Model Construction and Visualization Simulation of Soybean Root System

This paper mainly focused on the growth law, model construction and visualization of a soybean root. A pot experiment was conducted in the laboratory to collect root system data and measure soybean root＇s length, diameter and number by excavating in different periods. On the basis of an in-depth analysis of root structure geometry, we analyzed the collected experimental data with logistic equations, and got the growth of soybean root equation, according to its morphological structure characteristics of self-similarity, and discussed the virtual modeling method on the soybean root based on L-system and in Visual c＋＋ Using OpenGL technology to achieve a soybean root system topology model and visualization simulation.

VISUAL SIMULATION OF COLD ROLL-FORMING BASED ON OBJECT ORIENTED PROGRAMMING

To simulate the process of cold roll-forming process, a new method isadopted. The theoretical foundation of this method is an elastic-plastic large deformation splinefinite strip method based on object-oriented programming. Combined with the computer graphicstechnology, the visual simulation of cold roll-forming is completed and the system is established.By analyzing common channel steel, the process is shown and explained including theory method, modeland result display. So the simulation system is already a kind of mature and effective tool toanalyze the process of cold roll forming.

Navigated liver surgery:State of the art and future perspectives

Background:In recent years,the development of digital imaging technology has had a significant influence in liver surgery.The ability to obtain a 3-dimensional(3D)visualization of the liver anatomy has provided surgery with virtual reality of simulation 3D computer models,3D printing models and more recently holograms and augmented reality(when virtual reality knowledge is superimposed onto reality).In addition,the utilization of real-time fluorescent imaging techniques based on indocyanine green(ICG)uptake allows clinicians to precisely delineate the liver anatomy and/or tumors within the parenchyma,applying the knowledge obtained preoperatively through digital imaging.The combination of both has transformed the abstract thinking until now based on 2D imaging into a 3D preoperative conception(virtual reality),enhanced with real-time visualization of the fluorescent liver structures,effectively facilitating intraoperative navigated liver surgery(augmented reality).Data sources:A literature search was performed from inception until January 2021 in MEDLINE(Pub Med),Embase,Cochrane library and database for systematic reviews(CDSR),Google Scholar,and National Institute for Health and Clinical Excellence(NICE)databases.Results:Fifty-one pertinent articles were retrieved and included.The different types of digital imaging technologies and the real-time navigated liver surgery were estimated and compared.Conclusions:ICG fluorescent imaging techniques can contribute essentially to the real-time definition of liver segments;as a result,precise hepatic resection can be guided by the presence of fluorescence.Furthermore,3D models can help essentially to further advancing of precision in hepatic surgery by permitting estimation of liver volume and functional liver remnant,delineation of resection lines along the liver segments and evaluation of tumor margins.In liver transplantation and especially in living donor liver transplantation(LDLT),3D printed models of the donor’s liver and models of the recipient’s hilar anatomy can contribute further to improving the results.In particular,pediatric LDLT abdominal cavity models can help to manage the largest challenge of this procedure,namely large-for-size syndrome.

INDUSTRIAL ENGINEERING AND VISUALISATION—A PRODUCT DEVELOPMENT PERSPECTIVE

Taking the actual project of teaching and researching process for example, the relationship between the industrial engineering and product development is discussed. And use the novel visualization technology to support the industrial engineering and product development. How to use the new computer modeling and simulating technologies to support the product development and industrial engineering, is introduced especially. The support includes both domestic products and industrial systems. The visualization and computer technologies take a very impo[tant role in some system or multi-direction modeling, those technologies mentioned above can help the industrial engineers study the effect of design on the whole life circle, including the producing steps. So the engineers can avoid making the wrong decision which may cause bad effects on the whole industrial engineering.

