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Multi-stage amplifiers become logical choices for high-speed electronics and data conversion. The main difficulty in design is performing frequency compensation due to increasing high impedance nodes. In this work, a four-stage CMOS amplifier is frequency compensated using double differential feedbacks paths. Only two small compensation capacitors, less than 1 pF are used to form four Miller loops and driving a 500 pF load capacitor. The transfer function is calculated and simplified to estimate circuit dynamics while HSPICE and TSMC 0.18 µm CMOS technology are used to simulate the proposed four-stage amplifier. According to simulations and mathematical description, the proposed structure shows 147 dB, 6.3 MHz and 85° as DC gain, GBW, and PM respectively while consumes 380 µW as power dissipation. According to the defined figure of merits, the proposed circuit shows performance excellency against the previous state of art designs. [ABSTRACT FROM AUTHOR]

Global radiative feedbacks have been found to vary in global climate model (GCM) simulations. Atmospheric GCMs (AGCMs) driven with historical patterns of sea surface temperatures (SSTs) and sea ice concentrations produce radiative feedbacks that trend toward more negative values, implying low climate sensitivity, over recent decades. Freely evolving coupled GCMs driven by increasing CO2 produce radiative feedbacks that trend toward more positive values, implying increasing climate sensitivity, in the future. While this time variation in feedbacks has been linked to evolving SST patterns, the role of particular regions has not been quantified. Here, a Green's function is derived from a suite of simulations within an AGCM (NCAR's CAM4), allowing an attribution of global feedback changes to surface warming in each region. The results highlight the radiative response to surface warming in ascent regions of the western tropical Pacific as the dominant control on global radiative feedback changes. Historical warming from the 1950s to 2000s preferentially occurred in the western Pacific, yielding a strong global outgoing radiative response at the top of the atmosphere (TOA) and thus a strongly negative global feedback. Long-term warming in coupled GCMs occurs preferentially in tropical descent regions and in high latitudes, where surface warming yields small global TOA radiation change but large global surface air temperature change, and thus a less-negative global feedback. These results illuminate the importance of determining mechanisms of warm pool warming for understanding how feedbacks have varied historically and will evolve in the future. [ABSTRACT FROM AUTHOR]

When is it appropriate, and consistent with ethical standards, for evaluators to modify reports in response to "requests" from clients to do so? Some evaluators may view any pressure to make any changes in their reports as an attack on their independence. While, clearly, it is not acceptable for evaluators to be asked to distort or misrepresent findings and conclusions, evaluators, no less than anyone else, should be open to feedback and not be above criticism. This article discusses under what circumstances and in what forms it may be appropriate, or not, for evaluators to be given feedback and requested to consider appropriate modifications to their reports. It then identifies steps that evaluators can take to minimize inappropriate "suggestions" for change, and what they can do in the event that this does happen. It also considers implications, and strategies, for internal as well as for external evaluators. [ABSTRACT FROM AUTHOR]

Using a photovoltaic (PV) emulator (PVE) simplifies the testing of the PV generation system. However, conventional controllers used for PVEs suffer from oscillating output voltage, requiring a high number of iterations, or being too complex to be implemented. This paper proposes a controller based on a resistance feedback control strategy that produces a stable and fast converging operating point for the PVE. The resistance feedback control strategy requires a new type of PV model, which is the current–resistance (I–R) PV model. This model is computed using a binary search method at a fast convergence rate. It is combined with a closed-loop buck converter using a proportional-integral controller to form the resistance feedback control strategy. The PVE's controller is implemented into dSPACE ds1104 hardware platform for experimental validation. The acquired experimental results show that the proposed PVE is able to follow the current–voltage characteristic of the PV module accurately. In addition, the PVE's efficiency is more than 90% under maximum power point operation. The transient response of the proposed PVE is similar to the PV panel during irradiance changes. [ABSTRACT FROM AUTHOR]

Background: Over-prescription and overuse of antibiotics are a major cause of concern in terms of healthcare and economic implications, as well as the emergence of microbial resistance worldwide. So far, efforts have been administered by many countries to regulate the consumption of antibiotics and overcome the rapid emergence of resistant bacteria. Assessment of the perspectives and behavior of physicians can play a major role in achieving this objective. Objectives: The objective of the present study was to assess the perspectives on the antibiotic prescription practice of physicians and evaluate their tendency to receive feedback on their performance in outpatient settings. Materials and methods: Attitudes and practices of 330 physicians on antibiotics prescription were evaluated using a validated questionnaire in 2014 in Mashhad, Iran. Results: 94% of physicians asserted that the prescription rate of antibiotics in Iran is higher than the global average. Physicians noted that "patients' tendency to prescribe antibiotics" is the primary reason of excessive prescription of antibiotics. Approximately, 84% of physicians were keen on receiving performance feedback. More than 71% of participants specified Short Message Service (SMS) notification as their preferred medium for receiving feedback. Conclusions: The dominant viewpoint of physicians was that the rate of antibiotics prescription in Iran is larger than the global average, which can lead to adverse economic and bacterial resistance consequences. Interventions such as 'performance feedback' have the potential to reduce antibiotics over-prescription. [ABSTRACT FROM AUTHOR]

This study examined the impact of microteaching experiences of preservice elementary teachers enrolled in a science teaching methods course. The microteaching lessons targeted the physical science concepts represented in the Texas Educational Agency's exam for early childhood through sixth grade teacher certification. The results of this study demonstrate that targeting preservice elementary teachers' specific areas of weakness in content through microteaching, feedback, and reflection can have a positive impact on the science subject teacher certification exam passing rate. Additionally, this type of intervention provides preservice teacher programs with another technique to improve science content understanding. [ABSTRACT FROM AUTHOR]

