5,199 research outputs found
The Italian Pension Gap: a Stochastic Optimal Control Approach
We study the gap between the state pension provided by the Italian pension
system pre-Dini reform and post-Dini reform. The goal is to fill the gap
between the old and the new pension by joining a defined contribution pension
scheme and adopting an optimal investment strategy that is target-based. We
find that it is possible to cover, at least partially, this gap with the
additional income of the pension scheme, especially in the presence of late
retirement and in the presence of stagnant career. Workers with dynamic career
and workers who retire early are those who are most penalised by the reform.
Results are intuitive and in line with previous studies on the subject
Microcracking in piezoelectric materials by the Boundary Element Method
A 3D boundary element model for piezoelectric polycrystalline micro-cracking is discussed in this contribution. The model is based on the boundary integral representation of the electro-mechanical behavior of individual grains and on the use of a generalized cohesive formulation for inter-granular micro-cracking. The boundary integral formulation allows to address the electro-mechanical boundary value problem in terms of generalized grain boundary and inter-granular displacements and tractions only, which implies the natural inclusion of the cohesive laws in the formulation, the simplification of the analysis pre-processing stage, and the reduction of the number of degrees of freedom of the overall analysis with respect to other popular numerical methods
Social safety nets in World Bank lending and analytical work : FY2002 - 2007
This paper summarizes the state of the portfolio of World Bank lending activities and analytic work on social safety nets between FY2002-2007. It presents a description of the methodology used for compiling the inventories and analyses by region, type of intervention involved, sector board, and instrument. The World Bank has engaged with 118 countries on safety nets issues over the six years under review, providing lending in 68, analytic products in 86, training in 87, and a combined package of all three services in 42, demonstrating the increased sophistication and the important role of safety nets in social policy. There is noticeable variability over time as the portfolio and analytic effort expand when large or multiple countries face economic crises. The regional distribution of safety net activities shows the dominance of Latin America. The analysis also shows the diversity within the portfolio, with respect to both the type of intervention supported and the range of sectors involved in safety net work. Finally, the report delineates the implications and outlook for the future.Safety Nets and Transfers,Banks&Banking Reform,,Labor Policies,Debt Markets
A Model for Configuration Management of Open Software Systems
The article proposes a model for the configuration management of open
systems. The model aims at validation of configurations against given
specifications. An extension of decision graphs is proposed to express
specifications. The proposed model can be used by software developers to
validate their own configurations across different versions of the components,
or to validate configurations that include components by third parties. The
model can also be used by end-users to validate compatibility among different
configurations of the same application. The proposed model is first discussed
in some application scenarios and then formally defined. Moreover, a type
discipline is given to formally define validation of a configuration against a
system specificationComment: 13 page
Highly labor-intensive public works in Madagascar : issues and policy options
High labor intensive (HIMO) public works programs have been very popular in recent years in Madagascar. They have been one of the most common safety net programs used in Madagascar to address poverty and vulnerability. The objectives of these programs are to provide income support to the poor after natural disasters and during seasonal agricultural employment slack period (soudure), and to improve much needed local infrastructures. This paper assesses the effectiveness of HIMO interventions in addressing the needs of poor and vulnerable households using the data from 15 projects implemented between 2006 and 2008 by several agencies. The main finding of this study is that despite their great potential, HIMO projects have shown the following limitations in the Madagascar context: a) lack of coordination among projects implemented by different agencies; b) ineffective targeting and poor selection of projects; c) lack of monitoring and supervision. The paper identifies four areas for improvement: a) better harmonization and coordination of HIMO projects to ensure consistency of approaches among interventions; b) better geographical targeting and selection of projects; c) setting the wage rate according to the local socio-economic conditions to promote self selection of the poor; and d) better collection of information for monitoring and evaluation of the impact of projects.Housing&Human Habitats,Rural Poverty Reduction,Population Policies,,Poverty Monitoring&Analysis
Urban and regional land use analysis: CARETS and Census Cities experiment package
The author has identified the following significant results. Areas of post 1970 and 1972 land use changes were identified solely from the Skylab imagery from comparisons with 1970 land use maps. Most land use changes identified involved transition from agriculture to single family residential land use. The second most prominent changes identified from the Skylab imagery were areas presently under construction. Post 1970 changes from Skylab were compared with the 1972 changes noted from the high altitude photographs. A good correlation existed between the change polygons mapped from Skylab and those mapped from the 1972 high altitude aerial photos. In addition, there were a number of instances where additional built-up land use not noted in the 1972 aerial photo as being developed were identified on the Skylab imagery. While these cases have not been documented by field observation, by correlating these areas with the appearance of similar land use areas whose identity has been determined, we can safely say that we have been able to map further occurrences of land use change beyond existing high altitude photo coverage from the Skylab imagery. It was concluded that Skylab data can be used to detect areas of land use change within an urban setting
Towards modular verification of pathways: fairness and assumptions
Modular verification is a technique used to face the state explosion problem
often encountered in the verification of properties of complex systems such as
concurrent interactive systems. The modular approach is based on the
observation that properties of interest often concern a rather small portion of
the system. As a consequence, reduced models can be constructed which
approximate the overall system behaviour thus allowing more efficient
verification.
Biochemical pathways can be seen as complex concurrent interactive systems.
Consequently, verification of their properties is often computationally very
expensive and could take advantage of the modular approach.
In this paper we report preliminary results on the development of a modular
verification framework for biochemical pathways. We view biochemical pathways
as concurrent systems of reactions competing for molecular resources. A modular
verification technique could be based on reduced models containing only
reactions involving molecular resources of interest.
For a proper description of the system behaviour we argue that it is
essential to consider a suitable notion of fairness, which is a
well-established notion in concurrency theory but novel in the field of pathway
modelling. We propose a modelling approach that includes fairness and we
identify the assumptions under which verification of properties can be done in
a modular way.
We prove the correctness of the approach and demonstrate it on the model of
the EGF receptor-induced MAP kinase cascade by Schoeberl et al.Comment: In Proceedings MeCBIC 2012, arXiv:1211.347
Census Cities experiment in urban change detection
The author has identified the following significant results. Mapping of 1970 and 1972 land use from high-flight photography has been completed for all test sites: San Francisco, Washington, Phoenix, Tucson, Boston, New Haven, Cedar Rapids, and Pontiac. Area analysis of 1970 and 1972 land use has been completed for each of the mandatory urban areas. All 44 sections of the 1970 land use maps of the San Francisco test site have been officially released through USGS Open File at 1:62,500. Five thousand copies of the Washington one-sheet color 1970 land use map, census tract map, and point line identification map are being printed by USGS Publication Division. ERTS-1 imagery for each of the eight test sites is being received and analyzed. Color infrared photo enlargements at 1:100,000 of ERTS-1 MSS images of Phoenix taken on October 16, 1972 and May 2, 1973 are being analyzed to determine to what level land use and land use changes can be identified and to what extent the ERTS-1 imagery can be used in updating the 1970 aircraft photo-derived land use data base. Work is proceeding on the analysis of ERTS-1 imagery by computer manipulation of ERTS-1 MSS data in digital format. ERTS-1 CCT maps at 1:24,000 are being analyzed for two dates over Washington and Phoenix. Anniversary tape sets have been received at Purdue LARS for some additional urban test sites
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