4,060 research outputs found
Ultrasonic, molecular and mechanical testing diagnostics in natural fibre reinforced, polymer-stabilised earth blocks
The aim of this research study was to evaluate the influence of utilising natural polymers as a form of soil stabilization, in order to assess their potential for use in building applications. Mixtures were stabilized with a natural polymer (alginate) and reinforced with wool fibres in order to improve the overall compressive and flexural strength of a series of composite materials. Ultrasonic pulse velocity (UPV) and mechanical strength testing techniques were then used to measure the porous properties of the manufactured natural polymer-soil composites, which were formed into earth blocks. Mechanical tests were carried out for three different clays which showed that the polymer increased the mechanical resistance of the samples to varying degrees, depending on the plasticity index of each soil. Variation in soil grain size distributions and Atterberg limits were assessed and chemical compositions were studied and compared. X-ray diffraction (XRD), X-ray fluorescence spectroscopy (XRF), and energy dispersive X-ray fluorescence (EDXRF) techniques were all used in conjunction with qualitative identification of the aggregates. Ultrasonic wave propagation was found to be a useful technique for assisting in the determination of soil shrinkage characteristics and fibre-soil adherence capacity and UPV results correlated well with the measured mechanical properties
A combination of SEM and EDX studies on a clay-based natural composite with animal fibre and its mechanical implications
A variety of natural fibres are nowadays being utilized as soil reinforcement. Test results demonstrate the positive effects of adding natural fibres to soils, in that they decrease shrinkage, reduce curing time and enhance compressive, flexural and shear strength if an optimum reinforcement ratio can be utilised. This paper describes a study which uses a Scanning Electron Microscope (SEM) and an Energy Diffraction Analysis of X-rays (EDX) technique on clay-based composites stabilized with natural polymer and fibres. Different dosages of fibres and several types of soils have been used in this study with the aim of determining advantageous properties for building material applications. SEM and EDX test results reveal the degree of bonding between the particles of soil and the natural fibers. This has enabled a better understanding of the micro-morphology of the natural fibers and their effect on the overall composite material structure. Microscopic analysis was combined with mechanical tests to establish the different strength characteristics of every soil
Ultrasonic, molecular and mechanical testing diagnostics in natural fibre reinforced, polymer-stabilised earth blocks
The aim of this research study was to evaluate the influence of utilising natural polymers as a form of soil stabilization, in order to assess their potential for use in building applications. Mixtures were stabilized with a natural polymer (alginate) and reinforced with wool fibres in order to improve the overall compressive and flexural strength of a series of composite materials. Ultrasonic pulse velocity (UPV) and mechanical strength testing techniques were then used to measure the porous properties of the manufactured natural polymer-soil composites, which were formed into earth blocks. Mechanical tests were carried out for three different clays which showed that the polymer increased the mechanical resistance of the samples to varying degrees, depending on the plasticity index of each soil. Variation in soil grain size distributions and Atterberg limits were assessed and chemical compositions were studied and compared. X-ray diffraction (XRD), X-ray fluorescence spectroscopy (XRF), and energy dispersive X-ray fluorescence (EDXRF) techniques were all used in conjunction with qualitative identification of the aggregates. Ultrasonic wave propagation was found to be a useful technique for assisting in the determination of soil shrinkage characteristics and fibre-soil adherence capacity and UPV results correlated well with the measured mechanical properties
Dementia Knowledge Among Hispanic Family Caregivers
The Health Projects Center (HPC) was established in 1980 as a non-profit corporation serving Monterey, Santa Cruz, and San Benito Counties. HPC offers programs to health and social service professionals, older adults, and family caregivers. At HPC many caregivers experience health problems associated with caregiving distress. To address this concern, “Dementia Knowledge Among Hispanic Caregivers” was implemented, to determine the effectiveness of the Caregiver Support Group at HPC. This group consisted of caregivers of Mexican descent, whose primary language is Spanish, who are caring for a loved one who suffers from dementia or a cognitive disorder. In order to assess caregivers’ knowledge of dementia and stress, a questionnaire was used. The expected outcome was for all participants to recognize the symptoms of dementia and to recognize when they are under stress. The questions were read aloud for the participants to ensure there were no language barriers. The findings were that 66.67% recognize symptoms of Alzheimer’s and even though, 83.33% recognized when they were under stress, only 50% practiced self-care. There are three recommendations for the agency, including implementing a session in the support group that focuses more on enhancing the caregiver’s knowledge on different stages of dementia. Additionally, it is recommended to have two groups, one for experienced caregivers and the other for new caregivers. Finally, all caregivers could use more support on how to actually practice self-care
