Miracle-dz/UniFAR-FTUs huggingface dataset:
On the short-channel theory for MOS transistor

An attempt is made to derive rigorous analysis for the short-channel MOS transistor on the basis of the 2-D Poisson's equation. The analysis is able to predict a correct dependence of the threshold voltage on channel length and drain voltage, avoids the need for the definition of an average depletion charge density, and gives more physical insight into the short-channel effects. >
A unified control scheme for a bi-directional AC-DC converter with high power quality

This paper presents the modeling, analysis, and design of a thyristor-based AC-DC converter, featuring bidirectional power flow and unity power factor at the AC side in both powering and regenerating modes. The unified controller regulates the voltage at the DC side and operates as a feedback control in the powering mode and a feedforward control in the regenerating mode. Systematic procedures for designing the power conversion stage and the controller are given.
Rejecting Disturbances to Flexible Structures using

The Proportional Kalman Filter (PKF) is for- mulated with integral action and generalized to the Propor- tional-Integral Kalman Filter (PIKF). The PIKF can be util- ized to improve the disturbance rejection property of the Kalman filter-based controller. Through extensive simula- tions, as applied to the lightly damped flexible structure of the 1992 ACC Benchmark, we show that the integral term of the PIKF allows effective estimation and rejection of arbi- trary disturbances. As a result, a single PIKF-based controller robiistly achieves full loop transfer recovery even when per- turbed by an unknown shaped disturbance marl Filter, 1992 ACC Benchmark.
Accelerated Development of Organizational Talent

This working paper explores the challenges of accelerated development of organizational talent. The meaning of the word "accelerated" is that such development takes place at a pace that is significantly higher than that of "traditional" development that allows an individual to learn the intricacies of the current job, observe incumbents in a higher level position (usually, one level up), practice elements of the boss' job when being delegated tasks, undergoing formal training, or benefiting from the knowledge accumulated by others and codified in the knowledge management systems. Accelerated development means, contrary to the usual, more traditional developmental path, bypassing traditionally expected career steps, stretched over a longer period of time learning opportunities, and/or age-related developmental progression. Accelerated development is a necessity for organizati of qualified individuals in the internal or external labor markets, and significant pressures from other organizations that are ready to "poach" talented executives and employees and offer them even higher levels of responsibility and remuneration. Organizations also respond with accelerated development initiatives to the individuals engaged in career entrepreneurship, i.e., those who make alternative career investments in order to enjoy quicker returns in terms of career growth and progression. This paper discusses the challenges of accelerated development programs, such as not only learning the competencies required in the new position, but also developing a new identity. The paper discusses the process of going through an accelerated development program and identifies its important elements: preentry experience, initial surprise of getting into the accelerated program's environment and learning to use it, engaging in identity exploration through examining past and present identities, staging identity experiments, and, finally, stepping out of the program into the real world.
Modeling and Control of Grid Side Converter in Wind Power Generation System Based on Synchronous VFDPC with PLL

Virtual flux oriented direct power control (VFDPC) is combined space vector modulation (SVM) with PI of DC-link voltage, active power and reactive power to control the grid side converter in wind power generation system in this paper. VFDPC has reached good performances with PLL (phase lock loop). First the mathematical models of grid side converter, LCL filter and phase lock loop are given. Then the control strategy of grid side converter-based wind power generation system is given in detail. Finally the simulation model is modeled consisting of power circuits, such as the grid side converter, LCL filter, transformer grid, and control parts, such as PI controllers of DC-link voltage, active power, reactive power, and SVM, and so on. The simulation results have verified that the control strategy is feasible to fit for control of gird currents, active power, reactive power and DC-link voltage in wind power generation system.
Wavelet decomposition of nonstationary heart rate variability

Power spectral density (PSD) of the long-term, 24-hour heart rate variability (LHRV) is widely used for risk stratification and noninvasive assessment of autonomic balance. The method can correctly identify the total power changes, but spectral estimates over narrow frequency ranges are inaccurate because of nonstationary character of the signal. An energy-frequency distribution (EFD) of LHRV based on a wavelet transform is proposed to overcome the nonstationarity problem and to obtain accurate spectral estimates over narrow frequency ranges. Holter ECGs from 54 patients with chronic autonomic imbalance and 27 normal subjects were used to derive the LHRV-signals. Mean EFD showed a characteristic peak that was shifted toward lower frequencies in patients compared to normal subjects. The slope of EFD at the high frequency ranges (>0.0329 Hz) was smaller in patients than in healthy subjects. EFD of 24-hour heart rate variability might be used as a more accurate tool for spectral estimation of the nonstationary frequency components than the power spectral integration over empirical frequency ranges.
A comparative study of maximum power point tracking methods for a photovoltaic-based water pumping system

