You should try to insert the following code in your preamble:
\setlength{\headheight}{15pt}
\fancypagestyle{plain}{%
\fancyhf{}
\renewcommand{\headrulewidth}{0pt}
\fancyhead[R]{\thepage}
\fancyhead[C]{\leftmark}}
\pagestyle{plain}
This will print on all your pages the "title" (ToC, LoF, LoT, Chapter name) in the centre of the header and the page number on the upper right of the page. If you want to disable it for one page, use the \thispagestyle{empty} command.
Remark Do not forget to remove this part of your preamble
\fancyhf{}
\renewcommand{\headrulewidth}{0pt}
\rhead{\thepage}
\pagestyle{fancy}
\assignpagestyle{\chapter}{fancy}
\setlength{\headheight}{15pt}
Note You have redefined the labels for the ToC, LoF and LoT which leads to some awkward alignment in the corresponding headers. It is then up to you to decide whether you want to keep them or redefine them.
Edit As suggested by egreg, it is not optimal to redefine the plain style with the \leftmark command. A better way to go is to use the following code in the preamble:
\setlength{\headheight}{15pt}
\pagestyle{fancy}
\fancypagestyle{mystyle}{%
\fancyhf{}
\renewcommand{\headrulewidth}{0pt}
\fancyhead[R]{\thepage}
\fancyhead[C]{\leftmark}}
\pagestyle{mystyle}
and to call \thispagestyle{mystyle} after the ToC, LoF, LoT and each chapter calls if you want to have this style even on these pages. However if the ToC, the LoF or the LoT is longer than one page you will have some problem using this new style because it won't be used on the first page of the concerned table (see this question and answer). In that case one workaround is to redefine the plain style as suggested previously.
A solution can be to redefine \cleardoublepage to be \clearpage locally to those chapters when you don't want that behavior.
So just write
{\let\cleardoublepage\clearpage%
\input{Chapters/Abstract}
\input{Chapters/Abstrakt}
\input{Chapters/Acknowledgements}
\tableofcontents
\listoftables
\listoffigures
}
and you should obtain what you want.
Best Answer
This looks very much like the regular chapter head. Here's the default
report.clsheader(s):I've taken the above, and added font-changing macros (
\chaptertitlefontand\chapternamefont) where needed so you can modify them to suit your needs.Here's a MWE:
\chapternamefontsets the font for Chapter 1 (\scshape\Largeby default) and\chaptertitlefontsets the font for Introduction (\LARGE\bfseriesby default).