nils-herrmann/clean_scirepeval huggingface dataset:
Research on the Universal Platform for Aerospace Craft Simulation

A universal platform for aerospace craft simulation was proposed in order to satisfy the various requirements in space tasks simulation. The platform is composed of a series of modular and standardized simulators, in which the kinematic, optic, radar or other characters of crafts can be simulated. The command & control functions and task programming processes can also be simulated in either accurate mode or rough mode. The platform can simulate simple tasks using only one simulator or complex contributed tasks using multi-simulators. As a whole, the proposed platform can be used as a flexible infrastructure to simulate various space tasks.
Hardware JPEG Decoder and Efficient Post-Processing Functions for Embedded Application

In this paper, a hardware JPEG decoder with three post-processing functions is proposed for embedded application. This decoder could decode the sequential JPEG image except for arithmetic encoding and 12bit sample precision. The post-processing functions - Inner Down-Scaling (IDS), Region-Of-Interest (ROI) decoding and Partial DeCoding (PDC) are employed to make an efficient post-processing for the embedded applications. It is a fully pipelined design with friendly interface, which makes it easier to be integrated into the SoC system. The decoder has been implemented with TSMC 55nm technology. The equivalent gate count including memories is about 206K and the max work frequency is about 325MHz.
Control strategy of wind turbine based on permanent magnet synchronous generator and energy storage for stand-alone systems

This paper investigates a variable speed wind turbine based on permanent magnet synchronous generator and a full-scale power converter in a stand-alone system. An energy storage system(ESS) including battery and fuel cell-electrolyzer combination is connected to the DC link of the full-scale power converter through the power electronics interface. Wind is the primary power source of the system, the battery and FC-electrolyzer combination is used as a backup and a long-term storage system to provide or absorb power in the stand-alone system, respectively. In this paper, a control strategy is proposed for the operation of this variable speed wind turbine in a stand-alone system, where the generator-side converter and the ESS operate together to meet the demand of the loads. This control strategy is competent for supporting the variation of the loads or wind speed and limiting the DC-link voltage of the full-scale power converter in a small range. A simulation model of a variable speed wind turbine in a stand-alone system is developed using the simulation tool of PSCAD/EMTDC. The dynamic performance of the stand-alone wind turbine system and the proposed control strategy is assessed and emphasized with the simulation results.
Estimation of Local Attenuation and Its Application to Rationalized Gain Control

The aim of this paper is to provide a local attenuation estimation algorithm from ultrasound images. Using the computed attenuation coefficients locally, we define a 2-D table for tissue attenuation compensation in the sense of a rationalized gain control. To handle the frequency shift in the broadband system, we use nonlinear least squares (NLS) data fitting directly to the local amplitude changes due to the tissue attenuation. By looking at the convergence of the NLS method, e.g., the Levenberg-Marquardt algorithm, we proposed a technique to test the possible tissue heterogeneity locally. Algorithms have been verified both in phantom and in vivo images. Results showed that the proposed method can have at most 4% relative error in estimating attenuation coefficients of phantom images in a broadband system. It also showed a uniform in vivo image after the proposed rationalized gain control.
Nonrandom quantization errors in timebases

Timebase distortion causes nonlinear distortion of waveforms measured by sampling instruments. When such instruments are used to measure the RMS amplitude of the sampled waveforms, such distortions result in errors in the measured RMS values. This paper looks at the nature of the errors that result from nonrandom quantization errors in an instrument timebase circuit. Simulations and measurements on a sampling voltmeter show that the errors in measured RMS amplitude have a nonnormal probability distribution, such that the probability of large errors is much greater than would be expected from the usual quantization noise model. A novel timebase compensation method is proposed which makes the measured RMS errors normally distributed and reduces their standard deviation by a factor of 25. This compensation method was applied to a sampling voltmeter and the improved accuracy was realized.
Second-order time-varying sliding mode control for uncertain systems

