A practical method of constructing surfaces in three-dimensional digitized space

1987 ◽  
Vol 3 (1) ◽  
pp. 4-12 ◽  
Author(s):  
Ken-ichi Anjyo ◽  
Toshio Ochi ◽  
Yoshiaki Usami ◽  
Yasumasa Kawashima
Keyword(s):  
Three Dimensional ◽  
Practical Method

scholarly journals Determination of the Optimal Syndesmosis Fixation Angle Using Mortise View of The Ankle Joint

2021 ◽  
Author(s):  
Oğuzhan Tanoğlu ◽  
İzzet Özay Subaşı ◽  
Mehmet Burak Gökgöz
Keyword(s):  
Ankle Joint ◽  
Articular Surface ◽  
Three Dimensional ◽  
Vertical Plane ◽  
Functional Results ◽  
Practical Method ◽  
Medial Malleolus ◽  
Significant Difference ◽  
Horizontal View ◽  
Mortise View

Background: Syndesmosis is an important soft tissue component supporting the ankle stability and commonly injured accompanying with ankle fractures. The accurate reduction and fixation of syndesmosis is essential to obtain better functional results. Therefore, we aimed to find a practical method using the mortise view of ankle to determine the optimal syndesmosis fixation angle intraoperatively. Methods: We randomly selected 200 adults (100 women and 100 men) between 18 - 60 years of age. Three-dimensional anatomical models of tibia and fibula were created using Materialise MIMICS 21. We created a best fit plane on articular surface of medial malleolus and a ninety degrees vertical plane to medial malleolus plane. We determined two splines on cortical borders of tibia and fibula distant from the most superior point of ankle joint in horizontal view. We created two spheres that fit to the predefined splines. The optimal syndesmosis fixation angle was determined measuring the angle between the line connecting the center points of spheres, and the ninety degrees vertical plane to medial malleolus plane. Results: We observed no statistically significant difference between gender groups in terms of optimal syndesmosis fixation angles. The mean age of our study population was 47.1 {plus minus} 10.5. The optimal syndesmosis fixation angle according to mortise view was found as 21 {plus minus} 4.3 degrees. Conclusions: We determined the optimal syndesmosis fixation angle as 21 {plus minus} 4.3 degrees in accordance with the mortise view of ankle. The surgeon could evaluate the whole articular surface of ankle joint with the medial and lateral syndesmotic space in mortise view accurately and at the same position syndesmosis fixation could be performed at 21 {plus minus} 4.3 degrees.

RTD (residence time distribution) predictions in large mechanically aerated lagoons

2007 ◽  
Vol 55 (11) ◽  
pp. 29-36 ◽  
Author(s):  
D. Stropky ◽  
K. Pougatch ◽  
P. Nowak ◽  
M. Salcudean ◽  
P. Pagoria ◽  
...  
Keyword(s):  
Paper Industry ◽  
Three Dimensional ◽  
Field Measurements ◽  
Particle Method ◽  
Practical Method ◽  
Hydraulic Performance ◽  
Computational Time ◽  
Complex Flow ◽  
Mechanical Agitation ◽  
Sludge Accumulation

Mechanically aerated lagoons (used for wastewater treatment in the pulp and paper industry) are typically very large (>500,000 m3) and have complex three-dimensional fluid flow patterns due to mechanical agitation, sludge accumulation, internal baffling, and confined inlet/outlet flow channels. RTD data is frequently used for evaluation of hydraulic performance. however, obtaining accurate data with traditional dye measurements is a difficult and time-consuming process. Moreover, the mixing impact of factors such as aerator positions, sludge accumulation, and internal baffles would require a significant and costly number of local field measurements. Recent applications of CFD to mechanically aerated lagoons have helped engineers to understand the complex flow interactions. This paper provides a practical method for the evaluation of the hydraulic performance of large mechanically aerated lagoons using CFD. A method, based on random-walk Lagrangian particle tracking, has been developed to significantly shorten the computational time needed to produce RTD curves for these lagoons. Comparison of the particle method with the more conventional scalar transport yields excellent results. These methods allow wastewater engineers to combine their existing knowledge and expertise with the established power of CFD. The results quantify the hydraulic impact of different inlet/outlet configurations, aerator configurations, influent flow rates, and bottom sludge profiles.

