ppxscal/embedding_network huggingface dataset:
Universal dynamic synchronous self-stabilization
Authors: Paolo Boldi, Sebastiano Vigna
Venue: Distributed Computing (2002)

We prove the existence of a "universal" synchronous self-stabilizing protocol, that is, a protocol that allows a distributed system to stabilize to a desired nonreactive behaviour (as long as a protocol stabilizing to that behaviour exists). Previous proposals required drastic increases in asymmetry and knowledge to work, whereas our protocol does not use any additional knowledge, and does not require more symmetry-breaking conditions than available; thus, it is also stabilizing with respect to dynamic changes in the topology. We prove an optimal quiescence time n+D for a synchronous network of n processors and diameter D; the protocol can be made finite state with a negligible loss in quiescence time. Moreover, an optimal D + 1 protocol is given for the case of unique identifiers. As a consequence, we provide an effective proof technique that allows to show whether self-stabilization to a certain behaviour is possible under a wide range of models.
Q-Learning for Risk-Sensitive Control
Authors: V. S. Borkar
Venue: Mathematics of Operations Research (2002)

We propose for risk-sensitive control of finite Markov chains a counterpart of the popular Q-learning algorithm for classical Markov decision processes. The algorithm is shown to converge with probability one to the desired solution. The proof technique is an adaptation of the o.d.e. approach for the analysis of stochastic approximation algorithms, with most of the work involved used for the analysis of the specific o.d.e.s that arise.
Propositional calculus under adjointness
Authors: Nehad N. Morsi
Venue: Fuzzy Sets and Systems (2002)

we develop a formal system for the class of all implications A and conjunctions K, on partially ordered sets (L, ≤) with top elements 1, such that A and K are related by adjointness and they satisfy the neutrality principle (that is, 1 is their left identity element). We call the resulting logic propositional calculus under adjointness, abbreviated AdjPC.Most algebraic theorems on those (L, ≤), A and K are inequalities in the posets (L, ≤) of truth values. In consequence, we have to find means for abstracting inequalities within syntax; which must be free from partial truth values. This is achieved by employing a further, implication-like adjoint H of A and K, whereby the partial order of (L, ≤) coincides with the binary relation H(•, •) = 1. Accordingly, the semantical domain for AdjPC should become the class of all such quintuples (L, ≤ ,A,K,H), which we call adjointness algebras.Our axiom scheme for AdjPC features seven axioms. However, it may be the case that no finite set of axioms can complete AdjPC if inference is carried out by means of modus ponens (MP) alone. This is because AdjPC is too general; it lacks some basic theorems of the more restricted logics (such as residuated logic and intuitionistic logic). As a result, we have to adopt four inference rules for AdjPC; namely, MP and three bits of the substitution theorem.We deduce enough theorems and inferences in AdjPC to delineate its basic structure. This enables us to establish the completeness of AdjPC for the semantical domain of adjointness algebras; by means of a quotient-algebra structure (a Lindenbaum type of algebra). We also show how certain models can help disprove some incorrect inferences in AdjPC.We end by developing complete syntax (with fewer axioms and inference rules) for the smaller semantical domain of all adjointness algebras whose implications satisfy the exchange principle.
Owner prediction for accelerating cache-to-cache transfer misses in a cc-NUMA architecture
Authors: Manuel E. Acacio, José González, José M. García, José Duato
Venue: Proceedings of the 2002 ACM/IEEE conference on Supercomputing (2002)

Cache misses for which data must be obtained from a remote cache (cache-to-cache transfer misses) account for an important fraction of the total miss rate. Unfortunately, cc-NUMA designs put the access to the directory information into the critical path of 3-hop misses, which significantly penalizes them compared to SMP designs. This work studies the use of owner prediction as a means of providing cc-NUMA multiprocessors with a more efficient support for cache-to-cache transfer misses. Our proposal comprises an effective prediction scheme as well as a coherence protocol designed to support the use of prediction. Results indicate that owner prediction can significantly reduce the latency of cache-to-cache transfer misses, which translates into speed-ups on application performance up to 12%. In order to also accelerate most of those 3-hop misses that are either not predicted or mispredicted, the inclusion of a small and fast directory cache in every node is evaluated, leading to improvements up to 16% on the final performance.
How Tight Are the Ties that Bind Stakeholder Groups?
Authors: Richard A. Wolfe, Daniel S. Putler
Venue: Organization Science (2002)

