Cellular networks

The Distribution system interconnects multiple BSSs. 802.11 standard logically separates the wireless medium from the distribution system – it does not preclude, nor demand, that the multiple media be same or different. An Access Point (AP) is a STA that provides access to the DS by providing DS services in addition to acting as a STA.

100p nammo0168 15-05-2011 124 33   Download

The modelling of traffic flow using methods and models from physics has a long history. In recent years especially cellular automata models have allowed for large-scale simulations of large traffic networks faster than real time. On the other hand, these systems are interesting for physicists since they allow to observe genuine nonequilibrium effects. Here the current status of cellular automata models for traffic flow is reviewed with special emphasis on nonequilibrium effects (e.g. phase transitions) induced by on- and off-ramps.

23p nguyenhaisu 07-08-2015 65 4   Download

Chương 6 giới thiệu về mạng không dây và mạng di động (Wireless and Mobile networks). Thông qua chương này người học có thể biết về kết nối không dây, IEEE 802.11 (Wi-Fi), truy cập cellular; hiểu được các nguyên lý: định địa chỉ, định tuyến tới người dùng di động; biết được các tác động lên các giao thức tầng cao hơn di động.

69p kiepnaybinhyen_04 15-12-2015 223 53   Download

Bài giảng "Mạng không dây - Chương 5: Mạng tế bào" trình bày các nội dung: Cellular network concept; cells, cluster and frequency reuse; handoff/Handover concept, Co-Channel interference and adjacent channel interference, erlang, erlang-B. Mời các bạn cùng tham khảo.

54p nguoibakhong02 19-03-2018 79 13   Download

Bài giảng "Lý thuyết mạng máy tính - Chương 7: Wireless và mobile network" cung cấp cho người học các kiến thức: Mạng wireless, CDMA, wifi, cellular internet access. Đây là một tài liệu hữu ích dành cho các bạn sinh viên ngành Công nghệ thông tin và những ai quan tâm dùng làm tài liệu học tập và nghiên cứu.

59p koxih_kothogmih2 23-08-2020 54 4   Download

Chapter 5 - Wireless security. After studying this chapter you will be able to understand: Wireless concepts, Securing digital cellular telephony, wireless application protocol, wireless transport layer security, hardening wireless local area networks, IEEE 802.11, wired equivalent privacy (WEP).

20p nhanmotchut_3 20-10-2016 68 4   Download

Metabolic fluxes provide a detailed metric of the cellular metabolic phenotype. Fluxes are estimated indirectly from available measurements and various methods have been developed for this purpose. Of particular interest are meth-ods making use of stable isotopic tracers as they enable the estimation of fluxes at a high resolution. In this paper, we present data validating the use of mass spectrometry (MS) for the quantification of complex metabolic flux networks.

18p tumor12 20-04-2013 45 2   Download

All higher organisms divide major biochemical steps into different cellular compartments and often use tissue-specific division of metabolism for the same purpose.Such spatial resolution is accompanied with temporal changes of meta-bolite synthesis in response to environmental stimuli or developmental needs.Although analyses of primary and secondary gene products, i.e. transcripts, proteins, and metabolites, regularly do not cope with this spatial and temporal resolution, these gene products are often observed to be highly coregulated forming complex networks....

10p tumor12 20-04-2013 37 2   Download

Due to the unavoidable nonbiological variations accompanying many experiments, it is imperative to consider a way of unravelling the functional interaction structure of a cellular network (e.g. signalling cascades or gene networks) by using the qualitative information of time-series experimental data instead of computation through the measured absolute values.

10p fptmusic 11-04-2013 52 3   Download

Our laboratory is interested in the biochemical and biophysical basis of cell structure. The structure of a cell is determined primarily by its cytoskeleton, which serves as a scaffold to sup-port the plasma membrane, and as a network of tracks along which motor proteins transport sub cellular structures. Our research is therefore focused on the mechanics of the cytoskele-ton, with a particular emphasis on microtubules and microtu-bule-based motors.

17p fptmusic 11-04-2013 54 3   Download

Cellular regulation is a result of complex interactions arising from DNA–protein and protein–protein binding, autoreg-ulation, and compartmentalization and shuttling of regula-tory proteins. Experiments in molecular biology have identified these mechanisms recruited by a regulatory net-work.Mathematicalmodelsmaybe used to complement the knowledge-base provided byin vitroexperimental methods. Interactions identified byin vitroexperiments can lead to the hypothesis of multiple candidate models explaining the in vivo mechanism. ...

11p awards 05-04-2013 53 3   Download

Cellular functions are ultimately linked to metabolic fluxes brought about by thousands of chemical reactions and transport processes. The synthesisof theunderlying enzymes and membrane transporters causes the cell a certain
effort of energyandexternal resources.Considering that those cells should have had a selection advantage during natural evo-lution that enabled them to fulfil vital functions (such as growth, defence against toxic compounds, repair of DNA alterations, etc.)

18p dell39 03-04-2013 34 5   Download

Patterns of protein interactions are organized around complex heterogene-ous networks. Their architecture has been suggested to be of relevance in understanding the interactome and its functional organization, which per-vades cellular robustness. Transcription factors are particularly relevant in this context, given their central role in gene regulation.

12p dell39 27-03-2013 39 3   Download

High-quality quantitative data generated under standardized conditions is critical for understanding dynamic cellular processes. We report strategies for error reduction, and algorithms for automated data processing and for establishing the widely used techniques of immunoprecipitation and immu-noblotting as highly precise methods for the quantification of protein levels and modifications.

12p dell39 27-03-2013 54 3   Download

Akt (also known as protein kinase B) plays an integral role in many intra-cellular signaling pathways activated by a diverse array of extracellular sig-nals that target several different classes of membrane-bound receptors. Akt plays a particularly prominent part in signaling networks that result in the modulation of cellular proliferation, apoptosis and survival.

12p media19 05-03-2013 33 2   Download

The vascular network of the brain is formed by the invasion of vascular sprouts from the pia mater toward the ventricles. Following angiogenesis of the primary vascular network, brain vessels experience a maturation pro-cess known as barriergenesis, in which the blood–brain barrier is formed.

14p vinaphone15 25-02-2013 34 3   Download

Protein kinases drive the cellular signal transduction networks that underlie the regulation of growth, survival and differentiation. To repair the deregu-lations of signaling cascades that are associated with numerous disease states, therapeutic strategies, based on controlling aberrant protein kinase activity, are emerging.

9p viettel02 20-02-2013 44 3   Download

Virtually every process in a cell is carried out by macromolecular com-plexes whose actions need to be perfectly orchestrated. The synchronization and regulation of these biological functions is indeed critical and is usually carried out by complex networks of transient protein interactions. Here, we review some of the many strategies that proteins in regulatory networks use to achieve the dynamic plasticity necessary to rapidly respond to diverse cellular needs.

16p viettel02 20-02-2013 35 4   Download

In this series of four minireviews the field of scaffold proteins and proteins of similar molecular⁄cellular functions is overviewed. By binding and bring-ing into proximity two or more signaling proteins, these proteins direct the flow of information in the cell by activating, coordinating and regulating signaling events in regulatory networks.

8p viettel02 19-02-2013 65 3   Download

Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Research Article A Utility-Based Downlink Radio Resource Allocation for Multiservice Cellular DS-CDMA Networks

11p sting11 09-03-2012 36 3   Download