Wyniki wyszukiwania - BazTech

1

Jak przebiega wycofywanie czynników HFC w Polsce − analiza danych z baz CRO i BDS

Kozakiewicz Janusz, Goworek Patrycja, Oksiuta Eliza

Chłodnictwo i Klimatyzacja

|

2022

|

nr 8

26, 28, 30--32

PL

Co wynika z danych dostępnych w bazach BDS i CRO? Czy nastąpił spadek ilości czynników chłodniczych na bazie HFC przywożonych do Polski i wywożonych z Polski luzem oraz w urządzeniach? Jakie są tendencje? Co niepokoi, co wskazuje na potrzebę podjęcia działań? Jak się do tego mają kolejne przepisy wprowadzane przez UE? Na te i inne pytania podjęli się poszukać odpowiedzi autorzy tego artykułu.

2

Incorporating Inter‑System Bias in Single Point Positioning Based on GPS, Galileo and BeiDou System

Kwaśniak Dawid Łukasz, Cellmer Sławomir

Geomatics and Environmental Engineering

|

2021

|

Vol. 15, no. 1

97--109

EN

The increasing number of satellites provides new opportunities. In the experiment presented in this paper, the Single Point Positioning technique is test ed. Data from four different receivers were used in the tests. The GPS, Galileo and BeiDou System observations were collected over a three day long observational session. The computational process was carried out using self made software and point positions were obtained as the result. The goal of the test was to verify the impact of the Inter System Bias (ISB) on the final results. For this purpose, two cases of processing data were compared: with estimating ISB and without taking into account this parameter. In the paper the formulas of the mathematical models used are presented and, in both of the considered cases, a combination of GPS, BDS and Galileo was used. The results show that in the case where the ISB was taken into account, the accuracy and precision in the positioning was much better than in the approach where the ISB was not considered. Estimating the ISB allows for more precise positioning results to be obtained for car navigation or GIS purposes.

3

Performance analysis of GPS/BDS integrated precise positioning system considering visibility of satellites

Noh Jae Hee, Jo Gwang Hee, Lim Deok Won, Lee Jin Hyuk, Lee Sun Yong, Lee Sang Jeong

Annual of Navigation

|

2019

|

No. 26

65--75

EN

Research on precise positioning is being actively carried out to provide accurate position information for land transportation. The most significant problem when performing precise positioning in urban canyon is the degradation of performance due to the lack of visible satellites. Prior to open service of BDS, most of the studies on positioning were focused on using GPS/GLONASS integrated navigation system. Since BDS began open service, studies using GPS/BDS have been actively performed in the Asia-Pacific region as it became possible to acquire enough available BDS satellites. The average number of visible satellites in Korea is 9 for GPS and 14 for BDS. In this paper, we analyze the availability of precise positioning using BDS in urban canyon. To do this, we simulate the urban canyon environment by applying the mask to the azimuth and the elevation. We analyze the positioning accuracy using two simulation scenarios. From the results, it is shown that the accuracy of precise positioning in the case where the satellites in the east-west direction are blocked is lowered than that in the case where the satellites in the south-north direction are blocked for the same elevation mask angle. This result comes from the fact that the PDOP increases when the satellites are blocked in the east-west direction. Also, it can be confirmed that the GPS/BDS integrated positioning is available for the high mask angle while the GPS-only positioning is not possible continuously.

4

Implementation of quasi real time estimation of BDS clock

Ning Wei, Wang Jian-Bo, Tang Long-Jiang

Acta Geophysica

|

2019

|

Vol. 67, no. 4

1131--1138

EN

To obtain high reliability and accuracy of the zenith tropospheric delay more quickly, this study describes a parameter estimation method that uses an epoch-differenced and undifferenced function model to estimate the clock of the BeiDou navigation satellite system (BDS)/global positioning system (GPS) satellites using a quasi-real-time process. Forty-five MGEX tracking stations distributed globally were selected for study. The initial orbit information of the clock estimation used the ultra-rapid orbit products released by the German Research Center for Geosciences and post-products as reference values. The experimental results showed that the accuracy of the GPS satellite clock was better than 0.06 ns. The precision of clock for three kinds of BDS satellites was between 0.04 and 0.08 ns, slightly worse than the GPS. The estimated BDS clock appears to meet the demands for computing the quasi-real-time zenith tropospheric delay.

5

Nieliniowa dynamika indeksów giełdowych WIG20 i ATX: analiza porównawcza

Gurgul H., Suder M

Ekonomia Menedżerska

|

2010

|

nr 7

103-120

PL

W pracy przedstawiono wyniki badań nad identyfikacją struktur nieliniowych oraz chaosu deterministycznego występujących na giełdzie austriackiej i polskiej. Biorąc za przykład indeksy ATX oraz WIG20 z okresu I 2001-VIIl 2008 oraz wykorzystując najbardziej popularne metody statystyczne wykrywania chaosu, wykazano, że w badanych szeregach występują struktury nieliniowe. Uzyskane wyniki wskazały, że w obydwu przypadkach mamy do czynienia z układami chaotycznymi, jednak liczbę zmiennych dynamicznych (wymiar korelacyjny), potrzebnych do opisania układu dla obydwu indeksów różnią się nieznacznie. Dla ATX wynosi ona 6, a dla WIG20 7. Przeprowadzona analiza wykazała również niewielkie różnice w długości cykli nieokresowych.

EN

This paper contains results of research concentrated at identification of nonlinear structures and deterministic chaos occurring on Austrian and Polish stock market. Taking into consideration the ATX and WIG20 indices from period I 2001-VIII 2008 and using the most popular statistical methods of uncovering the existence of chaos in nonlinear structures was indicated. Our results confirmed that in both considered cases chaos systems exist, however the number of dynamic variables required to describe the system for each index vary subtly. This value equals 6 for ATX and 7 for WIG20. Conducted analysis also brought evidence of small differences in length of nonperiodic cycles.