¡¡
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Title
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Author
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Abstract
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| Grey
Verhulst Model of Development Cost for Torpedo |
LIANG
Qing-wei, SONG Bao-wei, JIA Yue |
Development
cost for torpedo has been paid broad attention as one of the
important parts of life cycle cost of torpedo. Using Verhulst model
of the grey system theory sets up a development cost model of
torpedo Result indicates that this model can achieve satisfactory
precision. At the same time, it has practical value. |
| Research
on Dynamical Modeling of Automobile AC Laminated Evaporator |
YANG
Chen, HE Zu-wei, HUANG Lan-qing, CHAI Hong-yang |
A
dynamical model of an automobile laminated evaporator based on
drift-flux two phase model has been formulated. Special attention is
given to the study of modeling the possible operating status of
refrigerant in the evaporator. The results show that the model is
general and flexible. The development of the model lays a reliable
foundation for the performances simulation and optimization analysis
of whole automobile air conditioning system. |
| DVD
Focus Servo System Modeling and Simulation |
WU
Gang, FAN Yuan-chun, ZHOU Quan, JIN Hui-yu |
DVD
servo system requires high precision and rapid response. Building
simulation model of DVD servo system helps to test control algorithm
before realization, and to compare different control schemes in
design DVD servo system. The focus servo is the foundation of DVD
system. The model of voice coil motor and optical pickup unit are
analyzed, the model parameters are tested, the model of DVD focus
servo system is built and the simulation is carried out. |
| Modeling
and Simulation of Celestial Background |
MIAO
Yong-wei, WANG Zhang-ye, WANG Chang-bo, LIU Shi-guang, PENG
Qun-sheng |
Based
on the catalogue data, it is presented an approach for modeling and
simulating the celestial background observed in any time and at any
places. All this can be done with the Hipparcos catalogue in the
following way. First, with a series of time conversion, the star
position data of the catalogue epoch is converted into the position
data of the named time. Then, the star visional coordinate is
converted into the observation coordinate, and the star visional
position is achieved in accordance with the observe at the named
time. Finally, the celestial background at various observing time
and places can be rendered using the modeling result. |
Inter-Hierarchy
Modeling Methodology for
System-of-systems Combat Simulation
|
YANG
Feng, LI Qun, WANG Wei-ping, ZHU Yi-fan |
After
analyzing the problems facing the system-of-systems combat
simulation, including the multi-perspective problem, the
multi-resolution problem and the uncertainty problem, the authors
propose inter-hierarchy simulation modeling methodology and
corresponding reference model which includes the four activities of
construction, deconstruction, fit and aggregation. The main
contributions and future research directions of this methodology are
summarized. |
Study
on Reliability Simulation for Flight Control System
under the Influence of Wind
|
CHEN
Yun-xia, KANG Rui, SUN Yu-feng |
Reliability is
an important design index. Variable wind speed is one of the
important factors causing trajectory scatter. For the large and
complex system, it is too difficult to analyze the reliability using
the analytic methods, but the computer simulation is an effective
way. Reliability simulation for flight control system is studied in
detail by considering variable wind speed. The model of wind is
established and randomized. Influence principle of wind for flight
control system is studied, and motion equations of missile are
modified. Algorithm of reliability simulation is discussed in
detail, and formulae of computing reliability are given. Finally,
the method is verified by X-missile¡¯s flight control system. |
| Mechanism
Analysis of Genetic Algorithm Based on Distance Space |
CUI
Zhi-hua, ZENG Jian-chao, YANG Xiao-mei |
Through
mechanism analysis of simple genetic algorithm (SGA), every genetic
operator can be considered as a linear transform to the
corresponding individuals. From the point of function, it is a
desirable research aspect to give some new genetic operator using
nonlinear transform. By the expansion of Hamming distance, a new
geometry model-distance space is introduced. In this space,
mechanism analysis of crossover and mutation operators is made.
According to the analysis, some improved measure is given. The
optimization computing of some examples is made to show that the
BCNGA has better global search capacity and rapid convergence rate.
The above work establishes a completely new mathematical analytic
method of genetic operators and contributes much to perfection and
development of the theory of genetic algorithm. |
| Modeling
Direct Methanol Fuel Cell (DMFC) Based on Improved RBF Neural
Networks Identification |
MIAO
Qing, CAO Guang-yi, ZHU Xin-jian |
For the inner
complexity of Direct Methanol Fuel cell (DMFC), mathematical
modeling of DMFC is very difficult. We try to establish the voltage
and current dynamic model of DMFC by using an improved RBF neural
networks identification technique. The concentration and flow rate
of Methanol are taken as the input and the voltage and current
response as the output of the neural networks model. 1000 groups of
experimental data are used, and the structure and an improved RBF
algorithm of neural networks identification system are described.
