ppxscal/embedding_network huggingface dataset:
Sequential Quadratic Programming Methods for Large-Scale Problems
Authors: Walter Murray
Venue: Computational Optimization and Applications (1997)

Sequential quadratic (SQP) programming methods are the method of choice when solving small or medium-sized problems. Since they are complex methods they are difficult (but not impossible) to adapt to solve large-scale problems. We start by discussing the difficulties that need to be addressed and then describe some general ideas that may be used to resolve these difficulties. A number of SQP codes have been written to solve specific applications and there is a general purposed SQP code called SNOPT, which is intended for general applications of a particular type. These are described briefly together with the ideas on which they are based. Finally we discuss new work on developing SQP methods using explicit second derivatives.
Partially-dependent functional decomposition with applications in FPGA synthesis and mapping
Authors: Jason Cong, Yean-Yow Hwang
Venue: Proceedings of the 1997 ACM fifth international symposium on Field-programmable gate arrays (1997)

In this paper, we give a necessary and sufficient condition for the existence of partially-dependent functional decomposition and develop new algorithms to compute such decompositions. We apply our method to the synthesis and mapping for Xilinx XC4000 FPGA's which contain non-uniform sizes of LUT's in its architecture. We develop a new mapping algorithm named PDDMAP which uses CLB's to cover nodes on critical paths for depth minimization and uses LUT's to cover non-critical nodes for area minimization. On average, PDDMAP is able to reduce the depth by 13%with only 1% of increase in area comparing to the results by FlowMap followed by a CLB generation procedure match_4k. We also develop a post-mapping procedure named PDDSYN which resynthesizes mapping solutionsto reduce the mapping area. On average, PDDSYN is able to improve PDDMAP mapping solutions by 5% in depth and 7% in CLB count, and achieves 8% smaller depth and 11% fewer CLB count comparing to FlowSyn followed by match-4k.
Digital image indexing and retrieval by content using the fractal transform for multimedia databases
Authors: Jean Michel Marie-Julie, Hassane Essafi
Venue: Proceedings of the IEEE international forum on Research and technology advances in digital libraries (1997)

Digital image database represent huge amount of data, automatic indexing and content base retrieval are crucial factors. Content base retrieval requests specific indexing techniques allowing to deal with efficient data representations (reduced amount of data and adapted to content base retrieval) in order to avoid prohibitive low level process time on queries. We present a method consisting in building an "iconic" level image representation preserving the semantic, allowing to process content base retrieval and to reconstruct the image. This representation consists in a set of function parameters. It is a semantic preserving compression built by using a dedicated Fractal compress scheme. To search patterns in an huge set of images, a specific algorithm allows to use this "iconic" representation as an index. It works entirely in the Fractal transform parameter space of both image and pattern, to obtain performances compatible with an interactive search. The research engine uses both textures and edges of the pattern. The pattern can be present in the image with different orientations and/or scales by using a multiresolution Fractal representation of the pattern. This method allows to retrieve in 3 seconds a 64 x 64 pixels pattern in an 100 images (512 x 512 pixels) database, on a SUN Sparc 20 workstation. It can be combined with other indexing and retrieval techniques, such as textual annotation.
Summary cache: a scalable wide-area Web cache sharing protocol
Authors: Li Fan, Pei Cao, Jussara Almeida, Andrei Z. Broder
Venue: ACM SIGCOMM Computer Communication Review (1998)

The sharing of caches among Web proxies is an important technique to reduce Web traffic and alleviate network bottlenecks. Nevertheless it is not widely deployed due to the overhead of existing protocols. In this paper we propose a new protocol called "Summary Cache"; each proxy keeps a summary of the URLs of cached documents of each participating proxy and checks these summaries for potential hits before sending any queries. Two factors contribute to the low overhead: the summaries are updated only periodically, and the summary representations are economical --- as low as 8 bits per entry. Using trace-driven simulations and a prototype implementation, we show that compared to the existing Internet Cache Protocol (ICP), Summary Cache reduces the number of inter-cache messages by a factor of 25 to 60, reduces the bandwidth consumption by over 50%, and eliminates between 30% to 95% of the CPU overhead, while at the same time maintaining almost the same hit ratio as ICP. Hence Summary Cache enables cache sharing among a large number of proxies.
Dynamics of random early detection
Authors: Dong Lin, Robert Morris
Venue: ACM SIGCOMM Computer Communication Review (1997)

