Miracle-dz/UniFAR-FTUs huggingface dataset:
DESIGN OF A COMPACT MIMO ANTENNA FOR WIRELESS APPLICATIONS

—This paper presents a dual-band Multi-Input Multi-Output (MIMO) antenna design with acceptable isolation and compact size for wireless applications. The proposed antenna operates at two frequencies (2.75 GHz–5.3 GHz) and consists of two symmetrical monopoles with a T-shaped junction that is added on the upper layer of the substrate and used to connect the two monopoles and the ground plane. The T-shaped junction is added to enhance the isolation between the two antennas. Diﬀerent forms of slots have been etched on the ground plane to adapt the frequency bands to the desired frequencies. The simulations and measurement are used to examine the performance of the antenna in terms of S parameters, radiation patterns and the envelope of correlation coeﬃcient. The results show that the MIMO antenna has two resonance frequencies (2.75 GHz and 5.3 GHz), is suitable for WLAN applications and comes with a mutual coupling that is less than 12 dB. As a result, an envelope correlation coeﬃcient lower than 0.001 and a diversity gain higher than 9.98 dB are obtained, which means that the antenna has a remarkable diversity gain at operating bands.
The VolCo index: a measure of the transition from pandemic to equity market

ABSTRACT The COVID-19 has serious impacts on the economy and contaminates the equity market because its spread leads to enormous uncertainty, which can be measured by various volatilities from backward and forward information contents. We find that the pandemic-related data are significant for regressing various volatilities. Hence, we construct the index termed the Volatility of COVID-19 pandemic (VolCo) as a proxy of equity market volatility, including GJR-GARCH volatility, instantaneous volatility, VIX index and their combination. This VolCo index provides an explanation for the volatility of equity market in the period of COVID-19 spreads.
Wideband low-profile aperture-coupled circularly polarized antenna based on metasurface

Abstract In this paper, a metasurface-based aperture-coupled circularly polarized (CP) antenna with wideband and high radiation gain is proposed and analyzed. The proposed antenna is comprised of coplanar waveguide coupling with 4 × 4 corner truncated square patches, which show compact size and low profile. The mechanism of the CP antenna is analyzed theoretically based on the mode analysis and equivalent circuit analysis. The parameters of feeding structure and truncated corner are studied and optimized to achieve wide impedance bandwidth (BW) and axial ratio (AR) BW. Finally, an overall size of 38.8 mm × 38.8 mm × 3.5 mm (0.71λ0 × 0.71λ0 × 0.064λ0 at 5.5 GHz) CP antenna is proposed and fabricated. The simulated results demonstrate that over 41.7% impedance BW (S11 < −10 dB) of 4.55–6.95 GHz and 3 dB AR BW of 5.05–6.15 GHz (fractional BW is about 19.6%) are achieved. In addition, the antenna yielded a broadside CP radiation with a high gain average about 7.5 dBic. Experimental results are in good agreement with the simulated ones.
Rectangular Layer Model for Profile-based Human Action Recognition Using Multi-view Depth Information

Human action recognition is a fundamental step for understanding complex activities or behaviors, especially for video surveillance and health-care applications. In this paper we introduce a profile-based human action recognition from multi-view cameras using RGB-D information through the Rectangular Layer Model (RLM). Our model tends to improve the performance when the perspective distortion or the lack of information occurs due to the single-view approach. The fusion model is tested for five basic actions: walking and standing, sitting, bending, and laying, at different perspective viewpoints. The system can perform at 28.99 fps while its overall precision is significant at about 92.25%.
Achieving CramerRao Lower Bounds in Sensor Network Estimation

Achievable bounds for parametric estimation using sensor networks are known for some specific problems. In this article, achievable bounds for the general parametric estimation problem with fixed and varying parameters in the network and for various noise conditions on sensor nodes are studied. The general CramerRao lower bounds (CRLBs) of parameter estimates using sensor array network are derived. Procedures for reaching these bounds can be designed based on the obtained results. The accuracy of derived relationships is confirmed by an example. It is shown that it is possible to develop algorithms of moderate complexity and communication cost achieving the CRLB.
Dual-Buck Three-Switch Leg Converters With Reduced Number of Passive Components

