nils-herrmann/clean_scirepeval huggingface dataset:
Reversible DCT-based lossy-to-lossless still image compression

This paper presents a novel still image compression scheme that extends the traditional JPEG standard with lossy-to-lossless compression support. The system follows a two-layer design approach which allows for backward compatibility with the conventional JPEG standard for the base layer and provides lossless compression when decoding the enhancement layer. The system employs several coding tools, including quadtree coding, spatial domain prediction, reversible discrete cosine transforms, and context-based arithmetic coding to efficiently encode losslessly the enhancement layer. Performance evaluations using a standard JPEG set of images show that the proposed system yields similar lossless compression performance to the state-of-the-art single-layer JPEG-LS standard while providing quality scalability and a JPEG-compatible base layer at the same time.
Overlapped Block Motion Estimation and Probabilistic Compensation with Application in Distributed Video Coding

It has been recently demonstrated that, in distributed video coding (DVC) side-information dependent modeling of the correlation channel brings significant performance gains over side-information independent assumptions. In this letter, we present a novel technique enabling advanced side-information dependent estimation of the correlation channel at the decoder starting from a very coarse knowledge of it. The proposed technique triggers the design of a spatial-domain DVC codec which enables the suppression of the feedback channel. Experimental results show that the proposed codec achieves similar performance compared to the state-of-the-art in transform-domain Wyner-Ziv video coding while still operating at a fraction of its encoding complexity.
Design and finite element analysis of high-density torque induction motor for traction applications

The paper presents the design and FEM simulation of a novel induction motor intended as a specialized drive for electric traction and/or airborne propulsion applications. Several particular requirements related to the size, weight and dynamics did rise non-conventional challenges and therefore a less-than classical approach have been considered. The proposed solution consists in a combination of an external rotor mated with an internal stator with ring coils. Furthermore, the coils arrangement may be reconfigured on-the-fly, allowing operation with two distinct synchronous speeds (different number of poles), solution which largely fulfills all the requirements.
FEM-based analysis on the operation of three-phase induction motor connected to six-phase supply system: Part 1 — Operation under healthy conditions

The paper presents a comparative analysis of a three-phase induction motor that operates connected to the industrial supply system and separately to a six-phase supply source, as well. The design of the electric machine is made in such a way to fit for both situations. The six-phase supply, which is composed of two distinct three-phase systems, was configured for two cases: 30° and 60° phase shifting between the systems, respectively. The analysis is based on FEM simulations under steady-state and transient conditions.
Evaluation of a quincunx wavelet filter design approach for quadtree-based embedded image coding

We study the compression performance of the quincunx discrete wavelet transform (DWT) and we compare it with the dyadic DWT in terms of rate-distortion. The 2D non-separable quincunx wavelet filters are designed by making use of the transformations of variables technique of Tay and Kingsbury (1993) starting from the 1D biorthogonal (9,7)-taps filters. The applied transformation functions are respectively based on the Kaiser and Chebyshev windows, and on the Lagrange halfband filters. The novelties of this work are in the evaluation of these filters for image compression and the usage of an embedded coder based on the quadtree approach for coding the quincunx subbands.
Electrostatic treatment of bean seeds

The classical methods of seed treatment make use of chemical substances, which are either expensive or harmful for the soil. This paper aims to demonstrate that exposure to the action of a high-intensity electric field can be an effective substitute for chemical agents. Experiments were carried out on infected bean seeds. Under normal conditions (no treatment), only about 30% of a reference sample of such seeds germinated. Other samples were subjected to AC electric fields, ranging from 2 to 16 kV/cm. The exposure time ranged from 1 s to 30 s. In the optimum laboratory test, more than 99% of the seeds germinated. The weight of the resulted plants was significantly superior to that of the beans developed from nontreated seeds. The field tests proved the efficiency of this method, which could be successfully employed for the prevention or treatment of various seed-transmitted diseases of plants. The automated seed treatment installation proposed in this paper consists of a plate-type capacitor, supplied from a 75 kV AC generator. Special devices ensure the rapid transfer of the material to and from the seed treatment cell. The method and the installation of seed treatment have been patented.
Error protection of scalable soures: A comparative analysis of Forward Error Correction and Multiple Description Coding

In this paper we examine the Distortion-Rate (D-R) performance of two competing approaches for error-resilient transmission of scalable sources over error-prone packet-based memoryless channels. Thereby, we consider scalable Joint Source-Channel Coding (JSCC) based on Forward Error Correction (FEC) and scalable Multiple Description Coding (MDC). Our analysis considers memoryless Gaussian input sources encoded using source coders that can achieve theoretical performance bounds. This input source model is independent of actual implementations of the source coders and therefore allows drawing conclusions on the theoretical D-R performance of both approaches. Our comparative analysis indicates that in matched channel conditions, the use of an optimized FEC-based JSCC approach yields significantly better error resilience compared to the use of scalable MDC. Moreover, it is shown that in mismatched conditions a scalable JSCC approach has the potential to outperform a scalable MDC approach.
On the side-information dependency of the temporal correlation in Wyner-Ziv video coding

