Showing papers by "Prashant Kumar published in 2011"

Preliminary estimates of nanoparticle number emissions from road vehicles in megacity Delhi and associated health impacts.

Abstract: Rapid urbanisation in developing megacities like Delhi has resulted in an increased number of road vehicles and hence total particle number (ToN) emissions. For the first time, this study presents preliminary estimates of ToN emissions from road vehicles, roadside and ambient ToN concentrations, and exposure related excess deaths in Delhi in current and two future scenarios; business as usual (BAU) and best estimate scenario (BES). Annual ToN emissions are estimated as 1.37 × 10(25) for 2010 which are expected to increase by ∼4 times in 2030-BAU, but to decrease by ∼18 times in 2030-BES. Such reduction is anticipated due to a larger number of compressed natural gas driven vehicles and assumed retrofitting of diesel particulate filters to all diesel vehicles by 2020. Heavy duty vehicles emit the majority (∼65%) of ToN for only ∼4% of total vehicle kilometres traveled in 2010. Their contribution remains dominant under both scenarios in 2030, clearly requiring major mitigation efforts. Roadside and ambient ToN concentrations were up to a factor of 30 and 3 higher to those found in respective European environments. Exposure to ambient ToN concentrations resulted in ∼508, 1888, and 31 deaths per million people in 2010, 2030-BAU and 2030-BES, respectively.

Negotiation on the assessment of research articles with academic reviewers: Application of peer-review approach of teaching

Abstract: This study provides an insight into the dominant negotiation processes that occur between the authors of research articles and academic reviewers at the peer reviewing stage. Data of reviewers comments and authors responses on 32 science and engineering based journal articles covering four decision categories (accept as is, accept with minor revisions, major revisions and reject) were collected. A commonly practised peer-review approach in teaching was applied to analyse the data and to identify the key negotiation attributes, their frequency of occurrence, authors’ reaction and approach to negotiate with the reviewers. Six main negotiation attributes were identified. Technical quality was the most frequent (31% of all instances) attracting mixed reactions from the authors. The remaining attributes constituted suggestion (20%), explanation (20%), restatement (15%), grammar (13%) and structure (~1%). With the exception of ‘explanation’ where authors had to counteract to clear misunderstood concepts or contents by the reviewers, the other attributes were of highly collaborative nature and were willingly accepted by the authors. All these negotiations were found to help authors in improving the overall quality, clarity and readability of their manuscripts, besides forcing them to rethink about unclear contents. The negotiation trends emerged here can help the academic researchers to improve the quality of their articles before submission to the peer-reviewed journals. It can also provide a link through which their classroom teaching experience involving supervision of peer review negotiations among students can be utilised in writing their research articles and negotiating with academic reviewers.

Improving Student Learning in Engineering Discipline Using Student- and Lecturer-Led Assessment Approaches.

Abstract: This article investigates the effectiveness of two distinct formative assessment methods for promoting deep learning and hence improving the performance amongst engineering students. The first method, applied for undergraduate students, employs a lecturer-led approach whereas the second method uses a student-led approach and e-learning for postgraduate teaching. Both studies demonstrate that the formative assessment and feedback has a positive effect on the performance of engineering students, especially those lying on the middle and lower grade tail. The mean exam marks increased by 15 to 20% as a result of introducing formative assessment to the case study modules. The main catalysts for performance improvement were found to be the feedback provided by the lecturer to the students, and by the students to their peer partners. Comparison of the two practices leads to the conclusion that whilst both methods are equally effective, peer assessment requires less time commitment from the lecturer.

Effect of integrated nutrient management on quality of broccoli (Brassica oleracia var. italica) cv. Fiesta under Jharkhand conditions.

Abstract: An investigation was carried out at Birsa Agricultural University, Ranchi during 2008-09 and 2009-10 to standardize integrated nutrient management for broccoli under Jharkhand conditions. The experiment consisted of 19 treatments i.e., four inorganic combinations 200:100:100 kg NPK, 150:75:75 kg NPK, 100:50:50 kg NPK and 50:25:25 kg NPK ha, 12 organic and inorganic combinations by substituting 25 per cent N of above inorganic combinations through FYM, vermicompost and karanj cake along with recommended dose 100:50:50 kg NPK + 200 q FYM ha and two controls N 0 P 100 K 100 and N 0 P 0 K 0 . Treatments with high as well as lower content of total nutrient resulted in significantly lower TSS and soluble carbohydrate whereas higher sugar content was obtained with application of higher dose of nutrient and vermicompost. Treatments with lower content of nutrients resulted in maximum phenol content while treatments without nitrogen resulted in minimum content of total soluble protein. With respect to content of ascorbic acid in the curd, the maximum value was recorded in case of treatments without application of nitrogen.

Technical challenges in tackling regulatory concerns for

Abstract: 14 Recent Euro–5 and Euro–6 vehicle emission standards are the first ever initiative to 15 control particles on a number basis at the source. Related standards are also desirable 16 for ambient nanoparticles (taken in this article to be those below 300 nm) to protect 17 against possible adverse impacts on public health and the environment. However, 18 there are a number of technical challenges that need to be tackled before developing a 19 regulatory framework for atmospheric nanoparticles. Some of the challenges derive 20 from a lack of standardisation of the key measurement parameters, including 21 sampling, necessary for robust evaluation of particle number concentrations, 22 especially in the context of insufficient knowledge of the physicochemical 23 characteristics of emerging sources (i.e. bio–fuel derived and manufactured 24 nanoparticles). Ideally, ambient concentrations of primary particles could be linked to 25 primary particle emissions by use of nanoparticle dispersion models, and secondary 26 nanoparticles using photochemical modelling tools. The limitations in these areas are 27 discussed. Although there is inadequate information on the exact biological 28 mechanism through which these particles cause harm, it is argued that this should not 29 in itself delay the introduction of regulation. This article reviews the missing links 30 between the existing knowledge of nanoparticle

Understanding dispersion of nanoparticles in vehicle wakes combining field measurements and wind tunnel simulations

Abstract: This work presents selected results of an EPSRC-funded project investigating the dispersion of nanoparticles in the wake of moving vehicles. The aims were to study the changes in particle number distribution (PND) due to the competing effects of dilution and transformation processes (e.g. coagulation, nucleation, condensation) over the travel time from tailpipe to roadside, and to model the fate of these particles in the near and the far wake regions of a moving vehicle. To achieve these objectives, firstly ground-fixed and on-board measurements of PNDs were performed using a fast response (sampling frequency up to 10Hz) differential mobility spectrometer (Cambustion DMS50) in the wake of a diesel engined car moving at a range of speeds from 20 to 50 km h -1 . Secondly, wind tunnel simulations were carried out on reduced scale (1:5 and 1:20) models of the car used for the field experiments. The flow and turbulence fields were characterised both in the near and far wake of the modelled vehicle by using a two component laser Doppler anemometer. Concentration measurements were obtained by using a fast response (frequency >350 Hz) flame ionisation detector and a hydrocarbon tracer gas released from the modelled tailpipe. A high resolution experimental data base was obtained from both the field and wind tunnel measurements for formulating the basis of fast mathematical parameterisations that can be used with operational nanoparticle dispersion models.