Miracle-dz/UniFAR-FTUs huggingface dataset:
Compact Dual-wideband Bandpass Filter Using Stub Loaded Zero-degree Feed Coupling Structure

A novel compact dual-wideband bandpass filter is proposed in this paper, by employing stub loaded ring-shape Uniform Impedance Resonator (UIR) and embed-inside T-shape resonator which contributes to reducing circuit size. Odd-even mode method can be used to analyze the resonance characteristic, since the structure is symmetrical. The stub-load UIR can produce two resonant frequencies of fodd1 and feven1, and the T-shape resonator can also introduce two resonant frequencies of fodd2 and feven2. By adjusting the position of odd-even mode resonant frequencies and the coupling degree between UIR and T-shape resonator, two wide passbands can be realized. In design, a pair of zero-degree feed coupling structure is utilized to generate two transmission zeroes at the lower and upper of the first passband, improving the frequency selectivity of the first. The 3 dB frequency bands range of the first passband and the second are 2.5 GHz–3.3 GHz and 5.1 GHz–6.2 GHz, and the fractional bandwidths are 29% and 19%, corresponding to center frequencies at 2.8 GHz, 5.8 GHz, respectively. Comparing with the previous works, the proposed dual-wideband bandpass filter has a compactness of 12 × 10.45 mm2 and has lower insertion loss of 0.1 dB and 0.12 dB, corresponding to the first and the second pass-band.
Optimized Periodic ΣΔ Bitstreams for DC Signal Generation Used in Dynamic Calibration Applications

Settling time is an important performance metric in digital-to-analog converters (DACs) that are used for dynamic calibration applications. To obtain an area efficient DAC design, periodic sequences are generated from sigma-delta modulators (<inline-formula> <tex-math notation="LaTeX">${\Sigma \Delta }$ </tex-math></inline-formula>Ms) using software, stores the sequence in memory and then passes it to a low-pass filter (LPF). In this brief, the sigma-delta (<inline-formula> <tex-math notation="LaTeX">${\Sigma \Delta }$ </tex-math></inline-formula>) bitstream generated in software will be optimized such that it yields a system that settles faster and is more area efficient. Two optimization routines are used, namely, serial method and random method algorithms. The random method is chosen to optimize the <inline-formula> <tex-math notation="LaTeX">${{\Sigma \Delta }}$ </tex-math></inline-formula> bitstreams for its computational simplicity. It will be shown, that using the random method routine provides at least 46% improvement in settling time performance of a 12-bit DAC, used in the paper as a design example. Moreover, it offers silicon area savings by at least 10% for resistor components and 35% for capacitor components. Similar results were obtained for 8 to 11 bits of resolution.
RF Rectifier with High Efficiency over a Wide Input Power Range Using a Voltage Controlled Switch in a ‘Handover’ Fashion

Wireless energy transfer gains from the option of receiving power from multiple sources with different power levels. This paper presents a rectifier that maintains good efficiency over a wide input power range at 2.45 GHz frequency using a MOSFET as the voltage controlled switch (VCS). The VCS performs a ‘handover’ function between a low threshold voltage diode and a high breakdown voltage diode in a seamless manner without interrupting power supply to the load. This topology has only so far produced good results at lower frequencies. An L-matching network is used to achieve impedance matching over the input power range at 2.45 GHz with the help of a blocking capacitor acting as a high pass filter. Simulated results show that the rectifier can maintain its RF to DC conversion efficiency above 50% from 3 to 23.8 dBm. A peak efficiency of 73% at 16.6 dBm is also recorded.
A Method to Implement Field-Induced Quantum-Confinement in MOSCAP-Based Line TFET Architectures

