nils-herrmann/clean_scirepeval huggingface dataset:
A hydrophone array calibration method for Multibeam Echo Sounder

The side-lobe level is an important factor that determines the performance of the Multibeam Echo Sounders. In order to keep the side-lobes down, the magnitude and phase discrepancies must be compensated prior to the beamforming operation. In this paper, a calibration method of MBES's received array is proposed. This method can be implemented in room other than an open water area., and it doesn't require standard hydrophones or the high precise measurement-equipment. In the paper, a received array of MBES, whose frequency is 200 kHz, is calibrated, and the results have shown that the decreased of the side-lobe level could be as low as 9-12 dB.
A robust triangular-electrode based capacitive detection method for MEMS gyroscopes

This paper presents a robust triangular-electrode based (TEB) capacitive detection method for MEMS gyroscopes. The TEB method utilizes the inherent nonlinearity of TEB variable-area sense capacitor to measure the amplitude and the phase of mechanical motion, and the derived amplitude and phase are independent of such system parameters as the carrier voltage, the nominal sense capacitance, the gain or phase shift in C/V circuit. As a result, gyroscope outputs and their scale factor are robust to system parameter fluctuations using TEB method. Working principles and robustness are compared between linear-EAM method and TEB method to manifest the superiority of TEB method. Finally, the TEB method is implemented in an FPGA-based PCB with a MEMS gyroscope. Experimental results verify the theoretical analysis and demonstrate that the sensitivity of the scale factor on carrier voltage variations is highly suppressed up to 99.77% using TEB method. In addition, the offset drift of gyroscope output on circuit phase shift variations is greatly suppressed up to 99.96% by virtue of TEB control. Allan variance analysis demonstrates a bias instability of 4.0 °/h, and an ARW of 0.32 °/√h at atmosphere.
Data compression of light field using wavelet packet

A disparity-compensated compression scheme for light fields is presented. In contrast to prior disparity-compensated based codecs we perform disparity estimating and image predicting in subbands not directly in the original images. In our approach, firstly the original images are decomposed into subbands using the wavelet packet transform, and then the corresponding wavelet packet bases are divided into predictable bases and unpredictable bases by some criteria. In coding, the hierarchical structure proposed by Magnor (1999) is used, and the subbands corresponding to the predictable and unpredictable basis are added sequentially by relative energy until the reconstructed images meet the pre-established reconstruction quality. Except for high compression ratios our approach also provides scalability to some extent. Experiments for two standard light fields verify the efficiency of our approach
Early-Warning System With Quasi-Distributed Fiber Optic Sensor Networks and Cloud Computing for Soil Slopes

Slope failure and debris flow cause lots of casualties and property loss. An early-warning system for slope collapse and debris flow is essential to ensure safety of human beings and assets. Based on fiber optic sensing technology and Internet of Things, a new sensing transducer for internal earth pressure measurement in a soil slope is proposed, fabricated, and tested in this paper. The working principles, theoretical analysis, laboratory calibrations, and discussions of the proposed pressure transducers are elaborated. Extensive evaluations of the resolutions, physical properties, and response to the applied pressures have been performed through modeling and experimentations. The results show that the sensitivity of the designed pressure sensor is 0.1287 kPa/ $\mu \varepsilon $  across a pressure range of 140 kPa. Finally, a field soil slope was instrumented with the developed fiber optic sensors and other sensors. Through internet and cloud computing platform, the stability of the soil slope was analyzed. In the cloud computing platform, the numerical simulation is carried out by considering the slope internal deformations, rainfall infiltration, and limit force equilibrium. The factor of safety of the soil slope was calculated, which could be used to determine health condition of the instrumented slope. The performance was evaluated and classified into three categories. It proves that the proposed early-warning system has potential to monitor the health condition of the soil slopes.
A Time-Series Based Precopy Approach for Live Migration of Virtual Machines

As an important technique for load balancing in cloud computing, live migration of virtual machines has received increasing attention in recent years. One key issue of live migration of virtual machine is how to quickly and transparently migrate virtual machines to meet Service Level Agreements (SLAs). In this paper, we evaluate traditional precopy approach, and propose an improved time-series based precopy approach for virtual machine migration. With the time-series prediction technique, we identify frequently updated dirty pages (high dirty pages) in the past and future period more precisely, and transmit them in the last round of iteration, in order to reduce unnecessary, repeated transmission of dirty pages. Doing so can significantly reduce the total migration time. Simulation results show that compared with the traditional approach of Xen, our approach can effectively improve the performance of virtual machine migration, including less number of iterations, less down time and migration time, and fewer pages transferred.
Implementation of Hodgkin-Huxley neuron model in FPGAs

