ppxscal/embedding_network huggingface dataset:
Geometric Structure Analysis of Document Images: A Knowledge-Based Approach
Authors: Kyong-Ho Lee, Yoon-Chul Choy, Sung-Bae Cho
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (2000)

Geometric structure analysis is a prerequisite to create electronic documents from logical components extracted from document images. This paper presents a knowledge-based method for sophisticated geometric structure analysis of technical journal pages. The proposed knowledge base encodes geometric characteristics that are not only common in technical journals but also publication-specific in the form of rules. The method takes the hybrid of top-down and bottom-up techniques and consists of two phases: region segmentation and identification. Generally, the result of the segmentation process does not have a one-to-one matching with composite layout components. Therefore, the proposed method identifies nontext objects, such as images, drawings, and tables, as well as text objects, such as text lines and equations, by splitting or grouping segmented regions into composite layout components. Experimental results with 372 images scanned from the IEEE Transactions on Pattern Analysis and Machine Intelligence show that the proposed method has performed geometric structure analysis successfully on more than 99 percent of the test images, resulting in impressive performance compared with previous works.
High-Speed Booth Encoded Parallel Multiplier Design
Authors: Wen-Chang Yeh, Chein-Wei Jen
Venue: IEEE Transactions on Computers (2000)

This paper presents a design methodology for high-speed Booth encoded parallel multiplier. For partial product generation, we propose a new modified Booth encoding (MBE) scheme to improve the performance of traditional MBE schemes. For final addition, a new algorithm is developed to construct multiple-level conditional-sum adder (MLCSMA). The proposed algorithm can optimize final adder according to the given cell properties and input delay profile. Compared with a binary tree-based conditional-sum adder, the speed performance improvement is up to 25 percent. On average, the design developed herein reduces the total delay by 8 percent for parallel multiplier. The whole design has been verified by gate level simulation.
Value-based clock gating and operation packing: dynamic strategies for improving processor power and performance
Authors: David Brooks, Margaret Martonosi
Venue: ACM Transactions on Computer Systems (TOCS) (2000)

The large address space needs of many current applications have pushed processor designs toward 64-bit word widths. Although full 64-bit addresses and operations are indeed sometimes needed, arithmetic operations on much smaller quantities are still more common. In fact, another instruction set trend has been the introduction of instructions geared toward subword operations on 16-bit quantities. For examples, most major processors now include instruction set support for multimedia operations allowing parallel execution of several subword operations in the same ALU. This article presents our observations demonstrating that operations on &ldquo;narrow-width&rdquo; quantities are common not only in multimedia codes, but also in more general workloads. In fact, across the SPECint95 benchmarks, over half the integer operation executions require 16 bits or less. Based on this data, we propose two hardware mechanisms that dynamically recognize and capitalize on these narrow-width operations. The first, power-oriented optimization reduces processor power consumption by using operand-value-based clock gating to turn off portions of arithmetic units that will be unused by narrow-width operations. This optimization results in a 45%-60% reduction in the integer unit's power consumption for the SPECint95 and MediaBench benchmark suites. Applying this optimization to SPECfp95 benchmarks results in slightly smaller power reductions, but still seems warranted. These reductions in integer unit power consumption equate to a 5%-10% full-chip power savings. Our second, performance-oriented optimization improves processor performance by packing together narrow-width operations so that they share a single arithmetic unit. Conceptually similar to a dynamic form of MMX, this optimization offers speedups of 4.3%-6.2% for SPECint95 and 8.0%-10.4% for MediaBench. Overall, these optimizations highlight an increasing opportunity for value-based optimizations to improve both power and performance in current microprocessors.
Completeness in formal specification language design for process-control systems
Authors: E.-R. Olderog, A. P. Ravn
Venue: Proceedings of the third workshop on Formal methods in software practice (2000)

We show how UML class diagrams can be used to document design by refinement in the early design stages. This is illustrated by an example from the area of embedded real-time and hybrid systems. A precise semantics is given for the UML class diagrams by translation to the Z schema calculus.
A new partitioning scheme for improvement of image computation
Authors: Christoph Meinel, Christian Stangier
Venue: Proceedings of the 2001 Asia and South Pacific Design Automation Conference (2001)

Image computation is the core operation for optimization and formal verification of sequential systems like controllers or protocols. State exploration techniques based on OBDDs use a partitioned representation of the transition relation to keep the OBDD-sizes manageable. This paper presents a new approach that significantly increases the quality of the partitioning of the transition relation of finite state machines. The heuristic has been successfully applied to reachability analysis and symbolic model checking of real life designs, resulting in a significant reduction in CPU time as well as in memory consumption.
The design and implementation of the open Ravenscar kernel
Authors: Juan A. de la Puente, Juan Zamorano, José Ruiz, Ramón Fernández, Rodrigo García
Venue: ACM SIGAda Ada Letters (2001)

