A variable-bit-rate characteristic waveform interpolation （VBR-CWI） speech codec with about 1.8 kbit/s average bit rate which integrates phonetic classification into characteristic waveform （CW） decomposition is p...A variable-bit-rate characteristic waveform interpolation （VBR-CWI） speech codec with about 1.8 kbit/s average bit rate which integrates phonetic classification into characteristic waveform （CW） decomposition is proposed. Each input frame is classified into one of 4 phonetic classes. Non-speech frames are represented with Bark-band noise model. The extracted CWs become rapidly evolving waveforms （REWs） or slowly evolving waveforms （SEWs） in the cases of unvoiced or stationary voiced frames respectively, while mixed voiced frames use the same CW decomposition as that in the conventional CWI. Experimental results show that the proposed codec can eliminate most buzzy and noisy artifacts existing in the fixed-bit-rate characteristic waveform interpolation （FBR-CWI） speech codec, the average bit rate can be much lower, and its reconstructed speech quality is much better than FS 1 016 CELP at 4.8 kbit/s and similar to G. 723.1 ACELP at 5.3 kbit/s.展开更多
For a very long time video processing dealt exclusively with fixed-rate sequences of rectangular shaped images. However, interest has been recently moving toward a more flexible concept in which the subject of the pro...For a very long time video processing dealt exclusively with fixed-rate sequences of rectangular shaped images. However, interest has been recently moving toward a more flexible concept in which the subject of the processing and encoding operations is a set of visual elements organized in both time and space in a flexible and arbitrarily complex way. The moving picture experts group (MPEG- 4) standard supports this concept and its verification model (VM) encoder has adopted scalable rate control (SRC) as the rate control scheme, which is based on the spatial domain and compatible with constant bit rate (CBR) and variable bit rate (VBR). In this paper,a new rate control algorithm based on the DCT domain instead of the pixel domain is presented. More-(over), macroblock level rate control scheme to compute the quantization step for each macroblock has been adopted. The experimental results show that the new algorithm can achieve a much better result than the original one in both peak signal-to-noise ratio (PSNR) and the coding bits, and that the new algorithm is more flexible than test model 5 (TM5) rate control algorithm.展开更多
近年来,超宽带(Ultra-wideband,UWB)通信技术因其具有数据传输速率高、功耗低、保密性高、成本低等诸多优点,成为室内高速数据传输的一种有效解决方案。由于高速通信下码间串扰极大地影响了UWB系统的接收性能,需要在解调前采用Rake接收...近年来,超宽带(Ultra-wideband,UWB)通信技术因其具有数据传输速率高、功耗低、保密性高、成本低等诸多优点,成为室内高速数据传输的一种有效解决方案。由于高速通信下码间串扰极大地影响了UWB系统的接收性能,需要在解调前采用Rake接收机和均衡等手段消除码间串扰。针对自适应最小误码率(Adaptive Minimum Bit Error Rate,AMBER)均衡算法与Rake接收机结合进行研究,提出了一种变步长自适应最小误码率(Variable Step-Adaptive Minimum Bit Error Rate,VS-AMBER)均衡算法,在较低信噪比和较高信噪比情况下分别使用不同的变步长方案,较高信噪比下在收敛速度和收敛精度上有所提升,较低信噪比下降低了误码率和功耗。展开更多
In Mobile Ad-hoc Networks (MANETs), routing protocols directly affect various indices of network Quality of Service (QoS), so they play an important role in network performance. To address the drawbacks associated wit...In Mobile Ad-hoc Networks (MANETs), routing protocols directly affect various indices of network Quality of Service (QoS), so they play an important role in network performance. To address the drawbacks associated with traditional routing protocols in MANETs, such as poor anti-fading performance and slow convergence rate, for basic Dynamic Source Routing (DSR), we propose a new routing model based on Grover's searching algorithm. With this new routing model, each node maintains a node vector function, and all the nodes can obtain a node probability vector using Grover's algorithm, and then select an optimal routing according to node probability. Simulation results show that compared with DSR, this new routing protocol can effectively extend the network lifetime, as well as reduce the network delay and the number of routing hops. It can also significantly improve the anti-jamming capability of the network.展开更多
A new variable bit rate layered coding scheme based on subband coding is given in this paper. It can make full use of the merits of ATM transmission, as well as compensation for the quality degradation caused by cell ...A new variable bit rate layered coding scheme based on subband coding is given in this paper. It can make full use of the merits of ATM transmission, as well as compensation for the quality degradation caused by cell loss, which is an inherent problem of ATM networks, and thus a stable, high quality video transmission is achieved. This paper presents the coding scheme, cell construction and simulation results.展开更多
