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2006 Vol. 32, No. 10

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Integrated thermal protection and control system design methodology for hypersonic vehicles
Wang Jun, Wang Peiguang
2006, 32(10): 1129-1134.
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To solve the problem of heat barrier which a hypersonic vehicle would encounter during its mission,the idea that thermal protection system design should be integrated with thermal control system design was described. It was concluded that the airframe structure design should be coupled with design of thermal protection system, thermal control system and propulsion system. It was regarded as an effective solution to heat barrier problem. Considerations of thermal protection and control concepts for hypersonic vehicles which had different missions were put forward. Properties of some thermal protection materials were introduced and principles to select thermal protection materials in a design were addressed. Optimization of integrated thermal protection and thermal control system was discussed. Key technologies concerning the integrated design methodology were put forward. An example was put forth to illustrate the essential approach of the integrated design methodology.
Quality data model in product lifecycle
Tang Xiaoqing, Hu Yun, Wang Xuecong
2006, 32(10): 1135-1140.
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A multi-layered quality data model framework was proposed to support product lifecycle based on the analysis of quality data throughout product lifecycle and product evolution process and action chain. The model was comprised of 6 layers, the core of which was the general bill of material(GBOM) layer made up of product structure models and product evolution models. Under the constraint of product structure, GBOM was mapped into several bill of material(BOM) views throughout a product′s lifecycle. According to the process of quality management for product lifecycle, each BOM view was then instantiated as carriers of quality data. At each stage, the quality operation activities that link quality data objects were organized around the carriers, the center of the management process. Mapped successively among carrier layer, quality process layer, quality activity layer, quality object layer and physical data layer, quality data were integrated throughout a product′s lifecycle.
Integral inference method for missile hit accuracy
Fu Huimin
2006, 32(10): 1141-1145.
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An integral inference method for missile hit accuracy is presented. Combining the simulation results of missile hit accuracy and the miss distance experiment data, the method can totally infer the miss distance experiment data of missile in various launching conditions. Furthermore, it can establish the mean, the variance and the hit probability estimators, and give their confidence limits and intervals in each launching condition. Compared with traditional methods, this method not only has higher precision, but also solves the problem of missile fire accuracy, dispersion and hit probability assessment with only one miss distance experiment datum in a launching condition.
Biomimetic mechanics of micro-air vehicles ——the aerodynamic force of butterfly in forward flight
Sun Mao, Huang Hua
2006, 32(10): 1146-1151.
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The aerodynamics force generation of a butterfly (Morpho peleides) in forward flight was studied, using the method of numerically solving the Navier-Stokes equations in moving overset grids. The results shows that the vertical and thrust forces of the wings, which balances the weight and the body drag, are mainly contributed by the drag of the wings. During the downstroke, a strong ‘vortex ring’, consistes of the leading edge vortex, the wing tip vortices and thestarting vortex, was generated. The ‘vortex ring’ containes a jet parallel to the wing flapping direction, and the jet produces a large instantaneous drag. The vertical force is mainly due to the drag of the downstroke. The thrust force is mainly due to the drag of the wings in the upstroke.
New theoretical model for drumlike silencer
Sun Xiaofeng, Wang Xiaoyu
2006, 32(10): 1152-1156.
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A new technique called drumlike silencer was used to reduce sound propagations in ducts. However, the corresponding theoretical model is only valid for a plane wave in ducts without flow. A general model for describing the effect of the drumlike silencer in ducts based on generalized Lighthill equation and Green′s function theory was put forward. Compared to the existing work, the present model includes the effect of flow Mach number, higher order modes and duct structure parameters on the sound propagation. The relevant numerical results show that the control of higher order modes in a flow duct will be much more difficult than that of plane waves. Therefore, how to carefully make use of drumlike silencer to suppress the sound propagation with more complicated noise sources is worthy to be further investigated. It is also believed the present model may play some role in the optimum design of drumlike silencer. Besides, the cavity size and the parameter of the drumlike silencer are very impossible to obtain a width bank in low frequency.
Control of tail fin flaping of robofish
Wang Tianmiao, Ma Wenkai, Liang Jianhong
2006, 32(10): 1157-1162.
