Snow depth as an indicator of weather and climate in the Sierra Nevada

EXTRACT (SEE PDF FOR FULL ABSTRACT): The purpose of this study is to determine: (1) whether the cooperative station snow depth contains useful weather and climate information, (2) how cooperative snow depth variability is related to snowcourse variability, and (3) how it is related to other weather elements. From an examination of stations in the Sierra Nevada of California, it is clear that cooperative snow records and snowcourse records have consistent spatial and temporal variability. ... We show that high snow ratio (low density snow or high SD/Ppt) events have low temperatures and high amplitude atmospheric circulation patterns over the eastern North Pacific. In contrast, low snow ratio (high density or low SD/Ppt) events have warm temperatures and a zonal flow pattern with a southerly displaced storm track from Hawaii to the West Coast.

On the operation of small shrimp trawls in shallow waters-scope-ratio and size-depth relation

Studies on small trawls seem to be comparatively less. These trawls are generally operated in shallower waters, where due to the limitations in the length of warp that could be released, size restrictions have to be considered for their efficient functioning. An attempt has been made to assess the effective scope-ratio of length of warp required for the operation of trawls at shallower depth and to a judge the size of trawl suitable for use at lower depths.

Seasonal variation of mixed layer depth in the north Arabian Sea

The Arabian Sea is unique due to the extremes in atmospheric forcing that lead to the semi-annual seasonal changes. The reversing winds of summer and winter monsoon induce the variation in the characteristics of mixed layer depth. The importance of mixed layer depth is recognized in studying the biological productivity in the ocean. In this paper variability of mixed layer depth in the north Arabian Sea have been discussed. The study is based on the data collected under North Arabian Sea Environment and Ecosystem Research (NASEER) program. The results of the study indicate that there is a significant variation in the mixed layer depth from summer to winter monsoon as well as coast to offshore.

Belly depth studies for shrimp trawls - Part II

The paper details further experiments conducted for a reduction in the depth of belly of a 13.69 m (45') four seam shrimp trawl net. The investigations have given conclusive evidence that the optimum depth of belly for this particular trawl design should be 70 meshes.

Low short term timing jitter in an integrated monolithic extended cavity semiconductor mode-locked laser

Jitter measurements were performed on a monolithically integrated active/passive cavity multiple quantum well laser, actively mode-locked at 10 GHz via modulation of an absorber section. Sub-10 ps pulses were produced upon optimization of the drive conditions to the gain, distributed Bragg reflector, and absorber sections. A model was also developed using travelling wave rate equations. Simulation results suggest that spontaneous emission is the dominant cause of jitter, with carrier dynamics having a time constant of the order of 1 ns.

Extended VTS for noise-robust speech recognition

Model compensation is a standard way of improving the robustness of speech recognition systems to noise. A number of popular schemes are based on vector Taylor series (VTS) compensation, which uses a linear approximation to represent the influence of noise on the clean speech. To compensate the dynamic parameters, the continuous time approximation is often used. This approximation uses a point estimate of the gradient, which fails to take into account that dynamic coefficients are a function of a number of consecutive static coefficients. In this paper, the accuracy of dynamic parameter compensation is improved by representing the dynamic features as a linear transformation of a window of static features. A modified version of VTS compensation is applied to the distribution of the window of static features and, importantly, their correlations. These compensated distributions are then transformed to distributions over standard static and dynamic features. With this improved approximation, it is also possible to obtain full-covariance corrupted speech distributions. This addresses the correlation changes that occur in noise. The proposed scheme outperformed the standard VTS scheme by 10% to 20% relative on a range of tasks. © 2006 IEEE.

Supply network integration in multi-organisational network systems

This paper explores supply network integration in complex product service systems involving close collaboration between primes. Four case study networks are studied (aerospace, naval, power and telecoms), each involving equipment manufacture and service provision. Factors that support network integration, identified from the literature and refined in the in-depth pilot case, were used to explore which processes support integration of the extended enterprise. Results suggests that a select set of processes support integration of the extended enterprise and that the absence of a shared view on these critical enabling processes results from contextual complexity of the network rather than from competing commercial interests. Copyright © 2011 Inderscience Enterprises Ltd.

Belly depth studies for shrimp trawls - Part III

Earlier investigations with 13.69 m (45') four seam shrimp trawl indicated the optimum depth of belly to be 70 meshes. Present communication details further experiments on similar lines with a bigger shrimp trawl of size 17.07 m (56') without overhang. The results obtained have not only given corroborating evidence in support of the earlier findings but also helped in arriving at a relationship that for a given stretched width of belly ‘L’ the stretched depth of belly could be either 2L/5 or 40% of ‘L’ with an allowance of ± 2 meshes.

Height-depth (breadth) relationship of shells in the backwater oyster Crassostrea madrasensin (Preston) of the Cochin harbour

A study of the height-depth relation in the Indian backwater oyster Crassostrea madrasensis (Preston) was carried out. The plot of height against depth showed an exponential trend and a relationship of the form H = ADB. Plot of height against depth also showed larger deviations in height for oysters with greater depth. Analysis showed that variations in height do not result in corresponding variations in depth, particularly in oysters with increased height.

Synchronization in climate dynamics and other extended systems

Synchronization is now well established as representing coherent behaviour between two or more otherwise autonomous nonlinear systems subject to some degree of coupling. Such behaviour has mainly been studied to date, however, in relatively low-dimensional discrete systems or networks. But the possibility of similar kinds of behaviour in continuous or extended spatiotemporal systems has many potential practical implications, especially in various areas of geophysics. We review here a range of cyclically varying phenomena within the Earth's climate system for which there may be some evidence or indication of the possibility of synchronized behaviour, albeit perhaps imperfect or highly intermittent. The exploitation of this approach is still at a relatively early stage within climate science and dynamics, in which the climate system is regarded as a hierarchy of many coupled sub-systems with complex nonlinear feedbacks and forcings. The possibility of synchronization between climate oscillations (global or local) and a predictable external forcing raises important questions of how models of such phenomena can be validated and verified, since the resulting response may be relatively insensitive to the details of the model being synchronized. The use of laboratory analogues may therefore have an important role to play in the study of natural systems that can only be observed and for which controlled experiments are impossible. We go on to demonstrate that synchronization can be observed in the laboratory, even in weakly coupled fluid dynamical systems that may serve as direct analogues of the behaviour of major components of the Earth's climate system. The potential implications and observability of these effects in the long-term climate variability of the Earth is further discussed. © 2010 Springer-Verlag Berlin Heidelberg.