WorldWideScience

Sample records for mac address filtering

  1. Discussion on relationship between Ethernet MAC address and IP address%浅谈以太网中MAC地址与IP地址的关系

    Institute of Scientific and Technical Information of China (English)

    弓有辉

    2013-01-01

    从以太网体系结构入手,重点阐述了以太网数据链路层的作用与功能,并引入了MAC地址的概念,分别介绍了MAC地址与IP地址的作用与功能.从而重点阐述了计算机网络中IP地址与以太网MAC地址的相互关系和作用.%This paper starts from the Ethemet architecture,focusing on the role and function of Ethemet data link layer,and describes the concept of MAC address,respectively describes the function of MAC address and IP address.It focuses on the relationship and interaction between computer network IP address and MAC address of the Ethernet.

  2. Neutrino mass sensitivity by MAC-E-Filter based time-of-flight spectroscopy with the example of KATRIN

    CERN Document Server

    Steinbrink, Nicholas; Martin, Eric L; Robertson, R G Hamish; Zacher, Michael; Weinheimer, Christian

    2013-01-01

    The KATRIN experiment aims at a measurement of the neutrino mass with a 90 % C.L. sensitivity of 0.2 eV/c$^2$ by measuring the endpoint region of the tritium $\\beta$ decay spectrum from a windowless gaseous molecular tritium source using an integrating spectrometer of the MAC-E-Filter type. We discuss the idea of using the MAC-E-Filter in a time-of-flight mode (MAC-E-TOF) in which the neutrino mass is determined by a measurement of the electron time-of-flight (TOF) spectrum that depends on the neutrino mass. MAC-E-TOF spectroscopy here is a very sensitive method since the $\\beta$-electrons are slowed down to distinguishable velocities by the MAC-E-Filter. Their velocity depends strongly on their surplus energy above the electric retarding potential. Using MAC-E-TOF, a statistical sensitivity gain is expected. Because a small number of retarding-potential settings is sufficient for a complete measurement, in contrast to about 40 different retarding potentials used in the standard MAC-E-Filter mode, there is a ...

  3. Design and Implementation of MAC Address Comparison Burning Comparison Protocol Document%MAC地址烧录比对协议文件的设计与实现

    Institute of Scientific and Technical Information of China (English)

    罗许练

    2012-01-01

    PC-board network card on the MAC address of burn,the burn must be guaranteed with a global unique MAC address.Before burning the MAC address to a computer motherboard,need to compare the MAC address will burn and the MAC address database of the server.Whether the comparison protocol document is excellent or inferior,will directly determine the global uniqueness of the MAC address burn to the computer motherboard.%对电脑主板集成网卡进行MAC地址烧录时,必须保证烧录的MAC地址具有全球唯一性。MAC地址烧录到电脑主板前,需对烧录的MAC地址与服务器上的MAC地址库进行比对。比对协议文件的优劣,将直接决定烧录到电脑主板中的MAC地址的全球唯一性。

  4. Lightweight MAC-Spoof Detection Exploiting Received Signal Power and Median Filtering

    DEFF Research Database (Denmark)

    Papini, Davide

    2011-01-01

    IEEE 802.11 networks are subject to MAC-spoof attacks. An attacker can easily steal the identity of a legitimate station, even Access Points, thus enabling him to take full control over network basic mech- anisms or even access restricted resources. In this paper we propose a method to detect...

  5. Hyperresolving phase-only filters with an optically addressable liquid crystal spatial light modulator.

    Science.gov (United States)

    McOrist, J; Sharma, M D; Sheppard, C J R; West, E; Matsuda, K

    2003-01-01

    Hyperresolving (sometimes called 'superresolving' or 'ultraresolving') phase-only filters can be generated using an optically addressable liquid crystal spatial light modulator. This approach avoids the problems of low efficiency, and coupling between amplitude and phase modulation, that arise when using conventional liquid crystal modulators. When addressed by a programmed light intensity distribution, it allows filters to be changed rapidly to modify the response of a system or permit the investigation of different filter designs. In this paper we present experimental hyperresolved images obtained using an optically addressable parallel-aligned nematic LCD with two zone Toraldo type phase-only filters. The images are compared with theoretical predictions.

  6. Automatically Binding Method of IP Address, MAC Address and Switch Port of Enterprise LAN%企业局域网IP地址和物理地址及交换机端口自动绑定的方法

    Institute of Scientific and Technical Information of China (English)

    安学民; 杨尉薇; 郝金花

    2015-01-01

    Since the workload of LAN IP address, MAC address, and switch port binding is heavy, it is proposed to use C# and Secure CRT combining with VBScript to realize the binding of the three parameters. Example analysis shows this method can greatly improve the efficiency of binding and reduce the workload of the personnel engaged in operation and maintenance.%针对局域网中IP地址和物理地址及交换机端口绑定工作量较大的问题,提出利用C#、SecureCRT结合VBScript的方法完成局域网中3者的自动绑定.实例表明,该方法极大地提高了绑定工作的效率,减轻了运维人员的工作量.

  7. Mac Bible

    CERN Document Server

    Spivey, Dwight

    2009-01-01

    This essential guide answers all your questions on using a Macintosh computer, whether you?re unpacking your very first Mac after switching from a PC or upgrading from an older Mac. You?ll walk through all pre-installed Mac applications, including using Mac OS X, browsing the Web using Safari, downloading music from the iTunes store, troubleshooting Mac-specific problems, organizing photos in iPhoto, organizing calendars in iCal, editing digital video in iMovie, and more.

  8. Attendance System Based on Android Phone MAC Address%基于Android手机MAC地址的签到系统∗

    Institute of Scientific and Technical Information of China (English)

    刘兴云; 杨火祥; 付晶晶; 刘梦辉; 鲁池梅

    2016-01-01

    针对如何快速有效方便签到,对基于 Android平台的 WLAN热点技术进行了研究,设计了一种基于手机 MAC地址签到系统。提出该系统的逻辑设计及各个模块的功能设计,分析了系统的优势,最后针对所设想的系统进行了编译、实现及验证。该设计对签到考勤管理具有一定的实用价值,低成本、高效率的特点使它具有广阔的市场前景。%In order to realize the rapid and effective signing in,an attendance system based on phone MAC address and the WLAN tech-nology of Android platform.The logic design and the function of each module are introduced,the advantages of the system are analyzed. Finally,the compilation,implementation and verification are achieved.The system has important application value for the attendance management,and the characteristics of the low cost and high efficiency make it has a broad market prospect.

  9. Volumetric Ultrasound Imaging with Row-Column Addressed 2-D Arrays Using Spatial Matched Filter Beamforming

    DEFF Research Database (Denmark)

    Bouzari, Hamed; Engholm, Mathias; Christiansen, Thomas Lehrmann;

    2015-01-01

    For 3-D ultrasound imaging with row-column addressed 2-D arrays, the two orthogonal 1-D transmit and receive arrays are both used for one-way focusing in the lateral and elevation directions separately and since they are not in the same plane, the two-way focusing is the same as one-way focusing....

  10. Comparison of ICM with TPF-LEP to Prevent MAC Spoof DoS Attack in Wireless Local Area Infrastructure Network

    Directory of Open Access Journals (Sweden)

    M. Durairaj

    2014-05-01

    Full Text Available A Comparison of Integrated Central Manager (ICM and Traffic Pattern Filtering with Letter Envelop Protocol (TPF-LEP is done. Denial of Service (DoS attack is a biggest peril in wireless local area infrastructure network. It makes the resources unavailable for intended users which transpired through spoofing legitimate Client/AP's Medium Access Control (MAC address. MAC address are easily caricatured by the adversary clients, subsequently they are not encrypted. Since, the adversary sends the management frame, which is unencrypted, to the victim using spoofed MAC address. This study compares the performance of Integrated Central Manager (ICM and Traffic Pattern Filtering with Letter Envelop Protocol (TPF-LEP and evaluated the result using NS2. The attack scenario is simulated and effectiveness of the solutions is validated after the instigation of solutions in the attack consequences. Throughput, Packet Delivery Ratio and Packet Loss are measured and taken to endorse the performance of ICM and TPF-LEP.

  11. Macs for dummies

    CERN Document Server

    Baig, Edward C

    2014-01-01

    Get the most out of your Mac with this comprehensive guide Macs For Dummies, 13th Edition is the ultimate guide to your Mac, fully updated to include information about the latest updates. The book walks you through troubleshooting, syncing mobile devices, integrating Windows, and more, so you can take advantage of everything Macs have to offer. Whether you're a new user, a recent convert, or you just want to get the most out of your Mac, this book puts all the information you need in one place. Discover what makes Macs superior computing machines. Learn the basics, from mastering the Dock and

  12. Windows for Intel Macs

    CERN Document Server

    Ogasawara, Todd

    2008-01-01

    Even the most devoted Mac OS X user may need to use Windows XP, or may just be curious about XP and its applications. This Short Cut is a concise guide for OS X users who need to quickly get comfortable and become productive with Windows XP basics on their Macs. It covers: Security Networking ApplicationsMac users can easily install and use Windows thanks to Boot Camp and Parallels Desktop for Mac. Boot Camp lets an Intel-based Mac install and boot Windows XP on its own hard drive partition. Parallels Desktop for Mac uses virtualization technology to run Windows XP (or other operating systems

  13. Enterprise Mac administrators guide

    CERN Document Server

    Smith, William

    2015-01-01

    IT departments everywhere will be integrating Macs and Mac OS X into their IT infrastructure and this book will tell them how to do it. It will serve as an authoritative, useful and frequently referenced book on Mac OS X administration.

  14. H-MAC: A Hybrid MAC Protocol for Wireless Sensor Networks

    CERN Document Server

    Mehta, S; 10.5121/ijcnc.2010.2208

    2010-01-01

    In this paper, we propose a hybrid medium access control protocol (H-MAC) for wireless sensor networks. It is based on the IEEE 802.11's power saving mechanism (PSM) and slotted aloha, and utilizes multiple slots dynamically to improve performance. Existing MAC protocols for sensor networks reduce energy consumptions by introducing variation in an active/sleep mechanism. But they may not provide energy efficiency in varying traffic conditions as well as they did not address Quality of Service (QoS) issues. H-MAC, the propose MAC protocol maintains energy efficiency as well as QoS issues like latency, throughput, and channel utilization. Our numerical results show that H-MAC has significant improvements in QoS parameters than the existing MAC protocols for sensor networks while consuming comparable amount of energy.

  15. MacBook All-in-One For Dummies

    CERN Document Server

    Chambers, Mark L

    2011-01-01

    Get comfortable and confident with your MacBook! Combining the fun-but-straightforward content of nine minibooks, this new edition of MacBook All-in-One For Dummies delivers helpful coverage of the rich features and essential tools you need to know to use the MacBook to its fullest potential. You'll learn an array of MacBook basics while veteran author Mark Chambers walks you through setting up your MacBook, running programs, finding files with Finder, searching with Spotlight, keeping track with Address Book, enjoying music with iTunes, creating cool multimedia projects with iLife, and more.

  16. Mac at Work

    CERN Document Server

    Sparks, David

    2011-01-01

    Bridge the gap between using a Mac at home and at the office. Now that you love your Mac at home, you want to use one at the office without missing a beat of productivity or professionalism. This unique guide shows you how.  You'll find best Mac business practices for handling word processing, spreadsheet and presentation creation, task and project management, and graphics. The book also explores topics such as hardware maintenance, how to synchronize with multiple computers, data backup, and communication with Windows networks.: Covers the nuts and bolts of using a Mac at work, including sync

  17. Enterprise Mac Security Mac OS X Snow Leopard Security

    CERN Document Server

    Edge, Stephen Charles; Hunter, Beau; Sullivan, Gene; LeBlanc, Dee-Ann

    2010-01-01

    A common misconception in the Mac community is that Mac's operating system is more secure than others. While this might be true in certain cases, security on the Mac is still a crucial issue. When sharing is enabled or remote control applications are installed, Mac OS X faces a variety of security threats. Enterprise Mac Security: Mac OS X Snow Leopard is a definitive, expert-driven update of the popular, slash-dotted first edition and was written in part as a companion to the SANS Institute course for Mac OS X. It contains detailed Mac OS X security information, and walkthroughs on securing s

  18. The MAC framework: redefining MAC protocols for wireless sensor networks

    NARCIS (Netherlands)

    Parker, T.; Halkes, G.; Bezemer, M.; Langendoen, K.

    2010-01-01

    Most current WSN MAC protocol implementations have multiple tasks to perform—deciding on correct timing, sending of packets, sending of acknowledgements, etc. However, as much of this is common to all MAC protocols, there is duplication of functionality, which leads to larger MAC protocol code size

  19. The MAC framework: redefining MAC protocols for wireless sensor networks

    NARCIS (Netherlands)

    Parker, T.; Halkes, G.; Bezemer, M.; Langendoen, K.

    2010-01-01

    Most current WSN MAC protocol implementations have multiple tasks to perform—deciding on correct timing, sending of packets, sending of acknowledgements, etc. However, as much of this is common to all MAC protocols, there is duplication of functionality, which leads to larger MAC protocol code size

  20. Recent results from MAC

    Energy Technology Data Exchange (ETDEWEB)

    MAC Collaboration

    1982-05-01

    Some preliminary results from the MAC detector at PEP are presented. These include measurements of the angular distribution of ..gamma gamma.., ..mu mu.. and tau tau final states, a determination of the tau lifetime, a measurement of R, and a presentation of the inclusive muon p/sub perpendicular/ distribution for hadronic events.

  1. Macs For Seniors For Dummies

    CERN Document Server

    Chambers, Mark L

    2012-01-01

    You're never too old to fall in love—with your Mac! You took a while, but you are now the proud owner of your first Mac computer. Macs For Seniors For Dummies is just for you. This friendly, accessible guide walks you through choosing a Mac and learning how to use it. You'll find yourself falling head over heels for your Mac in no time. Macs For Seniors For Dummies introduces you to all the basics that you need to know: turning the Mac on and getting connected; using the keyboard and mouse; working with files and folders; navigate around the Mac desktop and OS X Lion; setting up an Inter

  2. Directional Medium Access Control (MAC Protocols in Wireless Ad Hoc and Sensor Networks: A Survey

    Directory of Open Access Journals (Sweden)

    David Tung Chong Wong

    2015-06-01

    Full Text Available This survey paper presents the state-of-the-art directional medium access control (MAC protocols in wireless ad hoc and sensor networks (WAHSNs. The key benefits of directional antennas over omni-directional antennas are longer communication range, less multipath interference, more spatial reuse, more secure communications, higher throughput and reduced latency. However, directional antennas lead to single-/multi-channel directional hidden/exposed terminals, deafness and neighborhood, head-of-line blocking, and MAC-layer capture which need to be overcome. Addressing these problems and benefits for directional antennas to MAC protocols leads to many classes of directional MAC protocols in WAHSNs. These classes of directional MAC protocols presented in this survey paper include single-channel, multi-channel, cooperative and cognitive directional MACs. Single-channel directional MAC protocols can be classified as contention-based or non-contention-based or hybrid-based, while multi-channel directional MAC protocols commonly use a common control channel for control packets/tones and one or more data channels for directional data transmissions. Cooperative directional MAC protocols improve throughput in WAHSNs via directional multi-rate/single-relay/multiple-relay/two frequency channels/polarization, while cognitive directional MAC protocols leverage on conventional directional MAC protocols with new twists to address dynamic spectrum access. All of these directional MAC protocols are the pillars for the design of future directional MAC protocols in WAHSNs.

  3. iMac pocket genius

    CERN Document Server

    Hart-Davis, Guy

    2010-01-01

    If you want to get the very most out of your iMac, put this savvy Portable Genius guide to work. Want to make the most of the new Magic Mouse and the latest iLife apps? Set up a wireless network using your iMac's AirPort card? Watch television on your iMac, or show iMac videos and movies on your television? You'll find cool and useful Genius tips, full-color screenshots, and pages of easy-to-access shortcuts and tools that will save you time and let you enjoy your iMac to the max.

  4. Monolithic MACS micro resonators

    Science.gov (United States)

    Lehmann-Horn, J. A.; Jacquinot, J.-F.; Ginefri, J. C.; Bonhomme, C.; Sakellariou, D.

    2016-10-01

    Magic Angle Coil Spinning (MACS) aids improving the intrinsically low NMR sensitivity of heterogeneous microscopic samples. We report on the design and testing of a new type of monolithic 2D MACS resonators to overcome known limitations of conventional micro coils. The resonators' conductors were printed on dielectric substrate and tuned without utilizing lumped element capacitors. Self-resonance conditions have been computed by a hybrid FEM-MoM technique. Preliminary results reported here indicate robust mechanical stability, reduced eddy currents heating and negligible susceptibility effects. The gain in B1 /√{ P } is in agreement with the NMR sensitivity enhancement according to the principle of reciprocity. A sensitivity enhancement larger than 3 has been achieved in a monolithic micro resonator inside a standard 4 mm rotor at 500 MHz. These 2D resonators could offer higher performance micro-detection and ease of use of heterogeneous microscopic substances such as biomedical samples, microscopic specimens and thin film materials.

  5. Blind Cognitive MAC Protocols

    CERN Document Server

    Mehanna, Omar; Gamal, Hesham El

    2008-01-01

    We consider the design of cognitive Medium Access Control (MAC) protocols enabling an unlicensed (secondary) transmitter-receiver pair to communicate over the idle periods of a set of licensed channels, i.e., the primary network. The objective is to maximize data throughput while maintaining the synchronization between secondary users and avoiding interference with licensed (primary) users. No statistical information about the primary traffic is assumed to be available a-priori to the secondary user. We investigate two distinct sensing scenarios. In the first, the secondary transmitter is capable of sensing all the primary channels, whereas it senses one channel only in the second scenario. In both cases, we propose MAC protocols that efficiently learn the statistics of the primary traffic online. Our simulation results demonstrate that the proposed blind protocols asymptotically achieve the throughput obtained when prior knowledge of primary traffic statistics is available.

  6. MacBook for dummies

    CERN Document Server

    Chambers , Mark L

    2014-01-01

    Make friends with your MacBook the fun and easy way! Ultra-light, ultra-fast, and ultra-powerful, the MacBook is the coolest laptop in town, and longtime Mac guru Mark L. Chambers is just the guy to help you get to know your MacBook in no time. Take a closer look at the latest features, get the lowdown on OS X, unleash your creative forces with iLife, take care of business with the iWork applications, and sync it all with iCloud with the expert advice in this bestselling MacBook guide. Whether this is your first MacBook or your first laptop, period, you''ll learn to navigate the Mac desktop, c

  7. Macs For Dummies, Pocket Edition

    CERN Document Server

    Baig, Edward C

    2011-01-01

    The fun and easy way to make the most of your wonderful Mac. Simply Mac-nificent — all the cool things your Mac can do! This handy guide helps you figure out the nuts and bolts of your Mac. Navigate the Mac desktop, use the Safari Web browser to surf the Internet, e-mail photos to friends and family, create and print documents, rip audio CDs, and more. The fun begins right here!. Open the book and find: How to set up and configure your Mac; Tips for getting around on the Mac desktop; Steps for setting up an e-mail account and browsing the Internet; Details about the free programs that come wit

  8. iMac portable genius

    CERN Document Server

    Hart-Davis, Guy

    2010-01-01

    The most up-to-date coverage on the latest iMac advice, tools, and shortcuts Cool and useful tips, full-color screenshots, and savvy advice show you how to get the most out of your iMac. Fully updated to cover the iMac's latest features and capabilities, this guide is packed with indispensible information on iLife '09 and Mac OS X Snow Leopard, and shows you how to customize your iMac in a way that it will work best for you.Explores all the bells and whistles of the iMac, including the new Magic Mouse, iLife apps such as iPhoto and iMovie, and Mac OS X Snow LeopardShows yo

  9. A MAC Layer Based Defense Architecture for Reduction of Quality (RoQ) Attacks in Wireless LAN

    CERN Document Server

    Singh, Jatinder; Kaur, Lakhwinder

    2010-01-01

    Recently an alternative of DDoS attacks called shrew attacks or Reduction of Quality (RoQ) has been identified which is very much difficult to detect. The RoQ attacks can use source and destination IP address spoofing, and they do not have distinct periodicity, and may not filter the attack packets precisely. In this paper, we propose to design the MAC layer based defense architecture for RoQ attacks in Wireless LAN which includes the detection and response stages. The attackers are detected by checking the RTS CTS packets from the MAC layer and the corresponding attack flows are blocked or rejected. By our simulation results, we show that our proposed technique achieves reduces the attack throughput there by increasing the received bandwidth and reducing the packet loss of legitimate users.

  10. iMac for dummies

    CERN Document Server

    Chambers, Mark L

    2014-01-01

    Do it all with your iMac and this bestselling For Dummies guide! You're still a little giddy from finally scoring your new iMac, and you can't wait to get started. Even if you're already in love with your iMac, it helps to have a little guidance to really get the most out of this ultimate all-in-one computer. This updated edition of iMac For Dummies is the ideal way to learn the iMac fundamentals from setting up and personalizing your machine to importing files, making FaceTime video calls, surfing the web, using your favorite programs and apps, and everything in between. Trusted Mac guru Mark

  11. Learn Excel 2011 for Mac

    CERN Document Server

    Hart-Davis, Guy

    2011-01-01

    Microsoft Excel 2011 for Mac OS X is a powerful application, but many of its most impressive features can be difficult to find. Learn Excel 2011 for Mac by Guy Hart-Davis is a practical, hands-on approach to learning all of the details of Excel 2011 in order to get work done efficiently on Mac OS X. From using formulas and functions to creating databases, from analyzing data to automating tasks, you'll learn everything you need to know to put this powerful application to use for a variety of tasks. What you'll learn * The secrets of the Excel for Mac interface! * How to create effective workbo

  12. Ellen MacArthur

    Institute of Scientific and Technical Information of China (English)

    Teodora; Lazarova

    2006-01-01

    Just over a year since breaking the round theworld solo record on board her 75 foot trimaranB&O,Ellen MacArthur embarked on a newventure:the Asian Record Circuit 2006,incorpo-rating the ‘Tour Of China’,and bringing a differ-ent set of challenges into new territories.Wespoke to Ellen and her team during their recent(April)stopover in Oingdao.When did you start sailing and what inspiredyou(you grew up in Derbyshire,in the UK,quite far away from the water)?I was introduced to sailing by my Aunt Thea ona small sailing boat called Cabaret.We wentsailing along the east coast of EngLand andbefore I knew it,I was hooked on sailing.I wasso inspired that when I was at school,I saved

  13. Macs for seniors for dummies

    CERN Document Server

    Chambers, Mark L

    2009-01-01

    Over 50 and thinking about getting your first computer? A user-friendly Mac is a great choice, and Macs For Seniors For Dummies walks you through choosing one and learning to use it. You won't even need your grandchildren to help! Macs For Seniors For Dummies introduces you to all the basic things you may not have encountered before-how to use the keyboard and mouse, work with files and folders, navigate around the Mac OS X desktop, set up an Internet connection, and much more. You'll learn to:Choose the Mac that's right for you, set it up, run programs and manage files, and hook up a printerU

  14. iMac for dummies

    CERN Document Server

    Chambers, Mark L

    2012-01-01

    The bestselling guide to the ultimate all-in-one computer—now updated and revised throughout! If you're looking for speed, performance, and power, the iMac is the ultimate all-in-one computer. From its superior performance, powerful operating system, and amazing applications, the iMac is one awesome machine, and the fun, friendly, and approachable style of iMac For Dummies is an ideal way to get started with the basics. You'll learn the fundamentals of the iMac including setting up and customizing your iMac and the software that comes with it, importing files from your old computer, send

  15. Design of High Speed Architecture of Parallel MAC Based On Radix-2 MBA

    Directory of Open Access Journals (Sweden)

    Syed Anwar Ahmed,

    2014-05-01

    Full Text Available The multiplier and multiplier-and-accumulator (MAC are the essential elements of the digital signal processing such as filtering, convolution, transformations and Inner products. Parallel MAC is frequently used in digital signal processing and video/graphics applications. Fast multipliers are essential parts of digital signal processing systems. The speed of multiply operation is of great importance in digital signal processing as well as in the general purpose processors today, especially since the media processing took off. The MAC provides high speed multiplication and multiplication with accumulative addition. This paper presents a combined process of multiplication and accumulation based on radix-4 & radix-8 booth encodings. In this Paper, we investigate the method of implementing the Parallel MAC with the smallest possible delay. Enhancing the speed of operation of the parallel MAC is a major design issue. This has been achieved by developing a CLA adder for parallel MAC.

  16. Aeronautical Mobile Airport Communications System (AeroMACS)

    Science.gov (United States)

    Budinger, James M.; Hall, Edward

    2011-01-01

    To help increase the capacity and efficiency of the nation s airports, a secure wideband wireless communications system is proposed for use on the airport surface. This paper provides an overview of the research and development process for the Aeronautical Mobile Airport Communications System (AeroMACS). AeroMACS is based on a specific commercial profile of the Institute of Electrical and Electronics Engineers (IEEE) 802.16 standard known as Wireless Worldwide Interoperability for Microwave Access or WiMAX (WiMax Forum). The paper includes background on the need for global interoperability in air/ground data communications, describes potential AeroMACS applications, addresses allocated frequency spectrum constraints, summarizes the international standardization process, and provides findings and recommendations from the world s first AeroMACS prototype implemented in Cleveland, Ohio, USA.

  17. Gotcha! Macs lose their innocence

    CERN Multimedia

    Computer Security Team

    2012-01-01

    Still believe your Mac is secure because Microsoft PCs fall prey to viruses and worms but Macs don’t? Time to wake up! This year has seen the first major compromise of Macs worldwide*. How is yours doing?   The “Flashback” Trojan is affecting Apple’s own variant of Java and compromises Macs via so-called drive-by infections, i.e. when you visit an appropriately prepared (infected!) website - and this might not necessarily be a site with questionable contents, but could well be a popular, reputable one. Security Companies worldwide have been monitoring this particular Trojan for a while and have estimated that more than half a million Macs were compromised. Connected to a few central command and control servers, the compromised Macs were then supporting the malicious activity of the bad guys! Fortunately, the security companies have now been able to take over those command and control servers and stop their destructive drive. So, Mac users, face the f...

  18. Java and Mac OS X

    CERN Document Server

    Davis, T Gene

    2010-01-01

    Learn the guidelines of integrating Java with native Mac OS X applications with this Devloper Reference book. Java is used to create nearly every type of application that exists and is one of the most required skills of employers seeking computer programmers. Java code and its libraries can be integrated with Mac OS X features, and this book shows you how to do just that. You'll learn to write Java programs on OS X and you'll even discover how to integrate them with the Cocoa APIs.: Shows how Java programs can be integrated with any Mac OS X feature, such as NSView widgets or screen savers; Re

  19. Mac Programming for Absolute Beginners

    CERN Document Server

    Wang, Wallace

    2011-01-01

    Want to learn how to program on your Mac? Not sure where to begin? Best-selling author Wallace Wang will explain how to get started with Cocoa, Objective-C, and Xcode. Whether you are an experienced Windows coder moving to the Mac, or you are completely new to programming, you'll see how the basic design of a Mac OS X program works, how Objective-C differs from other languages you may have used, and how to use the Xcode development environment. Most importantly, you'll learn how to use elements of the Cocoa framework to create windows, store data, and respond to users in your own Mac programs.

