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An unsteady mixed free convection MHD flow of elastic-viscous incompressible fluid past an infinite vertical porous flat plate is investigated when the presence of heat Source/sink, temperature and concentration are assumed to be oscillating with time and hall effect. The governing equations are solved by complex variable technique. The expressions for the velocity field, temperature field and species concentration are demonstrated in graphs. The effects of the Prandtl number, the Grashof number, modified Grashof number, the Schimidt number, the Hall parameter, Elastic parameter & Magnetic parameter are discussed., {"references":["","N. Datta, R. N. Jana, Oscillatory magnetohydrodynamic flow past a flat plate will Hall effects, J. Phys. Soc.Japan, 40, 1469, 1976.","S. Biswal, P. K. Sahoo, Hall effect on oscillatory hydromagnetic free convective flow of a visco-elastic fluid past an infinite vertical porous flat plate with mass transfer, Proc. Nat. Acad. Sci., 69A, 46, 1994.","M. Acharya, G.C. Dash and L.P Singh, \"Hall effect with simultaneous thermal and mass diffusion on unsteady hydromagnetic flow near an accelerated vertical plate,\" Ind. J. Physics. B., 75B, 68-70(2001).","E. M. Aboeldahab and E.M.E. Elbarbary, \"Hall current effect magneto-hydrodynamics free convection past a semi-infinite vertical plate with mass transfer,\"Int. J. Engg. Sci., 39, 1641-1652 (2001).","N. Senapati, B. Jena and R. K. Dhal, mass and heat transfer effect on MHD oscillatory flow in a channel filled with porous medium, Orissa journal journal of physics,vol-17(1),2010.","S. Abel & P. H. Veena, \"Visco-Elastic Fluid Flow and Heat Transfer in porous medium over a stretching street'', International Journal of Non-linear Mechanics vol.33,1998,pp.531-540.","H. I. Andersson. \"MHD Flow of visco-Elastic Fluid past a stretching surface,\" Acta Mechanica, vol.95,1992, pp.227-230.","S. Abel, A. Soshi and R. M. Sonth, \"Heat Transfer in a MHD Visco-Elastic Fluid over a stretching surface\", Journal of Applied Mathematics and Mechanics,vol.81,2001,pp.691-698.","S. Abel, P. H. Veena, K. Rajgopal and V. K. Pravin, \"Non-Newtonian Magneto hydrodynamic Flow over a stretching surface with Heat & Mass Transfer\", International journal of Non-linear Mechanics,vol.39, 2004,pp.1067-1078. \n[10] M.A.Sheddeek,\"Heat and Mass Transfer on a stretching sheet with a magnetic field in a Visco-Elastic fluid flow through a porous medium with heat source or sink\", Computational Materials science, vol.38, 2007, pp.781-787. \n[11] S. Abel and N. Mahesha,\" Heat Transfer in MHD Visco-Elastic fluid flow over a stretching sheet with variable Thermal conductivity, Non-unifrom Heat source and Radiation\", Applied Mathematical modelling,vol.32,2008,pp.1965-1983.\n[12] K. V. Prasad, D. Pal, V. Umesh and N. S. Prasanna Rao, \"The Effect of variable viscosity on MHD Visco-Elastic fluid flow and Heat transfer over a stretching sheet,\" Communi-cations in Non-linear science and Numerical Simulation, vol.15, No.2, February 2010, pp.331-344. \n[13] K. R. Rajgopal, T. Y. Na & A. S. Gupta,” Flow of visco-elastic fluid over a stretching sheet”, Rheol Acta,vol.23,1984,pp.213-215. "]}

