scholarly journals METHODOLOGY FOR DETERMINING HELMERT'S CONSISTENT PARAMETERS FOR LOCAL TERRITORIES

2021 ◽  
Vol 26 (5) ◽  
pp. 63-74
Author(s):  
Nikolay K. Shendrik ◽  
Keyword(s):  
Coordinate System ◽  
Local Area ◽  
Methodological Error ◽  
Reference Coordinate System ◽  
Terrestrial System ◽  
Novosibirsk Region ◽  
The Common ◽  
Coordi Nates

A method for determining the Helmert matching parameters for converting the coordinates of points from the common terrestrial to the reference coordinate system has developed. The tech-nique is based on the maximum alignment of the surfaces of the common terrestrial and reference el-lipsoids within a certain local territory and does not imply knowledge of the heights of the quasigeoid. The radius of the local area is limited by a given methodological error in the transformation of coordi-nates from general terrestrial system to Gauss-Kruger projection. For a methodical error of ±2–3 cm, the radius of the local area is about 200 km. Two options for determining the Helmert matching parameters for the fourth three-degree zone of the MSC of the Novosibirsk region are given: according to the reconstructed coordinates and heights of the SDGN, and according to the catalog coordinates and heights of the SGN points located in the same territory.

2.2. Working Group 2: Conceptual Definitions of Reference Coordinate Systems for Earth Dynamics

1975 ◽  
Vol 26 ◽  
pp. 21-26
Keyword(s):  
Coordinate System ◽  
Working Group ◽  
General Character ◽  
Coordinate Systems ◽  
Reference Coordinate System ◽  
Group 2 ◽  
Definition Of ◽  
Earth Dynamics

An ideal definition of a reference coordinate system should meet the following general requirements:1. It should be as conceptually simple as possible, so its philosophy is well understood by the users.2. It should imply as few physical assumptions as possible. Wherever they are necessary, such assumptions should be of a very general character and, in particular, they should not be dependent upon astronomical and geophysical detailed theories.3. It should suggest a materialization that is dynamically stable and is accessible to observations with the required accuracy.

Technique for relation global reference system and local realization of global reference system by continuously operated reference stations

2020 ◽  
Vol 962 (8) ◽  
pp. 24-37
Author(s):  
V.E. Tereshchenko
Keyword(s):  
Coordinate System ◽  
Russian Federation ◽  
Reference System ◽  
Main Part ◽  
Precise Point Positioning ◽  
Global Coordinate System ◽  
Coordinate Systems ◽  
Novosibirsk Region ◽  
The Russian Federation

The article suggests a technique for relation global kinematic reference system and local static realization of global reference system by regional continuously operated reference stations (CORS) network. On the example of regional CORS network located in the Novosibirsk Region (CORS NSO) the relation parameters of the global reference system WGS-84 and its local static realization by CORS NSO network at the epoch of fixing stations coordinates in catalog are calculated. With the realization of this technique, the main parameters to be determined are the speed of displacement one system center relativly to another and the speeds of rotation the coordinate axes of one system relatively to another, since the time evolution of most stations in the Russian Federation is not currently provided. The article shows the scale factor for relation determination of coordinate systems is not always necessary to consider. The technique described in the article also allows detecting the errors in determining the coordinates of CORS network in global coordinate system and compensate for them. A systematic error of determining and fixing the CORS NSO coordinates in global coordinate system was detected. It is noted that the main part of the error falls on the altitude component and reaches 12 cm. The proposed technique creates conditions for practical use of the advanced method Precise Point Positioning (PPP) in some regions of the Russian Federation. Also the technique will ensure consistent PPP method results with the results of the most commonly used in the Russian Federation other post-processing methods of high-precision positioning.

scholarly journals LevioSAM: Fast lift-over of alternate reference alignments

2021 ◽  
Author(s):  
Taher Mun ◽  
Nae-Chyun Chen ◽  
Ben Langmead
Keyword(s):  
Population Genetics ◽  
Coordinate System ◽  
Data Structures ◽  
Succinct Data Structures ◽  
Reference Coordinate System ◽  
Link Type ◽  
A Chain ◽  
Time Required ◽  
Effective Use

