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 "description": "Append-only Evidence Passport records. Old revisions are immutable; corrections create a new revision and preserve the previous permalink.",
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  "title": "ATSAC Citywide Adaptive Traffic Signals",
  "canonicalUrl": "https://1001smartcities.org/projects/la-atsac/"
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      "ended": null
     }
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      "supportNote": "LADOT says its staff invented the technology; Governing reports the computer systems were developed in-house and maintained internally.",
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      "field": "snippet",
      "text": "first deployed for the 1984 Olympics with 118 signals",
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      "text": "by 2024 connected more than 4,900 signals through 26,000+ sensors and more than 590 cameras",
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      "text": "Los Angeles finished synchronising every signal citywide in February 2013",
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      "text": "In 2022 the control centre moved to a larger site and was expanded ahead of the 2028 Olympics",
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      "text": "LADOT reported average citywide speeds up from 15 to 17.3 mph and intersection delays down 12 percent",
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      "text": "A May 2020 state audit of two state-funded adaptive-control projects found the city had achieved the expected benefits",
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      "id": "src-451adf25987df274",
      "title": "LADOT — ATSAC (authority)",
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      "title": "Patch — Final L.A. Traffic Signals Synchronized (press)",
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       "value": "Ribbon-cutting for the new ATSAC centre ahead of the 2028 Games: the system controlled 118 signals in 1984 and now manages 4,850; renamed Advanced Transportation System and Coordination.",
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       "type": "descriptive-source-note",
       "value": "Reports completion of the network; according to LADOT, Los Angeles is the largest city in the country with complete remote control over every one of its traffic lights.",
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       "type": "descriptive-source-note",
       "value": "Citing LADOT via the Los Angeles Times: average citywide speed up from 15 to 17.3 mph and intersection delays down 12 percent, a 'smoother kind of slow'; a USC engineer notes that faster traffic leads more people to travel.",
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      "title": "LADOT — ATSAC fact sheet (authority)",
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      "locator": {
       "type": "descriptive-source-note",
       "value": "LADOT fact sheet: over 4,900 signalised intersections, over 26,000 vehicle detectors and over 590 CCTV cameras; describes the system as adaptive; its benefits section cites a 2013 Texas A&M study of signal synchronisation in general, not of ATSAC.",
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     "claimsMapped": 12,
     "sourcesTotal": 7,
     "sourcesUsedByClaims": 7,
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     "sourcesWithArchive": 0,
     "sourcesWithExactLocator": 0,
     "sourcesWithContentHash": 0
    },
    "limits": [
     "Publisher names and source languages have not yet been classified; domains are recorded without guessing.",
     "Existing source notes are descriptive locators, not page- or paragraph-exact citations.",
     "A missing archive, publication date or content hash is shown as null rather than inferred.",
     "The project-level evidence grade ranks the strongest source in the entry; it is not a truth score for every claim."
    ]
   }
  }
 ]
}