation, transmission line longitudinal protection debugging cannot take place, before the line communication channels construction, that cause it often occur that not fully debug, choose a suitable time for debugging in advance. In this paper, based on the analysis of the longitudinal protection debugging process, combining with the computer technology, and 3G/4G communication technology, design a set of intelligent substation EHV-line longitudinal protection device of temporary channels. Ensure, in intelligent substation, carry out advanced debugging, select the appropriate time debugging, debugging completely, before the longitudinal channel built, and establish a reliable foundation for the normal operation of the longitudinal protection equipment.

The idea of enhancing the growing of tourism through information system has existed in the early years and it was also emphasized in the 12th five-year plan. After the experience of three phases of information technology development, China’s online tourism business is constantly improving with the establishment of a multifunctional online tourist industry system. However, information technology is updating and surpassing with each day when tourism is developing. The special nature of the relationship between supply and demand in tourist industry makes information exchange play a significant role in the running of the industry. Thus, the application of information technology not only exerts great impact on the transaction and relationship between supply and demand, but also makes the entire industry transform a lot. Tourist industry makes enormous progress in value transmission, message transmission and e-commerce by applying information technology that activates the industry effectively. Thus, information system is tremendously important in data analysis and assessment of tourism industry chains.

In view of the risk to use the traditional rheostat Slide Rheostat and the contradiction between its range and accuracy, in this paper, designed automatically adjust the rheostat of resistance based on the traditional rheostat, and further study on combination relationship between different range and precision resistor. The host controller and the under controller was designed too. The slide rheostat can solve the existing problems between range and resistance and operational safety, and improve the safety and adjusting speed during operation.

This paper studies control and motion theory of feed system of the five-axis CNC machine tools, propose the method of establish mathematical model, kinematics model of the feed system, in order to provide a method of theoretical research for accuracy identification of five-axis CNC machine tools.

In this paper, a solution based on the elliptic integrals is proposed for solving multiples inflection points large deflection. Application of the Bernoulli Euler equations of compliant mechanisms with large deflection equation of beam is obtained ,there is no inflection point and inflection points in two cases respectively. The elliptic integral solution which is the most accurate method at present for analyzing large deflections of cantilever beams in compliant mechanisms.

The automatic control system is one of the most important parts of improve cold rolling strip precision and increase the automate level. The improved cold strip mill process control system has been developed and successfully applied to several new cold strip production lines. This paper introduces the Key Technical Features and New Technology of the system include the system architecture, hardware configuration and new control algorithms, etc. System operation and actual production proves that the system has the features of shorter commissioning time, convenient maintenance, high reliability, high automatic level and control precision.

In this paper, the problem of the excessive generator tripping value of security and stability control after occurrence of the N-2 fault in the Shentou-Yantong transmission line of Shanxi DaTong Regional grid is studied. And the principle of security and stability control measures based on equal area criterion is analyzed. The reason leading to excessive generator-tripping value of security and stability control after the occurrence of the N-2 fault in Shentou-Yantong region is figured out, and it is that the steady-state stability limit of transmission section decreases and the accelerator power cannot be released. Finally, the results of theoretical analysis are verified by simulations. The simulation results indicate that too large generator-tripping value of security and stability control is mainly caused by decrease of the steady-state stability limit of the transmission section after occurrence of the fault in Datong. The conclusions in the paper have referential significance for the study on similar power concentrated send-out systems.

In order to improve the efficiency of people evacuation from hazardous regions and reduce the ill effects of disasters, a distributed decision support system for large scale crowd evacuation is proposed. The system is supported by the technology of Web Geographic Information System (WebGIS). Basically, by analyzing the system framework we may acquire a novel approach to establish a distributed large-scale crowd evacuation platform for emergency management. Research results show that the proposed system is useful for devising evacuation plans in advance as well as real-time management under disaster.

In order to solve the problem of high voltage system which caused by an excess of system reactive power during the systems valleyload period,this paper described the methods of leading phase operation of generator to adjust the system voltage to the reasonable range, which is proved feasible and effective through the field test.

