nils-herrmann/clean_scirepeval huggingface dataset:
Numerical simulation study on electron mobility of independent DG MOSFETs

Numerical simulation study on electron mobility in independent DG MOSFETs with back gate biased in accumulation, flatband and inversion operation regions is presented in this paper. A numerical simulation program of the electron transport in the independent DG MOSFETs, which includes both phonon and surface roughness scattering mechanisms, is developed. From it, the dependence characteristics of the DG MOSFET electron mobility on the device operation conditions and the structure parameters are discussed. It is shown that DG MOSFET exhibits higher mobility when back gate is biased in inversion region compared to simulation results when back gate is in flat-band or accumulation regions. Mobility enhancement is observed in devices with thinner silicon film, when higher field is applied, which can be attributed to “volume inversion” in DG MOSFET.
Directional lasing and energy transfer in ZnO nanotree

The obliquely branched nanotree structures have been synthesized with the one-pot synthesis directly on the Zn substrate. The directional lasing spectroscopy of the nanometer branched ZnO crystallite arrays has been measured under high intensity femtosecond laser pulse excitation with femtosecond synchroscan streak camera as the detection system. The directional dependant ultrafast fluorescence emission gives clear evidence that there exists intelligent energy flow of ZnO nano-tree structures. Such processes open a way to fabricate the integrated optoelectronic apparatus.
A novel analytical method for maximum likelihood detection in MIMO multiplexing systems

This letter addresses the problem of symbol error probability (SEP) analysis for maximum likelihood (ML) detection in multiple-input multiple-output (MIMO) multiplexing systems. A new analytical method is presented based on the total probability theorem. The effects of imperfect channel estimation and power allocation scheme are investigated. The accuracy of the proposed method is demonstrated by Monte-Carlo simulations. It is shown that the analytical results match quite well with the simulation ones irrespective of the signal-to noise- ratio (SNR).
Data rate and dynamic range compression of medical images: Which one goes first?

Advances in the field of medical imaging have led to an immense increase in the volume of images being acquired. A fast growing application is to enable physicians to access image data remotely from any viewing device. This casts new challenges for data rate compression. Meanwhile medical images typically have High Dynamic Range (HDR), which needs to be transformed to Low Dynamic Range (LDR) through a so-called “windowing” operation in order for them to be viewed on standard displays to best visualize specific types of content such as tissues or bone structures. This leads to a basic question: Should data compression be performed before windowing or vice versa? Answering this question needs domain knowledge and also requires comparing HDR and LDR images in terms of objective measures, which has only recently become possible. In this paper, we compare the two alternative schemes by using a recently proposed structural fidelity measure. Our study suggests that data compression followed by windowing delivers better performance than the other alternative.
Implement of PWM Pulse Generator Based CPLD for Cascadedmultilevel Converter

Carrier phase-shifting sinusoidal pulse with modulation (SPWM) is one kind of commonly used algorithm for cascaded multilevel converter. The method of realization carrier phase-shifting PWM adopting complex programmable logical device (CPLD) is proposed in detail in this paper. This method simplifies the circuit design, enhances the system reliability and might guarantee the synchronicity of triggering power switches. At the end, the experimental results are given.
Wavelets for medical big data access improvement strategy over wireless network

Medical Big Data (MBD) is the most critical form of information. MBD over a colossal Wireless Network (WN) is a sophisticated area of concern. Every day WN is becoming more dense and complicated. The MBD can be saved to wireless network after applying suitable Wavelet Compression. The quality of MBD is the most important factor; which means efficient and reliable transmission. Wavelet Compression ensures the best image compression schemes such that the quality of data is not affected. MBD is in the form of medical reports, x-rays, CT scan image, audio video files. MBD over WN needs limited bandwidth utilization. Software Define Network (SDN) divides the network infrastructure into two planes. The Control Plane manages data flow and the Data Plane deals with the data. In-network coordinating cache via SDN support is a better way of network efficiency improvement. The cache size is very limited and can entertain only a limited number of requests. Our proposed system for MBD Cache (MBDC) is efficient to improvement the network performance using Wavelets. It is capable to work in Heterogeneous Network (Het Net) and Software Define Network (SDN) Architecture. By considering any shortest path like K-Means algorithm, the neighboring-content cache awareness reduces the latency time to fulfill the request from destination.
CDMA overlay situations for microcellular mobile communications

