3,111 research outputs found
Models of unionism and unemployment
No full textWe investigate the problem of simultaneous determination of labour market institutions and outcomes in single equation multi-country estimations by presenting an empirical analysis of unemployment and union density in 20 OECD countries. When explicitly modelling potential endogeneity and heterogeneity, our results suggest that unions contribute to explaining unemployment in different ways than previously thought. In addition, the relationship between unemployment and union density is heterogeneous across countries, depending on the way in which income support for the unemployed is organized
An assessment of the impact of possible CAP reform scenarios on Romanian agriculture
No full textUsing a simplified model, with key-variable the prices of two different possible scenarios of CAP reform after 2013 (moderate and radical), this paper present a comparison between the price effects of implementation of each reform scenario at 2015 horizon on Romanian agriculture. This short analysis shows that, under the presented hypotheses, the net welfare effect, due to the price changes, for the selected products, is positive in both reform scenarios, yet greater in the case of the radical reform. Integrated in the large context of Romanian development, it seems that the influence of CAP reform upon agriculture and rural areas will be most likely a gradual one: an interpenetration between the two scenarios is foreseeable, starting with the moderate reform that will dominate the period around 2013, the reform measures acquiring a more radical character afterwards.CAP reform, Romania, welfare effects, Agricultural and Food Policy,
Significance of a simplified method for periodontal risk assessment in predicting periodontitis recurrence during supportive periodontal therapy: a retrospective cohort study
No full textAim: To evaluate whether patient-related risk scores generated with a simplified method for periodontal risk assessment (UniFe; Trombelli et al. 2009) may predict periodontitis recurrence during supportive periodontal therapy (SPT).
Material and Methods: At 2 clinical centers, data were retrospectively obtained from the record charts of 109 patients (age range: 22–62 years). According to the individual treatment plan, patients had undergone active periodontal therapy (APT) and had been enrolled in a SPT program for a mean of 5.6 2.2 years. Patient-related risk scores referred to the first visit following APT were calculated on a scale from 1 (low risk) to 5 (high risk) according to UniFe. Patients were grouped according to risk scores and compared for tooth loss as well as
changes in radiographic bone levels and pocket probing depth (PPD) occurred during SPT.
Results: After APT, 5, 6, 20, 65, and 13 patients showed a risk score of 1, 2, 3, 4 and 5, respectively. The mean number of teeth lost during SPT ranged from 0 to 1.8 2.5 teeth in patients with a risk score of 1 and 5, respectively (p = 0.041), with a mean yearly rate between 0 (risk score 1) and 0.32 0.51 teeth/year (risk score 5) (p = 0.053). Mean bone loss and PPD increase during SPT were both ≤0.50 mm in all
risk groups, without inter-group differences.
Conclusion: Within its limits, the present study indicate that risk assessment according to the UniFe method may help to identify patients at risk for tooth loss during SPT
Impact of supportive periodontal therapy on periodontal prognosis as assessed with a simplified method for risk assessment: a retrospective cohort study
No full textAim: To evaluate the impact of supportive periodontal therapy (SPT) on periodontal prognosis, as assessed with a simplified method (UniFe; Trombelli et al. 2009). Material and Methods: At 2 clinical centers, data were retrospectively obtained from the record charts of 109 patients (age range: 22–62 years). According to the individual treatment plan, patients had undergone active periodontal therapy (APT) and had been enrolled in a SPT program for a mean period of 5.6 2.2 years. At the completion of APT (T1) and the most recent SPT visit (T2), patient-related periodontal risk scores were calculated according to UniFe on a scale from 1 (low risk) to 5 (high risk).
Results: The mean risk score was 3.7 0.9 and 3.7 1.0 at T1 and T2, respectively, with no significant difference between T1 and T2. Also, no significant difference in the distribution of patients according to risk score were observed between time intervals. Patient mobility through risk groups from T1 to T2 was observed, with 21% of patients showing a decrease in risk score (1 score: 16%; 2 scores: 3%; 3 scores: 2%), while 28% showing an increase (+1 score: 26%; +2 scores: 2%). The increase in risk scores was mainly due to an increase in the
severity and extension of bone loss and probing depths as well as an increase in full mouth bleeding scores. Conclusion: In general, SPT may be effective in preserving patient-related periodontal prognosis following APT. When occurs, worsening of periodontal prognosis is mainly due to the recurrence of the clinical signs of the disease
Rich, Sturmian, and trapezoidal words
No full textIn this paper we explore various interconnections between rich words, Sturmian words, and trapezoidal words. Rich words, first introduced by the second and third authors together with J. Justin and S. Widmer, constitute a new class of finite and infinite words characterized by having the maximal number of palindromic factors. Every finite Sturmian word is rich, but not conversely. Trapezoidal words were first introduced by the first author in studying the behavior of the subword complexity of finite Sturmian words. Unfortunately this property does not characterize finite Sturmian words. In this note we show that the only trapezoidal palindromes are Sturmian. More generally we show that Sturmian palindromes can be characterized either in terms of their subword complexity (the trapezoidal property) or in terms of their palindromic complexity. We also obtain a similar characterization of rich palindromes in terms of a relation between palindromic complexity and subword complexity
Characterization Results for the Poset Based Representation of Topological Relations - I: Introduction and Models
No full text@article{DBLP:journals/informaticaSI/ForlizziN99,
author = {Luca Forlizzi and
Enrico Nardelli},
title = {Characterization Results for the Poset Based Representation
of Topological Relations - I: Introduction and Models.},
journal = {Informatica (Slovenia)},
volume = {23},
number = {2},
year = {1999},
bibsource = {DBLP, http://dblp.uni-trier.de}
Characterization Results for the Poset Based Representation of Topological Relations - II: Intersection and Union
No full text@article{DBLP:journals/informaticaSI/ForlizziN00,
author = {Luca Forlizzi and
Enrico Nardelli},
title = {Characterization Results for the Poset Based Representation
of Topological Relations - II: Intersection and Union.},
journal = {Informatica (Slovenia)},
volume = {24},
number = {1},
year = {2000},
bibsource = {DBLP, http://dblp.uni-trier.de}
System-on-chip Computing and Interconnection Architectures for Telecommunications and Signal Processing
No full textThis dissertation proposes novel architectures and design techniques targeting SoC building blocks for telecommunications and signal processing applications.
