nils-herrmann/clean_scirepeval huggingface dataset:
An immersive virtual environment for DT-MRI volume visualization applications: a case study

We describe a virtual reality environment for visualizing tensor-valued volumetric datasets acquired with diffusion tensor magnetic resonance imaging (DT-MRI). We have prototyped a virtual environment that displays geometric representations of the volumetric second-order diffusion tensor data and are developing interaction and visualization techniques for two application areas: studying changes in white-matter structures after gamma-knife capsulotomy and pre-operative planning for brain tumor surgery. Our feedback shows that compared to desktop displays, our system helps the user better interpret the large and complex geometric models, and facilitates communication among a group of users.
An Algorithm For Estimating Rotation Speed From Projections

A synthetic aperture radar (SAR) is a microwave radar system mounted on a moving platform, such as an aircraft or a satellite, to image strips or pitches of terrain. It can also be used as ground-based radar to image orbiting objects. It has been shown that the formulation of the SAR is equivalent to the backprojection method commonly used in the computer-aided tomography (CAT). More specifically, if a chirp signal is transmitted by the radar, the demodulated returned signal at each angle approximates a piece of the onedimensional Fourier transform of the central projection of the object at the corresponding angle. According to the Fourier-slice theorem, this in turn equals to a slice of the threedimension Fourier transform of the imaged object. Hence, in order to accurately reconstruct the object, it is important to first know the relative position of the antenna and the object at every transmitting/receiving time instance. Equivalently, in the scenario of a rotating object, we are interested in estimating the angular velocity. In this paper, we present a new algorithm for estimating the rotation speed of an point source which is orbiting around a fixed axis. There are three phasles in our algorithm. In the first phase, the preprocessing step, we use a priori information to obtain a range of possible rotation speeds. Accordingly, we can reconstruct images using different rotation speeds in the second phase. In the third phase. We compute the variance of the distribution of each of the reconstructed point source. Presumably, the ideally reconstructed image would have smallest variance, while all the other images will have larger variances due to the non-linear effects induced during the reconstruction phase. We have applied this algorithm to a number of simulated data and satisfactory results are obtained. With this algorithm, we can estimate the rotation speed with error less than 2% in more than 85% of the cases. The average estimation error is less than 0.5%, and the largest error is only 5.7%.
A low complexity deterministic algorithm for the antenna/user selection in multi-antenna systems

When a MIMO wireless channel matrix H is rank deficient, it is often required to select a submatrix Hp ϵ H such that the columns of Hp lie close to the optimal subspace that constructs H. Main motivation for the selection of Hp is to gain the same spectral efficiency benefits as that of H, but at a lower computational and RF hardware cost. In this contribution, we first present an analogy between the antenna and user selection problems. Secondly, a matrix volume maximization criterion that is applicable to both problems have been presented. We have proposed a low complexity deterministic algorithm for the selection of antennas/users such that the volume of Hp is maximum. We have shown that under particular channel propagation setup, smaller subsets can provide the same spectral efficiency as that of the full MIMO channel. We used a 3D extension of the WINNER channel model at center frequency 2.53 GHz to evaluate the performance of the proposed algorithm.
Community Detection with Edge Content in Social Media Networks

The problem of community detection in social media has been widely studied in the social networking community in the context of the structure of the underlying graphs. Most community detection algorithms use the links between the nodes in order to determine the dense regions in the graph. These dense regions are the communities of social media in the graph. Such methods are typically based purely on the linkage structure of the underlying social media network. However, in many recent applications, edge content is available in order to provide better supervision to the community detection process. Many natural representations of edges in social interactions such as shared images and videos, user tags and comments are naturally associated with content on the edges. While some work has been done on utilizing node content for community detection, the presence of edge content presents unprecedented opportunities and flexibility for the community detection process. We will show that such edge content can be leveraged in order to greatly improve the effectiveness of the community detection process in social media networks. We present experimental results illustrating the effectiveness of our approach.
Alternate Poles Wound Flux-Switching Permanent-Magnet Brushless AC Machines

