Intensity Probe Research Articles

The effects of acoustical ceiling panel type and penetrations forservices on vertical sound isolation inside buildings

Attenuation of sound transmitting between rooms oriented over one another inside buildings is studied. Transmission loss and sound transmission class were measured by an independent, accredited, acoustics laboratory with and without a variety of modular acoustic ceilings suspended under a baseline concrete floor structure. Ceiling panel material types include stone wool, fiberglass and mineral fiber. Ceilings were tested with and without the presence of service penetrations for supply air diffusers, return air grilles and light fixtures. Some ceilings were also scanned with a sound intensity probe and the resulting color sound maps are used as supplemental method of evaluating both isolation and absorption performance of the individual components of the ceiling systems. Results show that while the effects of ceiling panel type on absorption performance, and thus room acoustics, is substantial, the material type and weight of the ceiling panels do not substantially affect the overall isolation performance of the floor-ceiling assembly.

Helicopter Inside Cabin Acoustic Evaluation: A Case Study-IAR PUMA 330.

This paper presents an inside-cabin acoustic evaluation of the IAR PUMA 330 helicopter, manufactured by IAR S.A. Brasov. In this study, based on the acoustic assessment inside the helicopter, areas with high noise levels are identified. In this regard, several tests were carried out in accordance with the ISO 5129 standard. In the first stage of the assessment, a measurement campaign was performed to identify the acoustic leaks from the outside noise sources propagating inside the cabin (in the door area) and the acoustic attenuation of the helicopter structure. These tests were performed on the factory runway, with the helicopter in parked position (ground tests). During the ground tests, the helicopter engines were turned off. The tests consisted of placing two loudspeakers directed towards the helicopter door and generating pink noise. Inside the helicopter, the entire door frame opening was scanned with an intensity probe to identify acoustic leaks areas. The second assessment stage was to determine the areas of the cabin with the highest levels of noise. Within the measurement campaign, 16 microphones were placed inside the cabin, at the level of the passengers’ heads, arranged in seven zones. The tests were carried out with the helicopter engines started, staying at fixed point above the ground (hovering), and then a flight test, in which all the maneuvers necessary for the use of the helicopter were performed (in-flight tests). Based on the measurement results, it was possible to highlight the noise spectral components in each of the seven areas. The noise assessment revealed high noise levels inside the cabin, having as main noise sources the transmission gear and the door area, leading to the need for reducing the noise exposure for passengers and crew, thus the need to reduce noise levels inside the helicopter.

MEMS microphone intensity array for cabin noise measurements

Aircraft cabin noise measurements in flight are used toto quantify the noise level, and to identify the entry point of acoustic energy into the cabin. Sound intensity probes are the state-of-the-art measurement technique for this task. During measurements, additional sound absorbing material is used to ease the rather harsh acoustic measurement environment inside the cabin. In order to decrease the expensive in-flight measurement time, an intensity array approach was chosen. This intensity probe consists of 512 MEMS-Microphones. Depending on the frequency, these microphones can be combined as an array of hundreds of 3D- intensity probes. The acoustic velocity is estimated using a high order 3D finite difference stencil. At low frequencies, a larger spacing is used to reduce the requirement of accurate phase match of the microphone sensors. Measurements were conducted in the ground-based Dornier 728 cabin noise simulation as well as in-flight.

The effects of acoustical ceiling panel type and penetrations for services on vertical sound isolation inside buildings

Attenuation of sound transmitting between rooms oriented over one another inside buildings is studied. Transmission loss and sound transmission class were measured by an independent, accredited, acoustics laboratory with and without a variety of modular acoustic ceilings suspended under a baseline concrete floor structure. Ceiling panel material types include stone wool, fiberglass and mineral fiber. Ceilings were tested with and without the presence of service penetrations for supply air diffusers, return air grilles and light fixtures. Some ceilings were also scanned with a sound intensity probe and the resulting color sound maps are used as a supplemental method of evaluating both isolation and absorption performance of the individual components of the ceiling systems. Results show that while the effects of ceiling panel type on absorption performance, and thus room acoustics, is substantial, the material type and weight of the ceiling panels do not substantially affect the overall isolation performance of the floor-ceiling assembly.