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Flipping control of the tail fin with two degrees is a problem of motion control in the condition of high speed and heavy load.It demands that there be little distortion of transformation of speed and position synchronously. The sameness between propulsion by tail fin flipping and that by undulation of fish body was verified, and a math model used for flipping control was deduced according to the rule of tail fin flipping. Based on the SPC-III robot fish, in terms of the control of the main joint, the algorithm, which computes the rotational speed according to its angle position and adds compensative speed via combining the relation of its position and the time variable, was put forward. In terms of the control of the assistant joint, the following algorithm, which computes the assistant joint′s target position according to the relation of the two joints′ position and the cycle period of the program, was put forward. The achievement of high-frequency flipping was discussed. During the experimentation, the following performance of tail fin flipping was validated.
Control of attitude of the space interceptor based decision tree
Quan Quan, Cai Kaiyuan
2006, 32(10): 1163-1167.
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The idea of control based decision tree was proposed for attitude control of the space interceptor with the on-off actuators. Control decision was made every time by searching the decision tree for the path of minimum cost .The idea is quite similar to that of playing chess. The proposed pruning stragey reduced computational complexity of the decision tree. The simulation results suggest that the control based decision tree is intelligent and different pruning strategies bring different results. The simulation results also suggest that this method preferably solves the multiple input multiple output (MIMO) control problem of nonlinear and coupling system which subjects to restricted control input. This method also reduces the switch count and the consumed fuel of the engine under the precondition of meeting the control accuracy.
Stretch-bending formability of profile
Zhou Xianbin, Diao Keshan, Li Xiaoxin, Jin Chaohai
2006, 32(10): 1168-1173.
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Stretch-wrap bending is the essential forming processing for profile. Cross section distortion is the common defect during the stretch-wrap bending of profile, and it brings cross-effect with thinning of thickness and springback. The stretch-wrap bending formability for profile is much more difficult to analyze and to evaluate than that for sheet forming. The concept of stretch-wrap bending formability for profile was presented and an analytic model for profile with rectangular section was established. The effect of the geometric parameters such as section configuration, relative height and wall-thickness distribution of profile on stretch-wrap bending formability was studied based on finit element method(FEM) numerical simulation. The principle for optimization design of cross section was proposed in order to improve the stretch-wrap bending formability of profile.
Experiment of damping characteristic of non-rotating shrouded blade
Hong Jie, Shi Yajie, Liu Shuguo, Zhu Zigen
2006, 32(10): 1174-1179.
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A measurement system was designed to accurately measure dynamic responses of non-rotating shrouded blade, in which initial normal load can be put on the friction interface by a load disc accurately. The design principle of this system, the loading scheme and the test errors were described. The dynamic response of the first bending mode of the shrouded blade with different shroud contact angles and shroud places were measured under various initial normal loads on the interface and different exciting force. The effects of the initial normal load, shroud contact angle and shroud place on the friction damping were analyzed from the test data. The results indicate that there is an optimal preload under which the shroud contact can provides maximal performance in dissipating vibratory energy for a given exciting force; and the relative displacement between the interfaces larger, the dissipating vibratory energy more. The design of shroud contact angle and place should obey this rule.
Key technologies of Maglev launch assist for space launch
Liu Yu, Yang Wenjiang, Duan Yi, Chen Xiaodong
2006, 32(10): 1180-1185.
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Key technologies in Maglev launch assist for space launch were studied, such as magnetic levitation (Maglev), linear motor acceleration, aerodynamic effect and space vehicle separating technology. By the comparison of several Maglev systems, high temperature superconductor (HTS) electrodynamic suspension (EDS) system was viewed as a suited one for Maglev launch assist. Based on the static and dynamic experiments of a HTS unit, the levitation and guidance force, rigidity and damping characteristics of the HTS Maglev system were indicated. Then a demo Maglev launch assist test vehicle was built to estimate its levitation performance. By analyzing the advantage and disadvantage of two kinds of linear motor, the double-side inductive linear motor was considered a suited one, and the pulsed MHD generator was the feasible power supply system for the linear motor acceleration. Aerodynamic effect on the Maglev vehicle was studied, and the aerodynamic shape and layout were designed optimally. The basic aerodynamics characteristics were concluded, and the aerodynamic aerofoil was useful for balancing the pitching moment of the Maglev vehicle. The technology of space vehicle separating simultaneously from the direction guideway on the Maglev vehicle was studied. Based on the D' Alan Bert theory, the primary kinetic parameters of space vehicle slipping successfully away from the Maglev vehicle were obtained.
Description of hardening characteristics of sand and its confirmation
Yao Yangping, Zhou Annan, Hou Wei
2006, 32(10): 1186-1192.
