Gotowa bibliografia na temat „Four channel multicasting”

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Artykuły w czasopismach na temat "Four channel multicasting"

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Liu, Lan, Zhi Tong, Andreas O. J. Wiberg, Bill P. P. Kuo, Evgeny Myslivets, Nikola Alic i Stojan Radic. "Digital multi-channel stabilization of four-mode phase-sensitive parametric multicasting". Optics Express 22, nr 15 (22.07.2014): 18379. http://dx.doi.org/10.1364/oe.22.018379.

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Lan Liu, Andreas O. J. Wiberg, Evgeny Myslivets, Bill P. P. Kuo, Nikola Alic i Stojan Radic. "Suppression of Inter-channel Higher Order Four Wave Mixing in Four-Mode Phase-Sensitive Parametric Wavelength Multicasting". Journal of Lightwave Technology 33, nr 11 (1.06.2015): 2324–31. http://dx.doi.org/10.1109/jlt.2015.2391187.

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Hwang, Duckdong, Sung Sik Nam, Janghoon Yang i Hyoung-Kyu Song. "Intelligent-Reflecting-Surface-Assisted Multicasting with Joint Beamforming and Phase Adjustment". Applied Sciences 13, nr 1 (28.12.2022): 386. http://dx.doi.org/10.3390/app13010386.

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In this paper, a set of transmission schemes are proposed for the delivery of multicast (MC) signals, in which an intelligent reflecting surface (IRS) assists the transmission from an access point (AP) to a set of multicast users. It is known that the large number of IRS reflecting elements have the potential to improve the transmission efficiency by forming an artificial signal path with strong channel gain. However, the joint optimization of the AP beamformer and the phases of the IRS reflecting elements is challenging due to the non-convex nature of the phase elements as well as the high computational complexity required for a large number of elements. A set composed of two AP beamformer schemes and a set with two IRS phase adjustment algorithms are proposed, which are sub-optimal but less computationally demanding. A semi-definite relaxation (SDR)-based scheme is considered along with a least squares (LS) based one for the AP beamformer design. For the IRS phase adjustment, an LS based optimization and a grouping method for the phase elements are suggested. From these two sets, four combinations of overall optimization can be built, and their performances can be compared with their merits and weaknesses revealed. The signal-to-interference-plus-noise power ratio (SINR) performance results are verified in various parameter conditions by simulation.
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Rozprawy doktorskie na temat "Four channel multicasting"

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Pandey, Awanish. "Mode Engineering in Micro Ring Resonators and Their Application". Thesis, 2018. https://etd.iisc.ac.in/handle/2005/4666.

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Silicon Photonics (SiP) has emerged as the prominent platform for Photonic Integrated Circuits (PICs). CMOS technology compatible fabrication processes, high index contrast of the waveguide core-cladding leading to sharp bends, and low propagation loss are the key advantageous features of SiP circuits in Silicon on Insulator (SOI). Various functional units are already in their mature stage where Micro Ring Resonators (MRRs) have been widely used to realize wavelength selective devices in a PIC. Compact design, high Q-Factor, scalable spectral properties, and the ability to create complex higher-order signal processing architectures are some of its basic advantages. Due to these benefits of MRR, it has found a wide range of applications ranging from sensors, optical communication, and filters. MRRs resonate at particular resonance wavelengths dictated by the interference condition. However, fabrication imperfections and parasitic coupling at various interfaces in MRR excite undesirable degenerate cavity modes that can lead to unpredictable resonance splitting. The extent of splitting and the shape of split resonances are uncontrollable and unpredictable within a reasonable degree of accuracy and are only identified during the device characterization stage. Such split response limits the use of MRR, otherwise a versatile component in PIC. In this work, we attempted to tackle the resonance splitting problem by engineering mode interaction within the cavity. We proposed and demonstrated a unique Self-Coupled MRR (SCMRR) that provides a predictable and controllable resonance split by regulating the excitation of the degenerate cavity mode. We also worked over multiple cavity systems like loaded MRR and quadruple resonance split MRR to gain control over not only the extent of splitting but also the resonance shape. Finally, the proposed devices were exploited for applications in three different domains i.e. sensing, optical communication and RF signal processing using photonics. Optical Communication: we demonstrated four channel multicasting at 48Gbps (4 x12 Gbps) by selectively splitting the MRR resonance into four notches. Multicasting is achieved using Two Photon Absorption (TPA) induced Free Carrier Dispersion (FCD) in Silicon. To the best of our knowledge, we achieved the highest data rate/channel of 12 Gbps using a MRR based device. Sensing: we demonstrated an on-chip self-calibrated sensor interrogator. In this patented technique, we used SCMRR as an interrogator to scan the shift in FBG sensor spectrum that can automatically calibrate the system performance against the natural decay of the SCMRR thermal tuners and fluctuations in the ambient environment. Unlike a single MRR, SCMRR interrogator response certain spectral characteristics that can be processed to identify the change in FBG spectrum as well as the SCMRR resonance split. The SCMRR split is then fed back to the system to calibrate the thermal tuners for SCMRR. RF signal processing using photonics: we proposed a RF Phase Shifter (PS) and generation of on-chip Single SideBand with carrier (SSB+C) for Radio over Fiber (RoF) based applications. In PS, we achieved continuous tuning of RF phase from 00 to 1800 with a record low power penalty of sub-1dB for a wide bandwidth RF (8 GHz-43 GHz). In RoF, we proposed a method of generating SSB+C signal by suppressing one of the sidebands of a Double SideBand with Carrier (DSB+C) signal. We achieved a tunable suppression ratio, high dynamic range, and almost zero dispersion-based power penalty, unlike DSB+C signals, over a transmission length of 43 Km and a frequency range of 1 GHz-20 GHz. The suppression is achieved using DSB+C signal from bulk modulator as well as an on-chip modulator
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Ho, James Ching-Chih. "Logical Superposition Coded Modulation for Wireless Video Multicasting". Thesis, 2009. http://hdl.handle.net/10012/4323.