  20. MacBook portable genius

    CERN Document Server

    Miser, Brad

    2008-01-01

    The Genius is in. You don't have to be a genius to use a MacBook. But if you want to get the very most out of yours, put this savvy Portable Genius guide to work. Want to connect your MacBook to other Macs? Use Expose to its fullest potential? Troubleshoot? You'll find cool and useful Genius tips, insider secrets, full-color screenshots, and pages of easy-to-access shortcuts and tools that will save you loads of time and make your MacBook IQ soar. Portable GENIUS Fun, hip, and straightforward, the new Portable Genius series gives forward-thinking Apple users useful informat

  1. Mac mini真体验

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    2005年,Mac mini首次登场,众所周知,苹果的模具更换的并不频繁,在外貌没有大幅改变的情况下,迄今为止,Mac mini实际上已经更新了7代。最新的Mac mini的工业设计实际上延续了2008年开始的Unibody一体成型铝合金机身设计与其他Mac在外观上保持了一致的元素。更小的Mac mini看起来更加性感诱人,那么,你需要它么?

  2. Fiverr MacGyver

    Science.gov (United States)

    Hut, Rolf; van de Giesen, Nick; Larson, Martha

    2014-05-01

    Crowdsourcing has become popular over the past years, also for scientific endeavors. There are many Citizen Science projects and crowdfunding platforms, such as Kickstarter, that are make helpful contributions to moving environmental science forward. An interesting underused source of useful crowd-derived contributions to research is the website Fiverr.com. On this platform, thousands of people, acting as small-scale freelance contractors, offer their skills in the form of services. The platform offers a chance for people to take a hobby, skill, or pastime and make it something more by reaching out to a wider audience and by receiving a payment in return for services. As is typical of other crowdsourcing platforms, the tasks are small and usually self contained. As the name Fiverr suggests, offers start at US5 to provide a particular service. Services offered range from graphic design, to messages sung or spoken with various styles or accents, to complete apps for Android or iPhone. Skill providers on the platform can accept a range of variation of definition in the tasks, some can be described in general terms, for others it is more appropriate to provide examples. Fiverr provides a central location for those offering skills and those needing services to find each other, it makes it possible to communicate and exchange files, to make payments, and it provides support for resolving disputes. In all cases, it is important to keep expectations aligned with the nature of the platform: quality can and will vary. Ultimately, the critical contribution of Fiverr is not to replace professional services or otherwise save money, but rather to provide access to a large group of people with specialized skills who are able to make a contribution on short notice. In the context of this session, it can be considered a pool of people with MacGyver skills lying in wait of a MacGyyer task to attack. There are many ways in which Fiverr tasks, which are called 'gigs', can be useful in

  3. MacBook Teach Yourself VISUALLY

    CERN Document Server

    Miser, Brad

    2010-01-01

    Like the MacBook itself, Teach Yourself VISUALLY MacBook, Second Edition is designed to be visually appealing, while providing excellent functionality at the same time. By using this book, MacBook users will be empowered to do everyday tasks quickly and easily. From such basic steps as powering on or shutting down the MacBook, working on the Mac desktop with the Dashboard and its widgets to running Windows applications, Teach Yourself VISUALLY MacBook, Second Edition covers all the vital information and provides the help and support a reader needs—in many ways it's like having a Mac Genius at

  4. Switching to a Mac portable genius

    CERN Document Server

    McFedries, Paul

    2011-01-01

    Switching from a PC to a Mac is a breeze with this book Anyone considering making the move to Mac from the Windows world will find this book smoothes the way. While Macs are famous for ease of use, there are fundamental differences in Mac and PC ways of thinking, plus there?s the hassle of moving files, calendars, and other essential data from one platform to another. This guide lays out all the information, explains basic Mac procedures for the newcomer, offers great tips on data-sharing (including running Windows applications on a Mac), and provides everything the new Mac user needs to move

  5. Switching to a Mac For Dummies

    CERN Document Server

    Reinhold, Arnold

    2011-01-01

    Learn how to make the switch from PC to Mac a completely smooth transition The number of Mac users continues to increase significantly each year. If you are one of those people and are eager but also anxious about making the switch, then fear not! This friendly guide skips the jargon to deliver you an easy-to-read, understandable introduction to the Macintosh computer. Computer guru Arnold Reinhold walks you through the Mac OS, user interface, and icons. You'll learn how to set up your Mac, move your files from your PC to your Mac, switch applications, get your Mac online, network your Mac, se

  6. Recent advancements of wide-angle polarization analysis with 3He neutron spin filters

    Science.gov (United States)

    Chen, W. C.; Gentile, T. R.; Ye, Q.; Kirchhoff, A.; Watson, S. M.; Rodriguez-Rivera, J. A.; Qiu, Y.; Broholm, C.

    2016-09-01

    Wide-angle polarization analysis with polarized 3He based neutron spin filters (NSFs) has recently been employed on the Multi-Axis Crystal Spectrometer (MACS) at the National Institute of Standards and Technology Center for Neutron Research (NCNR). Over the past several years, the apparatus has undergone many upgrades to address the fundamental requirements for wide angle polarization analysis using spin exchange optical pumping based 3He NSFs. In this paper, we report substantial improvements in the on-beam-line performance of the apparatus and progress toward routine user capability. We discuss new standard samples used for 3He NSF characterization and the flipping ratio measurement on MACS. We further discuss the management of stray magnetic fields produced by operation of superconducting magnets on the MACS instrument, which can significantly reduce the 3He polarization relaxation time. Finally, we present the results of recent development of horseshoe-shaped wide angle cells.

  7. 78 FR 26711 - Federal Agricultural Mortgage Corporation Funding and Fiscal Affairs; Farmer Mac Liquidity...

    Science.gov (United States)

    2013-05-08

    ...; Farmer Mac Liquidity Management ACTION: Proposed rule; reopening of comment period. SUMMARY: The Farm... amend its liquidity management regulations for the Federal Agricultural Mortgage Corporation (Farmer Mac... liquidity by addressing four definitions in Sec. 652.5,\\3\\ liquidity management in Sec. 652.35, and the...

  8. Self-Admitted Pretensions of Mac Users on a Predominantly PC University Campus

    Science.gov (United States)

    Firmin, Michael W.; Wood, Whitney L. Muhlenkamp; Firmin, Ruth L.; Wood, Jordan C.

    2010-01-01

    The present qualitative research study addressed the overall research question of college students' pretention dynamics in the context of a university setting. Thirty-five Mac users were interviewed on a university campus that exclusively supports PC machines. Mac users shared four self-admitted pretensions related to using Macintosh computers.…

  9. Self-Admitted Pretensions of Mac Users on a Predominantly PC University Campus

    Science.gov (United States)

    Firmin, Michael W.; Wood, Whitney L. Muhlenkamp; Firmin, Ruth L.; Wood, Jordan C.

    2010-01-01

    The present qualitative research study addressed the overall research question of college students' pretention dynamics in the context of a university setting. Thirty-five Mac users were interviewed on a university campus that exclusively supports PC machines. Mac users shared four self-admitted pretensions related to using Macintosh computers.…

  10. MAC Support for High Density Wireless Sensor Networks

    NARCIS (Netherlands)

    Taddia, C.; Meratnia, Nirvana; van Hoesel, L.F.W.; Mazzini, G.; Havinga, Paul J.M.

    Large scale and high density networks of tiny sensor nodes offer promising solutions for event detection and actuating applications. In this paper we address the effect of high density of wireless sensor network performance with a specific MAC protocol, the Lightweight Medium Access Control (LMAC).

  11. Mac OS X Lion在Mac App Store上线

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    2011年7月20日,Apple宣布具有超过250种新功能的世界最先进操作系统的第八个重要版本Mac OS X Lion今天在Mac App StoreTM推出并可进行下载,价格为29.99美元。Lion的诸多超强功能包括:全新Multi-Touch手势;全系统支持全屏应用程序;

  12. Office 2011 for Mac For Dummies

    CERN Document Server

    LeVitus, Bob

    2011-01-01

    Get started with Office 2011 for Mac and discover the creative possibilitiesThe leading suite of productivity software for the Mac, Microsoft Office helps users complete common business tasks, including word processing, e-mail, presentations, financial analysis, and much more. Office 2011 for Mac For Dummies is the perfect companion for Microsoft Office for Mac users upgrading to the newest version, new computer users, and those who may have switched from the Windows version of Office. Written by one of the most popular gurus in the Mac community, Bob "Dr. Mac" LeVitus, the book explains every

  13. SACRB-MAC: A High-Capacity MAC Protocol for Cognitive Radio Sensor Networks in Smart Grid.

    Science.gov (United States)

    Yang, Zhutian; Shi, Zhenguo; Jin, Chunlin

    2016-03-31

    The Cognitive Radio Sensor Network (CRSN) is considered as a viable solution to enhance various aspects of the electric power grid and to realize a smart grid. However, several challenges for CRSNs are generated due to the harsh wireless environment in a smart grid. As a result, throughput and reliability become critical issues. On the other hand, the spectrum aggregation technique is expected to play an important role in CRSNs in a smart grid. By using spectrum aggregation, the throughput of CRSNs can be improved efficiently, so as to address the unique challenges of CRSNs in a smart grid. In this regard, we proposed Spectrum Aggregation Cognitive Receiver-Based MAC (SACRB-MAC), which employs the spectrum aggregation technique to improve the throughput performance of CRSNs in a smart grid. Moreover, SACRB-MAC is a receiver-based MAC protocol, which can provide a good reliability performance. Analytical and simulation results demonstrate that SACRB-MAC is a promising solution for CRSNs in a smart grid.

  14. SACRB-MAC: A High-Capacity MAC Protocol for Cognitive Radio Sensor Networks in Smart Grid

    Directory of Open Access Journals (Sweden)

    Zhutian Yang

    2016-03-01

    Full Text Available The Cognitive Radio Sensor Network (CRSN is considered as a viable solution to enhance various aspects of the electric power grid and to realize a smart grid. However, several challenges for CRSNs are generated due to the harsh wireless environment in a smart grid. As a result, throughput and reliability become critical issues. On the other hand, the spectrum aggregation technique is expected to play an important role in CRSNs in a smart grid. By using spectrum aggregation, the throughput of CRSNs can be improved efficiently, so as to address the unique challenges of CRSNs in a smart grid. In this regard, we proposed Spectrum Aggregation Cognitive Receiver-Based MAC (SACRB-MAC, which employs the spectrum aggregation technique to improve the throughput performance of CRSNs in a smart grid. Moreover, SACRB-MAC is a receiver-based MAC protocol, which can provide a good reliability performance. Analytical and simulation results demonstrate that SACRB-MAC is a promising solution for CRSNs in a smart grid.

  15. Mac OS X Lion Server For Dummies

    CERN Document Server

    Rizzo, John

    2011-01-01

    The perfect guide to help administrators set up Apple's Mac OS X Lion Server With the overwhelming popularity of the iPhone and iPad, more Macs are appearing in corporate settings. The newest version of Mac Server is the ideal way to administer a Mac network. This friendly guide explains to both Windows and Mac administrators how to set up and configure the server, including services such as iCal Server, Podcast Producer, Wiki Server, Spotlight Server, iChat Server, File Sharing, Mail Services, and support for iPhone and iPad. It explains how to secure, administer, and troubleshoot the networ

  16. Take Control of Maintaining Your Mac

    CERN Document Server

    Kissell, Joe

    2009-01-01

    Keep your Mac running smoothly with our easy maintenance program! Regular maintenance is necessary to avoid problems and to ensure your Mac runs at peak performance, but it's hard to know what to do and when to do it. Best-selling author Joe Kissell has now applied his commonsense approach to the task of maintaining your Mac, whether you use Tiger or Leopard! Learn how to start on the right foot; what you should do daily, weekly, monthly, and yearly; and how to prepare for Mac OS X updates. Joe even explains how to monitor your Mac's health and debunks common panaceas. Read this book to lea

  17. Switching to a Mac For Dummies

    CERN Document Server

    Reinhold, Arnold

    2007-01-01

    Thinking of making the switch from your PC to a Mac? Congratulations! You're in for a great, virus-free ride. And Switching to Mac For Dummies makes it smoother than you ever imagined. From buying the Mac that's right for you to transferring your files to breaking your old Windows habits and learning to do things the (much easier) Mac way, it makes the whole process practically effortless. Whether you've been using Windows XP, Vista, or even Linux, you'll find simple, straightforward ways to make your transition go smoothly. That will leave you plenty of time to get familiar with Mac'

  18. Switching to the Mac The Missing Manual

    CERN Document Server

    Pogue, David

    2010-01-01

    Is Windows giving you pause? Ready to make the leap to the Mac instead? There has never been a better time to switch from Windows to Mac, and this incomparable guide will help you make a smooth transition. New York Times columnist and Missing Manuals creator David Pogue gets you past three challenges: transferring your stuff, assembling Mac programs so you can do what you did with Windows, and learning your way around Mac OS X. Learning to use a Mac is not a piece of cake, but once you do, the rewards are oh-so-much better. No viruses, worms, or spyware. No questionable firewalls, inefficien

  19. Cognitive MAC designs for OSA networks

    CERN Document Server

    Derakhshani, Mahsa

    2014-01-01

    This SpringerBrief presents recent advances in the cognitive MAC designs for opportunistic spectrum access (OSA) networks. It covers the basic MAC functionalities and MAC enhancements of IEEE 802.11. Later chapters discuss the existing MAC protocols for OSA and classify them based on characteristic features. The authors provide new research in adaptive carrier sensing-based MAC designs tailored for OSA, which optimize spectrum utilization and ensure a peaceful coexistence of licensed and unlicensed systems. Analytically devised via optimization and game-theoretic approaches, these adaptive M

  20. MQ-MAC: A Multi-Constrained QoS-Aware Duty Cycle MAC for Heterogeneous Traffic in Wireless Sensor Networks

    Science.gov (United States)

    Monowar, Muhammad Mostafa; Rahman, Md. Obaidur; Hong, Choong Seon; Lee, Sungwon

    2010-01-01

    Energy conservation is one of the striking research issues now-a-days for power constrained wireless sensor networks (WSNs) and hence, several duty-cycle based MAC protocols have been devised for WSNs in the last few years. However, assimilation of diverse applications with different QoS requirements (i.e., delay and reliability) within the same network also necessitates in devising a generic duty-cycle based MAC protocol that can achieve both the delay and reliability guarantee, termed as multi-constrained QoS, while preserving the energy efficiency. To address this, in this paper, we propose a Multi-constrained QoS-aware duty-cycle MAC for heterogeneous traffic in WSNs (MQ-MAC). MQ-MAC classifies the traffic based on their multi-constrained QoS demands. Through extensive simulation using ns-2 we evaluate the performance of MQ-MAC. MQ-MAC provides the desired delay and reliability guarantee according to the nature of the traffic classes as well as achieves energy efficiency. PMID:22163439

  1. MQ-MAC: a multi-constrained QoS-aware duty cycle MAC for heterogeneous traffic in wireless sensor networks.

    Science.gov (United States)

    Monowar, Muhammad Mostafa; Rahman, Md Obaidur; Hong, Choong Seon; Lee, Sungwon

    2010-01-01

    Energy conservation is one of the striking research issues now-a-days for power constrained wireless sensor networks (WSNs) and hence, several duty-cycle based MAC protocols have been devised for WSNs in the last few years. However, assimilation of diverse applications with different QoS requirements (i.e., delay and reliability) within the same network also necessitates in devising a generic duty-cycle based MAC protocol that can achieve both the delay and reliability guarantee, termed as multi-constrained QoS, while preserving the energy efficiency. To address this, in this paper, we propose a Multi-constrained QoS-aware duty-cycle MAC for heterogeneous traffic in WSNs (MQ-MAC). MQ-MAC classifies the traffic based on their multi-constrained QoS demands. Through extensive simulation using ns-2 we evaluate the performance of MQ-MAC. MQ-MAC provides the desired delay and reliability guarantee according to the nature of the traffic classes as well as achieves energy efficiency.

  2. MQ-MAC: A Multi-Constrained QoS-Aware Duty Cycle MAC for Heterogeneous Traffic in Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Sungwon Lee

    2010-11-01

    Full Text Available Energy conservation is one of the striking research issues now-a-days for power constrained wireless sensor networks (WSNs and hence, several duty-cycle based MAC protocols have been devised for WSNs in the last few years. However, assimilation of diverse applications with different QoS requirements (i.e., delay and reliability within the same network also necessitates in devising a generic duty-cycle based MAC protocol that can achieve both the delay and reliability guarantee, termed as multi-constrained QoS, while preserving the energy efficiency. To address this, in this paper, we propose a Multi-constrained QoS-aware duty-cycle MAC for heterogeneous traffic in WSNs (MQ-MAC. MQ-MAC classifies the traffic based on their multi-constrained QoS demands. Through extensive simulation using ns-2 we evaluate the performance of MQ-MAC. MQ-MAC provides the desired delay and reliability guarantee according to the nature of the traffic classes as well as achieves energy efficiency.

  3. Mac OS X Tiger for Unix Geeks

    CERN Document Server

    Jepson, Brian

    2005-01-01

    If you're one of the many Unix developers drawn to Mac OS X for its Unix core, you'll find yourself in surprisingly unfamiliar territory. Unix and Mac OS X are kissing cousins, but there are enough pitfalls and minefields in going from one to another that even a Unix guru can stumble, and most guides to Mac OS X are written for Mac aficionados. For a Unix developer, approaching Tiger from the Mac side is a bit like learning Russian by reading the Russian side of a Russian-English dictionary. Fortunately, O'Reilly has been the Unix authority for over 25 years, and in Mac OS X Tiger for Unix Gee

  4. Teach yourself visually Mac Mini

    CERN Document Server

    Hart-Davis, Guy

    2012-01-01

    The perfect how-to guide for visual learners Apple?s Mac Mini packs a powerful punch is in a small package, including both HDMI and Thunderbolt ports plus the acclaimed OS X. But if you want to get the very most from all this power and versatility, be sure to get this practical visual guide. With full-color, step-by-step instructions as well as screenshots and illustrations on every page, it clearly shows you how to accomplish tasks rather than burying you in pages of text. Discover helpful visuals and how-tos on the OS, hardware specs, Launchpad, the App Store, multimedia capabilities (such

  5. Web Development with the Mac

    CERN Document Server

    Vegh, Aaron

    2010-01-01

    Learn Web development the Apple way and build a business. With a focus on both coding and creative development, this in-depth guide thoroughly covers what you need to know to build winning websites for clients — from what it takes to bring a business online to how to make your site interactive to how to run a freelance web business. In between, you'll master the technical tools of the trade — such as HTML, CSS, JavaScript, PHP, and Ruby on Rails — and learn how to create beautiful interfaces using Photoshop . This book covers everything a fledgling web developer working on a Mac needs to launc

  6. Anonymous-address-resolution model

    Institute of Scientific and Technical Information of China (English)

    Guang-jia SONG; Zhen-zhou JI

    2016-01-01

    Address-resolution protocol (ARP) is an important protocol of data link layers that aims to obtain the corresponding relationship between Internet Protocol (IP) and Media Access Control (MAC) addresses. Traditional ARPs (address-resolution and neighbor-discovery protocols) do not consider the existence of malicious nodes, which reveals destination addresses in the resolution process. Thus, these traditional protocols allow malicious nodes to easily carry out attacks, such as man-in-the-middle attack and denial-of-service attack. To overcome these weaknesses, we propose an anonymous-address-resolution (AS-AR) protocol. AS-AR does not publicize the destination address in the address-resolution process and hides the IP and MAC addresses of the source node. The malicious node cannot obtain the addresses of the destination and the node which initiates the address resolution; thus, it cannot attack. Analyses and experiments show that AS-AR has a higher security level than existing security methods, such as secure-neighbor discovery.

  7. Analysis of 3gpp-MAC and two-key 3gpp-MAC

    DEFF Research Database (Denmark)

    Knudsen, Lars Ramkilde; Mitchell, C.J.

    2003-01-01

    Forgery and key-recovery attacks are described on the 3gpp-MAC scheme, proposed for inclusion in the 3gpp specification. Three main classes of attack are given, all of which operate whether or not truncation is applied to the MAC value. Attacks in the first class use a large number of 'chosen MACs......', those in the second class use a large number of 'known MACs', and those in the third class require a large number of MAC verifications, but very few known MACS and no chosen MACS. The first class yields both forgery and key-recovery attacks, whereas the second and third classes are key-recovery attacks...... only. Both single-key and two-key variants of 3gpp-MAC are considered; the forgery attacks are relevant to both variants, whereas the key-recovery attacks are only relevant to the two-key variant....

  8. Analysis of 3gpp-MAC and two-key 3gpp-MAC

    DEFF Research Database (Denmark)

    Knudsen, Lars Ramkilde; Mitchell, C.J.

    2003-01-01

    Forgery and key-recovery attacks are described on the 3gpp-MAC scheme, proposed for inclusion in the 3gpp specification. Three main classes of attack are given, all of which operate whether or not truncation is applied to the MAC value. Attacks in the first class use a large number of 'chosen MACs......', those in the second class use a large number of 'known MACs', and those in the third class require a large number of MAC verifications, but very few known MACS and no chosen MACS. The first class yields both forgery and key-recovery attacks, whereas the second and third classes are key-recovery attacks...... only. Both single-key and two-key variants of 3gpp-MAC are considered; the forgery attacks are relevant to both variants, whereas the key-recovery attacks are only relevant to the two-key variant....

  9. Mac protocols for cyber-physical systems

    CERN Document Server

    Xia, Feng

    2015-01-01

    This book provides a literature review of various wireless MAC protocols and techniques for achieving real-time and reliable communications in the context of cyber-physical systems (CPS). The evaluation analysis of IEEE 802.15.4 for CPS therein will give insights into configuration and optimization of critical design parameters of MAC protocols. In addition, this book also presents the design and evaluation of an adaptive MAC protocol for medical CPS, which exemplifies how to facilitate real-time and reliable communications in CPS by exploiting IEEE 802.15.4 based MAC protocols. This book wil

  10. Take control of troubleshooting your Mac

    CERN Document Server

    Kissell, Joe

    2009-01-01

    Learn how to solve any Mac problem with Joe Kissell's expert advice! We may love our Macs, but they can still suffer significant problems. In this essential guide from best-selling author Joe Kissell, you'll learn 17 basic troubleshooting procedures and how to solve 9 common problems, along with an easy-to-follow way to troubleshoot novel problems. Whether your Mac won't turn on, experiences kernel panics repeatedly, or is glacially slow, this book has the calm, friendly advice you need to find a solution. Following in the footsteps of his critically acclaimed books Take Control of Mac OS X

  11. Teach yourself visually MacBook Pro

    CERN Document Server

    Hart-Davis, Guy

    2014-01-01

    Clear instructions to help visual learners get started with their MacBook Pro Covering all the essential information you need to get up to speed with your MacBook Pro, this new edition provides you with the most up-to-date information on performing everyday tasks quickly and easily. From basics such as powering on or shutting down the MacBook Pro to more advanced tasks such as running Windows applications, this visual guide provides the help and support you need to confidently use your MacBook Pro to its full potential.Empowers you to perform everyday tasks quickly and easilyCovers new hardwa

  12. Take control the Mac OS X lexicon

    CERN Document Server

    Zardetto, Sharon

    2009-01-01

    This ebook explains a little bit of everything; in fact, it's The Mac OS X (and then some) Lexicon because it's never just you and your Mac. It's you and your Mac and the Web, and your email, and that article you just read that threw 17 new acronyms at you or assumed that you knew all sorts of networking terms. Or it's you and your Mac and Finder features you've never touched, such as burn folders, smart folders, or proxy icons, and that mysterious Services submenu. This book is a great guide for Macintosh users everywhere who have trouble keeping up with the latest jargon, fo

  13. Macs all-in-one for dummies

    CERN Document Server

    Hutsko, Joe

    2014-01-01

    Your all-in-one guide to unleashing your Mac's full potential It's a Mac world out there. But if you haven't read the instruction manual, you may be neglecting some of your computer's coolest features. Turn to Macs All-in-One For Dummies' jam-packed guide to access the incredible tools within your computer. With this fully updated reference, you will learn how to use Launchpad and Mission Control; protect your Mac; back up and restore data with Time Machine; sync across devices in iCloud; import, organize, and share photos; direct in iMovie; compose in GarageBand; and so much more. The possi

  14. Quicksilver Power Mac G4

    CERN Multimedia

    2001-01-01

    A new generation with a reworked motherboard is launched on 2001 with however the same Graphite box. It also included a processor speed-bump, and brought the DVD-R "SuperDrive" to the mid-level model. The Quicksilver PowerMac was available in three configurations: The 733 MHz model, with 128 MB of RAM, a 40 GB hard drive, and a CD-RW drive, was 1,699 dollars, the 867 MHz configuration, with 128 MB of RAM, a 60 GB hard drive and a DVD-R drive, was 2,499 dollars, and the high-end dual-800 MHz model, with 256 MB of RAM, an 80 GB hard drive and a DVD-R drive, was 3,499 dollars. The 733 MHz model is the first personal computer to have a DVD burner, named SuperDrive at Apple. The design was updated on 2002 with 800 MHz, 933 MHz and dual 1 GHz configurations, becoming the first Mac to reach 1 GHz.

  15. Wound healing in Mac-1 deficient mice.

    Science.gov (United States)

    Chen, Lin; Nagaraja, Sridevi; Zhou, Jian; Zhao, Yan; Fine, David; Mitrophanov, Alexander Y; Reifman, Jaques; DiPietro, Luisa A

    2017-05-01

    Mac-1 (CD11b/CD18) is a macrophage receptor that plays several critical roles in macrophage recruitment and activation. Because macrophages are essential for proper wound healing, the impact of Mac-1 deficiency on wound healing is of significant interest. Prior studies have shown that Mac-1(-/-) mice exhibit deficits in healing, including delayed wound closure in scalp and ear wounds. This study examined whether Mac-1 deficiency influences wound healing in small excisional and incisional skin wounds. Three millimeter diameter full thickness excisional wounds and incisional wounds were prepared on the dorsal skin of Mac-1 deficient (Mac-1(-/-) ) and wild type (WT) mice, and wound healing outcomes were examined. Mac-1 deficient mice exhibited a normal rate of wound closure, generally normal levels of total collagen, and nearly normal synthesis and distribution of collagens I and III. In incisional wounds, wound breaking strength was similar for Mac-1(-/-) and WT mice. Wounds of Mac-1 deficient mice displayed normal total macrophage content, although macrophage phenotype markers were skewed as compared to WT. Interestingly, amounts of TGF-β1 and its downstream signaling molecules, SMAD2 and SMAD3, were significantly decreased in the wounds of Mac-1 deficient mice compared to WT. The results suggest that Mac-1 deficiency has little impact on the healing of small excisional and incisional wounds. Moreover, the findings demonstrate that the effect of single genetic deficiencies on wound healing may markedly differ among wound models. These conclusions have implications for the interpretation of the many prior studies that utilize a single model system to examine wound healing outcomes in genetically deficient mice. © 2017 by the Wound Healing Society.

  16. A MAC Mode for Lightweight Block Ciphers

    DEFF Research Database (Denmark)

    Luykx, Atul; Preneel, Bart; Tischhauser, Elmar Wolfgang;

    2016-01-01

    , but also allows high-performance parallel implementations. We highlight this in a comprehensive implementation study, instantiating LightMAC with PRESENT and the AES. Moreover, LightMAC allows flexible trade-offs between rate and maximum message length. Unlike PMAC and its many derivatives, Light...