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According to the test data of sand with different stress paths in the triaxial compression and triaxial extension condition, plastic volumetric strain, plastic shear strain, hardening parameter of Tsinghua model, plastic work and unified hardening parameter H were chosen as hardening parameter respectively, and then the hardening rules as well as the independence on the stress paths of above hardening parameters were discussed. Based on the yield function of modified cam-clay model, constitutive models which used plastic volumetric strain, plastic work and unified hardening parameter H respectively as hardening parameter were proposed. The validity of unified hardening parameter H on describing the stress-strain properties of sands was confirmed by the triaxial test data of saturated sand from Taklamakan desert.
Plating metal film on the surface of particles using magnetron sputtering method
Shen Zhigang, Yu Xiaozheng, Xu Zheng, Pei Xihua
2006, 32(10): 1193-1198.
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The metal copper and nickel film was deposited on particles by direct current magnetron sputtering method under different working conditions. The surface morphology, film thickness, chemical composition, film grain size as well as the film crystallization of particles were analyzed by optical microscope (OM), field emission scanning electron microscopy (FESEM), energy dispersive spectroscopy (EDS), multimode scanning probe microscope (SPM),inductively coupled plasma-atom emission spectrometer (ICP-AES), X-ray photoelectron spectroscopic (XPS) and X-ray diffraction (XRD) respectively before and after the plating process. The effects of different sputtering conditions on crystallization of metal films deposited on particles were discussed. The results indicate that the relatively uniform, compact and adhesive metal films were successfully deposited on particles through controlling the motion mode of particles during the sputter deposition. With the increasing of sputtering time or the increasing of sputtering power or the decreasing of the particle loading amount, both crystallization and grain size of metal film were improved.
Point-line-surface conceptual model for information systems with applications
Xiong Zhang, Pu Juhua, Lu Xiaofeng, Xue Ling
2006, 32(10): 1199-1204.
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Workflow technology, which plays a more and more important role in enterprise information systems, mainly concerns the translation of business models into processes that can be understood and automatically dealt with by computer systems. A prerequisite for applying workflow technology is to effectively analyze enterprise business. As a result, how to analyze and model enterprise business is a fundamental problem in enterprise information systems design. There isn′t yet any universal approach to performing this critical task, and it′s usually done in an ad hoc way. On this ground, the point-line-surface(PLS) conceptual model as a universal approach was proposed to analyze enterprise business. The entities PLS includes were defined and the mapping betweenPLS entities and EPC entities was illustrated. The enforcement of PLS model and its EPC description are demonstrated by our experience in the construction management information system for south-to-north water diversion middle route project.
Integrated flexible reliability and fault diagnosis design technique
Zhao Tingdi, Tian Jin
2006, 32(10): 1205-1208.
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In order to meet the demand that modern satellite be high-reliability and long-life, flexible restructuring was executed among the components insides atellite or among the satellites in a mission group, by means of grid and multi-disciplinary technology, based on characteristics of digitalized system or equipment of satellite and over-all properties of system. Thus system reliability ofsatellite or satellite group could be increased. A technique that integrates flexible reliability design, testing and fault diagnosis/recovery processing was put forward, and design & analysis to reliability, testability and fault diagnosis/recovery was combined with design to function/performance of products. The corresponding integrated design & analysis model was established, and simulation for application was carried on. Therefore, the digitalized system or equipment of satellite could be ensured simple-structured, low-cost and reliable.
Algorithm of multi-objective prediction on logistics volume of combined transportation
Xu Xiangyang, Wang Shuhan, Tang Pengxiang, Shi Gan
2006, 32(10): 1209-1214.
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A new method was brought forward for the modeling of multi-objective prediction on logistics volume of combined transportation. Based on the standard of time, field, influence and combined transportation, using systems engineering antilogy, a model of four-dimensional factors of logistics volume was designedand optimized by using structural equation model. The fatal influencing factors of logistics volume of combined transportation were distilled. A new advanced neural network arithmetic integrated with genetic algorithm was put forward to make up the limitation of advanced neural network, and applied in a example of multi-objective prediction on logistics volume of combined transportation. Results show that this advanced algorithm performs steadily with high precision and convergence speed.
Upper bounds of efficiency loss for user equilibrium behavior in traffic networks
Huang Haijun, Ouyang Lianqun, Liu Tianliang
2006, 32(10): 1215-1219.