A novel second-order time-varying sliding mode control(SOTVSMC) law is proposed for the robust tracking control problem of nonlinear smooth single-input single-output(SISO) system with disturbance. The advantages of the proposed SOTVSMC are twofold. The global second order sliding mode is established, which implies that the closed-loop system is global robust against matched parameter uncertainties and disturbances. Meanwhile, the chattering problem is significantly alleviated. Then the parameter of the sliding mode is obtained by solving an optimal problem. Finally, the effectiveness and robustness of the control strategy is demonstrated by simulation results.
Research on Customer Value Classification Based on Improved Support Vector Machine

Aimed at the shortages of the existing data-mining model for classification of customer, this paper proposed a new customer classification model based on rough sets and support vector machine. First, the theory of rough set was applied to pick up and reduce the index attributes. Then, the training samples were sent to the support vector machine to train and learn. After that, the sorts of the customers in test samples were determined. The test results indicate that the new customer classification model based on rough sets and support vector machine shows the higher forecast precision than the traditional customer classification models and it is more efficient and practical.
Formal modeling and verification of smart distribution grid based on common information model

The expanding smart distribution grid with gradually updating business modes is requiring a superior information model to reflect its state precisely. This paper proposed a formal modeling and verification method based on common information model. Considering the imprecision and ambiguity of UML in the modeling process, we constructed the formal definitions and logical descriptions for objects, logics and scenes of the information model, followed by the derivation of ontology rules and propositions. To verify whether the model possesses the expected semantic features, formal verification method is generalized using underlying logics and semantics derived from the ontology rules. Later on, the formal verification tool SPIN is applied to the distribution control area model as an example for formal verification to ensure the synchronization of semantics and structure for data exchange process between information models. a)The formal symbols in this paper adopt the following conventions: b)The formal expressions conform with Backus Naur form, BNF; c)The capital letters represent sets, lowercase letters denote the elements: tϵT; Definitions use the combination of numbers: 2-3; Rules use number and uppercase letter combination: 2-A; Inference use number and lowercase letter combination: 2-d.
Simulative Design of Electromagnetic Tomography Sensor on Double-Frequency Excitation Mode

Electromagnetic tomography (EMT) is a kind of electric tomography in combining with electromagnetic induction principles and computerized tomography. It is widely studied and applied in biomedical and industrial area recently. EMT sensor has advantages of non-invasion, non-contact and non-hazard. The paper aims to work on design of EMT sensor on double-frequency excitation. EMT sensor adopts eight coils distributed homogenously out of measuring pipe. The sensing field model is set up based on electromagnetic induction principle and the simulation is practiced in COMSOL Multiphysics. The relation between position information, conductivity and permeability of object and measurement electric potential are presented and analyzed in the paper. The diameters of screen and coils are simulated in the paper. Simulative result of EMT sensor describes the relation map of between sensing field and measurement voltage and provides useful prior information for design of EMT system.
Four-dimensional Ultrasonography Measured Lung Volume in Predicting Pulmonary Hypoplasia of Fetus

To observe the feasibility of virtual organ computer-aided analysis (VOCAL) technique in estimating the fetal lung volume, and to assess the diagnostic value of ultrasound fetal lung volume in fetal pulmonary hypoplasia (PH).  A total of 31 fetuses (20-32 weeks) with abnomal diagnosed with prenatal ultrasonography were enrolled in this study. The autopsy and clnical diagnosis were permitted. The fetal lung volume was estimated with four-dimensional ultrasonography using VOCAL technique, the value of fetal lung volume in the diagnosis of fetal PH was evaluated.  The sensitivity value of fetal lung volume in diagnosing fetal PH was 81.1% and the accuracy ratio was 76.92%.  The fetal lung volume can be estimated precisely with four-dimensional ultrasonography using VOCAL technique. Fetal lung volume may be useful in the prenatal diagnosis of fetal PH.
Boost search relevance for tag-based social image retrieval

