Search results for "efficiency"
showing 10 items of 1430 documents
The optimisation of sampling design
2013
Elektroniskā versija nesatur pielikumus
Challenges to the development of energy performance measurement : a systems thinking approach
2016
Growing global energy consumption and its consequent hindrance to sus-tainable development poses one of the greatest challenges of today. Impro-vement of the end-use energy efficiency is commonly regarded as one of the most basic and significant countermeasures for curbing the rising energy needs. However, it seems that the progress of end-use energy management is currently hindered due to the complexities involved in the measurement and management of energy efficiency. In essence, the lack of appropriate energy performance metrics constitute a gap between the current organizational needs and scientific literature. Furthermore, the current scientific debate has questioned whether ener-gy ef…
Dependency on un-captured GDP as a source of resilience beyond economic value in countries with advanced ICT infrastructure: Similarities and dispari…
2015
Abstract The majority of countries with advanced information and communication technology (ICT) infrastructure have been experiencing extended stagnation due to an “embedded” trap in ICT advancement. However, certain countries have been able to sustain a high level of ICT- driven global competitiveness. This suggests that in these contexts there is resilience beyond economic value. Finland and Singapore can be considered countries of resilience with respect to ICT-driven global competitiveness because of their continued GDP growth despite the recession. While both countries share significant similarities including institutional strength in ICT, they demonstrate noteworthy disparities in the…
Comparing the cost-efficiency of CoAP and HTTP in Web of Things applications
2014
Abstract Constrained Application Protocol (CoAP) has been introduced as a simpler alternative to the Hypertext Transfer Protocol (HTTP) for connecting constrained smart objects to the Web. The adoption of the protocol depends on its relative advantage, and the cost–benefit associated with the use of the protocol is a significant factor affecting a protocol adoption decision. This paper aims at deepening the understanding of the cost–benefits of CoAP and identifies the application scenarios where its use is likely to be economically justifiable. The paper analyzes the costs of using CoAP and HTTP in the Web of Things (WoT) applications, by identifying the components of the total cost of owne…
Effect of Ion Escape Velocity and Conversion Surface Material on H- Production
2011
According to generally accepted models surface production of negative ions depends on ion escape velocity and work function of the surface. We have conducted an experimental study addressing the role of the ion escape velocity on H− production. A converter‐type ion source at Los Alamos Neutron Science Center was employed for the experiment. The ion escape velocity was affected by varying the bias voltage of the converter electrode. It was observed that due to enhanced stripping of H− no direct gain of extracted beam current can be achieved by increasing the converter voltage. The conversion efficiency of H− was observed to vary with converter voltage and follow the existing theories in qual…
Does innovativeness reduce startup survival rates?
2015
There are two competing hypotheses explaining how innovativeness influences the survival of startups: On the one hand, innovativeness is argued to foster survival-enhancing attributes (e.g., market power and cost efficiency) and capabilities (e.g., absorptive capacity). On the other hand, an innovative startup faces (and bears the associated risks of) liabilities of newness and smallness that exceed those of its non-innovative counterparts. The available empirical literature addressing this theoretical tension mostly supports the former hypothesis; we suggest that this finding is, in part, driven by the common practice of employing an ex post measure that already embodies a degree of succes…
High-Performance Lead-Acid Batteries Enabled by Pb and PbO2 Nanostructured Electrodes: Effect of Operating Temperature
2021
Lead-acid batteries are now widely used for energy storage, as result of an established and reliable technology. In the last decade, several studies have been carried out to improve the performance of this type of batteries, with the main objective to replace the conventional plates with innovative electrodes with improved stability, increased capacity and a larger active surface. Such studies ultimately aim to improve the kinetics of electrochemical conversion reactions at the electrode-solution interface and to guarantee a good electrical continuity during the repeated charge/discharge cycles. To achieve these objectives, our contribution focuses on the employment of nanostructured electr…
The thermal performances of historic masonry: In-situ measurements of thermal conductance on calcarenite stone walls in Palermo
2018
Abstract Rich literature explores materials and construction techniques of historic buildings, but limited information is available about the thermal and hygrometric features of their envelope. Nevertheless, accurate hygrothermal data are essential for identifying effective energy upgrade measures, which must be compatible with the conservation of the architectural heritage. In order to fill this gap, it is necessary to refer to local contexts, where the variety of historic buildings is limited and their material and construction features are comparable. This paper focuses on historic masonry walls and discusses the results of twenty in-situ measurements of thermal conductance, performed al…
The Recurrent Characteristics of Historic Buildings as a Support to Improve their Energy Performances: The Case Study of Palermo
2017
Abstract The analysis of the recurrent characteristics of the local historic architecture is useful to develop large-scale energy analyses, regulations and financial strategies, but also to support technical guidelines for an energy improvement balanced with conservation. For this purpose, a multi-scale methodology ranging from envelope components to the urban dimension is necessary. In the research here exposed, this approach is investigated by focusing on the historic architecture of Palermo. For this heritage, the collection of thermal and hygrometric data for envelope components is combined with the examination of representative constructions, based on building stock categorization. Int…
Calibration of a small anode germanium well detector
2017
SAGe kolokiteen kalibroinnit suoritettiin kolmelle näytegeometrialle. Kaksi geometrioista oli sylinterin muotoisia purkkeja, jotka mitattiin ilmaisimen päällä ja yksi koeputki, joka mitattiin kolon sisällä. Piikkitehokkuuskalibrointi tehtiin NPL:sta tilattujen sertifioitujen näytteiden avulla. Yksinuklidinäytteitä valmistettiin radioaktiivisista liuoksista totaalitehokkuuskalibrointia varten. Totaalitehokkuuskäyrä saatiin simuloimalla totaalitehokkuudet MCNP:llä ja sovittamalla malli vastaamaan kokeellisia tuloksia. Kalibraatiot tehtiin energiavälille 30 keV–1.9 MeV. Kalibroinnit olivat tarpeeksi luotettavia, että ilmaisinta voidaan käyttää akkreditoiduissa gammaspektrometrisissä mittauksis…