The error sources of machining accuracy of CNC machine tools including geometric error, thermal error, system error and error of load control etc. The error source affect the relative position of the cutting tool and the workpiece by the dynamic motion, and then affect the machining accuracy of the workpiece. By trial cutting method, "S" test part is a new test part for detecting machining accuracy of five-axis linkage machine tools. Through experiment and simulation, identification of the error source of the machining accuracy and the regular of "S" test part surface errors, surface quality, results show that "S" test part can reflect the machining accuracy of CNC machine tool.

This paper analyzes CNC machine tools machining error sources, put forward a kind of on-line monitoring technology of CNC machine tools machining accuracy based on online neural network. Through the establishment of CNC machine tools condition monitoring platform, collection sensor signal of the key components of CNC machine tools, using time domain and frequency domain method of the original signal processing, extract the characteristic related to machining accuracy change, input to the neural network, identification the changes of machining accuracy. The experimental results show that, the on-line monitoring technology based on neural network, can identify the changes of machining accuracy.

According to coupling phenomenon of reactive power when a power plant is connected to another power plant, reactive power can not be to achieve a reasonable distribution of each power plant,which causes the problem of voltage control. This paper describes the methods of adjusting the parameters of automatic voltage control (AVC) to realize the coordinated control between power plants connected, which makes the voltage of power system to meet the demand of power grid operation.

Regional energy base with large installed capacity, small local power load capacity and great amount of power transmission have been more and more common in China. For this kind of sending end power grid, the 3rd line of defense for frequency stability is crucial. The high frequency generator tripping is an effective emergency frequency control measure. But its setting and configuration mainly relies on operational experience and off-line simulation calculation. An equivalent model suitable for the analysis and setting calculation of high frequency generator tripping is introduced firstly. Based on the model, and aimed at an actual frequency emergency control problem, a scheme for high frequency generator tripping is proposed. Furthermore, a speed-up tripping scheme using df/dt criterion is proposed to optimize the frequency response. Numerical simulations are conducted on real power grid model of Shanxi province to demonstrate the effectiveness and adaptability of this scheme. The setting principle and calculation method of high frequency generator tripping can introduce to similar power grid for reference.

This paper presents a detailed review of the existing methods of the optimal control of distributed generation system and the state of the art of current research. The research of the optimal control of distributed generation system is summarized in terms optimal dispatch and control strategy. The approach of modeling and analysis for distributed generation system is described in detail. The key difficulties of the theory and technique about the optimal control of distributed generation system are analyzed. The current issues about the optimal control of the system are pointed out at last, and the research orientations of the optimal control of distributed generation system are presented.

On the basis of GR log analysis alone, the high GR sandstone reservoirs would probably have been regarded as mudstone and interpreted to be non-reservoir, which has greatly affected the exploration and exploitation of oil and gas reservoir to some extent. Therefore, the principles and standards to distinguish high GR sandstone reservoir from conventional sandstone reservoir, genesis of high GR sandstone reservoir have been systematically studied. Studies show that sandstone reservoir with apparent shale content calculated by GR log value greater than 50%, can be regarded as high GR sandstone reservoir. In the study area, the specific criterion of GR log value for high GR sandstone reservoir is 110API. The high GR characteristic of sandstone reservoir is mainly and directly caused by an abnormally high uranium enrichment, but not the tuff, feldspar or clay mineral. The study area has favorable conditions of abundant uranium source, favorable paleoclimate, and favorable lithology and lithofacies combination for uranium enrichment. In the process of oxygen bearing formation water migrating and leaching uranium bearing tuff, the U+4 can be oxidized to U+6, and uranium element transports in the form of UO2+2. In permeable sandstone reservoir saturated with uranium bearing formation water, the U+6 can be deoxidized into U+4 by oil and gas migrating through faults and stratigraphic unconformities, and accumulates in the form of UO2 in sandstones.