Intermediate-mass black holes (IMBHs; masses between |$100\rm{\, and \,}10^{6} \, \mathrm{M}_{\odot }$|⁠) historically comprise of an elusive population compared to stellar-mass and supermassive black holes (BHs). Recently, IMBHs have started to be observed at the centres of low-mass galaxies. We perform cosmological hydrodynamical simulations of |$(2 \, h^{-1} ~ {\rm Mpc})^3$| comoving boxes and investigate the growth and feedback of central IMBHs in dwarf galaxies (DGs). The earliest BHs appear at z ∼ 18–25 and grow thereafter by accreting gas and by merger with other BHs. We find that, starting from |$10^{2} \, \mathrm{M}_{\odot }$|⁠ , it is possible to build up IMBHs of a few |$\times 10^{5}\!-\!10^{6} \, \mathrm{M}_{\odot }$| by z = 5, when the BHs are seeded in haloes less massive than |$4 \times 10^{7} \, \mathrm{M}_{\odot }$|⁠. The BH accretion rates increase with time and reach |$\dot{M}_{\rm BH} = (0.2\!-\!0.8) \dot{M}_{\rm Edd}$| for the massive IMBHs by z = 4. The star formation rate density (SFRD) evolution of the DGs (stellar mass |$10^{5}\!-\!10^{8} \, \mathrm{M}_{\odot }$|⁠) has a peak plateau between z = 4 and 6. Star formation is quenched between z = 9 and 4. The SFRD is reduced by factors up to 3 when the BHs have grown to a few times |$10^5 \, \mathrm{M}_{\odot }$|⁠. Even in the presence of stronger supernova (SN)-driven mass ejection, the BHs continue to grow up to z ∼ 6, sustained by gas inflows driven by galaxy mergers and interactions in a cosmological environment. Our conclusions, based on numerical simulation results, support the scenario that early feedback from IMBHs in gas-rich DGs at z = 5–8 can potentially solve several anomalies in the DG mass range within the concordance Λ cold dark matter (ΛCDM) cosmological scenario (Silk 2017). Our results suggest that IMBHs at DG centres grow faster than their host galaxies in the early Universe, and the resulting BH feedback turns the DGs and the BHs dormant. [ABSTRACT FROM AUTHOR]

Baryonic feedback can significantly modify the spatial distribution of matter on small scales and create a bulk relative velocity between the dominant cold dark matter and the hot gas. We study the consequences of such bulk motions using two high-resolution hydrodynamic simulations, one with no feedback and one with very strong feedback. We find that relative velocities of order |$100\ {\rm km}\, {\rm s}^{-1}$| are produced in the strong feedback simulation, whereas it is much smaller when there is no feedback. Such relative motions induce dipole distortions to the gas, which we quantify by computing the dipole correlation function. We find halo coordinates and velocities are systematically changed in the direction of the relative velocity. Finally, we discuss potential to observe the relative velocity via large-scale structure, Sunyaev–Zel'dovich and line emission measurements. Given the non-linear nature of this effect, it should next be studied in simulations with different feedback implementations/strengths to determine the available model space. [ABSTRACT FROM AUTHOR]

We demonstrate the nonvolatile and volatile memory characteristics of a gate-all-around silicon nanowire feedback field-effect transistor (FBFET) with a nitride charge-storage layer analyzed by a commercial TCAD simulator. Our FBFET exhibits a threshold voltage window of 0.76 V with a programming/erasing time of ${1}~\mu \text{s}$ in the nonvolatile memory mode. We investigated the delay of read operations with accumulated charges in the intrinsic channel region in this memory mode. Moreover, the FBFET exhibits a sensing margin of 6.3 $\mu \text{A}$ and a read/write speed of 10 ns with an outstanding retention time, as well as nondestructive read characteristics in the volatile memory mode, allowing this device to operate without any refresh operation. In addition, we describe the operating principle of our device and demonstrate its potential as integrated memory for 3-D integrations. [ABSTRACT FROM AUTHOR]

Vertebrates respond to a diversity of stressors by rapidly elevating glucocorticoid (GC) levels. The changes in physiology and behavior triggered by this response can be crucial for surviving a variety of challenges. Yet the same process that is invaluable in coping with immediate threats can also impose substantial damage over time. In addition to the pathological effects of long-term exposure to stress hormones, even relatively brief elevations can impair the expression of a variety of behaviors and physiological processes central to fitness, including sexual behavior, parental behavior, and immune function. Therefore, the ability to rapidly and effectively terminate the short-term response to stress may be fundamental to surviving and reproducing in dynamic environments. Here we review the evidence that variation in the ability to terminate the stress response through negative feedback is an important component of stress coping capacity. We suggest that coping capacity may also be influenced by variation in the dynamic regulation of GCs—specifically, the ability to rapidly turn on and off the stress response. Most tests of the fitness effects of these traits to date have focused on organisms experiencing severe or prolonged stressors. Here we use data collected from a long-term study of tree swallows (Tachycineta bicolor) to test whether variation in negative feedback, or other measures of GC regulation, predict components of fitness in non-chronically stressed populations. We find relatively consistent, but generally weak relationships between different fitness components and the strength of negative feedback. Reproductive success was highest in individuals that both mounted a robust stress response and had strong negative feedback. We did not see consistent evidence of a relationship between negative feedback and adult or nestling survival: negative feedback was retained in the best supported models of nestling and adult survival, but in two of three survival-related analyses the intercept-only model received only slightly less support. Both negative feedback and stress-induced GC levels—but not baseline GCs—were individually repeatable. These measures of GC activity did not consistently covary across ages and life history stages, indicating that they are independently regulated. Overall, the patterns seen here are consistent with the predictions that negative feedback—and the dynamic regulation of GCs—are important components of stress coping capacity, but that the fitness benefits of having strong negative feedback during the reproductive period are likely to manifest primarily in individuals exposed to chronic or repeated stressors. [ABSTRACT FROM AUTHOR]

A general ${N}$ -by- ${N}$ coupling matrix that provides lossless uniform feedback to all laser array elements is demonstrated in the analysis of a passive coherent beam combining resonator. The resonator contains a spatial filter that sends rejected optical power from the combining optic back into the cavity. This recycling of otherwise unused power yields an increase in the average laser output power that scales with array size ${N}$ , even in the absence of passive phase effects that depend on the gain, intensity, and wavelength of the laser mode. To achieve this improvement, tailored path lengths and mirror reflectivities are required in the feedback arms, where the phase may be fixed, whereas in the gain arms, the path lengths vary randomly. [ABSTRACT FROM AUTHOR]

We consider transmission of discrete memoryless sources (DMSes) across discrete memoryless channels (DMCs) using variable-length lossy source-channel codes with feedback. The reliability function (optimum error exponent) is shown to be equal to $\max \{0, B(1-R(D)/C)\}$ , where $R(D)$ is the rate-distortion function of the source, $B$ is the maximum relative entropy between output distributions of the DMC, and $C$ is the Shannon capacity of the channel. We show that in this asymptotic regime, separate source-channel coding is, in fact, optimal. [ABSTRACT FROM AUTHOR]