The validity and accuracy of modeling are tested by simulations, and
the simulation results of the comparison between RBF neural networks
and BP neural networks identification are given. The simulation
tests demonstrate that the modeling method is feasible, and that the
training of RBF networks is much faster than BP networks. The RBF
neural networks identification model established above makes it
possible to design on-line controller of DMFC. |
| Detection
of Outliers from Spacecraft Tracking Data using GP-RBF Network |
XUE
Yu-zhen, ZHANG Yu-lin, YUAN Jian-ping |
The
data, accounting for a small proportion of the measured data, which
deviate from the tendency showed by the measured data as a whole are
called outliers. Outlier detection is significant to improving
accuracy of target-tracking data. A new method based on a radial
basis function neural network with general parameter (GP-RBF) is
proposed for detecting outliers. The GP-RBF neural network can do
on-line outlier detection by adjusting the general parameter
adaptively. Simulation results show that this new method can resolve
the problem of outlier detection efficiently and quickly. |
| Object-Oriented
Simulation Method and Its Application |
SHENG
Sai-bin, WANG Bin-ru |
Different
from the traditional Simulation method, Object-Oriented Simulation (OOS)
is an application of the Object-Oriented method, an important
orientation of the modern simulation technology. It has been put
into use in many domains. An application in laboratory distributed
control system of the OOS based on OODB is introduced, using a
computer and a distributed control system to simulate the specified
industry control system. In this real-time simulation system, the
computer is used to simulate the objects under control, the
distributed control system is treated as the actual control system,
they are connected with one another by some signal conversion
boards. |
| A
Fuzzy Adaptive Tracking Algorithm Based on Current Statistical Model |
HU
Hong-tao, JING Zhong-liang, TIAN Hong-wei, HU Shi-qiang |
Current
statistical model needs to pre-define the value of maximum
accelerations of maneuvering targets. So it may be difficult to meet
all maneuvering conditions. The Fuzzy inference combined with
Current statistical model is proposed to cope with this problem.
Given the error and change of error in the last prediction, fuzzy
system on-line determines the magnitude of maximum acceleration to
adapt to different target maneuvers. Furthermore, in tracking
problem many measurement equations are non-linear. Unscented Kalman
filter is applied instead of extended Kalman filter. The Monte Carlo
simulation results show that this method outperforms the
conventional tracking algorithm based on current statistical model
in both tracking accuracy and convergence rate. |
| Real-time
Performance Modelling of Token-Passing based on RFieldbus |
OU
Wei-yan, FEI Min-rui, WANG Min, CHEN Bo-shi |
The
Token-Passing protocol in the RFieldbus (Radio-Fieldbus which
comprise two heterogeneous transmission media: wireless- and
wired-segment) system acts as a multi-server-multi-queue system. A
multi-server-single-queue RF-P model was built after the analyzing
of the dynamic boundary of Token-visiting time of Token-Passing
protocol in RFieldbus. In this model, the polling-time on the slaves
was transformed into an internal token walking time when TTR is
large enough, and the rest two queues were transformed into two
M/G/1/¡Þ systems with two different Poisson-arrival rates, so that
the complexities of the time properties in RFieldbus can be depicted
easily by 7 different parameters. With the help of
Pseudo-Conversation-Law and the K-limited scheduling an equation to
evaluate the average waiting time in RF-P model was derived. The
experiment results show that the error of this equation is round
10-20% when system load is lower than 60%. |
| Fusion
Tracking for Maneuvering Targets with Wavelet Transform Using
Bearings-Only Measurements of Two platforms |
TIAN
Hong-wei, JING Zhong-liang, HU Shi-qiang, LI Jian-xun |
Bearings-only
tracking usually faces two difficulties, nonlinear filtering and
high-rate measurements processing. It is presented a novel fusion
tracking algorithm based on wavelet transform for tracking
maneuvering target using bearings-only measurements of two
platforms. In the algorithm, Passive location method was first used
to determine the coordinates in Cartesian coordinate system, and
then interacting multiple model (IMM) algorithm based on multi-rate
kinematic model was used to estimate the state of targets. The new
algorithm can avoid nonlinear filtering and has less computational
amount. Monte Carlo simulations show the efficiency of the new
algorithm. |
The
Constant Modulus Algorithm and Subspace Approach for
Blind Fractionally Spaced Equalization
|
WANG
Yong-chuan, CHEN Zi-li, LIU Zeng-tian |
The constant
modulus algorithm (CMA) and subspace approach are both blind
algorithms, which are applied in the communication signal processing
widely. We combine the CMA with the subspace approach and propose
the CM_SUB blind equalization algorithm. Simulation results show
