ppxscal/embedding_network huggingface dataset:
On the Sequencing of Tree Structures for XML Indexing
Authors: Haixun Wang, Xiaofeng Meng
Venue: Proceedings of the 21st International Conference on Data Engineering (2005)

Sequence-based XML indexing aims at avoiding expensive join operations in query processing. It transforms structured XML data into sequences so that a structured query can be answered holistically through subsequence matching. In this paper, we address the problem of query equivalence with respect to this transformation, and we introduce a performance-oriented principle for sequencing tree structures. With query equivalence, XML queries can be performed through subsequence matching without join operations, post-processing, or other special handling for problems such as false alarms. We identify a class of sequencing methods for this purpose, and we present a novel subsequence matching algorithm that observe query equivalence. Still, query equivalence is just a prerequisite for sequence-based XML indexing. Our goal is to find the best sequencing strategy with regard to the time and space complexity in indexing and querying XML data. To this end, we introduce a performance-oriented principle to guide the sequencing of tree structures. For any given XML dataset, the principle finds an optimal sequencing strategy according to its schema and its data distribution. We present a novel method that realizes this principle. In our experiments, we show the advantages of sequence-based indexing over traditional XML indexing methods, and we compare several sequencing strategies and demonstrate the benefit of the performance-oriented sequencing principle.
QoS-Oriented Hybrid Admission Control in IEEE 802.11 WLAN
Authors: Changhua Zhu, Changxing Pei, Jiandong Li, Weidong Kou
Venue: Proceedings of the 19th International Conference on Advanced Information Networking and Applications - Volume 1 (2005)

A new QoS (Quality of Services)-oriented Hybrid Admission Control (QHAC) scheme in IEEE 802.11 WLAN is proposed, in which the influence of the mobile station with slow speed on other stations is decreased by limiting its inter-request time. In addition, end-to-end performance metrics are also measured and applied to make a decision to admission control of new request. Simulation results show that QHAC scheme can efficiently improve the performance of IEEE 802.11 WLAN.
xSADL: An Architecture Description Language to Specify Component-Based Systems
Authors: Shifeng Zhang, Steve Goddard
Venue: Proceedings of the International Conference on Information Technology: Coding and Computing (ITCC'05) - Volume II - Volume 02 (2005)

Software Architecture (SA) provides a formal basis to describe and analyze a software system as a collection of components and their interactions (connectors). However, the current understanding and specification for a connector are still insufficient. Furthermore, there still exists a gap between architecture design and component-based implementation. This paper attempts to tackle these problems by providing an Architecture Description Language (ADL), xSADL. In the specification of a connector, xSADL can help designers to deal with two kinds of architectural mismatches: behavior mismatch and message mismatch. xSADL is also supported by a GUI-based CASE tool. To help transform the architecture design by xSADL to a component-based software implementation, a component framework, 3CoFramework, is also introduced. xSADL and 3CoFramework complement each other and construct an architecture-based component development environment.
Facilitating Distributed Time-Triggered Simulation of Embedded Systems and Environments
Authors: K. H. (Kane) Kim, Stephen F. Jenks
Venue: Proceedings of the 19th IEEE International Parallel and Distributed Processing Symposium (IPDPS'05) - Workshop 10 - Volume 11 (2005)

The distributed time-triggered simulation (DTS) scheme is a new type of an approach to real-time simulation based on parallel / distributed computing. It requires a global time base which provides consistent real-time information to application software running on distributed nodes. The exploitation of its full potential requires advanced computing platforms such as highly parallel computing platforms. Recent developments in the scientific foundation for DTS and the execution engines and programming tools supporting DTS are briefly reviewed.
When is &ldquo;enough&rdquo; enough? Modeling the information-seeking and stopping behavior of senior arts administrators: Research Articles
Authors: Lisl Zach
Venue: Journal of the American Society for Information Science and Technology (2005)

