ppxscal/embedding_network huggingface dataset:
Exact Algorithm for Minimising the Number of Setups in the One-Dimensional Cutting Stock Problem
Authors: François Vanderbeck
Venue: Operations Research (2000)

The cutting stock problem is that of finding a cutting of stock material to meet demands for small pieces of prescribed dimensions while minimising the amount of waste. Because changing over from one cutting pattern to another involves significant setups, an auxiliary problem is to minimise the number of different patterns that are used. The pattern minimisation problem is significantly more complex, but it is of great practical importance. In this paper, we propose an integer programming formulation for the problem that involves an exponential number of binary variables and associated columns, each of which corresponds to selecting a fixed number of copies of a specific cutting pattern. The integer program is solved using a column generation approach where the subproblem is a nonlinear integer program that can be decomposed into multiple bounded integer knapsack problems. At each node of the branch-and-bound tree, the linear programming relaxation of our formulation is made tighter by adding super-additive inequalities. Branching rules are presented that yield a balanced tree. Incumbent solutions are obtained using a rounding heuristic. The resulting branch-and-price-and-cut procedure is used to produce optimal or approximately optimal solutions for a set of real-life problems.
Symbolic NFA scheduling of a RISC microprocessor
Authors: Forrest Brewer, Steve Haynal
Venue: IEEE Transactions on Very Large Scale Integration (VLSI) Systems (2002)

We describe a set of techniques for representing the high-level behavior of a digital subsystem as a collection of nondeterministic finite automata, NFA. Desired behavioral dynamics such as functional dependencies, sequential timing, and sequencing, and control state are similarly modeled. Using techniques similar to that used in formal model checking, we implicitly explore the possible execution sequences of the system, obeying all imposed constraints. This provides a very general, systematic mechanism for performing high-level synthesis of cyclic, control dominated behaviors, constrained by arbitrary sequential constraints. In this paper, we show that these techniques are scalable to practical problem sizes and complexities by constructing a high-level model of a (MIPS IV) RISC Microprocessor and then performing exact scheduling and related design tradeoffs on this model. The model is constructed at the level of register transactions to address the majority of contention and arbitration issues of architectural interest.
Advancements in 3D interactive devices for virtual environments
Authors: D. Wormell, E. Foxlin
Venue: Proceedings of the workshop on Virtual environments 2003 (2003)

New commercially available interactive 3D tracking devices and systems for use in virtual environments are discussed. InterSense originally introduced the IS-900 scalable-area hybrid tracking system for virtual environments in 1999. In response to customer requests, we have almost completely revamped the system over the past two years. The major changes include a drastic 3-fold reduction in the size and weight of the wearable sensor devices, introduction of wireless tracking capability, a standardized I2C interface to allow OEM system integrators to add additional custom controls, and evolution of the system software interfaces, the performance, and the price. This paper will briefly describe the underlying technology changes that have allowed these advances to occur, and will outline some of the configuration possibilities that are now supported. Specific examples of how these devices and systems are being used to improve productivity in oil & gas seismic analysis & well field planning; automotive design & test; and, industrial/military training applications will be used to illustrate. Customization standards and future developments are discussed.
Novel techniques for robust voxelization and visualization of implicit surfaces
Authors: Nilo Stolte, Arie Kaufman
Venue: Graphical Models (2001)

Voxelization is the transformation of geometric surfaces into voxels. Up to date this process has been done essentially using incremental algorithms. Incremental algorithms have the reputation of being efficient but they lack an important property: robustness. The voxelized representation should envelop its continuous model. However, without robust methods this cannot be guaranteed. This article describes novel techniques of robust voxelization and visualization of implicit surfaces. First of all our recursive subdivision voxelization algorithm is reviewed. This algorithm was initially inspired by Duff's image space subdivision method. Then, we explain the algorithm to voxelize implicit surfaces defined in spherical or cylindrical coordinates. Next, we show a new technique to produce infinite replications of implicit objects and their voxelization method. Afterward, we comment on the parallelization of our voxelization procedure. Finally we present our voxel visualization algorithm based on point display. Our voxelization algorithms can be used with any data structure, thanks to the fact that a voxel is only stored once the last subdivision level is reached. We emphasize the use of the octree, though, because it is a convenient way to store the discrete model hierarchically. In a hierarchy the discrete model refinement is simple and possible from any previous voxelized scene thanks to the fact that the voxelization algorithms are robust.
Analysis of Vowels in Sung Queries for a Music Information Retrieval System
Authors: Maureen Mellody, Mark A. Bartsch, Gregory H. Wakefield
Venue: Journal of Intelligent Information Systems (2003)