Social media sharing web sites like Flickr allow users to annotate images with free tags, which greatly facilitate social image search and browsing. However, currently tag-based image search on Flickr does not provide the option of relevance-based ranking, i.e., the search results cannot be ranked according to their relevance levels with respect to the query tag, and this has limited the effectiveness of tagbased search. In this paper, we propose a relevance-based ranking scheme for social image search, aiming to automatically rank images according to their relevance to the query tag. It integrates both the visual consistency between images and the semantic correlation between tags in a unified optimization framework. We propose an iterative method to solve the optimization problem, and the relevancebased ranking can thus be accomplished. Experimental results on real Flickr image collection demonstrate the effectiveness of the proposed approach.
Robust adaptive dynamic programming for a zero-sum differential game

This paper presents a novel model-free online algorithm to solve the linear continuous-time three-player zero-sum differential game problem in the presence of dynamic uncertainty. Based on robust adaptive dynamic programming (RADP) method, the saddle point control policy and disturbance policy are iteratively approximated for the game problem with unmatched uncertainties. The convergence of the proposed RADP method and the global asymptotic stability (GAS) of the closed-loop system are also analyzed. An application to a power system is adopted to illustrate the effectiveness of the derived algorithm.
Fast assessment of SAR in SAM phantom exposed to a handset antenna

Since the diversification of the electromagnetic (EM) environment is spreading, it is essential to estimate the EM energy absorption rate (SAR) of human's body especially human's head under various exposure situations. A novel method is presented that accurately and quickly estimates the SAR in a specific anthropomorphic mannequin (SAM) phantom by using SAR in a double layered prolate head model with a compensating function. Comparison of SAR induced in a double layered prolate head model and a specific SAM head model was investigated firstly, and the systematic biases resulting from shape effect of the SAM and prolate head model is obtained in different position cases. Then a hybrid Null Field Method / Method of Moments (NFM/MoM) approach is used to analysis EM problem for a double layered prolate head model exposed to a handset antenna. By means of the hybrid approach, the MoM is applied to a handset antenna, and the NFM is used to model the scattering problem from the head model. The electromagnetic coupling between the head model and an antenna is taken into account by a fast convergent iteration process. The numerical results show that the proposed method is able to estimate SAR in SAM head model within an error ±6% for dual band PIFA antenna, which indicate the possibility to quickly assess electromagnetic radiation to human head using double layered prolate model.
The closed-form compliance equations for combined-parabola-shaped flexure hinge based on the unit-load method

A new type of flexure hinge, called combined-parabola-shaped flexure hinge, is presented in this paper. The closed-form compliance equations of the flexure hinge are derived based on the unit-load method. Based on the compliance equations, the numerical simulation is conducted to discuss the performance of the flexure hinge. The results indicate that, the stiffness of the combined-parabola-shaped flexure hinge decreases as s1 increases, increases as t increases. It possesses the ability to change its motion accuracy and its compliance, which means that it can meet variety requirements in engineering applications.
Research of Spectrophotometer for Bio-Chemical Analyzer Based on Automatic Adjustment of the Integration Time of Linear CCD

The bio-chemical analyzer (BCA) is a kind of instrument which is used to measure some clinical or chemical targets in samples (blood). Since light source's energy is different and samples have different spectrum absorbance in different wavelength. Energy attenuation of ultraviolet (UV) wavelength is large; otherwise, The noise which exist in the electronic circuits and the astigmatism which exist in the ray-route system ,both of which will reduce the luminosity nicety in the UV wave-band. In this paper, Virtual Instrument(VI) technique and the method of software optimizing algorithm are used to enhance measurement veracity of the luminosity value, and the exposure time of linear CCD is auto-adjusted to expose separately for strong light and week light. From experiment results , we can obtain that the capability and signal to noise ratio (SNR) of the system are greatly improved , the spectrum range of spectrophotometer for BCA can reach 300~800 nm and the distinguish of wavelength is less than 10 nm.
A new text feature extraction model and its application in document copy detection