  17. MAC-awake of sevoflurane in children.

    Science.gov (United States)

    Davidson, Andrew J; Wong, Aaron; Knottenbelt, Graham; Sheppard, Suzette; Donath, Susan; Frawley, Geoff

    2008-08-01

    Age influences the potency of anesthetic agents, but there is little information on how age influences MAC-awake. MAC-awake may be an important aspect of anesthesia potency for the prevention of awareness during anesthesia. The aim of this study was to measure MAC-awake in a range of ages in children. After institutional ethics approval and informed parental consent 60 children were enrolled; 20 in each of three age groups (2 to awake. The Dixon up-down method was used to determine progression of subsequent concentrations and MAC-awake (ED50) for the three age groups were obtained using the probit model. This study found evidence for a difference in ED50 between age groups (P = 0.008). The MAC-awake was highest in the youngest group (0.66%) and similar in the older groups (0.45% and 0.43%). Although MAC-awake changes with age, in the ages where awareness has been reported, MAC-awake was found to be relatively low, and therefore it seems unlikely that age-specific changes to MAC-awake are a cause for awareness in children aged 5-12 years.

  18. Nomogram to estimate age-related MAC.

    NARCIS (Netherlands)

    Lerou, J.G.C.

    2004-01-01

    BACKGROUND: In clinical practice it is difficult to estimate rapidly two important values: (i) the total age-corrected MAC multiple from measured end-expired concentrations of volatile agent and nitrous oxide; (ii) the end-expired concentration of volatile agent needed to obtain a given total MAC

  19. VLA-MAC: A Variable Load Adaptive MAC Protocol for Wireless Sensor Networks

    Science.gov (United States)

    Yao, Guoliang; Liu, Hao; Chen, Hao; Shi, Longxin

    This letter presents VLA-MAC, a novel adaptive MAC protocol for wireless sensor networks that can achieve high energy efficiency and low latency in variable load conditions. In VLA-MAC, traffic load is measured online and utilized for adaptive adjustment. VLA-MAC transmits packets via a burst style to alleviate packets accumulation problem and achieve low latency in high load condition. Furthermore, it also saves obvious energy by removing unnecessary listen period in low load condition. Unlike current approach, VLA-MAC does not need to adjust duty-cycle according to load online. Simulation results based on ns-2 show the performance improvements of our protocol.

  20. Mac OS X Snow Leopard for dummies

    CERN Document Server

    LeVitus, Bob

    2010-01-01

    Get to know Snow Leopard and make the most of your Mac Snow Leopard has a few new tricks up its sleeve, so whether you're new to Mac or a longtime Mac-thusiast, Mac expert Bob LeVitus has tips you'll appreciate. Learn how to start up your Mac, get to know the Dock and Finder, work your way through windows and dialogs, and organize and manage files and folders. Open the book and find: How to navigate around the Finder, Dock, and desktop Tips for opening, closing, resizing, and moving windows Steps for keeping Snow Leopard organized How to back up your system with Time Machine® Troubleshooting a

  1. Adaptive low-power listening MAC protocol based on transmission rates.

    Science.gov (United States)

    Hwang, Kwang-il; Yi, Gangman

    2014-01-01

    Even though existing low-power listening (LPL) protocols have enabled ultra-low-power operation in wireless sensor networks (WSN), they do not address trade-off between energy and delay, since they focused only on energy aspect. However, in recent years, a growing interest in various WSN applications is requiring new design factors, such as minimum delay and higher reliability, as well as energy efficiency. Therefore, in this paper we propose a novel sensor multiple access control (MAC) protocol, transmission rate based adaptive low-power listening MAC protocol (TRA-MAC), which is a kind of preamble-based LPL but is capable of controlling preamble sensing cycle adaptively to transmission rates. Through experiments, it is demonstrated that TRA-MAC enables LPL cycle (LC) and preamble transmission length to adapt dynamically to varying transmission rates, compensating trade-off between energy and response time.

  2. MacMath 92 a dynamical systems software package for the Macintosh

    CERN Document Server

    Hubbard, John H

    1993-01-01

    MacMath is a scientific toolkit for the Macintosh computer consisting of twelve graphics programs. It supports mathematical computation and experimentation in dynamical systems, both for differential equations and for iteration. The MacMath package was designed to accompany the textbooks Differential Equations: A Dynamical Systems Approach Part I & II. The text and software was developed for a junior-senior level course in applicable mathematics at Cornell University, in order to take advantage of excellent and easily accessible graphics. MacMath addresses differential equations and iteration such as: analyzer, diffeq, phase plane, diffeq 3D views, numerical methods, periodic differential equations, cascade, 2D iteration, eigenfinder, jacobidraw, fourier, planets. These versatile programs greatly enhance the understanding of the mathematics in these topics. Qualitative analysis of the picture leads to quantitative results and even to new mathematics. This new edition includes the latest version of the Mac...

  3. Comparison of CSMA based MAC protocols of wireless sensor networks

    CERN Document Server

    singh, Himanshu

    2012-01-01

    Energy conservation has been an important area of interest in Wireless Sensor networks (WSNs). Medium Access Control (MAC) protocols play an important role in energy conservation. In this paper, we describe CSMA based MAC protocols for WSN and analyze the simulation results of these protocols. We implemented S-MAC, T-MAC, B-MAC, B-MAC+, X-MAC, DMAC and Wise-MAC in TOSSIM, a simulator which unlike other simulators simulates the same code running on real hardware. Previous surveys mainly focused on the classification of MAC protocols according to the techniques being used or problem dealt with and presented a theoretical evaluation of protocols. This paper presents the comparative study of CSMA based protocols for WSNs, showing which MAC protocol is suitable in a particular environment and supports the arguments with the simulation results. The comparative study can be used to find the best suited MAC protocol for wireless sensor networks in different environments.

  4. Mac OS X for Unix Geeks (Leopard)

    CERN Document Server

    Rothman, Ernest E; Rosen, Rich

    2009-01-01

    If you've been lured to Mac OS X because of its Unix roots, this invaluable book serves as a bridge between Apple's Darwin OS and the more traditional Unix systems. The new edition offers a complete tour of Mac OS X's Unix shell for Leopard and Tiger, and helps you find the facilities that replace or correspond to standard Unix utilities. Learn how to compile code, link to libraries, and port Unix software to Mac OS X and much more with this concise guide.

  5. Mac OS X Lion portable genius

    CERN Document Server

    Spivey, Dwight

    2012-01-01

    Two e-books, Mac OS X Lion Portable Genius and MacBook Pro Portable Genius, Third Edition, bundled in one package Books in the Portable Genius series provide readers with the most accessible, useful information possible, including plenty of tips and techniques for the most-used features in a product or software. These e-books will show you what you may not find out by just working with your MacBook Pro and OS X Lion. Genius icons present smart or innovative ways to do something, saving time and hassle. Easy-to-find information gives you the essentials plus insightful tips on how to navigate

  6. Office 2008 for Mac for dummies

    CERN Document Server

    LeVitus, Bob

    2013-01-01

    Office 2008 for Mac is here, with great new enhancements to all your favorite office productivity tools. Who better than "Dr. Mac, "Bob LeVitus, to show you how to load and use them all? From choosing the best version for your needs to managing your life with your online calendar, Office 2008 For Mac For Dummies covers what you need to know. It compares the Student/Teacher Edition, Standard Edition, and Professional Edition, then walks you through installing your preferred version and keeping it up to date. You'll find out all the things you can do with Word, Excel, PowerPoint, and Entourage,

  7. Wireless sensors networks MAC protocols analysis

    CERN Document Server

    Chaari, Lamia

    2010-01-01

    Wireless sensors networks performance are strictly related to the medium access mechanism. An effective one, require non-conventional paradigms for protocol design due to several constraints. An adequate equilibrium between communication improvement and data processing capabilities must be accomplished. To achieve low power operation, several MAC protocols already proposed for WSN. The aim of this paper is to survey and to analyze the most energy efficient MAC protocol in order to categorize them and to compare their performances. Furthermore we have implemented some of WSN MAC protocol under OMNET++ with the purpose to evaluate their performances.

  8. Beginning Mac OS X Snow Leopard programming

    CERN Document Server

    Trent, Michael

    2010-01-01

    Michael Trent is a technical reviewer for numerous books and magazine articles and the coauthor of Beginning Mac OS X Programming with Drew McCormack. Drew McCormack is an experienced computational scientist, founder of the ""The Mental Faculty""-an independent company developing software for the Mac and iPhone-and the coauthor of Beginning Mac OS X Programming with Michael Trent. Wrox Beginning guides are crafted to make learning programming languages and technologies easier than you think, providing a structured, tutorial format that will guide you through all the techniques involved.

  9. Learn Office 2011 for Mac OS X

    CERN Document Server

    Hart-Davis, Guy

    2011-01-01

    Office for Mac remains the leading productivity suite for Mac, with Apple's iWork and the free OpenOffice.org trailing far behind. And now it's being updated with a cleaner interface and more compatibility with Exchange and SharePoint. Learn Office 2011 for Mac OS X offers a practical, hands-on approach to using Office 2011 applications to create and edit documents and get work done efficiently. You'll learn how to customize Office, design, create, and share documents, manipulate data in a spreadsheet, and create lively presentations. You'll also discover how to organize your email, contacts,

  10. 面向IP地址集过滤的高效包分类技术%Efficient packet classification technique for IP address set filtering

    Institute of Scientific and Technical Information of China (English)

    乔龙飞; 刘剑英; 郑建生

    2015-01-01

    Traditional network firewall uses a linear package matching algorithm which is very inefficient, and it”s also very difficult to manage complex rules and tables. To improve this, this paper designed and implemented a Netfilter extension framework called Salist ( simple address list) . Salist contains a table management module based on kernel virtual file system, a rule management module that can automatically merge and sort rules in tables and an efficient packet matching module based on Bsearch algorithm. The time complexity of the packet matching algorithm declines to O ( log n ) from O ( n ) . The kernel memory space to store the rules reduces by at lease 10 percent. The management of the rules is much easier because rules are stored in different files in kernel space. The results show that the Salist framework can substantially improve the network packet forwarding speed.%针对传统防火墙线性匹配算法匹配效率低、维护困难等问题,提出并实现了一种面向IP地址集过滤的高效、灵活的Netfilter扩展框架Salist。 Salist包含一个基于内核虚拟文件的表管理模块,一个可自动对IP地址集进行去重、归并和排序的表内规则管理模块,一个基于Bsearch算法的高效的包匹配模块。通过理论分析和实际测试证明, Salist使包匹配算法时间复杂度由传统线性匹配的O( n)降低为O( log n),规则合并减少了规则表占用的内核内存空间10%以上,按文件分离的规则管理机制简化了对规则集进行维护的难度。结果表明Salist使用在核心网络设备中可极大提高包转发速率,降低规则的内存占用和管理难度。

  11. MAC Layer Hurdles in BSNs

    CERN Document Server

    Ullah, Sana; Choi, Young-Woo; Lee, Hyung-Soo; Kwak, Kyung Sup

    2009-01-01

    The last few decades have seen considerable research progress in microelectronics and integrated circuits, system-on-chip design, wireless communication, and sensor technology. This progress has enabled the seamless integration of autonomous wireless sensor nodes around a human body to create a Body Sensor Network (BSN). The development of a proactive and ambulatory BSN induces a number of enormous issues and challenges. This paper presents the technical hurdles during the design and implementation of a low-power Medium Access Control (MAC) protocol for in-body and on-body sensor networks. We analyze the performance of IEEE 802.15.4 protocol for the on-body sensor network. We also provide a comprehensive insight into the heterogeneous characteristics of the in-body sensor network. A low-power technique called Pattern-Based Wake-up Table is proposed to handle the normal traffic in a BSN. The proposed technique provides a reliable solution towards low-power communication in the in-body sensor network.

  12. CR-MAC: A multichannel MAC protocol for cognitive radio ad hoc networks

    CERN Document Server

    Kamruzzaman, S M

    2010-01-01

    This paper proposes a cross-layer based cognitive radio multichannel medium access control (MAC) protocol with TDMA, which integrate the spectrum sensing at physical (PHY) layer and the packet scheduling at MAC layer, for the ad hoc wireless networks. The IEEE 802.11 standard allows for the use of multiple channels available at the PHY layer, but its MAC protocol is designed only for a single channel. A single channel MAC protocol does not work well in a multichannel environment, because of the multichannel hidden terminal problem. Our proposed protocol enables secondary users (SUs) to utilize multiple channels by switching channels dynamically, thus increasing network throughput. In our proposed protocol, each SU is equipped with only one spectrum agile transceiver, but solves the multichannel hidden terminal problem using temporal synchronization. The proposed cognitive radio MAC (CR-MAC) protocol allows SUs to identify and use the unused frequency spectrum in a way that constrains the level of interference...

  13. Learn Mac OS X Snow Leopard

    CERN Document Server

    Meyers, Scott

    2009-01-01

    You're smart and savvy, but also busy. This comprehensive guide to Apple's Mac OS X 10.6, Snow Leopard, gives you everything you need to know to live a happy, productive Mac life. Learn Mac OS X Snow Leopard will have you up and connected lickity split. With a minimum of overhead and a maximum of useful information, you'll cover a lot of ground in the time it takes other books to get you plugged in. If this isn't your first experience with Mac OS X, skip right to the "What's New in Snow Leopard" sections. You may also find yourself using this book as a quick refresher course or a way

  14. Macintosh Troubleshooting Pocket Guide for Mac OS

    CERN Document Server

    Lerner, David; Corporation, Tekserve

    2009-01-01

    The Macintosh Troubleshooting Pocket Guide covers the most common user hardware and software trouble. It's not just a book for Mac OS X (although it includes tips for OS X and Jaguar), it's for anyone who owns a Mac of any type-- there are software tips going back as far as OS 6. This slim guide distills the answers to the urgent questions that Tekserve's employee's answer every week into a handy guide that fits in your back pocket or alongside your keyboard.

  15. Enhanced Sleep Mode MAC Control for EPON

    DEFF Research Database (Denmark)

    Yan, Ying; Dittmann, Lars

    2011-01-01

    This paper introduces sleep mode operations for EPON. New MAC control functions are proposed to schedule sleep periods. Traffic profiles are considered to optimize energy efficiency and network performances. Simulation results are analyzed in OPNET modeler.......This paper introduces sleep mode operations for EPON. New MAC control functions are proposed to schedule sleep periods. Traffic profiles are considered to optimize energy efficiency and network performances. Simulation results are analyzed in OPNET modeler....

  16. Performance of a Wireless Sensor Network MAC Protocol with a Variable Sleep Interval

    Directory of Open Access Journals (Sweden)

    M.K. Kirubakaran

    2014-02-01

    Full Text Available A MAC protocol specifies how nodes in a sensor network access a shared communication channel. Medium access control protocols for wireless sensor networks are almost always designed to be energy efficient. Desired properties of such MAC protocol are: it should be distributed and contention-free. This study addresses low power MAC protocols utilize energy in efficient manner in wireless sensor networks. We are interested in the trade-off between power consumption and transmission delay, focusing on low traffic in EM-MAC. In EM-MAC, a significant proportion of the nodes may have to stay awake much longer than envisaged. We describe RRMAC protocol (Receiver-Reservation MAC protocol, a new protocol for the Collision avoidance and energy loss due to retransmissions and increase the life span of a wireless sensor networks. This study concludes with the result of simulation studies which indicate that the use of the proposed RRMAC protocol is expected to increase the life time of wireless sensor networks significantly.

  17. An Analysis on Decentralized Adaptive MAC Protocols for Cognitive Radio Networks

    Institute of Scientific and Technical Information of China (English)

    Munam Ali Shah; Sijing Zhang; Carsten Maple

    2013-01-01

    The scarcity of bandwidth in the radio spectrum has become more vital since the demand for more and more wireless applications has increased.Most of the spectrum bands have been allocated although many studies have shown that these bands are significantly underutilized most of the time.The problem of unavailability of spectrum and inefficiency in its utilization has been smartly addressed by the cognitive radio (CR) technology which is an opportunistic network that senses the environment,observes the network changes,and then uses knowledge gained from the prior interaction with the network to make intelligent decisions by dynamically adapting their transmission characteristics.In this paper,some of the decentralized adaptive medium access control (MAC) protocols for CR networks have been critically analyzed,and a novel adaptive MAC protocol for CR networks,decentralized non-global MAC (DNG-MAC),has been proposed.The results show the DNG-MAC outperforms other CR-MAC protocols in termsof time and energy efficiency.

  18. 42 CFR 405.1120 - Filing briefs with the MAC.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 2 2010-10-01 2010-10-01 false Filing briefs with the MAC. 405.1120 Section 405....1120 Filing briefs with the MAC. Upon request, the MAC will give the party requesting review, as well... ending with the date the brief is received by the MAC will not be counted toward the adjudication...

  19. 42 CFR 423.1974 - Medicare Appeals Council (MAC) review.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 3 2010-10-01 2010-10-01 false Medicare Appeals Council (MAC) review. 423.1974..., MAC review, and Judicial Review § 423.1974 Medicare Appeals Council (MAC) review. An enrollee who is dissatisfied with an ALJ hearing decision may request that the MAC review the ALJ's decision or dismissal as...

  20. 42 CFR 423.2130 - Effect of the MAC's decision.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 3 2010-10-01 2010-10-01 false Effect of the MAC's decision. 423.2130 Section 423... (CONTINUED) MEDICARE PROGRAM VOLUNTARY MEDICARE PRESCRIPTION DRUG BENEFIT Reopening, ALJ Hearings, MAC review, and Judicial Review § 423.2130 Effect of the MAC's decision. The MAC's decision is final and binding...

  1. 42 CFR 405.1130 - Effect of the MAC's decision.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 2 2010-10-01 2010-10-01 false Effect of the MAC's decision. 405.1130 Section 405....1130 Effect of the MAC's decision. The MAC's decision is final and binding on all parties unless a Federal district court issues a decision modifying the MAC's decision or the decision is revised as the...

  2. 42 CFR 423.2118 - Obtaining evidence from the MAC.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 3 2010-10-01 2010-10-01 false Obtaining evidence from the MAC. 423.2118 Section..., MAC review, and Judicial Review § 423.2118 Obtaining evidence from the MAC. An enrollee may request... the costs of providing these items. If an enrollee requests evidence from the MAC and an opportunity...

  3. 42 CFR 423.2126 - Case remanded by the MAC.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 3 2010-10-01 2010-10-01 false Case remanded by the MAC. 423.2126 Section 423.2126... (CONTINUED) MEDICARE PROGRAM VOLUNTARY MEDICARE PRESCRIPTION DRUG BENEFIT Reopening, ALJ Hearings, MAC review, and Judicial Review § 423.2126 Case remanded by the MAC. (a) When the MAC may remand a case to the ALJ...

  4. 42 CFR 423.2120 - Filing briefs with the MAC.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 3 2010-10-01 2010-10-01 false Filing briefs with the MAC. 423.2120 Section 423... (CONTINUED) MEDICARE PROGRAM VOLUNTARY MEDICARE PRESCRIPTION DRUG BENEFIT Reopening, ALJ Hearings, MAC review, and Judicial Review § 423.2120 Filing briefs with the MAC. Upon request, the MAC will give the...

  5. SA-MAC:Self-Stabilizing Adaptive MAC Protocol for Wireless Sensor Networks

    Institute of Scientific and Technical Information of China (English)

    波澄; 韩君泽; 李向阳; 王昱; 肖波

    2014-01-01

    A common method of prolonging the lifetime of wireless sensor networks is to use low power duty cycling protocol. Existing protocols consist of two categories: sender-initiated and receiver-initiated. In this paper, we present SA-MAC, a self-stabilizing adaptive MAC protocol for wireless sensor networks. SA-MAC dynamically adjusts the transmission time-slot, waking up time-slot, and packet detection pattern according to current network working condition, such as packet length and wake-up patterns of neighboring nodes. In the long run, every sensor node will find its own transmission phase so that the network will enter a stable stage when the network load and qualities are static. We conduct extensive experiments to evaluate the energy consumption, packet reception rate of SA-MAC in real sensor networking systems. Our results indicate that SA-MAC outperforms other existing protocols.

  6. Analytical Comparison of MAC Schemes for Energy Harvesting - Wireless Sensor Networks

    DEFF Research Database (Denmark)

    Fafoutis, Xenofon; Dragoni, Nicola

    2012-01-01

    MAC protocols for multi-hop WSNs have to address the challenge of coordinating duty-cycling transmitters with duty-cycling receivers. All the suggested protocols can be classified into three basic paradigms: the synchronization, the preamble and the beaconing paradigm. In this paper, we discuss...

  7. Massive Machine-type Communications in 5G: Physical and MAC-layer solutions

    DEFF Research Database (Denmark)

    Bockelmann, Carsten; Pratas, Nuno; Nikopout, Hosein;

    2016-01-01

    for human-type communications. Furthermore, mMTC solutions need to enable wide area coverage and deep indoor penetration while having low cost and being energy efficient. In this article, we introduce the physical (PHY) and medium access control (MAC) layer solutions developed within METIS to address...

  8. Mac OS X Snow Leopard试用

    Institute of Scientific and Technical Information of China (English)

    大大

    2009-01-01

    苹果新一代操作系统Mac OS X 10.6 Snow Leopard(雪豹)于8月底上市。根据NPD集团的统计数据,该系统在美国市场前两周的销售非常喜人,是2007年Mac OS X 10.5 Leopard上市销量的2倍以上,是2005年的Mac OS X 10.4 Tiger操作系统的售量的4倍。假如你也对升级价格仅需88元雪豹系统感兴趣,就让我们从一起升级安装开始,体验它独特的魅力。

  9. MacBook Pro Portable Genius

    CERN Document Server

    Miser, Brad

    2011-01-01

    Tips and techniques for forward-thinking MacBook Pro users Now that you have a MacBook Pro, you need just one more accessory, your very own copy of MacBook Pro Portable Genius, Third Edition. This handy, compact book lets you in on a wealth of tips and tricks, so you get the very most out of Apple's very popular notebook. Discover the latest on the most recent release of iLife, get the skinny on the new Intel Core i7 and i5 processors in the Pro, see how to go wireless in a smart way, and much more. The book is easy to navigate, doesn't skimp on the essentials, and helps you save time and avoi

  10. MacSelfService online tutorial

    CERN Document Server

    CERN. Geneva

    2016-01-01

    Mac Self-Service is a functionality within the Mac Desktop Service built and maintained to empower CERN users by giving them easy access to applications and configurations through the Self-Service application. This tutorial (text attached to the event page) explains how to install Mac Self-Service and how to use it to install applications and printers. Content owner: Vincent Nicolas Bippus Presenter: Pedro Augusto de Freitas Batista Tell us what you think via e-learning.support at cern.ch More tutorials in the e-learning collection of the CERN Document Server (CDS) https://cds.cern.ch/collection/E-learning%20modules?ln=en All info about the CERN rapid e-learning project is linked from http://twiki.cern.ch/ELearning  

  11. On Proper Selection of Multihop Relays for Future Enhancement of AeroMACS Networks

    Science.gov (United States)

    Kamali, Behnam; Kerczewski, Robert J.; Apaza, Rafael D.

    2015-01-01

    As the Aeronautical Mobile Airport Communications System (AeroMACS) has evolved from a technology concept to a deployed communications network over major US airports, it is now time to contemplate whether the existing capacity of AeroMACS is sufficient to meet the demands set forth by all fixed and mobile applications over the airport surface given the AeroMACS constraints regarding bandwidth and transmit power. The underlying idea in this article is to present IEEE 802.16j-based WiMAX as a technology that can address future capacity enhancements and therefore is most feasible for AeroMACS applications. The principal argument in favor IEEE 802.16j technology is the flexible and cost effective extension of radio coverage that is afforded by relay fortified networks, with virtually no increase in the power requirements and virtually no rise in interference levels to co-allocated applications. The IEEE 802.16j-based multihop relay systems are briefly described. The focus is on key features of this technology, frame structure, and its architecture. Next, AeroMACS is described as a WiMAX-based wireless network. The two major relay modes supported by IEEE 802.16j amendment, i.e., transparent and non-transparent are described. The benefits of employing multihop relays are listed. Some key challenges related to incorporating relays into AeroMACS networks are discussed. The selection of relay type in a broadband wireless network affects a number of network parameters such as latency, signal overhead, PHY (Scalable Physical Layer) and MAC (Media Access Layer) layer protocols, consequently it can alter key network quantities of throughput and QoS (Quality of Service).

  12. Mac OS X Snow Leopard pocket guide

    CERN Document Server

    Seiblod, Chris

    2009-01-01

    Whether you're new to the Mac or a longtime user, this handy book is the quickest way to get up to speed on Snow Leopard. Packed with concise information in an easy-to-read format, Mac OS X Snow Leopard Pocket Guide covers what you need to know and is an ideal resource for problem-solving on the fly. This book goes right to the heart of Snow Leopard, with details on system preferences, built-in applications, and utilities. You'll also find configuration tips, keyboard shortcuts, guides for troubleshooting, lots of step-by-step instructions, and more. Learn about new features and changes s

  13. MacBook Pro Portable Genius

    CERN Document Server

    Miser, Brad

    2012-01-01

    Discover loads of tips and techniques for the newest MacBook Pro You're already ahead of the game with a MacBook Pro. Now you can get even more out the popular Apple notebook with the new edition of this handy, compact book. Crammed with savvy insights and tips on key tools and shortcuts, this book will help you increase your productivity and keep your Apple digital lifestyle on track. From desktop sharing and wireless networking to running Windows applications, this book avoids fluff, doesn't skimp on the essentials, saves you time and hassle, and shows you what you most want to know. Include

  14. MAC2: A Multi-Hop Adaptive MAC Protocol with Packet Concatenation for Wireless Sensor Networks

    Science.gov (United States)

    Nguyen, Kien; Meis, Ulrich; Ji, Yusheng

    Wireless sensor network MAC protocols switch radios off periodically, employing the so-called duty cycle mechanism, in order to conserve battery power that would otherwise be wasted by energy-costly idle listening. In order to minimize the various negative side-effects of the original scheme, especially on latency and throughput, various improvements have been proposed. In this paper, we introduce a new MAC protocol called MAC2(Multi-hop Adaptive with packet Concatenation-MAC) which combines three promising techniques into one protocol. Firstly, the idea to forward packets over multiple hops within one operational cycle as initially introduced in RMAC. Secondly, an adaptive method that adjusts the listening period according to traffic load minimizing idle listening. Thirdly, a packet concatenation scheme that not only increases throughput but also reduces power consumption that would otherwise be incurred by additional control packets. Furthermore, MAC2 incorporates the idea of scheduling data transmissions with minimum latency, thereby performing packet concatenation together with the multi-hop transmission mechanism in a most efficient way. We evaluated MAC2 using the prominent network simulator ns-2 and the results show that our protocol can outperform DW-MAC — a state of the art protocol both in terms of energy efficiency and throughput.

  15. Efficient MAC Protocol for Hybrid Wireless Network with Heterogeneous Sensor Nodes

    Directory of Open Access Journals (Sweden)

    Md. Nasre Alam

    2016-01-01

    Full Text Available Although several Directional Medium Access Control (DMAC protocols have been designed for use with homogeneous networks, it can take a substantial amount of time to change sensor nodes that are equipped with an omnidirectional antenna for sensor nodes with a directional antenna. Thus, we require a novel MAC protocol for use with an intermediate wireless network that consists of heterogeneous sensor nodes equipped with either an omnidirectional antenna or a directional antenna. The MAC protocols that have been designed for use in homogeneous networks are not suitable for use in a hybrid network due to deaf, hidden, and exposed nodes. Therefore, we propose a MAC protocol that exploits the characteristics of a directional antenna and can also work efficiently with omnidirectional nodes in a hybrid network. In order to address the deaf, hidden, and exposed node problems, we define RTS/CTS for the neighbor (RTSN/CTSN and Neighbor Information (NIP packets. The performance of the proposed MAC protocol is evaluated through a numerical analysis using a Markov model. In addition, the analytical results of the MAC protocol are verified through an OPNET simulation.

