本論文採用資料分佈式服務(Data Distribution Service, DDS)傳輸協定，取代現有飲水機系統之超文本傳輸協定(Hyper Text Transfer Protocol, HTTP)，以解決HTTP 之資料傳輸延遲過高所造成資料 取樣筆數不足的問題。採用 DDS 雖可降低傳輸延遲並可提高資料取樣筆數，但需解決 DDS 不支援非關聯式資料庫、傳輸時會佔用過多記憶體導致裝置停機，以及提高資料取樣筆數後造成資料庫過載等議題。針對上述議題，本論文自行開發可執行於 DDS 訂閱方的非關聯式資料庫驅動程式以及可根據記憶體用量自動重啟裝置的程式，並提出可依資料變動頻率來選擇的 DDS 發佈/訂閱傳輸機制。相較於採用 HTTP 傳輸協定的系統，平均資料傳輸延遲從 659.4 毫秒降到 8.6 毫秒，取樣時間由 30 秒降至 1 秒但實際傳輸的資料量僅增為 12.1 倍

Abstract —This paper uses the Data Distribution Service (DDS) transfer protocol to replace the Hyper Text Transfer Protocol (HTTP) of the existing water dispenser system to solve the problem of insufficient data sampling caused by the high data transmission delay of HTTP. Although the use of DDS can reduce the transmission delay and increase the number of data samplings, it needs to solve the problems that DDS does not support non-associated databases, it will occupy too much memory during transmission and cause the device to be shut down, and increasing the number of data samplings will cause database overload. In order to correct the above mentioned issues, this paper proposes and develops a non-associative database driver that can be executed by DDS subscribers, a program that can automatically restart the device according to memory usage, and proposes DDS publish/subscribe transmission that can be selected according to the frequency of data changes mechanism.
Compared with the system using the HTTP transmission protocol, the average data
transmission delay is reduced from 659.4 milliseconds to 8.6 milliseconds, and the sampling period is reduced from 30 seconds to 1 second, but the actual amount of data transferred only increases to 12.1 times.

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