2,275 research outputs found
Total Factor Productivity Growth in Agriculture: A Malmquist Index Analysis of 93 Countries, 1980-2000
In this paper we examine levels and trends in agricultural output and productivity in 93 developed and developing countries that account for a major portion of the world population and agricultural output. We make use of data drawn from the Food and Agriculture Organization of the United Nations and our study covers the period 1980-2000. Due to the non-availability of reliable input price data, the study uses data envelopment analysis (DEA) to derive Malmquist productivity indexes. The study examines trends in agricultural productivity over the period. Issues of catch-up and convergence, or in some cases possible divergence, in productivity in agriculture are examined within a global framework. The paper also derives the shadow prices and value shares that are implicit in the DEA-based Malmquist productivity indices, and examines the plausibility of their levels and trends over the study period
Characterization of Large Volume 3.5 x 8 inches LaBr3:Ce Detectors
The properties of large volume cylindrical 3.5 x 8 inches (89 mm x 203 mm)
LaBr3:Ce scintillation detectors coupled to the Hamamatsu R10233-100SEL
photo-multiplier tube were investigated. These crystals are among the largest
ones ever produced and still need to be fully characterized to determine how
these detectors can be utilized and in which applications. We tested the
detectors using monochromatic gamma-ray sources and in-beam reactions producing
gamma rays up to 22.6 MeV; we acquired PMT signal pulses and calculated
detector energy resolution and response linearity as a function of gamma-ray
energy. Two different voltage dividers were coupled to the Hamamatsu
R10233-100SEL PMT: the Hamamatsu E1198-26, based on straightforward resistive
network design, and the LABRVD, specifically designed for our large volume
LaBr3:Ce scintillation detectors, which also includes active semiconductor
devices. Because of the extremely high light yield of LaBr3:Ce crystals we
observed that, depending on the choice of PMT, voltage divider and applied
voltage, some significant deviation from the ideally proportional response of
the detector and some pulse shape deformation appear. In addition, crystal
non-homogeneities and PMT gain drifts affect the (measured) energy resolution
especially in case of high-energy gamma rays. We also measured the time
resolution of detectors with different sizes (from 1x1 inches up to 3.5x8
inches), correlating the results with both the intrinsic properties of PMTs and
GEANT simulations of the scintillation light collection process. The detector
absolute full energy efficiency was measured and simulated up to gamma-rays of
30 Me
First prototype of a silicon tracker using an artificial retina for fast track finding
We report on the R\&D for a first prototype of a silicon tracker based on an
alternative approach for fast track finding. The working principle is inspired
from neurobiology, in particular by the processing of visual images by the
brain as it happens in nature. It is based on extensive parallelisation of data
distribution and pattern recognition. In this work we present the design of a
practical device that consists of a telescope based on single-sided silicon
detectors; we describe the data acquisition system and the implementation of
the track finding algorithms using available digital logic of commercial FPGA
devices. Tracking performance and trigger capabilities of the device are
discussed along with perspectives for future applications.Comment: 9 pages, 7 figures, Technology and Instrumentation in Particle
Physics 2014 (TIPP 2014), conference proceeding
Do PGI integrated farms perform better? The case of the beef farms in Spain
European rural development policy is gaining in importance through one of its key instruments, the Protected Geographical Indications (PGI) system, which is designed to improve quality standards. Previous research has shown that PGI-certified beef farms tend to be more extensively managed operations that are better adapted to mountainous areas. This paper describes a comparative study of two production systems, one with PGI certification and one without, focusing on a number of economic variables. The results show a positive association between PGI production and profitability. In efficiency terms, non-certified farms show better pure technical efficiency scores, while PGI-certified holdings score higher on scale efficiency
School performance in Australia: is there a role for quasi-markets?
Recent changes to the organisation of Australia's education system have raised the possibility of implementing wide-ranging market reforms. In this article we discuss the scope for introducing reforms similar to the United Kingdom's 'quasi-market' model. We discuss the role of school league tables in providing signals and incentives in a quasi-market. Specifically, we compare a range of unadjusted and model-based league tables of primary school performance in Queensland's public education system. These comparisons indicate that model-based tables which account for socio-economic status and student intake quality vary significantly from the unadjusted tables
Measuring the efficiency of Serbian insurance companies
The transition period, and the still ongoing economic crisis, amplify the volatility in the domestic insurance market and forces the management of insurance companies to continuously monitor changes in the market, i.e. to identify risks and opportunities, and therefore to undertake certain activities. The focus of the business of insurance companies is based on satisfying the needs of existing and potential clients. Respecting the current situation in the insurance market in anticipation of future events, the management of insurance companies must create and implement the optimal strategy in line with the companyâs capabilities. For this purpose it is necessary to measure the efficiency of the business, which is the subject of this paper where the Data Envelopment Analysis (DEA) method is applied to the case of insurance companies operating in Serbia
Characterization of Large Volume 3.5âł x 8âł LaBr3:Ce Detectors for the HECTOR+ array
A selection of the properties of large volume, cylindrical 3.5" x 8" LaBr 3 :Ce scintillation detectors coupled to a 3.5" PMT (model R10233-1000SEL from HAMAMATSU) and a special designed Voltage Divider (LABRVD) will be discussed. A number of 10 of such detectors constitute the HECTOR + array which, in fall 2012, measured at GSI coupled to the AGATA DEMOSTRATOR at the PRESPEC experimental setup. These crystals are among the largest ever produced and needed to be characterized. We have performed several tests and here we discuss, in particular, the energy resolution measured using monochromatic Îł âray sources and in-beam reactions producing Îł ârays up to 22.6 MeV. As already measured in two previous works a saturation in the energy resolution was observed in case of high energy gamma rays. Crystal non-homogeneities and PMT gain drifts can affect the resolution of measurements especially in case of high energy Îł ârays
Corporate real estate analysis: evaluating telecom branch efficiency in Greece
This paper proposes productivity analysis for evaluating the relative efficiency in corporate real estate usage across decision-making units. Using data from the Greek Telecommunications Organization (GTO), we measure the productivity of 127 braches using the number of employees and the total area covered per building as inputs and the number of telephony access lines as outputs. We apply three non-parametric Data Envelopment Analysis (DEA) models assuming: constant returns to scale (CRS), variable returns to scale (VRS) and slacks-based measures (SBM), respectively. We discuss how the proposed approach can provide real estate managers and analysts a multi informational tool that allows the quantification of targets and may serve as a guide tool for the efficient employment of real estate assets
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