Integrated Simulation Platform Research Articles

The Off-Design Performance Simulation of Marine Gas Turbine Based on Optimum Scheduling of Variable Stator Vanes

As one of the antisurge techniques, the adjusting scheme of VSV under off-design conditions has a significant impact on the performance of gas turbines. In this paper, the one-dimensional characteristic of the compressor calculation program is embedded into the zero-dimensional overall gas turbine model, which replaces the original compressor characteristic module. Based on the assembling relationship of the actual components of the marine gas turbine, the architecture of the modular model library is designed, and an integrated simulation platform of marine gas turbine is developed by using MATLAB/GUI software. The influence of the first 3 rows of variable stator vanes of the 9-stage axial compressor working alone on the performance of the compressor at different speeds and different angles was analyzed by the HARIKA compressor characteristic calculation program. Taking the economics and stability of the gas turbine as the optimization objective, the optimization of the first three-stage stator vanes regulation schemes under different working conditions was carried out. The steady-state performance parameters under each working condition of gas turbine of power generation with or without variable stator vane mode were calculated. The study results can provide references for the adjusting scheme of VSV under gas turbine off-design conditions operating process.

Platoon management with cooperative adaptive cruise control enabled by VANET

Previous studies have shown the ability of vehicle platooning to improve highway safety and throughput. With Vehicular Ad-hoc Network (VANET) and Cooperative Adaptive Cruise Control (CACC) system, vehicle platooning with small headway becomes feasible. In this paper, we developed a platoon management protocol for CACC vehicles based on wireless communication through VANET. This protocol includes three basic platooning maneuvers and a set of micro-commands to accomplish these maneuvers. Various platooning operations such as vehicle entry and vehicle (including platoon leader) leaving can be captured by these basic platoon maneuvers. The protocol operation is described in detail using various Finite State Machines (FSM), and can be applied in collaborative driving and intelligent highway systems. This protocol is implemented in an integrated simulation platform, VENTOS, which is developed based on SUMO and OMNET++. The validity and effectiveness of our approach is shown by means of simulations, and different platooning setting are calibrated.

IEEE 802.11p for cellular offloading in vehicular sensor networks

The use of vehicles as sensors is a new paradigm to enable an efficient environment monitoring and an improved traffic management. In most cases, the sensed information must be collected at a remote control center and one of the most challenging aspects is the uplink acquisition of data from vehicles, which is presently performed through cellular networks. With the objective to offload cellular networks, in this paper we propose and discuss the adoption of the WAVE/IEEE 802.11p protocols, which represent the state of the art for short range vehicle-to-vehicle and vehicle-to-roadside communications. More specifically, we discuss the system design and assess the cellular resource saving that can be obtained in urban scenarios through the deployment of WAVE/IEEE 802.11p devices on the vehicles and roadside units, evaluating the impact of the percentage of equipped vehicles, of the number of deployed road side units, and of the adopted routing protocol. Results, obtained through an integrated simulation platform taking both realistic vehicular environments and wireless network communication aspects into account, show that the deployment of few road side units and the use of low complexity routing protocols leads to a significant reduction of cellular resource occupation, even approaching 100% with a high density of equipped vehicles.

Integrated Simulation Platform for Crisis Management — the Concept of its Construction and Use in the Field of Training

Integrated Simulation Platform for Crisis Management — the Concept of its Construction and Use in the Field of Training

Preoperative simulation for the planning of microsurgical clipping of intracranial aneurysms.

