摘要:

One of the main and required characteristics of multimedia systems is the user‐interaction service. The user‐interaction service is an essential requirement in some applications, e.g., Video‐On‐Demand (VOD) and News‐On‐Demand (NOD). The user‐interaction service provides flexible multimedia presentations with user interactions. That is, users are allowed to have on‐line adjustment of the presentation flow, e.g., skip some (boring) media units or reverse the presentation direction, to have some special features. In this paper, we propose an Interactive Extended Finite State Machine (IEFSM) model to specify synchronization issues in multimedia presentations with user interactions. By incorporating interrupt transitions and dynamic transitions in the IEFSM model, dynamic behaviors resulting from user interactions can be modeled using some IEFSMs. Using the IEFSM model, intra‐medium synchronization is handled by an Actor, which is formally represented as an IEFSM; inter‐media synchronization is handled by a Synchronizer, which is also formally represented as an IEFSM. The communication between IEFSMs is message‐passing through some First‐In‐First‐Out (FIFO) queues. In this way, the dynamic behaviors of user interactions, including reverse, skip, freeze‐restart, and scale can be represented in IEFSM‐based multimedia synchronization specifications.

ISSN:0253-3839    

DOI:10.1080/02533839.1998.9670389

出版商:Taylor & Francis Group    

年代:1998

数据来源: Taylor

摘要:

A switch‐level timing simulator has the advantage of fast speed and good adaptability for VLSI circuits, but it cannot offer accurate transient waveform information. In this paper an accurate and efficient switch‐level timing simulator is described. The high accuracy is attributed to a new waveform approximation technique, which includes delay estimation and slope estimation. Efficient delay and slope calculations are accomplished through a switch‐level simulation instead of using a transistor‐level simulation. A new approach for delay estimation is presented which models the delay behavior of an RC tree by two equations: a dominant delay equation and an error delay equation. Both are derived by surface fitting to approximate the surface that is measured from the actual delay behavior of a CMOS gate. A modified approach for slope estimation is also investigated which has close relationship with the equivalent RC time constant of the evaluated cluster circuit. This equivalent RC time constant can be obtained by traversing the tree recursively. The results show good agreement with SPICE.

ISSN:0253-3839    

DOI:10.1080/02533839.1998.9670390

出版商:Taylor & Francis Group    

年代:1998

数据来源: Taylor

摘要:

Caches, data path, and burst transfer memory are the major hardware techniques used to reduce the latency between the processor and the main memory. We explore the design space among the hit ratio (hence a cache size, or an improved cache structure), data path width, and the transfer memory design through a performance tradeoff methodology. For the tradeoffs among these three factors, our evaluation shows that if a D‐byte data path system and a 2D‐byte data path system have the same performance, then the hit ratio difference that trades the performance of a D‐byte wide data path is between 0 (low bound) and1‐HR(high bound) whereHRis the hit ratio associated with the D‐byte system. For current main memory systems, doubling the data path trades about half of the high bound of the hit ratio traded in a transfer‐time dominated system. Doubling the data bus is more advantageous when the processor is designed with the use of a high‐speed non‐constant‐time‐dominated L2 cache. Doubling the bus width trades a large percentage of the hit ratio when a large amount of non‐cacheable 2D‐byte memory traffic exists.

ISSN:0253-3839    

DOI:10.1080/02533839.1998.9670391

出版商:Taylor & Francis Group    

年代:1998

数据来源: Taylor

摘要:

Expressions forϵ‐entropy rate, ϵ‐mutual information rate and ϵ‐divergence rate are introduced. These quantities, which consist of the quantiles of the asymptotic information spectra, generalize the inf/sup‐entropy/information/divergence rates of Han and Verdú. The algebraic properties of these information measures are rigorously analyzed, and examples illustrating their use in the computation of the e‐capacity are presented. In Part II of this work, these measures are employed to prove general source coding theorems for block codes, and the general formula of the Neyman‐Pearson hypothesis testing type‐II error exponent subject to upper bounds on the type‐I error probability.

ISSN:0253-3839    

DOI:10.1080/02533839.1998.9670392

出版商:Taylor & Francis Group    

年代:1998

数据来源: Taylor

摘要:

In light of the information measures introduced in Part I, a generalized version of the Asymptotic Equipartition Property (AEP) is proved. General fixed‐length data compaction and data compression (source coding) theorems for arbitrary finite‐alphabet sources are also established. Finally, the general expression of the Neyman‐Pearson type‐II error exponent subject to upper bounds on the type‐I error probability is examined.

