Tuning of the functional beamforming resolution for wind tunnel measurements

Conventional Frequency Domain Beamforming (CB) is characterised by the frequency dependency of the mainlobe width and by the presence of sidelobes that limit its dynamic range. Functional Beamforming (FB) has been introduced with the aim to overcome these limitations, narrowing the mainlobe and reducing the sidelobe levels. This paper introduces a strategy to obtain a beamformer with a target mainlobe width that is constant over a desired frequency range. The idea is to properly adjust the Functional Beamforming order ν, frequency by frequency, to preserve the mainlobe width. A tuning procedure of the order ν is presented and applied to a typical wind tunnel setup. A detailed analysis of the dependency “order ν versus frequency” is discussed and a general formula describing this dependency is provided. Finally, the effectiveness of the proposed approach is shown both on simulated and experimental test case

A comparison between aeroacoustic source mapping techniques for the characterisation of wind turbine blade models with microphone arrays

Characterising the aeroacoustic noise sources generated by a rotating wind turbine blade provides useful information for tackling noise reduction of this mechanical system. In this context, microphone array measurements and acoustic source mapping techniques are powerful tools for the identification of aeroacoustic noise sources. This paper discusses a series of acoustic mapping strategies that can be exploited in this kind of applications. A single-blade rotor was tested in a semi-anechoic chamber using a circular microphone array. The Virtual Rotating Array (VRA) approach, which transforms the signals acquired by the physical static array into signals of virtual microphones synchronously rotating with the blade, hence ensuring noise-source stationarity, was used to enable the use of frequency domain acoustic mapping techniques. A comparison among three different acoustic mapping methods is presented: Conventional Beamforming, CLEAN-SC and Covariance Matrix Fitting based on Iterative Re-weighted Least Squares and Bayesian approach. The latter demonstrated to provide the best results for the application and made it possible a detailed characterization of the noise sources generated by the rotating blade at different operating conditions

Ovulation induction in rabbit does submitted to artificial insemination by adding lecirelin to the semen dose: preliminary results

The aim of this study was to analyze the effect of intravaginal administration of lecirelin on ovulation induction in rabbit does. Eighty pluriparous does (Martini genetic strain) were submitted to AI using a seminal dose of 0.5 ml containing about 10 million sperms. To stimulate ovulation, 4 homogeneous groups were submitted to different treatments: Control Group: 0.2 ml intramuscular administration of lecirelin (Dalmarelin, Fatro\uae); 0.2 Group: 0.2 ml intravaginal administration of lecirelin; 0.6 Group: 0.6 ml intravaginal administration of lecirelin; 2.0 Group: 2 ml intravaginal administration of lecirelin. In groups receiving an intra-vaginal administration, 25 \ub5g/ml Dalmarelin was diluted in the seminal dose using benzilic alcohol (20 mg/ml) as excipient. Blood samples were collected from all females, to determine LH prior (-60, -30 and 0 minutes) and (30, 60, 90, 120 and 180 minutes) after AI, and progesterone once a week for 4 weeks. After 7 days from AI, 10 does per group were euthanized in order to analyze the ovarian status. The does of control group showed a high LH peak after 30 minutes from AI; whereas intra-vaginal administration of 0.2 and 0.6 ml determined a lower increase of LH blood concentration after 2 hours. The highest dose did not produce any LH or progesterone increase. The ovary status showed a higher number of corpora lutea in Control group (P<0.05), followed by 0.2 and 0.6 ones, whereas embryos were recorded only in Control and 0.2 groups. The unsuccessful of the other experimental groups could be ascribed to the negative effect of benzilic alcohol on seminal characteristic. Only 30% of 0.2 group does were pregnant and the prolificacy was 8 kits/doe. Compared to the control group, the progesterone concentration in pregnant does showed lower value in 0.2 group. In conclusion, in spite of the obtained results, it will be necessary to test different Dalmarelin formulations (lower volume, different excipient) to recommend the minimal dose to inject intravaginally for inducing ovulation

Investigation on intestinal bacterial flora and Salmonella spp. presence in organic and conventional chickens

The aim of this study was to evaluate the possible differences in the intestinal microflora composition among the different rearing systems (conventional vs organic) and the Salmonella diffusion using bacteriological techniques. The results showed that the differences between the two groups at the same age, expressed by the bacterial count, are not conclusive in showing an influence of the rearing systems. Salmonella Hadar was isolated once in caeca of conventional and once in caeca of organic ones. Though the results are preliminary and referred to a well defined geographic area in Central Italy, Salmonella detection does not seem to be common in conventional and organic chicken farms

From A to Z: Using Alphabet Books as an instructional Tool with Older Readers

Alphabet books provide a literature source for teachers to use in the classroom that focuses on a common sequence of textual organization which upper elementary and middle school students have known since they were young children. These students most likely had in their repertoire of beginning to read activities, alphabet books using common symbols to match the letters such as A is for apple, B is for bear, C is for cat. The objects were selected to match the true sound of the letter with a single or small number of illustrations to demonstrate the concept. The alphabet book addresses the 26 letters in picture book format with typically 24 to 48 pages, illustrations on double pages, and brief text (Kormanski and Stevens, 1993)

The AMS-02 Time of Flight System. Final Design

The AMS-02 detector is a superconducting magnetic spectrometer that will operate on the International Space Station. The time of flight (TOF) system of AMS-02 is composed by four scintillator planes with 8, 8, 10, 8 counters each, read at both ends by a total of 144 phototubes. This paper describes the new design, the expected performances, and shows preliminary results of the ion beam test carried on at CERN on October 2002.Comment: 4 pages, 6 EPS figures. Proc. of the 28th ICRC (2003

Comparative effectiveness of conservative and pharmacological interventions for chronic non-specific neck pain : Protocol of a systematic review and network meta-analysis

BACKGROUND: Neck Pain (NP) has been ranked as one of the top chronic pain conditions in terms of prevalence and years lived with disability in the latest Global Burden of Disease. NP has remarkable socio-economic consequences however, research efforts are limited. Discrepancies among guidelines recommendations on management of chronic neck pain exist. The purpose of this study protocol is to provide the methods for a review with network meta-analysis to identify the most effective interventions for chronic neck pain. METHODS: The following databases will be searched from their inception to February 2019: Cochrane Controlled Trials Register (CENTRAL), PubMed, CINAHL, Scopus, ISI Web of Science and PEDro.Randomized controlled trials (RCTs) on pharmacological and not pharmacological interventions will be included and their risk of bias will be evaluated using the Cochrane Risk of bias tool. Primary outcomes will be reduction in pain and disability. A network meta-analysis will be carried out and pairwise meta-analysis will be conducted using Stata 15 software. Grading of recommendations assessment, development, and evaluation (GRADE) will be applied to assess quality of the body of the evidence. RESULTS: The results of this review will be submitted to a peer-review journal for publication. CONCLUSION: This network meta-analysis will provide a comprehensive review on the most effective treatments for the management of chronic neck pain providing key evidence-based information to patients, clinicians and other relevant stakeholders. Registration: PROSPERO (registration number CRD42019124501)