The Implications of Endoplasmic Reticulum Stress Response in the Prognosis and Pathogenesis of Myelodysplastic Syndrome

Background and PurposeMyelodysplastic syndrome (MDS) is a group of heterogeneous disorders characterized by ineffective hematopoiesis and risk of leukemia transformation. The exact pathophysiology of MDS remains incompletely defined. Endoplasmic reticulum (ER) stress response is induced when environmental stimuli and metabolic changes of cells cause derangement of normal ER functions and accumulation of unfolded proteins within it. ER stress response has been shown to be activated in many types of cancer including leukemia. Its activation is thought to confer survival benefit to cancer cells and is related to resistance to anticancer therapies. However, whether ER stress response plays a role in the pathogenesis or affects the clinical and genetic presentations of MDS is still unknown.Material and MethodsA total of 176 adult patients with newly diagnosed primary MDS at the National Taiwan University Hospital and 20 healthy marrow donors who had enough cryopreserved bone marrow cells and complete clinical and genetic information for analysis were enrolled. Diagnosis and classification of MDS were made according to the WHO 2008 classification. We used Affymetrix Human Transcriptome Array 2.0 array of RNA to profile the global gene expression. The probe intensity data (CEL files) and probe set summarization files (CHP files) were generated and analyzed by Affymetrix GeneChip Command Console (AGCC) and Transcriptome Analysis Console (TAC) software. We used the Gene Set Enrichment Analysis (GSEA) tool to comprehensively test the roles of the ER stress pathways in MDS.ResultsAmong the 176 MDS patients, 42 had refractory cytopenia with unilineage dysplasia (RCUD, 23.9%), 13 refractory anemia with ring sideroblasts (RARS, 7.4%), 36 refractory cytopenia with multilineage dysplasia (RCMD, 20.5%), 9 refractory cytopenia with multilineage dysplasia and ringed sideroblasts (RCMD-RS, 5.1%), 32 refractory anemia with excess blasts-1 (RAEB1, 18.2%), and 44 refractory anemia with excess blasts-2 (RAEB2, 25.0%). Patients with each subtype of MDS had significantly different expression in more than 8000 probe sets of coding genes compared with healthy donors. In contrast, the differences were much less remarkable among the subgroups of MDS, implying a common theme of global gene expression profile among subtypes of MDS and an intrinsic genetic difference between MDS and normal controls. The differentially expressed probe sets between MDS patients and healthy donors were explored by database search and literature review. Among the perturbed biological pathways, we focused on the ER stress response for further study. GSEA revealed a significant dysregulation of ER stress-associated genes in MDS (GSEA enrichment score=0.58; P=0.035; Figure 1), indicating a crucial role of ER stress in the pathogenesis of MDS. We noted 17 genes which were up-regulated in MDS patients in our array data, including BAG5, ATG17, BECN1, CALR, CANX, TRAF2, EIF2S1, PKR, SIAH1, SIAH2, S1P, S2P, EDEM3, PDIA6, GRP94, AMPK, and XBP-1 . On the contrary, GADD34, which inhibits ER stress response, was down-regulated in the MDS patients.By univariate analysis, 10 (BAG5, CALR, CANX, GRP94, EDEM3, PDIA6, SIAH1, S1P, S2P, and XBP1) of the 17 up-regulated genes in MDS patients were associated with shorter overall survival, and 7 (CALR, CANX, S2P, EDEM3, PDIA6, XBP1, and TRAF2)of them were associated with shorter time to leukemia transformation (all with P<0.05). We used the sum of the expression levels of the five genes with the strongest associations with shorter overall survival, BAG5, CALR, PDIA6, EDEM3, and XBP1 (Figure 2), to establish an “ER stress score”. Higher ER stress score was associated with shorter overall survival (Hazard ratio = 2.208, P= 0.003) and shorter time to leukemia transformation (Hazard ratio = 3.176, P= 0.004) in multivariate analysis independent of other well known prognostic factors. (Figure 3A, 3B, and Table 1). The prognostic significance of the score was also confirmed in another 31 MDS patients. (P=0.046, Figure 3C)ConclusionSeveral important genes related to the ER stress response have higher expression levels in MDS patients compared with healthy donors and their up-regulations are associated with shorter overall survival and time to leukemia transformation. This finding indicated that deregulation of ER stress response can predict MDS prognosis and it may be involved in the pathogenesis of MDS. [Display omitted] DisclosuresTang:Celgene International Sàrl: Research Funding. Yao:Celgene International Sàrl: Research Funding. Li:Celgene International Sàrl: Research Funding. Huang:Celgene International Sàrl: Research Funding. Chen:Celgene International Sàrl: Research Funding. Ko:Celgene International Sàrl: Research Funding. Hsu:Celgene International Sàrl: Research Funding. Wu:Celgene International Sàrl: Research Funding. Lin:Celgene International Sàrl: Research Funding. Tsai:Celgene International Sàrl: Research Funding. Tien:Celgene International Sàrl: Research Funding.