that the proposed CM_SUB algorithm is superior to the traditional
CMA algorithm on convergence rate. |
| The
Comparative Study of Performance of Three Types of Chaos Immune
Optimization Combination Algorithms |
GUO
Zi-long, WANG Sun-an |
On the basis
of the ergodicity and internal randomicity of the chaos iteration,
three types of novel Chaos Immune Optimization Combinational
Algorithms (CIOCA) were presented to solve the problem of poor
convergence of the Immune Evolutionary Algorithm (IEA). All the
three algorithms combined the advantage of spatial search of both
IEA and Chaos Optimization Algorithm (COA). In these three
algorithms, chaos variable was respectively loaded in the variable
group of global colony, inheritance colony and memory colony of
immune algorithm, and then a tiny disturbance was added to these
colonies and the disturbance amplitude was adjusted step by step by
virtue of the property of chaos searching. The performances of the
three algorithms were compared and the experimental results showed
that the first algorithm takes advantage in convergence property and
searching efficiency. |
| The
Modeling for Job-Shop on Maxim and Minimum Algebra |
CHEN
Jin, LIU Shu-hong, SONG Guang-lei, WANG Bin-bin |
A new algebra
model with (max,+) algebra mothed as foundation has been developed
to solve the modeling and simulation problems of parallel
multi-production line of the Job-Shop. According to the technologic
route rules and process condition rule between machine tools and
workpieces, a technology route matrix and a process order matrix are
led into to control the recurrence course of state vector of
equipment - workpieces, so, the recurrence of state vector equation
is established; The multiplication and addition rule of (max,+)
algebra are redefined to satisfy two above-mentioned rules, and
definition of zero element is formulated, so the recurrence formula
of the state matrix of linear matrix form is deduced; Act on through
a computational example the function of the process order matrix and
the advantages of the algorithm are demonstrated. This model and
method can be the new platform in DEDS field and Job-Shop
description and optimum scheduling. |
| An
Incremental Algorithm of Attribute Reduction Based on Rough Logic |
LI
Yin-hua, ZHANG Ji-fu1, GAO Su-fang |
Knowledge
reduction and the extraction of decision rules are very important in
the rough set theory. Based on rough logic, theorems is presented,
whether attribute reduction and minimal decision algorithm change or
not when a new instance is added to the universe. Based on above, an
incremental algorithm of attribute reduction is presented, which
reduces effectively calculation of seeking attribute reduction and
minimal decision algorithm, and improves the efficiency. |
| Study
on Mathematical Model for Foil-Assisted Catamaran Simulator |
REN
Jun-sheng, YANG Yan-sheng, LIU Xiu-wen |
For
the purpose of developing the shiphandling simulator for high-speed
boat, the nonlinear mathematical model is proposed for a kind of
foil-assisted catamaran. The calculations are detailed on the
relevant parameters, and the influences of environmental waves on
boat¡¯s motions are considered. Based on such a boat
¡°HC200B-A1¡±, simulation researches are carried out by use of
Matlab¡¯s Simulink Toolbox with 6 groups of wave parameters. It¡¯s
found that the amplitudes of heave and pitch motion in following
seas are larger than those in ahead seas, which agrees well with
nautical practice. And the analysis for this phenomenon is presented
from the angle of the mathematical model. Furthermore, the results
also demonstrate that the established model herein is reliable for
the high-speed boat simulator. |
| Multimodal
Functions Parallel Optimization Algorithm Based on Immune Mechanism |
LUO
Yin-sheng, LI Ren-hou, ZHANG Wei-xi |
Extremum
problem of multimodal functions is a difficult issue in optimization
fields. It is difficult for traditional search methods and simple
genetic algorithm (SGA) to find out multi-local maximum
simultaneously. A parallel optimization algorithm is proposed based
on the idea of affinity maturation of immune cells in the germinal
centers in order to achieve as many as possible local optimal
solutions. The main steps of the algorithm include hyper-mutation,
selection, memory and similarity suppression. The algorithm has been
tested to optimize different multimodal functions, and the
simulation results show that the algorithm is valid compared with
other algorithms. |
| Research
of Searching Strategy in Web Topic Crawler |
ZHANG
Ling, LIN Ya-Ping, CHEN Zhi-Ping, TONG Tiao-Sheng |
With
the rapid growth of World-Wide Web, the topic-specific crawler must
seek out pages relevant to pre-defined topics in more and more web
pages. The major problem in crawling is to perform appropriate
credit assignment to different linkages. There are two kinds of
method usually used in evaluating linkages¡¯ credit. One is based
upon the linkage¡¯s immediate reward, and another is based upon the
linkage¡¯s future reward. However in different situations, they
have respective limitation. A new crawling strategy is proposed,
which combines these two rewards to evaluate linkages together.
