scholarly journals A Topology-Preserving Simplification Method for 3D Building Models

2021 ◽  
Vol 10 (6) ◽  
pp. 422
Author(s):  
Biao Wang ◽  
Guoping Wu ◽  
Qiang Zhao ◽  
Yaozhu Li ◽  
Yiyuan Gao ◽  
...  
Keyword(s):  
Traditional Method ◽  
Boundary Vertex ◽  
Quadratic Error ◽  
Independent Components ◽  
Building Models ◽  
Series Of Experiments ◽  
Error Metric ◽  
Component Models ◽  
Different Levels ◽  
Separation Of Components

Simplification of 3D building models is an important way to improve rendering efficiency. When existing algorithms are directly applied to simplify multi-component models, generally composed of independent components with strong topological dependence, each component is simplified independently. The consequent destruction of topological dependence can cause unreasonable separation of components and even result in inconsistent conclusions of spatial analysis among different levels of details (LODs). To solve these problems, a novel simplification method, which considers the topological dependence among components as constraints, is proposed. The vertices of building models are divided into boundary vertices, hole vertices, and other ordinary vertices. For the boundary vertex, the angle between the edge and component (E–C angle), denoting the degree of component separation, is introduced to derive an error metric to limit the collapse of the edge located at adjacent areas of neighboring components. An improvement to the quadratic error metric (QEM) algorithm was developed for the hole vertex to address the unexpected error caused by the QEM’s defect. A series of experiments confirmed that the proposed method could effectively maintain the overall appearance features of building models. Compared with the traditional method, the consistency of visibility analysis among different LODs is much better.

scholarly journals AUTOMATIC RECONSTRUCTION OF ROOF MODELS FROM BUILDING OUTLINES AND AERIAL IMAGE DATA

2019 ◽  
Vol 59 (5) ◽  
pp. 448-457
Author(s):  
Vojtěch Hron ◽  
Lena Halounová
Keyword(s):  
Image Data ◽  
Aerial Survey ◽  
Aerial Image ◽  
Surface Model ◽  
Digital Surface Model ◽  
Multiple Datasets ◽  
Building Models ◽  
The Creation ◽  
Near Future ◽  
Different Levels

The knowledge of roof shapes is essential for the creation of 3D building models. Many experts and researchers use 3D building models for specialized tasks, such as creating noise maps, estimating the solar potential of roof structures, and planning new wireless infrastructures. Our aim is to introduce a technique for automating the creation of topologically correct roof building models using outlines and aerial image data. In this study, we used building footprints and vertical aerial survey photographs. Aerial survey photographs enabled us to produce an orthophoto and a digital surface model of the analysed area. The developed technique made it possible to detect roof edges from the orthophoto and to categorize the edges using spatial relationships and height information derived from the digital surface model. This method allows buildings with complicated shapes to be decomposed into simple parts that can be processed separately. In our study, a roof type and model were determined for each building part and tested with multiple datasets with different levels of quality. Excellent results were achieved for simple and medium complex roofs. Results for very complex roofs were unsatisfactory. For such structures, we propose using multitemporal images because these can lead to significant improvements and a better roof edge detection. The method used in this study was shared with the Czech national mapping agency and could be used for the creation of new 3D modelling products in the near future.

EFFECT OF ELECTRODE MATERIAL ON CUT QUALITIES OF SHAPE MEMORY ALLOY DURING WEDM: A COMPARATIVE STUDY

2019 ◽  
Vol 27 (04) ◽  
pp. 1950136
Author(s):  
HIMADRI MAJUMDER ◽  
KALIPADA MAITY
Keyword(s):  
Micro Hardness ◽  
Process Variables ◽  
Machining Time ◽  
Five Factors ◽  
Series Of Experiments ◽  
Pulse On Time ◽  
Wedm Process ◽  
Different Levels ◽  
Fesem Micrographs ◽  
Brass Wire

