As the environment of space network is much different from that of terrestrial wired network, the application of TCP
protocol in space network may faces some special challenges, First is that the Round Trip Time (RTT) is greatly
increased by the long propagation on the space radio channel, Second is that the high packets error rate resulting from
space channel cannot be considered negligible, Both these aspects may result in the TCP transmitting efficiency
degradation. A new scheme to enhance the TCP transmitting efficiency is proposed in this paper, simulation results
show that both the throughput and time delay is greatly improved by the use of this scheme.
Functional Near-Infrared Spectroscopy (fNIRS) is a powerful non-invasive method to measure hemodynamic changes in
tissues, while electroencephalography (EEG) provides excellent neuronal-electrical information in functional brain
mapping. We developed an fNIRS/ERP instrument which can concurrently monitor the electrical neuronal activation and
the hemodynamic response for the study of neurovascular coupling of the human brain. The probe of the instrument
consists of 1 LED operating at three different wavelengths (735 nm & 805 nm & 850 nm) and 2 photodiodes (PDs) with
the interoptode distance up to 3 cm, and an Ag-AgCl electrode lies in the center of the LED-PD pairs. The four
components are encapsulated in a black sponge to decrease the interference of outside light as well as facilitate the
placement on the forehead. The signals from the PDs and the electrode separately pass though two adjustable
amplify-filter circuits which amplify the weak signals and block the high frequency interferences. A high speed data
acquisition board samples the modulated signals under the control of a home-made software. The time resolution of the
instrument achieves less than 10ms, which makes it realizable to compare the fNIRS data with the ERP data.
As an important branch of visual reality technology, augmented reality has been applied to vast fields like commerce and education. This paper verifies the feasibility of applying augmented reality technology to the planning of residential district. A visual district planning system is designed and realized on the basis of augmented reality. It fully reflects the advantages of augmented reality technology in the application to district planning by meeting the requirements of district planning for visual-real interaction and man-machine interaction. This paper further describes visual-real registration technique based on computer vision and adopted by the system. Moreover, the results of system operation are given.
The principle to construct G&IBMR virtual scene based on stereo panorama with binocular stereovision was put forward. Closed cubic B-splines have been used for content-based segmentation to virtual objects of stereo panorama and all objects in current viewing frustum would be ordered in current object linked list (COLL) by their depth information. The formula has been educed to calculate the depth information of a point in virtual scene by the parallax based on a parallel binocular vision model. A bilinear interpolation algorithm has been submitted to deform the segmentation template and take image splicing between three key positions. We also use the positional and directional transformation of binocular virtual camera bound to user avatar to drive the transformation of stereo panorama so as to achieve real-time consistency about perspective relationship and image masking. The experimental result has shown that the algorithm in this paper is effective and feasible.
A technical principle about construction of virtual studio has been proposed where orientation tracker and telemeter has been used for improving conventional BETACAM pickup camera and connecting with the software module of the host. A model of virtual camera named Camera & Post-camera Coupling Pair has been put forward, which is different from the common model in computer graphics and has been bound to real BETACAM pickup camera for shooting. The formula has been educed to compute the foreground frame buffer image and the background frame buffer image of the virtual scene whose boundary is based on the depth information of target point of the real BETACAM pickup camera's projective ray. The effect of real-time consistency has been achieved between the video image sequences of the master of ceremonies or players and the CG video image sequences for the virtual scene in spatial position, perspective relationship and image object masking. The experimental result has shown that the technological scheme of construction of virtual studio submitted in this paper is feasible and more applicative and more effective than the existing technology to establish a virtual studio based on color-key and image synthesis with background using non-linear video editing technique.
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