Moreover, we utilize the changes of rewards to speculate about how
relevant the candidate page-set is to topics, based on which the
crawler can dynamically adjust the relationship between these two
rewards. Our experiments show that compared with some traditional
algorithms, this algorithm has better performance. |
| Research
and Realization on Model Base Management System for Collaborative
Simulation |
LIU
Ke-yan, ZENG Qing-liang, XIONG Guang-leng, FAN Wen-hui |
According
to the requirement of model management in collaborative simulation,
it is investigated a 3-tiered architecture for model base based on
CORBA. An improved object-oriented model representation is proposed
using the combination of model dictionary and model structure. Model
management techniques such as model version, configuration,
manipulation are studied and realized. At last, an application
example in vehicle attitude control is provided, and the validity of
the methods above is proved. |
| Simulation
Software for Intelligent Modeling of the Hot Strip Cooling Process
on the Runout Table |
TAN
Ming-hao, PIAN Jin-xiang, CHAI Tian-you |
A
software package based on the intelligent modeling method is
developed for modeling the hot strip cooling process, which is
difficult to describe with accurate mathematical models because of
its complex nature(e.g., highly nonlinear and time varying). The
software structure and functions of the simulation package are
discussed. The simulation software is easy to use and provides a
good basis for the process modeling reearch. |
| Design
of Surgery Navigation Model Demonstration System¡¯s and Analysis of
Key Techniques |
YANG
Yi-lu, XU Xin-he |
A
set of surgery navigation system¡¯s simulation experiment or
demonstrating system is introduced. It is called as Model
Demonstration System and it is designed and developed by ourselves.
The system can be used as an experiment platform to researching
correlative algorithm or only for demonstration. It can show and
trace the 3-D position of the model and surgery tools in real time.
Its algorithm is simple and useful. The key technques of surgery
navigation system are included in this Model Demonstration System.
Hardware and software system designing are introduced as well. And
the key techniques (for example 3D localizer, coordinates
conversion, registration algorithm) of the system are explained in
detail. |
Web
Based Coupled Energy Domains Simulation Platform of MEMS:
A Bond Graph Approach
|
LIU
Yang£¬JIANG
Ping-yu |
A
Bond-Graph-Based methodology for the system level modeling and
simulation of MEMS in coupled-energy domains is presented. To allow
the coupled simulation of complex and heterogeneous micro
electromechanical systems, a web based simulation platform¡ª¡ªxj_Bond
was developed to support the tasks. To support MEMS ¡°Top-Down¡±
design flow and system level rapid modeling, a micro
electromechanical components template library including beams,
joints, plates masses, electrostatic gaps and etc, was also designed
and implemented in this platform on the basis of bond graph
multiport field and junction structures. Using a piezoelectric
Micro-Hydraulic Transducer (MHT) as an example, the corresponding
modeling and simulation process is demonstrated in terms of using
this platform. |
| Investigation
of Vehicle Driving Simulator by Distributed Virtual Reality
Technology |
CHEN
Ding-fang, LI Xun-xiang, LI Wen-feng, YIN Nian-dong |
We have
introduced the latest investigation on the vehicle driving simulator
by the distributed virtual reality technology. It is an integrated
software and hardware system that combines virtual and network
environments. The main research is focused on vision system, which
includes the exterior and interior scenes of vehicles. The following
technologies have been investigated: NURBS-based auto-adjustment and
generation of the road surface texture£¨including
road signs£©,
MipMapping generation by contour lines, no-aperture slice technology
of the model and its texture, and experimentation and interaction in
the simulation environment based on the physical properties of the
model. Some examples of this vehicle driving simulator system are
also given, such as when selecting vehicles, weather, time and some
kinds of road status. |
| A
New Simulation Frame of Information Fusion Based On Avionics System
|
XU
Yang, PAN Quan, ZHANG Hong-cai, CHENG Yong-mei |
Information
fusion is one of the key technologies in modern avionics systems. It
is proposed a new simulation framework of information fusion based
on avionics system, and an information fusion function model is
presented and analyzed in detail. This system adopts centralized
construction. It can perform information collection, target tracking
and recognition, situation and threat assessment, sensor management,
etc. Simulation demonstrates the feasibility of the framework. |
| Research
of Fault-Tolerance Mechanism in Distributed Simulation System |
LIU
Yun-sheng, ZHA Ya-bing, ZHANG Chuan-fu, ZHANG-tong, HUANG Ke-di |
We
studied and analyzed the fault tolerance problem in distributed
simulation system (DSS). First, a layered system model of DSS was
put forward. Then we analyzed and described the fault types of each