ISSN:0253-3839    

DOI:10.1080/02533839.1998.9670393

出版商:Taylor & Francis Group    

年代:1998

数据来源: Taylor

摘要:

This work presents three novel signal processing methods capable of accurately detecting the optical phase delay in optical inter‐ferometric sensors. In the proposed methods, a triangular waveform modulation signal is used to modulate the optical phase of an optical interferometer for measuring optical phase delay. The optical phase delay in the first method is obtained by integrating the interferometric output signals with the gated‐in signal. The optical phase delay in the second method can be measured from the time delay difference between the interferometric signals during the gated‐in period. For the third method, the pseudo‐heterodyne technique is applied, and the optical phase delay is measured from the phase difference between two output signals. Moreover, a fiber Sagnac interferometric rotation sensor is adopted to demonstrate the effectiveness of the proposed methods. Furthermore, experimental results confirm that the proposed methods have an extreme degree of sensitivity and good linearity.

ISSN:0253-3839    

DOI:10.1080/02533839.1998.9670394

出版商:Taylor & Francis Group    

年代:1998

数据来源: Taylor

摘要:

The reaction of carbon disulfide and o‐phenylene diamine catalyzed by tertiary amine in the presence of KOH in an aqueous solution/ organic solvent two‐phase medium was carried out. The reaction was greatly enhanced by adding a small amount of tertiary amine in the presence of KOH. The reaction of synthesizing 2‐mercaptoben‐zimidazole (MBI) first took place in the organic phase. However, the potassium salt of MBI, which was produced from the reaction of MBI and KOH at the interface between CH2Cl2and H2O, dissolved in the aqueous phase. The greatest advantage of using this process is that MBI in crystal form can then be precipitated from the aqueous solution by adding an acidic compound. Based on the experimental data, a reaction mechanism was proposed. The reaction of synthesizing MBI was first initiated by reacting CS2and R3N to produce an active intermediate (R3N‐CS2). This active intermediate further reacted with o‐phenylene diamine to produce the desired MBI product. In addition, potassium hydroxide also reacted with H2S, which is a byproduct from the synthesis of MBI, to enhance the reaction. The reaction of CS2and CGH4(NH2)2in a two‐phase medium is described by a pseudo‐first‐order rate law.

ISSN:0253-3839    

DOI:10.1080/02533839.1998.9670395

出版商:Taylor & Francis Group    

年代:1998

数据来源: Taylor

摘要:

This research employs the tabu search method to develop an algorithm for efficiently solving concave cost transportation network problems which are characterized as NP‐hard. An initial solution method and a linear approximation approach are also developed, to evaluate the algorithm. The preliminary results show that the algorithm is potentially useful.

ISSN:0253-3839    

DOI:10.1080/02533839.1998.9670396

出版商:Taylor & Francis Group    

年代:1998

数据来源: Taylor

摘要:

This paper describes a database application generator for the WWW called GWB. GWB contains a compact language that adds control structures and database access constructs to HTML, a compiler that translates HTML‐like source templates into ODBC code and utilities for authentication and session management. It is designed to ease the expertise requirement needed for developing Web‐based intranet and internet database applications. This paper surveys the current approaches; describes the language and its support for authentication and session management; and gives an internet application using GWB. This paper also discusses future enhancement in terms of persistent database connections and server‐side client state persistency.

ISSN:0253-3839    

DOI:10.1080/02533839.1998.9670397

出版商:Taylor & Francis Group    

年代:1998

数据来源: Taylor

摘要:

In this paper, the method of modal analysis is presented to study the random vibration of multi‐span Mindlin plates due to a load moving at a constant velocity. The moving load is considered to be a stationary process with a constant mean value and a variance. Four types of variances are considered in this study: white noise, exponential, exponential cosine, and cosine. The effect of both velocity and statistical characteristics of the load, and the effect of the span number of the multi‐span plate on the mean value, variance of deflection and moment of the structure are investigated. The results of the multi‐span Mindlin plate are compared with those of a multi‐span classical plate.

ISSN:0253-3839    

DOI:10.1080/02533839.1998.9670398

出版商:Taylor & Francis Group    

年代:1998

数据来源: Taylor