When a liquid is quenched sufficiently rapidly below its solidification temperature, a disordered and out-of-equilibrium solid called glass may be formed instead of the crystal, after a stark slowing down of the dynamics. This glass transition is wide spread but a sound explanation, lying on solid grounds, of the slowing down of the dynamics remains elusive. Colloidal suspensions exhibit such a transition as the particle volume fraction increases rapidly. In this thesis, an experimental study of the dynamics of colloidal suspensions of thermosensitive microgels is performed as the glass transition approaches and beyond. The diameter of these soft spheres depends on the bath temperature, which enables to reversibly tune the volume fraction of the suspension and thus to study the glass transition continuously on a single sample. First, the dynamic heterogeneities which grow simultaneously to the slowing down of the dynamics, and play a major role in the theories trying to explain the glass transition, are studied using video microscopy particle tracking. On short time scales a purely spatial heterogeneity of the dynamics is found to develop. Slow and rapid domains of homogeneous dynamics coexist in the suspension, the amplitude of the differences in dynamics is found to increase as the glass transition approaches. The spatial extent of the homogeneous domains is then measured using image correlation, which is found to grow when approaching the glass transition. Finally, a method for probing the three dimensional rotational Brownian motion of micrometric wires is developed and applied to measuring the microrheological properties of complex fluids and then to the comparison of fluctuations and dissipation function, measured through the rotational response of the superparamagnetic wires to oscillating magnetic fields, in model fluids and then in glassy suspensions., Quand un liquide est refroidi suffisamment rapidement en dessous de sa température de solidification, il peut se former à la place du cristal un solide désordonné et hors équilibre appelé verre, après un ralentissement brutal de la dynamique du liquide. Cette transition vitreuse est très largement répandue, mais la cause du ralentissement reste pour une grande part mal comprise. Les suspensions colloïdales présentent une telle transition quand la fraction volumique en particules croît. Dans cette thèse, la dynamique de suspensions colloïdales de microgels thermosensibles est étudiée expérimentalement à l'approche de la transition vitreuse et au delà. Le diamètre de ces sphères molles dépend de la température du bain, ce qui permet de moduler de façon réversible la fraction volumique et d'étudier ainsi la transition vitreuse continument sur un seul et même échantillon. Dans un premier temps les hétérogénéités de la dynamique qui se développent simultanément au ralentissement de la dynamique, et jouent un rôle théorique majeur dans les tentatives d'explication de la transition vitreuse, sont étudiées en vidéo-microscopie. Sur des temps courts, une hétérogénéité purement spatiale de la dynamique est mise en évidence. Des zones lentes et rapides de dynamique homogène coexistent dans l'échantillon, l'amplitude des variations entre zones croissant à l'approche de la transition et restent grandes dans le verre. Dans un second temps, l'extension spatiale de ces zones homogènes est mesurée en corrélation d'image, et trouvée croissante à l'approche de la transition. Enfin, une méthode de mesure du mouvement brownien rotationnel en trois dimensions d'aiguilles micrométriques est développée et appliquée à la mesure des propriétés microrhéologiques de fluides complexes puis à la comparaison entre fluctuations et fonction de dissipation, mesurée grâce à la réponse des aiguilles superparamagnétiques à des champs magnétiques oscillants, dans des fluides modèles puis dans des suspensions vitreuses.

Increasing baseball bat velocity is the goal of many baseball strength and conditioning programs, as fast bat velocity is essential for successfully hitting a baseball. Despite the desire to increase bat velocity, few studies have examined the effectiveness of training using rotational and linear plyometric exercises in baseball batting specific motions. This study investigates the effects of a combination rotational and linear plyometric program on baseball bat swing velocity. Participants consisted of healthy male NCAA Division I baseball hitters. Twelve participants were randomly assigned to one of two groups, an experimental and a control group. All participants performed standard off-season baseball practice and weight training. The experimental group also completed a rotational and linear plyometric exercise program two times per week for 8 weeks, while the control group had no intervention. Bat velocity was assessed prior to training, after 4 weeks of training, and after 8 weeks of training. A 2x3 mixed factorial repeated measures design was used to investigate the effects of the rotational and linear training program on bat velocity. Significance was set at alpha < 0.05. No significant main group effect, time effect, or time and group effect was found. However practical significance was found, as the plyometric training group had a 9.5% improvement in bat velocity and the control group had a 1.7% improvement in bat velocity at the end of the study. Therefore, the use of normal practice and weight training, and a combination rotational and linear plyometric program had no significant effect on baseball bat velocity, but did account for some positive increases. This study serves as a starting point for further research needed to improve bat velocity in Division I College baseball players.

