Miracle-dz/UniFAR-FTUs huggingface dataset:
Automated structural bolt looseness detection using deep learning‐based prediction model

As one of the most common coupling elements in infrastructures, bolted joints play an important part in ensuring the integrity and safety of the whole system, whose failure may cause disastrous consequences. In recent years, precise detection and evaluation of bolt looseness have attracted numerous researchers' interest. However, the reliability of existing methods cannot be well guaranteed in long‐term field detection, and real‐time feedback is rather costly. This paper proposes a novel bolt looseness detection method based on audio recognition and deep learning. Firstly, a percussion experiment was designed to collect audio signals of bolts at different torque levels. Then, the time‐domain bolt percussion signals were converted into Mel‐frequency spectrograms, and the convolutional neural network (CNN) was adopted to mining deep information from the images for classification. To further verify the effect of different initial prestress levels on the vibration frequency of the bolted joint, a numerical study was conducted with the consideration of three different prestress levels. The results reveal that the proposed method has a high recognition accuracy in identifying bolt looseness conditions. Additionally, an iOS APP of acoustic vibration was established for real application. The prerecorded and untrained percussion audio was used to simulate the real‐time bolt looseness detection, which shows its potential in real future applications.
Analysis of the sound sources of lean premixed methane–air flames

Two investigations on the sound generation mechanisms of lean methane–air flames are reviewed and linked. A two‐step approach is used for the analysis. First, the compressible conservation equations are solved in a large‐eddy simulation formulation to compute the acoustic source terms of the reacting fluid. Second, the acoustic source terms are used in computational aeroacoustics simulations to determine the acoustic field by solving the acoustic perturbation equations. To identify the contributions of the different source terms to the overall sound emission of the flames different source term formulations are considered in the computational aeroacoustics simulations. The results of various flames of increasing complexity are shown: harmonically excited laminar flames, a turbulent jet flame, and an unconfined and a confined swirl flame. The results show that in general the heat release source alone does not determine the acoustic emission of the flame. Only the acoustic emission of the unconfined swirl flame could be computed by the heat release source. To accurately predict the phase and the amplitude of the sound emission of the other flames the acceleration of density gradients occurring at the flame front must be included in the considered set of source terms.
Performance evaluation of wireless MIMO radios

Next generation wireless radios demand for better spectral efficiencies and for high energy efficient (green) handhelds, and multiple-input multiple-output (MIMO) air interfaces represent a popular approach to address these challenges. In this work, spatial signal processing techniques in MIMO radios at different domains are evaluated with respect to their achievable performance, their power consumption and system sizes. Here, adaptive weighting in the analogue domain reveals several benefits compared to digital approaches. The obtained results are based on a four antennas receiver implementation in an 0. 25µm SiGe BiCMOS process.
¿Buscando al culpable? La estrategia discursiva en Twitter de los actores políticos populistas europeos en tiempos de crisis

Las democracias occidentales viven un impulso populista. En este contexto, la consolidación de las tecnologías digitales juega un papel clave por sus potencialidades para difundir con mayor facilidad los mensajes populistas. Esta investigación examina cómo los actores políticos populistas europeos introducen en su estrategia discursiva en Twitter la exclusión de grupos, el euroescepticismo y la existencia de crisis y cómo la enmarcan con el objetivo de conocer si existen diferencias significativas respecto a su ideología. La muestra está compuesta por los mensajes compartidos en Twitter por cuatro partidos políticos populistas europeos (Podemos, Movimiento 5 Estrellas, Frente Nacional y UKIP) y sus respectivos líderes (Pablo Iglesias, Beppe Grillo, Marine Le Pen y Nigel Farage y Paul Nuttall) durante tres periodos temporales fuera de campañas electorales. En total se han analizado 9.128 mensajes. Los principales hallazgos muestran que, pese a no ser características inherentes al fenómeno populista, la narrativa de la crisis, la exclusión de colectivos y el euroescepticismo está presente en el discurso de todos los actores políticos populistas analizados en Twitter. Todos ellos basan su estrategia discursiva en la búsqueda de culpables con el objetivo de presentarse ante el pueblo como la única opción política capaz de defenderles y devolverles la soberanía que les ha sido arrebatada. En este contexto, la ideología resulta determinante.
Single event upset in avionics

Data from military/experimental flights and laboratory testing indicate that typical non-radiation-hardened 64 K and 256 K static random access memories (SRAMs) can experience a significant soft upset rate at aircraft altitudes due to energetic neutrons created by cosmic ray interactions in the atmosphere. It is suggested that error detection and correction circuitry be considered for all avionics designs containing large amounts of semiconductor memory. >
An ACP-Based Parallel Approach for Color Image Encryption Using Redundant Blocks