In this paper we evaluate the effectiveness of Random Early Detection (RED) over traffic types categorized as non-adaptive, fragile and robust, according to their responses to congestion. We point out that RED allows unfair bandwidth sharing when a mixture of the three traffic types shares a link. This unfairness is caused by the fact that at any given time RED imposes the same loss rate on all flows, regardless of their bandwidths.We propose Fair Random Early Drop (FRED), a modified version of RED. FRED uses per-active-flow accounting to impose on each flow a loss rate that depends on the flow's buffer use.We show that FRED provides better protection than RED for adaptive (fragile and robust) flows. In addition, FRED is able to isolate non-adaptive greedy traffic more effectively. Finally, we present a "two-packet-buffer" gateway mechanism to support a large number of flows without incurring additional queueing delays inside the network. These improvements are demonstrated by simulations of TCP and UDP traffic.FRED does not make any assumptions about queueing architecture; it will work with a FIFO gateway. FRED's per-active-flow accounting uses memory in proportion to the total number of buffers used: a FRED gateway maintains state only for flows for which it has packets buffered, not for all flows that traverse the gateway.
Self-applicable partial evaluation for the pi-calculus
Authors: Marc Gengler, Matthieu Martel
Venue: Proceedings of the 1997 ACM SIGPLAN symposium on Partial evaluation and semantics-based program manipulation (1997)

In this paper, we are interested in self-applicable partial evaluation for the pi-calculus, a language which models the concurrent behavior of communicating processes. We use the classic three-steps methodology. First, we write a meta-interpreter for the language. Second, we introduce an abstract analysis that determines which operations (communications) can be executed at compile-time. The notion of well-annotatedness of terms is defined. Finally, we exhibit the self-applicable partial evaluator which is applied to well-annotated terms, and we prove its correctness with respect to the interpreter. This approach is compatible with Futamura's projections. Proofs of correctness are baaed on the notion of weak reduction equivalence.
Queue management for explicit rate based congestion control
Authors: Qingming Ma, K. K. Ramakrishnan
Venue: Proceedings of the 1997 ACM SIGMETRICS international conference on Measurement and modeling of computer systems (1997)

Rate based congestion control has been considered desirable, both to deal with the high bandwidth-delay products of today's high speed networks, and to match the needs of emerging multimedia applications. Explicit rate control achieves low loss because sources transmit smoothly at a rate adjusted through feedback to be within the capacity of the resources in the network. However, large feedback delays, presence of higher priority traffic, and varying transient situations make it difficult to ensure feasibility (i.e., keep the aggregate arrival rate below the bottleneck resource's capacity) while also maintaining high resource utilization. These conditions along with the "fast start" desired by data applications often result in substantial queue buildups.We describe a scheme that manages the queue buildup at a switch even under the most aggressive patterns of sources, in the context of the Explicit Rate option for the Available Bit Rate (ABR) congestion control scheme. A switch observes the buildup of its queue, and uses it to reduce the portion of the link capacity allocated to sources bottlenecked at that link. We use the concept of a "virtual" queue, which tracks the amount of queue that has been "reduced", but has not yet taken effect at the switch. We take advantage of the natural timing of "resource management" (RM) cells transmitted by sources. The scheme is elegant in that it is simple, and we show that it reduces the queue buildup, in some cases, by more than two orders of magnitude and the queue size remains around a desired target. It maintains max-min fairness even when the queue is being drained. The scheme is scalable, and is as responsive as can be expected: within the constraints of the feedback delay. Finally, no changes are needed to the ATM Forum defined source/destination policies.
Microprogramming heritage of RISC design
Authors: Liwen Shih
Venue: Proceedings of the 23rd annual workshop and symposium on Microprogramming and microarchitecture (1990)