  16. Results from the MAC Vertex chamber

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, H.N.

    1987-05-01

    The design, construction, and performance characteristics of a high precision gaseous drift chamber made of thin walled proportional tubes are described. The device achieved an average spatial resolution of 45 ..mu..m in use for physics analysis with the MAC detector. The B-lifetime result obtained with this chamber is discussed.

  17. MacIntyre, Managerialism and Universities

    Science.gov (United States)

    Stolz, Steven A.

    2017-01-01

    MacIntyre's earlier work and concern with social science enquiry not only exposes its limits, but also provides an insight into how its knowledge claims have been put to ideological use. He maintains that the institutional embodiment of these ideological ideas is the bureaucratic manager who has had a negative role to play in social structures…

  18. AH-MAC: Adaptive Hierarchical MAC Protocol for Low-Rate Wireless Sensor Network Applications

    Directory of Open Access Journals (Sweden)

    Adnan Ismail Al-Sulaifanie

    2017-01-01

    Full Text Available This paper proposes an adaptive hierarchical MAC protocol (AH-MAC with cross-layer optimization for low-rate and large-scale wireless sensor networks. The main goal of the proposed protocol is to combine the strengths of LEACH and IEEE 802.15.4 while offsetting their weaknesses. The predetermined cluster heads are supported with an energy harvesting circuit, while the normal nodes are battery-operated. To prolong the network’s operational lifetime, the proposed protocol transfers most of the network’s activities to the cluster heads while minimizing the node’s activity. Some of the main features of this protocol include energy efficiency, self-configurability, scalability, and self-healing. The simulation results showed great improvement of the AH-MAC over LEACH protocol in terms of energy consumption and throughput. AH-MAC consumes eight times less energy while improving throughput via acknowledgment support.

  19. CA-MAC: A Novel MAC Protocol to Alleviate Congestion in Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    WU, J.

    2013-11-01

    Full Text Available Even if the traffic pattern is known and the network topology is simple, a strong congestion can take place in wireless sensor networks (WSNs due to the data gathering effect and the duty-cycle operation. In this paper, we propose a novel medium access control (MAC protocol to alleviate the congestion, which is referred to as the congestion alleviation-MAC (CA-MAC. It adopts an adaptive contention window (ACW, which allows the nodes with more buffered packets to transmit with a higher probability, as well as an intelligent burst packet transmission when the congested nodes seize the channel. Simulations are performed in NS-2, and results show that the proposed CA-MAC protocol achieves a good performance in terms of the packet delivery ratio (PDR, power consumption, throughput, and average latency.

  20. Exposure histories of lunar meteorites: ALHA81005, MAC88104, MAC88105, and Y791197

    Energy Technology Data Exchange (ETDEWEB)

    Nishiizumi, K.; Arnold, J.R. (Univ. of California, San Diego, (United States)); Klein, J.; Fink, D.; Middleton, R. (Univ. of Pennsylvania, Philadelphia (United States)); Kubik, P.W.; Sharma, P.; Elmore, D. (Univ. of Rochester, NY (United States)); Reedy, R.C. (Los Alamos National Lab., NM (United States))

    1991-11-01

    The cosmogenic radionuclides {sup 41}Ca, {sup 36}Cl, {sup 26}Al, and {sup 10}Be in the Allan Hills 81005, MacAlpine Hills 88104, MacAlpine Hills 88105,and Yamato 791197 meteorites were measured by accelerator mass spectrometry (AMS). {sup 53}Mn in Allan Hills 81005 and Yamato 791197 was measured by activation. These four lunar meteorites experienced similar histories. They were ejected from near the surface of the Moon ranging in depth down to 400 g/cm{sup 2} and had very short transition times (less than 0.1 Ma) from the Moon to the Earth. A comparison of the cosmogenic nuclide concentrations in MacAlpine Hills 88104 and MacAlpine Hills 88105 clearly indicates that they are a pair from the same fall.

  1. 42 CFR 405.1126 - Case remanded by the MAC.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 2 2010-10-01 2010-10-01 false Case remanded by the MAC. 405.1126 Section 405.1126....1126 Case remanded by the MAC. (a) When the MAC may remand a case. Except as specified in § 405.1122(c), the MAC may remand a case in which additional evidence is needed or additional action by the ALJ is...

  2. Welcome Address

    OpenAIRE

    Shantanu Sengupta

    1983-01-01

    This article is part of the NEDA-PIDS Seminar-Workshop on the Philippine System of National Accounts. It outlines the seminar’s major objectives and the problems and issues that need to be addressed. It argues that coordination among institutions can lead to effective resolution to sensitive issues.

  3. Reduction in standard MAC and MAC for intubation after clonidine premedication in children.

    Science.gov (United States)

    Inomata, S; Kihara, S; Yaguchi, Y; Baba, Y; Kohda, Y; Toyooka, H

    2000-11-01

    We examined the relative effects of different doses of oral clonidine on the MAC for endotracheal intubation (MACEI) and the MAC for skin incision (MAC) in children. We studied 90 children (15 in each group) (age range 2-8 yr, weight 10-27 kg, height 89-124 cm) who received one of three preanaesthetic medications: placebo (control), oral clonidine 2 micrograms kg-1, or oral clonidine 4 micrograms kg-1 100 min before anaesthesia. Anaesthesia was induced and maintained with sevoflurane in oxygen and air without i.v. anesthetics and neuromuscular relaxants. The end-tidal sevoflurane concentration was kept constant for > or = 15 min before tracheal intubation or skin incision. MACs were determined using Dixon's 'up-and-down method'. Mean (SD) MACEIs of sevoflurane were 2.9 (0.1)%, 2.5 (0.1)% and 1.9 (0.1)% (P clonidine 2 micrograms kg-1 and clonidine 4 micrograms kg-1 groups. The MACEIs and MACs decreased dose-dependently. The MACEI/MAC ratio (1.4) was not affected by clonidine.

  4. CR-MAC: A Multichannel MAC Protocol for Cognitive Radio AD HOC Networks

    Directory of Open Access Journals (Sweden)

    S. M. Kamruzzaman

    2010-09-01

    Full Text Available This paper proposes a cross-layer based cognitive radio multichannel medium access control (MACprotocol with TDMA, which integrate the spectrum sensing at physical (PHY layer and the packetscheduling at MAC layer, for the ad hoc wireless networks. The IEEE 802.11 standard allows for the useof multiple channels available at the PHY layer, but its MAC protocol is designed only for a singlechannel. A single channel MAC protocol does not work well in a multichannel environment, because ofthe multichannel hidden terminal problem. Our proposed protocol enables secondary users (SUs toutilize multiple channels by switching channels dynamically, thus increasing network throughput. In ourproposed protocol, each SU is equipped with only one spectrum agile transceiver, but solves themultichannel hidden terminal problem using temporal synchronization. The proposed cognitive radioMAC (CR-MAC protocol allows SUs to identify and use the unused frequency spectrum in a way thatconstrains the level of interference to the primary users (PUs. Our scheme improves network throughputsignificantly, especially when the network is highly congested. The simulation results show that ourproposed CR-MAC protocol successfully exploits multiple channels and significantly improves networkperformance by using the licensed spectrum band opportunistically and protects PUs from interference,even in hidden terminal situations.

  5. 42 CFR 423.2128 - Action of the MAC.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 3 2010-10-01 2010-10-01 false Action of the MAC. 423.2128 Section 423.2128 Public...) MEDICARE PROGRAM VOLUNTARY MEDICARE PRESCRIPTION DRUG BENEFIT Reopening, ALJ Hearings, MAC review, and Judicial Review § 423.2128 Action of the MAC. (a) After it has reviewed all the evidence in the...

  6. 42 CFR 405.1118 - Obtaining evidence from the MAC.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 2 2010-10-01 2010-10-01 false Obtaining evidence from the MAC. 405.1118 Section... Council Review § 405.1118 Obtaining evidence from the MAC. A party may request and receive a copy of all... these items. If a party requests evidence from the MAC and an opportunity to comment on that evidence...

  7. 42 CFR 405.1128 - Action of the MAC.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 2 2010-10-01 2010-10-01 false Action of the MAC. 405.1128 Section 405.1128 Public... the MAC. (a) After it has reviewed all the evidence in the administrative record and any additional evidence received, subject to the limitations on MAC consideration of additional evidence in § 405.1122...

  8. 42 CFR 422.608 - Medicare Appeals Council (MAC) review.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 3 2010-10-01 2010-10-01 false Medicare Appeals Council (MAC) review. 422.608... and Appeals § 422.608 Medicare Appeals Council (MAC) review. Any party to the hearing, including the MA organization, who is dissatisfied with the ALJ hearing decision, may request that the MAC review...

  9. MAC 700 Wash高亮度灯具

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    马田最新推出的MAC 700 Wash高亮度灯具继承了MAC系列的传统优点.具有与MAC 700 Profile相同的强大功能、模组桔构和出色设计,是MAC 700 Profile的“最佳搭档”。

  10. Isolation and characterisation of human gingival margin-derived STRO-1/MACS1 and MACS2 cell populations

    Institute of Scientific and Technical Information of China (English)

    Karim M Fawzy El-Sayed; Sebastian Paris; Christian Graetz; Neemat Kassem; Mohamed Mekhemar; Hendrick Ungefroren; Fred Fandrich; Christof Dorfer

    2015-01-01

    Recently, gingival margin-derived stem/progenitor cells isolated via STRO-1/magnetic activated cell sorting (MACS) showed remarkable periodontal regenerative potential in vivo. As a second-stage investigation, the present study’s aim was to perform in vitro characterisation and comparison of the stem/progenitor cell characteristics of sorted STRO-1-positive (MACS1) and STRO-1-negative (MACS2) cell populations from the human free gingival margin. Cells were isolated from the free gingiva using a minimally invasive technique and were magnetically sorted using anti-STRO-1 antibodies. Subsequently, the MACS1 and MACS2 cell fractions were characterized by flow cytometry for expression of CD14, CD34, CD45, CD73, CD90, CD105, CD146/MUC18 and STRO-1. Colony-forming unit (CFU) and multilineage differentiation potential were assayed for both cell fractions. Mineralisation marker expression was examined using real-time polymerase chain reaction (PCR). MACS1 and MACS2 cell fractions showed plastic adherence. MACS1 cells, in contrast to MACS2 cells, showed all of the predefined mesenchymal stem/progenitor cell characteristics and a significantly higher number of CFUs (P,0.01). More than 95%of MACS1 cells expressed CD105, CD90 and CD73;lacked the haematopoietic markers CD45, CD34 and CD14, and expressed STRO-1 and CD146/MUC18. MACS2 cells showed a different surface marker expression profile, with almost no expression of CD14 or STRO-1, and more than 95%of these cells expressed CD73, CD90 and CD146/MUC18, as well as the haematopoietic markers CD34 and CD45 and CD105. MACS1 cells could be differentiated along osteoblastic, adipocytic and chondroblastic lineages. In contrast, MACS2 cells demonstrated slight osteogenic potential. Unstimulated MACS1 cells showed significantly higher expression of collagen I (P,0.05) and collagen III (P,0.01), whereas MACS2 cells demonstrated higher expression of osteonectin (P,0.05;Mann–Whitney). The present study is the first to compare gingival

  11. Modeling MAC layer for powerline communications networks

    Science.gov (United States)

    Hrasnica, Halid; Haidine, Abdelfatteh

    2001-02-01

    The usage of electrical power distribution networks for voice and data transmission, called Powerline Communications, becomes nowadays more and more attractive, particularly in the telecommunication access area. The most important reasons for that are the deregulation of the telecommunication market and a fact that the access networks are still property of former monopolistic companies. In this work, first we analyze a PLC network and system structure as well as a disturbance scenario in powerline networks. After that, we define a logical structure of the powerline MAC layer and propose the reservation MAC protocols for the usage in the PLC network which provides collision free data transmission. This makes possible better network utilization and realization of QoS guarantees which can make PLC networks competitive to other access technologies.

  12. Seán MacDiarmada

    Directory of Open Access Journals (Sweden)

    Madden

    2016-12-01

    Full Text Available Seán MacDiarmada: Signatory to Proclamation – Executed after the Rising of 1916 - Leitrim to Kilmainham was written by Tom Madden to coincide with the 1916/2016 centenary commemorations. The play was first performed at the Mullagh Arts Festival in Cavan during September 2016 and provides a lively account of the background and activism of one the seven leaders of the Easter Rising of 1916. The action plays out over twelve scenes taking in MacDiarmada's journey from teacher to revolutionary activist culminating in a deeply flawed court-martial and his subsequent execution by a British Army firing squad on May 12th, 1916.

  13. Earth tides in MacDonald's model

    CERN Document Server

    Ferraz-Mello, S

    2013-01-01

    We expand the equations used in MacDonald's 1964 theory and Fourier analyze the tidal variations of the height at one point on the Earth surface, and also the tidal potential at such point. It is shown that no intrinsic law is relating the lag of the tide components to their frequencies. In other words, no simple rheology is being intrinsically fixed by MacDonald's equations. The same is true of the modification proposed by Singer(1968). At variance with these two cases, the modification proposed by Williams and Efroimsky (2012) fix the standard Darwin rheology in which the lags are proportional to the frequencies and their model is, in this sense, equivalent to Mignard's 1979 formulation of Darwin's theory.

  14. MacBook Pro portable genius

    CERN Document Server

    Gruman, Galen

    2013-01-01

    Learn the skills, tools and shortcuts you need in order to make the most of your MacBook Pro This easy-to-use, compact guide skips the fluff and gets right to the essentials so that you can maximize all the latest features of the MacBook Pro. Packed with savvy insights and tips on key tools and shortcuts, this handy book aims to help you increase your productivity and save you time and hassle. From desktop sharing and wireless networking to running Windows applications and more, this book shows you what you want to know. Includes the latest version of OS X, iCloud, FaceTime, and moreCovers al

  15. Performance Analysis of MAC Layer Protocols in Wireless Sensor Network

    Directory of Open Access Journals (Sweden)

    Hameeza Ahmed

    2014-10-01

    Full Text Available Media Access Control (MAC layer protocols have a critical role in making a typical Wireless Sensor Network (WSN more reliable and efficient. Choice of MAC layer protocol and other factors including number of nodes, mobility, traffic rate and playground size dictates the performance of a particular WSN. In this paper, the performance of an experimental WSN is evaluated using different MAC layer protocols. In this experiment, a WSN is created using OMNeT++ MiXiM network simulator and its performance in terms of packet delivery ratio and mean latency is evaluated. The simulation results show that IEEE 802.11 MAC layer protocol performs better than CSMA, B-MAC and IEEE 802.15.4 MAC layer protocols. In the considered scenario, IEEE 802.15.4 is ranked second in performance, followed by CSMA and B-MAC.

  16. 关于Mac OS X Lion

    Institute of Scientific and Technical Information of China (English)

    饭桶

    2011-01-01

    Lion是Mac OS X操作系统的第七个版本,第一个版本是2001年发布的Cheetah(猎豹).或许很多Windows用户会认为,Lion不过是一次升级,主版本仍然是Mac OSX.那么我不介意稍微解释一下:Mac OS X对应的层次是Windows,Cheetah或者Lion相当于XP,或者7.因此即使从软件工程的角度看,Lion也是一个全新的操作系统.由于重新编译了核心,Lion的安装文件只有3.6GB大小,比上一代(Snow Leopard)减少了近一半的体积,这种比旧版本体积更小的新操作系统在历史上可不多见.

  17. Power Saving MAC Protocols for WSNs and Optimization of S-MAC Protocol

    Directory of Open Access Journals (Sweden)

    Simarpreet Kaur

    2012-11-01

    Full Text Available Low power MAC protocols have received a lot of consideration in the last few years because of their influence on the lifetime of wireless sensor networks. Since, sensors typically operate on batteries, replacement of which is often difficult. A lot of work has been done to minimize the energy expenditure and prolong the sensor lifetime through energy efficient designs, across layers. Meanwhile, the sensor network should be able to maintain a certain throughput in order to fulfill the QoS requirements of the end user, and to ensure the constancy of the network. This paper introduces different types of MAC protocols used for WSNs and proposes S‐MAC, a Medium‐Access Control protocol designed for Wireless Sensor Networks. S‐MAC uses a few innovative techniques to reduce energy consumption and support selfconfiguration. A new protocol is suggested to improve the energy efficiency, latency and throughput of existing MAC protocol for WSNs. A modification of the protocol is then proposed to eliminate the need for some nodes to stay awake longer than the other nodes which improves the energy efficiency, latency and throughput and hence increases the life span of a wireless sensor network.

  18. SR-MAC: A Low Latency MAC Protocol for Multi-Packet Transmissions in Wireless Sensor Networks

    Institute of Scientific and Technical Information of China (English)

    Hong-Wei Tang; Jian-Nong Cao; Xue-Feng Liu; Cai-Xia Sun

    2013-01-01

    Event detection is one of the major applications of wireless sensor networks (WSNs).Most of existing medium access control (MAC) protocols are mainly optimized for the situation under which an event only generates one packet on a single sensor node.When an event generates multiple packets on a single node,the performance of these MAC protocols degrades rapidly.In this paper,we present a new synchronous duty-cycle MAC protocol called SR-MAC for the event detection applications in which multiple packets are generated on a single node.SR-MAC introduces a new scheduling mechanism that reserves few time slots during the SLEEP period for the nodes to transmit multiple packets.By this approach,SR-MAC can schedule multiple packets generated by an event on a single node to be forwarded over multiple hops in one operational cycle without collision.We use event delivery latency (EDL) and event delivery ratio (EDR) to measure the event detection capability of the SR-MAC protocol.Through detailed ns-2 simulation,the results show that SR-MAC can achieve lower EDL,higher EDR and higher network throughput with guaranteed energy efficiency compared with R-MAC,DW-MAC and PR-MAC.

  19. Welcome Address

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    @@  On behalf of the International Life Sciences Institute, I welcome you to Beijing and to the Third Asian Conference on Food Safety and Nutrition. Many of you will remember the first Asian conference on Food Safety held in Kuala Lumpur in 1990 and the second held in Bangkok in 1994. These meetings have been so successful that ILSI made the commitment to host such a conference periodically in order to provide a forum to share the latest information and to set new goals and priorities.   This year, we have broadened the scope of the agenda to include issues on nutrition. I want to thank all of our co-sponsors and members of the Planning Committee for preparing such a comprehensive and timely program. Some of the issues and challenges facing Asia that will be addressed at this meeting are:

  20. W-MAC: a workload-aware MAC protocol for heterogeneous convergecast in wireless sensor networks.

    Science.gov (United States)

    Xia, Ming; Dong, Yabo; Lu, Dongming

    2011-01-01

    The power consumption and latency of existing MAC protocols for wireless sensor networks (WSNs) are high in heterogeneous convergecast, where each sensor node generates different amounts of data in one convergecast operation. To solve this problem, we present W-MAC, a workload-aware MAC protocol for heterogeneous convergecast in WSNs. A subtree-based iterative cascading scheduling mechanism and a workload-aware time slice allocation mechanism are proposed to minimize the power consumption of nodes, while offering a low data latency. In addition, an efficient schedule adjustment mechanism is provided for adapting to data traffic variation and network topology change. Analytical and simulation results show that the proposed protocol provides a significant energy saving and latency reduction in heterogeneous convergecast, and can effectively support data aggregation to further improve the performance.

  1. Notas sobre dois livros de MacIntyre Notes on two books by MacIntyre

    Directory of Open Access Journals (Sweden)

    Isabel Ribeiro de Oliveira

    2005-04-01

    Full Text Available Os conceitos centrais da teoria da justiça desenvolvida por Alasdair MacIntyre - prática, narrativa e tradição - ocupam o núcleo da análise feita acerca de dois de seus livros: Depois da Virtude e Justiça de Quem? Qual racionalidade?. O artigo considera a relação, em MacIntyre, entre ética e história, virtude e relativismo, bem como apresenta seu conceito do Eu, como corretivos à anomia contemporânea.The central concepts of MacIntyre's approach to justice - practice, narrative and tradition - constitute the main trust of the analysis of two of his books: After Virtue and Whose justice? Which rationality? The article elaborates on the relationship of ethics to history, of virtues to relativism as well as his conception of the self as correctives to the pervasive anomie in contemporary societies.

  2. Inaugural address

    Science.gov (United States)

    Joshi, P. S.

    2014-03-01

    From jets to cosmos to cosmic censorship P S Joshi Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005, India E-mail: psj@tifr.res.in 1. Introduction At the outset, I should like to acknowledge that part of the title above, which tries to capture the main flavour of this meeting, and has been borrowed from one of the plenary talks at the conference. When we set out to make the programme for the conference, we thought of beginning with observations on the Universe, but then we certainly wanted to go further and address deeper questions, which were at the very foundations of our inquiry, and understanding on the nature and structure of the Universe. I believe, we succeeded to a good extent, and it is all here for you in the form of these Conference Proceedings, which have been aptly titled as 'Vishwa Mimansa', which could be possibly translated as 'Analysis of the Universe'! It is my great pleasure and privilege to welcome you all to the ICGC-2011 meeting at Goa. The International Conference on Gravitation and Cosmology (ICGC) series of meetings are being organized by the Indian Association for General Relativity and Gravitation (IAGRG), and the first such meeting was planned and conducted in Goa in 1987, with subsequent meetings taking place at a duration of about four years at various locations in India. So, it was thought appropriate to return to Goa to celebrate the 25 years of the ICGC meetings. The recollections from that first meeting have been recorded elsewhere here in these Proceedings. The research and teaching on gravitation and cosmology was initiated quite early in India, by V V Narlikar at the Banares Hindu University, and by N R Sen in Kolkata in the 1930s. In course of time, this activity grew and gained momentum, and in early 1969, at the felicitation held for the 60 years of V V Narlikar at a conference in Ahmedabad, P C Vaidya proposed the formation of the IAGRG society, with V V Narlikar being the first President. This

  3. A novel distributed algorithm for media access control address assignment in wireless sensor networks

    Institute of Scientific and Technical Information of China (English)

    TIAN Ye; SHENG Min; LI Jiandong

    2007-01-01

    This Paper presents a novel distributed media access control(MAC)address assignment algorithm,namely virtual grid spatial reusing(VGSR),for wireless sensor networks,which reduces the size of the MAC address efficiently on the basis of both the spatial reuse of MAC address and the mapping of geographical position.By adjusting the communication range of sensor nodes,VGSR algorithm can minimize the size of MAC address and meanwhile guarantee the connectivity of the sensor network.Theoretical analysis and experimental results show that VGSR algorithm is not only of low energy cost,but also scales well with the network ize,with its performance superior to that of other existing algorithms.

  4. A Survey of MAC Protocols for Cognitive Radio Body Area Networks

    Science.gov (United States)

    Bhandari, Sabin; Moh, Sangman

    2015-01-01

    The advancement in electronics, wireless communications and integrated circuits has enabled the development of small low-power sensors and actuators that can be placed on, in or around the human body. A wireless body area network (WBAN) can be effectively used to deliver the sensory data to a central server, where it can be monitored, stored and analyzed. For more than a decade, cognitive radio (CR) technology has been widely adopted in wireless networks, as it utilizes the available spectra of licensed, as well as unlicensed bands. A cognitive radio body area network (CRBAN) is a CR-enabled WBAN. Unlike other wireless networks, CRBANs have specific requirements, such as being able to automatically sense their environments and to utilize unused, licensed spectra without interfering with licensed users, but existing protocols cannot fulfill them. In particular, the medium access control (MAC) layer plays a key role in cognitive radio functions, such as channel sensing, resource allocation, spectrum mobility and spectrum sharing. To address various application-specific requirements in CRBANs, several MAC protocols have been proposed in the literature. In this paper, we survey MAC protocols for CRBANs. We then compare the different MAC protocols with one another and discuss challenging open issues in the relevant research. PMID:25903551

  5. A Survey of MAC Protocols for Cognitive Radio Body Area Networks.

    Science.gov (United States)

    Bhandari, Sabin; Moh, Sangman

    2015-04-20

    The advancement in electronics, wireless communications and integrated circuits has enabled the development of small low-power sensors and actuators that can be placed on, in or around the human body. A wireless body area network (WBAN) can be effectively used to deliver the sensory data to a central server, where it can be monitored, stored and analyzed. For more than a decade, cognitive radio (CR) technology has been widely adopted in wireless networks, as it utilizes the available spectra of licensed, as well as unlicensed bands. A cognitive radio body area network (CRBAN) is a CR-enabled WBAN. Unlike other wireless networks, CRBANs have specific requirements, such as being able to automatically sense their environments and to utilize unused, licensed spectra without interfering with licensed users, but existing protocols cannot fulfill them. In particular, the medium access control (MAC) layer plays a key role in cognitive radio functions, such as channel sensing, resource allocation, spectrum mobility and spectrum sharing. To address various application-specific requirements in CRBANs, several MAC protocols have been proposed in the literature. In this paper, we survey MAC protocols for CRBANs. We then compare the different MAC protocols with one another and discuss challenging open issues in the relevant research.

  6. The Impact of Dynamic RTS Threshold Adjustment for IEEE 802.11 MAC Protocol

    OpenAIRE

    Mostafa Mjidi; Debasish Chakraborty; Naoki Nakamura; Norio Shiratori

    2009-01-01

    In recent years, wireless technologies and application received great attention. The Medium Access Control (MAC) protocol is the main element that determines the efficiency in sharing the limited communication bandwidth of the wireless channel in wireless local area networks (WLANs). IEEE 802.11 introduced the optional RTS/CTS handshaking mechanism to address the hidden terminal problem as well as to reduces the chance of collision in case of higher node density and traffic. RTS Threshold (RT...

  7. Presidential address.

    Science.gov (United States)

    Vohra, U

    1993-07-01

    The Secretary of India's Ministry of Health and Family Welfare serves as Chair of the Executive Council of the International Institute for Population Sciences in Bombay. She addressed its 35th convocation in 1993. Global population stands at 5.43 billion and increases by about 90 million people each year. 84 million of these new people are born in developing countries. India contributes 17 million new people annually. The annual population growth rate in India is about 2%. Its population size will probably surpass 1 billion by the 2000. High population growth rates are a leading obstacle to socioeconomic development in developing countries. Governments of many developing countries recognize this problem and have expanded their family planning programs to stabilize population growth. Asian countries that have done so and have completed the fertility transition include China, Japan, Singapore, South Korea, and Thailand. Burma, Malaysia, North Korea, Sri Lanka, and Vietnam have not yet completed the transition. Afghanistan, Bangladesh, Iran, Nepal, and Pakistan are half-way through the transition. High population growth rates put pressure on land by fragmenting finite land resources, increasing the number of landless laborers and unemployment, and by causing considerable rural-urban migration. All these factors bring about social stress and burden civic services. India has reduced its total fertility rate from 5.2 to 3.9 between 1971 and 1991. Some Indian states have already achieved replacement fertility. Considerable disparity in socioeconomic development exists among states and districts. For example, the states of Bihar, Madhya Pradesh, Rajasthan, and Uttar Pradesh have female literacy rates lower than 27%, while that for Kerala is 87%. Overall, infant mortality has fallen from 110 to 80 between 1981 and 1990. In Uttar Pradesh, it has fallen from 150 to 98, while it is at 17 in Kerala. India needs innovative approaches to increase contraceptive prevalence rates

  8. Filter arrays

    Energy Technology Data Exchange (ETDEWEB)

    Page, Ralph H.; Doty, Patrick F.

