13,911 research outputs found
Educational effectiveness and improvement in developing societies. Some experiences from the Primary Education Quality Improvement Project in Indonesia
The improvement of education in developing societies might benefit from theory and research on educational effectiveness. ... The research evidence points at the importance of factors at the classroom level and the relatively small possibilities that the school and the above school level have to influence those factors at the classroom level. This is illustrated by the evaluation of the primary education quality improvement project in Indonesia, a project that aimed at the improvement of education through teacher professional development, provision of textbooks, community participation and management of schools. The results tend to support the general feeling about educational effectiveness. Conclusions stress the importance of the development of knowledge by (inter)national consultants, the content of the intervention - educational effectiveness and improvement and the adaptation of the knowledge to national and local circumstances - and procedural and technical knowledge how to design, implement and evaluate educational interventions. (DIPF/orig.
Measuring Productivity Change without Neoclassical Assumptions: A Conceptual Analysis
The measurement of productivity change (or difference) is usually based on models that make use of strong assumptions such as competitive behaviour and constant returns to scale. This survey discusses the basics of productivity measurement and shows that one can dispense with most if not all the usual, neoclassical assumptions. By virtue of its structural features, the measurement model is applicable to individual establishments and aggregates such as industries, sectors, or economies.
A large-deviations analysis of the GI/GI/1 SRPT queue
We consider a GI/GI/1 queue with the shortest remaining processing time
discipline (SRPT) and light-tailed service times. Our interest is focused on
the tail behavior of the sojourn-time distribution. We obtain a general
expression for its large-deviations decay rate. The value of this decay rate
critically depends on whether there is mass in the endpoint of the service-time
distribution or not. An auxiliary priority queue, for which we obtain some new
results, plays an important role in our analysis. We apply our SRPT-results to
compare SRPT with FIFO from a large-deviations point of view.Comment: 22 page
Technological catch-up and strategic technology partnering in developing countries
This paper examines the trends in strategic technology partnering (STP) by firms from developing countries over the period 1980-94. The evidence shows that a small group of countries, namely the Asian NICs and Eastern Europe dominate STP activity. We also examine differences in organisational modes and how these have evolved over time, suggesting an increasing similarity between the NICs and Triad firms. Although it has been argued that these trends demonstrate the technological and economic falling behind of most developing countries, we suggest that it may also represent fundamental differences in the economic structure of these countries and the normal process of structural upgrading with development.research and development ;
First-order logic learning in artificial neural networks
Artificial Neural Networks have previously been applied in neuro-symbolic learning to learn ground logic program rules. However, there are few results of learning relations using neuro-symbolic learning. This paper presents the system PAN, which can learn relations. The inputs to PAN are one or more atoms, representing the conditions of a logic rule, and the output is the conclusion of the rule. The symbolic inputs may include functional terms of arbitrary depth and arity, and the output may include terms constructed from the input functors. Symbolic inputs are encoded as an integer using an invertible encoding function, which is used in reverse to extract the output terms. The main advance of this system is a convention to allow construction of Artificial Neural Networks able to learn rules with the same power of expression as first order definite clauses. The system is tested on three examples and the results are discussed
Introduction to Price and Productivity Measurement for Housing
This paper provides a brief introduction to a proposed new opportunity cost treatment of owner occupied housing in measures of inflation for the United States. In addition, the paper introduces, and provides links to, a collection of nine other papers that discuss various aspects of the treatment of owner occupied housing in measures of inflation for a number of nations including Canada, Germany, Iceland and the United States.Durable goods, Consumer Price Index, Cost of Living Index, Owner Occupied Housing, depreciation, hedonic regression models, rental equivalence approac
Controlling skyrmion bubble confinement by dipolar interactions
Large skyrmion bubbles in confined geometries of various sizes and shapes are
investigated, typically in the range of several micrometers. Two fundamentally
different cases are studied to address the role of dipole-dipole interactions:
(I) when there is no magnetic material present outside the small geometries and
(II) when the geometries are embedded in films with a uniform magnetization. It
is found that the preferential position of the skyrmion bubbles can be
controlled by the geometrical shape, which turns out to be a stronger influence
than local variations in material parameters. In addition, independent
switching of the direction of the magnetization outside the small geometries
can be used to further manipulate these preferential positions, in particular
with respect to the edges. We show by numerical calculations that the observed
interactions between the skyrmion bubbles and structure edge including the
overall positioning of the bubbles are fully controlled by dipole-dipole
interactions
Absorption and generation of femtosecond laser-pulse excited spin currents in non-collinear magnetic bilayers
Spin currents can be generated on an ultrafast timescale by excitation of a
ferromagnetic (FM) thin film with a femtosecond laser-pulse. Recently, it has
been demonstrated that these ultrafast spin currents can transport angular
momentum to neighbouring FM layers, being able to change both the magnitude and
orientation of the magnetization in the adjacent layer. In this work, both the
generation and absorption of these optically excited spin currents are
investigated. This is done using non-collinear magnetic bilayers, i.e. two FM
layers separated by a conductive spacer. Spin currents are generated in a Co/Ni
multilayer with out-of-plane (OOP) anisotropy, and absorbed by a Co layer with
an in-plane (IP) anisotropy. This behaviour is confirmed by careful analysis of
the laser-pulse induced magnetization dynamics, whereafter it is demonstrated
that the transverse spin current is absorbed very locally near the injection
interface of the IP layer (90% within the first approx. 2 nm). Moreover, it
will also be shown that this local absorption results in the excitation of THz
standing spin waves within the IP layer. The dispersion measured for these high
frequency spin waves shows a discrepancy with respect to the theoretical
predictions, for which a first explanation involving intermixed interface
regions is proposed. Lastly, the spin current generation is investigated using
different number of repeats for the Co/Ni multilayer, which proves to be of
great relevance for identifying the optical spin current generation mechanism
Spatial opinion dynamics and the effects of two types of mixing
Spatially situated opinions that can be held with different degrees of conviction lead to spatiotemporal patterns such as clustering (homophily), polarization, and deadlock. Our goal is to understand how sensitive these patterns are to changes in the local nature of interactions. We introduce two different mixing mechanisms, spatial relocation and nonlocal interaction (“telephoning”), to an earlier fully spatial model (no mixing). Interestingly, the mechanisms that create deadlock in the fully spatial model have the opposite effect when there is a sufficient amount of mixing. With telephoning, not only is polarization and deadlock broken up, but consensus is hastened. The effects of mixing by relocation are even more pronounced. Further insight into these dynamics is obtained for selected parameter regimes via comparison to the mean-field differential equations
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