A Survey of Multi-Space Techniques in Spatio-Temporal Simulation Data Visualization

The widespread use of numerical simulations in different scientific domains provides a variety of research opportunities.They often output a great deal of spatio-temporal simulation data,which are traditionally characterized as single-run,multi-run,multi-variate,multi-modal and multi-dimensional.From the perspective of data exploration and analysis,we noticed that many works focusing on spatiotemporal simulation data often share similar exploration techniques,for example,the exploration schemes designed in simulation space,parameter space,feature space and combinations of them.However,it lacks a survey to have a systematic overview of the essential commonalities shared by those works.In this survey,we take a novel multi-space perspective to categorize the state-ofthe-art works into three major categories.Specifically,the works are characterized as using similar techniques such as visual designs in simulation space(e.g,visual mapping,boxplot-based visual summarization,etc.),parameter space analysis(e.g,visual steering,parameter space projection,etc.)and data processing in feature space(e.g,feature definition and extraction,sampling,reduction and clustering of simulation data,etc.).

AB033.The impact of visual impairment on the Montreal Cognitive Assessment

Background:Cognitive assessments,such as the Montreal Cognitive Assessment(MoCA),use components that assume intact sensory abilities,however,adults show concomitant decreases in visual acuity with increasing age.Scores on cognitive assessments are typically lower for individuals with visual impairments compared to individuals with normal/corrected to normal vision.But it is not clear if lowers scores on cognitive assessments are due to the assessments relying on visual stimuli,or if individuals with visual impairments are actually more likely to have cognitive impairments.Therefore we simulated visual impairments,i.e.,reduced visual acuity and contrast sensitivity,in young healthy adults to determine how this impacts their scores on a measure of cognitive ability,i.e.,the MoCA.Methods:Participants(n=19)completed one of the three version of the MoCA under three conditions(20/20,simulated 20/80,simulated 20/200).The MoCA was administered following the clinical protocols.Only participants that scored>26(i.e.,normal cognitive function)at 20/20 were included in the analysis.For comparison,we included MoCA data from a sample of older adults with normal vision(n=19,Mage=74,Acuity M=0.04 logMAR,SD=0.16)or visual impairment(n=19,Mage=79,Acuity M=0.35 logMAR,SD=0.3).Results:Acuity of participants at 20/20(M=0.06 LogMAR,SD=0.1),simulated 20/80(M=0.63,SD=0.18)and simulated 20/200(M=0.88,SD=0.19)showed that the participants experienced simulated acuity loss with the goggles.For the MoCA scores,we found a main effect of acuity(F=16.22,P<0.001,η2=0.375,BF10=5,618).Planned post hoc comparisons showed a significant difference between scores with a 20/20 acuity(M=27.26,SD=0.93)and 20/80(M=24.74,SD=1.66,t=5.62,ptukey<0.001,d=1.88),and between 20/20 and 20/200(M=25.63,SD=1.46,t=3.63,ptukey=0.002,Cohen’s d=1.33).However,no difference was observed between 20/80 and 20/200(t=−1.99,ptukey=0.125,d=0.572).The MoCA scores in older adults with normal vision(M=27.32,SD=2.41)and with visual impairment(M=26.68,SD=2.52),did not differ significantly(t36=−0.787,P=0.436,d=0.26,BF10=0.4).Conclusions:Our findings show that simulated reductions in visual acuity and contrast sensitivity lead to lower scores on measures of cognitive ability,specifically the MoCA.However,it appears that older adults with actual visual impairments may have developed compensatory strategies to adapt to this loss in visual acuity as there were no significant differences in scores of older adults with and without visual impairments.Therefore,we would recommend that when assessing an individual with visual impairments to conduct the cognitive test by re-scoring it without the visual components,e.g.,the MoCA Blind,to magnify the visual components,or to substitue the visual component when possible using auditory alternatives,e.g.,the oral trail making task.

