Vänner, kolleger och gynnare : Namngivningen av de finska fästningsverken under Augustin Ehrensvärds tid

Under 1700-talets andra hälft hörde Sveriges nya fästningar i öst (Helsingfors, Sveaborg, Lovisa och Svartholm) till rikets största satsningar. Fästningsprojektet leddes med undantag av ett par avbrott av Augustin Ehrensvärd (1710 1772). När arbetet tog fart namngavs de enskilda fästningsverken i så gott som alla fall efter samtida personer. Under Ehrensvärds tid tillämpades denna namngivning på omkring femtio av Sveaborgs och Helsingfors fästningsverk samt på Lovisas och Svartholms totalt aderton verk. Genom personerna de knöts till berättar namnen en hel del om Augustin Ehrensvärds samtid och omvärld. Hur de gjorde det är denna avhandlings huvudfråga. Källmaterialet utgörs av relationsritningar och brev, medan de teoretiska ramarna står att finna i nätverksteori och onomastiska teorier om namnmönster. Ehrensvärd förklarade sin namngivningspraxis för sin överordnade, tronföljaren Adolf Fredrik, 1749 i samband med att Gustavssvärd med fästningsverk namngavs: tanken var att namnge bastioner efter de som bidragit till arbetets framgång och att namnge utanverk efter officerare vid fästningsbygget. Innebörden av Ehrensvärds ord framgår ur namnbeståndet. De största grupperna består av ämbetsmän och militärer. Med de som bidragit till arbetets framgång avsågs sålunda den lokala eliten: landshövdingar som involverats i fästningsbygget samt högre och lägre militärer som tjänstgjorde vid fästningarna. Redan från början syns en klar hierarki i namngivningen. Medan landshövdingarna och de högre militärerna tillägnades bastioner, fick de lägre officerarna se mindre fästningsverk namngivna efter sig, helt i enlighet med Ehrensvärds egen beskrivning. Utanför de ovan nämnda grupperna, hedrades en hel del personer som inte konkret hade engagerats i fästningsbygget. Denna namngivning kan förklaras å ena sidan inom ramen för Ehrensvärds sociala nätverk och å andra sidan mot bakgrund av riksdagspolitiken i frihetstidens Sverige. Av de två förklaringsmodeller bör Ehrensvärds personliga vänskaper ses som en bidragande orsak, medan de politiska motiven utgjorde en avgörande orsak. Som en del av Ehrensvärds nätverk kan de gynnare ses som hade stöttat Ehrensvärd under hans karriär samt hans närmaste medarbetare vid fästningsbygget, ofta officerer han själv handplockat. Namngivningens politiska aspekt syns i det stora antalet riksråd som tillägandes bastionnamn. Vid sidan om riksråden hedrades också talmän vid de samtida riksdagarna. En komparativ studie i namngivningen av fästningsverk vid samtida och äldre svenska fästningar framhäver Ehrensvärd som en innovativ namngivare. Fästningsverk namngivna efter kungligheter verkar ha varit en norm, som också Ehrensvärd anknöt till genom ett fåtal namn. Däremot var namn efter personer inte vanliga, vilket gav den Ehrensvärdska namngivningen en förhållandevis stark anknytning till samtiden. Denna aspekt bekräftas om namnen ses mot bakgrund av 1700-talets uppfattning om ära och äregirighetens samhälleliga nytta. I denna uppfattning syns bakgrunden till förekomsten av personer med både hög och låg status i Ehrensvärds namngivning. Sammanfattningsvis speglar namnen på de finska fästningsverken sin samtid genom den byråkratiska, militära och politiska elit de representerar samt genom motiveringen till dem.

