Multi-user Internet environment for gear design optimization

A Web based multi-user system has been developed to remotely execute a large size software package via the Internet. The software implements genetic algorithm to optimize the design of spur and helical gears. To accomplish this, a combination of HTML, JavaServlets, JavaApplets, JavaScript and HTTP protocol has been employed

Rare-male mating advantage in Drosophila ananassae

International audienc

Observation of guanidine-carbon dioxide complexation in solution and its role in reaction of carbon dioxide and propargylamines

The first observation of guanidine-CO2 'activation' complexes in solution using ATR-FTIR is reported. While cyclic guanidines TBD and MTBD form stable and detectable complexes with CO2, other guanidines and tertiary amines do not. Correlation with catalytic activity of these amines/guanidines in reaction between CO2 and propargylamines indicated that the basicity of the catalyst, rather than its ability to form complexes with CO2, is the origin of catalytic activity

Pacific coral oxygen isotope and the tropospheric temperature gradient over the Asian monsoon region: A tool to reconstruct past Indian summer monsoon rainfall

Having recognized that it is the tropospheric temperature (TT) gradient rather than the land-ocean surface temperature gradient that drives the Indian monsoon, a new mechanism of El Niño/Southern Oscillation (ENSO) monsoon teleconnection has been unveiled in which the ENSO influences the Indian monsoon by modifying the TT gradient over the region. Here we show that equatorial Pacific coralline oxygen isotopes reflect TT gradient variability over the Indian monsoon region and are strongly correlated to monsoon precipitation as well as to the length of the rainy season. Using these relationships we have been able to reconstruct past Indian monsoon rainfall variability of the first half of the 20th century in agreement with the instrumental record. Additionally, an older coral oxygen isotope record has been used to reconstruct seasonally resolved summer monsoon rainfall variability of the latter half of the 17th century, indicating that the average annual rainfall during this period was similar to that during the 20th century

Experimentation and Prediction of Temperature Rise in Turning Process using Response Surface Methodology

Reducing the temperature rise during turning operation improves the quality of the product and reduces tool wear. Experiments are conducted as per the Design of Experiments (DoE) of Response Surface Methodology (RSM) to predict the temperature rise by varying the cutting parameters such as cutting speed, feed rate and depth of cut. In the present study, the experiment was conducted on Aluminium Al 6061 by coated carbide tool. A second order mathematical model in terms of machining parameters was developed for temperature rise prediction using RSM. This model gives the factor effects of the individual process parameters. Values of Prob> F less than 0.05 indicate model terms are significant. The cutting speed is the most important parameter that cause the temperature of the turning process compared to the other factors such as feed rate and depth of cut. Validation results show good agreement between the actual process output and the predicted temperature rise

The Past Has Ears (PHE): XR Explorations of Acoustic Spaces as Cultural Heritage

Hearing is one of our most pervasive senses. There is no equivalent to closing our eyes, or averting our gaze, for the ears. When we think about great architectural achievements in European history, such as ancient amphitheatres or Gothic cathedrals, their importance is strongly tied to their acoustic environment. The acoustics of a heritage site is an intangible consequence of the space's tangible construction and furnishings. Inspired by the project's namesake (Phe, for the constellation Phoenix), and the relatively recent res at Cathedrale de Notre Dame de Paris and Teatro La Fenice opera hall, the PHE project focuses on virtual reconstruction of heritage sites, bringing them back from the ashes. In addressing the intangible acoustic heritage of architectural sites, three main objectives have been identied for this research project: Documentation, Modelling, and Presentation. In parallel, three heritage sites are participating as case studies: Tindari Theatre (IT), Notre-Dame de Paris Cathedral (FR), and The Houses of Parliament (UK). The acoustics of a space is immersive, spatial, and due to the nature of auditory perception egocentric, in contrast to visual perception of an object, which can be observed from outside". Consequently, presentation methods for communicating acoustic heritage must represent the spatially immersive and listener-centric nature of acoustics. PHE will lead development of a museum grade hardware/software prototype for the presentation of immersive audio experiences adaptable to multiple platforms, from on-site immersive speaker installations, to mobile XR via smartphone applications

Low-Latency Routing on Mesh-Like Backbones

Early in in the Internet's history, routing within a single provider's WAN centered on placing traffic on the shortest path. More recent traffic engineering efforts aim to reduce congestion and/or increase utilization within the status quo of greedy shortest-path first routing on a sparse topology. In this paper, we argue that this status quo of routing and topology is fundamentally at odds with placing traffic so as to minimize latency for users while avoiding congestion. We advocate instead provider backbone topologies that are more mesh-like, and hence better at providing multiple low-latency paths, and a routing system that directly considers latency minimization and congestion avoidance while dynamically placing traffic on multiple unequal-cost paths. We offer a research agenda for achieving this new low-latency approach to WAN topology design and routing

