To simulate the satellite launch mission under a general platform which could be used in a full-digital mode as well as in a semi-physical way, is an important way to certify the mission design performance as well as ...To simulate the satellite launch mission under a general platform which could be used in a full-digital mode as well as in a semi-physical way, is an important way to certify the mission design performance as well as technical feasibilities, and it relates to complex system simulation methods such as multi-disciplinary coupling, multi-language modeling as well as interactive simulation and virtual simulation technologies. This paper introduces the design of a digital simulation platform for satellite launch mission verification.The platform has the advantages of high generality and extensibility, being easy to build up. The Functional Mockup Interface(FMI) Standard is adopted to achieve integration of multi-source models. A WebGL based 3D visual simulation tool is also adopted to implement the virtual display system which could display the rocket launch process and rocket-satellite separation with high fidelity 3D virtual scenes. A configuration tool was developed to map the 3D objects in the visual scene with simulation physical variables for complex rocket flight control mechanisms, which greatly improves the platform's generality and extensibility. Finally the real-time performance had been tested and the YL-1 launch mission was adopted to demonstrate the functions of the platform.The platform will be used to construct a digital twin system for satellite launch missions in the future.展开更多
This paper describes the results of a project on the inspection of visually inaccessible areas of nuclear containment liners and shells via the advanced Magnetostrictive sensor (MsS) Guided Wave (GW) nondestructive in...This paper describes the results of a project on the inspection of visually inaccessible areas of nuclear containment liners and shells via the advanced Magnetostrictive sensor (MsS) Guided Wave (GW) nondestructive inspection technique. Full scale mockups that simulated shell and liner regions of interest in the containment of both a Pressurized Water Reactor (PWR) and Boiling Water Reactor (BWR) were constructed. Inspections were performed on the mock-ups in three stages to discern the signal attenuation caused by flaws and caused by concrete in the structures. The effect of concrete being in close proximity to the liner and shell was determined, and the capability to detect and size flaws via this GW technique was evaluated.展开更多
In this work, we present DUSM （Disciplined Use Cases with Screen Mockups）, a novel method for describing and refining requirements specifications based on disciplined use cases and screen mockups. Disciplined use ca...In this work, we present DUSM （Disciplined Use Cases with Screen Mockups）, a novel method for describing and refining requirements specifications based on disciplined use cases and screen mockups. Disciplined use cases are characterized by a quite stringent template to prevent common mistakes, and to increase the quality of the specifications. Use cases descriptions are formulated in a structured natural language, which allows to reach a good level of precision, avoiding the need for further notations and complex models. Screen mockups are precisely associated with the steps of the use cases scenarios and they present the corresponding GUIs （graphical user interfaces） as seen by the human actors before/after the steps executions, improving the comprehension and the expression of the non-functional requirements on the user interface. DUSM has been proposed and fine-tuned during several editions of a software engineering course at the University of Genova. Then, by means of a series of case studies and experiments, we validated the method and evaluated： 1） its effectiveness in improving the comprehension and, in general, the quality of the produced requirements specification, and 2） its applicability in the industry, where the method has been found useful and not particularly onerous.展开更多
文摘To simulate the satellite launch mission under a general platform which could be used in a full-digital mode as well as in a semi-physical way, is an important way to certify the mission design performance as well as technical feasibilities, and it relates to complex system simulation methods such as multi-disciplinary coupling, multi-language modeling as well as interactive simulation and virtual simulation technologies. This paper introduces the design of a digital simulation platform for satellite launch mission verification.The platform has the advantages of high generality and extensibility, being easy to build up. The Functional Mockup Interface(FMI) Standard is adopted to achieve integration of multi-source models. A WebGL based 3D visual simulation tool is also adopted to implement the virtual display system which could display the rocket launch process and rocket-satellite separation with high fidelity 3D virtual scenes. A configuration tool was developed to map the 3D objects in the visual scene with simulation physical variables for complex rocket flight control mechanisms, which greatly improves the platform's generality and extensibility. Finally the real-time performance had been tested and the YL-1 launch mission was adopted to demonstrate the functions of the platform.The platform will be used to construct a digital twin system for satellite launch missions in the future.
文摘This paper describes the results of a project on the inspection of visually inaccessible areas of nuclear containment liners and shells via the advanced Magnetostrictive sensor (MsS) Guided Wave (GW) nondestructive inspection technique. Full scale mockups that simulated shell and liner regions of interest in the containment of both a Pressurized Water Reactor (PWR) and Boiling Water Reactor (BWR) were constructed. Inspections were performed on the mock-ups in three stages to discern the signal attenuation caused by flaws and caused by concrete in the structures. The effect of concrete being in close proximity to the liner and shell was determined, and the capability to detect and size flaws via this GW technique was evaluated.
文摘In this work, we present DUSM （Disciplined Use Cases with Screen Mockups）, a novel method for describing and refining requirements specifications based on disciplined use cases and screen mockups. Disciplined use cases are characterized by a quite stringent template to prevent common mistakes, and to increase the quality of the specifications. Use cases descriptions are formulated in a structured natural language, which allows to reach a good level of precision, avoiding the need for further notations and complex models. Screen mockups are precisely associated with the steps of the use cases scenarios and they present the corresponding GUIs （graphical user interfaces） as seen by the human actors before/after the steps executions, improving the comprehension and the expression of the non-functional requirements on the user interface. DUSM has been proposed and fine-tuned during several editions of a software engineering course at the University of Genova. Then, by means of a series of case studies and experiments, we validated the method and evaluated： 1） its effectiveness in improving the comprehension and, in general, the quality of the produced requirements specification, and 2） its applicability in the industry, where the method has been found useful and not particularly onerous.