Because of personnel deployment flow, protection equipment and electric device replacement, and enterprise scale expansion, setting management is more difficult. It is easy to be out of control and become the main reason for the anti-grade trip. To solve the anti-grade trip problem of setting mismanagement, this paper designed one setting management system, which is composed of slave controller and upper server. After analysis, the communication process based on the TCP/IP protocols, the communication scheme is chosen between slave controller and upper server. Software within upper server is designed based on database technology. Slave controller gets the setting from relay protection device, by using IEC 60870-5-103 protocols based on serial communication, and sends to the software within the upper server, which can monitor, display and record. Setting management problem was solved, which is caused by the personnel deployment flow, protection equipment replacement, and enterprise scale expansion. This method can be widely used.

The paper introduces the Multi-parameter Multi-objective Algorithm, it be used to apply a logistics management project of the China National Natural Science Foundation. This paper from the two math problems TSP and VRP talked about, and then introduces the two different algorithm and feature; the former is the ant colony algorithm in modern intelligent bionics using it to solve the TSP, latter is its improved algorithm, Multi-parameter Multi-objective Algorithm, using it to solve the VRP. The "bionic computing intelligent logistics management system" is based on this Algorithm. Later it introduces how to adopt different working process oriented, handle customer request, in the management system, the differences between the original algorithm and the evolution algorithm.

Because of time urgent before putting into operation and different place line protection equipment located, joint debugging for extra high voltage (EHV) transmission line is often not perfect although EHV transmission line is very important for modern grid. In joint debugging process, we tend to adopt static method to do fault simulation, that apply analogue to the device. To overcome the shortages of static fault simulation commonly used, which cannot accurately simulate fault characteristics in runtime, a synchronous joint debugging device is designed based on based on the analysis of the joint debugging process for line longitudinal protection. The device is a lightweight and low cost embedded system with the functions of communication and phase shift, and can offer analog signals to protection devices on both ends of the line. Based on the functions and characteristics of the synchronous joint debugging device, the joint debugging process with this device of optical fiber differential protection is analyzed. The functions of this synchronize testing device can meet the requirements, turning static to dynamic joint debugging.

Analyse the cause of fault in CNC Machine, research the corresponding solve scheme, and to realize the state can monitor equipment operation, improve equipment reliability, the development set of machine condition monitoring, fault warning, fault diagnosis and troubleshooting as one of the intelligent security system. Based on the CNC machine intelligence support system research, design, introduces the key technologies and methods. Screw lift state of motion monitoring, for example, trend analysis exercise state, intelligent fault diagnosis, in order to achieve protection of the intelligent CNC machine tools to verify the practicality of intelligent security systems.

Cubic Cu2O nanoparticles were synthesized via hydrothermal route without template. The study of different reaction conditions reveals that the concentrate of NaOH affects the size and the morphology of nanocubes.

Wheat straw alkali treatment has impacts on the strength of cement mortar and glazed hollow beads insulation mortar. The results show that the bending strength and bending strength of cement mortar specimen with 4% wheat straw are respectively 58.3% and 40.9% of the benchmark specimen, but bending-press ratio of the latter is 1.42 times of the former. The SEM images reflect the straws influences on the cement hydrate morphology, status and the influence of the number on cement mortar and glazed hollow beads insulation mortar. Compared with the latter, the former C-S-H gel is loose fibrous, failure to form a good network. In the thermal insulation mortar consistency and stratification of the same circumstances, with straw dosage increased, strength first increases, then declining. And folding pressure than in straw dosage is less than 24% more ideal. The SEM pictures show that network C-S-H gel decrease and loose fibrous C-S-H gel increased. At the same time, AFt gradually become attenuate and curly.

The objective of this study is to propose the effective method of reducing the maximum contact pressure at the contact edge of press-fitted shaft by optimizing the location and the size of stress relief groove in hub face. Finite element analysis was performed in order to determine the contact pressure and stress state on a press-fitted assembly and optimization were applied to select optimal size and location of stress relief groove. In order to reduce the cost of optimization design, approximation optimization method is used and the optimum results obtained by Sequential Quadratic Programming and genetic algorithm are compared. Optimized results show that the maximum contact pressure at the contact edge of press-fitted shaft with optimal stress relief groove decreased about 30%. And the both optimization algorithms can effectively reduced the maximum contact pressure at the contact edge of press-fitted shaft.