Indian summer monsoon precipitation climatology in a high-resolution regional climate model: Impacts of convective parameterization on systematic biases

In an attempt to develop a better simulation of the climatology of monsoon precipitation in climate models, this paper investigates the impacts of different convective closures on systematic biases of an Indian monsoon precipitation climatology in a high-resolution regional climate model. For this purpose, the Weather Research Forecast (WRF) model is run at 45- and 15-km (two-way nested) resolution with three convective parameterization schemes, namely the Grell-Devenyi (GD), the Betts-Miller-Janji (BMJ), and the Kain-Fritsch (KF), for the period 1 May-31 October 2001-07. The model is forced with the NCEP-NCAR reanalysis data as the initial and boundary conditions. The simulated June-September (JJAS) mean monsoon rainfall with the three convective schemes is compared with the observations. KF is found to have a high moist bias over the central and western coastal Indian region while GD shows the opposite. Among the three, BMJ is able to produce a reasonable mean monsoon pattern. In an attempt to get further insight into the seasonal bias and its evolution, the probability distribution function (PDF) of different rain-rate categories and their percentage contribution to the seasonal total are computed. BMJ and KF underestimate the observations for lighter rain rates and overestimate for rain-rate categories of more than 10 mm day -1. GD shows an overestimation for lighter rain and an underestimation of PDF for moderate categories. The seasonal patterns of evolution of PDF plots of three rain-rate categories are analyzed to determine whether the convective schemes show any systematic bias throughout the season or if they have problems during certain phases of the monsoon. This shows that the GD systematically overestimates the lighter rain rate and underestimates the moderate rain rate throughout the season, whereas BMJ and KF have problems in the initial stages. The heavy rain category is systematically overestimated by the KF compared to the other two. To further evaluate the proportionate contribution of each rain-rate bin to the total rain, the percentage contribution of each rain rate to the seasonal total is computed. Analyzing all the rain-rate simulations produced by the three schemes, it is found that KF has a moist bias and GD has a dry bias in the spatiotemporal distribution of the monsoon precipitation. Further, this paper investigates the causes behind the mean monsoon precipitation bias. It is shown that GD produces a model climate where the vertical velocity is less than that of the observations up to 500 hPa and the vertically integrated moist instability is also weaker. KF, on the other hand, shows a higher than the observed vertical velocity and a stronger moist instability. Along with this, the vertical profile of heating suggests a warmer middle level in the KF case and significantly reduced midlevel heating for GD. Thus, KF (GD) has produced a model atmosphere that has a stronger (weaker) convective instability to produce the observed bias in the model precipitation. BMJ is found to simulate a reasonable heating profile, along with the realistic moist instability and seasonal cycle of evaporation and condensation. Insight derived from the analysis is expected to help improve the convective parameterizations

COMPARATIVE STUDIES WITH DIFFERENT CYCLODEXTRIN DERIVATIVES IN IMPROVING THE SOLUBILITY AND DISSOLUTION OF SAQUINAVIR

Objective: The present study was aimed to perform comparative studies with different cyclodextrin (CD) derivatives and to study the effect of different methods of preparation in improving the solubility and dissolution of saquinavir (SQV).Methods: Phase solubility studies were performed with beta CD (βCD), hydroxypropyl βCD, randomly methylated βCD, and sulfobutyl ether βCD (SBE7βCD). Complexes were prepared using physical mixture, coevaporation, kneading, spray drying, and freeze-drying techniques. For complexes prepared by spray drying, process parameters were optimized based on percentage yield. The prepared complexes were characterized using Fourier-transform infrared spectroscopy, differential scanning calorimetry, X-ray diffraction studies, nuclear magnetic resonance spectroscopy, and scanning electron microscopy. In vitro drug release study was conducted in phosphate buffer pH 6.8 and mean dissolution time (MDT) was calculated for all freeze-dried complexes.Results: Phase solubility studies showed a linear relationship with an increase in CD concentration and phase diagrams were of AL type. Highest stability constant was observed with SQV-SBE7βCD (8281.28/M). All characterization studies proved complexation. Among four CD derivatives, SQV complexed with SBE7βCD by freeze-drying showed maximum drug release and low MDT of 20.67.Conclusion: Among different CDs, SBE7βCD proved as ideal CD derivative, and among different methods of preparations, freeze-drying method was found to be useful in improving the solubility and dissolution of SQV