nils-herrmann/clean_scirepeval huggingface dataset:
Optimization design of the contact and shield in vacuum interrupter based on the genetic algorithm

In this paper, based on the electric field analysis, the optimizations for the end of floating shield and the back of contacts are realized using the combined method, charge simulation method (CSM) and genetic algorithm (GA). The floating shield potential has been successfully determined by the CSM. With the aid of solving the inverse problem and the computer simulation, the improved external dimensions of the floating shield and the contacts are presented. The theoretical basis for the insulation design is provided. Compared with the experiment on 35 kV vacuum interrupter, the computer results are reasonable.
Optimization of electrode contour based on novel hybrid algorithm

The genetic algorithm (GA) and tabu search (TS) algorithm are well known. A novel optimization method for continuous variables of global optimization, a hybrid algorithm, is proposed, that is, the TS is embedded into the GA. It combines the advantages of both the GA and IS algorithm, possessing quicker convergence and obtaining global optimum in the highest probability. The feasibility and validity of the proposed hybrid algorithm are verified by solving the typical mathematical function, and the practicability is proved by optimizing the electrode contour. (2 pages)
Tight upper bounds for cell loss probabilities in ATM multiplexers and required bandwidth estimation

Estimating the cell loss probability in an ATM multiplexer is a key issue in network management and traffic control such as call admission control and bandwidth allocation. In this paper, we derive a new approximation to estimate the total and individual cell loss probabilities in an ATM multiplexer fed by a superposition of heterogeneous on-off sources with exponentially distributed on and off periods. Based on this approximation, a simple and accurate method is proposed to estimate the aggregate required bandwidth by a given mix of traffic to guarantee a given cell loss probability.
Gradient Feature Selection for Online Boosting

Boosting has been widely applied in computer vision, especially after Viola and Jones's seminal work. The marriage of rectangular features and integral-image- enabled fast computation makes boosting attractive for many vision applications. However, this popular way of applying boosting normally employs an exhaustive feature selection scheme from a very large hypothesis pool, which results in a less-efficient learning process. Furthermore, this poses additional constraint on applying boosting in an onine fashion, where feature re-selection is often necessary because of varying data characteristic, but yet impractical due to the huge hypothesis pool. This paper proposes a gradient-based feature selection approach. Assuming a generally trained feature set and labeled samples are given, our approach iteratively updates each feature using the gradient descent, by minimizing the weighted least square error between the estimated feature response and the true label. In addition, we integrate the gradient-based feature selection with an online boosting framework. This new online boosting algorithm not only provides an efficient way of updating the discriminative feature set, but also presents a unified objective for both feature selection and weak classifier updating. Experiments on the person detection and tracking applications demonstrate the effectiveness of our proposal.
The Cao Method for Determining the Minimum Embedding Dimension of Sea Clutter

To verify whether sea clutter has chaotic character or not, the minimum embedding dimension and time delay in phase space reconstruction are needed. This paper discusses two defects of false nearest neighbors (FNN) for calculating embedding dimension: noise sensitivity and effect of subjective parameter. It was confirmed that Cao method could overcome these limitations and settle on a suitable embedding dimension of time series and distinguish deterministic signals and stochastic signals clearly. It is concluded that sea clutter is composed of stochastic component and determined component together
A more efficient mechanism of FDTD method based on message passing interface

Based on the message passing interface (MPI) implement of parallel FDTD, this paper puts forward a more efficient mechanism, which decreases the time of communication and synchronization so as to enhance the efficiency of parallel FDTD. The efficient mechanism mainly consists of overlapping model and logic layer model. In addition, this paper also analyzes the performance gain in various network environments. Meanwhile the mechanism reduces the interdependence between processes so that expanding parallel FDTD into grid computing (Foster et al., 2003) environment is feasible.
High-Speed Bioassembly of Cellular Microstructures With Force Characterization for Repeating Single-Step Contact Manipulation

In vitro tissues are significant biological substitute for drug test, cell morphogenesis exploration and organ transplantation. In this letter, a novel microrobotic bioassembly method is proposed to engineer 3-D cellular structure, which can be utilized to culture in vitro tissue with microstructural features. A microrobotic system is set up under optical microscope with 30 nm positioning resolution. To assemble cellular micromodules, the system repeats a programmed single-step contact motion with one manipulator, which effectively avoids human intervention and frequent alignment of micromanipulators. The contact force is analyzed and the system is modeled to be a cantilever handing beam for dynamic force characterization. Through the characterization, we figure out the key parameter as the stiffness of micromanipulator at contact point, which influences assembly success rate. After the calibration of stiffness, the high-speed assembly of cellular structure is performed with an assembly speed of 20 micromodules/min. Finally, the 3-D cellular structure incorporating vascular-like microtube is engineered for the fabrication of in vitro micro tissues.
State estimation of infrared target using particle filter

