Temat: ITU - Prolib Integro

Skocz do pozycji: 1.

Tytuł:: Statistical Estimation and Mathematical Modelling of Tropospheric Radio Refractivity Based on Meteorological Data
Autorzy:: Alimgeer, K. S.
Awais, M.
Ijaz, B.
Khan, S. A.
Subhan, F.
Ahmad, N.
Tematy:: radio refractivity
statistical estimation
ITU
mathematical modelling; Pokaż więcej
Wydawca:: Polska Akademia Nauk. Czytelnia Czasopism PAN
Powiązania:: https://bibliotekanauki.pl/articles/221069.pdf Link otwiera się w nowym oknie
Opis:: To obtain optimal performance, estimation of radio refractivity is essential in planning and design of radio links/systems. The dependence of radio refractivity on different climatic parameters such as temperature, pressure, humidity and scale height is studied. The method proposed by International Telecommunication Union (ITU) is used in calculation of tropospheric radio refractivity. The main objective of this work is to formulate a mathematical equation/expression which can be used to predict/estimate the value of radio refractivity for an arbitrary day of any year, with a low error of estimation, in a local environment. Sensitivity of radio refractivity to temperature, pressure and humidity has been evaluated for a period of 5 years from 2008 to 2012, in a particular area under consideration. The results presented for tropospheric radio refractivity take into consideration both the location height and scale height parameters. The results are analysed in terms of statistical measures such as the moving averages, probability density function, monthly mean values, and their corresponding standard deviations. Finally, a mathematical model is formulated to calculate the radio refractivity for any day of a whole year. Reliability of error analysis in respect to accuracy is also shown. It was implemented in the industrial enterprise.
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 2.

Tytuł:: Revising and Improving the ITU-T Recommendation P.912
Autorzy:: Leszczuk, M.
Tematy:: CCTV
ITU-T
P.912
QoE
QoS
TRV; Pokaż więcej
Wydawca:: Instytut Łączności - Państwowy Instytut Badawczy
Powiązania:: https://bibliotekanauki.pl/articles/308247.pdf Link otwiera się w nowym oknie
Opis:: It was once thought that high Quality of Service (QoS) performance solves recurrent problems of lowquality multimedia services. Since then, solutions have been proposed to ensure a high level of Quality of Experience (QoE). In this paper, the author attempts to outline an understanding of an accurate meaning of multimedia services quality. Starting from QoS and passing through generalized QoE, the author focuses on subjective aspects and objective quality modeling and optimization of visual performance for Target Recognition Video (TRV) applications (such as video surveillance), to outline the ITU-T standardization path in this area. The revising the ITU-T Recommendation P.912 is proposed to reflect improved subjective test techniques developed since this Recommendation was approved. Also at least some existing errors of reasoning are predicted, which are likely to become evident for the industry in the next decade. Finally, the author invites all researchers working on topics related to TRV to join him in the process of improving P.912.
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 3.

Tytuł:: Quantifying the Suitability of Reference Signals for the Video Streaming Analysis for IPTV
Autorzy:: Hoppe, C.
Manzke, R.
Rompf, M.
Uhl, T.
Tematy:: communication network
IPVT service
ITU-T J.247
measurement tools
PEVQ
QoS/QoE determination
reference signal
Triple Play Services
VQuad-HD
ITU-T J.341; Pokaż więcej
Wydawca:: Instytut Łączności - Państwowy Instytut Badawczy
Powiązania:: https://bibliotekanauki.pl/articles/307690.pdf Link otwiera się w nowym oknie
Opis:: IP networks are indispensable nowadays and they are some of the most efficient platforms. The constantly growing number of users and new services in these networks – the largest being the Internet – require a satisfactory quality of service from any application they use. So, determining the QoS in real-time services is particularly important. This work shows how to quantify the suitability of reference signals for analyzing the quality of video streaming in IPTV. The assessment relies on two different algorithms: PEVQ and VQuad-HD. Three different reference signals – two real ones and an artificial one – are used in this study, and a numerical measurement system is used, which simulates mean network impairments. These measurements provide valuable information for determining the QoS of actual IPTV services in practice.
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 4.