This paper describes the design and implementation of Open Ravenscar Kernel (ORK), an open-source real-time kernel of reduced size and complexity, for which users can seek certification for mission-critical space applications. The kernel supports Ada 95 tasking on an ERC32 (SPARC v7) architecture in an efficient and compact way. It is closely integrated with the GNAT runtime library and other tools.
Small representation of line arrangements
Authors: David P. Dobkin, Ayellet Tal
Venue: Proceedings of the seventeenth annual symposium on Computational geometry (2001)

In this video we illustrate a technique for lossy compression of arran gements. The video also demonstrates the visualization techniques that facilitated the research. Detailed description of the algorithm appears in the full paper in this proceedings~\cite{DT-01}.
Transparent Queries: investigation users' mental models of search engines
Authors: Jack Muramatsu, Wanda Pratt
Venue: Proceedings of the 24th annual international ACM SIGIR conference on Research and development in information retrieval (2001)

Typically, commercial Web search engines provide very little feedback to the user concerning how a particular query is processed and interpreted. Specifically, they apply key query transformations without the users knowledge. Although these transformations have a pronounced effect on query results, users have very few resources for recognizing their existence and understanding their practical importance. We conducted a user study to gain a better understanding of users knowledge of and reactions to the operation of several query transformations that web search engines automatically employ. Additionally, we developed and evaluated Transparent Queries, a software system designed to provide users with lightweight feedback about opaque query transformations. The results of the study suggest that users do indeed have difficulties understanding the operation of query transformations without additional assistance. Finally, although transparency is helpful and valuable, interfaces that allow direct control of query transformations might ultimately be more helpful for end-users.
A semantics for dynamic ceiling priorities in Ada
Authors: Jorge Real, Albert Llamosí, Alfons Crespo
Venue: Proceedings of the 10th international workshop on Real-time Ada workshop (2001)

Several arguments have been given to justify the exclusion of dynamic ceiling priorities for protected objects in Ada. These arguments center on semantic complexity, the risks that can be derived from an erroneous usage of dynamic ceilings, and efficiency. But dynamic ceilings are very convenient for multi-moded systems and to dynamically adapting existing program libraries containing protected objects to new applications. This paper proposes a semantics for dynamic ceilings that does not add complexity to the language semantics or inefficiency to the run time system.
Shape Reconstruction of 3D Bilaterally Symmetric Surfaces
Authors: Ilan Shimshoni, Yael Moses, Michael Lindenbaum
Venue: International Journal of Computer Vision (2000)

The paper presents a new approach for shape recovery based on integrating geometric and photometric information. We consider 3D bilaterally symmetric objects, that is, objects which are symmetric with respect to a plane (e.g., faces), and their reconstruction from a single image. Both the viewpoint and the illumination are not necessarily frontal. Furthermore, no correspondence between symmetric points is required.The basic idea is that an image taken from a general, non frontal viewpoint, under non-frontal illumination can be regarded as a pair of images. Each image of the pair is one half of the object, taken from different viewing positions and with different lighting directions. Thus, one-image-variants of geometric stereo and of photometric stereo can be used. Unlike the separate invocation of these approaches, which require point correspondence between the two images, we show that integrating the photometric and geometric information suffice to yield a dense correspondence between pairs of symmetric points, and as a result, a dense shape recovery of the object. Furthermore, the unknown lighting and viewing parameters, are also recovered in this process.Unknown distant point light source, Lambertian surfaces, unknown constant albedo, and weak perspective projection are assumed. The method has been implemented and tested experimentally on simulated and real data.
A structural EM algorithm for phylogenetic inference
Authors: Nir Friedman, Matan Ninio, Itsik Pe'er, Tal Pupko
Venue: Proceedings of the fifth annual international conference on Computational biology (2001)

A central task in the study of evolution is the reconstruction of a phylogenetic tree from sequences of current-day taxa. A well supported approach to tree reconstruction performs maximum likelihood (ML) analysis. Unfortunately, searching for the maximum likelihood phylogenetic tree is computationally expensive. In this paper, we describe a new algorithm that uses Structural-EM for learning maximum likelihood trees. This algorithm is similar to the standard EM method for estimating branch lengths, except that during iterations of this algorithms the topology is improved as well as the branch length. The algorithm performs iterations of two steps. In the E-Step, we use the current tree topology and branch lengths to compute expected sufficient statistics, which summarize the data. In the M-Step, we search for a topology that maximizes the likelihood with respect to these expected sufficient statistics. As we show, searching for better topologies inside the M-step can be done efficiently, as opposed to standard search over topologies. We prove that each iteration of this procedure increases the likelihood of the topology, and thus the procedure must converge. We evaluate our new algorithm on both synthetic and real sequence data, and show that it is both dramatically faster and finds more plausible trees than standard search for maximum likelihood phylogenies.
A note on Cheney's nonrecursive list-compacting algorithm
Authors: David C. Walden
Venue: Communications of the ACM (1972)

