Miracle-dz/UniFAR-FTUs huggingface dataset:
Feasibility of energy harvesting from a rotating tire based on the theory of stochastic resonance

Recently the use of nonlinear bi-stable micro-electro mechanical systems (MEMS) to achieve automobile tire vibration power generation has made some progress. However, the theory of stochastic resonance has not been successfully applied to automobile tires, which can produce a larger vibrational response than for a typical resonance while inputting a weak periodic force and noise excitation into a nonlinear bi-stable system. Hence, in this paper, in view of the principle of stochastic resonance, a new model is derived by positioning a magnetic end mass attached to a cantilever beam and another permanent magnet with the same polarity on the frame. Due to the road noise excitation along with the periodic force inputted to the mechanism, whether the phenomenon of stochastic resonance can happen will be discussed. Meanwhile, on the basis of Kramers rate and duffing equations the preliminary experimental device is also designed.
HIMA-Net: humor prediction by self-attention based on key information related to humor

Humor is a high-level semantic emotion that can only be understood at a stage when the human mind has developed. Humor detection is a challenging task in the field of natural language processing. In this paper, we focus on the characteristics of humor from the way it is generated and propose the Humor Important Message Attention Net (HIMA-Net): a self-attention network based on the key messages related to humor. Results show that HIMA-Net outperforms the traditional models on three datasets (Headline, Pun, Short Jokes), and further analysis demonstrates the effectiveness of the proposed model.
Circular microstrip antenna with dual band‐stop performance for ultrawideband systems

In this article, a novel small monopole antenna with dual band‐notched characteristic for ultrawideband applications is proposed. The proposed antenna consists of circular‐disc radiating patch with a rotated T‐shaped slit, a feed line with a rotated Ω‐shaped split‐ring resonator, and a ground plane. The designed antenna has a small size. The simulated and measured results show that the antenna design exhibits an operating bandwidth (VSWR < 2) from 2.86 to 12.92 GHz with 3.3–4.2 and 5–6 GHz rejected bands covering all the 5.2/5.8 GHz wireless local area network, 3.5/5.5 GHz worldwide interoperability microwave access, and 4 GHz C bands. Good antenna gain and radiation pattern characteristics are obtained in the frequency band of interest. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:2095–2098, 2014
On-orbit performance prediction of the heat receiver for the US/Russia solar dynamic power flight experiment

A joint US/Russia program has been conducted to develop, fabricate, launch and operate a solar dynamic experiment on Space Station Mir. The goal of the program was to demonstrate and confirm that solar dynamic power systems are viable for future space applications such as the International Space Station. The major components of the system include a heat receiver, a closed Brayton cycle power conversion unit, a power conditioning and control unit, a concentrator, a radiator, a thermal control system and a Space Shuttle carrier. This paper discusses the on-orbit performance of the heat receiver component. The receiver comprises a cylindrical cavity, the walls of which are lined with a series of tubes running the length of the cavity. The engine working fluid, a mixture of xenon and helium, is heated by the concentrated sunlight incident on these tubes. The receiver incorporates integral thermal storage, using a eutectic mixture of lithium fluoride and calcium difluoride as the thermal storage solid-to-liquid phase change material. This thermal storage is required to enable power production during eclipse. The phase change material is contained in a series of individual containment canisters. The experiment has been "demanifested" from its expected Space Shuttle launch. As such, the complete flight system will not be fabricated at the present time.
Modeling and Analysis of Air Defense Process for Warship Formation Based on PEPA

Air defense process of large surface warship formation is a very important part in the combat. In current research, however, less attention has been paid to the whole process of air defense of surface warship formation in macro perspective. This paper applies the PEPA method to model the air defense process of surface warship formation. The cooperation among elements has been taken into account in the established model and the basic process of the air defense has been described as well. By analysis it shows the performance of air defense of warship formation increases with the increase of elements’ quantity, and finally reaches a stable value. Then the composition of the basic formation elements that the interception capacity of air defense operation attains the maximum can be obtained from the test results. Therefore, it provides a new quantitative method to deal with the air defense problem of warship formation.
Processing of Ni-based aero engine components with repetitively Q-switched Nd:YAG lasers

Aircraft engine industry uses free running high power Nd:YAG lasers for drilling cooling holes into nickel base alloy turbine components. A cw-pumped, Q-switched, high beam quality laser system with 400W laser power is presented. The laser is used to trepan drilling of 1.6mm. Hastelloy X sheets and ceramic coated combustion chamber tubes of the same metal. Cylindrical shape, uniformity, and reproducibility are achieved with a trepan-like drilling setup. The heat load of the workpiece as well as the process time is considerably decreased by employing high-repetition Q-switched lasers.
An identification of body segment parameters in the upper extremity

