ppxscal/embedding_network huggingface dataset:
A compositional framework for complex queries over uncertain data
Authors: Michaela Götz, Christoph Koch
Venue: Proceedings of the 12th International Conference on Database Theory (2009)

The ability to flexibly compose confidence computation with the operations of relational algebra is an important feature of probabilistic database query languages. Computing confidences is computationally hard, however, and has to be approximated in practice. In a compositional query language, even very small errors caused by approximation can lead to an entirely incorrect result: A selection operation on an approximated probability can incorrectly keep or drop a tuple even if the probability value has been approximated to a very narrow confidence interval. In this paper, we study the query evaluation problem for compositional query languages for probabilistic databases with particular focus on providing overall result quality guarantees in the face of approximate intermediate results. We present a framework for evaluating compositional queries based on a new representation system that can capture uncertainty about probabilities. More specifically, we consider probability intervals instead of exact probabilities, interpreting tuples obtained by selection on approximate values as unreliable. We study the complexity of query evaluation over our new model. We present efficient confidence computation algorithms which compute bounds that are close to tight for important classes. For deciding a selection predicate, we show that no efficient randomized algorithm exists unless BPP&sup;NP. Still we are able to efficiently guess robust predicates with a good error bound. Putting all these pieces together in our framework, we evaluate queries using a decomposition into a relational algebra plan and an approximation plan. The latter allows to successively improve accuracy and error bounds, while the relational algebra plan only has to be executed once.
Comparison of Hybrid Control Schemes for Vibration Suppression of Flexible Robot Manipulator
Authors: M. A. Ahmad, A. N. K. Nasir, R. M. T. Raja Ismail, M. S. Ramli
Venue: Proceedings of the 2009 International Conference on Computer Modeling and Simulation (2009)

This paper presents a comparative assessment of control schemes for vibration suppression and end-point trajectory tracking of a flexible robot manipulator. A constrained planar single-link flexible robot manipulator is considered and the dynamic model of the system is derived using the assumed mode method. To study the effectiveness of the controllers, initially a collocated PD controller is developed for control of rigid body motion. This is then extended to incorporate a non-collocated PID controller and a feedforward controller based on input shaping techniques for control of vibration (flexible motion) of the system. For input shaping controller, the positive input shapers with different derivatives are proposed and designed based on the properties of the system. Simulation results of the response of the manipulator with the controllers are presented in time and frequency domains. The performances of the control schemes are assessed in terms of level of vibration reduction, input tracking capability and speed of response. Finally, a comparativeassessment of the control techniques is presented and discussed.
A framework for exploring numerical solutions of advection&#x2013;reaction&#x2013;diffusion equations using a GPU-based approach
Authors: Allen R. Sanderson, Miriah D. Meyer, Robert M. Kirby, Chris R. Johnson
Venue: Computing and Visualization in Science (2009)

In this paper we describe a general purpose, graphics processing unit (GP-GPU)-based approach for solving partial differential equations (PDEs) within advection&#x2013;reaction&#x2013;diffusion models. The GP-GPU-based approach provides a platform for solving PDEs in parallel and can thus significantly reduce solution times over traditional CPU implementations. This allows for a more efficient exploration of various advection&#x2013;reaction&#x2013;diffusion models, as well as, the parameters that govern them. Although the GPU does impose limitations on the size and accuracy of computations, the PDEs describing the advection&#x2013;reaction&#x2013;diffusion models of interest to us fit comfortably within these constraints. Furthermore, the GPU technology continues to rapidly increase in speed, memory, and precision, thus applying these techniques to larger systems should be possible in the future. We chose to solve the PDEs using two numerical approaches: for the diffusion, a first-order explicit forward Euler solution and a semi-implicit second order Crank&#x2013;Nicholson solution; and, for the advection and reaction, a first-order explicit solution. The goal of this work is to provide motivation and guidance to the application scientist interested in exploring the use of the GP-GPU computational framework in the course of their research. In this paper, we present a rigorous comparison of our GPU-based advection&#x2013;reaction&#x2013;diffusion code model with a CPU-based analog, finding that the GPU model out-performs the CPU implementation in one-to-one comparisons.
Support Vector Regression for Censored Data (SVRc): A Novel Tool for Survival Analysis
Authors: Faisal M. Khan, Valentina Bayer Zubek
Venue: Proceedings of the 2008 Eighth IEEE International Conference on Data Mining (2008)