Multi-Project in an Integrated BIM Model: Clash Detection and Construction Planning

The Building Information Modelling (BIM) methodology has been adopted in the construction industry, supporting the development of projects. Its implementation has improved the collaboration and integration in the design context, increasing the accuracy of the project preparation and the decreasing additional costs and delays of the construction work. The main objective of the present research is to provide an overview of the state of the art of BIM applications, namely, concerning the construction planning. For that, the generation of a BIM 3D model, involving the disciplines of architecture, structures and water supply system was performed. After, over the model a conflict analysis was applied, in order to verify the consistency of all the disciplines, when linked together. In order to obtain a visual simulation of the construction process, the correspondent 4D BIM model was also generated. Along the development of the study, distinct BIM software was applied over a case study. The main remarks of the capacities of the software, as well as the benefits and limitations verified were identified.

Water Resources Operation and Management Model and Its Simulation Process Research

Based on the status quantity of water resources in Xi′an region, a commentary on many math models is given for water resources operation and management, and the visual model is provided to solve practical problems. In this model, the information for decision is visible in GIS (Geographic Information Systems) and topological figures. With object orientation methods, the objects are described in proprieties, methods, relations and time periods. The simulation process of the model is developed with Delphi and MapInfo, and the real decision scheme could be examined and practice decision process can be simulated from which. Decision analysis conducted from visual conditions is believable. The exploration to visual model is a beginning of practice research, much more study of which still needs to do.

Deliberative Collision Avoidance for Unmanned Surface Vehicle Based on the Directional Weight

The purpose of this study is to realize the intelligent deliberative obstacle avoidance for unmanned surface vehicle(USV), based on the International Regulations for Preventing Collisions at Sea called COLREGS.Firstly, a three-level system architecture is designed for the ship intelligent collision avoidance system. Secondly,an intelligent collision avoidance algorithm is presented based on the calculation of motion parameters and the rules of COLREGS. Thirdly, according to COLREGS, the marine environment is modeled from the electronic chart data and radar information, and a deliberative collision avoidance algorithm is written. Finally, the deliberative collision avoidance simulation is carried out for the USV. The feasibility and reliability of intelligent collision avoidance algorithm are verified by the vivid simulation results.

InvesInvestigation of the Effects of Airfoil-probes on the Aerodynamic Performance of an Axial Compressor

In order to investigate the effects of the airfoil-probes on the aerodynamic performance of an axial compressor,a numerical simulation of 3D flow field is performed in a 1.5-stage axial compressor with airfoil-probes installed at the stator leading-edge（LE）.The airfoil-probes have a negative influence on the compressor aerodynamic performance at all operating points.A streamwise vortex is induced by the airfoil-probe along both sides of the blade.At the mid-operating point,the vortex is notable along the pressure side and is relatively small along the suction side（SS）.At the near-stall point,the vortex is slightly suppressed in the pressure surface（PS）,but becomes remarkable in the suction side.A small local-separation is induced by the interactions between the vortex and the end-wall boundary layer in the corner region near the hub.That the positive pitch angle of the airfoil-probe at 6.5% span is about 15° plays an important role in the vortex evolution near the hub,which causes the fact that the airfoil-probe near the hub has the largest effects among the four airfoil-probes.In order to get a further understanding of the vortex evolution in the stator in the numerical simulation,a flow visualization experiment in a water tunnel is performed.The flow visualization results give a deep insight into the evolution of the vortex induced by the airfoil-probe.

Theory and Practice of the Stereo-View on the CRT Screen

Of the various kinds of research on the Virtual Reality and GIS, stereo-view is one of the key technologies . The following two aspects are covered in this paper. (1)Physiological fundamental of the natural binocular stereo-vision, theory of 3D color TV and the stereo-view on the CRT screen are presented, especially the theory of widely adopted Time-Division System is introduced. (2) The preliminary practice for using the sterecrview technology on the screen to the terrain visual simulation is described, and the paper shows how to use 3DS to construct a movable real stereo terrain perspective by taking DTM data as the first hand information for the purpose of terrain visual simulation.