ppxscal/embedding_network huggingface dataset:
Mining Closed and Maximal Frequent Induced Free Subtrees
Authors: Hitohiro Shiozaki, Tomonobu Ozaki, Takenao Ohkawa
Venue: Proceedings of the Sixth IEEE International Conference on Data Mining - Workshops (2006)

Mining frequent tree patterns is an important problem, since tree structures are used in various fields such as computational biology, XML databases, and so on. However, mining all frequent subtrees is sometimes infeasible because of the combinatorial explosion. In this paper, by combining an efficient algorithm for enumerating free trees and the pruning techniques for mining closed and maximal rooted trees, we present an efficient algorithm named CMFree- TreeMiner that discovers only closed and maximal frequent induced free subtrees in a database of labeled free trees. Experimental results show the effectiveness of the proposed algorithm.
An Analysis of Hashing on Parallel and Vector Computers
Authors: Thomas J. Sheffler, Randal E. Bryant
Venue: Proceedings of the 1993 International Conference on Parallel Processing - Volume 03 (1993)

Parallel hashing is well-known in the folklore of parallel computing, but there has been a remarkable dearth of literature describing it in detail. Because many parallel algorithms such as histogramming, set intersection and dictionary lookup can make use of hashing as a core step, hashing is a fundamental parallel operation. This paper sheds light on the performance that may be achieved using parallel hashing algorithms and should lend credibility to their use.
Detecting BGP configuration faults with static analysis
Authors: Nick Feamster, Hari Balakrishnan
Venue: Proceedings of the 2nd conference on Symposium on Networked Systems Design & Implementation - Volume 2 (2005)

The Internet is composed of many independent autonomous systems (ASes) that exchange reachability information to destinations using the Border Gateway Protocol (BGP). Network operators in each AS configure BGP routers to control the routes that are learned, selected, and announced to other routers. Faults in BGP configuration can cause forwarding loops, packet loss, and unintended paths between hosts, each of which constitutes a failure of the Internet routing infrastructure. This paper describes the design and implementation of rcc, the router configuration checker, a tool that finds faults in BGP configurations using static analysis. rcc detects faults by checking constraints that are based on a high-level correctness specification. rcc detects two broad classes of faults: route validity faults, where routers may learn routes that do not correspond to usable paths, and path visibility faults, where routers may fail to learn routes for paths that exist in the network. rcc enables network operators to test and debug configurations before deploying them in an operational network, improving on the status quo where most faults are detected only during operation. rcc has been downloaded by more than sixty-five network operators to date, some of whom have shared their configurations with us. We analyze network-wide configurations from 17 different ASes to detect a wide variety of faults and use these findings to motivate improvements to the Internet routing infrastructure.
Hidden Markov models for monitoring machining tool-wear
Authors: L. Atlas
Venue: Proceedings of the Acoustics, Speech, and Signal Processing, 2000. on IEEE International Conference - Volume 06 (2000)

As summarized by Atlas, Bernard, and Narayanan (1996), the sensing of acoustic vibrations can remotely estimate the state of wear at the tool edge. This form of monitoring offers the potential to characterize, in real time, the efficiency of metal removal processes such as drilling and milling. For example, information about sudden increases in tool wear, if manifest as a change in acoustic vibration, could be valuable to a machine operator. The nature of this monitoring problem has some similarities to automatic speech recognition. For example, there is significant tool-to-tool variation in details of vibration and lifetime. Also, the easy adaptability of monitoring systems across manufacturing processes is important. In this work we model the evolution of vibration signals with the same technique which has shown to be successful in speech recognition: hidden Markov models (HMMs). We focus on the monitoring of milling processes at three different time scales and show the how HMMs can give accurate wear prediction.
Variable size finite-state motion vector quantization
Authors: A. Bilgin
Venue: Proceedings of the Acoustics, Speech, and Signal Processing, 1996. on Conference Proceedings., 1996 IEEE International Conference - Volume 04 (1996)

We present an algorithm which combines vector quantization (VQ) techniques with variable size block matching algorithms (BMA) for motion compensated image sequence coding. First, an algorithm which decomposes the image frame into blocks of different sizes with similar motion parameters is proposed. Since the algorithm is based on splitting the block that would result in the highest decrease in distortion, it does not require a merging step. Next, VQ techniques are utilized to expedite the search for the block motion vector without significant sacrifice in the temporal entropy reduction performance. We compare the performance and the computational requirements of the proposed algorithm with other BMAs.
Design and Implementation of an Open Programmable Router Compliant to IETF ForCES Specifications
Authors: Weiming Wang, Ligang Dong, Bin Zhuge, Ming Gao, Fenggen Jia, Rong Jin, Jin Yu, Xiaochun Wu
Venue: Proceedings of the Sixth International Conference on Networking (2007)

