Sökning: "multistage"

Visar resultat 11 - 15 av 69 avhandlingar innehållade ordet multistage.

1. 11. Design and analysis of response selective samples in observational studies

   Författare :Maria Grünewald; Ola Hössjer; Keith Humphreys; Marie Reilly; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; ascertainment; missing data; outcome dependent sampling; response selective samples; sequential design; stochastic EM algorithm; Mathematical statistics; Matematisk statistik; Mathematical Statistics; matematisk statistik;

   Sammanfattning : Outcome dependent sampling may increase efficiency in observational studies. It is however not always obvious how to sample efficiently, and how to analyze the resulting data without introducing bias. LÄS MER

3. 12. Modeling Unsteady flow Effects in 3D Throughflow Calculations

   Författare :Magnus Stridh; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; throughflow; turbomachinery; mixing-plane; rotor-stator interaction; cascade; Deterministic stress terms; Linear harmonic; compressor; preconditioned GMRES; Unsteady; linear Navier-Stokes; turbine;

   Sammanfattning : The flow field in a transonic multistage compressor is compressible, three-dimensional and highly unsteady and can be predicted in principle by the exact time-accurate Navier-Stokes equations. The high Reynolds number encountered in multistage turbomachinery together with the wall-bounded nature of the flow environment however prevent the use of DNS to solve the exact N-S equations. LÄS MER

4. 13. Analysis of Some Convolutional Coding Constructions

   Författare :Karin Engdahl; Institutionen för elektro- och informationsteknik; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; turbo-codes; low-density parity-check convolutional codes; low-density codes; PSK; PAM; QAM; coded modulation; multilevel coding; convolutional codes; multilevel modulation; iterative decoding; Informatics; systems theory; Informatik; systemteori;

   Sammanfattning : This thesis focuses on different convolutional coding constructions for digital communication systems, and on methods to analyze these constructions. The work presented in the thesis can be divided into three main areas; error probability bounds for convolutional codes, analysis of multilevel modulation, and investigation of low-density parity-check convolutional codes. LÄS MER

5. 14. Workplace relationships as health-promoting resources at work

   Författare :Sophie Schön Persson; Allmänmedicin och samhällsmedicin; []
   Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Health and well-being; Workplace health promotion; Workplace relationships; Salutogenic;

   Sammanfattning : The purpose of this thesis was to explore workplace relations as resources for health and well-being from a salutogenic perspective. The number of elderly people is increasing in the population and elderly care has already a strained workload, why it is urgent to pay more attention to the salutogenic aspects for employees’ in elderly care. LÄS MER

7. 15. Modeling of Unsteady Flow Effects in Throughflow Calculations

   Författare :Magnus Stridh; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; rotor-stator interaction; mixing-plane; linear Navier-Stokes; cascade; turbomachinery; transport equation; Linear harmonic; compressor; throughflow; turbine; Deterministic stress terms;

   Sammanfattning : In this work an evaluation of a deterministic stress transport model and a linearized Navier-Stokes harmonic approach for including unsteady effects in the steady mixing-plane computations of a multistage transonic compressor has been performed. The results of these two models are compared with those of time-average time-accurate solutions. LÄS MER