In dieser Arbeit wird eine neue Methode der Kurzzeitspektroskopie vorgestellt, welche die Messung korrelierter Eigenschaften von Molekülen in der Gasphase erlaubt. Die korrelierte Rotationsausrichtungsspektroskopie (engl.: correlated rotational alignment spectroscopy - kurz: CRASY) kombiniert hochaufgelöste Rotationsspektroskopie mit zeitaufgelöster Femtosekundenspektroskopie und ermöglicht strukturelle Informationen über den molekularen Grundzustand mit den Observablen der Femtosekundenspektroskopie zu verknüpfen. Erste CRASY- Experimente wurden an Schwefelkohlenstoff durchgeführt, ein lineares Molekül mit hoher Anisotropie der Polarisierbarkeit. Diese Anisotropie erlaubt die Erzeugung eines Rotationswellenpaketes im molekularen Grundzustand über stimulierte Raman-Anregung von Rotationsniveaus mit einem ultrakurzen, linear polarisierten Laserimpuls. Die kohärente Rotationsbewegung der Moleküle lässt sich mit einem zeitverzögerten Femtosekundenlaserimpuls beobachten. Dieser zweite linear polarisierte Laserimpuls regt resonant elektronische Zustände an und bildet so die Rotationsbewegung eines molekularen Ensembles auf angeregte elektronische Zustände ab. Die Anregung resonanter elektronischer Zustände ist gleichzeitig das verknüpfende Element zu einem darauffolgenden Femtosekundenexperiment. Die orientierungsabhängige resonanzverstärkte Ionisation der Schwefelkohlenstoffmoleküle als Funktion der Verzögerungszeit zwischen beiden Laserimpulsen bildet die Rotationsbewegung auf ionische Zustände ab. Aus den rotationsmodulierten Ionenmassesignalen (Massen-CRASY) lassen sich durch Fourieranalyse massenselektive Raman-Rotationsspektren ermitteln, welche strukturelle Informationen über die schwingungslosen elektronischen Grundzustände der Moleküle dieser Masse tragen. Zudem können Ionenmassen über charakteristische Raman-Rotationsübergangsfrequenzen gefiltert werden um so strukturselektive Massenspektren zu generieren. Eine einzige CRASY-Messungen an einer Schwefelkohlenstoffprobe mit natürlichem Isotopenverhältnis erlaubte die Identifikation von 10 stabilen Schwefelkohlenstoffisotopologen und die Bestimmung der zugehörigen Rotationskonstanten. Mit CRASY konnten so drei bislang nicht dokumentierte Rotationskonstanten bestimmt werden, ohne teure isotopenangereicherte Proben zu benutzen. Anhand eines Elektronen-CRASY Experimentes an Schwefelkohlenstoff wird gezeigt, dass die Korrelation von Photoelektronen- und Raman- Rotationsspektren möglich ist. Dieses Experiment erlaubt strukturselektive Elektronenspektren zu messen. Über die gemeinsamen Strukturinformationen lassen sich zudem Elektronenspektren mit Ionenmassen korrelieren. CRASY Experimente werden in Zukunft eine große Rolle bei der Untersuchung strukturell komplexer und inhomogener Proben spielen, welche mit traditionellen spektroskopischen Methoden nicht zugänglich sind. Um zu zeigen, dass CRASY-Experimente auch mit strukturell komplexeren Molekülen mit weniger günstigen Raman-Anregungsquerschnitten möglich sind, wurden Massen-CRASY Experimente an Butadien durchgeführt., This thesis presents a new method in ultrafast spectroscopy, which allows to measure correlated molecular properties in gas phase experiments. Correlated Rotational Alignment Spectroscopy (CRASY) connects high-resolution rotational spectroscopy with time-resolved femtosecond spectroscopy and thereby links observables of ultrafast spectroscopy to structural molecular properties. CRASY experiments create rotational wave packets by stimulated Raman-- excitation of rotational energy levels in the molecular ground state, using short linearly polarised laser pulses. The coherent rotational motion is projected onto excited states by delayed femtosecond laser pulses, which resonantly excite the molecules. The observation of rotational motion via an electronic excitation process links rotational spectroscopy in the time-domain to a subsequent femtosecond experiment. An additional photon can ionise the excited molecules. The yield of electrons and ions formed by resonance enhanced two--photon ionisation is modulated by the rotational motion of the molecules and varies as function of time delay between alignment and ionisation pulse. Fourier analysis of time traces extracts rotational Raman spectra for each detected species contributing to a specific ion or electron signal. An analysis of ions in a mass spectrometer (mass-CRASY) therefore allows to extract mass-selected rotational Raman spectra, which contain structural information about the molecular vibrational and electronic ground state before photoexcitation. Ion mass signals can also be filtered by Raman transition frequencies to show photochemical products of a structure-selected species. A single mass-CRASY measurement of natural occurring carbon disulfide allowed to derive rotational constants for 10 stable carbon disulfid isotopologues with abundances down to 10^(-6). Multiple atomic and molecular fragments formed in the ionisation process were assigned to a distinct parent- molecule. A mass--CRASY experiment of trans-1,3-butadiene revealed the predominant loss of outer carbon atoms and showed that isotopic scrambling before CH3 loss plays a minor role in the predominant fragmentation channel of the butadiene cation. The observation of electron signals allows to correlate electronic spectra with rotational Raman spectra (electron-CRASY) and therefore links the electronic structure to the ground state geometry of a molecule. Additionally, ion masses and electron energies can be correlated via their rotational Raman spectra. Mass-CRASY and electron-CRASY experiments of carbon disulfide demonstrate the correlation of ions and electrons for the two most abundant isotopologues of carbon disulfide. CRASY therefore obviates the need for time-consuming coincidence experiments. In the future, we expect CRASY experiments to play an important role in characterising complex and inhomogeneous samples, which are inaccessible by traditional spectroscopic methods.