In this paper the performance of the proposed fuzzy-based maximum power point tracking (MPPT) is investigated and compared with incremental conductance and constant voltage controller for a photovoltaic (PV) pumping system. A fuzzy logic controller with a mamdani inference engine using only nine rules is designed to track the optimum power point. An induction motor has been used to drive the centrifugal pump. The system performance is analysed for different weather conditions. A detailed comparative study presenting the merits and demerits of each technique is also presented in order to develop a relative relationship. Simulation results obtained indicate better performance of the fuzzy-based MPPT algorithm for the PV pumping system.
Performance assessment of storage policies of the Vaigai Reservoir using a simulation model

A comprehensive simulation model was used to assess the performance of the storage-based operating policies of the Vaigai Reservoir system, Tamil Nadu, India. The model first used historical inflow data, and then inflow data generated through an artificial neural network (ANN) model. The modelled releases were then compared with the actual ones. It was found that the existing storage-based policies were violated within the year but not on an annual basis, except in the recent past, when annual deficits occurred due to inadequate water availability from the upstream reservoir.
Aspect dependence of time-frequency signatures of a complex target extracted by impulse radar

We study the scattering interaction of a complex-shaped target with electromagnetic pulses of short duration transmitted by an impulse radar. The target is a metallized plastic scale model of an aircraft, in this case a B-52 bomber. The form-function, or radar cross-section (RCS), in the backscattering direction, filtered by the complete system made up of radar and digitizing signal analyzer, is determined from the measured data when the target, located in an anechoic chamber, is illuminated at each one of several different aspect angles. The directions of illumination are the head-on, broadside, and tail-on aspects together with a number of intermediate aspects. Also time-frequency signatures from the target are examined, and we notice in particular that they change in a well behaved manner with the aspect angles throughout the entire angular range from head-on to tail-on. Furthermore, the location of a few prominent features remains constant in wide angular intervals. Our examination of the aspect dependence of the time-frequency signatures suggests that the identification of complex-shaped targets can be based upon a small set of templates for each given target. Such sets of time-frequency signatures could then be used in conjunction with neural networks or other pattern recognizers to achieve the unambiguous classification of targets.
Development of a Localization System Based on VLC Technique for an Indoor Environment

In this paper, we develop an indoor localization device which embeds localization information into indoor light-emitting-diodes (LED) lighting systems. The key idea of our device is the use of the newly proposed "bit stuffing method". Through the use of stuff bits, our device is able to measure signal strengths even in transient states, which prohibits interference between lighting signals. The stuff bits also scatter the parts of the signal where the LED is turned on, thus provides quality indoor lighting. Additionally, for the indoor localization system based on RSSI and TDM to be practical, we propose methods for the control of LED lamps and compensation of received signals. The effectiveness of the proposed scheme is validated through experiments with a low-cost implementation including an indoor navigation task.
Restricted mobility or restricted competition? Fixed- mobile convergence and universal access in Brazil

The article explores the Brazilian regulation on fixed and mobile phone services and its impacts on efforts to address the deficit of ICT networks and services in low-income and low-density areas. We compare the three most significant cases in Brazil of fixed phone services deployment using GSM technology on a secondary basis and wireless local-loop technology associated with CDMA, investigating the effect of recent regulatory changes that facilitate access to spectrum by fixed phone enterprises. The analysis is based on the „microtelco‟ model proposed by Galperin and Bar (2006) and demonstrates that a favorable regulatory environment is an essential asset to foster new business models that are able to overcome persistent difficulties in universalizing fixed phone service both in attractive markets as well as in low-income and low-density areas.
Genetic amniocentesis: indications, outcome and complications retrospective cohort study during 13 years

Background: Amniocentesis (AC) is the most commonly used invasive prenatal test. The aim of this study was to determine which were the most common indications for AC, chromosomal abnormalities in relation to the age of the mother and complications as a result of AC. Methods: This is a retrospective thirteen-year cohort study including pregnant women who underwent AC in the period from 2008 to 2020. Patients were divided into two groups: below and above 35 years of age of mother at the time of AC. Results: During study period 2213 AC were performed, out of which 759 (34.29%) were in mother below, and 1454 (65.70%) above 35 years of age (p < 0.00001). The most common indication for AC in group above 35 years of age was advanced maternal age (93.9%), in group below 35 years of age was familial chromosomal diseases (29.91%). In all indications there is a statistically significant difference between the two age groups of pregnant women, all these indications are more prevalent in the group of pregnant women younger than 35 years (p < 0.00001). The most common chromosomal abnormalities in both groups was Down syndrome from numerical aberrations, and from structural inversion of chromosome 9. Short term complications were spontaneous abortion in 26 (1.17%), missed abortion in 4 (0.18%) and premature rupture of membranes in 4 (0.18%) cases. Conclusion: Advanced maternal age, demonstrated the strongest association with the uptake of AC, trisomy 21 was the most prevalent abnormal finding. Complications of AC are not significant compared to the general population of pregnant women.
Formal education of curriculum and instructional designers