Among managers, those who are responsible for nonprofit organizations in general and arts organizations in particular have been an understudied group. These managers have much in common with their for-profit counterparts, but their environment also differs in significant ways. The goal of this exploratory research effort was to identify how senior administrators in fine arts museums and symphony orchestras go about identifying and acquiring the information they want to complete a range of management tasks. Deciding when and where to look for information, obtaining the &ldquo;right&rdquo; information at the time it is needed, evaluating its credibility and utility, and determining when &ldquo;enough&rdquo; information has been collected are challenges facing this group of information users every day. A multiple-case studies design involving a replication strategy was selected to structure the research process. Data were collected from 12 arts administrators using a pretested interview protocol that included the Critical Incident Technique. Patterns in the data were identified, and the data were further reviewed for disconfirming evidence. The study resulted in a list of the types and sources of information that arts administrators use as well as a list of the factors or &ldquo;stopping criteria&rdquo; that influence them to end their information-seeking process. A model describing the way in which arts administrators go about acquiring the information they want was also developed. The main findings of the study are (a) arts administrators do not consider information seeking to be a discrete management task, (b) they rely heavily on direct personal experience to fill their information-seeking needs, and (c) they are &ldquo;satisficers&rdquo; when it comes to seeking information. Based on Simon's alternative to rational choice theory, satisficers are people who are willing to pursue a &ldquo;good enough&rdquo; option rather than the best possible option (maximizers) (Simon, 1956). Since arts administrators have not been studied in the context of LIS research before, understanding more about where they go for information, what factors influence the level of effort they are willing to invest in seeking information, and how they decide when they have &ldquo;enough&rdquo; information provides insights into the information-seeking behavior of a new user group. Furthermore, although this research effort is focused on specific users in a specific field, the results from this study may be compared to what we already know about other user groups to confirm and expand existing models of information-seeking behavior. &copy; 2005 Wiley Periodicals, Inc.
Sequences as a basis for pattern language composition
Authors: Ronald Porter, James O. Coplien, Tiffany Winn
Venue: Science of Computer Programming (2005)

Pattern languages have begun to appear and mature as a presentation of the structures and processes that support the building of complex software systems. A pattern language describes how to compose structures in a particular domain such as telecommunications, client-server architecture, or object-oriented programming, to achieve system-level architectures that are greater than the sum of their parts. A problem lurks on the horizon: How do you compose patterns from multiple domains--from multiple pattern languages--in a single system? For example, today there is nothing other than an ad hoc approach to combining the pattern languages for telecommunications and for object-oriented design to build object-oriented telecommunications systems from the respective pattern languages. To understand the solution to this dilemma, it pays to examine sequences: an important aspect of pattern application that is often overlooked. Sequences are the loci of concern about interleaving patterns, whether from a single pattern language or multiple pattern languages. Sequences are critical because pattern languages represent long-term archives of the rhythms of critical, recurring sequences.
Protocol synthesis and re-synthesis with optimal allocation of resources based on extended petri nets
Authors: Hirozumi Yamaguchi, Khaled El-Fakih, Gregor von Bochmann, Teruo Higashino
Venue: Distributed Computing (2003)

Protocol synthesis is used to derive a protocol specification, that is, the specification of a set of application components running in a distributed system of networked computers, from a specification of services (called the service specification) to be provided by the distributed application to its users. Protocol synthesis reduces design costs and errors by specifying the message exchanges between the application components, as defined by the protocol specification. In general, maintaining such a distributed application involves applying frequent minor modifications to the service specification due to changes in the user requirements. Deriving the protocol specification after each modification using the existing synthesis methods is considered expensive and time consuming. Moreover, we cannot identify what changes we should make to the protocol specification in correspondence to the changes in the service specification, in this paper, we present a new synthesis method to re-synthesize only those parts of the protocol specification that must be modified in order to satisfy the changes in the service specification. The method consists of a set of simple rules that are applied to the protocol specification written in an extended Petri net model. An application example is given along with some experimental results.
M-Task-Programming for Heterogeneous Systems and Grid Environments
Authors: Thomas Rauber, Gudula Runger
Venue: Proceedings of the 19th IEEE International Parallel and Distributed Processing Symposium (IPDPS'05) - Workshop 4 - Volume 05 (2005)

A task-parallel execution has been shown to be successful on homogeneous parallel systems for many applications providing a suitable degree of multiprocessor task parallelism. In this paper, we extend the model of task-parallel executions so that the same program can also be executed in heterogeneous systems and grid environments. The new model is particularly suited for large applications consisting of independent modules which can be mapped onto different parts of a distributed execution platform. We show that a suitable representation of the execution activities is crucial for combining a flexible multi-level specification with a dynamic scheduling that can be adapted to a dynamically changing execution environment. We also show how a collection of distributed task-managers organizes the distributed execution based on CORBA.
BMI: A Network Abstraction Layer for Parallel I/O
Authors: Philip Carns, Robert Ross, Walter Ligon III, Pete Wyckoff
Venue: Proceedings of the 19th IEEE International Parallel and Distributed Processing Symposium (IPDPS'05) - Workshop 9 - Volume 10 (2005)

As high-performance computing increases in popularity and performance, the demand for similarly capable input and output systems rises. Parallel I/O takes advantage of many data server machines to provide linearly scaling performance to parallel applications that access storage over the system area network. The demands placed on the network by a parallel storage system are considerably different than those imposed by message-passing algorithms or datacenter operations; and, there are many popular and varied networks in use in modern parallel machines. These considerations lead us to develop a network abstraction layer for parallel I/O which is efficient and thread-safe, provides operations specifically required for I/O processing, and supports multiple networks. The Buffered Message Interface (BMI) has low processor overhead, minimal impact on latency, and can improve throughput for parallel file system workloads by as much as 40% compared to other more generic network abstractions.
GHS: A Performance System of Grid Computing
Authors: Xian-He Sun, Ming Wu
Venue: Proceedings of the 19th IEEE International Parallel and Distributed Processing Symposium (IPDPS'05) - Workshop 10 - Volume 11 (2005)