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This thesis documents the design of logical superposition coded (SPC) modulation for implementation in wireless video multicast systems, to tackle the issues caused by multi-user channel diversity, one of the legacy problems due to the nature of wireless video multicasting. The framework generates a logical SPC modulated signal by mapping successively refinable information bits into a single signal constellation with modifications in the MAC-layer software. The transmitted logical SPC signals not only manipulatively mimic SPC signals generated by the superposition of multiple modulated signals in the conventional hardware-based SPC modulation, but also yield comparable performance gains when provided with the knowledge of information bits dependencies and receiver channel distributions. At the receiving end, the proposed approach only requires simple modifications in the MAC layer software, which demonstrates full decoding compatibility with the conventional multi-stage signal-interference cancellation (SIC) approach involving additional hardware devices. Generalized formulations for symbol error rate (SER) are derived for performance evaluations and comparisons with the conventional hardware-based approach.
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Części książek na temat "Four channel multicasting"

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Ravindran, K. "Communication Channels for Data Multicasting in Multi-service Networks". W Computer Networks, Architecture and Applications, 124–45. Boston, MA: Springer US, 1995. http://dx.doi.org/10.1007/978-0-387-34887-2_8.

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AL-Suhail, Ghaida A., Liansheng Tan i Rodney A. Kennedy. "A Cross-Layer Model for Video Multicast Based TCP-Adaptive FEC over Heterogeneous Networks". W Networking and Telecommunications, 1879–95. IGI Global, 2010. http://dx.doi.org/10.4018/978-1-60566-986-1.ch119.

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In this article, we present a simple cross-layer model that leads to the optimal throughput of multiple users for multicasting MPEG-4 video over a heterogeneous network. For heterogeneous wired-to-wireless network, at the last wireless hop there are bit errors associated with the link-layer packets that are arising in the wireless channel, in addition of overflow packet dropping over wired links. We employ a heuristic TCP function to optimize the cross-layer model of data link and physical (radio-link) layer. An adaptive Forward-Error-Correction (FEC) scheme is applied at the byte-level as well as at the packet-level. The corresponding optimal video quality can be evaluated at each client end. The results show that a server can significantly adapt to the bandwidth and FEC codes to maximize the video quality of service (QoS) in terms of temporal scaling when a maximum network throughput for each client is reached.
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Das, Indrani, i Sanjoy Das. "Geocast Routing Protocols for Ad-Hoc Networks". W Cloud-Based Big Data Analytics in Vehicular Ad-Hoc Networks, 23–45. IGI Global, 2021. http://dx.doi.org/10.4018/978-1-7998-2764-1.ch002.

