diff --git a/fhir-date-offene-periods.svg b/fhir-date-offene-periods.svg
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+++ b/fhir-date-offene-periods.svg
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+<svg xmlns="http://www.w3.org/2000/svg" width="1100" height="830" viewBox="0 0 1100 830" font-family="Segoe UI, Arial, sans-serif">
+<rect width="1100" height="830" fill="#ffffff"/>
+<text x="550.0" y="30" font-size="22" font-weight="700" fill="#1a1a2e" text-anchor="middle">FHIR date: Matching gegen offene (unvollstaendige) Period/Range</text>
+<text x="550.0" y="52" font-size="14" fill="#555" text-anchor="middle">Fehlender Start = -unendlich  |  Fehlendes Ende = +unendlich  |  Pfeilspitze = offenes Ende</text>
+<text x="550.0" y="72" font-size="12.5" fill="#777" text-anchor="middle">Suchwert: date=&lt;praefix&gt;2023-06-15</text>
+<text x="30" y="110" font-size="20" font-weight="700" fill="#111">gt</text>
+<text x="30" y="130" font-size="12.5" fill="#555">Fehlendes Ende = +unendlich -&gt; ueberlappt fast immer den oberen Bereich.</text>
+<rect x="680.0" y="138" width="360.0" height="16" fill="#1565c0" opacity="0.12"/>
+<line x1="240" y1="146" x2="1040" y2="146" stroke="#333" stroke-width="1.5"/>
+<polygon points="1040,146 1033,142 1033,150" fill="#333"/>
+<line x1="680.0" y1="126" x2="680.0" y2="166" stroke="#c62828" stroke-width="2.5" />
+<text x="680.0" y="120" font-size="11.5" fill="#c62828" text-anchor="middle" font-weight="600">Suchgrenze (2023-06-15)</text>
+<rect x="640.0" y="167" width="380.0" height="18" rx="4" fill="#546e7a" opacity="0.75"/>
+<polygon points="1020,176 1006,167 1006,185" fill="#546e7a"/>
+<text x="830.0" y="208" font-size="11" fill="#444" text-anchor="middle">Period D: nur Start (laeuft noch)</text>
+<path d="M 821.0 154 l 6 6 l 12 -13" stroke="#2e7d32" stroke-width="3.5" fill="none" stroke-linecap="round" stroke-linejoin="round"/>
+<rect x="260" y="167" width="410.0" height="18" rx="4" fill="#546e7a" opacity="0.75"/>
+<polygon points="260,176 274,167 274,185" fill="#546e7a"/>
+<text x="465.0" y="208" font-size="11" fill="#444" text-anchor="middle">Period E: nur Ende (Start unbekannt)</text>
+<line x1="456.0" y1="145" x2="474.0" y2="163" stroke="#c62828" stroke-width="3.5" stroke-linecap="round"/><line x1="456.0" y1="163" x2="474.0" y2="145" stroke="#c62828" stroke-width="3.5" stroke-linecap="round"/>
+<rect x="260" y="167" width="760" height="18" rx="4" fill="#546e7a" opacity="0.75"/>
+<polygon points="260,176 274,167 274,185" fill="#546e7a"/>
+<polygon points="1020,176 1006,167 1006,185" fill="#546e7a"/>
+<text x="640.0" y="208" font-size="11" fill="#444" text-anchor="middle">Period F: weder Start noch Ende bekannt</text>
+<path d="M 631.0 154 l 6 6 l 12 -13" stroke="#2e7d32" stroke-width="3.5" fill="none" stroke-linecap="round" stroke-linejoin="round"/>
+<text x="30" y="280" font-size="20" font-weight="700" fill="#111">sa</text>
+<text x="30" y="300" font-size="12.5" fill="#555">Fehlender Start = -unendlich -&gt; kann NIE vollstaendig 'danach' liegen.</text>
