nils-herrmann/clean_scirepeval huggingface dataset:
Active contours in optical flow fields for image sequence segmentation

Using variational calculus we develop an active contour model to segment an object across a number of image frames in the presence of an optical flow field. We define an energy functional that is locally minimized when the object is tracked across the entire image stack. Unlike classical snakes, image forces and regularization terms are integrated over the full set of images in the proposed model. This results in a new formulation of active contours. The method is demonstrated by segmenting the ascending aorta in a phase-contrast cine MRI dataset. Techniques to compute the required optical flow field and a “one-click” contour initialization step are suggested for this particular modality.
3D head pose computation from 2D images: templates versus features

In this paper we examine the problem of determining 3-D human head pose from a sequence of 2-D gray scale images. Computation of head pose is vital in many areas of human head modeling and applications include model-based video compression, face recognition and 3D head tracking. A significant amount of research has been done in the general area of 3D object alignment for recognition and modeling purposes, with much of the work concentrating on applying techniques to simple polyhedral objects such as cubes or polyhedrons. We take these techniques a step further and apply them to grey scale images of human heads using a set of distinguishing facial features as well as 2D template regions to compute the pose relative to a given 3D model. In the feature point approach, we use a small subset of features and optimize their selection by minimizing the error in mapping the remaining points with the computed pose. In the template method we minimize the difference in energy between the input facial region and the template database. We obtain results for a wide range of head orientations and scales and the methods proved to be quite accurate.
Design, development and commissioning of a supervisory control and data acquisition (SCADA) laboratory for research & training

This paper reports a state-of-the-art SCADA laboratory facility for power systems at Jamia Millia Islamia, New Delhi. It has been designed to function as a research and training center for utilities, faculty members and students. The paper covers the design, commissioning and functioning of the SCADA/EMS laboratory facility, based on distributed-processing technology. The SCADA laboratory provides hands on experience to students and practicing engineers and gives them an insight into the contemporary SCADA systems. This lab is the first of its kind to be functional in India.
Development of high average power W-band gyro-amplifiers for radar applications

There is currently a need for high-power, W-band amplifiers for a number of existing and planned millimeter-wave radar applications. In response to this need, a 10 kW average power, W-band (94 GHz) gyroklystron amplifier was designed and tested in a collaborative effort between the Naval Research Laboratory (NRL), Litton Electron Devices, Communications and Power Industries (CPI), and the University of Maryland.
An accurate, large signal, high frequency model for GaAs HBTs

An accurate compact circuit simulation model has been developed for the large-signal, high-frequency behavior of GaAs single heterojunction bipolar transistors (HBTs). A unified, physically-based, quasistatic collector charge function models both base-collector capacitance and collector transit time. It naturally handles collector space-charge effects, "full-depletion" of the collector n region, and the dependence of the high-field electron velocity in GaAs on electric field and temperature. An improved charge expression accounts for the Kirk effect. This formulation has produced excellent model fits to measurements of AlGaAs-GaAs HBTs.
An Evolutionary Approach to Synthetic Biology: Zen and the Art of Creating Life

Our concepts of biology, evolution, and complexity are constrained by having observed only a single instance of life, life on earth. A truly comparative biology is needed to extend these concepts. Because we cannot observe life on other planets, we are left with the alternative of creating Artificial Life forms on earth. I will discuss the approach of inoculating evolution by natural selection into the medium of the digital computer. This is not a physical/chemical medium; it is a logical/informational medium. Thus, these new instances of evolution are not subject to the same physical laws as organic evolution (e.g., the laws of thermodynamics) and exist in what amounts to another universe, governed by the physical laws of the logic of the computer. This exercise gives us a broader perspective on what evolution is and what it does. An evolutionary approach to synthetic biology consists of inoculating the process of evolution by natural selection into an artificial medium. Evolution is then allowed to find the natural forms of living organisms in the artificial medium. These are not models of life, but independent instances of life. This essay is intended to communicate a way of thinking about synthetic biology that leads to a particular approach: to understand and respect the natural form of the artificial medium, to facilitate the process of evolution in generating forms that are adapted to the medium, and to let evolution find forms and processes that naturally exploit the possibilities inherent in the medium. Examples are cited of synthetic biology embedded in the computational medium, where in addition to being an exercise in experimental comparative evolutionary biology, it is also a possible means of harnessing the evolutionary process for the production of complex computer software.
Blind digital watermarking for images and videos and performance analysis