H i intensity mapping with MeerKAT: calibration pipeline for multidish autocorrelation observations

ABSTRACT While most purpose-built 21-cm intensity mapping experiments are close-packed interferometer arrays, general-purpose dish arrays should also be capable of measuring the cosmological 21-cm signal. This can be achieved most efficiently if the array is used as a collection of scanning autocorrelation dishes rather than as an interferometer. As a first step towards demonstrating the feasibility of this observing strategy, we show that we are able to successfully calibrate dual-polarization autocorrelation data from 64 MeerKAT dishes in the L band (856–1712 MHz, 4096 channels), with 10.5 h of data retained from six nights of observing. We describe our calibration pipeline, which is based on multilevel radio frequency interference flagging, periodic noise diode injection to stabilize gain drifts, and an absolute calibration based on a multicomponent sky model. We show that it is sufficiently accurate to recover maps of diffuse celestial emission and point sources over a 10° × 30° patch of the sky overlapping with the WiggleZ 11-h field. The reconstructed maps have a good level of consistency between per-dish maps and external data sets, with the estimated thermal noise limited to 1.4 × the theoretical noise level (∼2 mK). The residual maps have rms amplitudes below 0.1 K, corresponding to $\lt 1{{\ \rm per\ cent}}$ of the model temperature. The reconstructed Galactic H i intensity map shows excellent agreement with the Effelsberg–Bonn H i Survey, and the flux of the radio galaxy 4C + 03.18 is recovered to within 3.6 per cent, which demonstrates that the autocorrelation can be successfully calibrated to give the zero-spacing flux and potentially help in the imaging of MeerKAT interferometric data. Our results provide a positive indication towards the feasibility of using MeerKAT and the future Square Kilometre Array to measure the H i intensity mapping signal and probe cosmology on degree scales and above.

Anomalous light-induced broadening of the spin-noise resonance in cesium vapor

We uncover a highly nontrivial dependence of the spin-noise (SN) resonance broadening induced by the intense probe beam. The measurements were performed by probing the cell with cesium vapor at the wavelengths of the transition $6^{2}S_{1/2}\ensuremath{\leftrightarrow}6^{2}P_{3/2}$ (${D}_{2}$ line) with the unresolved hyperfine structure of the excited state. The light-induced broadening of the SN resonance was found to differ strongly at different slopes of the ${D}_{2}$ line and, generally, varied nonmonotonically with light power. We discuss the effect in terms of the phenomenological Bloch equations for the spin fluctuations and demonstrate that the SN broadening behavior strongly depends on the relation between the pumping and excited-level decay rates, the spin precession, and decoherence rates. To reconcile the puzzling experimental results, we propose that the degree of optical perturbation of the spin system is controlled by the route of the excited-state relaxation of the atom or, in other words, that the act of optical excitation of the atom does not necessarily break down completely its ground-state coherence and continuity of the spin precession. Spectral asymmetry of the effect, in this case, is provided by the position of the ``closed'' transition $F=4\ensuremath{\leftrightarrow}{F}^{\ensuremath{'}}=5$ at the short-wavelength side of the line. This hypothesis, however, remains to be proven by microscopic calculations.