    2017-08-01

    The various technologies presented herein relate to a tiled filter array that can be used in connection with performance of spatial sampling of optical signals. The filter array comprises filter tiles, wherein a first plurality of filter tiles are formed from a first material, the first material being configured such that only photons having wavelengths in a first wavelength band pass therethrough. A second plurality of filter tiles is formed from a second material, the second material being configured such that only photons having wavelengths in a second wavelength band pass therethrough. The first plurality of filter tiles and the second plurality of filter tiles can be interspersed to form the filter array comprising an alternating arrangement of first filter tiles and second filter tiles.

  9. Welcome Address

    Science.gov (United States)

    Kiku, H.

    2014-12-01

    Ladies and Gentlemen, It is an honor for me to present my welcome address in the 3rd International Workshop on "State of the Art in Nuclear Cluster Physics"(SOTANCP3), as the president of Kanto Gakuin University. Particularly to those from abroad more than 17 countries, I am very grateful for your participation after long long trips from your home to Yokohama. On the behalf of the Kanto Gakuin University, we certainly welcome your visit to our university and stay in Yokohama. First I would like to introduce Kanto Gakuin University briefly. Kanto Gakuin University, which is called KGU, traces its roots back to the Yokohama Baptist Seminary founded in 1884 in Yamate, Yokohama. The seminary's founder was Albert Arnold Bennett, alumnus of Brown University, who came to Japan from the United States to establish a theological seminary for cultivating and training Japanese missionaries. Now KGU is a major member of the Kanto Gakuin School Corporation, which is composed of two kindergartens, two primary schools, two junior high schools, two senior high schools as well as KGU. In this university, we have eight faculties with graduate school including Humanities, Economics, Law, Sciences and Engineering, Architecture and Environmental Design, Human and Environmental Studies, Nursing, and Law School. Over eleven thousands students are currently learning in our university. By the way, my major is the geotechnical engineering, and I belong to the faculty of Sciences and Engineering in my university. Prof. T. Yamada, here, is my colleague in the same faculty. I know that the nuclear physics is one of the most active academic fields in the world. In fact, about half of the participants, namely, more than 50 scientists, come from abroad in this conference. Moreover, I know that the nuclear physics is related to not only the other fundamental physics such as the elementary particle physics and astrophysics but also chemistry, medical sciences, medical cares, and radiation metrology

  10. Monitored Anaesthesia Care (MAC in antalgic surgery

    Directory of Open Access Journals (Sweden)

    Giovanni Maria Pisanu

    2011-09-01

    Full Text Available The use of surgical techniques for pain relief in the treatment of chronic-persistent pain unresponsive to drug therapy is experiencing a growing spread application in algology. These techniques have set themselves the goal of removing the pain after treatment. Therefore, not always, percutaneous or open procedures are carried out with due precaution necessary to alleviate the patient discomfort and suffering during the surgical intervention. We present our personal experience in the use of this technique Monitored Anaesthesia Care (MAC for patients undergoing surgical treatment of pain management at our Regional Center of Pain Management.

  11. One of the First Portable Macs

    CERN Multimedia

    1989-01-01

    It was one of the first portable macs released. The Portable had many new advances in mobile computing : The display was crispy clear, and looked beautiful when used in daylight ; The Portable came with a Lead-acid gel/cell battery that could run a anywhere from 6 -12 hours ; It supported to internal hard drives, and an external one. The reaction to the laptop was weak because it was slow, it had no capacity for expansion, it weighed heavily, its price was expensive. It has been stayed 1 year and half on the market.

  12. Energy Efficient MAC for Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Pekka KOSKELA

    2010-10-01

    Full Text Available This paper considers an overlay solution for asynchronous Medium Access Control (MAC protocols in a duty-cycled wireless sensor network (WSN. The solution extends sleeping times and corrects time drift when the sampling rate is low. The sleeping time is adjusted according to the requisite data sampling rate and the delay requirements of the prevailing application. This and the time drift correction considerably reduced idle listening and thus also decreased power consumption. When the power consumption is reduced, the life of wireless sensor nodes extends.

  13. Implementation of MAC by using Modified Vedic Multiplier

    OpenAIRE

    2013-01-01

    Multiplier Accumulator Unit (MAC) is a part of Digital Signal Processors. The speed of MAC depends on the speed of multiplier. So by using an efficient Vedic multiplier which excels in terms of speed, power and area, the performance of MAC can be increased. For this fast method of multiplication based on ancient Indian Vedic mathematics is proposed in this paper. Among various method of multiplication in Vedic mathematics, Urdhva Tiryagbhyam is used and the multiplication is for 32 X 32 bits....

  14. Essential Mac OS X panther server administration integrating Mac OS X server into heterogeneous networks

    CERN Document Server

    Bartosh, Michael

    2004-01-01

    If you've ever wondered how to safely manipulate Mac OS X Panther Server's many underlying configuration files or needed to explain AFP permission mapping--this book's for you. From the command line to Apple's graphical tools, the book provides insight into this powerful server software. Topics covered include installation, deployment, server management, web application services, data gathering, and more

  15. APC-MAC/TA: Adaptive Power Controlled MAC Protocol with Traffic Awareness for Wireless Sensor Networks

    Science.gov (United States)

    Woo, Seok; Kim, Kiseon

    In this paper, we propose an adaptive power controlled MAC protocol with a traffic-aware scheme specifically designed to reduce both energy and latency in wireless sensor networks. Typically, existing MAC protocols for sensor networks sacrifice latency performance for node energy efficiency. However, some sensor applications for emergencies require rather fast transmissions of sensed data, where we need to consider both energy and latency together. The proposed MAC protocol includes two novel ideas: one is a transmission power control scheme for improving latency in high traffic loads, and the other is a traffic-aware scheme to save more energy in low traffic loads. The transmission power control scheme increases channel utilization by mitigating interference between nodes, and the traffic-aware scheme allows nodes to sleep to reduce idle energy consumption when there are no traffic loads in a network. Simulation results show that the proposed protocol significantly reduces the latency as well as the energy consumption compared to the S-MAC protocol specifically for a large transmission power of nodes and low network traffic.

  16. Weighted guided image filtering.

    Science.gov (United States)

    Li, Zhengguo; Zheng, Jinghong; Zhu, Zijian; Yao, Wei; Wu, Shiqian

    2015-01-01

    It is known that local filtering-based edge preserving smoothing techniques suffer from halo artifacts. In this paper, a weighted guided image filter (WGIF) is introduced by incorporating an edge-aware weighting into an existing guided image filter (GIF) to address the problem. The WGIF inherits advantages of both global and local smoothing filters in the sense that: 1) the complexity of the WGIF is O(N) for an image with N pixels, which is same as the GIF and 2) the WGIF can avoid halo artifacts like the existing global smoothing filters. The WGIF is applied for single image detail enhancement, single image haze removal, and fusion of differently exposed images. Experimental results show that the resultant algorithms produce images with better visual quality and at the same time halo artifacts can be reduced/avoided from appearing in the final images with negligible increment on running times.

  17. Mac OS X Snow Leopard Server For Dummies

    CERN Document Server

    Rizzo, John

    2009-01-01

    Making Everything Easier!. Mac OS® X Snow Leopard Server for Dummies. Learn to::;. Set up and configure a Mac network with Snow Leopard Server;. Administer, secure, and troubleshoot the network;. Incorporate a Mac subnet into a Windows Active Directory® domain;. Take advantage of Unix® power and security. John Rizzo. Want to set up and administer a network even if you don't have an IT department? Read on!. Like everything Mac, Snow Leopard Server was designed to be easy to set up and use. Still, there are so many options and features that this book will save you heaps of time and effort. It wa

  18. Energy-efficient MAC protocols for Wireless Sensor Networks

    Institute of Scientific and Technical Information of China (English)

    Li De-liang; Peng Fei

    2009-01-01

    Designing energy-efficient Medium Access Control (MAC) protocols has a significant influence on the energy performance of wireless sensor network (WSN). In this paper we present a survey of the recent typical MAC protocols regarding energy efficiency for WSN. According to channel access policies, we classify these protocols into four categories: contention-based, TDMA-based, hybrid, and cross layer protocols, in which the advantages and disadvantages in each class of MAC protocols are discussed. Finally, we point out open research issues that need to carry on to achieve high energy efficiency for the design of MAC protocols in WSN.

  19. Study on intracellular trafficking of Mac-1 by direct visualization

    Institute of Scientific and Technical Information of China (English)

    YAN Ming; MAO Jifang; WEI Yi; ZHONG Jigen; YANG Shengsheng; XU Renbao

    2004-01-01

    Previously, we constructed DNA vectors containing cDNA of Mac-1 subunits (CD11b or CD18b) fused with fluorescence protein (FP). cDNA fragments and the DNA constructs were then transfected into CHO cells (as CHO-Mac-1-FP). The structure and function of Mac-1-FP obtained from the CHO-Mac-1-FP cells are nearly identical to that expressed in wild type leukocytes. In the present study, the intracellular trafficking of Mac-1 was visualized directly by monitoring the fluorescent intensities of YFP-CD18 and PE-conjugated monoclonal antibody against CD11b under a confocal microscope in CHO-Mac-1-FP cells. The results indicate that: (ⅰ) although Mac-1 was not detected in the cell membrane at resting state, it had been translocated and clustered into the cell membrane by 1 h and internalized 2 h after PMA stimulation, at which point the fluorescence intensity began to diminish gradually, probably due to partial degradation of Mac-1. The fluorescence of CD18 and CD11b reappeared on the cell membrane 1 h after re-treatment with PMA, suggesting the recycling of non-degraded Mac-1. (ⅱ) The adhesion rate of CHO-Mac-1-FP to magnetic beads coupled ICAM-1 increased within 4 h after their initial interaction, accompanied by the clustering of Mac-1-FP. After 8 h,the adhesion rate declined and fluorescence also decreased simultaneously. The pattern of change in fluorescence in CHO-Mac-1-FP cells elicited by ICAM-1 beads was similar to that elicited by PMA, suggesting that endocytosis and degradation of Mac-1 occurred after the interaction with ICAM-1. Thus, we conclude that the intracellular trafficking of Mac-1 after activation is associated with membrane translocation, endocytosis, degradation and recycling. These changes are in parallel with the adhesion of CHO-Mac-1-FP cells with ICAM-1, and may be involved in the adhesion and detachment of leukocytes. The detachment of leukocytes may be caused by endocytosis of Mac-1.

  20. An Energy Efficient Analysis of S-MAC And H-MAC Protocols for Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    P.T.Kalaivaani

    2013-04-01

    Full Text Available Wireless Sensor Networks (WSNs is an interesting topic to the researchers because of its variousapplications. The applications are health monitoring and environmental monitoring, Industrial ProcessMonitoring, Target detection, Target tracking, Energy Efficiency, Disaster Management and MilitarySecurity Systems. The wireless medium requires highly optimized medium Access Protocols to avoidinterferences. Limited resources have driven the research towards energy consumption of MACfunctionalities. Two Medium Access Control (MAC protocol performances are analyzed by using the MAClayer frame work for wireless sensor networks. In this paper an energy efficient analysis of S-MAC and HMACprotocols for wireless sensor networks is proposed with spatial correlation concept. Two MACprotocols such as Sensor MAC (S-MAC and Hybrid MAC (H-MAC protocols are proposed to analyze theperformance of Wireless Sensor Network using four different Parameters such as End to End delay, PacketDelivery Ratio, Packet Drop Rate and Energy Consumption. Performance analysis is carried out by usingthe simulation tool NS2.

  1. TreeMAC: Localized TDMA MAC protocol for real-time high-data-rate sensor networks

    Science.gov (United States)

    Song, W.-Z.; Huang, R.; Shirazi, B.; LaHusen, R.

    2009-01-01

    Earlier sensor network MAC protocols focus on energy conservation in low-duty cycle applications, while some recent applications involve real-time high-data-rate signals. This motivates us to design an innovative localized TDMA MAC protocol to achieve high throughput and low congestion in data collection sensor networks, besides energy conservation. TreeMAC divides a time cycle into frames and each frame into slots. A parent node determines the children's frame assignment based on their relative bandwidth demand, and each node calculates its own slot assignment based on its hop-count to the sink. This innovative 2-dimensional frame-slot assignment algorithm has the following nice theory properties. First, given any node, at any time slot, there is at most one active sender in its neighborhood (including itself). Second, the packet scheduling with TreeMAC is bufferless, which therefore minimizes the probability of network congestion. Third, the data throughput to the gateway is at least 1/3 of the optimum assuming reliable links. Our experiments on a 24-node testbed show that TreeMAC protocol significantly improves network throughput, fairness, and energy efficiency compared to TinyOS's default CSMA MAC protocol and a recent TDMA MAC protocol Funneling-MAC. Partial results of this paper were published in Song, Huang, Shirazi and Lahusen [W.-Z. Song, R. Huang, B. Shirazi, and R. Lahusen, TreeMAC: Localized TDMA MAC protocol for high-throughput and fairness in sensor networks, in: The 7th Annual IEEE International Conference on Pervasive Computing and Communications, PerCom, March 2009]. Our new contributions include analyses of the performance of TreeMAC from various aspects. We also present more implementation detail and evaluate TreeMAC from other aspects. ?? 2009 Elsevier B.V.

  2. 42 CFR 405.1122 - What evidence may be submitted to the MAC.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 2 2010-10-01 2010-10-01 false What evidence may be submitted to the MAC. 405.1122... Council Review § 405.1122 What evidence may be submitted to the MAC. (a) Appeal before the MAC on request for review of ALJ's decision. (1) If the MAC is reviewing an ALJ's decision, the MAC limits its review...

  3. 42 CFR 423.2122 - What evidence may be submitted to the MAC.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 3 2010-10-01 2010-10-01 false What evidence may be submitted to the MAC. 423.2122..., MAC review, and Judicial Review § 423.2122 What evidence may be submitted to the MAC. (a) Appeal before the MAC on request for review of ALJ's decision. (1) If the MAC is reviewing an ALJ's decision...

  4. Influence of prior determination of baseline minimum alveolar concentration (MAC) of isoflurane on the effect of ketamine on MAC in dogs.

    Science.gov (United States)

    Gianotti, Giacomo; Valverde, Alexander; Johnson, Ron; Sinclair, Melissa; Gibson, Thomas; Dyson, Doris H

    2014-07-01

    The objective of this study was to determine if prior measurement of the minimum alveolar concentration (MAC) of isoflurane influences the effect of ketamine on the MAC of isoflurane in dogs. Eight mixed-breed dogs were studied on 2 occasions. Anesthesia was induced and maintained using isoflurane. In group 1 the effect of ketamine on isoflurane MAC was determined after initially finding the baseline isoflurane MAC. In group 2, the effect of ketamine on isoflurane MAC was determined without previous measure of the baseline isoflurane MAC. In both groups, MAC was determined again 30 min after stopping the CRI of ketamine. Plasma ketamine concentrations were measured during MAC determinations. In group 1, baseline MAC (mean ± SD: 1.18 ± 0.14%) was decreased by ketamine (0.88 ± 0.14%; P MAC after stopping ketamine was similar (1.09 ± 0.16%) to baseline MAC and higher than with ketamine (P MAC with ketamine (0.79 ± 0.11%) was also increased after stopping ketamine (1.10 ± 0.17%; P MAC values with ketamine were different between groups (P MAC determination. The MAC of isoflurane during the CRI of ketamine yielded different results when methods of same day (group-1) versus separate days (group-2) are used, despite similar plasma ketamine concentrations with both methods. However, because the magnitude of this difference was less than 10%, either method of determining MAC is deemed acceptable for research purposes.

  5. On the orthogonality of the MacDonald s functions

    Energy Technology Data Exchange (ETDEWEB)

    Passian, Ali [ORNL; Simpson, Henry [University of Tennessee, Knoxville (UTK); Koucheckian, Sherwin [University of South Florida, Tampa; Yakubovich, Semyon [University of Porto, Portugal

    2009-01-01

    A proof of an orthogonality relation for the MacDonald's functions with identical arguments but unequal complex lower indices is presented. The orthogonality is derived first via a heuristic approach based on the Mehler-Fock integral transform of the MacDonald's functions, and then proved rigorously using a polynomial approximation procedure.

  6. SuperMacLang: Development of an Authoring System.

    Science.gov (United States)

    Frommer, Judith; Foelsche, Otmar K. E.

    1999-01-01

    Describes the development of "SuperMacLang, the 1990s version of the MacLang authoring system. An analysis of various features of the program explains the ways in which certain aspects of collaboration and funding affected developer and programming decisions. (Author/VWL)

  7. Steven MacCall: Winner of LJ's 2010 Teaching Award

    Science.gov (United States)

    Berry, John N., III

    2010-01-01

    This article profiles Steven L. MacCall, winner of "Library Journal's" 2010 Teaching Award. An associate professor at the School of Library and Information Studies (SLIS) at the University of Alabama, Tuscaloosa, MacCall was nominated by Kathie Popadin, known as "Kpop" to the members of her cohort in the online MLIS program at SLIS. Sixteen of…

  8. MAC of xenon and halothane in rhesus monkeys.

    Science.gov (United States)

    Whitehurst, S L; Nemoto, E M; Yao, L; Yonas, H

    1994-10-01

    Local cerebral blood flow (LCBF) maps produced by 33% xenon-enhanced computed tomographic scanning (Xe/CT LCBF) are useful in the clinical diagnosis and management of patients with cerebrovascular disorders. However, observations in humans that 25-35% xenon (Xe) inhalation increases cerebral blood flow (CBF) have raised concerns that Xe/CT LCBF measurements may be inaccurate and that Xe inhalation may be hazardous in patients with decreased intracranial compliance. In contrast, 33% Xe does not increase CBF in rhesus monkeys. To determine whether this interspecies difference in the effect of Xe on CBF correlates with an interspecies difference in the anesthetic potency of Xe, we measured the minimum alveolar concentration (MAC) of Xe preventing movement to a tail-clamp stimulus in rhesus monkeys. Using a standard protocol for the determination of MAC in animals, we first measured the MAC of halothane (n = 5), and then used a combination of halothane and Xe to measure the MAC of Xe (n = 7). The halothane MAC was 0.99 +/- 0.12% (M +/- SD), and the Xe MAC was 98 +/- 15%. These results suggest that the MAC of Xe in rhesus monkeys is higher than the reported human Xe MAC value of 71%. Thus the absence of an effect of 33% Xe on CBF in the rhesus monkey may be related to its lower anesthetic potency.

  9. Intel-Based Mac Computers Improve Teaching and Learning

    Science.gov (United States)

    Technology & Learning, 2007

    2007-01-01

    Today, Mac computers offer schools an easy and powerful way to engage students in learning, foster 21st century skills and leverage existing software assets. Innovative software and hardware built into the Mac allows students to demonstrate their individual strengths--empowering them to be creators of content, rather than just consumers. Judging…

  10. Intel-Based Mac Computers Improve Teaching and Learning

    Science.gov (United States)

    Technology & Learning, 2007

    2007-01-01

    Today, Mac computers offer schools an easy and powerful way to engage students in learning, foster 21st century skills and leverage existing software assets. Innovative software and hardware built into the Mac allows students to demonstrate their individual strengths--empowering them to be creators of content, rather than just consumers. Judging…

  11. Multi-channel MAC Protocol in Cognitive Radio Networks

    Directory of Open Access Journals (Sweden)

    Yongli Sun

    2013-11-01

    Full Text Available Since cognitive wireless network (CRN has the characteristic of secondary use, it can enable the device to dynamically access available spectrum without interference to primary users (PUs, which can effectively alleviate contradiction between the lack of spectrum resources and the growing demand for wireless access. However, Medium Access Control (MAC protocol as CRN core components, can achieve competition access of the licensed spectrum and coordination control, which will maximize spectrum utilization efficiency and network throughput. The contribution of this survey is threefold. First, we analyze the characteristics of the existed multi- channel MAC protocol in CRN; Second, according to the different ways of spectrum access in CRNs, the multi-channel MAC protocols are classified into time-slotted based MAC protocol, control channel based MAC protocol and hybrid MAC protocol, and the paper emphatically analyzed the advantages and disadvantages of these multi-channel MAC protocols; Finally, the paper explores the difficulties and the challenges of multi-channel MAC protocols design in cognitive wireless network.

  12. Steven MacCall: Winner of LJ's 2010 Teaching Award

    Science.gov (United States)

    Berry, John N., III

    2010-01-01

    This article profiles Steven L. MacCall, winner of "Library Journal's" 2010 Teaching Award. An associate professor at the School of Library and Information Studies (SLIS) at the University of Alabama, Tuscaloosa, MacCall was nominated by Kathie Popadin, known as "Kpop" to the members of her cohort in the online MLIS program at SLIS. Sixteen of…

  13. Evaluation of Integrated Routing/MAC Solutions for the Diffusion of Warning Messages in VANETs

    Directory of Open Access Journals (Sweden)

    Luca Campelli

    2007-12-01

    Full Text Available The efficiency of routing protocols in general mobile ad hoc networks may be highly affected by the specific Medium Access Control scheme the routing relies upon and by the mobility of the wireless nodes. In this work, we address the design of position based routing solutions for the support of safety oriented applications in Vehicular Ad hoc NETworks (VANETs by focusing on the impact of the MAC layer on the performances of the routing strategies. Namely, we propose a simulation analysis in highway scenarios to assess the routing performance in the two cases where standard IEEE 802.11 technology and a dynamic TDMA scheme are adopted at layer 2 respectively. We discuss on the dimensioning of the routing parameters in both cases and we provide a comparative analysis of the two MAC/routing integrated solutions.

  14. A Sensing Error Aware MAC Protocol for Cognitive Radio Networks

    CERN Document Server

    Hu, Donglin

    2011-01-01

    Cognitive radios (CR) are intelligent radio devices that can sense the radio environment and adapt to changes in the radio environment. Spectrum sensing and spectrum access are the two key CR functions. In this paper, we present a spectrum sensing error aware MAC protocol for a CR network collocated with multiple primary networks. We explicitly consider both types of sensing errors in the CR MAC design, since such errors are inevitable for practical spectrum sensors and more important, such errors could have significant impact on the performance of the CR MAC protocol. Two spectrum sensing polices are presented, with which secondary users collaboratively sense the licensed channels. The sensing policies are then incorporated into p-Persistent CSMA to coordinate opportunistic spectrum access for CR network users. We present an analysis of the interference and throughput performance of the proposed CR MAC, and find the analysis highly accurate in our simulation studies. The proposed sensing error aware CR MAC p...

  15. McCay ("Mac") Vernon (1928-2013).

    Science.gov (United States)

    Sherman, William A

    2014-09-01

    McCay ("Mac") Vernon, the founding and preeminent psychologist in the field of deafness. Mac was born at Walter Reed Hospital in Washington, DC, into a military family on October 14, 1928 and died on August 28, 2013, at the age of 84. Prior to Mac, research and clinical direction in the field were sparse. Mac became the icon for psychological services for deaf people, and his work extended into the education of deaf children, forensic and ethical practices with the deaf, and public understanding of deafness as a disability and of deaf persons as a psychosocial minority group. Mac will also be remembered for his sharp intellect, good humor, compassion, and advocacy for those who are misunderstood.

  16. Alasdair MacIntyre, joven lector de Freud

    Directory of Open Access Journals (Sweden)

    Ramis Barceló, Rafael

    2010-06-01

    Full Text Available This article tries to show the reading of Freud that MacIntyre made from 1955 to 1970. For this purpose, it summarizes the ideas of MacIntyre in the intellectual context, mainly the use of philosophical ideas of Freud against the Enlightenment project. MacIntyre criticises Marxist interpreters and the mixing between Marx and Freud. MacIntyre uses the philosophical ideas of Freud for answering two problems on determinism: the links between determinism and reasons for action and determinism and Marxism. The main conclusion is that MacIntyre used Freud in his own advantage: as an ally in the criticism of the Enlightenment.

    Este artículo trata de mostrar la lectura que MacIntyre hizo de Freud desde 1955 hasta 1970. Con este fin, se resumen las ideas de MacIntyre en el contexto intelectual, principalmente el uso de las ideas filosóficas de Freud contra el proyecto de la Ilustración. MacIntyre critica a los intérpretes de Marx y a la mezcla entre Marx y Freud. MacIntyre usa las ideas filosóficas de Freud para contestar dos problemas sobre el determinismo: los vínculos entre el determinismo y las razones para la acción y el determinismo y el marxismo. La conclusión principal es que MacIntyre usó a Freud en su propio beneficio: como un aliado en la crítica de la Ilustración.

  17. Optimal filtering

    CERN Document Server

    Anderson, Brian D O

    2005-01-01

    This graduate-level text augments and extends beyond undergraduate studies of signal processing, particularly in regard to communication systems and digital filtering theory. Vital for students in the fields of control and communications, its contents are also relevant to students in such diverse areas as statistics, economics, bioengineering, and operations research.Topics include filtering, linear systems, and estimation; the discrete-time Kalman filter; time-invariant filters; properties of Kalman filters; computational aspects; and smoothing of discrete-time signals. Additional subjects e

  18. TreeMAC: Localized TDMA MAC protocol for real-time high-data-rate sensor networks

    Science.gov (United States)

    Song, W.-Z.; Huang, R.; Shirazi, B.; Husent, R.L.

    2009-01-01

    Earlier sensor network MAC protocols focus on energy conservation in low-duty cycle applications, while some recent applications involve real-time high-data-rate signals. This motivates us to design an innovative localized TDMA MAC protocol to achieve high throughput and low congestion in data collection sensor networks, besides energy conservation. TreeMAC divides a time cycle into frames and frame into slots. Parent determines children's frame assigmnent based on their relative bandwidth demand, and each node calculates its own slot assignment based on its hop-count to the sink. This innovative 2-dimensional frame-slot assignment algorithm has the following nice theory properties. Firstly, given any node, at any time slot, there is at most one active sender in its neighborhood (includ ing itself). Secondly, the packet scheduling with TreelMAC is bufferless, which therefore minimizes the probability of network congestion. Thirdly, the data throughput to gateway is at least 1/3 of the optimum assuming reliable links. Our experiments on a 24 node test bed demonstrate that TreeMAC protocol significantly improves network throughput and energy efficiency, by comparing to the TinyOS's default CSMA MAC protocol and a recent TDMA MAC protocol Funneling-MAC[8]. ?? 2009 IEEE.

  19. TR-MAC: an energy-efficient MAC protocol exploiting transmitted reference modulation for wireless sensor networks

    NARCIS (Netherlands)

    Morshed, S.; Heijenk, Geert

    2014-01-01

    The medium access control (MAC) protocol determines the energy consumption of a wireless sensor node by specifying the listening, transmitting or sleeping time. Therefore MAC protocols play an important role in minimizing the overall energy consumption in a typical wireless sensor network (WSN).

