In order to do requirement-based testing of embedded system, we must have correct requirement specifications. But, natural language requirements of a client have ambiguity, inaccuracy, and inconsistency. To solve these problems, natural language requirements are modeled with modeling language such as UML and Simulink. During a modeling phase, the requirements are rearranged and retranslated in use-case. These activities are disadvantages of modeling. In this paper, we propose the technique, which is how to model a embedded system requirement into a model without rearranging and retranslating. This technique 1) represent a embedded system requirement with graphical language, and 2) model a requirement into a model. Because this technique only describes "what-to-do" of the requirement, this technique is useful to not only the low-level requirements but also the high-level requirements. We show some example systems modeled by REED, which has adopted this technique.

Customers' requirements written in a natural language are rewritten to modeling language in development phases. In many cases, those who participate in development cannot understand requirements written in modeling language. This paper proposes the translation technique from the requirement model which is written by REED(REquirement EDitor) tool into a natural language in order to help for the customer understanding requirement model. This technique consists of three phases: 1 st phase is generating the IORT(Input-Output Relation Tree), 2 nd phase is generating the RTT(Requirement Translation Tree), 3 rd phase is translating into a natural language.

Many different types of snap-fits have been developed to replace conventional fasteners, and research efforts have been made to characterize their performance. It is often tedious to look for design equations for unique types of snap-fits to calculate the insertion and retention forces. If found, these equations tend to be long, complex, and difficult to use. For this reason, a snap-fit calculator has been created to help in designing integral attachment features. Studies of seven most commonly used snap-fits (annular snap, bayonet-and-finger, cantilever hook, cantilever-hole, compressive hook, L-shaped hook, and U-shaped, hook) were used to provide the equations implemented in this snap-fit calculator, more fasteners than any other snap-fit calculator available. This tool aids in designing snap-fits to meet specific loading requirements by allowing the designer to size the feature to obtain desired estimates for maximum insertion and retention forces. The software for this design tool was written in JAVA™ language that is independent of operating system platforms and can be distributed at a company site-wide over an intranet or worldwide over the Internet. This makes it easily accessible to a user, and universal upgrades can be achieved by simply updating the software at the server location. Designers will find this tool to be useful in the design process and the most convenient way to estimate the performance of snap-fits. This paper describes the development and operation of the IFP snap-fit calculator including several case studies comparing the calculated results to experimental data.

A relation between generated test cases and an original requirement is important, but it becomes very complex because a relation between requirement models and requirements are m-to-n in automatic test case generation based on models. In this paper, I suggest automatic generation technique for REED (REquirement EDitor), 1-to-1 requirement modeling tool. Test cases are generated though 3 steps, Coverage Target Generation, IORT (Input Output Relation Tree)Generation, and Test Cases Generation. All these steps are running automatically. The generated test cases can be generated from a single requirement. As a result of applying to three real commercial systems, there are 5566 test cases for the Temperature Controller, 3757 test cases for Bus Card Terminal, and 4611 test cases for Excavator Controller.