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Geocasting is a subset of conventional multicasting problem. Geocasting means to deliver a message or data to a specific geographical area. Routing refers to the activities necessary to route a message in its travel from source to the destination node. The routing of a message is very important and relatively difficult problems in the context of Ad-hoc Networks because nodes are moving very fast, network load or traffic patterns, and topology of the network is dynamical changes with time. In this chapter, different geocast routing mechanisms used in both Mobile Ad-hoc Networks and Vehicular Ad-hoc Networks. The authors have shown a strong and in-depth analysis of the strengths and weaknesses of each protocol. For delivering geocast message, both the source and destination nodes use location information. The nodes determine their locations by using the Global Positioning System (GPS). They have presented a comprehensive comparative analysis of existing geocast routing protocols and proposed future direction in designing a new routing protocol addressing the problem.
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Osawa, Noritaka, i Kikuo Asai. "Multipoint Multimedia Conferencing System for Efficient and Effective Remote Collaboration". W Advances in Distance Education Technologies, 126–46. IGI Global, 2010. http://dx.doi.org/10.4018/978-1-60566-934-2.ch009.

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A multipoint, multimedia conferencing system called FocusShare is described. It uses IPv6/IPv4 multicasting for real-time collaboration, enabling video, audio, and group-awareness and attention-sharing information to be shared. Multiple telepointers provide group-awareness information and make it easy to share attention and intention. In addition to pointing with the telepointers, users can add graphical annotations to video streams and share them with one another. The system also supports attention-sharing using video processing techniques. FocusShare is a modularly designed suite consisting of several simple tools, along with tools for remotely controlling them. The modular design and flexible management functions enable the system to be easily adapted to various situations entailing different numbers of displays with different resolutions at multiple sites. The remote control tools enable the chairperson or conference organizer to simultaneously change the settings for a set of tools distributed at multiple sites. Evaluation showed that the implemented attention-sharing techniques are useful: FocusShare was more positively evaluated than conventional video conferencing systems.
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Borgy Waluyo, Agustinus, David Taniar i Bala Srinivasan. "Mobile Information Systems in a Hopsital Organization Setting". W Handbook of Research on Advances in Health Informatics and Electronic Healthcare Applications, 493–523. IGI Global, 2010. http://dx.doi.org/10.4018/978-1-60566-030-1.ch030.

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The emerging of wireless computing motivates radical changes of how information is obtained. Our paper discusses a practical realisation of an application using push and pull based mechanism in a wireless ad-hoc environment. We use a hospital information system as a case study scenario for our proposed application. The pull mechanism is initiated from doctors as mobile client to retrieve and update patient records in the central database server. The push mechanism is initiated from the server without a specific request from the doctors. The application of push mechanism includes sending a message from central server to a specific doctor, and multicasting a global message to all doctors connected to the server application. The global message can be disabled by each doctor to perform selective recipients.
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Waluyo, Agustinus Borgy, David Taniar i Bala Srinivasan. "Mobile Information Systems in a Hospital Organization Setting". W Business Data Communications and Networking, 151–86. IGI Global, 2007. http://dx.doi.org/10.4018/978-1-59904-274-9.ch007.

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The emerging of wireless computing motivates radical changes of how information is obtained. Our paper discusses a practical realisation of an application using push and pull based mechanism in a wireless ad-hoc environment. We use a hospital information system as a case study scenario for our proposed application. The pull mechanism is initiated from doctors as mobile client to retrieve and update patient records in the central database server. The push mechanism is initiated from the server without a specific request from the doctors. The application of push mechanism includes sending a message from central server to a specific doctor, and multicasting a global message to all doctors connected to the server application. The global message can be disabled by each doctor to perform selective recipients.
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Hosszú, Gábor. "Reliability Issues of the Multicast-Based Mediacommunication". W Encyclopedia of Multimedia Technology and Networking, Second Edition, 1215–23. IGI Global, 2009. http://dx.doi.org/10.4018/978-1-60566-014-1.ch165.