Direct sequence code division multiple access communications is a promising approach to cellular mobile communications, which operates in an environment characterized by multipath Rician fading. In this paper, the CDMA network is assumed to share common spectrum with a narrowband microwave user. Because of the presence of the narrowband waveform, an interference suppression filter at each CDMA receiver is employed to reject the narrowband interference. The problem of interference from adjacent cells is also considered. Average power control is assumed to combat the near/far problem, and multipath diversity, in conjunction with simple interleaved channel coding, is considered for improving the performance of the CDMA system.
Resource Allocation in User-Centric Wireless Networks

This paper presents a behavioral fairness-based resource allocation (RA) algorithm for uplink transmission of a multiuser orthogonal frequency division multiplexing system. The aim of fairness- based RA is to boost users' willingness to start and keep cooperating with each other and behave well to keep their trust and reputation high. An interesting notion of differentiated streams is also included in the proposed RA, which can fine-tune RA result to transfer excess bandwidth and power from real-time streams to non-real-time streams, i.e. increase useful throughput. In order to reduce the complexity of RA, a set of contiguous subchannels are grouped into a chunk to allocate resource chunk by chunk. The effects of users' contribution and the number of subchannels grouped in a chunk on the average throughput is analyzed and shown by numerical simulations.
Reduced- and No-Reference Image Quality Assessment

Recent years have witnessed dramatically increased interest and demand for accurate, easy-to-use, and practical image quality assessment (IQA) and video quality assessment (VQA) tools that can be used to evaluate, control, and improve the perceptual quality of multimedia content in a wide variety of practical multimedia signal acquisition, communication, and display systems. There is a vast and increasing proliferation of such content over both wireline and wireless networks. Think of the Internet: Youtube, Facebook, Google Video, Flickr and so on; networked high-definition television (HDTV), Internet Protocol TV (IPTV) and unicast home video-on-demand (Netflix and Hulu, for example); and an explosion of wireless video traffic that is expected to more than double every year over the next five years [1].
Objective Quality Assessment of Interpolated Natural Images

Image interpolation techniques that create high-resolution images from low-resolution (LR) images are widely used in real world applications, but how to evaluate the quality of interpolated images is not a well-resolved issue. Subjective assessment methods are useful and reliable, but are also slow and expensive. Here, we propose an objective method to assess the quality of an interpolated natural image using the available LR image as a reference. Our method adopts a natural scene statistics (NSS) framework, where image quality degradation is gauged by the deviation of its statistical features from the NSS models trained upon high-quality natural images. Two distortion measures are proposed, namely, interpolated natural image distortion (IND) and weighted IND. Validations by subjective tests show that the proposed approach performs statistically equivalent or sometimes better than an average human subject. Moreover, we demonstrate the potential application of the proposed method in parameter tuning of image interpolation algorithms.
Multi-operator retargeting based on perceptual structural similarity

We propose a new multi-operator retargeting algorithm by using three resizing operators of seam carving, scaling, and cropping iteratively. To determine which operator should be used at each iteration, we adopt structural similarity (SSIM) to evaluate the similarity between the original and retargeted images for the dynamic programming. Since the sizes of original and retargeted images are different, SIFT flow is used for dense correspondence between the original and retargeted images for similarity evaluation. Additionally, visual saliency is used to weight SSIM results based on the characteristics of the Human Visual System (HVS). Experimental results on a public image retargeting database show the promising performance of the proposed multi-operator retargeting algorithm.
A Quality-of-Experience Index for Streaming Video

With the rapid growth of streaming media applications, there has been a strong demand of quality-of-experience (QoE) measurement and QoE-driven video delivery technologies. Most existing methods rely on bitrate and global statistics of stalling events for QoE prediction. This is problematic for two reasons. First, using the same bitrate to encode different video content results in drastically different presentation quality. Second, the interactions between video presentation quality and playback stalling experiences are not accounted for. In this work, we first build a streaming video database and carry out a subjective user study to investigate the human responses to the combined effect of video compression, initial buffering, and stalling. We then propose a novel QoE prediction approach named Streaming QoE Index that accounts for the instantaneous quality degradation due to perceptual video presentation impairment, the playback stalling events, and the instantaneous interactions between them. Experimental results show that the proposed model is in close agreement with subjective opinions and significantly outperforms existing QoE models. The proposed model provides a highly effective and efficient meanings for QoE prediction in video streaming services.
Translation insensitive image similarity in complex wavelet domain

