Miracle-dz/UniFAR-FTUs huggingface dataset:
An analysis of triangulation reconstruction based on 3D point cloud with geometric features

The reconstruction of 3D point cloud is the core of reverse engineering and widely applied in industrial field. Focused on the problem of data redundancy and calculation, the reconstruction procedure is realized and the influence of various triangulation methods on geometric features is analyzed. The point cloud data pre-processing is implemented first based on C++ Point Cloud Library (PCL) in the paper, including filtering and smoothing, outlier removal, valid points extraction, simplification, and hole filling. Then the Greedy Projection Triangulation and the Poisson Reconstruction methods are applied separately to reconstruct the mesh models. The spherical center distance and diameter of calibration board are selected as the geometric characteristic parameters to assess the reconstruction quality. The relative error is calculated according to the true value and the average of multiple measurements on the parameters. For the distance feature, the results show that the two methods have similar accuracy. For the diameter feature, the Greedy Projection Triangulation is further suitable than the Poisson reconstruction, and the relative error of which is less than 0.18%.
A novel drain current I-V model for MESFET

The conventional approach for modeling the dc I-V characteristics of a MESFET transistor usually adopts the hyperbolic tangent dependence on V/sub ds/. On the contrary, our new empirical model describes the device drain current as a polynomial of effective gate-source voltage V/sub eff/. The derived model is capable of accurately modelling the subthreshold effect and the device current-voltage behavior at different operating regions, in particular, the device operation around the pinchoff region. Measured and modeled results of a 0.5-/spl mu/m gatelength MESFET device are compared and good agreement has been obtained. Comparisons between the proposed model, Curtice model, Chalmers model, and Parker model are also made in this paper. In addition, a single-stage class-AB amplifier was built with a commercial high-power MESFET transistor to verify the new model.
Active compliant parallel mechanism

An active compliant parallel device includes a movable body; a base body; and a plurality of linking members. The plurality of linking members are coupled to the movable body and the base body by a plurality of joints and include at least one compliant linking member, having a compliant element, and at least one actuating linking member, having an actuating element. The device may further include at least one damping linking member having a damping element and/or at least one passive linking member. The actuating, compliant, passive, and/or damping linking members are arranged in a parallel arrangement or structure such that each linking member makes a connection, using a connection element, such as a joint, with the base body and the movable body. The potential configurations of the device allow for movement and positioning of one or more unrestricted and externally loaded elements in space.
Advances and Applications of Hollow Fiber Nanofiltration Membranes: A Review

Hollow fiber nanofiltration (NF) membranes have gained increased attention in recent years, partly driven by the availability of alternatives to polyamide-based dense separation layers. Moreover, the global market for NF has been growing steadily in recent years and is expected to grow even faster. Compared to the traditional spiral-wound configuration, the hollow fiber geometry provides advantages such as low fouling tendencies and effective hydraulic cleaning possibilities. The alternatives to polyamide layers are typically chemically more stable and thus allow operation and cleaning at more extreme conditions. Therefore, these new NF membranes are of interest for use in a variety of applications. In this review, we provide an overview of the applications and emerging opportunities for these membranes. Next to municipal wastewater and drinking water processes, we have put special focus on industrial applications where hollow fiber NF membranes are employed under more strenuous conditions or used to recover specific resources or solutes.
Detecting Resource Contention in Virtualized Systems

Public and private cloud computing environments typically employ virtualization methods to consolidate application workloads on a single server for gaining cost and energy benefits. Contention among applications for shared server and virtualization resources can have a significant impact on application performance. Such contention can lead to resource bottlenecks that can especially be problematic for interactive applications such as Web servers that need to support fast response times for user requests. Previous work suggests monitoring hardware platform specific performance metrics for detecting such contention. This research shows that such metrics are not always sufficient for detecting contention, especially for highly concurrent interactive applications such as Web servers. A novel software probe based approach is presented for addressing this limitation. We show that the probe imposes a low overhead and is remarkably effective at detecting common performance degradations that can occur in environments featuring both interactive and batch style workloads.
Circularly polarised travelling-wave printed line antennas

The development of a broadband, circularly polarised antenna is presented. The configuration is based upon a travelling-wave microstrip line antenna. The experimental results are in good agreement with the numerical analysis. The experimental measurements show pattern bandwidths of 10 to 16% with input impedance bandwidths greater than 20%. The axial ratio is less than 3dB within the operating bandwidths.
Thermally excited silicon microactuators