The safety and success of intracranial aneurysm (IA) surgery could be improved through the dedicated application of simulation covering the procedure from the 3-dimensional (3D) description of the surgical scene to the visual representation of the clip application. We aimed in this study to validate the technical feasibility and clinical relevance of such a protocol. All patients preoperatively underwent 3D magnetic resonance imaging and 3D computed tomography angiography to build 3D reconstructions of the brain, cerebral arteries, and surrounding cranial bone. These 3D models were segmented and merged using Osirix, a DICOM image processing application. This provided the surgical scene that was subsequently imported into Blender, a modeling platform for 3D animation. Digitized clips and appliers could then be manipulated in the virtual operative environment, allowing the visual simulation of clipping. This simulation protocol was assessed in a series of 10 IAs by 2 neurosurgeons. The protocol was feasible in all patients. The visual similarity between the surgical scene and the operative view was excellent in 100% of the cases, and the identification of the vascular structures was accurate in 90% of the cases. The neurosurgeons found the simulation helpful for planning the surgical approach (ie, the bone flap, cisternal opening, and arterial tree exposure) in 100% of the cases. The correct number of final clip(s) needed was predicted from the simulation in 90% of the cases. The preoperatively expected characteristics of the optimal clip(s) (ie, their number, shape, size, and orientation) were validated during surgery in 80% of the cases. This study confirmed that visual simulation of IA clipping based on the processing of high-resolution 3D imaging can be effective. This is a new and important step toward the development of a more sophisticated integrated simulation platform dedicated to cerebrovascular surgery.

Using an integrated simulation environment for the risk based design of advanced driver assistance systems

When designing new Advanced Driver Assistance Systems (ADAS), the existing guidelines like the RESPONSE 3 Code of Practice imply intense testing of the system prior series production. Within the EU-FP7-Project ISi-PADAS a new methodology of risk based design has been established which includes an integrated simulation platform. This integration enables intense testing of new prototypes in an accelerated way and therefore enhances the design process while directly combining the simulation results with a risk matrix.This paper describes the new methodology while focussing on the software framework and the procedure of risk assessment in detail. It shows the general approach as well as the appropriate steps taken for an ADAS prototype developed in the context of ISi-PADAS.

Integrated simulation of the dualistic water cycle and its associated processes in the Haihe River Basin

Water resource shortages, water environmental deterioration, and water ecological degradation are becoming increasingly prominent in the Haihe River Basin under the effects of global climate change and intense human activity. Finding ways to solve these problems reasonably is an urgent task in basin water resources management. The water cycle describes the formation and transformation of every water drop, while it interacts with associated water ecology and water environment processes. Therefore, to fundamentally solve the above problems, the three processes must be combined and the evolutionary trends of the ecology and water environment driven by the water cycle must be determined. To comprehensively diagnose and solve the problems of water resources, ecology and water environment in the basin, an integrated simulation platform of the dualistic water cycle and its associated processes in the Haihe River Basin was established by fully analyzing the “natural-social” dualistic characteristics of the evolution of the basin water cycle in this study. Accordingly, it is a supporting tool to evaluate the future trends of water resources, ecology and the water environment by setting scenarios based on the predictions of a climate mode and water control conditions. The results show that with climate change, the water consumption, groundwater overexploitation, and the amount of water flowing to the sea could develop soundly and satisfy the requirements of national economic growth in the future planning year 2030 through the implementation of water consumption control management and the South-North Water Diversion Project. Meanwhile, associated water environmental deterioration can be alleviated, and a growing trend for production capacities of the natural ecosystem and agro-ecosystem is seen. The above results provide a foundation for implementing basin water resources regulation and the most strict water resources management.

Integrated Simulation Platform Based on Multi-Source Data

The operating departments of power system use different information systems for work convenience. The differences in appliances, data sources, structures and maintenance personnel lead to the independence between data sources as well as heavy workload of data exchange and maintenance. The simulation of different problems needs various tools while the establishment of grid model requires hard work. This paper, on the basis of function requirement analysis, made project design of integrative simulation platform, and developed a data graphical integrated modeling platform featuring the functions of steady state, electromechanical transient and electromagnetic transient with the ability of multi-source data fusion by using the programming language C#. The platform can integrate data of PSDB, PSD-BPA and PMIS, automatically form PSASP and PSD-BPA power flow calculation data, electromechanical transient simulation data and generate “.psc” files for PSCAD\EMTDC electromagnetic transient simulation analysis according to the selected sectors and components on the graphical interfaces.

