Are kernels the mustard? Data from global positioning system (GPS) collars suggests problems for kernel home-range analyses with least-squares cross-validation

We examined the spatial interactions of nine female White-tailed Deer (Odocoileus virginianus) in two deeryards (winter aggregations) in northeastern Minnesota during February-April 1999. Global positioning system (GPS) collars yielded seven pair-wise comparisons of deer that were located at the same time (≤1 minute apart) and that used overlapping areas. Deer traveled separately and did not associate with one another. Within overlapping areas, comparisons of distances between deer and distances between random locations indicated deer moved without regard to each other. Similarly, comparisons of observed and expected probabilities of deer using areas overlapping those of other deer also evinced that deer moved independently.

Download Full-text

Estimating satellite and receiver differential code bias using a relative Global Positioning System network

Annales Geophysicae ◽

10.5194/angeo-37-1039-2019 ◽

2019 ◽

Vol 37 (6) ◽

pp. 1039-1047 ◽

Cited By ~ 2

Author(s):

Alaa A. Elghazouly ◽

Mohamed I. Doma ◽

Ahmed A. Sedeek

Keyword(s):

Least Squares ◽

Global Positioning System ◽

Gps Data ◽

Electron Content ◽

Positioning System ◽

Total Electron ◽

Gps Network ◽

Global Positioning ◽

The Mean ◽

Mean Differences

Abstract. Precise total electron content (TEC) is required to produce accurate spatial and temporal resolution of global ionosphere maps (GIMs). Receivers and satellite differential code biases (DCBs) are one of the main error sources in estimating precise TEC from Global Positioning System (GPS) data. Recently, researchers have been interested in developing models and algorithms to compute DCBs of receivers and satellites close to those computed from the Ionosphere Associated Analysis Centers (IAACs). Here we introduce a MATLAB code called Multi Station DCB Estimation (MSDCBE) to calculate satellite and receiver DCBs from GPS data. MSDCBE based on a spherical harmonic function and a geometry-free combination of GPS carrier-phase, pseudo-range code observations, and weighted least squares was applied to solve observation equations and to improve estimation of DCB values. There are many factors affecting the estimated values of DCBs. The first one is the observation weighting function which depends on the satellite elevation angle. The second factor is concerned with estimating DCBs using a single GPS station using the Zero Difference DCB Estimation (ZDDCBE) code or using the GPS network used by the MSDCBE code. The third factor is the number of GPS receivers in the network. Results from MSDCBE were evaluated and compared with data from IAACs and other codes like M_DCB and ZDDCBE. The results of weighted (MSDCBE) least squares show an improvement for estimated DCBs, where mean differences from the Center for Orbit Determination in Europe (CODE) (University of Bern, Switzerland) are less than 0.746 ns. DCBs estimated from the GPS network show better agreement with IAAC than DCBs estimated from precise point positioning (PPP), where the mean differences are less than 0.1477 and 1.1866 ns, respectively. The mean differences of computed DCBs improved by increasing the number of GPS stations in the network.

Download Full-text

Evaluating home range techniques: use of Global Positioning System (GPS) collar data from chacma baboons

Primates ◽

10.1007/s10329-012-0307-5 ◽

2012 ◽

Vol 53 (4) ◽

pp. 345-355 ◽

Cited By ~ 15

Author(s):

Paula A. Pebsworth ◽

Hanna R. Morgan ◽

Michael A. Huffman

Keyword(s):

Home Range ◽

Global Positioning System ◽

Positioning System ◽

Gps Collar ◽

Global Positioning ◽

Chacma Baboons

Download Full-text

Iterative least squares method for global positioning system

Advances in Radio Science ◽

10.5194/ars-9-203-2011 ◽

2011 ◽

Vol 9 ◽

pp. 203-208 ◽

Cited By ~ 14

Author(s):

Y. He ◽

A. Bilgic

Keyword(s):