Current models in Wyner-Ziv video coding consider the temporal correlation noise to be side-information independent (SII). This paper goes beyond this assumption and proposes a novel model, of which the parameters are side-information dependent (SID). The proposed model is experimentally validated showing remarkable accuracy improvement over the conventional SII model. Moreover, a novel SID technique for the accurate estimation of the correlation channel in video is introduced. The proposed technique enables the design of a novel pixel-domain Wyner-Ziv video coding system operating without a feedback channel. Preliminary experimental results show that the proposed codec achieves superior performance compared to the state-of-the-art in pixel-domain Wyner-Ziv coding.
Comparative finite element analysis of two PM fractional slot machines with 9/8 and 9/10 structure

This paper presents a FEM-based analysis of two permanent magnet fractional slot machines that have the same stator structure with 9 slots but a different number of rotor poles, which is 8 and 10 respectively. The results have to point out the advantages and drawbacks of each structure. Specific electromagnetic quantities have been investigated such as flux density and back emf, but also cogging torque and output characteristics under generating and motoring.
Achievability of the rate-distortion function in binary uniform source coding with side information

In this work we consider asymmetric correlation channels and focus on the achievability of the rate-distortion function when the source is binary uniform. This lies in contrast with conventional symmetric correlation channel models employed in the literature. The rate-distortion function for binary source coding with correlated side information is expressed as a function of an auxiliary random variable with an alphabet size smaller or equal to three. Complementing our recent findings on the problem, we propose a numerical analysis of the differences between assuming binary and ternary auxiliary variables in the derivation of the rate distortion bound. We also show that, even if the proposed bound does not admit an analytical expression, it always admits a unique solution.
On the optimality of embedded deadzone scalar-quantizers for wavelet-based L-infinite-constrained image coding

Several methods for L/sub /spl infin//-distortion constrained compression have been proposed that target a set of fixed reconstruction-error bounds. Recently, a wavelet-based L/sub /spl infin//-constrained embedded image-coding technique was proposed that guarantees the required distortion bound while retaining the coding performance and scalability option state-of-the-art wavelet-based L/sub /spl infin//-oriented codecs. The optimality of embedded deadzone scalar-quantizers for high-rate L/sub /spl infin//-constrained scalable wavelet-based coding of images was analyzed. The optimal quantizers were employed in a coding algorithm that outperforms embedded L/sub /spl infin//-oriented wavelet-coders in terms of maximum absolute error. The algorithm was briefly described and coding results were provided.
About monitoring of joint coils from electric traction railway

The general structure of the electric traction system highlights the complexity and diversity of electrical equipment from the power supply. The return circuit, part of electric traction railway, consists of the running rails, the joint coils and the return feeder to the traction substation. Monitoring of the electrical equipment, existent in the electric traction railway, is a newest concept. The paper presents aspects about monitoring of some parameters of joint coils used in electricity supply systems from traction electric. Also, it is presented the monitored parameters considered important for knowledge of technical condition of a joint coil, in normal situation and in case of abnormal operating conditions, when are comparing them with similar records considered of reference. Data acquiring and them analysis was performed with an acquisition card, respectively by using a software application developed in LabVIEW programming environment.
Efficient hash-driven Wyner-Ziv video coding for visual sensors

Recent advances in wireless visual sensor technology, have been calling for innovative architectures realizing efficient video coding under stringent processing and energy restrictions. Driven by profound findings in network information theory, Wyner-Ziv video coding constitutes a suitable paradigm for video sensor networks. This work presents a novel hash-driven Wyner-Ziv video coding architecture for visual sensors, which coarsely encodes a low resolution version of each Wyner-Ziv frame to facilitate accurate motion-compensated prediction at the decoder. The proposed method for side-information generation comprises hash-based multi-hypothesis pixel-based prediction. Once critical Wyner-Ziv information is decoded, the derived dense motion field is further enhanced. Experimental validation illustrates that the proposed hash-driven codec achieves significant compression gains with respect to state-of-the-art Wyner-Ziv video coding, even under demanding conditions.
FEM-based analysis on the operation of three-phase induction motor connected to six-phase supply system: Part 2 — Study on fault-tolerance capability

