Search results for "Opera"

Absolutely summing operators on C[0,1] as a tree space and the bounded approximation property

AbstractLet X be a Banach space. For describing the space P(C[0,1],X) of absolutely summing operators from C[0,1] to X in terms of the space X itself, we construct a tree space ℓ1tree(X) on X. It consists of special trees in X which we call two-trunk trees. We prove that P(C[0,1],X) is isometrically isomorphic to ℓ1tree(X). As an application, we characterize the bounded approximation property (BAP) and the weak BAP in terms of X∗-valued sequence spaces.

Dasymetric distribution of votes in a dense city

2017

[EN] A large proportion of electoral analyses using geography are performed on a small area basis, such as polling units. Unfortunately, polling units are frequently redrawn, provoking breaks in their data series. Previous electoral results play a key role in many analyses. They are used by political party workers and journalists to present quick assessments of outcomes, by political scientists and electoral geographers to perform detailed scrutinizes and by pollsters and forecasters to anticipate electoral results. In this paper, we study to what extent more complex geographical approaches (based on a proper location of electors on the territory using dasymetric techniques) are of value in…

A Model for Developing an Academic Activity Index for Higher Education Instructors Based on Composite Indicators

2020

The assessment of the teacher performance is a subject of criticism due to the lack of a well-establish methodology. This study develops an overall score to measure the dimensions that encompass the academic activities. To that end, a Benefit-of-the-doubt model is proposed. The advantage of this technique is the flexibility in the weights, so that the model selects for each teacher the most favourable set of weights. Furthermore, the paper proposes the barycentric coordinate system as a method to classify the teachers in clusters depending on their contribution to the dimensions. A specific pie chart has been proposed as an efficient way to report the contribution of the teachers to the di…

The pricing capability lifecycle of digital innovations

2021

The pricing capability provides a basis for firms’ competitive advantage. However, to date, the literature has not investigated how this capability forms, develops, and matures. In this study, we define the pricing capability as a dynamic capability consisting of three operational building blocks (tools and data, human and relational resources, and processes, routines, and mechanisms) as well as two dynamic capability building blocks (alertness and responsiveness, and value-based strategic thinking). Furthermore, we propose the pricing capability lifecycle of digital innovations that incorporates insights of the dynamic capabilities view (DCV). Based on a longitudinal multi-case study of fi…

Life cycle assessment of storage systems: the case study of a sodium/nickel chloride battery

2014

This study assesses the energy and environmental impacts of sodium/nickel chloride batteries, one of the emerging battery technologies for energy storage and smart grids. The analysis was conducted using the Life Cycle Assessment methodology according to the standards of the ISO 14040 series. The study system was one sodium/nickel cell battery providing electric storage for a photovoltaic system, and the manufacturing, operation, and end-of-life steps were analysed. The results indicated that the operation step has the greatest energy impact (55-70% of the total), with the manufacturing step, particularly cell manufacturing, contributing the greatest environmental impact (>60% of the total)…

Stationary battery systems in the main world markets: Part 2: Main trends and prospects

2017

Stationary battery systems are gaining a lot of interest in recent years, mainly because of their ability to balance generation and demand of electricity over time. The intermittent nature of renewable generation connected to the power grid is causing major stability and reliability issues in the power system, that can be solved also using stationary storage systems, able to provide the ancillary services necessary to the proper operation of the power network. Despite the considerable advantages offered by these technologies, the electrochemical storage industry is still in the nascent state and it is important to identify the main trends and prospects in relation to future technical develo…

Determining noise and vibration exposure in conifer cross-cutting operations by using Li-Ion batteries and electric chainsaws

2018

In many activities, chainsaw users are exposed to the risk of injuries and several other hazard factors that may cause health problems. In fact, environmental and working conditions when using chainsaws result in workers&rsquo

Practical Considerations in the Implementation of Collaborative Beamforming on Wireless Sensor Networks

2017

Wireless Sensor Networks (WSNs) are composed of spatially distributed autonomous sensor devices, named motes. These motes have their own power supply, processing unit, sensors and wireless communications However with many constraints, such as limited energy, bandwidth and computational capabilities. In these networks, at least one mote called a sink, acts as a gateway to connect with other networks. These sensor networks run monitoring applications and then the data gathered by these motes needs to be retrieved by the sink. When this sink is located in the far field, there have been many proposals in the literature based on Collaborative Beamforming (CB), also known as Distributed or Cooper…

Color constancy in goldfish: the limits

2000

Color constancy was investigated in behavioral training experiments on colors ranging from blue to yellow, located in the color space close to Planck's locus representing the main changes in natural skylight. Two individual goldfish were trained to peck at a test field of medium hue out of a series of 13-15 yellowish and bluish test fields presented simultaneously on a black background. During training the tank in which the fish were swimming freely was illuminated with white light. Correct choices were rewarded with food. During the tests differently saturated yellow or blue illumination was used. The degree of color constancy was inferred from the choice behavior under these illuminations…

The Impact of the New Rural Cooperative Medical Scheme on Township Hospitals' Utilization and Income Structure in Weifang Prefecture, China

2017

The New Rural Cooperative Medical Scheme was gradually introduced from 2003 in China. This paper is based on a representative survey of 24 randomly selected township hospitals in Weifang prefecture over the period 2000-2008. Using a generalized form of differences-in-differences model, it aims to assess the effect of the reform on the utilization and income structure of the township hospitals. The estimations provide three main results linked to the effects of the New Rural Cooperative Medical Scheme on the behavior of the key stakeholders (households, health care providers and Health Bureau). Firstly, the reform had positive impacts on the utilization of township hospitals, particularly on…