ppxscal/embedding_network huggingface dataset:
Treemap visualizations for CS2
Authors: Martha J. Kosa, Mark A. Boshart
Venue: Proceedings of the 9th annual SIGCSE conference on Innovation and technology in computer science education (2004)

Computer science instructors periodically need to update their classroom examples and programming assignments in order to reflect changes in current practice in the field and to discourage copying by students. As experienced CS2 instructors, we regularly face this challenge. The topics in our CS2 course are standard and include recursion, lists, stacks, queues, and trees (including B-trees as well as standard binary search trees and AVL trees). Our students use Java (including GUIs). We have experimented with having students use and write programs to visualize various data structures. The students have written programs to visualize search trees using the traditional approach in which ovals represent nodes and lines represent links. They have also written programs to visualize search trees via a Web browser [2]. We propose an alternate visualization technique based on treemaps. We believe that treemaps are a rich source for classroom examples and assignments for CS2 instructors. Trees are useful for storing hierarchical data, and they are naturally recursive. A tree is either empty, or it has a root node with subtrees. A root is connected to its subtrees by links or branches. We had an idea to draw a tree in a square, which would be split into multiple rectangles, one for each node in the tree. As we moved down a level in the tree, we toggled the direction of the split in the rectangles from vertical to horizontal or vice versa. The root node's size in the current rectangle corresponded to its relative weight in the current subtree. The structure of the tree could be inferred by the relationships among the rectangles and their relative widths and heights. We drew several of these embeddings by hand and noted that the patterns resembled art by the Dutch abstract artist Piet Mondrian [6]. We then implemented this visualization using the Java Power Tools [4] library and noted that this visualization can be enriched with colors and graphical patterns, as in the Kaleidoscope example [3]. Our idea is an active research area in computer graphics [7]. However, it still appears to be a novel teaching idea for CS2. Ben Shneiderman [5] was the first to study two-dimensional space-filling representations of trees; he called them "treemaps". His motivating problem was to visualize directories in order to determine disk utilization. His algorithm was similar to our algorithm. XML documents can also be visualized using his algorithm and others [1]. Our goal is to synthesize this treemap visualization literature [1, 5] into classroom materials for CS2 instructors.
Computing Nash equilibria for scheduling on restricted parallel links
Authors: Martin Gairing, Thomas Lücking, Marios Mavronicolas, Burkhard Monien
Venue: Proceedings of the thirty-sixth annual ACM symposium on Theory of computing (2004)

We consider the problem of routing n users on m parallel links, under the restriction that each user may only be routed on a link from a certain set of allowed links for the user. Thus, the problem is equivalent to the correspondingly restricted problem of assigning n jobs to m parallel machines. In a pure Nash equilibrium, no user may improve its own individual cost (delay) by unilaterally switching to another link from its set of allowed links. As our main result, we introduce a polynomial time algorithm to compute from any given assignment a pure Nash equilibrium with non-increased makespan. The algorithm gradually changes a given assignment by pushing unsplittable user traffics through a network that is defined by the users and the links. Here, we use ideas from blocking flows. Furthermore, we use similar techniques as in the generic Preflow-Push algorithm to approximate a schedule with minimum makespan, gaining an improved approximation factor of 2 - 1/w1 for identical links, where w1 is the largest user traffic. We extend this result to related links, gaining an approximation factor of 2. Our approximation algorithms run in polynomial time. We close with tight upper bounds on the coordination ratio for pure Nash equilibria.
Filtering algorithms for information retrieval models with named attributes and proximity operators
Authors: Christos Tryfonopoulos, Manolis Koubarakis, Yannis Drougas
Venue: Proceedings of the 27th annual international ACM SIGIR conference on Research and development in information retrieval (2004)

In the selective dissemination of information (or publish/subscribe) paradigm, clients subscribe to a server with continuous queries (or profiles) that express their information needs. Clients can also publish documents to servers. Whenever a document is published, the continuous queries satisfying this document are found and notifications are sent to appropriate clients. This paper deals with the filtering problem that needs to be solved effciently by each server: Given a database of continuous queries db and a document d, find all queries q ∈ db that match d. We present data structures and indexing algorithms that enable us to solve the filtering problem efficiently for large databases of queries expressed in the model AWP which is based on named attributes with values of type text, and word proximity operators.
Supporting Public Software Acquisition Workflows - Implications for Data Models
Authors: Werner Aigner, Peter Regner, Thomas Wiesinger, Josef Kung
Venue: Proceedings of the Database and Expert Systems Applications, 15th International Workshop (2004)