Public concerns on image encryption grow significantly as the development and application of edge computing and the Internet of Things intensified recently. However, most existing image cryptosystems are not sophisticated enough to resist the two major attack strategies available currently, that is: 1) differential attacks and 2) chosen-plaintext attacks, which are famous for their destructive power, especially their capability of exploiting cryptosystems’ features to recover the secret key. In this article, we propose an artificial image, computational experiment, and parallel execution (ACP)-based color image encryption approach using redundant blocks. First, a redundant blocks strategy with redundant spaces is proposed to prevent differential attacks and accelerate operating speed while guaranteeing the security of image cryptosystems. Second, real-world chaotic data (e.g., stock data) are obtained to generate artificial images and conduct computational experiments. Furthermore, artificial images are encrypted via real-world chaos, while the original images are encrypted via simulated chaos (such as Chen’s hyperchaos). Finally, we design the process of parallel execution for image encryption and use DNA XOR to merge two groups of encrypted subimages to fuse the effect of the chaotic characteristics in both the real world and the simulation. The final encrypted image is realized through the recovery of redundant blocks. The ACP mechanism of color image encryption achieves the goal of improving the sophistication of chaos-based cryptosystems and resists both the differential and chosen-plaintext attacks. Experimental results and security analysis show that our approach provides not only excellent encryption but also security sufficient to prevent known attacks.
Performance Improvement of Pumps Fed by the Variable Speed Drives

Abstract Speed inaccuracy decreases the pump efficiency, reliability, and energy saving. This research is devoted to the determination of the ways of accurate speed control of the pump drives operated under changeable loads. The impact of speed inaccuracy on the pump performance is studied. Based on the analysis of methods for the static accuracy improvement, the drawbacks of the traditional approaches have been shown with reference to the pumping applications. A new methodology of the slip compensation has been proposed for implementation to improve the scalar drive performance. It notably decreases the speed inaccuracy of the open-ended pumping applications. The enhanced quality of the drive control at different loading conditions has been shown on a laboratory test bench. Also, for the multi-pump systems this approach results in an additional benefit from the viewpoint of the operation around the best operation point providing a safe pump control both to exclude the pump damage and to improve the process quality.
Quality of Service Aware - Modified DSR Protocol in Mobile Ad-Hoc Network

A Mobile Ad hoc Network (MANET) is a collection of wireless mobile nodes forming an infrastructure less network that has no centralized manager. Recently the work on quality of service Guaranties in adhoc networks have attracted more attention. Routing is challenging task in MANETs due to the dynamic behavior. Multipath routing allows load balancing to use of multiple paths for routing between a source-destination pair. Load balancing is a general technique that is applied to achieve QOS in MANETs. Multipath routing can increase end-to-end throughput and provide quality of service in networks. It exploits the resource redundancy and diversity in the underlying network to provide benefits such as fault tolerance, load balancing, increase throughput, and improvement in QoS metrics such as delay and packet loss. In this paper a modified DSR protocol is purposed which extend the existing DSR protocol. The proposed work is implemented in NS2 and evaluates its performance and compared with existing protocol. The results shows that Modified DSR achieves a higher rate of successful packet delivery than existing best-effort ad-hoc routing protocols, such as the Dynamic Source Routing (DSR).
Ergonomic Design of CNC Milling Machine for Safe Working Posture

In milling operation, Computer Numerical Control (CNC) milling machine has been recognized as one of effective solutions for high productivity, efficiency, and precision. However, the existing CNC milling machine has contributed to ergonomics-related problems such as awkward working posture. The aim of this study is to redesign the existing CNC milling machine by considering working posture of the machinist. This study performed questionnaire survey to determine ergonomics feature requirements from the machinist. The requirements of the machinist are then translated using Quality Function Deployment (QFD) to obtain technical specifications of new design CNC milling machine. The working posture of machinist during operating the existing CNC milling machine and the redesigned CNC milling machine was assessed using Rapid Upper Limb Assessment (RULA). Based on the analysis, the redesigned CNC milling machine has improved the working posture as shown by low score of RULA. This study concluded that by considering the ergonomics feature requirements to the design of CNC milling machine enabled the machinists to perform milling operation in safe working posture. This study suggests that environmental factors should be considered in the future research works.
17.4L: LateNews Paper: Contact Resistance and Process Integration Effects on HighPerformance Oxide TFTs with SolutionDeposited Semiconductor and Gate Dielectric Layers

Highperformance TFTs with solutiondeposited amorphous oxide semiconductor and gate dielectric layers are fabricated at ≤ 350 °C. The initial performance and stability of these TFTs are investigated with respect to device structure and source/drain materials. Topcontact TFTs exhibit better electrical performance and reliability than bottomcontact devices. Representative topcontact device mobility is 1.90 cm2/Vs with an ontooff drain current ratio of 7.0 × 108.
Constitutive Equations for an Induced-Strain Bending Actuator with a Variable Substrate

