An Algorithm for Large-Scale Terrain Generation Based on Quadtree

2013 ◽  
Vol 446-447 ◽  
pp. 946-950
Author(s):  
Nai Mei Fan ◽  
Zhi Feng Zhang

The paper puts forward an algorithm for multi-resolution terrain model generation based on quadtree. This algorithm puts elements as view-dependent and terrain relief into the evaluation standards for level of detail and raises appropriate methods to remove cracks in the course of terrain generation according to the law of node partition and rendering. In drawing terrain, optimized display technologies as frustum culling, backface culling, triangle fan and static data storage. Test results show, this algorithm can realize the real-time visualization of large-scale terrain.

2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
Zhi Li

With the wide application of science and technology in the field of weapons, shock wave is an important breakthrough point in weapon research, and the storage and testing system of shock wave is a breakthrough point that people pay most attention to at present. Shock wave data storage has the characteristics of large scale, complex structure, low cost efficiency, and strong timeliness. This paper mainly studies the design of shock wave storage test system with variable parameters based on numerical piezoelectric circuit sensor. Based on fluid dynamics simulation theory and numerical simulation method, the normal and concave-convex three-dimensional models of two pressure measuring devices are constructed by using the flow waveform of calculator, and then, the network is divided. The results show that, under the same inlet pressure, the larger the bulge or depression value, the greater the influence on the experimental results. The influence of disk is 10% higher than that of pen, and the change rate of relative difference is increased by 1.5% with the increase of concave-convex value. Finally, experiments are carried out in different environments to verify the reliability, survivability, and flexibility. The shock wave storage test system is optimized when the parameters of the digital voltage circuit sensor are variable.


2007 ◽  
Vol 70 (12) ◽  
pp. 2732-2740 ◽  
Author(s):  
JOHN R. RUBY ◽  
JUN ZHU ◽  
STEVEN C. INGHAM

To develop a process for predicting the likelihood of Salmonella contamination on beef carcasses, we evaluated the influence of several possible causative factors (i.e., year, abattoir, day of week, month, and intervention system components) on the risk of Salmonella and indicator organism contamination. Hide and carcass sponge samples were collected in 2005 to 2006 in six steps at three abattoirs in the East (A), Midwest (B), and Southwest (C) United States. Each abattoir used the same intervention system. Samples were analyzed for aerobic plate counts (APCs; n = 18,990) and Enterobacteriaceae counts (EBCs; n = 18,989) and the presence or absence of Salmonella (n = 5,355). Our results demonstrated that many factors play a significant role in the level of microbial contamination of beef carcasses. Overall, Salmonella prevalence and EBC levels were significantly higher in 2006 than in 2005. APCs and EBCs were highest in abattoirs A (3.57 log CFU/100 cm2) and B (1.31 log CFU/100 cm2). The odds of detecting a positive Salmonella isolate were greatest in abattoir C and lowest in abattoir A. Across the three abattoirs, the overall intervention process effectively reduced microbiological contamination. Salmonella prevalence fell from 45% (preevisceration) to 0.47% (postchilled–lactic acid), and there were APC and EBC reductions of 5.43 and 5.28 log CFU/100 cm2, respectively, from hide-on to postchilled–lactic acid samples. At each abattoir, composites of three individual EBC-negative carcass samples yielded Salmonella-negative results 97 to 99% of the time. These results suggest the possibility of using indicator test results to accurately predict the absence of Salmonella in a beef carcass sample.


2010 ◽  
Vol 36 ◽  
pp. 293-296
Author(s):  
Yoshio Kurosawa ◽  
Takao Yamaguchi

We have developed a technique for estimating vibrations of an automotive body structures with viscoelastic damping materials using large-scale finite element (FE) model, which will enable us to grasp and to reduce high-frequency road noise(200~500Hz). In the new technique, first order solutions for modal loss factors are derived applying asymptotic method. This method saves calculation time to estimate modal damping as a practical tool in the design stages of the body structures. Frequency responses were calculated using this technique and the results almost agreed with the test results. This technique can show the effect of the viscoelastic damping materials on the automotive body panels, and it enables the more efficient layout of the viscoelastic damping materials. Further, we clarified damping properties of the automotive body structures under coupled vibration between frames and panels with the viscoelastic damping materials.


Author(s):  
Andy P. Broeren ◽  
Mark G. Potapczuk ◽  
Sam Lee ◽  
Adam M. Malone ◽  
Bernard P. Paul ◽  
...  

2013 ◽  
Vol 765-767 ◽  
pp. 1087-1091
Author(s):  
Hong Lin ◽  
Shou Gang Chen ◽  
Bao Hui Wang

Recently, with the development of Internet and the coming of new application modes, data storage has some new characters and new requirements. In this paper, a Distributed Computing Framework Mass Small File storage System (For short:Dnet FS) based on Windows Communication Foundation in .Net platform is presented, which is lightweight, good-expansibility, running in cheap hardware platform, supporting Large-scale concurrent access, and having certain fault-tolerance. The framework of this system is analyzed and the performance of this system is tested and compared. All of these prove this system meet requirements.


2011 ◽  
Vol 82 ◽  
pp. 722-727 ◽  
Author(s):  
Kristian Schellenberg ◽  
Norimitsu Kishi ◽  
Hisashi Kon-No

A system of multiple degrees of freedom composed out of three masses and three springs has been presented in 2008 for analyzing rockfall impacts on protective structures covered by a cushion layer. The model has then been used for a blind prediction of a large-scale test carried out in Sapporo, Japan, in November 2009. The test results showed substantial deviations from the blind predictions, which led to a deeper evaluation of the model input parameters showing a significant influence of the modeling properties for the cushion layer on the overall results. The cushion properties include also assumptions for the loading geometry and the definition of the parameters can be challenging. This paper introduces the test setup and the selected parameters in the proposed model for the blind prediction. After comparison with the test results, adjustments in the input parameters in order to match the test results have been evaluated. Conclusions for the application of the model as well as for further model improvements are drawn.


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