Visual Plant Sticks Growth Model and Three-Dimensional Visualization

2014 ◽  
Vol 1049-1050 ◽  
pp. 1347-1350
Author(s):  
Ying Ying Yin ◽  
Li Fei Chen
Keyword(s):  
Growth Model ◽  
Growth Process ◽  
Three Dimensional ◽  
Plant Morphology ◽  
Practical Method ◽  
Effective Model ◽  
Plant Weight ◽  
Virtual Plant ◽  
Simulation Results ◽  
The Relationship

For the aim that describing the growth process of plant sticks with a effective model, presented a new method based on plant physiological characteristics, it also considered plant weight and light comprehensively. The model can reflect parallel growing of plants continually and dynamically, and the relationship between plant morphology and growing physiology is also be reflected at the same time. The simulation results show that the model is directly and provides a practical method for the research of virtual plant, especially for the plant sticks.

scholarly journals Determination of Some Body Measurements of Camels With Three Dimensional Modeling Method (3D)

2021 ◽  
Author(s):  
Alkan çağlı ◽  
M. Yılmaz
Keyword(s):  
Large Scale ◽  
Three Dimensional ◽  
Practical Method ◽  
Modeling Method ◽  
The Body ◽  
Body Measurements ◽  
3D Measurement ◽  
Three Dimensional Modeling ◽  
Dimensional Modeling ◽  
The Difference

Abstract In this study, the use of three-dimensional modeling method was tested in taking some body measurements in camels with a practical method and was compared with other measurement methods. As the animal material of the study, 12 single humped dromedary female camels and 14 double humped Camelus dromedarius X Camelus bactrianus: F1 male camels, totally 26 camels, were used in three camel farms in Incirliova district of Aydın province. The body measurements taken from each animal by using different three methods, namely by Manuel Method (MM), by Photography Method (PM), and by Three Dimensional Modeling Method (3D) were the Cidago Height (CH), the Back Height (BH), the Rump Height (RH), the Body Length (BL), the Brisket Height (BRH), the Abdominal Height (AH), the Shoulder Width (SW) and the Rump Width (RW) and these values were compared with each other. As a result of this study, the mean values of MM and 3D measurement values were very close to each other and the difference between them was found to be statistically insignificant. (P<0.05). The difference between the means of PM and MM/3D measurement values was found to be significant. (P <0.05). In the measurements taken by MM, 3D, PM methods in male camels, the values obtained by MM and 3D methods for CH, BH, RH, BRH, AH, BL, and SW were very close to each other and the differences between them were found insignificant statistically (p < 0.05). On the determined regression graph, a linear was found between MM and 3D measurement values. As a result of this study, it has been determined that the 3D modeling method can be used as a remote and more practical method in determining the morphological features of large-scale animals such as camels more reliably, more easily and more practically.

scholarly journals Three-dimensional orthotropic nonlinear transient moisture simulation for wood: analysis on the effect of scanning curves and nonlinearity

2020 ◽  
Vol 54 (5) ◽  
pp. 1197-1222 ◽  
Author(s):  
Sara Florisson ◽  
Johan Vessby ◽  
Winston Mmari ◽  
Sigurdur Ormarsson
Keyword(s):  
Mechanical Behaviour ◽  
Moisture Transport ◽  
Three Dimensional ◽  
Boundary Surface ◽  
Neumann Boundary ◽  
Practical Method ◽  
Analysis Tool ◽  
Surface Emission ◽  
Finite Element Software ◽  
Scanning Curves

Abstract This paper introduces, with the development of user-subroutines in the finite-element software Abaqus FEA®, a new practical analysis tool to simulate transient nonlinear moisture transport in wood. The tool is used to revisit the calibration of moisture simulations prior to the simulation of mechanical behaviour in bending subjected to climate change. Often, this calibration does not receive sufficient attention, since the properties and mechanical behaviour are strongly moisture dependent. The calibration of the moisture transport simulation is made with the average volumetric mass data experimentally obtained on a paired specimen of Norway spruce (Picea abies) with the dimensions $$30\times 15\times 640\, {\mathrm{mm}}^{3}$$ 30 × 15 × 640 mm 3 . The data, from a 90-day period, were measured under a constant temperature of 60 °C and systematic relative humidity cycles between 40 and 80%. A practical method based on analytical expressions was used to incorporate hysteresis and scanning behaviour at the boundary surface. The simulation tool makes the single-Fickian model and Neumann boundary condition readily available and the simulations more flexible to different uses. It also allows for a smoother description of inhomogeneity of material. The analysis from the calibration showed that scanning curves associated with hysteresis cannot be neglected in the simulation. The nonlinearity of the analysis indicated that a coherent set of moisture dependent diffusion and surface emission coefficient is necessary for the correct description of moisture gradients and mass transport.

