Miracle-dz/UniFAR-FTUs huggingface dataset:
A 20–25.5 GHz VCO using a new variable inductor for K band application

A novel transformer-type variable inductor is proposed to achieve a wide tuning range at frequencies as high as K band. The variable inductor is designed, and an intuitive model is built to analyze its performance by HFSS. A lot of mathematical analysis is done in detail. A VCO using the proposed variable inductor is designed with TSMC 0.13 μm CMOS technology for verification. The frequency tuning range of the VCO depends on the proposed variable inductor. The phase noise of the VCO depends on the quality of the LC tank (including the proposed variable inductor and varactors). So a specific AMOS varactor is implemented to improve its quality factor. The VCO is simulated at three typical TSMC fabrication corners (TT, FF, SS) to predict its measure results. The post simulation results shows that the VCO achieves a 20–25.5 GHz continuous tuning range. Its phase noise results at 1 MHz offset are −108.4 dBc/Hz and −100.5 dBc/Hz respectively at the tuning frequencies of 19.6 GHz and 25.5 GHz. The VCO draws only 3 to 6 mA from a 1.2 V power supply.
MATHEMATICAL ENGINEERING TECHNICAL REPORTS

This paper derives a new necessary and sufficient condition for the smoothness of stationary subdivision surface schemes. First, we give a new necessary and sufficient condition for C1-continuity of stationary subdivision. Tangent plane continuity is equivalent to the convergence of difference vectors. Thus, using “normal subdivision matrix” [1], we derives a necessary and sufficient condition of tangent plane continuity for stationary subdivision at extraordinary points (including degree 6). Moreover, we derive a necessary and sufficient condition for C1-continuity. Second, we introduce new concepts such as the “j+1”-st difference vectors and the “jth difference mesh”, and construct procedure for generating j-th difference mesh from j − 1-st difference mesh, and “j + 1-st difference vectors” from j-th difference vectors. Here, we assume Cj-continuity at extraordinary points (including degree 6). Moreover, we define T j+1-continuity for the subdivision surface as tangent plane continuity of the limit surface generated by j-th difference mesh. Then, we can derive a necessary and sufficient condition of T j+1-continuity using “j + 1-st normal subdivision matrix”. Next, we assume T k-continuity at extraordinary points (including degree 6). Then, we can derive a necessary and sufficient condition for Ck-continuity. In this paper, we assume affine invariance. However, we can remove this assumption. So, the necessary and sufficient condition of Ck-continuity at extraordinary points (including degree 6) given in this paper is valid in a very general framework. Moreover, the necessary and sufficient condition is valid for subdivision surfaces except extraordinary points (including 6). That is, we derive the necessary and sufficient condition of Ck-continuity for stationary subdivision schemes.
Discharge current reduction in plasma displays for high Xe gas composition

Plasma displays with high brightness require high Xe percentage in the gas composition. The increase in Xe percentage in Ne-Xe gas mixture increases the sustain voltage as well as the discharge current. High power consumption is one of the main drawbacks of plasma displays. The challenge is to limit the power consumption without affecting the brightness. In present investigation the different constituents of discharge current have been studied and a new driving waveform has been proposed for suppression of Xe ion current.
The Complete Semiconductor Transistor and Its Incomplete Forms

This paper describes the definition of the complete transistor. For semiconductor devices, the complete transistor is always bipolar, namely, its electrical characteristics contain both electron and hole currents controlled by their spatial charge distributions. Partially complete or incomplete transistors, via coined names or/and designed physical geometries, included the 1949 Shockley p/n junction transistor (later called Bipolar Junction Transistor, BJT), the 1952 Shockley unipolar ‘field-effect’ transistor (FET, later called the p/n Junction Gate FET or JGFET), as well as the field-effect transistors introduced by later investigators. Similarities between the surface-channel MOS-gate FET (MOSFET) and the volume-channel BJT are illustrated. The bipolar currents, identified by us in a recent nanometer FET with 2-MOS-gates on thin and nearly pure silicon base, led us to the recognition of the physical makeup and electrical current and charge compositions of a complete transistor and its extension to other three or more terminal signal processing devices, and also the importance of the terminal contacts.
Numerical predictions of the behaviour of plain concrete targets subjected to impact

One widely used model implemented in the hydrocode ANSYS Autodyn is the Riedel–Hiermaier–Thoma material model, which is used for the prediction of concrete behaviour under severe loading, such as blast and impact. In the Riedel–Hiermaier–Thoma model, parameters are adjusted to be a function of the compressive strength of specific concrete. This advantage enables occasional users (and those who cannot conduct experiments to determine all the required concrete parameters) to input only this parameter, while the rest is automatically calculated by default settings. This study is an attempt to calibrate (not modify) this model, with the least number of possible changes, to better predict the performance of concrete targets, particularly spalling and scabbing phenomena, impacted by hard projectiles. It is shown that the present calibration of the Riedel–Hiermaier–Thoma material model performed well when compared to the default settings currently available in the model.
Creation of the π angle standard for the flat angle measurements