Background: Rising rates of antimicrobial resistance are driven by overuse of antibiotics. Characterizing physician antibiotic prescribing variability can inform interventions to optimize antibiotic use.Objectives: To describe predictors of overall antibiotic prescribing as well as the inter-physician variability in antibiotic prescribing amongst family physicians.Methods: We conducted a 5 year cohort study of antibiotic prescribing rates by family physicians in Ontario, Canada using a repository of electronic medical records. Using multilevel logistic regression models fitted with random intercepts for physicians, we evaluated the association of patient-, physician- and clinic-level characteristics with antibiotic prescribing rates.Results: We included 3956921 physician-patient encounters, 322129 unique patients and 313 physicians from 41 family medicine clinics. Physicians prescribed a median of 54 (interdecile range 28-95) antibiotics per 1000 encounters. Female children aged 3-5 years were most likely to receive antibiotics compared with men ≥65 years (OR 4.01, 95% CI 3.89-4.13). The only significant physician-level predictor was median daily patient visits of ≥20 compared with <10 (OR 1.28, 95% CI 1.06-1.55). The median ORs without and with patient characteristics were 1.68 and 1.69, respectively. Thus, the odds of receiving an antibiotic varied by 1.7-fold for the same patient simply by virtue of encountering two different physicians.Conclusions: We observed substantial inter-physician variability in antibiotic prescribing that could not be explained by sociodemographic and clinical patient differences, suggesting that risk adjustment of antibiotic prescribing practices may not be required for audit and feedback of family physicians working in similar practice settings. [ABSTRACT FROM AUTHOR]

The strive to increase the energy yield of photovoltaic (PV) power systems has made PV module integrated dc–dc converters (dc-MICs) a reality of modern PV plants. These converters regulate their input voltage, and their dynamic behavior is heavily influenced by the non-linear characteristic of the PV module. The regulation of the PV module voltage and average inductor current by means of a linear cascaded controller is a popular control technique, simplifying the converter dynamics, and providing inherent current limiting; however, it is prone to instability depending on the interaction between the PV source and the interfacing converter, as well as the value of the controller parameters. These factors present a clear challenge for control design; moreover, the converter transient response undesirably depends on the PV module operating point. In order to solve these issues, while maintaining regulation of PV module voltage and average inductor current, this paper proposes to adopt a non-linear controller designed with the feedback linearization control (FLC) technique. The control laws are derived and implemented in a non-inverting buck–boost dc module integrated converter, as this is a favorite topology for the PV interfacing application. A digitally controlled converter prototype is built and used to obtain experimental results, where the FLC technique is compared with a linear cascaded control technique. The results confirm the superior performance of the presented FLC technique, which is robust and able to regulate the converter input voltage with fast and consistent dynamics, regardless of the PV module or load operating conditions. [ABSTRACT FROM AUTHOR]

This paper presents a new digital predistortion (DPD) technique for wide band applications. Digital predistortion is the most useful linearization technique to reduce power amplifier (PA) nonlinearity effects due to its high flexibility and low complexity. However, this technique requires high performances ADC to digitize the feedback signal whose bandwidth is equal to several times the original bandwidth due to spectral regrowth generated by the PA nonlinearity. This point represents one of the main bottlenecks for the deployment of the wideband LTE-A standard. The method proposed in this paper calculates the DPD coefficients iteratively using an ADC with a fixed bandwidth equal to the original bandwidth. The proposed method has been simulated and compared with other methods using Matlab. Simulation results show that the proposed method has almost the same performance as the other methods with an ACPR of − 60 dB. Moreover, it reduces considerably the constraints on the ADC and the power calculation resources. [ABSTRACT FROM AUTHOR]

Quenching of star-formation has been identified in many starburst and post-starburst galaxies, indicating burst-like star-formation histories (SFH) in the primordial Universe. Galaxies undergoing violent episodes of star-formation are expected to be rich in high energy cosmic rays (CRs). We have investigated the role of these CRs in such environments, particularly how they could contribute to this burst-like SFH via quenching and feedback. These high energy particles interact with the baryon and radiation fields of their host via hadronic processes to produce secondary leptons. The secondary particles then also interact with ambient radiation fields to generate X-rays through inverse-Compton scattering. In addition, they can thermalise directly with the semi-ionised medium via Coulomb processes. Heating at a rate of ∼10−25 erg cm−3 s−1 can be attained by Coulomb processes in a star-forming galaxy with one core-collapse SN event per decade, and this is sufficient to cause quenching of star-formation. At high-redshift, a substantial amount of CR secondary electron energy can be diverted into inverse-Compton X-ray emission. This yields an X-ray luminosity of above 1041 erg s−1 by redshift z = 7 which drives a further heating effect, operating over larger scales. This would be able to halt inflowing cold gas filaments, strangulating subsequent star-formation. We selected a sample of 16 starburst and post-starburst galaxies at 7 ≲ z ≲ 9 and determine the star-formation rates they could have sustained. We applied a model with CR injection, propagation and heating to calculate energy deposition rates in these 16 sources. Our calculations show that CR feedback cannot be neglected as it has the strength to suppress star-formation in these systems. We also show that their currently observed quiescence is consistent with the suffocation of cold inflows, probably by a combination of X-ray and CR heating. [ABSTRACT FROM AUTHOR]

In order to improve the students ' autonomous learning capacity and innovation ability, and to build a substantial knowledge foundation for students in basic course learning during the undergraduate stage, traditional assessment methods of teaching courses have been reformed tentatively. A new assessment method has been innovatively designed based on process assessment with positive feedback principle used in electronic circuit course. The new feedback scoring method is incubated from traditional process assessment method, but total score will be re-divided into two different parts. The small part is used as feedback score, then students'total scores are reevaluated according to their revision achievements based on the first experiment results in each teaching process. Exploiting advantages of the new method can emphasize teaching management, encourage second learning in a short term, promote self-study and innovation abilities of students. After two semester reform attempts, it is found that the experimental class can increase the average scores by 8% in comparison with the control class in corresponding semester, and demonstrate nearly 5% improvement in the follow-up courses. These results prove that the new method can effectively improve the students' overall learning quality. [ABSTRACT FROM AUTHOR]

Cardiac alternans is a heart rhythm instability that is associated with cardiac arrhythmias and may lead to sudden cardiac death. The onset of this instability, which is linked to period-doubling bifurcation and may be a route to chaos, is of particular interest. Mechano-electric feedback depicts the effects of tissue deformation on cardiac excitation. The main effect of mechano-electric feedback is delivered via the so-called stretch-activated ion channels and is caused by stretch-activated currents. Mechano-electric feedback, which is believed to have proarrhythmic and antiarrhythmic effects on cardiac electrophysiology, affects the action potential duration in a manner dependent on cycle length, but the mechanisms by which this occurs remain to be elucidated. In this study, a biophysically detailed electromechanical model of cardiac tissue is employed to show how a stretch-activated current can affect the action potential duration at cellular and tissue levels, illustrating its effects on the onset of alternans. Also, using a two-dimensional iterated map that incorporates stretch-activated current effects, we apply linear stability analysis to study the stability of the bifurcation. We show that alternans bifurcation can be prevented depending on the strength of the stretch-activated current. [ABSTRACT FROM AUTHOR]

