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1.
Sci Data ; 9(1): 599, 2022 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-36195730

RESUMO

Traffic congestion, accidents, and pollution are becoming a challenge for researchers. It is essential to develop new ideas to solve these problems, either by improving the infrastructure or applying the latest technology to use the existing infrastructure better. This research paper presents a high-resolution dataset that will help the research community to apply AI techniques to classify any emergency vehicle from traffic and road noises. Demand for such datasets is high as they can control traffic flow and reduce traffic congestion. It also improves emergency response time, especially for fire and health events. This work collects audio data using different methods, and pre-processed them  to develop a high-quality and clean dataset. The dataset is divided into two labelled classes one for emergency vehicle sirens and one for traffic noises. The developed dataset offers high quality and range of real-world traffic sounds and emergency vehicle sirens. The technical validity of the dataset is also established.


Assuntos
Acidentes de Trânsito , Acidentes de Trânsito/prevenção & controle
2.
PeerJ Comput Sci ; 8: e883, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35494799

RESUMO

Background and Objective: Humans communicate with one another using language systems such as written words or body language (movements), hand motions, head gestures, facial expressions, lip motion, and many more. Comprehending sign language is just as crucial as learning a natural language. Sign language is the primary mode of communication for those who have a deaf or mute impairment or are disabled. Without a translator, people with auditory difficulties have difficulty speaking with other individuals. Studies in automatic recognition of sign language identification utilizing machine learning techniques have recently shown exceptional success and made significant progress. The primary objective of this research is to conduct a literature review on all the work completed on the recognition of Urdu Sign Language through machine learning classifiers to date. Materials and methods: All the studies have been extracted from databases, i.e., PubMed, IEEE, Science Direct, and Google Scholar, using a structured set of keywords. Each study has gone through proper screening criteria, i.e., exclusion and inclusion criteria. PRISMA guidelines have been followed and implemented adequately throughout this literature review. Results: This literature review comprised 20 research articles that fulfilled the eligibility requirements. Only those articles were chosen for additional full-text screening that follows eligibility requirements for peer-reviewed and research articles and studies issued in credible journals and conference proceedings until July 2021. After other screenings, only studies based on Urdu Sign language were included. The results of this screening are divided into two parts; (1) a summary of all the datasets available on Urdu Sign Language. (2) a summary of all the machine learning techniques for recognizing Urdu Sign Language. Conclusion: Our research found that there is only one publicly-available USL sign-based dataset with pictures versus many character-, number-, or sentence-based publicly available datasets. It was also concluded that besides SVM and Neural Network, no unique classifier is used more than once. Additionally, no researcher opted for an unsupervised machine learning classifier for detection. To the best of our knowledge, this is the first literature review conducted on machine learning approaches applied to Urdu sign language.

3.
Clin Infect Dis ; 75(1): e368-e379, 2022 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-35323932

RESUMO

BACKGROUND: In locations where few people have received coronavirus disease 2019 (COVID-19) vaccines, health systems remain vulnerable to surges in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections. Tools to identify patients suitable for community-based management are urgently needed. METHODS: We prospectively recruited adults presenting to 2 hospitals in India with moderate symptoms of laboratory-confirmed COVID-19 to develop and validate a clinical prediction model to rule out progression to supplemental oxygen requirement. The primary outcome was defined as any of the following: SpO2 < 94%; respiratory rate > 30 BPM; SpO2/FiO2 < 400; or death. We specified a priori that each model would contain three clinical parameters (age, sex, and SpO2) and 1 of 7 shortlisted biochemical biomarkers measurable using commercially available rapid tests (C-reactive protein [CRP], D-dimer, interleukin 6 [IL-6], neutrophil-to-lymphocyte ratio [NLR], procalcitonin [PCT], soluble triggering receptor expressed on myeloid cell-1 [sTREM-1], or soluble urokinase plasminogen activator receptor [suPAR]), to ensure the models would be suitable for resource-limited settings. We evaluated discrimination, calibration, and clinical utility of the models in a held-out temporal external validation cohort. RESULTS: In total, 426 participants were recruited, of whom 89 (21.0%) met the primary outcome; 257 participants comprised the development cohort, and 166 comprised the validation cohort. The 3 models containing NLR, suPAR, or IL-6 demonstrated promising discrimination (c-statistics: 0.72-0.74) and calibration (calibration slopes: 1.01-1.05) in the validation cohort and provided greater utility than a model containing the clinical parameters alone. CONCLUSIONS: We present 3 clinical prediction models that could help clinicians identify patients with moderate COVID-19 suitable for community-based management. The models are readily implementable and of particular relevance for locations with limited resources.


