scholarly journals A Global Continuous Multi-Scale Terrain Contour Simplification Method Based on the Level Set

2021 ◽  
Vol 11 (9) ◽  
pp. 3855
Author(s):  
Haoyue Qian ◽  
Lin Yang ◽  
Zejun Zuo ◽  
Run Wang ◽  
Wenjie Zhen ◽  
...  
Keyword(s):  
Level Set ◽  
Spatial Representation ◽  
Surface Model ◽  
Multi Scale ◽  
Levels Of Detail ◽  
Contour Lines ◽  
Real Contour ◽  
Potential Applications ◽  
Different Levels ◽  
Mapping Systems

Multi-scale spatial representation has been widely used in geographic information and online mapping systems. Terrain contour, which provides a reference for understanding and monitoring the Earth’s surface, is an important data category. For the multi-scale representation of contour lines, simplification is a fundamental step in providing different levels of detail for linear features. However, achieving a global continuous multi-scale simplification of contours remains a challenge. Therefore, based on the concept of level set, a novel contour simplification method labeled the continuous changing surface model (CCSM) was proposed in this paper. The CCSM was built by using a non-uniform rational B-spline constrained with characteristics and was then intersected with a set of horizontal planes with progressive height values. The generated intersection lines are considered continuous multi-scale simplified contours. Experiments were conducted on a 1:50,000 real contour dataset to verify the effectiveness of CCSM. Results showed that the changes in the shape of the simplified contours generated by CCSM are more natural and progressive than those generated by two other significant simplification methods. CCSM can also effectively balance local and global structures and has potential applications in obtaining a continuous multi-scale representation of terrain contours.

An Interactive Graph Partition Method Through Combination of Multi-scale Analysis and Level Set

2013 ◽  
Vol 34 (9) ◽  
pp. 2078-2084 ◽  
Author(s):  
Yun-fei Wang ◽  
Du-yan Bi ◽  
De-qin Shi ◽  
Tian-jun Huang ◽  
Di Liu
Keyword(s):  
Level Set ◽  
Graph Partition ◽  
Scale Analysis ◽  
Multi Scale ◽  
Partition Method ◽  
Multi Scale Analysis

Development of a Simulation-Based Process Chain – Strategy for Different Levels of Detail for the Preprocessing Definitions

2011 ◽  
Vol 21 (3-4) ◽  
pp. 135-140 ◽  
Author(s):  
Toni A. Krol ◽  
Sebastian Westhäuser ◽  
M. F. Zäh ◽  
Johannes Schilp ◽  
G. Groth
Keyword(s):  
Process Chain ◽  
Levels Of Detail ◽  
Simulation Based ◽  
Different Levels

Cloning and functional expression of α-galactosidase cDNA from Penicillium janczewskii zaleski

Biologia ◽  
2011 ◽  
Vol 66 (2) ◽  
Author(s):  
Bo Zhang ◽  
Yiqun Chen ◽  
Zhimin Li ◽  
Wenqing Lu ◽  
Yunhe Cao
Keyword(s):  
Ethylenediaminetetraacetic Acid ◽  
Functional Expression ◽  
Recombinant Enzyme ◽  
Methanol Induction ◽  
Potential Applications ◽  
Prospective Application ◽  
Polymerase Chain ◽  
Penicillium Janczewskii ◽  
Rapid Amplification ◽  
Different Levels

AbstractIn recent years, α-galactosidase has been attracting more and more attention because of its potential applications in many aspects. Using reverse transcription-polymerase chain reaction and rapid amplification of cDNA ends, a full-length cDNA sequence composed of 2,439 bp was cloned from Penicillium janczewskii zaleski and was subcloned into pPICZαA and transformed into Pichia pastoris strain X-33. In a 10-L fermentor, the recombinant yeast expressed α-galactosidase with a yield of 254 U/mL by methanol induction for 120 h. The recombinant enzyme showed the optimal activity at 40°C and pH 5.2. The K m values of the recombinant enzyme using p-nitrophenyl-α-D-galactopyranoside (pNPG), melibiose, raffinose and stachyose as substrates were 1, 16, 17.8 and 5.3 mM, respectively. V max values were 227.3, 116.7, 104.8, and 80.6 μM/min using pNPG, melibiose, raffinose and stachyose as substrates, respectively. The α-galactosidase exhibited no sensitivity to various metal ions and ethylenediaminetetraacetic acid, and hydrolyzed melibiose, raffinose and stachyose with different levels of galactose release. The biochemical characteristics of the α-galactosidase suggest that the enzyme may have a prospective application in feed industry as an additive.