In this paper, the biophysically plausible neuron model i.e. the Hodgkin-Huxley neuron model has been implemented in the field programmable gate arrays (FPGAs) by employing Altera DSP Builder. The action potential generated by Hodgkin-Huxley neurons implemented in FPGA has been compared with the numerical prediction, leading to a good agreement between them. It is believed that this approach could greatly speed up simulations of both highly complex single neuron model and network of neurons.
Compact Smart Antenna With Electronic Beam-Switching and Reconfigurable Polarizations

This paper presents a compact-size, low-cost smart antenna with electronically switchable radiation patterns, and reconfigurable polarizations. This antenna can be dynamically switched to realize three different polarizations including two orthogonal linear polarizations and one diagonally linear polarization. By closely placing several electronically reconfigurable parasitic elements around the driven antenna, the beam switching can be achieved in any of the three polarization states. In this design, a polarization reconfigurable square patch antenna with a simple feeding network is used as the driven element. The parasitic element is composed of a printed dipole with a PIN diode. Using different combinations of PIN diode on/off states, the radiation pattern can be switched toward different directions to cover an angle range of 0° to 360° in the azimuth plane. The concept is confirmed by a series of measurements. This smart antenna has the advantages of compact size, low cost, low power consumption, reconfigurable polarizations, and beams.
A MEMS-based ionization gas sensor using carbon nanotubes and dielectric barrier

We have demonstrated here the successful operation of an ionization gas sensor with gap spacing 2~10 mum and using CNTs (carbon nanotubes) as the electrode material. By set up an appropriate threshold current, the application of less than 20 V DC bias could generate electric field enough to effectively ionize various gases in atmospheric pressure. Working by the fingerprinting ionization characteristics of distinct gases, the sensor can effectively distinguish several gases by their various breakdown voltages and serves as an effective human breath monitor. TiO2 dielectric barrier is introduced to the discharging system to improve the performance of the device. Experimental tests prove that with the dielectric barrier discharge mechanism has improved both the stability and ionization capability of the device.
A ergonomics evaluation hierarchy for the typical manually controlled devices in spaceflight

Ergonomic evaluation of manually controlled devices is an important means of testing a man - machine interface matching in manned space medicine and engineering research. It's one of the comprehensive evaluation method based on Delphi, AHP and Grey systems. This study proposed a mathematical model combining subjective weights and objective weights, evaluated manually controlled devices quantitatively, solved the connection between design features and an operator satisfaction. Furthermore, by conducting a real experiment with both bare hand and glove box means, it analyzed the operation of the typical manually controlled devices, and verified the feasibility of a comprehensive evaluation and effectiveness of subjective and objective indices.
A density-awareness and delay-sensitive data collecting scheme for wireless sensor networks

This paper proposed a density-awareness and delay-sensitive (DADS) data collecting scheme for wireless sensor networks. This scheme exploits static sink and mobile sink simultaneously to collect data from the whole network. In this way, DADS can solve the premature network partition problem, resulting from the heavy traffic load in the static sink's vicinity. On the other hand, the coexistence of static sink can guarantee the delay of data delivery for source nodes cannot wait to send their data until the arrival of mobile sink. Comparing with existing algorithms, the major contributions of DADS lies in, (1) mobile sink can adapt the TTL (broadcast depth) of new position announcement message according to the corresponding node density, such that performance can be improved significantly in terms of packet delay and packet delivery ratio without sacrifice of energy consumption balance in the whole network, (2) if a source node only has the route to static sink, packets originated from it may be redirected to the nearer mobile sink when pass through immediate node, this minor and unapparent upgrade can even further improve the state of the art in terms of the referring performance metrics. Finally, extensive simulations show that DADS outperforms the existing data collecting scheme in terms of packet delay, data delivery ratio and network lifetime.
Action recognition using context and appearance distribution features

We first propose a new spatio-temporal context distribution feature of interest points for human action recognition. Each action video is expressed as a set of relative XYT coordinates between pairwise interest points in a local region. We learn a global GMM (referred to as Universal Background Model, UBM) using the relative coordinate features from all the training videos, and then represent each video as the normalized parameters of a video-specific GMM adapted from the global GMM. In order to capture the spatio-temporal relationships at different levels, multiple GMMs are utilized to describe the context distributions of interest points over multi-scale local regions. To describe the appearance information of an action video, we also propose to use GMM to characterize the distribution of local appearance features from the cuboids centered around the interest points. Accordingly, an action video can be represented by two types of distribution features: 1) multiple GMM distributions of spatio-temporal context; 2) GMM distribution of local video appearance. To effectively fuse these two types of heterogeneous and complementary distribution features, we additionally propose a new learning algorithm, called Multiple Kernel Learning with Augmented Features (AFMKL), to learn an adapted classifier based on multiple kernels and the pre-learned classifiers of other action classes. Extensive experiments on KTH, multi-view IXMAS and complex UCF sports datasets demonstrate that our method generally achieves higher recognition accuracy than other state-of-the-art methods.
Computer-aided design of octo-filar helix antennas with fixed arm length