Angle measurements are based mainly on multiangle prisms – polygons with autocollimators, rotary encoders fo high accuracy and circular scales as the standards of the flat angle. Traceability of angle measurements is based on the standard of the plane angle – prism (polygon) calibrated at an appropriate accuracy. Some metrological institutions have established their special test benches (comparators) equipped with circular scales or rotary encoders of high accuracy and polygons with autocollimators for angle calibration purposes. Nevertheless, the standard (etalon) of plane angle – polygon has many restrictions for the transfer of angle unit – radian (rad) and other units of angle. It depends on the number of angles formed by the flat sides of the polygon that is restricted by technological and metrological difficulties related to the production and accuracy determination of the polygon. A possibility to create the standard of the angle equal to π rad or half the circle or the full angle is proposed. It can be created by the circular scale with the rotation axis of very high accuracy and two precision reading instruments, usually, photoelectric microscopes (PM), placed on the opposite sides of the circular scale using the special alignment steps. A great variety of angle units and values can be measured and its traceability ensured by applying the third PM on the scale. Calibration of the circular scale itself and other scale or rotary encoder as well is possible using the proposed method with an implementation of π rad as the primary standard angle. The method proposed enables to assure a traceability of angle measurements at every laboratory having appropriate environment and reading instruments of appropriate accuracy together with a rotary table with the rotation axis of high accuracy – rotation trajectory (runout) being in the range of 0.05 μm. Short information about the multipurpose angle measurement test bench developed is presented.
Inverse percolation by removing straight rigid rods from square lattices

Numerical simulations and finite-size scaling analysis have been carried out to study the problem of inverse percolation by removing straight rigid rods from square lattices. The process starts with an initial configuration, where all lattice sites are occupied and, obviously, the opposite sides of the lattice are connected by nearest-neighbor occupied sites. Then, the system is diluted by randomly removing straight rigid rods of length k (k-mers) from the surface. The central idea of this paper is based on finding the maximum concentration of occupied sites (minimum concentration of holes) for which connectivity disappears. This particular value of concentration is called the inverse percolation threshold, and determines a well-defined geometrical phase transition in the system. The results, obtained for k ranging from 2 to 256, showed a nonmonotonic size k dependence for the critical concentration, which rapidly decreases for small particle sizes (1⩽k⩽3 ? >). Then, it grows for k = 4, 5 and 6, goes through a maximum at k = 7, and finally decreases again and asymptotically converges towards a definite value for large values of k. Percolating and non-percolating phases extend to infinity in the space of the parameter k and, consequently, the model presents percolation transition in all ranges of said value. This finding contrasts with the results obtained in literature for a complementary problem, where straight rigid k-mers are randomly and irreversibly deposited on a square lattice, and the percolation transition only exists for values of k ranging between 1 and approximately 1.2×104 ? >. The breaking of particle-hole symmetry, a distinctive characteristic of the k-mers statistics, is the source of this asymmetric behavior. Finally, the accurate determination of critical exponents reveals that the model belongs to the same universality class as random percolation regardless of the value of k considered.
A Unified Frequency-Domain Model for Automatic Generation Control Assessment Under Wind Power Uncertainty

High frequency uncertainty of wind power is highly stochastic and unpredictable. It can have considerable impacts on automatic generation control (AGC) for power systems. This paper proposes a novel frequency-domain model to evaluate AGC performances under wind power uncertainty in frequency domain. High frequency volatilities are accurately described by the frequency model of wide-sense stationary stochastic process. The newly introduced frequency tools enable the variations of power/energy units and network variables to be represented by the generalized transfer functions of the independent or joint stochastic processes of wind power fluctuations. The time-domain operation constraints and performance criteria of CPS1 and CPS2 are successfully transformed into frequency domain on basis of a theorem and its corollary related to the calculation of cross correlation functions proved in this paper. In general, this paper proposes a unified way of modeling volatility sources, system operations, and AGC performance assessments in frequency domain. Case studies on an isolated system and IEEE 118 interconnected system demonstrate the effectiveness and the conveniences of the proposed frequency domain model.
DNA damage and repair in white blood cells at occupational exposure