Transmission of variable bit rate (VBR) video, because of the burstiness of VBR video traffic, has high fluctuation in bandwidth requirement. Traffic smoothing algorithm is very efficient in reducing burstiness of the...Transmission of variable bit rate (VBR) video, because of the burstiness of VBR video traffic, has high fluctuation in bandwidth requirement. Traffic smoothing algorithm is very efficient in reducing burstiness of the VBR video stream by trans- mitting data in a series of fixed rates. We propose in this paper a novel segment-based bandwidth allocation algorithm which dynamically adjusts the segmentation boundary and changes the transmission rate at the latest possible point so that the video segment will be extended as long as possible and the number of rate changes can be as small as possible while keeping the peak rate low. Simulation results showed that our approach has small bandwidth requirement, high bandwidth utilization and low computation cost.展开更多
This paper extends the previous experimental work on Planck’s constant h and the vacuum field, whose spectrum is determined by h. In particular it adds additional experimental evidence supporting temporal and spatial...This paper extends the previous experimental work on Planck’s constant h and the vacuum field, whose spectrum is determined by h. In particular it adds additional experimental evidence supporting temporal and spatial variations in the vacuum field, including the Sun as a source at 13 sigmas of certainty. The vacuum field has long been a mystery of physics, having enormous theoretical intensity set by Planck’s constant h and yet no obvious physical effect. Hendrick Casimir first proposed that this form of E & M radiation was real in 1948 and suggested an experiment to verify its existence. Over 50 experiments since then have confirmed that this vacuum radiation is real, is a form of electro-magnetic radiation, and varies in time and space over 10:1 in our laboratory compared to its standard QM spectrum. Two other authors have found the fine structure constant α (proportional to 1/h) is varying across the cosmos at up to 4.2 sigma certainty. All these results suggest that the vacuum field (and thus h) varies in time and space. In a previous paper we reported our tunnel diode experimental results as well as the results of six other organizations (including German, Russian and US national labs).The six organizations reported sinusoidal annual variations of 1000 - 3000 ppm (peak-to-valley) in the decay rates of 8 radionuclides over a 20-year span, including beta decay (weak interaction) and alpha decay (strong interaction). All decay rates peaked in January-February and minimized in July-August without any candidate cause suggested. We confirmed that Planck’s constant was the cause by verifying similar variations in Esaki tunnel diode current, which is purely electromagnetic. The combined data from previous strong and weak decays plus our own E & M tunnel data showed similar magnitude and time phasing for strong, weak and E & M interactions, except that the tunnel diode temporal variations were 180 deg out of phase—as we predicted. The logic for this 180 deg phase shift was straight forward. Radioactive decay and electron tunneling both have h in the denominator of the tunneling exponent, but tunnel diodes also have h2 in the numerator of the exponent due to the size of atoms being proportional to h2. This extra h2 makes the exponent proportional to h for electron tunneling instead of proportional to 1/h for strong and weak decay—shifting the annual oscillation for E & M tunnel current by 180 deg. Radioactive decay had a maximum around January-February of each year and a minimum around July-August of each year. Tunnel current (the equivalent to radioactive decay rate) had the opposite—a minimum around January of each year and a maximum around July of each year. This predicted and observed sign flip in the temporal variations between radioactive decay and electron tunneling provides strong evidence that h variations across the Earth’s orbit are the cause of these annual cycles. In this paper we take the next step by verifying whether the Sun and a potential more distant cosmic source radiate the vacuum E & M field, just as all stars generate massive amounts of regular E & M radiation. We reprocessed two years of data, 6 million data points, from our tunnel diode experiment to search for day-night oscillations in tunnel current. Here we assume that the Earth would block the radiated vacuum field half of each day. Sun-locked signals have 365 cycles per year and cosmos locked signals have 366 cycles per year. With our two years of data, these two signals are separated by a null-signal, which is not locked to the Earth or to the cosmos—allowing us to clearly distinguish the solar and cosmic sources. 1) We found sun-locked variations in the vacuum field, peaking around local noon with 10-13 probability of false alarm. Other potential causes are carefully examined and ruled out. 2) We also found cosmos-locked variations in the vacuum field, peaking at the right ascension of the red super-giant star Betelgeuse with 10-7 probability of false alarm. Cosmos locked sources are easily distinguished from the solar source because they have one extra cycle per year, two extra cycles during the two years of the experiment. They are thus independent Fourier components, easily separated by a Fourier transform. Both of these high probability detections support that the vacuum field spectrum may vary in space and time and be enhanced by stellar sources.展开更多
