缺少字体形状

Question

我遇到了缺少字体形状的问题。我正在处理讲义并对一个非常大的乳胶文档进行了一些更正，所以我没有自己设置所有内容。现在我遇到了一个问题，即章节和小节中的某些数学符号被替换为黑色方块。该文档使用 hvmath.sty 和 tools.sty。头文件如下所示（文档中只有一个部分）：

\documentclass[a4paper,12pt,pointlessnumbers,twoside,final]{scrbook}
%\documentclass[a4paper,12pt,pointlessnumbers,oneside,draft]{scrbook}
%\documentclass[a4paper,12pt,pointlessnumbers,twoside,draft]{scrbook}

%Draft als Hintergrund
%\usepackage[light,first,timestamp]{draftcopy}

\usepackage[outline,none,landscape,bottom]{draftcopy}
\draftcopyName{\today}{100}

\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}
\usepackage{lmodern}
\usepackage[intlimits]{amsmath}
\usepackage{amsxtra}
\usepackage{amssymb}
\usepackage{mathrsfs}
%labels werden angezeigt
\usepackage{showkeys}
\usepackage{graphicx}
\usepackage{dsfont}
\usepackage{multirow}
%\usepackage{bbding}
% fuer alte grafiken
\usepackage{epsfig}
% Boldface-math environment in all headings
\usepackage{hvmath}
\usepackage{pstricks-add}
\usepackage{pst-all}

\usepackage{subfigure}
%\usepackage[varumlaut]{yfonts}

\usepackage{tools}
\usepackage{psfrag}
\usepackage{pstricks-add}

\usepackage{scalefnt}
\usepackage{tikz}
\tikzset{>=stealth}
\tikzset{
  big arrow/.style={
    decoration={markings,mark=at position 1 with {\arrow[scale=3,#1]{>}}},
    postaction={decorate},
    shorten >=0.4pt},
  big arrow/.default=black}
\tikzset{
  big arrow2/.style={
    decoration={markings,mark=at position 1 with {\arrow[scale=2,#1]{>}}},
    postaction={decorate},
    shorten >=0.4pt},
  big arrow2/.default=black}
\usetikzlibrary{intersections, decorations,circuits.ee.IEC, calc, decorations.markings, patterns}
\usepackage{pgfplots}
\pgfplotsset{compat=newest}

% zur indexerstellung
\usepackage{index}
\makeindex

%%%%%%%%%%%%%% pssignpost definition %%%%%%%%%%%%%%%%%%%%%%%%%%%%%

\makeatletter
\def\pssignpost[#1]#2#3{
\psframebox[framearc=0.5,framesep=.4,fillstyle=solid,fillcolor=lightgray]{\parbox{2.5cm}{\sf\bfseries\begin{tabular}{p{1.25cm}*{2}rr} #2 & #3\end{tabular}}}
\psline[#1](-1.8,-.64)(-1.8,.9)
\pstriangle[linecolor=black,fillstyle=solid,fillcolor=lightgray,gangle=90](-.4,.13)(1.9,-1.75)
\psframe[linecolor=lightgray,fillstyle=solid,fillcolor=lightgray](-.5,-.585)(-.25,.858)
}
\makeatother

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

%Weniger Worttrennungen
\sloppy

\graphicspath{{Bilder/}}

\addtokomafont{captionlabel}{\sffamily\bfseries\small}
\addtokomafont{caption}{\small}
%kein Einzug/Absatz bei Bildunterschriften
\setcapindent{0em}
%Für verbesserten Seitenumbruch
\tolerance=270 \emergencystretch=30pt

% Boldface-math environment in al headings
\addtokomafont{sectioning}{\mathversion{hvmathbold}}

%%%%%%%%%%%%%% part definition %%%%%%%%%%%%%%%%%%%%%%%%%%%%%

\renewcommand*{\partformat}{\thepart~}
\renewcommand*{\partpagestyle}{empty}


\makeatletter
\def\@part[#1]#2{%
    \ifnum \c@secnumdepth >-2\relax
      \refstepcounter{part}%
      \@maybeautodot\thepart%
      \addcontentsline{toc}{part}{\protect\numberline{\thepart}#1}%
    \else
      \addcontentsline{toc}{part}{#1}%
    \fi
    \partmark{#1}%
    {%\@parskipfalse\@parskip@indent %auskommentiert, da fehlermeldung unter windows!
    \centering
     \interlinepenalty \@M
     \normalfont\sectfont
     \ifnum \c@secnumdepth >-2\relax
       \size@partnumber\partformat
       %\par
       %\vskip 20\p@
     \fi
    \size@part #2\strut\par}%
    \@endpart}
\makeatother
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

\begin{document}
\section{Relativistically invariant $\Delta$-functions}
\end{document}

当我编译它时，部分中的 \Delta 被替换为黑色方块，并收到以下警告

LaTeX Font Warning: Font shape `OMX/phv/b/n' undefined
(Font)              using `OMX/cmex/m/n' instead on input line 121.

有人知道怎么解决这个问题吗？我