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Risk of Relapse: Somalia crisis update
No full textWith a third of Somalia’s population in need of humanitarian aid, the country is clearly in severe crisis. Although the humanitarian statistics are better than in previous years, most aspects of everyday life for people fall far below acceptable living standards. The paper presents an update of this crisis in Somalia.Dadweynaha soomaaliyeed saddex kameelood meel waxay u baahanyihiin gargaar aadami, dalku wuxuu marayaa xaalad halis ah. Inkastoo tirakoobka gargaarka aadamigu uu dhaamo midka sannadihii hore, haddan dadka intooda badan, hab nololeedkoodu aad buu uga hooseeyaa midka caadiga ah. Maqaalku wuxuu si cusub u muujinayaa dhibaatadaan haysa dalka soomaaliyeed.Con un terzo della popolazione della Somalia bisognosa di aiuti umanitari, il paese attraversa una grave crisi. Anche se le statistiche umanitarie sono migliori rispetto agli anni precedenti, la maggior parte degli aspetti della vita quotidiana per le persone sono lontane dagli standard di vita accettabili. L'articolo presenta un aggiornamento di questa crisi della Somalia
Halqooq Saar
No full textSaarkani waa saar Islaami ah, oo loo tiriyey in lagu cabbiro arrima dhowr ah oo ku saabsan ku hanuunin tubta toosan ee Islaamka. Ujeeddada guud ee gabyaagu saarkan la leeyahay waxay tahayse in afsoomaaligu u baahnayn erayo carabi ah si uu farriin diin u xambaaro, sida wadaaddada soomaaliyeed inta badan sameeyaan.Il poeta compose e recitò questo saar di contenuto religioso con lo scopo di trattare vari argomenti relativi all'esortazione alla retta via rappresentata dall’Islam. Lo scopo principale è quello di sottolineare che la lingua somala ha bisogno di terminologia araba per poter esprimere concetti e messaggi religiosi, come facevano e fanno tuttora gli uomini religiosi somali.The poet composed and recited this saar of religious content with the aim of talking about different themes related to the exhortation to the righteous path represented by the Islam. The main aim is highlighting that Somali language needs Arabic terminology in order to be able of express religious concepts and messages, as Somali religious men used to do and still do.https://www.youtube.com/watch?v=7sEJuTwA_vM&feature=youtu.b
Higher order isogeometric BEM for high accuracy simulations in acoustics
No full textIn the present work we developed five different not approximated BEM higher{
order approaches for the solution of the 2D and 3D acoustic problem, validating
them against analytical solution, where available, and performing a convergence
analysis. The different approaches explored in this work are:
-2D Hermite (classic approach)
-2D Hermite Dual
-3D Hermite Coons
-3D Hermite Coons Dual (preliminary implementation)
-2D Nurbs
We explored algorithms based mostly on Hermite splines. The presence of the
nodal derivatives in the representation of the variables, has been taken into account
both with a \classic approach", where those derivatives are expressed with a finite
differences scheme in terms of the nodal values and with a so called \dual approach"
where the same derivatives are considered as unknown of the problem and the linear
system is completed by the tangential gradient of the integral equation.
The Hermite based higher order representations, also coupled with Coons
patches to avoid the introduction of the mixed derivatives, although achieving
a higher rate of convergence than O(h), are limited to a single order.
In order to overcome the single{order limitation of the Hermite based BEM
methods we also explored an approach based on Non Uniform Rational Basis{
Splines (NURBS). By using a global representation of the variables based on
NURBS, the order of the basis functions can be improved at runtime when needed
by the specific application at hand. This is a consequence of the iterative definition
of the NURBS, which makes possible the increase of the NURBS degree simply
by changing an input parameter. The use of the NURBS for the representation of
curves and surfaces is a common technique in the CAD community for the model-
ing of complex geometries with strict requirements of smoothness and continuity
between patches. Their use in the numerical solution of BIE is not new, although
relatively recent. NURBS have been used to develop boundary element solutions
of integral equations in elastostatics, in radiation and diffraction problems, and
in potential aerodynamics. The peculiarity of this approach is in the use of the
NURBS for the development of a global isogeometric approach aimed at the mesh-
less numerical solution of the BVP. The control points used for the representation
of the dependent variables are obtained through the h-refinement of the optimal
NURBS representation of the geometry.
