scholarly journals QUANTIFICATION OF SHORELINE RHYTHMICITY

1984 ◽  
Vol 1 (19) ◽  
pp. 145
Author(s):  
Holly C. Garrow
Keyword(s):  
Multivariate Analysis ◽  
Survey Data ◽  
Three Dimensional ◽  
Eof Analysis ◽  
Shoreline Position ◽  
Dune Erosion ◽  
Beach Morphology ◽  
Topographic Data ◽  
Alternative Approach ◽  
Beach Survey

The study of beach morphology, for example, its changes with wave and tide conditions, is facilitated by the development of simple numerical values which characterize the morphology. Multivariate (EOF) analysis of topographic contour data is a means for determining important morphologic components which vary independently. If these components correspond to familiar shoreline features the researcher considers important, then the development of each component can be quantified by its significance, or weighting, in each sample. Alternatively, the components may be complicated and not useful in quantifying beach morphology. A study of these morphologic components, however, can provide insights into the dynamics of the beach system. If multivariate analysis produces complicated components, an alternative approach, of subjectively identifying shoreline characteristics of interest, can be taken. The characteristics may be the same as those frequently used in past studies, such as beach slope or sand volume. It is likely, though, that EOF analysis of topographic data will suggest more sophisticated characteristics which should be used. Some of these, for example, mean shoreline position or amplitude of a rhythmic shoreline, may be easily quantified, whereas, others such as longshore position of rhythmic features or cusp width relative to embayment width, may be more difficult to quantify. Both of these analysis approaches were applied to beach survey data obtained over a period of ten months (including the El Nifto winter of 1982/83) on Siletz Spit, Oregon. The shoreline was rhythmic with an 800-850 m wavelength throughout the duration of the study. Rhythmic topography has been associated with significant past beach and dune erosion at this site. Hence, it is of interest to describe the beach morphology quantitatively, and relate three dimensional beach changes to wave and tide conditions.

The Division of Housework Among “Remarried” Couples

1997 ◽  
Vol 18 (2) ◽  
pp. 205-223 ◽  
Author(s):  
ORIEL SULLIVAN
Keyword(s):  
Multivariate Analysis ◽  
Survey Data ◽  
Focus Of Attention ◽  
Significant Issue ◽  
Representative Survey ◽  
Housework Time ◽  
Cohabiting Couples ◽  
Division Of Housework ◽  
Nationally Representative ◽  
Remarried Couples

There are only a limited number of studies comparing housework among couples and individuals in different marital statuses, and the focus of attention has tended to be on married compared to cohabiting couples. This article focuses on differences between couples where one or more partner is remarried or recohabiting and those where both partners are in their first married or cohabiting relationships, using nationally representative survey data from Britain. It is shown in multivariate analysis that women in their second-plus partnerships contribute less in terms of their proportion of total housework time than women in their first partnerships. However, there is no effect for the man's number of previous partnerships or for current marital/cohabiting status. It is argued that the significant issue is interaction and negotiation with a subsequent partner in the light of experience gained from the breakdown of one or more previous married/cohabiting relationships.

scholarly journals Alternative Approach to Infinity

1974 ◽  
Vol 64 ◽  
pp. 99-99
Author(s):  
Peter G. Bergmann
Keyword(s):  
Large Class ◽  
Riemannian Manifolds ◽  
Quotient Space ◽  
Three Dimensional ◽  
Cauchy Data ◽  
Space Time ◽  
Equivalence Classes ◽  
Null Infinity ◽  
Alternative Approach ◽  
Dimensional Domain

Following Penrose's construction of space-time infinity by means of a conformal construction, in which null-infinity is a three-dimensional domain, whereas time- and space-infinities are points, Geroch has recently endowed space-infinity with a somewhat richer structure. An approach that might work with a large class of pseudo-Riemannian manifolds is to induce a topology on the set of all geodesics (whether complete or incomplete) by subjecting their Cauchy data to (small) displacements in space-time and Lorentz rotations, and to group the geodesics all of whose neighborhoods intersect into equivalence classes. The quotient space of geodesics over equivalence classes is to represent infinity. In the case of Minkowski, null-infinity has the usual structure, but I0, I+, and I- each become three-dimensional as well.

