ppxscal/embedding_network huggingface dataset:
A framework for implementing hypothetical queries
Authors: Timothy Griffin, Richard Hull
Venue: Proceedings of the 1997 ACM SIGMOD international conference on Management of data (1997)

Previous approaches to supporting hypothetical queries have been &ldquo;eager&rdquo;: some representation of the hypothetical state (or the corresponding delta) is materialized, and query evaluation is filtered through that representation. This paper develops a framework for evaluating hypothetical queries using a &ldquo;lazy&rdquo; approach, or using a hybrid of eager and lazy approaches. We focus on queries having the form &ldquo;Q when {{U}}&rdquo; where Q is a relational algebra query and U is an update expression. The value assigned to this query in state DB is the value that Q would return in the state resulting from executing U on DB. Nesting of the keyword when is permitted, and U may involve a sequence of several atomic updates. We present an equational theory for queries involving when that can be used as a basis for optimization. This theory is very different from traditional rules for the relational algebra, because the semantics of when is unlike the semantics of the algebra operators. Our theory is based on the observation that hypothetical states can be represented as substitutions, similar to those arising in functional and logic programming. Furthermore, hypothetical queries of the form Q when {{U}} can be thought of as representing the suspended application of a substitution. Using the equational theory we develop an approach to optimizing the evaluation of hypothetical queries that uses deltas in the sense of Heraclitus, and permits a range of evaluation strategies from lazy to eager.
A Note on Thin P-Polynomial and Dual-Thin Q-PolynomialSymmetric Association Schemes
Authors: Garth A. Dickie, Paul M. Terwilliger
Venue: Journal of Algebraic Combinatorics: An International Journal (1998)

Let Y denote a d-class symmetric association scheme, with d &ge; 3. We show the following: If Y admits a P-polynomial structure with intersection numbers p^h_ij and Y is 1-thin with respect to at least one vertex, then p^1_11=0 &rarr; p^i_1i=0 1 &le; i &le; - 1. If Y admits a Q-polynomial structure with Krein parameters q^h_ij, and Y is dual 1-thin with respect to at least one vertex, then q^1_11 = 0 &rarr; q ^i_1i = 01 &le; i &le; d-1.
Resource-sensitive profile-directed data flow analysis for code optimization
Authors: Rajiv Gupta, David A. Berson, Jesse Z. Fang
Venue: Proceedings of the 30th annual ACM/IEEE international symposium on Microarchitecture (1997)

Instruction schedulers employ code motion as a means of instruction reordering to enable scheduling of instructions at points where the resources required for their execution are available. In addition, driven by the profiling data, schedulers take advantage of predication and speculation for aggressive code motion across conditional branches. Optimization algorithms for partial dead code elimination (PDE) and partial redundancy elimination (PRE) employ code sinking and hoisting to enable optimization. However, unlike instruction scheduling, these optimization algorithms are unaware of resource availability and are incapable of exploiting profiling information, speculation, and predication. In this paper we develop data flow algorithms for performing the above optimizations with the following characteristics: (i) opportunities for PRE and PDE enabled by hoisting and sinking are exploited; (ii) hoisting and sinking of a code statement is driven by availability of functional unit resources; (iii) predication and speculation is incorporated to allow aggressive hoisting and sinking; and (iv) path profile information guides predication and speculation to enable optimization.
Why COBOL programmers refuse Ada
Authors: Kenneth Fussichen
Venue: Proceedings of the conference on TRI-ADA '90 (1990)

The problems associated with asking a COBOL1 programmer to learn Ada can be likened to the problems you might anticipate when an American employee is asked to learn Japanese. Significant motivation must be provided to overcome some of the obstacles. First, learning Japanese is difficult. The Japanese and English languages have no common ancestry. Second, societal values vary. Third, it is difficult to generate much interest in learning anything when its anticipated practical use is minimal. Of course, with proper motivation, anyone can learn either Japanese or Ada. In either case, the anticipated benefit must exceed the anticipated learning effort. An anticipated transfer to Tokyo could conceivably spur some interest in learning Japanese. But what could possibly motivate the COBOL programmer to learn Ada?
Simulation using GPSS/H
Authors: Robert C. Crain
Venue: Proceedings of the 28th conference on Winter simulation (1996)

