A robust sequential hypothesis testing method for brake squeal localisation

This contribution deals with the in situ detection and localisation of brake squeal in an automobile. As brake squeal is emitted from regions known a priori, i.e., near the wheels, the localisation is treated as a hypothesis testing problem. Distributed microphone arrays, situated under the automobile, are used to capture the directional properties of the sound field generated by a squealing brake. The spatial characteristics of the sampled sound field is then used to formulate the hypothesis tests. However, in contrast to standard hypothesis testing approaches of this kind, the propagation environment is complex and time-varying. Coupled with inaccuracies in the knowledge of the sensor and source positions as well as sensor gain mismatches, modelling the sound field is difficult and standard approaches fail in this case. A previously proposed approach implicitly tried to account for such incomplete system knowledge and was based on ad hoc likelihood formulations. The current paper builds upon this approach and proposes a second approach, based on more solid theoretical foundations, that can systematically account for the model uncertainties. Results from tests in a real setting show that the proposed approach is more consistent than the prior state-of-the-art. In both approaches, the tasks of detection and localisation are decoupled for complexity reasons. The localisation (hypothesis testing) is subject to a prior detection of brake squeal and identification of the squeal frequencies. The approaches used for the detection and identification of squeal frequencies are also presented. The paper, further, briefly addresses some practical issues related to array design and placement. (C) 2019 Author(s)

Novel Stepped Impedance Microstrip Bandpass Filters for Radar Applications

In this paper, the design and realization of A Novel Microstrip Stepped Impedance Resonator Bandpass Filters with two selected center frequencies (f0) 12GHz and 16GHz presented. For The design of Band pass Filters “Rogers 6035HTC" substrate material with relative dielectric constant of 3.55, Standard thickness of 0.020” (0.508mm), thickness of pec is 0.035mm and simulated on High Frequency System Simulator (HFSS). Both the designed filters performances are discussed and compared with literature. The designed Stepped Impedance microstrip BPFs have insertion loss of <1dB with the optimal average performance of 37% and 32% FBW, and return losses are 47 dB and 32dB, which is reported better when compared with the reference designs

TOP-K QUERY DISPENSATION IN SECURE SPATIAL ENVIRONMENT VIA UNTRUSTED LOCATION-BASED SERVICE PROVIDERS

IN Collaborative location-based information generation and sharing is considered, which become increasingly popular due to the explosive growth of Internet-capable and location-aware mobile devices. The system consists of a data collector, data contributors, location-based service providers (LBSPs), and system users. The data collector gathers reviews about points-of-interest (POIs) from data contributors, while LBSPs purchase POI data sets from the data collector and allow users to perform spatial top-k queries which ask for the POIs in a certain region and with the highest k ratings for an interested POI attribute. In practice, LBSPs are untrusted and may return fake query results for various bad motives, e.g., in favor of POIs willing to pay. Three novel schemes is used for users to detect fake spatial snapshot and moving top-k query results as an effort to foster the practical deployment and use of the proposed system

Evaluation of the effects of tramadol and diclofenac alone and in combination on post-cesarean pain

Background: Post-cesarean pain is a common cause of acute pain in the obstetrics. Pain in the postoperative period is an important impediment to recovery from surgery and anesthesia. This study was conducted to evaluate the efficacy of postoperative analgesia and incidence of side-effects of centrally acting drug tramadol with peripherally acting drug diclofenac alone and in combination in patients undergoing elective cesarean delivery under spinal anesthesia.Methods: The study population of 90 patients was randomly divided into three groups of 30 each to receive the following treatments: tramadol (Group T), diclofenac (Group D), tramadol and diclofenac at reduced doses (Group TD).Results: Combination of tramadol and diclofenac produced significantly early analgesia in comparison to tramadol or diclofenac alone and decrease in the incidence of side-effects.Conclusion: We conclude that a multimodal approach to post-cesarean management with a combination of tramadol and diclofenac produced better analgesia than individual drugs and a reduction in the side-effects. Such a combination approach to relieve pain is more effective and advantageous

Response of Degarelix treatment in human prostate cancer monitored by HR-MAS 1H NMR spectroscopy.