A comprehensive research on key issues of the large-scale video server system for Video On Demand (VOD) client/server system is conducted based mainly on real time (rt)/non-real time (nrt) Variable Bit Rate or Constan...A comprehensive research on key issues of the large-scale video server system for Video On Demand (VOD) client/server system is conducted based mainly on real time (rt)/non-real time (nrt) Variable Bit Rate or Constant Bit Rate (VBR/CBR) MPEG-2 MP@ML Signal Program Transport Stream (SPTS) for movies, and general architecture for storage, control, caching subsystems from Loosely Coupled Computer (LCC), Symmetric Multiple Processing (SMP), and Massively Parallel Processing (MPP) video server is conceptualized. Meanwhile, Redundant Array of Inexpensive Disks (RAID) storage system are presented and the centralized FCP/SAN huge storage technology is introduced in terms of its scalability, throughput, and connectivity performances.展开更多
文摘A variable-bit-rate characteristic waveform interpolation （VBR-CWI） speech codec with about 1.8 kbit/s average bit rate which integrates phonetic classification into characteristic waveform （CW） decomposition is proposed. Each input frame is classified into one of 4 phonetic classes. Non-speech frames are represented with Bark-band noise model. The extracted CWs become rapidly evolving waveforms （REWs） or slowly evolving waveforms （SEWs） in the cases of unvoiced or stationary voiced frames respectively, while mixed voiced frames use the same CW decomposition as that in the conventional CWI. Experimental results show that the proposed codec can eliminate most buzzy and noisy artifacts existing in the fixed-bit-rate characteristic waveform interpolation （FBR-CWI） speech codec, the average bit rate can be much lower, and its reconstructed speech quality is much better than FS 1 016 CELP at 4.8 kbit/s and similar to G. 723.1 ACELP at 5.3 kbit/s.
文摘For a very long time video processing dealt exclusively with fixed-rate sequences of rectangular shaped images. However, interest has been recently moving toward a more flexible concept in which the subject of the processing and encoding operations is a set of visual elements organized in both time and space in a flexible and arbitrarily complex way. The moving picture experts group (MPEG- 4) standard supports this concept and its verification model (VM) encoder has adopted scalable rate control (SRC) as the rate control scheme, which is based on the spatial domain and compatible with constant bit rate (CBR) and variable bit rate (VBR). In this paper,a new rate control algorithm based on the DCT domain instead of the pixel domain is presented. More-(over), macroblock level rate control scheme to compute the quantization step for each macroblock has been adopted. The experimental results show that the new algorithm can achieve a much better result than the original one in both peak signal-to-noise ratio (PSNR) and the coding bits, and that the new algorithm is more flexible than test model 5 (TM5) rate control algorithm.
文摘近年来,超宽带(Ultra-wideband,UWB)通信技术因其具有数据传输速率高、功耗低、保密性高、成本低等诸多优点,成为室内高速数据传输的一种有效解决方案。由于高速通信下码间串扰极大地影响了UWB系统的接收性能,需要在解调前采用Rake接收机和均衡等手段消除码间串扰。针对自适应最小误码率(Adaptive Minimum Bit Error Rate,AMBER)均衡算法与Rake接收机结合进行研究,提出了一种变步长自适应最小误码率(Variable Step-Adaptive Minimum Bit Error Rate,VS-AMBER)均衡算法,在较低信噪比和较高信噪比情况下分别使用不同的变步长方案,较高信噪比下在收敛速度和收敛精度上有所提升,较低信噪比下降低了误码率和功耗。
基金supported by Zhejiang Provincial Key Laboratory of Communication Networks and Applications and National Natural Science Foundation of China under Grant No.60872020
文摘In Mobile Ad-hoc Networks (MANETs), routing protocols directly affect various indices of network Quality of Service (QoS), so they play an important role in network performance. To address the drawbacks associated with traditional routing protocols in MANETs, such as poor anti-fading performance and slow convergence rate, for basic Dynamic Source Routing (DSR), we propose a new routing model based on Grover's searching algorithm. With this new routing model, each node maintains a node vector function, and all the nodes can obtain a node probability vector using Grover's algorithm, and then select an optimal routing according to node probability. Simulation results show that compared with DSR, this new routing protocol can effectively extend the network lifetime, as well as reduce the network delay and the number of routing hops. It can also significantly improve the anti-jamming capability of the network.
文摘A new variable bit rate layered coding scheme based on subband coding is given in this paper. It can make full use of the merits of ATM transmission, as well as compensation for the quality degradation caused by cell loss, which is an inherent problem of ATM networks, and thus a stable, high quality video transmission is achieved. This paper presents the coding scheme, cell construction and simulation results.