IETF ForCES (Forwarding and Control Element Separation) is defining specifications for interfaces and modular resources abstractions of network equipments. ForCES brings flexible, programmable, and cost-effective advantages over tradi-tional architectures for network equipments. In this paper, the design and implementation of a ForCES-based router (ForTER) was illustrated. The framework of ForCES was introduced firstly. Then a layered model for the implementation of ForTER was presented. Next, the implementation details of Control Ele-ment (CE) and Forwarding Element (FE) of ForTER were intro-duced, which complied with the ForCES framework and related IETF ForCES specifications. Finally, results of experiments for routing and for SNMP support showed the feasibility of the sys-tem architecture of ForTER, which also fundamentally testified the feasibility of ForCES and related specifications that are being standardized by IETF ForCES working group.
High performance Chinese OCR based on Gabor features, discriminative feature extraction and model training
Authors: Qiang Huo
Venue: Proceedings of the Acoustics, Speech, and Signal Processing, 2001. on IEEE International Conference - Volume 03 (2001)

We have developed a Chinese OCR engine for machine printed documents. Currently, our OCR engine can support a vocabulary of 6921 characters which include 6707 simplified Chinese characters in GB2312-80, 12 frequently used GBK Chinese characters, 62 alphanumeric characters, 140 punctuation marks and symbols. The supported font styles include Song, Fang Song, Kat, He, Yuan, LiShu, WeiBei, XingKai, etc. The averaged character recognition accuracy is above 99% for newspaper quality documents with a recognition speed of about 250 characters per second on a Pentium III-450 MHz PC yet only consuming less than 2 MB memory. We describe the key technologies we used to construct the above recognizer. Among them, we highlight three key techniques contributing to the high recognition accuracy, namely the use of Gabor features, the use of discriminative feature extraction, and the use of minimum classification error as a criterion for model training.
Context-Aware Elevator Scheduling
Authors: Thomas Strang, Christian Bauer
Venue: Proceedings of the 21st International Conference on Advanced Information Networking and Applications Workshops - Volume 02 (2007)

Research on context-aware systems is usually user-centric and thus focussed on the context of a specific user to serve his or her needs in an optimized way. In this paper, we want to apply core concepts developed in research on context-awareness in a system-centric way, namely to elevator systems. We show with three different examples that the performance of an elevator system can be significantly improved if the elevator control has access to contextual knowledge. The first example demonstrates that an appropriate elevator group scheduling algorithm can be chosen and adjusted to the current and near-future passenger traffic situation. The second example incorporates a second predominant technology used in many ubiquitous computing environments, namely RFID tags, to predict the passengers destination. The third example shows that adaptation to a specific emergency situation can further increase the transportation capacity of an elevator system which is ultimately important to save as many lifes as possible in an emergency. Evidence for the increased efficiency is provided by using a comprehensive simulation of a diverse set of scheduling algorithms and scenarios.
Highly efficient signal processing for frequency agile power line communications
Authors: M. Sliskovic
Venue: Proceedings of the Acoustics, Speech, and Signal Processing, 1999. on 1999 IEEE International Conference - Volume 05 (1999)

A modified frequency hopping signaling scheme has received considerable attention by the designers of power line communication systems because of its insensitivity to frequency selective and time-variant attenuation and high level of interference. In a frequency hopping system, the increase of the data rate without an increase of the hop rate is possible only if the receiver can detect all information-bearing tones simultaneously. This paper presents the structure of the noncoherent optimum receiver that minimizes the number of required multiplications and memory locations. The receiver structure is based on the computation of equidistant DFT coefficients. The proposed demodulator can be used in systems with variable bit rate. With a slightly modified algorithm, rough synchronization can also be achieved. A comparison of the computational complexity confirms the superiority of the presented algorithm over direct DFT calculation and FFT algorithm. The ACM Portal is published by the Association for Computing Machinery. Copyright © 2010 ACM, Inc. Terms of Usage Privacy Policy Code of Ethics Contact Us Useful downloads: Adobe Acrobat QuickTime Windows Media Player Real Player
An efficient algorithm for characteristic tracking on two-dimensional triangular meshes
Authors: J. Liu, H. Chen, R. Ewing, G. Qin
Venue: Computing (2007)

Tracking characteristics on unstructured meshes is an important part of many numerical methods in computational fluid mechanics. In this paper, we propose an efficient algorithm for characteristic tracking on two-dimensional unstructured triangular meshes. Numerical experiments, including an example for applying this algorithm with the Eulerian-Lagrangian localized adjoint method (ELLAM) to solve a convection-dominated convection-diffusion problem, are presented to demonstrate the efficiency of this algorithm.
Performance Evaluation of Security Services: An Experimental Approach
Authors: Alessandro Cilardo, Luigi Coppolino, Antonino Mazzeo, Luigi Romano
Venue: Proceedings of the 15th Euromicro International Conference on Parallel, Distributed and Network-Based Processing (2007)

