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Abstract: By analyzing COSMIC data, found more than 50% reduction in electron density during a solar eclipse at the F2-layer and above, with the peak of ∼70% at 370km. So great eclipse effect on topside ionosphere was very abnormal and much different from previous studies. However, by comparing the cosmic data with IRI results, we find that the abnormal reduction comes mainly from the significant local time variation at sunrise, not from the eclipse effect. Furthermore, we simulated the eclipse effect by using a theoretical model to confirm our analysis. [Copyright &y& Elsevier]

The paper describes the recent devastating landslide of Kotrupi, Himachal Pradesh in India which had claimed many human lives and properties along its course on 13 August 2017. This event was the third reactivation of the slide as per data available. The study for this landslide involves a preliminary investigation of the site and comparison of pre- and post-event slope stability analysis. Other than rainfall, the combined effect of differential weathering rate of the debris and soil layers, low material strength, and the presence of a fault zone was found to be the primary cause of instability. The analysis was carried out with the geotechnical investigation and numerical modeling with the help of finite element model-based Phase 2 simulator. The significant findings of this paper include numerical simulation of pre- and post-event slide as stated under unsaturated and saturated condition. The study finds a low factor of safety of the present slope. The unstable condition of the slope may trigger another event of the same intensity shortly. [ABSTRACT FROM AUTHOR]

The paper reports an investigation on the requirement of fare increment for achieving the operational viability of private buses in the context of an emerging country. Taking an existing route in Kolkata city which is served by private buses, several scenarios were investigated to achieve the viability of service through interventions in fare, design of service, and supply of buses. A simulation framework was used for the evaluation of various scenarios. The study brings out new evidences to question the conventional approach of increasing the bus fare to satisfy the operational viability. It is shown that the fare and the revenue requirements are distorted due to the oversupply of buses and non-optimal service. The analysis shows that even with the present fare, it is possible to resolve the viability issue by optimizing the service and supply. The results presented in the paper are case specific but are likely to encourage policy makers to carry out similar investigations in other cities in India as well as in other developing countries to improve urban bus service without putting an additional burden on the users. [ABSTRACT FROM AUTHOR]

The selection of career paths and making of academic choices is a difficult and often confusing task for young people. The impact on their lives, however, is enormous as it can determine entire future career possibilities. In India, a general remedy to this stress is that instead of choosing a field of study tailored to individual preferences and strengths, topics are chosen that align with the choices of the students' families or their friends. This can have the effect of entrenching patterns of intergenerational inequity. The aim of this research is to give students greater access to the knowledge capital which will help them make better choices. This is achieved by engaging students in the career planning process, in order to convey information in a likeable and credible way. The COMPCAT (Competency and Career Assessment Tool) game engine combines the use of learning analytics and real time, interactive computer simulations designed to gain insights into the students' engagement in the making of these complex decisions. This paper presents the conceptual architecture of the game and demonstrates its role in enhancing the learning effectiveness of the students. [ABSTRACT FROM AUTHOR]

In this paper, a game-theoretic framework is applied in order to model the competition scenario between high-speed rail (HSR) and airlines in the Indian context and assess the impact of speed and passengers' characteristics on the equilibrium of the game. The competition is modelled in terms of the fare and frequency offered by the operators to maximize their profits. The speed of HSR is taken as an additional strategic variable in the game with three levels of high speed: low, medium, high. A three-stage game is formulated with the entrant playing its speed strategy in the first stage followed by optimal fare and frequency selection by both the modes. Passengers are considered to be heterogeneous in nature by assuming a continuous distribution of the value of time. Numerical simulations indicate that the dominant strategy for airlines and HSR is based on accommodation and medium speed, respectively. [ABSTRACT FROM AUTHOR]

The geotechnical assessment, safe design and monitoring of highwalls is one of the major challenges in Indian open pit mines. The aim of opencast mines should be to attain steepest possible slope angle without compromising safety in order to maximize profits. Highwall stability is essential for economical and safe exploitation of mineral during open pit mining. Geotechnical investigations are required to quantify the properties of soils and rocks within the mining horizons. The required minimum safety factor for highwalls is 1.2. Highwall should be monitored during open pit operations. This paper addresses the main elements of pit slope failure, accident statistics, design, and monitoring and pit slope management and also the guidelines for safe design and monitoring of open pit highwalls in India. [ABSTRACT FROM AUTHOR]

