Robust, wearable, on-body antenna relying on half mode substrate integrated waveguide techniques

A compact, robust, wearable antenna for body-worn applications in the 2.4 GHz Industrial Medical and Scientific band is designed, fabricated and tested. This novel compact textile cavity backed slot antenna combines a half-mode substrate integrated waveguide topology with an additional row of shorting vias for miniaturization. Excellent free space performance is achieved with a measured 4.6 % impedance bandwidth, maximal gain of 4.7 dBi and radiation efficiency of 81.3 %. On-body measurements reveal minimal frequency detuning when the antenna is worn by a test subject as well as a negligible impedance bandwidth reduction to 4.5 %. The low calculated Specific Absorption Rate of 0.51 W/kg averaged over 1 g of tissue demonstrates high antenna body isolation. Therefore, this design is an attractive option as antenna in smart textile systems

Compact cavity-backed antenna on textile in substrate integrated waveguide (SIW) technology

In this paper a folded cavity-backed patch antenna implemented in substrate integrated waveguide (SIW) technology is presented. The antenna has been designed to operate at 2.45 GHz, in the industrial, scientific and medical (ISM) frequency band, and a textile substrate has been adopted for the realization of the component. This topology of textile antenna could be useful for the monitoring of the activities of rescue workers in emergency situations such as the localization of firefighters, and the communication in critical operations. The proposed antenna has been experimentally verified: the response of the antenna exhibits a small frequency shift, caused by a discrepancy between the nominal and the real value of electrical permittivity of the textile substrate. The measured radiation characteristics of the antenna show a good agreement with simulations, and a measured radiation efficiency of approximately 70%

Circularly-polarised cavity-backed wearable antenna in SIW technology

This study presents a circularly-polarised substrate-integrated waveguide (SIW) antenna implemented using a textile substrate and operating at 2.45GHz, in the industrial, scientific, and medical frequency band. The antenna topology is based on a folded cavity with an annular ring as a radiating element, and it permits to obtain compact size and low sensitivity to the environment, without deteriorating the radiating performance. These characteristics, together with the choice of adopting a textile substrate, make the SIW antenna suitable for the integration in wearable systems for body-centric applications. The electromagnetic performance of the proposed antenna achieved in simulations was verified through the measurement of the device in an anechoic chamber. The circularly-polarised antenna exhibits a maximum gain of 6.5dBi, a radiation efficiency of 73% and a very high front-to-back ratio

The next generation textile antennas based on substrate integrated waveguide technology

Textile antennas for body-worn applications have some very specific requirements and needs. From an electrical engineer's point of view, good radiation characteristics and impedance matching to the active electronics are important. From the wearer's perspective, the antenna should be unobtrusively integrated into the clothing, and the smart textile comfortable to wear. New techniques offer the potential to fulfill these different needs. One new approach consists of applying metalized eyelets to implement substrate integrated waveguide technology on textile materials. This results in high-performance on-body antennas with excellent behavior in close proximity of the human body. Two realizations are discussed: a wideband design and a miniaturized half mode substrate integrated waveguide dual-band design. Both yield excellent free-space and on-body performance, and superb antenna-body isolation, automatically resulting in very robust characteristics when deployed on-body

Wearable textile antenna in substrate integrated waveguide technology

A novel wearable substrate integrated waveguide antenna fabricated entirely from textile materials is presented. The cavity-backed slot antenna operates in the 2.45 GHz industrial, scientific and medical band, for short range communication between rescue workers. A prototype of the antenna was fabricated and tested: good performance was obtained in terms of input matching and radiation pattern. Moreover, measurements performed on the antenna after bending and integration into clothing indicate high robustness against deformation and low influence of the human body on antenna performance, making the design well-suited for on-body use

La fisica tra la scuola secondaria e l’università. Riflessioni e orientamenti

L’università ha da sempre una porta aperta verso il mondo della scuola secondaria, il che ne fa un interlocutore privilegiato in continua e mutua interazione, sia per la formazione degli insegnanti (dal punto di vista contenutistico e metodologico), sia per la platea di studenti che quella porta la attraverseranno per continuare il loro cammino di apprendimento. Spesso non sono solo i soggetti (insegnanti e studenti) ad essere parte dell’interazione, ma anche gli oggetti (tematiche e metodologie), in particolare per le materie STEM (Science, Technology, Engineering, Mathematics); in tal caso nel passaggio dalla scuola all’università lo studente ritrova la materia che ha affrontato sino a qualche mese prima, talvolta proseguendola con uno sviluppo tematico successivo e talvolta affrontando la stessa tematica con diversa profondità. Questo è particolarmente vero nel caso della fisica, in cui le macro-tematiche classiche principali (la meccanica, la termodinamica, l’elettromagnetismo, l’ottica, cenni alla fisica moderna) trovano spazio comune nelle due realtà formative