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Determining the upper bounds of efficiency loss for user equilibrium behavior in traffic networks has become a hot topic. The relationship between user equilibrium and system optimum flow patterns was explored in traffic networks with fixed demands. New formulae for computing the upper bounds of efficiency loss caused by user equilibrium behavior were derived through introducing a parameter associated with the user equilibrium flow pattern. Numerical examples show that the new formulae can give lower values of the upper bounds than those reported in literature. It is also concluded that finding more accurate upper bounds has to be connected with all characteristics of the studied networks, including the link cost functions, the network configurations and the travel demands.
Option games model of firm′s investment strategy in oligopoly
Qiu Wanhua, Yu Dongping
2006, 32(10): 1220-1225.
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The firm′s investment strategy was examined in oligopoly and the firm′s optimal equilibrium exercise strategy of real options was analyzed systemicallyunder incomplete competition. The research shows that there are three equilibriums, such as preemption, sequence and simultaneous investment, when existing negative externalities, However, there is just simultaneous investment equilibrium, when positive externalities. The firm′s value and optimal investment threshold increase with the raise of market uncertainty. Competitive interaction accelerates investment, furthermore the threshold is between monopolistic investment threshold and Marshallian investment tlhreshold, even though the firm number is infinite.
Design of semantics-oriented C4ISR/Sim integrated system
Tan Juan, Li Bohu
2006, 32(10): 1226-1230.
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C4ISR(command control communications computers intelligence surveillance and reconnaissance)/Sim(simulation) integrated system developed under service-oriented architecture(SOA) can use same information acquiring methods and information representation syntax. Semantics-oriented C4ISR/Sim integrated system proposed is to extend SOA by hierarchical semantic structure, which was improved in flexibility, reusability and expansibility of system construction as well as semantic interoperability of integrated system. Based on domain ontological model in core service layer, the architecture expanded semantic description of model service in domain-specific service layer. Using semantic service matching, it realized automatic mapping between requiring description in application layer and the composition of system. Realization of prototype system proves that its design method is correct and applicable.
Multi-view point clouds registration method based on planar target
Sun Junhua, Zhang Guangjun, Wei Zhenzhong
2006, 32(10): 1231-1234.
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Multi-view point clouds registration is one of the key techniques in 3D vision measurement for large object. A planar target with some corners as feature points was designed. The distances between those feature points were accurately known. The target was placed at the common region which was measured by a vision sensor at two different view-points, and the vision sensor measured the 3D coordinates of the feature points twice. By establishing unit orthogonal basis using 3 arbitrary non-colinear points on the target, the original coordinate frame transformation matrix for multi-view point clouds was found. An objective function for the sum of distances′ squares between the correspondent feature points was established after original registration, and the distances control was introduced to increase constraint. The optimal results were finally estimated by Levenberg-Marquardt optimization algorithm taking original coordinate frame transformation matrix as the initial value. A plaster model was measured by a binocular vision sensor at two positions. The experimental results show that the proposed registration method is simple and reliable, and the registration accuracy after optimizing is improved by about 31%.
Numerical simulation on upstream dual rods′ effect on aerodynamic characteristics of cylinder
Zhang Panfeng, Wang Jinjun, Wu Zhe
2006, 32(10): 1235-1240.
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Numerical simulation was constructed to investigate the upstream dual rods′ effect on the characteristics of the cylinder at Reynolds number 200. The unsteady laminar model was solved by SIMPLE method with CFD(computational fluid dynamics) commercial software package FLUENT 6.0. When the dual rods have small vertical interval (H/d=1.1, 1.33), there is only one Karman vortex street formed behind the rods. This case is much more similar to that of a single rod, but the critical spacing ratio for the flow pattern transition is larger than that of the single one. That means there are two different flow patterns with the spacing ratio increase, the cavity flow mode and the wake impinging mode. In the cavity flow mode, the maximum drag and RMS (root mean square) value of lift were reduced by 94% and 79%, respectively. The system drag (including the rod and the cylinder drag) was reduced by 33%. If there are two vortex streets behind the rods with large vertical interval (H/d=3.33, 5.0), the upwind surface of the cylinder is also impinged by the gap flow between the rods, which results in the drag and RMS value of lift reduction is limited.
EMC pre-design technologies on EW special aircraft
Su Donglin, Wang Bingqie, Jin Dekun, Ouyang Shaoxiu
2006, 32(10): 1241-1245.
