1,667 research outputs found
Performance Measurement Systems, Competitive Priorities, and Advanced Manufacturing Technologies: Some Evidence from the Aeronautical Sector
Purpose – When acquiring advanced manufacturing technologies (AMT), the greatest caution should be taken regarding the performance measurement system to be used: the decision regarding new investments should not be conditioned by the excessive use of financial indicators to the detriment of the strategic objectives that motivated the investments. It is intended to analyze the aeronautical sector, for which the purchase of AMT is qualifying criteria, with two intentions: first, to identify the performance measurement systems that are used, and second, to test their correspondence with the objectives that motivated the investments. Design/methodology/approach – A survey of the 20 plants in the population was conducted via a postal questionnaire plus a structured interview. The unit of analysis has been maintained through the triangulation of data sources. Findings – The findings suggest that both financial and non-financial indicators are used, with the latter gaining predominance over the former on some occasions, even though there is no clear correspondence between strategy and the measurement of performance. In the light of the findings, the question of what inspires a company’s performance measurement system is still open, especially in those cases where there is no explicit strategy. With regard to practical implications, what seems to be indispensable is an improvement in the determination of the critical variables that should be used to measure performance. Research limitations/implications – Being valuable for academics and practitioners, this contribution relies, rather, on the possibility of a logical extrapolation to circumstances where the findings might apply, and researchers can judge whether the particular findings would be valid. Originality/value – Provides new evidence on the adaptation of the make-up and combination of the type of performance measures currently used by plants in the aeronautical industry, one of the sectors in which technological innovation is of the utmost importance.Publicad
Adopting and Implementing AMT: New Data on Key Factors from the Aeronautical Industry.
The objective of this paper is to take a greater in-depth look at which factors might be considered to be key to the performance of investments made in advanced manufacturing technologies (AMT), given their supposed positive effects, and on the influence that the time these factors are taken into account during the adoption and implementation process can have on that relationship. It provides a specially devised empirical analysis in the aeronautical sector in the south of Spain. A survey of the 20 plants in the population was conducted via a postal questionnaire between July 1999 and April 2001, with a structured interview being held at a later date. The testing of hypotheses was performed by applying the t-test to independent samples. The results show that the only factor that has a clear and positive effect on performance is the training of personnel. It can also be seen that a lack of strategic planning contributes to dampening the effects of investments. These results may be of some help to management staff and public administrators in charge of promoting the process of technological innovation, by indicating actions that need to be taken in order to successfully adopt and implement AMT.
Near Field Communication with Amazon Web Services
Internet of Things (IoT) has become the trending topic of collaborative applications by connecting many kinds of devices together via internet, and thus, allowing flexible solutions for remote control devices. These applications can work together with communication protocols like Near Filed Communication (NFC) to complement secure intended approaches. One concern of embedded IoT devices development is the customized developments which limit portability. The present work aims to show a secure NFC embedded IoT device using the LPC54018_IoT development board working together with AWS, specifically using AWS services Lambda and IoT Core. By working with these elements there is the advantage of using an existing framework for connection, data exchange and cloud code execution. The outcome of the project displays a solution that can authenticate NFC tag devices dynamically using data generated from the cloud service and then, synchronize with the embedded development board. Future improvements can be considered for this project in regards of increased cloud server security and device mobility by migrating to a cellular network based connection
EMISSION AND ATMOSPHERIC IMPACT OF A CUBAN REFINERY
In the processes of an oil refinery, considerable emissions of atmospheric pollutants are
generated that produces hazard to mans health and the environment. In this study, the
obtained results of the characterization of the gaseous emissions by chimneys of the furnaces
and boilers of the refinery are presented. The sampling and analysis of SO2, NOX, CO,
total suspended particles, and flow measurements were carried out. The aromatic
hydrocarbons were determined by UV Spectroscopy. The model of dispersion of pollutants
emitted by chimneys was executed using the software for the calculation of the gas
concentration from continuous industrial sources following the methodology approved in
the Cuban standards, according to the Berliand Model. We conclude that the combustion
processes of the Refinery reflect a fault, given the particles emissions. The emissions of
the furnaces and boilers exert negative impact or pressure on the atmospheric environment
in the area
Reconstructing the origins and the biogeography of species’ genomes in the highly reticulate allopolyploid-rich model grass genus Brachypodium using minimum evolution, coalescence and maximum likelihood approaches