An extensive questionnaire about Metacognition during Emergency Remote Teaching involving more than 3000 engineering students

By 11 March 2020, the phrase “COVID-19” had officially entered everyday life across most of the word. Each level of education suddenly faced new changes and new challenges. Emergency remote teaching became widespread, and new methodologies to deliver classes and courses were adopted by educational institutions. In this paper, we focus on the impact of the remote learning experience of engineering students enrolled at the Politecnico di Milano. The subjects were recruited from all engineering courses from the first to the fifth year and were asked to complete a multidimensional survey. The survey featured 66 items regarding the participants’ perceptions of the challenges of emergency remote teaching compared with pre-COVID-19 in-person teaching. The questionnaire addressed six dimensions: the organization of emergency remote teaching, subjective well-being, metacognition, self-efficacy, identity, and socio-demographic information. In this paper, we describe the entire survey and discuss a preliminary analysis. Using Cronbach’s alpha test, a confirmatory factor analysis, and the t-test, we performed a more in-depth analysis concerning the outcomes of metacognition and self-efficacy. The data analysis suggested a small, unexpected change in the metacognition strategies. The students, in some regards, improved their learning strategies. Some other answers underlined their appreciation of the courses’ organization and the lack of relationships with their peers and teachers

Mora Romagnola Pig

Mora Romagnola breed, one of the Italian local pig breeds, owes its name to its colour, dark brown tending to black. Currently 31 farms are registered in the herdbook started in 2001 with about 270 breeding females and 67 boars. During the 1990s, only 18 animals were left, all concentrated in one single farm. The breed was investigated within the H2020 project TREASURE, and a collection and review of available literature data on reproductive and productive traits of Mora Romagnola pig breed were carried out. The average age of sows at first parturition was 22 months, whereas age at culling was 58 months. On average, Mora Romagnola pig breed has 8.0 piglets per parity with 1.4 parities per year. Slaughter weight was on average 163 kg with a dressing yield of 80%. Few information is available for meat quality traits. Although studies on Mora Romagnola pig are scarce, the current review gives the first insight into this local pig breed

Apulo-Calabrese Pig

The aim of the present chapter is to present history and current status of Apulo-Calabrese pig breed, one of the local pig breeds investigated in the project TREASURE. Apulo-Calabrese breed is one of the Italian autochthonous pig breeds. Its origin dates back to the Roman times, but it suffered a drastic decline during the past century and the recovery started in the 1990s. A herd book for this breed was established in 2001, but its performances and products are practically untapped. There are 45 registered farms with around 500 breeding sows and 100 boars. Apulo-Calabrese pig is characterised by black coat colour. On average sows of Apulo-Calabrese pig breed have 1.7 litters per year with 6.9 piglets. Regarding growth performances, the potential of Apulo-Calabrese pigs in ad libitum conditions of feeding is high (≈762 g/day in middle fattening stage) although information on feed intake and feed nutritional value was scarce, which limits the evaluation of growth potential. Data on body composition, carcass traits and meat and fat quality are scarce. The present review gives a first insight into this local pig breed

Sarda Pig

Sarda pig breed (a.k.a. Suino Sardo) is a local breed from Sardinia Island (Italy) with its ancestors dating back to the Nuragic period. It is the most recent breed interested by a conservation programme among the six Italian autochthonous pig breeds investigated by the H2020 project TREASURE and could be considered untapped in terms of information on its performances and products. Thirteen farms were registered at the last census (2015) including sixty-one breeding sows and twenty boars. It is a small size breed with black, grey, tawny or spotted coat colour. On average, age at parturition is 15.7 months, with 1.6 litters per year and 7.8 piglets per parity. Average piglet mortality is rather high in the considered studies (16.1%). The average daily gain for Sarda pig within the considered studies was 423 g/day. On average, daily feed intake in the overall fattening stage was 2.3 kg/day. Sarda pigs were slaughtered at approximately 686 days of age, at an average live weight of 193 kg. Sporadic information is available for meat quality traits. Although studies on Sarda pig are scarce, the current review gives the first insight into this local pig breed