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To resolve the disadvantages of the traditional electromagnetic compatibility (EMC) design method on electronic warfare (EW) special aircraft, a novel method named "top-down, systemic, quantificational pre-design" was presented and applied. As design scheme of EW special aircraft was conceived, systemic energy-transmission models and interfered relationship matrices were devised. Then the security of on-vehicle receivers, fuze, fuel, aviators and operators was analyzed with the method of numerical simulation, behavioral level simulation, equivalent calculation, statistics of datum, etc. The perfect system EMC performance can be achieved by evaluating EMC performance, distributing the EMC parameters quantificationally, optimizing design time after time. In addition, the system EMC performance can be analyzed along with the change of subsystem parameters. The subsystem parameters can be adjusted to meet the system EMC performance as well. The potential EMC problems can be exposed at the stage of design and resolved before the design was finalized. It has been applied in EMC design on a number of special aircrafts with a high success rate, and offered important technical support for resolving the acute EMC problems in research and development of models.
One lightweight internet protocol over fibre channel
Xu Yajun, Zhang Xiaolin, Guo Caijian, Xiong Huagang
2006, 32(10): 1246-1249.
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One upper level protocol of fibre channel (FC) should be properly adopted for FC physical network testing. Internet protocol (IP) over FC is one important upper level protocol of FC and is very mature. Based on IP over FC, one new lightweight internet protocol ( LIP) over FC was proposed. Transmission mode and data format of LIP over FC was defined. Based on device driver program of IP over FC, the communication of LIP over FC was implemented by embedding intermediate driver in Microsoft 2000 operating system. FC analysis instrument can be used to take stock of the implement result. Data format of result is accord with design. Using LIP over FC, the communication efficiency of short messages can be enormously improved. Transmission mode of LIP over FC is very simple and flexible, identifier of FC nodes is easy to achieved. So LIP over FC is adapt to test physical network capability of FC.
Multidisciplinary design optimization of gas-generator body
Tong Xiaoyan, Cai Guobiao, Chen Jun, Wang Jue
2006, 32(10): 1250-1254.
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To exploit a generic multidisciplinary design optimization (MDO) method on liquid propellant rocket engines, a gas-generator body in a liquid propellant rocket engine was used as the object of this research. Based on the design-oriented multidisciplinary analysis, the multidisciplinary design optimization model of the gas-generator body was constructed. Three coupling disciplines, fluiddynamics, heat transfer and mechanics were included in the MDO model. A new multi-objective method called physical programming was introduced to deal with the multi-objective optimization problem in this research. In physical programming, the objective in the optimization problem reflects the preference of designers through class function, which avoids the balance among objectives with different magnitudes and dimensions. The result shows that the mass of the gas generator was reduced and the original design was improved by multidisciplinary design optimization. Multidisciplinary design optimization can be used to obtain the better design of the whole liquid propellant rocket engines.
Corrosion resistance characteristic of continuous basalt fiber and its reinforcing composites
Wang Mingchao, Zhang Zuoguang, Sun Zhijie, Li Min
2006, 32(10): 1255-1258.
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To explore the corrosion property of a new kind basalt fiber and its reinforcing composites, the basalt fiber was boiled 3h in water, sodium hydroxide and hydrochloric acid. The residual tensile strength and mass loss of basalt fiber after boiled were investigated. It was showed that the alkali resistance of the basalt fiber is better than acid resistance. To investigate the chemical durability of basalt composite in different mediums, samples were immersed in eight kinds of chemical mediums for 15, 30 and 90 days. After each period of immersion, the bending properties were tested and surface morphologies were observed. Study results reveal that the corrosion behavior of composite is very different in acid and alkaline due to the basalt fiber resistance difference. In acid mediums, the bending strength and bending module change in the same way. In alkaline mediums, bending module is very blunt compared with bending strength, bending module keeps close to the originality while bending strength declines gradually.
Vacancy formation energy of intermetallic with L10 structure
Shu Xiaolin, Chen Ziyu, Chen Qiang, Hu Wangyu
2006, 32(10): 1259-1262.
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Equiatomic CoPt and FePt alloy films with the L10-ordered structure have been attractive as ultrahigh-density magnetic recording media. The vacancy formation energies of some intermetallics with L10-ordered structure were calculated by Miedema′s theory. The types of structural vacancy in the intermetallics were discussed. The Ni vacancy is easy formed in FeNi. The type of structural vacancy in FePt and FePd is the Fe vacancy. The Co vacancy is easy formed in CoPt. The Ni vacancy is easy formed in NiPt. The Pt vacancy is easy formed in MnPt. The type of structural vacancy in MnNi is the Ni vacancy. The Mn vacancy is easy formed in MnPd and MnHg. The Rh vacancy is easy formed in MnRh. This research is provided the reference in researching ultrahigh-density magnetic recording films.

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