Altered feedback perturbation studies have shown that speakers only partially compensate for shifts in vocal pitch, intensity, or spectral content. The partial compensation generally plateaus around 30%–40% of the non-shifted, baseline production and is proposed to reflect the integrated effect of altered (auditory) and non-altered (somatosensory) sensory feedback. The authors hypothesized that the same pattern should hold for changes in syllable duration with delayed auditory feedback. To test this, the authors calculated average syllable duration from 21 young adults who read a standard passage as auditory feedback was delayed by 0, 10, 50, 100, 200, 300, and 600 ms. Given the complex nature of speech errors elicited under delayed auditory feedback, the authors compared durational effects across two broad error categories: prolongations and repetitions. Average syllable duration increased non-linearly and reached a peak near 40% of baseline durations. Separated by error type, prolongations, and distortions made up 89% of perceived errors. Only 9% of perceived errors were identified as repetitions. Unlike prolongations, however, the duration of repeated tokens ranged from 74% to 110% of the target syllable and compensated fully for the delay. These results are consistent with the notion that increasing syllable duration compensates partially for delays in auditory feedback. The compensation pattern resembles that of responses to other forms of altered auditory feedback, which suggests that this may be a general attribute of low-level, sensorimotor compensation. The higher frequency of prolongation occurrences further suggests that these may be the primary means of compensation for delayed auditory feedback. Repetitions, on the other hand, likely reflect compensatory mechanisms of higher-level motor planning or sequencing processes. [ABSTRACT FROM AUTHOR]

Aim/Purpose: Students' perceptions about feedback in e-tests have not been studied using qualitative methods. Therefore, the objective of this study was to investigate the students' attitude towards electronic tests, focusing on the feedback. Background: Despite the advantages of electronic tests, it is one of the neglected technologies in the students' evaluation process. Based on the technology acceptance model, users' attitudes have a significant impact on the acceptance of each technology. There is a paucity of qualitative research regarding the examination of students' attitudes towards e-testing and instant feedback. Methodology: A pilot study was used to achieve the aims of the study. Using purposeful sampling, the attitudes of 40 students from the University of Birjand who participated in the electronic test were examined. Contribution: This study suggests interventions to improve the acceptance of electronic tests and reduce resistance to them. It provides insight into understanding the nature of immediate feedback in electronic tests, puts forth suggestions for the successful implementation of e-tests in the students' evaluation process, and further provides information on the relationship between immediate feedback and student test anxiety. [ABSTRACT FROM AUTHOR]

Recently, research and development of SiC power devices have been done, and SiC power devices have become commercially available. The SiC power devices are suitable for realizing to medium voltage applications. Since, the voltage rating of commercial power devices is limited to less than 1.2 kV, they should be connected in series to maintain a higher voltage rating. However parasitic parameters of these devices are not the same, and therefore the voltage sharing during turn‐off operations cannot be controlled. This article proposes a digital control for the voltage balancing of series connected SiC‐MOSFETs during turn‐off operations. In order to compensate the voltage unbalance conditions, this article presents a time‐adjustment gate‐drive circuit using a digital delay line; experimental results for the feedback control using a buck chopper circuit are also presented. [ABSTRACT FROM AUTHOR]

Abstract Traversing rough terrains is one of the domains where multi-legged walking robots benefit from their relatively more complex kinematics in comparison to wheeled robots. The complexity of walking robots is usually related not only to mechanical parts but also to servomotors and the necessary electronics to efficiently control such a robotic system. Therefore, large, middle, but even small walking robots capable of traversing rough terrains can be very costly because of all the required equipment. On the other hand, using intelligent servomotors with the position control and feedback, affordable hexapod walking robots are becoming increasingly available. However, additional sensors may still be needed to stabilize the robot motion on rough terrains, e.g., inclinometers or inertial measurement units, force or tactile sensors to detect the ground contact point of the leg foot-tip. In this work, we present a minimalistic approach for adaptive locomotion control using only the servomotors position feedback. Adaptive fine-tuning of the proposed controller is supported by a dynamic model of the robot leg accompanied by the model of the internal servomotor controller. The models enable timely detection of the leg contact point with the ground and reduce developed stress and torques applied to the robot construction and servomotors without any additional sensor feedback. The presented results support that the proposed approach reliably detects the ground contact point, and thus enable traversing rough terrains with small, affordable hexapod walking robot. Highlights • Adaptive locomotion control for affordable multi-legged walking robots with position feedback only. • Model of the motion dynamic in the swing-down phase. • Experimental evaluation of locomotion control in crawling rough terrains. [ABSTRACT FROM AUTHOR]

One of the key challenges in Internet of Things (IoT) networks is to connect many different types of autonomous devices while reducing their individual power consumption. This problem is exacerbated by two main factors: first, the fact that these devices operate in and give rise to a highly dynamic and unpredictable environment where existing solutions (e.g., water-filling algorithms) are no longer relevant; and second, the lack of sufficient information at the device end. To address these issues, we propose a regret-based formulation that accounts for arbitrary network dynamics: this allows us to derive an online power control scheme that is provably capable of adapting to such changes, while relying solely on strictly causal feedback. In so doing, we identify an important tradeoff between the amount of feedback available at the transmitter side and the resulting system performance: if the device has access to unbiased gradient observations, the algorithm's regret after $T$ stages is $\mathcal O(T^{-1/2})$ (up to logarithmic factors); on the other hand, if the device only has access to scalar, utility-based information, this decay rate drops to $\mathcal O(T^{-1/4})$. The above is validated by an extensive suite of numerical simulations in realistic channel conditions, which clearly exhibit the gains of the proposed online approach over traditional water-filling methods. [ABSTRACT FROM AUTHOR]

