nils-herrmann/clean_scirepeval huggingface dataset:
Effects of Random Circuit Fabrication Errors on the Mean and Standard Deviation of Small Signal Gain and Phase of a Traveling Wave Tube

Random fabrication errors may have detrimental effects on the performance of traveling wave tubes (TWTs) of all types, especially in the sub-millimeter wavelength regime and beyond. Previous studies calculated the standard deviation of the small signal gain and the output phase of a TWT in the presence of small random, axially varying perturbations in the circuit phase velocity, assuming synchronous interaction and zero AC space charge effects. This paper relaxes the latter assumptions. In addition, we calculate the ensemble-average gain and the ensemble-average phase that result from random axial variations in the circuit phase velocity, using two analytic approaches. One is a perturbative approach including all three modes of the coupled beam-circuit equations. The other treats the evolution of only the dominant (exponentially growing) mode. The analytical results on the expected gain and phase compare favorably with results from numerical integrations of the governing equation in the absence of space charge, but are found to deviate from the numerical integrations with the inclusion of space charge effects. The effects of small pitch errors in a 210 GHz folded waveguide TWT are evaluated in an example.
Dual stress liner enhancement in hybrid orientation technology

Hybrid orientation technology (HOT) has been successfully integrated with a dual stress liner (DSL) process to demonstrate outstanding PFET device characteristics in epitaxially grown [110] bulk silicon. Stress induced by the nitride MOL liners results in mobility enhancement that depends on the designed orientation of the gate, in agreement with theory. Compressive stressed liner films are utilized to increase HOT PFET saturation current to 635 uA/um I/sub DSat/ at 100 nA/um I/sub OFF/ for V/sub DD/=1.0 V at a 45 nm gate length. The AC performance of a HOT ring oscillator shows 14% benefit from [110] silicon and an additional 8% benefit due to the compressive MOL film.
DP-miRNA: An improved prediction of precursor microRNA using deep learning model

MicroRNA (miRNA) are small non-coding RNAs regulating gene expression at the post-transcriptional level. Detecting miRNA in a genome is challenging experimentally and results vary depending on their cellular environment. These limitations inspire the development of knowledge-based prediction method. This paper proposes a deep learning based classification model for predicting precursor miRNA sequence that contains the miRNA sequence. The feature set consists of sequence features, folding measures, stem-loop features and statistical features. We evaluate the performance of the proposed method on human dataset. The deep neural network based classification outperformed support vector machine, neural network, naive Bayes classifiers, k-nearest neighbors, random forests as well as hybrid systems combining SVM and genetic algorithm.
Enhanced 3D geometric-model-based face tracking in low resolution with appearance model

3D geometric-model-based face tracking utilizes 3D geometric face model to extract facial motion information from video. It has the advantages of dealing with oblique views of faces and it is robust to changes in people, expressions and lighting. Although most existing 3D model-based methods work well with high resolution faces (e.g. face regions around 200 /spl times/ 200 pixels), the face image in real environments (e.g. surveillance video) is often in low resolution. In low resolution, the performance of 3D model-based face tracking can be degraded because the underlying low-level image motion estimation is less reliable. In this paper, we present an appearance-based enhancement to 3D geometric-model-based face tracking in low resolution. First, we estimate the motion parameters of the 3D face model. Then we extract the stabilized texture map image of the face model. The appearance variations in the face texture images are caused by the errors in motion estimation or lighting changes. Therefore these appearance variations are used as additional constraints for refining the motion estimations. Experiments show that the proposed enhancement improves the robustness of 3D model-based tracking in low resolution.
A survey on soft Biometrics and their application in person recognition at a distance