We reported the superlattices (SL) thin films of ferroelectric BiFeO3 and ferromagnetic La0.7Sr0.3MnO3 on structure and ferroelectric properties, which fabricate by (radio frequency)-magnetic sputtering. Remarkably, the SL thin film has orientation (100), and the interphases are very distinct. We examined samples by XRD, and Keithley 2400, and the result proves the thin film is SL, which is oriented (001), affected by strain and temperature. And strain affect growing of thin film, and temperature affect electricity property.

Based on the characteristics of the three types of data from the system of WAMS (Wide Area Measurement System), SCADA (Supervisory Control And Data Acquisition) and Fault-recorder, this paper present an algorithm to do the voltage or reactive power optimization based on the primal-dual interior point method, and a new method to filter out the noise in state variable based on the standardized residuals. The flow chart proposes a new scheme to use the WAMS real-time data to improve the accuracy of voltage and reactive power control. Keywords: WAMS, voltage and reactive power control, primal-dual interior point method, standardized residuals.

The volumetric errors modal is built with the coordinate errors of each axis of CNC machine tool through the laser interferometer. The volumetric errors in the workspace are calculated with the errors prediction modal. With the calculated results of volumetric errors, the errors tendency of CNC machine tool can be predicted. Besides, the specific accuracy testing projects can be conducted by the errors areas taken care more. The main errors of CNC machine tool will be tested rapidly and efficiently.

The main purpose of this study is to develop a numerical model to describe the static recrystallization kinetics in X70 pipeline steel. In order to investigate the static softening behavior, double-hit compression tests were performed on a Gleeble-3500 thermomechanical simulator over a temperature range of 950-1150°C. The interpass time varies from 1-500s. Different values were applied to estimate effects of strain rate and deformation on static recrystallization. The results show that factors such as high temperature, long holding time and lower strain rate will lead to the inclination of softening behavior. The static softening activation energy was obtained. The good agreement between the predicted values and experimental results indicated the validation of the developed model of this study.

In order to compensate the noise brought by piezoelectric gyroscope or external environment and track the resonance frequency, Closed Loop Driving Circuit (CLDC) of piezoelectric solid-state micro gyroscope is proposted in the paper which will stabilize the driving voltage value and keep the resonance frequency tracked. CLDC mainly contains Phase Lock Loop (PLL) circuit, Automatic Gain Circuit (AGC). Experimental results show that the fluctuation of reference voltage is within ±7mv, while the fluctuation of reference voltage in Open Loop Driving Circuit (OLDC) without noise compensation is ±23mv. The frequency of CLDC drifts within 0.03 kHz with the resonance frequency of 357.9 kHz while the OLDC can’t track any drifting.

NAS (National Aerospace Standard) 979 is the only standard well known in industry describing a five-axis machining test for measuring kinematic errors of five-axis machine tools. As it cannot reflect the tool path characteristics of typical ruled surface machining, five-axis machine tools which passed the NAS test may not have the ability to satisfy the requirement of the real industrial applications. To fill this gap between the NAS test and the real industrial applications, an “S” machining test is proposed in this paper. The case study shows that the proposed machining test is feasible and practicable.

Investigation on the heat transfer and friction characters for fresh oil flowing inside three-dimensional internally finned tube (3-DIFT) was carried out with orthogonal experimental design method. Reynolds numbers varied from 30 to 800，Prandtl numbers 550 to 1000. The experimental results showed that low critical Reynolds numbers at the range of 100 to 200 were attained within all the experimental tubes, which indicated that 3-DIFT could obvious accelerate the transformation of high viscous fluid from laminar flow to turbulent flow. It offered a particular advantage to enhance the convective heat transfer of highly viscous fluid. Empirical equations on flow resistance and heat transfer were obtained using a least-squares regression. Compared with empty smooth tube, the maximal thermal performance factor for the turbulent flow within 3-DIFT could be enhanced up to 3.61. The optimization on shape of 3-DIFT for further augmentation heat transfer was also obtained.