Flux-switching permanent-magnet (FSPM) brushless machines have emerged as an attractive machine type by virtue of their high torque densities, simple and robust rotor structure, and the fact that permanent magnets and coils are both located on the stator. Both 2-D and 3-D finite element analyses are employed to compare the performance of a conventional all poles wound (double-layer winding) topology with that of three modular alternate poles wound (single-layer winding) topologies, in terms of output torque, flux-linkage, back EMF, and inductances. It is shown that the FSPM machine can be designed in this way without incurring a significant performance penalty, but that some degree of rotor skewing or a variation in stator and rotor pole combination may be required in order to maintain a sinusoidal back-EMF waveform and reduce the torque ripple. Experimental validation is reported for both conventional all poles wound and alternate poles wound FSPM machine topologies.
Evaluating dynamic maximum power point tracking with variable solar irradiance

Photovoltaic (PV) plant performance, among many factors, depends on inverter tracking of the maximum power point and its energy conversion efficiency. For a given PV array, under certain environmental conditions, the energy yield depends on the inverter's dynamic response for maximum power point tracking (MPPT) with highly variable array output. This paper describes the theoretical irradiance test profile proposed in a European Norm Standard (EN 50530:2010) for inverter Dynamic MPPT efficiency evaluation. Example test results from two inverters are included. This paper also reports some discrepancy in the standard test profile by comparing the required test environment with high resolution measured solar irradiance ramp rate data for a South-East and a Western part of USA.
Discriminative estimation of 3D human pose using Gaussian processes

In this paper, we present an efficient discriminative method for human pose estimation. This method learns a direct mapping from visual observations to human body configurations. The framework requires that the visual features should be powerful enough to discriminate the subtle differences between similar human poses. We propose to describe the image features using salient interest points that are represented by SIFT-like descriptors. The descriptor encode the position, appearance, and local structural information simultaneously. Bag-of-words representation is used to model the distribution of feature space. The descriptor can tolerate a range of illumination and position variations because it is computed on overlapped patches. We use Gaussian process regression to model the mapping from visual observations to human poses. This probabilistic regression algorithm is effective and robust to the pose estimation problem. We test our approach on the HumanEva data set. Experimental results demonstrate that our approach achieves the state of the art performance.
A temporal logic approach to the specification of reconfigurable component-based systems

We propose a formal specification language for dynamically reconfigurable component-based systems, based on temporal logic. The main aim of the language is to allow one to specify behaviours of component-based systems declaratively, with special emphasis on behaviours in which the architectural structure of the system changes dynamically. Due to the semantics and organisation of our language, it is straightforward to hierarchically build reconfigurable systems in terms of subsystems and basic component parts, and reason about them within the language. Despite its expressive power, the language is rather simple.
Contractor selection criteria: a cost-benefit analysis

This paper describes an empirical study aimed at ranking prequalification criteria on the basis of perceived total cost-benefit to stakeholders. A postal questionnaire was distributed to 100 client and contractor organizations in Australia in 1997. Forty-eight responses were analyzed for scores on 38 categories of contractor information in terms of "value to client" "contractor costs," "client costs," and "value for money." The client and contractor responses for "value to client" and "client costs" of processing were found to be homogeneous. Those for "contractor costs" and "value for money" differed significantly between the clients and the contractors. A simple linear regression analysis was used to model the responses, and an index of cost-benefit was derived for each of the categories. This was found to be superior to all of the nonlinear alternatives examined. The model was also found to have greater intuitive value than the equivalent raw "value for money" responses.
Design of a blood flow system

Blood is a vital but often scarce resource in developing countries. It is crucial that safe blood is made available for transfusions in hospitals and clinics to prevent the spread of Transfusion-Transmitted Infections (TTI) such as HIV, Hepatitis and Syphilis. We present a system designed to promote hemovigilance in developing countries by monitoring the collection and usage patterns of blood, predicting collection and usage for upcoming time periods and finding an allocation assignment for blood distribution that is fair and efficient.
Analysis of Local Quasi-Stationarity Regions in an Urban Macrocell Scenario

A common simplification in the treatment of random linear channels is the wide-sense stationary and uncorrelated scattering (WSSUS) assumption. For wireless channels, this assumption is, however, only fulfilled in an approximative sense inside local time-frequency regions. Since algorithms in wireless digital communications often rely on knowledge of second order statistics of the channel, it is important to know the size of local quasi-stationarity regions. Thus, we determine quasi-stationarity regions in distance for an urban macrocell scenario. We observe that, based on the chosen measure and in our specific scenario, the time-frequency properties are dominant compared to the spatial properties in defining the size of quasi-stationarity regions. Furthermore, we find that in some cases the quasi-stationarity regions strongly depend on the mobile terminal orientation.
A Model for the Failure of Bipolar Silicon Integrated Circuits Subjected to Electrostatic Discharge

