A three-dimensional isolation floor for earthquake and ambient micro-vibration using multi-stage rubber bearings. (2nd Report, Development of a new device for vertical isolation).

In a joint project between the Institute of Aircraft Propulsion Systems (ILA) and MTU Aero Engines a two-stage low pressure turbine is tested at design and strong off-design conditions. The experimental data taken in the altitude test-facility aims to study the effect of positive and negative incidence of the second stator vane. A detailed insight and understanding of the blade row interactions at these regimes is sought. Steady and time-resolved pressure measurements on the airfoil as well as inlet and outlet hot-film traverses at identical Reynolds number are performed for the midspan streamline. The results are compared with unsteady multi-stage CFD predictions. Simulations agree well with the experimental data and allow detailed insights in the time-resolved flow-field. Airfoil pressure field responses are found to increase with positve incidence whereas at negative incidence the magnitude remains unchanged. Different pressure to suction side phasing is observed for the studied regimes. The assessment of unsteady blade forces reveals that changes in unsteady lift are minor compared to changes in axial force components. These increase with increasing positive incidence. The wake-interactions are predominating the blade responses in all regimes. For the positive incidence conditions vane 1 passage vortex fluid is involved in the midspan passage interaction leading to a more distorted three-dimensional flow field.

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Inverse Design of 3D Multi-Stage Transonic Fans at Dual Operating Points

Volume 6B: Turbomachinery ◽

10.1115/gt2013-95062 ◽

2013 ◽

Cited By ~ 2

Author(s):

James H. Page ◽

Paul Hield ◽

Paul G. Tucker

Keyword(s):

Design Method ◽

Pressure Ratio ◽

Three Dimensional ◽

Inverse Design ◽

Flow Angle ◽

Trade Offs ◽

Multi Stage ◽

Full Speed ◽

Computational Fluid Dynamics Cfd ◽

Operating Points

Semi-inverse design is the automatic re-cambering of an aerofoil, during a computational fluid dynamics (CFD) calculation, in order to achieve a target lift distribution while maintaining thickness, hence “semi-inverse”. In this design method, the streamwise distribution of curvature is replaced by a stream-wise distribution of lift. The authors have developed an inverse design code based on the method of Hield (2008) which can rapidly design three-dimensional fan blades in a multi-stage environment. The algorithm uses an inner loop to design to radially varying target lift distributions, an outer loop to achieve radial distributions of stage pressure ratio and exit flow angle, and a choked nozzle to set design mass flow. The code is easily wrapped around any CFD solver. In this paper, we describe a novel algorithm for designing simultaneously for specified performance at full speed and peak efficiency at part speed, without trade-offs between the targets at each of the two operating points. We also introduce a novel adaptive target lift distribution which automatically develops discontinuous changes of calculated magnitude, based on the passage shock, eliminating erroneous lift demands in the shock vicinity and maintaining a smooth aerofoil.

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TightCap: 3D Human Shape Capture with Clothing Tightness Field

ACM Transactions on Graphics ◽

10.1145/3478518 ◽

2022 ◽

Vol 41 (1) ◽

pp. 1-17

Author(s):

Xin Chen ◽

Anqi Pang ◽

Wei Yang ◽

Peihao Wang ◽

Lan Xu ◽

...

Keyword(s):

Three Dimensional ◽

Ground Truth ◽

Data Driven ◽

Optimization Scheme ◽

High Quality ◽

3D Scan ◽

Multi Stage ◽

Geometry Image

In this article, we present TightCap, a data-driven scheme to capture both the human shape and dressed garments accurately with only a single three-dimensional (3D) human scan, which enables numerous applications such as virtual try-on, biometrics, and body evaluation. To break the severe variations of the human poses and garments, we propose to model the clothing tightness field—the displacements from the garments to the human shape implicitly in the global UV texturing domain. To this end, we utilize an enhanced statistical human template and an effective multi-stage alignment scheme to map the 3D scan into a hybrid 2D geometry image. Based on this 2D representation, we propose a novel framework to predict clothing tightness field via a novel tightness formulation, as well as an effective optimization scheme to further reconstruct multi-layer human shape and garments under various clothing categories and human postures. We further propose a new clothing tightness dataset of human scans with a large variety of clothing styles, poses, and corresponding ground-truth human shapes to stimulate further research. Extensive experiments demonstrate the effectiveness of our TightCap to achieve the high-quality human shape and dressed garments reconstruction, as well as the further applications for clothing segmentation, retargeting, and animation.

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UAV Path Planning Based on Multi-Stage Constraint Optimization

Drones ◽

10.3390/drones5040144 ◽

2021 ◽

Vol 5 (4) ◽

pp. 144

Author(s):

Yong Shen ◽

Yunlou Zhu ◽

Hongwei Kang ◽

Xingping Sun ◽

Qingyi Chen ◽

...

