Research On Urban Environmental Three Dimensional Noise Analysis Model And Visul Assessment Based On VRGIS

Noise pollution has always been a global concern which is a major factor in dissatisfaction with the environment. With the implement of automatic monitoring system of environmental noise, how to ascertain monitoring stations to really reflect the urban noise environment quality? Whether can build a 3DGIS-based noise analysis model to improve accuracy and combine the sound ray with 3DGIS spatial analysis perfectly? How to determine proper acoustics for high-rise buildings? How to visualize the invisible noise and build a 3D interactive virtual reality noise environment with new methods and technology? The above questions are real challenges faced by researchers and state authorities.Bearing the idea of watch and calculation integration in mind, this paper adopts technical route VR-GIS, various methods and technologies are imployed, such as environmental noise monitoring theory, GIS, spatial analysis, acoustic theory. The paper focuses on five key thematic issues relevant to the urban environmental noise.1) PSO based dynamic clustering algorithm IEPSO-KM to optimize noise monitoring stationsThe optimization of noise monitoring stations is Non-deterministic Polynomial complete problem. It is well known that K-means algorithm is one of the most widely used clustering techniques. However, solutions of K-means algorithm depend on the initialization of cluster centers and the final solution converges to local minima. The proposed algorithm IEPSO-KM is elaborately developed by combining Particle Swarm Optimization (PSO) and K-means algorithms that helps find better cluster partition. The efficiency of the proposed algorithm is evaluated by QingDao Shinan district data sets. The simulation results show that the proposed algorithm outperforms K-means.2) 3D analysis model of urban environmental noiseNoise models play an important role in any planning and decision making process. Systematic approach of generating noise models is essential to arrive at effective solution. The proposed comprehensive model is based on geometrical ray theory and theory of diffraction and calculations are carried out in one-third octave bands. In the model ground surface properties is characterized by its impedance and roughness.The model is applicable for any non-flat terrain approximated by a segmented terrain shape, including flat, valley-shape and hill-shaped terrain. The model may also include the effect of reflection from obstacles.3) Urban noise analysis model of high rise buildingsTraditional models are built with the noise levels of on particular height. In the reality, noise travels in all direction. Residents living in high rise buildings are also severely affected by noise. It is therefore important to develop noise analysis model of high rise buildings. In this paper, traffic noise parameters measurement engages noise and spectrum analysis device, the study focus on vertical characterstics of noise to assess residential suitability. Emphasis is placed on the construction of noise analysis model of high rise building employing BP neural network algorithm.4) Visualization of urban environmental noiseIn order to organize and manage environmental noise spatial data effectively and represent 3D spatial entity integrally, simulation modeling algorithm with TIN, CSG and B-Rep is developed to construct 3D interactive virtual reality environment. The efficient and effective method has developed to generate 3D observation points, which represent location of virtual microphones where noise levels are to be calculated. The interactive visualization is carried by contour based on Delaunay triangulation and octree-based 3D texture volume rendering. This paper is base on the actual development of VRGIS Platform by the Marine Information Technology laboratory of Ocean University of China, provides a 3D interactive virtual realitiy environment for the viewer to walk and fly through the 3D space to grasp the noise information, at the same time, adopt FFD technology to relazie noise virtual perception.5) Implement and application of noise visualized assessment system based on VRGISThe development and validation of a comprehensive VRGIS based noise visualized assessment system is presented, the system integrated VR and GIS seamlessly. This paper describes system flow and noise assessement sequence diagrams. The system has been validated to some extent based on results of measurements and by comparison with result of calculation using accurate numerical models. Attempt to extend the utilization of research achievement for combination of urban traffic planning and noise strategic plan. The main innovations of this thesis are summarized as follows.1) Science innovation. This research work developed a new methodology to resolve urban noise pollution with spatial analysis and geostaticstical methods of GIS, virtual reality thchnology and ntelligence technology.â‘ Combining Particl Swarm Optimization (PSO), dynamic clustering algorithm is developed and verified through optimized result of noise monitoring stations of QingDao shinan district.â‘¡This research work developed a methodology to build 3D noise models to analyse the three dimensional effect of noise pollution within a GIS. The spatial analysis and geostaticstical methods of GIS can play an important role to control noise pollution. GIS provide framework to integrate noise calculation models with spatial data that can be used for building noise maps.â‘¢Analysis model of high rise buildings can show influence of noise in all direction, it is essential to urban environmental assessment for dimensional city.2) Technological innovation. Innovative using noise vision technology and virtual reality to urban environmental noise assessment, this research work provides a 3D interactive virtual reality environment, for the viewer to walk and fly through the 3D space to grasp the noise information. The immersion virtual reality can serve the public and professionals by providing a user-friendly 3D tool for understanding noise impacts of various planning options and effectiveness of mitigation measures at the initial stage of planning. The public can navigate the virtual space, recognize their familiar vicinity and appreciate the future noise environment of different project options and different forms of mitigation measures instantly.3) Application innovation.â‘ With the conversion from plan pattern traditional city to dimensional future city, Environmental noise assessment is implemented around high rise buildings via 3DGIS, open up new application for 3DGIS;â‘¡With constraint of urban environmental noise capacity, a bilevel optimal model can calculate the maximum carrying capacity of road networks in urban and provide a reference for planning and decision making.