The purpose of stakeholder management is to facilitate our understanding of increasingly unpredictable external environments, thereby facilitating our ability to manage within these environments. We argue that a powerful implicit assumption within the stakeholder literature--that priorities within role-based stakeholder groups are relatively homogeneous--blurs our understanding of organization-stakeholder relationships. Two important and related areas of concern are presented. The first involves the primacy of role in stakeholder definition. This role primacy approach to stakeholder definition is appropriate if, for a particular issue, role-based stakeholder group members have similar priorities. Individual and collective self-interest provides a rationale for this assumption. However, an important problem with this approach arises in situations in which self-interest is not the primary motivator of individuals' priorities. In these instances, subgroups within different role-based stakeholder groups might have more similar priorities than either subgroup has with others within their role-based stakeholder group. In these situations the role primacy approach impedes, rather than facilitates, an understanding of our environment. Our second concern is related to insufficient rigor in the application of stakeholder analysis. Most stakeholder studies, both theoretical and empirical, fall short in the determination of relevant interests and the subsequent subdivision of role-based stakeholder groups into rigorously defined specific stakeholder groups. Having suggested that the role primacy approach to stakeholder definition is less than ideal, we examine the extent to which, and the conditions under which, roles are likely to determine priorities, and thus, the likelihood of relatively homogeneous priorities within role-based stakeholder groups. In addition, we present an illustrative empirical analysis of stakeholder group priorities. The illustrative study is conducted within the context of intercollegiate athletics. Related literature and our empirical results indicate that role-based self-interest frequently is not a sufficient "binding tie" of stakeholder groups. Given this background, we present an alternative approach to stakeholder analysis that borrows heavily from the customer segmentation literature of marketing. Our alternative approach can accommodate heterogeneous priorities within role-based stakeholder groups.
Grids and grid technologies for wide-area distributed computing
Authors: Mark Baker, Rajkumar Buyya, Domenico Laforenza
Venue: Software&mdash;Practice Experience (2002)

The last decade has seen a substantial increase in commodity computer and network performance, mainly as a result of faster hardware and more sophisticated software. Nevertheless, there are still problems, in the fields of science, engineering, and business, which cannot be effectively dealt with using the current generation of supercomputers. In fact, due to their size and complexity, these problems are often very numerically and/or data intensive and consequently require a variety of heterogeneous resources that are not available on a single machine. A number of teams have conducted experimental studies on the cooperative use of geographically distributed resources unified to act as a single powerful computer. This new approach is known by several names, such as metacomputing, scalable computing, global computing, Internet computing, and more recently peer-to-peer or Grid computing. The early efforts in Grid computing started as a project to link supercomputing sites, but have now grown far beyond their original intent. In fact, many applications can benefit from the Grid infrastructure, including collaborative engineering, data exploration, high-throughput computing, and of course distributed supercomputing. Moreover, due to the rapid growth of the Internet and Web, there has been a rising interest in Web-based distributed computing, and many projects have been started and aim to exploit the Web as an infrastructure for running coarse-grained distributed and parallel applications. In this context, the Web has the capability to be a platform for parallel and collaborative work as well as a key technology to create a pervasive and ubiquitous Grid-based infrastructure. This paper aims to present the state-of-the-art of Grid computing and attempts to survey the major international efforts in developing this emerging technology.
Formal design of real-time systems in a platform-independent way
Authors: Jozef Hooman, Onno van Roosmalen
Venue: Engineering of distributed control systems (2001)

