ppxscal/embedding_network huggingface dataset:
Directions of Motion Fields are Hardly Ever Ambiguous
Authors: Tomas Brodsky, Cornelia Fermüller, Yiannis Aloimonos
Venue: International Journal of Computer Vision (1998)

If instead of the full motion field, we consider only the direction of the motion field due to a rigid motion, what can we say about the three-dimensional motion information contained in it? This paper provides a geometric analysis of this question based solely on the constraint that the depth of the surfaces in view is positive. The motivation behind this analysis is to provide a theoretical foundation for image constraints employing only the sign of flow in various directions and justify their utilization for addressing 3D dynamic vision problems.It is shown that, considering as the imaging surface the whole sphere, independently of the scene in view, two different rigid motions cannot give rise to the same directional motion field. If we restrict the image to half of a sphere (or an infinitely large image plane) two different rigid motions with instantaneous translational and rotational velocities(t<math>_1 &omega;_1) and(t<math>_2 ,&omega;_2) cannot give rise to the same directional motion field unless the plane through t_1 and t_2 is perpendicular to the plane through &omega;_1 and &omega;_2 (i.e., (t_1 &times; t_2) &middot; (&omega;_1 &times; &omega;_2) &equals; 0. In addition, in order to give practical significance to these uniqueness results for the case of a limited field of view, we also characterize the locations on the image where the motion vectors due to the different motions must have different directions.If (&omega;_1 &times; &omega;_2) &middot; (t_1 &times; t_2) &equals; 0 and certain additional constraints are met, then the two rigid motions could produce motion fields with the same direction. For this to happen the depth of each corresponding surface has to be within a certain range, defined by a second and a third order surface. Similar more restrictive constraints are obtained for the case of multiple motions. Consequently, directions of motion fields are hardly ever ambiguous. A byproduct of the analysis is that full motion fields are never ambiguous with a half sphere as the imaging surface.
Complexity, ontology, and the causal Markov assumption
Authors: Paul B. Losiewicz
Venue: ACM SIGART Bulletin (1996)

The question of what constitutes a causal model is significant, as it will lead to a better understanding of the role of causality and its heuristic role in probabilistic reasoning. It has been argued that in certain cases domain specific considerations can be appealed to in the construction of more efficient causal models that are "nonstandard" in the way networks reflect anomalous correlations between nodes. For the most part, the causal assumptions generally invoked [Pearl 1988], [Spirtes, Glymour, Scheines 1993] do lead to systematic efficiencies based on a reduction in computational requirements for the models they produce. The goal of this paper is to uncover some of the assumptions about causality that undergird current causal models, assumptions which should be kept in mind by those invoking causal relations in the construction of discovery algorithms for causal networks.
Subtypes for Specifications: Predicate Subtyping in PVS
Authors: John Rushby, Sam Owre, Natarajan Shankar
Venue: IEEE Transactions on Software Engineering (1998)

A specification language used in the context of an effective theorem prover can provide novel features that enhance precision and expressiveness. In particular, typechecking for the language can exploit the services of the theorem prover. We describe a feature called "predicate subtyping" that uses this capability and illustrate its utility as mechanized in PVS.
Computational structure of a performance assessment involving stochastic and subjective uncertainty
Authors: Jon C. Helton
Venue: Proceedings of the 28th conference on Winter simulation (1996)

A recent performance assessment for the Waste Isolation Pilot Plant (WIPP), which is being developed by the U.S. Department of Energy for the geologic disposal of transuranic waste, is used to illustrate the computational structure of a large analysis that maintains a separation between stochastic (i.e., aleatory) and subjective (i.e., epistemic) uncertainty. In this analysis, stochastic uncertainty arises from the many possible disruptions that could occur over the 10,000 yr regulatory period that applies to the WIPP, and subjective uncertainty arises from the imprecision with which many of the quantities required in the analysis are known. Important parts of the computational structure are (1) the use of Latin hyper cube sampling to incorporate the effects of subjective uncertainty, (2) the use of Monte Carlo (i.e., random) sampling to incorporate the effects of stochastic uncertainty, and (3) the efficient use of the necessarily limited number of mechanistic calculations that can be performed to support the analysis.
Efficient Implementation Methodology of Fast FIR Filtering Algorithms on DSP
Authors: Anissa Zergaïnoh, Pierre Duhamel, Jean Pierre Vidal
Venue: Journal of VLSI Signal Processing Systems (1997)