This paper compares some of the vigorous machinability characteristics of SMA-Nitinol during WEDM process using uncoated and zinc coated brass wire electrodes. A series of experiments were regulated based on Taguchi’s L[Formula: see text] orthogonal array with an objective of unveiling the benefits of using coated brass wire electrodes in comparison to uncoated counterparts. Five factors, namely pulse-on time ([Formula: see text]), discharge current ([Formula: see text]), wire tension (WT), wire speed (WS) and flushing pressure (FP), were considered, each at three different levels to scrutinize four responses, viz. surface roughness (Ra), kerf width (KW), machining time (MT) and micro-hardness ([Formula: see text]h). It was perceived that zinc-coated brass wire was more preferable to get favorable responses like Ra, KW and [Formula: see text]h when compared with brass wire counterparts. FESEM micrographs also revealed that micro and large cracks, wide craters, recast layer were more prominent on the WEDMed surface of brass wire compared to zinc-coated brass wire. Use of zinc-coated brass wire electrode significantly improves the machinability of the selected work material within the specified range of process variables.

scholarly journals The Medusa effect reveals levels of mind perception in pictures

2021 ◽  
Vol 118 (32) ◽  
pp. e2106640118
Author(s):  
Paris Will ◽  
Elle Merritt ◽  
Rob Jenkins ◽  
Alan Kingstone
Keyword(s):  
Eye Tracking ◽  
Dictator Game ◽  
Moral Judgement ◽  
Ethical Consideration ◽  
Image Size ◽  
Levels Of Abstraction ◽  
Mind Perception ◽  
Series Of Experiments ◽  
The Mind ◽  
Different Levels

Throughout our species history, humans have created pictures. The resulting picture record reveals an overwhelming preference for depicting things with minds. This preference suggests that pictures capture something of the mind that is significant to us, albeit at reduced potency. Here, we show that abstraction dims the perceived mind, even within the same picture. In a series of experiments, people were perceived as more real, and higher in both Agency (ability to do) and Experience (ability to feel), when they were presented as pictures than when they were presented as pictures of pictures. This pattern persisted across different tasks and even when comparators were matched for identity and image size. Viewers spontaneously discriminated between different levels of abstraction during eye tracking and were less willing to share money with a more abstracted person in a dictator game. Given that mind perception underpins moral judgement, our findings suggest that depicted persons will receive greater or lesser ethical consideration, depending on the level of abstraction.

scholarly journals Oat talgan as a source of antioxidants

2020 ◽  
Vol 15 (1) ◽  
pp. 19-29
Author(s):  
Alena Vladimirovna Sumina ◽  
Vadim Igorevich Polonsky ◽  
Tatyana Mikhailovna Shaldaeva ◽  
Margarita Terentyevna Shulbaeva
Keyword(s):  
Traditional Method ◽  
Reference Sample ◽  
Total Content ◽  
Climatic Conditions ◽  
Bidistilled Water ◽  
Innovative Method ◽  
Series Of Experiments ◽  
Oat Cultivars ◽  
The Republic ◽  
Opposite Tendency

The purpose of the study was to analyze the total content of antioxidants (TAC) in the national Khakass product talgan consisted of oats grain. Talgan was prepared according to traditional (frying, grinding) and innovative (grinding, frying) methods. In this series of experiments, three oat cultivars were used: Argument (chaffy caryopsis), Tubinsky (chaffy caryopsis) and Golets (bare-grained). All samples were grown on the territory of the Beysk state section of the Republic of Khakassia, which was characterized by favorable climatic conditions for growing grain with a high antioxidant content. For TAC determination in grain, 2 solvents were used - bidistilled water and 70% ethanol. The TAC measurement was performed on ‘Tsvet Yauza-01-AA’. Gallic acid was used as a reference sample. In oat talgan, prepared according to the traditional method from chaffy caryopsis samples, the total content of antioxidants had a higher value than that before processing (regardless of the nature of eluting solvent). However, the opposite tendency was observed in the case of bare-grained sample. Higher rates among all samples were recorded when using hot bidistilled water as eluting solvent. The use of innovative method for production of talgan showed that the total content of antioxidants in all samples had higher values in comparison with the traditional method. Using a three-factor analysis, it was found that the TAC values in oat talgan were two-thirds dependent on the method of preparing the product; solvent nature and genotype affected much less.

scholarly journals Asymmetry in genitalia is in sync with lateralized mating behavior but not with the lateralization of other behaviors

