ppxscal/embedding_network huggingface dataset:
Do social networks improve e-commerce?: a study on social marketplaces
Authors: Gayatri Swamynathan, Christo Wilson, Bryce Boe, Kevin Almeroth, Ben Y. Zhao
Venue: Proceedings of the first workshop on Online social networks (2008)

Social networks have made a significant impact on how Internet users communicate, search for and share data today. Numerous proposals have been made to improve existing distributed systems by leveraging the inherent trust built into social links. For example, many believe that by augmenting online marketplaces with social networking, we can improve trust between transaction partners and increase user satisfaction. In this paper, we perform a detailed study of Overstock Auctions, an auction site that has recently integrated social links into user profiles. Using data on connections between roughly 400,000 Overstock users, we evaluate the impact of social connections on business transactions. Our results show that while the majority of users do not engage in social networking, those who transact with friends from their social network generally obtain significant benefits in the form of higher user satisfaction.
The role of the dikw hierarchy in the design of a digital library system for the scientific data of large-scale evaluation campaigns
Authors: Marco Dussin, Nicola Ferro
Venue: Proceedings of the 8th ACM/IEEE-CS joint conference on Digital libraries (2008)

This paper exploit the DIKW hierarchy as a framework for modelling the scientific data produced during large-scale evaluation campaigns for information retrieval systems in order to design a digital library system able to manage and support the course of such evaluation campaigns.
Microfluidic devices for optical determination of ethanol concentration
Authors: L. Lei, I. L. Mattos, Y. Chen
Venue: Microelectronic Engineering (2008)

A microfluidic device with integrated optical fibres has been used for the determination of the ethanol concentration in wines and beverages. Two cleaved optical fibres were placed face to face perpendicularly to the microfluidic channel with a gap comparable to the width of the channel. They are respectively connected to a light source and a spectrometer for the optical detection. Absorption spectra of a mixture of potassium dichromate plus sulphuric acid and diluted ethanol have been studied as a function of ethanol content, showing a linear dependence between the measured absorbance and the ethanol concentration. Then, several commercial potable spirits and wines have been used to demonstrate the applicability of the proposal microfluidic method.
A subexponential algorithm for abstract optimization problems
Authors: B. Gartner
Venue: Proceedings of the 33rd Annual Symposium on Foundations of Computer Science (1992)

An abstract optimization problem (AOP) is a triple (H,
An Adaptive Index of XML for Frequent Branching Path Queries
Authors: Yingjie Fan, Chenghong Zhang, Shuyun Wang, Xiulan Hao, Yunfa Hu
Venue: Proceedings of the Seventh IEEE/ACIS International Conference on Computer and Information Science (icis 2008) (2008)

Structural index, which acts as a structural summary, plays an important role in query optimization over XML and semi-structured data. To speed up branching path queries, we introduce the notion of k-l-bisimilarity into M(k)-index and propose an adaptive structural index, MBF(k, l)-index, which supports branching paths with any complexity efficiently and inherits the advantage of avoiding over-refinement from M(k)-index. Our experiments have shown that the index performs more efficiently in terms of space consumption and query performance for branching or simple paths in comparison with the same kind of indexes.
Making a case for situation-dependent user profiles in context-aware environments
Authors: Michael Sutterer, Olaf Droegehorn, Klaus David
Venue: Proceedings of the 2007 Workshop on Middleware for next-generation converged networks and applications (2007)

Next-generation network applications aim at personalizing their services regarding the user's situation. This process calls for an adequate management of situation-dependent user preferences. We present arguments making clear the benefits of structuring a user profile into situation-dependent sub-profiles, especially for context-aware systems that comprise a huge agglomeration of situation-dependent user preferences. Whereas we only shortly address this approach from a human factors research perspective, we provide a detailed analytic evaluation why situation-dependent sub-profiles are superior to currently available user profile structuring approaches from a technical perspective. In particular, we show that runtime performance for searching matching situation-dependent user preferences after a situation change is superior, in case user preferences are clustered into situation-dependent sub-profiles.
Exploiting environmental properties for wireless localization
Authors: Shu Chen, Yingying Chen, Wade Trappe
Venue: ACM SIGMOBILE Mobile Computing and Communications Review (2008)