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The multimedia applications generally support one-tomany group communication. Multicasting decreases the communication costs for applications, which send the same data to multiple receivers. Table 1 summarizes the types of the communication among the hosts. Currently, there is an increasing need for scalable and efficient group communication. Theoretically, multicasting is optimal for such purposes. Therefore, this technology is an emerging media dissemination technology, instead of the traditional unicast communication. It has two important types: the networklevel, namely IP-multicast, and the Application-Layer, host-multicast. In the former one, the data packets are delivered by the IP protocol, from one host to many hosts that are member of a multicast group. The routers run an IP-multicast routing protocol in order to construct a multicast tree. Along this tree, the data is forwarded to each host. Special IP addresses (224.0.0.0 - 239.255.255.255 address range) are used, which do not belong to hosts, but rather define multicast channels. In the case of Application-Layer Multicast (ALM), the hosts use unicast IP delivery, and the routers do not play any special role. Reliability is one of the most important features of all multimedia applications, independently from the multicast technology in use. This requirement is especially critical in the case of multicast, where the large volume of data is to be transferred, and correction or resending of lost data is even more difficult in time. In the multicast technology, the maintenance of the group membership information is also an important question from the point of view of the robustness of the so-called multicast delivery tree. The root of the tree is the sender, the leaves are the receivers, and the intermediate nodes are the routers in case of the IP-multicast. In the following sections, the reliability properties of different multicast technologies are overviewed.
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Al-Suhail, Ghaida A., Martin Fleury i Salah M. Saleh Al-Majeed. "Mobile Video Streaming Over Heterogeneous Networks". W Innovations in Mobile Multimedia Communications and Applications, 175–200. IGI Global, 2011. http://dx.doi.org/10.4018/978-1-60960-563-6.ch013.

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All-IP networks are under development with multimedia services in mind. Video multicast is an efficient way to deliver one video simultaneously to many users over such heterogeneous wired-to-wireless networks, such as in wireless IP applications where a mobile terminal communicates with an IP server through a wired IP network in tandem with a wireless network. Unicast video streaming is also an attractive way to deliver time-shifted TV to mobile devices. This Chapter presents a simple cross-layer model that leads to the optimal throughput to multiple users for multicasting video over a heterogeneous network. An adaptive forward-error-correction scheme is applied at the byte-level as well as at the packet-level to reduce channel errors. The results show that a server can significantly adapt to the bandwidth and FEC codes to maximize the video quality of service. For unicast streaming, the Chapter presents a single negative acknowledgment scheme in which a video stream is transmitted over a heterogeneous network from a streaming server to a mobile device in a WiMAX network. The broadband streaming system is compared to several candidate solutions based on originally wired network congestion controllers. Multi-connection streaming is also investigated.
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Al-Suhail, Ghaida A., Martin Fleury i Salah M. Saleh Al-Majeed. "Mobile Video Streaming Over Heterogeneous Networks". W Wireless Technologies, 737–63. IGI Global, 2012. http://dx.doi.org/10.4018/978-1-61350-101-6.ch315.

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All-IP networks are under development with multimedia services in mind. Video multicast is an efficient way to deliver one video simultaneously to many users over such heterogeneous wired-to-wireless networks, such as in wireless IP applications where a mobile terminal communicates with an IP server through a wired IP network in tandem with a wireless network. Unicast video streaming is also an attractive way to deliver time-shifted TV to mobile devices. This Chapter presents a simple cross-layer model that leads to the optimal throughput to multiple users for multicasting video over a heterogeneous network. An adaptive forward-error-correction scheme is applied at the byte-level as well as at the packet-level to reduce channel errors. The results show that a server can significantly adapt to the bandwidth and FEC codes to maximize the video quality of service. For unicast streaming, the Chapter presents a single negative acknowledgment scheme in which a video stream is transmitted over a heterogeneous network from a streaming server to a mobile device in a WiMAX network. The broadband streaming system is compared to several candidate solutions based on originally wired network congestion controllers. Multi-connection streaming is also investigated.
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Yang, Zhonghua, Yanyan Yang, Yaolin Gu i Robert Gay. "Integrated-Services Architecture for Internet Multimedia Applications". W Encyclopedia of Information Science and Technology, First Edition, 1549–54. IGI Global, 2005. http://dx.doi.org/10.4018/978-1-59140-553-5.ch273.

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The Internet has gone from near invisibility to near ubiquity and penetrated into every aspect of society in the past few years (Department of Commerce, 1998). The application scenarios have also changed dramatically and now demand a more sophisticated service model from the network. In the early 1990s, there was a large-scale experiment in sending digitized voice and video across the Internet through a packet-switched infrastructure (Braden, Clark, & Shenker, 1994). These highly visible experiments have depended upon three enabling technologies: (a) Many modern workstations now come equipped with built-in multimedia hardware, (b) IP multicasting, which was not yet generally available in commercial routers, is available, and (c) highly sophisticated digital audio and video applications have been developed. It became clear from these experiments that an important technical element of the Internet is still missing: Real-time applications often do not work well across the Internet. The Internet, as originally conceived, offers only a very simple quality-of-service (QoS), point-to-point, best-effort data delivery. However, for a real-time application, there are two aspects of the problem with using this service model. If the sender and/or receiver are humans, they simply cannot tolerate arbitrary delays; on the other hand, if the rate at which video and audio arrive is too low, the signal becomes incomprehensible. To support real-time Internet applications, the service model must address those services that relate most directly to the time of delivery of data. Real-time applications like video and audio conferencing typically require stricter guarantees on throughput and delay. The essence of real-time service is the requirement for some service guarantees in terms of timing. In response to these demands of real-time multimedia applications, the Internet Engineering Task Force (IETF) has significantly augmented the Internet protocol stack based on the Internet integrated-services model, which is the focus of this article.
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Streszczenia konferencji na temat "Four channel multicasting"