In the work we outline the underlying theory for the acoustic problem and for
the BEM methodology, we illustrate the above said approaches in detail and we
show how the high order methods described in this work are an effective tool to
the simulation of high accuracy phenomena such as the ones involving the acoustic
analysis of phononic crystals
User-assisted synergic crawling and wrapping for entity discovery in vertical domains
No full textLarge data-intensive web sites publish considerable quantities of information
stored in their structured repositories. Data is usually rendered in numerous data-
rich pages using templates or automatic scripts. This wealth of information is
of wide interest to many applications and online services that do not have direct
access to the structured data repositories. Therefore, there’s a great need to lo-
cate such pages, accurately and efficiently extract data on them, and store it in a
structured format more adapted to automatic processing than HTML.
In this context, we exploit intra- and inter-web site information redundancy to
address the problem of locating relevant data-rich pages and inferring wrappers on
them, while incurring a minimum user overhead. In the first part, we propose to
model large data-intensive web sites, to crawl only the subset of pages pertaining
to one vertical domain, and then build effective wrappers for attributes of interest
on them, with minimum user effort. Our methodology for synergic specification
and execution of crawlers and wrappers is supported by a working system devoted
to non-expert users, built over an active-learning inference engine.
In the second part, we use the information gathered during inference on the
training site, to automatically discover new similar sources on the same type of
entities of the vertical domain, which can be useful to complement, enrich, or ver-
ify the collected data. Our proposed approach performs an automated search and
filter operation by generating specific queries and analyzing the returned search
engines results. It combines exploiting existing attributes, template, and page
information with a semantic, syntactic, and structural evaluation of newly discov-
ered pages to identify relevant semi-structured sources.
Both techniques are validated with extensive testing on a variety of sources
from different vertical domains
A memetic NSGA-II for bi-objective mixed capacitated general routing problem
No full textThe Mixed Capacitated General Routing Problem (MCGRP) is concerned with the determination
of the optimal vehicle routes to service a set of customers located at nodes
and along edges/arcs on a mixed weighted graph representing a complete distribution
network. Although using nodes, edges and arcs simultaneously yields better models for
many real-life vehicle routing problems such as newspaper delivery and urban waste
collection, very few research works have been dedicated since the MCGRP was defined.
Furthermore, most of the studies have focused on the optimization of just one
objective, that is, cost minimization. Keeping in mind the requirements of industries
nowadays, MCGRP has been addressed in this thesis to concurrently optimize two crucial
objectives, namely, minimization of routing cost and route balance (the difference
between the largest route and the smallest route with respect to duration). To solve this
bi-objective form of the MCGRP, a multi-objective evolutionary algorithm (MOEA),
coined as Memetic NSGA-II, has been designed. It is a hybrid of non-dominated sorting
genetic algorithm-II (NSGA-II), a dominance based local search procedure (DBLSP)
and a clone management principle (CMP). The DBLSP and CMP have been incorporated
into the framework of NSGA-II with a view to empowering its capability to
converge at/or near the true Pareto front and boosting diversity among the trade-off solutions.
In addition, the algorithm also contains a set of three well-known crossover
operators (X-set) that are employed to explore different parts of the search space. It was
tested on twenty three instances simulating real-life situations and of varying complexity.
The computational experiments verify the effectiveness of the Memetic NSGA-II
and also show the energetic effects of using DBLSP, CMP and X-set together while
finding the set of potentially Pareto optimal solutions
Advanced techniques for mapping and cleaning
No full textWe address the challenging and open problem of bringing together two
crucial activities in data integration and data quality, i.e., transforming data
using schema mappings, and fixing conflicts and inconsistencies using
data repairing.
This problem is made complex by several factors. First, schema mappings
and data repairing have traditionally been considered as separate activities,
and research has progressed in a largely independent way in the two fields.
Second, the elegant formalizations and the algorithms that have been
proposed for both tasks have had mixed fortune in scaling to large
databases. In the thesis, we introduce a very general notion of a mapping
and cleaning scenario that incorporates a wide variety of features, like, for
example, user interventions.
