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Využití změny skupenství při akumulaci tepla v solárních vzduchových systémech / Latent heat thermal storage in solar air systemsSúkup, Tomáš January 2012 (has links)
In this paper an overview is prepared for the possibility of heat accumulation in the use of heating and hot water. In the next section is designed heat accumulator uses PCM materials for solar air system. Its properties are experimentally verified.
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NETWORK CONNECTIONS BEYOND IEEE 802.11Zettwoch, Robert N. 10 1900 (has links)
International Telemetering Conference Proceedings / October 18-21, 2004 / Town & Country Resort, San Diego, California / More and more aircraft system designs are incorporating a local-area-network (LAN) using
either Fibre Channel (FC) or Ethernet. To date there hasn’t been a means for creating a FC node
connection between an airborne network and a ground based FC network or for creating a reliable
high-speed Ethernet connection between air and ground. Ethernet connections have had some
success by using the IEEE 802.11 wireless LAN for these types of connections; however, these
connections suffer from many inherent problems using this standard. Problems include the lack of
telemetry spectrum control, security validation, high-speed data transfer efficiency, and channel
acquisition time.
This paper will describe a methodology that utilizes the IRIG-106 PCM standard for
communicating between aircraft and ground-based networks. PCM can solve the aforementioned
problems and it enables the user to take advantage of the many ARTM advances in PCM telemetry
technology [1]. One such advance in technology has been the use of SOQPSK (Tier 1) or Multi-h
CPM (Tier 2) to enable the user to effectively double or more their bandwidth efficiency compared
to PCM/FM (or CPFSK) (Tier 0).
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WHY CHANGE FROM PCM? CASE STUDY OF THE AIRBUS A380 ETHERNET BASED DATA ACQUISITION NETWORKSweeney, Paul 10 1900 (has links)
ITC/USA 2005 Conference Proceedings / The Forty-First Annual International Telemetering Conference and Technical Exhibition / October 24-27, 2005 / Riviera Hotel & Convention Center, Las Vegas, Nevada / The adaptation of ubiquitous Ethernet technology to airborne FTI systems is a relatively recent
development, offering multiple advantages to FTI applications, including a high data throughput
and ability to integrate COTS equipment with ease.
For large-scale FTI applications – such as on the Airbus A380 - the use of traditional PCM based
data acquisition systems results in enormously complex system architectures, with difficulties in
system design, implementation, commissioning, test and maintenance. However, on the A380,
the use of the Ethernet-based, IENA protocol alleviated these problems, in addition to offering
several additional advantages.
This paper explores the theoretical and practical implications of using Ethernet-based data
acquisition in an FTI application, with direct comparison to an equivalent PCM based system.
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A 256 CHANNEL HIGH SPEED MODULAR FLIGHT COMPUTER FOR HYPERSONIC LAUNCH VEHICLESFinlayson, Simon, Paull, Allan 10 1900 (has links)
ITC/USA 2005 Conference Proceedings / The Forty-First Annual International Telemetering Conference and Technical Exhibition / October 24-27, 2005 / Riviera Hotel & Convention Center, Las Vegas, Nevada / Hypersonic test vehicles require extensive data acquisition in order to accurately determine and refine
engine performance. The increasing speed of scramjet engines places new constraints on data
manipulation and system control.
A compact modular flight computer has been developed that has high speed analog data acquisition, a
programmable high data rate PCM (Pulse Code Modulation) encoder, compact data storage, and high
speed I/O (Input/Output) capabilities. Principle to the design is the thermal management required for
space environments. A functional overview is presented together with a summary of the analog
performance. The integration of future capability requirements is also discussed.
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MINIATURE TELEMETRY SYSTEM FOR THE COMPACT KINETIC ENERGY MISSILEHaataja, M. Shannon, Ambrose, Mark 10 1900 (has links)
International Telemetering Conference Proceedings / October 18-21, 2004 / Town & Country Resort, San Diego, California / The Compact Kinetic Energy Missile (CKEM) is currently being developed as the Army’s newest
hypervelocity anti-tank missile. The project has recently transitioned from the Science and
Technology Objective phase to the Advanced Technology Demonstration phase. Science and
technology phase flight testing required the development of a miniature telemetry system for
measuring the super sonic flight dynamics of the airframe, as well as, monitoring of the on board
flight computer. Design challenges included a small mechanical envelope, limited power budget,
numerous analog measurements, computer serial stream processing, and harsh launch and flight
dynamics. Two versions of the system were developed in support of the partnership effort between
the Army Missile Research, Development, and Engineering Center (AMRDEC) and industry. This
paper will focus on the successful design, development, and flight tests of the CKEM telemetry
system.