The underlying work presents a method to implement field-induced quantum-confinement (FIQC) in MOSCAP-based line TFET architectures. The potential well that originates in a conduction band (CB) due to the gate-bias results in bandgap widening, owing to the formation of quantized energy levels in a thin epi-layer. This, in turn, is expected to reduce the BTBT probability and adversely affect the turn-on voltage and $\mathbf{I}_{\mathbf{ON}}$ of the device. To mimic FIQC, we started by solving 1-D Schrödinger-Poisson solver in a MOSCAP structure and determined the lowest quantized energy level (E1), which then is used to modify the CB accordingly. Later, by incorporating the channel and drain regions, in addition to the MOSCAP, we calculated the drain current characteristics of an L-shaped TFET. We also showed the FIQC-led degradation on the device performance. Overall, a general framework, to incorporate FIQC in simulation studies of line TFETs are presented.
Exact Distributed Load Centrality Computation: Algorithms, Convergence, and Applications to Distance Vector Routing

Many optimization techniques for networking protocols take advantage of topological information to improve performance. Often, the topological information at the core of these techniques is a centrality metric such as the Betweenness Centrality (BC) index. BC is, in fact, a centrality metric with many well-known successful applications documented in the literature, from resource allocation to routing. To compute BC, however, each node must run a centralized algorithm and needs to have the global topological knowledge; such requirements limit the feasibility of optimization procedures based on BC. To overcome restrictions of this kind, we present a novel distributed algorithm that requires only local information to compute an alternative similar metric, called Load Centrality (LC). We present the new algorithm together with a proof of its convergence and the analysis of its time complexity. The proposed algorithm is general enough to be integrated with any distance vector (DV) routing protocol. In support of this claim, we provide an implementation on top of Babel, a real-world DV protocol. We use this implementation in an emulation framework to show how LC can be exploited to reduce Babel's convergence time upon node failure, without increasing control overhead. As a key step towards the adoption of centrality-based optimization for routing, we study how the algorithm can be incrementally introduced in a network running a DV routing protocol. We show that even when only a small fraction of nodes participate in the protocol, the algorithm accurately ranks nodes according to their centrality.
Joint Training ResCNN-based Voice Activity Detection with Speech Enhancement

Voice activity detection (VAD) is considered as a solved problem in noise-free condition, but it is still a challenging task in low signal-to-noise ratio (SNR) noisy conditions. Intuitively, reducing noise will improve the VAD. Therefore, in this study, we introduce a speech enhancement module to reduce noise. Specifically, a convolutional recurrent neural network (CRN) based encoder-decoder speech enhancement module is trained to reduce noise. Then the low-dimensional features code from its encoder together with the raw spectrum of noisy speech are feed into a deep residual convolutional neural network (ResCNN) based VAD module. The speech enhancement and VAD modules are connected and trained jointly. To balance the training speed of the two modules, an empirical dynamic gradient balance strategy is proposed. Experimental results show that the proposed joint-training method has obvious advantages in generalization ability.
Curating Explanations of Machine Learning Models for Business Stakeholders

Consumer-oriented products and services are increasingly incorporating artificial intelligence (AI) functionality or being influenced by machine learning in development; for example, AI is replacing rule-based systems in identifying anomalous behavior or selecting services for customers. With AI's increasing uses and impact on consumers, explainability becomes required by consumers, business stakeholders, and regulator. Many of relevant researchers have been geared toward End Users and Technical Audiences, especially in the space of feature importance and local explainability. However, Business Sponsors and Regulators have different requirements which can be further explored. We present a framework of potential requirements and concerns encompassing these stakeholders, including End Users, Technical Audiences, Business Sponsors and Regulators. Finally, we apply the framework to an example in the financial services space.
Pregnant and active – suitability of the Pregnancy Physical Activity Questionnaire for measuring the physical activity of pregnant women in Poland