A crucial challenge in predictive modeling for survival analysis is managing censored observations in the data. The Cox proportional hazards model is the standard tool for the analysis of continuous censored survival data. We propose a novel machine learning algorithm, Support Vector Regression for Censored Data (SVRc) for improved analysis of medical survival data. SVRc leverages the high-dimensional capabilities of traditional SVR while adapting it for use with censored data through a modified asymmetric loss/penalty function which allows censored (left and right censored) data to be processed. We applied the new algorithm to predict the recurrence and disease progression of prostate cancer, breast cancer and lung cancer. Compared with the traditional Cox model, SVRc achieves significant improvement in overall accuracy as well as in the ability to identify high-risk and low-risk patient populations.
Sobolev gradient approach for the time evolution related to energy minimization of Ginzburg-Landau functionals
Authors: Nauman Raza, Sultan Sial, Shahid S. Siddiqi
Venue: Journal of Computational Physics (2009)

The Sobolev gradient technique has been discussed previously in this journal as an efficient method for finding energy minima of certain Ginzburg-Landau type functionals [S. Sial, J. Neuberger, T. Lookman, A. Saxena, Energy minimization using Sobolev gradients: application to phase separation and ordering, J. Comput. Phys. 189 (2003) 88-97]. In this article a Sobolev gradient method for the related time evolution is discussed.
A metal-only-ECO solver for input-slew and output-loading violations
Authors: Chien Pang Lu, Mango C.-T. Chao, Chen Hsing Lo, Chih Wei Chang
Venue: Proceedings of the 2009 international symposium on Physical design (2009)

To shorten the time-to-market and reduce the expensive cost of photomasks in advance process technologies, metal-only ECO has become a practical and attractive solution to handle incremental design changes. Due to limited spare cells in metal-only ECO, the new added netlist may often violate the input-slew and outputloading constraints and, in turn, delay or even fail the timing closure. This paper proposes a framework, named MOESS, to solve the input-slew and output-loading violations by connecting spare cells onto the violated nets as buffers. MOESS provides two buffer insertion schemes performed sequentially to minimize the number of inserted buffers and then to solve timing violations if there is any. This framework has been silicon-validated through industrial designs with more than 1-million instances. The experimental results demonstrate that MOESS can solve more violations with less inserted buffers and less CPU runtime compared to an EDA vendor's solution. The whole framework is built based on a commercial APR tool and can be ported to any other APR tool offering open access to its design database.
Electromagnetic Radiations of FPGAs: High Spatial Resolution Cartography and Attack on a Cryptographic Module
Authors: Laurent Sauvage, Sylvain Guilley, Yves Mathieu
Venue: ACM Transactions on Reconfigurable Technology and Systems (TRETS) (2009)

