The concept of Level of Service (LoS) is not inherently supported by Systems Modeling Language (SysML), the standard modeling notation for model‐based systems engineering. This paper describes and demonstrates an approach that enhances SysML to enable LoS modeling and evaluation. A SysML profile enables the definition and visual verification of LoS during system operation, via LoS specific requirements, inside the system model, and the association of these requirements with specific system components. Hence, static and dynamic aspects of the system model are used for the LoS verification, while specific design alternatives are automatically proposed, in case the desired LoS is not achieved. As a proof of concept, the proposed approach was applied to explore passenger comfort, a key LoS metric, indicating space available to passenger in Railway Transportation Systems (RTSs). A specific case study on passenger comfort for the Athens Metro was conducted to derive insights regarding the practical aspects of the proposed approach.

中文翻译：

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使用SysML建模和探索服务水平：铁路运输系统中的乘客舒适度案例

服务级别（LoS）的概念不受系统建模语言（SysML）的固有支持，SysML是基于模型的系统工程的标准建模符号。本文描述并演示了一种增强SysML以实现LoS建模和评估的方法。SysML概要文件可通过系统模型内部的LoS特定需求，以及这些需求与特定系统组件的关联，在系统运行期间对LoS进行定义和可视化验证。因此，系统模型的静态和动态方面都用于LoS验证，而在未实现所需LoS的情况下，会自动提出特定的设计替代方案。作为一种概念验证，所提出的方法被用于探索乘客的舒适度，这是一项关键的LoS指标，指示铁路运输系统（RTS）中可供乘客使用的空间。进行了有关雅典地铁乘客舒适度的具体案例研究，以得出有关拟议方法实际方面的见解。