Recent advances in wireless technologies have enabled pervasive connectivity to Internet scale systems which include heterogeneous mobile devices, such as mobile phones and Personal Digital Assistants, a trend which is generally referred to as ubiquitous computing. This leads to the need for providing security functions to applications which are partially deployed over wireless devices. Delivering security services to mobile devices raises a number of challenging issues, mostly related to the limited amount of computing power which is typically available on the target platforms. Some promising solutions rely on multi-tier architectures, which are based on the emerging Web Services technology. In this scenario, understanding the impact of architectural characteristics of specific platforms is a key issue for practitioners who have to develop and deploy efficient security-enabled applications on mobile devices. This paper provides an experimental study of the impact that specific characteristics of individual mobile device platforms have on the final performance of security applications. Focus is on performance and resource utilization, which are key aspects when one develops applications on mobile devices. The case study is a Web Services based solution for delivering Public Key Infrastructure (PKI) Services to Mobile Devices. Experiments have been conducted on three different mobile terminals, which span a large range of characteristics in the class of resource-constrained devices. Results show that: i) performance figures are not uniform in spite of similar underlying hardware characteristics, and ii) security and performance are often conflicting requirements.
ACPI4Linux
Authors: Max Berger
Venue: Proceedings of the 3rd annual conference on Atlanta Linux Showcase - Volume 3 (1999)

This document gives an overview of Advanced Configuration and Power interface (ACPI), often referred to as successor of APM. The issues of power management are described. This includes Global States, Sleeping States, Device States and CPU states. Sleeping, suspending, hibernation and shutdown is explained, also thermal management, especially the difference between active cooling and passive cooling, performance mode and silence mode. The Plug'n'Play model of ACPI is introduced. An overview of ACPI control method Machine Language (AML) and ACPI control method Source Language (ASL) is given. The ACPI implementations of Linux are described: The User-Kernel interface, the new memory management with memory holes, APM compatibility, the AML virtual machine, and a short report about ACPI4Linux status.
Efficient support for P-HTTP in cluster-based web servers
Authors: Mohit Aron, Peter Druschel, Willy Zwaenepoel
Venue: Proceedings of the annual conference on USENIX Annual Technical Conference (1999)

This paper studies mechanisms and policies for supporting HTTP/1.1 persistent connections in cluster-based Web servers that employ content-based request distribution. We present two mechanisms for the efficient, content-based distribution of HTTP/1.1 requests among the back-end nodes of a cluster server. A trace-driven simulation shows that these mechanisms, combined with an extension of the locality-aware request distribution (LARD) policy, are effective in yielding scalable performance for HTTP/1.1 requests. We implemented the simpler of these two mechanisms, back-end forwarding. Measurements of this mechanism in connection with extended LARD on a prototype cluster, driven with traces from actual Web servers, confirm the simulation results. The throughput of the prototype is up to four times better than that achieved by conventional weighted round-robin request distribution. In addition, throughput with persistent connections is up to 26% better than without.
Vocoder intelligibility and quality test methods
Authors: J. D. Tardelli
Venue: Proceedings of the Acoustics, Speech, and Signal Processing, 1996. on Conference Proceedings., 1996 IEEE International Conference - Volume 02 (1996)

The U.S. Department of Defense's Digital Voice Processing Consortium (DDVPC) is in the process of choosing a new 2400 bps vocoder standard. As part of the selection process, a study was conducted to determine the test measures to be used for the evaluation of the intelligibility and quality of competing vocoder algorithms. The DDVPC requirements for a vocoder differ substantially from commercial interests. Severe ambient acoustic noise backgrounds coupled with hostile transmission channel conditions must be considered. The commercially popular mean opinion score (MOS) test method was evaluated as a replacement or companion test of quality to the diagnostic acceptability measure (DAM), traditionally used by the DDVPC. The study showed that a properly structured MOS test can achieve equal resolution, reliability, and validity to that of the DAM at equivalent costs. Any MOS test series must be structured to minimize contextual effects. Certain severe conditions must use the degraded mean opinion score (DMOS) test method to achieve usable resolution.
Proceedings of the 7th ACM/IEEE-CS joint conference on Digital libraries
Venue: International Conference on Digital Libraries (2007)