Since the first announcement of a Side Channel Analysis (SCA) about ten years ago, considerable research has been devoted to studying these attacks on Application Specific Integrated Circuits (ASICs), such as smart cards or TPMs. In this article, we compare power-line attacks with ElectroMagnetic (EM) attacks, specifically targeting Field Programmable Gate Array devices (FPGAs), as they are becoming widely used for sensitive applications involving cryptography. We show experimentally that ElectroMagnetic Analysis (EMA) is always faster than the historical Differential Power Analysis (DPA) in retrieving keys of symmetric ciphers. In addition, these analyses prove to be very convenient to conduct, as they are totally non-invasive. Research reports indicate that EMA can be conducted globally, typically with macroscopic home-made coils circling the device under attack, with fair results. However, as accurate professional EM antennas are now becoming more accessible, it has become commonplace to carry out EM analyses locally. Cartography has been carried out by optical means on circuits realized with technology greater than 250 nanometers. Nonetheless, for deep submicron technologies, the feature size of devices that are spied upon is too small to be visible with photographic techniques. In addition, the presence of the 6+ metallization layers obviously prevents a direct observation of the layout. Therefore, EM imaging is emerging as a relevant means to discover the underlying device structure. In this article, we present the first images of deep-submicron FPGAs. The resolution is not as accurate as photographic pictures: we notably compare the layout of toy design examples placed at the four corners of the FPGAs with the EM images we collected. We observe that EM imaging has the advantage of revealing active regions, which can be useful in locating a particular processor (visible while active---invisible when inactive). In the context of EM attacks, we stress that the exact localization of the cryptographic target is not necessary: the coarse resolution we obtain is sufficient. We note that the EM imaging does not reveal the exact layout of the FPGA, but instead directly guides the attacker towards the areas which are leaking the most. We achieve attacks with an accurate sensor, both far from (namely on a SMC capacitor on the board) and close to (namely directly over the FPGA) the encryption co-processor. As compared to the previously published attacks, we report a successful attack on a DES module in fewer than 6,300 measurements, which is currently the best cracking performance against this encryption algorithm implemented in FPGAs.
A framework for beef traceability from farm to slaughter using global standards: An Irish perspective
Authors: C. Shanahan, B. Kernan, G. Ayalew, K. McDonnell, F. Butler, S. Ward
Venue: Computers and Electronics in Agriculture (2009)

A system that can be used to identify all aspects of beef traceability from farm to slaughter has been laid out based on pertinent European Union law and global standards. An integrated traceability system involving all of the stakeholders along the supply chain can serve to increase consumer confidence in beef products by making traceability data accessible to the consumer. The use of radio frequency identification (RFID) for the identification of individual cattle, and biometric identifiers for verification of cattle identity has been proposed. The use of a BioTrack database for the storage of retinal images has been outlined. A data structure for RFID tags has been proposed in accordance with ISO 11784 and a middleware to convert animal ID data to the EPC (electronic product code) data structure, in order to facilitate the use of EPCglobal Network for the exchange of traceability data.
Cybercrime 2.0: When the Cloud Turns Dark
Authors: Niels Provos, Moheeb Abu Rajab, Panayiotis Mavrommatis
Venue: Queue (2009)

Web-based malware attacks are more insidious than ever. What can be done to stem the tide?
Getting Started with Grails
Authors: Jason Rudolph
Venue:  (2007)

Grails is an open-source, rapid web application development framework that provides a super-productive full-stack programming model based on the Groovy scripting language and built on top of Spring, Hibernate, and other standard Java frameworks. Ruby on Rails pioneered the innovative coupling of a powerful programming language and an opinionated framework that favors sensible defaults over complex configuration, but many organizations aren't yet ready to stray from the safety of Java or forgo their current Java investments. Grails makes it possible to achieve equivalent productivity in a Java-centric environment. Over the course of this book, the reader will explore the various aspects of Grails and also experience Grails by building a Grails app.
A level set method for structural shape and topology optimization using radial basis functions
Authors: Zhen Luo, Liyong Tong, Zhan Kang
Venue: Computers and Structures (2009)

This paper presents an alternative level set method for shape and topology optimization of continuum structures. An implicit free boundary representation model is established by embedding structural boundary into the zero level set of a higher-dimensional level set function. An explicit parameterization scheme for the level set surface is proposed by using radial basis functions with compact support. In doing so, the originally more difficult shape and topology optimization, driven by the temporal and spatial Hamilton-Jacobi partial differential equation (PDE), is transformed into a relatively easier size optimization of the expansion coefficients of the basis functions. The design optimization is converted to an iterative numerical process that combines the parameterization with a derivation of the shape sensitivity of the design functions, so as to allow using mathematical programming algorithms to solve the level set-based design problem and avoid directly solving the Hamilton-Jacobi PDE. Furthermore, a numerically more stable and efficient volume integration scheme is proposed to implement calculations of the shape derivatives, leading to the creation of new holes which are generated initially along the boundary and then propagated to the interior of the design domain. Two widely studied examples are used to demonstrate the effectiveness of the proposed optimization method.
Languages
Authors: Russell J. Abbott
Venue: Proceedings of the May 19-22, 1980, national computer conference (1980)

