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In today's world of internet marketing product review plays a crucial role. Often E-Commerce companies are accused of manipulating with the data and it suffers from biasing. Biasing leads to wrong customer's view creation thereby prediction for a top rating product fails. This study shows how crowd annotation prevents this biasness and thereby design a smart contract which ultimately will help to eliminate the data manipulation. The smart contract is deployed and tested to see if data can be saved in the run time storage memory regions of the Ethereum blockchain, and the test results are positive. In future this will help to get the unbiased data and better machine learning results, which will ultimately be beneficial for the economy. [ABSTRACT FROM AUTHOR]

The effect of differential biasing of the divertor plates in a tokamak is analyzed using SOLPS‐ITER modeling with account of drifts and currents in the SOL. The ASDEX‐Upgrade like geometry and transport parameters adjusted for modeling of the semi‐detached nitrogen‐seeded plasma of shot #28903 are used in analysis. The additional voltage is applied to the outer divertor plate with respect to the grounded vacuum chamber and the inner divertor plate. When high negative voltage is applied, the high field side high density region almost disappears and the divertor plates become more symmetrical than without biasing, while in the case with positive voltage, the formation of the X‐point radiator begins, and both divertor plates become more detached. The results are qualitatively consistent with the experiments conducted on the JFT‐2 M and DIII‐D tokamaks. In addition, both signs of the applied voltage lead to a significant redistribution of the nitrogen within the SOL. Therefore, the possibility of edge plasma control by biasing is demonstrated. [ABSTRACT FROM AUTHOR]

A unique photonic technique has been suggested and explained for different types of waveform generation, the proposed technique employs double LiNbO3 Mach–Zehnder single drive cascading modulators for pulse shaping and responsive modulators for polarization. By ordering the incident light polarized states it can produce accordingly dual distinct Spectra on two components of orthogonal polarization. The desired waveform would be obtained by detecting the photocurrents from the photodetector. This paper describes the complete mathematical analysis of polarization dependent cascade Mach–Zehnder modulators to generate a variety of microwave forms. Comprehensive mathematical analyses including simulations have been presented, and therefore we have successfully developed as well as generated delta waveform, half-wave rectifier waveform, full-wave rectifier waveform, and square wave types waveform. At the end of the paper experimental analysis has been done for the proof of concept purpose while the experimental results of a variety of microwave waveforms are compared with theoretical ones. There are good agreements between theoretical results with experimental ones. [ABSTRACT FROM AUTHOR]

Due to the limit in computing power arising from the Von Neumann bottleneck, computational devices are being developed that mimic neuro-biological processing in the brain by correlating the device characteristics with the synaptic weight of neurons. This platform combines ionic liquid gating and electrowetting for programmable placement/connectivity of the ionic liquid. In this platform, both short-term potentiation (STP) and long-term potentiation (LTP) are realized via electrostatic and electrochemical doping of the amorphous indium gallium zinc oxide (aIGZO), respectively, and pulsed bias measurements are demonstrated for lower power considerations. While compatible with resistive elements, we demonstrate a platform based on transitive amorphous indium gallium zinc oxide (aIGZO) pixel elements. Using a lithium based ionic liquid, we demonstrate both potentiation (decrease in device resistance) and depression (increase in device resistance), and propose a 2D platform array that would enable a much higher pixel count via Active Matrix electrowetting.

BACKGROUND: The fronto-central slow-wave known as the contingent negative variation (CNV) is an electroencephalographic measure related to the ability of the motor system to extract spatial-temporal regularities to produce a motor response. AIM: This study aimed to investigate the levels of electrocortical activity prior to predictable and unpredictable stimuli in a motor control task, and the association between CNV and reaction time (RT). METHOD: Seventeen participants performed a task that consisted of removing the right index finger from the space bar as fast as possible after stimulus onset. All participants practiced under both a predictable (PC) and an unpredictable (UC) context. RESULTS: Results indicated that RT under the unpredictable context was slower than under the predictable context. However, CNV levels under predictable and unpredictable contexts did not differ. CONCLUSION: The certainty of stimulus appearance in the UC may have produced effects similar to those under the PC, resulting in similar CNV levels. However, the use of this mechanism under the UC was suboptimal to motor performance. [ABSTRACT FROM AUTHOR]