scholarly journals Dynamic modeling of tunnel survey spatiotemporal data

2014 ◽  
Vol 20 (2) ◽  
pp. 354-375
Author(s):  
Xiaolong Li ◽  
Jiansi Yang ◽  
Bingxuan Guo ◽  
Hua Liu ◽  
Jun Hua
Keyword(s):  
Survey Data ◽  
Cross Section ◽  
Cross Sections ◽  
3D Modeling ◽  
3D Model ◽  
Three Dimensional ◽  
Spatiotemporal Data ◽  
Excavation Process ◽  
Special Cases ◽  
Time Stamps

Currently, for tunnels, the design centerline and design cross-section with time stamps are used for dynamic three-dimensional (3D) modeling. However, this approach cannot correctly reflect some qualities of tunneling or some special cases, such as landslips. Therefore, a dynamic 3D model of a tunnel based on spatiotemporal data from survey cross-sections is proposed in this paper. This model can not only playback the excavation process but also reflect qualities of a project typically missed. In this paper, a new conceptual model for dynamic 3D modeling of tunneling survey data is introduced. Some specific solutions are proposed using key corresponding technologies for coordinate transformation of cross-sections from linear engineering coordinates to global projection coordinates, data structure of files and database, and dynamic 3D modeling. A 3D tunnel TIN model was proposed using the optimized minimum direction angle algorithm. The last section implements the construction of a survey data collection, acquisition, and dynamic simulation system, which verifies the feasibility and practicality of this modeling method.

scholarly journals Integration, Processing and Dissemination of LiDAR Data in a 3D Web-GIS

2019 ◽  
Vol 8 (3) ◽  
pp. 144 ◽  
Author(s):  
Marek Kulawiak ◽  
Marcin Kulawiak ◽  
Zbigniew Lubniewski
Keyword(s):  
Survey Data ◽  
Three Dimensional ◽  
Point Clouds ◽  
3D Models ◽  
Web Gis ◽  
Data Organization ◽  
3D Model Reconstruction ◽  
Open Standards ◽  
3D Lidar ◽  
The City

The rapid increase in applications of Light Detection and Ranging (LiDAR) scanners, followed by the development of various methods that are dedicated for survey data processing, visualization, and dissemination constituted the need of new open standards for storage and online distribution of collected three-dimensional data. However, over a decade of research in the area has resulted in a number of incompatible solutions that offer their own ways of disseminating results of LiDAR surveys (be it point clouds or reconstructed three-dimensional (3D) models) over the web. The article presents a unified system for remote processing, storage, visualization, and dissemination of 3D LiDAR survey data, including 3D model reconstruction. It is built with the use of open source technologies and employs open standards, such as 3D Tiles, LASer (LAS), and Object (OBJ) for data distribution. The system has been deployed for automatic organization, processing, and dissemination of LiDAR surveys that were performed in the city of Gdansk. The performance of the system has been measured using a selection of LiDAR datasets of various sizes. The system has shown to considerably simplify the process of data organization and integration, while also delivering tools for easy discovery, inspection, and acquisition of desired datasets.

scholarly journals Measuring Differential Volume Using the Subtraction Tool for Three-Dimensional Breast Volumetry: A Proof of Concept Study

2020 ◽  
pp. 155335062094556
Author(s):  
Faith Hyun Kyung Jeon ◽  
Michelle Griffin ◽  
Aurora Almadori ◽  
Jajini Varghese ◽  
Stephanie Bogan ◽  
...  
Keyword(s):  
Three Dimensional ◽  
Computer Software ◽  
Patient Positioning ◽  
Volumetric Analysis ◽  
Volumetric Assessment ◽  
Alternative Approach ◽  
Significant Difference ◽  
Actual Volume ◽  
Novel Method ◽  
The Subject

