ppxscal/embedding_network huggingface dataset:
Autonomic management of J2EE edge servers
Authors: Mikael Desertot, Clement Escoffier, Didier Donsez
Venue: Proceedings of the 3rd international workshop on Middleware for grid computing (2005)

Nowadays, one of the biggest challenges for companies is to cope with the high cost of their information technologies infrastructure. Edge computing is a new computing paradigm designed to allocate on-demand computing and storage resources. Those resources are web cache servers scattered over the ISP backbones. We argue that this paradigm could be applied for on-demand full application hosting, helping reduce cost. In this paper, we present a J2EE dynamic server able to deploy/host J2EE applications on demand and its autonomic manager. For that, we reengineer and experiment JOnAS, an open-source J2EE static server. Two management policies of the autonomic manager were stressed by a simulation of a worldwide ISP network.
On the Economics of 3G Mobile Virtual Network Operators (MVNOs)
Authors: D. Varoutas, D. Katsianis, Th. Sphicopoulos, K. Stordahl, I. Welling
Venue: Wireless Personal Communications: An International Journal (2006)

The paper assesses the market conditions and dynamics, the architectures and the different approaches for deployment of 3G Mobile Virtual Network Operators (MVNOs), in an attempt to address specific advantages and pitfalls. Following the definition of appropriate service sets and tariff structures, and taking into account demand scenarios, a techno-economic model has been developed, in order to compute key economic indicators. The paper presents techno-economic results of specific business cases and deployment alternatives for an average "large" European country and a smaller, Nordic-type country. Fixed and variable costs have been identified and the business case shows how different service sets lead to different costs. Different MVNO business profiles have been investigated. Profitability for all scenarios and business profiles has been calculated, presented and discussed. Major opportunities and threats, as well as critical parameters and uncertainties have been identified through sensitivity analysis.
Identifying useful subgoals in reinforcement learning by local graph partitioning
Authors: Özgür Şimşek, Alicia P. Wolfe, Andrew G. Barto
Venue: Proceedings of the 22nd international conference on Machine learning (2005)

We present a new subgoal-based method for automatically creating useful skills in reinforcement learning. Our method identifies subgoals by partitioning local state transition graphs---those that are constructed using only the most recent experiences of the agent. The local scope of our subgoal discovery method allows it to successfully identify the type of subgoals we seek---states that lie between two densely-connected regions of the state space while producing an algorithm with low computational cost.
Fast Script Word Recognition with Very Large Vocabulary
Authors: Marc-Peter Schambach
Venue: Proceedings of the Eighth International Conference on Document Analysis and Recognition (2005)

For an HMM-based script word recognition system an algorithm for fast processing of large lexica is presented. It consists of two steps: First, a lexicon-free recognition is performed, followed by a tree search on the intermediate results of the first step, the trellis of probabilities. Thus, the computational effort for recognition itself can be reduced in the first step, while preserving recognition accuracy by the use of detailed information in the second step. A speedup factor of up to 15x could be obtained compared to traditional tree recognition, making script word recognition with large lexica available to time-critical tasks like in postal automation. There, lexica with e.g. all city or street names (20-500k) have to be processed within a few milliseconds.
Probabilistic, layered and hierarchical animated agents using XML
Authors: Isaac Rudomín, Erik Millán
Venue: Proceedings of the 3rd international conference on Computer graphics and interactive techniques in Australasia and South East Asia (2005)

In a previous paper we generated animated agents and their behavior in XML. These agents were specified as FSMs. We make the system more useful by implementing probabilistic FSMs. We show how more interesting behaviors can be generated. Then, we make the system more flexible and structured by implementing layered FSMs and hierarchical FSMs. We show how both of these approaches, used independently or together, allow the user to write more complex behaviors.
Analysis of multi-server systems via dimensionality reduction of markov chains
Authors: Takayuki Osogami
Venue:  (2005)

