A non-separable stochastic model for pulse-like ground motions

A phenomenological non-separable non-stationary stochastic model is proposed to represent near-fault pulse-like ground motions (PLGMs) by means of a parametrically defined evolutionary power spectrum (EPSD). Numerical data pertaining to ensembles of EPSD compatible realizations and considering statistical analysis of peak elastic and inelastic spectral ordinates demonstrate the applicability of the model to capture the salient effects of PLGMs to structural responses. To this aim, the model parameters are calibrated against a field recorded PLGM. Further numerical data considering stochastic processes compatible with the response spectrum of the European aseismic code (EC8) are furnished to demonstrate the potential of the proposed model for including near-fault effects to spectrum compatible representations of the seismic action. It is foreseen that this model can be a useful tool in accounting for the low-frequency content of PLGMs in both Monte Carlo simulation-based analyses and in statistical linearization based studies

Assessment of access to health services and vulnerabilities of female fish traders in the Kafue Flats, Zambia: analysis report

Under the regional programme Fisheries and HIV/AIDS in Africa: Investing in Sustainable Solutions, the WorldFish Center conducted this study on access to health services and vulnerabilities of female fish traders in the Kafue Flats floodplains in Zambia. This report outlines and analyses the particular vulnerabilities of female fish traders in the Kafue Flats fishery and formulates recommendations to facilitate stakeholder uptake of strategic responses to tackle the drivers of the epidemic in fishing communities and improve the livelihoods of fisher folk and fish traders in the Kafue Flats and other fisheries in Zambia.Women, Fishermen, Trade, Vulnerability, Viral diseases, Zambia,

Assessment of access to health services and vulnerabilities of female fish traders in the Kafue Flats, Zambia: analysis report

Under the regional programme Fisheries and HIV/AIDS in Africa: Investing in Sustainable Solutions, the WorldFish Center conducted this study on access to health services and vulnerabilities of female fish traders in the Kafue Flats floodplains in Zambia. This report outlines and analyses the particular vulnerabilities of female fish traders in the Kafue Flats fishery and formulates recommendations to facilitate stakeholder uptake of strategic responses to tackle the drivers of the epidemic in fishing communities and improve the livelihoods of fisher folk and fish traders in the Kafue Flats and other fisheries in Zambia. (pdf contains 55 pages

No interactions for a collection of Weyl gravitons intermediated by a scalar field

The cross-couplings among several Weyl gravitons (described in the free limit by a sum of linearized Weyl actions) in the presence of a scalar field are studied with the help of the deformation theory based on local BRST cohomology. Under the hypotheses of locality, smoothness of the interactions in the coupling constant, Poincare invariance, (background) Lorentz invariance, and the preservation of the number of derivatives on each field, together with the supplementary assumption that the internal metric defined by the sum of Weyl lagrangians is positively defined, we prove that there are no consistent cross-interactions among different Weyl gravitons in the presence of a scalar field. The couplings of a single Weyl graviton to a scalar field are also discussed.Comment: 53 page

Field study: assessing migration and mobility patterns, access to health services and vulnerabilities of female fish traders in the Kafue Flats fishery, Zambia: research design report

The WorldFish Center in Lusaka is implementing a regional collaborative programme entitled "Fisheries and HIV&AIDS in Africa; investing in sustainable solutions". The programme is funded by the Swedish International Development Cooperation Agency (Sida) and the Norwegian Ministry of Foreign Affairs. Under the Zambia component, the technical focus area "Options for reducing vulnerability along the fish marketing chain" focuses on the Kafue Flats fishery in Zambia. This study aims to identify vulnerability factors affecting fisher folk and fish traders in the Kafue Flats, especially those that make them susceptible and vulnerable to HIV&AIDS. The study will provide the analytical basis for pilot interventions to reduce specific vulnerability factors and enhance livelihoods for fisher folk and fish traders in the Kafue Flats fishery. This report describes the methodologies and approaches used for the study in the Kafue Flats fishery, and how the findings and analyses will be used for the further implementation and learning of the programme.Fisheries, AIDS, Public health, HIV, Nutritive value

Assessment of wavelet-based representation techniques for the characterization of stochastic processes modelling pulse-like strong ground motions

