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Ceramic technology between the third and second millennium BC: New insights from southern Mesopotamia
This paper is the result of a pilot project conducted at the Penn Museum in Philadelphia and based on a selection of pottery vessels from Nippur (area TB) dated at the transition between the late Akkadian and Isin-Larsa period (2350-1763 BC). The continuity in occupation, and the presence of precise chronological markers make area TB a perfect case study for a diachronic analysis of the ceramic repertoire of this period. The aim of the project is a detailed reconstruction of the chaîne opératoire, fundamental for understanding the pottery repertoire from a technological point of view. Focusing on the late third millennium BC pottery assemblage, the chaîne opératoire approach can be used to discern the organisation and scale of production and the transmission of technical and technological knowledge through time, thus linking pottery production to the economic and social spheres. Macro- and meso-scale observations of pottery allow the identification of manufactural evidences useful for a preliminary reconstruction of the production sequence. Through this approach some aspects of continuity and discontinuity emerged, among which the identification of a new technique (trimming) at the very beginning of the second millennium BC, which can indicate significant technological development in pottery production
Eksperimentalno ponašanje prototipa matričnog pretvarača izvedenog s novim energetskim modulima
This paper describes the design and the solutions adopted for a matrix converter prototype of 10 kW, based on new integrated power modules. The performance of the converter is verified by means of experimental tests.Članak opisuje projekt i rješenja usvojena za prototip 10 kW matričnog pretvarača, izvedenog s novim integriranim energetskim modulima. Svojstva pretvarača provjerena su eksperimentalnim ispitivanjima
Exponential stabilization of infinite-dimensional systems by finite-dimensional controllers
This paper studies the feedback stabilization of abstract Cauchy problems
with unbounded output operators by finite-dimensional controllers. Both
necessary conditions and sufficient conditions for feedback stabilizability are
presented. The proof of closed-loop stability is based on a novel input-output
gain introduced in this paper. For systems satisfying a property we call
quasi-finite, an equivalent characterization of feedback stabilizability is
obtained. Quasi-finiteness is verified for classes of parabolic and hyperbolic
equations
An analytic-geospatial approach for sustainable water resource management: a case study in the province of Perugia
Water is a strategic, but also highly vulnerable, natural resource. This because the increasing demand from multiple uses, in many cases competing amongst them, seems to influence the concepts of sustainability of the exploitation. From the operational point of view, the studied system is an integrated decision support system. It is not only a platform to exchange information and assessments, but also a tool for conflict resolution, in the management of water resources, to obtain the consensus among all participants in the decisional processes. So the canonical “top-down” approach has been replaced with a “bottom-up” approach where all stakeholders become decision makers themselves. The application of the aforementioned approach was studied for the Tiber River basin and has been applied to the Province of Perugia area. The study focused to the building of a spatial database of hydrological data and multipurpose water withdrawals, together with the setting of the evaluation model for the surface water resources. This model bases its algorithms on regionalization procedures of flow parameters. For the definition of the river condition, hydrological indices calculated from the hydrological database have been used, while for the existing withdrawals, an analysis procedure has been developed, that from the point of interest directly selected on the map, finds out the upstream basin and, by means of overlay procedures, identifies the upstream water uses and the total flow that could be extracted. The potential of the system and the technologies used are contained in a WEB platform that allows the analysis of the database of water uses/withdrawals on the cartography, and the comparison with the hydrogeological characteristics of the sub-basin examined. The purpose of this study is to provide software tools that can be used as a support in water resource evaluation and management policies at the basin scale
Impiego di regolatori ripetitivi per il controllo di convertitori elettronici di potenza per l'interfacciamento con la rete elettrica
L’obiettivo di tesi consiste nel valutare il funzionamento di regolatori ripetitivi per il controllo di un inverter utilizzato come filtro attivo al fine di eliminare le armoniche di corrente prodotte da un carico distorcente trifase connesso in rete.