Digital watermarking is a promising technique to help protect data security and intellectual property rights. A blind digital image/video watermarking technique is proposed. A multiresolution pyramid transform is applied to a host image. A tight upper bound for the modulation of watermark signals is derived to control the fidelity loss. The robustness is optimized under the fidelity constraints. An optimum decision rule for the detection is derived using the statistical model of the generalized Gaussian distribution. Asymptotic performance analysis is provided. The simulations demonstrate that near perfect invisibility, very strong robustness, and optimum detection are obtained. The watermarking system can be applied to copyright notification, enforcement, and fingerprinting.
Cross regulation in a two-output DC-to-DC converter with application to testing of energy-storage transformers

Cross regulation is a technique for providing multiple regulated output voltages from an energystorage dc-to-dc converter where only one of the outputs is actually sensed by the controller and regulated to the desired value. The regulation of the remaining output voltages depends on the magnetic coupling between the multiple secondary windings of the energy-storage transformer. This paper extends the analysis of [l] by examining the cross regulation performance of a two-output voltage step-up/current step-up dc-to-dc converter operating in the continuous mmf mode under constant-frequency control. The analysis is shown to be a useful tool for generating test specifications for screening energy-storage transformers to guarantee that the leakage flux associated with the transformers does not prevent the converter from providing adequate cross regulation.
Combined tag tracking and myocardium motion reconstruction from planar tagged MR image data without user-defined myocardial contours

We present a method for combined tag tracking and myocardium motion reconstruction from planar tagged MR image data that does not require user-defined myocardial contours. The method uses a cylindrical B-spline deformable model which more closely matches the shape of left ventricle than a Cartesian B-spline model. Experimental results on eight human imaging studies indicate that our method can track tag lines more accurately and faster than a previously proposed technique, which used manually determined myocardial contours. Also, circumferential strains computed by our method compare well with strains computed from expert edited tag lines using other deformation models.
Effects of Real-World Versus Virtual Environments on Joint Excursions in Full-Body Reaching Tasks

Starting from an upright standing posture and reaching for a target that requires some forward bending of the trunk can involve many different configurations of the trunk and limb segments. We sought to determine if configurations of the limb and trunk segments during our standardized full-body reaching tasks were influenced by the visual environment. This paper examined movement patterns of healthy participants (\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} }{}$n=17$ \end{document}, eight female and nine male) performing full body reaching tasks to: 1) real-world targets; 2) virtual targets presented on a 3-D television; and 3) virtual targets presented using a head-mounted display. For reaches performed in the virtual world, the avatar was presented from a third-person perspective for the 3-D television and from a first-person perspective for the head-mounted display. Reaches to virtual targets resulted in significantly greater excursions of the ankle, knee, hip, spine, and shoulder compared with reaches made to real-world targets. This resulted in significant differences in the forward and downward displacements of the whole-body center of mass between the visual environments. Visual environment clearly influences how subjects perform full-body reaching tasks to static targets. Because a primary goal of virtual reality within rehabilitation is often to restore movement following orthopedic or neurologic injury, it is important to understand how visual environment will affect motor behavior. The present findings suggest that the existing game systems that track and present avatars from a third-person perspective elicit significantly different motor behavior when compared with the same tasks being presented from a first-person perspective.
A testbed for a unified teleoperated-autonomous dual-arm robotic system

A description is given of a complete robot control facility built at the CIT Jet Propulsion Laboratory as part of a NASA telerobotic program to develop a state-of-the-art robot control environment for laboratory-based spacelike experiments. This system has the following features: separation of the computing facilities into local and remote sites, autonomous motion generation in joint or Cartesian coordinates, dual-arm force reflecting teleoperation with voice interaction between the operator and the robots, shared control between the autonomously generated motions and operator controlled teleoperation, and dual-arm coordinated trajectory generation. The system has been used to carry out realistic experiments such as the exchange of an orbital replacement unit, bolt turning, and door opening, using a mixture of autonomous actions and teleoperation, with either a single arm or two cooperating arms.<<ETX>>
An SIMD Multiprocessor Ring Architecture for the LMS Adaptive Algorithm

A new architecture for a single instruction stream, multiple data stream (SIMD) implementation of the LMS adaptive algorithm is investigated. This is denoted as a ring architecture, due to its physical configuration, and it effectively solves the latency problem often associated with prediction error feedback in adaptive filters. The multiprocessor ring efficiently updates the filter input vector by operating as a pipeline structure, while behaving as a parallel structure in computing the filter output and applying the weight adaptation algorithm. Last, individual processor timing and capacity considerations are examined.
An introduction to computer algorithms designed to facilitate I/sub DDT/ current testing of CMOS circuits