The constitutive equations for an induced-strain bimorph are derived for a transducer with a substrate that has a variable thickness and variable modulus. The constitutive equations for sensing and actuation are derived using an energy analysis for the case of a tip force, constant moment, and distributed pressure on the bimorph. The expression for each of the constitutive terms is equivalent to the expression for an ideal bimorph multiplied by a nondimensional modifier. For this analysis we define an ideal bimorph as one which has a negligible substrate thickness. The nondimensional modifier is only a function of two parameters: the ratio of substrate thickness to active layer thickness and the ratio of elastic moduli between the active material and the substrate layer. This allows the results to be easily compared to previous solutions for an ideal bimorph. Expressions for the blocked force, free deflection, and stored electrical energy are derived from the constitutive equations. The results demonstrate that stored energy and the effective coupling coefficient of the actuator do not vary appreciably for thickness ratios less than 1, indicating that actuator performance can be maintained even when the substrate thickness is an appreciable percentage compared to the thickness of the active layer. Blocked force and free deflection do change appreciably above thickness ratios on the order of 0.5, indicating that varying the thickness and modulus of the substrate layer is an additional design freedom in achieving tradeoffs in blocked force and free deflection with bimorph actuators. The results of this paper are useful for the design of bimorph transducers with specific performance requirements. The results also provide insight into some of the limitations exhibited by polymeric bimorphs actuated by an electric field. Our analysis demonstrates that the work output of a bimorph can be one to two orders of magnitude smaller than the stored mechanical energy when the active layer thickness is small compared to the overall bimorph thickness. This result is consistent with other models that suggest that the induced strain layer in certain ionic polymer materials is only a small portion of the overall transducer thickness. Experimental verification is provided on a series of bimorphs ranging from thickness ratios of approximately 0.1 to 10. Experimental results closely agree with the model predictions, although discrepancies become more significant as the thickness ratio approaches 10.
An Auto-Zero-Stabilized Voltage Buffer With a Quiet Chopping Scheme and Constant Sub-pA Input Current

This article describes an auto-zero stabilized voltage buffer that achieves low offset and low noise with sub-pA input current. A high gain stabilization loop is used to periodically cancel the buffer’s offset. The loop itself is periodically disconnected from the buffer and auto-zeroed, during which its bandwidth is reduced to reduce the associated noise folding. However, this also reduces its offset correction range, and so to avoid overloading, its initial offset is digitally trimmed. To break up the correlation between the residual low-frequency (LF) noise of the auto-zero and stabilization phases, the loop is periodically chopped, which significantly reduces the buffer’s LF noise. Finally, the duty-cycle of the two phases is optimized to bring the buffer’s LF noise density close to <inline-formula> <tex-math notation="LaTeX">$\sqrt {2}$ </tex-math></inline-formula> times its white noise density (14 nV/<inline-formula> <tex-math notation="LaTeX">$\sqrt {\text {Hz}}$ </tex-math></inline-formula>), which is the fundamental limit of an AZ amplifier. The buffer also achieves a constant and low input current (0.8 pA), as well as a state-of-the-art offset (0.4 <inline-formula> <tex-math notation="LaTeX">$\mu \text{V}$ </tex-math></inline-formula>).
Assessment of digital integrated circuit electromagnetic emission based on radiated power evaluation

This paper deals with the assessment of digital integrated circuit (IC) electromagnetic emission (EME), and concentrates on the specific aspect of EME of long external wiring, driven by IC input-output pins. In particular, the contribution of single IC pins is investigated by analyzing the structure composed of an IC output driver connected via a microstrip line to a receiver. A transmission-line model is used, and an approach based on the concept of radiated power is applied to the characterization of single-pin IC EME in terms of external-wiring radiation effects. By the analysis of typical driver-wiring configurations, it is shown that the spectrum of the driver output current is the quantity of interest, and that the use of wiring with smaller characteristic impedance leads to larger radiated power. The use of a specific test setup (IEC 61967-4-150-/spl Omega/ direct coupling method) for the experimental assessment of single pin IC emissions is also considered. Frequency-dependent setup effects are experimentally ascertained via a scattering parameter characterization, and definition of suitable circuit functions. An estimate of the degree of correlation between voltage measurements foreseen by the test procedure and the total power radiated by the loading network of an IC driver is derived.
THE THIN LINE BETWEEN FUNNY AND DISRESPECTFUL: MEDIA FRAMING ON PRABOWO’S ”BOYOLALI FACE” REMARK

