ppxscal/embedding_network huggingface dataset:
Formal Verification for C Program
Authors: Junyan Qian_aff1n2, Baowen Xu
Venue: Informatica (2007)

Iterative abstraction refinement has emerged in the last few years as the leading approach to software model checking. We present an approach for automatically verifying C programs against safety specifications based on finite state machine. The approach eliminates unneeded variables using program slicing technique, and then automatically extracts an initial abstract model from C source code using predicate abstraction and theorem proving. In order to reduce time complexities, we partition the set of candidate predicates into subsets, and construct abstract model independently. On the basis of a counterexample-guided abstraction refinement scheme, the abstraction refines incrementally until the specification is either satisfied or refuted. Our methods can be extended to verifying concurrency C programs by parallel composition.
Detecting Hidden Hierarchy in Terrorist Networks: Some Case Studies
Authors: Nasrullah Memon, Henrik Legind Larsen, David L. Hicks, Nicholas Harkiolakis
Venue: Proceedings of the IEEE ISI 2008 PAISI, PACCF, and SOCO international workshops on Intelligence and Security Informatics (2008)

This paper provides a novel algorithm to automatically detect the hidden hierarchy in terrorist networks. The algorithm is based on centrality measures used in social network analysis literature. The advantage of such automatic methods is to detect key players in terrorist networks. We illustrate the algorithm over some case studies of terrorist events that have occurred in the past. The results show great promise in detecting high value individuals.
PORSCHE: Performance ORiented SCHEma mediation
Authors: Khalid Saleem, Zohra Bellahsene, Ela Hunt
Venue: Information Systems (2008)

Semantic matching of schemas in heterogeneous data sharing systems is time consuming and error prone. Existing mapping tools employ semi-automatic techniques for mapping two schemas at a time. In a large-scale scenario, where data sharing involves a large number of data sources, such techniques are not suitable. We present a new robust automatic method which discovers semantic schema matches in a large set of XML schemas, incrementally creates an integrated schema encompassing all schema trees, and defines mappings from the contributing schemas to the integrated schema. Our method, PORSCHE (Performance ORiented SCHEma mediation), utilises a holistic approach which first clusters the nodes based on linguistic label similarity. Then it applies a tree mining technique using node ranks calculated during depth-first traversal. This minimises the target node search space and improves performance, which makes the technique suitable for large-scale data sharing. The PORSCHE framework is hybrid in nature and flexible enough to incorporate more matching techniques or algorithms. We report on experiments with up to 80 schemas containing 83,770 nodes, with our prototype implementation taking 587s on average to match and merge them, resulting in an integrated schema and returning mappings from all input schemas to the integrated schema. The quality of matching in PORSCHE is shown using precision, recall and F-measure on randomly selected pairs of schemas from the same domain. We also discuss the integrity of the mediated schema in the light of completeness and minimality measures.
RG-EDF: An I/O Scheduling Policy for Flash Equipped Sensor Devices
Authors: Adam Ji Dou, Vana Kalogeraki
Venue: Proceedings of the 6th IFIP WG 10.2 international workshop on Software Technologies for Embedded and Ubiquitous Systems (2008)

Flash equipped sensor devices are becoming increasingly complex and are now capable of supporting real-time multiple applications on a single sensor, rich sensing of visual and audio data, and storage of large amounts of data. With this increase in complexity, it is no longer sufficient to provide first in first out (FIFO) type capture of data into more persistent memories. In this paper we propose RG-EDF, a new scheduling policy for flash equipped sensor devices. RG-EDF aims at providing QoS support to multimedia tasks by considering the unique characteristics of flash-based devices. We have implemented our scheme on a CC1010 sensor node with a SD flash card attached and compared our technique to other popular scheduling policies. Our experimental results show the working and benefit of our system.
Effective static race detection for java
Authors: Alex Aiken
Venue:  (2008)

Concurrent programs are notoriously difficult to write and debug, a problem that is becoming acute with the recent shift in hardware from uniprocessors to multicore processors. A fundamental concurrency bug is a race: a condition in a shared-memory multithreaded program in which a pair of threads may access the same memory location without any ordering enforced between the accesses, and at least one of the accesses is a write. Despite thirty years of research on race detection, today's concurrent programs are still riddled with harmful races.We present an effective approach to static race detection for Java. We dissect the specification of a race to identify four natural conditions, each of which is sufficient for proving a given pair of accesses race-free, and all of which are necessary in practice as different pairs of accesses may be race-free for different reasons. We present four static analyses each of which conservatively approximates a separate condition while together enabling the overall algorithm to report a useful set of potential races. We have implemented our approach and report upon our experience applying it to a suite of eight multithreaded Java programs which includes a mix of libraries, complete programs, previously studied programs, and newer, real-world, open-source programs. For complete programs, the approach is sound in that it finds all races. On our benchmark suite, the approach is precise in that it has a false positive rate of 25% (only one in every four reported races is not in fact a race) and it is reasonably scalable in that it is fully automatic and checks programs comprising hundreds of thousands of Java bytecodes in a few minutes. Finally, the approach is effective, finding tens to hundreds of previously unknown concurrency bugs in mature and widely used Java programs in our benchmark suite, many of which were fixed upon reporting.
Discovering Documentation for Java Container Classes
Authors: Johannes Henkel, Christoph Reichenbach, Amer Diwan
Venue: IEEE Transactions on Software Engineering (2007)

