Miracle-dz/UniFAR-FTUs huggingface dataset:
Mechanism of bandwidth improvement in passively cooled SMA position actuators

The heating of shape memory alloy (SMA) materials leads to a thermally driven phase change which can be used to do work. An SMA wire can be thermally cycled by controlling electric current through the wire, creating an electro-mechanical actuator. Such actuators are typically heated electrically and cooled through convection. The thermal time constants and lack of active cooling limit the operating frequencies. In this work, the bandwidth of a still-air-cooled SMA wire controlled with a PID controller is improved through optimization of the controller gains. Results confirm that optimization can improve the ability of the actuator to operate at a given frequency. Overshoot is observed in the optimal controllers at low frequencies. This is a result of hysteresis in the wire’s contraction–temperature characteristic, since different input temperatures can achieve the same output value. The optimal controllers generate overshoot during heating, in order to cause the system to operate at a point on the hysteresis curve where faster cooling can be achieved. The optimization results in a controller which effectively takes advantage of the multi-valued nature of the hysteresis to improve performance.
Redesign of Ultrasonic Block Horns for Improved Vibration Performance

Ultrasonic block horns are prone to reliability problems associated with modal activity close to the tuned operating frequency. This paper presents an approach to block horn design, which relies on two laser based vibration measurement techniques, electronic speckle pattern interferometry (ESPI) and laser doppler velocimetry (LDV) modal analysis, to validate finite element (FE) models. Block horn vibration characteristics are interpreted from experimental and theoretical data such that successful horn redesign can be achieved from modifications to the FE models.
Research on the International Space Station - An Overview

The International Space Station (ISS) celebrates ten years of operations in 2008. While the station did not support permanent human crews during the first two years of operations November 1998 to November 2000 it hosted a few early science experiments months before the first international crew took up residence. Since that time and simultaneous with the complicated task of ISS construction and overcoming impacts from the tragic Columbia accident science returns from the ISS have been growing at a steady pace. As of this writing, over 162 experiments have been operated on the ISS, supporting research for hundreds of ground-based investigators from the U.S. and international partners. This report summarizes the experimental results collected to date. Today, NASA's priorities for research aboard the ISS center on understanding human health during long-duration missions, researching effective countermeasures for long-duration crewmembers, and researching and testing new technologies that can be used for future exploration crews and spacecraft. Through the U.S. National Laboratory designation, the ISS is also a platform available to other government agencies. Research on ISS supports new understandings, methods or applications relevant to life on Earth, such as understanding effective protocols to protect against loss of bone density or better methods for producing stronger metal alloys. Experiment results have already been used in applications as diverse as the manufacture of solar cell and insulation materials for new spacecraft and the verification of complex numerical models for behavior of fluids in fuel tanks. A synoptic publication of these results will be forthcoming in 2009. At the 10-year point, the scientific returns from ISS should increase at a rapid pace. During the 2008 calendar year, the laboratory space and research facilities were tripled with the addition of ESA's Columbus and JAXA's Kibo scientific modules joining NASA's Destiny Laboratory. All three laboratories, together with external payload accommodations, support a wide variety of research racks and science and technology experiments. In 2009, the number of crewmembers will increase from three to six, greatly increasing the time available for research. The realization of the international scientific partnership provides new opportunities for scientific collaboration and broadens the research potential on the ISS. Engineers and scientists from around the world are working together to refine their operational relationships and build from their experiences conducting early science to ensure maximum utilization of the expanded capabilities aboard ISS. This paper will summarize science results and accomplishments, and discuss how the early science utilization provides the foundation for continuing research campaigns aboard the ISS that will benefit future exploration programs.
Pedagogical Models to Implement Effective STEM Research Experience Programs in High School Students

High school research experience programs (HSREPs) provide opportunities for true science education and expose students to scientific investigations in laboratory settings. Various HSREPs models have been practiced to shape students’ research understandings; however, a systematic comparison of the success, challenges, and opportunities of these HSREPs has not been gauged. This article compares the effectiveness of such science, technology, engineering, and mathematics (STEM) based HSREP models reported in the last two decades. We shortlisted seventeen studies on the most effective HSREPs and identified the characteristics of these reports. Results show that student research experiences vary depending on the structure of the model used and the nature of the laboratory setting to which students are exposed. However, there is a dire need to integrate more collaborative and customized research practices to accommodate more students in HSREPs. Additionally, intensive support, mentoring, and coaching are essential to provide students a comprehensive understanding to excel in their research career pathway. Finally, there is a desperate need for further studies to develop the frameworks that can help the smooth transition of high school students into research-oriented university programs.
Fall Detection on a single Doppler Radar Sensor by using Convolutional Neural Networks