CMOS fixed- $g_{m}$ bias circuits are, as the name suggests, those that generate a bias current which keeps the transconductance of a MOS transistor equal to a constant (off-chip) conductance. Such circuits are useful in many analog and mixed-signal subsystems like filters and data-converters. This brief derives the textbook fixed- $g_{m}$ bias circuit from first principles, and shows these ideas can be used to generate alternative circuits. [ABSTRACT FROM AUTHOR]

A collaborative filtering-based recommendation system has been an integral part of e-commerce and e-servicing. To keep the recommendation systems reliable, authentic, and superior, the security of these systems is very crucial. Though the existing shilling attack detection methods in collaborative filtering are able to detect the standard attacks, in this paper, we prove that they fail to detect a new or unknown attack. We develop a new attack model, named Obscure attack, with unknown features and observed that it has been successful in biasing the overall top-N list of the target users as intended. The Obscure attack is able to push target items to the top-N list as well as remove the actual rated items from the list. Our proposed attack is more effective at a smaller number of k in top-k similar user as compared to other existing attacks. The effectivity of the proposed attack model is tested on the MovieLens dataset, where various classifiers like SVM, J48, random forest, and naïve Bayes are utilized. [ABSTRACT FROM AUTHOR]

We investigated the effect of a biasing tone close to 5, 15, or 30 Hz on the response to higher-frequency probe tones, behaviorally, and by measuring distortion-product otoacoustic emissions (DPOAEs). The amplitude of the biasing tone was adjusted for criterion suppression of cubic DPOAE elicited by probe tones presented between 0.7 and 8 kHz, or criterion loudness suppression of a train of tone-pip probes in the range 0.125-8 kHz. For DPOAEs, the biasing-tone level for criterion suppression increased with probe-tone frequency by 8-9 dB/octave, consistent with an apex-to-base gradient of biasing-tone-induced basilar membrane displacement, as we verified by computational simulation. In contrast, the biasing-tone level for criterion loudness suppression increased with probe frequency by only 1-3 dB/octave, reminiscent of previously published data on low-side suppression of auditory nerve responses to characteristic frequency tones. These slopes were independent of biasing-tone frequency, but the biasing-tone sensation level required for criterion suppression was ~ 10 dB lower for the two infrasound biasing tones than for the 30-Hz biasing tone. On average, biasing-tone sensation levels as low as 5 dB were sufficient to modulate the perception of higher frequency sounds. Our results are relevant for recent debates on perceptual effects of environmental noise with very low-frequency content and might offer insight into the mechanism underlying low-side suppression. [ABSTRACT FROM AUTHOR]

The benefits of thermionic emission from negatively biased electrodes for perpendicular electric field control in a magnetized plasma are examined through its combined effects on the sheath and on the plasma potential variation along magnetic field lines. By increasing the radial current flowing through the plasma thermionic emission is confirmed to improve control over the plasma potential at the sheath edge compared to the case of a cold electrode. Conversely, thermionic emission is shown to be responsible for an increase of the plasma potential drop along magnetic field lines in the quasi-neutral plasma. These results suggest that there exists a trade-off between electric field longitudinal uniformity and amplitude when using negatively biased emissive electrodes to control the perpendicular electric field in a magnetized plasma. [ABSTRACT FROM AUTHOR]