Text feature extraction is a common issue in information retrieval, text mining, Web mining, text classification/clustering and document copy etc. The most popular approach is word frequency based scheme, which uses a word frequency vector to represent a document. Cosine function, dot product and proportion function are regular similarity measures of vector. But that is only global semantic feature of a document and loses local feature and structural information so that it prevents us to distinguish text well, especially in copy detection. In this paper we present a new text feature extraction model: semantic sequence model (SSM) that based on the concepts of word distance, word density and semantic sequence. The semantic sequences of a document contain not only local semantic features but also global feature and structural information, on which we get excellent accuracy of text copy detection. At the end of the paper, we contrast SSM with VSM and RFM and the experimental results show SSM is a superior model.
Improved wideband beamforming algorithm based on microphone arrays

In this paper, the wideband beamforming based on microphone arrays(MA) is investigated. This method combined the technologies of frequency focusing and sub-band partitioning. The frequency focusing algorithm is to focus the wideband signals to the narrowband signals at the reference frequency. But this algorithm only applies for the signals with fractional bandwidth less than 1.25. The improved focusing algorithm divides the frequency band of signals into several sub-bands to decrease the fractional bandwidth. It reduces the computational complexity without loss of focus error.
A Monolithic Low-Distortion Low-Loss Silicon-on-Glass Varactor-Tuned Filter With Optimized Biasing

A low-distortion varactor-tuned bandpass filter is demonstrated on a high-Q silicon-on-glass technology. The dc bias network is optimized to achieve high linearity, the center frequency of the filter tunes from 2.4 to 3.5 GHz, and the measured loss of the filter is 2-3 dB at 2 GHz, with a stopband rejection of 25 dB. The measured IIP3 of the filter was +46 dBm
Demonstration of THz communication based on 0.5THz superconducting SIS receiver

Thanks to its high frequency, THz wave is very suitable for ultra-broadband and high data rate communications. Because transmission of THz signal is seriously affected by atmosphere, especially water vapor, more sensitive THz detection techniques are essential for efficient and long-distance THz communications. Based on 0.5THz superconducting SIS receiver, demonstration of THz communication including FM Gaussian noise and FM square wave signal is introduced in this paper. In the experiment, receiving, spectrum processing and demodulation have been tested towards two types of signals, and the testing results will be given as well.
Notice of RetractionA Comparative Investigation of the Nitrosodimethylamine Formation from the Nitrosation of Dimethylamine and Trimethylamine by Nitrite under the Neutral Condition

The nitrosation reactions of dimethylamine (DMA) and trimethylamine (TMA) by nitrite to form carcinogenic nitrosodimethylamine (NDMA) were studied under the neutral condition. A comparative investigation of the amounts of NDMA formation from the nitrosation reaction of amines (DMA and TMA) by nitrite at various ratios of amine and nitrite in phosphate salt buffer (pH=6.4) at elevated temperature (90°C) was made. The results showed that, as varying the concentration of amine, the yields of NDMA from DMA are considerably higher than those from TMA when the ratio of amine to NO2- is in a range of 1:1 to 10:1, whereas the amounts of NDMA produced from TMA are obviously more than those from TMA when the ratio grows to 50:1 or more. Differently, as varying the concentration of nitrite, the amounts of NDMA formation from DMA are always more than from TMA when the ratio of nitrite to amine is in the range of 1:1 to 150:1.
Study on the relationship between highway system and urban heat island

This paper retrieves the land surface temperature by using Mono-window Algorithm from 1989, 2001, 2007 Landsat TM remote sensing images in Harbin; analyzes the distribution of land surface temperature and the relationship between highway system temperature and urban heat island with the topographic map in 1990s. Some research as followed: the temperature of highway is lower than surrounding area significantly. As a special corridor system, highway can separate and slow down the urban heat island. The effect of the railway in Harbin is no more than 300m range; the maximum cooling effect of highways on urban heat island is no more than 0.4°C, this effect is little or disappear after 120m. The effect of highways on heat island is obviously distinct in different directions, and highways with different greening rate can also make different effect on urban heat island.
Phase Compensated Reduced Order Generalized Integrators for Grid-Tied VSCs With Harmonics Compensation Capability

