Optimization of primary beam for x-ray dual-mode imager comprising radiography and coherent scatter
Bibliographic record
Abstract
Medical, industrial, and security x-ray systems should give images that demonstrate material contrast for accurate identification. Novel devices use both coherently-scattered x rays and primary to acquire images. In our system, the same detector is used for primary and scatter. The primary information being detected post object must be attenuated so that both the primary and scatter are within the detector’s dynamic range. Initially, we used 1.5-mm-thick post-object attenuator disks of 90% tungsten/10% copper alloy. In this work, we investigate whether reducing the incident beam’s x-ray tube potential and using less attenuating materials can increase primary image quality. Our final attenuating material is 1.0 mm cerium. This scales all three of primary signal-to-noise-ratio, signal size, and signal-difference-to-noise-ratio by approximately a factor of 10. The scatter values remained relatively unchanged. Additional filtration placed upstream at the collimator could bear further investigation.
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How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.001 | 0.001 |
| Meta-epidemiology (narrow) | 0.001 | 0.001 |
| Meta-epidemiology (broad) | 0.001 | 0.001 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.002 | 0.001 |
| Open science | 0.001 | 0.000 |
| Research integrity | 0.001 | 0.001 |
| Insufficient payload (model declined to judge) | 0.005 | 0.002 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".