Simplified Approach to Detect Dielectric Constant Using a Low-Cost Microfluidic Quarter Mode Substrate-Integrated Waveguide

Liquid materials’ characterization using commercial probes and radio frequency techniques is expensive and complex. This study proposes a compact and cost-effective radio frequency sensor system to measure the dielectric constant using a three-material calibration. The simplified approach measures reflection coefficient magnitudes for all four materials rather than the complex values in conventional permittivity detection systems. We employ a sensor module based on a circular substrate-integrated waveguide with measured unloaded quality factor = 910 to ensure measurement reliability. Miniaturized quarter-mode substrate-integrated waveguide resonators are integrated with four microfluidic channels containing three known materials and one unknown analyte. Step-wise measurement and linearity ensures maximum 4% error for the dielectric constant compared with results obtained using a high-performance commercial product.

Development of Radio-Frequency Sensor Wake-Up with Unmanned Aerial Vehicles as an Aerial Gateway

The advent of autonomous navigation, positioning, and general robotics technologies has enabled the improvement of small to miniature-sized unmanned aerial vehicles (UAVs, or ‘drones’) and their wide uses in engineering practice. Recent research endeavors further envision a systematic integration of aerial drones and traditional contact-based or ground-based sensors, leading to an aerial–ground wireless sensor network (AG-WSN), in which the UAV serves as both a gateway besides and a remote sensing platform. This paper serves two goals. First, we will review the recent development in architecture, design, and algorithms related to UAVs as a gateway and particularly illustrate its nature in realizing an opportunistic sensing network. Second, recognizing the opportunistic sensing need, we further aim to focus on achieving energy efficiency through developing an active radio frequency (RF)-based wake-up mechanism for aerial–ground data transmission. To prove the effectiveness of energy efficiency, several sensor wake-up solutions are physically implemented and evaluated. The results show that the RF-based wake-up mechanism can potentially save more than 98.4% of the energy that the traditional duty-cycle method would otherwise consume, and 96.8% if an infrared-receiver method is used.

A Small Radio Frequency Sensor for Microwave Tumor Ablation

This paper presents a small radio frequency sensor namely multi-slot antenna for liver tumor ablation at microwave spectrum. A computer simulation model was developed to validate the proposed antenna. The authors tested the proposed antenna on pig liver tissue samples. Both simulation and experimental results showed that the proposed multi-slot antenna has the potential for liver cancer treatment in the future.

Design and Fabrication of a BiCMOS Dielectric Sensor for Viscosity Measurements: A Possible Solution for Early Detection of COPD

The viscosity variation of sputum is a common symptom of the progression of Chronic Obstructive Pulmonary Disease (COPD). Since the hydration of the sputum defines its viscosity level, dielectric sensors could be used for the characterization of sputum samples collected from patients for early diagnosis of COPD. In this work, a CMOS-based dielectric sensor for the real-time monitoring of sputum viscosity was designed and fabricated. A proper packaging for the ESD-protection and short-circuit prevention of the sensor was developed. The performance evaluation results show that the radio frequency sensor is capable of measuring dielectric constant of biofluids with an accuracy of 4.17%. Integration of this sensor into a portable system will result in a hand-held device capable of measuring viscosity of sputum samples of COPD-patients for diagnostic purposes.

Development of A Radio-Frequency Sensor Wake-up Method for Wireless Aerial-Ground Sensing

Energy efficiency in wireless sensing networks (WSN) is the last-mile challenge when deploying a WSN for field-based monitoring task to environmentally hard-access, remote, and geospatial large or complex spaces. In this paper, we propose a novel aerial-ground and energy efficient sensing network for meeting the need of geospatial field monitoring by using an aerial UAV as the mobile gateway to wireless sensor nodes in the ground (or in ground structures). Then the focus of this paper is on achieving energy efficiency for ground sensor nodes. In this paper, the authors develop an active radio-frequency (RF) based wake-up mechanism for data transmission in the aerial-ground sensing network. To prove the energy efficiency, several sensor wake-up solutions are physically implemented and evaluated. The results show that the RF-based wake-up mechanism can potentially save more than 98.4% of the energy that the traditional duty-cycle method would otherwise consume, and 96.8% if an infrared-receiver method is used.