The results are presented of a study into the mechanism by which failure occurs in an integrated circuit when it is subjected to a discharge of static electricity. The current that flows through an integrated circuit during a static discharge is shown to be an exponentially decaying current pulse. The peak value and rate of decay of the pulse can be calculated through the use of suitable equivalent circuits. Experimental data was obtained by using a simple test apparatus to simulate the current pulses caused by an electrostatic discharge. The power density and temperature rise at critical locations in the integrated circuit were calculated by using the current expression and the relevant physical and electrical properties of the I. C. Failure was found to occur when the temperature near a junction reached the approximate melting point of silicon. As a consequence of this study, a technique is derived which will permit the prediction of approximate threshold levels of static voltage that will produce failure under various conditions.
Channel guided lasers for plasma accelerators

The recent demonstration of optical guiding of high intensity laser pulses in plasma waveguides [C.G. Durfee III and H.M. Milchberg,  (1993)] has opened the way to new advances in the development of compact laser-driven electron particle accelerators. We review plasma waveguide properties relevant to intense pulse guiding and electron acceleration and show that the shock driven channels described here are well suited for stabilization of a large class of laser-plasma instabilities deleterious to high intensity guiding over long distances.
Estimation and detection of myocardial tags in MR image without user-defined myocardial contours

Magnetic resonance (MR) tagging has been shown to be a useful technique for noninvasively measuring the deformation of an in vivo heart. An important step in analyzing tagged images is the identification of tag lines in each image of a cine sequence. Most existing tag identification algorithms require user defined myocardial contours. Contour identification, however, is time consuming and requires a considerable amount of user intervention. In this paper, a new method for identifying tag lines, which the authors call the ML/MAP method, is presented that does not require user defined myocardial contours. The ML/MAP method is composed of three stages. First, a set of candidate tag line centers is estimated across the entire region-of-interest (ROI) with a snake algorithm based on a maximum-likelihood (ML) estimate of the tag center. Next, a maximum a posteriori (MAP) hypothesis test is used to detect the candidate tag centers that are actually part of a tag line. Finally, a pruning algorithm is used to remove any detected tag line centers that do not meet a spatio-temporal continuity criterion. The ML/MAP method is demonstrated on data from ten in vivo human hearts.
Architecture Based Development with DYNACOMM: Incorporating Dynamic Reconfiguration and Hierarchical Design into CommUnity

Architecture Description Languages (ADLs) were developed to support the abstract level of software structuring that is the subject matter of software architecture. Community is an ADL built on co-ordination principles and a categorical framework to support the composition of specifications of components to form the system's specification. However, an important shortcoming of Community is the lack of integrated support for specifying the system's architectural changes in both the set of components and the connections between them. This paper presents DynaComm, an extension of Community to support hierarchical design and dynamic reconfiguration of component based systems. The architectural design principles supported by the DynaComm language are illustrated through the design of a fault-tolerant, dynamic client-server system. A state anchored semantics of DynaComm is given by reducing a DynaComm design to a Community design, i.e., a configuration of components, cables and superposition morphisms, and then taking the colimit of the Community diagram. The careful use of extension, refinement and superposition morphisms guarantees that this is always possible.
Beam injection and transport experiments with an upgraded injector in the UNM betatron

A study of the injection and transport of a high-power relativistic electron beam (130 A, 300 keV) in the UNM betatron was recently concluded. The electron beam was injected at an angle of 20 degrees with respect to the main axis of the accelerating ring. An electron beam current of 15 A was transported around the entire accelerating ring. The experiments verified that a transverse electric field can be used to bend an externally injected relativistic electron beam onto the main axis of the accelerating ring and that the injected beam can be transported in a periodic solenoidal lens array. The beam injection results were consistent with calculations of the single-particle orbits under the combined influence of a transverse electric field and a strong focusing magnetic field, as were used in the experiment. A large fraction of the electron beam current was lost during injection and transport. This is attributed to a large spread in beam energies that was caused by a nonuniform injector voltage pulse. In order to remedy this difficulty, the Marx generator is being upgraded to 600 kV and a novel crowbar system is being installed.<<ETX>>
Bio-inspired low-complexity clustering in large-scale dense wireless sensor networks