A filtering algorithm for estimating the position of a moving target using information collected by multiple imaging sensors is presented. Based on camera model and theory of particle filter, state transition model and observation model are set up. Weights threshold is proposed to solve the real-time tracking problem in occlusion issue. The experimental positioning system has been set up to test the algorithm, and the results show that the algorithm is effective in tracking moving target. The estimation error in position of the proposed algorithm is within 0.0082m in tracking stationary target and 0.01m for moving target. State estimation based on PF keeps stable in occlusion condition and is much better than Kalman filter (KF) and extended Kalman filter (EKF) which have large volatility. The experiments results show that the algorithm has good precision and anti-interference performance.
Detection method of low voltage series DC arc based on the pattern matching algorithm

The paper presents a method of the series arc fault for DC systems. The aim of the study is to find some current characteristics, which can be significant for the purpose of arc detection. The validity of the proposed method is testified by analyzing the arc fault current signal. The low voltage series DC arc study is carried out on the currents waveforms acquired during some tests on electric appliances. A Fast Fourier Transformation(FFT) is applied to decompose the monitored current signals into a series of detailed arcing features. Dynamic time warping (DTW) is used to measure the input and the known arc model. The pattern matching algorithm is then used to detect and classify the arc fault. As a result, the method is effective in detecting and classifying the arc fault, and easy to be realized in the practical cases.
Fog Removal from Video Sequences Using Contrast Limited Adaptive Histogram Equalization

The video sequences degraded by fog suffer from poor visibility. In this paper, we present a Contrast Limited Adaptive Histogram Equalization(CLAHE)-based method to remove fog. CLAHE establishes a maximum value to clip the histogram and redistributes the clipped pixels equally to each gray level. It can limit the noise while enhancing the contrast. First, the background image is extracted from the video sequence. And then the moving pixels are estimated and bounded into foreground images. Second, the foreground and background images are defogged respectively by CLAHE. Third, the foreground and background images are fused into the new frames. Finally, the defogged video sequence is obtained. We experiment with a video sequence degraded by fog to evaluate the effectiveness of our method. And the histogram statistics are applied in comparison with traditional method. The results show that our method is more effective than traditional method. In addition, our method can fill the requirement of real-time.
Insulation analyses for vacuum interrupter using multigrid and finite element method

High precision domain discretization and field solution efficiency is the barrier of electric field numerical simulation for multi-dielectrics and complex structure by finite element method (FEM). In this paper, by applying the adaptive control strategy in the transformation between coarse grid and fine grid, an adaptive multigrid-finite element method (AMG-FEM) based on non-structure grid is presented. For simulating the multi-dielectrics and complex electric filed, domain decomposition method (DDM) is employed. And the feasibility and validity of the proposed AMG-FEM/DDM with higher precision and efficiency is verified by calculating the electric field of a vacuum interrupter (VI). And the electric field distributions of the VI with different opening strokes have been figured out dynamically.
Padé approximation based method for computation of eigenvalues for time delay power system

Transcendental terms appear in the characteristic equation of a power system and results in an infinite number of eigenvalues, when time delays in the feedback signals of power system wide-area damping controllers are considered. This makes it very difficult to obtain system eigenvalues via direct solution of the equation. In this paper, a method for computing a reduced set of eigenvalues of a time delay power system is proposed by using Padé rational polynomials to approximate the delays. The Padé polynomials are firstly transformed into their equivalent state space representations. By interconnecting the models of the open-loop power system, wide-area damping controllers and the state space representations of time delays, the linearized model for the closed-loop power system is then established and a reduced set of eignevalues of the system can be computed. The method has been tested on the New England 10-machine 39-bus test systems and compared with the eigenvalue computation method in the software package DDE-BIFTOOL. It shows that the proposed Padé approximation-based method can accurately obtain nearly all of the eigenvalues relating to system dynamic devices. The number of eigenvalues relating to time delays that can be correctly computed and their accuracy strongly relates to the orders of the Padé rational polynomials.
Study on chaotic dynamic arc behavior in SF6 circuit breaker

