nils-herrmann/clean_scirepeval huggingface dataset:
Novel hybrid design methodology for a surface permanent magnet synchronous motor

The present paper introduces a novel hybrid design methodology for surface permanent magnet synchronous machines. The method combines analytical and optimal design with finite element method (FEM) analysis, in order to obtain the best prototype that meets specific requirements. High efficiency and minimum cost is aimed through analytical and optimal design, while high torque capability and low cogging torque is then achieved by FEM analysis and several penalty coefficients that are introduced. A Matlab program is developed for this purpose. It implements the analytical and optimal design, calls the FEM program, draws the motor geometry, makes the finite element analysis, verifies the prototype's characteristics and if the cogging torque is too high or the total torque obtained is not satisfactory, the penalty coefficients introduced in the design code start again the whole design process. The repetitions are made until the “torque conditions” are satisfied or a maximum number of iterations is reached. The prototype is designed for the automotive air conditioning compressor drive application.
Demo: intra-frame compression for 1K-pixel visual sensors

This demonstrator illustrates the performance of our designated intra-frame video codec for low-resolution visual sensors. The encoder of the presented compression system runs on a low-power visual sensor, which captures stereo frames of 30×30 6-bit gray-scale pixels. A laptop computer is connected using a serial connection and runs the decoder in real-time, displaying the resulting visual quality, frame-rate and compression efficiency in terms of bits per pixel. Additionally, a software environment is available to the user for further evaluation of the compression performance of the codec. The user can manipulate the control parameters of the codec at will. The objective and subjective quality of the decoded video and their evolution depending on the complexity of the scene, as well as the chosen settings of the codec, are monitored in real-time.
Study of the induction machine under transient duty and steady-state as synchronized motor

The synchronized operation mode of the three-phase induction machine (synchronized induction machine - SIM) can be equated with a three-phase wound-rotor induction machine that operates under unbalanced duty. In this case, the SIM is analyzed by means of first order differential equations that contain nothing but total fluxes and the rotation angle as variable quantities. It is about an equation system that include 8 equations corresponding to the 3 stator phases, 3 rotor phases (two of the rotor phases are series-connected and form the excitation winding) and 2 movement equations. This approach offers valuable information on the instantaneous phenomena that take place inside the machine. On the basis of this information, one can adopt proper strategies concerning the most favorable moment for the connection of the windings to the supply sources in order to avoid faults such as pulling out, for instance. The hodograph of the resultant rotor flux is used as an effective tool for the evaluation SIM behavior under different duties such as transients or steady-state.
Polymer Electrolyte Fuel Cell System (PEFC) Performance Analysis

This paper presents a study of the fuel cell system performance operating at different pressure and temperature levels. A polymer electrolyte fuel cell (PEFC) is analyzed according with the possibility of using in transport applications. Therefore, it begin with the description of a parametric model of the fuel cell which has been developed using a combination between empirical and mathematics modeling techniques. This model enables to simulate fuel cells V-J curves in dependences with the stack temperature and the oxygen partial pressure. In addition, it can be used to study the influence of the gases management (pressure) on the fuel cell stack performances
Optimal Joint Source-Channel Coding using Unequal Error Protection for the Scalable Extension of H.264/MPEG-4 AVC

This paper proposes an optimized joint source-channel coding methodology with unequal error protection for the transmission of video encoded with the recently developed scalable extension of H.264/MPEG-4 AVC. The proposed methodology uses a simplified Viterbi-based search method which significantly outperforms the classical exhaustive search method in terms of computational complexity, leading to a practically applicable solution at the expense of a minimal loss of optimality. Experimental results show the effectiveness of our protection methodology and illustrate its capability to provide graceful degradation in the presence of channel mismatches.
Multiple Description Coding versus Transport Layer FEC for Resilient Video Transmission

Video content delivery is a challenging task due to its large bandwidth requirements and its sensitivity to transmission errors. In this context, simultaneously providing scalability and resilience against transmission errors is of paramount importance. Layered video coding coupled with multicast video transmission employing no feedback provides the required scalability features and reduces the network burden. However, it is not easy to provide reliability in such environments. This is crucial to mobile users as error rates on wireless links can be high. To compensate for transmission errors, redundancy must be added to the video content. This can be added at the application layer by the employed video coding system, or can be added transparently by the transport layer. In this paper, we compare the performance obtained with a scalable wavelet-based video codec that adds redundancy using multiple description coding with the equivalent system adding redundancy at the transport level, using forward error correction
Real-time texture sampling and reconstruction with wavelet filters