Technology impact brings Reduced Instruction Set Computer (RISC) design approach back to the stage of computer architecture evolution. While RISC architecture grab attention by their flying instruction rates, this paper summarizes the current design of micro-architectures and analyzes the tradeoffs between RISC approach and Microprogramming approach especially on the vertical migration among hardware, firmware, compilation and software. RISCs' simplicity is contrasted by the regularity of microprogrammed control. The RISC design incentives are categorized into three perspectives, namely, technology-driven, application-driven, and performance-driven. Traditional firmware migration approaches are reviewed and related to RISC design philosophy as well as Writable Instruction Set Computer (WISC) concept. Research such as Firmware Migration candidates selection can be applied to RISC instruction set design. Similarly, micro-code generation and compaction research can be used to construct the smart, optimizing RISC compiler. Horizontal microcode approach is interpreted as the Very Long Instruction Word (VLIW) architecture. Incorporating in the discussion about new design trends affected by GaAs, memory technology, and super-computing a clue for the direction of future-proof micro-architecture and microprogramming is projected.
Application of Artificial Neural Networks to Medical Image Pattern Recognition: Detection of Clustered Microcalcifications on Mammograms and Lung Cancer on Chest Radiographs
Authors: Shih-Chung B. Lo, Jyh-Shyan J. Lin, Matthew T. Freedman, Seong K. Mun
Venue: Journal of VLSI Signal Processing Systems (1998)

Three neural network models were employed to evaluate their performances in the recognition of medical image patterns associated with lung cancer and breast cancer in radiography. The first method was a pattern match neural network. The second was a conventional backpropagation neural network. The third method was a backpropagation trained neocognitron in which the signal propagation is operated with the convolution calculation from one layer to the next. In the convolution neural network (CNN) experiment, several output association methods and trainer imposed driving functions in conjunction with the convolution neural network are proposed for general medical image pattern recognition. An unconventional method of applying rotation and shift invariance is also used to enhance the performance of the neural nets.We have tested these methods for the detection of microcalcifications on mammograms and lung nodules on chest radiographs. Pre-scan methods were previously described in our early publications. The artificial neural networks act as final detection classifiers to determine if a disease pattern is presented on the suspected image area. We found that the convolution neural network, which internally performs feature extraction and classification, achieves the best performance among the three neural network models. These results show that some processing associated with disease feature extraction is a necessary step before a classifier can make an accurate determination.
Computing Linear Codes and Unitals
Authors: David B. Jaffe, Vladimir D. Tonchev
Venue: Designs, Codes and Cryptography (1998)

The 2-rank of any 2-(28,4,1) design (unital on 28 points) is known to be between 19 and 27. It is shown by the enumeration and analysis of certain binary linear codes that there are no unitals of 2-rank 20, and that there are exactly 4 isomorphism classes of unitals of 2-rank 21. Combined with previous results, this completes the classification of unitals on 28 points of 2-rank less than 22.
Deterrence, Reputations, and Competitive Cognition
Authors: Bruce H. Clark, David B. Montgomery
Venue: Management Science (1998)