A cantilever-type micromachined silicon actuator based on the bimetal effect used extensively for the fabrication of temperature-controlled electrical switches is described. The silicon actuator consists of a Si-metal sandwich layer and an integrated poly-Si heating resistor as a driving element. Due to the low heat capacity of the transducer element, a high temperature increase per input power unit can be achieved. For a (Si-Au)-cantilever-type actuator, 500- mu m long and several micrometers thick, a specific deflection of approximately 0.1 mu m/K at the free end has been measured. The design considerations, fabrication process, and experimental results of the actuator are discussed. >
Low‐noise photodiode detector for optical fluctuation diagnostics

The beam emission spectroscopy optical fluctuation diagnostic requires the highest possible quantum efficiency detector at 656 nm to minimize the photon statistical baseline limit to the detectable fluctuation level. A photoconductive photodiode detector with an extremely low‐noise preamplifier and a reactive feedback circuit provides quantum efficiencies up to 70%–80% for a useful frequency range of at least 0–150 kHz with incident powers of ∼10 nW. The diodes are chosen for negligible leakage current and hence do not require active cooling. These detectors have provided increase in the sensitivity to plasma fluctuation amplitude by a factor of ∼14 over photomultipliers and a factor of 4 over large area avalanche photodiodes.
Survey of current technologies for through-the-wall surveillance (TWS)

Recently, a survey was conducted for the Joint Project Steering Group (JPSG) of the National Institute of Justice (NIJ) and Defense Advanced Project Research Agency (DARPA)to determine the state-of-the-art at the present time in through-the-wall surveillance (TWS) technology and the expected advances within the next 10 years. The applicable technologies for TWS include: impulse radar, UHF/microwave radar, millimeter wave radiometry, x-ray transmission and reflectance, and acoustics. Proposed sensors include: monostatic radar, bistatic (or multistatic) radar, radiometers, fixed antenna systems, scanning systems, and focal plane array systems. The ability to penetrate walls leads to a natural conflict between the desire to successfully penetrate walls, which implies lower frequencies and the desire to obtain maximum resolution, which implies higher frequencies. Another conflict involves sophistication of the sensor versus unit cost. These issues and the approaches taken by various developers to find workable solutions are discussed.
Flank Wear Estimation in Turning Through Wavelet Representation of Acoustic Emission Signals

This paper investigates a flank wear estimation technique in turning through wavelet representation of acoustic emission (AE) signals. It is known that the power spectral density of AE signals in turning is sensitive to gradually increasing flank wear. In previous methods, the power spectral density of AE signals is computed from Fourier transform based techniques. To overcome some of the limitations associated with the Fourier representation of AE signals for flank wear estimation, wavelet representation of AE signals is investigated. This investigation is motivated by the superiority of the wavelet transform over the Fourier transform in analyzing rapidly changing signals such as AE, in which high frequency components are to be studied with sharper time resolution than low frequency components. The effectiveness of the wavelet representation of AE signals for flank wear estimation is investigated by conducting a set of turning experiments on AISI 6150 steel workpiece and K68 (C2) grade uncoated carbide inserts. In these experiments, flank wear is monitored through AE signals. A recurrent neural network of simple architecture is used to relate AE features to flank wear. Using this technique, accurate flank wear estimation results are obtained for the operating conditions that are within in the range of those used during neural network training. These results compared to those of Fourier transform representation are much superior. These findings indicate that the wavelet representation of AE signals is more effective in extracting the AE features sensitive to gradually increasing flank wear than the Fourier representation.
A Novel Deep Neural Network-Based Approach to Measure Scholarly Research Dissemination Using Citations Network

We investigated the scientific research dissemination by analyzing the publications and citation data, implying that not all citations are significantly important. Therefore, as alluded to existing state-of-the-art models that employ feature-based techniques to measure the scholarly research dissemination between multiple entities, our model implements the convolutional neural network (CNN) with fastText-based pre-trained embedding vectors, utilizes only the citation context as its input to distinguish between important and non-important citations. Moreover, we speculate using focal-loss and class weight methods to address the inherited class imbalance problems in citation classification datasets. Using a dataset of 10 K annotated citation contexts, we achieved an accuracy of 90.7% along with a 90.6% f1-score, in the case of binary classification. Finally, we present a case study to measure the comprehensiveness of our deployed model on a dataset of 3100 K citations taken from the ACL Anthology Reference Corpus. We employed state-of-the-art graph visualization open-source tool Gephi to analyze the various aspects of citation network graphs, for each respective citation behavior.
Effect of Hip Adductor Co-contraction on Trunk Muscle Activation during Bridge Exercise in Healthy Young Individuals