Soft Biometrics tried to use demographic informations as gender, ethnicity and soft attributes like eye color, height, color, weight and other visible marks like scars, and tattoos as ancillary information to improve the performance of biometric systems. The soft biometric information is extracted from a human body is ancillary information is easy to identify distinguished at a distance but the recognition task is not fully identified. This paper presents the review on some soft biometrics traits informations and how to detect a person at a distance. This soft biometric information is analyzed based on the scenarios of varying distance between camera and subject. The subjects are close, medium and far. The soft biometric label or trait is able to improve the performance of face recognition based on the sparse representation on real and ideal scenarios by adaptive fusion rules.
A low power (45mW/latch) static 150GHz CML divider

Operation of a static, current mode logic (CML) frequency divider to clock frequencies exceeding 150GHz is reported. The divide-by-8 circuit described here has been realized in a highly scaled 0.4/spl mu/m InP/InGaAs/InP DHBT technology, dissipates only 45mW per latch, and achieves this using purely resistive loads. Thermal limitations in device performance are observed to play a key role, demonstrating the need for aggressive heat management in high speed technologies. On a full thickness wafer in a 27/spl deg/C ambient, the maximum operating frequency of the divider was 143.6GHz; this range extended to 151.2GHz when an air flow at -30/spl deg/C was established across the wafer.
Compact 3-D Envelope ADI-FDTD Algorithm for Simulations of Coherent Radiation Sources

A modified complex-envelope (CE) alternating-direction-implicit (ADI) finite-difference time-domain solver for electromagnetic (EM) fields is presented. Like the conventional ADI scheme, the modified scheme is based on splitting the time step into two halves. In each substep, Maxwell's equations are solved implicitly in one direction and explicitly in the perpendicular direction. The new scheme is a combination of the conventional CE-ADI scheme and the leapfrog ADI scheme that was recently reported. The main features are a more compact form of the tridiagonal equations and greater flexibility in the application of boundary conditions. The boundary conditions on the six faces of the solution box are general and can be specified either as perfect conductor, symmetry boundary conditions, cavity modes, or arbitrary external specification. The new compact CE-ADI scheme is unconditionally stable; thus, the time step can be larger than the one imposed by the Courant-Friedrichs-Lewy (CFL) condition. Fast stable EM simulations of a planar slow-wave structure are demonstrated, with time steps exceeding the CFL limit by two orders of magnitude.
Design of low voltage folded waveguide multiple beam mini-TWTs

Design methodology for low voltage high power multiple beam Traveling Wave Tube (TWT) amplifiers with folded waveguide (FW) slow wave structure (SW) has been developed. Four beam multiple beam (MB) FW TWT operating at 6.2 kV with power per beamlet about 75 W and total power of 300 W has been designed and studied by using NRL large signal codes TESLA-FW and CHRISTINE-FW and NRL GPU based PIC code Neptune. Recent status of experimental demonstration of MB mini TWT in NRL also will be presented.
Comparison Study of Intraoperative Surface Acquisition Methods for Surgical Navigation

Soft-tissue image-guided interventions often require the digitization of organ surfaces for providing correspondence from medical images to the physical patient in the operating room. In this paper, the effect of several inexpensive surface acquisition techniques on target registration error and surface registration error (SRE) for soft tissue is investigated. A systematic approach is provided to compare image-to-physical registrations using three different methods of organ spatial digitization: 1) a tracked laser-range scanner (LRS), 2) a tracked pointer, and 3) a tracked conoscopic holography sensor (called a conoprobe). For each digitization method, surfaces of phantoms and biological tissues were acquired and registered to CT image volume counterparts. A comparison among these alignments demonstrated that registration errors were statistically smaller with the conoprobe than the tracked pointer and LRS ( p <; 0.01). In all acquisitions, the conoprobe outperformed the LRS and tracked pointer: for example, the arithmetic means of the SRE over all data acquisitions with a porcine liver were 1.73 ±0.77 mm, 3.25 ±0.78 mm, and 4.44 ±1.19 mm for the conoprobe, LRS, and tracked pointer, respectively. In a cadaveric kidney specimen, the arithmetic means of the SRE over all trials of the conoprobe and tracked pointer were 1.50 ±0.50 mm and 3.51 ±0.82 mm, respectively. Our results suggest that tissue displacements due to contact force and attempts to maintain contact with tissue, compromise registrations that are dependent on data acquired from a tracked surgical instrument and we provide an alternative method (tracked conoscopic holography) of digitizing surfaces for clinical usage. The tracked conoscopic holography device outperforms LRS acquisitions with respect to registration accuracy.
Clasas: A Key-Store for the Cloud