GPSS/H is a tried-and-true simulation tool whose user base, both commercial and academic, continues to grow despite the presence of many "new" simulation technology trends. The process-interaction world view combines with the advanced features available in GPSS/H to make one of the most powerful and flexible tools available, capable of handling the largest simulation projects with ease, yet still providing exceptionally high performance. The following sections provide an overview of GPSS/H and its process-interaction world view, a discussion of model-building interfaces including the advantages and pitfalls of graphical modeling environments, and a summary of advanced and recently-added GPSS/H features. Finally, the special purpose simulator is discussed, along with features of GPSS/H which make it ideal for use as the engine in such a simulator.
Economic forecasting by the deterministic-adaptive method
Authors: Sergei M. Obraztsov, Dmitri V. Chelegatski, Inna N. Louneva, Alexander L. Shimkevich
Venue: Proceedings of the conference on Designing the future (1996)

Economic forecasting is of great importance when some economic mechanism is changed rapidly as in Russia nowadays. Any economic system is a deterministic-stochastic entity of great complexity. Because of this, informative models which offer the interplay of the most significant factors are inadequate for satisfactory long-term forecasting.The paper describes a forecasting procedure based on the joint use of formalized method (numerical simulation) and adaptive method (simulation with a neural network) when the model structure is formed by incoming information.A combination of forecasts selected by experts allows one to make the most likely forecast from the "fan" of probable tracks.An APL implementation of this procedure has been used for the forecasting of municipal expenditures and has brought significant economic benefits.
Fault simulation in a distributed environment
Authors: Patrick A. Duba, Rabindra K. Roy, Jacob A. Abraham, William A. Rogers
Venue: Proceedings of the 25th ACM/IEEE Design Automation Conference (1988)

Fault simulation of VLSI circuits takes considerable computing resources and there have been significant efforts to speed up the fault simulation process. This paper describes a distributed fault simulator implemented on a loosely-coupled network of general purpose computers. The techniques used result in a close to linear speedup and can be used effectively in most industrial VLSI CAD environments.
Randomized Data Structures for the Dynamic Closest-Pair Problem
Authors: Mordecai Golin, Rajeev Raman, Christian Schwarz, Michiel Smid
Venue: SIAM Journal on Computing (1998)

We describe a new randomized data structure, the sparse partition, for solving the dynamic closest-pair problem. Using this data structure the closest pair of a set of n points in D-dimensional space, for any fixed D, can be found in constant time. If a frame containing all the points is known in advance, and if the floor function is available at unit cost, then the data structure supports insertions into and deletions from the set in expected O(log n) time and requires expected O(n) space. This method is more efficient than any deterministic algorithm for solving the problem in dimension D > 1. The data structure can be modified to run in O(log2 n) expected time per update in the algebraic computation tree model. Even this version is more efficient than the best currently known deterministic algorithm for D > 2. Both results assume that the sequence of updates is not determined in any way by the random choices made by the algorithm.
Optimal aspect ratios of building blocks in VLSI
Authors: Shmuel Wimer, Israel Koren, Israel Cederbaum
Venue: Proceedings of the 25th ACM/IEEE Design Automation Conference (1988)

The building blocks in a given floorplan may have several possible physical implementations yielding different layouts. This paper discusses the problem of selecting an optimal implementation for each building block so that the area of the final layout is minimized. A polynomial algorithm that solves this problem for slicing floorplans was presented elsewhere, and it has been proved that for general (non-slicing) floorplans the problem is NP-complete. We suggest a branch and bound algorithm which proves to be very efficient and can handle successfully large general non-slicing floorplans. We show also how the non-slicing and the slicing algorithms can be combined to handle efficiently very large general floorplans.
Structural experiments with arrays of functions
Authors: J. Philip Benkard
Venue: ACM SIGAPL APL Quote Quad (1985)