The author took Chuanlingdong Bridge in Fujian Province for example. Applying general FEM software ANSYS and sub modeling technique, 3D model of the whole bridge was built firstly, and then closure section and nearby sections in mid-span were built to sub model. In the sub model, initial mesh was refined, weaken effects of corrugated pipes were considered and plain bars also were built. Based on the fine sub model, original design and construction tolerances are analyzed respectively. At last spatial stresses of closure section were cleared and key influencing factors were concluded. This research showed construction tolerances had a great influence on bursting damage when the design was at a disadvantage.

Reinforcement learning algorithm for multi-robot may will become very slow when the number of robots is increasing resulting in an exponential increase of state space. A sequential Q-learning base on knowledge sharing is presented. The rule repository of robots behaviors is firstly initialized in the process of reinforcement learning. Mobile robots obtain present environmental state by sensors. Then the state will be matched to determine if the relevant behavior rule has been stored in database. If the rule is present, an action will be chosen in accordance with the knowledge and the rules, and the matching weight will be refined. Otherwise the new rule will be joined in the database. The robots learn according to a given sequence and share the behavior database. We examine the algorithm by multi-robot following-surrounding behavior, and find that the improved algorithm can effectively accelerate the convergence speed.

A fiber optic sensor system based on stimulated Brillouin scattering is realized to measure the strain distribution along the fiber itself as a sensing medium. Prototypes of the system are advanced from the partly integrated system to reinforced cooling system with fully integrated following the schematic diagram which improves the stability of the optical power with polarization maintaining fiber components. Single lock-in detection using optical chopper is used to achieve the high signal to noise ratio. Optical components are separated with optical logger to isolate the heats from electronic components such as electric power, lock-in amplifier, DAQ and lots of controllers. Electronic logger is designed with air cooling system. 3D design of optical and electronic logger is drafted.

Web Geographic Information System (WebGIS) has drawn numerous attentions from developers, and it has much effect on our lives for its combination of Internet and GIS technology. This paper presents a component based WebGIS development framework. In the proposed system, Supermap IS .Net is used as the basic platform, and ASP.NET as the web application development environment, where Ajax is considered as the method for asynchronous communication. Moreover, the technology of component is employed for the construction of an extensible framework for WebGIS applications.

In this work, 3-dimensional flower-like Y2O3:Eu3+ microstructures were synthesized through a facile route using simple hydrothermal reaction and sequentially calcinations without templates or matrix. The flower-like micro-architectures are self-assembled by nanosheets with thickness of about 50 nm and diameter about 3-5 μm, which were verified by the field-emission electron microscopy (FESEM) and transmission electron microscope (TEM). The as-synthesized Y2O3:Eu3+ samples show a strong red emission due to 5D0-7F2 transition (612nm), suggesting potential applications in red phosphors.

Based on FEM program ANSYS and the OpenGL graphics, this paper develops the parametric modeling module and the computing module of the multi-tower suspension bridge, this module being embedded into the ANSYS system, and the parametric modeling module parameters can be entered by way of interface, which establish fast a multi-tower suspension bridge model. Calculation module can establish load conditions for the features of road bridge and specifications, in which multiple conditions can be defined and solved automatically. Post-processing part of the solution also for the results of the subtotals and select the output, so that the results of the output and finishing work has become more convenient and easier, and also the results can also be saved in word, excel and other different file types.

Hierarchical porous titanate nanotube hollow microspheres were synthesized through a template-hydrothermal method. First, SiO2@TiO2 core-shell structure was synthesized, and then titanate nanotube hollow sphere was prepared via a simple hydrothermal method. The dimension of the cavity could be simply tuned by controlling the size of SiO2 spheres. These hollow microspheres exhibited a unique porous structure, in which the nanotube hollow microsphere had a two-fold storage system including the cavity of the hollow sphere and the nanotube capability. Further, the microsphere demonstrated an improved controlled releasing performance that the cavity was capable of giving a fast releasing, while the channel of the nanotube showed a slow releasing property. This facile template-hydrothermal method could be a generally strategy to prepare hollow nanostructures.