Objectives A diagnosis of ‘positional’ vertebrobasilar ischaemia is considered in patients presenting with dizziness/vertigo during lateral neck rotation/extension and is attributed to bony ‘nipping’ of the vertebral artery (VA). This study reviewed our experience with extracranial and transcranial ultrasound to determine whether a diagnosis of ‘positional’ vertebrobasilar ischaemia was associated with any changes in flow in the extracranial VA and the P1 segment of the posterior cerebral artery (PCA) during head turning. Methods A retrospective case note review was undertaken in 46 patients with an accessible window for transcranial Doppler who had undergone extracranial and transcranial assessment of flow velocity and flow directionality in the VA and PCA while the head was moved into positions that normally triggered the patient's symptoms. Results Positional ‘vertebrobasilar symptoms’ were triggered by lateral head rotation in 35 patients (76%), while 11 (24%) developed symptoms following neck extension. Only one patient was found to have a significant carotid stenosis (symptoms unchanged following carotid endarterectomy) and none had significant disease in the extracranial VAs. None of the patients exhibited any change in extracranial VA flow during head turning/extension and none had reversal of flow either. Similarly, there was no change observed in the PCA flow characteristics during head turning. The majority of patients (74%) were subsequently referred to the Ear, Nose and Throat (ENT) department, and 94% of the patients noted an improvement in symptoms following entry into a vestibular rehabilitation programme. Conclusions A diagnosis of ‘positional’ vertebrobasilar ischaemia should be made with extreme caution and only after a specialist assessment in a Balance Centre.

