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Ramachandra T.V.,Indian Institute of Science | Ramachandra T.V.,Center for Infrastructure
Renewable and Sustainable Energy Reviews | Year: 2010

Rural population of India constitutes about 70% of the total population and traditional fuels account for 75% of the rural energy needs. Depletion of woodlands coupled with the persistent dependency on fuel wood has posed a serious problem for household energy provision in many parts. This study highlights that the traditional fuels still meet 85-95% of fuel needs in rural areas of Kolar district; people prefer fuel wood for cooking and agriculture residues for water heating and other purposes. However, rapid changes in land cover and land use in recent times have affected these traditional fuels availability necessitating inventorying, mapping and monitoring of bioresources for sustainable management of bioresources. Remote sensing data (Multispectal and Panchromatic), Geographic Information System (GIS), field surveys and non-destructive sampling were used to assess spatially the availability and demand of energy. Field surveys indicate that rural household depends on species such as Prosopis juliflora, Acacia nilotica, Acacia auriculiformis to meet fuel wood requirement for domestic activities. Hence, to take stock of fuel wood availability, mapping was done at species level (with 88% accuracy) considering villages as sampling units using fused multispectral and panchromatic data. © 2009 Elsevier Ltd. All rights reserved.

De Boer A.,Center for Infrastructure | Van Der Veen C.,Technical University of Delft
fib Symposium 2012: Concrete Structures for Sustainable Community - Proceedings | Year: 2012

Cantilever bridges, constructed in the Netherlands, are mostly designed for the main river crossings. A lot of them are constructed in the period of 1960-1975. Material time dependency modelling was rather time consuming and computer simulations of these phenomena were poor available yet. The longterm behaviour of these bridges was simulated in those days in the framework of the fib ModelCode1978. Later on the ModelCode1990 was extended till a load dependency of the phenomena creep. However a lot of computer programs did not include these load dependency related to creep. It was easier to add a so-called time dependant factor to the original creep formulation coming from the fib ModelCode78. Modifications to the fib ModelCode1990 (and properly also the fib ModelCode2010) will lead to better deformation predictions which will be shown in this paper.

Holguin-Veras J.,Center for Infrastructure | Holguin-Veras J.,Rensselaer Polytechnic Institute | Allen B.,KLD Associates Inc.
Transportation Research Part A: Policy and Practice | Year: 2013

Time of day pricing uses higher tolls in the peak-hours to induce passenger car traffic to consider a switch to more sustainable alternatives in terms of time of travel, mode, route, and payment method. In designing such programs, special attention must be paid to ensure that the drivers' behavioral responses to pricing are well understood. This is important because, if the analysts do not correctly predict users' reactions, policies and programs may fail to achieve their objectives. Knowledge of users' responses to pricing assists policy makers to design effective pricing programs.This paper investigates the behavioral impacts of time of day pricing using stated preference data collected from regular users of the New Jersey Turnpike. As part of the data collection process, the respondents were presented with hypothetical toll scenarios and asked how they would change behavior. Using these data, discrete choice models were estimated as a function of policy variables and respondents' socio-economic attributes. The final model shows that time of day pricing could induce changes in the payment method used to pay the tolls, route choice, and time of travel. It was found that the amount of the toll, total travel time, and schedule delay-together with other socio-economic variables-were important factors in determining which alternative a user would select. Market share analyses for basic toll scenarios were conducted to assess the overall impacts of alternative toll scenarios. Elasticities were computed for the key variables in the model. In its final sections, the paper discusses policy implications and chief conclusions. © 2013 Elsevier Ltd.

Gulikers J.,Center for Infrastructure
Applications of Statistics and Probability in Civil Engineering -Proceedings of the 11th International Conference on Applications of Statistics and Probability in Civil Engineering | Year: 2011

With respect to durability of existing reinforced concrete structures a practical approach has been developed to quantify the present condition level of individual structural components based on results obtained from in-situ measurements combined with information gained by visual inspection. In addition a detailed calculation procedure has been elaborated as to take into account degradation over time. For existing structures the focus is placed on reinforcement corrosion induced by chloride-ingress. The approach adopted is semi-probabilistic in nature by considering spatial and random variability of cover depth, critical chloride content, and measured chloride profiles. © 2011 Taylor & Francis Group, London.

Tromp L.,Royal HaskoningDHV | De Boer A.,Center for Infrastructure
Engineering for Progress, Nature and People | Year: 2014

Around the world the number, size and level of complexity of FRP structures in infrastructure increases rapidly, and it is seen that also for traffic bridges and lock doors FRP is selected in commercial projects. The main challenge in design guidance is the fact that FRP can be made by many different processes with varying degrees of automation. So how can we deal with this variety? How do we take the limited experience branch wide into account? The CUR 96 [1] is the Dutch Design Guidance for FRP in Infrastructure (2003). It is currently being revised into Eurocode format and chapters are added dealing with aspects such as quality control and design verification by tests. The partial factors of the CUR96 guidance were compared to material test data on samples that have been exposed to water for 10 years. Due to the limited number of samples this cannot be considered as a full calibration but allows for a valuable assessment of the validity of the factors.

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