Assuntos
COVID-19 , Adulto , COVID-19/diagnóstico , Progressão da Doença , Humanos , Interleucina-6 , Modelos Estatísticos , Alta do Paciente , Segurança do Paciente , Prognóstico , Estudos Prospectivos , Receptores de Ativador de Plasminogênio Tipo Uroquinase , Reprodutibilidade dos Testes , SARS-CoV-2
4.
Sensors (Basel) ; 22(1)2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-35009941

RESUMO

Software-defined network (SDN) and vehicular ad-hoc network (VANET) combined provided a software-defined vehicular network (SDVN). To increase the quality of service (QoS) of vehicle communication and to make the overall process efficient, researchers are working on VANET communication systems. Current research work has made many strides, but due to the following limitations, it needs further investigation and research: Cloud computing is used for messages/tasks execution instead of fog computing, which increases response time. Furthermore, a fault tolerance mechanism is used to reduce the tasks/messages failure ratio. We proposed QoS aware and fault tolerance-based software-defined V vehicular networks using Cloud-fog computing (QAFT-SDVN) to address the above issues. We provided heuristic algorithms to solve the above limitations. The proposed model gets vehicle messages through SDN nodes which are placed on fog nodes. SDN controllers receive messages from nearby SDN units and prioritize the messages in two different ways. One is the message nature way, while the other one is deadline and size way of messages prioritization. SDN controller categorized in safety and non-safety messages and forward to the destination. After sending messages to their destination, we check their acknowledgment; if the destination receives the messages, then no action is taken; otherwise, we use a fault tolerance mechanism. We send the messages again. The proposed model is implemented in CloudSIm and iFogSim, and compared with the latest models. The results show that our proposed model decreased response time by 50% of the safety and non-safety messages by using fog nodes for the SDN controller. Furthermore, we reduced the execution time of the safety and non-safety messages by up to 4%. Similarly, compared with the latest model, we reduced the task failure ratio by 20%, 15%, 23.3%, and 22.5%.

5.
Biomed Res Int ; 2021: 6635964, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33937404

RESUMO

Diagnosis on the basis of a computerized acoustic examination may play an incredibly important role in early diagnosis and in monitoring and even improving effective pathological speech diagnostics. Various acoustic metrics test the health of the voice. The precision of these parameters also has to do with algorithms for the detection of speech noise. The idea is to detect the disease pathology from the voice. First, we apply the feature extraction on the SVD dataset. After the feature extraction, the system input goes into the 27 neuronal layer neural networks that are convolutional and recurrent neural network. We divided the dataset into training and testing, and after 10 k-fold validation, the reported accuracies of CNN and RNN are 87.11% and 86.52%, respectively. A 10-fold cross-validation is used to evaluate the performance of the classifier. On a Linux workstation with one NVidia Titan X GPU, program code was written in Python using the TensorFlow package.


Assuntos
Redes Neurais de Computação , Distúrbios da Voz/diagnóstico , Algoritmos , Bases de Dados como Assunto , Humanos , Modelos Teóricos
6.
Math Biosci Eng ; 18(3): 2258-2273, 2021 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-33892544

RESUMO

Voice pathologies are irregular vibrations produced due to vocal folds and various factors malfunctioning. In medical science, novel machine learning algorithms are applied to construct a system to identify disorders that occur invoice. This study aims to extract the features from the audio signals of four chosen diseases from the SVD dataset, such as laryngitis, cyst, non-fluency syndrome, and dysphonia, and then compare the four results of machine learning algorithms, i.e., SVM, Naïve Byes, decision tree and ensemble classifier. In this project, we have used a comparative approach along with the new combination of features to detect voice pathologies which are laryngitis, cyst, non-fluency syndrome, and dysphonia from the SVD dataset. The combination of specific 13 MFCC (mel-frequency cepstral coefficients) features along with pitch, zero crossing rate (ZCR), spectral flux, spectral entropy, spectral centroid, spectral roll-off, and short term energy for more accurate detection of voice pathologies. It is proven that the combination of features extracted gives the best product on the audio, which split into 10 ms. Four machine learning classifiers, SVM, Naïve Bayes, decision tree and ensemble classifier for the inter classifier comparison, give 93.18, 99.45,100 and 51%, respectively. Out of these accuracies, both Naïve Bayes and the decision tree show the most promising results with a higher detection rate. Naïve Bayes and decision tree gives the highest reported outcomes on the selected set of features in the proposed methodology. The SVM has also been concluded to be the commonly used voice condition identification algorithm.


Assuntos
Algoritmos , Máquina de Vetores de Suporte , Teorema de Bayes , Aprendizado de Máquina
7.
Math Biosci Eng ; 17(6): 7958-7979, 2020 11 11.
Artigo em Inglês | MEDLINE | ID: mdl-33378928

