456 research outputs found
Participatory Videos: A New Media for Promoting Organic Farming in Northern Bangladesh
Significance of agricultural extension to eliminate poverty, vulnerability, hunger and pollution is well-established in the perspective of developing countries. However, extension services in Bangladesh missed the opportunity to reduce poverty and pollution in a cost-effective way. This is due to lack of innovative ways to support farmer-to-farmer learning process. This paper presents the thoughts, empirical evidences and vision about approaches of video-mediated learning to enhance household food security and reducing pollution caused by agro-chemicals used in the field of agriculture. Following a model of participatory video (PV) supported women farmersâ capacity building process for preparation and use of botanical pesticide and vermin-compost in organic vegetables production. Findings of the study showed that PV has unexploited potentials to promote farmersâ innovation and adoption of organic farming by the farmers in the study area
Scenario of inflationary cosmology from the phenomenological models
Choosing the three phenomenological models of the dynamical cosmological term
, viz., , and
where is the cosmic scale factor, it has been shown by
the method of numerical analysis that the three models are equivalent for the
flat Universe . The evolution plots for dynamical cosmological term
vs. time and also the cosmic scale factor vs. are drawn
here for . A qualitative analysis has been made from the plots which
supports the idea of inflation and hence expanding Universe.Comment: 12 latex pages with 12 figures; Replaced with the revised version;
Accepeted for `J. Non-lin. Frac. Phen. Sci. Engg.
Recommended from our members
An experimental scale-model study of seismic response of an underground opening in jointed rock mass
This report describes an experimental investigation conducted by the Center for Nuclear Waste Regulatory Analyses (CNWRA) to (i) obtain a better understanding of the seismic response of an underground opening in a highly-fractured and jointed rock mass and (ii) generate a data set that can be used to evaluate the capabilities (analytical methods) to calculate such response. This report describes the design and implementation of simulated seismic experiments and results for a 1/15 scale model of a jointed rock mass with a circular tunnel in the middle. The discussion on the design of the scale model includes a description of the associated similitude theory, physical design rationale, model material development, preliminary analytical evaluation, instrumentation design and calibration, and model assembly and pretest procedures. The thrust of this discussion is intended to provide the information necessary to understand the experimental setup and to provide the background necessary to understand the experimental results. The discussion on the experimental procedures and results includes the seismic input test procedures, test runs, and measured excitation and response time histories. The closure of the tunnel due to various levels of seismic activity is presented. A threshold level of seismic input amplitude was required before significant rock mass motion occurred. The experiment, though designed as a two-dimensional representation of a rock mass, behaved in a somewhat three-dimensional manner, which will have an effect on subsequent analytical model comparison
Recommended from our members
Field site investigation: Effect of mine seismicity on groundwater hydrology
The results of a field investigation on the groundwater-hydrologic effect of mining-induced earthquakes are presented in this report. The investigation was conducted at the Lucky Friday Mine, a silver-lead-zinc mine in the Coeur d`Alene Mining District of Idaho. The groundwater pressure in sections of three fracture zones beneath the water table was monitored over a 24-mo period. The fracture zones were accessed through a 360-m-long inclined borehole, drilled from the 5,700 level station of the mine. The magnitude, source location, and associated ground motions of mining-induced seismic events were also monitored during the same period, using an existing seismic instrumentation network for the mine, augmented with additional instruments installed specifically for the project by the center for Nuclear Waste Regulatory Analyses (CNWRA). More than 50 seismic events of Richter magnitude 1.0 or larger occurred during the monitoring period. Several of these events caused the groundwater pressure to increase, whereas a few caused it to decrease. Generally, the groundwater pressure increased as the magnitude of seismic event increased; for an event of a given magnitude, the groundwater pressure increased by a smaller amount as the distance of the observation point from the source of the event increased. The data was examined using regression analysis. Based on these results, it is suggested that the effect of earthquakes on groundwater flow may be better understood through mechanistic modeling. The mechanical processes and material behavior that would need to be incorporated in such a model are examined. They include a description of the effect of stress change on the permeability and water storage capacity of a fracture rock mass; transient fluid flow; and the generation and transmission of seismic waves through the rock mass
Commercialization approach for Versatile Multi-Crop Planter: Lessons learnt
A Versatile Multi-crop Planter (VMP) was designed and built for seed and fertilizer application in lines when driven by 2-wheel tractors (2WT) for: single-pass shallow-tillage (SPST); strip planting (SP); zero tillage (ZT); bed planting (BP) and conventional tillage (CT). Land preparation cost by VMP was decreased by up to 75 % for single pass compared to CT (Haque at el., 2011). The VMP was capable of sowing many types of crop seeds from small jute seed up to maize seed. Demand for mechanized planters by smallholder farmers is growing rapidly due to the shortage of farm labour for operations such as planting or transplanting. Despite the promising seeder and planter developments, few of the present planters for 2WT are commercialized in Bangladesh. With the funding support from the Australian Centre for International Agricultural Research (ACIAR), the VMP commercialization activities commenced in 2012. Initially (2012 to 2014), the VMP commercialization activities were led by International Development Enterprises (IDE) and that approach was followed by a different approach implemented by the Project Implementation Office (PIO) of Murdoch University, Australia. In this paper, we will synthesis the VMP commercialization approaches and outcomes to identify key lessons learnt
Self-organising comprehensive handover strategy for multi-tier LTE-advanced heterogeneous networks