Like conventional two-switch leg converters, the three-switch leg converters also have short-circuit risks and a dangerous shoot-through current is generated if switches of the same leg are turned on simultaneously. In this article, a new dual-buck structure is proposed for three-switch leg converters. The proposed structure is reliable because of no shoot-through concerns and high quality of output waveforms can be obtained due to the reduction in pulsewidth modulation deadtime. Unlike the conventional dual-buck three-switch leg that uses many passive components such as four current limiting inductors and three external diodes, the new dual-buck three-switch leg uses only one current limiting inductor with two external diodes. To verify the performance, the proposed three-switch legs are used in single-phase dual-output inverter and detailed theoretical analysis, simulation, and experiments are performed. Both continuous and discontinuous modulation schemes are applied and it has been figured out that discontinuous modulation scheme can improve the dc-link voltage utilization in the common-frequency mode of operation.
Analysis of the Dilemma of Promoting Circular Logistics Packaging in China: A Stochastic Evolutionary Game-Based Approach

The environmental pollution caused by logistics packaging in China has attracted increasing attention in recent years, and circular packaging is considered an effective means to solve the aforementioned problem. Therefore, this study considers the uncertainty of the external environment; constructs a stochastic game model of circular logistics-packaging promotion, which consists of environmental regulators, logistics enterprises, and consumers; collects data related to logistics packaging in China to describe the current circular-packaging promotion dilemma; and conducts a parameter-sensitivity analysis. The results show that (1) after a short period of fluctuation, the environmental regulator will lock in the “strong regulation” strategy, whereas logistics enterprises and consumers will quickly lock in the “no promotion” and “negative use” strategies. (2) The change in the initial probability will affect the rate of strategy evolution of the gaming system. (3) The “strong regulatory” strategy of environmental regulators and the increase in the number of circular-packaging cycles can help establish a logistics-recycling-packaging system. (4) The increase in recycling incentives can cause consumers to shift toward “active use” strategies, but this has accelerated the rate at which logistics companies lock into “no promotion” strategies. (5) The increase in the intensity of random interference will raise the fluctuation of the evolution of the game subject. For logistics enterprises, moderate random interference helps them evolve toward the “promotion” strategy.
SARSCOV‐19 amidst corruption: Does the civil society matter? – An empirical study

The pandemic outbreak has dealt consequences on global engagements and structures. With the ongoing search for pandemic‐mitigating measures and the excesses (notably corruption) erupted in its wake, concerns have been raised about the decline in public trust, transparency and satisfaction – particularly in Ghana. This situation has spurred multilevel governance discussions regarding pandemic management. Ensuingly characterising policy makers' propositions in this regard is the civil society's salience as a control valve to governance deficits like corruption. Therefore, transcending the anecdotal claims on civil society's efficacy, this study takes a state‐society perspective to probe its relevance in fostering trust, transparency and satisfaction, relative to corruption‐stricken pandemic governance. The current study engages the general systems theory as a conceptual lens. The structural equation modelling technique was used in analysing data (n = 519) gathered through the questionnaire survey approach. Though results of data analysis affirmed the negative effects of corruption on trust, transparency and satisfaction, the civil society received affirmation as an enhancer of trust, transparency and satisfaction. In view of these study findings, implications and future research suggestions are delimited.
Transient Stability Enhancement Using a Wide-Area Controlled SVC: An HIL Validation Approach

This paper presents a control scheme of a wide-area controlled static VAr compensator (WAC-SVC) and its real-time implementation in a hardware-in-the-loop (HIL) simulation scheme with three control objectives: (1) to increase the critical clearing time, (2) to damp the power oscillations, and (3) to minimize the maximum line current. The proposed control scheme considers a correction strategy to compensate the delays up to 200 ms. In addition to this, a generator tripping scheme based on synchrophasor measurements to determine the proximity to the loss of synchronism is proposed. A delay compensation algorithm based on polynomial approximations is also developed. The proposed WAC-SVC is experimentally validated using a Real-Time Digital Simulator platform (RTDS), industrial communication protocols, a commercial device for PMU-based control implementations, and digital relays with PMU capability. The real-time simulation results confirm its effectiveness and feasibility in real industrial applications. Furthermore, practical guidelines to implement this kind of control schemes are provided.
Coenzyme Q10 and Parkinsonian Syndromes: A Systematic Review