In this paper, a nonlinear controller is presented for regulating an emerging class of high power density, high power-conversion efficiency, and high reliability (H3) single-phase power converters featuring small buffering capacitors. The proposed controller combines the best features of input–output feedback linearization and an automatic-power-decoupling (APD) control strategy, and achieves enhanced dynamic performances as compared to existing solutions based on linear control techniques. By feedback linearization, the plant models of H3 single-phase converters are fully linearized and decoupled, and thus fast dynamics, large-signal asymptotic tracking, and global stability can be achieved with simple linear controllers. Additionally, the APD strategy further strengthens the robustness of the closed-loop system as active pulsating power buffering (of the instantaneous power difference between the ac-port and the dc-port of the converter) of basically any form can be achieved. With the proposed nonlinear controller, we are able to further exploit the potential and unlock several new features intrinsic in H3 single-phase converters, e.g., active voltage holdup function, allowing extended holdup time (comparable to existing products with large dc-link capacitors) with only a small energy storage. The general theory, design procedures, and practical considerations of the nonlinear controller are detailed. A 100-W hardware prototype is also built to demonstrate the advantages of the proposed solution. New opportunities of H3 single-phase power converters with the aid of the proposed nonlinear control are also suggested for future research. [ABSTRACT FROM AUTHOR]

This paper presents a calibration-free 12-bit 50-MS/s full-analog SAR analog-to-digital (A-to-D) converter (ADC) in 40-nm CMOS, which integrates the functions of comparator, SAR logic, and digital-to-analog converter (DAC) switches into multiple feedback zero-crossing detectors (FB-ZCDs). By eliminating all the digital circuits, the full-analog bit conversions operate with the asynchronous amplification-to-regeneration (A-to-R) operation that highly relaxes the requirements of the analog circuits and reference generator. This paper is implemented without any calibration, where the non-ideal effects (offset mismatch, insufficient residue, and noise) are mitigated and eliminated with the proposed techniques as follows. The offset mismatches among the FB-ZCDs are covered by the redundancies of the sub-radix DAC arrangement in the coarse ADC. The bottom-plate coupling compensators (BPCCs) are proposed to correct the consecutive SAR decision errors as quantizing the insufficient residue. The shared FB-ZCD with capacitor coupling decision (CCD) network is developed to obtain the identical offset in the fine ADC. Amplification extension (AE) technique is proposed to enhance the precision of the shared FB-ZCD by reconfiguring as a complementary inverter-based amplifier with the extended amplification period to enhance the output SNR. This paper occupies an active area of 0.01 mm2 and achieves the Nyquist-rate signal-to-noise-and-distortion ratio (SNDR), spurious-free dynamic range (SFDR), Walden figure-of-merit (FoMW), and Schreier FoM (FoMS) of 64.1, 75.6 dB, 5.3 fJ/conversion step, and 172.8 dB, respectively. [ABSTRACT FROM AUTHOR]

Theoretical models and empirical analyses have combined to suggest that, for some ranges of climate, alternative stable states in vegetation structure may be possible: positive feedbacks with fire may differentiate savanna from forest, while positive feedbacks with hydrological processes may differentiate grassland from savanna. However, existing models have largely failed to include spatially explicit fire spread, dispersal, and hydrological processes, and as such ignore key features of vegetation systems. In this paper, we incorporate spatial and stochastic effects to form a comprehensive and realistic description of the dynamics of vegetation growth. By using novel computational tools such as path-sampling, we investigate the effect of noise and spatial coupling on the stability and the dynamics of forest-savanna transitions. Spatial effects change model behaviors: We find that spatial interactions between savanna and grassland result in the eventual nucleation and propagation of one of the states to invade the other. Which state wins depends on parameter values, which in turn depend on environmental conditions. Meanwhile, transitions between savanna and forest occur much less frequently, because an event such as a period of fire suppression in savanna or a fire in forest must be larger to successfully invade a landscape; this results in transitions between savanna and forest that, although not strictly history dependent, look temporally similar to hysteresis because the time lags involved in transitions are so large. [ABSTRACT FROM AUTHOR]

A Pixel Circuit for light‐emitting display is presented. The circuit improves controllability of emission current by a feedback network composed of backgate of the drive transistor. The effect is adjusted by the capacitance ratio of the topgate insulator to the backgate insulator and superimposed when the networks are connected in series. [ABSTRACT FROM AUTHOR]

In this paper, an ultra-wideband (UWB) low noise amplifier (LNA) with improvement in noise figure (NF) and gain flatness using 0.18-um RF CMOS technology is presented. Two cross-coupled capacitors (CCC) and new gain flattening technique in a cascode common-gate structure are used for NF and gain flatness improvement, respectively. In addition, NF calculation of CCC cascode common-gate amplifier is presented considering the noise of cascode stage. The LNA operates from 3.1 GHz up to 10.6 GHz with no change in power consumption compared with conventional one. The proposed LNA achieves average S21 of 21 d B and S11 less than −10 dB in the entire bandwidth. Additionally, the minimum NF of 2.38 dB is achieved. Furthermore, the power consumption at 1.8 V supply voltage is 4.34 mW and the core layout size for proposed LNA using CCC with and without including new gain flattening techniques are 881 μ m × 1201 μ m and 680 μ m × 733 μ m , respectively. [ABSTRACT FROM AUTHOR]

This paper examines the Rayleigh fading multiple-input single-output interference channel with single-user decoding and limited channel state information (CSI) feedback. Its contribution is twofold. First, the achievable rate-region with imperfect CSI at the transmitters due to channel quantization errors is analyzed for the two-user case. An analytically tractable inner bound on that region is derived, which provides insights into the problem. Similarly to the case of perfect CSI at the transmitters, it can be shown that beamforming constitutes an optimal strategy for achieving the boundary points of the inner bound. Second, we present a novel CSI feedback scheme that reduces the cross-link CSI feedback overhead, and enhances throughput for any rate-limited feedback scheme. This feedback reduction is crucial when control channels for sharing information between transmitters and unintended receivers are rate limited. A distinguishing feature of the proposed scheme is that feedback is taken into account already at the channel estimation stage. While maintaining a high array gain in the direct channel towards the intended user, the scheme induces an effective low-dimensional cross-link channel, which can be quantized more accurately than the full-dimensional channel. This eventually leads to enhanced performance while maintaining a low CSI feedback overhead. Finally, the proposed feedback scheme is extended to the case of $N>2$ users and shown to provide a significant reduction in CSI feedback overhead in a practically oriented setting. [ABSTRACT FROM AUTHOR]

This paper proposes a single-inductor dual-output (SIDO) DC-DC boost converter with Near-threshold Start-up voltage which adopts ordered-power-distributive-control (OPDC) method. A load-dependent feedback loop control is proposed to effectively suppress cross-regulation between the outputs, which is simple and flexible. Meanwhile, a two-step start-up scheme which makes the start-up circuit simpler has been put forward. It makes sure that the SIDO converter can adjust and complete near-threshold start-up depending on different load currents. This SIDO DC-DC converter has been fabricated in 0.18 μm CMOS process. The minimum starting voltage is 0.5 V, and the simulation results show that the cross-regulation suppression circuit successfully reduce the voltage cross-regulation ratios VCR1 and VCR2 to 0.2 mV/mA and 0.11 mV/mA, respectively. In normal operation, both of the output voltages and its corresponding maximum output currents are 1.2 V/40 mA and 1.8 V/40 mA. A maximum conversion efficiency of 91% can be achieved. [ABSTRACT FROM AUTHOR]