An octo-filar helix antenna that can form a backfire or endfire conical beam by changing its pitch angle and feeding modes with its arm length invariable is researched by the Nakano integral equation and the method of moments. A shaped-conical radiation pattern with good circular polarization performance and the best beam conformity can be obtained for almost all the hemisphere. Comparison of the radiation properties, including the beam direction, maximum power gain and 3-dB axial ratio angle coverage under different feeding modes is conducted. The relationship between the pitch angle and the height of the satellite orbit is also presented, which provides theoretical references for the design of the antenna.
Fast Transcoding from H.264 AVC to High Efficiency Video Coding

In this paper, we present several strategies for transcoding from H.264/AVC bit streams to High Efficiency Video Coding (HEVC) bit streams. Because HEVC and AVC share the similar coding architecture, we try to exploit the information in AVC bit streams as much as possible. For inter picture, we utilize the power spectrum based rate-distortion optimization (PS-RDO) model as well as the input residual, modes and motion vectors to estimate the best coding unit (CU) split quad tree, the best prediction unit (PU) mode and the best motion vector of each PU partition For intra picture, we propose to reduce the CU and PU partition candidates. The proposed strategies can significantly reduce the transcoding complexity in terms of reduced processing for RDO evaluations, motion estimation, motion compensation as well as fractional pixel interpolation operations. Experiment results show that the proposed transcoding methods can achieve a good tradeoff between coding efficiency and transcoding complexity.
Improved front side metallization for silicon solar cells by direct printing

This work presents a direct printing technology and an enabling tool for forming very fine gridlines with high aspect ratios that improve the front side metallization of silicon solar cells. The parallel printing setup is anticipated to print each cell in two seconds. The conductive gridlines were formed by a one-step non-contact approach at high speeds using a modified standard screen printable paste. The line width is as small as 40µm, and the line thickness is more than 30µm after firing. The front shading area is significantly reduced, and a previous study has demonstrated up to 0.5% absolute cell efficiency increase as compared to the screen-printing process baseline when the same grid pattern was used. Due to further reduction of grid line width, the pitch between each grid line increases, which affects the travel distance of the electrons excited by photon interaction, which affects the fill factor and ultimately the efficiency of the cell. In addition to the previous comparison study of wafers using the same grid pattern, this study investigated the cell performance using a modified gridline pattern that has an increased number of gridlines. The results showed an absolute efficiency increase up to 0.7%. Other electrical attributes of direct printed high aspect ratio gridlines in terms of ISC, VOC, FF and other data are also presented.
Design of H∞-optimal robust controllers: Stability, asymptotic regulation and disturbance rejection

This paper introduces a new synthesis method, based on a computation method for solving a H¿-optimization problem1 and a new technique of "j-axis shifting" for designing a H∞ optimal robust controller for the SISO system. With this method, we can optimize the excess stability margin under the requirement that all poles of the nominal closed loop system (cl-system) be located at the left of the j-axis with a required distance d and ensure asymptotic regulation and disturbance rejection for a class of system input and disturbance if the plant perturbation does not exceed the excess stability margin. Another advantage is that there are no constraints to the poles and zeros of the plant when using this method.
Inductance-simulating control for DFIG-based wind turbine to ride-through grid faults

For doubly fed induction generator (DFIG)-based wind turbine (WT), large electromotive force will be induced in the rotor circuit under grid faults, and the rotor side of DFIG is prone to suffering from overcurrent and overvoltage. To mitigate this problem, an inductance-simulating control strategy is proposed to enhance its low-voltage ride through (LVRT) capability. In this method, the rotor side converter (RSC) is controlled to simulating as an inductance. Furthermore, under proper inductance value, both the required rotor voltage and post-fault rotor current can be reduced within the permissible range. In addition, the electromagnetic torque ripple can be effectively eliminated. Finally, the simulation and experimental results clearly demonstrate the effectiveness of the proposed method.
A novel push-pull forward converter for high reliability and high input voltage applications

A novel push-pull forward converter (PPFC) is proposed in this paper. The converter is constructed by series connecting and coupling two forward converter cells via an integrated magnetizing core. Switches' voltage stress of this converter is clamped at input voltage and the leakage energy and magnetizing energy of the transformer are recycled. In addition, high reliability can be guaranteed since no direct-short path existed in the converter, which is the main consideration for applications where high-reliability is required, i.e. space and aircraft applications. All these features make the proposed PPFC suitable for high-reliability, high-input voltage, high power density power conversion applications. Operation principle and detailed analysis of the proposed converter are given and verified with experimental results. Furthermore, the topology principle is extended with another PPFC topology proposed based on the full-bridge converter.
Current characteristic of high voltage capacitor charging power supply using a series resonant topology