Distribución y uso tradicional de Sagittaria macrophylla Zucc. y S. latifolia Willd. en el Estado de México
Sagittaria macrophylla y S. latifolia son plantas acuáticas emergentes que crecen en las orillas y zonas poco profundas de los cuerpos de agua limpios y de poca corriente. La primera es endémica de México, su distribución se restringe a la región del río Lerma y valle de México y está en peligro de extinción. Sagittarial latifolia se distribuye desde Canadá hasta el noroeste de Sudamérica. En México se localiza al menos en 11 estados. El análisis de la distribución de ambas especies muestra una disminución en el Estado de México; los factores que aparentemente están contribuyendo a este fenómeno son, en general, la explosión demográfica, la pérdida del hábitat y la sobreexplotación. No había registros del uso de S. latifolia en México, actualmente se reconoce que sus tubérculos o 'papas de agua' tienen importancia económica en la región del río Lerma. El uso tradicional de ambas especies indica que podrían ser una alternativa más en la dieta humana y animal.Sagittaria macrophylla y S. latifolia son plantas acuáticas emergentes que crecen en las orillas y zonas poco profundas de los cuerpos de agua limpios y de poca corriente. La primera es endémica de México, su distribución se restringe a la región del río Lerma y valle de México y está en peligro de extinción. Sagittarial latifolia se distribuye desde Canadá hasta el noroeste de Sudamérica. En México se localiza al menos en 11 estados. El análisis de la distribución de ambas especies muestra una disminución en el Estado de México; los factores que aparentemente están contribuyendo a este fenómeno son, en general, la explosión demográfica, la pérdida del hábitat y la sobreexplotación. No había registros del uso de S. latifolia en México, actualmente se reconoce que sus tubérculos o ‘papas de agua’ tienen importancia económica en la región del río Lerma. El uso tradicional de ambas especies indica que podrían ser una alternativa más en la dieta humana y animal
Herbolaria y pintura mural: plantas medicinales en los murales del convento del Divino Salvador de Malinalco, Estado de México
En la época prehispánica Malinalco fue un centro ceremonial importante, probablemente de control ideológico y económico. Para reforzar el proceso de evangelización después de la conquista, se fundó en 1540 el convento agustino de San Cristóbal ahora conocido como del Divino Salvador. Poco después de su edifi cación, sus paredes y bóvedas fueron decoradas por artistas nativos con pasajes bíblicos, exuberantes plantas y diferentes especies de animales. Los análisis que se han realizado de estos murales indican que todos los elementos naturales ilustrados en ellos tenían un signifi cado específi co para la antigua cultura mexicana. Con la intención de conocer las especies de plantas representadas en los frescos, los usos medicinales que tenían en la época en la que fueron pintados y la posible continuidad de su uso hasta la actualidad, se realizaron comparaciones de las plantas de los frescos con la fl ora actual y con las plantas ilustradas en diferentes códices. Se revisaron sus usos prehispánicos y actuales, así como su distribución. Se reconocieron 31 especies diferentes de plantas medicinales en los frescos. Estas plantas pertenecen a 25 familias, 21 plantas se determinaron a nivel específi co y 10 se reportan como especies afi nes. El 90.4% de las plantas identifi cadas en los murales tienen una distribución natural en el continente americano, de éstas, el 42% son exclusivas de México. De las plantas identificadas, el 90% se registran útiles en la época prehispánica y sólo el 77.4% se usan actualmente, lo cual puede indicar una pérdida del uso de algunas plantas, entre ellas las que también eran utilizadas en la época prehispánica como mágico-religiosas. Sin embargo, se observa un enriquecimiento de la cultura de uso de las plantas con la incorporación de especies introducidas con la conquista como la uva (Vitis vinifera) y la rosa (Rosa aff. canina) y por el uso de una planta para el tratamiento de uno o varios padecimientos o el empleo de varias plantas para un mismo padecimiento. Las categorías de uso más frecuente tanto en la época prehispánica como en la actual, son las relacionadas con enfermedades gastrointestinales, dermatológicas y con síntomas y estados morbosos mal defi nidos
FISCAL POLICY AND LONG-TERM ECONOMIC GROWTH: LESSONS FROM THE EURO AREA
