21251487
Pipelined Implementation of TCAM-Based Search Engines in High-Performance IP Routers
Search engine is a critical component in several stages of a pipeline flow in high-performance IP routers. To achieve high performance, it has been proposed to use TCAMs to implement search engines in hardware. In this paper, the state- of-art TCAM-based MSMB-LPT scheme is used as an example to show how to introduce pipelining into TCAM-based search by presenting pipelined scheme P-MSMB-LPT. It is shown that P-MSMB-LPT eliminates the unnecessary hazard that exists in the MSMB-LPT scheme, and achieves near-optimal speedup with almost no additional hardware overhead.
18580310
1-Persistent Collision-Free CSMA Protocols for Opportunistic Optical Hyperchannels
Recently, a new WDM optical network infrastructure named SMART [1], which is capable of dynamically setting up, modifying, and tearing down optical connections, was proposed. The performance of SMART is determined by the performance of its hyperchannels, which are essentially optical buses or light-trails. Previously proposed CSMA protocols for unidirectional optical buses can be used as distributed medium access control protocols for hyperchannels. However, these protocols are either unfair, or not work-conserving. In this paper, we propose a class of work-conserving, collision-free, and fair CSMA protocols for opportunistic hyperchannels which are tailored hyperchannels for SMART. We show that the performances of our proposed protocols are much better than that of p i -persistent CSMA and that of priority-based CSMA protocol in terms of throughput and fairness.
2034529
Maximizing Throughput of an Optical Opportunistic Hyperchannel Subject to QoS Constraint
Opportunistic hyperchannel was proposed as an improvement of light-trail to carry IP traffic over wavelength division multiplexing (WDM) optical networks given its capability of enabling high speed provisioning and accommodating multi- granularity traffic. In an opportunistic hyperchannel, the optical shutters at the start node and the end node are configured to be in OFF state and the optical shutters at the intermediate nodes can be self-adjusted to be in ON/OFF according to actual traffic. With this ability, an opportunistic hyperchannel can be dynamically divided into multiple segments, and each segment can independently accommodate a request. Thus, an opportunistic hyperchannel can amplify the system throughput. In this paper, we present a centralized dynamic scheduling protocol named prioritized maximum independent set (PMIS), and introduce a data structure called 2-dimensional priority search tree (2D-PST) that supports PMIS. With 2D-PST, one round of PMIS can be carried out in O(k . log n . log m) time to maximize the system throughput under the constraint of assuring quality of service (QoS) for opportunistic hyperchannels. The simulation results quantitatively demonstrate the effectiveness of PMIS protocol.
17432242
Opportunistic Optical Hyperchannel and Its Distributed QoS Assuring Access Control
Light-trail is proposed as a candidate to carry IP traffic over wavelength-division multiplexing optical networks given its capability of enabling high-speed provisioning and accommodating multigranularity traffic. In a light-trail, the optical shutters at the start node and the end node are configured to be in OFF state and the optical shutters at the intermediate nodes are configured to be in ON state. Thus, an optical bus is formed, allowing traffic multiplexing without the state change of any optical shutter. This, however, limits the system throughput and also makes it impossible to implement a fully distributed medium access control (MAC) protocol to assure quality of service (QoS) in a light-trail. With the recent development on ultrafast optical shutter, we propose an improved light-trail architecture, called opportunistic hyperchannel in this paper. In an opportunistic hyperchannel, an intermediate node can dynamically control its optical shutter which makes it possible to design a fully distributed QoS assuring MAC protocol. We then present a QoS assuring distributed dynamic scheduling protocol, namely, minimum source round robin (minSrcRR) protocol, for opportunistic hyperchannels. Theoretical analysis on the effectiveness of the proposed QoS assuring protocol and the worst-case delay bound are also derived in this paper. The simulation results quantitatively demonstrate the advantage of opportunistic hyperchannels and the effectiveness of minSrcRR protocol.
18521632
Mining Most General Multidimensional Summarization of Probably Groups in Data Warehouses
Data summarization is an important data analysis task in data warehousing and online analytic processing. In this paper, we consider a novel type of summarization queries, probable group queries , uch as “What are the groups of patients that have a50% or more opportunity to get lung cancer than the average?” An aggregate cell satisfying the requirement is called aprobable group . To make the answer succinct and effective, we propose that only the most general probable groups should be mined. For example, if both groups (smoking, drinking) and (smoking, *) are probable, then the former groups should not be returned. The problem of mining the most general probable groups is challenging since the probable groups can be widely scattered in the cube lattice, and do not present any monotonicity in group containment order. We extend the state-of-the-art BUC algorithm to tackle the problem, and develop techniques and heuristics to speed up the search. An extensive performance study is reported to illustrate the effect of our approach.
11674689
Integrated Cell-based Biosensor for Extracellular Electrophysiological Monitoring
A rigorous preselection of identified compounds by in vitro cellular screening is necessary prior to using the drug candidates for the further time consuming and parallel monitoring stage. In this paper we introduced an integrated cell based chip which can detect changes of electrophysiological parameters by using microelectronic chips such as light-addressable potentiometric sensors(LAPS), micro-electrodes array sensors(MEAS) and interdigitated array sensor(IDA) etc. to record the extracellular metabolism chemical and biological substances, action potential and living characteristics of cells representing the different response. In this research we presented novel ideas including an integrating multifunctional cell sensors chip, obtaining the living cells as the source of cell sensors with cardiac myocytes. Further developments will be done by culturing living olfactory and taste cells on surface of the devices. Now, we have completed the fabrication of the sensor and obtained some promising experiments results in different sensor units. This research will be interesting and useful for parallel extracellular monitoring.
16456710
News Summarization Based on Semantic Similarity Measure
This paper proposed a new method of news summarization based on semantic similarity measure. It used Latent semantic indexing (LSI) to measure sentence similarity, then it used Singular Value Decomposition (SVD) to reduce the dimension of the word-sentence matrix, it used new clustering algorithm to cluster all the sentences. It ordered all the sentences according to their relevant positions in the original document. Experimental result shows that the proposed method can improve the performance of summary.
14824084
News Video Retrieval by Learning Multimodal Semantic Information
With the explosion of multimedia data especially that of video data, requirement of efficient video retrieval has becoming more and more important. Years of TREC Video Retrieval Evaluation (TRECVID) research gives benchmark for video search task. The video data in TRECVID are mainly news video. In this paper a compound model consisting of several atom search modules, i.e., textual and visual, for news video retrieval is introduced. First, the analysis on query topics helps to improve the performance of video retrieval. Furthermore, the multimodal fusion of all atom search modules ensures to get good performance. Experimental results on TRECVID 2005 and TRECVID 2006 search tasks demonstrate the effectiveness of the proposed method.
28503977
Adoption of Cognitive Radio Scheme to Class-Based Call Admission Control
By using cognitive radio technology, opportunistic spectrum access has the potential to solve the underused spectrum problem. In this paper, by first introducing a specific cognitive radio scheme, we analyze the secondary user's capacity and the collision probability. Employing this scheme, we build two call admission control models for three classes of service, namely, handoff voice calls, new voice calls and data calls. We show that they achieve improved blocking probability and throughput by exploiting the cognitive radio scheme. Further, we show a tradeoff between collision probability and blocking/throughput in the call admission control.