本論文提出了一系列轉換操作，用於在高階方塊圖上編輯和重構系統架構，同時維護所設計系統的相關特徵關係，完善了嵌入式系統工具的設計空間探索機制。在主流的嵌入式系統設計方法中，為了讓設計師可以直觀且方便地設計系統，通常會使用方塊圖來表示系統的高階架構，並提供基本的編輯功能。然而，元件通常具有固定的封裝邊界，且在如今 SoC 的發展趨勢下，基本的結構編輯功能已不足以滿足設計師的需求。因此，大多設計師仍會選擇手動編輯電路圖來設計系統，但這樣的做法容易出錯，原因是設計意圖無法明確表示，導致電路圖難以維護。此外，傳統的系統設計工具很少將提供的設計空間探索機制與系統或元件資訊關聯起來，通常僅支援結構性編輯。這導致設計師需要在腦中追蹤系統的所有資訊及對應關係，容易造成設計過程的不斷迭代，不僅缺乏嚴謹性也容易出錯。

我們應用了基於特徵的模型作為方塊圖和電路圖背後的中間表示，其捕捉了與功能、結構、參數和概念相關的資訊，作為設計中系統的完整模型，而方塊圖和電路圖則分別作為該模型在高階與低階層次上的結構投影。我們提供的轉換方法可以在方塊圖編輯器、電路圖編輯器或演算法中被調用，以在編輯或細化實作的過程中保持特徵關係的一致性。相比於直接編輯特徵模型可能需要顧慮過多細節，面對高階的方塊圖進行設計對使用者而言更為直觀。我們透過一個實際的嵌入式系統設計範例來評估我們的轉換方法。結果顯示，在整個設計過程中，我們的轉換方法不僅支援設計師通過重構方塊圖來探索不同的封裝程度與資源配置方案，還能有效維持特徵模型中代表系統核心功能的特徵流。

This thesis proposes a series of transformation operations for editing and restructuring the system architecture at the high-level block diagram while maintaining the associated feature relations for the system under design, thereby optimizing the design space exploration mechanism of our system design tool. In mainstream embedded system design methodologies, block diagrams are commonly used to represent the high-level architecture of a system, offering designers an intuitive way to design systems with basic editing functions. However, as components generally have fixed packaging boundaries, and with the trends in SoC development, these basic structural editing functions are no longer sufficient for designers. As a result, many designers still opt to design systems by manually editing schematics, a process prone to errors due to the difficulty of maintaining and verifying complex details. Additionally, traditional system design tools rarely integrate design space exploration mechanisms with system or component information, typically supporting only structural editing. This requires users to mentally track all information and relationships of system under design, leading to error-prone and iterative design processes that lack rigor.

We adapt a feature-based model as an intermediate representation (IR) behind the block diagram and circuit diagram, which captures the information related to functions, structure, parameters, and concepts as a comprehensive model of the system under design. The block diagram and the schematic serve as structural projections of this model at high and low levels, respectively. Our API can be invoked by a block-diagram editor, schematic editor, or an algorithm during editing or refinement towards implementation while maintaining the feature relations consistently. Editing in the structural view is more intuitive to the user compared to editing the feature model directly, which can be overwhelming or error-prone.

We evaluate our transformation methods using a practical example of embedded system design. Results show that our transformation methods not only facilitate user restructuring on the block diagram when exploring different ways for COTS components to cover the required features and different resource allocation schemes such as bus bandwidth and power distribution, but also effectively maintain the feature flow representing the core functionality expected by the user.

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