The 2019 Indonesian Presidential Election is a democratic process for electing the President and Vice President of the Republic of Indonesia for the 2019-2024 period. Before the election was held, Indonesia's mass media was incessantly publishing news about presidential candidates, namely Joko Widodo and Prabowo Subianto Djojohadikusumo. As a retired army lieutenant general, Prabowo is known as a nationalist figure. This research aims to study Prabowo's image just before the 2019 Election in the online version of print media. We examine and compare the construction of Prabowo's image carried out by Tempo.co and Republika.co.id. We purposively select news published in Tempo and Republika online version from 4 to 5 November 2019. This research uses the qualitatively framing method by Entman to answer how the mass media carry out image construction. Results indicate that both media carry out a difference between construction. If Tempo tends to construct Prabowo's image as disrespectful, Republika tends to construct Prabowo's image as funny regarding Prabowo's "Boyolali Face" Remark. This study concludes that there are differences between the mainstream mass media and Islamic mass media in constructing Prabowo's image through their news. The different images constructed by the two media indicate that news construction or news framing is inevitable in the journalism field.
RELIABILITY OF RC MEMBERS STRENGTHENED WITH CFRP LAMINATES

Strengthening of concrete structures in flexure with externally epoxy-bonded carbon-fiber-reinforced plastic (CFRP) laminates is becoming an increasingly popular retrofit technique among researchers and engineers worldwide. A reliability study of such structures is the topic of this paper. First, considering the statistical character of the design variables (geometry, material properties), the effect of changes in these variables on the flexural capacity of CFRP-strengthened members is established. Variabilities in concrete strength and CFRP failure strain and area fraction are most influencial on flexural strength. Next, strength reduction factors are derived, with the aim of achieving a uniform reliability index of about three over a broad spectrum of design conditions. A general strength reduction factor φ= 0.80 is proposed. Finally, the effect of each design variable on the reliability of the system is examined and quantified in terms of the reliability index.
Asymmetric allelic introgression across a hybrid zone of the coal tit (Periparus ater) in the central Himalayas

Abstract In the Himalayas, a number of secondary contact zones have been described for vicariant vertebrate taxa. However, analyses of genetic divergence and admixture are missing for most of these examples. In this study, we provide a population genetic analysis for the coal tit (Periparus ater) hybrid zone in Nepal. Intermediate phenotypes between the distinctive western “spot‐winged tit” (P. a. melanolophus) and Eastern Himalayan coal tits (P. a. aemodius) occur across a narrow range of <100 km in western Nepal. As a peculiarity, another distinctive cinnamon‐bellied form is known from a single population so far. Genetic admixture of western and eastern mitochondrial lineages was restricted to the narrow zone of phenotypically intermediate populations. The cline width was estimated 46 km only with a center close to the population of the cinnamon‐bellied phenotype. In contrast, allelic introgression of microsatellite loci was asymmetrical from eastern P. a. aemodius into far western populations of phenotypic P. a. melanolophus but not vice versa. Accordingly, the microsatellite cline was about 3.7 times wider than the mitochondrial one.
The industries of London since 1861

1. Introduction 2. Source materials and their problems 3. The industrial structure of London 4. The older industries: clothing 5. The older industries: furniture 6. The older industries: printing 7. The older industries: conclusions 8. The new industrial areas 9. The newer industries: general engineering 10. The newer industries: electrical engineering 11. The newer industries: vehicles 12. The newer industries: conclusions 13. Planning and industry in London
Practical experience with the 'Variosens' equipment in measuring chlorophyll concentrations and fluorescent tracer substances, like rhodamine, fluorescein and some new substances

The quantitative measurement of the dispersion of matter in large bodies of water, e.g. in ocean currents [1] needs an opto-electronic fluorimeter of very high sensitivity due to the great quantities of the required fluorescent substances like Rhodamine B or Fluorescein. The basis of a new tracer technology of very high sensitivity is the use of pulsed bluish light for excitation [6, 7]. This instrument is known as the VARIOSENS. Due to R&D work, especially on filters, it is able to measure concentrations of fluorescent substances down to 10^{-12} . It has a logarithmic scale covering a concentration range of about 1:3000. The fluorescence is excited by means of a Xenon spark at a frequency of 10/s with stabilized light emission and a wide band optical filter which defines the exact spectral range of the required exciting light. The receiver operates with a narrow band optical filter by measuring the fluorescent radiation of the tracer substance used. This filter must have a very high blocking factor. Without filters the instrument uses backscatter to measure the quantity of suspended particles in the water in mg/litre.
Auto-orientation of an acoustically sensitive robotic wrist in a multipath environment

Auto-orienting robotic wrists are useful for mounting instrumentation modules whose operation depends on being accurately oriented in a time varying direction of interest. Such instrumentation includes video and narrow-beam communication systems as might be used on autonomous vehicles. This paper describes an underwater wrist which depends on an ultrashort baseline acoustic array for auto-orientation toward the first arrival of a sound burst in a multipath environment. <<ETX>>