A method for analyzing and categorizing the vowels of a sung query is described and analyzed. This query system uses a combination of spectral analysis and parametric clustering techniques to divide a single query into different vowel regions. The method is applied separately to each query, so no training or repeated measures are necessary. The vowel regions are then transformed into strings and string search methods are used to compare the results from various songs. We apply this method to a small pilot study consisting of 40 sung queries from each of 7 songs. Approximately 60% of the queries are correctly identified with their corresponding song, using only the vowel stream as the identifier.
Minors in graphs of large girth
Authors: Daniela Kühn, Deryk Osthus
Venue: Random Structures Algorithms (2003)

We show that for every odd integer g ≥ 5 there exists a constant c such that every graph of minimum degree r and girth at least g contains a minor of minimum degree at least cr(g+1)/4. This is best possible up to the value of the constant c for g = 5, 7, and 11. More generally, a well-known conjecture about the minimal order of graphs of given minimum degree and large girth would imply that our result gives the correct order of magnitude for all odd values of g. The case g = 5 of our result implies Hadwiger's conjecture for C4-free graphs of sufficiently large chromatic number.
Query-preserving watermarking of relational databases and XML documents
Authors: David Gross-Amblard
Venue: Proceedings of the twenty-second ACM SIGMOD-SIGACT-SIGART symposium on Principles of database systems (2003)

Watermarking allows robust and unobtrusive insertion of information in a digital document. Very recently, techniques have been proposed for watermarking relational databases or XML documents, where information insertion must preserve a specific measure on data (e.g. mean and variance of numerical attributes.)In this paper we investigate the problem of watermarking databases or XML while preserving a set of parametric queries in a specified language, up to an acceptable distortion.We first observe that unrestricted databases can not be watermarked while preserving trivial parametric queries. We then exhibit query languages and classes of structures that allow guaranteed watermarking capacity, namely 1) local query languages on structures with bounded degree Gaifman graph, and 2) monadic second-order queries on trees or tree-like structures. We relate these results to an important topic in computational learning theory, the VC-dimension. We finally consider incremental aspects of query-preserving watermarking.
Secure buffering in firm real-time database systems
Authors: Binto George, Jayant R. Haritsa
Venue: The VLDB Journal &mdash; The International Journal on Very Large Data Bases (2000)

Many real-time database applications arise in electronic financial services, safety-critical installations and military systems where enforcing is crucial to the success of the enterprise. We investigate here the performance implications, in terms of killed transactions, of guaranteeing multi-level secrecy in a real-time database system supporting applications with firm deadlines. In particular, we focus on the buffer management aspects of this issue.Our main contributions are the following. First, we identify the importance and difficulties of providing secure buffer management in the real-time database environment. Second, we present , a novel buffer management algorithm that provides covert-channel-free security. SABRE employs a fully dynamic one-copy allocation policy for efficient usage of buffer resources. It also incorporates several optimizations for reducing the overall number of killed transactions and for decreasing the unfairness in the distribution of killed transactions across security levels. Third, using a detailed simulation model, the real-time performance of SABRE is evaluated against unsecure conventional and real-time buffer management policies for a variety of security-classified transaction workloads and system configurations. Our experiments show that SABRE provides security with only a modest drop in real-time performance. Finally, we evaluate SABRE's performance when augmented with the GUARD adaptive admission control policy. Our experiments show that this combination provides close to ideal fairness for real-time applications that can tolerate covert-channel bandwidths of up to one bit per second (a limit specified in military standards).
Stochastic Vehicle Routing with Random Travel Times
Authors: Astrid S. Kenyon, David P. Morton
Venue: Transportation Science (2003)

We consider stochastic vehicle routing problems on a network with random travel and service times. A fleet of one or more vehicles is available to be routed through the network to service each node. Two versions of the model are developed based on alternative objective functions. We provide bounds on optimal objective function values and conditions under which reductions to simpler models can be made. Our solution method embeds a branch-and-cut scheme within a Monte Carlo sampling-based procedure.
Islands of Shared Knowledge: Specialization and Mutual Understanding in Problem-Solving Teams
Authors: Steven Postrel
Venue: Organization Science (2002)