This work presents an overview of a new computer algorithm and a computer aided design (CAD) tool. Both of these prove to be useful for dynamic power supply current test methods. In the growing field of iDDT testing many analysis tools that have existed for decades can be used effectively to provide various its levels of results. However, new fields of study often require new tools. This work presents an introduction to the "Toggle" algorithm and the "Mapper" CAD tool. These tools can be used to advance the study and practice of iDDT testing as well as other testing methods
Comparison of standards limiting harmonic distortion in power systems

Harmonic distortion in power systems is growing due to the popularity of switch-mode power electronic equipment. This electronic equipment has recognized advantages, including reducing weight and improving control and efficiency in power converters and supplies. A disadvantage of switch-mode power electronic equipment is that the low-cost utility interface design approach may burden the power system with harmonic loading. Methods to reduce this distortion exist but economic incentives do not. Standards are emerging as the most effective means to influence equipment design and control distortion in power systems. This work compares the major European and American harmonic limiting standards.<<ETX>>
Annotating collections of photos using hierarchical event and scene models

Most image annotation systems consider a single photo at a time and label photos individually. In this work, we focus on collections of personal photos and explore the associated GPS and time information for semantic annotation. First, we employ a constrained clustering method to partition a photo collection into event-based sub-collections, considering that the GPS records may be partly missing (a practical issue). We then use conditional random field (CRF) models to exploit the correlation between photos based on (1) time-location constraints and (2) the relationship between collection-level annotation (i.e., events) and image-level annotation (i.e., scenes). With the introduction of such a multi-level annotation hierarchy, our system addresses the problem of annotating consumer photo collections that requires a more hierarchical description of the customerspsila activities than do the simpler image annotation tasks. The efficacy of the proposed system is validated using a geotagged customer photo collection database, which consists of over 100 folders and is labeled for 12 events and 12 scenes.
Complex permeability variations of iron excess CoNiZn ferrites with annealing temperature

Induced anisotropy due to Co2+ions in excess iron ferrites is known to increase the magnetic Q, and the technologically important μQ product, by increasing the restoring force on domain walls. This anisotropy can be induced by slow cooling from below the Curie temperature. This paper studies the further increases in the magnetic Q that occur for slow cooling from above the Curie temperature. We show from measurements of the complex permeability spectrum between 1 and 1000 MHz that such improvements are due to a decrease in domain wall damping. Measurements of d.c. resistivity, an Auger spectroscopy analysis of grain boundary impurities and a thermogravimetric analysis indicate that oxidation of Fe2+ions in both grain boundaries and interiors is the origin of the decrease in the domain wall damping.
A unified structure-based framework for indexing and gisting of meetings

A variety of media involve the spoken interaction of people. For this media to be useful, indexing and browsing facilities must be provided to the user. We present a unified framework for indexing and gisting spoken interactions of people. We use speaker identification, prosody analysis and word spotting as preprocessing steps to find the structure of the meeting. The structure is modeled using a stochastic approach based on the hidden Markov model. The result of the analysis is an outline or table of content, as well as a rich set of visual queues for navigating the media. In addition to the automatic analysis, we provide the user with tools for browsing the meeting, as well as tools for directing the analysis and editing the results. We present early results using the proposed framework.
Cross-dataset action detection

In recent years, many research works have been carried out to recognize human actions from video clips. To learn an effective action classifier, most of the previous approaches rely on enough training labels. When being required to recognize the action in a different dataset, these approaches have to re-train the model using new labels. However, labeling video sequences is a very tedious and time-consuming task, especially when detailed spatial locations and time durations are required. In this paper, we propose an adaptive action detection approach which reduces the requirement of training labels and is able to handle the task of cross-dataset action detection with few or no extra training labels. Our approach combines model adaptation and action detection into a Maximum a Posterior (MAP) estimation framework, which explores the spatial-temporal coherence of actions and makes good use of the prior information which can be obtained without supervision. Our approach obtains state-of-the-art results on KTH action dataset using only 50% of the training labels in tradition approaches. Furthermore, we show that our approach is effective for the cross-dataset detection which adapts the model trained on KTH to two other challenging datasets1.
A wideband 60 GHz differential stripline-to-waveguide transition for antenna measurements in low-temperature co-fired ceramics technology