scholarly journals The Development of Multi-scale Data Management for CityGML-based 3D Buildings

2021 ◽  
Vol 16 (1) ◽  
pp. 71-94
Author(s):  
Hairi Karim ◽  
Alias Abdul Rahman ◽  
Suhaibah Azri ◽  
Zurairah Halim
Keyword(s):  
City Development ◽  
Multi Scale ◽  
Levels Of Detail ◽  
Current Implementation ◽  
Single Scale ◽  
Spatial Management ◽  
Scale Models ◽  
Efficient Information ◽  
Control And Management ◽  
Multi Scales

The CityGML model is now the norm for smart city or digital twin city development for better planning, management, risk-related modelling and other applications. CityGML comes with five levels of detail (LoD), mainly constructed from point cloud measurements and images of several systems, resulting in a variety of accuracies and detailed models. The LoDs, also known as pre-defined multi-scale models, require large storage-memory-graphic consumption compared to single scale models. Furthermore, these multi-scales have redundancy in geometries, attributes, are costly in terms of time and workload in updating tasks, and are difficult to view in a single viewer. It is essential for data owners to engage with a suitable multi-scale spatial management solution in minimizes the drawbacks of the current implementation. The proper construction, control and management of multi-scale models are needed to encourage and expedite data sharing among data owners, agencies, stakeholders and public users for efficient information retrieval and analyses. This paper discusses the construction of the CityGML model with different LoDs using several datasets. A scale unique ID is introduced to connect all respective LoDs for cross-LoD information queries within a single viewer. The paper also highlights the benefits of intermediate outputs and limitations of the proposed solution, as well as suggestions for the future.

scholarly journals AUTOMATIC ROOFTOP EXTRACTION IN STEREO IMAGERY USING DISTANCE AND BUILDING SHAPE REGULARIZED LEVEL SET EVOLUTION

2017 ◽  
Vol XLII-1/W1 ◽  
pp. 393-397 ◽  
Author(s):  
J. Tian ◽  
T. Krauß ◽  
P. d’Angelo
Keyword(s):  
Level Set ◽  
Active Contour Model ◽  
Digital Terrain Model ◽  
Surface Model ◽  
Building Shape ◽  
Fitting Procedure ◽  
Level Set Function ◽  
Stereo Imagery ◽  
3D Information ◽  
High Level

Automatic rooftop extraction is one of the most challenging problems in remote sensing image analysis. Classical 2D image processing techniques are expensive due to the high amount of features required to locate buildings. This problem can be avoided when 3D information is available. In this paper, we show how to fuse the spectral and height information of stereo imagery to achieve an efficient and robust rooftop extraction. In the first step, the digital terrain model (DTM) and in turn the normalized digital surface model (nDSM) is generated by using a newly step-edge approach. In the second step, the initial building locations and rooftop boundaries are derived by removing the low-level pixels and high-level pixels with higher probability to be trees and shadows. This boundary is then served as the initial level set function, which is further refined to fit the best possible boundaries through distance regularized level-set curve evolution. During the fitting procedure, the edge-based active contour model is adopted and implemented by using the edges indicators extracted from panchromatic image. The performance of the proposed approach is tested by using the WorldView-2 satellite data captured over Munich.

Geographic Disparities in Health

2020 ◽  
pp. 265-280
Author(s):  
Tomoki Nakaya ◽  
Tomoya Hanibuchi
Keyword(s):  
Social Inequalities ◽  
Residential Areas ◽  
Metropolitan Regions ◽  
Multi Scale ◽  
The World ◽  
Socioeconomic Segregation ◽  
Supportive Environments ◽  
Post War ◽  
Neighbourhood Scale ◽  
Different Levels

This chapter highlights the geographical aspects of health disparities in Japan at different levels, from the 47 prefectures nationally to the neighbourhood level. In the post-war period, Japan has successfully attained the longest life expectancy in the world. At the same time, it has substantially reduced geographical disparities among the prefectures. This indicates that reducing such disparities in living standards may also be related to improving the health of a country’s entire population. However, disparities of health have appeared among populations living in socially segmented areas in large neighbourhoods of metropolitan regions. Such neighbourhood-scale disparities in health are associated with a number of environmental characteristics of Japanese neighbourhoods reflecting socioeconomic segregation and development histories of residential areas. In the era of a super-aging society that contains the threat of re-widening social inequalities, Japan faces challenges to build health-supportive environments for tackling multi-scale disparities.