Method of the monitoring illegal chopping tree with use RFID-device and WSN-network

В статье приводится возможность использования радиочастотных сенсоров для предотвращения незаконных рубок деревьев. Такие рубки происходят периодически и тенденций к снижению не наблюдается. Исследования, проводимые в Уральском государственном лесотехническом университете, показали следующее результаты. Только сенсоры, установленные с лесу, способны своевременно контролировать ситуацию о незаконных рубках древесины и многие другие факторы, например: лесные пожары, логистику перемещения лесоматериалов, таксационные исследования дистанционно. Объектом исследования является участок в лесопарке им. Лесоводов России (г. Екатеринбург). Инструментом исследования являются радиочастотные устройства, объединенные в беспроводную сенсорную сеть (WSN). Исследованы звуковые спектральные характеристики бензопил Тайга и Shtil. Представленная методика разработана на основе анализа звуков леса и выделения спектра работы пильных устройств (например, цепных), издающих звук отличных от шума ветра и шелеста листьев. Также исследовали шум работающих агрегатов с бензиновыми и дизельными двигателями. В приведенных спектральных характеристиках выделены, по определенным признакам, характерные критерии для сортировки участков звуковой последовательности фона. Результаты экспериментальных исследований подтверждают, что звук работающей бензопилы слышен в радиусе 500–700 м. Выявлено влияние рельефа и погодных условий на дальность распространения звука бензопилы. Звуковой сигнал анализировался методом Фурье для динамического и временного масштабирования. Звуковые характеристики бензопилы без нагрузки и при пилении отличаются, поэтому предложена коррекция длины волны. Это необходимо для выбора аналого-цифрового преобразователя (АЦП) при проектировании сенсоров контроля незаконной рубки. The possibility of the use radio-frequency sensor happens to In article for prevention illegal chopping tree. Such choppings occur seasonly and trend to reduction does not exist. The Studies conducted in Ural State Forest Engineering University, have shown the following results. That only sensors, set up with wood, capable in good time to check the situation with illegal chopping tree, but also many other factors, for instance: wildfires, logistics of the displacement lumber, estimation studies remote. The Object of the study is an area in wood-park Specialist in forestry to Russia (cit.Ekaterinburg). The Instrument of the study are an radio-frequency device, united in wireless sensor network (WSN). The Explored sound spectral features chain saw with motor Taiga and Shtil. Presented methods is designed on base of the analysis sound wood and separations of the spectrum of the work saw-device (for instance: chain), publishing sound different from noise winds and rustle sheet. Also researched the noise working unit with gasoline and diesel engine. In brought spectral feature are chosen, on determined sign, typical criteria for sorting area to sound sequence of the background. Results of the experimental studies confirm that sound working chain saw with motor heard in radius 500–700 m are Revealled influence of the relief and weather conditions on range of the spreading the sound chain saw with motor. The Bleep was analysed by method Furie, for dynamic and temporary scaling. The Sound features chain saw with motor without load and when sawing differ so a correction wavelength is offered. This required for choice of the analog-to-digital converter (ADC) when designing sensor checking the illegal chopping.

Diesel Particulate Filter-Related Fuel Efficiency Improvements Using Biodiesel Blends in Conjunction With Advanced Aftertreatment Sensing and Controls

It is well known that biodiesel may reduce engine-out particulate matter (PM) emissions and result in PM which has more favorable oxidation characteristics relative to PM derived solely from petroleum diesel. This study investigated the use of neat biodiesel, as well as blends, with a light-duty diesel engine equipped with a catalyzed diesel particulate filter (DPF) and radio frequency particulate filter sensor. The results show a reduction in engine-out PM emissions with increasing biodiesel blend levels and a corresponding increase in the duration between DPF regenerations. In situ measurements of the PM oxidation rates on the DPF using the radio frequency sensor further indicated more rapid oxidation of the biodiesel-derived PM with lower light-off temperatures relative to the petroleum-derived PM. The conclusions indicate considerable potential to extend DPF regeneration intervals and decrease regeneration duration when biodiesel blends are used in conjunction with advanced DPF sensing and control systems, thereby reducing the DPF-related fuel consumption.