We propose Clasas (from the Castilian “Claves seguras” for “secure keys”), a key-store for distributed storage such in the Cloud. The security of Clasas derives from breaking keys into K shares and storing the key shares at many different sites. This provides both a probabilistic and a deterministic guarantee against an adversary trying to obtain keys. The probabilistic guarantee is based on a combinatorial explosion, which forces an adversary to subvert a very large portion of the storage sites for even a minute chance of obtaining a key. The deterministic guarantee stems from the use of LH* distributed linear hashing. Our use of the LH* addressing rules insures that no two key shares (belonging to the same key) are ever, even in transit, stored at the same site. Consequentially, an adversary has to subvert at least K sites. In addition, even an insider with extensive administrative privileges over many of the sites used for key storage is prevented from obtaining access to any key. Our key-store uses LH* or its scalable availability derivate, LH*RS to distribute key shares among a varying number of storage sites in a manner transparent to its users. While an adversary faces very high obstacles in obtaining a key, clients or authorized entities acting on their behalf can access keys with a very small number of messages, even if they do not know all sites where key shares are stored. This allows easy sharing of keys, rekeying, and key revocation.
DC-to-mm-wave absolute potential measurements inside digital microwave ICs using a micromachined photoconductive sampling probe

A micromachined photoconductive sampling probe is used to determine detailed wave forms at different circuit nodes and corresponding propagation delays from within an InP HBT frequency divider operating at 2.7 GHz. The results demonstrate for the first time the capability of photoconductive probes for absolute-voltage, DC-coupled potential measurements in integrated circuits.
A Leapfrog Formulation of the 3D ADI-FDTD Algorithm

We introduce a new, alternative form of the 3D alternating direction implicit finite-difference time-domain (ADI- FDTD) algorithm that has a number of attractive properties for electromagnetic simulation. We obtain a leapfrog form of the time advance equations, where the E- and H- fields are staggered at half-integer and integer time steps respectively, that preserves the unconditional stability of the ADI-FDTD method. The resulting equations resemble the explicit leapfrog FDTD method, but the field update equations are modified to include the solution of sets of tridiagonal equations at each step, similar to the original ADI- FDTD scheme, so that the scheme is not constrained by the Courant-Friedrichs-Lewy (CFL) limit. The algorithm is simpler than the ADI-FDTD method but algebraically equivalent, allowing a reduction in computation to achieve the same numerical solution. We discuss the advantages of the formulation over the original FDTD and ADI-FDTD methods, and confirm our results numerically.
A simple noniterative speech excitation algorithm using the LPC residual

This paper provides an analytical derivation of a simple noniterative technique for extracting a multiple impulse excitation model for synthesized speech directly from the LPC residual sequence. While suboptimal with respect to "multipulse" techniques, this method is very applicable for speech enhancement where processor capability is limited. The results suggest an additional "orthogonality" requirement between the excitation sequence and the resulting prediction error, which aids in the intuitive understanding of the method.
A three-dimensional multifrequency large signal model for helix traveling wave tubes

