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1.
HardwareX ; 13: e00403, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36875259

RESUMO

The use of IoT systems that support the construction of smart cities is a global trend that directly affects the quality of life of citizens. for vehicular and pedestrian traffic, the detection of living beings and especially of humans, is a way of quantifying different variables pertinent to the improvement of roads, traffic flows, frequency of visits, among others. the implementation of low-cost systems that do not involve high-processing systems makes the solutions more scalable at a global level. The data acquired by this type of device offers advantages to the different entities in statistics and public consultations, thus contributing to their growth. In this article, an assistance system for the task of pedestrian flow detection is designed and constructed. It integrates strategically located arrays of sensors to detect the direction and general location, which include microwave sensors to detect motion, and infrared presence sensors. The results demonstrate that the system manages to establish the direction of flow of the individual and laterally of the displacement and differentiation between humans and objects for assistance to other systems of counting or analysis of pedestrian flow.

2.
Sensors (Basel) ; 22(17)2022 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-36080789

RESUMO

This work presents a novel methodology to implement a fuzzy inference system (FIS) to overcome the measurement ambiguity that is typically observed in interferometric sensors. This ambiguity occurs when the measurand is determined by tracing the wavelength position of a peak or dip of a spectral fringe. Consequently, the sensor measurement range is typically limited to the equivalent of 1 free spectral range (FSR). Here, it is demonstrated that by using the proposed methodology, the measurement range of this type of sensor can be widened several times by overcoming the ambiguity over some FSR periods. Furthermore, in order to support the viability of the methodology, it was applied to a couple of temperature interferometric sensors. Finally, experimental results demonstrated that it was possible to quintuple the measurement range of one of the tested sensors with a mean absolute error of MAE = 0.0045 °C, while for the second sensor, the measurement range was doubled with an MAE = 0.0073 °C.

3.
Sensors (Basel) ; 20(18)2020 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-32911731

RESUMO

This paper presents the design of a current-mode CMOS self-amplified imager operating in dark conditions, for thermal imaging, which provides an innovative solution for precision thermal contact mapping. Possible applications of this imager range from 3D CMOS integrated circuits to the study of in-vivo biological samples. It can provide a thermal map, static or dynamic, for the measurement of temperature microgradients. Some adaptations are required for the optimization of this self-amplified image sensor since it responds exclusively to the dark currents of the photodiodes throughout the array. The sensor is designed in a standard CMOS process and requires no post-processing steps. The optimized image sensor operates with integration times as low as one µs and can achieve both SNR and dynamic range compatible to those of sensors available on the market, estimated as 87dB and 75dB, respectively; noise equivalent temperature difference can be as low as 10mK; and detection errors as low as ±1%. Furthermore, under optimal conditions the self-amplification process enables a simple form of CDS, enhancing the overall sensor noise performance.

4.
Data Brief ; 30: 105547, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32373686

RESUMO

This dataset is part of the article entitled "Design and experimental study of a low-cost prefab Trombe Wall to improve indoor temperatures in social housing in the Biobío Region in Chile" [1], [2]. The dataset represents the outcome of experimental measurements during a 1-year monitoring campaign to assess the performance of an adaptable and low-cost prefabricated Trombe Wall (TW) with a vertical water storage system. The experiments include periods with mobile insulation during winter nights and external shading during summer which were added to test their effect on the thermal performance. Temperature sensors were used to measure and compare the temperature in two test cells: one with and one without the TW. Following the National Chilean Standard [3], the experiment was done in the interior valley (Chillan), a Mediterranean climate (Csb), according to the Köppen climate classification [4]. The two test cells were designed to represent the most used area of a social housing unit in combination with the most widely used type of window in north façades in the region. One test cell was built exactly as the social housing unit, while the second test cell included a low-cost Trombe wall. Five temperature sensors were installed in the test cells. The thermal performance of the TW was monitored and analysed for the first time in Chile, providing insights in the thermal performance of the TW and proving the potential effectiveness of seasonal variations to improve winter and summer performances.