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.

Architecture for Symbolic Object Warehouse

2009 ◽  
pp. 648-657
Author(s):  
Sandra Elizabeth González Císaro ◽  
Héctor Oscar Nigro
Keyword(s):  
Decision Making ◽  
Data Warehouse ◽  
Complex Data ◽  
Data Complexity ◽  
Intrinsic Structure ◽  
Levels Of Detail ◽  
Decision Making Processes ◽  
Design Systems ◽  
Central Database ◽  
Different Levels

Much information stored in current databases is not always present at necessary different levels of detail or granularity for Decision-Making Processes (DMP). Some organizations have implemented the use of central database - Data Warehouse (DW) - where information performs analysis tasks. This fact depends on the Information Systems (IS) maturity, the type of informational requirements or necessities the organizational structure and business own characteristic. A further important point is the intrinsic structure of complex data; nowadays it is very common to work with complex data, due to syntactic or semantic aspects and the processing type (Darmont et al., 2006). Therefore, we must design systems, which can to maintain data complexity to improve the DMP.

scholarly journals Adversarial Training for Community Question Answer Selection Based on Multi-Scale Matching

2019 ◽  
Vol 33 ◽  
pp. 395-402
Author(s):  
Xiao Yang ◽  
Madian Khabsa ◽  
Miaosen Wang ◽  
Wei Wang ◽  
Ahmed Hassan Awadallah ◽  
...  
Keyword(s):  
Question Answering ◽  
State Of The Art ◽  
Classification Problem ◽  
Classification Model ◽  
Training Set ◽  
Community Based ◽  
Multi Scale ◽  
Adversarial Training ◽  
Source Of Information ◽  
Different Levels

Community-based question answering (CQA) websites represent an important source of information. As a result, the problem of matching the most valuable answers to their corresponding questions has become an increasingly popular research topic. We frame this task as a binary (relevant/irrelevant) classification problem, and present an adversarial training framework to alleviate label imbalance issue. We employ a generative model to iteratively sample a subset of challenging negative samples to fool our classification model. Both models are alternatively optimized using REINFORCE algorithm. The proposed method is completely different from previous ones, where negative samples in training set are directly used or uniformly down-sampled. Further, we propose using Multi-scale Matching which explicitly inspects the correlation between words and ngrams of different levels of granularity. We evaluate the proposed method on SemEval 2016 and SemEval 2017 datasets and achieves state-of-the-art or similar performance.

Kinetics Study of the Acidic Catalyzed Polymerization of Tetraethoxysilane by 29Si NMR.

1988 ◽  
Vol 121 ◽  
Author(s):  
Jean-Claude Pouxviel ◽  
J. P. Boilot
Keyword(s):  
Significant Contribution ◽  
Hydrolysis Rate ◽  
Hydroxyl Groups ◽  
29Si Nmr ◽  
Condensation Reactions ◽  
Levels Of Detail ◽  
Degree Of Condensation ◽  
By Products ◽  
Different Levels

ABSTRACTTEOS has been hydrolysed under acidic condition with stoichiome-tric or excess amount of water. Evolution of the silicon species is followed by 29Si NMR. The data are analyzed at different levels of detail; first, analysis of the by products of polymerization reactions, second determination of the extents and overall rate constants of hydrolysis and condensation reactions and finally kinetics simulations of the evolution taking into account all the present silicon species. We have shown that the hydrolysis rate increases with the number of hydroxyl groups, and the reesterification reactions have a significant contribution. We also found that condensation reactions preferentially occur with loss of water between the more hydrolyzed monomers; their rates rapidly decrease with the degree of condensation. We compare the two compositions as a function of their water content and pH.

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