We develop a new semantics for these scenarios that represents a
conservative extension of previous semantics for schema mappings and
data repairing. Based on the semantics, we introduce a chase-based
algorithm to compute solutions. Appropriate care is devoted to developing
a scalable implementation of the chase algorithm. To the best of our
knowledge, this is the first general and scalable proposal in this direction
Assessing Sapienza University alumni job careers : enhanced partial least squares latent variable path models for the analysis of the UNI.CO administrative archive
No full textFor several years, the Italian universities have been urged to better understand the characteristics of labour demand for their alumni. For this purpose periodic reports
of the results of sample surveys are produced by institutions or private entities.
These studies are detected directly from the alumni and their employment status after graduation (the most common sample surveys coming from Inter-University Consortium AlmaLaurea). These results constitute important information for students, families and universities. The sample surveys are based on studies that take place at a distance of six months and of two years from the date of graduation. The alumni are interviewed regarding their satisfaction as well as to obtain information on their employment situation. Obviously, all ex post assessments provide us with a lot of information to define overall judgements regarding the educational career but also their employment status.
Of course, the definition of a graduate's employment status is not unique. With
regards to Italy, the ISTAT records the status of employment when the individual performs, in a reference week, at least one hour of paid work (regulated by a registered contract) regardless of the type of contract and the regularity of employment.
Timing is certainly a critical element: studies too close to the end of the educational
experience do not sufficiently reect the students' rethinking of their educational
lives. However, if the surveys are too far from this experience, the rethinking can itself be strongly influenced by exogenous factors.
The labour market demand for the employability skills and knowledge of Sapienza graduates can now be analysed through the new administrative archive called UNI.CO, which was built through a record-linkage between the Sapienza University of Rome archive with those of the Italian Ministry of Labour and Social Policy. The UNI.CO archive has allowed us to evaluate all the signed contracts obtained by Sapienza
graduates in addition to full information on all the enterprises and institutions that
offered these contracts. This archive allows us to perform a statistical analysis on more sophisticated and robust (and more reliable) details than the standard analysis based on sample surveys. In our study we have, therefore, used objective real data unaffected by any emotional influence. Another important feature is that the data from the UNI.CO archive allow us to study the evolution of alumni throughout the observation period and therefore to analyse changes in job qualifications (differently from the common sample survey supply information about the status of alumni at some fixed point in time (like a photograph)).
In this thesis we adopted the administrative UNI.CO archive in order to be able to present the theme of the integration of Sapienza University of Rome alumni into the employee and para-subordinate labour market with more sophisticated and powerful details in relation to the standard analysis based on sample surveys. Moreover, the data of the UNI.CO archive allow us to also study the evolution of alumni throughout the observation period and therefore to analyse the changes in job qualifications. The study of the integration into the labour market of Sapienza alumni has been analysed by adopting the Non-Metric PLSPM method which allows us to handle a large dataset with numerical, nominal and ordinal variables. This technique recently proposed by Russolillo (2012) and now available in the plspm R-package, is characterized by the opportunity to analyse at the same time variables observed in different measurement scales, to investigate the non linearity and to work without distributional hypotheses. The Non-Metric PLSPM has demonstrated a remarkable
adaptability to handle the UNI.CO large dataset and we have found that the quantifications of the original data obtained by the procedure are properly carried out using monotone transformations showing the remarkable fact that it is possible to discard the hard assumption of linearity in favor of the milder assumption of monotonicity.
In this thesis, we have modified the inner structure of the Non-Metric PLSPM to implement the possibility of modeling binary endogenous latent variables through a logistic regression and then we have introduced the ROC curve for the model validation. This implementation is applicable in the case of blocks with only one MV and this is binary, therefore LVs have a binary structure and the weight and the
loading are unitary.
We have addressed the study of the integration into the labour market of Sapienza alumni by developing a few models.
The first one concerns the quantitative study of the job success of the masters degree alumni of the Sapienza University who belong to the engineering disciplinary sector in terms of quality of work. In particular, we studied indicators of job success to estimate their relationships with educational and job curriculum. These indicators have been constructed defining the concept of optimal contract based on a contract with the characteristics of permanent position, highly qualified professional position identified using the ISCO classification and the actual duration more than or equal to 8 months. The concept of quasi-optimal contract is similar to the optimal definition without the condition of permanent position. The high values of the measurement model have confirmed that the optimal and quasi-optimal indicators are
discriminant to the construction of the Job Success block.