Where should the boundaries of knowledge between economic actors be located in order to maximize the efficiency of their interactions? In particular, what circumstances determine whether it makes sense for adjacent stages in the value chain to invest in the development of common understanding, and when does it make sense for them to operate in mutual ignorance? To address these questions, it is necessary to construct a kind of production function which takes different forms of knowledge -- specialist capability and trans-specialist understanding --as inputs and relates them to problem-solving output.Using a simple model of product design as a template, it is possible to derive such a production function. One can then use its properties in conjunction with plausible assumptions about the cost of acquiring different kinds of knowledge to develop general principles that explain when efficiency requires costly learning across specialties and when it is better to allow specialties to operate in mutual ignorance of one another's domains. The derived production function, contrary to some intuition and previous literature, implies that specialist capability cansubstitute for knowledge shared across specialties. This result in turn implies that the nature of learning costs, rather than the shape of knowledge benefits, plays the predominant role in determining when mutual ignorance is a good idea.The analysis also helps resolve the following paradox: The economy depends for its efficiency upon a drastic separation of knowledge across individuals and organizational units, yet studies of product development find that greater knowledge commonality is associated with better firm performance. An implication of the substitutability of specialized and trans-specialty knowledge is that situations where learning across specialties is desirable seem relatively rare in the economy as a whole. These situations are disproportionately common, however, in those areas where important managerial activity takes place. A key role of management is to attend to the strategic, operational, and governance needs of these "islands of shared knowledge in a sea of mutual ignorance."
Understanding Post-Adoption Behavior in the Context of Online Services
Authors: Madhavan Parthasarathy, Anol Bhattacherjee
Venue: Information Systems Research (1998)

This paper examines post-adoption behavior (continued adoption versus discontinuance) within the context of online service use. Innovation diffusion theory is used as a theoretical framework to extend information technology adoption research to the case of post-adoption behavior. This theory is used to formulate 11 research hypotheses distinguishing discontinuers from continuing adopters and exploring reasons behind their discontinuance (replacement versus disenchantment). These hyp otheses were then empirically tested using data collected from a field survey of online service users. Our results indicate that potential discontinuers can be discriminated from continued adopters based on their sources of influence (external and interpe rsonal), perceived service attributes (usefulness and compatibility), service utilization, and network externality (complementary product usage), during their time of initial adoption. We also found that later adopters are more likely to discontinue due to disenchantment than replacement, and are more influenced by interpersonal sources and utilize the service less during their adoption period than replacement discontinuers. Implications for research and practice are drawn.
The Choice Between Joint Venture and Wholly Owned Subsidiary: An Institutional Perspective
Authors: Daphne Yiu, Shige Makino
Venue: Organization Science (2002)

The study of foreign entry-mode choice has been based almost exclusively on transaction-cost theory. This theory focuses mainly on the impacts of firm- and industry-specific factors on the choice of entry mode, taking the effects of country-specific contextual factors as constant or less important. In contrast, the institutional perspective emphasizes the importance of the influence of both institutional forces embedded in national environments and decision makers' cognitive constraints on the founding conditions of new ventures. Still, this theoretical perspective has yet to provide insights into how institutional factors influence the choice of foreign entry mode. The primary goal of the present study is to provide a unifying theoretical framework to examine this relationship. We synthesize transaction-cost and institutional perspectives to analyze a sample of 364 Japanese overseas subsidiaries. Our results support the notion that institutional theory provides incremental explanatory power of foreign entry-mode choice in addition to transaction-cost theory. In particular, we found that multinational enterprises tend to conform to the regulative settings of the host-country environment, the normative pressures imposed by the local people, and the cognitive mindsets as bounded by counterparts' and multinational enterprises' own entry patterns when making foreign entry-mode choices.
Microarchitectural exploration with Liberty
Authors: Manish Vachharajani, Neil Vachharajani, David A. Penry, Jason A. Blome, David I. August
Venue: Proceedings of the 35th annual ACM/IEEE international symposium on Microarchitecture (2002)

To find the best designs, architects must rapidly simulate many design alternatives and have confidence in the results. Unfortunately, the most prevalent simulator construction methodology, hand-writing monolithic simulators in sequential programming languages, yields simulators that are hard to retarget, limiting the number of designs explored, and hard to understand, instilling little confidence in the model. Simulator construction tools have been developed to address these problems, but analysis reveals that they do not address the root cause, the error-prone mapping between the concurrent, structural hardware domain and the sequential, functional software domain. This paper presents an analysis of these problems and their solution, the Liberty Simulation Environment (LSE). LSE automatically constructs a simulator from a machine description that closely resembles the hardware, ensuring fidelity in the model. Furthermore, through a strict but general component communication contract, LSE enables the creation of highly reusable component libraries, easing the task of rapidly exploring ever more exotic designs.
Formal verification of the FPGA cores
Authors: Carl Johan Lillieroth, Satnam Singh
Venue: Nordic Journal of Computing (1999)