The identification of homeologous genomes and the biogeographical analyses of highly reticulate allopolyploid-rich groups face the challenge of incorrectly inferring the genomic origins and the biogeographical patterns of the polyploids from unreliable strictly bifurcating trees. Here we reconstruct a plausible evolutionary scenario of the diverging and merging genomes inherited by the diploid and allopolyploid species and cytotypes of the model grass genus Brachypodium. We have identified the ancestral Brachypodium genomes and inferred the paleogeographical ranges for potential hybridization events that originated its allopolyploid taxa. We also constructed a comprehensive phylogeny of Brachypodium from five nuclear and plastid genes using Species Tree Minimum Evolution allele grafting and Species Network analysis. The divergence ages of the lineages were estimated from a consensus maximum clade credibility tree using fossil calibrations, whereas ages of origin of the diploid and allopolyploid species were inferred from coalescence Bayesian methods. The biogeographical events of the genomes were reconstructed using a stratified Dispersal-Extinction-Colonization model with three temporal windows. Our combined Minimum Evolution-coalescence-Bayesian approach allowed us to infer the origins and the identities of the homeologous genomes of the Brachypodium allopolyploids, matching the expected ploidy levels of the hybrids. To date, the current extant progenitor genomes (species) are only known for B. hybridum. Putative ancestral homeologous genome have been inherited by B. mexicanum, ancestral and recent genomes by B. boissieri, and only recently evolved genomes by B. retusum and the core perennial clade allopolyploids (B. phoenicoides, B. pinnatum 4x, B. rupestre 4x). We dissected the complex spatio-temporal evolution of ancestral and recent genomes and have detected successive splitting, dispersal and merging events for dysploid homeologous genomes in diverse geographical scenarios that have led to the current extant taxa. Our data support Mid-Miocene splits of the Holarctic ancestral genomes that preceded the Late Miocene origins of Brachypodium ancestors of the modern diploid species. Successive divergences of the annual B. stacei and B. distachyon diploid genomes were implied to have occurred in the Mediterranean region during the Late Miocene-Pliocene. By contrast, a profusion of splits, range expansions and different genome mergings were inferred for the perennial diploid genomes in the Mediterranean and Eurasian regions, with sporadic colonizations and further mergings in other continents during the Quaternary. A reliable biogeographical scenario was obtained for the Brachypodium genomes and allopolyploids where homeologous genomes split from their respective diploid counterpart lineages in the same ancestral areas, showing similar or distinct dispersals. By contrast, the allopolyploid taxa remained in the same ancestral ranges after hybridization and genome doubling events. Our approach should have utility in deciphering the genomic composition and the historical biogeography of other allopolyploid-rich organismal groups, which are predominant in eukaryotes
Microstructure Effects on the Machinability of AM-Produced Superalloys
This paper discusses the microstructure effects on the machinability of Inconel 718 by conducting machining tests on an additively manufactured (AM) workpiece with a strongly textured grain structure and a wrought workpiece incorporating a finer and more equiaxed grain structure. The AM workpiece was produced as a thin tube using Laser Melting Powder Bed Fusion and optimal processing conditions for this alloy. A lathe was used to conduct instrumented orthogonal machining tests on the two workpiece materials under dry cut and coolant conditions using a semisynthetic emulsion coolant. The process parameters studied were feed from 0.05 to 0.15 mm/rev and cutting speed from 60 to 120 m/min with a cut time of 2 sec duration for each process condition. Measures for each process condition included cutting forces in the feed and main cut direction, and images of chip forms were obtained. The grain structures of the workpiece materials were characterized using Electron Back Scattered Diffraction (EBSD). New findings suggest that grain structures can significantly affect the machinability of the superalloy at a higher feed for all cutting speeds studied, and insights into the cause are discussed. Other important findings comment on the effectiveness of the coolant as a lubricant for reducing friction in machining
Estimation of the Primary Net Production above Ground through Remote Sensing in a Pastoral System of the Colombian Altillanura.
The primary net production above ground (ANPP) represents the main forage resource that supports the bovine production systems and its valuation is essential to help in the decision making on the management of the pastures. The ANPP has been estimated by periodic biomass courtesy, but with the use of the remote sensor integrated into the efficiency model formulated by Monteih (1972), it has been possible to estimate this biophysical parameter more efficiently at different scales and at low cost. The objective of this study was to estimate the PPNA based on a model of efficiency in the use of light for pastoral coverage in the Colombian Altillanura. The work is in the Carimagua Research Center of the Colombian Agricultural Research Corporation –AGROSAVIA– located in the municipality of Puerto Gaitán - Meta, Colombia. The pasture was monitored through forage supply gaps, in 14 paddocks with an approximate area of 2.6 ha each, established with Urochloa humidicola CIAT 6133 c.v Llanero under grazing of cattle with rest periods of 28 to 30 days. The spectral information was obtained from the on-board Sentinel 2 sensor and the global radiation data was obtained from a field weather station. A PPNA observed in the field and estimated by the efficiency model of 603.79 ±189kgDM/ha ± 188 and de 589.22 ±104 kgDM/ha was found, with a coefficient of determination R2 (0.79) and a significant correlation p \u3c 0.01 of 0.89. This methodology would quantify the supply of fodder on a larger scale under the same type of pastures
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