Development of smart controller model for dual fuel generator systems

Application of dual fuel powered electric generators such as one of diesel and biogas has gained popularity locally both as emergency power supply units and in distributed power systems. Dual fuel generators use two fuel types simultaneously in their operations. This is however faced with challenges in control and fuel regulation since their operation must be economically feasible and convenient. To achieve this, an intelligent controller that regulates generator operations is necessary. This research work, set to determine operation characteristic of these generators and fuel‐load relationship of the dual fuel engines in order to design a control system for a dual fuel power generator system. Generator characteristics such as fuel consumption on various loads were obtained through experiments; it was found that injection of biogas in diesel engine saves diesel consumption by approximately 30% on low load and 60% on high load. The presented model switches the generator when needed and adjusts biogas inlet in steps proportional to the load. It works by monitoring load, injecting a small volume of biogas for loads below 10% and increasing it as the load increases to maximum possible volume for load above 80%. The model was tested through simulation of the obtained data on a Siemens ™ micro Logic controller demonstrating a solution to control challenges. This model logic for control and offers advanced logic electronic control for local applications. It is essential in providing a versatile solution for a middle sized diesel biogas dual fuel power generator control

Adult population as potential reservoir of NTD infections in rural villages of Kwale district, Coastal Kenya: implications for preventive chemotherapy interventions policy

<p>Abstract</p> <p>Background</p> <p>Neglected tropical diseases (NTDs) are major public health problems in developing countries where they contribute to suffering of populations living in poor settings. As part of a research project started in September 2009 in Kwale district, Coast Region, Kenya, a baseline cross-sectional survey was conducted in 5 rural villages to provide information on the status of NTDs, including urinary schistosomiasis, soil-transmitted helminthiasis (STH), and lymphatic filariasis. This paper presents the results of a parasitological investigation among adults in the study villages.</p> <p>Methods</p> <p>A total of 599 adults in the 5 study villages were tested for NTD infections in urine, stool and blood. The presence of <it>Schistosoma haematobium </it>infection was determined by the urine filtration method. The presence of STH in stool was determined by Kato-Katz method while filarial antigenaemia was determined using immunochromatographic (ICT) test.</p> <p>Results</p> <p>The study revealed high prevalence of hookworm (41.7%) and schistosomiasis (18.2%) infections among adults in the study villages. Of the 599 individuals examined, 50.1% had one or more helminthic infections. There was low level of polyparasitism with helminthic NTDs in the study population with 9.5% and 1.7% of the participants having two and three infections, respectively.</p> <p>Conclusions</p> <p>In the current study, hookworm and schistosomiasis infections were identified as important infections among adults living in areas of high endemicity for these infections. Thus, if this section of the population is left untreated it may remain an important potential reservoir and a source of re-infection for school-age children treated in school deworming programmes. Therefore, there is a need to design novel strategies for preventive chemotherapy interventions that could allow inclusion of adults in an effort to reduce force of infection in high endemic communities.</p

Experts’ knowledge renewal and maintenance actions effectiveness in high-mix low-volume industries, using Bayesian approach

International audienceIncreasing demand diversity have resulted in high-mix low-volume production where success depends on our ability to quickly design and develop new products. This requires sustainable production capacities and efficient equipment utilization which is ensured through appropriate maintenance strategies. At present, these are derived from experts' knowledge, capitalized in FMECA (Failure Mode, Effect and Criticality Analysis) and/or maintenance procedures. (Abu-Samah et al. 2015) found increasing unscheduled breakdowns, failure durations and number of repair actions in each failure as the key challenges while sustaining production capacities in complex production environment. This is an evidence that maintenance based on the historical knowledge is not always effective to cope up with an evolving nature of equipment failure behaviors. Therefore, in this paper, we present an operational methodology based on Bayesian approach and an extended FMECA method to support experts' knowledge renewal and maintenance actions effectiveness. In the proposed methodology, we capitalize and model experts' existing knowledge from FMECA files as an operational Bayesian network (O-BN) to provide real time feedback on poorly executed maintenance actions. The accuracy of O-BN is monitored through drift in maintenance performance measurement (MPM) indicators that results in learning an unsupervised Bayesian network (U-BN) to discover new causal relations from historical data. The structural difference between O-BN and U-BN highlights potential new knowledge which is validated by experts prior to modify existing FMECA and associated maintenance procedures. The proposed methodology is evaluated in a well reputed high-mix low-volume semiconductor production line to demonstrate its ability to dynamically renew experts' knowledge and improve maintenance actions effectiveness

Integrated community-directed intervention for schistosomiasis and soil transmitted helminths in western Kenya – a pilot study

<p>Abstract</p> <p>Background</p> <p>Schistosome and soil-transmitted helminth (STH) infections are recognized as major global public health problems, causing severe and subtle morbidity, including significant educational and nutritional effects in children. Although effective and safe drugs are available, ensuring access to these drugs by all those at risk of schistosomiasis and STHs is still a challenge. Community-directed intervention (CDI) has been used successfully for mass distribution of drugs for other diseases such as onchocerciasis and lymphatic filariasis. A national control programme is yet to be instituted in Kenya and evidence for cost-effective strategies for reaching most affected communities is needed. This study evaluated the effectiveness and feasibility of the CDI strategy in the control of schistosomiasis and STHs, in East Uyoma location, Rarieda district, a community of western Kenya that is highly endemic for both infections.</p> <p>Results</p> <p>Pre-treatment prevalence of <it>S. mansoni</it> averaged 17.4% (range 5-43%) in the entire location. Treatment coverage in different villages ranged from 54.19 to 96.6% by community drug distributor (CDD) records. Assessment from a household survey showed coverage of 52.3 -91.9% while the proportion of homesteads (home compounds) covered ranged from 54.9-98.5%. Six months after one round of drug distribution, the prevalence levels of <it>S. mansoni,</it> hookworm and <it>Trichuris trichura</it> infections were reduced by 33.2%, 69.4% and 42.6% respectively.</p> <p>Conclusions</p> <p>This study shows that CDI is an accepted and effective strategy in the mass treatment of schistosomiasis and STH infections in resource constrained communities in Kenya and may be useful in similar communities elsewhere. A controlled trial comparing CDI and school based mass drug administration to demonstarte their relative advantages is ongoing.</p

Ecological determinants of pathogen infection in howler monkeys

Infectious diseases caused by pathogens are now recognized as one of the most important threats to primate conservation. The fact that howler monkeys (Alouatta spp.) are widely distributed from Southern Mexico to Northern Argentina, inhabit a diverse array of habitats, and are considered pioneers, particularly adapted to exploit marginal habitats, provides an opportunity to explore general trends of parasitism and evaluate the dynamics of infectious diseases in this genus. We take a meta-analysis approach to examine the effect of ecological and environmental variables on parasitic infection using data from 7 howler monkey species at more than 35 sites throughout their distribution. We found that different factors including precipitation, latitude, altitude, and human proximity may infl uence parasite infection depending on the parasite type. We also found that parasites infecting howler monkeys followed a right-skewed distribution, suggesting that only a few individuals harbor infections. This result highlights the importance of collecting large sample sizes when developing these kinds of studies. We suggest that future studies should focus on obtaining fi ne-grained measurements of ecological and microclimate changes to provide better insights into the proximate factors that promote parasitism.Fil: Martinez Mota, Rodolfo. University of Illinois at Urbana-Champaign; Estados UnidosFil: Kowalewski, Miguel Martin. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia". Estación Biológica de Usos Múltiples (Sede Corrientes); ArgentinaFil: Gillespie, Thomas R.. Emory University; Estados Unido