AbstractMotivationAs more population genetics datasets and population-specific references become available, the task of translating (“lifting”) read alignments from one reference coordinate system to another is becoming more common. Existing tools generally require a chain file, whereas VCF files are the more common way to represent variation. Existing tools also do not make effective use of threads, creating a post-alignment bottleneck.ResultsLevioSAM is a tool for lifting SAM/BAM alignments from one reference to another using a VCF file containing population variants. LevioSAM uses succinct data structures and scales efficiently to many threads. When run downstream of a read aligner, levioSAM completes in less than 13% the time required by an aligner when both are run with 16 threads.Availabilityhttps://github.com/alshai/[email protected], [email protected]

Reference coordinate system in design of shoe lasts

2009 ◽  
Vol 1 (sup1) ◽  
pp. 8-10
Author(s):  
Kirill Zamarashkin ◽  
Nikolai Zamarashkin
Keyword(s):  
Coordinate System ◽  
Reference Coordinate System

scholarly journals Research on Visualization and Error Compensation of Demolition Robot Attachment Changing

Sensors ◽  
2020 ◽  
Vol 20 (8) ◽  
pp. 2428 ◽  
Author(s):  
Qian Deng ◽  
Shuliang Zou ◽  
Hongbin Chen ◽  
Weixiong Duan
Keyword(s):  
Coordinate System ◽  
Coordinate Transformation ◽  
Error Compensation ◽  
Compensation Method ◽  
Positioning Error ◽  
Nuclear Facility ◽  
Reference Coordinate System ◽  
Accuracy Requirement ◽  
Docking Accuracy ◽  
Changing Process

Attachment changing in demolition robots has a high docking accuracy requirement, so it is hard for operators to control this process remotely through the perspective of a camera. To solve this problem, this study investigated positioning error and proposed a method of error compensation to achieve a highly precise attachment changing process. This study established a link parameter model for the demolition robot, measured the error in the attachment changing, introduced a reference coordinate system to solve the coordinate transformation from the dock spot of the robot’s quick-hitch equipment to the dock spot of the attachment, and realized error compensation. Through calculation and experimentation, it was shown that the error compensation method proposed in this study reduced the level of error in attachment changing from the centimeter to millimeter scale, thereby meeting the accuracy requirements for attachment changing. This method can be applied to the remote-controlled attachment changing process of demolition robots, which provides the basis for the subsequent automatic changing of attachments. This has the potential to be applied in nuclear facility decommissioning and dismantling, as well as other radioactive environments.

Wi-Fi Technology

2008 ◽  
pp. 711-716
Author(s):  
Antonios Alexiou ◽  
Dimitrios Antonellis ◽  
Christos Bouras
Keyword(s):  
Wireless Local Area Network ◽  
Local Area Network ◽  
Local Area ◽  
Area Network ◽  
Physical Constraints ◽  
Wired Networks ◽  
Notebook Computers ◽  
Portable Computing ◽  
The Common ◽  
Multicast Services

Wi-Fi, short for “wireless fidelity,” is a term for certain types of wireless local area network (WLAN) that use specifications in the 802.11 family. In general, the wireless technologies are used for the replacement or the expansion of the common wired networks. They possess all the functionality of wired LANs but without the physical constraints of the wire itself. The wireless nature inherently allows easy implementation of broadcast/multicast services. When used with portable computing devices (e.g., notebook computers), wireless LANs are also known as cordless LANs because this term emphasizes the elimination of both power cord and network cable (Tanenbaum, 2003).

A New Three-Dimensional Moving Timoshenko Beam Element for Moving Load Problem Analysis

2020 ◽  
Vol 142 (3) ◽  
Author(s):  
Yan Xu ◽  
Weidong Zhu ◽  
Wei Fan ◽  
Caijing Yang ◽  
Weihua Zhang
Keyword(s):  
Dynamic Analysis ◽  
Coordinate System ◽  
Timoshenko Beam ◽  
Moving Load ◽  
Three Dimensional ◽  
Beam Element ◽  
Superposition Method ◽  
Reference Coordinate System ◽  
Current Formulation ◽  
Timoshenko Beam Element