2019 ◽  
Vol 66 (1) ◽  
pp. 71-81 ◽  
Author(s):  
Julián Torres-Dowdall ◽  
Sina J Rometsch ◽  
Gastón Aguilera ◽  
Guillermo Goyenola ◽  
Axel Meyer
Keyword(s):  
Natural Populations ◽  
Laboratory Population ◽  
Genital Morphology ◽  
Wild Populations ◽  
Biological Organization ◽  
Individual Level ◽  
Series Of Experiments ◽  
The Right ◽  
Different Levels ◽  
Study Species

Abstract Asymmetries in bilateral organisms attract a lot of curiosity given that they are conspicuous departures from the norm. They allow the investigation of the integration at different levels of biological organization. Here we study whether and how behavioral and asymmetrical anatomical traits co-evolved and work together. We ask if asymmetry is determined locally for each trait or at a whole individual level in a species bearing conspicuous asymmetrical genitalia. Asymmetric genitalia evolved in many species; however, in most cases the direction of asymmetry is fixed. Therefore, it has been rarely determined if there is an association between the direction of asymmetry in genitalia and other traits. In onesided livebearer fish of the genus Jenynsia (Cyprinodontiformes, Anablepidae), the anal fin of males is modified into a gonopodium, an intromittent organ that serves to inseminate females. The gonopodium shows a conspicuous asymmetry, with its tip bending either to the left or the right. By surveying 13 natural populations of Jenynsia lineata, we found that both genital morphs are equally common in wild populations. In a series of experiments in a laboratory population, we discovered asymmetry and lateralization for multiple other traits; yet, the degree of integration varied highly among them. Lateralization in exploratory behavior in response to different stimuli was not associated with genital morphology. Interestingly, the direction of genital asymmetry was positively correlated with sidedness of mating preference and the number of neuromasts in the lateral line. This suggests integration of functionally linked asymmetric traits; however, there is no evidence that asymmetry is determined at the whole individual level in our study species.

scholarly journals Experimental Investigation of the Implications of Model Granularity for Design Process Simulation

2019 ◽  
Vol 141 (7) ◽  
Author(s):  
Jakob F. Maier ◽  
Claudia Eckert ◽  
P. John Clarkson
Keyword(s):  
Diesel Engine ◽  
Design Process ◽  
Process Simulation ◽  
Process Model ◽  
Levels Of Detail ◽  
Building Models ◽  
Design Structure ◽  
Design Changes ◽  
Process Behavior ◽  
Different Levels

Determining a suitable level of description, or granularity, for a product or process model is not straightforward, especially since granularity can manifest in multiple ways, but it is important to capture important elements in the model without building models that are too large to understand. This article investigates the implications of model granularity choices by simulating the design process of a diesel engine on different levels of detail, comparing the results and exploring ways to account for the differences. It uses two Design Structure Matrix (DSM) models for change prediction in a diesel engine at different levels of granularity to run simulations of the design process. Changes are a major source of rework and lead to frequent rescheduling of design tasks. The incremental nature of product development as well as design changes and their propagation complicate design process planning further. Process simulation may provide support in such contexts when it is based on an appropriate description of the product. The article shows that while coarse models can give an indication of likely process behavior, they miss potentially significant iteration loops.

Application of SMA Wire for an Active Steerable Cannula

2013 ◽  
Author(s):  
Bardia Konh ◽  
Mohammad Honarvar ◽  
Parsaoran Hutapea
Keyword(s):  
Solution Procedure ◽  
Design Parameters ◽  
Fe Model ◽  
Stress Strain ◽  
Thermomechanical Characteristics ◽  
Nitinol Wire ◽  
Series Of Experiments ◽  
The One ◽  
Different Levels ◽  
Steerable Cannula

