nils-herrmann/clean_scirepeval huggingface dataset:
Face spoofing detection using a light field imaging framework

Face recognition systems are becoming ubiquitous, but they are vulnerable to spoofing attacks. The recently available light field cameras can be used for spoofing attack detection. In this study, the IST Lenslet Light Field Face Spoofing Database (IST LLFFSD) is proposed, consisting of 100 genuine images, from 50 subjects, captured with a Lytro ILLUM lenslet light field camera, and a set of 600 face spoofing attack images, captured using the same camera. The IST LLFFSD simulates six different types of presentation attacks, including printed paper, wrapped printed paper, laptop, tablet and two different mobile phones. This study also proposes a novel spoofing attack detection solution, based on a compact, yet effective, descriptor exploiting the colour and texture variations associated with the different directions of light captured in light field images. Extensive experiments show very effective results, with the proposed solution performing better than state-of-the-art alternatives for the face spoofing attack types considered.
Wire and patch method of moments models of coaxial to arbitrary waveguide transitions

We present a study of different techniques for the accurate characterization of coaxial to waveguide transitions. The methods use the integral equation technique to calculate the currents induced on the walls of the waveguide and on the coax probes. The modeling of the coax probes is carried out using two models, namely a thick wire model, and a surface model using triangular cells. The symmetry of the junction is exploited by using images with respect to ground planes of electric and magnetic types. Results show that the thick wire model is accurate for moderately thick probes (a//spl lambda/ = 0.025), while the rigorous surface approach must be used for probes with larger radius.
Efficient grammar processing for a spoken language translation system

A problem with many speech understanding systems is that grammars that are more suitable for representing the relation between sentences and their meanings, such as context free grammars (CFGs) and augmented phrase structure grammars (APSGs), are computationally very demanding. On the other hand, finite state grammars are efficient, but cannot represent directly the sentence-meaning relation. The authors describe how speech recognition and language analysis can be tightly coupled by developing an APSG for the analysis component and deriving automatically from it a finite-state approximation that is used as the recognition language model. Using this technique, the authors have built an efficient translation system that is fast compared to others with comparably sized language models.<<ETX>>
Post mission trajectory smoothing for the Isurus AUV

We describe an algorithm that produces a post mission estimate of the spatial evolution of the Isurus AUV. To make this post processing possible, the navigation system records on the vehicle logging system all the navigation data received during the mission execution. The data comprise the depth of the vehicle, the outputs of the tilt sensors and digital compass, the angular velocity of the propeller, as well as acoustic range measurements to a set of transponders. After mission completion, the logged data is then processed to produce the estimate of the evolution of the vehicle. The algorithm used to process this data is based on a fixed interval nonlinear stochastic smoothing scheme and produces an estimate that evolves continuously in time. For each instant of time, the post mission position estimate is based on all the information collected during the mission, as opposed to real time estimates that can only take into account past data.
Light field imaging coding: Performance assessment methodology and standards benchmarking

It is well known that the conventional ways to capture the light around us are limited and thus provide a limited user experience, notably in terms of parallax capabilities. As this has been preventing 3D systems to explode in the market, significant advances are emerging in terms of light capturing technologies among which is relevant to highlight the socalled light field cameras which capture a richer representation of the visual scene by measuring the light intensity for each direction and for each pixel position. Considering the huge amount of light intensity data involved, efficient compression becomes a must. In this context, this paper addresses the light field coding challenge by using available image coding standard solutions. With this target in mind, this paper proposes first a compression performance assessment methodology and presents after the compression performance of the direct, fully compatible usage of the main image coding standards available, notably JPEG, JPEG 2000, H.264/AVC Intra and HEVC Intra for a representative set of light field images. While the expected conclusion is that HEVC Intra is the most efficient codec, other less expected conclusions emerge.
Real-Time Polarimetric Optical High-Voltage Sensor Using Phase-Controlled Demodulation

Modern smart grid designs demand reliable sensors throughout the power delivery systems, not only to monitor the quality of the electrical energy generated by different technologies (wind, solar, hydroelectric, thermoelectric, nuclear), but also as an integral part of the generation, transmission, and distribution networks control systems. Laser polarimetric interferometry is a very suitable technique for the implementation of high sensitivity measurement instruments for various physical quantities, in particular, for high-voltage sensing. However, because the polarimetric technique is extremely sensitive to small refractive indexes variations induced in electro-optic materials by the electric field or voltage to be measured, it is also sensitive to spurious environmental quantities such as temperature variations. In this work, a novel optical voltage sensor (OVS) in conjunction with an efficient real-time method for optical phase demodulation and a PI feedback control method for signal fading suppression is demonstrated. Linearity for sinusoidal voltages having amplitudes up to 8.2 kV was evaluated, with an accuracy of 0.2% in the OVS nominal operating range. The OVS bandwidth of 5 kHz is sufficient for most electrical power quality sensor applications. Nonsinusoidal signals with high harmonic content were tested resulting in a total harmonic distortion that differed by only 0.12% from that measured by an HV reference probe. Responses to transient disturbances were also determined, showing the capability of the system to detect spikes.
A general control architecture for multiple vehicles

