Miracle-dz/UniFAR-FTUs huggingface dataset:
Frequency domain photoacoustics using intensity-modulated laser sources

In this paper, we present an overview of research in the area of narrow-bandwidth generation and detection of ultrasound using a technique referred to as frequency domain photoacoustics. An intensity-modulated continuous wave laser is used for narrowband ultrasound generation, and an interferometer coupled to a radio frequency lock-in amplifier is used for detection. Excellent sensitivity is achieved using sinusoidal modulation of the excitation laser over long time scales, thereby focusing the acoustic energy at the excitation frequency. We describe an experimental approach for the direct detection of narrowband signals at the ultrasound excitation frequency, and a superheterodyne technique in which the signal is optically down-converted to a low and fixed intermediate frequency prior to detection. Two approaches for materials characterisation using frequency domain photoacoustic measurements are presented. In the first approach, the modulation frequency of the excitation laser is scanned over the bandwidth of interest, and a transient sample response is constructed from the frequency-domain data. Ultrasound arrivals that are separated in the time domain can then be time gated for further analysis. In the second approach, the modulation frequency of the excitation laser is fixed, but the source-to-receiver distance is varied. The spatial frequencies of the ultrasound modes generated by the laser are detected by analysing the spatial variation of the phase, allowing for the velocity of each mode at a given frequency to be determined. Experimental measurements in thin films, plates and nanomechanical structures are presented.
Novel current-conveyor-based single-resistance-controlled/voltage-controlled oscillator employing grounded resistors and capacitors

A novel single-resistance-controlled/voltage-controlled oscillator using three current conveyors, two grounded capacitors and three grounded resistors is presented. The proposed circuit offers the following advantageous features: employment of three grounded resistors for ease of adjustment, independent oscillation control through a single grounded resistor, independent frequency control through a single grounded resistor, employment of two grounded capacitors ideal for integration, ease of convertibility into a voltage-controlled oscillator, and very good frequency stability.
Geosynthetic Tubes for Confining Pressurized Slurry: Some Design Aspects

This paper deals with geosynthetic tubes that are made of several geosynthetic sheets sewn together to form a shell capable of confining pressurized slurry. The slurry is sufficiently fluid so that it is possible to hydraulically fill the tube. After pumping the slurry in, the geosynthetic shell acts as a cheese cloth, allowing seepage of liquid out and retaining the solid particles. The availability of a wide selection of geosynthetics in terms of strength, durability, and permeability enables the use of hydraulically filled tubes in many applications, some of which may be considered critical (e.g., encapsulate contaminated soil). This paper presents an overview of an analysis to calculate both stresses in the geosynthetic and geometry of the tube. It also verifies the correctness and validity of the results obtained from a computer program developed to solve the problem. An instructive parametric study implies that the most critical factor needed to assure successful construction is the pumping pressure; a slight accidental increase in this pressure may result in a very significant stress increase in the encapsulating geosynthetic. Pressure increase beyond a certain level, however, has little influence on the storage capacity of the tube. Guidance in selecting an adequate geosynthetic, includingmore » partial safety factors and filtration properties, is also presented. Design aspects associated with required spacing of inlets and head loss of the slurry as it flows through the tube are considered outside the scope of this paper. « less
Aeroelastic control of a smart composite plate with delaminations

In this paper, aeroelastic performance of smart composite wing in the presence of delaminations is investigated. A control system is designed to enhance the dynamic stability of the delaminated composite wing. The refined higher order theory for analyzing an adaptive composite plate in the presence of delaminations is used. The theory accurately captures the transverse shear deformation through the thickness, which is important in anisotropic composites, particularly in the presence of discrete actuators and sensors and delaminations. The effects of delamination on the aeroelastic characteristics of composite plates are investigated. An active control system is designed to redistribute the loads and to minimize the effect of delamination. The pole placement technique is applied to design the closed loop system by utilizing piezoelectric actuators. Due to delamination, the significant changes in the natural frequencies of the lower modes are observed. And this causes the reduction on the flutter speed of the delaminated plate model. The aeroelastic control results show that controller makes the delaminated plate model behave like a normal plate. The controller also reduces a significant amount of RMS values of the gust response due to gust.
Retrospective Assessment of Escherichia coli Vaccination in Broiler Turkeys Under Field Conditions in 37 Farms from Brittany (France)