Wireless sensor networks are usually deployed to monitor environmental fields. In this work, we take a different viewpoint by dual-using the wireless sensor networks beyond their original purpose and exploit the general spatial information fields associated with wireless networks to assist position verification and refine conventional localization results. We developed the Flex - EP algorithm. And further our experimental evaluation results provide strong evidence that our approach can achieve the similar performance as traditional localization algorithms, without requiring the deployment of a localization infrastructure.
A field study of the requirements engineering practice in Australian software industry
Authors: Emila Sadraei, Ayb&#x00fc;ke Aurum, Ghassan Beydoun, Barbara Paech
Venue: Requirements Engineering (2007)

Empirical studies have demonstrated that requirements errors introduced during software development are most numerous in the software life-cycle, making software requirements critical determinants of software quality. This article reports an exploratory study which provides insight into industrial practices with respect to requirements engineering (RE). A combination of both qualitative and quantitative data is collected, using semi-structured interviews and a detailed questionnaire from 28 software projects in 16 Australian companies. The contribution of this RE study is threefold: Firstly, it includes a detailed examination of the characteristics of the RE activities involved in the projects. Secondly, it reconstructs the underlying practiced process models. Thirdly, it compares these models to one another and with a number of well-known process models from RE literature to give insight into the gap between RE theory and practice.
Accurate memory signatures and synthetic address traces for HPC applications
Authors: Jonathan Weinberg, Allan Edward Snavely
Venue: Proceedings of the 22nd annual international conference on Supercomputing (2008)

Though the performance of many scientific codes is dominated by memory behavior, our ability to describe, capture, compare, and recreate that behavior is quite limited. This inability underlies much of the complexity in the field of performance analysis: it is fundamentally difficult to relate benchmarks and applications or use realistic workloads to guide system design and procurement. An observable, reproducible, and machine-independent memory characterization is needed. The Chameleon framework is a software suite that includes tools to capture a concise, machine-independent memory signature from any application and produce synthetic memory address traces that mimic that signature. By simultaneously modeling both spatial and temporal locality, Chameleon produces uniquely accurate, general-purpose synthetic traces. Our results demonstrate that the cache hit rates generated by each synthetic trace are nearly identical to those of the application it targets on dozens of memory hierarchies representing many of today's commercial offerings. We apply the framework to high-performance computing (HPC) by leveraging sampling techniques to capture the memory signatures of full-scale, parallel applications with only a 5x slowdown. The overall result is therefore a concise, observable, and machine-independent representation of the memory requirements of full-scale applications that can be tractably captured and accurately mimicked.
BorderPatrol: isolating events for black-box tracing
Authors: Eric Koskinen, John Jannotti
Venue: Proceedings of the 3rd ACM SIGOPS/EuroSys European Conference on Computer Systems 2008 (2008)

Causal request traces are valuable to developers of large concurrent and distributed applications, yet difficult to obtain. Traces show how a request is processed, and can be analyzed by tools to detect performance or correctness errors and anomalous behavior. We present BorderPatrol, which obtains precise request traces through suystems built from a litany of unmodified modules. Traced components include Apache, thttpd, PostgreSQL, TurboGears, BIND and notably Zeus, a closed-source event-driven web server. BorderPatrol obtains traces using active observation which carefully modifies the event stream observed by modules, simplifying precise observation. Protocol processors leverage knowledge about standard protocols, avoiding application-specific instrumentation. BorderPatrol obtains precise traces for black-box systems that cannot be traced by any other technique. We confirm the accuracy of BorderPatrol's traces by comparing to manual instrumentation, and compare the developer effort required for each kind of trace. BorderPatrol imposes limited overhead on real systems (approximately 10-15%) and it may be enabled or disabled in at run-time, making it a viable option for deployment in production environments.
I2MeDS: Intelligent Integrated Medical Data System
Authors: Jason Uher, Dillon Sadofsky, Jong-Hoon Youn, Hesham Ali, Hamid Sharif, Jitender Deogun, Steven H. Hinrichs
Venue: Proceedings of the 2008 International Conference on BioMedical Engineering and Informatics - Volume 01 (2008)