+<rect x="680.0" y="308" width="360.0" height="16" fill="#1565c0" opacity="0.12"/>
+<line x1="240" y1="316" x2="1040" y2="316" stroke="#333" stroke-width="1.5"/>
+<polygon points="1040,316 1033,312 1033,320" fill="#333"/>
+<line x1="680.0" y1="296" x2="680.0" y2="336" stroke="#c62828" stroke-width="2.5" stroke-dasharray="4,4"/>
+<text x="680.0" y="290" font-size="11.5" fill="#c62828" text-anchor="middle" font-weight="600">Suchgrenze (2023-06-15)</text>
+<rect x="640.0" y="337" width="380.0" height="18" rx="4" fill="#546e7a" opacity="0.75"/>
+<polygon points="1020,346 1006,337 1006,355" fill="#546e7a"/>
+<text x="830.0" y="378" font-size="11" fill="#444" text-anchor="middle">Period D: nur Start (laeuft noch)</text>
+<line x1="821.0" y1="315" x2="839.0" y2="333" stroke="#c62828" stroke-width="3.5" stroke-linecap="round"/><line x1="821.0" y1="333" x2="839.0" y2="315" stroke="#c62828" stroke-width="3.5" stroke-linecap="round"/>
+<rect x="260" y="337" width="410.0" height="18" rx="4" fill="#546e7a" opacity="0.75"/>
+<polygon points="260,346 274,337 274,355" fill="#546e7a"/>
+<text x="465.0" y="378" font-size="11" fill="#444" text-anchor="middle">Period E: nur Ende (Start unbekannt)</text>
+<line x1="456.0" y1="315" x2="474.0" y2="333" stroke="#c62828" stroke-width="3.5" stroke-linecap="round"/><line x1="456.0" y1="333" x2="474.0" y2="315" stroke="#c62828" stroke-width="3.5" stroke-linecap="round"/>
+<rect x="260" y="337" width="760" height="18" rx="4" fill="#546e7a" opacity="0.75"/>
+<polygon points="260,346 274,337 274,355" fill="#546e7a"/>
+<polygon points="1020,346 1006,337 1006,355" fill="#546e7a"/>
+<text x="640.0" y="378" font-size="11" fill="#444" text-anchor="middle">Period F: weder Start noch Ende bekannt</text>
+<line x1="631.0" y1="315" x2="649.0" y2="333" stroke="#c62828" stroke-width="3.5" stroke-linecap="round"/><line x1="631.0" y1="333" x2="649.0" y2="315" stroke="#c62828" stroke-width="3.5" stroke-linecap="round"/>
+<line x1="30" y1="415" x2="1040" y2="415" stroke="#ddd" stroke-width="1"/>
+<text x="30" y="450" font-size="20" font-weight="700" fill="#111">lt</text>
+<text x="30" y="470" font-size="12.5" fill="#555">Fehlender Start = -unendlich -&gt; ueberlappt fast immer den unteren Bereich.</text>
+<rect x="240" y="478" width="440.0" height="16" fill="#1565c0" opacity="0.12"/>
+<line x1="240" y1="486" x2="1040" y2="486" stroke="#333" stroke-width="1.5"/>
+<polygon points="1040,486 1033,482 1033,490" fill="#333"/>
+<line x1="680.0" y1="466" x2="680.0" y2="506" stroke="#c62828" stroke-width="2.5" />
+<text x="680.0" y="460" font-size="11.5" fill="#c62828" text-anchor="middle" font-weight="600">Suchgrenze (2023-06-15)</text>
+<rect x="640.0" y="507" width="380.0" height="18" rx="4" fill="#546e7a" opacity="0.75"/>
+<polygon points="1020,516 1006,507 1006,525" fill="#546e7a"/>
+<text x="830.0" y="548" font-size="11" fill="#444" text-anchor="middle">Period D: nur Start (laeuft noch)</text>
+<path d="M 821.0 494 l 6 6 l 12 -13" stroke="#2e7d32" stroke-width="3.5" fill="none" stroke-linecap="round" stroke-linejoin="round"/>