Background. The issue of physical activity of pregnant women, including determining proper recommendations, has been a broadly discussed topic in international circles. Objectives. The aim of this paper is to present the suitability of the Pregnancy Physical Activity Questionnaire (PPAQ) for measuring the physical activity of pregnant women in Poland. Material and methods. The study included 162 questionnaires, which were filled in correctly by pregnant women (third trimester) who took part in childbirth classes organized by a childbirth school. As a research method, the PPAQ was chosen. The PPAQ allows pregnant women to self-assess their physical activity in the current trimester. The questions investigated time devoted to various types of activity related to household/caregiving, transportation, sports/exercise in their free time, occupational activity and inactivity. Based on the average weekly energy expenditure, each of these activities is classified by intensity: sedentary activity, light-intensity activity, moderate-intensity activity, vigorous-intensity activity. Results. While using the PPAQ in Poland, it is recommended to reduce the number of questions from 36 to 35, by removing question 18 (time of mowing lawn while on a riding mower). It is also advisable to convert American units of measurement into metric units, which are used in Poland. Conclusions. The Pregnancy Physical Activity Questionnaire in Poland may fill the gap in studies devoted to the physical activity of pregnant Polish women. With this questionnaire, it is possible to determine energy expenditure in terms of intensity and type of physical activity. It also serves as a reliable tool that can be used for international comparisons.
A Robust Unsupervised Method for the Single Channel Speech Separation

Single channel and blind speech separation (SCBSS) and enhancement are widely used in many real-time applications. The performance of the separation is crucial for these applications. However, such situations have complex features such as unknown numbers, complex forms of dialogue, severe noise pollution, and difficult to obtain information in advance. There are many challenges in single-channel and multi-person mixed speech separation based on unsupervised machine implementation. In this paper, a kind of unsupervised speech separation algorithm based on the combination of Convolutional Non-Negative Matrix Factorization (CNMF) and Joint Approximative Diagonalization of Eigenmatrix (JADE) (CNMF+JADE) is performed on the detected overlapped speech including the target speaker. The experimental results show that the method presented can effectively extract the target speaker in the speech mixtures generated by convolving TIMIT speech sources. Compared with the traditional supervised learning method, the proposed method can only use a small amount of training data to obtain the target speaker's speech without supervision in single-channel speech, which is more universal and robust. It provides a reference solution for speech extraction of target speakers in complex multi-speaker scenario.
A CMOS gm-C Low-Pass Filter for Direct Conversion Receivers with Tuning Capability

this work presents a third order Butterworth low-pass filter with a tunable capability that serves different wireless technologies such as Bluetooth, cdma-2000, wideband CDMA and IEEE 802.11 a/b/g/n. Hence, it is suitable for multi-mode direct conversion receivers. The filter is implemented using a gm-c topology. The gm-cell converts voltage to current using a triode region MOSFET device while a current-multiplier circuitry widens the tuning range and enhances linearity. By implementing a programmable capacitor array, the filter can operate over a cutoff frequency range of 200KHz to 40MHz. The filter was designed using 28nm CMOS process technology. It consumes 0.803mW to 1.04mW of power for minimum and maximum cutoff frequencies using a 1V supply voltage. It exhibits input referred noise (190-770)nV/√Hz at room temperature with acceptable linearity of 9.89dBm to 22.3dBm for minimum and maximum IIP3, respectively.
Radiation Pattern Reconfigurable Antenna Integrated With Electromagnetic Bandgap(EBG) Reflector

A pattern reconfigurable antenna having ability to switch beam in nine different directions is proposed in this paper. The proposed antenna consists of simple patch at the top and four complementary split ring resonators (CSRR) and eight PIN diodes integrated in the ground plane. By switching PIN diodes ON and OFF, the main beam can be switched to different directions in both E-plane and H plane. The antenna is designed for center frequency of 2.45 GHz. The proposed antenna is then integrated with $5\times 5$ Electromagnetic bandgap (EBG) structure which acts as a reflector to enhance the gain by 1.2dB and beam switching from 31 to 62 degrees in desired directions. The antenna covers the entire azimuth angles while 3dB beam width covers the elevation angles from 0 to more than 47 degrees. The antenna is having a compact size of $0.82\lambda\times 0.78\lambda$ while the EBG surface which acts as a reflector is having dimension of $179.4\times 179.4\text{mm}^{2}$ at 2.45 GHz. The proposed beam switchable antenna can be a prospective candidate for emerging 5G applications. The antenna is designed and simulated using CST Studio Suite.
Bandwidth-Enhanced Circularly Polarized Spiral Antenna With Compact Size