: The present work was aimed at finding appropriate biomarkers applicable in molecular epidemiological surveys of occupationally exposed individuals and/or population in order to prove low dose effects. Blood samples were taken from NPP workers, in the ‘strict regimen’ area (exposed group) and from the administration staff (control group). The spontaneous and induced (exposed to a challenge dose of 2,0 Gy gamma irradiation) DNA repair synthesis in leucocytes, the level of DNA damage by single cell gel-electrophoresis in lymphocytes and the concentration of malonedialdehyde in blood serum, were analyzed. A significant decrease of potentially lethal damage in leucocytes as well as reduction of DNA double strand breaks level in lymphocytes of persons with ‘mean annual dose’ lower or equal to 5 mSv/a was found, compared to the control group. A higher repair capacity corresponding to elevated protein synthesis after a challenging dose of 2,0 Gy gamma rays and a significant decrease in the level of oxidative stress in the blood plasma were established in persons from the same group. The present investigation showed that annual doses not higher than twice the natural radiation background exert positive effects on DNA damage and repair, increase cellular resistance and decrease oxidative stress.
Emphasis on switch selection and its switching loss comparison for on‐board electric vehicle charger

A DC/DC converter plays a vital role in on-board electric vehicle (EV) charger. Among the many converter topologies, the phase-shifted full-bridge DC/DC converter (PSFBDC) is widely used. For improved efficiency, PSFBDC is embedded with passive auxiliary networks resulting in several unique configurations for achieving soft-switching in entire load range. The architecture of the chosen DC/DC converter configuration should comply with the society of automotive engineers (SAE) standards. Although, the conduction loss of the converter can be minimised by choosing a proper topology configuration and proper switching of the configuration, the selection of appropriate for PSFBDC plays an important role in enhancing the overall efficiency. An optimistic method for the selection of switch configuration satisfying the reduced power loss and cost-effective aspects is presented. For demonstrating the proposed method, a 1 kW 100 kHz system with commercially available switches IRFP460, IXFN64N60P, and IPP65R045C7 is chosen and the obtained results are presented.
Microwave Sensors Based on Coplanar Waveguide Loaded with Split Ring Resonators: A Review

This article reviews the application of physical, chemical and biological sensing of materials via microwave sensors based on a coplanar waveguide (CPW) loaded with a split ring resonator (SRR). Many CPWs loaded with SRR structures from the literature are reviewed in this article. CPWs loaded with many shapes of resonators have been proposed, such as circular, square and rectangular-shaped SRRs and CSRRs based on a paired and an array, folded stepped impedance (SIR), square and circular electric – LC (ELC) SRRs, circular, square, rectangular and golden ratio spiral S-shaped SRRs, diamond-shaped tapered SRRs, horn-shaped SRRs and others. The working principle for each device is briefly described and compared. The strength of this article is to introduce the application of microwave sensors based on CPWs loaded with SRRs for measurement and characterization of physical, chemical and biological materials through electromagnetic interaction.
Indium phosphide based multiple quantum well lasers: Physics and applications.

Multiple quantum well lasers based on the III-V compound semiconductor indium phosphide were studied in this thesis. Systematic investigations were carried out on the effects of quantisation and strain on the temperature sensitivity of threshold current, modulation properties, external cavity operation and the 'gain lever' effect. Trends in the temperature sensitivity of threshold current for lasers of various lengths and quantum well numbers can be understood in terms of the nonlinear gain-current density relation. However, compared to bulk active region devices there was no significant improvement. It is unclear at present whether this is due to the temperature sensitivity of optical gain or Auger recombination. Relative intensity noise measurements were used to compare the modulation properties of lattice-matched and strained MQW lasers. This method gives an estimate of the differential gain and was used to study the properties of devices which were unsuitable for high speed applications. These measurements showed that gain saturation and carrier transport effects may be significant in certain laser structures. Band-filling effects due to the reduced volume and modified density of states were utilised in the demonstration of a grating external cavity laser operating across the 1.3 mum optical fibre window. This configuration results in single-mode operation across the gain spectrum of the laser. High output power was exhibited across a wide tuning range. The 'gain lever' effect uses the nonlinear gain-current density relation to enhance the amplitude modulation efficiency and the signal-to-noise-ratio. MQW and bulk devices of different length and split ratio were compared. It was seen experimentally and numerically that the nonlinearity causing this effect also increases the distortion. Finally, it is discussed that further modifications to laser properties may be seen in active regions incorporating quantum wires and boxes.
Task Analysis of Two Crew Operations in the Flight Deck: Investigating the Feasibility of Using Single Pilot

This paper describes a task analysis of two crew operations in the flight deck in Part 121 Operations from gate to gate on a cross country flight. In addition, several non-normal scenarios were analyzed. Literature and operations materials were combined to develop the task lists. A primary source for this study is “An Exploration of Function Analysis and Function Allocation in the Commercial Flight Domain” by McGuire, et. al. (1991). Once the tasks were identified, they were set to an actually flight time schedule. Each task was assigned to either the Pilot Flying (PF) or the Pilot Monitoring (PM) in today’s operations. Additionally, tasks were categorized as: discrete or continuous; heads up or heads down; simultaneous with other tasks or performed serially; and whether any tasks are redundant. Introduction
Accurate integrated position and orientation method for vehicles based on strapdown inertial navigation system /Doppler radar