Proposals have been made to include function arrays in APL syntax. Strand syntax extends to provide vectors; bracket semantics, to provide reshaping. Herein the structure phase of expression evaluation, which is APL's unique addition to the more familiar syntax and semantics phases, is analyzed. To the two argument shapes of VSAPL must be added the function shape. The extension of the conformance rules is straightforward; scalar conformance is the driving mechanism; applied recursively it is the basis of pervasion. Function and data arrays used with EACH and ENCLOSE, respectively, to produce scalars, lead to identities involving TRANSPOSE, DISCLOSE, and OUTER PRODUCT. Analysis of the nonpervasive scalar function RHO EACH suggests what structural information must be retained in an empty function array. A vector of derived functions is a useful alternative to a derived function with an EACH in some common circumstances. A historical survey suggests that adding function vectors to APL2 would enhance the symmetry and balance of the language.
Using dimensions to represent attributes
Authors: Dan M. King
Venue: ACM SIGAPL APL Quote Quad (1985)

In the design of a data base (DB) the grouping of attributes that define or describe a data entity can be represented as an object with many dimensions. This concept can serve as a framework for APL functions which provide efficient data extraction, manipulation and updating. The use of generalized data access functions to respond to specialized data requests can greatly simplify data gathering and reporting system code.
A multiple floating point coprocessor architecture
Authors: Lawrence Rauchwerger, P. Michael Farmwald
Venue: Proceedings of the 23rd annual workshop and symposium on Microprogramming and microarchitecture (1990)

General purpose microprocessor based computers usually speed their arithmetic processing performance by using a floating point co-processor. Because adding more co-processors represents neither a technological nor a cost problem we investigated a system based on a MIPS R2000 [2] and 4 floating point units. In this paper we show a block diagram of such an implementation and how two important scientific operations can be accelerated using a single unmodified data bus. A large percentage of the engineering applications are solved with the help of linear algebra methods like BLAS3 [4] algorithms; It is precisely for these primitives that the proposed architecture brings significant performance gains. The first operation described will be a matrix multiplication algorithm, its timing diagram and some results, Next a polynomial evaluation technique will be examined. Finally we show how to use the same ideas with various other microprocessors.
An Algorithm for Finding the Largest Approximately Common Substructures of Two Trees
Authors: Jason T. L. Wang, Bruce A. Shapiro, Dennis Shasha, Kaizhong Zhang, Kathleen M. Currey
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (1998)

Ordered, labeled trees are trees in which each node has a label and the left-to-right order of its children (if it has any) is fixed. Such trees have many applications in vision, pattern recognition, molecular biology and natural language processing. We consider a substructure of an ordered labeled tree T to be a connected subgraph of T. Given two ordered labeled trees T1 and T2 and an integer d, the largest approximately common substructure problem is to find a substructure U1 of T1 and a substructure U2 of T2 such that U1 is within edit distance d of U2 and where there does not exist any other substructure V1 of T1 and V2 of T2 such that V1 and V2 satisfy the distance constraint and the sum of the sizes of V1 and V2 is greater than the sum of the sizes of U1 and U2. We present a dynamic programming algorithm to solve this problem, which runs as fast as the fastest known algorithm for computing the edit distance of two trees when the distance allowed in the common substructures is a constant independent of the input trees. To demonstrate the utility of our algorithm, we discuss its application to discovering motifs in multiple RNA secondary structures (which are ordered labeled trees).
Specification of an algorithm design system
Authors: James Ten Eyck, G. Sampath, Richard Goldstone
Venue: ACM SIGCSE Bulletin (1998)

This paper describes an Internet based system for studying the design of algorithms and the structure of mathematical proofs. The Algorithm Design System consists of a framework for the construction and maintenance of the learning environment by a distributed group of contributors, and a set of web pages, produced by the contributors, that form the learning environment used by students of algorithm analysis and design. The framework of the system that we describe allows for the material used by students to grow dynamically in a distributed environment and provides constraints to ensure the uniformity of form and quality of content of the end product. The paper discusses both the architecture of the system and the content of the pages that it produces.
Modeling design tasks and tools: the link between product and flow model
Authors: Bernd Schürmann, Joachim Altmeyer
Venue: Proceedings of the 34th annual Design Automation Conference (1997)