Selective monitoring of noise emitted by vehicles involved in road traffic

An acoustic intensity probe was developed measures the sound intensity in three orthogonal directions, making possible to calculate the azimuth and elevation angles, describing the sound source position. The acoustic sensor is made in the form of a cube with a side of 10 mm, on the inner surfaces of which the digital MEMS microphones are mounted. The algorithm works in two stages. The first stage is based on the analysis of sound intensity signals, and it detects acoustic events. The second stage analyses a detection function based on the normalized source position; its task is to determine whether the acoustic event represents a vehicle passing the sensor and detecting its movement direction. The acoustic probes were mounted inside intelligent lamps that illuminate the roadways depending on the volume of traffic. The paper explains how accurately traffic can be monitored through directional noise analysis and shows the resulting application to smart cities. [The project has been subsidized by the Polish National Centre for Research and Development (NCBR) from the European Regional Development Fund No. POIR.04.01.04/2019 entitled: INFOLIGHT—“Cloud-based lighting system for smart cities.”]

Novel Electrochemical Determination of Atorvastatin by Monitoring the Suppression of a Lead Probe

This work presents the development of a new electrochemical method for the indirect determination of atorvastatin (ATO) using Pb2+ as a probe at a potential value of -0.40 V. The square-wave voltammetric parameters such as the frequency (50 Hz), amplitude (100 mV) and step size (2 mV) were adjusted to obtain the most symmetrical and intense probe peak. The influences of pH (2.0), background electrolyte composition (HNO3), and probe concentration (250 μmol L−1) were studied in order to achieve highest signal attenuation. The signal suppression mechanism was investigated, indicating that it occurs due to the adsorption of atorvastatin and its oxidation products on the working electrode surface competing with the probe deposition. This suppression approach enhanced the analytical signal by a factor of 100 times when compared to the atorvastatin signal monitoring, leading the optimized method to a limit of quantification (LOQ) of 0.41 μmol L−1 with the linear response up to 2.85 μmol L−1. The repeatability was determined to be 2.95% (n = 10) and the method showed selectivity against other statins (rosuvastatin and pravastatin). As a proof of concept, atorvastatin was determined in a pharmaceutical formulation sample, with a satisfactory recovery of 100.3 ± 3.2%.

Four-wave mixing-based orbital angular momentum translation

We theoretically study the generation of orbital angular momentum (OAM) based on the four-wave mixing process in a diamond-type homogeneously broadened 85 R b atomic system. We use density matrix formalism at a weak field limit to explain the origin of vortex translation between different optical fields and a generated signal. We show how the singularities, which are omnipresent in the phases of the input optical vortex beams, can be profoundly mapped to atomic coherence in the transverse plane, which holds the origin of OAM translation. This translation process works well even for a moderately intense probe and control field, which enhances medium nonlinearity. The generation and manipulation of OAM of the light beam in a nonlinear medium may have important applications in optical tweezers and quantum information processing systems.

Symmetry properties of attosecond transient absorption spectroscopy in crystalline dielectrics

We theoretically investigate a relation between the crystalline symmetry and the transient modulation of optical properties of crystalline dielectrics in pump-probe measurements using intense pump and attosecond probe fields. When the photon energy of the pump field is much below the bandgap energy, the modulation of the optical conductivity is caused by the intraband electronic motion, that is, the dynamical Franz-Keldysh effect. We analytically investigate symmetry properties of the modulated optical conductivity utilizing the Houston function, and derive a formula that relates the temporal oscillation in the absorption with the transformation properties of the modulated optical conductivity. To verify the validity of the formula, we perform real-time first-principles calculations based on the time-dependent density functional theory for a pump-probe process taking 4H-SiC crystal as an example.