Permanent grass overgrowth holds a great importance in the Czech Republic's agriculture. It's functions in the landscape are mostly anti-erosive and landscape-creating. In comparison to other European countries, the ploughed area in the Czech Republic is larger. Therefore it is possible to expect an increase in the overall dimension of the ploughed area, which brings a necessity of land management. An insufficient level of used pratotechnical actions can cause a shift in the effects of grazing on the environment - from the positive to the negative. An excessive straining of herbage linked to the absence of needed interventions leads to a degradation of physical and chemical attributes of the soil. The problem that appears the most is treading out the grass sod, compacting the soil and beginning of the erosive processes. Overlooking this serious frame leads to total devaluation of the land. Therefore adopting and consistent keeping of comprehensive collection of pratotechnical actions, that lead to gradual make up and elimination of the negative effects of the grazing on the land, is vital. This thesis deals with processing the collection of pratotechnical actions, on the basis of realized links between the type of grazing system and evaluated physical and chemical parameters of soils, in two-model areas {--} grazing area Ostřice and grazing area Jenín-Babín.

At present the mountains and sub mountains areas of grazing systems divided into two basic groups on a continuous and rotational. This issue is becoming increasinhgly important, especially with shift cattle with non-market production of milk, where pasture, as mowing and grazing, in particular, is a limits factor for sustainable agriculture in these areas. At present, increasing pressure to streamline the production of nutritionally valueble forage for healty nutrition of cattle in ecological environment by minimalisation energetic and financial inputs. Important role here, among other things, taking the physical properties of soils, both from the aspects of production and in terms of species composition (eg increased incidence of lower secondary grass field of the excessive burden on pasture), influence of nutrition and quality of crop due to deterioration in porosity, volume weight, minimum gauziness etc. Degraded physical properties of soil for pasture crops directly threaten the basic elements of the environment, especiallly water quality.

Acoustic function plays an important role in aerodynamic mechanical engineering. It can classify the kind of air-vehicle such as subsonic or supersonic. Acoustic velocity relates with velocity and Mach number. Mach number relates again acoustic stability or instability condition. Mach number plays an important role in growth or decay in energy system. Acoustic is a function of temperature and temperature is directly proportional to pressure. If we control the pressure, we can control acoustic function. To get pressure stability condition, we apply Navier-Stokes equations., {"references":["Chong Zhou and Joseph Majdalani, \"Improved Mean-Flow Solution\nfor Slab Rocket Motor with Regressing Walls\", (AIAA paper 2000-\n3191).","Jonathan C. French, \"A Comparison of Nonlinear Combustion\nStability Mothods|\".","Flandro, G. A., and Majdalani, J., \"Aeroacoustic Instability in\nRockets,\" AIAA Journal, Vol. 41, No. 3, 2003, pp. 485-497.","Gary A. Flandro, \"Aero-acoustic Instability in Rockets\",AIAA\nJournal Vol.41, No.3, March, 2003.","Jonathan French, \"Improvements to the Linear Standard Stability\nPrediction Program (SSP)\", (AIAA paper 2004-4181).","Joseph M. Power, \"Gas Dynamic,\" Aerodynamic II, Lecture Notes,\nDepartment of Aerospace and Mechanical Engineering ,University of\nNorth Dame 2003.","Sean R. Fischbach, Joseph Majdalani, and Gary A. Flandro, \"Volume\nto Surface Transformation of Rocket Stability Integrals\", (AIAA\npaper 2004-4053).","Sean R. Fischbach, Joseph Majdalani, and Gary A. Flandro, \"Acoustic\nInstability and Slab Rocket Motor\", (AIAA paper 2004-4061).","Sean R. Fischbach, Joseph Majdalani, and Gary A. Flandro,\n\"Verification and Validation of Rocket Stability Integral\nTransformation\", (AIAA paper 2005-4001).\n[10] S.M. Yahya, \"Fundamental of Compressible Flow\", May 2003, Third\nEdition.\n[11] Weidong Cai and V. Yang, \"Turbulent Transport in Rocket Motor\nUnsteady Flow field,\" Vol.185, Progress in Astronautics and\nAeronautic, 2000, pp-837-858.\n[12] Yi Wang and Arnaud Trouve, \"Artificial Acoustic Stiffness\nReduction in fully Compressible, Direct Numerical Simulation of\nCombustion\"."]}