Based on the arc mathematical model for the SF6 circuit breaker (CB), the equations describing the arc chaotic behavior were deduced by considering the velocity and temperature effect in the model as the chaotic characteristics and expending in 2D form using the convergence of Fourier series. The time series, and Lyapunov exponents diagram reflecting the chaotic behavior of arc were obtained based on the numerical analyses, which proved that the arc behavior exist chaos during the arc quenching. In order to reflect the interactions of the coupling of the electric field, magnetic field and gas flow field and confirm the factors affecting the arc chaotic behavior, third-order nonlinear differential equations with constant coefficient for arc in SF6 CB has been obtained by introducing Maxwell and current density equations in the arc mathematical model and linearizing a set of nonlinear differential equation for the arc model according to the stability theory. The results show that the shock wave is one of the origin of the arc instability. By adjusting the parameters for SF6 CB closely related to the temperature, the system has significant chaotic behavior, which indicates that the system stability can be effectively controlled according to the temperature.
Design of a 94 GHz compact corrugated horn with ultra-low sidelobe

In this paper, a compact tanh/linear dual profile corrugated horn in millimeter-wave band is proposed. To reduce the size of the horn and achieve a low sidelobe level, the parameters of the corrugation profile have been optimized by the commercial software CHAMP. At the central frequency of 94 GHz, the simulation results show that the proposed horn can achieve very low sidelobe around -50 dB with a cross-polarization level about -64 dB.
A reserach on complex network model of field visibility of electric field in SF6 circuit breaker

Based on complex network theory, this paper puts forward a network construction method based on the field visibility of visibility principle, analyzes the inherent properties of electric field, and excavates the important information contained in electric field. By constructing the complex network model through uniform electric field of plate electrodes and slightly non-uniform electric field of high-pressure SF6 gas circuit breaker (HV SF6 GCBs), this paper introduces the complex network theories into field distribution in electric field for study. Besides, it finds that the uniform electric field network of plate electrodes presents regular network characteristics, and the slightly non-uniform electric field of SF6 gas circuit breaker arc quenching chamber under different opening strokes is featured with scale-free and small-world properties, which belong to the features of complex network. The research results indicate: the network construction through the field visibility method has inherited some characteristics of electric field. By introducing the complex network theory, the electric field distribution can be studied from a new perspective.
Fog Removal from Color Images using Contrast Limited Adaptive Histogram Equalization

The images degraded by fog suffer from poor contrast. In order to remove fog effect, a Contrast Limited Adaptive Histogram Equalization (CLAHE)-based method is presented in this paper. This method establishes a maximum value to clip the histogram and redistributes the clipped pixels equally to each gray-level. It can limit the noise while enhancing the image contrast. In our method, firstly, the original image is converted from RGB to HSI. Secondly, the intensity component of the HSI image is processed by CLAHE. Finally, the HSI image is converted back to RGB image. To evaluate the effectiveness of the proposed method, we experiment with a color image degraded by fog and apply the edge detection to the image. The results show that our method is effective in comparison with traditional methods.
Implementation of a closed-loop growth scheme for AlAs-GaAs distributed Bragg reflector (DBR) structures using in situ pyrometric interferometry monitoring

We have investigated a closed-loop control system for molecular beam epitaxial growth of quarter-wavelength AlAs-GaAs distributed Bragg reflector (DBR) structures using in situ pyrometric interferometry. The quasi-sinusoidal PI data was being treated as an amplitude and phase modulated signal for control of layer thickness. Highly reproducible PI signals were obtained without the need of careful growth rate calibration. This technique can be useful in achieving reproducible growth of DBR structures, including vertical cavity surface emitting lasers.
2.5 Gb/s repeaterless optical transmission over 200 km single mode fiber with EDFA

We performed an analysis of the properties of high speed long haul IM/DD optical fiber transmission systems. The experimental results show a 2.5 Gb/s IM/DD optical fiber transmission over a 200 km conventional single mode fiber with an erbium doped fibre amplifier (EDFA) booster and an EDFA preamplifier. The sensitivity of the optical receiver with an EDFA preamplifier reached -39.8 dBm at a BER=1/spl times/10/sup -10/.
MemNet: A Persistent Memory Network for Image Restoration

Recently, very deep convolutional neural networks (CNNs) have been attracting considerable attention in image restoration. However, as the depth grows, the longterm dependency problem is rarely realized for these very deep models, which results in the prior states/layers having little influence on the subsequent ones. Motivated by the fact that human thoughts have persistency, we propose a very deep persistent memory network (MemNet) that introduces a memory block, consisting of a recursive unit and a gate unit, to explicitly mine persistent memory through an adaptive learning process. The recursive unit learns multi-level representations of the current state under different receptive fields. The representations and the outputs from the previous memory blocks are concatenated and sent to the gate unit, which adaptively controls how much of the previous states should be reserved, and decides how much of the current state should be stored. We apply MemNet to three image restoration tasks, i.e., image denosing, super-resolution and JPEG deblocking. Comprehensive experiments demonstrate the necessity of the MemNet and its unanimous superiority on all three tasks over the state of the arts. Code is available at https://github.com/tyshiwo/MemNet.
Effect of space charge on electric field for a vacuum interrupter