Spontaneous loss versus stimulation gain in pump-probe microscopy: a proof of concept demonstration.

.Significance: The large background, narrow dynamic range, and detector saturation have been the common limiting factors in stimulated emission (SE)-based pump-probe microscopy, attributed to the very small signal overriding the very intense laser probe beam. To better differentiate the signal of interest from the background, lock-in detection is used to measure the fluorescence quenching, which is termed spontaneous loss (SL). The advantages are manifold. The spontaneous fluorescence signal can be well separated from both the pump and the probe beams with filters, thus eliminating the background, enlarging the dynamic range, and avoiding the saturation of the detector.Aim: We propose and demonstrate an integrated pump-probe microscopy technique based on lock-in detection for background removal and dynamic range enhancement through SL detection.Approach: The experimental setup is configured with a pulsed diode laser at a wavelength , acting as a pump (excitation) and a mode-locked Ti:sapphire laser at a central wavelength , serving as the probe beam (stimulation). Both pulse trains are temporally synchronized through high precision delay control by adjusting the length of the triggering cables. The pump and probe beams are alternatively modulated at different frequencies and to extract the stimulated gain (SG) and SL signal.Results: SG signal shows saturation due to the irradiation of the intense probe beam onto the photodetector. However, the detector saturation does not occur at high probe beam power for SL detection. The fluorescence lifetime images are acquired with reduced background. The theoretical signal-to-noise ratios for SG and SL are also estimated by photon statistics.Conclusion: We have confirmed that the detection of SL allows the elimination of the large background without photodetector saturation, which commonly exists in SG configuration. This modality would allow unprecedented manipulation and investigation of fluorophores in fluorescence imaging.

Experimental modal analysis and vibro-acoustic testing at leonardo laboratories

This work deals with Experimental Modal Analysis and vibro-acoustic testing performed on several composite panels tested at Leonardo Laboratories, Pomigliano site. The main objective of this paper is to investigate the dynamical behaviour of the structure under test and to evaluate its acoustic properties. Several tests have been performed at the Trasmission Loss Facility of Leonardo.In a modal test, both the applied forces and vibration responses of the excited structure are measured in one or more locations. Exploiting this data, a Modal Model, that essentially contains the same information as the original vibration data, is derived by means of frequency-domain system identification techniques. A home-built Matlab algorithm, named “uMan”, is developed to perform a full Experimental Modal Analysis. Its performances, in terms of capability to build a useful stabilization chart and to curve-fit measured FRFs, are shown. Moreover, a comparison with respect to the state-of-art “Polymax” algorithm in LMS Test.Lab is provided. Finally, the numerical-experimental correlation is performed to verify consistency.The proposed algorithm identifies first mathematical polynomial models, rather than estimating the modal parameters directly from the measurements. Subsequently, these mathematical models are related to the modal parameters. Finally, the obtained Modal Model is compared to the analytical dataset.An acoustic test has been performed to experimentally investigate sound transmission. Two experimental methods have been adopted to evaluate the transmission loss. First, the method that includes measurements of the sound pressure levels using microphones is exploited. Then, the sound intensity method, in which the transmitted sound intensity is measured with a sound intensity probe, is used. By comparing both experimental techniques, the first showed better performance with respect to the other method at low frequencies, while the sound intensity method is more applicable in the medium and high frequency regions in order to predict the noise transmission characteristics.