INTRODUCTION: The androgen receptor (AR) is the master regulator of prostate cancer cell metabolism. Degarelix is a novel gonadotrophin-releasing hormone blocker, used to decrease serum androgen levels in order to treat advanced human prostate cancer. Little is known of the rapid metabolic response of the human prostate cancer tissue samples to the decreased androgen levels. OBJECTIVES: To investigate the metabolic responses in benign and cancerous tissue samples from patients after treatment with Degarelix by using HRMAS 1H NMR spectroscopy. METHODS: Using non-destructive HR-MAS 1H NMR spectroscopy we analysed the metabolic changes induced by decreased AR signalling in human prostate cancer tissue samples. Absolute concentrations of the metabolites alanine, lactate, glutamine, glutamate, citrate, choline compounds [t-choline = choline + phosphocholine (PC) + glycerophosphocholine (GPC)], creatine compounds [t-creatine = creatine (Cr) + phosphocreatine (PCr)], taurine, myo-inositol and polyamines were measured in benign prostate tissue samples (n = 10), in prostate cancer specimens from untreated patients (n = 7) and prostate cancer specimens from patients treated with Degarelix (n = 6). RESULTS: Lactate, alanine and t-choline concentrations were significantly elevated in high-grade prostate cancer samples when compared to benign samples in untreated patients. Decreased androgen levels resulted in significant decreases of lactate and t-choline concentrations in human prostate cancer biopsies. CONCLUSIONS: The reduced concentrations of lactate and t-choline metabolites due to Degarelix could in principle be monitored by in vivo 1H MRS, which suggests that it would be possible to monitor the effects of physical or chemical castration in patients by that non-invasive method.We acknowledge the support of The University of Cambridge, Cancer Research UK (C14303/A17197) and Hutchison Whampoa Limited. The Human Research Tissue Bank is supported by the NIHR Cambridge Biomedical Research Centre.This is the final version of the article. It first appeared from Springer via http://dx.doi.org/10.1007/s11306-016-1055-0

Progressive Failure And Life Prediction of Ceramic and Textile Composites

An engineering approach to predict the fatigue life and progressive failure of multilayered composite and textile laminates is presented. Analytical models which account for matrix cracking, statistical fiber failures and nonlinear stress-strain behavior have been developed for both composites and textiles. The analysis method is based on a combined micromechanics, fracture mechanics and failure statistics analysis. Experimentally derived empirical coefficients are used to account for the interface of fiber and matrix, fiber strength, and fiber-matrix stiffness reductions. Similar approaches were applied to textiles using Repeating Unit Cells. In composite fatigue analysis, Walker's equation is applied for matrix fatigue cracking and Heywood's formulation is used for fiber strength fatigue degradation. The analysis has been compared with experiment with good agreement. Comparisons were made with Graphite-Epoxy, C/SiC and Nicalon/CAS composite materials. For textile materials, comparisons were made with triaxial braided and plain weave materials under biaxial or uniaxial tension. Fatigue predictions were compared with test data obtained from plain weave C/SiC materials tested at AS&M. Computer codes were developed to perform the analysis. Composite Progressive Failure Analysis for Laminates is contained in the code CPFail. Micromechanics Analysis for Textile Composites is contained in the code MicroTex. Both codes were adapted to run as subroutines for the finite element code ABAQUS and CPFail-ABAQUS and MicroTex-ABAQUS. Graphic user interface (GUI) was developed to connect CPFail and MicroTex with ABAQUS

Selection of Oil and best Bio-diesel Blend based on Performance and Emission Characteristics of IC Engine: An Integrated CRITIC-TOPSIS Approac

