Search results for "PV"
showing 10 items of 704 documents
Knowledge, opinions and attitudes of Italian mothers towards HPV vaccination and Pap test
2015
Aim This study evaluated the knowledge and attitudes of Italian mothers – whose daughters had been vaccinated in 2012 – towards primary (anti-HPV vaccination) and secondary (Pap test screening) cervical cancer prevention, as well as sources of information and mother-daughter communication on health issues. Methods The survey – part of a multicenter study carried out in 4 Italian cities (Ferrara, Rome, Cassino and Palermo) – was conducted through self-administered questionnaires. The first univariate analysis evaluated differences between mothers of under-18s and over-18s relative to knowledge and attitudes on HPV vaccination and Pap test. The second univariate analysis evaluated differences…
A comparison of different one-diode models for the representation of I–V characteristic of a PV cell
2014
Predictive performance tools are an important factor in the success of any new technology because they permit demonstration of whether a system will be efficient and economically feasible. A reliable predictive tool should allow the designer to optimise system performance and to maximise the cost effectiveness of a system prior to installation. This article discusses the five main parametric models for photovoltaic (PV) systems available in the literature. The current–voltage characteristics of a photovoltaic module can be reproduced modelling the PV panel as an equivalent electrical circuit made of linear and non-linear components. The parameters describing such components are directly rel…
Net-zero energy technical shelter
2011
Technical shelter for storing electronic and technical equipments has high indoor heat dissipation rate, and cooling load exists almost all year around. Energy consumption of cooling system takes majority of entire energy use. Our project aims in reducing the energy consumption by proper design of building envelop and optimal control of cooling system. Both experimental measurements and computer simulation are carried out to analyze the indoor climate and energy performance of technical shelter in different conditions. The experiments are made on a standard technical shelter. Vertical temperature gradient and air flow rate are measured by thermocouples and tracer gas technology. Energy bala…
A new Scheme for RPL to handle Mobility in Wireless Sensor Networks
2017
Mobile wireless sensor networks (WSNs) are characterised by dynamic changes in the network topology leading to route breaks and disconnections. The IPv6 routing protocol for low power and lossy networks (RPL), which has become a standard, uses the Trickle timer algorithm to handle changes in the network topology. However, neither RPL nor Trickle timer are well adapted to mobility. This paper investigates the problem of supporting mobility when using RPL. It enhances RPL to fit with sensors' mobility by studying two cases. Firstly, it proposes to modify RPL in order to fit with a dynamic and hybrid topology in the context of medical applications. Secondly, it investigates a more general case…
An intrusion detection system for selective forwarding attack in IPv6-based mobile WSNs
2017
Selective forwarding attack is considered among the most dangerous attack in wireless sensor networks, particularly in mobile environment. The attackers compromise legitimate nodes and selectively drop some packets. In addition to that, the movement of some nodes increases link failures, collisions and packet loss. So, it will be more difficult to detect malicious nodes from legitimates ones. This paper focuses on detecting selective forwarding attackers in IPv6-based mobile wireless sensor networks when the standardized IPv6 Routing Protocol for Low Power and Lossy Networks (RPL) is used. Contrarily to previous works which propose solutions to detect selective forwarding attack in static w…
An adaptive timer for RPL to handle mobility in wireless sensor networks
2016
This paper focuses on the performance of wireless sensor networks characterized by a hybrid topology composed of mobile and static sensor nodes. The Routing Protocol for Low power and lossy networks (RPL), which is standardized as an IPv6 routing protocol for low power and lossy networks, uses the trickle timer algorithm to handle changes in the network topology. However, this algorithm is not well adapted to dynamic environments. This paper enhances the trickle timer in order to fit with mobility requirements. Most of previous works have improved this algorithm without considering the random movement of nodes. In this work, the proposed timer algorithm takes into consideration the random t…
Valdemāra Murevska 60. gadu jubilejas pasākums ražošanas apvienībā "Radiotehnika": 14 fotogrāfijas
1971
Valdemārs Murevskis (1911-1989) no 1946.g. strādāja rūpnīcā „Radiotehnika” (pazīstama arī kā RRR, A.S. Popova Rīgas radiorūpnīca) – sākumā par vecāko meistaru virpotavas-frēzēšanas cehā, vēlāk – par vecāko inženieri un par Akustikas sektora priekšnieku rūpnīcas Centrālajā laboratorijā. Atrisinājis daudzus sarežģītus tehnoloģiskus uzdevumus, saņēmis vairākas patentapliecības. V. Murevskim piešķirts Goda radista (1955) un Latvijas PSR Nopelniem bagātā zinātnes un tehnikas darbinieka goda nosaukums (1964).
Eclogites and garnet pyroxenites: Similarities and differences
2010
Eclogites and garnet pyroxenites are genetically linked to basaltic precursors. Traditionally garnet pyroxenites are linked to fractionation of basaltic Magmas Over a range of mantle pressures and more recently they have been implicated in the genesis of ocean islands. in contrast eclogites are linked to the subduction of slab basalt and gabbro precursors which may be hydrothermally altered. Recently this subduction paradigm has been questioned. We present mineralogical, trace element and O isotopic data for eclogites and garnet pyroxenites that reveal some similarities but also important chemical and isotopic differences that support a distinct provenance (i.e., age and process). Continent…
Metālisko un heterogēno nanodaļiņu iegūšana ar lāzera ablācijas metodi šķidrumā
2017
Metāliskas kodola-apvalka nanodaļiņas ir jauns inovatīvs un perspektīvs materiālu veids. To izmantošanas iespējas ir plašas, ieskaitot pielietojumus triboloģijā un ūdens elektrolīzē. Īpaši prioritārais nanodaļiņu iegūšanas ar lāzera starojuma palīdzību veids ir impulsa lāzera ablācijas metode. Darbā tiek izpētīta metālisko mērķu lāzera ablācija šķidrumos, kā arī apskatīti lāzera ablācijas metodes fizikālie pamati. Šīs metodes priekšrocības ir, ka pastāv iespēja iegūt galaproduktu bez piemaisījumiem un sakārtot iegūtās nanodaļiņas ar elektriskā lauka palīdzību, lai iegūtu noteikto struktūru. Iegūtās metāliskās nanodaļiņas tiek raksturotas ar skenējošas elektronu mikroskopijas, transmisijas e…
A new method for forecasting energy output of a large-scale solar power plant based on long short-term memory networks a case study in Vietnam
2021
Abstract This paper proposes a new model for short-term forecasting power generation capacity of large-scale solar power plant (SPP) in Vietnam considering the fluctuations of weather factors when applying the Long Short-Term Memory networks (LSTM) algorithm. At first, a configuration of the model based on the LSTM algorithm is selected in accordance with the weather and operating conditions of SPP in Vietnam. Not only different structures of LSTM model but also other conventional forecasting methods for time series data are compared in terms of error accuracy of forecast on test data set to evaluate the effectiveness and select the most suitable LSTM configuration. The most suitable config…