  20. TR-MAC: an energy-efficient MAC protocol exploiting transmitted reference modulation for wireless sensor networks

    NARCIS (Netherlands)

    Morshed, Sarwar; Heijenk, Geert

    2014-01-01

    The medium access control (MAC) protocol determines the energy consumption of a wireless sensor node by specifying the listening, transmitting or sleeping time. Therefore MAC protocols play an important role in minimizing the overall energy consumption in a typical wireless sensor network (WSN). Usi

  1. Updating the OMERACT filter

    DEFF Research Database (Denmark)

    Tugwell, Peter; Boers, Maarten; D'Agostino, Maria-Antonietta

    2014-01-01

    OBJECTIVE: The Outcome Measures in Rheumatology (OMERACT) Filter provides guidelines for the development and validation of outcome measures for use in clinical research. The "Truth" section of the OMERACT Filter requires that criteria be met to demonstrate that the outcome instrument meets...... the criteria for content, face, and construct validity. METHODS: Discussion groups critically reviewed a variety of ways in which case studies of current OMERACT Working Groups complied with the Truth component of the Filter and what issues remained to be resolved. RESULTS: The case studies showed...... that there is broad agreement on criteria for meeting the Truth criteria through demonstration of content, face, and construct validity; however, several issues were identified that the Filter Working Group will need to address. CONCLUSION: These issues will require resolution to reach consensus on how Truth...

  2. Integrated Spatial Filter Array Project

    Data.gov (United States)

    National Aeronautics and Space Administration — To address the NASA Earth Science Division need for spatial filter arrays for amplitude and wavefront control, Luminit proposes to develop a novel Integrated Spatial...

  3. The minimum alveolar concentration (MAC) of isoflurane in preterm neonates.

    Science.gov (United States)

    LeDez, K M; Lerman, J

    1987-09-01

    Studies in fetal lambs suggested that the minimum alveolar concentration (MAC) in preterm neonates may be less than that in full-term neonates and older infants. To determine the MAC of isoflurane in preterm neonates, 20 patients less than 32 weeks gestation at birth and 16 patients 32-37 weeks gestation at birth, all less than 1 month post-natal age, were studied. Following tracheal intubation, the neonates were anesthetized with a predetermined end-tidal concentration of isoflurane in oxygen and air. The move-no move responses to skin incision were recorded, and MAC was determined using the "up-and-down" technique. Heart rate and systolic arterial pressure were recorded awake, before skin incision, and after skin incision. MAC (mean +/- SD) of isoflurane in preterm neonates less than 32 weeks gestation was 1.28 +/- 0.17%, and MAC in neonates 32-37 weeks gestation was 1.41 +/- 0.18% (P less than 0.05). Although heart rate did not decrease significantly in either group during the study, systolic arterial pressure decreased between 20 and 30% below awake values both before and after skin incision in both age groups (P less than 0.01). We conclude that the MAC of isoflurane in preterm neonates less than 32 weeks gestation is significantly less than that in preterm neonates 32-37 weeks gestation, and that systolic arterial pressure decreases to a similar extent at approximately 1 MAC isoflurane in both age groups.

  4. Increased NMDA receptor inhibition at an increased Sevoflurane MAC

    Directory of Open Access Journals (Sweden)

    Brosnan Robert J

    2012-06-01

    Full Text Available Abstract Background Sevoflurane potently enhances glycine receptor currents and more modestly decreases NMDA receptor currents, each of which may contribute to immobility. This modest NMDA receptor antagonism by sevoflurane at a minimum alveolar concentration (MAC could be reciprocally related to large potentiation of other inhibitory ion channels. If so, then reduced glycine receptor potency should increase NMDA receptor antagonism by sevoflurane at MAC. Methods Indwelling lumbar subarachnoid catheters were surgically placed in 14 anesthetized rats. Rats were anesthetized with sevoflurane the next day, and a pre-infusion sevoflurane MAC was measured in duplicate using a tail clamp method. Artificial CSF (aCSF containing either 0 or 4 mg/mL strychnine was then infused intrathecally at 4 μL/min, and the post-infusion baseline sevoflurane MAC was measured. Finally, aCSF containing strychnine (either 0 or 4 mg/mL plus 0.4 mg/mL dizocilpine (MK-801 was administered intrathecally at 4 μL/min, and the post-dizocilpine sevoflurane MAC was measured. Results Pre-infusion sevoflurane MAC was 2.26%. Intrathecal aCSF alone did not affect MAC, but intrathecal strychnine significantly increased sevoflurane requirement. Addition of dizocilpine significantly decreased MAC in all rats, but this decrease was two times larger in rats without intrathecal strychnine compared to rats with intrathecal strychnine, a statistically significant (P  Conclusions Glycine receptor antagonism increases NMDA receptor antagonism by sevoflurane at MAC. The magnitude of anesthetic effects on a given ion channel may therefore depend on the magnitude of its effects on other receptors that modulate neuronal excitability.

  5. Increased NMDA receptor inhibition at an increased Sevoflurane MAC.

    Science.gov (United States)

    Brosnan, Robert J; Thiesen, Roberto

    2012-06-06

    Sevoflurane potently enhances glycine receptor currents and more modestly decreases NMDA receptor currents, each of which may contribute to immobility. This modest NMDA receptor antagonism by sevoflurane at a minimum alveolar concentration (MAC) could be reciprocally related to large potentiation of other inhibitory ion channels. If so, then reduced glycine receptor potency should increase NMDA receptor antagonism by sevoflurane at MAC. Indwelling lumbar subarachnoid catheters were surgically placed in 14 anesthetized rats. Rats were anesthetized with sevoflurane the next day, and a pre-infusion sevoflurane MAC was measured in duplicate using a tail clamp method. Artificial CSF (aCSF) containing either 0 or 4 mg/mL strychnine was then infused intrathecally at 4 μL/min, and the post-infusion baseline sevoflurane MAC was measured. Finally, aCSF containing strychnine (either 0 or 4 mg/mL) plus 0.4 mg/mL dizocilpine (MK-801) was administered intrathecally at 4 μL/min, and the post-dizocilpine sevoflurane MAC was measured. Pre-infusion sevoflurane MAC was 2.26%. Intrathecal aCSF alone did not affect MAC, but intrathecal strychnine significantly increased sevoflurane requirement. Addition of dizocilpine significantly decreased MAC in all rats, but this decrease was two times larger in rats without intrathecal strychnine compared to rats with intrathecal strychnine, a statistically significant (P MAC. The magnitude of anesthetic effects on a given ion channel may therefore depend on the magnitude of its effects on other receptors that modulate neuronal excitability.

  6. Multichannel MAC Layer In Mobile Ad—Hoc Network

    Science.gov (United States)

    Logesh, K.; Rao, Samba Siva

    2010-11-01

    This paper we presented the design objectives and technical challenges in Multichannel MAC protocols in Mobile Ad-hoc Network. In IEEE 802.11 a/b/g standards allow use of multiple channels, only a single channel is popularly used, due to the lack of efficient protocols that enable use of Multiple Channels. Even though complex environments in ad hoc networks require a combined control of physical (PHY) and medium access control (MAC) layers resources in order to optimize performance. And also we discuss the characteristics of cross-layer frame and give a multichannel MAC approach.

  7. MacRuby Ruby and Cocoa on OS X

    CERN Document Server

    Aimonetti, Matt

    2011-01-01

    Want to build native Mac OS X applications with a sleek, developer-friendly alternative to Objective-C? MacRuby is an ideal choice. This in-depth guide shows you how Apple's implementation of Ruby gives you access to all the features available to Objective-C programmers. You'll get clear, detailed explanations of MacRuby, including quick programming techniques such as prototyping. Perfect for programmers at any level, this book is packed with code samples and complete project examples. If you use Ruby, you can tap your skills to take advantage of Interface Builder, Cocoa libraries, the Objec

  8. Handling Deafness Problem of Scheduled Multi-Channel Polling MACs

    Science.gov (United States)

    Jiang, Fulong; Liu, Hao; Shi, Longxing

    Combining scheduled channel polling with channel diversity is a promising way for a MAC protocol to achieve high energy efficiency and performance under both light and heavy traffic conditions. However, the deafness problem may cancel out the benefit of channel diversity. In this paper, we first investigate the deafness problem of scheduled multi-channel polling MACs with experiments. Then we propose and evaluate two schemes to handle the deafness problem. Our experiment shows that deafness is a significant reason for performance degradation in scheduled multi-channel polling MACs. A proper scheme should be chosen depending on the traffic pattern and the design objective.

  9. Cooperative energy harvesting-adaptive MAC protocol for WBANs.

    Science.gov (United States)

    Esteves, Volker; Antonopoulos, Angelos; Kartsakli, Elli; Puig-Vidal, Manel; Miribel-Català, Pere; Verikoukis, Christos

    2015-05-28

    In this paper, we introduce a cooperative medium access control (MAC) protocol, named cooperative energy harvesting (CEH)-MAC, that adapts its operation to the energy harvesting (EH) conditions in wireless body area networks (WBANs). In particular, the proposed protocol exploits the EH information in order to set an idle time that allows the relay nodes to charge their batteries and complete the cooperation phase successfully. Extensive simulations have shown that CEH-MAC significantly improves the network performance in terms of throughput, delay and energy efficiency compared to the cooperative operation of the baseline IEEE 802.15.6 standard.

  10. A Hybrid MacCormack-type Scheme for Computational Aeroacoustics

    Science.gov (United States)

    Yazdani, Soroush

    A new type of MacCormack scheme, using a modified Low Dissipation and Dispersion Runge-Kutta time marching method, is presented. This scheme is using two stages in every step which implements biased spatial differencing stencils and for the remaining stages uses non-dissipative central differencing stencils. Because of using the MacCormack-type scheme in this method, the new scheme carries an inherent artificial dissipation which uses the ease of implementing boundary condition specifications of a two-stage MacCormack scheme.

  11. iMac G3 Blueberry 350MHz

    CERN Multimedia

    2000-01-01

    The iMac G3 is an all-in-one personal computer, encompassing both the monitor and the computer in one package. It allowed to revitalize the Apple brand that was in decline and close to financial ruin. Originally released in striking bondi blue and later a range of other translucent plastic envelopes in bright colors. The iMac comes with a keyboard and mouse matching the color of the case. The iMac G3 was sold from 1998 to 2003 and has been updated many times.

  12. Intelligent Local Avoided Collision (iLAC) MAC Protocol for Very High Speed Wireless Network

    Science.gov (United States)

    Hieu, Dinh Chi; Masuda, Akeo; Rabarijaona, Verotiana Hanitriniala; Shimamoto, Shigeru

    Future wireless communication systems aim at very high data rates. As the medium access control (MAC) protocol plays the central role in determining the overall performance of the wireless system, designing a suitable MAC protocol is critical to fully exploit the benefit of high speed transmission that the physical layer (PHY) offers. In the latest 802.11n standard [2], the problem of long overhead has been addressed adequately but the issue of excessive colliding transmissions, especially in congested situation, remains untouched. The procedure of setting the backoff value is the heart of the 802.11 distributed coordination function (DCF) to avoid collision in which each station makes its own decision on how to avoid collision in the next transmission. However, collision avoidance is a problem that can not be solved by a single station. In this paper, we introduce a new MAC protocol called Intelligent Local Avoided Collision (iLAC) that redefines individual rationality in choosing the backoff counter value to avoid a colliding transmission. The distinguishing feature of iLAC is that it fundamentally changes this decision making process from collision avoidance to collaborative collision prevention. As a result, stations can avoid colliding transmissions with much greater precision. Analytical solution confirms the validity of this proposal and simulation results show that the proposed algorithm outperforms the conventional algorithms by a large margin.

  13. PAD-MAC: primary user activity-aware distributed MAC for multi-channel cognitive radio networks.

    Science.gov (United States)

    Ali, Amjad; Piran, Md Jalil; Kim, Hansoo; Yun, Jihyeok; Suh, Doug Young

    2015-03-30

    Cognitive radio (CR) has emerged as a promising technology to solve problems related to spectrum scarcity and provides a ubiquitous wireless access environment. CR-enabled secondary users (SUs) exploit spectrum white spaces opportunistically and immediately vacate the acquired licensed channels as primary users (PUs) arrive. Accessing the licensed channels without the prior knowledge of PU traffic patterns causes severe throughput degradation due to excessive channel switching and PU-to-SU collisions. Therefore, it is significantly important to design a PU activity-aware medium access control (MAC) protocol for cognitive radio networks (CRNs). In this paper, we first propose a licensed channel usage pattern identification scheme, based on a two-state Markov model, and then estimate the future idle slots using previous observations of the channels. Furthermore, based on these past observations, we compute the rank of each available licensed channel that gives SU transmission success assessment during the estimated idle slot. Secondly, we propose a PU activity-aware distributed MAC (PAD-MAC) protocol for heterogeneous multi-channel CRNs that selects the best channel for each SU to enhance its throughput. PAD-MAC controls SU activities by allowing them to exploit the licensed channels only for the duration of estimated idle slots and enables predictive and fast channel switching. To evaluate the performance of the proposed PAD-MAC, we compare it with the distributed QoS-aware MAC (QC-MAC) and listen-before-talk MAC schemes. Extensive numerical results show the significant improvements of the PAD-MAC in terms of the SU throughput, SU channel switching rate and PU-to-SU collision rate.

  14. Infecting Windows, Linux & Mac in one go

    CERN Multimedia

    Computer Security Team

    2012-01-01

    Still love bashing on Windows as you believe it is an insecure operating system? Hold on a second! Just recently, a vulnerability has been published for Java 7.   It affects Windows/Linux PCs and Macs, Internet Explorer, Safari and Firefox. In fact, it affects all computers that have enabled the Java 7 plug-in in their browser (Java 6 and earlier is not affected). Once you visit a malicious website (and there are plenty already out in the wild), your computer is infected… That's "Game Over" for you.      And this is not the first time. For a while now, attackers have not been targeting the operating system itself, but rather aiming at vulnerabilities inherent in e.g. your Acrobat Reader, Adobe Flash or Java programmes. All these are standard plug-ins added into your favourite web browser which make your web-surfing comfortable (or impossible when you un-install them). A single compromised web-site, however, is sufficient to prob...

  15. Prior determination of baseline minimum alveolar concentration (MAC) of isoflurane does not influence the effect of ketamine on MAC in rabbits.

    Science.gov (United States)

    Gianotti, Giacomo; Valverde, Alexander; Sinclair, Melissa; Dyson, Doris H; Gibson, Thomas; Johnson, Ron

    2012-10-01

    The objective of this study was to compare the effect on the minimum alveolar concentration (MAC) of isoflurane when ketamine was administered either after or without prior determination of the baseline MAC of isoflurane in rabbits. Using a prospective randomized crossover study, 8 adult, female New Zealand rabbits were allocated to 2 treatment groups. Anesthesia was induced and maintained with isoflurane. Group 1 (same-day determination) had the MAC-sparing effect of ketamine [1 mg/kg bodyweight (BW) bolus followed by a constant rate infusion (CRI) of 40 μg/kg BW per min, given by intravenous (IV)], which was determined after the baseline MAC of isoflurane was determined beforehand. A third MAC determination was started 30 min after stopping the CRI. Group 2 (separate-day determination) had the MAC-sparing effect of ketamine determined without previous determination of the baseline MAC of isoflurane. A second MAC determination was started 30 min after stopping the CRI. In group 1, the MAC of isoflurane (2.15 ± 0.09%) was significantly decreased by ketamine (1.63 ± 0.07%). After stopping the CRI, the MAC was significantly less (2.04 ± 0.11%) than the baseline MAC of isoflurane and significantly greater than the MAC during the CRI. In group 2, ketamine decreased isoflurane MAC (1.53 ± 0.22%) and the MAC increased significantly (1.94 ± 0.25%) after stopping the CRI. Minimum alveolar concentration (MAC) values did not differ significantly between the groups either during ketamine administration or after stopping ketamine. Under the study conditions, prior determination of the baseline isoflurane MAC did not alter the effect of ketamine on MAC. Both methods of determining MAC seemed to be valid for research purposes.

  16. Microfabricated inserts for magic angle coil spinning (MACS wireless NMR spectroscopy.

    Directory of Open Access Journals (Sweden)

    Vlad Badilita

    Full Text Available This article describes the development and testing of the first automatically microfabricated probes to be used in conjunction with the magic angle coil spinning (MACS NMR technique. NMR spectroscopy is a versatile technique for a large range of applications, but its intrinsically low sensitivity poses significant difficulties in analyzing mass- and volume-limited samples. The combination of microfabrication technology and MACS addresses several well-known NMR issues in a concerted manner for the first time: (i reproducible wafer-scale fabrication of the first-in-kind on-chip LC microresonator for inductive coupling of the NMR signal and reliable exploitation of MACS capabilities; (ii improving the sensitivity and the spectral resolution by simultaneous spinning the detection microcoil together with the sample at the "magic angle" of 54.74° with respect to the direction of the magnetic field (magic angle spinning - MAS, accompanied by the wireless signal transmission between the microcoil and the primary circuit of the NMR spectrometer; (iii given the high spinning rates (tens of kHz involved in the MAS methodology, the microfabricated inserts exhibit a clear kinematic advantage over their previously demonstrated counterparts due to the inherent capability to produce small radius cylindrical geometries, thus tremendously reducing the mechanical stress and tearing forces on the sample. In order to demonstrate the versatility of the microfabrication technology, we have designed MACS probes for various Larmor frequencies (194, 500 and 700 MHz testing several samples such as water, Drosophila pupae, adamantane solid and LiCl at different magic angle spinning speeds.

  17. Competition at the Wireless Sensor Network MAC Layer: Low Power Probing interfering with X-MAC

    Science.gov (United States)

    Zacharias, Sven; Newe, Thomas

    2011-08-01

    Wireless Sensor Networks (WSNs) combine sensors with computer networks and enable very dense, in-situ and live measurements of data over a large area. Since this emerging technology has the potential to be embedded almost everywhere for numberless applications, interference between different networks can become a serious issue. For most WSNs, it is assumed today that the network medium access is non-competitive. On the basis of X-MAC interfered by Low Power Probing, this paper shows the danger and the effects of different sensor networks communicating on a single wireless channel of the 2.4 GHz band, which is used by the IEEE 802.15.4 standard.

  18. After MacIntyre : Kaasaegsest vooruseetikast / Meego Remmel

    Index Scriptorium Estoniae

    Remmel, Meego

    2006-01-01

    Alasdair MacIntyre panus 20. sajandi eetikasse. Tema käsitlus vooruseetikast ja vooruseetilisest perspektiivist, mida on võimalik näha komplekselt, vaadeldes voorust, praktikat, narratiivi ja traditsiooni mõisteid

  19. After MacIntyre : Kaasaegsest vooruseetikast / Meego Remmel

    Index Scriptorium Estoniae

    Remmel, Meego

    2006-01-01

    Alasdair MacIntyre panus 20. sajandi eetikasse. Tema käsitlus vooruseetikast ja vooruseetilisest perspektiivist, mida on võimalik näha komplekselt, vaadeldes voorust, praktikat, narratiivi ja traditsiooni mõisteid

  20. Design and Implementation of an Efficient 64 bit MAC

    Directory of Open Access Journals (Sweden)

    Mohammad Shabber Hasan Khan

    2015-08-01

    Full Text Available The design of optimized 64 bit multiplier and accumulator (MAC unit is implemented in this paper. MAC unit plays major role in many of the digital signal processing (DSP applications. The MAC unit is designed with the combinations of multipliers and adders. In the proposed method MAC unit is implemented using Vedic multiplier and the adder is done with ripple carry adder .The components are reduced by implementing Vedic multiplier using the techniques of Vedic mathematics that have been modified to improve performance. a high speed processor depends significantly on the multiplier as it is one of the key hardware blocks in most digital signal processing systems as well as in general processors. The area is optimized effectively using Vedic multiplier .The total design implemented using Xilinx.

  1. Beamforming in Ad Hoc Networks: MAC Design and Performance Modeling

    National Research Council Canada - National Science Library

    Fakih, Khalil; Diouris, Jean-Francois; Andrieux, Guillaume

    2009-01-01

    .... Our proposition performs jointly channel estimation and radio resource sharing. We validate the fruitfulness of the proposed MAC and we evaluate the effects of the channel estimation on the network performance...

  2. Rating of new outlet structures for MacFarlane Reservoir

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Memorandum explaining the new work on the outlet structure at MacFarlane Reservoir. Flow measurements were taken at different staff gage elevations and this data is...

  3. Big Mac arvestab raha ostujõudu / Harli Uljas

    Index Scriptorium Estoniae

    Uljas, Harli

    2005-01-01

    The Economist võrdleb maailma valuutade suhestamiseks Big Mac'i burgeri hindu 120 riigis, kuna see meetod võimaldab saada ülevaate riikide elanikkonna tegelikust ostujõust. Tabel: Hamburgeri standard

  4. Big Mac arvestab raha ostujõudu / Harli Uljas

    Index Scriptorium Estoniae

    Uljas, Harli

    2005-01-01

    The Economist võrdleb maailma valuutade suhestamiseks Big Mac'i burgeri hindu 120 riigis, kuna see meetod võimaldab saada ülevaate riikide elanikkonna tegelikust ostujõust. Tabel: Hamburgeri standard

  5. MAC layer security issues in wireless mesh networks

    Science.gov (United States)

    Reddy, K. Ganesh; Thilagam, P. Santhi

    2016-03-01

    Wireless Mesh Networks (WMNs) have emerged as a promising technology for a broad range of applications due to their self-organizing, self-configuring and self-healing capability, in addition to their low cost and easy maintenance. Securing WMNs is more challenging and complex issue due to their inherent characteristics such as shared wireless medium, multi-hop and inter-network communication, highly dynamic network topology and decentralized architecture. These vulnerable features expose the WMNs to several types of attacks in MAC layer. The existing MAC layer standards and implementations are inadequate to secure these features and fail to provide comprehensive security solutions to protect both backbone and client mesh. Hence, there is a need for developing efficient, scalable and integrated security solutions for WMNs. In this paper, we classify the MAC layer attacks and analyze the existing countermeasures. Based on attacks classification and countermeasures analysis, we derive the research directions to enhance the MAC layer security for WMNs.

  6. Mac OS X : Tiger edition the missing manual

    CERN Document Server

    Pogue, David

    2005-01-01

    You can set your watch to it: As soon as Apple comes out with another version of Mac OS X, David Pogue hits the streets with another meticulous Missing Manual to cover it with a wealth of detail. The new Mac OS X 10.4, better known as Tiger, is faster than its predecessors, but nothing's too fast for Pogue and Mac OS X: The Missing Manual. There are many reasons why this is the most popular computer book of all time. With its hallmark objectivity, the Tiger Edition thoroughly explores the latest features to grace the Mac OS. Which ones work well and which do not? What should you look for? Th

  7. Ultraviolet filters.

    Science.gov (United States)

    Shaath, Nadim A

    2010-04-01

    The chemistry, photostability and mechanism of action of ultraviolet filters are reviewed. The worldwide regulatory status of the 55 approved ultraviolet filters and their optical properties are documented. The photostabilty of butyl methoxydibenzoyl methane (avobenzone) is considered and methods to stabilize it in cosmetic formulations are presented.

  8. A tribute to Lloyd D. MacLean.

    Science.gov (United States)

    Keith, Roger G

    2015-08-01

    Dr. Lloyd D. MacLean, long-time co-editor of the Canadian Journal of Surgery passed away earlier this year at the age of 90. In order to appreciate the contributions of Dr. MacLean to the journal, this commentary recognizes him as a humble surgeon–scientist who was one of — if not the — most outstanding Canadian ambassadors to academic surgery in North America.

  9. Conformal holonomy in MacDowell-Mansouri gravity

    Energy Technology Data Exchange (ETDEWEB)

    Reid, James A., E-mail: j.a.reid@abdn.ac.uk [SUPA Department of Physics, University of Aberdeen, Aberdeen, AB24 3UE (United Kingdom); Wang, Charles H.-T., E-mail: c.wang@abdn.ac.uk [SUPA Department of Physics, University of Aberdeen, Aberdeen, AB24 3UE (United Kingdom); STFC Rutherford Appleton Laboratory, Chilton, Didcot, Oxon, OX11 0QX (United Kingdom)

    2014-03-15

    The MacDowell-Mansouri formulation of general relativity is based on a gauge theory whose gauge algebra depends on the sign of the cosmological constant. In this article, we show that the gauge algebra is uniquely determined by the conformal structure of spacetime itself. Specifically, we show that in vacuum: the spacetime conformal holonomy algebra coincides with the MacDowell-Mansouri gauge algebra for both signs of the cosmological constant, in both Lorentzian and Euclidean metric signatures.

  10. Some Problems of Alasdair MacIntyre’s "Emotivism Thesis"

    OpenAIRE

    2016-01-01

    In this article Alasdair MacIntyre’s thesis concerning emotivist use of moral utterances in contemporary liberal societies is analysed. One tries to show that it needs further clarification since at least three elements of MacIntyre’s argument seem to pose certain problems; these are: ‘discussion halt’ as the source of emotivism, comprehensive doctrines as premises of respective arguments in liberal debates and the problem of incommensurability. These three problematic eleme...

  11. 42 CFR 423.2102 - Request for MAC review when ALJ issues decision or dismissal.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 3 2010-10-01 2010-10-01 false Request for MAC review when ALJ issues decision or... Reopening, ALJ Hearings, MAC review, and Judicial Review § 423.2102 Request for MAC review when ALJ issues decision or dismissal. (a)(1) An enrollee to the ALJ hearing may request a MAC review if the enrollee files...

  12. 42 CFR 423.2062 - Applicability of policies not binding on the ALJ and MAC.

    Science.gov (United States)

    2010-10-01

    ... and MAC. 423.2062 Section 423.2062 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT... BENEFIT Reopening, ALJ Hearings, MAC review, and Judicial Review § 423.2062 Applicability of policies not binding on the ALJ and MAC. (a) ALJs and the MAC are not bound by CMS program guidance, such as program...

  13. 42 CFR 423.2110 - MAC reviews on its own motion.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 3 2010-10-01 2010-10-01 false MAC reviews on its own motion. 423.2110 Section 423... (CONTINUED) MEDICARE PROGRAM VOLUNTARY MEDICARE PRESCRIPTION DRUG BENEFIT Reopening, ALJ Hearings, MAC review, and Judicial Review § 423.2110 MAC reviews on its own motion. (a) General rule. The MAC may decide on...

  14. 42 CFR 423.2050 - Removal of a hearing request from an ALJ to the MAC.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 3 2010-10-01 2010-10-01 false Removal of a hearing request from an ALJ to the MAC..., ALJ Hearings, MAC review, and Judicial Review § 423.2050 Removal of a hearing request from an ALJ to the MAC. If a request for hearing is pending before an ALJ, the MAC may assume responsibility for...

  15. 42 CFR 423.2108 - MAC Actions when request for review is filed.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 3 2010-10-01 2010-10-01 false MAC Actions when request for review is filed. 423... Hearings, MAC review, and Judicial Review § 423.2108 MAC Actions when request for review is filed. (a) General. Except as specified in paragraph (c) of this section, when an enrollee requests that the MAC...

  16. A Mac Protocol Implementation for Wireless Sensor Network

    Directory of Open Access Journals (Sweden)

    Jamila Bhar

    2015-01-01

    Full Text Available IEEE 802.15.4 is an important standard for Low Rate Wireless Personal Area Network (LRWPAN. The IEEE 802.15.4 presents a flexible MAC protocol that provides good efficiency for data transmission by adapting its parameters according to characteristics of different applications. In this research work, some restrictions of this standard are explained and an improvement of traffic efficiency by optimizing MAC layer is proposed. Implementation details for several blocks of communication system are carefully modeled. The protocol implementation is done using VHDL language. The analysis gives a full understanding of the behavior of the MAC protocol with regard to backoff delay, data loss probability, congestion probability, slot effectiveness, and traffic distribution for terminals. Two ideas are proposed and tested to improve efficiency of CSMA/CA mechanism for IEEE 802.15.4 MAC Layer. Primarily, we dynamically adjust the backoff exponent (BE according to queue level of each node. Secondly, we vary the number of consecutive clear channel assessment (CCA for packet transmission. We demonstrate also that slot compensation provided by the enhanced MAC protocol can greatly avoid unused slots. The results show the significant improvements expected by our approach among the IEEE 802.15.4 MAC standards. Synthesis results show also hardware performances of our proposed architecture.

