Search results for "ample"
showing 10 items of 2398 documents
Business strategy in new high‐tech ventures: an empirical analysis
1999
The aim of this study is to determine the existence of specific and unique features characterising markets, activities and customers in at least two of the most representative high technology sectors nowadays, the microelectronics/software industry and the biotechnology/biomedical industry. Cross‐Tabs statistical method has been used to analyze the data collected from the sample made up by 18 high‐tech American firms. One of the major findings of this study is that the business strategy will hold better prospects in those high‐tech firms benefiting from a higher technological excellence, having spent longer time in developing and launching their products, being able to keep longer the novel…
The effect of protocol for disinfection of extracted teeth recommended by center for disease control (CDC) on microhardness of enamel and dentin
2015
Background: According to the guideline of the United States center for disease control (CDC), the extracted teeth should be sterilized by autoclaving or storage in 10% formalin before using for educational or research purposes. The objective of this study was to evaluate the effect of this protocol on microhardness of dentin and enamel. Material and Methods: Thirty extracted single-root teeth were used in this study. The crowns were resected, and the roots were longitudinally sectioned into two halves. The Vickers microhardness (VHN) of specimens was measured on polished canal dentin and buccal enamel surfaces. The crowns were randomly divided into three groups (n=10). Group 1 and 2 were st…
The effects of armed conflict on schooling in Sub-Saharan Africa
2012
In the past decades, most of the countries in sub-Saharan Africa have been affected by armed conflicts. By means of a time-series cross-sectional (TSCS) database, we attempt to measure the impact of war on a sample of 43 countries in Africa from 1950 to 2010. These conflicts, and especially civil wars, are shown to have a strong negative effect on the educational performances of the countries studied. The rate of children not attending school, as well as secondary school enrollment rates, seems particularly sensitive to periods of conflict. It also appears that government expenditures in social sectors including education are a positive factor in increasing school enrollment. In contrast, m…
Conceptual Understanding of Newtonian Mechanics Through Cluster Analysis of FCI Student Answers
2018
The Force Concept Inventory is a multiple-choice test and is one of the most popular and most analyzed concept inventories. It is used to investigate student understanding of Newtonian mechanics. A structured approach to data analysis can transform it in a “diagnostic” instrument that can validate inferences about student thinking. In this paper, we show how cluster analysis methods can be used to investigate patterns of student conceptual understanding and supply useful details about the relationships among student concepts and misconceptions. The answers given to the FCI questionnaire by a sample of freshman engineering have been analyzed. The analysis takes into account the decomposition…
H∞ fuzzy control of DC-DC converters with input constraint
2012
Published version of an article in the journal: Mathematical Problems in Engineering. Also available from the publisher at: http://dx.doi.org/10.1155/2012/973082 Open access This paper proposes a method for designing H∞ fuzzy control of DC-DC converters under actuator saturation. Because linear control design methods do not take into account the nonlinearity of the system, a T-S fuzzy model and a controller design approach is used. The designed control not only handles the external disturbance but also the saturation of duty cycle. The input constraint is first transformed into a symmetric saturation which is represented by a polytopic model. Stabilization conditions for the H∞ state feedba…
Modeling traffic safety at urban four leg-signalized intersections
2013
According to the state-of-the-art of the methodologies, the development of safety performance functions (SPFs) for road sections and intersections requires the employment of statistical models to predict expected crash frequencies on the basis of traffic volumes and site characteristics to be surveyed and used as input to models. Nevertheless, literature reports several studies on issues deriving from data features or methodological approaches that may invalidate the efficiency of the models and the accuracy of the estimates. Drawing inspiration from the above mentioned considerations, the objective of this study is to develop safety performance functions for a sample of urban four leg-sign…
A Rough-Terrain Casting Robot for the ESA Lunar Robotics Challenge
2009
This paper describes the design and implementation of DAVID, a lunar vehicle developed for the European Space Agency (ESA) Lunar Robotics Challenge, presenting severe terrain negotiation and sample acquisition challenges. We discuss in some detail two of the main innovative aspects of our entry to the challenge, i.e. the locomotion system and the sample acquisition system. Motivated by the challenge specifications, a range of different locomotion systems were considered, among which we chose a simple, rugged and effective wheeled system. We provide an account of the choice of five different types of wheels, which were designed, analyzed and experimentally tested in conditions similar to the…
Misura delle performance finanziarie e patrimoniali delle aziende agricole: proposta operativa per un nuovo modello di rating per le aziende agricole
2012
La profonda evoluzione dei sistemi agricoli negli ultimi anni hanno accresciuto l'attenzione di tutti gli attori istituzionali ed economici rispetto alla problematica dell'accesso al credito per le imprese. Nel passato molto spesso il credito in agricoltura ha usufruito di regimi "speciali"; con l'implementazione delle regole di Basilea 2 (più di recente Basilea 3), le condizioni per l'accesso al credito si sono notevolmente irrigidite. Nell'ambito del settore agricolo, la pressoché assenza di bilanci certificati rende particolarmente difficoltosa questa valutazione. Nel presente lavoro, dopo aver analizzato la letteratura in materia di valutazione del merito creditizio delle aziende agrico…
Testing the usability of the Rapid Impact Assessment Matrix (RIAM) method for comparison of EIA and SEA results
2008
Abstract This study examines how the results of Environmental Impact Assessment (EIA) and Strategic Environmental Assessment (SEA) could be compared using the Rapid Impact Assessment Matrix (RIAM) method. There are many tools and techniques that have been developed for use in impact assessment processes, including scoping, checklists, matrices, qualitative and quantitative models, literature reviews, and decision-support systems. While impact assessment processes have become more technically complicated, it is recognized that approaches including simpler applications of available tools and techniques are also appropriate. The Rapid Impact Assessment Matrix (RIAM) is a tool for organizing, a…
Efficiency assessment of wastewater treatment plants: A data envelopment analysis approach integrating technical, economic, and environmental issues
2015
The assessment of the efficiency of wastewater treatment plants (WWTPs) is essential to compare their performance and consequently to identify the best operational practices that can contribute to the reduction of operational costs. Previous studies have evaluated the efficiency of WWTPs using conventional data envelopment analysis (DEA) models. Most of these studies have considered the operational costs of the WWTPs as inputs, while the pollutants removed from wastewater are treated as outputs. However, they have ignored the fact that each pollutant removed by a WWTP involves a different environmental impact. To overcome this limitation, this paper evaluates for the first time the efficien…