Many software acquisition projects are doomed to fail due to a lack of integration of acquisition and development processes on the one hand and, because of shortcomings of classic software development processes on the other hand. In our studies we focus on public sector where legal restrictions make software acquisition more challenging than in private sector. As a consequence we developed an approach for interlocking development processes and acquisition processes using the negotiated procedure. Current award platforms only support publication of documents produced in acquisition process. In contrast to the state of the art we are developing a web based public tender support system called PTSS that uses our approach guiding all stakeholders playing different roles supporting iterative procedures proposed by software development processes like eXtreme Programming or the Rational Unified Process. This role based approach has basic impact on data models and other design targets we discuss in this paper.
Hair Paint
Authors: Benjamin Hernandez, Isaac Rudomin
Venue: Proceedings of the Computer Graphics International (2004)

Adding hair to virtual humans has focused on threeimportant aspects: hair modeling, hair animation andhair rendering. We present an easy-to-use tool forhairstyling, modeling and animation of hair in realtime. For modeling we use a paint-based interface tospecify geometrical and styling characteristics of hairwhile for animation we use a simplified physical basedapproximation.
Some properties of the happy numbers and the Smarandache H-sequence
Authors: Charles Ashbacher
Venue: Smarandache Notions Journal (2004)

The happy numbers are those where the iterated sums of the squares of the digits terminates at 1. A Smarandache Concatenate Sequence is a set of numbers formed by the repeated concatenation of the elements of another set of numbers. In this paper, we examine some of the properties of the happy numbers as well as a concatenation sequence constructed from the happy numbers.
A new approach based on soft computing to accelerate the selection of new product ideas
Authors: Gülçin Büyüközkan, Orhan Feyzioǧlu
Venue: Computers in Industry (2004)

The aim of this study is to accelerate new product introduction and to improve the quality of decision-making in new product development (NPD) process under uncertain conditions. We first present the uncertainty factors related to NPD and also give existing decision-making techniques that help the decision makers to reduce their risks under uncertainty. Basically, we are interested in two stages of new product decision-making: the choice of a new product idea ("go"/"no go" decision) and the choice of the right implementation order of the selected product ideas. To achieve this, we propose an integrated approach based on fuzzy logic, neural networks and multi criteria decision-making to make the most appropriate decisions. By utilizing artificial intelligent techniques, we manage to accelerate the selection process. Finally, a case study in a toy manufacturing firm is given to demonstrate the potential of the methodology.
ARCO " An Architecture for Digitization, Management and Presentation of Virtual Exhibitions
Authors: Martin White, Nicholaos Mourkoussis, Joe Darcy, Panos Petridis, Fotis Liarokapis, Paul Lister, Krzysztof Walczak, Rafa" Wojciechowski, Wojciech Cellary, Jacek Chmielewski, Miros"aw Stawniak, Wojciech Wiza, Manjula Patel, James Stevenson, John Manley, Fabrizio Giorgini, Patrick Sayd, Francois Gaspard
Venue: Proceedings of the Computer Graphics International (2004)

A complete tool chain starting with stereophotogrammetry based digitization of artefacts, theirrefinement, collection and management with othermultimedia data, and visualization using virtual andaugmented reality is presented. Our system provides aone-stop-solution for museums to create, manage andpresent both content and context for virtualexhibitions. Interoperability and standards are alsokey features of our system allowing both small andlarge museums to build a bespoke system suited totheir needs.
Desktop scheduling: how can we know what the user wants?
Authors: Yoav Etsion, Dan Tsafrir, Dror G. Feitelson
Venue: Proceedings of the 14th international workshop on Network and operating systems support for digital audio and video (2004)

Current desktop operating systems use CPU utilization (or lack thereof) to prioritize processes for scheduling. This was thought to be beneficial for interactive processes, under the assumption that they spend much of their time waiting for user input. This reasoning fails for modern multimedia applications. For example, playing a movie in parallel with a heavy background job usually leads to poor graphical results, as these jobs are indistinguishable in terms of CPU usage. Suggested solutions involve shifting the burden to the user or programmer, which we claim is unsatisfactory; instead, we seek an automatic solution. Our attempts using new metrics based on CPU usage failed. We therefore propose and implement a novel scheme of identifying interactive and multimedia applications by directly quantifying the I/O between an application and the user (keyboard, mouse, and screen activity). Preliminary results indicate that prioritizing processes according to this metric indeed solves the aforementioned problem, demonstrating that operating systems can indeed provide better support for multimedia and interactive applications. Additionally, once user I/O data is available, it opens intriguing new possibilities to system designers.
Workflow Management Systems and ERP Systems: Differences, Commonalities, and Applications
Authors: Jorge Cardoso, Robert P. Bostrom, Amit Sheth
Venue: Information Technology and Management (2004)

