379 research outputs found
Application of Tuned Liquid Damper for Controlling Structural Vibration
Current trends in construction industry demands taller and lighter structures, which are also more flexible and having quite low damping value. This increases failure possibilities and also, problems from serviceability point of view. Several techniques are available today to minimize the vibration of the structure, out of which concept of using of TLD is a newer one. This study was made to study the effectiveness of using TLD for controlling vibration of structure. A numerical algorithm was developed to investigate the response of the frame model, fitted with a TLD. A linear TLD model was considered. A total of six loading conditions were applied at the base of the structure. First one was a sinusoidal loading corresponding to the resonance condition with the fundamental frequency of the structure, second one was corresponding to compatible time history as per spectra of IS-1894 (Part -1):2002 for 5% damping at rocky soil and rest four were corresponding to time histories of past earthquake such as 1940 El Centro Earthquake record (PGA = 0.313g), 1994 North Ridge Loading (PGA = 1.78g), 1971 Sanfernando Earthquake (PGA = 1.23g), 1989 Loma Prieta Earthquake (PGA = 0.59g). A ten storey and two bay structure was considered for the study. The effectiveness of the TLD was calculated in terms of amplitude of displacements at top storey of the structure.
From the study it was found that, TLD can effectively used to control the vibration of the structure. TLD was more effective when it is placed at the top storey of the structure. Only TLD which were properly tuned to natural frequency of structure was more effective in controlling the vibration. The damping effect of TLD is sharply decreases with mistuning of TLD
Participatory Statistics to Measure Prevalence in Bonded Labour Hotspots in Uttar Pradesh and Bihar: Report of Preliminary Findings of the Baseline Study
The Institute of Development Studies has been carrying out a programme of research, learning and evaluation in relation to the Freedom Fund ‘hotspot’ in northern India, a project that seeks to reduce bonded labour in the states of Uttar Pradesh and Bihar.
The work for this baseline study builds upon scoping visits comprising interviews with NGOs, focus groups with community members, field observations, the participatory collection and analysis of 353 life stories to identify the most significant indicators of change, and the generation of a baseline of participatory statistics of 3466 households across 82 hamlets in locations covered by 14 NGOs. This will be followed by the rollout of a systemic action research programme which combines stakeholders analysing and developing solutions to their problems with follow-up participatory statistical analysis. We will conduct an end-line survey two years after the data collection for this study has been completed.
The aim of the study was to estimate the prevalence of bonded labour in the selected intervention communities of the Freedom Fund hotspot in northern India. Prevalence data help mainly to understand the profile of families in bonded labour and any correlations with different variables. The analysis of life stories provided a better insight into the life situations of families in bonded labour and explored questions of why and how. With clear causal factors emerging from the life story analysis, the current prevalence study was able to focus on these important indicators. The team facilitated a discussion on the results at the end of the data collection process in each site. These discussions focused on the reasons for the differences in prevalence results using the tallied-up data to explore how gender, age and caste dynamics shape bonded labour, with most adults in bonded labour working inside the village; most boys in bondage working outside the village; and a group of families with all members in bonded labour working outside the village.Freedom Fun
Using Participatory Statistics to Examine the Impact of Interventions to Eradicate Slavery: Lessons from the Field
This CDI Practice Paper by Pauline Oosterhoff, Sowmyaa Bharadwaj, Danny Burns, Aruna Mohan Raj, Rituu B. Nanda and Pradeep Narayanan reflects on the use of participatory statistics to assess the impact of interventions to eradicate slavery and bonded labour. It deals with: (1) the challenges of estimating changes in the magnitude of various forms of slavery; (2) the potential of combining participatory approaches with statistical principles to generate robust data for assessing impact of slavery eradication; and (3) the practical and ethical questions in relation to working with people living within a context of modern slavery. The paper draws lessons from the realities of using participatory statistics to support the evaluation of a slavery eradication programme in North India.UK Department for International Developmen
Structural Damage Detection Based on Modal Parameters Using Continuous Ant Colony Optimization
A method is presented to detect and quantify structural damages from changes in modal parameters (such as natural frequencies and mode shapes). An inverse problem is formulated to minimize the objective function, defined in terms of discrepancy between the vibration data identified by modal testing and those computed from analytical model, which then solved to locate and assess the structural damage using continuous ant colony optimization algorithm. The damage is formulated as stiffness reduction factor. The study indicates potentiality of the developed code to solve a wide range of inverse identification problems
Sustainable Fly Ash Based Geopolymer Binders: A Review on Compressive Strength and Microstructure Properties
As a result of global warming, the pursuance of low-carbon, sustainable building materials has been prioritized. The development of geopolymer/cement-less binders can be considered an innovative and green way forward to minimize carbon footprint and tackle industrial waste material utilization. However, the chemical composition and properties of industrial waste-derived geopolymer binders varies considerably based on the chemical compositions of the source materials. This review paper presents a comprehensive understanding of the role of different chemical compositions (namely SiO2, Al2O3, CaO, Fe2O, and MgO) available in contemporary industrial wastes and the development of geopolymer binders. Subsequently, the compressive and microstructure properties of various FA-based geopolymer binders have been discussed to exhibit the feasibility of FA as a reliable source material. Significant findings and research gaps have been considered to aid future research works. Indeed, they provide guidelines for the commercial implementation of FA-based geopolymer binders as a low-carbon alternative to Portland cement
IOT based advanced medicine dispenser integrated with an interactive web application
Internet of Things (IOT) is a development of the internet which plays a major role in integrating human-machine interaction by allowing everyday objects to send and receive data in a variety of applications. Using IOT in healthcare monitoring provides an avenue for doctors and patients to interact and to track the dosage of medication administered. The paper presents an interactive, user friendly network integrated with an automated medicine dispenser which uses IOT, cloud computing and machine learning. The network was built on a python tornado framework with a front end developed using materialise CSS. The feasibility of this approach was validated by building a prototype and conducting a survey.Intelligent Electrical Power Grid
The role of graphene and its derivatives in modifying different phases of geopolymer composites: A review
There is broad agreement among researchers that the next facing of the construction material industry is ‘geopolymer composites’, also called ‘green composites. Although geopolymer composites have been extensively investigated as a new sustainable building material in recent years, their acceptability is still limited owing to few critical fragilities as a commercial material for construction. However, recent progress on geopolymer composites by several scientists suggests that it could be designed at the nanoscale to significantly enhance the chemical and physiomechanical characteristics to overcome multiple limitations. Graphene, a 2D nanomaterial, has been reported to improve various crucial properties when combined with geopolymer composites. This review paper starts with a bibliometric investigation of the studies related to graphene reinforced geopolymer composites (GRGC) to provide useful insights into current research trends. The paper described the synthesis of suitable graphene derivatives and the manufacturing of different phases of GRGC, namely ink, paste, mortar, and composites. Then a critical review is provided on the mechanical and electrical properties enhancement of graphene geopolymer matrix systems through the modification of the composite matrix at the nano-micro structural level. The GRGC has the potential to be used in multiple applications, such as the recycling of industrial solid waste, and is addressed in this paper. Research gaps were identified in the areas of suitable forms of graphene materials synthesis, dispersion, geopolymer binder type, mixing design, microstructure, and acceptance as well as implementation. The review clarifies those challenging aspects and presents guided solutions for developing sustainable, resilient, and efficient geopolymer matrix-based future materials
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