The second and the third models have been built in order to study the job career in terms of the contract type and quality evolution in the three years after graduation. For these studies we selected from the UNI.CO dataset, independently from the disciplinary group, two sets of data: alumni who at the time of the master's degree had not yet obtained an active contract (non-workers studied by the second
model) and alumni who at the time of the master's degree had obtained an active contract (workers studied by the third model). The main purpose we addressed is to model, in the PLS-PM framework, the contract type and job professional quality evolution as latent variables to be studied in relation to educational curriculum, age, initial experience and tendency to evolve. The two models adopted consist essentially of four concepts: the university evaluation, the initial job experience, tendency to evolve and the career evolution. The career evolution is monitored by two constructs: one for the job professional evolution and the other for the job contractual
evolution. We have found that in both the models there is a strong influence of the
initial job experience and of the tendency to evolve over the job career, while the university evaluation at the level of the master's degree is less important. The age
at the master's degree has a marginal effect in the model for non-workers while it disappears for workers.
It is remarkable that the implementation of the logistic regression, in all the presented models, has shown a good classification measured in terms of high AUC values.
The overall frame that arises from these studies is that when there is a natural individual aptitude of the alumni to change job, this tendency plays a positive important
role with the aim of obtaining a satisfactory job; on the other hand, the university
path of Sapienza alumni does not seem to have a large direct influence on their job career.
It is clear that our analysis can be considered as a starting point for further studies aimed to investigate the relationships between the world of labour and that of the university education in order to improve the efforts that should be made to integrate these two worlds
Exploring the links between agricultural biodiversity, ecosystem services and human well-being : evidence from the Yucatan, Mexico
No full textThis study hypothesises that the application of an integrated and multidimensional human well-being - ecosystem approach can improve our understanding of agricultural biodiversity
and the ecosystem services it provides in terms that are meaningful to the people that depend
on them, allowing us to draw relevant policy implications. We develop an Extended-
Capability-Ecosystem-Approach based on Duraiappah (2004) to analyze the relationship
between the conservation and use of agricultural biodiversity and different aspects of the well-being of households, including their conversion factors, capabilities and endowments.
The empirical focus is on farming households of the Yucatán, Mexico, where Mayan descendants depend on agricultural biodiversity and the ecosystem services it provides for their subsistence, food security, and culture, often within marginal economic and agronomic
conditions. The possible expansion of opportunities open to people through education and employment appears coupled with a process of ageing of the population working in agriculture and rural out-migration. The latter seems related to the use of higher crop diversity on farm and the conservation of local varieties, posing issues of future loss of
genetic resources, associated knowledge and cultural values. Geographical isolation also
appears to contribute to a higher level of crop diversity and a more intensive use of off farm
ecosystem goods. Finally, the work of women on farm is significantly associated with conservation of local varieties and higher crop diversity for consumption, indicating that
conservation strategies should take into account the gender dimension of associated
knowledge and preferred characteristics of varieties. It emerges that agrobiodiversity and
related ecosystem services represent fundamental safety nets, the basis for consumption stability and a risk diversification strategy, often linked to cultural and social practices, but the difficult condition of life in rural areas cannot be overlooked. The relationship between
socio-economic characteristics of households and agrobiodiversity calls for a more coherent
and concerted conservation strategy linking the action of development and environmental agencies. The recognition of the needs and aspirations of different groups in the population might favour the creation of appropriate incentives for the conservation of crop genetic resources on farm and the sustainable use of off farm ecosystem goods, expanding the real opportunities that people enjoy
Texte de l'accord de tutelle pour le territoire de la Somalie sous Administration Italienne
No full textQoraal ku saabsan heshiiska Maamulka walaayada taliyaaniga ee SoomaaliyaTesto dell'accordo di Amministrazione Fiduciaria italiana in Somalia.Text of the Italian Trusteeship in Somalia
Shaydaankii shayaadiinta
No full textBuuggani wuxuu jawaacelin kooban ka bixinayaa buuggii uu qoray Salman Rushdi oo halkudheggiisu ahaa "Aayadihii Shaydaanka".Il volume fornisce delle risposte al libro di Salman Rushdi intitolato "I versetti di Satana".The book provides answers to the book by Salman Rushdi titled "Verses of Satan.