G protein-coupled receptors display multifunctional signaling, offering the potential for agonist structures to promote conformational selectivity for biased outputs. For β2-adrenergic receptors (β2AR), unbiased agonists stabilize conformation(s) that evoke coupling to Gαs (cyclic adenosine monophosphate [cAMP] production/human airway smooth muscle [HASM] cell relaxation) and β-arrestin engagement, the latter acting to quench Gαs signaling, contributing to receptor desensitization/tachyphylaxis. We screened a 40-million-compound scaffold ranking library, revealing unanticipated agonists with dihydroimidazolyl-butylcyclic urea scaffolds. The S-stereoisomer of compound C1 shows no detectable β-arrestin engagement/signaling by four methods. However, C1-S retained Gαs signaling--a divergence of the outputs favorable for treating asthma. Functional studies with two models confirmed the biasing: β2AR-mediated cAMP signaling underwent desensitization to the unbiased agonist albuterol but not to C1-S, and desensitization of HASM cell relaxation was observed with albuterol but not with C1-S. These HASM results indicate biologically pertinent biasing of C1-S, in the context of the relevant physiologic response, in the human cell type of interest. Thus, C1-S was apparently strongly biased away from β-arrestin, in contrast to albuterol and C5-S. C1-S structural modeling and simulations revealed binding differences compared with unbiased epinephrine at transmembrane (TM) segments 3,5,6,7 and ECL2. C1-S (R2 = cyclohexane) was repositioned in the pocket such that it lost a TM6 interaction and gained a TM7 interaction compared with the analogous unbiased C5-S (R2 = benzene group), which appears to contribute to C1-S biasing away from β-arrestin. Thus, an agnostic large chemical-space library identified agonists with receptor interactions that resulted in relevant signal splitting of β2AR actions favorable for treating obstructive lung disease. [ABSTRACT FROM AUTHOR]

End-to-end automatic speech recognition (E2E-ASR) prefers the common words during training rather than rare ones related to contextual information such as song names. Thus, recognizing contextual information correctly is a hurdle for E2E-ASR to reach the production-level. To overcome the limitations of E2E-ASR in recognizing contextual information, this work presents a post-processing followed by E2E-ASR in an algorithmic way, referred to as a word-matching algorithm with backward search (WMA-BS). At first, we allow E2E-ASR to roughly detect the position of target words that has similar pronunciation with desired contextual phrases. After that, given the hypothesis from E2E-ASR with the rough position of target words, WMA-BS estimates the correct target words and decides whether to replace the target words with the contextual phrase or not, according to their phonetic and literal similarity. Applying the proposed method to E2E-ASR achieved relative improvement up to 52.7% in word error rate across several harsh conditions. [ABSTRACT FROM AUTHOR]

Modern systems‐on‐chip use multiple current references to guarantee appropriate circuit biasing according to the required performance and power consumption. New reference topologies have emerged due to the necessity of ultra‐low‐power systems. Still, in the micro‐Ampere domain, the most common architectures are preferred in industry‐based applications, due to their reliability and accuracy. Motivated by the limited documentation and data associated with current references for SoCs, this work presents key observations in the design decisions, based on error contributions from the inherent elements of a reliable voltage‐to‐current reference architecture. Monte Carlo simulations show results for a 5 μA current reference, with inaccuracies at ±3σ of ±4% and ±1.3%, without and with trimming, respectively. Furthermore, two current references were fabricated using a 0.18 μm CMOS standard technology, in two different SoCs. Measurement results across voltage and temperature variations showed results for 50 μA ± 0.24% and 5 μA ± 0.8% current references without trimming. [ABSTRACT FROM AUTHOR]