In order to realize maneuver combat in the modern warfare, some special military vehicles require the ability of determining their position and orientation rapidly and accurately, and the position and orientation system should be highly autonomous and have strong anti-jamming capability. So a high-accuracy independent position and orientation method for vehicles that utilizes strapdown inertial navigation system/Doppler radar is presented in this article. Laser gyroscopes in strapdown inertial navigation system and Doppler radar are adopted to develop a dead-reckoning system for vehicles. Subsequently, the attitude, velocity,and position-updating algorithms of dead-reckoning system are designed. The error sources of dead-reckoning system are analyzed to establish the system error model, including the attitude error equations of the mathematical platform, velocity error equations, and position error equations. The errors of strapdown inertial navigation system and deadreckoning system are selected as system states of the integrated position and orientation method. The difference between the attitude output of strapdown inertial navigation system and that of dead-reckoning system, and the difference between the position output of strapdown inertial navigation system and that of dead-reckoning system are chosen as the measurements of integrated position and orientation. Then, Kalman filter is adopted to design the filtering algorithm of integrated position and orientation. In the end, the integrated position and orientation method is validated by simulation experiment and vehicular experiment. The experimental results show that strapdown inertial navigation system/Doppler radar integration can realize accurate positioning and orientation for a long time, and the accuracy of attitude/position integration mode is significantly higher than that of velocity/position integration mode. Therefore, the former integration mode is more suitable for accurate position and orientation for vehicles.
A ΔΣ fractional-N frequency synthesizer for FM tuner using low noise filter and quantization noise suppression technique

A ΔΣ fractional-N frequency synthesizer fabricated in a 130 nm CMOS technology is presented for the application of an FM tuner. A low noise filter, occupying a small die area and decreasing the output noise, is integrated on a chip. A quantization noise suppression technique, using a reduced step size of the frequency divider, is also adopted. The proposed synthesizer needs no off-chip components and occupies an area of 0.7 mm2. The in-band phase noise (from 10 to 100 kHz) below −108 dBc/Hz and out-of-band phase noise of −122.9 dBc/Hz (at 1 MHz offset) are measured with a loop bandwidth of 200 kHz. The quantization noise suppression technique reduces the in-band and out-of band phase noise by 15 dB and 7 dB respectively. The integrated RMS phase error is no more than 0.48°. The proposed synthesizer consumes a total power of 7.4 mW and the frequency resolution is less than 1 Hz.
Simulation of inhomogeneous, non-stationary and non-Gaussian turbulent winds

Turbulence time series are needed for wind turbine load simulation. The multivariate Fourier simulation method often used for this purpose is extended for inhomogeneous and non-stationary processes of general probability distribution. This includes optional conditional simulation matching simulated series to field measurements at selected points. A probability model for the application of turbine wind loads is discussed, and finally the technique for non-stationary processes is illustrated by turbulence simulation during a front passage.
Optimal and efficient designs of Gaussian‐tailed non‐linearity in symmetric
 α
 ‐stable noise

This Letter proposes two methods for the Gaussian-tailed zero-memory non-linearity (GZMNL) design in symmetric α -stable noise. The optimal GZMNL is designed by maximising the efficacy via a derivative-free method. The efficient GZMNL is designed by polynomial fitting with the derived coefficients. Simulated results demonstrate that the GZMNL designs are nearly as optimal as the locally optimal detector, with an advantage of closed-form formulas.
A Novel Method to Develop High Fidelity Laser Sensor Simulation Model for Evaluation of Air to Ground Weapon Algorithms of Combat Aircraft

Successful release of any air to ground weapon from a combat aircraft is determined based on the positional parameters received from the sensors and the mission cues. Laser designated pod is one of the most sought weapon sensor, which gives the accurate data for Air to Ground weapon aiming. Laser designated pod being hardware intensive system, works with real world environment, it increases the development and integration effort towards finalising the weapon aiming algorithms and also pilot vehicle interface requirements. A novel method using mathematical models and the atmospheric error models is proposed to develop a high fidelity laser designated pod simulation model for functional and performance evaluation of weapon algorithms. The factors affecting the weapon trajectory computations are also considered in the sensor model outputs. The sensor model is integrated in the high fidelity flight simulator, which consists of both aircraft and Real world systems either as actual or simulated for close loop pilot evaluation. The behaviour of the sensor model is cross validated and fine-tuned with the actual sensor output and confirmed that the developed laser designated pod sensor simulation model meets all the requirement to test the air to ground weapons in the flight simulator.