Modern communication systems require an ever increasing bandwidth for high data-rate communication systems. The internationally available 60 GHz industrial, scientific and medical band permits unlicensed communication links for wireless local and personal area networks. Leveraging the advanced integration and miniaturization of end-user devices enabled by low-temperature co-fire ceramics technology (LTCC), 60 GHz antennas can be directly integrated with frontend MMICs into compact systems. We have designed, fabricated, and tested an LTCC stripline-to-waveguide transition intended for verification of planar antennas and other active or passive components at millimeter-wave frequencies.
Design of radio frequency energy harvesting system for an unmanned airplane

Energy harvesting is a promising technique that can be used to drive various sorts of passively powered devices . Viable energy sources include wind, sunlight, thermal energy, radio waves, mechanical vibration and so on. As an energy source existing ubiquitously in our environment, radio frequency (RF) energy harvesting has the potential to be widely applied. In this work, an RF energy harvesting system is described for the purpose of driving an unmanned airplane. Eventually, the airplane will be capable of remote recharge and become a self-powered system.
Analysis of constraint handling methods for the gravitational search algorithm

The gravitational search algorithm (GSA) is a recent addition to the family of global optimization algorithms based on phenomena found in nature, specifically the gravitational attractive force between two bodies of mass. However, like almost all global search algorithms of this type, GSA has no direct method of handling a constrained optimization problem. There has been much attention to constraint handling using other agent based systems, though the mechanics of GSA make the application of many of these difficult. This paper has therefore analysed constraint handling methods for use with GSA and compared the performance of simple to implement methods (penalties and feasible directions) with a novel separation-sub-swarm (3S) approach, and found that feasible direction methods ideally need at least one initially feasible particle, and that the novel 3S approach is highly effective for solving constrained optimization problems using GSA outperforming the other approaches tested.
Distributed Video Coding using Compressive Sampling

In this paper, we propose a new Distributed Video Coding (DVC) algorithm based on Compressive Sampling principles. Our encoding algorithm transmits a set of measurements of every frame block. Using these measurements, the decoder finds an approximation of each block as a linear combination of a small number of blocks in previously transmitted frames. Thanks to the simplicity of the encoding, our algorithm can be useful in those video applications that require very low complex encoders. However, our algorithm is less efficient than another state-of-the-art DVC technique.
Effect of DC Space Charge Fields in the Interaction Gaps of Coupled Cavity TWTs

During the passage of an electron beam through an interaction gap in a cylindrical beam tunnel, the beam experiences first a decelerating and then a re-accelerating force due to the axial self-electric field produced by the DC beam charge density in the vicinity of the gap. In the absence of RF fields, the beam returns to the same velocity at the exit of the gap that it had at the entrance. The net effect, however, is a slight reduction in the average axial velocity of the beam, compared to what the velocity of the beam would have been in the absence of the gap. This (current dependent) velocity reduction changes the degree of synchronism between the beam velocity and the phase velocity of the slow wave supported by the coupled cavity circuit. One practical effect is a current dependent shift in the location of the peak in the small signal gain vs. voltage curve to higher voltage. In this paper we will present an analysis of this effect and discuss several examples. The DC potential and electric field due to a cylindrical beam propagating in a perfectly conducting cylindrical pipe with a gap has been computed analytically from Poisson's equation for the two different idealized gap geometries. A detailed comparison of results from the analytic expressions for the electric field with numerical results from the MICHELLE gun/collector code shows very good agreement between the two. The analytical expressions for the field have been implemented in the CHRISTINE-CC large signal coupled cavity simulation code. The analytical results for the DC field and sample small and large signal numerical results from the CHRISTINE-CC code will be presented.
Design of a Tool Integrating Force Sensing With Automated Insertion in Cochlear Implantation

The quality of hearing restored to a deaf patient by a cochlear implant in hearing preservation cochlear implant surgery (and possibly also in routine cochlear implant surgery) is believed to depend on preserving delicate cochlear membranes while accurately inserting an electrode array deep into the spiral cochlea. Membrane rupture forces, and possibly, other indicators of suboptimal placement, are below the threshold detectable by human hands, motivating a force sensing insertion tool. Furthermore, recent studies have shown significant variability in manual insertion forces and velocities that may explain some instances of imperfect placement. Toward addressing this, an automated insertion tool was recently developed by Hussong et al. By following the same insertion tool concept, in this paper, we present mechanical enhancements that improve the surgeon's interface with the device and make it smaller and lighter. We also present electomechanical design of new components enabling integrated force sensing. The tool is designed to be sufficiently compact and light that it can be mounted to a microstereotactic frame for accurate image-guided preinsertion positioning. The new integrated force sensing system is capable of resolving forces as small as 0.005 N, and we provide experimental illustration of using forces to detect errors in electrode insertion.