  17. C-Band Airport Surface Communications System Standards Development. Phase II Final Report. Volume 1: Concepts of Use, Initial System Requirements, Architecture, and AeroMACS Design Considerations

    Science.gov (United States)

    Hall, Edward; Isaacs, James; Henriksen, Steve; Zelkin, Natalie

    2011-01-01

    This report is provided as part of ITT s NASA Glenn Research Center Aerospace Communication Systems Technical Support (ACSTS) contract NNC05CA85C, Task 7: New ATM Requirements-Future Communications, C-Band and L-Band Communications Standard Development and was based on direction provided by FAA project-level agreements for New ATM Requirements-Future Communications. Task 7 included two subtasks. Subtask 7-1 addressed C-band (5091- to 5150-MHz) airport surface data communications standards development, systems engineering, test bed and prototype development, and tests and demonstrations to establish operational capability for the Aeronautical Mobile Airport Communications System (AeroMACS). Subtask 7-2 focused on systems engineering and development support of the L-band digital aeronautical communications system (L-DACS). Subtask 7-1 consisted of two phases. Phase I included development of AeroMACS concepts of use, requirements, architecture, and initial high-level safety risk assessment. Phase II builds on Phase I results and is presented in two volumes. Volume I (this document) is devoted to concepts of use, system requirements, and architecture, including AeroMACS design considerations. Volume II describes an AeroMACS prototype evaluation and presents final AeroMACS recommendations. This report also describes airport categorization and channelization methodologies. The purposes of the airport categorization task were (1) to facilitate initial AeroMACS architecture designs and enable budgetary projections by creating a set of airport categories based on common airport characteristics and design objectives, and (2) to offer high-level guidance to potential AeroMACS technology and policy development sponsors and service providers. A channelization plan methodology was developed because a common global methodology is needed to assure seamless interoperability among diverse AeroMACS services potentially supplied by multiple service providers.

  18. C-Band Airport Surface Communications System Standards Development. Phase II Final Report. Volume 2: Test Bed Performance Evaluation and Final AeroMACS Recommendations

    Science.gov (United States)

    Hall, Edward; Magner, James

    2011-01-01

    This report is provided as part of ITT s NASA Glenn Research Center Aerospace Communication Systems Technical Support (ACSTS) contract NNC05CA85C, Task 7: New ATM Requirements-Future Communications, C-Band and L-Band Communications Standard Development and was based on direction provided by FAA project-level agreements for New ATM Requirements-Future Communications. Task 7 included two subtasks. Subtask 7-1 addressed C-band (5091- to 5150-MHz) airport surface data communications standards development, systems engineering, test bed and prototype development, and tests and demonstrations to establish operational capability for the Aeronautical Mobile Airport Communications System (AeroMACS). Subtask 7-2 focused on systems engineering and development support of the L-band digital aeronautical communications system (L-DACS). Subtask 7-1 consisted of two phases. Phase I included development of AeroMACS concepts of use, requirements, architecture, and initial high-level safety risk assessment. Phase II builds on Phase I results and is presented in two volumes. Volume I is devoted to concepts of use, system requirements, and architecture, including AeroMACS design considerations. Volume II (this document) describes an AeroMACS prototype evaluation and presents final AeroMACS recommendations. This report also describes airport categorization and channelization methodologies. The purposes of the airport categorization task were (1) to facilitate initial AeroMACS architecture designs and enable budgetary projections by creating a set of airport categories based on common airport characteristics and design objectives, and (2) to offer high-level guidance to potential AeroMACS technology and policy development sponsors and service providers. A channelization plan methodology was developed because a common global methodology is needed to assure seamless interoperability among diverse AeroMACS services potentially supplied by multiple service providers.

  19. Connectivity-Based Reliable Multicast MAC Protocol for IEEE 802.11 Wireless LANs

    Directory of Open Access Journals (Sweden)

    Woo-Yong Choi

    2009-01-01

    Full Text Available We propose the efficient reliable multicast MAC protocol based on the connectivity information among the recipients. Enhancing the BMMM (Batch Mode Multicast MAC protocol, the reliable multicast MAC protocol significantly reduces the RAK (Request for ACK frame transmissions in a reasonable computational time and enhances the MAC performance. By the analytical performance analysis, the throughputs of the BMMM protocol and our proposed MAC protocol are derived. Numerical examples show that our proposed MAC protocol increases the reliable multicast MAC performance for IEEE 802.11 wireless LANs.

  20. Anaesthesia with sevoflurane in pigeons: minimal anaesthetic concentration (MAC) determination and investigation of cardiorespiratory variables at 1 MAC.

    Science.gov (United States)

    Botman, J; Gabriel, F; Dugdale, A H A; Vandeweerd, J-M

    2016-05-28

    The objective of the study was to determine the minimal anaesthetic concentration (MAC) of sevoflurane (SEVO) in pigeons and investigate the effects of 1 MAC SEVO anaesthesia on cardiovascular and respiratory variables compared with the awake state. This is a prospective, experimental study. Animals were seven healthy adult pigeons. After acclimatisation to handling, heart rate (HR), heart rhythm, respiratory rate (fR), end-expired carbon dioxide tension (PE'CO2), inspired CO2 tension, indirect systolic arterial blood pressure (SAP) and cloacal temperature were measured to determine baseline, 'awake' values. Pigeons were then anaesthetised with SEVO and MAC was determined by the 'bracketing' method. The same variables were monitored during a 40 minute period at 1.0 MAC SEVO for each bird. Mean MAC was 3.0±0.6 per cent for SEVO. During maintenance of anaesthesia at 1.0 MAC, SAP decreased significantly (Pawake PE'CO2 values were unexpectedly low. Sinus arrhythmias were detected in two birds under SEVO anaesthesia. The times to tracheal intubation and to recovery were 2.5±0.7 and 6.4±1.7 minutes, respectively. Recovery was rapid and uneventful in all birds. In conclusion, SEVO is suitable for anaesthesia in pigeons. British Veterinary Association.

  1. Learning Unix for Mac OS X Tiger Unlock the Power of Unix

    CERN Document Server

    Taylor, Dave

    2005-01-01

    Thoroughly revised and updated for Mac OS X Tiger, this new edition introduces Mac users to the Terminal application and shows you how to navigate the command interface, explore hundreds of Unix applications that come with the Mac, and, most importantly, how to take advantage of both the Mac and Unix interfaces. If you want to master the command-line, this gentle guide to using Unix on Mac OS X Tiger is well worth its cover price

  2. Food Filter

    Institute of Scientific and Technical Information of China (English)

    履之

    1995-01-01

    A typical food-processing plant produces about 500,000 gallons of waste water daily. Laden with organic compounds, this water usually is evaporated or discharged into sewers.A better solution is to filter the water through

  3. C-MAC compared with direct laryngoscopy for intubation in patients with cervical spine immobilization: A manikin trial.

    Science.gov (United States)

    Smereka, Jacek; Ladny, Jerzy R; Naylor, Amanda; Ruetzler, Kurt; Szarpak, Lukasz

    2017-08-01

    The aim of this study was to compare C-MAC videolaryngoscopy with direct laryngoscopy for intubation in simulated cervical spine immobilization conditions. The study was designed as a prospective randomized crossover manikin trial. 70 paramedics with MAC and C-MAC on the first attempt (95.7% MAC vs. 100% C-MAC), with similar intubation times (16.5s MAC vs. 18s C-MAC). Scenario B: The results with C-MAC were significantly better than those with MAC (pMAC vs. 19 s C-MAC), success of the first intubation attempt (88.6% MAC vs. 100% C-MAC), Cormack-Lehane grade, POGO score, severity of dental compression, device difficulty score, and preferred airway device. Scenario C: The results with C-MAC were significantly better than those with MAC (pMAC vs. 100% C-MAC), overall success rate, intubation time (27 s MAC vs. 20.5 s C-MAC), Cormack-Lehane grade, POGO score, dental compression, device difficulty score and the preferred airway device. The C-MAC videolaryngoscope is an excellent alternative to the MAC laryngoscope for intubating manikins with cervical spine immobilization. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. Multilevel Mixture Kalman Filter

    Directory of Open Access Journals (Sweden)

    Xiaodong Wang

    2004-11-01

    Full Text Available The mixture Kalman filter is a general sequential Monte Carlo technique for conditional linear dynamic systems. It generates samples of some indicator variables recursively based on sequential importance sampling (SIS and integrates out the linear and Gaussian state variables conditioned on these indicators. Due to the marginalization process, the complexity of the mixture Kalman filter is quite high if the dimension of the indicator sampling space is high. In this paper, we address this difficulty by developing a new Monte Carlo sampling scheme, namely, the multilevel mixture Kalman filter. The basic idea is to make use of the multilevel or hierarchical structure of the space from which the indicator variables take values. That is, we draw samples in a multilevel fashion, beginning with sampling from the highest-level sampling space and then draw samples from the associate subspace of the newly drawn samples in a lower-level sampling space, until reaching the desired sampling space. Such a multilevel sampling scheme can be used in conjunction with the delayed estimation method, such as the delayed-sample method, resulting in delayed multilevel mixture Kalman filter. Examples in wireless communication, specifically the coherent and noncoherent 16-QAM over flat-fading channels, are provided to demonstrate the performance of the proposed multilevel mixture Kalman filter.

  5. Victor Bérard et la Macédoine

    Directory of Open Access Journals (Sweden)

    Ivan Savev

    2011-01-01

    Full Text Available Un helléniste convaincu, Victor Bérard, en vient, au début du XXe siècle à soutenir l’existence de « Macédoniens » et le slogan « la Macédoine aux Macédoniens”.Le Congrès de Berlin en 1878 avait laissé la Macédoine aux mains des Ottomans. La Grèce, la Serbie et la Bulgarie, parvenues à ses limites et prévoyant le retrait futur des Ottomans peaufinent les arguments linguistiques et historiques qui justifieront leurs revendications territoriales. Victor Bérard, un helléniste respecté et bon connaisseur de la région sud balkanique, effectue des enquêtes en Macédoine en 1896 et 1903 qu’il publie à Paris.Cette étude montre comment, dans le contexte de la propagande nationaliste des prétendants à la possession de la Macédoine, Victor Bérard en vient progressivement à affirmer qu’il existe une population autochtone, les Macédoniens. Il soutient leur programme pour la constitution d’une fédération ou confédération avec le slogan « la Macédoine aux Macédoniens » ce qui fait toute l’actualité de ses ouvrages.In 1878, the Congress of Berlin had left Macedonia in the hands of the Ottomans. Greece, Serbia and Bulgaria had reached its limits. Anticipating the Ottoman retreat, they polish language and historical arguments that will justify their territorial claims. Victor Bérard, a respected Hellenist and a good expert of the southern Balkans, is doing researches in Macedonia in 1896 and 1903. These will be later published in Paris.This study shows how, in the context of the nationalist propaganda build-up made by the candidates for the possession of Macedonia, Victor Bérard comes progressively to assert the existence of a native population: the Macedonians. He supports their program for the forming of a federation or confederation which slogan would be “Macedonia to Macedonians”. This makes his works very topical.

  6. Charcoal filter testing

    Energy Technology Data Exchange (ETDEWEB)

    Lyons, J. [Nuclear Regulatory Commission, Washington, DC (United States)

    1997-08-01

    In this very brief, informal presentation, a representative of the US Nuclear Regulatory Commission outlines some problems with charcoal filter testing procedures and actions being taken to correct the problems. Two primary concerns are addressed: (1) the process to find the test method is confusing, and (2) the requirements of the reference test procedures result in condensation on the charcoal and causes the test to fail. To address these problems, emergency technical specifications were processed for three nuclear plants. A generic or an administrative letter is proposed as a more permanent solution. 1 fig.

  7. The many faces of Mac-1 in autoimmune disease.

    Science.gov (United States)

    Rosetti, Florencia; Mayadas, Tanya N

    2016-01-01

    Mac-1 (CD11b/CD18) is a β2 integrin classically regarded as a pro-inflammatory molecule because of its ability to promote phagocyte cytotoxic functions and enhance the function of several effector molecules such as FcγR, uPAR, and CD14. Nevertheless, recent reports have revealed that Mac-1 also plays significant immunoregulatory roles, and genetic variants in ITGAM, the gene that encodes CD11b, confer risk for the autoimmune disease systemic lupus erythematosus (SLE). This has renewed interest in the physiological roles of this integrin and raised new questions on how its seemingly opposing biological functions may be regulated. Here, we provide an overview of the CD18 integrins and how their activation may be regulated as this may shed light on how the opposing roles of Mac-1 may be elicited. We then discuss studies that exemplify Mac-1's pro-inflammatory versus regulatory roles particularly in the context of IgG immune complex-mediated inflammation. This includes a detailed examination of molecular mechanisms that could explain the risk-conferring effect of rs1143679, a single nucleotide non-synonymous Mac-1 polymorphism associated with SLE.

  8. Behavioral Modeling of WSN MAC Layer Security Attacks: A Sequential UML Approach

    DEFF Research Database (Denmark)

    Pawar, Pranav M.; Nielsen, Rasmus Hjorth; Prasad, Neeli R.

    2012-01-01

    Wireless sensor networks (WSNs) are growing enormously and becoming increasingly attractive for a variety of application areas such as tele-health monitoring, industry monitoring, home automation and many more. The primary weakness shared by all wireless application and technologies is the vulner......Wireless sensor networks (WSNs) are growing enormously and becoming increasingly attractive for a variety of application areas such as tele-health monitoring, industry monitoring, home automation and many more. The primary weakness shared by all wireless application and technologies...... is the vulnerability to security attacks/threats. The performance and behavior of a WSN are vastly affected by such attacks. In order to be able to better address the vulnerabilities of WSNs in terms of security, it is important to understand the behavior of the attacks. This paper addresses the behavioral modeling...... of medium access control (MAC) security attacks in WSNs. The MAC layer is responsible for energy consumption, delay and channel utilization of the network and attacks on this layer can introduce significant degradation of the individual sensor nodes due to energy drain and in performance due to delays...

  9. Dynamics of toxic genotypes of Microcystis aeruginosa complex (MAC) through a wide freshwater to marine environmental gradient.

    Science.gov (United States)

    Martínez de la Escalera, Gabriela; Kruk, Carla; Segura, Angel M; Nogueira, Lucía; Alcántara, Ignacio; Piccini, Claudia

    2017-02-01

    Bloom-forming species belonging to Microcystis aeruginosa complex (MAC) are the most commonly reported worldwide. MAC blooms are composed by toxic and non-toxic genotypes and the environmental conditions favouring the dominance of toxic genotypes are still a matter of debate among the scientific community. In this study, we evaluated the distribution of toxic MAC genotypes along a seasonal cycle and over an environmental gradient spanning 800km, from a eutrophic freshwater reservoir in Río Uruguay to marine water in the outer limit of Río de la Plata. Abundance of four mcy genes, mcyB, mcyD, mcyE and mcyJ was determined by qPCR and used as a proxy of abundance of toxic MAC genotypes. All the mcy genes were detected through the seasonal cycle at all sampling sites, being systematically higher in the freshwater reservoir and decreasing towards the marine site. The highest toxic genotype abundance was found during the austral summer months. According to generalized linear regressions and random forest models, temperature and conductivity were the most relevant explanatory variables. This suggests that although toxic MAC genotypes grow optimally in freshwater, they are also able to tolerate the high-salinity and low temperature conditions found in estuarine and marine waters. This ability to resist harsh conditions impose a health risk and a management challenge. To our knowledge, this is the first report addressing several mcy genes in a broad gradient that includes a wide array of different environmental conditions. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. Dolphin natures, human virtues: MacIntyre and ethical naturalism.

    Science.gov (United States)

    Glackin, Shane Nicholas

    2008-09-01

    Can biological facts explain human morality? Aristotelian 'virtue' ethics has traditionally assumed so. In recent years Alasdair MacIntyre has reintroduced a form of Aristotle's 'metaphysical biology' into his ethics. He argues that the ethological study of dependence and rationality in other species--dolphins in particular--sheds light on how those same traits in the typical lives of humans give rise to the moral virtues. However, some goal-oriented dolphin behaviour appears both dependent and rational in the precise manner which impresses MacIntyre, yet anything but ethically 'virtuous'. More damningly, dolphin ethologists consistently refuse to evaluate such behaviour in the manner MacIntyre claims is appropriate to moral judgement. In light of this, I argue that virtues--insofar as they name a biological or ethological category--do not name a morally significant one.

  11. An Energy Efficient MAC Proto col for Linear WSNs

    Institute of Scientific and Technical Information of China (English)

    DAI Guoyong; MIAO Chunyu; YING Kezhen; WANG Kai; CHEN Qingzhang

    2015-01-01

    Wireless sensor networks (WSNs) have been employed as an ideal solution in many applications for data gathering in harsh environment. Energy consumption is a key issue in wireless sensor networks since nodes are often battery operated. Medium access control (MAC) pro-tocol plays an important role in energy efficiency in wire-less sensor networks because nodes’ access to the shared medium is coordinated by the MAC layer. An energy ef-ficient MAC protocol is designed for data gathering in linear wireless sensor networks. In order to enhance the performance, when a source node transmits data to the sink, proper relay nodes are selected for forwarding data according to the energy consumption factor and residual energy balance factor. Some simulation experiments are conducted and the results show that, the proposed proto-col provides better energy efficiency and long lifetime than the existing DMAC protocol.

  12. A Fair-Priority MAC design in Networked Control System

    Directory of Open Access Journals (Sweden)

    Hongjun Li

    2009-10-01

    Full Text Available Media Access Control (MAC protocols in Wireless Networked Control System (WNCS must minimize the radio energy costs in sensor nodes. Latency and throughput are also important design features for MAC protocols in the applications. But most of them cannot guarantee quality for real-time traffic. This paper studies the state of the art of current real-time MAC protocols, and then introduces a medium access control protocol and a improved protocol that provide multiple priority levels and hard real-time transmission. The channel is accessed by sensors according to their priorities. Sensors send frames in a round manner with same priority. The fairness between different priorities is provided. The channel access procedure is divided into two stages: broadcast period and transmission period. Simulation and experiment results indicate that our protocol provides high channel utilization and bounded delays for real-time communication and can be well applied in the many fields especially the dynamic wireless sensor networks.

  13. Implementation of MAC by using Modified Vedic Multiplier

    Directory of Open Access Journals (Sweden)

    Sreelekshmi M. S.

    2013-09-01

    Full Text Available Multiplier Accumulator Unit (MAC is a part of Digital Signal Processors. The speed of MAC depends on the speed of multiplier. So by using an efficient Vedic multiplier which excels in terms of speed, power and area, the performance of MAC can be increased. For this fast method of multiplication based on ancient Indian Vedic mathematics is proposed in this paper. Among various method of multiplication in Vedic mathematics, Urdhva Tiryagbhyam is used and the multiplication is for 32 X 32 bits. Urdhva Tiryagbhyam is a general multiplication formula applicable to all cases of multiplication. Adder used is Carry Look Ahead adder. The proposed design shows improvement over carry save adder.

  14. Cognitive MAC Protocols for General Primary Network Models

    CERN Document Server

    Mehanna, Omar; Gamal, Hesham El

    2009-01-01

    We consider the design of cognitive Medium Access Control (MAC) protocols enabling a secondary (unlicensed) transmitter-receiver pair to communicate over the idle periods of a set of primary (licensed) channels. More specifically, we propose cognitive MAC protocols optimized for both slotted and un-slotted primary networks. For the slotted structure, the objective is to maximize the secondary throughput while maintaining synchronization between the secondary pair and not causing interference to the primary network. Our investigations differentiate between two sensing scenarios. In the first, the secondary transmitter is capable of sensing all the primary channels, whereas it senses only a subset of the primary channels in the second scenario. In both cases, we propose blind MAC protocols that efficiently learn the statistics of the primary traffic on-line and asymptotically achieve the throughput obtained when prior knowledge of primary traffic statistics is available. For the un-slotted structure, the object...

  15. Synthesizing Existing CSMA and TDMA Based MAC Protocols for VANETs.

    Science.gov (United States)

    Huang, Jiawei; Li, Qi; Zhong, Shaohua; Liu, Lianhai; Zhong, Ping; Wang, Jianxin; Ye, Jin

    2017-02-10

    Many Carrier Sense Multiple Access (CSMA) and Time Division Multiple Access (TDMA) based medium access control (MAC) protocols for vehicular ad hoc networks (VANETs) have been proposed recently. Contrary to the common perception that they are competitors, we argue that the underlying strategies used in these MAC protocols are complementary. Based on this insight, we design CTMAC, a MAC protocol that synthesizes existing strategies; namely, random accessing channel (used in CSMA-style protocols) and arbitral reserving channel (used in TDMA-based protocols). CTMAC swiftly changes its strategy according to the vehicle density, and its performance is better than the state-of-the-art protocols. We evaluate CTMAC using at-scale simulations. Our results show that CTMAC reduces the channel completion time and increases the network goodput by 45% for a wide range of application workloads and network settings.

  16. ETEEM- Extended Traffic Aware Energy Efficient MAC Scheme for WSNs

    Directory of Open Access Journals (Sweden)

    Younas Khan

    2016-11-01

    Full Text Available Idle listening issue arises when a sensor node listens to medium despite the absence of data which results in consumption of energy. ETEEM is a variant of Traffic Aware Energy Efficient MAC protocol (TEEM which focuses on energy optimization due to reduced idle listening time and much lesser overhead on energy sources. It uses a novel scheme for using idle listening time of sensor nodes. The nodes are only active for small amount of time and most of the time, will be in sleep mode when no data is available. ETEEM reduces energy at byte level and uses a smaller byte packet called FLAG replacing longer byte SYNC packets of S-MAC and SYNCrts of TEEM respectively. It also uses a single acknowledgement packet per data set hence reducing energy while reducing frequency of the acknowledgment frames sent. The performance of ETEEM is 70% better comparative to other under-consideration MAC protocols.

  17. Office for iPad and Mac for dummies

    CERN Document Server

    Weverka, Peter

    2015-01-01

    The easy way to work with Office on your iPad or Mac Are you a Mac user who isn't accustomed to working with Microsoft Office? Consider this friendly guide your go-to reference! Written in plain English and packed with easy-to-follow, step-by-step instructions, Office for iPad and Mac For Dummies walks you through every facet of Office, from installing the software and opening files to working with Word, Excel, PowerPoint, and Outlook-and beyond. Plus, you'll discover how to manage files, share content and collaborate online through social media, and find help when you need it. Two things a

  18. Allegheny County Address Points

    Data.gov (United States)

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — This dataset contains address points which represent physical address locations assigned by the Allegheny County addressing authority. Data is updated by County...

  19. Allegheny County Address Points

    Data.gov (United States)

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — This dataset contains address points which represent physical address locations assigned by the Allegheny County addressing authority. Data is updated by County...

  20. AMPA receptor competitive antagonism reduces halothane MAC in rats.

    Science.gov (United States)

    McFarlane, C; Warner, D S; Todd, M M; Nordholm, L

    1992-12-01

    Various subtypes of receptors have been identified for glutamate, an excitatory neurotransmitter. Previous studies have shown that antagonism of glutamate at the NMDA receptors reduces minimum alveolar concentration (MAC) for volatile anesthetics. NBQX (2,3-dihydroxy-6-nitro-7-sulfamoyl-benzo(f)quinoxaline) is a selective antagonist at the glutamatergic AMPA receptor. The purpose of this experiment was to determine whether AMPA receptor antagonism influences halothane MAC in the rat. Sprague-Dawley rats were anesthetized with halothane in 50% O2/balance N2, tracheally intubated and the lungs were mechanically ventilated. Increasing doses of NBQX were intravenously infused in three groups while the control group was infused with vehicle (D5W). Halothane MAC was then determined by the tail-clamp method. Halothane MAC was log-linearly related to plasma NBQX concentrations (MAC = 0.125 (In plasma concentration NBQX) + 1.035, r2 = 0.77). A maximal 58% reduction of halothane MAC was achieved with an NBQX loading dose of 42 mg/kg followed by a continuous infusion rate of 36 mg x kg-1 x h-1 (control = 1.02 +/- 0.07%; NBQX = 0.43 +/- 0.12%; P awake rats were randomly assigned to groups based on the dose of NBQX infused. Pa(CO2) and mean arterial pressure were measured at time 0 and at 5 and 30 min after start of NBQX infusion. The infusion was then stopped. Time until recovery of the righting reflex was recorded.(ABSTRACT TRUNCATED AT 250 WORDS)

  1. Vehicle Health Management Communications Requirements for AeroMACS

    Science.gov (United States)

    Kerczewski, Robert J.; Clements, Donna J.; Apaza, Rafael D.

    2012-01-01

    As the development of standards for the aeronautical mobile airport communications system (AeroMACS) progresses, the process of identifying and quantifying appropriate uses for the system is progressing. In addition to defining important elements of AeroMACS standards, indentifying the systems uses impacts AeroMACS bandwidth requirements. Although an initial 59 MHz spectrum allocation for AeroMACS was established in 2007, the allocation may be inadequate; studies have indicated that 100 MHz or more of spectrum may be required to support airport surface communications. Hence additional spectrum allocations have been proposed. Vehicle health management (VHM) systems, which can produce large volumes of vehicle health data, were not considered in the original bandwidth requirements analyses, and are therefore of interest in supporting proposals for additional AeroMACS spectrum. VHM systems are an emerging development in air vehicle safety, and preliminary estimates of the amount of data that will be produced and transmitted off an aircraft, both in flight and on the ground, have been prepared based on estimates of data produced by on-board vehicle health sensors and initial concepts of data processing approaches. This allowed an initial estimate of VHM data transmission requirements for the airport surface. More recently, vehicle-level systems designed to process and analyze VHM data and draw conclusions on the current state of vehicle health have been undergoing testing and evaluation. These systems make use of vehicle system data that is mostly different from VHM data considered previously for airport surface transmission, and produce processed system outputs that will be also need to be archived, thus generating additional data load for AeroMACS. This paper provides an analysis of airport surface data transmission requirements resulting from the vehicle level reasoning systems, within the context of overall VHM data requirements.

  2. Link-layer jamming attacks on S-MAC

    OpenAIRE

    Law, Yee Wei; Hartel, Pieter; Hartog, den, D.N.; Havinga, Paul

    2005-01-01

    We argue that among denial-of-service (DoS) attacks, link-layer jamming is a more attractive option to attackers than radio jamming is. By exploiting the semantics of the link-layer protocol (aka MAC protocol), an attacker can achieve better efficiency than blindly jamming the radio signals alone. In this paper, we investigate some jamming attacks on S-MAC, the level of effectiveness and efficiency the attacks can potentially achieve, and a countermeasure that can be implemented against one o...