Selection of optimum bio-diesel blend for internal combustion (IC) engine is crucial. The process of selecting the ideal blend requires a multidimensional analysis. In order to tackle the challenge, an efficient decision-making strategy is required. This paper uses the Multi-Criteria Decision-Making (MCDM) method to offer the selection of a suitable oil and bio-diesel blend based on the performance of the diesel engine under various load circumstances. In order to measure the weights of evaluating criteria, Criteria Importance Through Intercriteria Correlation (CRITIC) and Technique for Order of Preference by Similarity to an Ideal Solution (TOPSIS) are used. At first, seven different oils and seven assessment parameters, namely kinematic viscosity, cetane number, heating value, cloud point, pour point, flash point and density are attempted to select the acceptable oil for making bio-diesel. Next, the ranking of bio-diesel blends is performed based on the evaluation criteria, namely Brake Thermal Efficiency (BTE), Exhaust Gas Temperature (EGT), nitrogen oxide (NOx), smoke, carbon monoxide (CO), carbon dioxide (CO2) and hydrocarbon (HC) emissions. The results show that hemp seed oil is closer to diesel and higher in ranking. The recommended order of blend is B20 > Diesel > B40 > B60 > B80 > B100. The study indicated that B20 is the optimum blend for diesel engines. In order to meet the economy and pollution standards for the green revolution, decision-makers can use the new insights into MCDM approaches described in this article. This study also demonstrates that the suggested methods for choosing the best bio-diesel blend differ from the existing literature

The automatic detection of heart failure using speech signals

Heart failure (HF) is a major global health concern and is increasing in prevalence. It affects the larynx and breathing - thereby the quality of speech. In this article, we propose an approach for the automatic detection of people with HF using the speech signal. The proposed method explores mel-frequency cepstral coefficient (MFCC) features, glottal features, and their combination to distinguish HF from healthy speech. The glottal features were extracted from the voice source signal estimated using glottal inverse filtering. Four machine learning algorithms, namely, support vector machine, Extra Tree, AdaBoost, and feed-forward neural network (FFNN), were trained separately for individual features and their combination. It was observed that the MFCC features yielded higher classification accuracies compared to glottal features. Furthermore, the complementary nature of glottal features was investigated by combining these features with the MFCC features. Our results show that the FFNN classifier trained using a reduced set of glottal + MFCC features achieved the best overall performance in both speaker-dependent and speaker-independent scenarios. (C) 2021 The Author(s). Published by Elsevier Ltd.Peer reviewe

A Quantitative Systems Approach Reveals Dynamic Control of tRNA Modifications during Cellular Stress

Decades of study have revealed more than 100 ribonucleoside structures incorporated as post-transcriptional modifications mainly in tRNA and rRNA, yet the larger functional dynamics of this conserved system are unclear. To this end, we developed a highly precise mass spectrometric method to quantify tRNA modifications in Saccharomyces cerevisiae. Our approach revealed several novel biosynthetic pathways for RNA modifications and led to the discovery of signature changes in the spectrum of tRNA modifications in the damage response to mechanistically different toxicants. This is illustrated with the RNA modifications Cm, m[superscript 5]C, and m[superscript 2][subscript 2]G, which increase following hydrogen peroxide exposure but decrease or are unaffected by exposure to methylmethane sulfonate, arsenite, and hypochlorite. Cytotoxic hypersensitivity to hydrogen peroxide is conferred by loss of enzymes catalyzing the formation of Cm, m[superscript 5]C, and m[superscript 2][subscript 2]G, which demonstrates that tRNA modifications are critical features of the cellular stress response. The results of our study support a general model of dynamic control of tRNA modifications in cellular response pathways and add to the growing repertoire of mechanisms controlling translational responses in cells.National Institute of Environmental Health Sciences (ES002109)National Institute of Environmental Health Sciences (ES017010)National Institute of Environmental Health Sciences (ES015037)National Cancer Institute (U.S.) (CA026731)National Center for Research Resources (U.S.) (RR023783)Singapore-MIT Alliance for Research and Technolog