Plant Landscape Design Language of Small Street Parks in Tropical Coastal Regions:A Case Study of Zhanjiang City

Small urban street parks play an irreplaceable role in protecting ecological environment of cities and beautifying living spaces of citizens, in these parks plant is an essential landscaping element that can not only improve environmental quality, but also provide visual enjoyment for viewers. There are many small street parks in Zhanjiang City, however, plant landscapes in such parks lack in regional characteristics because of blind copy and random planting. By analyzing plant landscapes in typical street parks in Zhanjiang, and borrowing the theoretical research framework of linguistics, this paper concluded the vocabulary, sentence,chapter and grammatical rules of plant landscape design, in order to explore new methods for the plant landscape design of small parks in tropical coastal regions.

IoT-Enabled Autonomous System Collaboration for Disaster-Area Management

Timely investigating post-disaster situations to locate survivors and secure hazardous sources is critical,but also very challenging and risky.Despite first responders putting their lives at risk in saving others,human-physical limits cause delays in response time,resulting in fatality and property damage.In this paper,we proposed and implemented a framework intended for creating collaboration between heterogeneous unmanned vehicles and first responders to make search and rescue operations safer and faster.The framework consists of unmanned aerial vehicles(UAVs),unmanned ground vehicles(UGVs),a cloud-based remote control station(RCS).A light-weight message queuing telemetry transport(MQTT)based communication is adopted for facilitating collaboration between autonomous systems.To effectively work under unfavorable disaster conditions,antenna tracker is developed as a tool to extend network coverage to distant areas,and mobile charging points for the UAVs are also implemented.The proposed framework’s performance is evaluated in terms of end-to-end delay and analyzed using architectural analysis and design language(AADL).Experimental measurements and simulation results show that the adopted communication protocol performs more efficiently than other conventional communication protocols,and the implemented UAV control mechanisms are functioning properly.Several scenarios are implemented to validate the overall effectiveness of the proposed framework and demonstrate possible use cases.

AADL2TASM: a Verification and Analysis Tool for AADL Models

Architecture analysis and design language (AADL) is an architecture description language standard for embedded real-time systems and it is widely used in safety-critical applications. For facilitating verification and analysis, model transformation is one of the methods. A synchronous subset of AADL and a general methodology for translating the AADL subset into timed abstract state machine (TASM) were studied . Based on the atlas transformation language (ATL) framework, the associated translating tool AADL2TASM was implemented by defining the meta-model of both AADL and TASM, and the ATL transformation rules. A case study with property verification of the AADL model was also presented for validating the tool.

Validation of static properties in unified modeling language models for cyber physical systems

Cyber physical systems (CPSs) can be found nowadays in various fields of activity. The increased interest for these systems as evidenced by the large number of applications led to complex research regarding the most suitable methods for design and development. A promising solution for specification, visualization, and documentation of CPSs uses the Object Management Group (OMG) unified modeling language (UML). UML models allow an intuitive approach for embedded systems design, helping end-users to specify the requirements. However, the UML models are represented in an informal language. Therefore, it is difficult to verify the correctness and completeness of a system design. The object constraint language (OCL) was defined to add constraints to UML, but it is deficient in strict notations of mathematics and logic that permits rigorous analysis and reasoning about the specifications. In this paper, we investigated how CPS applications modeled using UML deployment diagrams could be formally expressed and verified. We used Z language constructs and prototype verification system (PVS) as formal verification tools. Considering some relevant case studies presented in the literature, we investigated the opportunity of using this approach for validation of static properties in CPS UML models.

Architecture-level particular risk modeling and analysis for a cyber-physical system with AADL

Cyber-physical systems(CPSs)are becoming increasingly important in safety-critical systems.Particular risk analysis(PRA)is an essential step in the safety assessment process to guarantee the quality of a system in the early phase of system development.Human factors like the physical environment are the most important part of particular risk assessment.Therefore,it is necessary to analyze the safety of the system considering human factor and physical factor.In this paper,we propose a new particular risk model(PRM)to improve the modeling ability of the Architecture Analysis and Design Language(AADL).An architecture-based PRA method is presented to support safety assessment for the AADL model of a cyber-physical system.To simulate the PRM with the proposed PRA method,model transformation from PRM to a deterministic and stochastic Petri net model is implemented.Finally,a case study on the power grid system of CPS is modeled and analyzed using the proposed method.