基金Project supported by the Hi-Tech Research and Development Pro-gram (863) of China (No. 2003AA103810) and the National NaturalScience Foundation of China (No. 60332030)
文摘Transmission of variable bit rate (VBR) video, because of the burstiness of VBR video traffic, has high fluctuation in bandwidth requirement. Traffic smoothing algorithm is very efficient in reducing burstiness of the VBR video stream by trans- mitting data in a series of fixed rates. We propose in this paper a novel segment-based bandwidth allocation algorithm which dynamically adjusts the segmentation boundary and changes the transmission rate at the latest possible point so that the video segment will be extended as long as possible and the number of rate changes can be as small as possible while keeping the peak rate low. Simulation results showed that our approach has small bandwidth requirement, high bandwidth utilization and low computation cost.
文摘This paper extends the previous experimental work on Planck’s constant h and the vacuum field, whose spectrum is determined by h. In particular it adds additional experimental evidence supporting temporal and spatial variations in the vacuum field, including the Sun as a source at 13 sigmas of certainty. The vacuum field has long been a mystery of physics, having enormous theoretical intensity set by Planck’s constant h and yet no obvious physical effect. Hendrick Casimir first proposed that this form of E & M radiation was real in 1948 and suggested an experiment to verify its existence. Over 50 experiments since then have confirmed that this vacuum radiation is real, is a form of electro-magnetic radiation, and varies in time and space over 10:1 in our laboratory compared to its standard QM spectrum. Two other authors have found the fine structure constant α (proportional to 1/h) is varying across the cosmos at up to 4.2 sigma certainty. All these results suggest that the vacuum field (and thus h) varies in time and space. In a previous paper we reported our tunnel diode experimental results as well as the results of six other organizations (including German, Russian and US national labs).The six organizations reported sinusoidal annual variations of 1000 - 3000 ppm (peak-to-valley) in the decay rates of 8 radionuclides over a 20-year span, including beta decay (weak interaction) and alpha decay (strong interaction). All decay rates peaked in January-February and minimized in July-August without any candidate cause suggested. We confirmed that Planck’s constant was the cause by verifying similar variations in Esaki tunnel diode current, which is purely electromagnetic. The combined data from previous strong and weak decays plus our own E & M tunnel data showed similar magnitude and time phasing for strong, weak and E & M interactions, except that the tunnel diode temporal variations were 180 deg out of phase—as we predicted. The logic for this 180 deg phase shift was straight forward. Radioactive decay and electron tunneling both have h in the denominator of the tunneling exponent, but tunnel diodes also have h2 in the numerator of the exponent due to the size of atoms being proportional to h2. This extra h2 makes the exponent proportional to h for electron tunneling instead of proportional to 1/h for strong and weak decay—shifting the annual oscillation for E & M tunnel current by 180 deg. Radioactive decay had a maximum around January-February of each year and a minimum around July-August of each year. Tunnel current (the equivalent to radioactive decay rate) had the opposite—a minimum around January of each year and a maximum around July of each year. This predicted and observed sign flip in the temporal variations between radioactive decay and electron tunneling provides strong evidence that h variations across the Earth’s orbit are the cause of these annual cycles. In this paper we take the next step by verifying whether the Sun and a potential more distant cosmic source radiate the vacuum E & M field, just as all stars generate massive amounts of regular E & M radiation. We reprocessed two years of data, 6 million data points, from our tunnel diode experiment to search for day-night oscillations in tunnel current. Here we assume that the Earth would block the radiated vacuum field half of each day. Sun-locked signals have 365 cycles per year and cosmos locked signals have 366 cycles per year. With our two years of data, these two signals are separated by a null-signal, which is not locked to the Earth or to the cosmos—allowing us to clearly distinguish the solar and cosmic sources. 1) We found sun-locked variations in the vacuum field, peaking around local noon with 10-13 probability of false alarm. Other potential causes are carefully examined and ruled out. 2) We also found cosmos-locked variations in the vacuum field, peaking at the right ascension of the red super-giant star Betelgeuse with 10-7 probability of false alarm. Cosmos locked sources are easily distinguished from the solar source because they have one extra cycle per year, two extra cycles during the two years of the experiment. They are thus independent Fourier components, easily separated by a Fourier transform. Both of these high probability detections support that the vacuum field spectrum may vary in space and time and be enhanced by stellar sources.
文摘A comprehensive research on key issues of the large-scale video server system for Video On Demand (VOD) client/server system is conducted based mainly on real time (rt)/non-real time (nrt) Variable Bit Rate or Constant Bit Rate (VBR/CBR) MPEG-2 MP@ML Signal Program Transport Stream (SPTS) for movies, and general architecture for storage, control, caching subsystems from Loosely Coupled Computer (LCC), Symmetric Multiple Processing (SMP), and Massively Parallel Processing (MPP) video server is conceptualized. Meanwhile, Redundant Array of Inexpensive Disks (RAID) storage system are presented and the centralized FCP/SAN huge storage technology is introduced in terms of its scalability, throughput, and connectivity performances.