Current control is a crucial issue of the operation of grid-connected voltage source converters (VSCs). The challenge of the current control lies in how to track the current reference in a fast and accurate way. A second-order generalized integrators (SOGIs)-based current controller is one of the highly popular ways to achieve these objectives since they can track ac signals of both positive and negative frequencies/sequences without steady-state error. However, this may lead to extra unnecessary computational burden when SOGIs are applied in three-phase systems. Therefore, a reduced order generalized integrators (ROGIs)-based current controller is proposed to reduce the computational burden. In this paper, a phase compensation embedded ROGI is proposed, which can not only retain the advantage of a less computational burden of the conventional ROGI compared with the SOGI, but also more importantly, further improve the harmonic control bandwidth and frequency adaptivity in comparison with the SOGI or conventional ROGI. In addition, the derivation of the phase compensated ROGI is provided in the paper along with its parameters tuning strategy analysis. A case study regarding an LCL-filtered three-phase grid-connected VSC with auxiliary harmonic compensation capability is given in detail. Finally, the experimental results are presented to validate the superiority of the proposed method.
Study of Transformation and Chromosomal Instability of Human Tracheal Epithelial Cells Induced by Formaldehyde

To determine the mechanisms of chemical carcinogenesis, the relationship between malignant transformation and genome /chromosomal instability of human bronchial epithelial cell, cell line - BEAS-2B cell exposed to formaldehyde was studied.  The LC50 value of formaldehyde to BEAS-2B cells was tested by MTT assay. Then the cells were induced with formaldehyde at the concentration of 20% LC50; the characteristics of transformation of cells were identified though the characters of growth curve and colony formation rate of semi-solid agar. The metaphase modal chromosome numbers, karyotypes and nonrandom structural change of induced cell strains were analysed with the G-banding technique.  The growth curve of induced cells showed a trend of infinite proliferation and the anchorage independent growth was appeared in 15 generation cells. Before transformed, BEAS-2B cells had a pseudodiploid karyotype and were relatively stable genotypically. After transformed, three characteristic abnormal chromosomes were found. Most of the induced cells were triploid and/or tetraploid cells. The loss of one normal or two homologs of chromosome 14 also had a higher frequency. Furthermore, in their karyotypes, one or two unknown chromosomes appeared and trisomy-5 or trisomy-16 was observed. The induced cells also had a higher frequency of non-stabilizing aberration (39%), including chromosome loss, endoduplication, translocation, break, dicentromere and/or tricentromere etc.  Formaldehyde could contribute to progression of transformation and result in genome instability.
Modeling and Stability Analysis of VSC Internal Voltage in DC-Link Voltage Control Timescale

With increasing application of voltage source converters (VSCs), electromagnetic stability, characterized by fast dynamics and controls of electromagnetic elements such as inductors and capacitors, becomes challenging for power system stability. This paper investigates modeling and stability analysis of VSC internal voltage in dc-link voltage timescale. Concepts of VSC internal voltage inertia, damping power, and synchronizing power are introduced to provide a physical insight into VSC stability issue. Internal voltage stability can be identified by analyzing damping and synchronizing powers. Insufficient of either damping power or synchronizing power will result in loss of stability. Furthermore, internal voltage stability affected by short circuit ratio (SCR), operating point, and phase-locked loop (PLL) bandwidth is analyzed by investigating their effects on damping and synchronizing powers, respectively. It is found that internal voltage stability becomes deteriorated due to the insufficient damping power with low SCR values, high operating powers, and PLL bandwidth getting close to dc-link voltage control bandwidth in a weak grid. Simulation results and experimental results verify the analysis.