Surface Chemisty, Microstructure, and Rheology of Thixotropic 1-D Sepiolite Gels

AbstractThe rheological properties of sepiolite gels in relation to solution chemistry, fiber charge, and microstructure are poorly understood. The purpose of this study was to bring more clarity to this topic by quantifying the effects of solution pH, ionic strength, and adsorbed tetrasodium pyrophosphate (TSPP) additive on rheological properties. The electrical charge on sepiolite fibers was investigated to explain the fiber interaction configuration observed in the microstructure. Fiber interaction forces and dynamics explained the ageing behavior of the gel. Sepiolite gels of only a few percent solids displayed long-time ageing behavior, which was manifested by an increasing yield stress with wait time and continued for weeks. The gel microstructure showed randomly orientated rigid fibers with cross configuration attraction. Each fiber experiences both attractive (van der Waals and heterogeneous charge) and repulsive (electric double layer) forces, and initially a net force. The repulsive force causes these fibers to orientate or move continually to achieve a state of force equilibrium and this process takes a long time. The Leong model describes this ageing behavior. For good fiber separation, high intensity probe sonication of the suspension was required. The yield stress increased with sonication time, solids loading, and temperature. The yield stress was absent at pH &gt; 11 and increased to a maximum value at pH &lt; 8. This maximum was insensitive to pH between 4 to 8, and ionic strength up to 1 M KCl. TSPP reduced this maximum and shifted the zero yield stress region to a lower pH, ~7. The zero yield stress state corresponded to a zeta potential with a minimum magnitude of 30 mV.

Performance Analysis of Cost-Effective Miniature Microphone Sound Intensity 2D Probe.

This article presents the functional properties of modified versions of the 2D pressure–pressure intensity probe allowing us to determine the vector of sound intensity on a plane using a mechatronic system with one or two miniature electret microphones. The introduction contains basic information about the application areas of the sound intensity and its measurement problems. Next, the principle of operation of the probes and the construction of the prototype measurement system are described. It was subjected to comparative analysis for the stability of obtained results and accuracy of directional characteristics in free field conditions. For this purpose, experiments were conducted to analyze the flow of acoustic power in an anechoic chamber using both (one- and two-microphone) probes. The results were used for a comparative metrological analysis of the described methods and to indicate the advantages and disadvantages of both constructions. The next part of the article presents an experiment concerning the measurement of the sound intensity impulse response of a room, which is an example of practical use of the probe to analyze reflections in the room, which can be used in sound engineering and architectural acoustics.

Laser-induced alignment dynamics of gas phase CS2 dimers.

Rotational dynamics of gas phase carbon disulfide (CS2) dimers were induced by a moderately intense, circularly polarized alignment laser pulse and measured as a function of time by Coulomb explosion imaging with an intense fs probe pulse. For the alignment pulse, two different temporal intensity profiles were used: a truncated pulse with a 150 ps turn-on and a 8 ps turn-off, or a 'kick' pulse with a duration of 1.3 ps. For both types of pulse, rich rotational dynamics with characteristic full and fractional revivals were recorded, showing that the intermolecular carbon-carbon axis periodically aligns along the propagation direction of the laser pulses. The truncated pulse gave the strongest alignment, which we rationalize as being due to a flat relative phase between the components in the rotational wave packet generated. Fourier analysis of the alignment dynamics gave well-spaced peaks which were fit to determine the rotational constant, B, and the centrifugal constant, DJ, for the ground state of the dimer. Our results agree with values from high-resolution IR spectroscopy. Numerical simulations of the alignment accurately reproduced the experimental dynamics when the truncated pulse or a low intensity kick pulse was used, but failed to reproduce the dynamics induced by a high intensity kick pulse. We posit that the discrepancy is due to excitation of the intermolecular torsional motion by the kick pulse.

‘Have we missed reporting adverse drug reactions under Revised National TB Control Programme?’ - A mixed method study in Bengaluru, India