This year the "Languages" technical area focuses on practical matters. The four sessions are all concerned with language issues arising from real world considerations. 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
Algorithm library based on algorithmic cyberFilms
Authors: Yutaka Watanobe, Nikolay Mirenkov, Rentaro Yoshioka
Venue: Knowledge-Based Systems (2009)

A library of algorithms developed as algorithmic cyberFilms is presented. Algorithmic cyberFilms are a new type of software components for presentation, specification/programming and automatic code generation of computational algorithms. The algorithmic cyberFilm format is implemented as a set of multimedia frames (and scenes), and each component is represented by frames of algorithmic skeletons representing dynamical features of an algorithm, by frames of integrated view providing static features of the algorithm in a compact format, and by corresponding template codes supporting the program generation. We developed a library which is a collection of basic and advanced algorithms taught at universities, including computation on grids, trees and graphs. In this paper, we present basic constructs of visual languages which are used for representing cyberFilms as well as for demonstrating the library components. We also provide a general overview of the library and its features. In addition, we discuss results of experiments which were conducted to verify the usability of the library components and their usefulness in education.
A Protocol for Secure Remote Updates of FPGA Configurations
Authors: Saar Drimer, Markus G. Kuhn
Venue: Proceedings of the 5th International Workshop on Reconfigurable Computing: Architectures, Tools and Applications (2009)

We present a security protocol for the remote update of volatile FPGA configurations stored in non-volatile memory. Our approach can be implemented on existing FPGAs, as it sits entirely in user logic. Our protocol provides for remote attestation of the running configuration and the status of the upload process. It authenticates the uploading party both before initiating the upload and before completing it, to both limit a denial-of-service attack and protect the integrity of the bitstream. Encryption protects bitstream confidentiality in transit; we either decrypt it before non-volatile storage, or pass on ciphertext if the configuration logic can decrypt it. We discuss how tamper-proofing the connection between the FPGA and the non-volatile memory, as well as space for multiple bitstreams in the latter, can improve resilience against downgrading and denial-of-service attacks.
Application of the GALI method to localization dynamics in nonlinear systems
Authors: T. Bountis, T. Manos, H. Christodoulidi
Venue: Journal of Computational and Applied Mathematics (2009)

We investigate localization phenomena and stability properties of quasiperiodic oscillations in N degree of freedom Hamiltonian systems and N coupled symplectic maps. In particular, we study an example of a parametrically driven Hamiltonian lattice with only quartic coupling terms and a system of N coupled standard maps. We explore their dynamics using the Generalized Alignment Index (GALI), which constitutes a recently developed numerical method for detecting chaotic orbits in many dimensions, estimating the dimensionality of quasiperiodic tori and predicting slow diffusion in a way that is faster and more reliable than many other approaches known to date.
The role of physical artefacts in agile software development: Two complementary perspectives
Authors: Helen Sharp, Hugh Robinson, Marian Petre
Venue: Interacting with Computers (2009)

Agile software development promotes feedback, discipline and close collaboration between all members of the development team, and de-emphasises documentation, 'big design up front' and hierarchical processes. Agile teams tend to be co-located and multi-disciplinary, and rely heavily on face-to-face communication and seemingly simple physical artefacts to support interaction. In this paper we focus on the functionality of two key physical artefacts - the story card and the Wall - which, individually and in combination, underpin the team's activity. These artefacts have two main roles - one which enables a shared understanding of requirements and one which facilitates the development process itself. We consider these roles from two perspectives: a notational perspective and a social perspective. This discussion shows how the two perspectives - the notational and the social - intertwine and are mutually supportive. Any attempt to replace these physical artefacts with alternative support for an agile team needs to take account of both perspectives, and the complex relationships between them.
Principles of Programming Languages
Authors: Gilles Dowek
Venue: Undergraduate Topics In Computer Science (2009)