A class of Finite Impulse Response (FIR) filtering algorithms based either on short Fast Fourier Transforms (FFT) or on short length FIR filtering algorithms was recently proposed. Besides the significant reduction of the arithmetic complexity, these algorithms present some characteristics which make them useful in many applications, namely a small delay processing (independent on the FIR filter length) as well as a multiply-add based computational structure. These algorithms are presented in a unified framework, thus allowing an easy combination of any of them. However, a remaining difficulty concerns the implementation of the fast algorithms on Digital Signal Processors (DSP), given the DSP finite resources (number of pointers, registers and memory), while keeping as much as possible the improvement brought by the reduction of the arithmetic complexity. This paper provides an efficient implementation methodology, by organizing the algorithm in such a way that the memory data access is optimized on a DSP. As a result, our implementation requires a constant number of pointers whatever the algorithm combination. This knowledge is used in a DSP code generator which is able to select the appropriate algorithm meeting the application constraints, as well as to generate automatically an optimized assembly code, using macro-instructions available in a DSP-dependent library. An improvement of more than 50% in terms of throughput (number of machine cycles per point) compared to the implementation of the direct convolution is generally achieved.
Power supply noise analysis methodology for deep-submicron VLSI chip design
Authors: Howard H. Chen, David D. Ling
Venue: Proceedings of the 34th annual Design Automation Conference (1997)

This paper describes a new design methodology to analyzethe on-chip power supply noise for high-performance microprocessors.Based on an integrated package-level andchip-level power bus model, and a simulated switching circuitmodel for each functional block, this methodology offersthe most complete and accurate analysis of Vdd distributionfor the entire chip. The analysis results not only providedesigners with the inductive ¿I noise and the resistive IRdrop data at the same time, but also allow designers to easilyidentify the hot spots on the chip and ¿V across the chip.Global and local optimization such as buffer sizing, powerbus sizing, and on-chip decoupling capacitor placement canthen be conducted to maximize the circuit performance andminimize the noise.
Reducing the complexity of ILP formulations for synthesis
Authors: Anne Mignotte, Olivier Peyran
Venue: Proceedings of the 10th international symposium on System synthesis (1997)

Integer Linear Programming (ILP) is commonly used in high level and system level synthesis. It is an NP-Complete problem (in general cases). There exists some tools that give an optimal solution for small ILP formulations. Nevertheless, these tools may not give solutions for complex formulations. In this paper, we present a solution to overcome the problem of complexity in ILP formulations. We propose a partitioning methodology based on a constraint graph representing all the constraints included in any ILP formulation. To direct the partitioning, the constraint graph nodes are grouped to represent Data Flow Graph (DFG) nodes. This reduced constraint graph can be used to partition any ILP formulation based on DFG. We illustrate this method on ILP formulation for scheduling. Results on ILP scheduling formulations are promising.
Uncertainty Propagation in Model-Based Recognition
Authors: T. D. Alter, David W. Jacobs
Venue: International Journal of Computer Vision (1998)

Robust recognition systems require a careful understanding of the effects of error in sensed features. In model-based recognition, matches between model features and sensed image features typically are used to compute a model pose and then project the unmatched model features into the image. The error in the image features results in uncertainty in the projected model features. We first show how error propagates when poses are based on three pairs of 3D model and 2D image points. In particular, we show how to simply and efficiently compute the distributed region in the image where an unmatched model point might appear, for both Gaussian and bounded error in the detection of image points, and for both scaled-orthographic and perspective projection models. Next, we provide geometric and experimental analyses to indicate when this linear approximation will succeed and when it will fail. Then, based on the linear approximation, we show how we can utilize Linear Programming to compute bounded propagated error regions for any number of initial matches. Finally, we use these results to extend, from two-dimensional to three-dimensional objects, robust implementations of alignment, interpretation-tree search, and transformation clustering.
A case study of verification, validation, and accreditation for advanced distributed simulation
Authors: Ernest H. Page, Bradford S. Canova, John A. Tufarolo
Venue: ACM Transactions on Modeling and Computer Simulation (TOMACS) (1997)

The techniques and methodologies for verification and validation of software-based systems have arguably realized their greatest utility within the context of simulation. Advanced Distributed Simulation (ADS), a major initiative within the defense modeling and simulation community, presents a variety of challenges to the classical approaches. A case study of the development process and concomitant verification and validation activities for the Joint Training Confederation (JTC) is presented. The JTC is one of the largest current ADS efforts, and the primary application of the Aggregate Level Simulation Protocol. A dichotomy between classical verification and validation approaches and the requirements of a prototypical ADS environment is illustrated. Mechanisms and research directions to resolve these differences are briefly discussed.
A software pipelining based VLIW architecture and optimizing compiler
Authors: Bogong Su, Jian Wang, Zhizhong Tang, Wei Zhao, Yimin Wu
Venue: Proceedings of the 23rd annual workshop and symposium on Microprogramming and microarchitecture (1990)