A compact circularly polarized (CP) spiral antenna with enhanced impedance and 3-dB axial ratio (AR) bandwidths that is fed by a tapered coax balun is presented. The antenna is composed of a two-arm nonself-complementarity planar equiangular spiral, a z-directional helix, absorbing material with a stepped cylindrical honeycomb structure, and a ground plane. The z-directional helix is used to extend the current path and to improve the impedance matching and AR in the low-frequency band. The coupling between the nonself-complementarity planar spiral arms is increased, which improves the impedance matching in the low-frequency band and the AR at approximately 5.55 GHz. The stepped cylindrical absorbing material can reduce the reverse current and improve the AR in the high-frequency band. The measured results show that the impedance bandwidth and 3-dB AR bandwidths range from 0.5 to 6 GHz and from 0.5 to 5.8 GHz, respectively. The overall size of the proposed antenna is <inline-formula> <tex-math notation="LaTeX">$0.189\lambda _{L} \times 0.065\lambda _{L}$ </tex-math></inline-formula> (diameter <inline-formula> <tex-math notation="LaTeX">$\times $ </tex-math></inline-formula> height, where <inline-formula> <tex-math notation="LaTeX">$\lambda _{L}$ </tex-math></inline-formula> is the free-space wavelength at the starting frequency).
Physiological measurements of transition and resuscitation at birth

The neonatal transition is characterized by major physiological changes in respiratory and hemodynamic function, which are predominantly initiated by breathing and clamping of the umbilical cord. Lung aeration leads to the establishment of functional residual capacity, allowing pulmonary gas exchange to commence. This triggers a significant decrease in pulmonary vascular resistance, consequently increasing pulmonary blood flow and venous return. Clamping the umbilical cord contributes to these hemodynamic changes by altering the cardiac preload and increasing peripheral systemic vascular resistance. The resulting changes in the systemic and pulmonary circulations influence blood flow through both the oval foramen and ductus arteriosus. This eventually leads to closure of these structures and the separation of the pulmonary and systemic circulations. Most of our knowledge on human neonatal transition is based on human (fetal) data from the 1970s and extrapolation from animal studies. However, there is renewed interest in performing measurements directly at birth. By using less cumbersome techniques, (n.b. and probably more accurate), our previous understanding of the physiologic transition at birth is challenged, as well as the causes and consequences for when this transition fails to progress. This thesis provides an overview of physiological measurements of the respiratory and hemodynamic transition at birth.
Low-Loss, Thermally Insulating, and Flexible Rectangular Dielectric Waveguide for Sub-THz—Signal Coupling in Superconducting Receivers

Dielectric waveguides have potential as transmission lines in subterahertz (sub-THz) applications due to their low-loss. A new application of a rectangular dielectric waveguide (RDW) for a THz superconducting receiver system for radio astronomy is investigated and demonstrated for the first time. The RDW can be used to transmit sub-THz local oscillator (LO) signals into the cryostat for driving the superconductor insulator superconductor mixer, with very low heat transfer. A series of RDWs with different lengths are fabricated. The measured average attenuation constants of the RDW are 0.034 and 0.069 dB/mm at 3.4 and 300 K measurement environments over 240–300 GHz, respectively. The double-sideband system noise temperature of the receiver system is also measured. With this LO signal feeding system, there is only 0.69 mW thermal transfer power from the 300 to the 3.4 K cold stage. Compared to traditional pumping signal feeding schemes, such as the horn-to-horn structure and beam splitter method, this approach outperforms the traditional schemes in terms of feeding flexibility, insertion loss, and thermal isolation for the cryostat. The proposed RDW can be widely applied to superconducting receivers for radio astronomy in the future.
Securing Internet of Bio-Nano Things: ML-Enabled Parameter Profiling of Bio-Cyber Interfaces