Tytuł:: Projects for the Regulation of Space Traffic Management
Autorzy:: Polkowska, Malgorzata
Toumi, Marzena
Tematy:: Space Traffic Management
ITU
UN COPUOS
Space Situational Awareness
space safety; Pokaż więcej
Wydawca:: Stowarzyszenie Absolwentów i Przyjaciół Wydziału Prawa Katolickiego Uniwersytetu Lubelskiego
Powiązania:: https://bibliotekanauki.pl/articles/55796008.pdf Link otwiera się w nowym oknie
Opis:: The elements of the STM regime are the two dimensions of space traffic (in the scientific-technical and regulatory domains) and the three phases of space traffic: the launch, the on-orbit operations and the return. Examples of traffic regulations include launch safety rules, a specific air-space regime, manned spacecraft safety rules, regulations governing debris removal, traffic laws for orbital phases, return safety regulations (e.g. descent corridors), frequency use and avoidance of interference, environmental regulations, etc. Implementation and control mechanisms are primarily national regulations for licensing, arbitration and enforcement, operational assessments, coordination, and civil-military cooperation. This article is based on the concept of STM, which emphasises the need to respond quickly to unexpected events in space by creating a regime that encompasses all aspects of space activities.
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 5.

Tytuł:: Kierunek rozwoju regulacji prawnych pojazdów autonomicznych w ramach prac Europejskiej Komisji Gospodarczej ONZ (UNECE) oraz Międzynarodowego Związku Telekomunikacyjnego (ITU)
Approaches for the development of legislation of autonomous vehicles in the works of the United Nations Economic Commission for Europe (UNECE) and the International Telecommunication Union (ITU)
Autorzy:: Rudnik, S.
Tematy:: pojazd autonomiczny
regulacje prawne
Europejska Komisja Gospodarcza ONZ
UNECE
kierunek rozwoju
Międzynarodowy Związek Telekomunikacyjny
ITU
autonomous vehicle
legislation
United Nations Economic Commission for Europe (UNECE)
International Telecommunication Union (ITU); Pokaż więcej
Wydawca:: Instytut Naukowo-Wydawniczy "SPATIUM"
Powiązania:: https://bibliotekanauki.pl/articles/314473.pdf Link otwiera się w nowym oknie
Opis:: Niniejszy artykuł ma na celu omówienie kierunku rozwoju regulacji prawnych odnoszących się do pojazdów autonomicznych. W pracy zostanie dokonana analiza pojęcia pojazdu autonomicznego w świetle obowiązujących regulacji prawa międzynarodowego publicznego. W sposób syntetyczny przedstawiony zostanie opis prac dotyczących planów tworzenia przepisów prawnych regulujących ruch pojazdów autonomicznych w pracach Europejskiej Komisji Gospodarczej Organizacji Narodów Zjednoczonych (UNECE) oraz Międzynarodowego Związku Telekomunikacyjnego (ITU).
Approaches for the development of legislation of autonomous vehicles in the works of the United Nations economic commission for Europe (UNECE) and the International Telecommunication Union (ITU) The purpose of this article is an attempt of describing the approaches for the development of legislation of autonomous vehicles (connected cars). The paper analyzes the definition of autonomous driving functioning in public international law, as well as it presents a description of the legislative plans regulating the autonomous vehicles in the works of the United Nations Economic Commission for Europe (UNECE) and the International Telecommunication Union (ITU).
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 6.

Tytuł:: New Tool for Examining QoS in the VToIP Service
Autorzy:: Uhl, T.
Nowicki, K.
Paulsen, S.
Tematy:: communication network
emulation tool
ITU-T G.1070
PEVQ
QoS measurement
Triple Play services
video streaming
VToIP; Pokaż więcej
Wydawca:: Instytut Łączności - Państwowy Instytut Badawczy
Powiązania:: https://bibliotekanauki.pl/articles/307757.pdf Link otwiera się w nowym oknie
Opis:: This paper is dedicated to the subject of measuring QoS in the Video Telephony over IP (VToIP) service. QoS measurement models in general and then models designed specifically for measuring QoS in the VToIP service are presented. A new numerical tool for examining the quality of VToIP video streams VToIP is described. The tool’s functionality is then put to the test in a number of analysis scenarios. The results and insights gained from the analyses are then presented in several diagrams, and interpreted. The paper concludes with a summary and an outlook on further areas of work.
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 7.