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Souza, Mario C., Luis A. M. Barea, Felipe Vallini, Guilherme F. M. Rezende, Gustavo S. Wiederhecker i Newton C. Frateschi. "Low-power four-channel wavelength multicasting in embedded microring resonators". W CLEO: Science and Innovations. Washington, D.C.: OSA, 2014. http://dx.doi.org/10.1364/cleo_si.2014.sw3m.6.

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Pandey, Awanish, i Shankar Kumar Selvaraja. "Four channel 48Gbps Multicasting in a Coupled Si Ring Resonator with Tunable Channel Spacing". W Conference on Lasers and Electro-Optics/Pacific Rim. Washington, D.C.: OSA, 2018. http://dx.doi.org/10.1364/cleopr.2018.w2d.4.

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Tong, Z., L. Liu, A. O. J. Wiberg, V. Ataie, E. Myslivets, B. Kuo, N. Alic i S. Radic. "First Demonstration of Four-Mode Phase-Sensitive Multicasting of Optical Channel". W CLEO: Science and Innovations. Washington, D.C.: OSA, 2013. http://dx.doi.org/10.1364/cleo_si.2013.cth5d.6.

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Chiew Tuan Kiang, Georgios Papadakis i Georgios Avdikos. "Satellite-terrestrial broadcasting/multicasting systems: Channel modelling and scalable video coding approach". W 2008 10th International Workshop on Signal Processing for Space Communications (SPSC). IEEE, 2008. http://dx.doi.org/10.1109/spsc.2008.4686696.

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Abdullah Al Masrur, Md, A. S. M. Badrudduza, Md Shakhawat Hossen, Milton Kumar Kundu i Md Zahurul Islam Sarkar. "Multicasting over Fisher Snedecor F Fading Channel: A Physical Layer Security Analysis". W 2021 International Conference on Automation, Control and Mechatronics for Industry 4.0 (ACMI). IEEE, 2021. http://dx.doi.org/10.1109/acmi53878.2021.9528233.

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Lim, Sung-Hwa, Cheolgi Kim, Young-Bae Ko i Nitin H. Vaidya. "Efficient multicasting for multi-channel multi-interface wireless mesh networks". W MILCOM 2009 - 2009 IEEE Military Communications Conference. IEEE, 2009. http://dx.doi.org/10.1109/milcom.2009.5379798.

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Kikuchi, Keiko, Toshihiro Tsuchida, Katsuhiko Kawazoe i Hiroshi Kazama. "Channel Assignment Control Method for Direct-Multicasting Satellite Communications System". W 21st International Communications Satellite Systems Conference and Exhibit. Reston, Virigina: American Institute of Aeronautics and Astronautics, 2003. http://dx.doi.org/10.2514/6.2003-2335.

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Boumard, Sandrine. "Resource Efficient Relaying for Multicasting Transmissions over Radio Channels". W 2020 IEEE 31st Annual International Symposium on Personal, Indoor and Mobile Radio Communications. IEEE, 2020. http://dx.doi.org/10.1109/pimrc48278.2020.9217364.

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Abdelkader, Ahmed, Imran Wajid, Alex B. Gershman i Nicholas D. Sidiropoulos. "Transmit beamforming for wireless multicasting using channel orthogonalization and local refinement". W ICASSP 2009 - 2009 IEEE International Conference on Acoustics, Speech and Signal Processing. IEEE, 2009. http://dx.doi.org/10.1109/icassp.2009.4960075.

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Sumona, A. S., M. K. Kundu, A. S. M. Badrudduza i M. Z. I. Sarkar. "Security Against Multiple Eavesdroppers for Multicasting Over Nakagami-q Fading Channel". W 2019 3rd International Conference on Electrical, Computer & Telecommunication Engineering (ICECTE). IEEE, 2019. http://dx.doi.org/10.1109/icecte48615.2019.9303535.

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