layer and constructed a fault-tolerance system for HLA-based DSS:
Distributed Simulation Fault-tolerance system (DSFT). The system
composes of three parts: simulation resource monitoring module, data
preservation module, and error recovery module. The relationship
between these modules and RTI was analyzed. In the end, we analyzed
the feasibility of making use of grid technology to assist the
realization of the system. |
| Performance
Testing on Time Management Algorithm in HLA/RTI |
HE
Shao-qing, WANG Huai-min, YAO Yi-ping, WEI Yin-ku, CHEN Jian-guo |
High
Level Architecture (HLA) is the standard for modeling and simulation
put forward by the American Department of Defense. Time management
is an important component of HLA. An exact and efficient time
management algorithm is an important factor that ensures the
advantage of the time management service in a RTI product. An
approach to test time management is presented and tested in some
typical compared and analyzed RTIs. It emphasizes particularly on
function and performance tests in time management service of
StarLink which is based CORBA and is accorded with IEEE1516
Standard. The result shows that time management service of StarLink
is more excellent than pRTI1516 in high speed LAN. |
Research
on Strategy to Improve Real-time Performance
of HLA-based Simulation System
|
LIANG
Yan-gang, TANG Guo-jin, WANG Feng |
HLA
has been accepted in the field of simulations and has become the
common standard of international Distributed Interactive Simulation
for its superiority in reusability and interoperability, but HLA/RTI
has shortages in real-time simulation. The time-delay performance of
several RTIs and the common methods to improve the real-time
performance of HLA-based simulation system are studied firstly. Then
a new approach is brought forward from the view of the simulation
application system developer based on the analysis of principal
influencing factors of the real-time performance of HLA-RTI, which
sets a management node to manage the synchronization of each node in
the simulation system. The approach is proved to be a simple and
efficient method to solve the problem of the shortage in HLA-based
real-time simulation system in a certain extent by experiments and
usage. |
| Research
Environment for Airplane Dynamic Virtual Prototyping |
WANG
Jiang-yun, WANG Xing-ren, LIU Gang |
The
research environment for airplane dynamic virtual prototyping
centers on dynamic characteristics of airplane, in which
multidisciplinary design optimization theory is analyzed and the
stability, operability, maneuverability, agility and antagonism of
airplane are studied. The environment is composed of distributed
database management system and three sub-environments, which are
mathematic simulation sub-environment, man-in-loop simulation
sub-environment and virtual battlefield simulation sub-environment.
The relationship among three sub-environments and the structure,
feature and function of each sub-environment are discussed. |
| Research
and Implement of Visualization Support Platform in Virtual
Prototyping |
MA
Ji-feng, PENG Xiao-yuan, DING Ying, CAI Zhi-hao |
Virtual
prototyping is a step-by-step refining and improving process based
on simulation model and is also a complex systematic engineering
that aims at efficient resource sharing and teamwork collaborative
work. The task of visualization support platform in virtual
prototyping is to build a toolkit, which can support the
collaborative design, development, simulation and evaluation of
weapon virtual prototyping. It is researched and summarized the
collaborative visualization technique and framework of the
visualization support platform in virtual prototype engineering. |
| VEADAM£ºA
Collaborative Virtual Design and Virtual Manufacture System |
CHEN
Xiao-wu1, SUI Ai-na, WANG Wei, HUANG Ying-chun, XU Nan, PAN Zhang-sheng,
LIN Hong-chang |
VEADAM
is a collaborative virtual design and virtual manufacture system:
according to the requirement of certain astronautics product, we
build a collaborative design, virtual assembly and virtual
manufacture environment to benefit the development of product with
virtual reality. Now VEADAM mainly implements virtual assembly which
includes system architecture, interface between pro/E and virtual
environment, constraint, cooperation, multimodal human computer
interaction. |
An
Efficient Surface Texture Mapping Method of Shadow Generation
for Image-based Object
|
SONG
Han-chen, WEI Ying-me, WU Ling-da |
In
virtual environment, the object shadow silhouette is same as the
perspective view at the position of light. It is proposed a shadow
generation method based on surface texture mapping, which divides
the object view impostor into grids and calculates the projective
point on terrain by ray tracing. The arithmetic performance is
analyzed, and scene realistic and real-time rendering with dynamic
light are obtained by successive experiments. |
| Modeling
and Simulation of Real-time Image Synthesis under Different Weathers
for Scene Matching |
XIAO
Liang, WU Hui-zhong, TANG Shu-chun, LIU Yang |
Most factors
affecting real time image synthesis including the change of
missile¡¯s poses, hypsography, meteorology and the characteristics
