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A process to improve the properties of reclaimed polyethylene (RPE) polymer modified asphalt mixture by grafting of maleic anhydride (MAH) onto RPE (RPE-g-MAH) in the presence of dicumyl peroxide (DCP) as initiator was proposed. Fourier transform infrared spectra (FTIR) was employed to verify the grafting of MAH onto RPE. Modified asphalt mixture under different conditions were investigated on the RPE-g-MAH samples. To assess the effects of the RPE-g-MAH on the high-temperature stability of modified asphalt mixture, we discussed dynamic stability (DS) and rutting depth (RD) of modified asphalt mixture by studying the influences of various experimental parameters such as MAH content, DCP content, mixing temperature, wet mixing times and gradation type of mixture. Experimental results indicated that the RPE-g-MAH is feasible to improve high-temperature stability performance and low-temperature performance of asphalt mixture, and it could dramatically improve resistance to rutting of the asphalt mixture. Possible mechanism was proposed for RPE-g-MAH modification of asphalt mixture.

This paper proposes a new high-performance switching element with the new shared-memory queuing policy, which is called blocked-cell shared-memory (BCSM) queuing. As the name means, instead of buffering all cells through them, the BCSM switching elements only buffer the blocked cells at their input ports. Theoretic analysis results under the uniform traffic model prove that BCSM switching elements have better performance than shared-memory switching elements.

This paper studies two kinds of methods for pitch predictor in speech compressing coding, i.e., open-loop and closed-loop structures. Some of simplified approaches for solving pitch predictor equation are suggested, and the performances are compared under several conditions. The computer simulation results are shown.

This paper presents the design of a full-duplex multi-rate vocoder which implements an LPC-10, CELPC and VSELPC algorithms in real time. A single commercially available digital signal processor IC, the TMS320C25, is used to perform the digital processing. The channel interfaces are configured with the design of ASIC, and including timing and control logic circuits.

This paper presents a real-time implementation of 4.2Kb/s CELP speech coding on single DSP chip. An algorithm reducing search complexity for adaptive codebook is suggested; the solving method that the parameters are changed into LSP parameters is discussed. The realtime implementation process of this coding on a commercial development board with a single TMS320C30 is described.

A new scheme is presented to design a rotated Barnes-Wall lattice based vector quantizer(LVQ). The construction method of the LVQ and its, fast quantizing algorithm are described at first. Then gain-shape lattice vector quantizer (GSLVQ) with LVQ as shape quantizer is discussed. Finally the GSLVQ is used in image-sequence coding and good experimental results are obtained.

The paper discusses the architecture of an experimental research prototype for a microwave ATM customer premises network (CPN). Based on the architecture of the CPN, some of the key technologies for realizing the CPN functional blocks are discussed and part of the application specific integrated circuit (ASIC) design results are reported. >

This paper presents a Delaunay triangulation (DT) model-based multiresolution image representation of irregular triangles. After "minimizing the difference" and "minimizing the variance" criteria for image representation are given, splitting and merging methods for DT meshes are then discussed. Comparison of the two criteria is made with the aid of examples. The method demonstrated in the paper can be applied to still image coding, motion compensation for active image sequences and other image processing applications.

In MELP coder, LPC coefficients are quantized to 25 bit/frame by MSVQ. The overall bit of MELP is 54 bit/frame, so more than 45% of the required bandwidth is spent on transmission of LPC coefficients. In this paper, based on LPC adaptive forward-backward quantization, a novel variable-rate MELP coder is proposed, in which linear prediction is done by using either the currently (forward LPC) or previously decoded (backward LPC) speech frame. The backward LPC scheme shall be applied, i.e., the LPC coefficients based on the previously decoded optimal speech frame are used to encode the current frame and only the time delay shall be transmitted to the decoder, so, average LPC bit number becomes smaller. Computer simulation shows significant average overall bit rate reduction is achieved without compromising the decoded speech quality.

A brief history of telecommunications in China is given. The current status of telecommunication services, administration, technology, and policy is reviewed. Future plans are discussed. >

large bridge Josephson devices have been made of high Tc Y-Ba-Cu-O superconductors and Shapiro voltage stepts can be clearly seen when they are immersed in liquid nitrogen. A few of subharmonic steps appear. The devices have been cycled many times between 77K and 300K.

The new (1978) Chinese phonetic alphabet is introduced and rules are given for pronouncing Chinese names.