This paper presents a general architecture for the control of multiple vehicles based on the concept of generalized vehicle. This embodies an extension of the dynamically reconfigurable control architecture previously proposed by the authors (1994, 1995). Besides the capabilities of each vehicle inherent to the individual autonomy, the set of vehicles may be seen providing a pool of functionalists whose reconfiguration enables the emergence of a global features overcoming the single vehicle limitations. Unlike some other approaches, cooperation does not take place only at a deliberative level, but it results from a global coordination level implemented via an adequate protocol specified in the the global mission plan. The design of this architecture was driven by requirements extracted from the analysis of operational scenarios involving multiple vehicles.
A receding horizon strategy for the hierarchical control of manufacturing systems

This paper concerns the development of a hierarchical framework for the planning and scheduling of a class of manufacturing systems. In this framework, dynamic optimization plays an important role in order to define control strategies that, by taking into account the dynamic nature of these systems, minimize customized cost functionals subject to state and control constraints. The proposed architecture is composed of two hierarchical levels where a two way information flow, assuming the form of a state feedback control, is obtained through a receding horizon control scheme. At the higher level, an optimal control problem is solved by an iterative algorithm in order to define the control strategies in terms of aggregated production rates for the various subsystems. At the lower level, this control strategy is further refined in such a way that all sequences of operations are fully specified. Although this stage is strongly problem dependent an approach based on the notion of critical machine plays an important role in order to exploit the available flexibility.<<ETX>>
Large scale data collection using networks of heterogeneous vehicles and sensors

This paper presents recent developments from the Underwater Systems and Technology Laboratory in order to integrate data received simultaneously from static and free-moving wireless sensors as well as unmanned vehicles, allowing real-time access of data using ubiquitous technologies. Live data is communicated using pre-established XML data formats and using the HTTP protocol for communication. Compatible systems may both send or receive this data following a publish/subscribe design pattern. Here, we describe the architecture as well as the various systems that make part of it: operational consoles, unmanned vehicles, wireless sensor networks and drifting sensors. The entire system is evaluated by presenting results from a real-world experiment.
A Matlab/Simulink-based platform for real-time planning and execution of control techniques applied to induction motors

Simulation tools now occupy a place of particular importance in many fields of engineering. Some of these tools have come to be regarded as standard and/or as a point of departure for the replication of results obtained in scientific papers. The present paper describes the use of one of these tools, Matlab/Simulink, with a platform for real-time development and planning of control techniques for induction motors.
Classification of video segmentation application scenarios

Video analysis can be used in the context of a wide variety of applications and therefore a multiplicity of techniques has been proposed in the literature. Each of those techniques is usually devoted to solving a specific part of the complete analysis problem, unless the problem is rather simple. Typically, to be able to propose meaningful analysis solutions, the analysis problem must first be appropriately constrained, taking into account the relevant application environment. Then, complementary types of analysis techniques may have to be used in combination to achieve the desired results. This paper proposes a classification of segmentation applications into a set of scenarios, according to the different application constraints and goals. This allows an easier selection of the appropriate video segmentation solution for each specific application. Examples of segmentation solutions for the most relevant scenarios identified are presented.
Herbicide Dosage Optimization Model for Weed Control Using the Resistance Dynamics

A dynamic optimization model for weed infestation control using selective herbicide application which includes the resistance dynamics is presented. The seed bank density of the weed population and frequencies of resistant and susceptible alleles are taken as the state variables of the growing cycle. The control variable is taken as the application doses. The goal is to reduce herbicide use, maximize profit in a pre-determined period of time and minimize the environmental impacts caused by excessive use of herbicides. The optimization problem of finding the application doses is solved with a dynamic programming approach which takes into account the decreased herbicide efficacy over time due to weed resistance evolution caused by a selective pressure which varies with the applied doses. Numerical simulations for a case study with the Bidens subalternans frequent in a corn crop is presented. We used data from a green house experiment to obtain the weed response to the most widely used Atrazine herbicide. Also, the sensitivity of the optimum solution in terms of the key parameters in the seed bank dynamics that are highly influenced by environmental factors is analysed. This suggests that the optimizing solution features some robustness under a quite realistic assumption that there are imported seeds in the system.
Integrated maneuver and control design for ROV operations