Pulse power supply applications usually require short and intense bursts of energy that may be derived by rapidly discharging an energy storage capacitor. Series resonant topology is used in capacitor charging power supply because of its approximate constant current characteristic from zero volts to maximum voltage. But the series resonant topology with open-loop control is not accurate constant current charging characteristic because the DC bus voltage is variable and the transformer is not ideal. Furthermore, the high voltage rectifier diodes are also not ideal. This paper presents the current characteristic of series resonant power supply with ideal and actual components, respectively. And moreover, some valuable figures given in this paper can be used during the course of designing and debugging.
An Environmental Automatic Monitoring System for Heavy Metals

An automatic monitoring system was developed for simultaneous determination of trace zinc, cadmium, lead, copper, iron and arsenic in environmental aqueous media using electrochemical stripping voltammetry. The sensor was mercury-film silver-based electrode. With a potentiostat, several pumps and valves controlled by computer, the system realized in-situ real-time detection of the six heavy metal ions mentioned above without manual operation. Quantitative heavy metals analysis at parts-per-billion level was performed by standard addition method. One measurement can be completed in 20 min with only 10 ml sample.
A post-compensation scheme for Nonlocal Means filter based image restoration

Recent nonlocal means filter (NLM)  is lack of mean conservation property, that is, image can have different mean before and after being processed. It is not suppose to happen when dealing with zero-mean noise. In this paper, a compensation procedure is proposed as post-process of NLM. The constraint of mean conservation is imposed on NLM through adding to the restored image of NLM with a compensation image. The compensation image is obtained via processing the method noise of NLM. Experiments show that the compensation procedure is able to significantly improve the performance of NLM.
A miniaturized fermi TSA with improved radiation characteristics For UWB Application

A miniaturized Fermi tapered slot antenna for Ultra-Wide Band application is proposed in this paper. Fermi tapering profile (FTP) and tapered slot load (TSL) are employed in the design. FTP has the capacity to narrow radiation beam and maintain good directivity. TSL could extend the impedance bandwidth by broking physical limitation and improve the radiation characteristics in the lower frequencies as well. A prototype of the presented antenna has been fabricated and experimentally studied. The measured results have demonstrated to have a impedance bandwidth from 2.77 GHz to over 12 GHz. Highly directive patterns have also been observed in both E-plane and H-plane. Furthermore, a high gain varies from 6.18 to 10.79 dB in the working bandwidth of 3 GHz-12 GHz.
First report of scaling a normally-off in-situ oxide, GaN interlayer based vertical trench MOSFET (OG-FET)

GaN lateral transistors (HEMTs) continue to penetrate the power electronics market demonstrating excellent performance in the medium power applications. However, for power applications 10kW and higher, vertical GaN devices are preferred over lateral one, since the former offers higher current and power densities. To date, several different vertical transistor structures have been proposed and reported, such as in-situ oxide based vertical trench MOSFET with an undoped GaN interlayer as a channel (OGFET) [1, 2], current aperture vertical electron transistors (CAVETs) , junction field effect transistors (JFETs) [5, 6] and MOSFETs [7, 8]. Gupta et al. have demonstrated the high performance OGFET with low specific on-state resistance (Ron, sp) recently . This study presents the large device scaling of the OGFET to realize high output current.
A suboptimal user selection algorithm for wireless broadcast channels

In downlink broadcast channels, the multiple-antenna base station (BS) often communicates with several users simultaneously. However, the co-channel interference increases as the number of users increases, therefore, BS can not afford too many users. So user selection is necessary. In this paper, we propose a suboptimal user selection algorithm based on signal-to-leakage-noise ratio (SLNR) for the wireless broadcast systems. The property of the proposed user selection algorithm is studied compared with some other selection algorithms in conjunction with the SLNR precoding. Simulation results show that the performance of the proposed algorithm is close to that of the optimal one. For fairness, the impact of scheduling algorithm is also considered.
A dynamic slice control scheme for slice-parallel video encoding

Slice-parallel video coding with a fixed number of slices and uniformly allocated coding regions would cause extra waiting time among slice threads, especially when the encoding machine is also busy running other applications. In this paper, we propose to adaptively decide the number of slices before encoding each frame by computing the expected value of the coding time of the encoder under two kinds of machine states: busy and free based on a Markov system. We also manage to balance computational complexity among slices by utilizing the estimated encoding time of each allocation unit in the frame to be encoded. Experimental results show that the proposed scheme can further improve the coding speed of an H.264 based fixed-slice parallel encoder by 30% on average, while the rate-distortion performance change is marginal.