Investigation on the Effect of GPS and GLONASS Constellation Use on the Accuracy of Point Positioning in PPP Method
Notice bibliographique
Résumé
After the completion of the GLONASS (GLObalnaya NAvigatsionnaya Sputnikovaya Sistema or GLObal NAvigation Satellite System) which was developed by Russian Federation and making it service as second running system all over the world after GPS, satellite based geodetic studies have been focused on integration of GPS and GLONASS systems. It is possible to determine the position and/or increase the accuracy and reliability by receiving more data from the satellites especially for the forested lands, urban canyons, open mine areas and valleys etc. which have inadequate number of satellites or weak signals. Nowadays, development in satellite technology and dazzling progress in data processing and analysis allows to point positioning within cm to dm level with only a single GNSS receiver. It is possible to make positioning by using the method called as Precise Point Positioning (PPP) in static or kinematic mode using precise orbit and clock data without being in need of any data other than collected with a single receiver. Until recently, PPP-derived coordinates were obtained by only scientific GNSS processing software but now it is possible to obtain a result with the software that universities or institutes coded or commercial software. However, all these programs require GNSS knowledge and generally requires licensing fee. Recently, many on-line PPP processing services which eliminates the disadvantages and have practical usage have been started to be used. One of these services, CSRS-PPP(Canadian Spatial Reference System-Precise Point Positioning) attracts attention with its accuracy and ease of use. In this study, static measurements were performed with the receivers which can collect data from GPS and GLONASS satellite systems at the geodetic points from intense residential areas in Çorum city region, mostly around the city center. Collected data was evaluated separately by GPS and by GPS+GLONASS integrated systems with CSRS-PPP service operated by Canada. The PPP-derived coordinates were compared with the ones obtained by differential method (accepted as accurate coordinates). In order to investigate the effect of Rapid and Final precise products (with have different latency) on the result, the data was uploaded to the system after finishing the measurements and again just after several weeks, and the results were compared. In this study, the test procedure and obtained results are discussed. Keywords : GPS, GLONASS, Precise Point Positioning (PPP), CSRS-PPP, on-line PPP.
Récupéré en direct depuis OpenAlex et désinversé. Les résumés ne sont pas conservés dans cette base de données : les index inversés représentent 8,6 Go des 9,3 Go de texte de la base, et le serveur dispose de 13 Go libres.
Comment cette classification a été obtenuedéplier
Prédiction machine sur la base complète
Imitation des enseignantsNi prévalence calibrée, ni vérité terrain. Validation humaine à venir. Le volet Gemma est une étiquette directe du modèle pour chaque travail de la base, lue sur la notice réduite au titre. Le volet Codex est un classifieur appris des 10 348 étiquettes directes de Codex et calibré sur les taux pondérés de l'échantillon; les champs sans appui suffisant ne portent aucun appel Codex. Le mode candidate est l'union des deux volets; le consensus est leur intersection. Ces sorties portent le statut machine_predicted_unvalidated et ne sont pas des étiquettes humaines.
Scores du classifieur distillé par catégorie (deux têtes)
| Catégorie | Codex | Gemma |
|---|---|---|
| Métarecherche | 0,002 | 0,014 |
| Méta-épidémiologie (sens strict) | 0,000 | 0,000 |
| Méta-épidémiologie (sens large) | 0,000 | 0,000 |
| Bibliométrie | 0,001 | 0,002 |
| Études des sciences et des technologies | 0,000 | 0,000 |
| Communication savante | 0,001 | 0,001 |
| Science ouverte | 0,001 | 0,001 |
| Intégrité de la recherche | 0,001 | 0,000 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,002 | 0,001 |
Scores machine (provisoires)
Les deux têtes enseignantes du modèle étudiant, lues sur ce travail. Un score ordonne la base pour la relecture; il n'affirme jamais une catégorie, et le statut de validation accompagne chaque rangée tel quel.
Scores de référence d'un modèle non mature (critères de maturité non atteints, 7 itérations). Un score ordonne; il n'affirme jamais une catégorie.
score_only:v0-immature-baseline · tel quel depuis la passe de notation : score_only signifie que le nombre peut ordonner les travaux, et qu'aucune étiquette de catégorie n'en découleClassification
machine, non validéePrédiction automatique; un appel candidat d’une seule source (Gemma direct ou Codex distillé), pas un consensus.
Le détail, modèle par modèle et score par score, se trouve en fin de page sous « Comment cette classification a été obtenue ».