ppxscal/embedding_network huggingface dataset:
On embedded products of Grassmannians
Authors: Hans Havlicek, Corrado Zanella
Venue: Discrete Mathematics (2003)

Let Γ' and Γ be two Grassmannians. The standard embedding φ : Γ' × Γ → P is obtained by combining the Plücker and Segre embeddings. Given a further embedding η : Γ' × Γ' → P', we find a sufficient condition for the existence of α ε Aut(Γ) and of a collineation ψ : P → P' such that η= (idΓ' × α)φψ.
Introduction to Level Design for PC Games
Authors: Andy Charles Clayton
Venue:  (2003)

:SKILLS NEEDED To get the most out of this book, you should be technically proficient with software so that you can install and configure gmax and Tempest. You should also be familiar with compression software such as WinZip, and a text editor (Wordpad or Notepad). Some 3D experience is desirable but not essential, because detailed instructions are given in the tutorials. On The CD! Full version of gmax 1.2 Trial version of Photoshop 7 Finished versions of the tutorial files Completed levels for Unreal Tournament 2003 and Quake III Arena Textures referred to in the tutorials Color figures by chapter Additional configuration information Guide to Internet game level creation sites SYSTEM REQUIREMENTS: Windows® 2000/XP, Intel®, or AMD processor at 300 MHz, 128MB RAM and 300MB swap space, Graphics card supporting 1024 x 768 x 16-bit color (OpenGL and Direct3D hardware acceleration supported), Windows-compliant pointing device, CD-ROM drive, Internet Explorer 5.0 (IE 5.5 recommended and available for download), Macromedia Flash Player (included with the gmax installer). gmax and Tempest correctly installed, and Photoshop 7 (trial version included) and Photoshop Targa Plug-in (available for download). To run the level produced in Chapter 10, Quake III Arena must be installed on your computer. To run the games mentioned in the tutorials, you need a full copy of the game.
Learning in Parallel
Authors: Jeffrey S Vitter, Jyh Lin
Venue:  (1988)

In this paper, we extend Valiant''s sequential model of concept learning from examples [Valiant 1984] and introduce models for the efficient learning of concept classes from examples {\em in parallel}. We say that a concept class is {\em NC-learnable} if it can be learned in polylog time with a polynomial number of processors. We show that several concept classes which are polynomial-learnable are {\em NC}-learnable in constant time. Some other classes, such as {\em s}-fold unions of geometrical objects in Euclidean space, which are polynomial-learnable by a greedy technique, are {\em NC}-learnable using a non-greedy technique. Some problems can be shown to be {\em NC}-learnable, but must require more than constant time. We also show that (unless $P \subset RNC$) several concept classes related to linear programming are not {\em NC}-learnable. We conclude by investigating some fault-tolerant parallel learning algorithms.
An iterative method for a class of nonlinear large scale (near) constrained problems
Authors: M. H. B. M. Shariff
Venue: Proceedings of the sixth conference on Computational structures technology (2002)

A class of nonlinear (near) constrained problems is defined. The problems are reformulated to overcome numerical difficulties associated with near constrained problems. An iterative algorithm, which is suitable for large scale problems and can be easily parallelised, is proposed to solve the reformulated problems. Convergence properties of the proposed algorithm are investigated and numerical tests are done on the proposed algorithm. In the limiting case where the constraints are satisfied exactly the proposed algorithm is equivalent to the augmented Lagrangian method.
Engineering Fault-Tolerant Distributed Computing Systems
Authors: Ozalp Babaoglu
Venue:  (1986)

We view the design of fault-tolerant computing systems as an engineering endeavor. As such, this activity requires understanding the theoretical limitations and the scope of the feasible designs. We survey the impact that various environment characteristics and design choices have on the resultant system properties. We propose a single metric the system reliability as an appropriate measure for exploring tradeoffs among a potentially-large design space.
Lagrangian approach to jet mixing and optimization of the reactor for production of carbon nanotubes
Authors: Salas Alex Povitsky and Manuel D.
Venue:  (2001)

This study was motivated by an attempt to optimize the High Pressure carbon oxide (HiPco) process for the production of carbon nanotubes from gaseous carbon oxide. The goal is to achieve rapid and uniform heating of catalyst particles by an optimal arrangement of jets. A mixed Eulerian and Lagrangian approach is implemented to track the temperature of catalyst particles along their trajectories as a function of time. The FLUENT CFD software with second-order upwind approximation of convective terms and an algebraic multigrid-based solver is used. The poor performance of the original reactor configuration is explained in terms of features of particle trajectories. The trajectories most exposed to the hot jets appear to be the most problematic for heating because they either bend towards the cold jet interior or rotate upwind of the mixing zone. To reduce undesirable slow and/or oscillatory heating of catalyst particles, a reactor configuration with three central jets is proposed and the optimal location of the central and peripheral nozzles is determined. The ACM Portal is published by the Association for Computing Machinery. Copyright © 2010 ACM, Inc. Terms of Usage Privacy Policy Code of Ethics Contact Us Useful downloads: Adobe Acrobat QuickTime Windows Media Player Real Player
Hardware/software fault tolerance with multiple task modular redundancy
Authors: C. P. Fuhrman, S. Chutani, H. J. Nussbaumer
Venue: Proceedings of the IEEE Symposium on Computers and Communications (ISCC'95) (1995)