of image intensified CDD are investigated. Three key mathematical
models including geometry aberrance, eradiate aberrance and
camera¡¯s aberrance of digital scene image synthesis are
established. An overall designing framework for simulation system is
proposed. Furthermore, a powerful simulated real time image
synthesis system named by SMRT-SS oriented to Image Intensified CCD
camera is developed using the computing kernel of LOWTRAN-7. |
| A
Method of Surface Reconstruction of Outdoor Scenes from Laser
Scanning Data |
ZHANG
Ai-wu, SUN Wei-dong, LI Feng-ting |
According
to the features of laser scanning, we proposed a method of
self-adaptive surface reconstruction of outdoor scenes. We first
defined invalid data and valid data and extracted the main measured
structures. We then self-adaptively re-sampled from laser scanning
data by 3D feature extraction, inflexion detection and surface
curvature estimation. Finally, we gave a triangulation approach that
can recognize the holes and different objects automatically. The
experiments verify that the proposed method can be able to reduce
data, keep edges, and help to store and transmit laser data. |
| Research
on Generating and Managing 3D Large Terrain Model |
ZHANG
Heng, ZHANG Mao-jun, LIU Shao-hua |
It
is introduced the methods and steps for generating the large scale
terrain models under the context of virtual battlefield
environments. And the methods for transforming the geographic data
format and reading and presenting the civil feature data are
discussed as well. The experimental results show that the methods we
presented are efficient to create and manage a 3D large terrain
model. So these methods can provide the foundations for constructing
the virtual battlefield environments.
|
| Development
of Management Platform for 3D Model of Large Battlefield Environment |
ZHANG
Jin-tao, CAI Ji-hong, GAO Li¡¯e, LIU Wei-dong |
Making
modeling standard and managing three-dimensional model in a
canonical means would be helpful to develop a visual simulation
system of great battlefield environment. It is presented a
three-dimensional model management system. Firstly, the system¡¯s
applying and developing technology, function and framework are
introduced. Furthermore, the ModelStudio¡¯s function and
characteristics are recommended, which have been used in the system
to manage and develop models. In a latent means, it is introduced a
new assistant technology which can be used in developing
three-dimensional models of visual simulation. |
| Simulation
Analysis of Performance of 3D Imaging System |
ZHANG
Zong-hua, PENG Xiang |
Based
on the projection of fringe pattern and on active triangulation, it
is analyzed the performance of a 3D full-field imaging system and
the simulation analysis is presented. First, we briefly describe the
system setup and give an exact mathematical relationship between the
height of objects surface, the phase and the experimental setup
parameters. Using this relationship, the shape of objects can be
obtained precisely. Then, the influence on the measurement results
introduced by an inaccuracy in the determination of the systemic
parameters is investigated in detail. Finally, the experiments are
carried out to evaluate the measurement performance using the
simulated data. |
| Flight
Navigation in Virtual Space Based-on Convergent Binocular
Stereovision Model with 9 DOFs |
LI
Zi-li, XIA Xue-zhi, LIU Yu-liang1, PEN Fu-yuan, SHI Xiong |
A convergent
binocular stereovision model with 9 degree-of-freedoms (DOFs) has
been put forward and used for the transformation on imaging of
virtual scene. The formula of imaging by the left and right virtual
camera pair has been educed expressing by world coordinates of the
point in virtual scene and parameters of the convergent binocular
stereovision model with 9 DOFs. The relationship between the depth
information of the point in virtual scene and the corresponding
parallax of the virtual image pair taken by the convergent binocular
stereovision model with 9 DOFs has been expressed into a calculation
formula. The established convergent binocular stereovision model has
been used for developing an algorithm of navigation and evading
barrier for the CGF flight weapon in virtual space. |
| Dynamic
Segmentation of Hand Gesture in Hand Interaction |
GUO
Bei-yuan, FANG Wei-ning |
A
method on dynamic segmentation of hand gesture using background
image abstraction and morphological operations is discussed. Based
on the comparison between current input image and background image
abstracted by Kalman filter, new images without background are
found. Then the holes and noise of the images are filled and removed
using morphological reconstruction and close operation. Since Kalman
filter can find background automatically, this method can be used in
dynamic segmentation of hand gesture from complex background
effectively. |
An
Organization and Management Approach of Data for Real-Time
Visualization of Massive Terrain Dataset
|
DAI
Chen-guang, ZHANG Yong-sheng, DENG Xue-qing |
An
organization approach of data based on tile-pyramid model and linear
quadtree tile-index is put forward for the real-time visualization