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Extended Rasch Modeling: The eRm Package for the Application of IRT Models in RMair, Patrick, Hatzinger, Reinhold 22 February 2007 (has links) (PDF)
Item response theory models (IRT) are increasingly becoming established in social science research, particularly in the analysis of performance or attitudinal data in psychology, education, medicine, marketing and other fields where testing is relevant. We propose the R package eRm (extended Rasch modeling) for computing Rasch models and several extensions. A main characteristic of some IRT models, the Rasch model being the most prominent, concerns the separation of two kinds of parameters, one that describes qualities of the subject under investigation, and the other relates to qualities of the situation under which the response of a subject is observed. Using conditional maximum likelihood (CML) estimation both types of parameters may be estimated independently from each other. IRT models are well suited to cope with dichotomous and polytomous responses, where the response categories may be unordered as well as ordered. The incorporation of linear structures allows for modeling the effects of covariates and enables the analysis of repeated categorical measurements. The eRm package fits the following models: the Rasch model, the rating scale model (RSM), and the partial credit model (PCM) as well as linear reparameterizations through covariate structures like the linear logistic test model (LLTM), the linear rating scale model (LRSM), and the linear partial credit model (LPCM). We use an unitary, efficient CML approach to estimate the item parameters and their standard errors. Graphical and numeric tools for assessing goodness-of-fit are provided. (authors' abstract)
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ENHANCING THE PCM/FM LINK - WITHOUT THE MATHFewer, Colm, Wilmot, Sinbad 10 1900 (has links)
ITC/USA 2007 Conference Proceedings / The Forty-Third Annual International Telemetering Conference and Technical Exhibition / October 22-25, 2007 / Riviera Hotel & Convention Center, Las Vegas, Nevada / Since the 1970s PCM/FM has been the dominant modulation scheme used for RF telemetry.
However more stringent spectrum availability as well as increasing data rates means that
more advanced transmission methods are required to keep pace with industry demands.
ARTM Tier-I and Tier-II are examples of how the PCM/FM link can be enhanced. However
these techniques require a significant increase in the complexity of the receiver/detector for
optimal recovery.
This paper focuses on a quantitative approach to improving the rate and quality of data using
existing PCM/FM links. In particular ACRA CONTROL and BAE SYSTEMS set themselves
the goal of revisiting the pre-modulation filter, diversity combiner and bit-sync. By
implementing programmable adaptive hardware, it was possible to explore the various
tradeoffs offered by modifying pulse shapes and spectral occupancy, inclusion of forward
error correction and smart source selection. This papers looks at the improvements achieved
at each phase of the evaluation.
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SYSTEM DESIGN OF A HIGH DATA RATE WIDE BAND FM PCM INSTRUMENTATION AND TELEMETRY SYSTEM FOR INTERCEPTOR TEST FLIGHTSGoldsmith, T. A., Kephart, S. R. 10 1900 (has links)
International Telemetering Conference Proceedings / October 25-28, 1993 / Riviera Hotel and Convention Center, Las Vegas, Nevada / Given the small size of hit-to-kill interceptor test vehicles currently under development,
volumetric limitations mandate using the experimental vehicle's telemetry system during
vehicle ground level acceptance and environmental testing to gather performance data, in
addition to the primary function of successfully gathering and transmitting data during
the test flight. In small, lightweight test interceptors, volume and mass become major
telemetry system design considerations. In this paper we describe a system engineering
approach to determine the key requirements and calculate some of the critical design
parameters necessary for the successful design and development of a high data rate wide
band FM Pulse Code Modulation (PCM) airborne telemetry system.
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IRIG FQPSK-B STANDARDIZATION PROGRESS REPORTLaw, Eugene L. 10 1900 (has links)
International Telemetering Conference Proceedings / October 23-26, 2000 / Town & Country Hotel and Conference Center, San Diego, California / This paper will provide an overview of the process used to develop the bandwidth efficient modulation
sections of the Inter-Range Instrumentation Group (IRIG) standard. The modulation method selected
was Feher’s patented quadrature phase shift keying (FQPSK-B). The important characteristics of a
bandwidth efficient modulation method for aeronautical telemetry will be presented first followed by a
summary of the results of the research, laboratory test, and flight test efforts. Future plans will then be
summarized followed by the FQPSK-B sections of the current IRIG Telemetry Standard (the standard is
available online at: http://tecnet0.jcte.jcs.mil/RCC/oldoc.htm).
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CONFIGURING TELEMETRY SYSTEMS FOR HIGH-POWER-MICROWAVE TESTINGMeyer, Steven 11 1900 (has links)
International Telemetering Conference Proceedings / October 30-November 02, 1989 / Town & Country Hotel & Convention Center, San Diego, California / During high-power microwave (HPM) testing, where the item under test is subjected to power levels up to several thousand W/cm , the RF energy present will make typical 2 telemetry RF links useless. Therefore, other means must be used to retrieve the data during the tests. One method to accomplish data retrieval is to replace the RF data link with a fiber-optic link. This is done by replacing the transmitter with a fiber-optic transmitter on the sending end and the RF receiver with a fiber-optic receiver on the receiving end. Although this sounds simple, it is not always so. Solutions for PCM and FM-FM systems are relatively straightforward, whereas PAM systems present a unique set of problems. This paper addresses possible solutions for PCM and FM-FM and three possible solutions for PAM, one being by using a PAM-to-PCM converter.
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