The performance analysis of multiserver systems is notoriously hard, especially when the system involves resource sharing or prioritization. We provide two new analytical tools for the performance analysis of multiserver systems: moment matching algorithms and dimensionality reduction of Markov chains (DR). Moment matching algorithms allow us to approximate a general distribution with a phase type (PH) distribution. Our moment matching algorithms improve upon existing ones with respect to the computational efficiency (we provide closed form solutions) as well as the quality and generality of the solution (the first three moments of almost any nonnegative distribution are matched). Approximating job size and interarrival time distributions by PH distributions enables modeling a multiserver system by a Markov chain, so that the performance of the system is given by analyzing the Markov chain. However, when the multiserver system involves resource sharing or prioritization, the Markov chain often has a multidimensionally infinite state space, which makes the analysis computationally hard. DR allows us to closely approximate a multidimensionally infinite Markov chain with a Markov chain on a one-dimensionally infinite state space, which can be analyzed efficiently. We validate the accuracy of DR against simulation. Further, we formally define two classes of multidimensionally infinite Markov chains, called recursive foreground-background processes and generalized foreground-background processes (RFB/GFB processes), and analyze the RFB/GFB process via DR. The definition of the RFB/GFB process enables one to easily identify whether a given multiserver system can be analyzed via DR, and our analysis of the RFB/GFB process enables the immediate analysis of a multiserver system by simply modeling it as an RFB/GFB process. These new analytical tools enable us to analyze the performance of many multiserver systems with resource sharing or prioritization for the first time. For example, we study the benefit and penalty of cycle stealing, the effectiveness of prioritization and threshold-based resource allocation policies for multiserver systems, and the impact of job size variability and irregularity of arrival processes on the response time in multiserver systems. Our analysis results in lessons on the design of good resource allocation policies for multiserver systems.
Analyzing software influences on substrate noise: an ADC perspective
Authors: F. Ghenassia, N. Vijaykrishnan, M. J. Irwin
Venue: Proceedings of the 2004 IEEE/ACM International conference on Computer-aided design (2004)

Substrate noise affects the performance of mixed signal integrated circuits. Power supply (di/dt) noise is the dominant source of substrate noise. There have been various attempts at the circuit and software levels to estimate this noise. Software-level noise estimation is especially important, as designing noise tolerant circuits for all circumstances may be prohibitively expensive. In this paper, we propose a new software approach for estimating di/dt noise and incorporate it into a power simulator in order to investigate the influence of software on substrate noise. As a case study, we investigate how an analog-to-digital converter (ADC) can be designed to adapt its resolution in the presence of substrate noise generated by a embedded processor core. The proposed strategies prevent unexpected ADC performance degradations.
The approach to compatibility of the Cambridge Project Consistent System
Venue: ACM SIGSOC Bulletin (1973)

The Cambridge Project Consistent System grew, in part, out of several of the problems of compatibility between systems and data and its design was shaped by those problems. The system recognizes, as most important, the needs of researchers to attack problems in unanticipated ways, to make novel combinations of programs with each other, and to apply programs to types of data which the program designers did not anticipate. We have also been concerned about, and have tried to anticipate, transfer of the system between computers. Viewing the system from a compatibility standpoint, it addresses: compatibility of programs so they can be operated in the same environment; compatibility of data formats, so data can be used with a variety of computational tools without need to resort to programming; and compatibility across computer systems, so the system may survive the obsolescence of a particular computer.
Exact distribution of individual displacements in linear probing hashing
Authors: Alfredo Viola
Venue: ACM Transactions on Algorithms (TALG) (2005)

This paper studies the distribution of individual displacements for the standard and the Robin Hood linear probing hashing algorithms. When the a table of size m has n elements, the distribution of the search cost of a random element is studied for both algorithms. Specifically, exact distributions for fixed m and n are found as well as when the table is &alpha;-full, and &alpha; strictly smaller than 1. Moreover, for full tables, limit laws for both algorithms are derived.
Improving Classification Decisions by Multiple Knowledge
Authors: Yaxin Bi, Sally McClean, Terry Anderson
Venue: Proceedings of the 17th IEEE International Conference on Tools with Artificial Intelligence (2005)

An important issue in data mining is how to make use of multiple discovered knowledge to improve future decisions. In this paper, we propose a new approach to combining multiple sets of rules for text categorization using Dempster's rule of combination. We develop a boosting-like technique for generating multiple sets of rules based on rough set theory and model classification decisions from multiple sets of rules as pieces of evidence which can be combined by Dempster's rule of combination. We apply these methods to 10 out of the 20-newsgroups — a benchmark data collection, individually and in combination. Our experimental results show that the performance of the best combination of the multiple sets of rules on the 10 groups of the benchmark data is statistically significantly better than that of the best single set of rules. The comparative analysis between the Demspter-Shafer and the majority voting methods along with an overfitting study confirm the advantage and the robustness of our approach.
On the usefulness of object shape coding with MPEG-4
Authors: Andrea Prati, Rita Cucchiara
Venue: Proceedings of the Seventh IEEE International Symposium on Multimedia (2005)

This paper reports the results of an in-depth analysis of the degree of usefulness of object shape coding in video compression. In particular, MPEG-4 is used as reference standard. The influence of different coding parameters on the performance is deeply examined and discussions on the results are provided. Object shape coding is compared with classical (MPEG-2) frame-based coding both at an objective level (by comparing PSNR/quality and bitrate/filesize) and at a subjective level (asking to a set of users to express their opinion on overall quality, cognitive effectiveness, and willingness to pay). In conclusion, this paper aims at answering to the question whether it is convenient to use object shape coding instead of frame-based coding or not.
Building Converged Networks with IMS Technology
Authors: David Geer
Venue: Computer (2005)

