Search results for " processing"
showing 10 items of 7549 documents
The Cereal Market and the Role of Fermentation in Cereal-Based Food Production in Africa
2014
Cereals represent the main crop in Africa (45% of arable land) and make an important contribution to the human diet in this continent. Cereals for humans are not consumed raw. Fermentation technology is widely used in Africa to transform cereals into edible products as well as to preserve and enhance the nutritional and safety aspects of cereals. In general, in Africa, this process is not controlled and is devoid of good manufacturing practices (GMPs). Spoilage and/or pathogenic microorganisms may compromise the final quality when the fermentation is not controlled. This article focuses on the role that the fermentation process could play in creating safe food conditions in Africa. Taking i…
Processing Strategies to Inactivate Hepatitis A Virus in Food Products: A Critical Review
2015
Hepatitis A infection, caused by hepatitis A virus (HAV), is the leading cause of human viral hepatitis throughout the world and is mainly propagated via the fecal–oral route. Transnational outbreaks of food-borne infections are reported with increasing frequency as a consequence of international food trade. Food-borne outbreaks caused by HAV are mainly associated with bivalve molluscs, produce (soft fruits and leafy greens), and ready-to-eat meals. The purpose of this paper was to conduct a structured and systematic review of the published literature on the current state of knowledge regarding the stability of HAV in foods as well as the efficacy of food processing strategies and to identi…
Discovering temporal relationships in databases of newspapers
1998
This paper is mainly dedicated to analyse the problem of discovering frequent temporal patterns in event sequences extracted from a large repository of newspapers. The proposed formalism and algorithms rely on Toodor, which is a document retrieval system that allows users to specify conditions over the structure, contents and temporal features of the stored documents. We develop in this work several algorithms for recognising frequent temporal patterns in terms of arc-consistency, which consist of discarding temporal occurrences that do not satisfy a temporal structure.
A Novel Linear-Non-Linear Digital Control for DC/DC Converter with Fast Transient Response
2006
In this paper, a digitally controlled multimodule DC-DC converter with fast transient response, based on a linear-nonlinear control is presented. The proposed digital control improves the stability of the system, cuts off the effects of limit-cycle and reduces the recovery time, by making the "effective" bandwidth of the system independent of the bandwidth of the linear control loop and limits, at the same time, output voltage variations. The digital control is AVP-compatible and halves the recovery time. Preliminary hardware tests on a single phase step-down converter are reported. The experimental results match simulation ones, obtained by modelling system with Matlab/Aldec mixed environm…
Bidirectional high-power high-efficiency non-isolated step-up DC-DC converter
2006
This paper presents the results of a high-efficiency high-power (5kW) non-isolated bidirectional DC-DC converter. High efficiency, high stability and simplicity are the main goals, and no galvanic isolation is required. The proposed topology is a new BOOST converter with output filter where input and output inductors are coupled together which can be designed to be a minimum phase system. This topology provides therefore input and output current filtering, reducing noise and need of additional filters. Its bidirectionality reduces mass in many applications like in charge/discharge subsystems and lowers cost and component count. This converter is useful with any system that needs backup batt…
k-Space filtering in 2D gradient-echo breath-hold hyperpolarized3He MRI: Spatial resolution and signal-to-noise ratio considerations
2002
In this work some of the factors that can influence the signal-to-noise ratio (SNR) and spatial resolution in MR images of inhaled hyperpolarized gases are systematically addressed. In particular, the effects of RF depletion of longitudinal polarization and image gradient diffusion dephasing were assessed in terms of their contribution to a k-space filter. By means of theoretical simulations and a novel method of experimental validation using a variable transverse magnetization of the 1H signal, systematic quantitative and qualitative investigations of the effects of k-space filtering intrinsic to imaging of hyperpolarized gas were made. A 2D gradient-echo image is considered for a range of…
Exploiting EDCA for Feedback Channels in Hybrid VLC/WiFi Architectures
2021
In this paper, we consider integrating VLC and WiFi technologies in a scenario in which Light-Emitting-Diodes (LEDs), acting as network access points (APs) for ultra-dense Internet of Things applications, are deployed into an indoor lighting infrastructure. In such a scenario, RF-links can be exploited for complementing VLC-links in dealing with mobility and bidirectional communications, which can be problematic due to the limited coverage areas and self-generated interference of VLC APs. In particular, we consider the possibility of supporting a technology-based duplexing scheme, in which downlink and uplink transmissions are performed by means, respectively, of VLC and WiFi interfaces int…
Conjunction of Conditional Events and t-Norms
2019
We study the relationship between a notion of conjunction among conditional events, introduced in recent papers, and the notion of Frank t-norm. By examining different cases, in the setting of coherence, we show each time that the conjunction coincides with a suitable Frank t-norm. In particular, the conjunction may coincide with the Product t-norm, the Minimum t-norm, and Lukasiewicz t-norm. We show by a counterexample, that the prevision assessments obtained by Lukasiewicz t-norm may be not coherent. Then, we give some conditions of coherence when using Lukasiewicz t-norm
Sonority as a Phonological Cue in Early Perception of Written Syllables in French
2020
Many studies focused on the letter and sound co-occurrences to account for the well-documented syllable-based effects in French in visual (pseudo)word processing. Although these language-specific statistical properties are crucial, recent data suggest that studies that go all-in on phonological and orthographic regularities may be misguided in interpreting how—and why—readers locate syllable boundaries and segment clusters. Indeed, syllable-based effects could depend on more abstract, universal phonological constraints that rule and govern how letter and sound occur and co-occur, and readers could be sensitive to sonority—a universal phonological element—for processing (pseudo)words. Here, …
A Novel Approach to Propagation Pattern Analysis in Intracardiac Atrial Fibrillation Signals
2010
The purpose of this study is to investigate propagation patterns in intracardiac signals recorded during atrial fibrillation (AF) using an approach based on partial directed coherence (PDC), which evaluates directional coupling between multiple signals in the frequency domain. The PDC is evaluated at the dominant frequency of AF signals and tested for significance using a surrogate data procedure specifically designed to assess causality. For significantly coupled sites, the approach allows also to estimate the delay in propagation. The methods potential is illustrated with two simulation scenarios based on a detailed ionic model of the human atrial myocyte as well as with real data recordi…