57 research outputs found
Design procedures of reinforced concrete framed buildings in Nepal and its impact on seismic safety
The present paper analyses the design procedure and its impact on seismic
safety of the structures. For this, a representative reinforced concrete frame building
(WDS) is designed and the results are compared with similar buildings detailed with:
i) Current Construction Practices (CCP); ii) the Nepal Building Code (NBC) and iii)
the Modified Nepal Building Code (NBC+) recommendations. The seismic
performance evaluation is done with global strength, inter-storey drift and
displacement of the structures. Likewise, the sensitivity of the structural and
geometrical parameters of the RC frame building is studied through nonlinear analysis.
The study parameters considered for parametric analysis are column size, beam size,
inter-storey height, bay length, bay width, and compressive strength of concrete. The
results show that the influence on the structural behaviour, particularly by variation in
column size and inter-storey height. Additionally, the influence of the seismic zone
factor on reinforcement demand of the structure is studied. The result shows that
structures designed for high to medium seismic hazard demands double the
reinforcement in beams compared to structures in low seismic zone
Knowledge Priorities on Climate Change and Water in the Upper Indus Basin: A Horizon Scanning Exercise to Identify the Top 100 Research Questions in Social and Natural Sciences
River systems originating from the Upper Indus Basin (UIB) are dominated by runoff from snow and glacier melt and summer monsoonal rainfall. These water resources are highly stressed as huge populations of people living in this region depend on them, including for agriculture, domestic use, and energy production. Projections suggest that the UIB region will be affected by considerable (yet poorly quantified) changes to the seasonality and composition of runoff in the future, which are likely to have considerable impacts on these supplies. Given how directly and indirectly communities and ecosystems are dependent on these resources and the growing pressure on them due to ever-increasing demands, the impacts of climate change pose considerable adaptation challenges. The strong linkages between hydroclimate, cryosphere, water resources, and human activities within the UIB suggest that a multi- and inter-disciplinary research approach integrating the social and natural/environmental sciences is critical for successful adaptation to ongoing and future hydrological and climate change. Here we use a horizon scanning technique to identify the Top 100 questions related to the most pressing knowledge gaps and research priorities in social and natural sciences on climate change and water in the UIB. These questions are on the margins of current thinking and investigation and are clustered into 14 themes, covering three overarching topics of ‘governance, policy, and sustainable solutions’, ‘socioeconomic processes and livelihoods’, and ‘integrated Earth System processes’. Raising awareness of these cutting-edge knowledge gaps and opportunities will hopefully encourage researchers, funding bodies, practitioners, and policy makers to address them
A Review of the Common Neurodegenerative Disorders: Current Therapeutic Approaches and the Potential Role of Nanotherapeutics
Neurodegenerative disorders are primarily characterized by neuron loss. The most common neurodegenerative disorders include Alzheimer’s and Parkinson’s disease. Although there are several medicines currently approved for managing neurodegenerative disorders, a large majority of them only help with associated symptoms. This lack of pathogenesis-targeting therapies is primarily due to the restrictive effects of the blood–brain barrier (BBB), which keeps close to 99% of all “foreign substances” out of the brain. Since their discovery, nanoparticles have been successfully used for targeted delivery into many organs, including the brain. This review briefly describes the pathophysiology of Alzheimer’s, Parkinson’s disease, and amyotrophic lateral sclerosis, and their current management approaches. We then highlight the major challenges of brain-drug delivery, followed by the role of nanotherapeutics for the diagnosis and treatment of various neurological disorders
Response reduction factor of irregular RC buildings in Kathmandu valley
Most current seismic design includes the nonlinear response of a structure through a response reduction
factor (R). This allows the designer to use a linear elastic force-based approach while accounting for nonlinear behavior and
deformation limits. In fact, the response reduction factor is used in modern seismic codes to scale down the elastic response
of a structure. This study focuses on estimating the actual ‘R’ value for engineered design/construction of reinforced concrete
(RC) buildings in Kathmandu valley. The ductility and overstrength of representative RC buildings in Kathmandu are
investigated. Nonlinear pushover analysis was performed on structural models in order to evaluate the seismic performance
of buildings. Twelve representative engineered irregular buildings with a variety of characteristics located in the Kathmandu
valley were selected and studied. Furthermore, the effects of overstrength on the ductility factor, beam column capacity ratio
on the building ductility, and load path on the response reduction factor, are examined. Finally, the results are further analyzed
and compared with different structural parameters of the buildings
Critical Components for XUV Probing of Laser Driven Shocks
International audienceRadiative shocks can be produced in gases using high-energy lasers. As the electron density may be higher than the critical density for visible light, radiography with soft x-ray radiation becomes very promising technique to probe these shocks. Feasibility of this method has been proven employing zinc soft x-ray laser at 21.2 nm as backlighter. The experiment has shown high requirements on quality of the imaging optics and windows of the gas filled cell
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