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1.
ISA Trans ; 100: 322-333, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-31759684

RESUMEN

Strong electromagnetic fields such as those generated by power stations and transmission lines cause disturbances that affect the on-board sensors of an autonomous unmanned aerial vehicles (AUAVs) and may lead to aircraft instability. To mitigate this effect, we use an extended Kalman filter with colored noise. In addition to the traditional aircraft dynamics, this approach considers the electromagnetic fields of transmission lines and their position, electrical current, and tower topology. In this way, the filter can predict and correct the interference in the aircraft sensors, thereby guaranteeing flight stability even when the AUAV is very close to the electromagnetic sources. This approach enables the AUAV to operate closer to the transformers and transmission lines, thereby paving the way for better autonomous inspection performed by electrical companies and further development of new technologies. To prove the effectiveness of this approach, theoretical and practical results involving a survey of transmission lines are demonstrated.

2.
Rev. chil. dermatol ; 35(3): 95-101, 2019. ilus
Artículo en Español | LILACS | ID: biblio-1116407

RESUMEN

Debido al acelerado envejecimiento de la población, cada vez es mayor la cantidad de usuarios portado-res de dispositivos electrónicos cardíacos implan-tables (DECI). Muchos de estos pacientes se verán enfrentados a procedimientos dermatológicos que con frecuencia utilizan equipos de electrocirugía. Es-tos tienen riesgo potencial de producir interferencias electromagnéticas (IEM), y por lo tanto alterar el fun-cionamiento de estos dispositivos. Si bien no todos los DECI tienen las mismas características, las nuevas tec-nologías de estos dispositivos han disminuido, aunque no eliminado completamente, el riesgo de IEM. Este artículo tiene como propósito revisar el tema y recopilar las recomendaciones generales que todo dermatólogo debe conocer tanto en la fase preoperatoria, intraoperatoria, como postoperatoria al utilizar equipos de electrocirugía en un paciente con DECI.


Due to the accelerated population aging, an increa-sing number of users is carrying cardiac implantable electronic devices (CIEDs). Many of these patients will face dermatological procedures that often use electrosurgical equipment. The latter has the poten-tial to produce electromagnetic interference (EMI), and therefore alter the operation of these devices. While not all CIEDs have the same characteristics, new technologies for these devices have decreased if not eliminated completely the risk of EMI.The purpose of this article is to review CIED topic and compile general recommendations that every dermatologist should be aware of, both in the preoperative, intraoperative, and postoperative phases when using electrosurgery equipment in a patient with CIED.


Asunto(s)
Humanos , Marcapaso Artificial , Desfibriladores Implantables , Campos Electromagnéticos/efectos adversos , Electrocirugia/métodos , Procedimientos Quirúrgicos Dermatologicos , Cuidados Posoperatorios , Cuidados Preoperatorios , Corazón Auxiliar , Complicaciones Intraoperatorias/prevención & control
3.
Acta Odontol Scand ; 75(8): 584-587, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28799814

RESUMEN

OBJECTIVE: Implantable cardioverter defibrillators (ICDs) are subject to electromagnetic interference (EMI). The aim of this study was to assess both the EMI of dental equipments with ICDs and related factors. MATERIALS AND METHODS: High- and low-speed handpieces, an electric toothbrush, an implant motor and two types of ultrasonic devices were tested next to an ICD with different sensitivity settings. The ICD was immersed in a saline solution with electrical resistance of 400-800 ohms to simulate the resistance of the human body. The dental equipments were tested in both horizontal (0°) and vertical (90°) positions in relation to the components of the ICD. The tests were performed with a container containing saline solution, which was placed on a dental chair in order to assess the cumulative effect of electromagnetic fields. RESULTS: The dental chair, high- and low-speed handpieces, electric toothbrush, implant motor and ultrasonic devices caused no EMI with the ICD, irrespective of the program set-up or positioning. No cumulative effect of electromagnetic fields was verified. CONCLUSIONS: The results of this study suggest that the devices tested are safe for use in patients with an ICD.