This paper introduces a VLIW architecture and its optimizing compiler which are now under development. Based on the URPR software pipelining approach, the architecture integrates nine PEs with the same structure on a single-chip. In addition, a pipeline register file is used to reduce the inter-body dependent distance to enhance the overlapping of the adjacent loop iterations, furthermore to shorten the length of the optimized loop body. The pipeline register file also increases the bandwidth between PEs. The optimizing compiler is also based on the URPR software pipelining approach. It uses a two-level software pipelining method to implement phase-coupled resource allocation and code optimization, and obtains good time and space optimal results. A compilation example of an FFT innermost loop is discussed. The simulation results indicate that the architecture could reach high performance with the aid of the optimizing compiler.
Can the Sun&lsquo;s Direction be Estimated from an Image Prior to the Computation of Object Shape?
Authors: Wojciech Chojnacki, Michael J. Brooks, Daniel Gibbins
Venue: Journal of Mathematical Imaging and Vision (1997)

Various computational techniques have been developed that perform reasonably well in inferring shape from shading. However, these techniques typically require substantial prerequisite information if they are to evolve an estimate of surface shape. It is therefore interesting to consider how depth might be inferred from shading information without prior knowledge of various scene conditions. One approach has been to undertake a pre-processing step of estimating the light-source direction, thereby providing input to the computation of shape from shading. In this paper, we present evidence that a versatile light-source-direction estimator is unattainable, and propose that, in the absence of domain-specific knowledge, shape and light-source direction should be determined in a coupled manner
Interprocedural dataflow analysis in an executable optimizer
Authors: David W. Goodwin
Venue: Proceedings of the ACM SIGPLAN 1997 conference on Programming language design and implementation (1997)

Interprocedural dataflow information enables link-time and post-link-time optimizers to perform analyses and code transformations that are not possible in a traditional compiler. This paper describes the interprocedural dataflow analysis techniques used by Spike, a post-linktime optimizer for Alpha/NT executables. Spike uses dataflow analysis to summarize the register definitions, uses, and kills that occur external to each routine, allowing Spike to perform a variety of optimizations that require interprocedural dataflow information. Because Spike is designed to optimize large PC applications, the time required to perform interprocedural dataflow analysis could potentially be unacceptably long, limiting Spike's effectiveness and applicability. To decrease dataflow analysis time, Spike uses a compact representation of a program's intraprocedural and interprocedural control flow that efficiently summarizes the register definitions and uses that occur in the program. Experimental results are presented for the SPEC95 integer benchmarks and eight large PC applications. The results show that the compact representation allows Spike to compute interprocedural dataflow information in less than 2 seconds for each of the SPEC95 integer benchmarks. Even for the largest PC application containing over 1.7 million instructions in 340 thousand basic blocks, interprocedural dataflow analysis requires just 12 seconds.
Presto&mdash;A System Environment for Mission-CriticalMultimedia Applications
Authors: Jiandong Huang, Deepak Kenchammana-Hosekote, Mukul Agrawal, James Richardson
Venue: Real-Time Systems (1997)

Summarized in this report is a multiphased R and D program, presto, conducted for developing a multimedia system environment to support a variety of mission-critical applications. The concepts, software design, and system prototype developed during the first phase of the program are presented. In particular, the work on real-time scheduling, multimedia storage and retrieval, and application programming model is described. The major results of the presto Phase I program are a set of new techniques and system software for QoS- and criticality-based, adaptive multiresource management, raw-I/O-based continuous multimedia file management, and data flow-oriented programming with integrated real-time scheduling support.
A systematic approach for implementing fault tolerant software designs in Ada
Authors: John D. Litke
Venue: Proceedings of the conference on TRI-ADA '90 (1990)

This paper describes a new approach for implementing fault tolerant software in Ada. The approach uses automated analysis methods to determine appropriate low-complexity boundaries within the program. A subset of these boundaries defines fault-containment boundaries at which error semantics are specified. A disciplined method is proposed to implement these semantics using Ada's exception construct in such a way that an automated tool can verify the correct application of the method. The fault tolerance implementation method is compatible with object-oriented, data abstraction, and control abstraction program design methods.
Thermal Monitoring of Self-Checking Systems
Authors: V. Székely, M. Rencz, J. M. Karam, M. Lubaszewski, B. Courtois
Venue: Journal of Electronic Testing: Theory and Applications (1998)

With the increasing power density in integrated systems resulting from scaling down, the occurrence of field failures due to overheating has considerably increased. Faulty operation can be prevented by on-line temperature monitoring. This paper deals with questions of on-line temperature monitoring in safety-critical systems. First the possible temperature sensors are reviewed and basic principles of self-checking systems including such sensors are detailed, then a new temperature sensor cell with extremely good parameters designed especially for DfTT applications is presented. The basic questions of integrating thermal sensors into self-checking systems are also discussed.
Technology-dependent transformations for low-power synthesis
Authors: Rajendran Panda, Farid N. Najm
Venue: Proceedings of the 34th annual Design Automation Conference (1997)