RESUMO

Background and Objective: Voice disorders are pathological conditions that directly affect voice production. Computer based diagnosis may play a major role in the early detection and in tracking and even development of efficient pathological speech diagnosis, based on a computerized acoustic evaluation. The health of the Voice is assessed by several acoustic parameters. The exactness of these parameters is often linked to algorithms used to estimate them for speech noise identification. That is why main effort of the scientists is to study acoustic parameters and to apply classification methods that achieve a high precision in discrimination. The primary aim of this paper is for a meta-analysis on voice disorder databases i.e. SVD, MEEI and AVPD and machine learning techniques applied on it. Materials and Methods: This field of study was systematically reviewed in compliance with PRISMA guidelines. A search was performed with a set of formulated keywords on three databases i.e. Science Direct, PubMed, and IEEE Xplore. A proper screening and analysis of articles were performed after which several articles were also excluded. Results: Forty-five studies that fulfills the eligibility criteria were included in this meta-analysis. After applying eligibility criteria on the peer reviewed and research article and studies that were published in authentic journals and conferences proceedings till June 2020 were chosen for further full-text screening. In general, only those articles that used voice recordings from SVD, MEEI and AVPD databases as a dataset is included in this meta-analysis. Conclusion: We discussed the strengths and weaknesses of SVD, MEEI and AVPD. After detailed analysis of the studies including the techniques used and outcome measurements, it was also concluded that Support Vector Machine (SVM) is the most common used algorithm for the detection of voice disorders. Other than was also noticed that researchers focus on supervised techniques for the clinical diagnosis of voice disorder rather than using unsupervised techniques. It was also concluded that more work needs to be on voice pathology detection using AVPD database.


Assuntos
Aprendizado de Máquina , Distúrbios da Voz , Acústica , Algoritmos , Bases de Dados Factuais , Humanos , Distúrbios da Voz/diagnóstico
8.
J Nat Prod ; 70(5): 849-52, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17385913

RESUMO

Microbial transformation of the sesquiterpene (-)-guaiol (1) [1(5)-guaien-11-ol] was investigated using three fungi, Rhizopus stolonifer, Cunninghamella elegans, and Macrophomina phaseolina. Fungal transformation of 1 with Rhizopus stolonifer yielded a hydroxylated product, 1-guaiene-9 beta,11-diol (2). In turn, Cunninghamella elegans afforded two mono- and dihydroxylated products, 1-guaiene-3beta,11-diol (3) and 1(5)-guaiene-3beta,9 alpha,11-triol (4), while Macrophomina phaseolina produced two additional oxidative products, 1(5)-guaien-11-ol-6-one (5) and 1-guaien-11-ol-3-one (6). All metabolites were found to be new compounds as deduced on the basis of spectroscopic techniques. Compounds 1-6 were evaluated for their activity against several bacterial strains.


Assuntos
Antibacterianos/farmacologia , Sesquiterpenos/metabolismo , Antibacterianos/química , Antibacterianos/metabolismo , Bactérias/efeitos dos fármacos , Cunninghamella/química , Testes de Sensibilidade Microbiana , Fungos Mitospóricos/química , Estrutura Molecular , Rhizopus/química , Sesquiterpenos/química , Sesquiterpenos/farmacologia , Sesquiterpenos de Guaiano , Estereoisomerismo
9.
Chem Biodivers ; 3(1): 54-61, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17193216

RESUMO

The transformation of the antibacterial diterpene sclareol (1) by two different fungal strains was investigated (Scheme). In the presence of Rhizopus stolonifer, (3beta)-3-hydroxysclareol (2), 18-hydroxysclareol (3), (6alpha)-6,18-dihydroxysclareol (4), and (11S)-11,18-dihydroxysclareol (5) were formed. Fermentation of 1 with Fusarium lini afforded (1beta)-1-hydroxysclareol (6) and (12S)-12-hydroxysclareol (7). Compounds 4-7 were identified as new compounds, and some of them were active against Bacillus subtilis (Table 3).


Assuntos
Antibacterianos/química , Antibacterianos/metabolismo , Diterpenos/metabolismo , Fusarium/metabolismo , Rhizopus/metabolismo , Diterpenos/química , Relação Estrutura-Atividade
10.
Bioorg Med Chem ; 14(14): 4704-11, 2006 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-16603364

RESUMO

Synthesis of flavones, 4-thioflavones and 4-iminoflavones was carried out with the substitution of variable halogens, methyl, methoxy and nitro groups in the A, B and AB rings of the respective compounds and we also report here their antibacterial activity. Most of the synthesized compounds were found to be active against Escherichia coli, Bacillus subtilis, Shigella flexnari, Salmonella aureus, Salmonella typhi and Pseudomonas aeruginosa. Activity of 4-thioflavones and 4-iminoflavones was found to be higher than that of their corresponding flavone analogues. Investigated compounds having substituents like F, OMe and NO2 at 4'-position in ring-B exhibited enhanced activity and the presence of electronegative groups in the studied compounds showed a direct relationship to the antibacterial activity.


Assuntos
Antibacterianos/síntese química , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Flavonas/síntese química , Flavonas/farmacologia , Antibacterianos/química , Bacillus subtilis/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Flavonas/química , Testes de Sensibilidade Microbiana , Pseudomonas aeruginosa/efeitos dos fármacos , Salmonella typhi/efeitos dos fármacos , Shigella flexneri/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Relação Estrutura-Atividade
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