To design distributed real-time systems, we distinguish two activities: (1) a platform-independent programming activity and (2) the realization of the resulting program on a particular execution platform. This paper concentrates on the first activity, proposing an extension of conventional (non-real-time) programming languages with so called timing annotations that specify the required timing constraints on an abstract level. A formal, axiomatic, semantics of a simple programming language with timing annotations is formulated, using specifications that are based on pre- and postconditions. Program correctness is independent of any underlying execution platform and can be proved by means of compositional proof rules. This is illustrated by a small example of a control system.
Defunctionalization at work
Authors: Olivier Danvy, Lasse R. Nielsen
Venue: Proceedings of the 3rd ACM SIGPLAN international conference on Principles and practice of declarative programming (2001)

Reynolds's defunctionalization technique is a whole-program transformation from higher-order to first-order functional programs. We study practical applications of this transformation and uncover new connections between seemingly unrelated higher-order and first-order specifications and between their correctness proofs. Defunctionalization therefore appearsboth as a springboard for rev ealing new connections and as a bridge for transferring existing results between the first-order world and the higher-order world.
The Probabilistic Set-Covering Problem
Authors: Patrizia Beraldi, Andrzej Ruszczynski
Venue: Operations Research (2002)

In a probabilistic set-covering problem the right-hand side is a random binary vector and the covering constraint has to be satisfied with some prescribed probability. We analyze the structure of the set of probabilistically efficient points of binary random vectors, develop methods for their enumeration, and propose specialized branch-and-bound algorithms for probabilistic set-covering problems.
Contract Assembly: Dealing with Combined Supply Lead Time and Demand Quantity Uncertainty
Authors: Jing-Sheng Song, Candace A. Yano, Panupol Lerssrisuriya
Venue: Manufacturing Service Operations Management (2000)

We consider a problem faced by a contract assembler that both assembles finished goods and procures the associated component parts for one of its major customers. Because of rapid changes in technology and ongoing engineering changes, all parts subject to obsolescence are purchased only for the current customer order. The procurement lead times of the components are random. Moreover, although the order for the finished product has a defined due date, the contract allows the customer to change the order quantity. Consequently, the assembler also faces a random demand. The assembler must determine how much to order and when to order each component part. The objective is to minimize the total expected cost, including the cost of holding components prior to their assembly, penalties for tardiness visa-vis the assembly due date, and overage and underage costs in satisfying the demand quantity. We present some structural results and discuss insights regarding optimal policies. We also present several simple heuristic policies and compare them to optimal policies. Computational results indicate that ignoring lead time variability can be costly, but relatively simple heuristics that consider lead time variability perform quite well.
Monitors: an operating system structuring concept
Authors: C. A. R. Hoare
Venue: The origin of concurrent programming: from semaphores to remote procedure calls (2002)

This paper develops Brinch Hansen's concept of a monitor as a method of structuring an operating system. It introduces a form of synchronization, describes a possible method of implementation in terms of semaphores and gives a suitable proof rule. Illustrative examples include a single resource scheduler, a bounded buffer, an alarm clock, a buffer pool, a disk head optimizer, and a version of the problem of readers and writers.
Optimal Dynamic Allocation of Treatment and Enforcement in Illicit Drug Control
Authors: Gernot Tragler, Jonathan P. Caulkins, Gustav Feichtinger
Venue: Operations Research (2001)

There has been considerable debate about what share of drug control resources should be allocated to treatment vs. enforcement. Most of the debate has presumed that there is one answer to that question, but it seems plausible that the mix of interventions should vary as the size of the problem changes. We formulate the choice between treatment and enforcement as an optimal control problem and reach the following conclusions. If initiation into drug use is an increasing function of the current number of users and control begins early, then it is optimal to use very large amounts of both enforcement and treatment to cut short the epidemic. Otherwise the optimal policy is not to stop the growth of the epidemic, but rather to moderate it. Initially this should be done primarily with enforcement. Over time, enforcement spending should increase, but not nearly so fast as treatment spending. Hence, treatment should receive a larger share of control resources when a drug problem is mature than when it is first growing. If initiation rates subsequently decline, enforcement's budget share should drop further in the ensuing declining stage of the epidemic.
Chrysler Leverages Its Suppliers' Improvement Suggestions
Authors: Janet L. Hartley, Bertie M. Greer, Seungwook Park
Venue: Interfaces (2002)

