6,736 research outputs found
Design and Development of an Airblast Atomiser for the KAVERI engine and the sectoral combustor tests
This report deals with the design and development
of an airblast atomiser for application in the KAVERI
engine. Five atomisers of the chosen design were
fabricated and tested at ambient conditions to determine
the fuel spray SMD, patternation, cone angle
and atomiser flow number. The atomiser performance
parameters specified were achieved and hot tests
carried out in the 90° combustor sector. The combustor
pressure loss, exit temperature distribution, ignition
and stability limits were evaluate
Dendroclimatic analysis of teak (Tectona grandis L. f.) annual rings from two locations of peninsular India
Climate-related tree-growth variability in teak (Tectona grandis L. f.) has been studied based on response function analysis from dry deciduous forests of Mundagod (Karnataka) and Chandrapur (Maharashtra), peninsular India, representing two ecological zones. Rainfall during the monsoon months of the current year was found to be positively associated with radial growth of teak at both sites, whereas premonsoon April rainfall was found to be negatively associated. Rainfall and temperature of the current year during March have positive influence on the growth of teak at Chandrapur and Mundagod respectively. Furthermore, rainfall during October of the preceding year showed negative influence on tree growth at Mundagod and positive influence at Chandrapur, which might be due to the difference in relative humidity and soil type at both the locations, apart from soil moisture
An isobar contour plot progrz
A computer program was developed to obtain ; isobar contours from the total pressure measurements at the engine face of an 1/3 scale model of an aircraft intake duct provided by ADA . A cubic spline method was used to interpolate the total pressure value between the measuring stations . The isobar contour plots were obtained for engine face Mach numbers\ud
varying from 0.17 to 0 .43
Variation in the ionic composition in convective showers in Pune, India
Rain water samples of equal volume (100 ml) were collected sequentially from 5 convective shower events for a period of 2 years during the summer monsoon seasons of 1988 and 1989 at Pune. A marked decrease in the concentrations of soil-oriented elements Na+, K+, Ca2+ and Mg2+ was observed in the first few samples in all the events followed by a decrease in pH of the subsequent samples. Surprisingly, SO42- also showed similar variation, indicating that soil is contributing some SO42- in rain water. Washout process appears to be an important mechanism for the removal of the major ions from the atmosphere. However, rainout processes seem to be important for the removal of NO3- ions. The study points out that sequential sampling during a single shower appears to give better information about the relationship among H+, Na+, K+, Ca2+, Mg2+, SO42- and NO3- as compared to bulk sampling for longer duration
Role of atmospheric stability over the Arabian Sea and the unprecedented failure of monsoon 2002
The anomalous behaviour of the monsoon 2002 has been studied. We have made an attempt to combine satellite and other data sources to characterize the thermal stratification over the Arabian Sea during different phases of monsoon 2002. Using NOAA-ATOVSderived atmospheric temperature and moisture profiles, we have calculated a daily stability index (SI) over the entire Indian region and surrounding oceans. The time series of SI clearly brings out the three major significant epochs of monsoon 2002. The relatively dry atmosphere west of 65° E, signifying lack of convection and an unstable atmosphere over the southeast Arabian Sea with west-to-east gradients in water vapour, SI and cloud liquid water content are noted. The unfavourable stratification during July over the entire Arabian Sea has been investigated in detail. The dominant modes of instability oscillations have been seen to be ~ 30 days both over the western and eastern Arabian Sea, while for the high-frequency modes preference was seen over the eastern part. Using the analysed fields of the National Centre for Medium Range Weather Forecasts, the relative contributions of advective and subsidence components in the maintenance of stratification have been investigated. The latter has been found to have played a more dominant role in the deficit monsoon 200
Probabilistic Perception Revision in AgentSpeak(L)
Agent programming is mostly a symbolic discipline and, as such, draws little benefits from probabilistic areas as machine learning and graphical models. However, the greatest objective of agent research is the achievement of autonomy in dynamical and complex environments — a goal that implies embracing uncertainty and therefore the entailed representations, algorithms and techniques. This paper proposes an innovative and conflict free two layer approach to agent programming that uses already established methods and tools from both symbolic and probabilistic artificial intelligence. Moreover, this method is illustrated by means of a widely used agent programming example, GOLDMINERS