N-modular redundancy (NMR) and N-version programming (NVP) are two popular fault tolerance techniques in which hardware and software redundancy is exploited to mask faults. Redundant hardware is used to improve fault tolerance rather than throughput. We introduce a scheme for combined hardware-software fault tolerance derived from NMR and NVP that shows how redundancy can also be used to improve throughput by grouping the execution of several tasks. Our scheme uses a dynamic task allocation algorithm with an optimistic execution policy where the number of task executions is kept close to the minimum required to produce fault-free results. For equivalent hardware and software resources, the proposed method is 50% to 100% more efficient in terms of throughput and latency.
Routing Indices For Peer-to-Peer Systems
Authors: Arturo Crespo, Hector Garcia-Molina
Venue: Proceedings of the 22 nd International Conference on Distributed Computing Systems (ICDCS'02) (2002)

Finding information in a peer-to-peer system currently requires either a costly and vulnerable central index, or flooding the network with queries. In this paper we introduce the concept of Routing Indices (RIs), which allow nodes to forward queries to neighbors that are more likely to have answers. If a node cannot answer a query, it forwards the query to a subset of its neighbors, based on its local RI, rather than by selecting neighbors at random or by flooding the network by forwarding the query to all neighbors. We present three RI schemes: the compound, the hop-count, and the exponential routing indices. We evaluate their performance via simulations, and find that RIs can improve performance by one or two orders of magnitude vs. a flooding-based system, and by up to 100% vs. a random forwarding system. We also discuss the tradeoffs between the different RI schemes and highlight the effects of key design variables on system performance.
The Complexity of Fine Motion Planning
Authors: B. K. Natarajan
Venue:  (1986)

We study the complexity of fine motion planning for robots with position measurement and damping. A reduction from fine motion planning with position measurement only to the ``classical piano mover''s problem'''' is developed, thereby showing it to be feasible in polynomial time. We then show that deciding the existence of fine motion plans for robots with damping in three dimensional scenes is PSPACE-hard and, with a view to finding the cause for the jump in the complexity, we identify a restricted subclass of the PSPACE-hard problem that is PSPACE-complete. Finally, we show how to restrict this subclass to permit polynomial time algorithms for the problems in it.
MPEG-4 Support to Multiuser Virtual Environments
Authors: G. Todesco, R. B. Araujo
Venue: Proceedings of the The 20th International Conference on Distributed Computing Systems ( ICDCS 2000) (2000)

The few existing virtual reality distributed systems integrated to multimedia suffer from technical limitations on the number of users supported and on the presentation quality of the scenes. These limitations are due, among other things, to the slow progress of the VRML language to deal with multimedia integration. Today, the MPEG-4 standard is one of the most attractive alternative technologies to the development of multiuser virtual environments integrated to multimedia.This paper evaluates the current status of multimedia integration to virtual environments in the WWW and proposes a tool called SVRT-MM (Shared Virtual Reality Tool Integration with Multimedia) that extends an existing MPEG-4 player to support multiuser. This work intends to be a contribution to the ongoing developments of the MPEG-4 standard related to multiuser support in 3D environments.
Trace-Level Reuse
Authors: Antonio Gonzalez, Jordi Tubella, Carlos Molina
Venue: Proceedings of the 1999 International Conference on Parallel Processing (1999)

Trace-level reuse is based on the observation that some traces (dynamic sequences of instructions) are frequently repeated during the execution of a program, and in many cases, the instructions that make up such traces have the same source operand values. The execution of such traces will obviously produce the same outcome and thus, their execution can be skipped if the processor records the outcome of previous executions.This paper presents an analysis of the performance potential of trace-level reuse and discusses a preliminary realistic implementation. Like instruction- level reuse, trace-level reuse can improve performance by decreasing resource contention and the latency of some instructions. However, we show that trace- level reuse is more effective than instruction-level reuse because the former can avoid fetching the instructions of reused traces. This has two important benefits: it reduces the fetch bandwidth requirements, and it increases the effective instruction window size since these instructions do not occupy window entries. Moreover, trace-level reuse can compute all at once the result of a chain of dependent instructions, which may allow the processor to avoid the serialization caused by data dependences and thus, to potentially exceed the dataflow limit.
On the use of Verilog HDL in the conversion of existing hardware designs to newer technology
Authors: D. Crate
Venue: Proceedings of the 1996 IEEE International Verilog HDL Conference (IVC '96) (1996)