We examined Chrysler's SCORE (supplier cost reduction effort) supplier-suggestion process from the perspectives of Chrysler and its suppliers. Chrysler used SCORE to save over $2 billion and to build collaborative relationships with its suppliers. In our study, we observed four elements in Chrysler and its suppliers' organizations that contributed to SCORE's success: (1) designating a process champion, (2) engaging suppliers in the process, (3) motivating employees, and (4) facilitating evaluation and implementation. Companies designing a supplier-suggestion process should consider ways to reduce delays during evaluation, to minimize the number of low value suggestions, and to involve the entire supply chain.
Easily Testable Cellular Carry Lookahead Adders
Authors: Dimitris Gizopoulos, Mihalis Psarakis, Antonis Paschalis, Yervant Zorian
Venue: Journal of Electronic Testing: Theory and Applications (2003)

Cellular Carry Lookahead (CLA) adders are systematically implemented in arithmetic units due to their regular, well-balanced structure. In terms of testability and with respect to the classical Cell Fault Model (CFM), cellular CLA adders have poor testability by construction. Design-for-testability (DFT) modifications for cellular CLA adders have been proposed in the literature providing complete CFM testability making the adders either level-testable or C-testable. These designs impose significant area and performance overheads. In this paper, we propose DFT modifications for cellular CLA adders to achieve complete CFM testability with special emphasis on the minimum impact in terms of area and performance. Complete CFM testability is achieved without adding any extra inputs to the adder, with very small area and performance overheads, thus providing a practical solution. The proposed DFT scheme requires only 1 extra output and it is not necessary to put the circuit in a special test mode, while the earlier schemes require the addition of 2 extra inputs to set the circuit in test mode. A rigorous proof of the linear-testability of the adder is given and a sufficient linear-sized test set is provided that guarantees 100% CFM fault coverage. Surprisingly, the size of the proposed linear-sized test set is, in most practical cases, comparable or even smaller than a logarithmic-sized test set proposed in the literature.
Dynamic query sliders vs. brushing histograms
Authors: Qing Li, Xiaofeng Bao, Chen Song, Jinfei Zhang, Chris North
Venue: CHI '03 extended abstracts on Human factors in computing systems (2003)

Dynamic queries facilitate exploration of information through real-time visual display of both query formulation and results. Dynamic query sliders are linked to the main visualization to filter data. A common alternative to dynamic queries is to link several simple visualizations, such as histograms, to the main visualization with a brushing interaction. Selecting data in the histograms highlights that data in the main visualization. We compare these two approaches in an empirical experiment on DynaMaps, a geographic data visualization tool. Dynamic query sliders resulted in better performance for simple range tasks, while brushing histograms was better for complex comparison, tradeoff, and pattern tasks. Participants preferred brushing histograms for understanding relationships between attributes.
Combining Minsum And Minmax: A Goal Programming Approach
Authors: Emilio Carrizosa, Dolores Romero-Morales
Venue: Operations Research (2001)

A number of methods for multiple-objective optimization problems (MOP) give as solution to MOP the set of optimal solutions for some single-objective optimization problems associated with it. Well-known examples of these single-objective optimization problems are the minsum and the minmax. In this note, we propose a new parametric single-objective optimization problem associated with MOP by means of Goal Programming ideas. We show that the minsum and minmax are particular instances, so we are somehow combining minsum and minmax by means of a parameter. Moreover, such parameter has a clear meaning in the value space. Applications of this parametric problem to classical models in Locational Analysis are discussed.
Measuring agreement in medical informatics reliability studies
Authors: George Hripcsak, Daniel F. Heitjan
Venue: Journal of Biomedical Informatics (2002)