In practice, few researchers and designers have strong conceptual understanding of the marriage between the design discipline and scientific research traditions. Rather, most have strong exposure to either research methodologies or instructional design methods, theories and/or practices. Within the Faculty of Behavioral Sciences, the University of Twente offers an education program in which design and research traditions are intertwined. This paper examines the ways in which research and design are brought together in Twente’s educational program, and offers critical reflections on how it might be better aligned with recent developments which place high value on design research and especially the societal relevance of (in this case, educational) research
On-line dead-time compensation method using disturbance observer

A new on-line dead-time compensation method for a permanent magnet (PM) synchronous motor drive is proposed. Using a simple disturbance observer without any additional circuit and off-line experimental measurement, disturbance voltages in the rotor reference dq frame caused by the dead time and nonideal switching characteristics of power devices are estimated in an on-line manner and fed to voltage references in order to compensate the dead-time effects. The proposed method is applied to a PM synchronous motor drive system and implemented by using software of a digital signal processor (DSP) TMS320C31. Simulations and experiments are carried out for this system and the results well demonstrate the effectiveness of the proposed method.
Diagnosis of stator, rotor and airgap eccentricity faults in three-phase induction motors based on the multiple reference frames theory

This paper describes the use of multiple reference frames for the diagnosis of stator, rotor, and eccentricity faults in line-fed and direct torque controlled (DTC) inverter-fed induction motors. The use of this new technique, which was proposed by the authors for the diagnosis of inter-turn short circuits, is extended for the detection and classification of different types of faults. Each fault causes a different disturbance or introduces different components in the motor supply currents. Based on the multiple reference frames theory, by choosing a proper reference frame, it is possible to transform each one of these current components to a d-q frame. In these d-q reference frames, those current harmonics will appear as constants, thus being easily measured, extracted or manipulated. Because each fault causes a different disturbance, the multiple reference frames technique can easily discriminate between different faults. Simulation and experimental results demonstrate the effectiveness of the proposed technique for the diagnosis of stator, rotor, and airgap eccentricity faults in three-phase induction motors. Moreover, due to the operating philosophy of the multiple reference frames technique, its integration into the control system of a DTC induction motor drive is a straightforward task and is briefly addressed at the end of the paper.
A system to monitor ocean wave fields

The directional characteristics of ocean surface wave fields are of great impact on the physics above, on and below the ocean surface. Numerous oceanographical investigations may not be conducted without considering the wave dynamics. For all kinds of human operations on the ocean knowledge of the actual wave field is crucial. Therefore the monitoring of the ocean wave fields is of urgent necessity. The presented system has been designed for the quick and complete detection of the two dimensional ocean wave energy. The sensor part of the presented system is provided from an ordinary commercially available navigational radar. Hardware was designed to A/D convert and store the raw data. The analytical part of the system calculates and displays the ocean wave energy. The system has already proven its usefulness in a series of scientific experiments as well as in practical offshore application. In this paper the quality of the system is discussed on a data base taken onboard the 'FORSCHUNGSPLATTFORM NORDSEE' during five months in the winter season 1990/91. <<ETX>>
Autonomous health monitoring of a stiffened composite plate

The paper presents a unified computer assisted automatic damage identification technique based on a damage index, associated with changes in the vibrational and wave propagation characteristics in damaged structures. An improved ultrasonic and vibration test setup consisting of distributed, high fidelity, intelligent, surface mounted sensor arrays is used to examine the change in the dynamical properties of realistic composite structural components with the appearance of damage. The sensors are assumed to provide both the low frequency global response (i.e., modal frequencies, mode shapes) of the structure to external loads and the (local) high frequency signals due to wave propagation effects in either passive or active mode of the ultrasonic array. Using the initial measurements performed on an undamaged structure as baseline, the damage indices are evaluated from the comparison of the frequency response of the monitored structure with an unknown damage. The technique is applied to identify impact damage in a woven stiffened composite plate that presents practical difficulties in transmitting waves across it due to scattering and other energy dissipation effects present in the material and the geometry of the structure. Moreover, a sensitivity analysis has been carried out in order to estimate a threshold value of the index below which no reliable information about the state of health of the structure can be achieved. The feasibility of developing a practical Intelligent Structural Health Monitoring (ISHM) System, based on the concept of "a structure requesting service when needed," is discussed.
Numerical Simulation of Air-water Bubbly Jet Issuing from a Square Nozzle by a Vortex in Cell Method