Falls are a major public health concern and the leading cause of accidental deaths among elders. Technologies capable of fast and accurate fall detection are crucial to provide immediate assistance and reduce complications associated with a fall. This article presents a new deep-learning approach for automated fall detection from signatures of a continuous-wave micro-Doppler radar. Unlike related methods, the proposed approach applies convolutional neural networks directly to raw time-frequency spectrograms to identify falls. It allows CNN to learn the fall features and classification boundaries without employing additional hardware or large data sets to distinguish abrupt and slow falls from non-fall actions. Experiments show that the approach achieves the fall classification accuracy of 95%.
Design of Dielectric Resonator antenna with band notched Characteristics for UWB applications

In this paper, the design of dielectric resonator antenna with elliptical patch and dual band notched characteristics for UWB applications is proposed. The size of the antenna is 40x40x1.6 mm3.The CPW ground plane of this antenna is like a half circle. The antenna consists of elliptical shape radiating patch with 50Ω transmission line. Two U- slots are inserted in the middle of the elliptical patch to achieve the dual band notched characteristics. The centre frequencies of two notched bands can be adjusted by modifying the length and width of inserted U slots. The proposed ultra-wideband (UWB) antenna is optimized to operate in the frequency range from 3 to 11 GHz for VSWR < 2.Good agreement is achieved between the simulated and measured results. These results also show good performances in terms of antenna gain and radiation patterns. With these features, this antenna is expected to be good candidate in various UWB systems.
Research on Image Binding Mechanism Based on Kinect Skeletal Tracking in Virtual Fitting System

On the basis of kinect skeleton track data module, proposing a skeleton track-bound algorithm, you can implement static clothing pictures real time interaction with dynamic characters, combined with WPF in Visual Studio 2010, the corresponding hardware and software resources, a set of accessible and language programming in c# virtual fitting system. Kinect human key joint points coordinates of the corresponding parameter, a corresponding operation, bound to the clothes in the image, makes the image size can be based on different size fitting character change, achieving the desired effect of fitting.
Downstream drifting of Macrobrachium (Decapoda: Palaemonidae) larvae in the Shimanto River, Japan

: This study was undertaken to clarify the downstream drifting of Macrobrachium larvae in the Shimanto River by 24-hour sampling. Stage I zoeae accounted for most larvae collected in fresh and brackish waters. M. formosense and M. japonicum dominated in brackish and fresh waters, respectively, while M. nipponense occurred only in brackish waters. The amount of yolk droplets of M. formosense and M. japonicum reduced over time in freshwater. However, no larvae that had completely used up their yolks were observed. Even though M. japonicum larvae drifted from farther upstream than those of M. formosense , they had a higher residual amount of yolk droplets. Therefore, long-distance and long-time drifting in M. japonicum may be enabled by delaying the absorption rate of droplets.
Fault diagnosis of WSNs node based on wavelet neural network

Purpose – The purpose of this paper is to provide a new method of the fault diagnosis of wireless sensor networks (WSNs) node, which is based on wavelet neural network (WNN). Design/methodology/approach – The approach uses WNN to diagnose the sensor module of the node.Findings – The method based on WNN sensing parts of the WSN nodes in additional fault location is accurate feasible.Research limitations/implications – The fault of WSNs node protean, it is necessary to establish even more fault model for the training of WNN.Practical implications – The simulation results provide useful guidelines for the engineers faced with the detection the fault of the WSN node.Originality/value – The WNN is well‐known. The innovation here is applying this method in order to diagnose the fault of WSNs node.
A 3-D analytic eddy current model for a finite width conductive plate

Purpose – A 3-D analytic modeling technique for calculating the eddy current distribution, force and power loss in a conductive plate of finite width and thickness is presented. The derived equations are expressed in a general form so that any magnetic source can be utilized. The model assumes the length of the conductive plate is large and the thickness of the plate is thin but not negligible. The paper aims to discuss these issues. Design/methodology/approach – The conducting and non-conducting regions are formulated in terms of decoupled magnetic vector potential components. In order to accurately compute the eddy current fields and forces the source field only needs to be applied on the surface of the conducting plate. The primary focus is on reducing the eddy current computational time. Findings – The accuracy of the presented approach is verified by utilizing a magnetic rotor that has both a rotational and translational motion. The proposed method is computationally efficient and its accuracy is val.
Is Zero Tolerance an Optimal Weed Management Strategy? The Economic Threshold Revisited