The LC resonance between the line inductor and the dc-link film capacitor is an important concern in the reduced dc-link capacitance interior permanent magnet synchronous motor drive system. In this paper, an active damping method based on the virtual damping resistor is applied to suppress the LC resonance and improve the drive system stability. The performance of the damping resistor is analyzed in a systematic level, and possible configurations have been analyzed to obtain the optimal solution, which is proved to be the inductor current feedback (ICF) damping method. In order to realize the equivalent damping effect, the dc-link voltage feedback is applied to emulate the ICF-based active damping method by a step-by-step approach. Meanwhile, the grid voltage distortion will stimulate additional harmonics of the grid current in the reduced dc-link capacitance motor drives. Hence a feedforward compensation method is applied to suppress the grid current distortion arising from the distorted grid voltage, which has not been investigated in the previous related researches. Harmonics of the grid current are reduced and requirements of EN61000-3-2 can be satisfied by applying the proposed method. Experiments on a compressor drive platform equipped with the reduced dc-link capacitance are performed to verify the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

The efficiency and output power of a high- $Q$ Class-E power amplifier (PA) are very sensitive to the values of the circuit components. Any mismatch between the nominal Class-E frequency and the input clock frequency could result in considerable degradation in the efficiency and much change in the output power. In this paper, we present a new self-oscillating Class-E PA, or so-called Class-E power oscillator (PO), whose feedback network is mainly constructed of a low- $Q$ RC circuit. As a result, the phase response of the feedback network is almost flat around the operating frequency, and if the nominal Class-E frequency of the load network changes due to variations in the component values, the phase shift in the feedback network does not change considerably, and therefore, the Class-E operation of the circuit is substantially maintained. We also present a complete design procedure for the proposed Class-E PO. We have built and tested a sample Class-E PO based on the proposed circuit. At $V_{DD}= {\text{4.5}}\,{\text{V}}$ , the measured oscillation frequency, output power, and efficiency of the circuit are 800 kHz, 0.96 W, and 89%, respectively. Simulation and measurement results confirmed that the efficiency and output power of the proposed Class-E PO have small sensitivities to the variations in the component values; therefore, we call the proposed circuit a self-tuned Class-E PO. [ABSTRACT FROM AUTHOR]

An LLC resonant converter would have light-load voltage regulation problems due to the effect of parasitic capacitances in a high-frequency range. In this paper, an energy feedback control method is proposed to improve the light-load regulation capacity by using synchronous rectifiers (SRs). The SR bridges are controlled ahead of the primary inverter bridges to deliver the energy from load to source, reducing the output voltage independent of the load. Then the desired voltage can be achieved even in no-load conditions by regulating the operation time of the energy feedback mode. The gain, voltage ripple, and efficiency performances of the proposed control method are discussed based on the precise analysis and an accurate model of the converter. Moreover, the light-load operations of the LLC resonant converter are analyzed deriving the critical load condition. Finally, the proposed control method is verified by the experiments of a 12 V/8 A LLC resonant converter prototype. [ABSTRACT FROM AUTHOR]

In recent years, many students in higher education have begun to learn programming languages. In doing so they will complete a variety of programming tasks of varying degrees of complexity. The students need to get consistent and personalized feedback to develop their programming skills. Human markers can provide personalized feedback using traditional manual approaches to assessment, but they may provide inconsistent feedback (especially for long programming solutions) since marking the programming solutions of multiple students can represent a significant workload for them. While full‐automated assessment systems are the best to provide consistent feedback, they may not provide sufficiently personalized feedback for novice programmers. This study develops a novel semi‐automated assessment approach in order to improve efficiency of human marker in the marking process and increase consistency of feedback (for both short and long programming solutions). It advocates the reuse of human marker's comments for similar code snippets, defined as segmented marking in this study. New full and partial marking models are developed based on segmented marking and they are tested by expert markers. The findings show that the two models are similar in efficiency, but that a partial marking approach potentially offers an improved efficiency for longer programming solutions. Such a finding has significant potential to reduce time spent on marking throughout the sector, which would have significant impact on both resourcing and timeliness of feedback. [ABSTRACT FROM AUTHOR]

This paper presents a wideband frequency-translational resistive-feedback receiver (RX), operational from 0.1 to 2.2 GHz. Different blocker suppression techniques are proposed to improve both out-of-band (OOB) compression and weakly nonlinear distortion of the RX. The blockers are first rejected at the RX input using an $N$ -path filter. Then, a blocker current cancellation (BCC) technique is used to mitigate the effect of nonlinearity in the transimpedance amplifier. By introducing an auxiliary path in the RX, the OOB linearity of the RX is further improved by means of frequency-translational noise cancellation (FTNC) and split-BCC. The RX prototype fabricated in a 130-nm CMOS process achieves 2.6–3.2-dB noise figure (NF) and tolerates a 0-dBm blocker at a 50-MHz offset with an NF of 4.9 dB. At 40-MHz offset from the local oscillator (LO), the RX exhibits higher +23-dBm out-of-band input-referred inter modulation product of order 3 (OB-IIP3) without FTNC and higher +26 dBm OB-IIP3 with FTNC. [ABSTRACT FROM AUTHOR]

