Fabrication and Performance of a 40-MHz Linear Array Based on a 1-3 Composite with Geometric Elevation Focusing
Bibliographic record
Abstract
The fabrication and performance of a 256-element high-frequency (40-MHz) linear array is described. The array was fabricated using a high-frequency 1-3 PZT-polymer composite material developed in our laboratory. The spacing of the pillars in the composite was chosen to match the 40-microm center-to-center element spacing of the array electrodes. The element electrodes were created using photolithography, and connections to the electrodes were made using ultrasonic wire bonding. The array was focused in the elevation direction by geometrically shaping the composite material using a cylindrical die with a 6-mm radius of curvature. The resulting transducer produced pulses with a -6 dB two-way bandwidth of 50% and a peak-to-peak pressure of 503 kPa when excited with a +/-30 V monocycle pulse. The measured one-way (-6 dB) directivity for a single array element was 24 degrees and the -3 dB one-way elevation beamwidth was measured to be 130 microm. The radiation pattern for a focused 64-element subaperture was measured by mechanically translating the aperture above a needle hydrophone. A -3 dB one-way beamwidth of 97 microm was found at a depth of 6 mm. The one-way radiation pattern decreased smoothly to less than -30 dB at a lateral distance of 640 microm.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
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 | 0.000 | 0.001 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.002 | 0.001 |
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".