Purpose : Bridge exercise has been commonly used in clinical rehabilitation settings to improve trunk control, and hip adductor muscles were a related muscle that may affect trunk muscle activation. The aim of this study was to investigate whether the co-contraction of hip adductor muscles may affect trunk muscle activation during bridge exercises. Methods : Thirty-eight healthy young subjects (19 men and 19 women) performed bridge exercises (with and without hip adduction movement). Surface electromyography (EMG) data were collected from the dominant-side internal oblique (IO), rectus abdominis (RA), multifidus (MF) and erect spine (ES) during bridge exercises to compare trunk muscles activation patterns. Result : The EMG activities of IO and RA appeared to be significantly higher during bridge exercise with hip adductor co-contraction than during bridge exercise alone (p
Significance of GABAA Receptor for Cognitive Function and Hippocampal Pathology

The hippocampus is a primary area for contextual memory, known to process spatiotemporal information within a specific episode. Long-term strengthening of glutamatergic transmission is a mechanism of contextual learning in the dorsal cornu ammonis 1 (CA1) area of the hippocampus. CA1-specific immobilization or blockade of α-amino-3-hydroxyl-5-methyl-4-isoxazole-propionate (AMPA) receptor delivery can impair learning performance, indicating a causal relationship between learning and receptor delivery into the synapse. Moreover, contextual learning also strengthens GABAA (gamma-aminobutyric acid) receptor-mediated inhibitory synapses onto CA1 neurons. Recently we revealed that strengthening of GABAA receptor-mediated inhibitory synapses preceded excitatory synaptic plasticity after contextual learning, resulting in a reduced synaptic excitatory/inhibitory (E/I) input balance that returned to pretraining levels within 10 min. The faster plasticity at inhibitory synapses may allow encoding a contextual memory and prevent cognitive dysfunction in various hippocampal pathologies. In this review, we focus on the dynamic changes of GABAA receptor mediated-synaptic currents after contextual learning and the intracellular mechanism underlying rapid inhibitory synaptic plasticity. In addition, we discuss that several pathologies, such as Alzheimer’s disease, autism spectrum disorders and epilepsy are characterized by alterations in GABAA receptor trafficking, synaptic E/I imbalance and neuronal excitability.
ation, Artefacts a d Management S ies: The Personal

A study was undertaken to explore the artefacts and strategies used by mobile workers to manage their information. Using over 40 semi-structured interviews, a number of common features were found to hold across the sample group both in terms of the information that was maintained and the reasons why it was carried. These results suggest that there is a rich diversity of strategies for managing personal information, which may be embodied in common artefacts such as diaries and address books. Consequently, these results have a signifcant impact for the design of electronic devices for personal information management.
Compact CPW‐fed square aperture CP antenna for GPS and INMARSAT applications

This study proposed a coplanar‐waveguide‐fed square aperture circularly polarized (CP) antenna for the global positioning system and the International Maritime Satellite applications. The CP radiation is achieved by loading the aperture with a T‐shaped and a spur‐like strip. With the dimensions of the T‐shaped strip fixed, the CP radiation can be tuned to the desired band in a certain frequency range by adjusting the spur‐like strip. The measured 3‐dB axial‐ratio band is around 1.59 GHz with a bandwidth of 11.1% and a gain of about 3 dBic. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 427–430, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22147
Reduced Perceived Trustworthiness during Face Mask Wearing

To curb the diffusion of the novel coronavirus (SARS-CoV-2), governments worldwide have introduced different policies, including lockdowns, social distancing, and mandatory mask wearing. Face mask wearing, especially, has an impact on the formation of first impressions, given that when meeting someone for the first time, individuals rely on the only available piece of information, the newly met person’s aesthetic appearance, in order to make initial estimations of other traits, such as competence, intelligence, or trustworthiness. However, face mask wearing affects the aesthetic appearance of an individual, creating uncertainty which, in turn, has been reported to reduce others’ perceived trustworthiness. In this paper, the influence of face mask wearing on strangers’ perceived trustworthiness and aesthetic appearance is assessed to verify the impact of this policy on impression formation. Participants (N = 71) have been instructed to assess the trustworthiness and the aesthetic appearance of a selection of 96 images depicting individuals of different ages (children, adults, and older adults), gender (men and women), and ethnicity (Asians or Caucasians). Participants were randomly divided into two groups: an experimental group and a control group. Participants in the experimental group (N = 38) rated faces of individuals wearing a face mask, while participants in the control group rated the same faces but in the absence of a face mask. Images were presented in random order. For each face, participants were asked to rate the aesthetic appearance and perceived trustworthiness of the stranger on two different 100-point Likert scales. Results demonstrate that (i) the correlation between perceived trustworthiness and aesthetic appearance is not affected by the presence of a face mask, and (ii) age, but not ethnicity and gender, influences the magnitude of differences in perceived trustworthiness levels during mask wearing.
Intrinsic electric strength and electromechanical breakdown in polythene