This paper presents how the team from the Technical University of Denmark (DTU) implemented and solved the second challenge of the Mohamed Bin Zayed International Robotics Challenge. The competition was imitating a disaster scene where a robotic platform had to operate autonomously in a partly known environment to localize and manipulate a valve on a panel. To solve the given problem, the robot needs to be able to perceive the environment reliably. This is often accomplished using vision based solutions, however these might not always be feasible. Thus we show how force feedback can successfully be used as an alternative way of perception. To accomplish this the team equipped a robot arm with a force torque sensor, allowing the robot to perceive its environment through direct contact. This approach resulted in a robust solution of the task, independent of several external factors, such as lighting, which might affect a more traditional approach. First the theory and thoughts behind the implementation is presented, followed by an evaluation of the results from physical experiments and the competition itself, ultimately resulting in a robust solution which performed without errors in the competition. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Correlation between the maximum driving efficiency and the minimum current was experimentally validated. • Extremum Seeking Control (ESC) technique was utilized to track optimum driving frequency using current feedback. • For output power control, preload control had a wider operating range compared to voltage amplitude control. Abstract Despite their great features, ultrasonic motors' (USM) driving schemes still suffer from suboptimum driving efficiencies and limited operating range. The driving efficiency and operation range are mainly functions of the vibration amplitude and the preload. Vibration amplitude is generally controlled by means of adjusting the driving frequency. Unfortunately, there exists a narrow frequency band where efficiency is maximized resulting in a limited output power range. Due to temperature rise, this frequency is continuously shifting which necessitates dynamic tracking of the optimum state. Fortunately, maximum driving efficiency was experimentally confirmed to have good correspondence with minimum current. Current feedback was thus utilized within an Extremum Seeking Control (ESC) loop to track maximum efficiency. Besides driving frequency control, voltage amplitude and preload can be controlled to realize the desired output power while maintaining maximum efficiency. Using ESC technique, the maximum efficiency was successfully located and tracked under different voltage amplitudes and preloads. The output power under optimum condition was found to have a wider control range with preload control than with voltage amplitude control. [ABSTRACT FROM AUTHOR]

A shallow-depth differential source coupled logic is proposed in this paper, targeting low-voltage high-speed applications. In this logic, the number of transistor stages decreases from supply voltage to ground. This feature offers performance advantage over DCVSL (Differential Cascode Voltage Switch Logic) and DSCL (Differential Static CMOS Logic) styles in a circuit block. Using 180 and 65-nm standard CMOS technologies, the proposed logic demonstrates an average speed-up of 30% over CVSL (Cascode Voltage Switch Logic) based structures in the low-voltage region due to fewer series stages between supply voltage and ground nodes with near EDP (Energy-Delay Product) to its DSCL counterpart. Simulation and post-layout simulation results of 8-bit carry chain generator show that the proposed logic is 31, 23 and 13% faster than the DCVSL, DSCL and MTCML (Multiple-Tailed CML) carry generator chain, respectively. Proposed logic also demonstrates 7% and 6% PDP (power-delay product) reduction than DCVSL and DSCL carry generator chain, respectively. [ABSTRACT FROM AUTHOR]

There is an unmet need for formal curricula to deliver practice feedback training to residents. We developed a curriculum to help residents receive and interpret individual practice feedback data and to engage them in quality improvement efforts. We created a framework based on resident attribution, effective metric selection, faculty coaching, peer and site comparisons, and resident-driven goals. The curriculum used electronic health record–generated resident-level data and disease-specific ambulatory didactics to help motivate quality improvement efforts. It was rolled out to 144 internal medicine residents practicing at 1 of 4 primary care clinic sites from July 2016 to June 2017. Resident attitudes and behaviors were tracked with presurveys and postsurveys, completed by 126 (88%) and 85 (59%) residents, respectively. Data log-ins and completion of educational activities were monitored. Group-level performance data were tracked using run charts. Survey results demonstrated significant improvements on a 5-point Likert scale in residents' self-reported ability to receive (from a mean of 2.0 to 3.3, P <.001) and to interpret and understand (mean of 2.4 to 3.2, P <.001) their practice performance data. There was also an increased likelihood they would report that their practice had seen improvements in patient care (13% versus 35%, P <.001). Run charts demonstrated no change in patient outcome metrics. A learner-centered longitudinal curriculum on ambulatory patient panels can help residents develop competency in receiving, interpreting, and effectively applying individualized practice performance data. [ABSTRACT FROM AUTHOR]

Although the acoustic feedback could be alleviated by the neutralization method with a feedback model, an active noise control system could still suffer from being unstable if the feedback path exhibits significant variations. In this letter, a modified Wiener controller is introduced to enhance the robust stability with a fixed feedback neutralization filter. The proposed controller is designed with frequency-weighted penalties, which are adjusted iteratively according to Nyquist stability criterion. Experiment results based on a ventilation duct system shows that the robust stability could be achieved with the proposed method while a relatively good performance could be maintained. [ABSTRACT FROM AUTHOR]

Abstract Interactive ambulatory assessment offers a new approach to facilitate self-regulated learning in daily routine. 78 students were randomly assigned to the intervention (IG) and control group (CG). While preparing for a written exam, all the participants answered questions related to their learning behavior presented daily via electronic diaries (Phase 1). While preparing for a second exam (Phase 2), the CG completed the same assessment as in Phase 1, whereas the smartphones of the IG were fitted with intervening features to facilitate metacognitive strategy use. The IG was provided with near real-time feedback concerning their learning strategy use and personalized learning questions. Moreover, the IG completed a technology-based tutorial involving cognitive strategies before the beginning of Phase 2. Multilevel analyses revealed that cognitive and metacognitive strategies, internal resources and effectively used study time were associated with subjective learning success. The interventions promoted metacognitive strategies, internal resource-management strategies and subjective learning success. Highlights • Smartphones were used to investigate self-regulated learning in daily routine. • Successful learning was characterized by an intensive use of learning strategies. • Effectively used learning time was associated with learning success. • Interactive Ambulatory Assessment fostered self-regulated learning in daily routine. • Feedback and learning questions supported metacognition. [ABSTRACT FROM AUTHOR]

Low Noise Amplifier (LNA) is the front end block in RF receiver that improves the performance of wideband receivers. These receivers need LNA with high linearity to protect its signals from out-of-band interferences. Linearization is a key factor in LNA that maintains linear operation in the presence of large distracting signals. Existing techniques in LNA design are optimum gate biasing, MGTR, body biasing, noise cancellation, feed forward, derivative superposition, and modified DS technique. The key challenge of RF LNA circuit is to attain high gain and better noise performance with low power consumption without affecting linearity of LNA. This paper presents several linearization methods used in CMOS LNA. These are (1) post distortion, (2) capacitive feedback, (3) resistive feedback, and (4) current reuse technique. We also propose a new method for LNA with resistive and capacitive feedback. In this paper, different LNA circuits and proposed LNA are simulated using 90 nm CMOS technology. Reuse of bias current and two stage coupling by single current source approach in the proposed current reuse LNA with resistive (R) and capacitive (C) feedback yields better gain of 15.2 dB, noise figure of 2.17 dB and power consumption of 7.1 mW with respect to other techniques. The outputs obtained are compared with other similar works. These results validate that the proposed LNA is practically feasible for wireless sensor network applications. [ABSTRACT FROM AUTHOR]

