As three control points are fixed and the fourth control point varies, the planar cubic C-curve may take on a loop, a cusp, or zero to two inflection points, depending on the position of the moving point. The plane ca...
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As three control points are fixed and the fourth control point varies, the planar cubic C-curve may take on a loop, a cusp, or zero to two inflection points, depending on the position of the moving point. The plane can, therefore, be partitioned into regions labelled according to the characterization of the curve when the fourth point is in each region. This partitioned plane is called a "characterization diagram". By moving one of the control points but fixing the rest, one can induce different characterization diagrams. In this paper, we investigate the relation among all different characterization diagrams of cubic C-curves based on the singularity conditions proposed by Yang and Wang (2004). We conclude that, no matter what the C-curve type is or which control point varies, the characterization diagrams can be obtained by cutting a common 3D characterization space with a corresponding plane.
A new robust watermarking 3D mesh model algorithm is presented in this paper. We embed two different watermarks into a 3D mesh. One of the two watermarks is based on feature information and another is embedded by Niel...
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A new robust watermarking 3D mesh model algorithm is presented in this paper. We embed two different watermarks into a 3D mesh. One of the two watermarks is based on feature information and another is embedded by Nielson norm. The two watermarks do not disturb each other. Since the algorithm is blind, it does not need the original model during extraction. The algorithm is applied to many mesh models. These experiments show that the watermarking scheme not only can keep original mesh feature information but also can resist some attacks, such as affine transformation, noising and cropping.
In modern ITS, the precise recognition of vehicle information depends upon quality of images captured by camera. According to the changing of environment lighting condition, self-adaptive automatic exposure compensati...
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ISBN:
(纸本)9780784409329
In modern ITS, the precise recognition of vehicle information depends upon quality of images captured by camera. According to the changing of environment lighting condition, self-adaptive automatic exposure compensation control for camera is one of key elements to capture high quality images. This paper proposes image Projection Information Model (IPIM). We can classify images and evaluate quality of images based on IPIM joined with vehicle and background of image average luminance level. According to the classification of images and evaluation of images quality, this paper presents a method of self-adaptive automatic exposure compensation control for camera. Copyright ASCE 2007.
This paper designs and implements a virtual demonstration system for furniture. First, in order to let users virtually dispose furniture, showing the best effect of furniture in the virtual environment, we model diffe...
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ISBN:
(纸本)9780863418273
This paper designs and implements a virtual demonstration system for furniture. First, in order to let users virtually dispose furniture, showing the best effect of furniture in the virtual environment, we model different series of a company's furniture and common houses, and create panoramic pictures and transition videos with 3D Max and image processing tools, realizing walkthrough of the furnished house. Secondly, our system adopts Open Scene Graph(OSG)platform to realize virtual demonstration of the furniture. Users can add?delete and move the 3D furniture in the virtual houses. Third, the system supports furniture demonstration in a real house. Users can import the photos of their own houses, and then dispose the selected furniture on these photos, to see the whole effect of furniture in their own real houses. The experiment result shows that the system makes customers be personally on the scene and can boost up users' purchase desire.
The team design becomes increasingly important to future manufacturing industry. This paper focus on the key issues of collaborative 3D design system through Internet or Intranet in CSCW(computer Support for Cooperati...
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ISBN:
(纸本)9780863418273
The team design becomes increasingly important to future manufacturing industry. This paper focus on the key issues of collaborative 3D design system through Internet or Intranet in CSCW(computer Support for Cooperative Work). In the paper, we propose our solutions of concurrency control tactics, collaboration aware, multi-mode communications network management, synchronous real-time protection in a collaborative 3D design system. Based on Open Source Projects-Open CASCADE and Adaptive Communication Environment (ACE), we implement our collaborative 3D design system, and experiments show our system can meet the requirements of some 3D cooperative modeling design applications.
This paper presents some new virtual reality methods for house layout and furnishing to realize interactive high realistic presentation of a furnished house. Virtual houses and furniture are built from actual schedule...
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ISBN:
(纸本)9780863418273
This paper presents some new virtual reality methods for house layout and furnishing to realize interactive high realistic presentation of a furnished house. Virtual houses and furniture are built from actual schedule drawing data by 3D-modeling technology. This paper mainly proposes four ways of demonstrating virtual house on Internet, including indoor virtual tour, fix-position panorama browse, interactively indoor touring and globe view of house layout. Taking advantage of these ways, customers can navigate in the virtual house environment through Internet, observing the layout of houses from different angles and performing some interactive actions to show house style clearly.
We present a new cellular automata model for one-lane traffic flow. In this model, we consider the driver prejudgment according to the state of the leading car. We also consider that the vehicle deceleration capabilit...
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We present a new cellular automata model for one-lane traffic flow. In this model, we consider the driver prejudgment according to the state of the leading car. We also consider that the vehicle deceleration capability is finite and the braking distance of the high-speed running cars cannot be ignored, which is not considered in most models. Furthermore, comfortable driving is considered, too. Using computer simulations we obtain some basic qualitative results and the fundamental diagram of the proposed model. In comparison with the known models, we find that the fundamental diagram of the proposed model is more realistic than that of the known models.
Nowadays, remote control applications via the Internet are going to be used more and more widely with the development of powerful chips and network technology. For applications which do not need realtime communication...
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Due to long distance and terrible environment, it is difficult to maintain spacecrafts once they were launched. Traditional On-board Software Maintenance (OBSM) often fails because of broken communication and unexpect...
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ISBN:
(纸本)9780863418365
Due to long distance and terrible environment, it is difficult to maintain spacecrafts once they were launched. Traditional On-board Software Maintenance (OBSM) often fails because of broken communication and unexpected situation. This has generated a pressing need for self-adaptive, self-repairing and self-upgrading capabilities in On-Board Maintenance (OBM) applications. In this paper, we propose a fault-tolerant on-board evolutionary platform which implements relocation of hardware and software tasks in spaceborne computing systems. Tasks can either run in software space or be put into hardware task slots according to energy-efficient or real-time requirements. The allocation of hardware and software tasks will evolve in terms of current condition to meet real-time, energy-efficient or environment requirements. Sleeping tasks, redundant FPGAs and version switching control are combined together to achieve fault-tolerance in the on-board evolutionary platform. The design theories and strategies of proposed prototype are described in detail. Simulation and experiment results are discussed as well.
Based on the space spanned by {1, t, , tn-5, sint, cost, t sin t, t cos t}, (n≥5), this paper presents a new kind of uniform splines. These splines are called uniform algebraic-trigonometric splines, which share most...
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Based on the space spanned by {1, t, , tn-5, sint, cost, t sin t, t cos t}, (n≥5), this paper presents a new kind of uniform splines. These splines are called uniform algebraic-trigonometric splines, which share most of the properties as those of the B-splines in the polynomial space. Such splines can encompass conical solenoids, involutes of circles and some other transcendent curves. The subdivision scheme of this new kind of curves is given, and it is verified to be convergent. The subdivision scheme is equal to a series of linear subdividing process, which followed the V.D. property and the convexity preserving property of the splines.
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