On the moment limit of quantum observables, with an application to the balanced homodyne detection
We consider the moment operators of the observable (i.e. a semispectral
measure or POM) associated with the balanced homodyne detection statistics,
with paying attention to the correct domains of these unbounded operators. We
show that the high amplitude limit, when performed on the moment operators,
actually determines uniquely the entire statistics of a rotated quadrature
amplitude of the signal field, thereby verifying the usual assumption that the
homodyne detection achieves a measurement of that observable. We also consider,
in a general setting, the possibility of constructing a measurement of a single
quantum observable from a sequence of observables by taking the limit on the
level of moment operators of these observables. In this context, we show that
under some natural conditions (each of which is satisfied by the homodyne
detector example), the existence of the moment limits ensures that the
underlying probability measures converge weakly to the probability measure of
the limiting observable. The moment approach naturally requires that the
observables be determined by their moment operator sequences (which does not
automatically happen), and it turns out, in particular, that this is the case
for the balanced homodyne detector.Comment: 22 pages, no figure
Cross-sectional associations between sleep duration, sedentary time, physical activity, and adiposity indicators among Canadian preschool-aged children using compositional analyses
Abstract Background Sleep duration, sedentary behaviour, and physical activity are three co-dependent behaviours that fall on the movement/non-movement intensity continuum. Compositional data analyses provide an appropriate method for analyzing the association between co-dependent movement behaviour data and health indicators. The objectives of this study were to examine: (1) the combined associations of the composition of time spent in sleep, sedentary behaviour, light-intensity physical activity (LPA), and moderate- to vigorous-intensity physical activity (MVPA) with adiposity indicators; and (2) the association of the time spent in sleep, sedentary behaviour, LPA, or MVPA with adiposity indicators relative to the time spent in the other behaviours in a representative sample of Canadian preschool-aged children. Methods Participants were 552 children aged 3 to 4 years from cycles 2 and 3 of the Canadian Health Measures Survey. Sedentary time, LPA, and MVPA were measured with Actical accelerometers (Philips Respironics, Bend, OR USA), and sleep duration was parental reported. Adiposity indicators included waist circumference (WC) and body mass index (BMI) z-scores based on World Health Organization growth standards. Compositional data analyses were used to examine the cross-sectional associations. Results The composition of movement behaviours was significantly associated with BMI z-scores (p = 0.006) but not with WC (p = 0.718). Further, the time spent in sleep (BMI z-score: γ sleep = −0.72; p = 0.138; WC: γ sleep = −1.95; p = 0.285), sedentary behaviour (BMI z-score: γ SB = 0.19; p = 0.624; WC: γ SB = 0.87; p = 0.614), LPA (BMI z-score: γ LPA = 0.62; p = 0.213, WC: γ LPA = 0.23; p = 0.902), or MVPA (BMI z-score: γ MVPA = −0.09; p = 0.733, WC: γ MVPA = 0.08; p = 0.288) relative to the other behaviours was not significantly associated with the adiposity indicators. Conclusions This study is the first to use compositional analyses when examining associations of co-dependent sleep duration, sedentary time, and physical activity behaviours with adiposity indicators in preschool-aged children. The overall composition of movement behaviours appears important for healthy BMI z-scores in preschool-aged children. Future research is needed to determine the optimal movement behaviour composition that should be promoted in this age group
Characteristics of aerosols at traffic junctions in Pune city
Vehicular emissions are one of the potential sources of air pollution in the urban regions. Pune, one of the rapidly growing cities of India, faces the severe threat from this problem. Observations of total suspended particulates and Aitken nuclei were conducted at 4 traffic junctions in Pune city during summer (May 2000) and winter (Jan-Feb. 2001). Concentrations of TSP crossed the CPCB limit, recommended for commercial zone, at all the traffic junctions and also the number density of Aitken nuclei was very high. However, aerosols were alkaline in nature, in spite of high concentrations of SO4 and NO3, mainly due to the neutralizing effect of Ca, NH4, Na, Mg and K
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