This study examines an aspect of competitive interactions that has attracted increasing research attention: the relationship between deterrence and competitive reputations. We build a conceptual model of the antecedents and consequences of a firm's reputation for being a credible defender of its markets. Theory and limited empirical evidence suggests a firm with this reputation should deter competitive attacks against it. We explore how a manager's competitive cognition about her opponents' (1) patterns of activity in the marketplace and (2) previous success can lead her to perceive a competitor as a credible defender. We test the framework using MBA students in a quasi-field setting, the Markstrat2 simulation game. The results of this study suggest that reputation deters attack only when the potential attacker considers the target firm a minor competitor. Managers consider defenders that have previously been successful as credible defenders of their markets. They also weigh consistency of activity relative to industry average in making inferences about credibility. The study indicates that the deterrence-reputation link is more complex than previous theory and evidence might imply, and suggests considerable promise for a psychological approach to examining competitive interactions.
Analysis of Metastable Operation in a CMOS Dynamic D-Latch
Authors: J. Juan-Chico, M. J. Bellido, A. J. Acosta, M. Valencia, J. L. Huertas
Venue: Analog Integrated Circuits and Signal Processing (1997)

Nowadays, metastability is becoming a serious problem in high-performance VLSI design, mainly due to the relatively-high probability of error when a bistable circuit operates at high frequencies. As far as we know, there is not any work published that justifies and formally characterizes metastable behavior in dynamic latches. With current technologies, dynamic latches are widely used in high-performance VLSI circuits, mainly due to their lower cost and higher operation speed than static latches. In this work, we demonstrate that dynamic memory cells present an anomalous behavior referred to as metastable operation with characteristics similar to those of static latches. We perform a suitable generalization of metastability to the dynamic case, applying it to a CMOS dynamic D-latch. A theoretical model will be proposed, allowing the quantification of metastability, and it will be validated through electric simulation with HSPICE. After that, we have compared the metastable behavior of the dynamic latch with its static counterpart, obtaining results about the characteristic parameters of metastability and the Mean Time Between Failures (MTBF) for both kinds of bistable circuits. These results have allowed us to conclude that, unlike metastability windows in static latches, a clearly defined input interval exists which produces an infinite resolution time. Regarding MTBF, the dynamic latch presents a very low MTBF value compared to the static latch. These results show that dynamic latches should not be used in those circuits where the risk of asynchronism between clock and data signals is not negligible.
Algorithm 781: generating Hilbert's space-filling curve by recursion
Authors: Greg Breinholt, Christoph Schierz
Venue: ACM Transactions on Mathematical Software (TOMS) (1998)

An efficient algorithm for the generation of Hilbert's space-filling curve is given. The algorithm implements a recursive procedure that involves simple integer operations and quickly converges to the set of points that make the Hilbert curve. The algorithm is elegant, short, and considerably easier to implement than previous recursive and nonrecursive algorithms and can be efficiently implemented in all programming languages that have integer operations and allow recursion. The fundamental Hilbert shape (a line joining the four corners of a square) is represented by two variables with values of either 0 or 1. This coding technique could be successfully applied to the generation of other regular space-filling curves, such as the Peano curve.
The marriage of effects and monads
Authors: Philip Wadler
Venue: Proceedings of the third ACM SIGPLAN international conference on Functional programming (1998)

Gifford and others proposed an effect typing discipline to delimit the scope of computational effects within a program, while Moggi and others proposed monads for much the same purpose. Here we marry effects to monads, uniting two previously separate lines of research. In particular, we show that the type, region, and effect system of Talpin and Jouvelot carries over directly to an analogous system for monads, including a type and effect reconstruction algorithm. The same technique should allow one to transpose any effect systems into a corresponding monad system.
The Random Subspace Method for Constructing Decision Forests
Authors: Tin Kam Ho
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (1998)

Much of previous attention on decision trees focuses on the splitting criteria and optimization of tree sizes. The dilemma between overfitting and achieving maximum accuracy is seldom resolved. A method to construct a decision tree based classifier is proposed that maintains highest accuracy on training data and improves on generalization accuracy as it grows in complexity. The classifier consists of multiple trees constructed systematically by pseudorandomly selecting subsets of components of the feature vector, that is, trees constructed in randomly chosen subspaces. The subspace method is compared to single-tree classifiers and other forest construction methods by experiments on publicly available datasets, where the method's superiority is demonstrated. We also discuss independence between trees in a forest and relate that to the combined classification accuracy.
Configuration Controllability of Simple Mechanical Control Systems
Authors: Andrew D. Lewis, Richard M. Murray
Venue: SIAM Journal on Control and Optimization (1997)