5.
Sensors (Basel) ; 17(2)2017 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-28146068

RESUMO

This paper describes the design, fabrication, and testing of two hollow prisms. One is a prism with a grating glued to its hypotenuse. This ensemble, prism + grating, is called a grism. It can be applied as an on-axis tunable spectrometer. The other hollow prism is a constant deviation one called a Pellin-Broca. It can be used as a tunable dispersive element in a spectrometer with no moving parts. The application of prisms as temperature sensors is shown.

6.
Piracicaba; s.n; 10/04/2014. 111 p. ilus, tab, graf.
Tese em Português | VETINDEX | ID: biblio-1505415

RESUMO

A constante influência humana em atividades de manejo animal, além de aumentar os custos de produção, torna-se uma adicional fonte geradora de estresse sobre os animais. Nesse sentido, é necessária a busca pelo desenvolvimento de métodos alternativos de acompanhamento, à distância e em tempo real, das condições físicas dos animais, em conjunto com o controle das instalações. Para a identificação da condição de conforto ou estresse calórico dos animais, alguns indicativos podem vir a auxiliar, tais como a temperatura retal (TR), sendo esse um bom indicador da temperatura do núcleo corporal, bem como, a frequência respiratória (FR). Porém, com a crescente preocupação em relação ao bem-estar animal, vários questionamentos são feitos acerca de métodos invasivos, motivando a busca por alternativas à mensuração da TR. Surge então, como variável alternativa, a temperatura da superfície corporal, buscando-se correlacioná-la com a TR e FR. Sendo assim, com essa pesquisa objetivou-se identificar a região mais adequada da superfície corporal dos suínos, em fase de creche, que apresente a melhor correlação com a TR e FR. Para tal, foi conduzido um experimento, dividido em duas etapas: etapa 1) pré-experimento, sendo conduzido com dois animais em câmara climática, variando-se as condições de temperatura e testando-se métodos de fixação de sensores e coleta de dados inicialmente propostos; e etapa 2) experimento principal. Este último foi conduzido em uma câmara climática, com cinco leitões da raça Landrace x Large White, com 30 dias de idade, provenientes de uma mesma ninhada e do mesmo sexo (fêmea). Variaram-se as condições de temperatura no interior da câmara climática de 14°C a 35,5°C, de modo a atingir situações de estresse tanto por frio quanto por calor, sendo calculada a entalpia para os propósitos do presente estudo. [...]


Human constant influence in handling activities, besides raising production costs, becomes another stress source for the animals. In this sense, it becomes necessary the development of alternative methods, that can remotely monitor, in real time, animal/'s physical conditions, together with remote facilities control. In terms of identifying comfort or stressful thermal situations for animals, some indicators can be handy, such as rectal temperature (RT), which is a good indicator of the core body temperature, as well as, the respiratory rate (RR). Although, with the raising concerns about animal welfare, several questions are raised against invasive methods, encouraging the search for alternatives to RT measuring. The determination of body surface temperature values, trying to correlate them to RT and RR, emerges as an alternative. Thus, it/'s aimed, with this research, to identify the most adequate swine body surface region, in nursery phase, which presents better correlation with RT and RR. For that, an experiment was conducted, divided in two stages: stage 1) pre-experiment, being conducted with two animals in a climate chamber, varying temperature conditions and testing sensor fixation and data collection methods previously proposed; and stage 2) main experiment. The last one was conducted in a climate chamber, with five Landrace x Large White piglets, 30 days aged, from the same litter and of the same sex (female). Temperature conditions inside the chamber were varied from 14°C to 35.5°C, attaining stressful situations both for cold and heat, being calculated the enthalpy for this study purposes. The statistical design used was the completely randomized, with one factor only, the ambient enthalpy, in seven levels (31.26; 39.56; 51.12; 59.24; 74.82; 82.96; 94.26 kJ.kg of dry air-1). Repeated measures were taken in 30 minutes intervals, in six different body regions: head (A), shoulder (B), loin (C), ham (D), ear (E) and tympanic (F). [...]


Assuntos
Animais , Bem-Estar do Animal , Suínos , Taxa Respiratória , Temperatura Corporal , Ar Condicionado , Transtornos de Estresse por Calor/veterinária
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