You will be provided with a reference and some statements. Please determine whether each statement is 'supported', 'unsupported', or 'unknown' with respect to the reference. Please note:
First, assess whether the reference contains any valid content. If the reference contains no valid information, such as a 'page not found' message, then all statements should be considered 'unknown'.
If the reference is valid, for a given statement: if the facts or data it contains can be found entirely or partially within the reference, it is considered 'supported' (data accepts rounding); if all facts and data in the statement cannot be found in the reference, it is considered 'unsupported'.

You should return the result in a JSON list format, where each item in the list contains the statement's index and the judgment result, for example:
[
    {
        "idx": 1,
        "result": "supported"
    },
    {
        "idx": 2,
        "result": "unsupported"
    }
]

Below are the reference and statements:
<reference>
Client Challenge



A required part of this site couldn’t load. This may be due to a browser
extension, network issues, or browser settings. Please check your
connection, disable any ad blockers, or try using a different browser.
</reference>

<statements>
1. The practical conclusion is that construction is feasible and partially operational, while application claims require stronger independent validation of device validity, privacy, usability, teacher integration and longitudinal learning outcomes
2. The cited architectures aim to convert multimodal data into instructional decisions: edge feedback for immediate movement correction, cloud analysis for long-term personalization, dashboards for teacher intervention and recommendation engines for individualized exercise plans
3. An IoT-based intelligent PE classroom paper describes a five-layer data flow: acquisition, transmission, processing, optimization/analysis and application
4. The IoT conceptual system adds heart-rate variability, oxygen saturation, body temperature, acceleration, velocity, stride frequency, posture angles, ambient conditions and impact forces
5. The IoT paper explicitly states that no physical hardware was built and that it used 1,000 samples from a public dataset
6. The IoT conceptual system includes HRV, SpO2, heart rate, body temperature, kinematics and environmental context
7. The IoT paper describes a dashboard with physiological monitoring, movement/posture analysis, performance feedback classification, participation timelines, skill trends and an alert/recommendation engine
8. The IoT paper frames its work as college and university PE but explicitly states that no physical IoT hardware was built and that it used a public dataset
9. The IoT paper notes noisy and erroneous sensor data and that its pedagogical metrics are computed rather than directly measured
10. The IoT paper states that continuous monitoring involves sensitive physiological and behavioral information that must be protected by institutional regulations and laws
11. The IoT paper lists sensor calibration, implementation cost and network latency as practical adoption constraints
12. The architecture is well specified: terminal sensing, edge inference, cloud personalization, learner modeling, adaptive recommendation, safety monitoring and teacher dashboards
13. A defensible next step is to combine the cloud–edge–end architecture, the digital-base and platform layers, deployed gateway stacks and coaching-generation models under a validation regime that includes device concurrent validity, privacy and security governance
</statements>

Begin the assessment now. Output only the JSON list, without any conversational text or explanations.