This paper is focused on the linearization of the radio frequency power amplifier of a professional digital handheld by means of an artificial neural network. The simplicity of the neural network that is used, together with the fact that a feedback path is unnecessary, makes this solution ideal to reduce both the cost of a handheld and its hardware complexity, while fully maintaining its performance. A compensation system is also needed to keep the linearization characteristics of the neural network stable against frequency, temperature, and voltage variations. The whole solution that comprises both the neural network and the compensation system has been implemented in the digital signal processor of a real handheld and afterward fully tested. It has proved to be satisfactory to meet the telecommunication standard requirements in all frequency, temperature, and voltage ranges under consideration while efficient to lower the computational cost of the handheld and to make its internal hardware simpler in comparison with other traditional linearization techniques. The results obtained demonstrate that a neural network can be used to linearize the power amplifiers that are used in transmitters of telecommunication equipment, leading to a significant reduction of both their hardware cost and complexity. [ABSTRACT FROM AUTHOR]

Currently, virtual synchronous generator (VSG) technology is proposed to be a solution to stability controlling of micro-source inverter. However, the deviation from phase locked loop (PLL) influences the reference frequency calculating which is important to the VSG control system. This paper focuses on the virtual inertia controller in the VSG control system, an enhanced controller is achieved for avoiding the effect of PLL on the VSG dynamics. For analysing dynamic characteristics of the enhanced VSG control system, the linearised small-signal model of VSG in isolated operation is well established, including electrical system, enhanced virtual inertia controller, voltage and current controller, virtual impedance, and droop controller. By small-signal stability analysis, the influence rules of the main parameters (load, line, virtual inertia and proportional-Integral gain) on VSG system impacts are provided, which helps identifying possible feedback signals for controller design to improve the system stability. Results obtained from time-domain small-signal model are compared with those from the electrical simulation to verify its accuracy. [ABSTRACT FROM AUTHOR]

A method to transmit power and to communicate data in the reverse direction over only one pair of inductive coils is described. The system self-regulates the delivered load voltage, with no monitoring of or explicit feedback from the power receiver. Up to 94 mW of power can be transmitted over distances as large as 4.2 cm using coils of 3 cm diameter. The received voltage is unaffected by changes in coil separation up to a certain limit and also by changes of up to 40 $\times $ in load current demand. A constant envelope frequency-shift keying (FSK) modulation is also described to transmit data in the reverse channel that exploits mode-selection properties of a free-running oscillator. This allows smooth, uninterrupted delivery of power while data is being transmitted. [ABSTRACT FROM AUTHOR]

Among a sample of counseling students, results from hierarchical regression and mediation analyses indicated that attachment anxiety led to an increase in use of cognitive distortions, contributing to increased difficulty with corrective feedback during clinical supervision. Findings implicate a need for awareness of attachment patterns among trainees and the possible utility of cognitively focused supervisory interventions. [ABSTRACT FROM AUTHOR]

• The proposed calibration scheme saves time for signal acquisition. • Only need to collect the output signal to complete the calibration of the device. • High calibration accuracy and controllable error by feedback signal. An air-coil sensor (ACS) is a type of induction magnetometer used to measure the variation of a magnetic field. Due to the limited bandwidth of the coil, its output signal is distorted, a phenomenon known as the transition process. To measure the magnetic field accurately, the relationship must be confirmed by calibration. However, conventional methods require a uniform magnetic field with various frequencies to ensure the induced electromotive force is controllable. The time taken to acquire the signal correlates with the number of test frequencies, and the equipment used to generate the uniform magnetic field must be tailored to the shape of the ACS under test. This paper proposes a time-domain feedback calibration method for ACS to avoid the above constraints. An algorithm is applied to relieve the dependence of the calibration file on the input signal, so that the calibration file will not be affected by the calculation error of the input signal nor be limited by the uniform magnetic field, and the accuracy of the calibration file can be evaluated by the feedback signal. The exponential current, which contains a variety of frequency components, is selected as the calibration signal to shorten the time of data collection. The equipment used to generate the calibration signal is simple, which is suitable for on-site calibration. The scheme can be used for rapid calibration of various air-core coils, and provides a better solution for realizing embedded self-test of ACS. [ABSTRACT FROM AUTHOR]

This paper reports the emergence of bi-stability in a third-order memristive Wien-bridge oscillator. By transforming the parallel RC feedback network into a series resistor and capacitor (RC) feedback network in the previous non-ideal voltage-controlled memristor emulator, an improved memristor emulator is proposed and its fingerprints are exhibited. And then through introducing the proposed emulator to replace the parallel resistor in the conventional Wien-bridge oscillator, an improved memristor-based third-order Wien-bridge oscillator is constructed. Based on its mathematical model, the initial condition-dependent dynamical behaviour is revealed by theoretical analyses and numerical simulations and further verified by hardware experiments, from which the emergence of bi-stability in the memristive oscillator is well demonstrated. [ABSTRACT FROM AUTHOR]

A robust controller is designed based on feedback linearization and sliding mode control to damp sub-synchronous control interaction (SSCI) in doubly fed induction generator (DFIG) wind power plants (WPPs) interfaced with the grid. A feedbacklinearized sliding mode controller (FLSMC) is developed for the rotor-side converter (RSC) through feedback linearization, design of the sliding mode controller, and parameter tuning with the use of particle swarm optimization. A series-compensated 100-MW DFIG WPP is adopted in simulation to evaluate the effectiveness of the designed FLSMC at different compensation degrees and wind speeds. The performance of the designed controller in damping SSCI is compared with proportional-integral controller and conventional sub-synchronous resonance damping controller. Besides the better damping capability, the proposed FLSMC enhances robustness of the system under parameter variations. [ABSTRACT FROM AUTHOR]

In the area of teaching translation, investigating the effectiveness of technological solutions in developing translation skills is both timely and in demand. As the first step, one can try to explore feedback generated by machines compared to humans. The purpose of this study was to examine the impact of electronic feedback provided by the designed translation software on the translation skills of Iranian EFL students compared to the feedback given by an expert human observer. To this end, 60 intermediate male and female students were selected as participants after the administration of Oxford Placement Test (OPT), followed by a translation skill test as pretest and posttest. The analysis of the pretest and posttest data revealed that after receiving the two types of feedback, both groups performed significantly better on posttest. Further analysis of the data, however, indicated that sustained electronic observer feedback was superior to human observer feedback in terms of developing translation skills. It can be discussed that taking advantage of an efficient electronic tool which enjoys the potential of providing some feedback would drive the focus away from the repetitive mistakes and frees up the time and focus on students' personal problems. The findings may have implications for translation education, training, and practice. [ABSTRACT FROM AUTHOR]