Analysis of grid connected induction generators driven by hydro/wind turbines under realistic system constraints

Results of an investigation dealing with the behaviour of grid-connected induction generators (GCIGs) driven by typical prime movers such as mini-hydro/wind turbines are presented. Certain practical operational problems of such systems are identified. Analytical techniques are developed to study the behavior of such systems. The system consists of the induction generator (IG) feeding a 11 kV grid through a step-up transformer and a transmission line. Terminal capacitors to compensate for the lagging VAr are included in the study. Computer simulation was carried out to predict the system performance at the given input power from the turbine. Effects of variations in grid voltage, frequency, input power, and terminal capacitance on the machine and system performance are studied. An analysis of self-excitation conditions on disconnection of supply was carried out. The behavior of a 220 kW hydel system and 55/11 kW and 22 kW wind driven system corresponding to actual field conditions is discussed

Bioleaching of sulphides under applied potentials

The influence of applied DC potentials on the activity and growth of Thiobacillus ferrooxidans, as well as on the dissolution behaviour of some base metal sulphides is discussed with reference to bioleaching. Selective bioleaching of zinc from sphalerite could be achieved under an applied potential of −500 mV (saturated calomel electrode) from binary mineral mixtures containing the zinc mineral and chalcopyrite or pyrite. On the other hand, bioleaching of pyrite and chalcopyrite was found to be enhanced under positive potentials of +400 mV and +600 mV, respectively. Probable mechanisms in the electrobioleaching of sulphides are examined with respect to galvanic, microbiological and applied potential effects.

Dislocation characterization in crystals of potash alum grown by seeded solution growth under conditions of low supersaturation

An analysis has been carried out of the genesis and character of growth dislocations present in all growth sectors of single crystals of potash alum. The crystals, grown from seeded solutions by the temperature lowering method under conditions of low supersaturation, presented the well-developed forms: {111} dominant, {100} and {110}. Growth dislocations formed predominately during refacetting of the edges and corners of the seed, rounded during preparation and insertion into the supersaturated solution. From here they become refracted into the {111} sectors which proved to be the most defective. Smaller numbers of dislocations form at the {111}, {100} and {110} seed interfaces and propagate in these sectors. In crystals of inferior quality, a number of inclusions were found predominantly in the fast growing {100} sectors which become the source of additional dislocations. Dislocations present in the original seed did not propagate across the interface into the developing crystal. Dislocations of all characters were observed. The principal Burgers vectors were found to be left angle bracket100right-pointing angle bracket, left angle bracket110right-pointing angle bracket and left angle bracket111right-pointing angle bracket.

2-Dimensional Linear-Stability of Premixed Laminar Flames Under Zero-Gravity

This paper reports on the numerical study of the linear stability of laminar premixed flames under zero gravity. The study specifically addresses the dependence of stability on finite rate chemistry with low activation energy and variable thermodynamic and transport properties. The calculations show that activation energy and details of chemistry play a minor role in altering the linear neutral stability results from asymptotic analysis. Variable specific heat makes a marginal change to the stability. Variable transport properties on the other hand tend to substantially enhance the stability from critical wave number of about 0.5 to 0.20. Also, it appears that the effects of variable properties tend to nullify the effects of non-unity Lewis number. When the Lewis number of a single species is different from unity, as will happen in a hydrogen-air premixed flame, the stability results remain close to that of unity Lewis number.

Out-of-equilibrium microrheology using optical tweezers to probe directional viscoelastic properties under shear

Many wormlike micellar systems exhibit appreciable shear thinning due to shear-induced alignment. As the micelles get aligned introducing directionality in the system, the viscoelastic properties are no longer expected to be isotropic. An optical-tweezers-based active microrheology technique enables us to probe the out-of-equilibrium rheological properties of a wormlike micellar system simultaneously along two orthogonal directions-parallel to the applied shear, as well as perpendicular to it. While the displacements of a trapped bead in response to active drag force carry signature of conventional shear thinning, its spontaneous position fluctuations along the perpendicular direction manifest an orthogonal shear thickening, an effect hitherto unobserved. Copyright (C) EPLA, 2010

Dynamic response of a beam on elastic foundation of finite depth under a moving force

In this paper, dynamic response of an infinitely long beam resting on a foundation of finite depth, under a moving force is studied. The effect of foundation inertia is included in the analysis by modelling the foundation as a series of closely spaced axially vibrating rods of finite depth, fixed at the bottom and connected to the beam at the top. Viscous damping in the beam and foundation is included in the analysis. Steady state response of the beam-foundation system is obtained. Detailed numerical results are presented to study the effect of various parameters such as foundation mass, velocity of the moving load, damping and axial force on the beam. It is shown that foundation inertia can considerably reduce the critical velocity and can also amplify the beam response.