Integrated Traffic and Communication Performance Evaluation of an Intelligent Vehicle Infrastructure Integration (VII) System for Online Travel-Time Prediction

This paper presents a framework for online highway travel-time prediction using traffic measurements that are likely to be available from vehicle infrastructure integration (VII) systems, in which vehicle and infrastructure devices communicate to improve mobility and safety. In the proposed intelligent VII system, two artificial intelligence (AI) paradigms, i.e., artificial neural networks (ANNs) and support vector regression (SVR), are used to determine future travel time based on such information as the current travel time and VII-enabled vehicles' flow and density. The development and performance evaluation of the VII-ANN and VII-SVR frameworks, in both the traffic and communications domains, were conducted using an integrated simulation platform for a highway network in Greenville, SC. In particular, the simulation platform allows for implementing traffic surveillance and management methods in the traffic simulator PARAMICS and for evaluating different communication protocols and network parameters in the communication network simulator, Network Simulator version 2 (ns-2). This paper's findings reveal that the designed communications system can support the travel-time prediction functionality. The findings also demonstrate that the travel-time prediction accuracy of the VII-AI framework was superior to a baseline instantaneous travel-time prediction algorithm, with the VII-SVR model slightly outperforming the VII-ANN model. Moreover, the VII-AI framework was shown to perform reasonably well during nonrecurrent congestion scenarios, which have traditionally challenged sensor-based highway travel-time prediction methods.

Development of a Finite Element Data Exchange System for chain simulation of manufacturing processes

A Finite Element Data Exchange System (FEDES) is developed to transfer and map finite element analysis (FEA) data between different FE solvers and meshes. Six commercial FE codes (ABAQUS, ANSYS, DEFORM, MSC.MARC, MORFEO and VULCAN) are incorporated in FEDES. Four mapping techniques are developed and embedded in FEDES which allow the data mapping between meshes with different element types and densities. The algorithms of the mapping techniques are described and compared for 2D and 3D models. The design and capabilities of FEDES are also described. Results from the data transfer and mapping between different FE simulations are presented and discussed. Two manufacturing chains are simulated using FEDES in this paper. The first manufacturing chain is simulated on a parallelepiped geometry including casting, forging and heat treatment processes. The second manufacturing chain is simulated on an aero-engine vane component including metal deposition, welding, heat treatment, machining and shot-peening processes. The development of FEDES demonstrates an integrated simulation platform for modelling manufacturing chains of processes using different FE solvers and meshes.

Optimal Co-Design of Control Algorithm and Bandwidth Scheduling for Networked Control Systems

The performance of Networked Control System (NCS) is not only determined by controller, but also by network QoS. In this paper, aiming at the bandwidth scheduling problem of multiple closed loop control system, an approximate linear function of continuous system performance with delay and sample period is proposed firstly, and then the optimal scheduling algorithm under both non-preemptive rate monotonic (NPRM) schedulability constraint and NCS stability constraint is proposed which is to optimize the overall performance of NCS. Moreover, an algorithm of sample periods harmonization is presented to improve the bandwidth utilization. A reservation-based schedule of non-period data is also taken into account. Finally, an integrated simulation platform based on Truetime is present, and the experimental results show that the scheme is more effective than the former ones.

Deterministic and stochastic channel models implemented in a physical layer simulator for Car-to-X communications

Abstract. This paper presents a physical (PHY) layer simulator of the IEEE 802.11p standard for Wireless Access in Vehicular Environments (WAVE). This simulator allows the emulation of data transmission via different radio channels as well as the analysis of the resulting system behavior. The PHY layer simulator is part of an integrated simulation platform including a traffic model to generate realistic mobility of vehicles and a 3D ray-optical model to calculate the multipath propagation channel between transmitter and receiver. Besides deterministic channel modeling by means of ray-optical modeling, the simulator can also be used with stochastic channel models of typical vehicular scenarios. With the aid of this PHY layer simulator and the integrated channel models, the resulting performance of the system in terms of bit and packet error rates of different receiver designs can be analyzed in order to achieve a robust data transmission.

Integrated Synthesis of Control and Bandwidth Scheduling on Networked Control Systems

Many Networked Control Systems (NCS) comprise several control loops that are closed over a network of computation nodes. In those systems, periodic, sporadic and non-periodic packets share the network bandwidth, complex timing behavior and communication lead to delay and jitter, which both degrade the control performance. That is to say the performance of NCS is determined not only by control algorithms, but also by the quality of serves (QoS) of network. Therefore, the network QoS must be considered during the controller synthesis. Also, the control performance should be taken into account during system scheduling. In this paper, a control–scheduling co-design method that integrates controller and scheduler design is proposed. The transmission periods of control packets are calculated to optimize the overall performance of control loops. The transmission phases and resource utilization of sporadic and non-periodic packets are controlled by the resource reservation server running on each node to guarantee the temporal requirements of those data and also to limit the effect on the transmission of control packets. Further more, a harmonization algorithm of transmission periods of packets is also presented to improve the bandwidth utilization. An integrated simulation platform based on Truetime is present, and the experimental results show that the scheme is more effective than the former ones.

