Application of Three-Dimensional Visualization Technology in Project Management of Offshore Platform Engineering Construction

Three-dimensional visualization technology converts engineering design drawings and data into graphics or images, realizes virtual reality perception of simulated users in future construction scene, enhances the interaction between project management and technical personnel and engineering construction achievement, and provides intuitive, flexible and strong realistic experience for project management. It can effectively improve the level of project communication, and assist the needs of project construction planning management, training, exhibition, etc. As a tool to help improve project management skills, it has good application effect and prospects.

Analysis on Discourse Construction of HK Riots between HK Protesters and China's Mainland Media Based on Fairclough’s Three-dimensional Framework of Critical Discourse Analysis

The Critical Discourse Analysis(CDA)is an interdisciplinary tool in various conditions,which aims to provide a better understanding of sociocultural aspects of texts and accounts of the production of internal structure,and overall organization of texts as well as to provide a critical dimension in its theoretical and descriptive accounts of texts.Since June last year,HK protests or HK violence have been frequently reported by worldwide media.In this paper,the author aims to find out how the HK protesters and the Mainland media describe the same event based on the three-dimensional framework of CDA.At last,the author concludes that the mainland media generally describe the event as violence and riot while the HK protesters define themselves as warriors striving for more freedom,justice and democracy.Besides,on this event,the Mainland media mainly accuses some western countries of interference into HK affairs,which is undoubtedly of China’s internal affairs,and the media give full support to the HK police in safeguarding the peace and stability of Hong Kong.But from the perspective of HK protesters,they firmly believe that they are using their actions to protect all the people of HK,and they are defending their values such as freedom,democracy and justice.These are two totally different systems of language,and the author also gives its potential reasons in the paper so as to offer some viewpoints in this aspect in combination with the CDA theory.

Construction of three-dimensional atlas of the lenticular nuclei and its subnucleus based on the cryosection images from Chinese visible human:a preliminary study

Objective To establish a 3D atlas of the lenticular nuclei and its subnucleus with the cryosection images of the male from "Atlas of Chinese Visible Human". Methods The lenticular nuclei and its subnucleus were segmented from the cryosection images and reconstructed with the software

Constructal design of a rectangular parallel phase change microchannel in a three-dimensional electronic device

Based on constructal theory,a rectangular parallel phase change microchannel model in a three-dimensional electronic device(TDED)is established with R134a as the cooling fluid.Based on the minimization of a complex function(CF)composed of linear weighting sum of maximum temperature difference and pumping power consumption,constructal design of the TDED is conducted first;and then,maximum temperature difference and pumping power consumption are minimized by non-dominated sorting genetic algorithm-II methods.The results reveal that there exist an optimal mass flow rate(0.0012 kg/s)and a quadratic optimal aspect ratio(AR)(0.39)of the microchannel which lead to quadratic minimum CF(0.817).Compared with the original value,the CF after optimization is reduced by 18.34%.Reducing the inlet temperature of cooling fluid and microchannel number appropriately can help to enhance the overall performance of TDED.By using the artificial neural network and genetic algorithms in the toolboxes of Matlab software,the optimal AR gained in the Pareto solution set is located between 0.2–0.45.The smallest deviation index among three discussed strategies is 0.346,and the corresponding optimal AR is 0.413,which is selected as the optimal design strategy of the microchannel in the TDED under multiple requirements.The findings in this study can serve as theoretical guides for thermal designs of electronic devices.