Welcome to JCDL 2007! It is our great pleasure to welcome you to the 7th annual meeting of the ACM/IEEE Joint Conference on Digital Libraries (JCDL). JCDL is one of the primary international forums for the presentation and discussion of research, practice and social issues related to digital libraries. The conference theme this year is "Building and Sustaining the Digital Environment" and the program reflects these themes as well as the broader context of digital libraries and the boundary spanning research that supports their design, development and operation. This year we had a record number of submissions for the conference with 279 total submissions from digital library researchers in 31 countries. From 119 Full papers submissions and 68 short paper submissions the program committee selected 43 Full papers and 28 Short papers for presentation at the conference. In addition, 30 posters and 14 demonstrations were selected for presentation at the special poster and demo evening session. As in previous years we will be awarding the Vannevar Bush Best Paper Award (sponsored by ACM). In addition to the main meeting, a full schedule of tutorials and workshops has been arranged bracketing the main meeting. This year we also host the largest Doctoral Consortium yet held at JCDL, where student researchers in digital library topics work with an international panel of faculty mentors on exploring and refining their thesis research.
MavEStream: Synergistic Integration of Stream and Event Processing
Authors: Qingchun Jiang, Raman Adaikkalavan, Sharma Chakravarthy
Venue: Proceedings of the Second International Conference on Digital Telecommunications (2007)

Although research seems to address event and stream data processing as two separate topics, there are a number of similarities between them. For many advanced stream applications, both event and rule processing are needed and are not currently well-supported. Extant event processing systems concentrate primarily on complex events and rules and stream processing systems concentrate on stream operators, scheduling, and quality of service issues. Synergistic integration of these models will be better than the sum of its parts. We propose an integrated model to combine the capabilities of both models for applications that need both of them. Specifically, we introduced a number of enhancements, including stream modifiers, semantic windows, event generators, and enhanced event and rule specifications, to couple two models seamlessly. We prototype our integrated system using the stream processing system (MavStream) with the event processing system (Snoop and Sentinel) and discuss the design and implementation issues of our prototype.
Soft-Errors Phenomenon Impacts on Design for Reliability Technologies
Authors: Mark Derbey
Venue: Proceedings of the 13th IEEE International On-Line Testing Symposium (2007)

We will mainly address here the "alter ego" of quality, which is reliability, and is becoming a growing concern for designers using the latest technologies. After the DFM nodes in 90nm and 65nm, we are entering the DFR area, or Design For Reliability straddling from 65nm to 45nm and beyond. Because of the randomness character of reliability - failures can happen anytime anywhere - executives should mitigate reliability problems in terms of risk, which costs include cost of recalls, warranty costs, and loss of goodwill.
Interstatement must aliases for data dependence analysis of heap locations
Authors: Ju Qian, Baowen Xu, Hongbo Min
Venue: Proceedings of the 7th ACM SIGPLAN-SIGSOFT workshop on Program analysis for software tools and engineering (2007)

Data dependences are of critical importance in many software engineering activities. Due to the dynamic allocation mechanism, it is still difficult to extract them precisely for heap locations. This paper firstly proposes two notion of interstatement must aliases and then exploits these aliases in improving data depend-ence analysis for heap locations. We carry out a preliminary ex-periment on some programs, the result of which indicates that the new technique can effectively improve the precision of depend-ence analysis for heap locations with an endurable cost.
An analysis of the garbage collection performance in Sun's HotSpot/sup TM/ Java Virtual Machine
Authors: L. Dykstra
Venue: Proceedings of the Performance, Computing, and Communications Conference, 2002. on 21st IEEE International (2002)

Sun Microsystems introduced the Java HotSpot Virtual Machine as a high performance engine for the Java programming language. The improvements over the classic Java Virtual Machine include dynamic compilation and optimization, better thread synchronization, and a more sophisticated and fully accurate garbage collection system. In this paper, a thorough analysis of the dynamic memory management issues in the HotSpot VM are performed. The analysis includes the memory allocation latency, the workload distribution, overall garbage collection time, and the pause times. The results indicate that the HotSpot VM succeeds in reducing the pause times by approximately 80%. However, it may prolong the overall garbage collection time in some applications.
Compressed Materialised Views of Semi-Structured Data
Authors: Richard Gourlay, Brian Tripney, John Wilson
Venue: Proceedings of the 24th British National Conference on Databases (2007)

Query performance issues over semi-structured data have led to the emergence of materialised XML views as a means of restricting the data structure processed by a query. However preserving the conventional representation of such views remains a significant limiting factor especially in the context of mobile devices where processing power, memory usage and bandwidth are significant factors. To explore the concept of a compressed materialised view, we extend our earlier work on structural XML compression to produce a combination of structural summarisation and data compression techniques. These techniques provide a basis for efficiently dealing with both structural queries and valuebased predicates. We evaluate the effectiveness of such a scheme, presenting results and performance measures that show advantages of using such structures.