Economic thresholds (ET) were originally developed and applied to insect management during the 1970s. Traditional ET methodologies have sporadic success in weed management scenarios and are not globally appropriate for weed management especially in presence of herbicide resistant species. Historically, the economic threshold equation has been static and myopic, ignoring any multiple-period impact or the soil seed bank. The evolution of herbicide resistant weed species has prompted scientists to reconsider economic thresholds for weed management; and intuitively have chosen zero-tolerance for potentially herbicide-resistant weed species. The weed science and economics literature addressing resistant weed management supports zero-tolerance, especially when dynamic optimization techniques were applied to the problem. Although dynamic programming techniques do not equate to zero-tolerance recommendations, single-period static cost-benefit analyses tend to support non-zero economic thresholds in scenarios where zero-tolerance was the optimum strategy. The objectives were to present an ET model suitable for accurately modeling weed control strategies with herbicide resistant species. Preliminary results suggest the multiple-season dynamic framework is the best management practice for weed management.
Temporal and Quantitative Analysis of Aortic Immunopathologies in Elastase-Induced Mouse Abdominal Aortic Aneurysms

Objective Elastase-induced abdominal aortic aneurysm (AAA) model is widely used for aneurysmal pathogenesis and translational research. However, temporal alternations in aneurysmal histologies remain unknown. This study is aimed at analyzing temporal immunopathologies of aneurysmal aorta following experimental AAA induction. Methods Male C57BL/6J mice at the age of 10-14 weeks received intra-aortic infusion of elastase to induce AAAs. Aortic diameters at the baseline and indicated days after AAA induction were measured, and aortae were collected for histopathological analysis. Results Aorta diameters increased from 0.52 mm at the baseline levels to 0.99 mm, 1.34 mm, and 1.41 mm at days 7, 14, and 28, respectively, corresponding 90%, 158%, and 171% increases over the baseline level. Average aortic diameters did not differ between days 14 and 28. Severe elastin degradation and smooth muscle cell depletion were found at days 14 and 28 as compared to the baseline and day 7. No difference in the scores of medial elastin and SMC destruction was noted between days 14 and 28. Consistent results were found for leukocyte accumulation, neoangiogenesis, and matrix metalloproteinase expression. Twenty-eight days after AAA induction, all aneurysmal pathologies showed an attenuated trend, although most histopathological parameters did no differ between days 14 and 28. Conclusion Our data suggest that almost aneurysmal immunohistopathologies reach maximal 14 days following AAA induction. Analysis of day 14 histologies is sufficient for AAA pathogenesis and translational studies in elastase-induced mouse experimental AAAs.
The effect of clamping sequence on dimensional variability in sheet metal assembly

Finite element (FE) modelling techniques have become a popular tool for exploring welding and clamping sequence dependence in sheet metal assemblies. In the current paper, the dimensional variability associated with different assembly clamping sequences is investigated with a FE contact modelling approach implemented in the commercial code Abaqus. A simplified channel section assembly consisting of a top hat and bottom plate is the case study investigated. Expected variation modes of bow and twist were used to simulate key variability sources in the main structural component under investigation; the top hat of the channel section. It was found that final assembly variability can change considerably depending on clamp sequence selection. It was also found that different clamp sequences can control particular modes of variation better than others, and that there is not one particular clamping sequence that is the best for containing all variation modes. An adaptable assembly process is therefore suggested, where given the shape of input components the best available clamping sequence is selected. Comparison of the performance of the proposed adaptable clamping sequence to traditional fixed clamping sequences shows improvements for the dimensional control of variability in non-rigid components. While introducing such a method in production would require inspection of each component being assembled and investigation of the alternative clamping sequences, given access to fast and detailed dimensional inspection technology such as optical coordinate measuring machines (OCMM's), the approach shows promise for future application.
Assessing Risks to Inform Resilience: a Criticality Assessment of the British Railway Network

National infrastructures are constantly at risk from extreme weather events and random shocks that induce widespread failures across such systems. For example, the vulnerability of Britain’s national-scale rail infrastructure has been highlighted during extreme floods, and it seems likely that the levels of risk faced by transport infrastructures more generally will increase in future years. Given the importance of rail infrastructure, there is a clear need for an improved understanding of the risks which it faces. Such a risk assessment would aim to identify the relative criticality of the network elements which different risk events are likely to affect, leading towards better risk management and resilience investment decisions. This paper provides a methodology to meet this need, by analysing the systemic risk to Britain’s rail infrastructure from a range of disruptive events. It first considers the range of events and processes which have the potential to disrupt operation of the rail network. Alongside this, a procedure is developed for assessing the relative criticality of different nodes and edges on the network based on the passenger traffic they carry. Two case study risk types (floods and traction system failures) are used to demonstrate how criticality assessment can identify those parts of the rail network which are most at risk of causing substantial disruption to rail traffic, and therefore are most critical to maintaining national mobility. The paper concludes by considering the implications of this analysis for investment decisions and the potential for transferring this methodology to other spatial or economic contexts.
Compact, Slotted, Printed Antennas for Dual-Band Communication in Future Wireless Sensor Networks

