Search results for " harvest"
showing 10 items of 205 documents
Thermal stability of trimeric light-harvesting chlorophyll a/b complex (LHCIIb) in liposomes of thylakoid lipids.
2006
The major light-harvesting chlorophyll a/b complex (LHCIIb) of photosystem (PS) II functions by harvesting light energy and by limiting and balancing the energy flow directed towards the PSI and PSII reaction centers. The complex is predominantly trimeric; however, the monomeric form may play a role in one or several of the regulatory functions of LHCIIb. In this work the dissociation temperature was measured of trimeric LHCIIb isolated from Pisum thylakoids and inserted into liposomes made of various combinations of thylakoid lipids at various protein densities. Dissociation was measured by monitoring a trimer-specific circular dichroism signal in the visible range. The LHCIIb density in t…
Measuring water-use in response to climate change: an analysis of the efficiency of Italian crop production system
2017
Official meteo-climatic statistics show the variability of weather conditions. Their effects on socioeconomic and natural environments should be analyzed in multi-dimensional studies. Among sectors, agriculture is expected to be the most sensitive as well as water resources availability. The aim of our analysis is to measure the performance of Italian regions in crop production by estimating both production technology - including a measure of irrigation water used as input - output elasticities and returns to scale and productive efficiency or technical efficiency where rainfalls and temperatures are proxies of CC conditions in the period 2000-2010 at Italian regional level, using the stoch…
A Battery-Free Smart Sensor Powered with RF Energy
2018
The development of Internet of Things (IoT) infrastructure and applications is stimulating advanced and innovative ideas and solutions, some of which are pushing the limits of state-of-the-art technology. The increasing demand for Wireless Sensor Network (WSN) that must be capable of collecting and sharing data wirelessly while often positioned in places hard to reach and service, motivates engineers to look for innovative energy harvesting and wireless power transfer solutions to implement battery-free sensor nodes. Due to the pervasiveness of RF (Radio Frequency) energy, RF harvesting that can reach out-of-sight places could be a key technology to wirelessly power IoT sensor devices, whic…
A group-based wireless body sensors network using energy harvesting for soccer team monitoring
2016
[EN] In team-based sports, it is difficult to monitor physical state of each athlete during the match. Wearable body sensors with wireless connections allow having low-power and low-size devices, that may use energy harvesting, but with low radio coverage area but the main issue comes from the mobility. This paper presents a wireless body sensors network for soccer team players' monitoring. Each player has a body sensor network that use energy harvesting and each player will be a node in the wireless sensor network. This proposal is based on the zone mobility of the players and their dynamism. It allows knowing the physical state of each player during the whole match. Having fast updates an…
Performance analysis of underlay two-way relay cooperation in cognitive radio networks with energy harvesting
2018
Abstract Cognitive radio and energy harvesting are two important approaches to solve the problem of spectrum scarcity and energy constraint in wireless communications. In this work, we study a two-way relay cooperation scheme in underlay cognitive radio networks (CRNs) with energy harvesting in which two secondary users exchange information via an energy harvesting relay node. Since the relay node collects energy from the received signals and utilizes it to forward the information, the secondary transmission power can be markedly reduced. Therefore the interference of the secondary network to the primary network can be substantially reduced. We derive the outage probability of the secondary…
Context-Aware RF-Energy Harvesting for IoT Networks
2021
Energy Harvesting plays a crucial role in improving the operational lifetime of IoT devices. The deployment of dedicated RF-transmitters helps in sufficient energy propagation to the sensor nodes of IoT networks. Also, energy harvesting using the deployment of such RF-transmitters is a challenging issue. In this work, two methods are proposed for the optimal placement of RF-transmitters for efficient energy harvesting in wireless sensor networks. The proposed context-aware RF-energy harvesting considers different network performance parameters such as energy-hole information, and data routing information. RF-transmitter deployment is achieved using network connectivity information in the fi…
Evaluation of an Optical Energy Harvester for SHM Application
2019
Abstract In this paper a preliminary study on an array configuration of rectified optical nanoantennas for energy harvesting application is proposed. Currently, the major impediments for the use of the rectified optical nanoantenna known as rectenna are the relatively low conversion efficiency and low power transfer to the load, both of them caused mainly by the mismatch between the impedance of the rectifier (several kilo ohms) and that of the antenna (hundreds of ohm). For this reason, the design of the array represents a crucial point to obtain the maximum energy transfer from the rectenna to the load, represented as a typical DC/DC boost power converter, and modeled by an equivalent inp…
Rainwater harvesting in urban areas of developed countries. The state of the art (1980-2017)
2020
Many urban areas suffer from water scarcity although paradoxically, a local source such as rainwater is mostly treated as a risk rather than a valuable resource. This change of paradigm is included in the 'integrated water resources management' and 'demand management' approach. The aim of this research is to identify and analyse studies that explore subject matters concerning rainwater in the integrated management systems of water resources into developed countries. The research methodology consisted in a literature review (from the 1980s to 2017) of territorial studies that examine rainwater harvesting in urban areas of the developed countries. To this end, a bibliometric analysis has been…
Rapid evaluation of ammonium in different rain events minimizing needed volume by a cost-effective and sustainable PDMS supported solid sensor.
2020
Abstract The presence of ammonium ion in rainwater is due to atmospheric processes which involve its scavenging from gas phase and particulate matter. The fractionated samplings of rainwater can provide information about these processes and their potential sources. However, only a low sample volume may be available, which constrained the analysis in general and more particularly in situ mode. For minimizing this limitation, this work proposes a polydimethylsiloxane (PDMS)-salicylate sensor that produces a color change. The embedding of solid reagents into PDMS was optimized. Good analytical characteristics (analysis time of 10 min, sample volume of 500 μL, limit of detection 0.03 μgmL−1) we…
The sustainability of olive orchard planting management for different harvesting techniques: An integrated methodology
2019
Abstract The globalization of the olive oil market has caused greater competitiveness in terms of olive oil quality and production costs and the main countries interested in olive growing, have introduced efficient planting design and horticultural techniques in order to meet these requirements. In this paper the sustainability of olive orchard planting management for different olive fruit-harvesting methods has been assessed on the basis of the data gathered by the Geographic Information System and processed using a Multi-Criteria Decision Making Analysis. In particular, three different agronomic scenarios have been analyzed and a specific cultivar has been considered in order to ensure th…