ObjectivePrompt identification, reporting and management of ADRs during anti tuberculosis treatment can ensure better compliance and treatment outcomes. The study was conducted to identify the gaps and associated factors in reporting of ADRs under RNTCP; assess knowledge, attitude and practice of RNTCP staff regarding pharmacovigilance programme and explore the barriers in reporting of ADRs from provider's perspective. MethodsMixed method research with sequential explanatory design was carried out in Tuberculosis Units of RNTCP administrative district of Bangalore city during July to December 2017. Quantitative study was carried out among 222 patients on intensive phase of Category I and Category II DOTS to study the incidence, severity and causality of ADRs; and records of these patients were analysed for gaps in reporting. Knowledge, attitude and practice (KAP) regarding recording and reporting aspect of pharmacovigilance programme was assessed among RNTCP staff. As part of the qualitative study, focus group discussion was carried out among RNTCP staff to study barriers for reporting ADRs from the provider's perspective. ResultsRecord analysis at the time of recruitment showed documentation of ADRs in only five patients. Subsequent analysis of patient records during the middle and end of the intensive phase (IP) did not show documentation of any ADRs. Simultaneously interviews with patients revealed 116 (52.2%), 72 (32.4%) and 53 (23.8%) patients reported one or more symptoms of ADRs. The commonest ADR symptom reported were fatigability and gastrointestinal symptoms followed by musculoskeletal symptoms. KAP among 25 RNTCP staff showed that 96% of them felt reporting of ADRs was necessary and 92% reported the ADRs to their seniors, however 12% were scared to report. The main reason expressed for non-reporting was ‘managing ADRs is more important than reporting’ (52%). Also, 32% felt the need for retraining of staff on reporting and documentation. Barriers to reporting of ADRs were both health-system related like insufficient training and inadequate guidelines provided to RNTCP staff and patient-related factors like lack of awareness and reluctance to report ADRs. ConclusionSuccessful implementation of RNTCP and achievement of TB elimination requires provision of adequate information regarding ADRs to patients and intense follow-up and probing at each contact by programme staff to effectively manage ADRs.

Estimation of Web Proxy Response Times in Community Networks Using Matrix Factorization Algorithms

In community networks, users access the web using a proxy selected from a list, normally without regard to its performance. Knowing which proxies offer good response times for each client would improve the user experience when navigating, but would involve intensive probing that would in turn cause performance degradation of both proxies and the network. This paper explores the feasibility of estimating the response times for each client/proxy pair by probing only a few of the existing pairs and then using matrix factorization. To do so, response times are collected in a community network emulated on a testbed platform, then a small part of these measurements are used to estimate the remaining ones through matrix factorization. Several algorithms are tested; one of them achieves estimation accuracy with low computational cost, which renders its use feasible in real networks.

Estimating Traffic Intensity Employing Passive Acoustic Radar and Enhanced Microwave Doppler Radar Sensor

Innovative road signs that can autonomously display the speed limit in cases where the traffic situation requires it are under development. The autonomous road sign contains many types of sensors, of which the subject of interest in this article is the Doppler sensor that we have improved and the constructed and calibrated acoustic probe. An algorithm for performing vehicle detection and tracking, as well as vehicle speed measurement, in a signal acquired with a continuous wave Doppler sensor, is discussed. A method is also experimentally presented and studied for counting vehicles and for determining their movement direction by means of acoustic vector sensor application. The assumptions of the method employing spatial distribution of sound intensity determined with the help of an integrated three-dimensional (3D) sound intensity probe are discussed. The enhanced Doppler radar and the developed sound intensity probe were used for the experiments that are described and analyzed in the paper.

Fault Diagnosis of Loader Gearbox Based on an ICA and SVM Algorithm.

When a part of the loader’s gearbox fails, this can lead to equipment failure due to the complex internal structure and the interrelationship between the parts. Therefore, it is imperative to research an efficient strategy for transmission fault diagnosis. In this study, the non-contact characteristics of noise diagnosis using sound intensity probes were used to collect noise signals generated under gear breaking conditions. The independent component analysis (ICA) technique was applied for feature extraction from the original data and to reduce the correlation between the signals. The correlation coefficient between the independent components and the source data was used as the input parameters of the support vector machine (SVM) classifier. The separation of the independent components was achieved by MATLAB simulation. The misdiagnosis rate was 5% for 40 sets of test data. A 13-point test platform for noise testing of the loader gearbox was built according to Chinese national standards. Source signals under the normal and fault conditions were analyzed separately by ICA and SVM algorithms. In this case, the misdiagnosis rate was 7.5% for the 40 sets of experimental test data. This proved that the proposed method could effectively realize fault classification and recognition.