Microstructural features of flow instability in α-titanium cylinders under high strain rate compression at 25°C to 400°C

Cylindrical specimens of commercial pure titanium have been compressed at strain rates in the range of 0.1 to 100 s-1 and temperatures in the range of 25-degrees-C to 400-degrees-C. At strain rates of 10 and 100 s-1, the specimens exhibited adiabatic shear bands. At lower strain rates, the material deformed in an inhomogeneous fashion. These material-related instabilities are examined in the light of the ''phenomenological model'' and the ''dynamic materials mode.'' It is found that the regime of adiabatic shear band formation is predicted by the phenomenological model, while the dynamic materials model is able to predict the inhomogeneous deformation zone. The criterion based on power partitioning is competent to predict the variations within the inhomogeneous deformation zone.

Simultaneous heat and mass transfer under unsteady mixed convection along a vertical slender cylinder embedded in a porous medium

Unsteady laminar mixed convection flow (combined free and forced convection flow) along a vertical slender cylinder embedded in a porous medium under the combined buoyancy effect of thermal and species diffusion has been studied. The effect of the permeability of the medium as well as the magnetic field has been included in the analysis. The partial differential equations with three independent variables governing the flow have been solved numerically using a implicit finite difference scheme in combination with the quasilinearization technique. Computations have been carried out for accelerating, decelerating and oscillatory free stream velocity distributions. The effects of the permeability of the medium, buoyancy forces, transverse curvature and magnetic field on skin friction, heat transfer and mass transfer have been studied. It is found that the effect of free stream velocity distribution is more pronounced on the skin friction than on the heat and mass transfer. The permeability and magnetic parameters increase the skin friction, but reduce the heat and mass transfer. The skin friction, heat transfer and mass transfer are enhanced due to the buoyancy forces and curvature parameter. The heat transfer is strongly dependent on the viscous dissipation parameter and the Prandtl number, and the mass transfer on the Schmidt number. Untersucht wurde die instationäre laminare Mischkonvektion längs eines vertikalen, in einem porösen Medium eingebetteten Zylinders unter kombinierten Auftriebseffekten von thermischer und spezieller Diffusion. Der Einfluß der Permeabilität des Mediums sowie des magnetischen Feldes wurden in die Betrachtung einbezogen. Die partiellen Differentialgleichungen mit drei unabhängigen Variablen, welche die Strömung beschreiben, wurde numerisch anhand des Schemas der endlichen Differenzen in Verbindung mit der Technik der Quasilinearisation gelöst. Berechnungen für die beschleunigte, verzögerte und oszillierende Geschwindigkeitsverteilung der freien Strömung sind durchgeführt worden. Untersucht wurden ebenfalls die Effekte der Permeabilität des Mediums, der Auftriebskräfte, der transversalen Krümmung, des magnetischen Feldes auf die Oberflächenreibung sowie die Wärmeund Stoffübertragung. Es wurde festgestellt, daß die Geschwindigkeit mehr Einfluß auf die Oberflächenreibung als auf die Wärmeund Stoffübertragung hat. Die Oberflächenreibung sowie die Wärme- und Stoffübertragung werden durch die Auftriebskräfte und die Krümmungsparameter verbessert. Die Wärmeübertragung ist stark abhängig von den Parametern der viskosen Dissipation und der Prandtl-Zahl; die Stoffübertragung von der Schmidt-Zahl.