Purpose: Previous studies using the WHOQOL measures have demonstrated that the relationship between individual items and the underlying quality of life (QoL) construct may differ between cultures. If unaccounted for, these differing relationships can lead to measurement bias which, in turn, can undermine the reliability of results.Methods: We used item response theory (IRT) to assess differential item functioning (DIF) in WHOQOL data from diverse language versions collected in UK, Zimbabwe, Russia, and India (total N = 1332). Data were fitted to the partial credit 'Rasch' model. We used four item banks previously derived from the WHOQOL-100 measure, which provided excellent measurement for physical, psychological, social, and environmental quality of life domains (40 items overall). Cross-cultural differential item functioning was assessed using analysis of variance for item residuals and post hoc Tukey tests. Simulated computer-adaptive tests (CATs) were conducted to assess the efficiency and precision of the four items banks.Results: Splitting item parameters by DIF results in four linked item banks without DIF or other breaches of IRT model assumptions. Simulated CATs were more precise and efficient than longer paper-based alternatives.Discussion: Assessing differential item functioning using item response theory can identify measurement invariance between cultures which, if uncontrolled, may undermine accurate comparisons in computer-adaptive testing assessments of QoL. We demonstrate how compensating for DIF using item anchoring allowed data from all four countries to be compared on a common metric, thus facilitating assessments which were both sensitive to cultural nuance and comparable between countries. [ABSTRACT FROM AUTHOR]

Abstract: A lecture theatre with dimension 16m×8.4m×3.6m located at Roorkee (28.58°N, 77.20°E) in the northern region of India, is selected to calculate the monthly and annual cooling load (kWh) and cooling capacity of air conditioning system by a computer simulation. The paper also presents the results of a study investigating the effect of different glazing systems on windows and the reduction in building cooling load. DesignBuilder software has been used for the computer simulation for calculating the cooling load. The paper aims to investigate the reduction in thermal gains and cooling load requirements by varying the U-values of different glazing types, insulating the ceiling, providing cool roofs, interior and exterior insulation on walls, and replacing the conventional fluorescent tube lamp (FTL) by energy efficient compact fluorescent lamp (CFL). Installation of false ceiling, wall insulation, different glazing types and lighting systems are cost effective with normalized annual saving ranging from 17% to 19.8% from this retrofitting project. Furthermore, the study also highlights the potential of reducing the emission of CO2 and equivalent carbon credit. Retrofitting techniques strongly influence the level of energy saving, although the payback period is generally quite long of order 8years. [Copyright &y& Elsevier]

In tropical countries such as India, increasing the roof albedo helps to reduce the heat ingress through the roof. This further reduces air-conditioning energy consumption in conditioned buildings and increases comfort in unconditioned buildings. In order to help users determine the benefits of high albedo roofs under varying conditions, a simple calculator has been developed. Parameters such as location, building type, roof area, and surface properties of the roof are taken as inputs. Annual EnergyPlus simulations are performed for the given parameters and the results are displayed in both graphical and tabular formats. It also calculates the simple payback by comparing a given base case roof albedo with the proposed roof albedo. The calculator can perform comfort simulations for unconditioned buildings and simulates measures including a radiant barrier system and under deck roof insulation. The calculator also runs a parametric simulation between insulation thickness and roof albedo to find an optimum roof insulation thickness based on incremental internal rate of return. This paper presents the features of the cool roof calculator and the type of analysis that can be performed using the cached results. [ABSTRACT FROM AUTHOR]

Intervention programs aimed at preventing tobacco use among youth have been shown to be effective in curbing tobacco use onset and progression. However, the effects of even very successful tobacco prevention programs may not always impress policy-makers and lay audiences. Economic analysis potentially strengthens the case. In this paper, we evaluate the cost-effectiveness of a youth tobacco use prevention program which has been translated and implemented in India, a developing country. Although programs like these are inexpensive to implement in the USA, they are even less expensive in India due to low labor costs. Our results show that the costs per quality-adjusted life-year added, due to averted smoking, was $2057, even without including averted medical costs. If we ignore student time, cost-effectiveness improves by roughly 10%. To put the cost-effectiveness of this smoking prevention program into context, it is over 24 times more cost-effective than dialysis in the USA, which costs $50 000 for a life-year. [ABSTRACT FROM PUBLISHER]