A formal verification technique is presented which is suitable for the verification of standard components (cores) for programmable hardware (FPGAs). This technique can be viewed as a suitable complement to traditional techniques, such as simulation. We describe the modelling and verification of combinational and sequential components using the formal verification tool NP-Tools, and report successful verification of real cores.
An approach to stopping problems of a dynamic fuzzy system
Authors: Masami Kurano, Masami Yasuda, Jun-ichi Nakagami, Yuji Yoshida
Venue: Fuzzy Sets and Systems (2002)

We formulate a stopping problem for dynamic fuzzy systems concerning with fuzzy decision environment. It could be regarded as a natural fuzzification of non-fuzzy stopping problem with a deterministic dynamic system. The validity of the approach by α-cuts of fuzzy sets will be discussed in constructing One-step Look Ahead policy of an optimal fuzzy stopping time. A numerical example is given to illustrate the theoretical results and to show a merit to use fuzzy stopping times in dynamic fuzzy systems.
Protocol for Large-Scale Group
Authors: Kojiro Taguchi, Makoto Takizawa
Venue: Proceedings of the 13th International Workshop on Database and Expert Systems Applications (2002)

We discuss a novel type of group communication protocol for a large number of processes. Group communication among a large number of processes implies large computation and communication overheads for manipulating and transmitting messages since computation and communication overheads are O(n2) for number n of processes. In this paper, we discuss a hierarchical group which is composed of subgroups of processes.
An Efficient Technique of Instruction Scheduling on a Superscalar-Based Mulprocessor
Authors: Rong-Yuh Hwang
Venue: Proceedings of the 11th International Symposium on Parallel Processing (1997)

An instruction scheduling approach is proposed for performance enhancement on a superscalar-based multiprocessor. The traditional list scheduling approach is not suitable for the environment because it does not consider the effect of synchronization operation. According to the LBD loop theorem, the system performance is very concerned with the position of synchronization operation. Therefore, the scheduling of synchronization operation has the highest priority in this technique. There are two aspects of performance enhancement for the instruction scheduling approach: 1) converting LBD into LFD, and 2) reducing the damage of LBD. Experimental results show that the enhancement is significant. The ACM Portal is published by the Association for Computing Machinery. Copyright © 2010 ACM, Inc. Terms of Usage Privacy Policy Code of Ethics Contact Us Useful downloads: Adobe Acrobat QuickTime Windows Media Player Real Player
Approximation schemes for propagation of fronts with nonlocal velocities and Neumann boundary conditions
Authors: Dejan Slepčev
Venue: Nonlinear Analysis: Theory, Methods Applications (2003)

The convergence of schemes for propagation of fronts in a bounded domain moving with normal velocities is studied. The velocities considered depend on the principal curvatures, the normal direction, the location, as well as some nonlocal properties of the front. Most of the schemes considered are in essence threshold dynamics type approximation schemes, modified for Neumann boundary conditions and nonlocal terms. The existence and uniqueness of appropriately defined viscosity solutions of the level-set equations describing the nonlocal motions is also shown.
Access Support Tree TextArray: A Data Structure for XML Document Storage Retrieval
Authors: Dieter Scheffner, Johann Christoph Freytag
Venue: Proceedings of the 14th International Conference on Scientific and Statistical Database Management (2002)

The characteristics of XML documents require new ways of storing and querying such documents. Queries on both textual content and structural aspects must be supported efficiently. For this reason, we examined existing work on both document storage approaches and models for querying documents to derive requirements that are essential for the storage of XML documents. As a result of our study, we designed the Access Support Tree and Text Array (AST/TA) data structure. The important idea of the AST/TA data structure is the separation of the (logical) structure of a document from its "visible" text content. The latter is represented as a single contiguous string. At the same time the AST/TA data structure provides a tight integration to guarantee consistent changes. We introduce the AST/TA datastructure formally by its abstraction, namely the AST/TA model and compare requirements of our AST/TA approach with those found in the current literature. Finally, we describe the advantage of the AST/TA model based on the AST/TA design principles.
On the issue of consistency in dynamical consensual aggregation
Authors: Mario Fedrizzi, Michele Fedrizzi, R. A. Marques Pereira
Venue: Technologies for constructing intelligent systems: Tasks (2002)

In this paper we propose to use the consistency of preferences in order to endogenously assign different weights to decision makers in a consensual dynamics process. For this purpose, we first define a consistency index for preferences expressed by means of fuzzy preference relations. Then we introduce this index in an iterative law for updating the individual preferences. The updating law is formulated in the spirit of some previous papers on consensual dynamics (see for instance [5]) and, as a result, both the initially declared preferences and the present ones (in the ongoing process) act with a strength determined on the basis of their consistency.