Coenzyme Q10 (CoQ10) has an important role as an antioxidant. Being that oxidative stress is one of the mechanisms involved in the pathogenesis of Parkinson’s disease (PD) and other neurodegenerative diseases, several studies addressed the concentrations of CoQ10 in the different tissues of patients with PD and other parkinsonian syndromes (PS), trying to elucidate their value as a marker of these diseases. Other studies addressed the potential therapeutic role of CoQ10 in PD and PS. We underwent a systematic review and a meta-analysis of studies measuring tissue CoQ10 concentrations which shows that, compared with controls, PD patients have decreased CoQ10 levels in the cerebellar cortex, platelets, and lymphocytes, increased total and oxidized CoQ10 levels in the cerebrospinal fluid and a non-significant trend toward decreased serum/plasma CoQ10 levels. Patients with multiple system atrophy (MSA) showed decreased CoQ10 levels in the cerebellar cortex, serum/plasma, cerebrospinal fluid, and skin fibroblasts. Patients with Lewy body dementia (LBD) showed decreased cerebellar cortex CoQ10, and those with progressive supranuclear palsy (PSP) had decreased CoQ10 levels in the cerebrospinal fluid. A previous meta-analysis of studies addressing the therapeutic effects of CoQ10 in PD showed a lack of improvement in patients with early PD. Results of the treatment with CoQ10 in PSP should be considered preliminary. The potential role of CoQ10 therapy in the MSA and selected groups of PD patients deserves future studies.
Real-Time Construction of Thermal Model Based on Multimodal Scene Data

In commercial buildings, the total consumption of central air conditioning accounts for about 40%–50%. However, at present, the initial design value of building Heating Ventilation and Air Conditioning (HVAC) is usually far greater than the actual refrigeration value of refrigeration demand, which will lead to great energy consumption waste. Moreover, the operation of HVAC affects the thermal comfort of users, so it is necessary to establish a thermal model for the scene to control. The thermal model describes the temperature of the scene in different environments. So it is very important to design a thermal model to calculate the scene in real time. Because the flow of people, the opening of windows, the ventilation of the scene and other parameters influence the change of thermal state in the scene environment, these parameters are complicated to model. Human disturbance will lead to the instability of the state of the scene environment. The inconsistency of its thermal model will lead to energy allocation tracking strategies in different regions. To solve this problem, We propose a thermal model for building thermal comfort using a multimodal analysis framework. This paper analyzes multiple temperature and humidity sensors and area image by multimodal combination and processes the image and sensor data by combining CNN and LSTM. Our results show that when the thermal model analyzed by this method is deployed in a building in the south of China, the MSE accuracy of the local effect of temperature field prediction reaches 99%, and its AMAX reaches 94%, so the running stability of the model in the scene is high. In addition, the research shows that the thermal model analysis framework can make the Internet of Things (IoT) in buildings more intelligent, and it can be combined with this thermal model to improve human comfort, make it easier to deploy in each hot zone, and have a better overall energy-saving effect.
Exploring the Mechanism of Hawthorn Leaves Against Coronary Heart Disease Using Network Pharmacology and Molecular Docking