Five axis linkage CNC machine tools, with its high speed, high precision characteristics, are widely used in large aircraft structure part machining. By trial cutting method, "S" test part is a new test part for detecting processing accuracy of five-axis linkage machine tools. Through analysis and simulation, exploring the influencing factors to CNC machine tools processing accuracy and the regular of "S" test part surface errors, surface quality, results show that "S" test part can reflect the processing accuracy of CNC machine tools.

Nickel coating was prepared on surface of Epoxy Resin plate by electroless plating process. Surface and section morphologies of the coatings were observed by scanning electron microscopy (SEM) and metallographic optic microscopy. Electromagnetic shielding effectiveness was evaluated via flanged coaxial electromagnetic shielding effectiveness tester. The results showed that the surface of the nickel coating prepared by electroless plating process was smooth, and its structure was fine and compact. The electroless deposition rate of the nickel coating reached at 12μm/h. In the frequency range of 300 kHz to 100MHz the electromagnetic shielding effectiveness of the nickel coating was above 60dB, and in the frequency range of 100MHz to 1.5GHz the electromagnetic shielding effectiveness of the nickel coating was above 44dB.

Combined with numerical simulation, a radial-directional dynamic tensile experimental method was proposed based on conventional split Hopkinson tensile bar(SHTB) for a thin-walled tube structure with special ring section. A special clamp was designed and a hollow transmission bar was used to magnify the transmission signals. For the stainless steel thin-walled tube structure, some dynamic tensile experiments are implemented under different strain rates. The results show that this test method is applicable to thin-walled tube structure with special ring section. This structure has a long plastic stage and its fracture strain is reduced with strain rate increasing. Moreover, its tensile strength is obviously enhanced with strain rate increasing

The optimization theory of the motorcycle frame structure was described. The FEM model of the frame structure was established by Hyperworks software, the stress and fatigue stress of the frame structure was analyzed. The frame parts were optimized through the size and topology optimization according to the stress and the displacement. The result showed that the stress of the frame structure changed little comparing with that before, which was in the permitted range of engineering design. The cost of the motorcycle frame structure was reduced, and the frame weight was lightened about 6.5%.

The GIS technology provides a new mechanism and an effective method to develop Digital City, which is an important node of implementing the digital earth. In this paper, the framework of Digital City based on GIS is investigated. Through GIS service, the urban spatial data and attribute data can be accessed and integrated seamlessly to various Digital City applications. Moreover, a Digital City application is given to illustrate the key techniques based on MapObjects of ESRI and an objects-oriented developing tool, namely, Visual C++. Experiment results show the robustness and efficiency of the proposed method.

The mathematical simulations of the galvanic coupling intra-body communication (IBC) with different signal transmission paths have been introduced. Firstly, a galvanic coupling IBC circuit model was developed and the transfer function was derived. Secondly, the corresponding parameters were discussed. Finally, the signal attenuation characteristics of the galvanic coupling IBC were measured along the different signal transmission paths of the actual human bodies, while the corresponding mathematical simulations based on the proposed transfer function were carried out. A close agreement between the simulation results and measurement results has been demonstrated.

Particle system is an essential building block for visualize various types of special effects in applications of computer graphics. In this paper, we propose a novel approach based on particle system editor supported by GPU (Graphic Process Units) to provide a WYSIWYG (What You See Is What You Get) editing environment for simplifying special effects development process, where a SPH (Smoothed Particle Hydrodynamics) solver is used for particles movement simulation. Experimental results show the robustness and efficiency of the proposed system for computer games in real time.

Load structure method is commonly used in tunnel design; there are two problems for its implementation in Marc software: first, the force cannot be applied directly in Marc; second, the position of the spring around the tunnel is unknown. In view of first problem, by means of force conversion, a subroutine programming with Fortran is adopted to exert the force. For the second problem, iterative algorithm is adopted; the tension spring will exit calculation, and a comparison of the spring position in the two steps will be made, if the position is the same, the computation will finish. The work above realizes the Load structure method in Marc software and enlarges the application of Marc software in underground engineering. The verification example is given to prove the validity of the interface subroutine.