Search results for "indicator"
showing 10 items of 997 documents
Control of solid-state fault current limiter for DG-integrated distribution systems
2017
Fault current limier (FCL) is a device that limits the system current under fault conditions without disconnecting the system and affecting the power system protection components such as circuit breakers. Many types of FCLs have been proposed to limit the magnitude of the fault current. Solid-state fault current limiters (SSFCLs) can limit the peak value of the fault current by applying several methods, such as controlling the system impedance or controlling the voltage that appears across the fault. In this paper, a new control scheme for the SSFCL circuit is presented. The control method is based on controlling the duty cycle of solid state switches to control the rms value of the system …
Risk Indicators and Road Accident Analysis for the Period 2012–2016
2017
Road accidents are a major societal issue for every country. The purpose of this paper is to assess the number of traffic and road accidents depending on a series of variables (collision mode, road configuration, conditions of occurrence, road category, type of vehicle involved, personal factors, and length of time of the driving license) in Romania from 2012–2016. The analysis of the road accident trend identifies the causes of accidents, road safety performance indicators, and risk indicators. Having these identified data, a framework is proposed for improving the road safety system and reducing accidents. The Romanian Police, the National Institute of Statistics (NIS) in Romania, and the…
Performance Management Systems – Proposing and Testing a Conceptual Model
2019
Abstract The utility of performance measurement and management system can be said to have been proven, but the problem faced by both the theoreticians and practitioners is to set the right performance indicators. Developed models are tools that managers can use to measure and manage performance, but they need to be tailored to the context. Also, the trend towards using non-financial performance indicators makes it very difficult for managers to design a performance measurement and management system because it involves the integration of qualitative and non-quantitative variables and a profound understanding of the internal and external environment of the company.
Keys to success in investment rounds by immigrant entrepreneurs in Silicon Valley
2019
[EN] This study presents an updated diagnosis of the SV ecosystem itself and offers an insight into the entrepreneurial mobility trends prospects and expectations of the growing number of start-ups launched by immigrant entrepreneurs arriving in SV. The purpose is to determine and rank the attributes most valued by investors when assessing projects and start-ups founded by immigrant entrepreneurs. The model of analysis composed by three hypotheses leads to a series of findings about the profile and expectations of the immigrant entrepreneurs, and reveals remarkable hints and key targets to be met by immigrant entrepreneurs in SV in order to successfully close investment rounds in a hypercom…
Uso de indicadores bibliométricos para el análisis de temas emergentes y su evolución: spin-offs como caso de estudio
2018
[ES] Las spin-offs constituyen una de las áreas de investigación más atractivas, ya que están asociadas con fenómenos como el emprendimiento, la innovación y la transferencia del conocimiento. El presente estudio muestra que la selección y el uso de indicadores bibliométricos permite identificar y caracterizar el desarrollo y la difusión de temas de investigación emergentes como el analizado. Los principales aspectos observados en relación con el desarrollo de la investigación sobre las spin-offs son que se produce un auge en el número de publicaciones después de un largo período de latencia y la marcada naturaleza multidisciplinar del área. El presente enfoque ha analizado la evolución de …
Medium-term dynamics of element concentrations in a sparid fish and its isopod parasite after the Prestige oil-spill: Shifting baselines?
2019
Historically, the European Atlantic is probably the most important oil-spill hotspot worldwide. One of the most recent accidents occurred in 2002 when the oil-tanker Prestige sank over the Galician Bank causing two major oil-spills followed by several small leaks until March 2003. This resulted in contamination of virtually all types of marine habitat. Considering that parasites have proved to be good effect and accumulation bioindicators, the present study addresses the medium-term changes in trace element content after the Prestige oil-spill in a model host-parasite system, the bogue, Boops boops (Sparidae) and the isopod Ceratothoa oestroides. To our knowledge, this study is the first to…
Occurrence of polybrominated diphenyl ethers, perfluorinated compounds, and nonsteroidal anti-inflammatory drugs in freshwater mussels from Latvia.
2018
Abstract The occurrence of polybrominated diphenyl ethers (PBDE), perfluorinated compounds (PFC), and nonsteroidal anti-inflammatory drugs (NSAID) in Latvian freshwater ecosystems was evaluated by using filter-feeding mussels as bioindicators. Twenty four samples of mussels were collected from freshwater bodies throughout the territory of Latvia during the summer of 2017. PBDE contamination was ubiquitous, reaching the highest total concentration of 193.2 pg g−1 w.w. BDE-209 was the most abundant compound, followed by penta-BDE components BDE-49, -100, −99, −153, −154, and −47 in decreasing order. The levels of PFCs in Latvian mussels were generally lower than those reported from other regi…
The use of blue tit eggs as a biomonitoring tool for organohalogenated pollutants in the European environment
2010
In the present study, large scale geographical variation in the occurrence of organohalogenated pollutants (OHPs) was investigated throughout Europe using eggs of a terrestrial resident passerine species, the blue tit (Cyanistes caeruleus). Blue tit eggs from 10 sampling locations, involving suburban, rural and remote areas, in 7 European countries were collected and analysed. Sum polychlorinated biphenyl (PCB) levels ranged from 150 ng/g lipid weight (lw) to 2003 ng/g lw. Sum polybrominated diphenyl ethers (PBDEs) ranged from 3.95 ng/g lw to 114 ng/g lw. As expected, PCB and PBDE concentrations were significantly higher in the sampled suburban locations compared to the rural and remote loc…
Characterization of the Etna volcanic emissions through an active biomonitoring technique (moss-bags): Part 1 – Major and trace element composition
2013
Active biomonitoring using moss-bags was applied to an active volcanic environment for the first time. Bioaccumulation originating from atmospheric deposition was evaluated by exposing mixtures of washed and air-dried mosses (Sphagnum species) at 24 sites on Mt. Etna volcano (Italy). Concentrations of major and a large suite of trace elements were analysed by inductively coupled mass and optical spectrometry (ICP-MS and ICP-OES) after total acid digestion. Of the 49 elements analysed those which closely reflect summit volcanic emissions were S, Tl, Bi, Se, Cd, As, Cu, B, Na, Fe, Al. Enrichment factors and cluster analysis allowed clear distinction between volcanogenic, geogenic and anthropo…
Photo-induced fluorescence of magnesium derivatives of tetracycline antibiotics in wastewater samples
2009
Abstract An analytical strategy, for the determination of tetracyclines (TCs), based on a HPLC system coupled with a photo-reactor followed by post-column derivatization was developed. Higher fluorescence emission after coupling the resulting photo-fragments with magnesium ions was observed for the determination of minocycline (MC), epitetracycline (ETC), tetracycline (TC) and doxycycline (DC). The manifold included a HPLC system with a photo-reactor (PTFE tubing helically coiled around a low-pressure mercury lamp), a mixing T-piece and a fluorescence detector. The derivatization reagent was delivered at 0.5 mL min −1 by a pump. After HPLC separation using a gradient system with a mobile ph…