Conventional performance evaluation mechanisms focus on dedicated distributed systems. Grid computing infrastructure, on another hand, is a shared collaborative environment constructed on autonomic virtual organizations. The non-dedicated characteristic of Grid computing prevents the leverage of conventional task scheduling systems. In this study, we present the design and development of the Grid Harvest Service (GHS) performance evaluation and task scheduling system for solving large-scale applications in a shared network environment. GHS combines stochastic models and artificial intelligence learning mechanisms with task scheduling algorithms. It considers both computing and network contention and supports scheduling for single task, parallel processing, and meta-tasks. Experimental results show that GHS provides a satisfactory solution for performance prediction and task scheduling and has a real potential.
A brief description of SPARSPAK Waterloo sparse linear equations package
Authors: Alan George, Esmond Ng
Venue: ACM SIGNUM Newsletter (1981)

Computer subroutines for solving large sparse systems of linear equations usually involve fairly complicated data structures and storage management. In most cases, the user of such subroutines simply wants top solve his problem and does not have to understand how the storage management is done, or how the matrix components are stored. Thus software for solving sparse systems of linear equations should be designed in such a way that it can insulate the user from these considerations, while still allowing the software to be used in a variety of ways.
Improving Disk Throughput in Data-Intensive Servers
Authors: Enrique V. Carrera, Ricardo Bianchini
Venue: Proceedings of the 10th International Symposium on High Performance Computer Architecture (2004)

Low disk throughput is one of the main impediments to improving the performance of data-intensive servers. In this paper, we propose two management techniques for the disk controller cache that can significantly increase disk throughput. The first technique, called File-Oriented Read-ahead (FOR), adjusts the number of read-ahead blocks brought into the disk controller cache according to file system information. The second technique, called Host-guided Device Caching (HDC), gives the host control over part of the disk controller cache. As an example use of this mechanism, we keep the blocks that cause the most misses in the host buffer cache permanently cached in the disk controller. Our detailed simulations of real server workloads show that FOR and HDC can increase disk throughput by up to 34% and 24%, respectively, in comparison to conventional disk controller cache management techniques. When combined, the techniques can increase throughput by up to 47%.
Managing inter-organisational workflows in eGovernment services
Authors: Devendra K. Punia, K. B. C. Saxena
Venue: Proceedings of the 6th international conference on Electronic commerce (2004)

E-government refers to the use of ICTs to promote more efficient and effective government services, allow greater public access to information and make government more accountable to citizens. Though e-government initiatives are common in most countries, getting the claimed benefits of e-government has not been easy for various technological as well as organisational reasons. In addition to government structures and ICT systems, government processes have played a very significant role in bringing e-government success. Unfortunately most government services involve processes carried out by multiple government agencies and have poor performance due to poor coordination among various agencies. This paper analyses such inter-organisational processes (IOPs) for improving their workflows and develops a framework for workflow management in such processes. Further it describes the concept of 'public process' as an effective workflow management tool, and explains its application through a case study.
Information Assurance In Wireless Sensor Networks
Authors: Stephan Olariu, Qingwen Xu
Venue: Proceedings of the 19th IEEE International Parallel and Distributed Processing Symposium (IPDPS'05) - Workshop 12 - Volume 13 (2005)

Networking unattended wireless sensors is expected to have significant impact on the efficiency of a large array of military and non-military applications. The main goal of wireless sensor networks is to obtain globally meaningful information from strictly local gleaned by individual sensor nodes. The network is deployed such that the sensors are embedded, possibly at random, in a target environment. Utilizing the basic capabilities of sensor nodes in the network different types of monitoring and control applications that address the target environment can be developed. Depending on the application at hand, the interface between a sensor network and the outside world is provided by aircraft, helicopters, ground-based vehicles, satellites, co-located sink-nodes, etc. However, a wireless sensor network is only as good as the information it produces. In this respect, the most important concern is information assurance. Indeed, in most application domains sensor networks will constitute a mission critical component requiring commensurate security protection. Sensor network communications must prevent disclosure and undetected modification of exchanged messages. Due to the fact that individual sensor nodes are anonymous and that communication among sensors is via wireless links, sensor networks are highly vulnerable to security attacks. If an adversary can thwart the work of the network by perturbing the information produced, stopping production, or pilfering information, then the perceived usefulness of sensor networks will be drastically curtailed. Thus, security is a major issue that must be resolved in order for the potential of wireless sensor networks to be fully exploited.
Synthetic Simulation of Mesh-Based Parallel Applications Driven by Fine-Grained Profiling
Authors: Qingyuan Liu, Amol S. Deshmukh, Karen A. Tomko
Venue: Proceedings of the 19th IEEE International Parallel and Distributed Processing Symposium (IPDPS'05) - Workshop 15 - Volume 16 (2005)