Devices and services based on the IP Multimedia Subsystem convergence approach will support a wide range of voice, data, and multimedia services over a single IP infrastructure.
Looking for Powerful Abstractions
Authors: Rebecca J. Wirfs-Brock
Venue: IEEE Software (2006)

Some claim that only innately talented designers can form good abstractions, develop a well-factored object design, or construct a domain model. The implication seems to be that design talent is rare and that only gifted designers are up to the more challenging task of creating good abstractions. Balderdash! Although design is a highly creative activity, we can still learn fundamental design skills--and accomplish a lot with them. In this column, Rebecca Wirfs-Brock explores ways of seeing that have helped her become a better designer. She starts by discussing the fundamental design skill of finding objects.
A New Way to High Performance NFS for Clusters
Authors: Rongfeng Tang, Jin Xiong, Jie Ma, Dan Meng
Venue: Proceedings of the Sixth International Conference on Parallel and Distributed Computing Applications and Technologies (2005)

For its simplicity, reliability and maturity, NFS is widely-used in clusters. However, due to its high overheads and implementation limitations, the standard NFS cannot fully exert the potential abilities provided by multiple network channels and multiple SCSI channels on the server. In this paper, we present a new efficient way to high performance NFS implementation for cluster applications. By adding mechanisms to make good use of NFS server's multiple communication channels and multiple I/O channels, CluserNFS can potentially provide better I/O performance than standard NFS, as illustrated by our simulation experiment results.
The Influence of Indirect Association Rules on Recommendation Ranking Lists
Authors: Przemyslaw Kazienko, Katarzyna Kuzminska
Venue: Proceedings of the 5th International Conference on Intelligent Systems Design and Applications (2005)

Association rules are often utilized in web recommendation systems for creation of suggested items lists. However, lists obtained in this way may be too short. Indirect association rules are introduced to extend classical, direct association rules and supplement the knowledge they contribute. The relation between ranking lists created on the basis of association rules and hyperlinks existing on web pages has also been examined in the paper.
ParaScale: Exploiting Parametric Timing Analysis for Real-Time Schedulers and Dynamic Voltage Scaling
Authors: Sibin Mohan, Frank Mueller, William Hawkins, Michael Root, Christopher Healy, David Whalley
Venue: Proceedings of the 26th IEEE International Real-Time Systems Symposium (2005)

Static timing analysis safely bounds worst-case execution times to determine if tasks can meet their deadlines in hard real-time systems. However, conventional timing analysis requires that the upper bound of loops be known statically, which limits its applicability. Parametric timing analysis methods remove this constraint by providing the WCET as a formula parameterized on loop bounds. This paper contributes a novel technique to allow parametric timing analysis to interact with dynamic real-time schedulers. By dynamically detecting actual loop bounds, a lower WCET bound can be calculated, on-the-fly, for the remaining execution of a task. We analyze the benefitsfrom parametric analysis in terms of dynamically discovered slack in a schedule. We then assess the potential for dynamic power conservation by exploiting parametric loop bounds for ParaScale, our intra-task dynamic voltage scaling (DVS) approach. Our results demonstrate that the parametric approach to timing analysis provides 66%-80% additional savings in power consumption. We further show that using this approach combined with online intra-task DVS to exploit parametric execution times results in much lower power consumption. Hence, even in the absence of dynamic scheduling, significant savings in power can be obtained, e.g., in the case of cyclic executives.
On deriving unknown vulnerabilities from zero-day polymorphic and metamorphic worm exploits
Authors: Jedidiah R. Crandall, Zhendong Su, S. Felix Wu, Frederic T. Chong
Venue: Proceedings of the 12th ACM conference on Computer and communications security (2005)

Vulnerabilities that allow worms to hijack the control flow of each host that they spread to are typically discovered months before the worm outbreak, but are also typically discovered by third party researchers. A determined attacker could discover vulnerabilities as easily and create zero-day worms for vulnerabilities unknown to network defenses. It is important for an analysis tool to be able to generalize from a new exploit observed and derive protection for the vulnerability.Many researchers have observed that certain predicates of the exploit vector must be present for the exploit to work and that therefore these predicates place a limit on the amount of polymorphism and metamorphism available to the attacker. We formalize this idea and subject it to quantitative analysis with a symbolic execution tool called DACODA. Using DACODA we provide an empirical analysis of 14 exploits (seven of them actual worms or attacks from the Internet, caught by Minos with no prior knowledge of the vulnerabilities and no false positives observed over a period of six months) for four operating systems.Evaluation of our results in the light of these two models leads us to conclude that 1) single contiguous byte string signatures are not effective for content filtering, and token-based byte string signatures composed of smaller substrings are only semantically rich enough to be effective for content filtering if the vulnerability lies in a part of a protocol that is not commonly used, and that 2) practical exploit analysis must account for multiple processes, multithreading, and kernel processing of network data necessitating a focus on primitives instead of vulnerabilities.
Specifying C++ concepts
Authors: Gabriel Dos Reis, Bjarne Stroustrup
Venue: Conference record of the 33rd ACM SIGPLAN-SIGACT symposium on Principles of programming languages (2006)