A three-dimensional (3D) multifrequency large signal model of the beam wave interaction in a helix TWT is described. The beam is divided into a set of discrete rays, or "beamlets", instead of the disks or rings used in one-dimensional (1-D) or two-dimensional (2-D) models. The RF fields supported by the helix are represented by a tape helix model that uses a modal expansion including the full (Bessel function) radial dependence of the fields; both forward and backward synchronous space harmonics are included in the model. RF space charge fields are obtained from solutions of the Helmholtz equations for the RF electric and RF magnetic fields, using the beam current and charge densities as sources. The dc space charge electric field is similarly obtained from a solution of Poisson's equation. This model has been implemented in a code called CHRISTINE 3D, a generalization of the one dimensional CHRISTINE code. The full three dimensional treatment permits the accurate computation of large signal gain and efficiency, taking into account the self-consistent variation of beam radius along the interaction space. The code also computes helix interception current and transverse beam distributions at the entrance to the collector-important design data that are unavailable from a 1D model. Results from the CHRISTINE 3D code are shown to compare very favorably with measurements of output power, efficiency, and interception current vs. drive power. Its predictions for spent beam distributions also compare very well with measurements. Run times for the code are problem dependent, but for a single case of interest are typically 1 to 5 min on a 450 MHz PC, orders of magnitude shorter than that required for a comparable 3D particle-in-cell simulation.
Effective and efficient sports highlights extraction using the minimum description length criterion in selecting GMM structures [audio classification]

In fitting the training data with Gaussian mixture models (GMMs) of appropriate structures using the MDL (minimum description length) criterion, we are able to improve audio classification accuracy with a large margin. With the MDL-GMMs, we are also able to greatly improve the accuracy in extracting sports highlights. Since we have focused on audio domain processing, it enables us to extract highlights very quickly. We have demonstrated the importance of a better understanding of model structures in such a pattern recognition task.
Cluster head placement in Wireless Sensor Network for reliable connectivity and lifetime extension

A novel method of locating Cluster Heads in a Clustered Wireless Sensor Network is proposed to achieve longer lifetime while maintaining reliable connectivity. The network lifetime is increased by reducing the required minimum transmission range of the sensors. The reduction in the transmission range is achieved by inserting high powered Cluster Heads at intermediate strategic locations. The reduced transmission range of nodes decreases the operating power levels of the individual sensors. Consequently, the overall lifetime of the Wireless Sensor Network is extended. Forming appropriate clusters and then calculating the location of the Cluster Head within each cluster is the main objective of this paper. Maintaining a higher degree of network connectivity and operating the sensors at lowered transmission range are conflicting objectives by their very nature. When the transmission range of sensors is reduced, the network connectivity may be lost depending on the network topology and the geographical locations of the sensor. To overcome this problem, we insert Cluster Heads at calculated optimal locations to provide good connectivity while lowering the transmission range of Sensor. To achieve this goal, we introduce smallest_circle function which uses constrained nonlinear programming function fmincon of Matlab. We also propose a new iterative clustering algorithm that solves the absolute minimum p-center minimax facility location problem.
Accurate Representation of Attenuation in Helix TWT Simulation Codes

We report on the results of a study that compares an ad hoc model of circuit attenuation used in helix traveling-wave tube (TWT) simulation codes with the exact small-signal theory of a beam interacting with a slow wave supported by a sheath helix in the presence of loss in order to ascertain whether attenuation is treated with sufficient accuracy by the model used in those codes. This study was motivated in part by the fact that losses in both dielectrics and metals generally increase with increasing operating frequency, making the accuracy of the model a potential concern for millimeter-wave helix TWT design. Our basic conclusion is that the ad hoc model is sufficiently accurate for attenuation rates up to a few decibels per pitch in cases that we have studied. For much larger attenuation rates, as may occur in a sever region, accuracy can be improved by taking into account the (quadratic) dependence of the cold circuit phase velocity on the attenuation rate.
Estimating 3D vehicle motion in an outdoor scene from monocular and stereo image sequences

The main goal of this research is to test how well existing feature extraction, matching and motion estimation algorithms (with appropriate modification) work on outdoor scenes. For this purpose, a careful calibrated image sequence data base has been created. The data used for the results reported in the paper consists of a sequence of 24 stereo images of an outdoor scene containing a moving truck with stationary background. Two motion estimation methods using feature correspondences were applied in the data: point correspondences over two stereo image pairs and line correspondences over three monocular images. In spite of the large values of the range to baseline ration (10:1) and the range to focal length ration (1000:1), the estimated rotation parameters are reasonably accurate (10-20% errors) in both methods. Although the translation estimates in the monocular method are large, the translation errors in the stereo method are around 1 meter, and are mainly due to image sampling.<<ETX>>
A simulation study of beam loading on a cavity