We are interested in discovering the intrinsic dynamics of parallel applications, which are independent of runtime environment, to aid in the development of appropriate tuning policies, especially dynamic load balancing policies. Based on the novel idea of profiling mesh-based applications at a fine granularity of each mesh element, this paper proposes a synthetic application simulator which is driven by a series of application signatures mapping to the mesh structure. By integrating the ZOLTAN library into the system, our simulator provides a convenient test bed for developing and evaluating load balancing policies.
Improving the performance of coded FDFR multi-antenna systems with turbo-decoding: Research Articles
Authors: Renqiu Wang, Xiaoli Ma, Georgios B. Giannakis
Venue: Wireless Communications Mobile Computing (2004)

A full-diversity full-rate (FDFR) multi-antenna system was developed recently, enabling uncoded layered space-time (LST) transmissions to achieve full-diversity (Nt) and full-rate (Nt symbols per channel use) simultaneously, for any number of transmit antennas Nt and receive antennas Nr. In this paper, we investigate the performance of a coded FDFR design obtained by concatenating an error control coding (ECC) module and FDFR module with a random interleaver in between. Turbo decoding is performed at the receiver. With Rc denoting the ECC rate, dmin the minimum Hamming distance of the ECC, and M the constellation size, an overall transfer rate of RcNtlog2M bits per channel use and a full diversity order dminNtNr are achieved. Different ECC choices are considered. Approximate analysis reveals that multi-stream ECC and single-stream ECC make no difference when convolutional codes with long frame length and near-optimal MIMO decoding schemes are adopted. Without sacrificing rate, the coded FDFR system improves error performance compared with coded V-BLAST, when relatively weak codes are used. As Nr increases, even strong codes such as rate 1&#x002F;2 turbo codes can benefit from FDFR. Specifically, 1.5&ndash;2&thinsp;dB gain over coded V-BLAST is obtained in a 2&thinsp;&times;&thinsp;2 antenna setup when convolutional codes or rate 3&#x002F;4 turbo codes are used; 0.5&thinsp;dB gain is offered in a 2&thinsp;&times;&thinsp;5 setup when rate 1&#x002F;2 turbo codes are used. Coded FDFR also outperforms a 16-QAM Alamouti coded scheme by 1&thinsp;dB when convolutional codes are used. The price paid is increased complexity. Copyright &copy; 2004 John Wiley & Sons, Ltd.Part of the results in this paper was presented at IEEE International Symposium on Signal Processing and Information Technology December 14&ndash;17, 2003, Darmstadt, Germany. Guest Editor: Dr. E.G. Larsson, email: egl&commat;gwu.edu
Analyzing Relations among Software Patterns based on Document Similarity
Authors: Atsuto Kubo, Hironori Washizaki, Atsuhiro Takasu, Yoshiaki Fukazawa
Venue: Proceedings of the International Conference on Information Technology: Coding and Computing (ITCC'05) - Volume II - Volume 02 (2005)

In software development, many kinds of knowledge are shared and reused as software patterns. However, the relation analysis among software patterns by hand is difficult on the large scale. In this paper, we propose a technique for the automatic relation analysis among the patterns. Our technique is based on a new pattern model to treat various patterns, and utilizes exiting text processing techniques to extract patterns from documents and to calculate the strength of pattern relations. As a result of experiments, the system that implements our technique has extracted appropriate relations among patterns without information on relations described in original pattern documents. Moreover, our system has the ability to suggest relations among patterns that the author has not noticed.
Static analysis tools as early indicators of pre-release defect density
Authors: Nachiappan Nagappan, Thomas Ball
Venue: Proceedings of the 27th international conference on Software engineering (2005)

During software development it is helpful to obtain early estimates of the defect density of software components. Such estimates identify fault-prone areas of code requiring further testing. We present an empirical approach for the early prediction of pre-release defect density based on the defects found using static analysis tools. The defects identified by two different static analysis tools are used to fit and predict the actual pre-release defect density for Windows Server 2003. We show that there exists a strong positive correlation between the static analysis defect density and the pre-release defect density determined by testing. Further, the predicted pre-release defect density and the actual pre-release defect density are strongly correlated at a high degree of statistical significance. Discriminant analysis shows that the results of static analysis tools can be used to separate high and low quality components with an overall classification rate of 82.91%.