938 resultados para Drawing, Italian


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Hop (Humulus lupulus L.) is a dioecius perennial plant. The cultivation is specific for female plants, used mainly for brewing and pharmacology. Female inflorescence, known as cone or strobili, contains bitter acids, essential oil and polyphenols. Commercial hop cultivation provides better results in regions between 45 and 55 degrees north or south in latitude, an area that also includes the northern part of Italy, where hop is endemic. Despite several studies have been conducted on the characterization of wild hops biodiversity in the U.S.A. and Europe, a lack in literature concerning the description of Italian wild hops genetic variability is still present. The increasing request of hop varieties improved in important traits, like diseases, resistance and valuable aroma profile, is bringing the hop industry. Moreover, Italian agricultural sector needs new impulse to be competitive in the market. In this view, Italian wild hop biodiversity is a resource, useful for the obtaining of Italian hop varieties, characterized by peculiar aromatic traits and more adaptable to Mediterranean climate, making their cultivation more sustainable. Based on this consideration, the present Ph.D. thesis deals with the evaluation of the Italian hop biodiversity, through the characterization of the wild samples under different point of view. The project started with the recovery of wild hop samples in different areas of north of Italy to consitue a collection field, where 11 commercial cultivars of US and European origin were grown, to have a complete vision of the hop panorama. Ph.D. project followed different research lines, the results of each one contributed to completly characterize the northern Italian hop wild biodiversity: • the morphological description showed a high phenological variability (Study 1); • the genetic characterization confirmed the rich biodiversity of the Italian population and showed a significant genetic distance between Italian genotypes and the commercial cultivars, taken in consideration (Study 2); • the need of an early sex discrimination method leads to an improvement of a genetic marker, developing a more efficient marker (Study 3); • a complete morphologic, genetic and chemical analysis of plants gave results to select the most promising genotypes (Study 4); • the comparison between the performance of wild hops and commercial cultivars in the same collection field indicated that some wild genotypes had a higher environment adaptability (Study 5); • the evaluation of the terroir, obtained comparing commercial cultivars in the collection field and the same genotypes purchased in the market, showed the influence of the northern Italian environment on the aromatic profile (Study 5); • a new analytical method for the revelation of bioactive metabolites and a simple extraction procedure were developed (Study 6). In conclusion, the Ph.D. thesis, contains the first characterization of Italian wild hop, made under field condition. The present study: i) permits to obtain a complete and significative description of the genotypes; ii) allows the identification of the most promising wild Italian genotypes; iii) allows the identification of commercial cultivars more adaptable the northern Italian climate.

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A number of investigators have studied the application of oscillatory energy to a metal undergoing plastic deformation. Their results have shown that oscillatory stresses reduce both the stress required to initiate plastic deformation and the friction forces between the tool and workpiece. The first two sections in this thesis discuss historically and technically the devolopment of the use of oscillatory energy techniques to aid metal forming with particular reference to wire drawing. The remainder of the thesis discusses the research undertaken to study the effect of applying longitudinal oscillations to wire drawing. Oscillations were supplied from an electric hydraulic vibrator at frequencies in the range 25 to 500 c/s., and drawing tests were performed at drawing speeds up to 50 ft/m. on a 2000 lbf. bull-block. Equipment was designed to measure the drawing force, drawing torque, amplitude of die and drum oscillation and drawing speed. Reasons are given for selecting mild steel, pure and hard aluminium, stainless steel and hard copper as the materials to be drawn, and the experimental procedure and calibration of measuring equipment arc described. Results show that when oscillatory stresses are applied at frequencies within the range investigated : (a) There is no reduction in the maximum drawing load. (b) Using sodium stearate lubricant there is a negligible reduction in the coefficient of friction between the die and wire. (c) Pure aluminium does not absorb sufficient oscillatory energy to ease the movement of dislocations. (d) Hard aluminium is not softened by oscillatory energy accelerating the diffusion process. (e) Hard copper is not cyclically softened. A vibration analysis of the bull-block and wire showed that oscillatory drawiing in this frequency range, is a mechanical process of straining; and unstraining the drawn wire, and is dependent upon the stiffness of the material being drawn and the drawing machine. Directions which further work should take are suggested.

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With the rise of 'New Public Management' (NPM), government policy has encouraged public-sector organizations to downsize and outsource their services. There is, however, local variation in the use of outsourcing - this is 'managing from the inside out'. This paper draws on the notion of receptivity for organizational change to explain variation in strategy implementation. Four receptivity factors are identified which seem to explain the success of two contrasting English local government outsourcing strategies: ideological vision, leading change, institutional politics and implementation capacity. The organization level of change is interconnected with two other levels of change (the public service and environment levels) to illustrate the dynamic nature of change.

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In this paper, we analyse the nature of the relationship between market power and technical efficiency for producers' cooperatives. More specifically we test two hypotheses: first, we evaluate the extent to which increasing market pressure may help producers' cooperatives to improve technical efficiency to guarantee positive profits; second, we test whether higher technical efficiency induces producers' cooperatives to have a larger market share. These hypotheses are tested on a sample of Italian conventional and cooperative firms for the Wine Production and Processing sector, using both frontier analysis and dynamic panel techniques. The results support the hypothesis that increasing market pressure can affect positively the cooperativeś efficiency, while gains in technical efficiency do not seem to have any impact on the cooperatives' market share. © 2008 Springer Science+Business Media, LLC.

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The purpose of this paper is to analyse the relationship between the corporate governance system and technical efficiency in Italian manufacturing. We use a non-parametric frontier technique (DEA) to derive technical efficiency measures for a sample of Italian firms taken from nine manufacturing industries. These measures are then related to the characteristics of the corporate governance system. Two of these characteristics turn out to have a positive impact on technical efficiency: the percentage of the company shares owned by the largest shareholder and the fact that a firm belongs to a pyramidal group. Interestingly, a trade-off emerges between these influences, in the sense that one is stronger in industries where the other is weaker. Copyright © 2007 John Wiley & Sons, Ltd.

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This paper analyses the relationship between industrial total factor productivity and public capital across the 20 Italian administrative regions. It adds upon the existing literature in a number of ways: it analyses a longer period (1970-98); it allows for the role of human capital accumulation; it tests for the existence of a long-run relationship between total factor productivity and public capital (through previously suggested panel techniques) and for weak exogeneity of public capital; and it assesses the significance of public capital within a non-parametric set-up based on the Free Disposal Hull. The results confirm that public capital has a significant impact on the evolution of total factor productivity, particularly in the Southern regions. This impact is mainly ascribed to the core infrastructures (road and airports, harbours, railroads, water and electricity, telecommunications). Also, core infrastructures are weakly exogenous. © 2005 Regional Studies Association.

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This paper tries to identify under which conditions increasing market competition may help cooperatives to improve technical efficiency to guarantee positive profits. This hypothesis is first formalized in a partial equilibrium framework and then is tested on a sample of Italian conventional and cooperative firms, using frontier analysis. Technical efficiency indexes are computed by using the one-stage approach as suggested by Battese and Coelli (1995), where proxies for competition are introduced as determinants of efficiency, along with other exogenous factors accounting for the firms’ heterogeneity. However, the overall impact of increasing competition on efficiency is negative.