Research on Kinematics of High Speed Linear Feed System

The feed unit is modeled with Solidworks entity, then the combined mechatronic simulation is studied with MATLAB and ADAMS, In this paper，control of information exchange was completed by defining the system input and output variables, it build a mechatronic integrated simulation platform of high speed linear feed system of type GD-3. The acceleration, velocity and displacement curve of linear feed system are simulated and compared with experimental results on optimization of parameters. The results indicate that the mechatronic integrated simulation of virtual prototyping can better analyze and evaluate the velocity and displacement Kinematics characteristics of high-speed linear feed system, the acceleration different between the simulation and experimental is 10.71 percent and the virtual prototyping simulation is verified to be a new approach for analysis of the kinematics characteristics of the high-speed linear feed system.

NCTUns tool for wireless vehicular communication network researches

Several goals such as improving road safety and increasing transport efficiency are being pursued in intelligent transportation systems (ITS). Wireless vehicular communication is one technology to achieve these goals. Conducting vehicular experiments on the roads is an approach to studying the effectiveness of wireless vehicular communication. However, such an approach is costly, hard-to-control (repeat), dangerous, and infeasible when many vehicles and people are involved in the field trial. In contrast, the simulation approach does not have these problems. It is a very useful approach and complements the field trial approach. This paper presents NCTUns, an open source integrated simulation platform, for wireless vehicular communication network researches. This tool tightly integrates network and traffic simulations and provides a fast feedback loop between them. Therefore, a simulated vehicle can quickly change its driving behavior such as moving speed and direction when it receives a message from the wireless vehicular communication network. This capability is required by several novel ITS applications such as active collision avoidance systems. In this paper, we present the design, implementation, validation, and performance of this tool.

A Web-based Remote Simulation System for the Glass Pressing Process

Numerical simulation of the glass pressing process has become popular and software application by Application Service Provider (ASP) instead of customers' local installation has expanded rapidly. An approach to create a remote ASP-oriented simulation tool for the glass pressing process is presented in this paper. The original functionality of the simulation system is divided into several independent modules: main server, job scheduler, simulating units and user interface (including visualization). The construction approach and implementation techniques of the system are described in detail. Furthermore, the united model and methodology is presented to establish an integrated simulation platform for the multiple aspects of the forming process. The modeling and formulation of glass pressing, part cooling, mold cooling residual stresses and shrinkage are also discussed.

How Equalization Techniques Affect the TCP Performance of MC-CDMA Systems in Correlated Fading Channels

This paper investigates the impact of several equalization techniques for multicarrier code division multiple access systems on the performance at both lower and upper layers (i.e., physical and TCP layers). Classical techniques such as maximal ratio combining, equal gain combining, orthogonality restoring combining, minimum mean square error, as well as a partial equalization (PE) are investigated in time- and frequency-correlated fading channels with various numbers of interferers. Their impact on the performance at upper level is then studied. The results are obtained through an integrated simulation platform carefully reproducing all main aspects affecting the quality of service perceived by the final user, allowing an investigation of the real gain produced by signal processing techniques at TCP level.

705 生命化された統合数値計算プラットフォームを用いた、大規模流体構造連成問題のプレポスト処理(OS-7A 大規模連成解析と関連話題,OS-7 大規模連成解析と関連話題)

705 生命化された統合数値計算プラットフォームを用いた、大規模流体構造連成問題のプレポスト処理(OS-7A 大規模連成解析と関連話題,OS-7 大規模連成解析と関連話題)

生命化された統合数値計算プラットフォームにおけるユビキタスなユーザーインターフェイスについて(OS22e CGと計算力学)

生命化された統合数値計算プラットフォームにおけるユビキタスなユーザーインターフェイスについて(OS22e CGと計算力学)