Background. Three-dimensional (3D) photography provides a promising means of breast volumetry. Sources of error using a single-captured surface to calculate breast volume include inaccurate designation of breast boundaries and prediction of the invisible chest wall generated by computer software. An alternative approach is to measure differential volume using subtraction of 2 captured surfaces. Objectives. To explore 3D breast volumetry using the subtraction of superimposed images to calculate differential volume. To assess optimal patient positioning for accurate volumetric assessment. Methods. Known volumes of breast enhancers simulated volumetric changes to the breast (n = 12). 3D photographs were taken (3dMDtorso) with the subject positioned upright at 90° and posteriorly inclined at 30°. Patient position, breathing, distance and camera calibration were standardised. Volumetric analysis was performed using 3dMDvultus software. Results. A statistically significant difference was found between actual volume and measured volumes with subjects positioned at 90° ( P < .05). No statistical difference was found at 30° ( P = .078), but subsequent Bland–Altman analysis showed evidence of proportional bias ( P < .05). There was good correlation between measured and actual volumes in both positions (r = .77 and r = .85, respectively). Univariate analyses showed breast enhancer volumes of 195 mL and 295 mL to incur bias. The coefficient of variation was 5.76% for single observer analysis. Conclusion. Positioning the subject at a 30° posterior incline provides more accurate results from better exposure of the inferior breast. The subtraction tool is a novel method of measuring differential volume. Future studies should explore methodology for application into the clinical setting.

Analysis of powder-snow avalanches using three-dimensional topographic data

1993 ◽  
Vol 18 ◽  
pp. 102-106 ◽  
Author(s):  
Yusuke Fukushima ◽  
Norio Hayakawa
Keyword(s):  
Three Dimensional ◽  
Dynamical Model ◽  
Snow Avalanches ◽  
Topographic Data ◽  
Reasonable Prediction ◽  
Fluid Dynamical Model

A fluid-dynamical model of powder-snow avalanches is developed which takes into account three-dimensional topography and can compute an avalanche’s running course. The model also predicts the variations of height, speed and concentration of snow particles in the avalanche, as well as the level of turbulence. Application of the model to the Maseguchi avalanche, which occurred in 1986 at Niigata, Japan, shows it can provide reasonable prediction of the running course, height and speed of an avalanche.

scholarly journals A Simple Analytical Model for Estimating the Dissolution-Driven Instability in a Porous Medium

Fluids ◽  
2018 ◽  
Vol 3 (3) ◽  
pp. 60
Author(s):  
Layachi Hadji
Keyword(s):  
Stability Problem ◽  
Three Dimensional ◽  
Step Function ◽  
New Approach ◽  
Engineering Mathematics ◽  
Alternative Approach ◽  
Function Base ◽  
The Stability ◽  
Rayleigh Benard ◽  
Profile Approach

This article deals with the stability problem that arises in the modeling of the geological sequestration of carbon dioxide. It provides a more detailed description of the alternative approach to tackling the stability problem put forth by Vo and Hadji (Physics of Fluids, 2017, 29, 127101) and Wanstall and Hadji (Journal of Engineering Mathematics, 2018, 108, 53–71), and it extends two-dimensional analysis to the three-dimensional case. This new approach, which is based on a step-function base profile, is contrasted with the usual time-evolving base state. While both provide only estimates for the instability threshold values, the step-function base profile approach has one great advantage in the sense that the problem at hand can be viewed as a stationary Rayleigh–Bénard problem, the model of which is physically sound and the stability of which is not only well-defined but can be analyzed by a variety of existing analytical methods using only paper and pencil.

Loyalists, cynics and outsiders: who are the critics of the justice system in the UK and the Netherlands?

2011 ◽  
Vol 7 (1) ◽  
pp. 31-46 ◽  
Author(s):  
Marc Hertogh
Keyword(s):  
The Netherlands ◽  
Survey Data ◽  
Comparative Studies ◽  
Justice System ◽  
Demographic Profile ◽  
Alternative Approach ◽  
Administration Of Justice ◽  
The Uk ◽  
Legal Identification

AbstractRecent surveys in the UK and the Netherlands indicate that there is widespread dissatisfaction with the justice system. But who are these ‘critics’ of the justice system? Most previous studies only produced general statistics, while the persons behind the figures remained invisible. By contrast, this article aims to put a face to these numbers and discusses two ways of analysing the profile of the critics. Based on a review of existing survey data, the article first looks at their ‘demographic profile’. Next, the article also considers a second, alternative, approach. Based on their level of legal awareness and legal identification, it distinguishes four different ‘normative profiles’: legalists, loyalists, cynics and outsiders. Moreover, the article shows how these normative profiles may be applied in future comparative studies on legal mobilisation and legal protest. It is concluded that combining both approaches will help us to look beyond common stereotypes and consider the critics of the justice system as real persons with genuine concerns about the administration of justice in their country.

Sign in / Sign up

Export Citation Format

Share Document