SUMMARY. Colibacillosis is a common bacterial disease in broiler production worldwide. It is emerging as a serious health concern in turkey production. Until recently, the disease was managed through antimicrobial therapy. However, such preventive strategies are no longer considered sustainable, and the advent of a live commercial vaccine registered for turkeys has modified health management plans in turkey production systems. In a French farming cooperative representing 10% of the country's turkey production, the vaccine was prescribed in two categories of farms: those with recurrent colibacillosis where an O78 Escherichia coli strain had been isolated, and those with sporadic outbreaks, where other serotypes had been documented. The commercial vaccine was administered in the first and third week of age. Performance data were collected retrospectively for all flocks produced over a 4-yr period from 37 turkey farm members of the cooperative. Segregated flocks from recurrent or sporadic farms, and whether or not vaccination had been performed, were analyzed and recorded. In farms with sporadic colibacillosis, vaccination significantly improved mortality rate and all performance parameters (average condemnation rate at the slaughterhouse, average feed conversion ratio, average weight per slaughtered turkey in each flock, average economic margin per flock, and performance index). Farms with recurrent outbreaks had comparable results, except for average flock mortality and condemnation rates, which were numerically reduced in vaccinated flocks compared to flocks that had not been vaccinated. This retrospective study contributes to the weight of evidence in favor of colibacillosis control through vaccination in turkey production.
The tail assignment problem with look-ahead maintenance constraints

The tail assignment problem is a critical part of the airline planning process that assigns specific aircraft to sequences of flights, called lines-of-flight, to be operated the next day. The aim of this paper is to develop an operationally flexible tail assignment that satisfies short-range---within the next three days---aircraft maintenance requirements and performs the aircraft/flight gate assignment for each input line-of-flight. While maintenance plans commonly span multiple days, the related tail assignment problems can be overly complex and provide little recourse in the event of schedule perturbations. The presented approach addresses operational uncertainty by extending the one-day routes aircraft maintenance routing approach to satisfy maintenance requirements explicitly for the current day and implicitly for the subsequent two days. A mathematical model is presented that integrates the gate assignment and maintenance planning problems. To increase the satisfaction of maintenance requirements, an iterative algorithm is developed that modifies the fixed lines-of-flight provided as input to the tail assignment problem. The tail assignment problem and iterative algorithm are demonstrated to effectively satisfy maintenance requirements within appropriate run times using input data collected from three different airlines.
Application of the mini AERCam free flyer for orbital inspection

The Engineering Directorate of NASA Johnson Space Center has developed a nanosatellite-class free-flyer intended for future external inspection and remote viewing of human spacecraft. The Miniature Autonomous Extravehicular Robotic Camera (Mini AERCam) technology demonstration unit has been integrated into the approximate form and function of a flight system. The spherical Mini AERCam free flyer is 7.5 inches in diameter and weighs approximately 10 pounds, yet it incorporates significant additional capabilities compared to the 35 pound, 14 inch AERCam Sprint that flew as a Shuttle flight experiment in 1997. Mini AERCam hosts a full suite of miniaturized avionics, instrumentation, communications, navigation, imaging, power, and propulsion subsystems, including two digital video cameras and a high resolution still image camera. The vehicle is designed for either remotely piloted operations or supervised autonomous operations including automatic stationkeeping and point-to-point maneuvering. Free-flyer testing has been conducted on an air-bearing table and in a six degree-of-freedom closed-loop orbital simulation. This paper describes recent enhancements to the Mini AERCam system aimed at providing a more autonomous system for space inspection, including docking mechanisms and on-board docking navigation for autonomous deployment and retrieval of the free flyer.
Roadmap for low-cost optical regeneration

Future transparent networks require optical regeneration. The regeneration process of amplitude-modulated signals consists of three key stages: re-amplification, re-shaping, and re-timing. In this Paper we briefly review various optical clock recovery methods and propose a polarization insensitive low-cost scheme capable of resolving timing information simultaneously for multiple wavelength channels. We also discuss the prospects of low-cost volume production with integrated optics and especially with Si-photonics.
Effect of temperature on the strength of a centrifugal compressor impeller for a turbocharger

High pressure ratio turbocharger technology is used to decrease fuel consumption, reduce emissions and improve power density of an internal combustion engine. The centrifugal compressor is the turbocharger’s core component. The reliability of its impeller becomes critical as the pressure ratio gets higher and the temperature starts playing an important role. In order to study the effect of the flow temperature on the reliability of a centrifugal compressor impeller, solid–fluid coupling is used to calculate the temperature distribution on the impeller surface. This temperature distribution is then applied as boundary condition in three-dimensional finite element analysis to analyze impeller stress. The results show that the percentage of impeller stress caused by thermal load remains approximately constant (about 2%) at different pressure ratios, which does not increase with increasing pressure ratio. Centrifugal load plays an absolutely critical role in the impeller stress at different pressure ratios. High pressure ratio also leads to an increase of air temperature, which causes higher material temperature and consequently the lower ultimate tensile strength of the impeller material. The maximum compressor pressure ratio which the impeller can bear decreases from 4.6 to 4.2 for the researched compressor if the effect of temperature on the ultimate tensile strength was considered. That means the effect of the temperature on compressor impeller strength and reliability at high pressure ratio should be considered while it can be ignored at low pressure ratio.
The Design and Simulation of Collision Avoidance System Based on Dual-Mode Collaborative