The subject of this thesis centers around the study of process; the process of taking a germinal concept or idea and translating it into the language of built form. In this particular case, the process can be described as binary, containing two distinct stages. The first stage consists of the process of translating a gestural idea or sketch into a language which is geometrically descriptive and consequently reproducible. The second stage of the process involves the translation of geometrical ideas into the language of construction. How can the dimensionless character of a geometrical model be expressed and accommodated architecturally? Master of Architecture

The objective was to study the effects of ethanol on coagulation and fibrinolysis in whole blood. Blood samples from healthy volunteers were analyzed before and after in-vitro addition of ethanol in order to achieve ethanol concentrations of 0, 1, 2 and 4[per mille sign], respectively (0, 22, 44 and 88 mmol/l). Coagulation and fibrinolysis were then assessed using rotational thromboelastometry. We found that increasing ethanol levels increasingly impaired coagulation as evaluated with rotational thromboelastometry, with a maximum prolongation of the clot formation time of 118% at an ethanol level of 4[per mille sign] (P < 0.000001). We also found a very strong impairment of fibrinolysis already at an ethanol level of 1[per mille sign]. This is the first study assessing the effects of ethanol on coagulation and fibrinolysis in a whole blood model. The impairment of coagulation is similar in nature to the impairment found in patients suffering from hypothermia. The impairment is at a level that may be of clinical importance (e.g. in patients suffering from trauma). The inhibition of fibrinolysis is obvious already at an ethanol level of 1[per mille sign] and it may be a contributing factor to the increased amount of coronary and cerebrovascular ischemic events after binge drinking.

The taming of electricity and its widespread use allows people to see in the dark, to speak to one another instantaneously across the earth, and it allows retrieval of data from instruments sent out of the solar system. It is right to expect that the uses and demand for electricity will continue to grow, and to extend the ability to generate electricity; here two new micromachined devices for converting mechanical energy into electrical energy are presented. Aided by the wealth of micromachining process technology, generators that use an oscillatory motion to modify the physical structure of a capacitor with a built-in electric field provided by a permanent electret have been designed, built, and tested. The electret creates an electric field inside the capacitor structure, which induces mirror charge at some potential. The modification of the capacitor then generates an alternating displacement current through an external circuit, which provides useful electrical power. The electret microphone is a similar well known device for converting pressure waves into electrical signals by varying the distance between two charged capacitive plates. This work explores and proves feasible the ability to use mechanical forces to change the overlapping area of a charged capacitor structure and using mechanical forces to move a liquid into the gap of a charged capacitor structure, changing its permittivity to produce electricity. This work demonstrates 2.5mW of power from a 2cm diameter rotary generator at 12kRPM and 10[micro]w for a 0.1cm3 linear shaking generator at 60Hz.

Mechanical vibration of a HDD can cause head mis-positioning. This effect can be compensated by using the device presented in the following. It is a capacitive rotational accelerometer sensor which uses MEMS. The vibrations of the disk drive cause tiny rotational displacements of the moving part of the MEMS structure, which are measured by sensing the small variations in capacitance that they cause. Capacitance changes as small as 0.05 fF can be measured by the device. The device operates as follows: the minute rotational vibrations are detected and measured in order to generate a feed-forward correction signal for the voice coil drive circuit to keep the head in the correct position. This allows the track spacing to be reduced significantly, increasing the storage density per unit area. The circuit has been realized in a 0.61 /spl mu/m BiCMOS technology with an area of 9.5 mm/sup 2/. The power consumption is 150 mW from a single 5V supply.

Coherent anti-Stokes Raman scattering was used to measure nitrogen single-pulse spectra at the entrance and exit area of a thrust nozzle. Thermodynamic nonequilibrium effects were proved at the exit of the hypersonic nozzle, belonging to an air-breathing, hydrogen-combusting ramjet model. To determine the accurracy of extracted rotational and vibrational temperatures, additional laboratory experiments were performed. The nozzle expansion was characterized by wall pressure measurements