È descritto lo schema di simulazione realizzato in ambiente Simulink di Matlab per poter individuare una possibile implementazione del controllo. È descritta l’attività di prototipazione rapida svolta mediante il sistema dSPACE per poter verificare sperimentalmente il funzionamento del controllo con regolatore ripetitivo su un modello di impianto reale costituito da inverter, carico distorcente e rete
Agronomical evaluation and chemical characterization of Linum usitatissimum L. as oilseed crop for bio-based products in two environments of Central and Northern Italy
In the recent years, new perspectives for linseed (Linum usitatissimum
L.) are open as renewable raw material for bio-based products
(Bb), due to its oil composition, and the interesting amounts of coproducts
(lignocellulosic biomass). Therefore, the possibility to introduce
linseed crop in two environments of central and northern Italy,
traditionally devoted to cereal cultivation, has been evaluated. Twoyears
field trials were carried out in the coastal plain of Pisa (Tuscany
region) and in the Po valley (Bologna, Emilia Romagna region), comparing
two linseed varieties (Sideral and Buenos Aires). Agronomical
evaluation (yield and yield components), seed and oil characterization
(oil, protein content, and fatty acid composition), together with carbon
(C) and nitrogen (N) content of the residual lignocellulosic biomass
were investigated. The two varieties, grown as autumn crop, showed a
different percentage of plant survival at the end of winter, with Sideral
most resistant to cold. The achieved results showed significant influence
of cultivar, location and growing season on yield and yield components,
as well as on chemical biomass composition. In particular,
Sideral appeared to be the most suitable variety for tested environments,
since higher seed yield (3.05 t ha–1 as mean value over years
and locations) and above-ground biomass (6.98 t ha–1 as mean value
over years and locations) were recorded in comparison with those
detected for Buenos Aires (1.93 and 4.48 t ha–1 of seed production and
lignocellulosic biomass, respectively). Interestingly, in the northern
area, during the 1st year, Buenos Aires was the most productive,
despite its low plant survival at the end of winter, which determined a
strong reduction in plant density and size. In such conditions, the
plants produced a larger number of capsules and, consequently, high
seed yield (3.18 t ha–1). Relevant differences were also observed
between the two years, due to the variability of climatic characteristics
(temperature levels, and moisture regimes). All these findings confirmed
as, in linseed, yield and yield components are quantitatively
inherited and influenced by both genotype and environment (location
and climate). Varietal and environmental effects were also recorded
for oil content and yield, and, generally, good oil percentages, for both
genotypes, were found (ranging from 44 to 49% on dry matter basis).
Oil from the two varieties was characterized by a stable proportion of
polyunsaturated fatty acids with a high content of alpha-linolenic acid
(more than 57%), that makes this oil suitable to be used in paints,
resins, varnishes, linoleum, polymers and oleochemicals. Finally, our
results pointed out as above- and below-ground biomasses, were different
in terms of quantity, and chemical characteristics (N, C and C/N
ratio). Interesting amounts of N and C could return into the soil by
crop residues (stem portions and roots), thus underling the possibility
to maintain and/or increase the soil organic matter pool
Radioembolization versus chemoembolization for unresectable hepatocellular carcinoma: a meta-analysis of randomized trials
PURPOSE:
This study aimed to compare clinically relevant outcomes following transarterial chemoembolization (TACE) and transarterial radioembolization (TARE) in patients with unresectable hepatocellular carcinoma (HCC) using only prospective randomized clinical trials as a source of information.
MATERIALS AND METHODS:
A meta-analysis was performed to compare the efficacy of TARE and TACE in treating patients with unresectable HCC. Only prospective randomized trials were included in the quantitative analysis. Overall and progression-free survival, disease control rate, and transplantation rate were the variables under analysis.
RESULTS:
Overall survival at 1 year was similar between the two treatment groups (OR =1.31, 95% CI: 0.56-3.04, P=0.53). Progression-free survival at 1 year was also not statistically different between the two treatments (OR =0.23, 95% CI: 0.02-2.45, P=0.22). Although a higher proportion of patients underwent transplantation in the TARE group (30% vs 20.8%), this difference was not statistically significant (OR =0.68, 95% CI: 0.23-2.01; P=0.49).
CONCLUSION:
TARE and TACE provide similar outcomes in unresectable HCC. The role of TARE should be explored in selected patient subpopulations in future clinical trials
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