The important step towards a comprehensiveCAD framework is the development of a suitable, completedesign model on which the design system's components arebased. To date, we generally find "island" solutions for differentaspects as data and process management, but in future, weneed more and more integrated solutions. Only the integrationgives us the traceability we need for design planning, to generateparts of the design toolýs code automatically, etc.This paper describes how a suitable Design Task Model canbe used to link the Product and Flow Models which are currentlyseparated in most frameworks. Using the PLAYOUTDesign Model as an example, we show how the Product, theTask, and the Flow Models may fit together, and we describe amodeling environment that guarantees the development ofconsistent, integrated models.
Clock Distribution Methodology for PowerPC&trade;Microprocessors
Authors: Shantanu Ganguly, Daksh Lehther, Satyamurthy Pullela
Venue: Journal of VLSI Signal Processing Systems (1997)

Clock distribution design for high performance microprocessors has become increasingly challenging in recent years. Design goals of state-of-the-art integrated circuits, dictate the need for clock networks with smaller skew tolerances, large sizes, and lower capacitances. In this paper we discuss some of the issues in clock network design that arise in this context. We describe the clock design methodology and techniques used in the design of clock distribution networks for PowerPC&trade; microprocessors that aim at alleviating some of these problems.
Ada in concert
Authors: Jack Beidler
Venue: ACM SIGAda Ada Letters (1997)

In a concert, it is truly marvelous how a diverse group of musicians playing an assortment of musical instruments come together to produce beautiful music. A point that is frequently made by those familiar with the new Ada standard, referred to here as Ada(95), is how the features in Ada(95) come together to enhance the software development process. This paper contains several examples that illustrate how the new features in Ada(95) dramatically improve the correlation between the design of a solution and its eventual implementation at the source code level when compared to Ada(83).The example, binary tree packaging, illustrates the design and implementation of recursive data structures. A data structure is recursive if the structure contains one or more substructures of the type being defined. As a result, recursive data structures lend themselves to processing with recursive algorithms. Lists, binary trees, and n-ary trees are examples of data structures that may be defined recursively. The example presented here is a package that implements binary trees using a recursive paradigm. The paper compares an Ada 83 solution with a solution using Ada 95. The paper focuses on how Ada 95 allows us to create a solution that more closely mirrors the specifications for the recursive data structure with improved time, space, and coding efficiency over an Ada 83 implementation. In a sense, this paper provides one illustration of how the '95 standard improves Ada.
Data groups: specifying the modification of extended state
Authors: K. Rustan M. Leino
Venue: ACM SIGPLAN Notices (1998)

This paper explores the interpretation of specifications in the context of an object-oriented programming language with subclassing and method overrides. In particular, the paper considers annotations for describing what variables a method may change and the interpretation of these annotations. The paper shows that there is a problem to be solved in the specification of methods whose overrides may modify additional state introduced in subclasses. As a solution to this problem, the paper introduces data groups, which enable modular checking and rather naturally capture a programmer's design decisions.
Design: a financial modelling system
Authors: Fred Appleyard, Roger Hui
Venue: ACM SIGAPL APL Quote Quad (1985)

A non-procedural financial modelling system is presented. The financial models can be deterministic or probabilistic. Some issues in the design and implementation of this system are discussed.
Blocking Sets in (v,{ 2, 4}, 1)-Designs
Authors: Lynn Margaret Batten, Kris Coolsaet, Anne Penfold Street
Venue: Designs, Codes and Cryptography (1997)

The existence of blocking sets in (v, {2, 4}, 1)-designs is examined. We show that for v &equiv; 0, 3, 5, 6, 7, 8, 9, 11 (mod 12), blocking sets cannot exist. We prove that for each v &equiv; 1, 2, 4 (mod 12) there is a (v, {2, 4}, 1)-design with a blocking set with three possible exceptions. The case v &equiv; 10 (mod 12) is still open; we consider the first four values of v in this situation.
A Lexicon Driven Approach to Handwritten Word Recognition for Real-Time Applications
Authors: Gyeonghwan Kim, Venu Govindaraju
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (1997)