This article establish a model to give a detailed analysis of road vehicle collision avoidance systems according to the angle between vehicle and obstacle, and raise a vehicle collision avoidance detecting mechanism based on location mapping and distance detecting; furthermore, The authors combined this mechanism and BP artificial neural network to establish a new vehicle collision avoidance systems which is based on the collaboration between precise distance angle model and BP artificial neural network. We called this mechanism as BP artificial neural network vehicle collision avoidance model, the abbreviation is BP collision model. The convergence simulation of such model present that this model can resolve problem of collision avoidance and plan driving Path very well.
A Framework for Comparing IS Core Curriculum and IS Requirements for Accounting Majors

Core curriculum in information systems is of vital interest to the information systems community. Long scrutinized by the academic community and various stakeholders, the content of information systems core curriculum is once again a topic of debate. Accounting has undergone similar curriculum examination (including technology curriculum) amid criticisms for a variety of accounting failures in the 1990s. We map information systems core curriculum frameworks to accounting core curriculum frameworks for information systems courses and confirm the value of a core information systems curriculum for accounting majors. Using industry perspective as a focus, a pilot study in a graduate accounting information systems course identified information systems topics that are of distinct importance to managerial accountants as opposed to public accountants, suggesting different information systems curriculum needs within the major. This study resulted in the development of a three-dimensional modular information systems curriculum model mapping topical areas in information systems to specific major with Bloom's taxonomy represented on the third axis indicating how the learning takes place. Examination of information systems topics required by major within business may help confirm the identity of core concepts in information systems.
The role of dissent, conflict, and open dialogue in learning to live together harmoniously

Abstract “Learning To Live Together” (LTLT) has been proposed as one of the four UN pillars of education. Several Indian educationists including Aurobindo, Gandhi, Krishnamurti, and Tagore have emphasized equivalents like ‘education of the heart’ and founded schools that have pursued these goals, some for more than a century. This paper explores teachers’ perspectives on conflict, satyagraha/dissent, and dialogue and their role in education for LTLT. The paper draws upon a three year-long, multiple-embedded case-study that studied 14 teachers at five Indian schools founded or inspired by the educationists through ethnographic observations and interviews. The paper finds that LTLT should be perceived as a form of active harmony, which includes disagreements, dissent, and conflicts. The findings suggest that teachers differentiated conflicts from violence, perceived disagreements and conflicts as forms of pluralism, and created space for voicing dissent and resolving conflicts. They drew on dialogue, empathetic understanding, democratic decision-making, and social action to leverage dissent as a tool for building an equitable and engaged community.
Towards best management practices for implementing manufacturing flexibility

Purpose – The purpose of this research is to develop a framework and an initial list of best management practices for implementing manufacturing flexibility.Design/methodology/approach – To identify these practices, recent frameworks (i.e. 1988 and onward) for implementing manufacturing flexibility in organizations are reviewed. Based on this review, the major management practices for implementing flexibility are identified and synthesized into a new framework.Findings – This framework suggests that manufacturing flexibility should be implemented using a three‐stage approach, labeled: identifying required flexibility (i.e. identifying and justifying the flexibility types, measurements and tools needed to achieve the required manufacturing flexibility), achieving required flexibility (i.e. acquiring and implementing the organizational and technological tools needed to achieve the required manufacturing flexibility) and managing required flexibility (i.e. monitoring and changing the required flexibility typ.
Violence Detection in Ranches Using Computer Vision and Convolution Neural Network

This study engaged the convolutional neural network in curbing losses in terms of resources that farmers spends in treating animals where injuries must have emancipated from violence among other animals and in worst case scenario could eventually lead to death of animals. Animals in a ranch was the target and the study proposed a method that detects and reports activities of violence to ranchers such that farmers are relieved of the stress of close supervision and monitoring to avoid violence among animals. The scope of the study is limited to violence detection in cattle, goat, horse and sheep. Different machine learning models were built for each animal. The models yielded good results; the horse violence detection model had an outstanding performance of 93% accuracy, 93% accuracy for the sheep model, 88% accuracy for the goat model and 84% accuracy for the cattle model.
Streetcars and Recovery

Researching traditional streetcars’ development impacts is challenging: most U.S. lines operate in downtown areas with many development stimuli. This article addresses that challenge through analysis of New Orleans building permits after Hurricane Katrina. We estimate how post-Katrina permit frequency changes with distance from streetcar stops, controlling for damage, proximity to commercial areas, and pre-Katrina demographics. We find that distance to stops strongly predicts building permits. Residential permits increase with distance to stops; commercial permits decrease. Findings confirm streetcars support commercial development, yet suggest potential displacement of residential uses. Implications for future streetcar projects in New Orleans and elsewhere are discussed.
Advances in Non-Linear Apodization