+<rect x="260" y="507" width="410.0" height="18" rx="4" fill="#546e7a" opacity="0.75"/>
+<polygon points="260,516 274,507 274,525" fill="#546e7a"/>
+<text x="465.0" y="548" font-size="11" fill="#444" text-anchor="middle">Period E: nur Ende (Start unbekannt)</text>
+<path d="M 456.0 494 l 6 6 l 12 -13" stroke="#2e7d32" stroke-width="3.5" fill="none" stroke-linecap="round" stroke-linejoin="round"/>
+<rect x="260" y="507" width="760" height="18" rx="4" fill="#546e7a" opacity="0.75"/>
+<polygon points="260,516 274,507 274,525" fill="#546e7a"/>
+<polygon points="1020,516 1006,507 1006,525" fill="#546e7a"/>
+<text x="640.0" y="548" font-size="11" fill="#444" text-anchor="middle">Period F: weder Start noch Ende bekannt</text>
+<path d="M 631.0 494 l 6 6 l 12 -13" stroke="#2e7d32" stroke-width="3.5" fill="none" stroke-linecap="round" stroke-linejoin="round"/>
+<text x="30" y="620" font-size="20" font-weight="700" fill="#111">eb</text>
+<text x="30" y="640" font-size="12.5" fill="#555">Fehlendes Ende = +unendlich -&gt; kann NIE vollstaendig 'davor' liegen.</text>
+<rect x="240" y="648" width="440.0" height="16" fill="#1565c0" opacity="0.12"/>
+<line x1="240" y1="656" x2="1040" y2="656" stroke="#333" stroke-width="1.5"/>
+<polygon points="1040,656 1033,652 1033,660" fill="#333"/>
+<line x1="680.0" y1="636" x2="680.0" y2="676" stroke="#c62828" stroke-width="2.5" stroke-dasharray="4,4"/>
+<text x="680.0" y="630" font-size="11.5" fill="#c62828" text-anchor="middle" font-weight="600">Suchgrenze (2023-06-15)</text>
+<rect x="640.0" y="677" width="380.0" height="18" rx="4" fill="#546e7a" opacity="0.75"/>
+<polygon points="1020,686 1006,677 1006,695" fill="#546e7a"/>
+<text x="830.0" y="718" font-size="11" fill="#444" text-anchor="middle">Period D: nur Start (laeuft noch)</text>
+<line x1="821.0" y1="655" x2="839.0" y2="673" stroke="#c62828" stroke-width="3.5" stroke-linecap="round"/><line x1="821.0" y1="673" x2="839.0" y2="655" stroke="#c62828" stroke-width="3.5" stroke-linecap="round"/>
+<rect x="260" y="677" width="410.0" height="18" rx="4" fill="#546e7a" opacity="0.75"/>
+<polygon points="260,686 274,677 274,695" fill="#546e7a"/>
+<text x="465.0" y="718" font-size="11" fill="#444" text-anchor="middle">Period E: nur Ende (Start unbekannt)</text>
+<path d="M 456.0 664 l 6 6 l 12 -13" stroke="#2e7d32" stroke-width="3.5" fill="none" stroke-linecap="round" stroke-linejoin="round"/>
+<rect x="260" y="677" width="760" height="18" rx="4" fill="#546e7a" opacity="0.75"/>
+<polygon points="260,686 274,677 274,695" fill="#546e7a"/>
+<polygon points="1020,686 1006,677 1006,695" fill="#546e7a"/>
+<text x="640.0" y="718" font-size="11" fill="#444" text-anchor="middle">Period F: weder Start noch Ende bekannt</text>
+<line x1="631.0" y1="655" x2="649.0" y2="673" stroke="#c62828" stroke-width="3.5" stroke-linecap="round"/><line x1="631.0" y1="673" x2="649.0" y2="655" stroke="#c62828" stroke-width="3.5" stroke-linecap="round"/>
+</svg>
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