Modern programs make extensive use of reusable software libraries. For example, we found that 17% to 30% of the classes in a number of large Java applications use the container classes from the java.util package. Given this extensive code reuse in Java programs, it is important for the reusable interfaces to have clear and unambiguous documentation. Unfortunately, most documentation is expressed in English, and therefore does not always satisfy these requirements. Worse yet, there is no way of checking that the documentation is consistent with the associated code. Formal specifications present an alternative which does not suffer from these problems; however, formal specifications are notoriously hard to write. To alleviate this difficulty, we have implemented a tool which automatically derives documentation in the form of formal specifications. Our tool probes Java classes by invoking them on dynamically generated tests and captures the information observed during their execution as algebraic axioms. While the tool is not complete or correct from a formal perspective we demonstrate that it discovers many useful axioms when applied to container classes. These axioms then form an initial formal documentation of the class they describe.
Mining Evolving Web Sessions and Clustering Dynamic Web Documents for Similarity-Aware Web Content Management
Authors: Jitian Xiao
Venue: Proceedings of the 4th international conference on Advanced Data Mining and Applications (2008)

Similarity discovery has become one of the most important research streams in web usage mining community in the recent years. The knowledge obtained from the exercise can be used for many applications such as predicting user's preference, optimizing web cache organization and improving the quality of web document pre-fetching. This paper presents an approach of mining evolving web sessions to cluster web users and establish similarities among web documents, which are then applied to a Similarity-aware Web content Management system, facilitating offline building of the similarity-ware web caches and online updating of sub-caches and cache content similarity profiles. An agent-based web document pre-fetching mechanism is also developed to support the similarity-aware caching to further reduce the bandwidth consumption and network traffic latency, therefore to improve the web access performance.
Strategies for Consistent Image Partitioning
Authors: David J. Kasik
Venue: IEEE MultiMedia (2004)

Graphic display technologies have traditionally targeted devices with midsize screens. However, devices with small and large screen sizes are gaining popularity, with users increasingly attempting to access complex images using small-screen devices. To display high-quality images irrespective of screen size, new methods of visualization become necessary.
Operating System for the B 5000
Authors: Clark Oliphint
Venue: IEEE Annals of the History of Computing (1987)

An overview of the design objectives and implementation of the B 5000 OS.
What's new?: making web page updates accessible
Authors: Yevgen Borodin, Jeffrey P. Bigham, Rohit Raman, I. V. Ramakrishnan
Venue: Proceedings of the 10th international ACM SIGACCESS conference on Computers and accessibility (2008)

Web applications facilitated by technologies such as JavaScript, DHTML, AJAX, and Flash use a considerable amount of dynamic web content that is either inaccessible or unusable by blind people. Server side changes to web content cause whole page refreshes, but only small sections of the page update, causing blind web users to search linearly through the page to find new content. The connecting theme is the need to quickly and unobtrusively identify the segments of a web page that have changed and notify the user of them. In this paper we propose Dynamo, a system designed to unify different types of dynamic content and make dynamic content accessible to blind web users. Dynamo treats web page updates uniformly and its methods encompass both web updates enabled through dynamic content and scripting, and updates resulting from static page refreshes, form submissions, and template-based web sites. From an algorithmic and interaction perspective Dynamo detects underlying changes and provides users with a single and intuitive interface for reviewing the changes that have occurred. We report on the quantitative and qualitative results of an evaluation conducted with blind users. These results suggest that Dynamo makes access to dynamic content faster, and that blind web users like it better than existing interfaces.
Extensive Epidemic Spreading Model Based on Multi-agent System Framework
Authors: Chunhua Tian, Wei Ding, Rongzeng Cao, Shun Jiang
Venue: Proceedings of the 7th international conference on Computational Science, Part IV: ICCS 2007 (2007)