A fast method of handwritten word recognition suitable for real time applications is presented in this paper. Preprocessing, segmentation and feature extraction are implemented using a chain code representation of the word contour. Dynamic matching between characters of a lexicon entry and segment(s) of the input word image is used to rank the lexicon entries in order of best match. Variable duration for each character is defined and used during the matching. Experimental results prove that our approach using the variable duration outperforms the method using fixed duration in terms of both accuracy and speed. Speed of the entire recognition process is about 200 msec on a single SPARC-10 platform and the recognition accuracy is 96.8 percent are achieved for lexicon size of 10, on a database of postal words captured at 212 dpi.
Modeling issues in a shipping system
Authors: Edward J. Williams, Susan Khoubyari
Venue: Proceedings of the 28th conference on Winter simulation (1996)

We describe the application of simulation and statistical analyses to the improvement of a shipping and distribution system supporting a component-fabrication plant and two automotive assembly plants interconnected by truck lines and railroads. These analyses enabled managers to determine the number and location of loading docks required, optimize the inventory level and distribution of racks (containers) circulating throughout this shipping system, determine the sizes of turnaround areas for truck and rail cargo at each plant, and predict annual truck and rail shipping volumes and costs.
Optimal shape function for a bi-directional wire under Elmore delay model
Authors: Youxin Gao, D. F. Wong
Venue: Proceedings of the 1997 IEEE/ACM international conference on Computer-aided design (1997)

In this paper, we determine the optimal shape function for a bi-directional wire under the Elmore delay model. Given a bi-directional wire of length L, let f(x) be the width of the wire at position x, 0\leq x \leq L. Let T_{DR} be the right-to-left delay. Let T_{DL} be the left-to-right delay. Let T_{BD}=\alpha T_{DR}+\beta T_{DL} be the total weighted delay where \alpha\geq 0 and \beta\geq 0 are given weights such that \alpha+\beta=1. We determine f(x) so that T_{BD} is minimized. Our study shows that, if \alpha=\beta, the optimal shape function is f(x)=c, for some constant c; if \alpha\neq \beta, the optimal shape function can be expressed in terms of the Lambert's W function as f(x)=-\frac{c_f}{2c_0}(\frac{1}{W(-ae^{-bx})}+1), where c_f is the unit length fringing capacitance, c_0 is the unit area capacitance, a and b are constants in terms of the given circuit parameters. If \alpha=0 or \beta=0, our result gives the optimal shape function for a uni-directional wire.
On Computing Stable Lagrangian Subspaces of Hamiltonian Matrices and Symplectic Pencils
Authors: Wen-Wei Lin, Chern-Shuh Wang
Venue: SIAM Journal on Matrix Analysis and Applications (1997)

This paper presents algorithms for computing stable Lagrangian invariant subspaces of a Hamiltonian matrix and a symplectic pencil, respectively, having purely imaginary and unimodular eigenvalues. The problems often arise in solving continuous- or discrete-time $H^{\infty}$-optimal control, linear-quadratic control and filtering theory, etc. The main approach of our algorithms is to determine an isotropic Jordan subbasis corresponding to purely imaginary (unimodular) eigenvalues by using the associated Jordan basis of the square of the Hamiltonian matrix (the $S+S^{-1}$-transformation of the symplectic pencil). The algorithms preserve structures and are numerically efficient and reliable in that they employ only orthogonal transformations in the continuous case.
Exactly Learning Automata of Small Cover Time
Authors: Dana Ron, Ronitt Rubinfeld
Venue: Machine Learning (1997)

We present algorithms for exactly learning unknown environments that can be described by deterministic finite automata. The learner performs a walk on the target automaton, where at each step it observes the output of the state it is at, and chooses a labeled edge to traverse to the next state. The learner has no means of a reset, and does not have access to a teacher that answers equivalence queries and gives the learner counterexamples to its hypotheses. We present two algorithms: The first is for the case in which the outputs observed by the learner are always correct, and the second is for the case in which the outputs might be corrupted by random noise. The running times of both algorithms are polynomial in the cover time of the underlying graph of the target automaton.