Based on the fact that the three-phase induction machine proves higher performance under six-phase supply, which was demonstrated in Part 1 of the paper, this work investigates the fault-tolerance capability of the six-phase structure with asymmetrical configuration (30° phase shifting both for space and time conditions). It is taken into discussion the cut-off of one, two and three phases respectively. The study is carried through FEM simulations under steady-state and transient conditions.
Special three-phase to multiple different polyphase systems electric transformer

In this paper a special electric transformer which allows achieving multiple polyphase systems (two-phase, five-phase and six-phase) from the three-phase power grid, using different connection schemes, is presented. The purpose of such an electric transformer is to offer the possibility of easily obtain different multiphase electric systems from the available three-phase power system, in electric machines laboratory for supplying polyphase motor drives, lately used on a large scale and variety. Connection schemes, phasor diagrams and turn ratios along with experimental data acquisitions are illustrated.
Multiterminal Source Coding With Copula Regression for Wireless Sensor Networks Gathering Diverse Data

Efficient data compression at a low processing and communication cost is a key challenge in wireless sensor networks. In this paper, we propose a novel multiterminal source code design, which, contrary to prior work, utilizes both the intra- and the inter-sensor data dependences. The former is exploited by applying simple differential pulse-code modulation followed by arithmetic entropy coding at each distributed encoder. This approach limits the encoding complexity and provides for a flexible design that adapts to the variations in the number of operating sensors. Moreover, we propose a regression method applied at the joint decoder, which aims at leveraging the inter-sensor data dependences. Unlike existing work that focuses on homogeneous data types, the proposed method makes use of copula functions, namely, a statistical model that captures the dependence structure amongst heterogeneous data types. Experimentation using real sensor measurements-taken from the Intel-Berkeley database-shows that the proposed system achieves significant compression improvements compared with the state-of-the-art multiterminal and distributed source coding schemes.
A new quantization algorithm for a wavelet compression scheme of coronary angiograms

New methods for image compression which are able to store and retrieve efficiently the images produced by a digital angiographic unit are needed for clinical use. Currently discrete cosine transform (DCT) based compression schemes (i.e. JPEG, MPEG) generate unacceptable block artefacts in coronary angiograms at high compression ratios, because of the block coefficients quantization. We propose a wavelet compression algorithm that overcomes fundamentally this drawback. Using a set of 40 coronary angiograms, we evaluated the method by analyzing several image quality factors: peak signal to noise ratio, compression ratio, maximum absolute difference and mean difference of gray levels and subjective evaluation. At the same compression ratio, the proposed technique outperforms the JPEG method in image quality presentation.
Spatio-Temporally Consistent Color and Structure Optimization for Multiview Video Color Correction

When compared to conventional 2-D video, multiview video can significantly enhance the visual 3-D experience in 3-D applications by offering horizontal parallax. However, when processing images originating from different views, it is common that the colors between the different cameras are not well- calibrated . To solve this problem, a novel energy function -based color correction method for multiview camera setups is proposed to enforce that colors are as close as possible to those in the reference image but also that the overall structural information is well-preserved. The proposed system introduces a spatio-temporal correspondence matching method to ensure that each pixel in the input image gets bijectively mapped to a reference pixel. By combining this mapping with the original structural information, we construct a global optimization algorithm in a Laplacian matrix formulation and solve it using a sparse matrix solver. We further introduce a novel forward-reverse objective evaluation model to overcome the problem of lack of ground truth in this field. The visual comparisons are shown to outperform state-of-the-art multiview color correction methods, while the objective evaluation reports PSNR gains of up to 1.34 dB and SSIM gains of up to 3.2%, respectively.
Fully scalable intraband coding of wavelet-decomposed 3D meshes

In this paper, a scalable intraband wavelet coding technique for semi-regular topology surface meshes is proposed. The choice of an intraband codec design is justified through an information theoretic analysis of the statistical dependencies between the wavelet coefficients resulting from a wavelet-based decomposition of the input 3D mesh. The bitstream produced by the proposed codec is both resolution and quality scalable. This lies in contrast with well-known zero-tree based interband coding techniques that only support quality scalability. The experimental results show that, on average, the proposed codec outperforms the state-of-the-art zero-tree based interband codec in rate-distortion sense when using the 2 L norm as target distortion metric.
Side-Information-Dependent Correlation Channel Estimation in Hash-Based Distributed Video Coding