In this paper we present a definition of "configuration controllability" for mechanical systems whose Lagrangian is kinetic energy with respect to a Riemannian metric minus potential energy. A computable test for this new version of controllability is derived. This condition involves an object which we call the symmetric product. Of particular interest is a definition of "equilibrium controllability" for which we are able to derive computable sufficient conditions. Examples illustrate the theory.
Secure Identification Documents Via Pattern Recognition and Public-Key Cryptography
Authors: Lawrence O'Gorman, Irina Rabinovich
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (1998)

Personal identification documents, such as photo ID cards, are being used increasingly for such activities as financial transactions; entry into restricted areas; and personal verification for medical, government, and commercial (in particular, airlines) services. With this trend, there is also the increasing trend toward counterfeiting these documents for illegal gain. We present an approach to authenticating photo-ID documents that relies on pattern recognition and public-key cryptography and has security advantages over physical mechanisms that currently safeguard cards, such as optical laminates and holograms. The pattern-recognition component of this approach is based on a photo signature that is a concise representation of the photo image on the document. This photo signature is stored in a database for remote authentication or in encrypted form on the card for stand-alone authentication. Verification of the ID document entails scanning both the photo image and a machine-readable form of the text information, determining the photo signature, and comparing this information against the reference. In this paper, we describe the method and present results of testing a large database of images for photo-signature match in the presence of noise.
Possible and Impossible Self-Stabilizing Digital ClockSynchronization in General Graphs
Authors: Shlomi Dolev
Venue: Real-Time Systems (1997)

We study digital clock synchronization for multiprocessor systems, where processors are triggered by a common clock pulse and communicate with others via shared memory. A self-stabilizing digital clock synchronization protocol for systems with a general communication graph is presented. The protocol can commence in an arbitrary non-consistent system state and converges to a legitimate state in which the clocks are synchronized and incremented by one in every subsequent pulse.To enhance the fault-tolerance of our protocol, we allow that during and following convergence processors may stop operating. Crash failures may partition the communication graph into several connected components. Our protocol synchronizes the clocks of the processors in every such connected component. For the case in which faulty processors can exhibit Byzantine behavior, we prove that there is no digital clock synchronization protocol that tolerates even one single faulty processor.
k-Pairwise Cluster Fault Tolerant Routing in Hypercubes
Authors: Qian-Ping Gu, Shietung Peng
Venue: IEEE Transactions on Computers (1997)

In this paper, we introduce a general fault tolerant routing problem, cluster fault tolerant routing, which is a natural extension of the well studied node fault tolerant routing problem. A cluster is a connected subgraph of a graph G, and a cluster is faulty if all nodes in it are faulty. In cluster fault tolerant routing (abbreviated as CFT routing), we are interested in the number of faulty clusters and the size of the clusters that an interconnection network can tolerate for certain routing problems. As a case study, we investigate the following k-pairwise CFT routing in n-dimensional hypercubes Hn: Given a set of faulty clusters and k distinct nonfaulty node pairs (s1, t1), ..., (sk, tk) in Hn, find k fault-free node-disjoint paths si¿ti, 1 ¿i¿k. We show that Hn can tolerate n¿ 2 faulty clusters of diameter one, plus one faulty node for the k-pairwise CFT routing with k = 1. For n¿ 4 and $2 \le k \le \lceil n/2 \rceil,$ we prove that Hn can tolerate n¿ 2k + 1 faulty clusters of diameter one for the k-pairwise CFT routing. We also give an O(kn log n) time algorithm which finds the k paths for the mentioned problem. Our algorithm implies an O(n2 log n) time algorithm for the k-pairwise node-disjoint paths problem in Hn, which improves the previous result of O(n3 log n).