The development of programming languages has radically modified our relation to language, complexity and machines. This book is an introduction to the principles around which these languages are organised imperative constructions, functional constructions, reference, dynamic data types, objects and more. Using Java as a main language, but systematically comparing it to other languages it enables the reader to understand the unifying concepts that lie beneath each particular language and provides the tools that allow the students to adapt to new programming languages.
SAT-controlled redundancy addition and removal: a novel circuit restructuring technique
Authors: Chi-An Wu, Ting-Hao Lin, Shao-Lun Huang, Chung-Yang Ric Huang
Venue: Proceedings of the 2009 Asia and South Pacific Design Automation Conference (2009)

We proposed a novel Boolean Satisfiability (SAT)-controlled redundancy addition and removal (RAR) algorithm to resolve the performance and quality problems of the previous RAR approaches. With the introduction of modern SAT techniques, such as efficient Boolean constraint propagation (BCP), conflict-driven learning, and flexible decision procedure, our RAR engine can identify 10x more alternative wires/gates while achieving 70% reduction in runtime.
Time Series Prediction with Evolved, Composite Echo State Networks
Authors: Russell Y. Webb
Venue: Proceedings of the 7th International Conference on Simulated Evolution and Learning (2008)

A framework for predictive, on-line, learning networks composed of multiple echo state networks is presented. These composite networks permit learning predictions based on complex combinations of sub-predictions and error terms. The configuration space is explored with a genetic algorithm and better performance is achieved than with hand coded solutions.
Temporal Dithering of Illumination for Fast Active Vision
Authors: Srinivasa G. Narasimhan, Sanjeev J. Koppal, Shuntaro Yamazaki
Venue: Proceedings of the 10th European Conference on Computer Vision: Part IV (2008)

Active vision techniques use programmable light sources, such as projectors, whose intensities can be controlled over space and time. We present a broad framework for fast active vision using Digital Light Processing (DLP) projectors. The digital micromirror array (DMD) in a DLP projector is capable of switching mirrors "on" and "off" at high speeds (106/s). An off-the-shelf DLP projector, however, effectively operates at much lower rates (30-60Hz) by emitting smaller intensities that are integrated over time by a sensor (eye or camera) to produce the desired brightness value. Our key idea is to exploit this "temporal dithering" of illumination, as observed by a high-speed camera. The dithering encodes each brightness value uniquely and may be used in conjunction with virtually any active vision technique. We apply our approach to five well-known problems: (a) structured light-based range finding, (b) photometric stereo, (c) illumination de-multiplexing, (d) high frequency preserving motion-blur and (e) separation of direct and global scene components, achieving significant speedups in performance. In all our methods, the projector receives a single image as input whereas the camera acquires a sequence of frames.
An Improved Selective Feedback Scheduling with a Fixed Relay
Authors: Jian Zhou, Xiaoming Hua, Baoyu Zheng
Venue: Proceedings of the 2009 WRI International Conference on Communications and Mobile Computing - Volume 02 (2009)

In a multi-user cellular network, the sum-rate capacity of a single-input single-output (SISO) downlink over flat Rayleigh fading channels asymptotically decreases to zero while the feedback threshold is large enough when Outage-Accepted Scheduling (OAS) is employed. In this paper, we consider a selective feedback scheduling and present an improved OAS where the sum-rate capacity will be promoted by a wide margin with the aid of a fixed relay. Furthermore, since the location of a relay plays an important role on the performance, the effect of different link power gains on the capacity is also evaluated. The simulation results show that the nearer to the user for the relay, the better performance gain we obtain.