In this article we present the feasibility of using the shape memory alloy (SMA) wires, namely Nitinol, as an actuator for a steerable surgical cannula. A 3D finite element (FE) model of the actuated steerable cannula was then developed in ANSYS to show deflection of the surgical cannula under the actuation force. The behavior of SMAs was simulated by defining the isothermal stress-strain curves using the multi-elasticity capability of ANSYS. The transformation temperatures of the Nitinol wire at different levels of stress were gathered to form the transformation diagram. Using the one-dimensional Brinson model, the isothermal stress-strain response of the wire was obtained. The thermomechanical characteristics of SMAs were also studied completely by a series of experiments performed on the wires. Birth and death method was used in the solution procedure to have the prestrain condition on Nitinol wire prior to the actuation step. A prototype of the actuated steerable cannula was also developed to validate the numerical simulation. Finally a study was done on design parameters affecting the deflection such as Young’s modulus of cannula, SMA diameter and its offset from the neutral axis of the cannula which can be useful in design optimization.

Evaluvation of artificially dried grass as a source of energy for sheep:II. The energy value of cocksfoot, timothy and two strains of rye-grass at varying stages of maturity

1964 ◽  
Vol 62 (3) ◽  
pp. 399-416 ◽  
Author(s):  
D. G. Armstrong
Keyword(s):  
The Other ◽  
Energy Value ◽  
The Third ◽  
Stages Of Growth ◽  
Rye Grass ◽  
Series Of Experiments ◽  
Different Levels

1. Four cuts of rye.grass S 23, three cuts each of cocksfoot S 37 and timothy S 48 and two cuts of rye-grass S 24 taken at different stages of growth and artificially (heat) dried were fed to mature sheep in a series of experiments designed to measure their value as sources of energy. The four cuts of rye-grass S 23 were each given to three sheep–two of the animals receiving it at five different levels of intake and the third at two levels. The other grasses were each given to four sheep at two levels of intake. The fasting heat productions of the sheep were measured at the beginning and end of the grass feeding periods. Altogether 152 experiments were made.

Damping Effect of a Passing Vehicle for Indirectly Measuring Bridge Frequencies by EMD Technique

2018 ◽  
Vol 18 (01) ◽  
pp. 1850008 ◽  
Author(s):  
Judy P. Yang ◽  
Wei-Chun Lee
Keyword(s):  
Surface Roughness ◽  
Traditional Method ◽  
Factors Affecting ◽  
Damping Effect ◽  
Measuring Bridge ◽  
Mode Decomposition ◽  
Numerical Experimentation ◽  
Key Factor ◽  
Road Surface Roughness ◽  
Different Levels

The indirect approach for measuring bridge frequencies from a passing vehicle has become an attractive method recently because it provides mobility, reliability, and safety for setting up sensors in comparison with the traditional method for measurement. In the vehicle–bridge interaction system, it is realized that the bridge frequencies can be identified from the spectral analysis of the passing vehicle. However, there exist many factors affecting the identified results of bridge frequencies, and one key factor is the vehicle damping. This study investigates the effect of vehicle damping on the identification of the first bridge frequency for three different levels of road surface roughness by the empirical mode decomposition (EMD) technique. The numerical experimentation shows the following properties that can be utilized in a field measurement: (1) higher vehicle damping tends to suppress the vehicle frequency, and (2) the use of vehicle damping helps to suppress the effect of rough surface roughness and make the first bridge frequency visible.

scholarly journals Elastic follow-up and relaxation of residual stresses

2010 ◽  
Vol 224 (4) ◽  
pp. 777-787 ◽  
Author(s):  
D J Smith ◽  
J McFadden ◽  
S Hadidimoud ◽  
A J Smith ◽  
A J Stormonth-Darling ◽  
...  
Keyword(s):  
Residual Stress ◽  
Residual Stresses ◽  
Experimental Results ◽  
Test Rig ◽  
Reliable Measure ◽  
Initial Residual Stress ◽  
Series Of Experiments ◽  
Different Levels ◽  
Simple Models

A series of experiments were undertaken using a multiple bar assembly to measure elastic follow-up and relaxation of an initial residual stress. A test rig was designed to permit different levels of elastic follow-up to occur. The general features of the experimental results confirmed predictions provided by simple models. The most reliable measure of elastic follow-up was obtained by measuring the relaxation of the initial residual stress. The rate of relaxation of the residual stress is found to be proportional to the elastic follow-up factor.

Sign in / Sign up

Export Citation Format

Share Document