Inverted-F antennas (IFAs) are a primary choice to implement the radiating system of portable devices. A tried and tested idea can remain topical if proven useful in modern applications. This paper shows that printed IFAs (PIFAs) are capable of forming robust, compact, dual-band radiating systems for wireless microsensors with an adjustable spacing between bands. Reactive tuning was applied by inductively loading the structures with prefractal slots; inductive slot loading degenerates higher-order resonances and increases the fractional bandwidth (FBW). The current distributions revealed that most of the element area is used for radiation at both resonances. In radiation terms, the antennas provide satisfactory gains and high efficiencies (≥82%). A simple figure of merit is used to compare the performance of the three PIFAs head to head. Operation at 2.5 GHz and 5.5 GHz indicated that changes in slot geometry almost double the FBW. The proposed antennas serve both the 5.15–5.35 GHz U-NII and the 5.8 GHz ISM bands; at the lower band, their size is less or equal to the half-wavelength dipole. This study of dual-band antennas also showed that the aggregate FBW of a PIFA is bounded; by degenerating higher-order modes, the designer redistributes whatever bandwidth is available by the antenna itself to the desired bands.
The pleiotropic functions of intracellular hydrophobins in aerial hyphae and fungal spores

Higher fungi can rapidly produce large numbers of spores suitable for aerial dispersal. The efficiency of the dispersal and spore resilience to abiotic stresses correlate with their hydrophobicity provided by the unique amphiphilic and superior surface-active proteins–hydrophobins (HFBs)–that self-assemble at hydrophobic/hydrophilic interfaces and thus modulate surface properties. Using the HFB-enriched mold Trichoderma (Hypocreales, Ascomycota) and the HFB-free yeast Pichia pastoris (Saccharomycetales, Ascomycota), we revealed that the rapid release of HFBs by aerial hyphae shortly prior to conidiation is associated with their intracellular accumulation in vacuoles and/or lipid-enriched organelles. The occasional internalization of the latter organelles in vacuoles can provide the hydrophobic/hydrophilic interface for the assembly of HFB layers and thus result in the formation of HFB-enriched vesicles and vacuolar multicisternal structures (VMSs) putatively lined up by HFBs. These HFB-enriched vesicles and VMSs can become fused in large tonoplast-like organelles or move to the periplasm for secretion. The tonoplast-like structures can contribute to the maintenance of turgor pressure in aerial hyphae supporting the erection of sporogenic structures (e.g., conidiophores) and provide intracellular force to squeeze out HFB-enriched vesicles and VMSs from the periplasm through the cell wall. We also show that the secretion of HFBs occurs prior to the conidiation and reveal that the even spore coating of HFBs deposited in the extracellular matrix requires microscopic water droplets that can be either guttated by the hyphae or obtained from the environment. Furthermore, we demonstrate that at least one HFB, HFB4 in T. guizhouense, is produced and secreted by wetted spores. We show that this protein possibly controls spore dormancy and contributes to the water sensing mechanism required for the detection of germination conditions. Thus, intracellular HFBs have a range of pleiotropic functions in aerial hyphae and spores and are essential for fungal development and fitness.
Tutorial review Trends in current conveyor and current-mode amplifier design

A current-mode approach, involving current conveyor and current-mode amplifiers, is playing an increasingly important role in the development of many new high-performance circuits for signal processing applications. This paper will review the recent trends that have emerged over the last two years in certain areas of current-mode design, with particular attention to current conveyors and amplifiers.
Blind Restoration of Linearly Degraded

This paper addresses the problem of simultaneous parameter estimation and restoration of discrete-valued signals that are blurred by an unknown FIR filter and contaminated by additive Gaussian white noise with unknown variance. Assuming that the signals are stationary Markov chains with known state space but unknown initial and transition probabilities, Bayesian inference of all unknown quantities is made from the blurred and noisy observations. A Monte Carlo procedure, called the Gibbs sampler, is employed to calculate the Bayesian estimates. Simulation results are presented to demonstrate the effectiveness of the method.
The use of strain gauges in vibration-based damage detection

Strain gauges and strain measurements have been widely used in structural health monitoring (SHM) systems as a means of detecting and localizing damage, due to their higher sensitivity to local damage. These damage identification techniques normally use strain related measurements such as the mode curvature, strain frequency response function or strain energy as the main parameter to detect damage. However, damage detection techniques based on acceleration measurements have also been investigated in the past, using modal parameter comparison and other methodologies. In this paper, the use of vibration-based strain measurements for use in SHM systems will be evaluated, with the purpose of characterizing their higher sensitivity in damage detection, when compared to other vibration measurements, such as acceleration-based measurements. Since the choice and use of the most damage sensitive parameter can lead to a more sensitive and robust system, the assessment of the more suitable sensor and processing of information is very important. For this purpose, numerical and experimental examples will be discussed to evaluate the higher performance of the strain gauges.