Miniaturization of computing devices and advances in wireless communication have fueled interest in the development of new and innovative applications in many fields, including medical diagnosis, environmental monitoring, and industrial applications. Although medical instruments have benefited a great deal from the technological advances in past decades, many practices and day-to-day activities in medical environments remain virtually unchanged. Due to concerns about security and reliability of new technologies, penetration of IT advancements into the medical domain remains a challenge. This paper shows how healthcare can benefit significantly from incorporating various IT developments, particularly wireless technologies. Proposed here is a new model for utilizing wireless technology to address key issues in medical environments, such as monitoring and tracking medical assets and detecting/preventing errors during medication administration. The proposed Intelligent Integrated Medical Data System (I2MeDS) is based on the development of a secure and reliable network infrastructure with a unified database management system.
Mixed hierarchical-functional fault models for targeting sequential cores
Authors: Jaan Raik, Raimund Ubar, Taavi Viilukas, Maksim Jenihhin
Venue: Journal of Systems Architecture: the EUROMICRO Journal (2008)

Current work presents a set of fault models allowing high coverage for sequential cores in systems-on-a-chip. We propose a novel approach combining a hierarchical fault model for functional blocks, a functional fault model for multiplexers and a mixed hierarchical-functional fault model for comparison operators, respectively. The fault models are integrated into a fast high-level decision diagram based test path activation tool. According to the experiments, the proposed method significantly outperforms state-of-the-art test pattern generation tools. The main new contribution of this paper is a formal definition of high-level decision diagram representations and the combination of the three fault models in order to target high gate-level stuck-at fault coverage for sequential cores.
Scheduling scientific workflow applications with deadline and budget constraints using genetic algorithms
Authors: Jia Yu, Rajkumar Buyya
Venue: Scientific Programming (2006)

Grid technologies have progressed towards a service-oriented paradigm that enables a new way of service provisioning based on utility computing models, which are capable of supporting diverse computing services. It facilitates scientific applications to take advantage of computing resources distributed world wide to enhance the capability and performance. Many scientific applications in areas such as bioinformatics and astronomy require workflow processing in which tasks are executed based on their control or data dependencies. Scheduling such interdependent tasks on utility Grid environments need to consider users' QoS requirements. In this paper, we present a genetic algorithm approach to address scheduling optimization problems in workflow applications, based on two QoS constraints, deadline and budget.
Employ a mobile agent for making a payment
Authors: Yan Wang, Duncan S. Wong, Huaxiong Wang
Venue: Mobile Information Systems (2008)

The mobile agent paradigm offers flexibility and autonomy to e-commerce applications. But it is challenging to employ a mobile agent to make a payment due to the security consideration. In this paper, we propose a new agent-assisted secure payment protocol, which is based on SET payment protocol and aims at enabling the dispatched consumer-agent to autonomously sign contracts and make the payment on behalf of the cardholder after having found the best merchant, without the possibility of disclosing any secret to any participant. This is realized by adopting the Signature-Share scheme, and employing a Trusted Third Party (TTP). In the proposed protocol, the principle that each participant knows what is strictly necessary for his/her role is followed as in SET. In addition, mechanisms have been devised for preventing and detecting double payment, overspending and overpayment attacks. Finally the security properties of the proposed protocol are studied analytically. In comparison with other existing models, the proposed protocol is more efficient and can detect more attacks.
Canonicalization of graph database records using similarity measures
Authors: Na Li, Qing Li, Liping Wang
Venue: Proceedings of the 2nd international conference on Ubiquitous information management and communication (2008)