Hardware implementation of Low-Density Parity-Check decoders is approached at both the algorithmic and the architecture level. Low-Density Parity-Check codes are a promising coding scheme for future communication standards due to their outstanding error correction performance.
This work proposes a methodology for analyzing effects of finite precision arithmetic on error correction performance and hardware complexity. The methodology is throughout employed for co-designing the decoder. First, a low-complexity check node based on the P-output decoding principle is designed and characterized on a CMOS standard-cells library. Results demonstrate implementation loss below 0.2 dB down to BER of 10^{-8} and a saving in complexity up to 59% with respect to other works in recent literature. High-throughput and low-latency issues are addressed with modified single-phase decoding schedules. A new "memory-aware" schedule is proposed requiring down to 20% of memory with respect to the traditional two-phase flooding decoding. Additionally, throughput is doubled and logic complexity reduced of 12%. These advantages are traded-off with error correction performance, thus making the solution attractive only for long codes, as those adopted in the DVB-S2 standard. The "layered decoding" principle is extended to those codes not specifically conceived for this technique. Proposed architectures exhibit complexity savings in the order of 40% for both area and power consumption figures, while implementation loss is smaller than 0.05 dB.
Most modern communication standards employ Orthogonal Frequency Division Multiplexing as part of their physical layer. The core of OFDM is the Fast Fourier Transform and its inverse in charge of symbols (de)modulation. Requirements on throughput and energy efficiency call for FFT hardware implementation, while ubiquity of FFT suggests the design of parametric, re-configurable and re-usable IP hardware macrocells. In this context, this thesis describes an FFT/IFFT core compiler particularly suited for implementation of OFDM communication systems. The tool employs an accuracy-driven configuration engine which automatically profiles the internal arithmetic and generates a core with minimum operands bit-width and thus minimum circuit complexity. The engine performs a closed-loop optimization over three different internal arithmetic models (fixed-point, block floating-point and convergent block floating-point) using the numerical accuracy budget given by the user as a reference point. The flexibility and re-usability of the proposed macrocell are illustrated through several case studies which encompass all current state-of-the-art OFDM communications standards (WLAN, WMAN, xDSL, DVB-T/H, DAB and UWB). Implementations results are presented for two deep sub-micron standard-cells libraries (65 and 90 nm) and commercially available FPGA devices. Compared with other FFT core compilers, the proposed environment produces macrocells with lower circuit complexity and same system level performance (throughput, transform size and numerical accuracy).
The final part of this dissertation focuses on the Network-on-Chip design paradigm whose goal is building scalable communication infrastructures connecting hundreds of core. A low-complexity link architecture for mesochronous on-chip communication is discussed. The link enables skew constraint looseness in the clock tree synthesis, frequency speed-up, power consumption reduction and faster back-end turnarounds. The proposed architecture reaches a maximum clock frequency of 1 GHz on 65 nm low-leakage CMOS standard-cells library. In a complex test case with a full-blown NoC infrastructure, the link overhead is only 3% of chip area and 0.5% of leakage power consumption.
Finally, a new methodology, named metacoding, is proposed. Metacoding generates correct-by-construction technology independent RTL codebases for NoC building blocks. The RTL coding phase is abstracted and modeled with an Object Oriented framework, integrated within a commercial tool for IP packaging (Synopsys CoreTools suite). Compared with traditional coding styles based on pre-processor directives, metacoding produces 65% smaller codebases and reduces the configurations to verify up to three orders of magnitude
GRUPPO MONTUORI
No full textLa scheda illustra il progetto redatto come gruppo di studio dell'Università degli Studi Roma Tre, Facoltà di architettura, nell'ambito della ricerca Nazionale PRIN sugli archivi di architettur
Prognostic value of a simplified method for periodontal risk assessment during supportive periodontal therapy
No full textAim: To evaluate the association between risk scores generated with a simplified method for periodontal risk assessment (Perio Risk), and tooth loss as well as bone loss during supportive periodontal therapy (SPT).
MATERIALS & METHODS:
Data related to 109 patients (42 males; mean age: 42.2 ± 10.2 years, range 22-62) enrolled in a SPT programme for a mean period of 5.6 years were retrospectively obtained at two specialist periodontal clinics. Patients were stratified according to Perio Risk score (on a scale from 1 - low risk to 5 - high risk) as calculated at the end of active periodontal therapy. Risk groups were compared for tooth loss as well as the changes in radiographic bone levels occurred during SPT.
RESULTS:
The mean number of teeth lost per patient during SPT varied from 0 to 1.8 ± 2.5 for patients with a risk score of 1 and 5 respectively (p = 0.041). Mean radiographic bone loss during SPT was ≤0.5 mm in all risk groups, without significant inter-group differences.
CONCLUSIONS:
Periodontal risk assessment according to Perio Risk may help to identify patients at risk for tooth loss during SPT
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