Hawthorn leaves, which is a traditional Chinese medicine (TCM), has been used for treating coronary heart disease (CHD) for a long time in China. But the limited understanding of the main active components and molecular mechanisms of this traditional medicine has restricted its application and further research. The active compounds of hawthorn leaves were obtained from TCMSP database and SymMap database. The targets of it were predicted based on TCMSP, PubChem, Swiss Target Prediction, and SymMap database. The putative targets of CHD were gathered from multi-sources databases including the Online Mendelian Inheritance in Man (OMIM) database, the DrugBank database, the GeneCards database and the DisGeNet database. Network topology analysis, GO and KEGG pathway enrichment analyses were performed to select the key targets and pathways. Molecular docking was performed to demonstrate the binding capacity of the key compounds to the predicted targets. Furthermore, RAW264.7 cells stimulated by lipopolysaccharides (LPS) were treated with three effective compounds of hawthorn leaves to assess reliability of prediction. Quercetin, isorhamnetin and kaempferol were main active compounds in hawthorn leaves. Forty four candidate therapeutic targets were identified to be involved in protection of hawthorn leaves against CHD. Additionally, the effective compounds of it had good binding affinities to PTGS2, EGFR, and MMP2. Enrichment analyses suggested that immune inflammation related biological processes and pathways were possibly the potential mechanism. Besides, we found that three predicted effective compounds of hawthorn leaves decreased protein expression of PTGS2, MMP2, MMP9, IL6, IL1B, TNFα and inhibited activation of macrophage. In summary, the present study demonstrates that quercetin, kaempferol and isorhamnetin are proved to be the main effective compounds of hawthorn leaves in treatment of CHD, possibly by suppressing expression of PTGS2, MMP2, MMP9, inflammatory cytokines and macrophages viability. This study provides a new understanding of the active components and mechanisms of hawthorn leaves treating CHD from the perspective of network pharmacology.
Cruise missile head shape optimisation using an adaptive sampling surrogate model

ABSTRACT High-precision response of the surrogate model is desired in the process of optimisation. An excessive number of sampling points will increase the cost of the calculation. The appropriate number of sampling points cannot only guarantee the accuracy of the surrogate model but also save the calculation cost. The purpose of this research is to demonstrate the eventuality of using an adaptive surrogate model for optimisation problems. The adaptive surrogate model is built on an adaptive sampling approach and an extended radial basis function (ERBF). The adaptive sampling is an approach that new sampling points are placed in the blank area and all the sampling points are uniformly distributed in the design region using Multi-Island GA. The precision of the ERBF surrogate model is checked using standard error measure to determine whether the surrogate model should be updated or not. This adaptive surrogate model is used to optimise a cruise missile head shape. Aerodynamic and stealthy performance of the cruise missile head shape are considered in this research. Different global objective function and different weight factor are used to research the aerodynamic and stealthy performance in this optimisation process. The results show that the drag is reduced with a slender head shape and the radar-cross section (RCS) value is reduced with a short head shape.
Influence of environmental factors and body condition on the post-oviposition behavior in the emerald glass frog Espadarana prosoblepon (Centrolenidae)

In species with parental care behaviors, parents may adjust the intensity and duration of their care if fluctuation in factors such as environmental variables or body condition affects offspring survival. In the face of environmental changes, many egg-laying species remain with their clutch for extended periods if this behavioral adjustment provides tangible benefits to the offspring. However, the length of time parents stay with the offspring may also differ depending on the individual’s body condition. In the glass frog family (Centrolenidae), several species exhibit long-term egg attendance in which they remain with their clutch for several days after oviposition takes place. For some of them, changes in environmental variables lead to increased parental care efforts. For the species in which parents remain with their offspring for a short period (less than 24 hours), it is less clear if this constitutes parenting behavior, and whether parents adjust their efforts as a function of environmental change or the parent’s body condition remains unexplored. We studied a population of the Emerald Glass Frog, Espadarana prosoblepon, a species that exhibits a short period of quiescence after oviposition (less than three hours). Our study aimed to determine whether females alter the length of their post-oviposition quiescence period in response to changes in environmental variables (i.e., temperature, humidity, rainfall, and mean wind speed) or female body condition. Pairs in amplexus were captured in the field and transported to semi-natural enclosures to record the duration of post-oviposition quiescence using infrared cameras. Females’ post-oviposition quiescence lasted an average of 67.4 ± 26.6 min (range = 22.7–158.3 min). We did not find a significant relationship between the duration of the post-oviposition quiescence and any of the environmental variables tested. Similarly, post-oviposition quiescence duration was not influenced by female body condition. Because the variation observed in the duration of post-oviposition quiescence was not related to changes in extrinsic (environmental) or intrinsic (body condition) factors, we found no evidence that females of E. prosoblepon modify their post-oviposition behavior in response to any of the variables examined in this study. Future research investigating the adaptive significance of the post-oviposition quiescence observed in this species is needed to understand how this behavior is related to parental care efforts.
Towards high modulation bandwidth using two-section InP-on-Si DBF laser diodes