C++ templates are key to the design of current successful mainstream libraries and systems. They are the basis of programming techniques in diverse areas ranging from conventional general-purpose programming to software for safety-critical embedded systems. Current work on improving templates focuses on the notion of concepts (a type system for templates), which promises significantly improved error diagnostics and increased expressive power such as concept-based overloading and function template partial specialization. This paper presents C++ templates with an emphasis on problems related to separate compilation. We consider the problem of how to express concepts in a precise way that is simple enough to be usable by ordinary programmers. In doing so, we expose a few weakness of the current specification of the C++ standard library and suggest a far more precise and complete specification. We also present a systematic way of translating our proposed concept definitions, based on use-patterns rather than function signatures, into constraint sets that can serve as convenient basis for concept checking in a compiler.
Balancing Exploration and Exploitation: A New Algorithm for Active Machine Learning
Authors: Thomas Osugi, Deng Kun, Stephen Scott
Venue: Proceedings of the Fifth IEEE International Conference on Data Mining (2005)

Active machine learning algorithms are used when large numbers of unlabeled examples are available and getting labels for them is costly (e.g. requiring consulting a human expert). Many conventional active learning algorithms focus on refining the decision boundary, at the expense of exploring new regions that the current hypothesis misclassifies.We propose a new active learning algorithm that balances such exploration with refining of the decision boundary by dynamically adjusting the probability to explore at each step. Our experimental results demonstrate improved performance on data sets that require extensive exploration while remaining competitive on data sets that do not. Our algorithm also shows significant tolerance of noise.
Computing Cache Vulnerability to Transient Errors and Its Implication
Authors: Wei Zhang
Venue: Proceedings of the 20th IEEE International Symposium on Defect and Fault Tolerance in VLSI Systems (2005)

Transient errors caused by particle strikes have become a critical challenge for microprocessor design. Being the major consumer of on-chip real estate, cache memories are particularly susceptible to transient errors. However, not all cache soft errors can be propagated to the processor. For instance, soft errors can be corrected by write operations before they are read. In this paper, we define the cache vulnerability factor (CVF) to be the probability that a fault in the cache can be propagated to the processor or other memory hierarchy. We also propose an approach to compute the CVF based on the cache line access patterns. Building upon the CVF, we evaluate the reliability for different cache memories. Our results show that 83.5% of soft errors from a write-through data cache can be masked without affecting other components. We also propose two early write-back strategies to improve the reliability (i.e., by reducing the CVF) of write-back data caches without compromising the high performance.
Independent subspace analysis using geodesic spanning trees
Authors: Barnabás Póczos, András Lõrincz
Venue: Proceedings of the 22nd international conference on Machine learning (2005)

A novel algorithm for performing Independent Subspace Analysis, the estimation of hidden independent subspaces is introduced. This task is a generalization of Independent Component Analysis. The algorithm works by estimating the multi-dimensional differential entropy. The estimation utilizes minimal geodesic spanning trees matched to the sample points. Numerical studies include (i) illustrative examples, (ii) a generalization of the cocktail-party problem to songs played by bands, and (iii) an example on mixed independent subspaces, where subspaces have dependent sources, which are pairwise independent.
Secure collaboration in mediator-free environments
Authors: Mohamed Shehab, Elisa Bertino, Arif Ghafoor
Venue: Proceedings of the 12th ACM conference on Computer and communications security (2005)

The internet and related technologies have made multidomain collaborations a reality. Collaboration enables domains to effectively share resources; however it introduces several security and privacy challenges. Managing security in the absence of a central mediator is even more challenging. In this paper, we propose a distributed secure interoperability framework for mediator-free collaboration environments. We introduce the idea of secure access paths which enables domains to make localized access control decisions without having global view of the collaboration. We also present a path authentication technique for proving path authenticity. Furthermore, we present both a proactive and on-demand path discovery algorithms that enable domains to securely discover paths in the collaboration environment.
The use of computer simulation to develop hospital systems
Authors: Walton M. Hancock, Paul F. Walter
Venue: ACM SIGSIM Simulation Digest (1979)

The use of computer simulation in the development of hospital systems, which has a major effect on the cost and quality of operation, is presented. Discussion of results achieved in specific areas include: inpatient admissions scheduling and control systems, surgical scheduling systems, maximum average occupancy prediction models, and patient classification systems for predicting the size of nursing staffs. The paper concludes with a discussion of the general problems encountered with computer simulation.