Tytuł:: Geostationary Belt – State’s Territory or Province of Mankind?
Autorzy:: Kopeć, Rafał
Wydawca:: Pracownia Badań nad Mniejszościami Narodowymi i Etnicznymi Instytutu Politologii Uniwersytetu Zielonogórskiego
Cytata wydawnicza:: Kopeć, R. (2018). Geostationary Belt – State’s Territory or Province of Mankind? Przegląd Narodowościowy, 8 (1) : 167–178.
Opis:: The geostationary orbit is a special area in outer space. Because of its distinctive characteristics, it has constantly been the subject of economic and political desirability. Space powers, taking advantage of their technological superiority and rules applied by the International Telecommunication Union (ITU) retained a privileged position. Developing countries, responding to this state of affairs, have taken a number of measures to improve their positions. Some of them posed a challenge to the main regulation of space law (Bogotá declaration was an attempt to exercise a national sovereignty over the segments of the geostationary orbit), some are based on the use of the legal gaps in ITU regulations. Given these circumstances, the specific case of geostationary belt contributes to the debate on the regulations governing space exploration.
Dostawca treści:: Repozytorium Centrum Otwartej Nauki

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Skocz do pozycji: 8.

Tytuł:: A New Parameterized Model for Determining Quality of Online Video Service Using Modern H.265/HEVC and VP9 Codecs
Autorzy:: Uhl, Tadeus
Hoppe, Christian
Tematy:: H.265/HEVC
IP network
ITU-T
J.341
native RTP
QoS measurement techniques
video services
VP9; Pokaż więcej
Wydawca:: Instytut Łączności - Państwowy Instytut Badawczy
Powiązania:: https://bibliotekanauki.pl/articles/1839313.pdf Link otwiera się w nowym oknie
Opis:: This paper describes a new measurement method (VS model) for determining the quality of online video services relying on modern H.265/HEVC and VP9 codecs. The said method has been developed on the basis of VQuad-HD curves (according to ITU-T J.341). This model does not refer to signal analysis, but protocol analysis instead. The parameters used are: type of video codec, encoding rate, transport technique, packet loss and burst size. The method may be implemented quickly and easily, which is one of the great advantages when using this method to measure QoS.
Dostawca treści:: Biblioteka Nauki

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na półce

Skocz do pozycji: 9.

Tytuł:: An Optimized Propagation Model based on Measurement Data for Indoor Environments
Autorzy:: Morocho-Yaguana, M.
Ludeňa-González, P.
Sandoval, F.
Poma-Vélez, B.
Erreyes-Dota, A.
Tematy:: indoor
ITU model
log-distance model
loss measurement
one-slope model
path loss
propagation measurements
propagation models
radio propagation; Pokaż więcej
Wydawca:: Instytut Łączności - Państwowy Instytut Badawczy
Powiązania:: https://bibliotekanauki.pl/articles/308451.pdf Link otwiera się w nowym oknie
Opis:: Propagation is an essential factor ensuring good coverage of wireless communications systems. Propagation models are used to predict losses in the path between transmitter and receiver nodes. They are usually deﬁned for general conditions. Therefore, their results are not always adapted to the behavior of real signals in a speciﬁc environment. The main goal of this work is to propose a new model adjusting the loss coeﬃcients based on empirical data, which can be applied in an indoor university campus environment. The Oneslope, Log-distance and ITU models are described to provide a mathematical base. An extensive measurement campaign is performed based on a strict methodology considering different cases in typical indoor scenarios. New loss parameter values are deﬁned to adjust the mathematical model to the behavior of real signals in the campus environment. The experimental results show that the model proposed oﬀers an attenuation average error of 2.5% with respect to the losses measured. In addition, comparison of the proposed model with existing solutions shows that it decreases the average error signiﬁcantly for all scenarios under evaluation.
Dostawca treści:: Biblioteka Nauki

Artykuł

na półce

Skocz do pozycji: 10.

Tytuł:: New Tool for Investigating QoS in the WWW Service
Autorzy:: Uhl, T.
Rompf, M.
Tematy:: Apdex index
communication network
ITU-T G.1030
measurement tools
Power metric
QoS/QoE determination
Triple Play Services
WWW service; Pokaż więcej
Wydawca:: Instytut Łączności - Państwowy Instytut Badawczy
Powiązania:: https://bibliotekanauki.pl/articles/307924.pdf Link otwiera się w nowym oknie
Opis:: The subject of this paper is the QoS measurement in the World Wide Web (WWW) service. It will begin with a brief presentation of methods currently used to measure QoS in the WWW service before going on to describe in detail the new tool QoSCalc (WWW). Following that, the potential of the new tool will be put to the test in a series of analysis scenarios. The results and insights obtained will then be presented in several diagrams, and interpreted.
Dostawca treści:: Biblioteka Nauki

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