Selected new methods and applications of non-linear apodization for irre gula rly-shaped and parse coherent apertures and arrays are presented. The benefits include unproved impulse response performance, i.e., reduced peak sidelobes and integrated sidelobe power, along with impr oved mainlobe res olution, compared to classic windowing techniques. Non-linear apodization (NLA) techniques can also strve as powerful engines for effective superresolution and bandwidth extrapolation of coherent data for filling spars e apertures. The sparse aperture filling property of superresolution algorithms for radar data forms the basis for a new concept which is introd uced here: Synthetic Multiple Aperture Radar Technology (SMART). Increased swath and/or reduced antenna size are some of the benefits postu lated for SMART applied to synthetic aperture radar (SAR) systems. The benefits of the se new methods and applications for non-linear apodization are then demonstrated for two specific applications: 1) sidelobe control for Y -type synthetic aperture radiometers, such as the European Soil Moisture and Ocean Salinity (SMOS) system [12] and JPL's propos ed GeoSTAR [13] concept; and, 2) ftlling of spa rse synthetic apertur e radar data by exploiting the band width extrapolation properties of non-linear apodization based superresolution techniques. The methods that have been developed and demonstrated herein have potential application to a wide range of passive and active microwave remote sensing and radar systems.
Adjuvant Whole Breast Radiotherapy Improve Survival in Women with Heart Failure with Reduced Ejection Fraction Receiving Breast-Conserving Surgery

Background: to date, no data on the effect of adjuvant whole breast radiotherapy (WBRT) on oncologic outcomes, such as all-cause death, locoregional recurrence (LRR), and distant metastasis (DM), are available in women with left-side breast invasive ductal carcinoma (IDC) and heart failure with reduced ejection fraction (HFrEF). Patients and Methods: we included 294 women with left-breast IDC at clinical stages IA–IIIC and HFrEF receiving breast-conserving surgery (BCS) followed by adjuvant WBRT or non-adjuvant WBRT. We categorized them into two groups based on their adjuvant WBRT status and compared their overall survival (OS), LRR, and DM outcomes. We calculated the propensity score and applied inverse probability of treatment weighting (IPTW) to create a pseudo-study cohort. Furthermore, we performed a multivariate analysis of the propensity score–weighted population to obtain hazard ratios (HRs). Results: in the IPTW-adjusted model, adjuvant WBRT (adjusted HR [aHR]: 0.60; 95% confidence interval [CI]: 0.44–0.94) was a significant independent prognostic factor for all-cause death (p = 0.0424), and the aHR (95% CI) of LRR and DM for adjuvant WBRT was 0.33 (0.24–0.71; p = 0.0017) and 0.37 (0.22–0.63; p = 0.0004), respectively, compared with the non-adjuvant WBRT group. Conclusion: Adjuvant WBRT was associated with a decrease in all-cause death, LRR, and DM in women with left IDC and HFrEF compared with non-adjuvant WBRT.
On-wafer high-frequency measurement improvements

As the size of advanced BJT or MOSFET devices shrink, very high frequency measurements are required to enable accurate circuit simulations. In order to conduct successfully high frequency measurements, efficient calibration and accurate de-embedding procedures must be followed as well as proper employment of the network analyzer. In this work, a new de-embedding procedure which takes into account propagation effects is proposed. Results are presented and compared to those obtained with other techniques. Errors due to an improper use of the network analyzer are also looked into and, subsequently, a general solution scheme is given. <<ETX>>
PFC Bridge Converter for Voltage-controlled Adjustable-speed PMBLDCM Drive

In this paper, a buck DC-DC bridge converter is used as a power factor correction (PFC) converter for feeding a voltage source inverter (VSI) based permanent magnet brushless DC motor (PMBLDCM) drive. The front end of the PFC converter is a diode bridge rectifier (DBR) fed from single phase AC mains. The PMBLDCM is used to drive the compressor of an air conditioner through a three-phase voltage source inverter (VSI) fed from a variable voltage DC link. The speed of the air conditioner is controlled to conserve energy using a new concept of voltage control at a DC link proportional to the desired speed of the PMBLDC motor. Therefore, VSI operates only as an electronic commutator of the PMBLDCM. The current of the PMBLDCM is controlled by setting the reference voltage at the DC link as a ramp. The proposed PMBLDCM drive with voltage control-based PFC converter was designed and modeled. The performance is simulated in Matlab-Simulink environment for an air conditioner compressor load driven through a 3.75 ㎾, 1500 rpm PMBLDC motor. To validate the effectiveness of the proposed speed control scheme, the evaluation results demonstrate improved efficiency of the complete drive with the PFC feature in a wide range of speed and input AC voltage.