Abstract A new three-dimensional moving Timoshenko beam element is developed for dynamic analysis of a moving load problem with a very long beam structure. The beam has small deformations and rotations, and bending, shear, and torsional deformations of the beam are considered. Since the dynamic responses of the beam are concentrated on a small region around the moving load and most of the long beam is at rest, owing to the damping effect, the beam is truncated with a finite length. A control volume that is attached to the moving load is introduced, which encloses the truncated beam, and a reference coordinate system is established on the left end of the truncated beam. The arbitrary Lagrangian–Euler method is used to describe the relationship of the position of a particle on the beam between the reference coordinate system and the global coordinate system. The truncated beam is spatially discretized using the current beam elements. Governing equations of a moving element are derived using Lagrange’s equations. While the whole beam needs to be discretized in the finite element method or modeled in the modal superposition method (MSM), only the truncated beam is discretized in the current formulation, which greatly reduces degrees-of-freedom and increases the efficiency. Furthermore, the efficiency of the present beam element is independent of the moving load speed, and the critical or supercritical speed range of the moving load can be analyzed through the present method. After the validation of the current formulation, a dynamic analysis of three-dimensional train–track interaction with a non-ballasted track is conducted. Results are in excellent agreement with those from the commercial software simpack where the MSM is used, and the calculation time of the current formulation is one-third of that of simpack. The current beam element is accurate and more efficient than the MSM for moving load problems of long three-dimensional beams. The derivation of the current beam element is straightforward, and the beam element can be easily extended for various other moving load problems.

Computation of Common Normal Between a Wheelset and Straight Rail at Singular Position

2014 ◽  
Author(s):  
Behrooz Fallahi ◽  
Arjun Kumar Perla ◽  
Andrew Behnke
Keyword(s):  
Coordinate System ◽  
Nonlinear Equations ◽  
Newton Method ◽  
Hybrid Procedure ◽  
Bisection Method ◽  
Parametric Equation ◽  
Wheel Surface ◽  
Special Position ◽  
The Common ◽  
Position And Orientation

Computation of common normal between a pair of wheel and rail surface is an important sub problem in railroad simulations. In this study, it is shown that there are special position and orientation of every wheelset that makes the governing equation for computation of the common normal degenerate. This condition leads to divergence of the Newton’s iterate. To develop a procedure that can successfully compute the common normal between a straight rail and a wheelset, first parametric equation for the rail and wheel surface in track coordinate system is developed. Then four nonlinear equations whose solution is location of common normal are constructed. Three of the equations are used to eliminate three unknown in fourth equation. The resulting equation has only one unknown. A hybrid procedure based on Newton method and bisection method is used to solve the roots of the last equation. The utility of this approach is demonstrated by reporting the common normal for a pair of wheel and rail surface at singular position.

scholarly journals Geometric characteristics of the deformation state of the shells with orthogonal coordinate system of the middle surfaces

2020 ◽  
Vol 16 (1) ◽  
pp. 38-44
Author(s):  
Vyacheslav N. Ivanov ◽  
Alisa A. Shmeleva
Keyword(s):  
Differential Geometry ◽  
Coordinate System ◽  
Thin Shell ◽  
Tensor Analysis ◽  
Vector Analysis ◽  
Thin Shells ◽  
Orthogonal Coordinate System ◽  
Deformation State ◽  
The Common ◽  
To Receive

The aim of this work is to receive the geometrical equations of strains of shells at the common orthogonal not conjugated coordinate system. At the most articles, textbooks and monographs on the theory and analysis of the thin shell there are considered the shells the coordinate system of which is given at the lines of main curvatures. Derivation of the geometric equations of the deformed state of the thin shells in the lines of main curvatures is given, specifically, at monographs of the theory of the thin shells of V.V. Novozhilov, K.F. Chernih, A.P. Filin and other Russian and foreign scientists. The standard methods of mathematic analyses, vector analysis and differential geometry are used to receive them. The method of tensor analysis is used for receiving the common equations of deformation of non orthogonal coordinate system of the middle shell surface of thin shell. The equations of deformation of the shells in common orthogonal coordinate system (not in the lines of main curvatures) are received on the base of this equation. Derivation of the geometric equations of deformations of thin shells in orthogonal not conjugated coordinate system on the base of differential geometry and vector analysis (without using of tensor analysis) is given at the article. This access may be used at textbooks as far as at most technical institutes the base of tensor analysis is not given.

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