Currently, the use of the 2D wavelet transform in texture compression for real-time texture mapping on the GPU is limited. The main cause of this is the lack of real-time texture filtering implementations which do not require specialized hardware. This work proposes a novel system to perform 2D wavelet reconstruction and bilinear texture filtering using a high performance GPU shader. The system is able to generate a performant GLSL shader for arbitrary wavelet filter configurations. This goes beyond earlier works in the literature proposing Haar wavelet and Discrete Cosine Transform (DCT) implementations on the GPU. We analyse the shader performance and run-time complexity for several wavelet filters. The experimental results show that filters longer than Haar are deployable on the GPU while maintaining accurate texture filtering and real-time performance.
Analysis and design of a bidirectional DC-DC converter with current doubler rectifier used in Smart Grid

Distributed generation systems convert energy from solar panels, wind turbines, fuel cells etc. and supply DC/AC buses with energy of improved quality. The article describes the analysis and design of a mixed topology consisting of a phase shift converter responsible for transferring energy from the DC bus to the storage elements, and an interleaved boost converter responsible for transferring energy from the storage element to the DC bus. A new method for controlling the reverse transfer mode is developed. Also a new method for the determination of the transfer functions of the converter will be presented.
Analysis of feed currents influence on the electromagnetic forces in AC brushless motor with outer rotor

The paper proposes a method for modeling electromagnetic forces and analyzing the vibrations in synchronous motors with permanent magnets. A theoretical numerical model (based on finite element analysis of magnetic field and MATLAB/SIMULINK uses) was developed permitting study of the rotor's vibration and the effects of the motor feed on it. We propose the realization of an algorithm that allows the calculation of the current to obtain a better behavior of the motor. It is considered that the radial forces give the vibratory behavior and the ripples of the tangential force produce ripples of the torque.
Distributed barcode tracking in visual sensor networks

A novel approach for robot tracking and identification based on barcodes is proposed in this paper. The proposed system tracks robots fitted with barcodes identifying them. The system performs distributed visual processing and collaborative barcode tracking, whereby the nodes exchange processed visual information with appropriate neighboring nodes, informing them about incoming targets. The proposed tracking system is deployed on a visual sensor network (VSN) based on the Raspberry Pi. Its practical realization includes various components that handle real-time collaborative tracking, streaming, communication, configuration, management, monitoring, and deployment. The proposed system is able to efficiently and accurately track barcodes in real time. Complexity modeling demonstrates that the proposed distributed system brings substantial complexity reductions compared to a system of independently operating cameras. Experimental results demonstrate that the proposed system can track multiple barcodes in real time with an accuracy of less than 1 centimeter.
A design method for EMI filters mitigating perturbations generated by a PWM converter

The paper deals with the general problem of EMI filters used for harmonic perturbations generated by the PWM converters. In particular - are presented the design aspects and experimental results for EMI filter connected between the active filter and the low voltage network. For a typical solution of three phase EMI filter, a FEM modeling of magnetic circuit is performed. For the designed filter, the measured transfer characteristics, both in differential and common mode are given. Are also presented the resistive and inductive drops on the load connected at one of the phases.
Accurate detection of coronary arteries with the continuous wavelet transform

The authors propose a multi-scale detection scheme of the vessels borders by means of the continuous wavelet transform. The Canny's (1986) performance parameters are derived for Mallat's (1992) wavelet based edge detection operator. The authors take the scale dependent behaviour of these parameters into account to design an algorithm that optimally combines the multiscale information. Evaluation of the algorithm accuracy is obtained on 4 vessel phantoms of different diameters. The authors compare the computer determined diameters to the actual diameters, the correlation coefficient is in the range 0.93-0.99 for different types of wavelets, which proves the ability of the method to accurately detect edges in the presence of noise.
Scalable L-Infinite Coding of Meshes

The paper investigates the novel concept of local-error control in mesh geometry encoding. In contrast to traditional mesh-coding systems that use the mean-square error as target distortion metric, this paper proposes a new L-infinite mesh-coding approach, for which the target distortion metric is the L-infinite distortion. In this context, a novel wavelet-based L-infinite-constrained coding approach for meshes is proposed, which ensures that the maximum error between the vertex positions in the original and decoded meshes is lower than a given upper bound. Furthermore, the proposed system achieves scalability in L-infinite sense, that is, any decoding of the input stream will correspond to a perfectly predictable L-infinite distortion upper bound. An instantiation of the proposed L-infinite-coding approach is demonstrated for MESHGRID, which is a scalable 3D object encoding system, part of MPEG-4 AFX. In this context, the advantages of scalable L-infinite coding over L-2-oriented coding are experimentally demonstrated. One concludes that the proposed L-infinite mesh-coding approach guarantees an upper bound on the local error in the decoded mesh, it enables a fast real-time implementation of the rate allocation, and it preserves all the scalability features and animation capabilities of the employed scalable mesh codec.
Open access database for experimental validations of holographic compression engines