At the beginning of 2020, the European Union embarked on a process of reviewing its macroeconomic policy strategy and economic governance framework. While the review of the monetary policy framework was approved in July 2021, the review of the fiscal policy framework was put on hold as a result of the outbreak of the covid-19 pandemic and the ensuing economic crisis. The Covid-19 crisis led to a breach of fiscal rules in the European Union and an unprecedented increase in the size of fiscal imbalances. In this context, there is a need for a radical reform of the fiscal rules still in force to allow for a more active role of national fiscal policies and to avoid the serious economic problems resulting from the fiscal austerity policies emanating from the Maastricht Treaty, the Stability and Growth Pact and the successive reforms of the latter.At the beginning of 2020, the European Union embarked on a process of reviewing its macroeconomic policy strategy and economic governance framework. While the review of the monetary policy framework was approved in July 2021, the review of the fiscal policy framework was put on hold as a result of the outbreak of the covid-19 pandemic and the ensuing economic crisis. The Covid-19 crisis led to a breach of fiscal rules in the European Union and an unprecedented increase in the size of fiscal imbalances. In this context, there is a need for a radical reform of the fiscal rules still in force to allow for a more active role of national fiscal policies and to avoid the serious economic problems resulting from the fiscal austerity policies emanating from the Maastricht Treaty, the Stability and Growth Pact and the successive reforms of the latter
Information System for Environmental Technologies
Geographical Information Systems (GIS) play an important role in environmental management solutions, and they are being used with increasing frequency in environmental studies. The use of GIS technology in environmental studies provides a better way to manage, analyze, display and share the information. In this thesis, I automated a process for constructing GIS maps of odor complaints and inspections that have been used to study odor complaints in the vicinity of three landfills in Jefferson Parish. I provided an application that integrates daily environmental observation and monitoring data into a GIS and publishes the resulting maps through the Internet. The user\u27s interaction with the web-based maps does not require any GIS expertise. A Webapplication was also implemented for managing the list of the constructed maps. The maps are deleted or updated through the manager application, a friendly interface application that does not require users to have any GIS technology knowledge
Analytical Modeling of Interference Aware Power Control for the Uplink of Heterogeneous Cellular Networks
Inter-cell interference is one of the main limiting factors in current
Heterogeneous Cellular Networks (HCNs). Uplink Fractional Power Control (FPC)
is a well known method that aims to cope with such limiting factor as well as
to save battery live. In order to do that, the path losses associated with
Mobile Terminal (MT) transmissions are partially compensated so that a lower
interference is leaked towards neighboring cells. Classical FPC techniques only
consider a set of parameters that depends on the own MT transmission, like
desired received power at the Base Station (BS) or the path loss between the MT
and its serving BS, among others. Contrary to classical FPC, in this paper we
use stochastic geometry to analyze a power control mechanism that keeps the
interference generated by each MT under a given threshold. We also consider a
maximum transmitted power and a partial compensation of the path loss.
Interestingly, our analysis reveals that such Interference Aware (IA) method
can reduce the average power consumption and increase the average spectral
efficiency. Additionally, the variance of the interference is reduced, thus
improving the performance of Adaptive Modulation and Coding (AMC) since the
interference can be better estimated at the MT.Comment: 13 pages, 1 table and 7 figures. This work has been submitted to the
IEEE for possible publication. Copyright may be transferred without notice,
after which this version may no longer be accessibl
Ammonia observations of the nearby molecular cloud MBM 12
We present NH3(1,1) and NH3(2,2) observations of MBM 12, the closest known
molecular cloud (65 pc distance), aimed to find evidence for on-going star
formation processes. No local temperature (with a T_rot upper limit of 12 K)
nor linewidth enhancement is found, which suggests that the area of the cloud
we mapped (~ 15' size) is not currently forming stars. Therefore, this close
``starless'' molecular gas region is an ideal laboratory to study the physical
conditions preceding new star formation.
A radio continuum source was found in Very Large Array archive data, close
but outside the NH3 emission. This source is likely to be a background object.Comment: 8 pages, 3 figures, accepted by MNRA
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