Linear System ◽

Least Squares ◽

Global Positioning System ◽

Least Squares Method ◽

Positioning System ◽

System Of Equations ◽

Linear System Of Equations ◽

Global Positioning ◽

Non Linear ◽

Non Linear System

Abstract. The efficient implementation of positioning algorithms is investigated for Global Positioning System (GPS). In order to do the positioning, the pseudoranges between the receiver and the satellites are required. The most commonly used algorithm for position computation from pseudoranges is non-linear Least Squares (LS) method. Linearization is done to convert the non-linear system of equations into an iterative procedure, which requires the solution of a linear system of equations in each iteration, i.e. linear LS method is applied iteratively. CORDIC-based approximate rotations are used while computing the QR decomposition for solving the LS problem in each iteration. By choosing accuracy of the approximation, e.g. with a chosen number of optimal CORDIC angles per rotation, the LS computation can be simplified. The accuracy of the positioning results is compared for various numbers of required iterations and various approximation accuracies using real GPS data. The results show that very coarse approximations are sufficient for reasonable positioning accuracy. Therefore, the presented method reduces the computational complexity significantly and is highly suited for hardware implementation.

Download Full-text

Gray Wolf (Canis lupus) Movements and Behavior Around a Kill Site and Implications for GPS Collar Studies

The Canadian Field-Naturalist ◽

10.22621/cfn.v125i4.1263 ◽

2012 ◽

Vol 125 (4) ◽

pp. 353 ◽

Cited By ~ 3

Author(s):

L. David Mech

Keyword(s):

Global Positioning System ◽

Canis Lupus ◽

Gray Wolf ◽

Positioning System ◽

Ovibos Moschatus ◽

Gps Collars ◽

Global Positioning ◽

Other Information ◽

Kill Site ◽

And Behavior

Global Positioning System (GPS) radio-collars are increasingly used to estimate Gray Wolf (Canis lupus) kill rates. In interpreting results from this technology, researchers make various assumptions about wolf behavior around kills, yet no detailed description of this behavior has been published. This article describes the behavior of six wolves in an area of constant daylight during 30 hours, from when the pack killed a Muskox (Ovibos moschatus) calf and yearling on Ellesmere Island, Nunavut, Canada, to when they abandoned the kill remains. Although this is only a single incident, it demonstrates one possible scenario of pack behavior around a kill. Combined with the literature, this observation supports placing a radio-collar on the breeding male to maximize finding kills via GPS collars and qualifying results depending on whatever other information is available about the collared wolf’s pack.

Download Full-text

Aplikasi Pemosisi Lokal Berbasis Android Dengan Menggunakan GPS

INTI TALAFA ◽

10.32534/int.v8i2.399 ◽

2018 ◽

Vol 8 (2) ◽

Author(s):

Yaman Khaeruzzaman

Keyword(s):

Global Positioning System ◽

Positioning System ◽

Database Server ◽

Global Positioning

Seiring dengan pesatnya kemajuan teknologi saat ini, kebutuhan manusia menjadi lebih beragam, termasuk kebutuhan akan informasi. Tidak hanya media informasinya yang semakin beragam, jenis informasi yang dibutuhkan juga semakin beragam, salah satunya adalah kebutuhan informasi akan posisi kita terhadap lingkungan sekitar. Untuk memenuhi kebutuhan itu sebuah sistem pemosisi diciptakan. Sistem pemosisi yang banyak digunakan saat ini cenderung berfokus pada lingkup ruang yang besar (global) padahal, dalam lingkup ruang yang lebih kecil (lokal) sebuah sistem pemosisi juga diperlukan, seperti di ruang-ruang terbuka umum (taman atau kebun), ataupun dalam sebuah bangunan. Sistem pemosisi lokal yang ada saat ini sering kali membutuhkan infrastruktur yang mahal dalam pembangunannya. Aplikasi Pemosisi Lokal Berbasis Android dengan Menggunakan GPS ini adalah sebuah aplikasi yang dibangun untuk memenuhi kebutuhan pengguna akan informasi lokasi dan posisi mereka terhadap lingkungan di sekitarnya dalam lingkup ruang yang lebih kecil (lokal) dengan memanfaatkan perangkat GPS (Global Positioning System) yang telah tertanam dalam perangkat smartphone Android agar infrastruktur yang dibutuhkan lebih efisien. Dalam implementasinya, Aplikasi Pemosisi Lokal ini bertindak sebagai klien dengan dukungan sebuah Database Server yang berfungsi sebagai media penyimpanan data serta sumber referensi informasi yang dapat diakses melalui jaringan internet sehingga tercipta sebuah sistem yang terintegrasi secara global. Kata kunci: aplikasi, informasi, pemosisi, GPS.

Download Full-text