Cheney's list-compacting algorithm [1] goes into an infinite loop when it traces a circular list consisting exclusively of non-items. While it may be reasonable to say that such lists should not exist, it would be very difficult to legislate out of existence programs which illegally create such lists because of bugs, and it would not do for the garbage collector to break down in this instance.
A generalized control structure and its formal definition
Authors: David Lorge Parnas
Venue: Communications of the ACM (1983)

A new programming language control structure as well as an improved approach to a formal definition of programming languages are presented. The control structure can replace both iteration and conditional structures. Because it is a semantic generalization of those structures, a single statement using the new control structure can implement the functions of loops, conditionals, and also programs that would require several conventional constructs. As a consequence of this increased capability, it is possible to write algorithms that are simpler, more efficient, and more clearly correct than those that can be written with earlier structured-programming control structures. In order to provide a precise definition of the new constructs, a new version of relational semantics, called LD-relations is presented. An algebra of these relations is developed and used to define the meaning of the new constructs. A short discussion of program development and the history of control structures is included.
A note on the efficiency of a LISP computation in a paged machine
Authors: Daniel G. Bobrow, Daniel L. Murphy
Venue: Communications of the ACM (1968)

The problem of the use of two levels of storage for programs is explored in the context of a LISP system which uses core memory as a buffer for a large virtual memory stored on a drum. Details of timing are given for one particular problem.
Right brother trees
Authors: Th. Ottmann, H. W. Six, D. Wood
Venue: Communications of the ACM (1978)

Insertion and deletion algorithms are provided for the class of right (or one-sided) brother trees which have O (log n) performance. The importance of these results stems from the close relationship of right brother trees to one-sided height-balanced trees which have an insertion algorithm operating in O (log2 n). Further, although both insertion and deletion can be carried out in O (log n) time for right brother trees, it appears that the insertion algorithm is inherently much more difficult than the deletion algorithm&mdash;the reverse of what one usually obtains.
The Quotient Image: Class-Based Re-Rendering and Recognition with Varying Illuminations
Authors: Amnon Shashua, Tammy Riklin-Raviv
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (2001)

The paper addresses the problem of ¿class-based¿ image-based recognition and rendering with varying illumination. The rendering problem is defined as follows: Given a single input image of an object and a sample of images with varying illumination conditions of other objects of the same general class, re-render the input image to simulate new illumination conditions. The class-based recognition problem is similarly defined: Given a single image of an object in a database of images of other objects, some of them are multiply sampled under varying illumination, identify (match) any novel image of that object under varying illumination with the single image of that object in the database. We focus on Lambertian surface classes and, in particular, the class of human faces. The key result in our approach is based on a definition of an illumination invariant signature image which enables an analytic generation of the image space with varying illumination. We show that a small database of objects¿in our experiments as few as two objects¿is sufficient for generating the image space with varying illumination of any new object of the class from a single input image of that object. In many cases, the recognition results outperform by far conventional methods and the re-rendering is of remarkable quality considering the size of the database of example images and the mild preprocess required for making the algorithm work.
Object-focused interaction in collaborative virtual environments
Authors: Jon Hindmarsh, Mike Fraser, Christian Heath, Steve Benford, Chris Greenhalgh
Venue: ACM Transactions on Computer-Human Interaction (TOCHI) (2000)

This paper explores and evaluates the support for object-focused interaction provided by a desktop Collaborative Virtual Environment. An experimental &ldquo;design&rdquo; task was conducted, and video recordings of the participants' activities facilitated an observational analysis of interaction in, and through, the virtual world. Observations include: problems due to &ldquo;fragmented&rdquo; views of embodiments in relation to shared objects; participants compensating with spoken accounts of their actions; and difficulties in understanding others' perspectives. Implications and proposals for the design of CVEs drawn from these observations are: the use of semidistorted views to support peripheral awareness; more explicit or exaggerated representations of actions than are provided by pseudohumanoid avatars; and navigation techniques that are sensitive to the actions of others. The paper also presents some examples of the ways in which these proposals might be realized.
On a class of iteration formulas and some historical notes
Authors: J. F. Traub
Venue: Communications of the ACM (1961)