In situ Transmission Electron Microscopy (TEM) techniques can potentially fill in gaps in the current understanding interfacial phenomena in complex oxides. Select multiferroic oxide materials, such as BiFeO(3) (BFO), exhibit ferroelectric and magnetic order, and the two order parameters are coupled through a quantum-mechanical exchange interaction. The magneto-electric coupling in BFO allows control of the ferroelectric and magnetic domain structures via applied electric fields. Because of these unique properties, BFO and other magneto-electric multiferroics constitute a promising class of materials for incorporation into devices such as high-density ferroelectric and magnetoresistive memories, spin valves, and magnetic field sensors. The magneto-electric coupling in BFO is mediated by volatile ferroelastically switched domains that make it difficult to incorporate this material into devices. To facilitate device integration, an understanding of the microstructural factors that affect ferroelastic relaxation and ferroelectric domain switching must be developed. In this article, a method of viewing ferroelectric (and ferroelastic) domain dynamics using in situ biasing in TEM is presented. The evolution of ferroelastically switched ferroelectric domains in BFO thin films during many switching cycles is investigated. Evidence of partial domain nucleation, propagation, and switching even at applied electric fields below the estimated coercive field is revealed. Our observations indicate that the occurrence of ferroelastic relaxation in switched domains and the stability of these domains is influenced the applied field as well as the BFO microstructure. These biasing experiments provide a real time view of the complex dynamics of domain switching and complement scanning probe techniques. Quantitative information about domain switching under bias in ferroelectric and multiferroic materials can be extracted from in situ TEM to provide a predictive tool for future device development.

Quantum digital-to-analog converters (DACs) based on programmable Josephson array [Programmable Josephson Voltage Standard (PJVS)] represent the most widely used quantum standard in ac voltage calibrations. The extension of PJVS frequency above the kilohertz range appears to be arduous; however, some enhancements are still practicable. In this work, we demonstrate the possibility to advantageously operate a conventional binary-divided PJVS array with a reduced number of bias lines. This feature is achieved by exploiting both the first and the second Shapiro steps along with nonconventional DAC codings. Two newly devised bias techniques are described in detail and preliminary experimental tests on waveform synthesis have been carried out and are presented here. [ABSTRACT FROM AUTHOR]

• A new window mixing (WM) estimator for the NPS, obtained as a convex combination of windowed periodograms, is presented. • Mathematical derivations show that WM estimator is unbiased and mean-square consistent. • The WM estimator shows better uncertainty characteristics than those of traditional and recently developed estimators. The statistical characteristics of several estimators of the noise power spectrum are analysed in this work. Averaged periodogram, Kim's large subimage and small subimage methods [1] together with windowed periodogram methods using rectangular and Hamming windows and a new window mixing method are studied to obtain their biasing and standard deviation. Sample means and sample standard deviations of the NPS calculations following the different methods are obtained using synthetic images that simulate noise in digital radiography images. In addition, biasing and variance characteristics of the windowed periodograms and the window mixing methods are derived theoretically. Biasing, characteristic of estimators based in periodograms, is eliminated by modifying the periodogram in such a way that it is obtained as the discrete Fourier transform of the unbiased sampled covariance of the signal. Simulations show that Kim's methods considerably improve the precision of the averaged periodogram, obtaining an important reduction in the sampled standard deviation. Also, the window mixing method, using a convex combination of windowed periodograms with rectangular and Hamming windows, improves the Kim's methods in terms of standard deviation and has similar biasing. Finally, it is shown that NPS estimators based in the windowed periodogram and in the window mixing methods are unbiased and mean-square consistent, provided that the support of the autocorrelation function of the system PSF is finite. [ABSTRACT FROM AUTHOR]

This brief presents the analysis of self-biased topologies to implement single-ended-input CMOS amplifiers. We depart from basic amplifying stages to construct the self-biased circuits. We propose an amplifier based on the common-source and cascode configurations with active load, in which all three transistors are self-biased. This translates into important advantages for the amplifier: less power consumption since biasing circuits are no needed, and a robust design because all transistors are guaranteed to be in the saturation region even with process, temperature, or supply variations. The only drawback of this topology is the low power-supply rejection. A prototype was designed in a 130-nm CMOS technology to have a gain of 40 dB in the frequency band between 100 kHz and 5 MHz. The measurements of the circuit demonstrated that the amplifier fulfilled the specifications at the nominal voltage (1.2 V) while consuming 13 $\mu \text{A}$. Furthermore, the circuit functions as amplifier for supply voltages as low as 400 mV and such high as 1.5 V, probing the flexibility of self-biased circuits. That flexibility can be explored in the future to design adaptive systems and to facilitate analog design automation. [ABSTRACT FROM AUTHOR]