In current epidemic spreading study, continuous system dynamics model and discrete agent model are often regarded as two types of incompatible models. However these two types of models may coexist in large-scale epidemic simulation. A multi-agent based framework for such coexisting is proposed in this paper consisting of location agents with hierarchical structure, participant agents to denote host, pathogen, or medium, and event agent to model the epidemic outbreak, control policy, etc. Transformation algorithm is provided for the communication between locations with different types of epidemic models. Such a framework is illustrated by SARS (Severe Acute Respiratory Syndrome) outbreak case.
Prediction Horizons in Agent Models
Authors: H. Dyke Parunak, Theodore C. Belding, Sven A. Brueckner
Venue: Engineering Environment-Mediated Multi-Agent Systems: International Workshop, EEMMAS 2007, Dresden, Germany, October 5, 2007. Selected Revised and Invited Papers (2008)

One motivation for many agent-based models is to predict the future. The nonlinearity of agent interactions in most non-trivial domains mean that the usefulness of such predictions will be limited beyond a certain point (the "prediction horizon"), due to unbounded divergence of their trajectories. The model's predictions are increasingly useful out to the prediction horizon, but become misleading beyond that point. We exhibit and characterize this behavior in a simple model, based on the polyagent modeling construct, which uses multiple ghost agents mediated through a shared environment to explore alternative futures concurrently for a domain entity. We also discuss how a single agent in such a model can estimate the prediction horizon based on locally available information, and use this estimate to modulate dynamically how far it seeks to look into the future.
Multilevel methodology for simulation of spatio-temporal systems with heterogeneous activity: application to spread of valley fever fungus
Authors: Bernard P. Zeigler
Venue:  (2008)

Spatio-temporal systems with heterogeneity in their structure and behavior have two major problems. The first one is that such systems extend over very large spatial and temporal domains and consume a lot of resources to simulate that they are infeasible to study with current platforms. The second one is that the data available for understanding such systems is limited. This also makes it difficult to get the data for validation of their constituent processes while simultaneously considering their global behavior. For example, the valley fever fungus considered in this dissertation is spread over a large spatial grid in the arid Southwest and typically needs to be simulated over several decades of time to obtain useful information. It is also hard to get the temperature and moisture data at every grid point of the spatial domain over the region of study. In order to address the first problem, we develop a method based on the discrete event system specification which exploits the heterogeneity in the activity of the spatio-temporal system and which has been shown to be effective in solving relatively simple partial differential equation systems. The benefit of addressing the first problem is that it now makes it feasible to address the second problem. We address the second problem by making use of a multilevel methodology based on modeling and simulation and systems theory. This methodology helps us in the construction of models with different resolutions (base and lumped models). This allows us to refine an initially constructed lumped model with detailed physics-based process models and assess whether they improve on the original lumped models. For that assessment, we use the concept of experimental frame to delimit where the improvement is needed. This allows us to work with the available data, improve the component models in their own experimental frame and then move them to the overall frame. In this dissertation, we develop a multilevel methodology and apply it to a valley fever model. Moreover, we study the model's behavior in a particular experimental frame of interest, namely the formation of new sporing sites.
Large-Scale Parallel Collaborative Filtering for the Netflix Prize
Authors: Yunhong Zhou, Dennis Wilkinson, Robert Schreiber, Rong Pan
Venue: Proceedings of the 4th international conference on Algorithmic Aspects in Information and Management (2008)

Many recommendation systems suggest items to users by utilizing the techniques of collaborative filtering (CF) based on historical records of items that the users have viewed, purchased, or rated. Two major problems that most CF approaches have to contend with are scalability and sparseness of the user profiles. To tackle these issues, in this paper, we describe a CF algorithm alternating-least-squares with weighted-¿ -regularization (ALS-WR), which is implemented on a parallel Matlab platform. We show empirically that the performance of ALS-WR (in terms of root mean squared error (RMSE)) monotonically improves with both the number of features and the number of ALS iterations. We applied the ALS-WR algorithm on a large-scale CF problem, the Netflix Challenge, with 1000 hidden features and obtained a RMSE score of 0.8985, which is one of the best results based on a pure method. In addition, combining with the parallel version of other known methods, we achieved a performance improvement of 5.91% over Netflix's own CineMatch recommendation system. Our method is simple and scales well to very large datasets.
Another Dimension of Web-Based Learning: Psychological Bestirring
Authors: Zhiwen Wang
Venue: Proceedings of the 7th international conference on Advances in Web Based Learning (2008)

The concepts of psychological bestirring and psychological distance in web-based learning situation are proposed. Their significance and effects are examined. An online learning performance model is constructed which employs psychological bestirring as a new factor independent of the factor of information stimulation. Logistic equation and curve is suggested as its fundamental mathematic model. The model was then used to explain the restriction of psychological distance on the usually overestimated advantages of distance education, especially the massive scale and the asynchronous learning opportunity. It is also argued for that the web-based learning framework provides the highest potential to enhance psychological bestirring among different forms of non-face-to-face learning, because of its close integration with BBS, chat room, email, instant messaging, blog and other growing internet-based interactions. Some suggestions drawn out of practice are also presented to make better use of psychological bestirring in web-based learning situation.
Industrial Use of Formal Methods for a High-Level Security Evaluation
Authors: Boutheina Chetali, Quang-Huy Nguyen
Venue: Proceedings of the 15th international symposium on Formal Methods (2008)