Holography allows for both the recording and reproduction of wavefields of light, and is thereby able to fully capture the three-dimensional structure of objects. The appearance of the object will change according to the position and orientation of the viewer, providing an immersive experience as if objects are actually present. Moreover, holograms have many applications in metrology such as microscopy and interferometry. Because holograms represent interference patterns, they possess significantly different signal properties from natural photography and video; this will make conventional image encoders perform sub-optimally on holograms. Therefore, new data compression techniques have to be evaluated for this type of data. One important requirement for comparing and evaluating various codecs is to have reference holograms which are publicly available. For this purpose, we have set up an open public database containing a set of computer-generated holograms. Furthermore, we evaluate the performances of two JPEG 2000-based coders, which were modified to better cope with holographic data.
Lossy-to-lossless screen content coding using an HEVC base-layer

This paper presents a novel High Efficiency Video Coding (HEVC) based screen content coding scheme providing lossy-to-lossless compression support. The paper follows a two-layer design approach which allows for backward compatibility with the conventional HEVC standard for the base-layer and yields lossless compression when decoding the enhancement-layer. The system employs Golomb based binarization and context-based arithmetic coding to efficiently encode the enhancement-layer. Performance evaluations using 4:4:4 screen content sequences are carried out. The results show that the proposed system substantially outperforms lossless intra- HEVC and single-layer JPEG-LS.
MESHGRID - a compact, multi-scalable and animation-friendly surface representation

MESHGRID is a novel, compact, multi-scalable and animation-friendly surface representation method, which has been introduced in MPEG-4. The MESHGRID representation attaches a description of the "global connectivity" between the vertices on the object's surface (i.e. the 3D connectivity wireframe) to a regular 3D grid of points (i.e. the reference-grid). The 3D connectivity wireframe is efficiently encoded by using a new type of 3D extension of Freeman chain-code. MESHGRID does not explicitly store the polygons of the surface, since the 3D connectivity wireframe has particular connectivity properties allowing for the unambiguous derivation of the triangulation. The reference-grid is a smooth vector field defined on a regular discrete 3D space. This grid is efficiently compressed by using an embedded 3D wavelet-based multi-resolution intra-band coding algorithm. MESHGRID allows for three types of scalability in both view-dependent and view-independent scenarios: resolution scalability, shape precision, and vertex position scalability. Furthermore, in addition to the classical vertex-based animation, MESHGRID supports specific animation capabilities, such as rippling effects and reshaping on a hierarchical basis of the regular reference-grid and its attached vertices.
On the optimality of embedded deadzone scalar-quantizers for wavelet-based L-infinite-constrained image coding

In wavelet-based L/sub /spl infin//-constrained embedded coding, the bit-stream is truncated at the bit-rate that corresponds to a guaranteed, user-defined distortion bound. The letter analyzes the optimality of embedded deadzone scalar-quantizers for high-rate L/sub /spl infin//-constrained scalable wavelet-based image coding. A rate-distortion model applicable to the family of embedded deadzone scalar-quantizers is derived and experimentally validated. Conclusions are drawn regarding the optimal subband-quantizer instantiations. The optimal quantizers are employed in a coding algorithm that retains the coding performance and the flexibility options of wavelet-based codecs while allowing for a fully embedded L/sub /spl infin//-oriented bit-stream.
Visually lossless screen content coding using HEVC base-layer

This paper presents a novel two-layer coding framework targeting visually lossless compression of screen content video. The proposed framework employs the conventional HEVC standard for the base-layer. For the enhancement layer, a hybrid of spatial and temporal block-prediction mechanism is introduced to guarantee a small energy of the error-residual. Spatial prediction is generally chosen for dynamic areas, while temporal predictions yield better prediction for static areas in a video frame. The prediction residual is quantized based on whether a given block is static or dynamic. Run-length coding, Golomb based binarization and context-based arithmetic coding are employed to efficiently code the quantized residual and form the enhancement-layer. Performance evaluations using 4:4:4 screen content sequences show that, for visually lossless video quality, the proposed system significantly saves the bit-rate compared to the two-layer lossless HEVC framework.
L1-optimized linear prediction for light field image compression