To enhance network scalability and increase network lifetime in large-scale wireless sensor networks (WSNs), clustering has been recognized as an effective solution for hierarchical routing, topology control and data aggregation. Inspired by the collective behavior of flocks and schools, we propose a Bio-inspired self-organizing Low-Complexity Clustering (B-LCC) algorithm for large-scale dense WSNs. The B-LCC algorithm does not require sensor locations, time synchronization nor any priori knowledge of the network. It is completely distributed and can achieve a well-distributed cluster heads. The processing time complexity of the B-LCC algorithm is O(1) per cluster, which outperforms most of the existing clustering algorithms as they have processing time complexity of O(n) per node in the worst case. Additionally, the B-LCC algorithm has a stable performance in topology control and the formed topology is robust to node failure.
3D left ventricular strain by phase unwrapping: A simulated annealing based branch-cut placement method

This paper presents an automated method for measuring 3D left ventricular (LV) strain in each imaged time frame from phase unwrapped harmonic phase (HARP) images derived from tagged cardiac magnetic resonance imaging. In previous work, manuallyplaced branch cuts were used to resolve phase inconsistencies in HARP images before they were unwrapped. This paper presents an automated method for placing branch cuts in short-axis images based on simulated annealing with a new cost function based on temporal phase consistency. This method significantly reduces the amount of user interaction needed to compute 3D strain maps in the entire LV in each imaged time frame. The unwrapped-phase-derived strains were validated on a set of 40 human studies by comparing them to strains estimated by a previously published feature based technique and a previously published unwrapped-phase technique with manual branch cut placement.
Analysis of harmonic mitigation methods for building wiring systems

There is a growing number of available harmonic mitigation methods. Selection of the best suited method for a particular case can be a complicated decision making process. The difficulty normally arises from not knowing how a particular technology and design will perform in a specific nonsinusoidal system. This paper looks at seven harmonic mitigation methods and compares their compensation characteristics as applied to building wiring systems. Both passive and active mitigation methods are considered for harmonics generated by single-phase equipment. The performance is studied through computer simulation with detailed source and associated rectifier load interfaces in the model.
Absolute potential measurements inside microwave digital IC's using a micromachined photoconductive sampling probe

A measurement system for internal node testing of integrated circuits using a micromachined photoconductive sampling probe is described and characterized. Special emphasis is placed upon the system performance, demonstrating how absolute voltage measurements are achieved in a DC-to-MM-wave bandwidth. The feasibility of the setup is illustrated using an InP heterojunction bipolar transistor frequency divider. Detailed waveforms at different circuit nodes and the corresponding propagation delays from within this circuit at operating frequencies up to 10 GHz are presented. The results demonstrate for the first time the use of photoconductive probes for calibration-free, absolute-voltage, DC-coupled potential measurements in high-frequency and high-speed integrated circuits.
Audio–Visual Affective Expression Recognition Through Multistream Fused HMM

Advances in computer processing power and emerging algorithms are allowing new ways of envisioning human-computer interaction. Although the benefit of audio-visual fusion is expected for affect recognition from the psychological and engineering perspectives, most of existing approaches to automatic human affect analysis are unimodal: information processed by computer system is limited to either face images or the speech signals. This paper focuses on the development of a computing algorithm that uses both audio and visual sensors to detect and track a user's affective state to aid computer decision making. Using our multistream fused hidden Markov model (MFHMM), we analyzed coupled audio and visual streams to detect four cognitive states (interest, boredom, frustration and puzzlement) and seven prototypical emotions (neural, happiness, sadness, anger, disgust, fear and surprise). The MFHMM allows the building of an optimal connection among multiple streams according to the maximum entropy principle and the maximum mutual information criterion. Person-independent experimental results from 20 subjects in 660 sequences show that the MFHMM approach outperforms face-only HMM, pitch-only HMM, energy-only HMM, and independent HMM fusion, under clean and varying audio channel noise condition.
Emotion recognition from an ensemble of features

This work details the authors' efforts to push the baseline of expression recognition performance on a realistic database. Both subject-dependent and subject-independent emotion recognition scenarios are addressed in this work. These two happen frequently in real life settings. The approach towards solving this problem involves face detection, followed by key point identification, then feature generation and then finally classification. An ensemble of features comprising of Hierarchial Gaussianization (HG), Scale Invariant Feature Transform (SIFT) and Optic Flow have been incorporated. In the classification stage we used SVMs. The classification task has been divided into person specific and person independent emotion recognition. Both manual labels and automatic algorithms for person verification have been attempted. They both give similar performance.