The trend towards greater integration of hardware continues, with the attendant benefits of increased density, speed, manufacturability, and reliability. When the updating of an existing design to a new hardware technology becomes necessary, its adaptation must allow for the differences in speed, structure and function of the new hardware medium. With the appearance of hardware description languages and the powerful CAE tools now available, the prospect of automating such a process appears plausible. We consider the "re-spin" of a board design from a TTL/PLD implementation to a gate array implementation, and the question of the automated conversion of hardware designs.
Monitoring of Aircraft Operation Using Statistics and Machine Learning
Authors: Fazel Famili, Sylvain Létourneau
Venue: Proceedings of the 11th IEEE International Conference on Tools with Artificial Intelligence (1999)

This paper describes the use of statistics and machine learning techniques to monitor the performance of commercial aircraft operation. The purpose of this research is to develop methods that can be used to generate reliable and timely alerts so that engineers and fleet specialists become aware of abnormal situations in large fleet of commercial aircraft that they manage. We introduce three approaches that we have used for monitoring engines and generating alerts. We also explain how additional information can be generated from machine learning experiments so that the parameters influencing the particular abnormal situation and their ranges are also identified and reported. Various benefits of fleet monitoring are explained in the paper.
Solving certain queueing problems by means of regular splittings
Authors: Paola Favati, B. Meini
Venue:  (1999)

We analyze the problem of the computation of the solution of the nonlinear matrix equation $X=\sum_{i=0}^{+\infty}X^iA_i$, arising in queueing models. We propose a technique based on regular splittings, that one hand leads to a new method for computing the solution, on the other hand it may be used to construct nonlinear matrix equations equivalent to starting one, that can be possibly solved by applying different algorithms. TEL:: 050593448 EMAIL:: favati@imc.pi.cnr.it
Utility-Based Planning
Authors: Sven Koenig, Reid G. Simmons
Venue:  (1993)

Probabilistic planning methods can have various objectives: usually they either maximize the probability of goal achievement or minimize the expected execution cost of the plan, and therefore assume that the agent that executes the plan has a risk-neutral attitude. Although there are many situations where risk-sensitive behavior is more appropriate, researchers have largely ignored the question how to incorporate risk-sensitive attitudes into their planning mechanisms. Utility theory shows that it is rational to maximize expected utility, given that the agent accepts a few simple axioms and has unlimited planning resources available. Thus, researchers might believe that one could allow for risk-sensitive attitudes by replacing all costs with their respective utilities (for an appropriate utility function). We show that this is usually not the case and, moreover, that --- in general --- the best action in a state can depend on the total cost that the agent has already accumulated (that is, the Markov property does not need to hold). However, we demonstrate how one can transform planning problems for risk-sensitive agents into equivalent ones for risk-neutral agents provided that exponential utility functions are used. The transformed planning problems can then be solved with probabilistic AI planning methods or, alternatively, dynamic programming methods. If the agent is risk-seeking, then one can use any planning method on the transformed planning problem that either minimizes (or satisfices) the expected execution cost or, alternatively, maximizes (or satisfices) the probability of goal achievement. The better a plan is for the transformed planning problem, the better it is for the original planning problem as well. Thus, one can extend the functionality of these plannersto risk-sensitive planning. To demonstrate our algorithms, we use a probabilistic planning framework ("probabilistic decision graphs") that can easily be mapped into Markov decision problems. It allows one to describe probabilistic effects of actions, actions with different costs (resource consumption), and goal states with different rewards (goodness). We then apply probabilistic decision graphs to finding optimal plans for risk-sensitive agents in a stochastic blocks-world domain and a stochastic path-planning domain.
Flexible Wide-area Group Communication Protocols - International Experiments
Authors: Takayuki Tachikawa, Hiroaki Higaki, Makoto Takizawa, Mario Gerla, Ming T. Liu, Misbah Deen
Venue: Proceedings of the 1998 International Conference on Parallel Processing Workshops (1998)

In distributed applications, a group of multiple processes is required to be cooperated by exchanging multimediadata.In addition, world-wide distributed applicationsare being realized by using the Internet.Thetraditional group communication protocols assume thatevery pair of processes support the same and fixed delaytime and reliability level.In world-wide multimediaapplications, the assumption does not hold.Wediscuss high-speed protocols which can change the waysfor distributing messages to multiple destinations andretransmitting messages to processes losing the messagesin the wide-area group in the change of the delayand reliability.We present the evaluation of theprotocols in the world-wide environment.
No Free Lunches in Multi-Agent Systems - A Characteristic Distribution Approach to Game Theoretic Modelling
Authors: Stefan J. Johansson
Venue: Proceedings of the Fourth International Conference on Computational Intelligence and Multimedia Applications (2001)