Evaluation of Tubal Patency with Transvaginal Three-dimensional Hysterosalpingo-contrast Sonography

Objective To investigate diagnostic efficacy of transvaginal three-dimensional hysterosalpingo-contrast sonography(3D-Hy Co Sy) in assessing tubal patency with chromolaporoscopy. Methods A total of 157 infertile women underwent 3D-Hy Co Sy to evaluate tubal patency. Among these patients, 39 patients were also examined by chromolaporoscopy. The concordance of the two clinical assessment methods was analyzed by the Kappa coefficient test. Results Among the 306 oviducts examined by 3D-Hy Co Sy, 99(32.4%) were patent, 126(41.2%) partially obstructed, and 81(26.5%) completely obstructed. Diagnostic results with 3D-Hy Co Sy were not statistically different from those obtained in the 39 women(78 oviducts) who also underwent chromolaporoscopy, and the two methods showed a high concordance(κ=0.747, P=0.000). The 3D-Hy Co Sy procedure had a sensitivity of 84.8%(28/33), a specificity of 96.2%(25/26), and positive and negative predictive values of 93.3%(28/30) and 86.2%(25/29) respectively. Conclusion Transvaginal 3D-Hy Co Sy can accurately reveal the spatial path and morphology of the oviduct and is a safe and effective method to evaluate tubal patency.

Research on the Three-dimensional Modeling and Optimization of a Virtual Tower Crane Based on 3DS Max, Solidworks and EON Professional

Three-dimensional modeling of virtual hoisting machinery is the critical works to structure the system of virtual construction, and the foundation to realize intelligent and interactive virtual hoisting. Aimed at enhancing the requests of image quality and stability of the virtual construction scene, taking a tower crane for example. We studied the technology of three-dimensional modeling and optimization of a virtual tower crane, and a method named two-stage model optimization was put forward. This depended on the modeling stage using Solidworks and 3DS Max and the performance optimization stage in EON. The practice of software development indicates that the proposed methods of three-dimensional modeling and optimization could satisfy the performance request of virtual construction system and be popularized to other virtual system.

“Volume-point” heat conduction constructal optimization based on entransy dissipation rate minimization with three-dimensional cylindrical element and rectangular and triangular elements on microscale and nanoscale

Based on constructal theory,the constructs of three "volume-point" heat conduction models with three-dimensional cylindrical element and rectangular and triangular elements on microscale and nanoscale are optimized by taking minimum entransy dissipation rate as optimization objective.The optimal constructs of the three "volume-point" heat conduction models with minimum dimensionless equivalent thermal resistance are obtained.The results show that the optimal constructs of the three-dimensional cylindrical assembly based on the minimizations of dimensionless equivalent thermal resistance and dimensionless maximum thermal resistance are different,which is obviously different from the comparison between those of the corresponding two-dimensional rectangular assembly based on the minimizations of these two objectives.The optimal constructs based on rectangular and triangular elements on microscale and nanoscale when the size effect takes effect are obviously different from those when the size effect does not take effect.Because the thermal current density in the high conductivity channel of the rectangular and triangular second order assemblies are not linear with the length,the optimal constructs of these assemblies based on the minimization of entransy dissipation rate are different from those based on the minimization of maximum temperature difference.The dimensionless equivalent thermal resistance defined based on entransy dissipation rate reflects the average heat transfer performance of the construct.The studies on "volume-point" heat conduction constructal problems at three-dimensional conditions and microscale and nanoscale by taking minimum entransy dissipation rate as optimization objective extend the application range of the entransy dissipation extremum principle.

Scanning electron microscopic observation:three-dimensional architecture of the collagen in hepatic fibrosis rats

Background In the process of hepatic fibrosis, the accumulation of collagen fibers is strongly related to the hepatic function. The aim of this study was to investigate the three-dimensional architecture of the collagen network in the liver of rats with hepatic fibrosis. Methods Healthy adult male Wistar rats （n=32） were randomly divided into a control group （n=16） and a hepatic fibrosis group （n=16）. In the control group, the rats were treated with peanut oil while the rats in hepatic fibrosis group were treated for 10 weeks with 60% CCI4 diluted in peanut oil. The quantity of collagen fibers was detected by Western blotting; distribution of the collagen was detected by sirius red staining and polarized microscope; the three-dimensional architecture of collagen in the liver was observed under the scanning electron microscope after fixed tissues were treated with cell-maceration using NaOH. Statistical analysis was performed using the u test. Results The quantity of collagen fibers increased significantly in the hepatic fibrosis group. With the aggravation of hepatic fibrosis, collagen fibers gradually accumulated. They interlaced the reticulation compartment and formed a round or ellipse liver tissue conglomeration like a grape framework that was disparate and wrapped up the normal liver Iobule. The deposition of collagen fibers was obvious in adjacent hepatic parenchyma, especially around the portal tracts. Conclusion Our experiment showed the collagen proliferation and displays clearly the three-dimensional architecture of collagen fibers in rat liver with hepatic fibrosis by scanning electron microscope. It can provide a morphological foundation for the mechanisms of changed haemodynamics and portal hypertension in hepatic fibrosis.

