scholarly journals Frames of spatial reference in Kilivila

2001 ◽  
Vol 25 (3) ◽  
pp. 521-555 ◽  
Author(s):  
Gunter Senft

Members of the MPI for Psycholinguistics are researching the interrelationship between language, cognition and the conceptualization of space in various languages. Research results show that there are three frames of spatial reference, the absolute, the relative, and the intrinsic frame of reference. This study first presents results of this research in general and then discusses the results for Kilivila. Speakers of this Austronesian language prefer the intrinsic frame of reference for the location of objects with respect to each other in a given spatial configuration. But they prefer an absolute frame of reference system in referring to the spatial orientation of objects in a given spatial configuration. Moreover, the hypothesis is confirmed that languages seem to influence the choice and the kind of conceptual parameters their speakers use to solve non-verbal problems within the domain of space.

Polar Record ◽  
2021 ◽  
Vol 57 ◽  
Author(s):  
Colin Southwell ◽  
David Smith ◽  
Angela Bender ◽  
Louise Emmerson

Abstract We describe a spatial reference system that uniquely identifies 4884 coastal island and continental rock features across East Antarctica. The system comprises a series of maps and a related database, and can be a foundation tool for a wide range of environmental studies.


Author(s):  
O. Hasler ◽  
S. Nebiker

Abstract. Estimating the pose of a mobile robotic platform is a challenging task, especially when the pose needs to be estimated in a global or local reference frame and when the estimation has to be performed while the platform is moving. While the position of a platform can be measured directly via modern tachymetry or with the help of a global positioning service GNSS, the absolute platform orientation is harder to derive. Most often, only the relative orientation is estimated with the help of a sensor mounted on the robotic platform such as an IMU, with one or multiple cameras, with a laser scanner or with a combination of any of those. Then, a sensor fusion of the relative orientation and the absolute position is performed. In this work, an additional approach is presented: first, an image-based relative pose estimation with frames from a panoramic camera using a state-of-the-art visual odometry implementation is performed. Secondly, the position of the platform in a reference system is estimated using motorized tachymetry. Lastly, the absolute orientation is calculated using a visual marker, which is placed in the space, where the robotic platform is moving. The marker can be detected in the camera frame and since the position of this marker is known in the reference system, the absolute pose can be estimated. To improve the absolute pose estimation, a sensor fusion is conducted. Results with a Lego model train as a mobile platform show, that the trajectory of the absolute pose calculated independently with four different markers have a deviation < 0.66 degrees 50% of the time and that the average difference is < 1.17 degrees. The implementation is based on the popular Robotic Operating System ROS.


2021 ◽  
Vol 4 ◽  
pp. 1-8
Author(s):  
Bashkim Idrizi

Abstract. The state Coordinate Reference System (CRS) of the Republic of North Macedonia (RNM) has been established a century ago, by the Military Geographic Institute of the Yugoslavia Kingdom. It is in official usage entire period up to day. In international public EPSG registry of geodetic datums, spatial reference systems, Earth ellipsoids, coordinate transformations and related units of measurement, CRS for RNM is recognizable within 3 EPSG codes 6204, 6316 and 8679.First code EPSG 6204 represents current state CRS for the entire country area, based on current law, however unfortunately this CRS is official by the law but it is not used for developing the official spatial data published in geoportals of Agency for Real Estate Cadastre (AREC) and NSDI geoportal of RNM. The second code EPSG 6316 is defined to be used for 6 countries of former Yugoslavia that covers area between 19.5°E up to 22.5°E longitude, which does not correspond with the practical and official usage of CRS for working with spatial data in RNM and CRS law definition in RNM. Third code EPSG 8679 has never been used in RNM, which covers eastern part of RNM and Serbia beginning from 22.5°E.Beside of problems with EPSG codes, default transformation parameters of EPSG 6316 have low accuracy and can not be used for data overlapping with open layers. Therefore, redefined new EPSG codes for state CRS of RNM are proposed in this paper.


Author(s):  
Marcello Berzeri ◽  
Marcello Campanelli ◽  
A. A. Shabana

Abstract The equivalence of the elastic forces of finite element formulations used in flexible multibody dynamics is the focus of this investigation. Two conceptually different finite element formulations that lead to exact modeling of the rigid body dynamics will be used. These are the floating frame of reference formulation and the absolute nodal coordinate formulation. It is demonstrated in this study that different element coordinate systems, which are used for the convenience of describing the element deformations in the absolute nodal coordinate formulation, lead to similar results as the element size is reduced. The equivalence of the elastic forces in the absolute nodal coordinate and the floating frame of reference formulations is shown. The result of this analysis clearly demonstrates that the instability observed in high speed rotor analytical models due to the neglect of the geometric centrifugal stiffening is not a problem inherent to a particular finite element formulation but only depends on the beam model that is used. Fourier analysis of the solutions obtained in this investigation also sheds new light on the fundamental problem of the choice of the deformable body coordinate system in the floating frame of reference formulation. A new method is presented and used to obtain a simple expression for the elastic forces in the absolute nodal coordinate formulation. This method, which employs a nonlinear elastic strain-displacement relationship, does not result in an unstable solution when the angular velocity is increased.


2011 ◽  
Vol 2 (1) ◽  
pp. 18-35
Author(s):  
Daniel Fitzner

Geoprocessing operations offered via web services provide the means for building complex web-based geospatial applications. Often, certain postconditions such as the spatial reference system, bounding box, schema or quality that hold on the output dataset after the execution of a geoprocessing service are determined and derived from the properties of the inputs passed to the service. Further, geoprocesses often hold preconditions that relate to more than one input, such as the requirement that all inputs must have the same schema. Within current process descriptions for geoprocessing operations, such conditions which we call cross-parameter conditions, can not be explicitly specified. In this paper, the author gives an approach to formalize such cross input-output and cross input parameter conditions in a rule-based language. Further, the author proposes an algorithm for deriving pre- and postconditions for a service composition or workflow out of the pre- and postconditions of the services involved, allowing a more automated handling of workflows in general.


1970 ◽  
Vol 7 ◽  
pp. 103-104
Author(s):  
W. F. van Altena ◽  
B. F. Jones

The establishment of a truly inertial reference system is a problem that has defied solution for many years. However, with the completion of the Lick proper motion survey (Wright 1950) and the USSR program (Deutsch 1954) the situation for the northern hemisphere should be satisfactory.


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