This paper presents a method for identifying static parameters of all three upper extremity segments. An industrial robot was used for moving the subject's arm along a specified sagittal trajectory during which measurements of the shoulder, elbow and wrist angles and forces in the contact point were collected. An identification procedure was developed in analogy with those performed on industrial robots, which assumes the upper extremity model of a 3DOF planar structure in a closed kinematic chain. At first, a suitable trajectory had to be obtained in all three joints with appropriate low speed and with very small angle deviations around an operating point. The arm was assumed to be linear in this point since passive properties of the arm showed no nonlinearities for such small angular deviations. Since the imposed movements were very slow all dynamic effects could be discarded, which simplified the mathematical complexity. By programming a suitable trajectory into the robot controller the ill conditioning problem, could be improved significantly. The algorithm eventually identifies masses and mass center coordinates for the lower arm and palm segments, their products for the upper arm and the operating point passive moments (summed elasticities and Coulomb frictions) for all three joints in the sagittal plane. The results are eventually compared to the literature estimations which are based on average population.
Implementation of a parallel zero-voltage switching forward converter with less power switches

A parallel zero-voltage switching (ZVS) forward converter is proposed to achieve load current sharing, output ripple current cancellation and conversion efficiency improvement. Two forward converters are connected in parallel to achieve interleaved pulse width modulation operation. Thus, the ripple currents on the output side are partially cancelled on each other so that the size of output chokes and capacitor is reduced. Only two switches are used in the proposed converter instead of four switches in the conventional parallel ZVS forward converter. Therefore the proposed converter has less power switching devices. An active snubber is connected between two power transformers to absorb the energy stored in the leakage and magnetising inductances of transformers, to limit voltage stresses across switches and to realise the ZVS turn-on of all switches. Thus, the conversion efficiency is improved by the soft-switching operation of switching devices. Finally, the performance of the proposed converter is evaluated on a 480 W (24 V/20 A) laboratory prototype.
Application of Multivariate Statistical Models to Prediction of NOx Emissions from Complex Industrial Heater Systems

Industrial fired heaters are a major source of nitrogen oxides ( NOx ). On-line analyzers, kinetic models with computational fluid dynamics, and empirical predictive models have been developed to monitor NOx emissions and analyze excessive NOx emissions. However, previous approaches have been applied only to single heater systems, not to large-scale multiheater systems. This paper proposes a hierarchical monitoring and diagnosis procedure to monitor NOx emissions from large-scale multiheater systems and to identify the root causes of excessive NOx emissions as well as heater malfunctions. The procedure provides a functional three-layer hierarchy: (1) prediction of NOx concentrations; (2) estimation of the influence of individual heaters on the predicted NOx ; and (3) identification of the root causes by examining the detailed contributions of process variables to variations of the heater identified in step 2 as being the principal source of NOx . An integrated multiblock partial least-squares (PLS) model,.
Dynamic Model Identification of Marine Electric Propulsion System

This paper applies identification technique to the marine electric propulsion system analysis, adopts the recursive extended least squares (RELS) algorithm to estimate the structure and parameters of the model, employs the variable forgetting factors into the algorithm to improve the tracking characteristic of the parameters, establishes the dynamic model of a simulated electric propulsion unit under the excitation control based on the experiment data, and finally verifies the validity of the method through the consistency between simulation result and experimental result.
Reconfigurable scan‐beam hollow patch reflectarray antenna loaded with tunable capacitor

In this article, the design concept of an active reconfigurable reflectarray antenna has been proposed and tested. The elementary radiators are hollow patch element loaded with varactor‐diode device in which the reflected phase can be varied. This phase alteration is based on the variation of the diode capacitance which can be achieved by varying the biasing voltage of the active varactor device. By activating these varactor devices, the phase of each antenna element in the array configuration can be adopted dynamically, and consequently, its radiation beam direction can be reconfigured. The advantage of the MEMS switches is the complexity of the integration and continuing beam scanning capability. The reflectarray incorporating active elements has been built and tested at 6.0 GHz. Narrow band multifrequency shared aperture is demonstrated theoretically and experimentally. The performance of the proposed active antenna is excellent, which pioneers the design of arbitrarily reconfigurable antennas. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 367–374, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24050
JETFIRE: A Low-Cost, Trusted IoT Security Gateway