Asunto(s)
Desfibriladores Implantables , Equipo Dental/efectos adversos , Campos Electromagnéticos/efectos adversos , Impedancia Eléctrica/efectos adversos , Humanos , Ultrasonido
4.
Int Endod J ; 49(6): 526-32, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26105663

RESUMEN

AIM: To evaluate the potential for electromagnetic interference (EMI) of electronic apex locators (EALs) and a gutta-percha heating device (HD) in patients with implantable cardiac pacemakers (ICPs) or cardioverter-defibrillators (ICDs). METHODOLOGY: Two types of EALs (Romiapex A-15 and Novapex) and a HD (Touch'n Heat) were tested in patients followed in an outpatient clinic for cardiac arrhythmias. The heart rhythm was monitored on a computer screen during all experimental phases. After baseline data collection, the patient held each appliance (turned on) for 30 s, simulating their clinical use. If background noise was detected on the cardiac monitor, the sensitivity of the ICP/ICD was lowered by the cardiologist to evaluate the intensity of the detected EMI. RESULTS: Twelve patients were evaluated (5 female and 7 male), and in nine instances, background noise in their cardiac devices related to the use of the endodontic devices was detected (6 patients). After lowering the sensitivity of the cardiac implants, three patients had more severe EMI in six instances, including pauses in ICP function. The presence of a symptomatic or asymptomatic pause was related to the patient's underlying heart rhythm. The HD device produced background noise more often compared to EALs. These were associated with more severe types of EMI. CONCLUSION: The EALs and gutta-percha HD were capable of causing background noise detection or pauses in cardiac implants in vivo. The use of electronic dental devices nearby patients with cardiac implants should be carefully considered in clinical practice.


Asunto(s)
Desfibriladores Implantables , Equipo Dental/efectos adversos , Odontometría/efectos adversos , Marcapaso Artificial , Ápice del Diente , Anciano , Anciano de 80 o más Años , Arritmias Cardíacas/terapia , Desfibriladores Implantables/efectos adversos , Endodoncia/instrumentación , Femenino , Gutapercha , Calefacción/efectos adversos , Humanos , Masculino , Persona de Mediana Edad , Odontometría/instrumentación , Marcapaso Artificial/efectos adversos
5.
Rev. bras. eng. biomed ; 29(3): 269-277, set. 2013. ilus, tab
Artículo en Inglés | LILACS | ID: lil-690215

RESUMEN

INTRODUCTION: Electromagnetic interference caused by electric power lines adversely affects the signals of electronic instruments, especially those with low amplitude levels. This type of interference is known as common-mode interference. There are many methods and architectures used to minimize the influence of this kind of interference on electronic instruments, the most common of which is the use of band-reject filters. This paper presents the analysis, development, prototype and test of a new reconfigurable filter architecture for biomedical instruments, aiming to reduce the common-mode interference and preserve the useful signal components in the same frequency range as that of the noise, using the technique of dynamic impedance balancing. METHODS: The circuit blocks were mathematically modeled and the overall closed-loop transfer function was derived. Then the project was described and simulated in the VHDL_AMS language and also in an electronics simulation software, using discrete component blocks, with and without feedback. After theoretical analysis and simulation results, a prototype circuit was built and tested using as input a signal obtained from ECG electrodes. RESULTS: The results from the experimental circuit matched those from simulation: a 97.6% noise reduction was obtained in simulations using a sinusoidal signal, and an 86.66% reduction was achieved using ECG electrodes in experimental tests. In both cases, the useful signal was preserved. CONCLUSION: The method and its architecture can be applied to attenuate interferences which occur in the same frequency band as that of the useful signal components, while preserving these signals.

6.
Rev. bras. eng. biomed ; 24(3): 215-227, dez. 2008. ilus, tab, graf
Artículo en Portugués | LILACS | ID: lil-548022

RESUMEN

A crescente inserção de tecnologia eletroeletrônica em estabelecimentos assistenciais de saúde (EAS), seja como equipamentos terapêuticos, de diagnóstico ou até mesmo suporte vital, tem sido vista pela comunidade científica como a grande responsável pelo aumento dos níveis de energia eletromagnética emitidos ao ambiente hospitalar. Dessa forma, quando a energia eletromagnética presente no ambiente atinge um determinado nível crítico, fica estabelecida uma situação que é propícia ao aparecimento de dois fenômenos indesejados: a interferência eletromagnética (EMI) em equipamentos médicos, e os riscos biológicos (RBL) em seres vivos. Um importante recurso para gerenciar a compatibilidade eletromagnética e evitar o aparecimento destes fenômenos é o conhecimento das características eletromagnéticas presentes nestes ambientes. O objetivo deste trabalho é diagnosticar o comportamento eletromagnético estabelecido em ambientes de grande concentração de fontes emissoras como, por exemplo, o encontrado em centros cirúrgicos, através de uma série de medições in situ das grandezas eletromagnéticas envolvidas nestes meios (campos elétricos, campos magnéticos, ruídos conduzidos). Com base nestas medidas é realizada uma avaliação crítica de modo a comparar a situação estabelecida nos EAS e os limites de segurança preconizados por organismos competentes, tanto para EMI quanto para RBL. Como resultado desta análise, começa a existir maior discernimento quanto à real situação do ambiente eletromagnético encontrado em EAS nacionais, subsidiando informações para a definição de diretrizes mais eficientes para implementação de programas de gestão tecnológica que são direcionados às necessidades específicas destes hospitais.


