Search Results (6)

In this paper, an overview of the potentiality of Arduino boards is presented, together with a description of the Arduino interfacing with light multi-sensors. These sensors can be arranged in linear arrays or in a matrix configuration (CCD or CMOS type cameras) and are equipped with tens, hundreds, or even thousands of elements whose sizes range from a few microns to tens of microns. The use of these sensors requires electronics that have high time accuracy, since they work through regular pulses sent by an external source and, furthermore, have the ability to digitize and store voltage signals precisely and quickly. We show that, with the appropriate settings, a simple Arduino board can handle both 1D and 2D optical sensors. Finally, we describe a solar compass made with such a board coupled to one of the tested optical array sensors that is capable of providing the north direction with a very high degree of accuracy. Full article

Under the conditions of climate change and energy crisis stemming from the COVID-19 pandemic and the embargo on the supply of raw materials from Russia, high hopes are attached to the development of renewable energy in terms of meeting energy needs. Still, renewable energy has some drawbacks too. In the most dynamically growing solar and wind energy industries, the main problems that are indicated include this energy storage and ensuring the security of supplies. These are supposed to be solved by the digital transformation of renewable power generation plus the entry of market players that implement digital business models in renewable energy. The purpose of the article is to identify a framework “digital compass” of business models in renewable energy within a group of solar and wind energy start-ups, operating in energy storage and supply industries. At the base of this study there were: digital technologies, customer orientation, delivery of value and revenue stream. The research algorithm applied here enabled the identification and classification of startup business models based on secondary data using R software. The results show that the identified startups implement digital business models to a minor extent. Startups dealing with solar energy storage stand out in a quite positive manner. The low digital attractiveness of investing in wind energy storage and supply (which, to a smaller extent applies to solar energy), is also indicated the investment preferences of big-tech. Thus, the future of the digital transformation of these industries should be related to regulatory changes rather than technological ones. Full article

Background: Health extension workers (HEWs) have substantial inputs to reduce maternal and newborn morbidity and mortality in Ethiopia. However, their perceptions and experiences were not well understood. Therefore, this study aimed to explore their perceptions and experiences on facilitators and barriers to maternal and newborn health services in Ethiopia. Methods: A descriptive qualitative study was conducted from 8–28 April 2021 in Oromia, Amhara and Southern Nation, Nationality, and People’s Regional State of Ethiopia. Focused group discussions were made with purposively selected 60 HEWs. The data were transcribed verbatim and translated into English. An inductive thematic analysis was carried out using Atlas ti.7.1. The findings were presented in major themes, categories, and sub-categories with supporting quote(s). Results: The findings were categorized into two major themes (i.e., facilitators and barriers) and seven sub-themes. Community-related facilitators encompass awareness and behavior at the individual, family, and community. Significant others such as traditional birth attendants, religious leaders, women developmental armies, and kebele chairman substantially contributed to service utilization. Availability/access to infrastructures such as telephone, transportation services, and solar energy systems facilitated the service utilization. Furthermore, health facility-related facilitators include the availability of HEWs; free services; supervision and monitoring; maternity waiting rooms; and access to ambulance services. Maternal and newborn health services were affected by community-related barriers (i.e., distance, topography, religious and socio-cultural beliefs/practices, unpleasant rumors, etc.,), health facility-related barriers (i.e., health worker’s behaviors; lack of logistics; lack of adequate ambulance service, and placement and quality of health post), and infrastructure (i.e., lack or poor quality of road and lack of water). Conclusions: The HEWs perceived and experienced a wide range of facilitators and barriers that affected maternal and newborn health services. The study findings warrant that there was a disparity in behavioral factors (awareness, beliefs, and behaviors) among community members, including pregnant women. This underscores the need to design health education programs and conduct social and behavioral change communication interventions to address individuals, families, and the broader community to enhance maternal and newborn health service utilization. On the other hand, the health sector should put into practice the available strategies, and health workers provide services with empathy, compassion, and respect. Full article