We propose a complex wavelet domain image similarity measure, which is simultaneously insensitive to luminance change, contrast change and spatial translation. The key idea is to make use of the fact that these image distortions lead to consistent magnitude and/or phase changes of local wavelet coefficients. Since small scaling and rotation of images can be locally approximated by translation, the proposed measure also shows robustness to spatial scaling and rotation when these geometric distortions are small relative to the size of the wavelet filters. Compared with previous methods, the proposed measure is computationally efficient, and can evaluate the similarity of two images without a precise registration process at the front end.
Quality prediction of asymmetrically distorted stereoscopic images from single views

Objective quality assessment of distorted stereoscopic images is a challenging problem. Existing studies suggest that simply averaging the quality of the left- and right-views well predicts the quality of symmetrically distorted stereoscopic images, but generates substantial prediction bias when applied to asymmetrically distorted stereoscopic images. In this study, we first carry out a subjective test, where we find that the prediction bias could lean towards opposite directions, largely depending on the distortion types. We then develop an information-content and divisive normalization based pooling scheme that improves upon SSIM in estimating the quality of single view images. Finally, we propose a binocular rivalry inspired model to predict the quality of stereoscopic images based on that of the single view images. Our results show that the proposed model, without explicitly identifying image distortion types, successfully eliminates the prediction bias, leading to significantly improved quality prediction of stereoscopic images.
Progressive switching median filter for the removal of impulse noise from highly corrupted images

A new median-based filter, progressive switching median (PSM) filter, is proposed to restore images corrupted by salt-pepper impulse noise. The algorithm is developed by the following two main points: 1) switching scheme-an impulse detection algorithm is used before filtering, thus only a proportion of all the pixels will be filtered; and 2) progressive methods-both the impulse detection and the noise filtering procedures are progressively applied through several iterations. Simulation results demonstrate that the proposed algorithm is better than traditional median-based filters and is particularly effective for the cases where the images are very highly corrupted.
SSIM-inspired two-pass rate control for High Efficiency Video Coding

We propose a perceptual two-pass rate control scheme for High Efficiency Video Coding (HEVC). The target bits are optimally allocated by hierarchically constructing a perceptual uniform space derived based on an SSIM-inspired divisive normalization mechanism for each group of pictures (GoP), each frame, and each coding unit (CU). The Lagrange multiplier λ, which controls the trade-off between perceptual distortion and bit rate, is adopted as the GoP level complexity measure. After the first pass compression, Laplacian based rate and perceptual distortion models are established to adaptively derive λ, and the target bits are dynamically allocated by maintaining an uniform Lagrange multiplier level through λ equalization. Within each GoP, rate control is further performed at frame and CU levels in the perceptually uniform space. Extensive simulations verify that, the proposed scheme can achieve high accuracy rate control and superior rate-SSIM performance.
Numerical calculation of refractivity and breakdown threshold of intense microwave propagation in atmosphere

The intense field of high power microwaves (HPM) causes the ionization of neutral particles in the atmosphere and a plasma comes into being. The ionization of neutral particles relates to the electric field intensity and atmospheric pressure. The paper calculates the refractive index in HPM, analyses the air breakdown threshold from the angle of the refractive index, and presents a relationship between working parameters, such as microwave frequency, gas pressure and pulse width, and the air breakdown threshold.
Image quality assessment: from error visibility to structural similarity

Objective methods for assessing perceptual image quality traditionally attempted to quantify the visibility of errors (differences) between a distorted image and a reference image using a variety of known properties of the human visual system. Under the assumption that human visual perception is highly adapted for extracting structural information from a scene, we introduce an alternative complementary framework for quality assessment based on the degradation of structural information. As a specific example of this concept, we develop a structural similarity index and demonstrate its promise through a set of intuitive examples, as well as comparison to both subjective ratings and state-of-the-art objective methods on a database of images compressed with JPEG and JPEG2000. A MATLAB implementation of the proposed algorithm is available online at http://www.cns.nyu.edu//spl sim/lcv/ssim/.
Video Quality Assessment by Incorporating a Motion Perception Model

Motion is one of the most important types of information contained in natural video, but direct use of motion information in the design of video quality assessment algorithms has not been deeply investigated. Here we propose to incorporate a recent motion perception model in an information theoretic framework. This allows us to estimate both the motion information content and the perceptual uncertainty in video signals. Improved video quality assessment algorithms are obtained by incorporating the model as spatiotemporal weighting factors, where the weight increases with the information content and decreases with the perceptual uncertainty. The proposed approach is validated using the Video Quality Experts Group Phase I test dataset.
Generic image similarity based on Kolmogorov complexity