Abstract: The Overall Index of Pollution (OIP) is a single number that expresses the overall water quality by integrating measurements of 14 different physicochemical, toxicological, and bacteriological water quality parameters. It provides a simple and concise method for water quality classification as, ‘Excellent’, ‘Acceptable’, ‘Slightly Polluted’, ‘Polluted’, and ‘Heavily Polluted’. OIP values range from 0 to 16. A high OIP value signals poor water quality, while a low value signals good water quality based on the classification scheme developed for India. In this paper, we present a computer-automated, user-friendly, and standalone Surface Water Quality Assessment Tool (SWQAT), which calculates OIP values and displays it on Google map. The software is developed in VB.Net and SQL database. The software application is demonstrated through water quality assessment of two rivers of India, namely Cauvery and Tungabhadra. OIP values are estimated at 10 sampling stations on the river Cauvery and at eight sampling stations on the river Tungabhadra. The Cauvery river OIP scores in the range 0.85–7.91 while for Tungabhadra river, it is in range 2.08 to 8.97. The results are useful to analyze the variations in the water quality of different sites at different times. SWQAT improves understanding of general water quality issues, communicates water quality status, and draws the need for and effectiveness of protection measures. [Copyright &y& Elsevier]

In this paper, a computational model for the prediction of direct solar radiation based on neural network analysis of atmospheric clearness is developed. It considers that the major portion of direct solar radiation reaching the earth's surface is governed by Sun-Earth geometry and atmospheric transmittance factors which are exactly calculable by clear day model. Additional variations are due to climate and weather phenomena characterized by relative humidity, mean duration of sunshine per hour, and rainfall, etc., in the atmosphere. These variations are taken into account with the help of a composite parameter referred to as atmospheric clearness index (CI) which is determined using artificial neural network analysis. The contour maps of CI as a function of latitude, time of the day, and month of the year are then prepared using the meteorological data of eleven stations. Model simulation and test results of the trained network for two typical locations (not used in training the network) are presented and compared with measured values. The deviations are well within acceptable error limits [percentage root mean square error values for Ahmedabad and Nagpur are 3.34 and 2.06, respectively]. The methodology, for predicting the direct solar radiation at an arbitrary location using the well known parameters such as altitude, latitude, time of the day, day of the year, and CI values derived from the contour maps, is discussed. The outcome of the present ANN model for four arbitrary locations is compared with NASA SSE data sets. [ABSTRACT FROM AUTHOR]

Silicon Drift Detectors (SDDs) are being developed for low energy (0.12 keV to 12 keV) X-ray spectroscopy and position sensing applications using silicon bipolar technology available with Bharat Electronics Ltd (BEL), Bangalore. As a part of this development, the first batch of proto-type SDDs have been realized through a pilot stage fabrication run at the Micro-fabrication facility at Indian Institute of Technology - Bombay (IIT-B). This paper presents a detailed view on the design; fabrication and characterization of the first prototypes of SDDs. SDDs fabricated at IIT-Bombay were characterized to extract critical dc (I-V and C-V) performance parameters like total leakage current at anode, full depletion anode capacitance and full depletion voltage. Device simulations in Technology Computer Aided Design (TCAD) were employed to extract analytical values of these performance parameters. Based on the results from characterization of proto-type SDDs developed at IIT-B, the mask layout consisting of various designs of SDDs and JFETs to be fabricated at BEL was designed. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents the results of the application of model (developed in part I) and simulation algorithm (developed in part II) for determining the techno-economics of battery storage type hybrid energy system intended to supply the load of a rural remote area having a cluster of nine villages (grid isolated). The hour-by-hour simulation model is intended to simulate a typical one month period of system operation. For simulation purpose, hourly solar insolation data and load data have been generated and used as an input data. Demand side management (DSM) is used in this study to smooth out the daily peaks and fill valleys in the load curve to make the most efficient use of energy sources. The economic analysis has resulted in the calculation of optimized hourly, daily, and monthly system unit cost of proposed hybrid energy system. The obtained results represent also a helpful reference for energy planners in Uttarakhand state and justify the consideration of hybrid energy systems more seriously. [ABSTRACT FROM AUTHOR]

Study of the basic traffic-flow characteristics and clear understanding of vehicular interaction are the prerequisites for highway capacity and level of service analyses and to formulate effective traffic regulation and control measures. Computer simulation has emerged as an effective technique for modeling traffic flow and to study the flow characteristics over a wide range of roadway and traffic conditions due to its capability to account for the randomness related to traffic. This paper is concerned with application of a simulation model of heterogeneous traffic flow, named HETEROSIM, to quantify the vehicular interaction, in terms of passenger car unit (PCU), for the different categories of vehicles, by considering the traffic flow of representative composition, on up-grades of different magnitudes for intercity roads in India. The PCU estimates, determined through microscopic simulation, for the different types of vehicles in heterogeneous traffic, for a wide range of grades and traffic volumes, indicate that the PCU value of a vehicle significantly changes with change in traffic volume and magnitude of grade and its length. [ABSTRACT FROM AUTHOR]