Keyword(s):

Path Planning ◽

Three Dimensional ◽

Evolutionary Process ◽

Constraint Processing ◽

Multi Stage ◽

Planning Ability ◽

Path Constraints ◽

Aerial Vehicle ◽

Multi Level ◽

Processing Mechanism

Evolutionary Algorithms (EAs) based Unmanned Aerial Vehicle (UAV) path planners have been extensively studied for their effectiveness and high concurrency. However, when there are many obstacles, the path can easily violate constraints during the evolutionary process. Even if a single waypoint causes a few constraint violations, the algorithm will discard these solutions. In this paper, path planning is constructed as a multi-objective optimization problem with constraints in a three-dimensional terrain scenario. To solve this problem in an effective way, this paper proposes an evolutionary algorithm based on multi-level constraint processing (ANSGA-III-PPS) to plan the shortest collision-free flight path of a gliding UAV. The proposed algorithm uses an adaptive constraint processing mechanism to improve different path constraints in a three-dimensional environment and uses an improved adaptive non-dominated sorting genetic algorithm (third edition—ANSGA-III) to enhance the algorithm’s path planning ability in a complex environment. The experimental results show that compared with the other four algorithms, ANSGA-III-PPS achieves the best solution performance. This not only validates the effect of the proposed algorithm, but also enriches and improves the research results of UAV path planning.

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Three-dimensional base-isolation system using thick rubber bearings

10.1117/12.916965 ◽

2012 ◽

Author(s):

T. Wang ◽

F. Wang

Keyword(s):

Base Isolation ◽

Three Dimensional ◽

Isolation System ◽

Base Isolation System ◽

Rubber Bearings

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Echocardiographic considerations during deployment of the Helex Septal Occluder for closure of atrial septal defects

Cardiology in the Young ◽

10.1017/s1047951103000556 ◽

2003 ◽

Vol 13 (3) ◽

pp. 290-298 ◽

Cited By ~ 8

Author(s):

Leo Lopez ◽

Roque Ventura ◽

Elizabeth M. Welch ◽

David G. Nykanen ◽

Evan M. Zahn

Keyword(s):

Three Dimensional ◽

Intracardiac Echocardiography ◽

New Device ◽

Septal Defects ◽

Acoustic Interference ◽

Atrial Septal Defects ◽

Helex Septal Occluder ◽

Interventional Catheterization

The Helex Septal Occluder is a new device used to close atrial septal defects via interventional catheterization. In order to study the role of echocardiography during its use, and to describe the morphologic variants of defects suitable for closure with this occluder, we evaluated all patients undergoing intended closure of an atrial septal defect with the Helex occluder. A combination of transthoracic, transesophageal, three-dimensional, and intracardiac echocardiography were used before, during, and after the procedure to characterize anatomy, assess candidacy for closure, guide the device during its deployment, and evaluate results. Among the 60 candidates included in the study, 11 were excluded because of transesophageal echocardiographic and/or catheterization data obtained in the laboratory. Attempts at closure were successful in 46 patients, and unsuccessful in 3. We successfully treated four types of defects. These were defects positioned centrally within the oval fossa with appreciable rims along the entire circumference of the defect, defects with deficient or absent segments of the rim, defects with aneurysm of the primary atrial septum, and defects with multiple fenestrations. Follow-up transthoracic echocardiograms taken at a median of 7 months demonstrated no residual defects in 21, trivial residual defects in 17, and small residual defects in 8 patients. In 20 patients, three-dimensional reconstructions were used to characterize the morphology of the defect and the position of the device. Because transesophageal echocardiography was often limited by acoustic interference from the device, intracardiac echocardiography was utilized in 3 cases to overcome this limitation.

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The environmental product variety and retail rents on central urban shopping areas: A multi-stage spatial data mining method

Environment and Planning B Urban Analytics and City Science ◽

10.1177/2399808320966607 ◽

2020 ◽

pp. 239980832096660

Author(s):

Tony Shun-Te Yuo ◽

Tzuhui Angie Tseng

Keyword(s):

Spatial Data ◽

Diversity Index ◽

Three Dimensional ◽

Product Variety ◽

Spatial Data Mining ◽

The Core ◽

Point Of Interest ◽

Number Of Layers ◽

Multi Stage ◽

The Relationship

This study examines the relationship between various measures of environmental product variety and retail rents in central urban shopping areas. Using a Geographic Information System (GIS)-based detailed survey database, this research identified 34 layers of environmental product variety in the most representative single-centred shopping areas of the six largest cities in Taiwan. This research extracted layers of product variety and other measures of product variety, such as the number of layers of product variety above each point of interest, the density, the Core/Periphery factor scores, the Shannon entropy index, the Simpson diversity index and the Herfindahl–Hirschman index of each street line buffer area. The proposed method was used to generate three-dimensional maps of the rent gradient and the extracted core and periphery layers of product variety. Thus, a tool was developed for examining the variety features from various angles. The results showed that, in general, the higher the product variety, the higher the rents. Nevertheless, the scores for the core and periphery of the environmental product variety were the dominant determinants; street line buffer areas can only have lower rents if they lacked the correct (i.e. the core layers) environmental product variety, even if they have higher measurements of other variety features.

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