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AI-POWERED

Document Insights

and Data Extraction

Full RAG Studio — amended Pfizer capstone

John Raymond TYABA

u2678314@uel.ac.uk

MAIN FINDING

Reliable document AI needs evidence, not just fluent answers.

Multiple PDFs • scanned pages • MiniLM + FAISS • FLAN-T5 • safe fallbacks • citations • abstention

Updated to support a manual 10-question supplier-pack evaluation and one honest failure.

AI-POWERED DOCUMENT INSIGHTS AND DATA EXTRACTION

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Problem Statement | Pharmaceutical Document Intelligence

Extracting verifiable answers from mixed supplier packs, scanned pages and unstructured PDFs

CHALLENGE

Supplier packs combine certificates, specifications, declarations and scans. Manual searching is slow, while a fluent answer is unsafe if the user cannot verify the exact file, page and evidence.

SOLUTION

Users upload one or more PDFs, process them once and ask questions manually. The pipeline applies OCR, metadata-aware chunking, semantic retrieval, grounded generation and safe fallbacks.

PAIN POINT

HOW THE PIPELINE SOLVES IT

Low-text scans

Tesseract OCR fallback

Mixed document types

Classification, filtering and auto-routing

Model or index failure

TF-IDF and extractive fallbacks

Unsupported questions

Similarity threshold and abstention

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System Architecture | Resilient Open-Source RAG Pipeline

Document upload → OCR → chunking → embeddings → FAISS → retrieval → grounded generation / fallback

INPUT

Multiple PDFs

→

OCR

Tesseract 250 DPI

→

CHUNK

900 / 150 overlap

→

EMBED

MiniLM

→

INDEX

FAISS

→

ANSWER

FLAN-T5 / fallback

Component

Technology

Configuration

OCR Engine

Tesseract + PDF2Image

250 DPI; triggered when a page has <40 non-space characters

Text Chunking

Fixed overlapping windows

900 characters; 150-character overlap; page metadata

Embeddings

all-MiniLM-L6-v2

Normalised dense vectors; semantic preferred path

Vector Database

FAISS IndexFlatIP

In-memory inner-product similarity

Retriever

Metadata-filtered dense search

Top-k 1–8; default 4; manual filter + auto-route

LLM

FLAN-T5-small

Deterministic; max_new_tokens = 180

Fallbacks

TF-IDF + extractive answer

Safe retrieval/generation when optional models fail

Prompt Strategy

Context-only grounded prompt

Abstain below configurable similarity threshold

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Pipeline Performance Metrics | Supplier-Certificate Benchmark

10 labelled questions on the supplied AKTA ready Certificate of Quality; one unsupported question included

50%

Answer accuracy

100%

Citation accuracy

27.5%

Average confidence

0%

Abstention rate

END-TO-END QUALITY

5

correct answers

5

incorrect answers

SCOPE AND FAILURE

10

manual questions in exported JSON

34.4%

average top similarity; no question abstained

Actual exported session: dates, process limits and biosafety passed; product name, lot, article, origin and unsupported storage temperature failed.

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Pipeline in Action | Successful Supplier-Certificate Lookup

A grounded numeric answer with source, page, type, score and confidence

QUESTION

“What gamma irradiation range applies to the inlets?”

RETRIEVED EVIDENCE

Certificate of Quality — page 1

“Gamma Irradiation Inlets 25.0–40.0 kGy”

Full RAG Studio

DOCUMENTS

AKTA certificate

Supplier PDF

Scanned page

Process and Index

Questions: 10

What gamma irradiation range applies to the inlets?

25.0–40.0 kGy appears in the returned evidence.

Source: certificate • page 1 • top score 0.551 • confidence 36.8%

PASS

Strength demonstrated: exact process-limit retrieval with visible evidence and citation.

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Pipeline in Action | Honest Unsupported Question

The failure case explains why the amended capstone adds an abstention threshold

QUESTION

“What storage temperature is specified?”

BASELINE FAILURE

The certificate contains no storage temperature.

The exported session still returned unrelated nearest context and did not abstain. This is the clearest production-safety gap.

Full RAG Studio

DOCUMENTS

AKTA certificate

Supplier PDF

Scanned page

Process and Index

Questions: 10

What storage temperature is specified?

Returned autoclave, irradiation and biosafety text instead of abstaining.

Top score 0.324 • confidence 22.9% • abstained = false

FAIL

Required fix: calibrate abstention using labelled queries and add field extraction or post-generation validation for exact identifiers.

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Design Decision Analysis | Reliable on Limited Hardware

Transparency, graceful degradation and maintainability are prioritised

Decision

Rationale

Trade-off

MiniLM embeddings

Fast and lightweight semantic retrieval in Colab

Less pharmaceutical-specific than larger encoders

900 / 150 chunks

Simple, reusable and preserves page evidence

May split tables or clauses across boundaries

FLAN-T5-small

Open-source, deterministic and CPU-friendly

Lower reasoning depth than a larger LLM

FAISS IndexFlatIP

Fast in-memory semantic index

Not persistent or distributed

TF-IDF fallback

Keeps retrieval available if semantic stack fails

Weaker semantic matching for paraphrased questions

Extractive fallback

Keeps answers tied directly to source text

Less fluent than generated answers

Abstention threshold

Prevents unsupported confident answers

Must be calibrated on representative supplier files

KEY TRADE-OFFS

Speed vs. accuracy

Smaller models and in-memory indexing improve demo reliability but reduce domain depth and scale.

Complexity vs. maintainability

Fallbacks and abstention add code paths, but prevent the entire workflow from failing or guessing.

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Current Limitations & Next Steps | Supplier-Pack Roadmap

INPUT QUALITY

Low-DPI, skewed or mixed-layout scans can weaken OCR.

RETRIEVAL

Broad or cross-document questions can spread evidence across chunks.

SCALABILITY

In-memory indexing and synchronous ingestion remain prototype constraints.

PROPOSED ENHANCEMENTS

SHORT TERM

Run ≥10 labelled questions on the real multi-document supplier pack; calibrate abstention and OCR preprocessing.

MEDIUM TERM

Add hybrid BM25 + MiniLM retrieval, cross-encoder reranking and table-aware parsing.

LONG TERM

Persist indexes; add asynchronous ingestion, access control, monitoring and audit logs.

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Project Impact & Learning Outcomes

A working, transparent pipeline designed for technical and non-technical review

TECHNICAL LEARNING

Multiple-file ingestion

OCR and PDF extraction

Dense and sparse retrieval

Grounded prompting

Gradio state and export

POTENTIAL IMPACT

Faster supplier-document lookup

Traceable evidence for review

Safer unsupported-question handling

Reusable architecture across document types

Exportable 10-question sessions

PROFESSIONAL SKILLS

Reliability engineering

Honest metric reporting

Debugging and resilience

Technical documentation

Stakeholder communication

Question for Pfizer: Would a smaller model with grounded extractive fallback be acceptable, or would the team always prefer a larger LLM?

AI-POWERED DOCUMENT INSIGHTS AND DATA EXTRACTION