In this paper, for reflecting the distribution of electric field with post-arc charged particles, the electric field model based on the variation of the space charges of a vacuum interrupter has been established and calculated using the finite element method (FEM). In computing, the effects of floating shield and Hick open boundary on the charged electric field distribution have been taken into considerations, respectively. The distributions of electric field varying with the different distribution of space charges within the region of the contacts and between the contacts and floating shielding cover after current zero. have been clearly reflected. By comparison with different simulation results, the influence of space charges on the distribution of electric field during the breaking of vacuum interrupter has been studied and illustrated in this paper.
High-power calibration and measurement method for bio-electromagnetic study

A novel method for high-power calibration/measurement is presented in this work. This method employs a coupler and a dipole antenna to achieve high-power measurement. The coupler serves as a low-power sensor, whereas the dipole antenna is responsible for the high-power measurement. This method successfully calibrated a 600 W 13.56 MHz radio frequency generator and is potentially useful for even higher power measurement, as well as for hazardous high-intensity electromagnetic environment measurement, avoiding the use of expensive high-power metres.
Design of tri-reflector Compact Antenna Test Range for millimetre/sub-millimetre wave and THz antenna measurement

The Compact Antenna Test Range (CATR), which generates a pseudo-plane wave in a very short distance, is commonly employed to measure electrically large aperture antennas for the applications in space remote sensing and radio astronomy. With the increasing operating frequencies, the design of a CATR becomes a technical challenge. This paper presents the designs of two tri-reflector CATRs operating at 200 GHz: a Cassegrain-Gregorian (CG) configuration and a Double Gregorian (DG) one, through a dynamic ray-tracing approach. Both of the designs utilise two shaped sub-reflectors and a spherical main reflector. The characteristics of the two designs were also verified by using a commercial Physical Optics package, GRASP version 9.
Face alignment via boosted ranking model

Face alignment seeks to deform a face model to match it with the features of the image of a face by optimizing an appropriate cost function. We propose a new face model that is aligned by maximizing a score function, which we learn from training data, and that we impose to be concave. We show that this problem can be reduced to learning a classifier that is able to say whether or not by switching from one alignment to a new one, the model is approaching the correct fitting. This relates to the ranking problem where a number of instances need to be ordered. For training the model, we propose to extend GentleBoost [23] to rank-learning. Extensive experimentation shows the superiority of this approach to other learning paradigms, and demonstrates that this model exceeds the alignment performance of the state-of-the-art.
Investigation on electric field computation of vacuum interrupter using hybrid finite element method and charge simulation method

A parallel combined method of finite element method (FEM) and charge simulation method (CSM) is proposed, and a domain decomposition approach is employed to calculate the electric field of a vacuum interrupter. Calculation results of multi-dielectrics and intricate unbounded domain based on the combined FEM-CSM is of higher accuracy, less storage, easier equation solution, faster computation and more robust than conventional FEM or CSM approaches.
Numerical synthesis of tri-reflector CATR with high cross-polarisation isolation

In this Letter, a tri-reflector compact antenna test range (CATR) with a paraboloidal main reflector and two shaped sub-reflectors is synthesised by the kinematic and dynamic ray tracing method, while the high cross-polarisation isolation is achieved through the proposed system geometry. Numerical simulations by general responsibility assignment software patterns demonstrate that a cross-polarisation isolation >40 dB and a peak-to-peak amplitude (phase) ripple <1 dB (10°) can be achieved on the principal cuts of the designed quiet zone at 90–325 GHz. This clearly shows that the high cross-polarisation isolation in such a tri-reflector CATR can be achieved by the proposed antenna geometry without depolarisation control in the shaping procedure.
An investigate of mass diagnosis in mammogram with random forest

Correct mass diagnosis in mammogram can reduce the unnecessary biopsy without increasing false negatives. In this paper, we investigated the usage of random forest classifier for the classification of masses with geometry and texture features. Before extracting features, the mass regions need to be extracted. Based on the initial contour guided by radiologist, level set segmentation is used to deform the contour and achieves the final segmentation. The proposed level set method integrated both region information and boundary information, and with a level regularization term, it can achieve accurate segmentation. Modified Hu moments were used for shape characteristics, and GLCM (Gray Level Co-occurrence Matrix) features are used for texture characteristics. Random forest, a recently proposed ensemble learning method, for the first time, is investigated for the mass classification, and is compared with SVM (Support Vector Machine). Mammography images from DDSM were used for experiment. The new method based on the level set segmentation and the features achieved a Az value of 0.86 with SVM and 0.83 with random forest. The experimental result shows that random forest is a promising method for the diagnosis of masses.