Long term evolution (LTE)-advanced was introduced as real fourth generation (4G) with its new features and additional functions, satisfying the growing demands of quality and network coverage for the network operators' subscribers. The term muti-tier has also been recently used with respect to the heterogeneity of the network by applying the various subnetwork cooperative systems and functionalities with self-organising capabilities. Using indoor short-range low-power cellular base stations, for example, femtocells, in cooperation with existing long-range macrocells are considered as the key technical challenge of this multi-tier configuration. Furthermore, shortage of network spectrum is a major concern for network operators which forces them to spend additional attentions to overcome the degradation in performance and quality of services in 4G HetNets. This study investigates handover between the different layers of a heterogeneous LTE-advanced system, as a critical attribute to plan the best way of interactive coordination within the network for the proposed HetNet. The proposed comprehensive handover algorithm takes multiple factors in both handover sensing and decision stages, based on signal power reception, resource availability and handover optimisation, as well as prioritisation among macro and femto stations, to obtain maximum signal quality while avoiding unnecessary handovers
COVID-19 Epidemic in Bangladesh among rural and urban residents: an online cross-sectional survey of knowledge, attitudes, and practices
As other nations around the world, Bangladesh is facing enormous challenges with the novel coronavirus (COVID-19) epidemic. To design a prevention and control strategy for this new infectious disease, it is essential to first understand peopleâs knowledge, attitudes, and practices (KAP) regarding COVID-19. This study sought to determine KAP among rural and urban residents as well as predictors of preventive practices associated with COVID-19 in Bangladesh. A social media-based (Facebook) cross-sectional survey was conducted to explore these variables among Bangladeshi adults. Of 1520 respondents who completed the questionnaire, low level of good or sufficient knowledge of COVID-19 (70.8%) and practices associated with COVID-19 (73.8%) were found. Despite the low level of knowledge and practices, respondentsâ attitude (78.9%) towards COVID-19 was relatively high. Results suggest that compared to urban, rural residents are at a particularly high risk of COVID-19 because they were found to have significantly lower knowledge (p = 0.001) and practice levels (p = 0.002) than were urban residents. Multivariable logistic regression analysis identified gender, education, knowledge of COVID-19 transmission, signs and symptoms, and sources of information as factors significantly associated with preventive practices against COVID-19. Further attention and effort should be directed toward increasing both knowledge and practices targeting the general population in Bangladesh, particularly the rural and less educated residents. Findings from this study provide baseline data that can be used to promote integrated awareness of and effective health education programs about COVID-19 prevention and control strategies in Bangladesh, and similar COVID-19 endemic countries
Drinking Water Salinity and Raised Blood Pressure: Evidence from a Cohort Study in Coastal Bangladesh.
BACKGROUND: Millions of coastal inhabitants in Southeast Asia have been experiencing increasing sodium concentrations in their drinking-water sources, likely partially due to climate change. High (dietary) sodium intake has convincingly been proven to increase risk of hypertension; it remains unknown, however, whether consumption of sodium in drinking water could have similar effects on health. OBJECTIVES: We present the results of a cohort study in which we assessed the effects of drinking-water sodium (DWS) on blood pressure (BP) in coastal populations in Bangladesh. METHODS: DWS, BP, and information on personal, lifestyle, and environmental factors were collected from 581 participants. We used generalized linear latent and mixed methods to model the effects of DWS on BP and assessed the associations between changes in DWS and BP when participants experienced changing sodium levels in water, switched from "conventional" ponds or tube wells to alternatives [managed aquifer recharge (MAR) and rainwater harvesting] that aimed to reduce sodium levels, or experienced a combination of these changes. RESULTS: DWS concentrations were highly associated with BP after adjustments for confounding factors. Furthermore, for each 100 mg/L reduction in sodium in drinking water, systolic/diastolic BP was lower on average by 0.95/0.57 mmHg, and odds of hypertension were lower by 14%. However, MAR did not consistently lower sodium levels. CONCLUSIONS: DWS is an important source of daily sodium intake in salinity-affected areas and is a risk factor for hypertension. Considering the likely increasing trend in coastal salinity, prompt action is required. Because MAR showed variable effects, alternative technologies for providing reliable, safe, low-sodium fresh water should be developed alongside improvements in MAR and evaluated in "real-life" salinity-affected settings. https://doi.org/10.1289/EHP659
Geometrothermodynamics of five dimensional black holes in Einstein-Gauss-Bonnet-theory
We investigate the thermodynamic properties of 5D static and spherically
symmetric black holes in (i) Einstein-Maxwell-Gauss-Bonnet theory, (ii)
Einstein-Maxwell-Gauss-Bonnet theory with negative cosmological constant, and
in (iii) Einstein-Yang-Mills-Gauss-Bonnet theory. To formulate the
thermodynamics of these black holes we use the Bekenstein-Hawking entropy
relation and, alternatively, a modified entropy formula which follows from the
first law of thermodynamics of black holes. The results of both approaches are
not equivalent. Using the formalism of geometrothermodynamics, we introduce in
the manifold of equilibrium states a Legendre invariant metric for each black
hole and for each thermodynamic approach, and show that the thermodynamic
curvature diverges at those points where the temperature vanishes and the heat
capacity diverges.Comment: New sections added, references adde
Human Health Risk Assessment For Arsenic: A Critical Review
Millions of people are exposed to arsenic resulting in a range of health implications.This paper provides an up-to-date review of the different sources of arsenic (water, soil and food), indicators of human exposure (biomarker assessment of hair, nail, urine and blood), epidemiological and toxicological studies on carcinogenic and non-carcinogenic health outcomes, and risk assessment approaches. The review demonstrates a need for more work evaluating the risks of different arsenic species such as; arsenate, arsenite monomethylarsonic acid, monomethylarsonous acid, dimethylarsinic acid and dimethylarsinous acid as well as a need to better integrate the different exposure sources in risk assessments
- âŚ