The advent of consumer-level plenoptic cameras has sparkled the interest towards the design of efficient compression techniques for light field images. State-of-the-art compression systems such as HEVC prove to be inefficient when directly applied on this type of data due to the inherent spatial discontinuities among neighboring microlens images. In this paper, a novel light field image compression system is proposed. The disk-shaped pixel clusters corresponding to each microlens in the light field image are efficiently predicted based on the neighboring disks. In this context, an optimized linear prediction design based on L1 minimization of the residuals is proposed. K-means clustering is employed on training data in order to determine the optimized set of predictors. The experimental results on an extensive set of light field images demonstrate that the proposed coding scheme yields an average of 2.93 dB and 3.22 dB gain in PSNR, and 52.67% and 57.27% average rate savings compared to HEVC and JPEG2000 respectively.
The Rate Loss in Binary Source Coding with Decoder Side Information

Motivated by the correlation channel modeling problem in practical applications, such as distributed video coding, we study the binary source coding of a uniform source with side information, under asymmetric correlation channel assumptions. First, we consider the case where side information is available to both the encoder and decoder, and give an analytical formula for the rate-distortion bound. Then, we consider the side information to be available only to the decoder and present the derivation of the associated Wyner-Ziv rate-distortion bound. Most importantly, we characterize the evolution of the rate-loss suffered by Wyner-Ziv coding, for all possible binary asymmetric correlation channels.
Thermal stresses analysis of current path from return circuit of electric traction

The traction current is returning to the supply source crossing the return circuit to the 25 kV single-phase AC power source. The return circuit consists of the running rails, which are connected by conductors to the joint coils terminals, and the return feeder to the traction substation. The connecting conductors (connection ropes) are subjected to thermal stresses due to the intense currents which are crossing them. In order to determine the thermal stresses of the connecting ropes between running rails and joint coils and how it can influence the return circuit, different tests were performed to analyze the abnormal situations which can occur from time to time.
A new method for complete-to-overcomplete discrete wavelet transforms

Overcomplete discrete wavelet transforms (ODWT) are used in a number of applications because they provide shift invariance, a property extremely useful in wavelet-based image processing and video coding. In this paper, we propose a new construction of the ODWT starting from the subbands of the critically sampled (complete) DWT. The most straightforward application of our theory is scalable video coding with in-band prediction, for which it has been shown that the proposed method achieves lower complexity.
Bitplane intra coding with decoder-side mode decision in distributed video coding

While distributed video coding (DVC) has emerged as a new video coding paradigm, the compression performance of current systems is still low compared to conventional solutions such as H.264/AVC. While the latter uses many coding modes and an efficient mode decision strategy for choosing the best mode, in DVC, only a limited number of modes has been developed so far. Since encoder-side mode decision in DVC increases encoder's complexity, in this paper, we introduce decoder-side mode decision choosing between bitplane WZ coding and bitplane intra coding. This strategy proves to be efficient, delivering rate gains up to 22% over DISCOVER, without increasing the complexity at the encoder.
Statistical L-infinite distortion estimation in scalable coding of meshes

This paper investigates the novel concept of local error control in arbitrary mesh encoding, and proposes a new L-infinite mesh coding approach implementing this concept. In contrast to traditional mesh coding systems that use the mean-square error as distortion measure, the proposed approach employs the L-infinite distortion as target distortion metric. In this context, a novel wavelet-based L-infinite-constrained coding approach for meshes is proposed, which ensures that the maximum local error between the original and decoded meshes is lower than a given upper-bound. Additionally, the proposed system achieves scalability in L-infinite sense, that is, the L-infinite distortion upper-bound can be accurately estimated when decoding any layer from the input stream. Moreover, a distortion estimation approach is proposed, expressing the L-infinite distortion in the spatial domain as a statistical estimate of quantization errors produced in the wavelet domain. An instantiation of the proposed L-infinite coding approach is demonstrated for MESHGRID, which is a scalable 3D object coding system, part of MPEG-4 AFX. The proposed L-infinite coding approach guarantees that the maximum error is upper-bounded, it enables a fast real-time implementation of the rate-allocation, and it preserves all the scalability features and animation capabilities of the employed scalable mesh codec.
Rate-distortion optimized composition of HEVC-encoded video

This paper proposes a global rate control scheme to maximize the overall encoding quality of a network-based video composition system. The input video sources are encoded using HEVC. The rate-distortion function for each input video source is modelled based on the known PSNR and bitrates at two quantization points and the R-λ model in HEVC. By solving an R-D optimization problem, the proposed scheme is able to optimally allocate rate for each video source and maximize the overall video quality of the composition with respect to the global bandwidth budget. We have evaluated the proposed scheme against a coding scheme where the same quantization parameter (QP) is employed for all video sources. The experimental results show that up to 14.3% average bitrate reduction is achieved by the proposed rate allocation scheme.