Information extraction and crawling from the Web have been increasingly common, yet raw data are often noisy and redundant due to heterogeneous sources. Although much work has focused on duplicate records detection, there is little investigation in providing a uniform, standard result from the duplicates to users, which we refer to as a canonical result, and the process is referred to record canonicalization. In this paper, we focus on the situation of imperfect and duplicate documents on the Web, and propose a preprocessing method of graph canonicalization. We first formalize the problem of graph records canonicalization, and then we propose three possible solutions in order. Upon the framework, we implement graph selection canonicalization, which aims to construct a canonical graph by selecting the central graph among records. Experiment results demonstrate its performance in representing real world entities.
Fast solvers and efficient implementations for distance metric learning
Authors: Kilian Q. Weinberger, Lawrence K. Saul
Venue: Proceedings of the 25th international conference on Machine learning (2008)

In this paper we study how to improve nearest neighbor classification by learning a Mahalanobis distance metric. We build on a recently proposed framework for distance metric learning known as large margin nearest neighbor (LMNN) classification. Our paper makes three contributions. First, we describe a highly efficient solver for the particular instance of semidefinite programming that arises in LMNN classification; our solver can handle problems with billions of large margin constraints in a few hours. Second, we show how to reduce both training and testing times using metric ball trees; the speedups from ball trees are further magnified by learning low dimensional representations of the input space. Third, we show how to learn different Mahalanobis distance metrics in different parts of the input space. For large data sets, the use of locally adaptive distance metrics leads to even lower error rates.
Sliding modes time varying matrix identification for stochastic system
Authors: A. Poznyak, J. Escobar, Y. Shtessel
Venue: International Journal of Systems Science (2007)

Time varying parameters identification of stochastic systems is addressed via sliding mode parameter observers. Sliding mode observer is governed by control that compensates a so-called Ito's term, which reflects a stochastic nature of a system. The matrix estimation algorithm based on equivalent control is proposed. A numerical example illustrates the effectiveness of the proposed approach.
End spaces of graphs are normal
Authors: Philipp Sprüssel
Venue: Journal of Combinatorial Theory Series B (2008)

We show that the topological space of any infinite graph and its ends is normal. In particular, end spaces themselves are normal.
Developing a Novel Framework for Effective Use of Implicit Feedback in Adaptive e-Learning
Authors: Ahmad Kardan, Hamed Monkaresi
Venue: Proceedings of the Fifth International Conference on Information Technology: New Generations (2008)

Adaptation and personalization in an e-learning process has a major effect on the relation between tutorial content selection and user learning level. Implicit feedbacks, which are easy to collect and have no effect on learning process, are introduced as valuable resources in many different adaptation methods. Common adaptive learning systems are short of an integrated and standard method for incorporating parameters like time spent for reading (TSR), page clicks, and page scrolling time. Recent methods and reports in this area are topic specific and usually not related to learning paradigms. In order to address this problem, we introduce a general framework for defining a relation between a combination of user implicit feedback and its learning level. This relation is trained as a component by some real data in a way that it could be reused in a learning management system.
The complexity of the covering radius problem
Authors: Venkatesan Guruswami, Daniele Micciancio, Oded Regev
Venue: Computational Complexity (2005)