The Internet of Bio-Nano Things (IoBNT) is an emerging paradigm at the cross-roads of Internet of Things (IoT), E-healthcare and synthetic biology. IoB Nt relies on innovating molecular communication between biologically synthesized nanodevices to facilitate in vivo drug delivery, remote monitoring and healthcare management via. the Internet. IoBNT therefore, requires robust security primitives to adequately address patient privacy concerns, increase physician confidence as well as limit (any) malicious operation resulting in bio-terrorism. The present work focused on securing the bio-cyber interfacing of IoB Nt technologies and considered three prevalent bio-electrical transduction techniques including bio-luminescence, redox modality and biological field effect transistors (BioFETs). Using the state-of-the-art machine learning (ML) algorithms, the proposed security framework employed parameter profiling the distinct operating features of bio-cyber interfaces and aimed to identify anomalous operation. During validation, an optimal profiling accuracy ranging between 88–91 % was recorded. The corresponding time complexity, scalability and qualitative analysis of the proposed parameter profiling-based framework leads to us to recommend it for further adoption in improving IoBNT security.
Tendon-driven Elastic Telescopic Arm -Integration of Linear Motion and Bending Motion-

The telescopic structure has a high extension-tocontraction ratio and is suitable for using a long manipulator that reduces the size of the structure because it is lightweight and small in diameter. There is a problem that conventional telescopic structures are only used in an open environment because it can not avoid obstacles on the axis of extension. In this paper, we propose a linear mechanism that can extend and contract one node at a time by a linear movement mechanism using a slide screw, and clarify its effectiveness by experiments. In addition, we control the tip position of the arm by the rope winding length and discuss the accuracy quantitatively. In addition, by integrating the linear mechanism and the bending mechanism, we achieved the linear motion while avoiding obstacles on the axis of extension.
Multi-Time Scale Thermal Simulation Simulation-Assisted Lifetime Prediction of Power MOSFE T in LED Driver

Power MOSFETs (Metal Oxide Semiconductor Field Effect Transistor) has become one of the reliability-critical components in LED (lighting-emitting diode) driver applications. The failure types, which are stressed by temperature variations, are the dominant mechanisms of discrete power MOSFETs. During the operation of LED drivers, the thermal cycles come from different time constants, ranging from microseconds (caused by MOSFET switching losses) to minutes/hours (caused by the changing of ambient temperature and loads). In order to comprehensively understand thermal behaviours of power MOSFETs, this paper proposed a multi-timescale thermal modelling method for the stress analysis and lifetime prediction of power MOSFETs considering its operating mission profile. For the small timescale (device switching), an electro-thermal transient thermal simulation of MOSFETs is proposed, where the electrical simulation and thermal simulation are carried out in SABER to evaluate the turn-on/turn-off losses and ANSYS Icepak to analyze thermal stresses, respectively. For the large timescale, the system-level thermal model of the LED driver is built to evaluate the converter-level stresses. Afterward, considering two typical mission profiles of street lighting, the lifetime of the power MOSFET is predicted by using this multi-time scale model. This method can provide a more realistic way to predict the lifetime of power MOSFETs under different operation profiles.
Performance Analysis of Overlapping Space-Based ADS-B Signal Separation Based on FastICA

Automatic Dependent Surveillance-Broadcast (ADS-B) is a main technology in the Air Traffic Management (ATM). Space-based ADS-B uses satellite to receive ADS-B signals can realize global surveillance. However, it also imposes an inevitable technical challenge: a high number of aircrafts cause the reception of superimposed messages, reducing the surveillance capability of the system. In this paper, FastICA algorithm is adopted to separate overlapping ADS-B signals and recover the source signals successfully. This paper also decodes the separated ADS-B signals and discusses the influence of signal power, relative delay and SNR on the separation of overlapping ADS-B signals. The simulation results show that the mixed signals can be separated successfully by using the FastICA algorithm when there is delay between the source signals. The decoding success rate of the separated ADS-B signal is better than that of overlapping signals and it becomes higher with the increasing of SNR.