Exact and Asymptotic Conditions on Traveling Wave Solutions of the Navier-Stokes Equations

We derive necessary conditions that traveling wave solutions of the Navier-Stokes equations must satisfy in the pipe, Couette, and channel flow geometries. Some conditions are exact and must hold for any traveling wave solution irrespective of the Reynolds number ($Re$). Other conditions are asymptotic in the limit $Re\to\infty$. The exact conditions are likely to be useful tools in the study of transitional structures. For the pipe flow geometry, we give computations up to $Re=100000$ showing the connection of our asymptotic conditions to critical layers that accompany vortex structures at high $Re$

Stable manifolds and homoclinic points near resonances in the restricted three-body problem

The restricted three-body problem describes the motion of a massless particle under the influence of two primaries of masses $1-\mu$ and $\mu$ that circle each other with period equal to $2\pi$. For small $\mu$, a resonant periodic motion of the massless particle in the rotating frame can be described by relatively prime integers $p$ and $q$, if its period around the heavier primary is approximately $2\pi p/q$, and by its approximate eccentricity $e$. We give a method for the formal development of the stable and unstable manifolds associated with these resonant motions. We prove the validity of this formal development and the existence of homoclinic points in the resonant region. In the study of the Kirkwood gaps in the asteroid belt, the separatrices of the averaged equations of the restricted three-body problem are commonly used to derive analytical approximations to the boundaries of the resonances. We use the unaveraged equations to find values of asteroid eccentricity below which these approximations will not hold for the Kirkwood gaps with $q/p$ equal to 2/1, 7/3, 5/2, 3/1, and 4/1. Another application is to the existence of asymmetric librations in the exterior resonances. We give values of asteroid eccentricity below which asymmetric librations will not exist for the 1/7, 1/6, 1/5, 1/4, 1/3, and 1/2 resonances for any $\mu$ however small. But if the eccentricity exceeds these thresholds, asymmetric librations will exist for $\mu$ small enough in the unaveraged restricted three-body problem

InterferenceAnalyzer: Tools for the analysis and simulation of multi-locus genetic data

BACKGROUND: Good statistical models for analyzing and simulating multilocus recombination data exist but are not accessible to many biologists because their use requires reasonably sophisticated mathematical and computational implementation. While some labs have direct access to statisticians or programmers competent to carry out such analyses, many labs do not. We have created a platform independent application with an easy-to-use graphical user interface that will carry out such analyses including the simulations needed to bootstrap confidence intervals for the parameters of interest. This software should make multi-locus techniques accessible to labs that previously relied on less powerful and potentially statistically confounded single interval or double interval techniques. RESULTS: We introduce InterferenceAnalyzer, an implementation with a user-friendly graphical interface incorporating previously developed algorithms for the analysis and simulation of multilocus recombination data. We demonstrate the use and features of the program with an example of multilocus tetrad data from the mustard plant, Arabidopsis thaliana, and the yeast, Saccharomyces cerevisiae. CONCLUSION: InterferenceAnalyzer provides easy access to the powerful and appropriate statistical tools for the multi-locus analysis of genetic data

Optimisation of Diesel Engine for Hybrid Military Tracked Vehicles using Matlab-Simulink

The demand in the technology requirements for diesel engines is growing keeping hybrid vehicles in mind. In future the diesel engine no longer drives the wheels directly; as a result the engine can be engaged at a limited number of operating points, thus, offering an opportunity to optimise the fuel efficiency and performance at those operating points. The extent to which this optimisation is possible is limited by practical considerations. Also if the positive and negative power peaks in vehicle during mobility (e.g. acceleration and regenerative braking respectively) can be accommodated by high-power batteries, then the size of the engine can be considerably reduced. The engine’s operating points depend on the power-control strategy. The consequences of modifications to these operating points will have an effect on performance and efficiency. As in series hybrid only a limited number of operating points are involved and dynamic performance requirements are not imposed on the diesel engine, significant improvements can be achieved by the optimisation of the diesel engine at these operating points. The feasibility of optimisation of the engine at these operating points can be done by modification on the injection systems, the valve timings and other such parameters. This kind of approach requires the use of complex and repeated experimental analysis of the engine which is costly, cumbersome and time consuming. An alternative to this kind of experimental approach is to develop a simulation model of the engine with the generator in Matlab- Simulink

Obstructive sleep apnea: Awakening the hidden truth

Obstructive sleep apnea (OSA) is a common type of sleep apnea and is caused by obstruction of upper airway. Sleep apnea is clinically defined as frequent episodes of apnea, hypopnea and symptoms of functional  impairment, which could be life.threatening and associated with extreme daytime hyper somnolence, dysfunction, discrements in health.related quality of life, automobile accidents, and cardiovascular morbidity and  mortality. Etiopathogenic factors that contribute to OSA include reduced upper.airway dilator muscle activity during sleep, upper.airway anatomical features, ventilatory control insufficiency, lung volume, and rostral fluid shifts. The presence of risk factors such as age, gender and obesity increases the incidence of OSA. The repetitive nocturnal hypoxemia  experienced by patients with OSA is associated with activation of a number of neural, humoral, thrombotic, metabolic, and inflammatory disease mechanisms, all of which have also been implicated in the pathophysiology of various systemic diseases. This article summarizes the etiopathogenesis, epidemiology, associated systemic diseases such as cardiovascular diseases, diabetes, and dental diseases with OSA and the influence of tongue on oropharyngeal airway in OSA patients. Key words: Apnea, breathlessness, snorin

Effectiveness of Resistance Training on the Strength of Scapulo-humeral Muscles and Abdominals in Male Volley Ball Players

Background: Volleyball is a sportive modality that requires strength in the upper and lower extremities along with the trunk musculature. The improvement of muscular strength is very important along with agility and flexibility for a volleyball player. Aim of the study to find the effectiveness of resistance training on the strength of scapulo-humeral muscles and abdominals in male volley ball players. Objectives of this study is find out the effect of resistance training on the strength of the scapulo-humeral muscles by measuring peak torque by using an isokinetic dynamometer and to find out the effect of resistance training on strength of abdominals through 1RM test. Methods: A group of 30 male volleyball players who have fulfilled the inclusion criteria were assigned into two groups control and experimental groups each consisting of 15 subjects. The subjects of the experimental group underwent resistance training under my supervision and the subjects of the control group done the same protocol unsupervised for 6 weeks. Results: There was significant improvement in the strength of scapula-humeral muscles and abdominals in the experimental group when compared to the control group when the pre and post intervention values were measured (p=0.05). Conclusion: Resistance training under supervision of the therapist resulted in significant improvement in strength of the scapulo-humeral muscles and abdominals in the male volleyball players

Designing Collaborative Systems to Enhance Team Performance

Collaborative technologies are widely used to enable teams to function effectively in today’s competitive business environment. However, prior research has been inconclusive regarding the impacts of collaborative technologies on team performance. To address the inconsistencies in prior work, this paper seeks to understand the mediational mechanisms that transmit the effect of collaborative technologies on team performance. Specifically, we theorize that there is a relationship between design features and knowledge contextualization. We further theorize relationships between knowledge contextualization and a team’s capability for collaboration, specifically examining collaboration know-how and absorptive capacity, both of which are expected to influence team performance. We conduct a field study including 190 software project teams from a large organization in China. The results support our theoretical model and demonstrate that design features have an impact on performance outcomes, mediated by collaboration know-how and absorptive capacity