This paper presents an effective use of formal methods for the development and for the security certification of smart card software. The approach is based on the Common Criteria's methodology that requires the use of formal methods to prove that a product implements the claimed security level. This work led to the world-first certification of a commercial Java Card TM product involving all formal assurances needed to reach the highest security level. For this certification, formal methods have been used for the design and the implementation of the security functions of the Java Card system embedded in the product. We describe the refinement scheme used to meet the Common Criteria's requirements on formal models and proofs. In particular, we show how to build the proof that the implementation ensures the security objectives claimed in the security specification. We also provide some lessons learned from this important application of formal methods to the smart cards industry.
An Adaptive Cartography of DTV Programs
Authors: Jean-Gabriel Ganascia, Charles Madeira, Karan Fouladi
Venue: Proceedings of the 6th European conference on Changing Television Environments (2008)

With the development of information technologies and more precisely, the so-called digital convergence, the number of digital TV (DTV) programs available on any kind of DTV receiver (satellite, cable, terrestrial or IP) has increased dramatically. This has made the task of selecting a DTV program very complicated and time consuming. This paper proposes an intelligent graphical user interface (GUI) tool that gives a new appearance to the on-air and recorded DTV contents in order to enable DTV viewers to, quickly and in a user-friendly manner, select a program. The GUI tool is based on a synthetic cartography of DTV programs in which the shape generated reflects the DTV viewers' preferences over a period of time. These preferences are obtained by using any method for program clustering and recommendation. Results are demonstrated on the task of recommending programs in the context of the French terrestrial DTV by using a content-based approach.
Real-Time Communications on an Integrated Fieldbus Network Based on a Switched Ethernet in Industrial Environment
Authors: Dao Manh Cuong, Myung Kyun Kim
Venue: Proceedings of the 3rd international conference on Embedded Software and Systems (2007)

In recent years, fieldbuses have been more widely used in real-time distributed control systems. There are many international fieldbus protocol standards, but they are not interoperable among themselves. This paper proposes an integrated fieldbus network architecture based on a switched Ethernet which provides real-time communication features to the nodes in different fieldbuses. This paper also analyzes the schedulability conditions for real-time periodic messages on the switched Ethernet and an EDF (Earliest Deadline First)-based scheduling algorithm to support the real-time communication requirements of the periodic messages without any change in the principles of the switch.
Application Study in Decision Support with Fuzzy Cognitive Map
Authors: Yue He
Venue: Proceedings of the 12th international conference on Knowledge-Based Intelligent Information and Engineering Systems, Part II (2008)

Fuzzy cognitive map is an approach to knowledge representation and inference. Little research has been done on the goal-oriented analysis with FCM. We propose a methodology based on the use of Fuzzy cognitive map and immune algorithm to find the initial state of system from among a large number of possible states. Finally, an illustrative example is provided, and its results suggest that the method is capable of goal-oriented decision support.
Using Sense Recognition to Resolve the Problem of Polysemy in Building a Taxonomic Hierarchy
Authors: Lei Liu, Sen Zhang, Lu Hong Diao, Shu Ying Yan, Cun Gen Cao
Venue: Proceedings of the 12th international conference on Knowledge-Based Intelligent Information and Engineering Systems, Part I (2008)

Hyponymy is used to build a taxonomic hierarchy. But the terms in hyponymy may have multiple senses. It will cause the problem of polysemy and affect the building of taxonomic hierarchy. In order to solve the problem, we present a method of sense recognition of hyponymy based on vector space model. Firstly we acquire the contexts of hyponymy from Chinese free corpus. Secondly we use Cilin to construct a relation-word vector space. Then we use latent semantic analysis to reduce the dimension of the vector space. In the final phase, we recognize the senses of hyponymy using average-group clustering. Experimental results show that the method can provide adequate discrimination of the different senses.
Teaching agile validation of data models
Authors: Vladan Jovanovic, Lily Cupic
Venue: Proceedings of the 9th ACM SIGITE conference on Information technology education (2008)

The paper presents a novel approach to teaching agile validation of data models. The advantage of this approach is in minimizing required classroom time to achieve desirable learning outcomes of understanding model validation and of enabling ability to perform such validations. The primary contribution of the paper is in formulating the first agile approach to data model validation suitable for students. The paper explains agile methods proposed to be used together, compares agile with traditional reviews and provides suggestions for teaching agile validation of data models across computing disciplines.