Recently, the Meyer wavelet packets transform (MWPT), the harmonic wavelet transform (HWT), and the S-transform have been used to process recorded earthquake induced strong ground motions (GMs) in various earthquake engineering and engineering seismology applications. In this paper, the potential of these three wavelet-based time-frequency representation (TFR) techniques to identify and to characterize low-frequency pulse-like content in GMs is assessed. This is achieved by processing ensembles of simulated non-stationary time-histories with known energy content upon appropriately fine-tuning the considered TFRs. Next, the ensemble average wavelet transform is used to characterize the energy distribution of the time-histories on the time-frequency plane, within a Monte-Carlo analysis framework. Specifically, the considered time-histories are realizations of sums of uncorrelated uniformly modulated stochastic processes characterized by analytically known evolutionary power spectra (EPSDs). These EPSDs are judicially defined to model the frequency content of pulse-like GMs. Pertinent numerical results considering EPSDs compatible with the elastic design spectrum of the current European (EC8) aseismic code provisions are included, in which pre-specified pulse-type frequency content is introduced by adding low-frequency "patches of energy". The reported numerical data indicate that the HWT provides for smoother estimates of the considered EPSDs than the MWPT. Further, the S-transform is more accurate than both the HWT and the MWPT in identifying the time location and central frequency of the low frequency components contained in the considered artificial pulse-like accelerograms. Overall, this study sheds light into the challenges of detecting low frequency content “corrupted” by higher frequency components in artificial signals modelling pulse-like accelerograms in an effort to inform best practices in the application of TFR techniques to characterize low frequency pulses in recorded GMs

Identification of temperature profile and heat transfer on a dielectric membrane for gas sensors by `COSMOS' program simulation

The application of commercial 3-D software `COSMOS' for the design and thermal analysis of the low power consumption test structures with dielectric membrane for gas microsensors is presented. Within this work, the simulation provides the estimation of the temperature profile on the active area and the whole membrane including the four bridges and the heating efficiency in the temperature range 20-500 °C. Unravelling of the heat loss mechanisms in terms of radiation, convection, conduction by air and solid materials during heat transfer on the dielectric membrane is reported for the first time as a mean to evaluate by 3-D simulation the contribution of technological processes and lay-out design to the total heat losses

Flames recognition for opinion mining

The emerging world-wide e-society creates new ways of interaction between people with different cultures and backgrounds. Communication systems as forums, blogs, and comments are easily accessible to end users. In this context, user generated content management revealed to be a difficult but necessary task. Studying and interpreting user generated data/text available on the Internet is a complex and time consuming task for any human analyst. This study proposes an interdisciplinary approach to modelling the flaming phenomena (hot, aggressive discussions) in online Italian forums. The model is based on the analysis of psycho/cognitive/linguistic interaction modalities among web communities' participants, state-of-the art machine learning techniques and natural language processing technology. Virtual communities' administrators, moderators and users could benefit directly from this research. A further positive outcome of this research is the opportunity to better understand and model the dynamics of web forums as the base for developing opinion mining applications focused on commercial applications

Is transcription of data on antiretroviral treatment from electronic to paper-based registers reliable in Malawi?

SETTING: Antiretroviral treatment (ART) clinics at one central hospital, three district hospitals and one mission hospital in the central and southern regions of Malawi. OBJECTIVE: To measure the extent of inaccuracies in the transcription of case registration and recorded deaths between electronic medical data (EMR) and paper registers. This was done to inform the Ministry of Health on the reliability of the paper-based system as backup in case of EMR failure. DESIGN: Retrospective analysis of routine programme data. RESULTS: A total of 31 763 registrations and 2922 deaths in the EMR were compared with those in the paper registers. In one hospital, up to 24% of overall case registrations were missing from the paper registers. At other sites, the differences were minor and included duplicate patients who should have been classified as ‘transfer in’ patients in the paper register. There were major differences in the number of registered deaths in two of the five facilities. CONCLUSION: There are varying degrees of agreement between the EMR and paper registers which compromise the use of the latter as a backup solution in case of EMR failure. The reasons for this unreliability and ways forward to address the problem are discussed