The integrated maneuver and control structures for a Remotely Operated Vehicle are presented in the context of the developments of "IES - Inspection of Underwater Structures" project. The project concerns the design and implementation of an advanced low cost system for the inspection of underwater structures based on a remotely operated vehicle (ROV). First, the subsystems of the IES system are described. Second, an example of a mission is outlined. Third, the control architecture is briefly sketched and formalized. Fourth, the design of the regulation and tracking controllers for this architecture are discussed. The design uses a nonlinear dynamic surface controller (DSC). This controller is coupled with a trajectory generation system for optimal performance. The ROV model is differentially flat under mild assumptions. The trajectory generation system uses this property to produce optimal trajectories. Finally, simulation runs of DSC and PID are compared in light of model parameters uncertainty. Extensions of the work are discussed as conclusions.
An alternative to the MPEG-4 object-based error resilient video syntax

This paper addresses object-based error resilient video source coding. Specifically, the current error resilient object-based syntax used in MPEG-4 is compared to a proposed alternative syntax. Some results are presented for two MPEG-4 test sequences, and for two relevant error conditions. The results are presented in terms of two distortion measures, one for texture and one for shape.
Robust H 2 model matching from frequency domain specifications

This study addresses the problem of designing compensators for robust model matching. Firstly, the open-loop reference model (obtained, for instance, from classical frequency domain specifications), Gm(s), is recast as the product between two transfer functions GR(s) and Gr(s). A robust state feedback control law is synthesised such that an upper-bound on the ℋ2-norm of the error system between the uncertain system and Gr(s) is minimised, where the state feedback gain is determined through a convex optimisation problem over linear matrix inequality constraints. In addition, block GR(s) behaves as a series compensator in a unity feedback strategy aiming a robust steady state performance. A robust observer scheme is also proposed whenever the states are not available online to the state feedback controller. Numerical examples are presented to illustrate the approach.
Parallel DSP architecture for reconstruction of tomographic images using wavelets techniques

This paper describes a technique for reconstructing tomographic images generated by a minitomograph scanner for soil science developed by Embrapa Agricultural Instrumentation using a parallel DSP architecture with an HEPC2E board from Hunt Engineering with two TMS32OC40 processors from Texas Instruments. The software designed for visualization of bi- and tri-dimensional images uses code composer tool combined with Parallel C from 3L and Borland Builder C++. Reconstruction and interpolation tasks were distributed throughout the platform processors, using parallel algorithms in order to improve speed and processing power. The work resulted in an increase of about 15% in the system speed when compared with that reached using a classical platform at 200 MHz.
Wave Propagation and Deep Propagation for Pointer Analysis

This paper describes two new algorithms for solving inclusion based points-to analysis. The first algorithm, the Wave Propagation Method, is a modified version of an early technique presented by Pearce et al; however, it greatly improves on the running time of its predecessor. The second algorithm, the Deep Propagation Method, is a more light-weighted analysis, that requires less memory. We have compared these algorithms with three state-of-the-art techniques by Hardekopf-Lin, Heintze-Tardieu and Pearce-Kelly-Hankin. Our experiments show that Deep Propagation has the best average execution time across a suite of 17 well-known benchmarks, the lowest memory requirements in absolute numbers, and the fastest absolute times for benchmarks under 100,000 lines of code. The memory-hungry Wave Propagation has the fastest absolute running times in a memory rich execution environment, matching the speed of the best known points-to analysis algorithms in large benchmarks.
Influence of encoder parameters on the decoded video quality for MPEG-4 over W-CDMA mobile networks

The MPEG-4 standard provides error resilience tools that can significantly increase the decoded video quality when using error prone media to transmit or store the encoded data. However, the use of these tools introduces extra redundancy and overhead in the bitstreams, which means that the decoded video quality can be severely affected if no careful configuration of the relevant parameters is done while taking into account the error characteristics of the channel being used. In this paper, a videotelephony system over a W-CDMA mobile network is used to study the influence of the encoding parameters on the decoded video quality, notably its behavior and optimization.
Adaptive shape-texture intra coding refreshment for error resilient object-based video