This paper presents the radio frequency (RF) and linearity analysis of a dual dielectric (DD) reconfigurable FET (RFET) for a wide variety of analog applications. A RFET can either act as a MOSFET or a TFET based on the electric potential applied externally over source and drain regions. The impact of DD reduces ambipolar current to large extent. Hence, DD-RFET is a multi functional (MF) device that can be configured in such a way that superior analog properties can be obtained at reduced static power loss. We found that DD-RFET processes a threshold voltage (V t h)= 0.2 V, transconductance (g m) = 4 mS, and gain bandwidth product (GBP) = 0.4 THz in nMOSFET configuration, while V t h = 0.64 V and subthreshold swing (SS) = 34 mV/decade in nTFET configuration. Also, DD-RFET has a V t h = 0.14 V, g m = 0.3 mS, and GBP = 17 GHz in pMOSFET configuration, while V t h = 0.52 V and SS = 31 mV/decade in pTFET configuration. Hence, DD-RFET eases circuit design as this MF device helps to provide high performance and low power using multi threshold (MT) technology. Also, we found that MOSFET has better linearity at low bias voltage and as the gain increases with the supply, promotes noise and distortion in the output. However, TFET produces more stable results at higher bias voltage than MOSFET. Hence, there is a clear trade-off in active power and linearity exist in RFET designs. [ABSTRACT FROM AUTHOR]

In this experiment, the biasing effect on the control of turbulence in IR-T1 tokamak was investigated. The radial profile of the average density, the relative level of fluctuations and their power spectrum were obtained in the presence of biasing with two positive and negative polarities by using an array of Langmuir probe (Rake probe). Biasing was more effective in reducing the fluctuations at the edge of the plasma than in the more internal regions, but the spectral power of fluctuations in the inner regions decreased faster. Striking issue is that the positive bias has been more effective than negative bias in increasing of confinement. [ABSTRACT FROM AUTHOR]

Biasing is an essential feature of any electronic circuit. The traditional method of biasing involves applying a proper DC to fix the operating point and thereafter ensure its stability. In this paper, we have proposed a new concept of transistor biasing. Instead of a fixed quiescent point which is normally established by giving DC input to the transistor for the purpose of biasing, we have proposed an oscillating quiescent point by giving square wave biasing input, so that the quiescent point would be oscillating between the two ends of the load line. During the positive half cycle of the input signal the quiescent point would be at the bottom of the load line near the cutoff region, while during negative half cycle of the input signal, the quiescent point would be at the top of the load line near the saturation region, thereby giving full cycle operation for the signal excursion in the active region. The linear range of amplification is better exploited to give higher amplification with negligible distortion and high efficiency. [ABSTRACT FROM AUTHOR]

Highlights • A state-of-the-art chip-based in-situ optical-electrical test platform was fabricated by MEMS technology and designed to fit commercial in-situ heating holders. • The high stability, low drift-rate and long-lifetime of the in-situ chip under the illumination condition facilities atomic resolution S/TEM imaging and spectrum mapping of the sample. • An in situ photoconductivity experiment that was performed on a silicon carbide (SiC) nanowire demonstrates a good performance of the optical–electrical chip designed in this work. Abstract In situ transmission electron microscopy (TEM) technology has become one of the fastest growing areas in TEM research in recent years. This technique allows researchers to investigate the dynamic response of materials to external stimuli inside the microscope. Optoelectronic functional semiconducting materials play an irreplaceable role in several key fields such as clean energy, communications, and pollution disposal. The ability to observe the dynamic behavior of these materials under real working conditions using advanced TEM technologies would provide an in-depth understanding of their working mechanisms, enabling further improvement of their properties. In this work, we designed a microelectromechanical-system-chip-based system to illuminate a sample inside a transmission electron microscope. This system allows simultaneous in situ optical and electrical measurements, which are crucial for optoelectronic semiconductor characterization. [ABSTRACT FROM AUTHOR]