In the context of low-cost video encoding, distributed video coding (DVC) has recently emerged as a potential candidate for uplink-oriented applications. This paper builds on a concept of correlation channel (CC) modeling, which expresses the correlation noise as being statistically dependent on the side information (SI). Compared with classical side-information-independent (SII) noise modeling adopted in current DVC solutions, it is theoretically proven that side-information-dependent (SID) modeling improves the Wyner-Ziv coding performance. Anchored in this finding, this paper proposes a novel algorithm for online estimation of the SID CC parameters based on already decoded information. The proposed algorithm enables bit-plane-by-bit-plane successive refinement of the channel estimation leading to progressively improved accuracy. Additionally, the proposed algorithm is included in a novel DVC architecture that employs a competitive hash-based motion estimation technique to generate high-quality SI at the decoder. Experimental results corroborate our theoretical gains and validate the accuracy of the channel estimation algorithm. The performance assessment of the proposed architecture shows remarkable and consistent coding gains over a germane group of state-of-the-art distributed and standard video codecs, even under strenuous conditions, i.e., large groups of pictures and highly irregular motion content.
Multiple synchronous detection method for measuring non-linear and static resistance

The analyze of the stationary regime of non-linear circuits excited with periodical signals is difficult, on one hand because into the general solutions of the differential non-linear equation system the components of the stationary regime can not be separated, and on the other hand because of the different structure of the response signal and of the excitation signal. Characteristically for the non-linear element is the fact that between the input parameter and the output parameter do not exist a proportionality relation. A particular case is the non-linear resistance. This circuit element is defined by the fundamental terms of the trigonometric series of voltage and current. The characteristics of non-linear resistance are approximated by a polynomial and the paper presents a method for determining the polynomial's coefficients to compute the non-linear and the static resistance, corresponding to a periodical current excitation applied to the non-linear resistor, by the technique of multiple synchronous detection. In the second part of the paper is presented an instrument for measurement in virtual technique the non-linear and static resistance, implemented in LabVIEW graphical programming software. The solution allows a quick and convenient measurement of these important circuit components, together with an appropriate graphical representation. The performances of this measurement technique are: easiness of design, flexibility of interconnection of signal processing software blocks, clear presentation of the results in the front panel of the instrument and, last but not least, accuracy of the measurement data software processing.
Considerations regarding infrared thermal stresses monitoring of electrical equipment

The paper aim is to analyze the way in which the electrical load influences the infrared thermal images of the thermal stresses of electrical equipment determined by using infrared thermography devices. In order to obtain a reliable result of the infrared investigations several conditions must be accomplished, such as good definition of the correction parameters and choosing the optimal environmental conditions to perform the investigation. The paper presents the way in which it is corrected the electrical load of the collector busbar system after the thermal image was captured in order to determine its thermal stresses. On an experimental setup there were performed several attempts to determine the thermal stress of a portion from a HV (high voltage) collector busbar system which has two ramifications with the same electrical loads.
Didactic platform for the study of hybrid wind-hydro power plants

This paper presents a study regarding the implementation of a Platform for the studying of hybrid wind-hydro power plants. The hybrid wind-hydro power plant uses the storage capacity of hydro power plant to store the wind energy in the form of hydro-energy of water when the wind exists but lacks the electric load. The Didactic Platform is to be placed in a building belonging to the Technical University of Cluj-Napoca. A wind turbine will be placed on the top of the building, which place being favourable regarding the average wind speed. The wind energy will be converted in electric energy, which will be stored in an electric accumulator battery. This energy is similar with the energy stored in a superior water basin of a hydro-power plant. The hydropower plant will be further simulated by a hydro-turbine, operating in closed circuit with an electric pump and a lower water basin. From the accumulators the stored wind energy will be converted in water pressure by means of an inverter and an electric pump and further again in electric energy by means of hydro-generator. Such an arrangement is combined with measuring devices: anemometer, electric energy measurements devices, flow-rate and pressure water measuring devices, which allows evaluating the performances of the simulated hybrid wind-hydro power plant. The paper presents the design of this didactic platform together with an estimation cost.
Fully-scalable wavelet video coding using in-band motion compensated temporal filtering

This paper presents a novel fully-scalable wavelet video coding scheme that performs efficient open-loop motion compensated temporal filtering (MCTF) in the wavelet domain (in-band). Unlike the conventional spatial-domain MCTF (SDMCTF) schemes, which apply MCTF on the original image data and then encode the residual image using a critically-sampled wavelet transform, the framework presented here applies the in-band MCTF (IBMCTF) after the discrete wavelet transform (DWT) is performed in the spatial dimensions. To overcome the inefficiency of motion estimation (ME) in the wavelet domain, a complete-to-overcomplete DWT (CODWT) is performed. The proposed framework provides improved quality (SNR) and temporal scalability as compared with existing in-band closed-loop temporal prediction schemes with ODWT and improved spatial scalability as compared to SDMCTF. We present a thorough comparison between SDMCTF and the proposed IBMCTF in terms of coding efficiency and scalability. Furthermore, we describe several extensions that enable the filtering of the various bands to be performed independently, based on the resolution, sequence content, complexity requirements and desired scalability.