The class of iteration formulas obtainable by rational approximations of &ldquo;Euler's formula&rdquo; is derived with the corresponding error estimates. Some historical notes on iterative procedures are followed by a derivation of Euler's formula with the associated error estimate in a new notation which simplifies the error estimate and suggests generalizations. The final section considers the Pad&eacute; approximants to the &ldquo;Euler polynomial&rdquo; and shows how a number of known formulas may be derived from this unified approach. There is a short discussion of the &ldquo;best&rdquo; formula.
Video summarisation based on the psychological content in the track structure
Authors: Tsuyoshi Moriyama, Masao Sakauchi
Venue: Proceedings of the 2000 ACM workshops on Multimedia (2000)

In this study, the method to summarise TV drama based on the psychological unfolding is proposed. In past researches, video summarisation has been achieved almost by way of choosing representative frames in visual track and never based on the mental side of video content. In this work, the video structure which consists of audio visual tracks (actor's utterances, BGM, background sound, effect sounds and shots) is modeled and the track-structure-based video summarization method is proposed. To extract the temporal feature patterns of the track structure correspondent with the specific psychological content, each tracks is first quantified by calculating existence ratio etc., and second the intra/inter track feature patterns are determined based on empirical knowledges. The proposed method is implemented and examined in the subjective experiment.
A theory of discrete patterns and their implementation in SNOBOL4
Authors: J. F. Gimpel
Venue: Communications of the ACM (1973)

The notion of a discrete pattern is formalized and certain properties deduced. A pattern is shown to be a generalization of a formal language. Algorithms for implementing the kinds of patterns in SNOBOL4 are given. The general approach is to create, in-so-far as possible, a bottom-up parse from a top-down specification.
A hybrid dynamic/quadratic programming algorithm for interconnect tree optimization
Authors: Y.-Y. Mo, C. C. N. Chu
Venue: Proceedings of the 2000 international conference on Computer-aided design (2001)

In this paper, we present an algorithm for delay minimization of interconnect trees by simultaneous buffer insertion/sizing and wire sizing. The algorithm integrates the quadratic programming approach to handle a wire branch [1] into the dynamic programming framework [2]. Our experimental results show that our hybrid dynamic/quadratic programming algorithm is faster, more accurate, and uses much less memory than the pure dynamic programming approach.
Model-Based Estimation of 3D Human Motion
Authors: Ioannis Kakadiaris, Dimitris Metaxas
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (2000)

This paper presents the formulations and techniques that we have developed for the three-dimensional, model-based, motion estimation of human movement from multiple cameras. Our method is based on the spatio-temporal analysis of the subject's silhouette and it has the advantage that the subject does not have to wear markers or other devices. We present tracking results from experiments involving the recovery of complex motions in the presence of significant occlusion.
Reliability and performance of hierarchical RAID with multiple controllers
Authors: Sung Hoon Baek, Bong Wan Kim, Eui Joung Joung, Chong Won Park
Venue: Proceedings of the twentieth annual ACM symposium on Principles of distributed computing (2001)

Redundant arrays of inexpensive disks (RAID) offer fault tolerance against disk failures. However a storage system having more disks suffers from less reliability and performance. A RAID architecture tolerating multiple disk failures shows severe performance degradation in comparison to the RAID Level 5 due to the complexity of implementation. We present a new RAID architecture that tolerates at least three disk failures and offers similar throughout to the RAID Level 5. We call it the hierarchical RAID, which is hierarchically composed of RAID Levels. Furthermore, we formally introduce the mean-time-to-data-loss (MTTDL) of traditional RAID and the hierarchical RAID using Markov process for detailed comparison.
Energy-Efficient Initialization Protocols for Single-Hop Radio Networks with No Collision Detection
Authors: Koji Nakano, Stephen Olariu
Venue: IEEE Transactions on Parallel and Distributed Systems (2000)

A radio network ($RN$, for short) is a distributed system consisting of $n$ radio stations. We assume that the stations are small, bulk-produced, hand-held devices running on batteries and cannot be distinguished by serial or manufacturing number. Since recharging batteries may not be possible while on mission, we are interested in designing protocols that are highly energy-efficient. The initialization problem is to assign each of the $n$ stations in the RN a unique ID. The initialization problem is nontrivial since the stations are assumed to be indistinguishable. The problem is fundamental, since practically all communication protocols for $RN$s proceed under the assumption that the RN has been initialized in advance. The main contribution of this work is to propose energy-efficient randomized initialization protocols for single-hop $RN$s lacking collision detection capabilities. First, we show that if the number $n$ of stations is known beforehand, the single-channel $RN$ can be initialized by a protocol that terminates, with probability exceeding $1 - {\frac{1}{n}}$, in $O(n)$ time slots, with no station being awake for more than $O(\log \log n)$ time slots. We then go on to address the multichannel case and show that if $k$, $(k \geq 1)$, channels are available, an n-station $RN$ can be initialized, with probability exceeding $1 - {\frac{1}{n}}$, in $O({n\over k}+\log n)$ time slots, with no station being awake for more than $O(\log\log n)$ time slots.