Many studies have pointed out security problems with IoT deployments. Given the diversity of devices and the lack of concerted efforts from device manufacturers to adopt best practices, recent efforts have recommended pragmatic “bolt on” security gateways at the network layer to secure IoT deployments using software-deﬁned principles. While such gateways are an attractive option, they raise two natural concerns: (1) Can the gateway architecture be trusted? and (2) Can we deliver these beneﬁts to low-cost deployments? This paper presents J ETFIRE , a practical, low-cost system with built-in trust for software-deﬁned security gateways. In designing and implementing J ETFIRE , we make three key contributions: (1) A practical and deployable basis for trust using a micro-hypervisor root-of-trust; (2) A scalable low-cost system design and implementation to support ﬁne-grained per-device policies; and (3) A formal analysis of the protection J ETFIRE offers against infrastructure threats by construction. We demonstrate that J ETFIRE provides intrinsic security against a broad spectrum of known attacks against such software-deﬁned architectures. We also show that J ETFIRE offers security at low cost; e.g., a $35 Raspberry Pi can effectively support custom per-device IPS instances for a small IoT deployment of 50+ devices. We also show an end-to-end validation of J ETFIRE on a representative home IoT deployment.
Design of devices for protecting civil structures using fixed‐order ℋ︁∞ control

Devices for protecting civil structures against external disturbances such as seismic waves or dynamic loads are computed by using fixed‐order ℋ︁∞ controllers in this paper. Several solutions for the controllers are analysed and compared in order to obtain the most suitable solution for their application to protect buildings, specially for those buildings that are already constructed but not conveniently protected. A new pseudo‐hybrid solution is also proposed, designed and compared to other alternatives with very promising results. The obtained fixed‐order ℋ︁∞ controllers are simpler but similar in performance to those obtained with conventional control techniques. Moreover, they are also more reliable because of the economy in the number of components. Copyright © 2005 John Wiley & Sons, Ltd.
Numerical Investigation of Flow-Induced Vibration of a Cantilever Beam for a Piezoelectric Energy Harvester

Flexible cantilever beams in channel flow loses its stability through a flutter mechanism at sufficiently high Reynolds number. This sustained transfer of flow work to cantilever beam oscillation could be extracted to generate electrical power, which may be utilized to power wireless sensors for structural health monitoring or supply additional power in unmanned or micro air vehicles. Such flexible beam system is known to exhibit some form of hysteresis, with super- and sub-critical velocities for onset of flutter, which may not be captured by current potential flow modeling. We present numerical simulation of a viscous, Navier-Stokes solver coupled to a cantilever beam, to capture this flutter velocity hysteresis. Numerical result under a linearly varying flow velocity shows an approximately 11% hysteresis, suggesting potential of present model for identifying more accurate boundaries of beam flutter. The prediction of cantilevered piezoelectric beam response under varying or unsteady flow velocities is necessary for reliable design of energy harvesting devices and warrants further experimental investigations.
Improved design of the Vivaldi antenna

The Vivaldi antenna and its feeding transition is investigated. A tapered transition from microstrip to symmetric double sided slot line, fabricated on a low dielectric constant substrate, exhibits a very wide operating frequency range, with no need for a shorting hole. The parameters of the antenna which influence the constancy of beamwidth with frequency are discussed, and the ability to determine the required beamwidth by controlling the antenna length is shown.
Design of intelligent hybrid supervisory controller based on temporal neural networks and timing modules

This paper investigates the application of temporal neural networks in designing sequence controllers for time and event driven mechatronic manufacturing systems (MMSs). A proposed design of this controller is presented. The proposed design is based on temporal neural network algorithm with timing modules. Adequate guidelines of constructing the controller are presented. These guidelines are applied to design a controller for an industrial application. Functionality of the proposed controller is tested by simulation. Learning process, functionality and main features of this controller are studied and analysed. Theoretical results are presented and discussed. These results prove the proper functionality of the controller to deal with a time and event driven discrete manufacturing system. In addition, the simulation results assure the effectiveness of the proposed controller to outperform the effect of noisy inputs.
Kindergarten Teachers Training in Integrating Anti-Corruption Education through Storytelling and Game

There are many ways to prevent corruption, one of them is in education. This study aims to provide training to kindergarten teachers on how to integrate anti-corruption values into teaching and learning activities using storytelling and game methods. This research applied mix method and took the setting in 2 schools in Salatiga, Indonesia. The qualitative data from the interviews were processed by transcribing the answers to the research questions, then sorting out the answers. The pre-test and post-test quantitative data were processed using Wilcoxon technique in SPSS. From the test it is known Asymp.Sig (2-tailed) is 0.011. Because the value of 0.011 is smaller than 0.05, it can be concluded that the hypothesis is accepted. This means that there is an increase in competence about Anti-Corruption Education before and after training using the module. This research also contributes to expanding literacy source for kindergarten teachers in the form of anti-corruption education training modules
Position-history and spin-history artifacts in fMRI time series