We introduce the notion of Characteristic Distributions which is a way of representing information about the payoffs of different behaviors in a Multi-agent System.We discuss how they can be used to simplify and structure the analysis of strategies and prove i) the existence of optimal environments, given a certain behavior, and ii) that all behaviors payoff equally, when taken over all possible environments (no free lunch theorem for strategies).
A methodology for proving termination of general logic programs
Authors: Elena Marchiori
Venue:  (1995)

Termination of logic programs with negated body atoms, here called general logic programs, is an important topic. This is also due to the fact that the computational mechanisms used to process negated atoms, like Clark''s negation as failure and Chan''s constructive negation, are based on termination conditions. This paper introduces a methodology for proving termination of general logic programs, when the Prolog selection rule is considered. This methodology is based on the notions of low-up-acceptable program. We prove that low-up-acceptable programs characterize a class of general logic programs which terminate for a large class of queries, which contains the set of all ground queries. We consider as operational model SLD-resolution augmented with a procedure to deal with negative literals, known as Chan''s constructive negation. General logic programs can be used to express concepts and problems in non-monotonic reasoning. We show here, that interesting problems in non-monotonic reasoning can be formalized and implemented by means of up-low-general logic programs.
MySQL: Visual QuickStart Guide
Authors: Larry Ullman
Venue:  (2002)

:With the Web extending into every nook and cranny of modern life, there are plenty of folks out there who have data storage issues that need to be addressed-Qbut no million-dollar budgets to do so. Luckily for them, there's MySQL. Offering Oracle-like power without the huge price tag, MySQL offers a networked database that can be accessed in numerous ways-Qall of which are described in this invaluable reference. In the clear, concise language readers have come to expect from this popular series, this Visual QuickStart Guide demonstrates how to interact with MySQLboth directly and through various popular programming languages (for example, PHP, Perl, and Java). Step-by-step instructions, practical examples, plenty of screen shots, and loads of useful tips and tricks make learning MySQL a breeze, even for novice programmers. Focusing first on the underlying conceptsQWhat are databases? What is MySQL?author Larry Ullman then proceeds through installation, administration, database design, and more before tackling MySQL's use with various programming languages, database programming techniques, and utilities. Web developers, system administrators, programmers, and just about anybody who uses databases will find themselves turning again and again to this essential guide.
Reduced-Order Modeling Based on PRONY's and SHANK's Methods via the Bilinear Transformation
Authors: Makram M. Mansour, Amit Mehrotra
Venue: Proceedings of the 4th International Symposium on Quality Electronic Design (2003)

In this paper, we propose a new model-order reductiontechnique for linear dynamic systems. The idea behind thistechnique is to transform the dynamic system function fromthe s-domain into the z-domain via the bilinear transformation,then use Prony's [1, 2] or Shank's [3] least-squaresapproximation methods instead of the commonly employedPadé approximation method, and finally transform the reducedsystem back into the s-domain using the inverse bi-lineartransformation. Simulation results for large practicalsystems show that this technique based on Prony's andShank's methods give much higher accuracy than the traditionalPadé method, and result in lower-order approximationswith negligible increase in simulation time.
A New Construct for Systems Modeling and Theory: The Kind
Authors: Joseph R. Kiniry
Venue:  (1998)

Our primary research goal is the development of theories and technology to facilitate the design, implementation, and management of complex systems. Complex systems, in this context, are any systems which exhibit "interesting" behavior including, but not limited to, nondeterminism, collective or emergent behavior, and adaptability. We can claim to understand a system only when we can describe how it works (e.g. provide a specification) such that, if it is a constructive system, another can build it. This notion is our constructive peer of the traditional scientific method: repeatability of results is equivalent to repeatability of construction. Abstraction is recognized as a key to understanding complex systems. While increasing our abstraction level results in a more complete metamodel (i.e. we can talk about more systems because we can talk about more complex systems), it also means a more complex metamodel. On the other hand, we don''t want to create theories and systems that only an expert can use. We need abstractions that are useful, comprehensible, and manipulable by humans (modelers, simulators, designers, developers, tool builders, etc.) and systems. In our experience, the highest-level abstractions in use today (e.g. classes, objects, types, subjects) can not model the systems we are interested in exploring. A higher-level abstraction missing: an "ubertype" of sorts - a syntactic and semantic bridge between types. We call this new abstraction a "kind". This paper will briefly describe kinds and provide several examples of their use.