Video encoders may use several techniques to improve error resilience. In particular, for video encoders that rely on predictive (inter) coding to remove temporal redundancy, intra coding refreshment is especially useful to stop error propagation when errors occur in the transmission or storage of the coded streams, which can cause the decoded quality to decay very rapidly. In object-based video coders, intra coding refreshment can be applied to both shape and texture data. In this paper, a novel combined intra refreshment scheme is proposed which can be used by object-based video encoders, such as MPEG-4 video encoders, to adaptively determine when the shape and texture of the video objects in a scene should be refreshed in order to maximize the decoded video quality for a certain amount of bitrate resources.
Automatic Insertion of Copy Annotation in Data-Parallel Programs

Directive-based programming models, such as OpenACC and OpenMP arise today as promising techniques to support the development of parallel applications. These systems allow developers to convert a sequential program into a parallel one with minimum human intervention. However, inserting pragmas into production code is a difficult and error-prone task, often requiring familiarity with the target program. This difficulty restricts the ability of developers to annotate code that they have not written themselves. This paper provides one fundamental component in the solution of this problem. We introduce a static program analysis that infers the bounds of memory regions referenced in source code. Such bounds allow us to automatically insert data-transfer primitives, which are needed when the parallelized code is meant to be executed in an accelerator device, such as a GPU. To validate our ideas, we have applied them onto Polybench, using two different architectures: Nvidia and Qualcomm-based. We have successfully analyzed 98% of all the memory accesses in Polybench. This result has enabled us to insert automatic annotations into those benchmarks leading to speedups of over 100x.
Integral-Equation Formulation for the Analysis of Capacitive Waveguide Filters Containing Dielectric and Metallic Arbitrarily Shaped Objects and Novel Applications

This paper presents an integral-equation formulation specialized for the analysis of capacitive waveguide circuits, which include arbitrarily shaped conducting and homogeneous magnetic/dielectric objects. The technique benefits from the symmetry of the structure by formulating a 2-D scattering problem with oblique angle of incidence, combined with the use of the parallel-plate Green’s functions. As practical applications, the paper proposes novel low-pass filter designs loaded or coated with dielectric and magnetic homogeneous materials. If the filter is properly designed, the use of these materials could improve the filter response, selectivity, or out-of-band performance, and power-handling capabilities. Some novel filter design implementations, showing these kinds of benefits, are presented for the first time in this paper. For validation, a commercial full-wave simulator is employed, showing the validity, accuracy, and computational efficiency of the novel software tool.
Correlation Noise Modeling for Efficient Pixel and Transform Domain Wyner–Ziv Video Coding

In recent years, practical Wyner-Ziv (WZ) video coding solutions have been proposed with promising results. Most of the solutions available in the literature model the correlation noise (CN) between the original frame and its estimation made at the decoder, which is the so-called side information (SI), by a given distribution whose relevant parameters are estimated using an offline process, assuming that the SI is available at the encoder or the originals are available at the decoder. The major goal of this paper is to propose a more realistic WZ video coding approach by performing online estimation of the CN model parameters at the decoder, for pixel and transform domain WZ video codecs. In this context, several new techniques are proposed based on metrics which explore the temporal correlation between frames with different levels of granularity. For pixel-domain WZ (PDWZ) video coding, three levels of granularity are proposed: frame, block, and pixel levels. For transform-domain WZ (TDWZ) video coding, DCT bands and coefficients are the two granularity levels proposed. The higher the estimation granularity is, the better the rate-distortion performance is since the deeper the adaptation of the decoding process is to the video statistical characteristics, which means that the pixel and coefficient levels are the best performing for PDWZ and TDWZ solutions, respectively.
IES an open system for underwater inspection

This paper describes the specification and design of a prototype of a low cost open system for the inspection of underwater structures based on a remotely operated underwater vehicle under the project IES. Unlike commercial approaches, a modular open system characterised by the incorporation of an on-board computer allowing for advanced control capabilities is envisaged. The control console is based on a standard PC and the tether is used only for power delivery and to establish a simple communication channel. In this project, we use advanced hybrid control techniques for sophisticated semi-autonomous operation management and control. The control architecture reuses part of the one designed for the underwater vehicle Isurus. The implementation is designed to allow for multiple sensor configurations specified as add-ins. This leads to a dynamic, scalable and flexible system that can be easily configured according to the user specifications.
IOPT-tools — A Web based tool framework for embedded systems controller development using Petri nets

The IOPT-tools Web based tool framework supports the implementation of embedded systems controllers using web-based graphical tools, starting with a graphical editor to specify controller's behavior through associated Petri-net model, complemented with model-checking and system verification tools used to debug and automatically check controller behavior correctness (helping in the detection of model flaws during the early design stages), leading to the final controller implementation code amenable to be deployed into specific platforms and using automatic code generation tools creating C code for software solutions or VHDL code for hardware descriptions.