Beam loading exerts a strong influence on the operation of high-power and medium-power microwave sources. This paper reports a simulation study of beam loading on a cavity using the two-dimensional particle-in-cell code, MAGIC. We vary the beam voltage, the beam current, the degree of current modulation on the dc beam before the beam enters the cavity, and the degree of charge neutralization on the beam. We deduce the beam-loaded quality factor Q and the beam-loaded resonant frequency from a Lorentzian fit of the numerical data on the gap voltage response as a function of the driving frequency. The MAGIC simulations have revealed several unanticipated results. The beam loading is observed to be a function of perveance. Constant perveance beams, of varying voltage and current, exercise about the same degree of beam loading on the model klystron cavity (except, of course, for the cases with very small beam current). The inclusion of an ac component on the dc beam current has no effect on the degree of beam loading; neither does the neutralization of the electron beam. Many of these simulation results cannot be explained by existing theories that ignore ac space charge effects.
Computer simulations of gyrotrons with coaxial cavities

Computer simulations of high power coaxial gyrotrons have been done by using modified code MAGY. 1.5 MW, 165 GHz FZK (Germany) and industrial 2 MW/CW, 170 GHz CRPP/EPFL, FZK, TEKES and males Electron Devices gyrotrons have been used as basic configurations for modelling. Results of simulations, their comparison with experiments and discussion on advantages and limitations of gyrotron computer simulations will be presented.
Design of a fresh meat packing robot for working in washdown environment

The benefits of robotics are evident in many industries. However, the food processing industry has not been able to realize this benefit due to the limitations imposed by the operating environment. The demanding environment in the handling of fresh meat products typically includes a daily wash with high pressure as well as highly corrosive cleaning agents. This paper described the development of a robot specifically built for handling fresh meat products in such environment. The selection of materials for washdown working conditions, as well as the unique coaxial shaft design, was specified. Based on the specific motion, the system kinematics and dynamics were formulated. The simulation results provided the optimal motions to minimize the centrifugal force on the meat (grasper). The dynamic model also yielded the speed and torque relationship, which helped to provide the criteria for motor selection and the verification of the applicability of the selected motors. A functional prototype has been built and is under evaluation.
Accurate and efficient reconstruction of 3D faces from stereo images

In this paper, we propose a novel algorithm for reconstructing the 3D shape and texture of human faces from two stereo images, which are captured from calibrated cameras. Our approach works in a sparse to dense manner: we first build a coarse shape estimation based on 3D keypoints, and then use a linear morphable model to efficiently match the detail shape and texture. Compared with the previous works, our algorithm can reconstruct the 3D face shape in a speed comparable with that of the fastest algorithm available, but gives a higher accuracy. It can also recover the texture with more complete, realistic looking. Our results show that the new algorithm possesses significant characteristics of a 3D face model reconstruction system, and is especially useful for face recognition and animation applications in practice.
An advanced controlled-flooding routing with group organization for Delay Tolerant Networks using A-SMART

Delay Tolerant Network (DTN) is a network in which end-to-end connectivity may not be guaranteed because of the frequent and long duration partitions. SMART routing, which is a selective controlled-flooding scheme, utilizes travel companions of the destinations and improves the delivery opportunities, but its flooding overhead can be further controlled. In this paper, we propose A-SMART routing which combines the companion features and ANYCAST forwarding-based scheme, it is aimed at further flooding control. Our study shows that A-SMART has a better performance than the selective controlled-flooding in terms of message delivery ratio and overhead ratio. In A-SMART routing, the reliability increases while the number of messages propagated decreases.