Agreement measures are used frequently in reliability studies that involve categorical data. Simple measures like observed agreement and specific agreement can reveal a good deal about the sample. Chance-corrected agreement in the form of the kappa statistic is used frequently based on its correspondence to an intraclass correlation coefficient and the ease of calculating it, but its magnitude depends on the tasks and categories in the experiment. It is helpful to separate the components of disagreement when the goal is to improve the reliability of an instrument or of the raters. Approaches based on modeling the decision making process can be helpful here, including tetrachoric correlation, polychoric correlation, latent trait models, and latent class models. Decision making models can also be used to better understand the behavior of different agreement metrics. For example, if the observed prevalence of responses in one of two available categories is low, then there is insufficient information in the sample to judge raters' ability to discriminate cases, and kappa may underestimate the true agreement and observed agreement may overestimate it.
Introduction: E-government
Authors: Jeffrey Roy
Venue: Social Science Computer Review (2003)

The emergence of e-government may not be a natural evolution of existing public sector structures and processes, although the degree to which it is not drives much debate. Meaningful research on this topic could thus be helpful in providing a basis for more clarity, insight, and understanding of this important topic. The aim of this special issue on e-government is, as a result, to generate new and relevant scholarly contributions on the transformation at work in the public sector today, due to the growing online patterns of socioeconomic and political activity shaping individual and organizational behavior around the world.
MEMS tunable gratings with analog actuation
Authors: Wei-Chuan Shih, Chee Wei Wong, Yong Bae Jeon, Sang-Gook Kim, George Barbastathis
Venue: Information Sciences&mdash;Informatics and Computer Science: An International Journal (2003)

We have designed and fabricated tunable gratings with period tunable to within fraction of a nanometer. We actuated the gratings by electrostatic and piezoelectric means, and demonstrated period changes of order 1 nm. Fabrication processes for the two versions are presented. Devices characterization and experimental results are given for respective devices.
The First Linear-Programming Shoppe
Authors: Saul I. Gass
Venue: Operations Research (2002)

We review the early history of linear programming with respect to the solution of linear equations, computer developments, and its origins within the federal government.
The hierarchy of the cocoons of a graph and its application to image segmentation
Authors: Laurent Guigues, Hervé Le Men, Jean-Pierre Cocquerez
Venue: Pattern Recognition Letters (2003)

A set of particular subgraphs of a valued graph, called cocoons, is introduced. Within the image segmentation framework, the cocoons represent a model of contrasted regions. It is shown that the cocoons are organized into a hierarchy which is a sub-hierarchy of the one produced by the standard clustering algorithm of complete linkage. This result thus offers a new point of view on what the complete linkage algorithm achieves when it is applied on image data. For segmentation purposes, the hierarchy is built on a region adjacency graph valued with a dissimilarity function. It's construction is efficient, parameter free, and robust towards monotone transformations of the dissimilarities. It is illustrated that the simplest cut criterion in these hierarchies, based on thresholding an associated ultrametric distance, already produces meaningful segmentations.
Sleep Depth Oscillations: An Aspect to Consider in Automatic Sleep Analysis
Authors: Eero Huupponen, Sari-Leena Himanen, Joel Hasan, Alpo Värri
Venue: Journal of Medical Systems (2003)

The automatic sleep analysis aims at providing an accurate description of sleep process. We found that there exist so far poorly known sleep depth oscillations constantly. Quantitative analysis of these oscillations was done in this work via a mean frequency measure and FFT. Overall charasteristics of these oscillations were studied, focusing on the waves with period times of 50&ndash;150 s. These sleep depth oscillations have a relatively large amplitude and they should be considered in future sleep analysis systems. The results of this study give directions to automated sleep analysis regarding optimal estimation of sleep depth.