Image similarity measurement is a fundamental and common issue in a broad range of problems in image processing, compression, communication, recognition and retrieval. Existing image similarity measures are limited to restricted application environments. The theory of Kolmogorov complexity and the related normalized information distance (NID) measure provide an attractive theoretic framework for generic image similarity that is applicable to any scenario. While this is appealing, the difficulty lies in the implementation due to the non-computable nature of Kolmogorov complexity. In this paper, we propose a practical framework to approximate NID, where the key is to find the shortest program within a set of potential transformations that convert one image to another and vice versa. As one of the initial attempts in this new and promising research direction, our preliminary experimental work demonstrates the wider applicability of the proposed approach than existing methods.
Two dimensionally spread OFCDM systems for 4G mobile communications

Future mobile communication systemsaim to provide extremely high speed data transmission, especially in downlink. The broadband orthogonal frequency and code division multiplexing (OFCDM) system with two-dimensional spreading (time and frequency domain spreading) is becoming a very promising technique for high speed wireless communications due to its advantages over OFDM. This paper presents the basic structure and main functions of the OFCDM system. A novel detection method for the OFCDM, called hybrid multicode interference (MCI) cancellation and minimum mean square error (MMSE) detection, is described. It has been shown in this paper that OFCDM is superior to OFDM.
Code Assignment for Downlink Transmission of Broadband OFCDM Systems

As a wireless access technique for future broadband mobile communications, orthogonal frequency and code division multiplexing (OFCDM) systems employ multi-code transmission to provide high speed mobile services. Since the multiple code channels are no longer orthogonal in the broadband wireless channel, multi-code interference (MCI) is caused. The variance of the MCI is dependent on which codes to be used. This paper investigates the code assignment in the multi-code OFCDM system, aiming to mitigate the MCI at the receiver. Since two-dimensional (2-D) spreading is employed in the OFCDM system, the code assignment is carried out in time and frequency domains, separately. In order to avoid large interference from the powerful code- multiplexed pilot channel, the time spreading code adjacent to the pilot code in the code tree is suggested not be used when the time domain spreading factor is large. The performance of the proposed code assignment scheme is analytically evaluated. It has been shown that the system performance can be improved significantly by the proposed scheme under various channel conditions, especially when a low to medium system load is assumed.
Performance analysis of FFH/MFSK receivers with self-normalization combining in the presence of multitone jamming

An analytical study is presented for the performance of fast frequency-hopping (FFH) self-normalized orthogonal M-ary frequency-shift-keyed (MFSK) noncoherent receivers in the presence of multitone jamming. The multiple equal-power jamming tones are assumed to correspond to some of the possible FFH/M-ary orthogonal signaling tones. It has been shown that a higher diversity order (the number of hops per symbol) improves significantly the worst case performance of the self-normalized receivers against multitone jamming and reduces the fading effect of jamming tones. There exists an optimum value of modulation order (M) that maximizes the worst case performance of the self-normalized MFSK receiver.
Mutual Coupling Calibration for Multiuser Massive MIMO Systems

Massive multiple-input multiple-output (MIMO) is a promising technique to greatly increase the spectral efficiency and may be adopted by the next generation mobile communication systems. Base stations (BSs) equipped with large-scale antennas can serve multiple users simultaneously by exploiting the downlink precoding in time division duplex (TDD) mode. However, channel state information (CSI) of uplink transmissions cannot be simply used for downlink precoding, because the gain mismatches of the transceiver radio frequency (RF) circuits disable the channel reciprocity. In this paper, we focus on antenna calibration for massive MIMO systems with maximal ratio transmit (MRT) precoding to solve the channel nonreciprocity problem. A new calibration method, called mutual coupling calibration, is proposed by using the effect of mutual coupling between adjacent antennas. By exploiting this method, the BS can perform the calibration without extra hardware circuit and users' involvement. We also build up the model of calibration error and derive the closed-form expressions of the ergodic sum-rates for evaluating the impact of calibration error on system performance. Simulation results verify the high calibration accuracy of the proposed method and show the significant improvement of system performance by performing antenna calibration.
Multiscale structural similarity for image quality assessment

The structural similarity image quality paradigm is based on the assumption that the human visual system is highly adapted for extracting structural information from the scene, and therefore a measure of structural similarity can provide a good approximation to perceived image quality. This paper proposes a multiscale structural similarity method, which supplies more flexibility than previous single-scale methods in incorporating the variations of viewing conditions. We develop an image synthesis method to calibrate the parameters that define the relative importance of different scales. Experimental comparisons demonstrate the effectiveness of the proposed method.