The electric strength of polythene in the absence of surface discharges decreases sharply above room temperature, and there is evidence that this is an electromechanical effect. An optical-lever system, suitable for measuring electromechanical strains in recessed polythene specimens at 80° C, showed that true compressive strains were masked by a much larger movement of the whole recess caused by lateral expansion in the compressed polythene. When the movement was suppressed, no electromechanical compressions were detected, and there were indications of a significantly higher electric strength.The existence of an electromechanical effect was confirmed by comparing electric strengths of three grades of polythene over a range of temperatures and detecting differences caused by impulse and slowly applied d.c. electric stresses.
Improved selectivity compact band‐stop filter with Gosper fractal‐shaped defected ground structures

A novel band‐stop filter using Gosper fractal‐shaped defected ground structures has been designed and manufactured. The improvement in the filter selectivity has been achieved by introducing a multiresonance fractal‐shaped defect leading to a higher filter order, simultaneously maintaining its compact size. The experimental results prove the validity of proposed solution and its utility in novel miniaturized and severe requirement filter applications. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 227–229, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24869
Why every engineering student should study system dynamics

This paper makes the case that every undergraduate engineering student should study system dynamics. Parallel theoretical concepts in engineering and the social sciences, pressures from industry, and changes within the Accreditation Board for Engineering and Technology (ABET)frame the argument for system dynamics as a "non-technical" education requirement. Some of the distinct benefits of utilizing the basic thinking tools of system dynamics for the future engineer are discussed.
High Density Brine-Based Drill-In Fluid Improved Reservoir Producibility in Gas Field Offshore Egypt

Quick clean up and dramatic improvements in reservoir producibility have been achieved in gas wells located offshore Egypt. These wells were drilled and completed using an engineered drill-in fluid system. The fluid formulation was carefully designed and extensively tested in three different laboratories prior to the field applications to help ensure reproducibility of the data and to verify the non damaging characteristics of the fluid. These tests were conducted under simulated downhole conditions to help ensure fluid compatibility with the reservoir rock minerals and natural fluids. To help minimize fluid invasion while drilling in the payzone section, the optimal concentration and particle size distribution (PSD) of the suspended bridging material were selected and maintained during the field applications. The PSD of pure ground marble was selected based on the reservoir rock morphology and average pore size to establish effective bridging near the wellbore and help ensure quick lift-off of the filter cake. A high-density calcium chloride / calcium bromide brine blend (14-14.5 lb/gal ~ 1.68 sp.gr.-1.74 sp.gr.) was used as the base fluid to achieve and maintain the required fluid density without additions of insoluble weight material. Optimal concentrations of non-damaging temperature-stable polymers were used to provide suspension and filtration control. The gas reservoir section was drilled and completed in several wells with the new system. Productivity index and flow rates exceeded the operator’s expectations without any stimulation treatments. Substantial savings were realized in terms of rig time and well completion costs. This paper presents the laboratory and field-generated data and discusses the key issues in designing and monitoring the new drill-in fluid during the field applications.
A reliable source of information on botulinum toxin injection used in the treatment of spasticity: YouTube

Aim : The aim of the study is to assess the quality and reliability of YouTube videos on botulinum toxin injection for the treatment of spasticity. Material and Method : In this cross-sectional study, a search of YouTube videos was made on 15 September 2020, using the keywords "botulinum toxin and spasticity", "botulinum toxin treatment for spasticity", “spasticity management with botulinum toxin" "treating spasticity with botox". Two experienced reviewers on botulinum toxin injection on spasticity reviewed the first 200 videos. The quality of the videos was evaluated according to the Global Quality Scale (GQS) and three groups were formed: high quality, intermediate quality and low quality. The DISCERN tool was used to evaluate the reliability of the videos. Results : Of the 77 videos analyzed according to GQS, 36 (46.8%) were high quality, 31 (40.2%) were intermediate quality and 10 (13.0%) were low quality. Most of the videos (44.15%, n=34) uploaded by health professionals (physiatrist, orthopedist etc.) and the majority of the health professional groups had produced high quality videos (67.64%). When the parameters of the videos were compared according to quality levels, no significant differences were found in the number of view, comment, likes, dislikes, video length, days since upload (p>0.05). Significant differences were only found between the groups in respect of the DISCERN scores (p<0.001). Conclusion : YouTube can be considered as a reliable source for botulinum toxin injection in spasticity. The importance of the video source should be explained to the patient and healthcare professional using YouTube.
On the structure and packing of the moment matrix in problems supporting simultaneous electric and magnetic surface currents

An efficient packing algorithm is presented for filling the method of moments (MoM) matrix in problems containing both electric and magnetic currents, and multiple coupled regions separated by infinite conducting ground planes. Provision is made for symmetric and unsymmetrical submatrices. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 41: 500–505, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20184