We initiate the study of the computational complexity of the covering radius problem for lattices, and approximation versions of the problem for both lattices and linear codes. We also investigate the computational complexity of the shortest linearly independent vectors problem, and its relation to the covering radius problem for lattices. For the covering radius on n-dimensional lattices, we show that the problem can be approximated within any constant factor ¿(n) > 1 in random exponential time 2 O(n). We also prove that suitably defined gap versions of the problem lie in AM for ¿(n) = 2, in coAM for $$ \gamma (n) = {\sqrt {n/\log n} }, $$ and in NP ¿ coNP for $$ \gamma (n) = {\sqrt n }. $$ For the covering radius on n-dimensional linear codes, we show that the problem can be solved in deterministic polynomial time for approximation factor $$ \gamma (n) = \log n, $$ but cannot be solved in polynomial time for some $$ \gamma (n) = \Omega (\log \log n) $$ unless NP can be simulated in deterministic $$ n^{{O(\log \log \log n)}} $$ time. Moreover, we prove that the problem is NP-hard for any constant approximation factor, it is ¿2-hard for some constant approximation factor, and that it is unlikely to be ¿2-hard for approximation factors larger than 2 (by giving an AM protocol for the appropriate gap problem). This is a natural hardness of approximation result in the polynomial hierarchy.For the shortest independent vectors problem, we give a coAM protocol achieving approximation factor $$ \gamma (n) = {\sqrt {n/\log n} }, $$ solving an open problem of Blömer and Seifert (STOC'99), and prove that the problem is also in coNP for $$ \gamma (n) = {\sqrt n }. $$ Both results are obtained by giving a gap-preserving nondeterministic polynomial time reduction to the closest vector problem.
Triangle-free graphs that are signable without even holes
Authors: Michele Conforti, Gérard Cornuéjols, Ajai Kapoor, Kristina Vušković
Venue: Journal of Graph Theory (2000)

We characterize triangle-free graphs for which there exists a subset of edges that intersects every chordless cycle in an odd number of edges (TF odd-signable graphs). These graphs arise as building blocks of a decomposition theorem (for cap-free odd-signable graphs) obtained by the same authors. We give a polytime algorithm to test membership in this class. This algorithm is itself based on a decomposition theorem. &copy; 2000 John Wiley & Sons, Inc. J Graph Theory 34: 204&ndash;220, 2000
Computational complexity of weighted splitting schemes on parallel computers
Authors: P. Csomós, I. Dimov, I. Faragó, Á. Havasi, T. Z. Ostromsky
Venue: International Journal of Parallel, Emergent and Distributed Systems (2007)

In models of complicated physical-chemical processes operator splitting is very often applied in order to achieve sufficient accuracy as well as efficiency of the numerical solution. The recently rediscovered weighted splitting schemes have the great advantage of being parallelizable on operator level, which allows us to reduce the computational time if parallel computers are used. In this paper, the computational times needed for the weighted splitting methods are studied in comparison with the sequential (S) splitting and the Marchuk-Strang (MSt) splitting and are illustrated by numerical experiments performed by use of simplified versions of the Danish Eulerian model (DEM).
CSV: visualizing and mining cohesive subgraphs
Authors: Nan Wang, Srinivasan Parthasarathy, Kian-Lee Tan, Anthony K. H. Tung
Venue: Proceedings of the 2008 ACM SIGMOD international conference on Management of data (2008)

Extracting dense sub-components from graphs efficiently is an important objective in a wide range of application domains ranging from social network analysis to biological network analysis, from the World Wide Web to stock market analysis. Motivated by this need recently we have seen several new algorithms to tackle this problem based on the (frequent) pattern mining paradigm. A limitation of most of these methods is that they are highly sensitive to parameter settings, rely on exhaustive enumeration with exponential time complexity, and often fail to help the users understand the underlying distribution of components embedded within the host graph. In this article we propose an approximate algorithm, to mine and visualize cohesive subgraphs (dense sub components) within a large graph. The approach, refereed to as Cohesive Subgraph Visualization (CSV) relies on a novel mapping strategy that maps edges and nodes to a multi-dimensional space wherein dense areas in the mapped space correspond to cohesive subgraphs. The algorithm then walks through the dense regions in the mapped space to output a visual plot that effectively captures the overall dense sub-component distribution of the graph. Unlike extant algorithms with exponential complexity, CSV has a complexity of O(V2logV) when fixing the parameter mapping dimension, where V corresponds to the number of vertices in the graph, although for many real datasets the performance is typically sub-quadratic. We demonstrate the utility of CSV as a stand-alone tool for visual graph exploration and as a pre-filtering step to significantly scale up exact subgraph mining algorithms such as CLAN.