Domain: Engineering — Nuclear Engineering
Target concept: Nuclear Reactor Instrumentation

Video generation prompt: The reactor neutron flux measurement experimental setup (including a BF3 neutron detector, flux meter host, and a simulated core neutron source) involves gradually moving the detector from the edge to the center of the core. The simulated neutron source is then activated, and the display of the host unit is focused on.

Evaluation guide:
(i) Target concept: Spatial dependence of neutron flux in a reactor core, measured via gas-filled proportional counter. Minimum mechanism: Detector must be physically positioned within the flux gradient field; activation must introduce a measurable neutron field; readout must reflect position-dependent signal amplitude.
(ii)Storyline: Frame 1–3: Static wide shot showing BF3 detector at core edge, flux meter host, and inactive simulated source. Frame 4–7: Continuous detector motion toward core center along fixed radial axis, maintaining cable connection and orientation. Frame 8: Distinct activation action (e.g., button press or LED transition) on source unit. Frame 9–10: Stable close-up on flux meter display showing elevated numeric value; no occlusion, no cut, fixed viewpoint; display must be legible and updated post-activation.

Manual:
Experimental Procedure
1. Position BF3 neutron detector at edge of simulated core.
2. Move detector steadily inward along radial line toward core center.
3. Activate simulated neutron source.
4. Observe flux meter host display.
Observation of Experimental Phenomena
- BF3 detector is cylindrical, metallic, connected via coaxial cable to flux meter host.
- While the detector moves from the edge toward the center, the flux meter host display stays at its baseline (zero or minimal) reading, since the simulated neutron source has not yet been activated.
- Upon source activation, display value rises sharply and stabilizes at an elevated level.
Summary of Experimental Principles
Neutron flux intensity is highest at core center; BF3 detectors ionize proportionally to local thermal neutron flux; flux meter converts pulse rate to real-time analog/digital readout.

Prompt Grounding rubric:
level_1: None of the three objects (BF3 detector, flux meter host with display, simulated core source) are recognizable; the detector never moves from its starting position; no activation action (switch, button, or light change) occurs on the source; no display screen is shown at any point.
level_2: At least one of the three objects appears, but they are not arranged as a working setup (e.g., the detector is not connected by cable to the host, or the source sits apart from the core region); the detector stays stationary throughout; the host's display is absent or blank for the entire clip.
level_3: All three objects are present and visually distinct: a cylindrical metallic detector with a coaxial cable running to the flux meter host, and a separate box-shaped source unit with an ON/OFF indicator; the detector is shown moving along a path from the edge toward the center of the core region; the source's activation action is depicted (e.g., a button press or the indicator light changing); the host's display is visible and shows a numeric readout.
level_4: All of score 3, AND the detector's inward movement is one continuous, unbroken motion from edge to center rather than a series of jumps; the activation action happens only after the detector has reached its final near-center position, not before or during the move; the display stays centered in frame and fully visible, without being blocked or cut away, for the entire observation portion of the clip.
level_5: All of score 4, AND the detector ends up seated within the core region itself, not merely resting beside it; the activation is unmistakable, e.g., a red indicator light switches on at the same moment the display begins to change; the coaxial cable stays connected and visibly taut from detector to host throughout the move; the display's digits stay sharp and readable at every point they are shown.

Scientific and Causal Correctness rubric:
level_1: The display's reading has no connection to the detector's position or to the activation event: for example it stays at zero throughout, or shows values that change randomly regardless of where the detector sits or whether the source has been switched on.
level_2: The display's value changes before the source is activated (implying a flux reading with the source still off), or the display shows no response right after activation, or its value stays the same no matter where the detector sits once the source is on.
level_3: The display holds at its baseline (zero or minimal) reading throughout the detector's move from edge to center, since the source has not yet been switched on; only after the activation action does the display's value rise; the reading taken with the detector near the center after activation is visibly higher than the baseline reading taken at the edge.
level_4: All of score 3, AND the display's jump to an elevated value happens right at the moment of activation, not gradually beforehand and not delayed well afterward; the elevated reading is noticeably larger than the baseline value, consistent with the detector now sitting in a higher-flux region; the detector's position at the moment of activation (near the core center) matches where the elevated reading is taken.
level_5: All of score 4, AND the causal chain is unambiguous from watching the clip alone: baseline reading while inactive and near the edge, detector moves inward with the reading still flat, activation occurs with the detector now at the center, and the reading rises sharply and holds steady at the new elevated level; the display shows no flicker, freeze, or error characters anywhere in this sequence.

Spatiotemporal Consistency rubric:
level_1: The detector jumps to a new spot between frames instead of sliding smoothly; the flux meter host or the source unit vanishes and reappears partway through the clip; the room lighting suddenly flips (e.g., bright to dark in a single frame) with no other change; the detector's size or angle changes abruptly with no corresponding motion.
level_2: The detector's inward motion contains visible jumps or freezes (holding the exact same pose for several frames, then skipping ahead); the host's display blanks out for an instant; the source's indicator light changes state with a visible skip rather than a smooth transition; the coaxial cable appears to detach or snap momentarily during the move.
level_3: The detector slides along one continuous straight path from edge to center; the detector, host, and source all stay in their places in the frame the whole time, with no unexplained gap change between them; the lighting stays even, with no unexplained shadow jump or flicker; nothing about the detector, cable, or housings looks warped, transparent, or torn between frames.
level_4: All of score 3, AND the detector's travel speed looks even and unbroken, without stutter; the cable trails naturally behind the moving detector rather than staying rigid or floating free of it; the host's display refreshes cleanly with no tearing or blockiness; the overall brightness and color tone stay the same from one frame to the next.
level_5: All of score 4, AND the camera's framing never pans, tilts, or zooms; it holds one fixed view for the whole clip; the detector stays the same size and stays in focus throughout its move; nothing about the detector's motion blur looks faster or slower than its actual travel speed; the source's indicator light, once switched on, holds steady rather than strobing or pulsing oddly.