Current Issue : October - December Volume : 2019 Issue Number : 4 Articles : 5 Articles
Continuous monitoring of breathing activity plays a major role in detecting and classifying\na breathing abnormality. This work aims to facilitate detection of abnormal breathing syndromes,\nincluding tachypnea, bradypnea, central apnea, and irregular breathing by tracking of thorax\nmovement resulting from respiratory rhythms based on ultrasonic radar detection. This paper\nproposes a non-contact, non-invasive, low cost, low power consumption, portable, and precise\nsystem for simultaneous monitoring of normal and abnormal breathing activity in real-time using an\nultrasonic PING sensor and microcontroller PIC18F452. Moreover, the obtained abnormal breathing\nsyndrome is reported to the concerned physicianâ??s mobile telephone through a global system for\nmobile communication (GSM) modem to handle the case depending on the patientâ??s emergency\ncondition. In addition, the power consumption of the proposed monitoring system is reduced\nvia a duty cycle using an energy-efficient sleep/wake scheme. Experiments were conducted on\n12 participants without any physical contact at different distances of 0.5, 1, 2, and 3 m and the\nbreathing rates measured with the proposed system were then compared with those measured by a\npiezo respiratory belt transducer. The experimental results illustrate the feasibility of the proposed\nsystem to extract breathing rate and detect the related abnormal breathing syndromes with a high\ndegree of agreement, strong correlation coefficient, and low error ratio. The results also showed that\nthe total current consumption of the proposed monitoring system based on the sleep/wake scheme\nwas 6.936 mA compared to 321.75 mA when the traditional operation was used instead. Consequently,\nthis led to a 97.8% of power savings and extended the battery life time from 8 h to approximately\n370 h. The proposed monitoring system could be used in both clinical and home settings....
In recent decades, micro and nanoscale technologies have become cutting-edge frontiers\nin material science and device developments. This worldwide trend has induced further\nimprovements in actuator production with enhanced performance. A main role has been played by\nnanostructured carbon-based materials, i.e., carbon nanotubes and graphene, due to their intrinsic\nproperties and easy functionalization. Moreover, the nanoscale decoration of these materials has led\nto the design of doped and decorated carbon-based devices effectively used as actuators\nincorporating metals and metal-based structures. This review provides an overview and discussion\nof the overall process for producing AC actuators using nanostructured, doped, and decorated\ncarbon materials. It highlights the differences and common aspects that make carbon materials one\nof the most promising resources in the field of actuators....
As a key enabler for future aviation technology, the use of servo electromechanical actuation\noffers new opportunities to transition innovative structural concepts, such as biomimicry morphing\nstructures, from basic research to new commercial aircraft applications. In this paper, the authors\naddress actuator integration aspects of a wing shape-changing flight surface capable of adaptively\nenhancing aircraft aerodynamic performance and reducing critical wing structural loads. The research\nwas collocated within the Clean Sky 2 Regional Aircraft Demonstration Platform (IADP) and aimed\nat developing an adaptive winglet concept for green regional aircraft. Finite Element-based tools\nwere employed for the structural design of the adaptive device characterized by two independent\nmovable tabs completely integrated with a linear direct-drive actuation. The structural design process\nwas addressed in compliance with the airworthiness needs posed by the implementation of regional\nairplanes. Such a load control system requires very demanding actuation performance and sucient\noperational reliability to operate on the applicable flight load envelope. These requirements were met\nby a very compact direct-drive actuator design in which the ball recirculation device was integrated\nwithin the screw shaft. Focus was also given to the power-off electric brake necessary to block\nthe structure in a certain position and dynamically brake the moveable surface to follow a certain\ncommand position during operation. Both the winglet layout static and dynamic robustness were\nverified by means of linear stress computations at the most critical conditions and normal mode\nanalyses, respectively, with and without including the integrated actuator system....
This work describes the use of a paper substrate for electro-optical detection of toxic\nhydrogen sulfide (H2S) gas. For electrical detection, a chemiresistive type of gas sensor was\ndeveloped. Ultrathin gold film electrodes (UTGFE) were produced by physical vapor deposition of\ngold on nanostructured latex-coated paper substrate. The gas-sensing film was deposited on the\nelectrodes by inkjet printing. The sensing films were characterized by atomic force microscopy, X-ray\nphotoelectron spectroscopy and conductometry. The sensing films showed more than seven\norders of magnitude change in resistance when exposed to as low as 1 part per million (ppm) H2S\ngas at room temperature. Besides resistive response, the change in color of the sensing films was\nstudied on a paper substrate, both as a function of print density of the sensing material and H2S\nconcentration. For quantification of the analyte the red, green and blue color deconvolution was\nperformed on the pictures of the paper strip indicator using an open source software. A clear\nresponse was obtained from the blue channel. The inexpensive disposable color strips produced on\nthe paper substrate can be used for qualitative and quantitative detection (as low as 1.5 ppm) of H2S\ngas....
This article reports that it is possible to make multifunctional sensing devices with ZnO\ninfiltrated polymers while the sensing interactions could occur throughout the polymer. As such,\nwe find that infiltrated devices with SU-8 polymer can result in highly sensitive UV sensors. Mesh\ndielectric core devices were found to make sensitive gas sensors with a better than 5 ppm sensitivity\nfor formaldehyde and NO2. A new type of p-n junction device is further demonstrated that is\nsensitive to UV illumination, thus making it an enhanced UV sensor. Sensing devices relying on\nvolume interactions, such as light absorption, can significantly benefit from the infiltrated polymer.\nIn contrast, devices that rely on surface interactions, such as gas sensors, do not gain performance\nin any significant way with or without the infiltrated polymer....
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