Sökning: "initial time"

Visar resultat 1 - 5 av 1641 avhandlingar innehållade orden initial time.

1. 1. Tid till förfogande : Förändrad användning och fördelning av undervisningstid i grundskolans senare år?

   Författare :Mikaela Nyroos; Lisbeth Lundahl; Anders Lidström; Mikael Alexandersson; Umeå universitet; []
   Nyckelord :SAMHÄLLSVETENSKAP; SOCIAL SCIENCES; School autonomy; time allocation; time use; pupil influence; pupil individualisation; teacher work; change.; Pedgogical work; Pedagogiskt arbete;

   Sammanfattning : The Swedish education system has undergone decentralisation and deregulation since the late 1970s. The 1999 parliamentary resolution for a 5-year experiment of increased school autonomy in time allocation, was a late step in this development. LÄS MER

3. 2. Strong Cosmic Censorship and Cosmic No-Hair in spacetimes with symmetries

   Författare :Katharina Maria Radermacher; Hans Ringström; James Isenberg; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Cosmic Censorship; Cosmic No-Hair; Big Bang; symmetry; Bianchi; T2-symmetry; Gowdy; general relativity; cosmology; late time; initial time; asymptotic behaviour; perfect fluid; scalar field; Einstein equations; Mathematics; Matematik;

   Sammanfattning : This thesis consists of three articles investigating the asymptotic behaviour of cosmological spacetimes with symmetries arising in Mathematical General Relativity.In Paper A and B, we consider spacetimes with Bianchi symmetry and where the matter model is that of a perfect fluid. LÄS MER

4. 3. High order summation-by-parts methods in time and space

   Författare :Tomas Lundquist; Jan Nordström; Peter Eliasson; David A. Kopriva; Linköpings universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; summation-by-parts; time integration; stiff problems; weak initial conditions; high order methods; simultaneous-approximation-term; finite difference; discontinuous Galerkin; spectral methods; conservation; energy stability; complex geometries; non-conforming grid interfaces; interpolation;

   Sammanfattning : This thesis develops the methodology for solving initial boundary value problems with the use of summation-by-parts discretizations. The combination of high orders of accuracy and a systematic approach to construct provably stable boundary and interface procedures makes this methodology especially suitable for scientific computations with high demands on efficiency and robustness. LÄS MER

5. 4. LQG-Based Real-Time Scheduling and Control Codesign

   Författare :Yang Xu; Institutionen för reglerteknik; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; LQG control; Real-time system; Scheduling; Time-delay system;

   Sammanfattning : Having multiple control tasks concurrently running on a single computing platform increases the processor utilization but degrades the control performance due to delay and jitter. In scheduling and control codesign, the objective is to optimize the combined performance of all the controllers, subject to a schedulability constraint. LÄS MER

7. 5. Runge-Kutta Solution of Initial Value Problems: Methods, Algorithms and Implementation

   Författare :Hans Olsson; Institutionen för datavetenskap; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Computer science; stiffness; software; computational process; differential algebraic equations; ordinary differential equations; Runge-Kutta; initial value problems; time-stepping; system; kontroll; numerisk analys; Datalogi; control; numerical analysis; systems;

   Sammanfattning : The last decades have seen a strongly increasing use of computers for modeling larger and more complex systems. This has been made possible by a combination of increasing computer power and easy-to-use graphical modeling environments and libraries of components. LÄS MER