There is an increasing interest in silicon photonics, mainly due to the advantages of dense integration of active and passive optical functions and the possibility of co-integration with electronics. However, when it comes to light sources, silicon cannot be used on its own due to its indirect bandgap. This motivates research on heterogeneous integration of III-V materials on silicon to create light sources. The basis of this process is bonding IIIV material on silicon, and is described in details in [1]. DFB laser diodes are the preferred light sources for many applications, due to their single mode behavior and high Side-Mode-Suppression-Ratio (SMSR). Previous research has already explored different methods to create DFB laser diodes on the InP-on-Si platform for various applications, such as high-speed modulation [2, 3], wavelength tuning [4] and self-pulsations [5]. Recent research has demonstrated the superior performance of high speed modulated DFB laser diodes on the InP-on-Si platform. 56 Gbps directly modulated lasers were demonstrated in [2]. In more recent work [3], electro-absorption modulation of the two laser tapers allowed 2 x 56 Gbps modulation speed. Further improvement is desired to speed up the transition to 400 Gb/s or Tb/s Ethernet. Though single section InP-on-Si DFB laser diodes are limited by their relaxation oscillation frequency, some design alterations can enhance the modulation bandwidth, e.g., creating an external cavity to exploit a Photon-Photon-Resonance (PPR) which has resulted in a 34 GHz modulation bandwidth [2]. In parallel, there have also been some investigations on two-section DBR [6] and DFB laser diodes [7]. Simulations show that such two-section laser diodes (also referred to as coupled cavities), enhance the modulation bandwidth to values as high as 40 GHz [6, 7]. This paper summarizes the findings obtained from experiments on a two-section DFB laser diode, whereby a small signal modulation resulted in a 3-dB modulation bandwidth of 30 GHz. Judging from the small signal response, it is expected to have error-free transmission for 56 Gbps Non-Return-to-Zero (NRZ) signals, and beyond. However, the highest possible modulation speed that complies with the Forward-Error-Correction (FEC) criteria of 10 Bit-Error-Rate (BER) is 40 Gbps NRZ. We believe that the limitation is due to the multi-mode behavior of the laser, as the laser was fabricated with minimum bonding thickness resulting in a very high coupling coefficient. Further optimization to obtain a single-mode laser, e.g., by increasing the bonding thickness to decrease the coupling coefficient, promises high modulation bandwidths. Proceedings Symposium IEEE Photonics Society Benelux, 2017, Delft, The Netherlands
Application of microstrip filter for multiple narrow band antenna to detection of partial discharge

The ultra-high frequency (UHF) antennas are used as sensors to detect electromagnetic (EM) waves emitted from partial discharge (PD) in the high voltage insulation diagnostic field. However, the UHF band includes many communication and broadcasting frequencies, such as cellular phones and Wi-Fi. The authors have developed a multiple narrow-band antenna (MNB) to detect PD signal in the UHF band without radio communication noise that corresponds to several narrowband frequencies used for mobile phones and Wi-Fi. This study proposed the filtered multiple narrow band (FMNB) antenna, which consists of a multiple-strip monopole antenna and microstrip low pass filter (LPF, fC=2GHz) on an FR-4 substrate. The microstrip LPF improves the reduction of high-frequency noises without antenna size extension, especially 2.4 GHz Wi-Fi noise. The FMNB antenna was applied to detect the PD in SF6 gas under the Wi-Fi noise emitted from a commercial drone and compared with a standard Horn antenna (HA), one of the high sensitivity wide-band antenna. The experimental results demonstrate that the FMNB antenna is suitable for PD detection in the UHF method under noisy conditions.