What is the impact of the spin history and position history on signal intensity after the alignment of acquired volumes? This question arises in many fMRI studies. We will focus on spin-history artefacts generated by the position-history of the scanned object. In fMRI an object is driven to steady state by applying a few dummy scans at the start of each measurement. A change in object position will disrupt the tissue's steady state magnetization. The disruption will propagate to the next few acquired volumes until a steady state is reached again. The variables which are involved in changing the longitudinal magnetization are: the shape and the position of the slice profiles, the times at which RF pulses occurred, the equilibrium magnetization map and the T1 map. Knowledge of these variables enables the prediction of those situations and the locations where the spin-history may compromise the fMRI analysis. In this paper we present a simulation of spin-history artefacts. The simulation shows that these effects, following a displacement, are similar to the transient period at the beginning of the measurement. Introducing gaps between the acquired slices increases these artefacts.
Design and analysis of small-area air trench bends and splitters

High efficiency small-area waveguide bends and splitters for perfluorocyclobutane (PFCB) copolymer materials have been designed with air trench structures (ATSs). An air trench at the intersection of one input and two output waveguides can function as a high efficiency splitter. High efficiency small-area waveguide bends are achieved by placing ATSs at the waveguide bend corners and operate through total internal reflection (TIR). In this paper we discuss bends and splitters that are designed specifically for constructing a ring resonator and a Mach-Zender interferometer. Two dimensional (2-D) finite difference time domain (FDTD) analysis has been used for design. In order to further examine the performance of realistic small-area air trench bend structures, we have also employed three dimensional (3-D) FDTD. From 3-D FDTD simulation results, we find that the 2-D designs are representative of actual devices. By combining small-area air trench bends and splitters, we show how a compact ring resonator can be realized. Simulation results show attractive properties for the proposed ring resonator design. Preliminary ATS etch results of PFCB with CO and O2 shows the possibility of fabricating the proposed devices.
The Numerical Simulation of non-Darcy Flow for YuShulin Low Permeability Oilfield

In this paper, a mathematical model for non-Darcy flow in low permeability oil reservoirs is developed, considering the threshold pressure gradient. The model is then discretized into difference equations and solved. FORTAN99 language is used to program the 3D three-phase numerical model for non-Darcy flow in the simulation software. FORTAN99 is used, because it is fast when performing huge engineering calculations. The pre and post processing system for the simulation software is developed using DELPHI language, because it has good interface with WINDOWS and has ability to manage databases. Numerical simulation is done in the simulation software combined with actual data from Yushulin low permeability oilfield. The effects of threshold pressure gradient, well spacing, and water injection modes are investigated. Results show that as the permeability increases from 1×10 -3 μm 2 to 12×10 -3 μm 2 , the sweep efficiency and the water displacement recovery also increases significantly. When the permeability of reservoir is fixed at 5×10 -3 μm 2 , the threshold pressure gradient increases as the well spacing decreases from 350m to 150m. Compared with the inverted nine spot water injection pattern, the sweep efficiencies for the line water injection pattern and the fivespot water injection pattern increase by 6.64% and 7.78%, respectively. The water displacement recoveries for them are increased by 2.94% and 3.57%, respectively.
Flow characteristics through porous bleed in supersonic turbulent boundary layers

Numerical simulations are conducted to characterize the flow for porous bleed in supersonic flow. Numerical solutions of the compressible Navier-Stokes equations are obtained in a domain that includes the bleed passages and plenum in addition to the external flow. The three-dimensional flow details within the bleed holes are presented and compared for single and multiple staggered bleed-hole arrangements. The results indicate that the flow within the bleed holes contain supersonic jets with embedded shocks along the bleed-hole back side and large separated flow regions in the front that grow with increased plenum pressures. The flow within the individual holes is shown to be influenced by the relative hole location in multiple-hole arrangements in addition to free-stream and plenum conditions. The computed results are compared to existing experimental data for the bleed sonic flow coefficient. The calculated boundary layer profiles downstream of the bleed region are compared to those obtained from two dimensional flow simulations with newly implemented bleed boundary condition in the Wind-US code are compared to those obtained in the fully resolved solution within the multiple bleed holes and plenum.