Two important classes of information systems, Workflow Management Systems (WfMSs) and Enterprise Resource Planning (ERP) systems, have been used to support e-business process redesign, integration, and management. While both technologies can help with business process automation, data transfer, and information sharing, the technological approach and features of solutions provided by WfMS and ERP are different. Currently, there is a lack of understanding of these two classes of information systems in the industry and academia, thus hindering their effective applications. In this paper, we present a comprehensive comparison between these two classes of systems. We discuss how the two types of systems can be used independently or together to develop intra- and inter-organizational application solutions. In particular, we also explore the roles of WfMS and ERP in the next generation of IT architecture based on Web Services. Our findings should help businesses make better decisions in the adoption of both WfMS and ERP in their e-business strategies.
Possibilistic Databases and Generalized Yes/No Queries
Authors: Patrick Bosc, Olivier Pivert
Venue: Proceedings of the Database and Expert Systems Applications, 15th International Workshop (2004)

This pape is concerned with the handling of imprecise information in possibilistic relational databases.Since the processing of general algebraic queries raises severe problems in terms of tractability in the presence of imprecise information, a specific family of queries called generalized yes/no queries is considered.Their format is: "to what extent is it possible and certain that the answer to Q is non empty?".A strategy for processing such queries efficiently is proposed under some assumptions as to the operators appearing in the query Q.
Context-based methods for text categorisation
Authors: D. S. Hunnisett, W. J. Teahan
Venue: Proceedings of the 27th annual international ACM SIGIR conference on Research and development in information retrieval (2004)

We propose several context-based methods for text categorization. One method, a small modification to the PPM compression-based model which is known to significantly degrade compression performance, counter-intuitively has the opposite effect on categorization performance. Another method, called C-measure, simply counts the presence of higher order character contexts, and outperforms all other approaches investigated.
Integrating Model-Based Design and Preemptive Scheduling in Mixed Time- and Event-Triggered Systems
Authors: N. Scaife, P. Caspi
Venue: Proceedings of the 16th Euromicro Conference on Real-Time Systems (2004)

Model-based design is advocated as themethod of choice when dealing with critical systems aswell as high quality systems. However, it often abstractsimplementation details such as execution times. This canbe a problem when dealing with urgent events whoseimplementation requires preemptive scheduling. In this paper,we propose an inter-task communication mechanismon top of a fixed-priority deadline monotonic preemptiveexecution scheme, which preserves the ordering of computationsvalidated in a "zero-time" synchronous framework,and formally show its correctness.
Integrated Adaptive QoS Management in Middleware: A Case Study
Venue: Proceedings of the 10th IEEE Real-Time and Embedded Technology and Applications Symposium (2004)

Distributed real-time and embedded (DRE) systems inwhich application requirements and environmentalconditions may not be known a priori-or which may vary atrun-time-can benefit from an adaptive approach tomanagement of quality-of-service (QoS) to meet keyconstraints, such as end-to-end timeliness. Moreover,coordinated management of multiple QoS capabilities acrossmultiple layers of applications and their supportingmiddleware can help to achieve necessary assurances ofmeeting these constraints. This paper offers twocontributions to the study of adaptive DRE computingsystems: (1) a case study of our integration of multiplemiddleware QoS management technologies to managequality and timeliness of imagery adaptively within arepresentative DRE avionics system and (2) empirical resultsand analysis of the impact of that integration on key trade-offsbetween timeliness and image quality in that system.
Context-Centric Proactive Information Delivery
Authors: Xiaocong Fan, John Yen, Rui Wang, Shuang Sun, Richard A. Volz
Venue: Proceedings of the Intelligent Agent Technology, IEEE/WIC/ACM International Conference (2004)

Delivering only those information relevant to the needs of teammates is critical for avoiding information overload. Need-driven proactive information delivery has thus been widely investigated in diverse areas spanning from psychology, AI, to Web-based services. CAST, a team-oriented agent architecture, realized proactive information delivery as a built-in agent behavior, which is derived by the capability of anticipating others' information-needs based on a computational shared mental model. However, the first implementation of CAST is limited in managing the dynamic activation and deactivation of teammates' information-needs. This paper addresses this issue by proposing a novel mechanism for organizing and managing the "context" of information-needs, which facilitates information-needs to be activated and deactivated dynamically. We evaluate the proposed approach by comparing its performance with agent teams using only reactive communications (e.g., ask/reply) and with the original CAST agent teams.
COBBLER: Combining Column and Row Enumeration for Closed Pattern Discovery
Authors: Feng Pan, Anthony K. H. Tung, Gao Cong, Xin Xu
Venue: Proceedings of the 16th International Conference on Scientific and Statistical Database Management (2004)