We propose a methodology for applying gate-level logictransformations to optimize power in digital circuits.Statisticallysimulated switching information, gate delays,signal arrival patterns, and signal probabilities are consideredin reducing the switching activity-capacitance products.Power reduction up to 45.4% (acerage 12.4%) is achieved,with considerable improvements in area and delay, in pre-optimizedbenchamarks.Also the effect of transformationson the random pattern testability of the circuits is studied.
Visualizing dynamic software system information through high-level models
Authors: Robert J. Walker, Gail C. Murphy, Bjorn Freeman-Benson, Darin Wright, Darin Swanson, Jeremy Isaak
Venue: ACM SIGPLAN Notices (1998)

Dynamic information collected as a software system executes can help software engineers perform some tasks on a system more effectively. To interpret the sizable amount of data generated from a system's execution, engineers require tool support. We have developed an off-line, flexible approach for visualizing the operation of an object-oriented system at the architectural level. This approach complements and extends existing profiling and visualization approaches available to engineers attempting to utilize dynamic information. In this paper, we describe the technique and discuss preliminary qualitative studies into its usefulness and usability. These studies were undertaken in the context of performance tuning tasks.
Partial evaluation and separate compilation
Authors: Rogardt Heldal, John Hughes
Venue: Proceedings of the 1997 ACM SIGPLAN symposium on Partial evaluation and semantics-based program manipulation (1997)

Hitherto all partial evaluators have processed a complete program to produce a complete residual program. We are interested in treating programs as collections of modules which can be processed independently: 'separate partial evaluation', so to speak. In this paper we still assume that the original program is processed in its entirety, but we show how to specialise it to the static data bit-by-bit, generating a different module for each bit. When the program to be specialised is an interpreter, this corresponds to specialising it to one module of its object language at a time: each module of the object language gives rise to one module of the residual program.
MRE: a flexible approach to multi-resolution modeling
Authors: Anand Natrajan, Paul F. Reynolds,  Jr., Sudhir Srinivasan
Venue: ACM SIGSIM Simulation Digest (1997)

Multi-resolution representation of simulated entities is considered essential for a growing portion of distributed simulations. Heretofore, modelers have represented entites at just one level of resolution, or have represented concurrent representations in an inconsistent manner. We address the question of the cost of maintaining multiple, concurrent representations. We present a brief overview of our concept of a Multiple Resolution Entity (MRE) and Attribute Dependency Graph (ADG) both originally described elsewhere, and then compare simulation and consistency costs of some approaches, including our own MRE/ADG-based approach, to multi-resolution modeling. The cost analysis presented here is the first known analysis of its type, and will provide a basis for simulation designers to determine the best, and most cost-effective approach to supporting simulation of entities at different levels of resolution concurrently.
Further empirical studies of test effectiveness
Authors: Phyllis G. Frankl, Oleg Iakounenko
Venue: ACM SIGSOFT Software Engineering Notes (1998)

This paper reports on an empirical evaluation of the fault-detecting ability of two white-box software testing techniques: decision coverage (branch testing) and the all-uses data flow testing criterion. Each subject program was tested using a very large number of randomly generated test sets. For each test set, the extent to which it satisfied the given testing criterion was measured and it was determined whether or not the test set detected a program fault. These data were used to explore the relationship between the coverage achieved by test sets and the likelihood that they will detect a fault.Previous experiments of this nature have used relatively small subject programs and/or have used programs with seeded faults. In contrast, the subjects used here were eight versions of an antenna configuration program written for the European Space Agency, each consisting of over 10,000 lines of C code.For each of the subject programs studied, the likelihood of detecting a fault increased sharply as very high coverage levels were reached. Thus, this data supports the belief that these testing techniques can be more effective than random testing. However, the magnitudes of the increases were rather inconsistent and it was difficult to achieve high coverage levels.
Extraction of Logical Rules from Neural Networks
Authors: Włodzisław Duch, Rafał Adamczak, Krzysztof Grąbczewski
Venue: Neural Processing Letters (1998)

Three neural-based methods for extraction of logical rules from data are presented. These methods facilitate conversion of graded response neural networks into networks performing logical functions. MLP2LN method tries to convert a standard MLP into a network performing logical operations (LN). C-MLP2LN is a constructive algorithm creating such MLP networks. Logical interpretation is assured by adding constraints to the cost function, forcing the weights to &plusmn;1 or 0. Skeletal networks emerge ensuring that a minimal number of logical rules are found. In both methods rules covering many training examples are generated before more specific rules covering exceptions. The third method, FSM2LN, is based on the probability density estimation. Several examples of performance of these methods are presented.