of massive terrain dataset. The dynamic management of landscape data
is achieved with the view frustum culling technology, the
target-tile searching algorithm based on resolution-testing and the
tile-request prediction mechanism. The experiment results show that
this approach can achieve good performance for real-time rendering
of massive terrain dataset. |
| Modeling
and Simulation of Articulated Virtual Human¡¯s Arm Action |
LU
Xiao-jun, LI Yan, HE Han-gen |
During
a virtual maintenance simulation task, it¡¯s inevitable for the
articulated virtual human to manipulate all kinds of operation
objects with upper arms and hands. It is presented a virtual
human¡¯s arm action model based on Petri Nets. Firstly, joint
angles under goal state are generated from inverse kinematics
computation. Then with joint interpolation and simulation loop
iteration, all joints in joint chains are controlled. Finally the
results of simulation experiments indicate the effectiveness and
usability of the proposed method. |
| Study
on Image Jittering in Visual System of Networked Flight Simulators |
XU
Yong-bo, WANG Xing-ren, JIA Rong-zhen |
Image
jittering occurs in visual system of networked flight simulators,
when fighters watch adjacent others in formation or combat. It
destroys the feeling of reality and simulation reliability. The
causes of it, frame asynchrony and coordinate transform, will be
discussed, and then basic solutions will be investigated. The
algorithms and software implementation have been used in a certain
networked flight simulators system, with frame synchronization and
smoothing algorithm used. The application results show that the
methods can reduce image jittering efficiently. |
| Research
for Image Appraisement Base on Psycho-Physics |
LIU
Kai-long, SUN Xiang-jun, ZHAO Zhi-yong, WANG Shi-xin |
As
for the remote sensing images particular, the target is on the
critical state of found and unfound. It is not an easy task to
define with an absolute affirmation or absolute negation. The target
effect of the remote sensing images is influenced not only by the
shape and color of the target itself, but also by the factors such
as the equipment, the background similarity, the atmosphere and
climate, and the following processing. The image effect evaluation
method and computer simulation model are set up based on the
interaction of mathematical model and probability statistics, and on
the Hamming distance. The technology and thinking method can be
applied to solve the problem of image effect evaluation in other
similar systems. |
| The
Accelerating Splatting Algorithm Based on Comparability of
Adjacency-Layers |
ZHANG
Jian-xun, SUN Ji-zhou, HAN Feng-qing, ZHANG Jia-wan |
Two
adjacency-layers of volume data usually have very high
comparability. It is designed an accelerating splatting
volume-rendering algorithm based on comparability of
adjacency-layers. When the contribution of the sampling point to
screen pixels color value is computed, only the changed contribution
of the next layer sampling point changed data value to screen pixels
color value is computed. The influencing screen pixels color value
is modified based on the changed contribution value. The experiment
expresses that the new spaltting algorithm can obviously accelerate
speed of volume rendering. |
| A
High Performance Object-Oriented Scene-Graph System |
LUO
Shuo-feng, LI Xue-yao, XIONG Xin-ping, CAI Ji-hong |
This
paper describes the design and implementation of a high performance
scene-graph system. The principal design goal is to relieve 3D
graphics application developers from tedious work on low-level API
such as OpenGL and obtain maximal graphics performance. It works on
Windows and different Unix variants such as IRIX and Linux, primary
target OS being Windows and primary target hardware platform being
low-end (single processor) computer such as PC. This system is for
visual simulation, virtual reality, scientific visualization,
location-based entertainment and other 3D graphics applications. |
| Real-Time
Algorithm for Feature-based LOD Models Generation |
LI
Wei-qing, HONG Yun-xuan, WU Hui-zhong |
In
VR system, LOD models are used to accelerate the rendering of
complex scene graph. Normal LOD algorithms are based on geometry
properties. A new algorithm of LOD models automatic generation is
proposed concerning artificial features of the models. This
algorithm can generate LOD models according to not only geometry
properties but also additional features. It is easy to be
implemented and the LOD models it generates are progressive meshes
that can be rendered in real-time. The algorithm has been tested in
some applications. |
| Chaos
Synthesis via Nonlinear Tracking Control |
REN
Hai-Peng, LIU Ding |
A unified
chaos synthesis method based on tracking control is proposed for
n-dimensional continuous time affined systems. A tracking control
law is designed for a nonchaotic system to track chaotic reference
input such that the topologically conjugate chaos can be synthesized
from the controlled nonchaotic system. It is shown that this unified
method can synthesize chaos from a linear controllable system and a
nonlinear system with relative degree greater than three. |
A
Synchronization Acquisition Algorithm Using Pilot Symbols