Advances in technology and the increased use of electro-medical equipment (EME) to support medical procedures such as monitoring, diagnosis, therapeutic or even life support are considered as greatly responsible for the increase of electromagnetic energy within health care facilities (HCF) environments. In such circumstances, when electromagnetic energy reaches a certain critical level, a dangerous situation is established and two undesirable phenomena can take place, both electromagnetic interference (EMI) in medical equipment, and biological risks (BLR) in living beings. The knowledge of electromagneticcharacteristics shown by these environments can represent an important tool in order to promote electromagnetic compatibility and avoid the appearance of undesirable phenomena. Therefore, this work aims to diagnose the electromagnetic profile established in critical areas, such as operating rooms, through a number of “in situ” measurements concerning electromagnetic quantities present in this environment (electric field, magnetic field, conducted noise). Moreover, a critical evaluation follows in order to compare the establishedsituation within HCF and the safety levels prescribed by regulatory organizations regarding EMI and BLR. As a result of this assessment, a better understanding on the actual situation concerning the electromagnetic environment in HCF can be achieved, allowing clinical engineers to define better directives in order to implement an adequate management programs in these hospitals.


Asunto(s)
Campos Electromagnéticos/efectos adversos , Contención de Riesgos Biológicos/métodos , Contención de Riesgos Biológicos/normas , Fuentes de Radiación , Monitoreo de Radiación/estadística & datos numéricos , Monitoreo de Radiación/instrumentación , Monitoreo de Radiación/métodos , Monitoreo de Radiación/normas , Equipos y Suministros de Hospitales , Equipos y Suministros de Hospitales/efectos adversos , Equipos y Suministros de Hospitales/normas
7.
Rev. bras. eng. biomed ; 23(1): 17-23, abr. 2007. ilus, tab, graf
Artículo en Inglés | LILACS | ID: lil-483520

RESUMEN

A interferência eletromagnética pode causar problemas no funcionamento de equipamentos eletromédicos. Dentre as fontes radiantes de interferência encontradas na literatura, os telefones celulares e as unidades eletrocirúrgicas vêm recebendo atenção especial. Rotineiramente, essas fontes operam simultaneamente em pequenos espaços físicos, como as salas cirúrgicas. Este estudo apresenta uma sondagem da intensidade de campo elétrico ambiente em salas cirúrgicas durante a intervenção médica. As medições aconteceram em centros cirúrgicos de três hospitais com o emprego de um medidor isotrópicos de campo elétrico com sensor calibrado. Sete diferentes tipos de cirurgia foram monitorados. Para evitar a obtenção de intensidades de campo discrepantes nas medições, os experimentos aconteceram nas salas cirúrgicas disponíveis que apresentaram disposição similaar de objetos e móveis cirúrgicos e equipamentos eletromédicos. O medidor de campo adquiriu as medidas em quatro pontos ao redor da mesa cirúrgica. A comunicação remota entre o medidor dentro da sala cirúrgica e um computador portátil fora da sala foi estabelecida por meio de um cabo de fibra ótica. Quinze minutos em cado ponto totalizaram 1 hora de observação por cirurgia. O medidor registrou valores de campo elétrico mais elevados que o nível basal quando do acionamento da unidade eletrocirúrgica. O valor médio de campo elétrico variou entre 1,1 mais ou menos 0,3 V/m e 3,0 mais ou menos 1,2 V/m. Contudo, intensidades mais elevadas de campo elétrico foram observadas, como 9,1 V/m, para distâncias maiores que 2,0 m. Os campos elétricos registrados resultam da integração de todos os campos existentes no espectro de freqüências que o medidor é capaz de monitorar. Por esse motivo, o medidor não consegue determinar os campos elétricos na freqüência de operação de um equipamento eletrodoméstico específico, diferentemente de um analisador de espectro. Porém, ele apresentou o impacto causado pela ativação da unidade eletro...


Asunto(s)
Radiación no Ionizante , Campos Electromagnéticos/efectos adversos , Medición de Riesgo/métodos , Quirófanos , Riesgos Laborales , Seguridad de Equipos/métodos
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