The problem of mining frequent closed patterns has receivedconsiderable attention recently as it promises to have much lessredundancy compared to discovering all frequent patterns. Existingalgorithms can presently be separated into two groups,feature (column) enumeration and row enumeration. Featureenumeration algorithms like CHARM and CLOSET+ areefficient for datasets with small number of features and largenumber of rows since the number of feature combinations to beenumerated is small. Row enumeration algorithms like CARPENTERon the other hand are more suitable for datasets (eg.bioinformatics data) with large number of features and smallnumber of rows. Both groups of algorithms, however, will encounterproblem for datasets that have large number of rowsand features.In this paper, we describe a new algorithm called COBBLERwhich can efficiently mine such datasets . COBBLER isdesigned to dynamically switch between feature enumerationand row enumeration depending on the data characteristic inthe process of mining. As such, each portion of the datasetcan be processed using the most suitable method, making themining more efficient. Several experiments on real-life andsynthetic datasets show that COBBLER is an order of magnitudebetter than previous closed pattern mining algorithmslike CHARM, CLOSET+ and CARPENTER.
Secure XML querying with security views
Authors: Wenfei Fan, Chee-Yong Chan, Minos Garofalakis
Venue: Proceedings of the 2004 ACM SIGMOD international conference on Management of data (2004)

The prevalent use of XML highlights the need for a generic, flexible access-control mechanism for XML documents that supports efficient and secure query access, without revealing sensitive information unauthorized users. This paper introduces a novel paradigm for specifying XML security constraints and investigates the enforcement of such constraints during XML query evaluation. Our approach is based on the novel concept of security views, which provide for each user group (a) an XML view consisting of all and only the information that the users are authorized to access, and (b) a view DTD that the XML view conforms to. Security views effectively protect sensitive data from access and potential inferences by unauthorized user, and provide authorized users with necessary schema information to facilitate effective query formulation and optimization. We propose an efficient algorithm for deriving security view definitions from security policies (defined on the original document DTD) for different user groups. We also develop novel algorithms for XPath query rewriting and optimization such that queries over security views can be efficiently answered without materializing the views. Our algorithms transform a query over a security view to an equivalent query over the original document, and effectively prune query nodes by exploiting the structural properties of the document DTD in conjunction with approximate XPath containment tests. Our work is the first to study a flexible, DTD-based access-control model for XML and its implications on the XML query-execution engine. Furthermore, it is among the first efforts for query rewriting and optimization in the presence of general DTDs for a rich a class of XPath queries. An empirical study based on real-life DTDs verifies the effectiveness of our approach.
Diamond in the rough: finding Hierarchical Heavy Hitters in multi-dimensional data
Authors: Graham Cormode, Flip Korn, S. Muthukrishnan, Divesh Srivastava
Venue: Proceedings of the 2004 ACM SIGMOD international conference on Management of data (2004)

Data items archived in data warehouses or those that arrive online as streams typically have attributes which take values from multiple hierarchies (e.g., time and geographic location; source and destination IP addresses). Providing an aggregate view of such data is important to summarize, visualize, and analyze. We develop the aggregate view based on certain hierarchically organized sets of large-valued regions ("heavy hitters"). Such Hierarchical Heavy Hitters (HHHs) were previously introduced as a crucial aggregation technique in one dimension. In order to analyze the wider range of data warehousing applications and realistic IP data streams, we generalize this problem to multiple dimensions.We identify and study two variants of HHHs for multi-dimensional data, namely the "overlap" and "split" cases, depending on how an aggregate computed for a child node in the multi-dimensional hierarchy is propagated to its parent element(s). For data warehousing applications, we present offline algorithms that take multiple passes over the data and produce the exact HHHs. For data stream applications, we present online algorithms that find approximate HHHs in one pass, with provable accuracy guarantees.We show experimentally, using real and synthetic data, that our proposed online algorithms yield outputs which are very similar (virtually identical, in many cases) to their offline counterparts. The lattice property of the product of hierarchical dimensions ("diamond") is crucially exploited in our online algorithms to track approximate HHHs using only a small, fixed number of statistics per candidate node, regardless of the number of dimensions.
Computer Aided Tolerance Analysis and Synthesis in Micro Systems (&mu;-ToAST)
Authors: Christoph Germer, Ulli Hansen, Hans-Joachim Franke, Stephanus Büttgenbach
Venue: Analog Integrated Circuits and Signal Processing (2004)

The large variety of the technologies and physical, chemical or biochemical effects united in micro systems requires a new generation of quality assurance. An appropriate quality management should check all conceivable influences on the product and perform a complete tolerance synthesis based on its function and with regard to manufacturing and cost optimization. In the following a new approach to function-oriented tolerance analysis and synthesis is presented.The authors have developed a computer program which assists Design Engineers in tolerance analysis and synthesis in micro technology. This contribution presents the theoretical background and the basic functionality of this software. For a better understanding a short MEMS example is shown.