A water jet entrained with small air bubbles is simulated. The Vortex in Cell method for bubbly flow proposed by the authors in a prior study is used for the simulation. The method discretizes the vorticity field into vortex elements and computes the time evolution of the flow by tracing the convection of each vortex element using the Lagrangian approach. The bubbly jet issues vertically upward from a nozzle of square cross-section. The Reynolds number based on the water velocity is 5000. The bubble diameter is 0.2 mm, and the bubble volumetric flow rate ratio at the nozzle is 0.0025. The bubbles increase the water turbulence intensity around the jet centerline. This makes the water momentum diffusion in the lateral direction larger at the initial region of the jet. The bubble effect lessens with increasing axial distance from the nozzle. These simulated results are favorably compared with existing measurements, demonstrating the validity of the current simulation method for bubbly jet. In the developed region, the water velocity decay is relaxed and the half-width reduces. This is because the water is accelerated by the bubbles, which have higher axial velocity due to the buoyant force.
Identification of microRNAs Responding to Aluminium, Cadmium and Salt Stresses in Barley Roots

Plants are frequently exposed to various abiotic stresses, including aluminum, cadmium and salinity stress. Barley (Hordeum vulgare) displays wide genetic diversity in its tolerance to various abiotic stresses. In this study, small RNA and degradome libraries from the roots of a barley cultivar, Golden Promise, treated with aluminum, cadmium and salt or controls were constructed to understand the molecular mechanisms of microRNAs in regulating tolerance to these stresses. A total of 525 microRNAs including 198 known and 327 novel members were identified through high-throughput sequencing. Among these, 31 microRNAs in 17 families were responsive to these stresses, and Gene Ontology (GO) analysis revealed that their targeting genes were mostly highlighted as transcription factors. Furthermore, five (miR166a, miR166a-3p, miR167b-5p, miR172b-3p and miR390), four (MIR159a, miR160a, miR172b-5p and miR393) and three (miR156a, miR156d and miR171a-3p) microRNAs were specifically responsive to aluminum, cadmium and salt stress, respectively. Six miRNAs, i.e., miR156b, miR166a-5p, miR169a, miR171a-5p, miR394 and miR396e, were involved in the responses to the three stresses, with different expression patterns. A model of microRNAs responding to aluminum, cadmium and salt stresses was proposed, which may be helpful in comprehensively understanding the mechanisms of microRNAs in regulating stress tolerance in barley.
Listening to the people: politicians’ investment in monitoring public opinion and their beliefs about accountability

ABSTRACT Politicians’ understanding of public opinion constitutes a crucial factor in the representational relationship between them and the public. Therefore, politicians staying abreast of what citizens want and why they want it matters for democratic representation. In this study, we examine how intensely politicians monitor public opinion and why there is variation between politicians. Relying on survey evidence collected among Belgian MPs and U.S. local legislators, we show that politicians who more strongly feel the weight of voter scrutiny – who believe that voters are aware of what they do and will hold them accountable for it at the ballot box – interact more frequently with ordinary citizens, discuss public opinion more often with their fellow colleagues, and spend more time collecting public opinion information. The effect is potent, even if we control for politicians’ electoral vulnerability, their ambition and their role conception.
Understanding and Interpreting Urban Space (in)formation

This paper introduces a novel approach to understanding the complex information and logics of urban spaces by the non-professional public. A model for Interpretation of Qualities in Urban Space (aMIQUS) is proposed. The objectives are threefold: first, to form common, valid and applicable measures to assess features of space design; second, to indicate the developmental trait that considerably affect users' spatial experience which - taken as a consequence - derives from either sustainable/prudent or poor design decisions; and third, to generically recreate and visually represent urban spaces for communicative purposes. The model represents an identification method, not a problem-solving mechanism and is intended as a pragmatic instrument for recognizing crucial information, narrative, embedded in spatial scene. Model is followed by the initial idea to extend it in terms of an educational digital interface for the general public, participating in the process of urban decision-making. The paper concisely summarizes both theoretical and applicative efforts.