目前有許多的研究提出不同的方式，以建構智慧環境的服務組合。大多數的研究中，朝著主動感知使用者的需求，動態組合使用者所需要的服務資源，提供更具有智慧的環境。在這些服務組合系統中，期望不需要使用者的介入，就能自動的產生出所需的服務。我們認為使用者的需求是複雜且多變的，因此使用者應該適當的介入服務組合的過程，來提升服務組合系統的可用性與接受度。甚至，藉由使用者的創作，服務組合會更具有創造力。
本論文提出一個新的服務組合模型，它能快速、簡易、有效率且符合使用者需求。從使用者的角度，可利用現有的服務，組合出新的服務；從系統的角度而言，具備自發性活化服務元件之特性，該特性依據服務元件是否需要被使用，主動的活化或是釋放服務資源，以增進服務平台的資源可利用性。該模型具有四項特色：(1) 藉由視窗介面，讓使用者可以依照自己的需求，制定服務組合的關係；(2) 與其他相關研究相較之下，服務設計者或是使用者不需要面對複雜的架構，就能實現服務組合；(3) 服務元件之間的綁定是動態的；(4) 當情境服務執行完成後，該情境服務所佔用的系統資源，是允許釋放的。
此外，服務組合模型也實作於OSGi服務平台中。數種情境可透過一個圖形化工具來驗證服務組合系統的雛型。再者，透過模擬的方式，進一步評估本研究所提出的活化服務元件機制，來印證可行性與效率。

There have been many studies dedicated to constructing smart homes by using service composition techniques. Most of them aim at providing intelligent service composition systems by exploiting either users’ preferences or techniques based on learning users’ habits. Technically, these service composition systems are built without any user intervention in order for greater automaticity. However, user requirements are varied and somewhat subjective in natural. In this regard, we advocate user’s intervention to increase the feasibility of the service composition system, in which more creative services can be built by users using existing services offering functionalities and/or data.
This study proposes a novel model for quickly building a simple, efficient and user-friendly service composition system in a smart space (e.g. smart home). From the user’s view, it can utilize/compose the existing services to form a new service or services. From the system perspective, a spontaneous service activation technique (i.e. on-demand activate and deactivate services) is developed to improve the resource utilization of the service platform. The main characteristics of the proposed model include: (1) a user-friendly GUI interface for a user to compose the existing services; (2) no complex data model and learning model are required, thus simpler in both design and use, in comparison with existing studies; (3) the binding of services is dynamic; and (4) when a scenario is run to completion, the occupied resources required by the involved services can be released automatically, thus enhancing the efficiency of resource utilization.
We implement and evaluate the service composition system on an OSGi service platform. A prototype of the service composition model, along with a GUI-based tool, is presented to demonstrate the feasibility based on a number of common scenarios. Furthermore, a simulator is developed to evaluate the proposed service activation method; the results demonstrate its practicability and efficiency.

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