for OFDM in HF Communications
|
KAN
Chun-rong, WANG Ting-chang |
Traditional
algorithms of OFDM signal detection and synchronization acquisition
usually can¡¯t work under low SNR. In allusion to the character of
HF channel, a synchronization acquisition scheme is proposed for
troublesome HF channels. Based on joint time and frequency offset
estimation, a reliable signal detection scheme is obtained by
modulated pilot symbols using an m-sequence. The pilot symbols are
also used for frequency and time offset acquisition. Theoretic
analysis and simulations show that this scheme works well at low SNR
in HF communications. |
| Present
Situation and Future Development of Mobile Robot Path Planning
Technology |
ZHANG
Han-dong, ZHENG Rui, CEN Yu-wan |
Mobile
robot path planning technology is one of the important domains in
mobile robot technologies¡¯ research. It includes two parts: one is
global path planning based on model that the environment of the
robot is certain and the other is local path planning based on
sensor that the environment of the robot is uncertain. Present
situation of mobile robot is summarized. In addition, the advantages
and disadvantages of these algorithms are pointed out. At last, the
trend of mobile robot path planning is described. |
| Fuzzy
Ramp Control in Freeway and Simulation Research |
LIANG
Xin-rong, LIU Zhi-yong, MAO Zong-yuan |
A
fuzzy logic approach was proposed to regulate the number of vehicles
entering a freeway entrance point during rush traffic times. The
basic structure of a fuzzy logic controller was analyzed and the
fuzzy control algorithm was formulated. The membership functions
were developed and the fuzzy logic on-ramp controller was designed
based on such traffic information as the flow, speed, occupancy, and
ramp queue length. These variables were each measured by several
sensors built into the upstream, downstream, and on-ramp portion of
the freeway. Simulation research was carried out by taking full
advantage of a computer. Simulation results show that such an
approach is practical and effective. It can avoid traffic jams and
congestion on the mainline, improve the passing capability, and make
the vehicles travel more efficiently and safely.
Keywords: freeway; fuzzy control; on-ramp; simulation
|
| Speech
Conversion for Telephone Speech Recognition |
ZUO
Guo-yu, LIU Wen-ju, RUAN Xiao-gang |
A study on
speech conversion technology is addressed to improve the telephone
speech recognition performance. The speech conversion method is
implemented by simulating the influential factors in actual
telephone connections. MLLR adaptations are conducted to evaluate
the performances of the HMM recognizers, which are trained from the
clean speech and generated data respectively. The results without
adaptation report that the models trained on generated data can give
an 18.9% higher recognition rate than those on clean speech. The
adaptation results show that MLLR algorithm contributes an extra
increase of 5.8% to the recognition rate of telephone speech system.
The experiments illustrate that telephone speech recognition
performance can be effectively improved using the generated data,
and the conversion method can reduce the acoustic mismatch between
the training and test data, which is induced by the shortage of the
actual telephone speech. |
| Robust
Static Output-Feedback Fuzzy Controller Design for Uncertain Chaotic
Systems Via LMI |
LI
De-quan, XU Xian-zhen, FEI Shu-min |
The
static-output feedback control problem of a kind of T-S fuzzy
systems is studied. A kind of new static-output feedback fuzzy
controller design method of complex nonlinear chaotic systems which
can be represented by fuzzy dynamic systems is developed. The new
method considers sufficiently the interactions among the fuzzy
sub-systems. The static-output feedback controller can be obtained
by solving a set of suitable linear matrix inequalities. Uncertain
Chen¡¯s chaotic system is given as an example to demonstrate the
effectiveness and feasibility of the proposed method. |
| Multi-objective
QoS-based Multicast Routing Algorithm Based on Bayes with Decision
Graphs |
YAO
Jin-Tao, LIN Ya-Ping, KONG Yu-Yan, CHEN Zhi-Ping, TONG Diao-Sheng |
With
increasing demand for real-time multicast communication, the
communication networks must be able to provide strict and efficient
QoS guarantees. This gives rise to the need for an efficient
multicast routing algorithm that can satisfy different QoS
constraints simultaneously. Determination of such QoS-based optimal
multicast routes can be considered as an NP problem in graph theory.
General optimal methods are to combine multiple QoS parameters into
a scalar single-objective function. It is proposed a multi-Objective
QoS-based multicast routing algorithm based on Bayes with decision
graphs, which aims at optimizing multiple QoS parameters without any
preprocessing. The simulation results demonstrate that the proposed
algorithm is capable of finding a set of QoS-based near optimized,
non-dominated multicast routes quickly. |
| The
Complexity of Modern War |
ZHAO
Xiao-zhe, GUO Rui |
The
war system is one of the typical complex giant systems. The research
on it is |