Research on an Integrated Modeling Method of Virtual Ship Assembly

A new method of virtual ship assembly modeling which integrates ship three-dimensional design and ship construction planning was described in this paper. A workflow model of simulation modeling based on the virtual ship assembly process was also established; furthermore, a method of information transformation between the ship three-dimensional design and ship construction plan was formulated. To meet the requirements of information sharing between different systems in the ship virtual assembly, a simulation database was created by using the software engineering design method and the relational data model. With the application of this database, the information of ship three-dimensional design, construction planning, and virtual assembly can be integrated into one system. Subsequently, this new method was applied as a tool to simulate the virtual assembly of a ship, and the results guarantee its rationality and reliability.

Study on the computation method of temperature field of RCC dam

According to the construction characteristic of RCC dam cast by layers, three-dimensional finite element relocating mesh method is developed to simulate construction process and compute temperature field. The computation model of relocating mesh method is expatiated in detail; based on the thermodynamic properties of RCC materials, the feasibility and error of relocating mesh method are analyzed and demonstrated; The computation results in this article are verified by means of the temperature observation data of certain RCC gravity dam. The results show that the temperature field computed by three-dimensional finite element relocating mesh method can not only ensure the computation precision, but also improve the calculation efficiency greatly. This provides an effective method for simulating construction process and computing temperature field of RCC dam.

Discussion and study on contraction joints for RCC gravity dam

Based on the construction property of rolled compacted concrete, three-dimensional finite element relocating mesh method was developed in simulating construction process and computing temperature and stress field. Using this method, the temperature and the thermal stress fields developed in the RCC gravity dam of the Longtan project with or without a longitudinal joint during construction and operation are calculated so as to simulate the construction process. The computation results show that the value of the thermal stresses developed in the dam even, without any longitudinal joint, could meet the design criteria provided the placement temperature is adequately controlled.

Constructal optimization of cylindrical heat sources with forced convection based on entransy dissipation rate minimization

Based on constructal theory and entransy theory,the optimal designs of constant-and variable-cross-sectional cylindrical heat sources are carried out by taking dimensionless equivalent resistance minimization as optimization objective.The effects of the cylindrical height,the cylindrical shape and the ratio of thermal conductivity of the fin to that of the heat source are analyzed.The results show that when the volume of the heat source is fixed,there exists an optimal ratio of the center-to-centre distance of the fin and the heat source to the cylinder radius which leads to the minimum dimensionless equivalent thermal resistance.With the increase in the height of the cylindrical heat source and the ratio of thermal conductivity,the minimum dimensionless equivalent thermal resistance decreases gradually.For the heat source model with inverted variable-cross-sectional cylinder,there exist an optimal ratio of the center-to-centre distance of the fin and the heat source to the cylinder radius and an optimal radius ratio of the smaller and bigger circles of the cylindrical fin which lead to a double minimum dimensionless equivalent thermal resistance.Therefore,the heat transfer performance of the cylindrical heat source is improved by adopting the cylindrical model with variable-cross-section.The optimal constructs of the cylindrical heat source based on the minimizations of dimensionless maximum thermal resistance and dimensionless equivalent thermal resistance are different.When the thermal security is ensured,the optimal construct of the cylindrical heat source based on minimum equivalent thermal resistance can provide a new alternative scheme for the practical design of heat source.The results obtained herein enrich the work of constructal theory and entransy theory in the optimal design field of the heat sources,and they can provide some guidelines for the designs of practical heat source systems.