The Cosserat Spectrum Theory in Thermoelasticity and Application to the Problem of Heat Flow Past a Rigid Spherical Inclusion

1998 ◽  
Vol 65 (3) ◽  
pp. 614-618 ◽  
Author(s):  
Wensen Liu ◽  
X. Markenscoff ◽  
M. Paukshto
Keyword(s):  
Variational Principle ◽  
Heat Flow ◽  
Displacement Field ◽  
Elastic Energy ◽  
Rigid Inclusion ◽  
Spherical Inclusion ◽  
Three Dimensional ◽  
Practical Method ◽  
Cosserat Spectrum ◽  
Thermoelastic Displacement

We apply the Cosserat Spectrum theory to boundary value problems in thermoelasticity and show the advantages of this method. The thermoelastic displacement field caused by a general heat flow around a spherical rigid inclusion is calculatedand the results show that the discrete Cosserat eigenfunctions converge fast and thus provide a practical method for solving three-dimensional problems in thermoelasticity. In the case of uniform heat flow, the solution is obtained analytically in closed form and a variational principle within the frame of the Cosserat Spectrum theory shows that the solution maximizes the elastic energy.

Mitigation of Vertical and Horizontal Seismic Excitations on Bridges Utilizing Shape Memory Alloy System

2013 ◽  
Vol 831 ◽  
pp. 90-94 ◽  
Author(s):  
H. Aryan ◽  
M. Ghassemieh
Keyword(s):  
Shape Memory Alloy ◽  
Shape Memory ◽  
Three Dimensional ◽  
Time History ◽  
Alloy System ◽  
Practical Method ◽  
Nonlinear Time History Analysis ◽  
Vertical Acceleration ◽  
Three Dimensional Model ◽  
Seismic Excitations

Vertical seismic excitation has a tremendous effect on bridges and many researchers have pointed out bridges damages occurred during the past significant earthquakes which were direct results of ignoring vertical acceleration of ground motions. Many studies have emphasized the importance of extending practical methods to reduce effects of vertical acceleration of earthquakes besides effects of horizontal accelerations; but no practical method has proposed up to now. In this article, an innovative shape memory alloy system is proposed for bridges that can simultaneously controls effects of vertical and horizontal seismic excitations on bridge and reduce them. To evaluate the effectiveness of the shape memory alloy system, a nonlinear time history analysis is conducted on a detailed three-dimensional model of a multi-span simply supported bridge using a representative ground motion. The results show that the proposed new system is very effective for reducing effects of vertical and horizontal seismic excitations on bridges.

scholarly journals PSD Analysis and Optimization of 2500hp Shale Gas Fracturing Truck Chassis Frame

2014 ◽  
Vol 8 (1) ◽  
pp. 533-538
Author(s):  
Han-Xiang Wang ◽  
De-Xin Yuan ◽  
Li-Jun Zhang ◽  
Fan Zhang
Keyword(s):  
Fatigue Strength ◽  
Shale Gas ◽  
Random Vibration ◽  
Three Dimensional ◽  
Practical Method ◽  
Random Excitation ◽  
Three Dimensional Model ◽  
Element Analysis ◽  
Spectrum Density ◽  
Truck Chassis

The three-dimensional model of 2500hp shale gas fracturing truck chassis frame was established and the natural frequency of the frame was obtained by modal analysis. Taking the displacement power spectrum density of a typical road as a random excitation, the random vibration response of frame was obtained by PSD module of finite element analysis software ANSYS. Based on the results of PSD analysis, the frame’s fatigue characteristic under random vibration condition was studied according to Gauss distribution theory and Miner fatigue cumulative damage law, and the random fatigue strength of the frame was also calculated and optimized as well. A reliable and practical method was provided to verify the fatigue strength and to predict fatigue life of fracturing truck chassis frame. The conclusion provides an important theoretical reference for optimization of the frame.

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