Understanding the orientation behavior and capabilities in early life history (ELH) of fishes is critical for studying their dispersal but has, surprisingly, never been tested in any pelagic species. We here investigate the ontogeny of orientation and swimming abilities of the pelagic Coryphaena hippurus Linnaeus, 1758 larvae, hereafter mahi-mahi, through their ELH stages using the Drifting In Situ Chamber (DISC) in a laboratory setup. The DISC was deployed in a large (3 m³) circular aquarium in order to control the stimulus perceived by the fish and to identify behavioral response at the individual, developmental stage, and population levels. A total of 79 individual ranging from 7 to 23 days post hatch and from preflexion to early juvenile stages were exposed to a directional light mimicking the sun’s position. Orientation towards the light direction was tested by switching the light by 180° among trials. To compare the orientation among development stages, we scaled the directionality by the swimming ability, therein defined as “directionality competence”. The results show that while mahi-mahi directionality competence increases through ontogeny, they acquire a positive and directional phototaxis behavior at the flexion stage. This potential solar orientation is kept through the early juvenile stage. Mahi-mahi may thus be able to use the sun as a compass in the open ocean as observed in the larval stages of demersal species seeking for settlement habitats. This ability notably develops before the improvement of their swimming capabilities, suggesting that early orientation—even at micro-scale—and swimming capabilities may be equally important for the survival of the ELH stages of pelagic species. Full article

The UltraViolet and infrared Sensors at high Quantum efficiency onboard a small SATellite (UVSQ-SAT) mission aims to demonstrate pioneering technologies for broadband measurement of the Earth’s radiation budget (ERB) and solar spectral irradiance (SSI) in the Herzberg continuum (200–242 nm) using high quantum efficiency ultraviolet and infrared sensors. This research and innovation mission has been initiated by the University of Versailles Saint-Quentin-en-Yvelines (UVSQ) with the support of the International Satellite Program in Research and Education (INSPIRE). The motivation of the UVSQ-SAT mission is to experiment miniaturized remote sensing sensors that could be used in the multi-point observation of Essential Climate Variables (ECV) by a small satellite constellation. UVSQ-SAT represents the first step in this ambitious satellite constellation project which is currently under development under the responsibility of the Laboratory Atmospheres, Environments, Space Observations (LATMOS), with the UVSQ-SAT CubeSat launch planned for 2020/2021. The UVSQ-SAT scientific payload consists of twelve miniaturized thermopile-based radiation sensors for monitoring incoming solar radiation and outgoing terrestrial radiation, four photodiodes that benefit from the intrinsic advantages of Ga ${}_2$ O ${}_3$ alloy-based sensors made by pulsed laser deposition for measuring solar UV spectral irradiance, and a new three-axis accelerometer/gyroscope/compass for satellite attitude estimation. We present here the scientific objectives of the UVSQ-SAT mission along the concepts and properties of the CubeSat platform and its payload. We also present the results of a numerical simulation study on the spatial reconstruction of the Earth’s radiation budget, on a geographical grid of 1 $°$ × 1 $°$ degree latitude-longitude, that could be achieved with UVSQ-SAT for different observation periods. Full article

Animals, such as Savannah sparrows and North American monarch butterflies, are able to obtain compass information from skylight polarization patterns to help them navigate effectively and robustly. Inspired by excellent navigation ability of animals, this paper proposes a novel image-based polarized light compass, which has the advantages of having a small size and being light weight. Firstly, the polarized light compass, which is composed of a Charge Coupled Device (CCD) camera, a pixelated polarizer array and a wide-angle lens, is introduced. Secondly, the measurement method of a skylight polarization pattern and the orientation method based on a single scattering Rayleigh model are presented. Thirdly, the error model of the sensor, mainly including the response error of CCD pixels and the installation error of the pixelated polarizer, is established. A calibration method based on iterative least squares estimation is proposed. In the outdoor environment, the skylight polarization pattern can be measured in real time by our sensor. The orientation accuracy of the sensor increases with the decrease of the solar elevation angle, and the standard deviation of orientation error is $0.{15}^{\circ }$ at sunset. Results of outdoor experiments show that the proposed polarization navigation sensor can be used for outdoor autonomous navigation. Full article