  3. Rand and MacIntyre on moral agency

    OpenAIRE

    Beadle, Ron

    2008-01-01

    This paper contrasts the work of Ayn Rand and Alasdair MacIntyre on moral agency. Both argue that moral agency requires the application of a consistent moral code across relationships with others and that such consistency is rarely evident in the modern social order. However, while MacIntyre holds this failure to be a defining feature of the modern social order, Rand holds this to be a failure of individuals and a marker of a wider cultural confusion. While Rand sees selfishness and capitalis...

  4. Alasdair MacIntyre: relatividad conceptual, tomismo y liberalismo

    Directory of Open Access Journals (Sweden)

    Carlos Isler S.

    2011-01-01

    Full Text Available Influenciado por Thomas Kuhn, Alasdair MacIntyre presenta una teoría conceptualmente relativista sobre las tradiciones de investigación, la cual pretende no sólo describir la estructura de las distintas tradiciones, sino también encontrar un principioque permita resolver las disputas entre ellas. Se expone esta teoría y se analiza su compatibilidad con el tomismo, tradición a la que MacIntyre dice pertenecer, y con el liberalismo, tradición a la que critica con vigor.

  5. Mac Lane method in the investigation of magnetic translation groups

    OpenAIRE

    Florek, Wojciech

    1998-01-01

    Central extensions of the three-dimensional translation group T=Z^3 by the unitary group U(1) (a group of factors) are considered within the frame of the Mac~Lane method. All nonzero vectors t in T are considered to be generators of T. This choice leads to very illustrative relations between the Mac~Lane method and Zak's approach to magnetic translation groups. It is shown that factor systems introduced by Zak and Brown can be realized only for the unitary group U(1) and for some of its finit...

  6. Generalised Filtering

    Directory of Open Access Journals (Sweden)

    Karl Friston

    2010-01-01

    Full Text Available We describe a Bayesian filtering scheme for nonlinear state-space models in continuous time. This scheme is called Generalised Filtering and furnishes posterior (conditional densities on hidden states and unknown parameters generating observed data. Crucially, the scheme operates online, assimilating data to optimize the conditional density on time-varying states and time-invariant parameters. In contrast to Kalman and Particle smoothing, Generalised Filtering does not require a backwards pass. In contrast to variational schemes, it does not assume conditional independence between the states and parameters. Generalised Filtering optimises the conditional density with respect to a free-energy bound on the model's log-evidence. This optimisation uses the generalised motion of hidden states and parameters, under the prior assumption that the motion of the parameters is small. We describe the scheme, present comparative evaluations with a fixed-form variational version, and conclude with an illustrative application to a nonlinear state-space model of brain imaging time-series.

  7. Notch filter

    Science.gov (United States)

    Shelton, G. B. (Inventor)

    1977-01-01

    A notch filter for the selective attenuation of a narrow band of frequencies out of a larger band was developed. A helical resonator is connected to an input circuit and an output circuit through discrete and equal capacitors, and a resistor is connected between the input and the output circuits.

  8. Link-layer jamming attacks on S-MAC

    NARCIS (Netherlands)

    Law, Yee Wei; Hartel, Pieter; Hartog, den Jerry; Havinga, Paul

    2005-01-01

    We argue that among denial-of-service (DoS) attacks, link-layer jamming is a more attractive option to attackers than radio jamming is. By exploiting the semantics of the link-layer protocol (aka MAC protocol), an attacker can achieve better efficiency than blindly jamming the radio signals alone. W

  9. Listening, Looking, and Learning with MacLang.

    Science.gov (United States)

    Frommer, Judith

    1989-01-01

    Describes how the capabilities of the MacLang authoring system allow foreign language teachers to develop computer-assisted instruction that meets the listening skill objectives of foreign language courses. Examples are given of the use of audio and video interfaces that facilitate listening comprehension. (Author/CB)

  10. Beamforming in Ad Hoc Networks: MAC Design and Performance Modeling

    Directory of Open Access Journals (Sweden)

    Khalil Fakih

    2009-01-01

    Full Text Available We examine in this paper the benefits of beamforming techniques in ad hoc networks. We first devise a novel MAC paradigm for ad hoc networks when using these techniques in multipath fading environment. In such networks, the use of conventional directional antennas does not necessarily improve the system performance. On the other hand, the exploitation of the potential benefits of smart antenna systems and especially beamforming techniques needs a prior knowledge of the physical channel. Our proposition performs jointly channel estimation and radio resource sharing. We validate the fruitfulness of the proposed MAC and we evaluate the effects of the channel estimation on the network performance. We then present an accurate analytical model for the performance of IEEE 802.11 MAC protocol. We extend the latter model, by introducing the fading probability, to derive the saturation throughput for our proposed MAC when the simplest beamforming strategy is used in real multipath fading ad hoc networks. Finally, numerical results validate our proposition.

  11. God, Sport Philosophy, Kinesiology: A MacIntyrean Examination

    Science.gov (United States)

    Twietmeyer, Gregg

    2015-01-01

    Sport philosophy is in crisis. This subdiscipline of kinesiology garners little to no respect and few tenure track lines in kinesiology departments. Why is this the case? Why isn't philosophy held in greater esteem? Is it possible that philosopher Alasdair MacIntyre's (2009) diagnosis found in "God, Philosophy, Universities" could…

  12. God, Sport Philosophy, Kinesiology: A MacIntyrean Examination

    Science.gov (United States)

    Twietmeyer, Gregg

    2015-01-01

    Sport philosophy is in crisis. This subdiscipline of kinesiology garners little to no respect and few tenure track lines in kinesiology departments. Why is this the case? Why isn't philosophy held in greater esteem? Is it possible that philosopher Alasdair MacIntyre's (2009) diagnosis found in "God, Philosophy, Universities" could…

  13. Roles of Mac-1 and glycoprotein IIb/IIIa integrins in leukocyte-platelet aggregate formation: stabilization by Mac-1 and inhibition by GpIIb/IIIa blockers.

    Science.gov (United States)

    Patko, Zsofia; Csaszar, Albert; Acsady, Gyorgy; Peter, Karlheinz; Schwarz, Meike

    2012-01-01

    Circulating platelet-leukocyte hetero-aggregates play an important role in acute cardiovascular events and hypersensitivity reactions. The association involves the receptor families of selectins and integrin. The objective of this study was to investigate the role of CD11b/CD18 integrin (Mac-1) in hetero-aggregate formation and search for a counter-receptor on platelets ready to interact with Mac-1. As a model of leukocytes, Mac-1 presenting Chinese hamster ovary (CHO) cells were used to evaluate the role of Mac-1 in hetero-aggregate formation. The amount of CHO cell-bound active and inactive platelets was measured by flow cytometry, while the counter-receptors on platelets were identified via using blocking antibodies. We observed significant platelet adhesion on Mac-1-bearing cells when platelet-rich plasma or activated platelets were present. Inactive platelets did not adhere to Mac-1-bearing cells. Addition of fibrinogen, a ligand of Mac-1 significantly increased platelet binding. CD40L was demonstrated to act similarly on Mac-1. Inhibition of platelet GpIIb/IIIa completely abolished CHO cell-platelet aggregation. In our study, we have shown for the first time that Mac-1 mediates the formation of hetero-aggregates without selectin tethering when Mac-1 ligands such as fibrinogen or CD40L are present and blockers of platelet GpIIb/IIIa are able to diminish this interaction.

  14. Band pass filters. Citations from the NTIS data base

    Science.gov (United States)

    Reed, W. E.

    1980-04-01

    A bibliography containing 242 abstracts addressing the design, fabrication, characterization, and application of band pass filters is presented. Radiofrequency, digital, acoustic surface wave, and X-ray filters are included.

  15. Pyrogen testing of lipid-based TPN using Mono Mac 6 monocyte cell line and DELFIA

    DEFF Research Database (Denmark)

    Moesby, Lise; Hansen, E W; Christensen, J D

    1997-01-01

    Measurement of lipopolysaccharide (LPS) induced interleukin-6 (IL-6) secretion in Mono Mac 6 cells.......Measurement of lipopolysaccharide (LPS) induced interleukin-6 (IL-6) secretion in Mono Mac 6 cells....

  16. MAC: identifying and correcting annotation for multi-nucleotide variations.

    Science.gov (United States)

    Wei, Lei; Liu, Lu T; Conroy, Jacob R; Hu, Qiang; Conroy, Jeffrey M; Morrison, Carl D; Johnson, Candace S; Wang, Jianmin; Liu, Song

    2015-08-01

    Next-Generation Sequencing (NGS) technologies have rapidly advanced our understanding of human variation in cancer. To accurately translate the raw sequencing data into practical knowledge, annotation tools, algorithms and pipelines must be developed that keep pace with the rapidly evolving technology. Currently, a challenge exists in accurately annotating multi-nucleotide variants (MNVs). These tandem substitutions, when affecting multiple nucleotides within a single protein codon of a gene, result in a translated amino acid involving all nucleotides in that codon. Most existing variant callers report a MNV as individual single-nucleotide variants (SNVs), often resulting in multiple triplet codon sequences and incorrect amino acid predictions. To correct potentially misannotated MNVs among reported SNVs, a primary challenge resides in haplotype phasing which is to determine whether the neighboring SNVs are co-located on the same chromosome. Here we describe MAC (Multi-Nucleotide Variant Annotation Corrector), an integrative pipeline developed to correct potentially mis-annotated MNVs. MAC was designed as an application that only requires a SNV file and the matching BAM file as data inputs. Using an example data set containing 3024 SNVs and the corresponding whole-genome sequencing BAM files, we show that MAC identified eight potentially mis-annotated SNVs, and accurately updated the amino acid predictions for seven of the variant calls. MAC can identify and correct amino acid predictions that result from MNVs affecting multiple nucleotides within a single protein codon, which cannot be handled by most existing SNV-based variant pipelines. The MAC software is freely available and represents a useful tool for the accurate translation of genomic sequence to protein function.

  17. Generation of MAC waves by convection in Earth's core

    Science.gov (United States)

    Jaupart, Etienne; Buffett, Bruce

    2017-05-01

    Convection in Earth's core is a viable mechanism for generating MAC waves when the top of the core is stably stratified. We quantify the generation mechanism by extending the physical description of MAC waves to include a source term due to buoyancy forces in the convecting part of the core. Solutions for the forced motion are obtained using a Green's function, which is constructed from the eigenfunctions for the unforced motion. When the source term is evaluated using the output of a numerical geodynamo model, the largest excitation occurs at even spherical harmonic degrees, corresponding to waves with symmetric azimuthal flow about the equator. We also find that the magnitude of the source term decreases at periods shorter than about 60 yr. As a result most of the wave generation is confined to waves with periods of 60 yr or longer. Quantitative predictions for the wave amplitudes depend on the projection of the source term into the eigenfunction of the waves. Strong stratification limits the penetration of density anomalies into the stratified layer, which means that the source term is confined to the lowermost part of the layer. Overtones of MAC waves with large amplitudes in the lower part of the stratified layer are more effectively generated by convection, even though these waves are heavily damped by magnetic diffusion. Generation of MAC waves by convection establishes a physical link between observable wave motion and deeper convective processes. Detection of changes in the amplitude and phase of MAC waves would constrain the generation processes and offer insights into the nature of the convection.

  18. 42 CFR 405.1110 - MAC reviews on its own motion.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 2 2010-10-01 2010-10-01 false MAC reviews on its own motion. 405.1110 Section 405....1110 MAC reviews on its own motion. (a) General rule. The MAC may decide on its own motion to review a decision or dismissal issued by an ALJ. CMS or any of its contractors may refer a case to the MAC for it to...

  19. Minimum Alveolar Concentration for Blunting Adrenergic Responses (MAC-BAR) of Sevoflurane in Dogs

    OpenAIRE

    YAMASHITA, Kazuto; FURUKAWA, Erika; ITAMI, Takaharu; ISHIZUKA, Tomohito; TAMURA, Jun; MIYOSHI, Kenjirou

    2012-01-01

    It is well known that heart rate or arterial blood pressure may increase in response to surgical stimulation despite the absence of a purposeful movement. However, there is limited information regarding anesthetic requirement for blunting adrenergic response in dogs. This study was designed to compare the minimum alveolar concentrations of sevoflurane required to prevent autonomic response (MAC-BAR) and purposeful movement (MAC) in dogs. Sevoflurane MAC-BAR and MAC were determined in 5 beagle...

  20. MDS-Mac: a scheduled MAC for localization, time-synchronisation and communication in underwater acoustic networks

    NARCIS (Netherlands)

    Kleunen, van Wouter; Meratnia, Nirvana; Havinga, Paul J.M.

    2012-01-01

    In this paper we describe a design for an underwater MAC protocol which combines localization, time-synchronisation and communication. This protocol is designed for small-scale clustered networks in which all nodes are able to ommunicate with each other. We consider an integrated design of localizat

  1. TR-MAC: an energy-efficient MAC protocol for wireless sensor networks exploiting noise-based transmitted reference modulation

    NARCIS (Netherlands)

    Morshed, S.; Dimitrova, D.C.; Brogle, M.; Braun, T.; Heijenk, Gerhard J.

    Energy-constrained behavior of sensor nodes is one of the most important criteria for successful deployment of wireless sensor net- works. The medium access control (MAC) protocol determines the time a sensor node transceiver spends listening or transmitting, and hence the energy consumption of the

  2. CoR-MAC: Contention over Reservation MAC Protocol for Time-Critical Services in Wireless Body Area Sensor Networks.

    Science.gov (United States)

    Yu, Jeongseok; Park, Laihyuk; Park, Junho; Cho, Sungrae; Keum, Changsup

    2016-05-09

    Reserving time slots for urgent data, such as life-critical information, seems to be very attractive to guarantee their deadline requirements in wireless body area sensor networks (WBASNs). On the other hand, this reservation imposes a negative impact on performance for the utilization of a channel. This paper proposes a new channel access scheme referred to as the contention over reservation MAC (CoR-MAC) protocol for time-critical services in wireless body area sensor networks. CoR-MAC uses the dual reservation; if the reserved time slots are known to be vacant, other nodes can access the time slots by contention-based reservation to maximize the utilization of a channel and decrease the delay of the data. To measure the effectiveness of the proposed scheme against IEEE 802.15.4 and IEEE 802.15.6, we evaluated their performances with various performance indexes. The CoR-MAC showed 50% to 850% performance improvement in terms of the delay of urgent and time-critical data according to the number of nodes.

  3. Library Signage: Applications for the Apple Macintosh and MacPaint.

    Science.gov (United States)

    Diskin, Jill A.; FitzGerald, Patricia

    1984-01-01

    Describes specific applications of the Macintosh computer at Carnegie-Mellon University Libraries, where MacPaint was used as a flexible, easy to use, and powerful tool to produce informational, instructional, and promotional signage. Profiles of system hardware and software, an evaluation of the computer program MacPaint, and MacPaint signage…

  4. 42 CFR 405.1050 - Removal of a hearing request from an ALJ to the MAC.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 2 2010-10-01 2010-10-01 false Removal of a hearing request from an ALJ to the MAC... Removal of a hearing request from an ALJ to the MAC. If a request for hearing is pending before an ALJ, the MAC may assume responsibility for holding a hearing by requesting that the ALJ send the hearing...

  5. 42 CFR 405.1108 - MAC actions when request for review or escalation is filed.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 2 2010-10-01 2010-10-01 false MAC actions when request for review or escalation...) Medicare Appeals Council Review § 405.1108 MAC actions when request for review or escalation is filed. (a) Except as specified in paragraphs (c) and (d) of this section, when a party requests that the MAC review...

  6. Traffic-adaptive duty cycle adaptation in TR-MAC protocol for wireless sensor networks

    NARCIS (Netherlands)

    Morshed, Sarwar; Baratchi, Mitra; Heijenk, Geert

    2016-01-01

    The Medium Access Control (MAC) layer can influence the energy consumption of a wireless sensor network (WSN) to a significant level. TR-MAC is an energy-efficient preamble sampling based MAC protocol for low power WSNs suitable for low data rate and low duty cycle scenario. However, low data rate i

  7. 42 CFR 405.1102 - Request for MAC review when ALJ issues decision or dismissal.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 2 2010-10-01 2010-10-01 false Request for MAC review when ALJ issues decision or...) Medicare Appeals Council Review § 405.1102 Request for MAC review when ALJ issues decision or dismissal. (a)(1) A party to the ALJ hearing may request a MAC review if the party files a written request for...

  8. Filtering and control of wireless networked systems

    CERN Document Server

    Zhang, Dan; Yu, Li

    2017-01-01

    This self-contained book, written by leading experts, offers a cutting-edge, in-depth overview of the filtering and control of wireless networked systems. It addresses the energy constraint and filter/controller gain variation problems, and presents both the centralized and the distributed solutions. The first two chapters provide an introduction to networked control systems and basic information on system analysis. Chapters (3–6) then discuss the centralized filtering of wireless networked systems, presenting different approaches to deal with energy efficiency and filter/controller gain variation problems. The next part (chapters 7–10) explores the distributed filtering of wireless networked systems, addressing the main problems of energy constraint and filter gain variation. The final part (chapters 11–14) focuses on the distributed control of wireless networked systems.

  9. Reach Address Database (RAD)

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Reach Address Database (RAD) stores the reach address of each Water Program feature that has been linked to the underlying surface water features (streams,...

  10. License Address List

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Address list generated from National Saltwater Angler Registry. Used in conjunction with an address-based sample as per survey design.

  11. CRYSTAL FILTER TEST SET

    Science.gov (United States)

    CRYSTAL FILTERS, *HIGH FREQUENCY, *RADIOFREQUENCY FILTERS, AMPLIFIERS, ELECTRIC POTENTIAL, FREQUENCY, IMPEDANCE MATCHING , INSTRUMENTATION, RADIOFREQUENCY, RADIOFREQUENCY AMPLIFIERS, TEST EQUIPMENT, TEST METHODS

  12. The minimum alveolar concentration (MAC) and hemodynamic effects of halothane, isoflurane, and sevoflurane in newborn swine.

    Science.gov (United States)

    Lerman, J; Oyston, J P; Gallagher, T M; Miyasaka, K; Volgyesi, G A; Burrows, F A

    1990-10-01

    To determine the minimum alveolar concentration (MAC) and hemodynamic responses to halothane, isoflurane, and sevoflurane in newborn swine, 36 fasting swine 4-10 days of age were anesthetized with one of the three volatile anesthetics in 100% oxygen. MAC was determined for each swine. Carotid artery and internal jugular catheters were inserted and each swine was allowed to recover for 48 h. After recovery, heart rate (HR), systemic systolic arterial pressure (SAP), and cardiac index (CI) were measured awake and then at 0.5, 1.0, and 1.5 MAC of the designated anesthetic in random sequence. The (mean +/- SD) MAC for halothane was 0.90 +/- 0.12%; the MAC for isoflurane was 1.48 +/- 0.21%; and the MAC for sevoflurane was 2.12 +/- 0.39%. Awake (mean +/- SD) measurements of HR, SAP, and CI did not differ significantly among the three groups. Compared to the awake HR, the mean HR decreased 35% at 1.5 MAC halothane (P less than 0.001), 19% at 1.5 MAC isoflurane (P less than 0.005), and 31% at 1.5 MAC sevoflurane (P less than 0.005). Compared to awake SAP, mean SAP measurements decreased 46% at 1.5 MAC halothane (P less than 0.001), 43% at 1.5 MAC isoflurane (P less than 0.001), and 36% at 1.5 MAC sevoflurane (P less than 0.005). Mean SAP at 1.0 and 1.5 MAC halothane and isoflurane were significantly less than those measured at equipotent concentrations of sevoflurane (P less than 0.005). Compared to awake CI, mean CI measurements decreased 53% at 1.5 MAC halothane (P less than 0.001) and 43% at 1.5 MAC isoflurane (P less than 0.005).(ABSTRACT TRUNCATED AT 250 WORDS)

  13. MAC-awake of isoflurane, enflurane and halothane evaluated by slow and fast alveolar washout.

    Science.gov (United States)

    Gaumann, D M; Mustaki, J P; Tassonyi, E

    1992-01-01

    End-tidal anaesthetic concentrations at first eye opening in response to a verbal command during recovery from anaesthesia (MAC-awake), were measured for isoflurane (n = 16), enflurane (n = 16) and halothane (n = 14). MAC-awake was measured during either slow or fast alveolar washout. Slow washout was obtained by decreasing anaesthetic concentrations in predetermined steps of 15 min, assuming equilibration between brain and alveolar partial pressures. Fast alveolar washout was obtained by discontinuation of the inhalation anaesthetic, which had been maintained at 1 MAC for at least 15 min. Mean MAC-awake obtained with slow alveolar washout was similar for isoflurane (0.25 (SD 0.03) MAC), and enflurane (0.27 (0.04) MAC) and significantly greater than values obtained by fast alveolar washout (isoflurane: 0.19 (0.03) MAC; enflurane: 0.20 (0.03) MAC). The MAC-awake of isoflurane and enflurane was significantly less than that of halothane, which was 0.59 (0.10) MAC as evaluated by the slow and 0.50 (0.05) MAC as evaluated by the fast alveolar washout method. Recovery time from anaesthesia with fast alveolar washout was 8.8 (4.0) min for halothane, which was not different from isoflurane (15 (2.5) min), but significantly shorter than for enflurane (22 (10) min), reflecting differences in the anaesthetic concentration gradient between MAC and MAC-awake values. These data do not support the hypothesis of a uniform ratio between MAC and MAC-awake values.

  14. Beams Propagation Modelled by Bi-filters

    OpenAIRE

    Lacaze, Bernard

    2010-01-01

    In acoustic, ultrasonic or electromagnetic propagation, crossed media are often modelled by linear filters with complex gains in accordance with the Beer-Lambert law. This paper addresses the problem of propagation in media where polarization has to be taken into account. Because waves are now bi-dimensional, an unique filter is not sufficient to represent the effects of the medium. We propose a model which uses four linear invariant filters, which allows to take into account exchanges betwee...

  15. Tool for Generation of MAC/GMC Representative Unit Cell for CMC/PMC Analysis

    Science.gov (United States)

    Murthy, Pappu L. N.; Pineda, Evan J.

    2016-01-01

    This document describes a recently developed analysis tool that enhances the resident capabilities of the Micromechanics Analysis Code with the Generalized Method of Cells (MAC/GMC) 4.0. This tool is especially useful in analyzing ceramic matrix composites (CMCs), where higher fidelity with improved accuracy of local response is needed. The tool, however, can be used for analyzing polymer matrix composites (PMCs) as well. MAC/GMC 4.0 is a composite material and laminate analysis software developed at NASA Glenn Research Center. The software package has been built around the concept of the generalized method of cells (GMC). The computer code is developed with a user friendly framework, along with a library of local inelastic, damage, and failure models. Further, application of simulated thermomechanical loading, generation of output results, and selection of architectures to represent the composite material have been automated to increase the user friendliness, as well as to make it more robust in terms of input preparation and code execution. Finally, classical lamination theory has been implemented within the software, wherein GMC is used to model the composite material response of each ply. Thus, the full range of GMC composite material capabilities is available for analysis of arbitrary laminate configurations as well. The primary focus of the current effort is to provide a graphical user interface (GUI) capability that generates a number of different user-defined repeating unit cells (RUCs). In addition, the code has provisions for generation of a MAC/GMC-compatible input text file that can be merged with any MAC/GMC input file tailored to analyze composite materials. Although the primary intention was to address the three different constituents and phases that are usually present in CMCs-namely, fibers, matrix, and interphase-it can be easily modified to address two-phase polymer matrix composite (PMC) materials where an interphase is absent. Currently, the

  16. Una lectura interpretativa de Tras la virtud, de Alasdair MacIntyre - An Interpretive Reading of After Virtue, by Alasdair MacIntyre

    Directory of Open Access Journals (Sweden)

    Fernando Fernández-Llebrez

    2010-12-01

    Full Text Available This article centers on the thought of Alasdair MacIntyre, whose most prominente work, After Virtue, is considered a classic of political science. In contrast with other reviews, this article will examine After Virtue within the broader context of MacIntyre’s thinking and publications. An overview of MacIntyre’s literary corpus and the evolution of his thinking will shed light on the volume examined and trace certain ideas that are characteristic of this Scottish political philosopher. Matters that remained unsettled in After Virtue have become over time more defined in MacIntyre’s thinking, such as the influence exerted upon him by Thomas Aquinas.

  17. Nanophotonic filters for digital imaging

    Science.gov (United States)

    Walls, Kirsty

    There has been an increasing demand for low cost, portable CMOS image sensors because of increased integration, and new applications in the automotive, mobile communication and medical industries, amongst others. Colour reproduction remains imperfect in conventional digital image sensors, due to the limitations of the dye-based filters. Further improvement is required if the full potential of digital imaging is to be realised. In alternative systems, where accurate colour reproduction is a priority, existing equipment is too bulky for anything but specialist use. In this work both these issues are addressed by exploiting nanophotonic techniques to create enhanced trichromatic filters, and multispectral filters, all of which can be fabricated on-chip, i.e. integrated into a conventional digital image sensor, to create compact, low cost, mass produceable imaging systems with accurate colour reproduction. The trichromatic filters are based on plasmonic structures. They exploit the excitation of surface plasmon resonances in arrays of subwavelength holes in metal films to filter light. The currently-known analytical expressions are inadequate for optimising all relevant parameters of a plasmonic structure. In order to obtain arbitrary filter characteristics, an automated design procedure was developed that integrated a genetic algorithm and 3D finite-difference time-domain tool. The optimisation procedure's efficacy is demonstrated by designing a set of plasmonic filters that replicate the CIE (1931) colour matching functions, which themselves mimic the human eye's daytime colour response.

  18. Distinguishing and Second-Preimage Attacks on CBC-Like MACs

    Science.gov (United States)

    Jia, Keting; Wang, Xiaoyun; Yuan, Zheng; Xu, Guangwu

    This paper first presents a new distinguishing attack on the CBC-MAC structure based on block ciphers in cipher block chaining (CBC) mode. This attack detects a CBC-like MAC from random functions. The second result of this paper is a second-preimage attack on the CBC-MAC, which is an extension of the attack of Brincat and Mitchell. The attack also covers MT-MAC, PMAC and MACs with three-key enciphered CBC mode. Instead of exhaustive search, both types of attacks are of birthday attack complexity.

  19. Digital filters

    CERN Document Server

    Hamming, Richard W

    1997-01-01

    Digital signals occur in an increasing number of applications: in telephone communications; in radio, television, and stereo sound systems; and in spacecraft transmissions, to name just a few. This introductory text examines digital filtering, the processes of smoothing, predicting, differentiating, integrating, and separating signals, as well as the removal of noise from a signal. The processes bear particular relevance to computer applications, one of the focuses of this book.Readers will find Hamming's analysis accessible and engaging, in recognition of the fact that many people with the s

  20. Robust filtering for uncertain systems a parameter-dependent approach

    CERN Document Server

    Gao, Huijun

    2014-01-01

    This monograph provides the reader with a systematic treatment of robust filter design, a key issue in systems, control and signal processing, because of the fact that the inevitable presence of uncertainty in system and signal models often degrades the filtering performance and may even cause instability. The methods described are therefore not subject to the rigorous assumptions of traditional Kalman filtering. The monograph is concerned with robust filtering for various dynamical systems with parametric uncertainties, and focuses on parameter-dependent approaches to filter design. Classical filtering schemes, like H2 filtering and H¥ filtering, are addressed, and emerging issues such as robust filtering with constraints on communication channels and signal frequency characteristics are discussed. The text features: ·        design approaches to robust filters arranged according to varying complexity level, and emphasizing robust filtering in the parameter-dependent framework for the first time; ·...

  1. MAC Protocol for Data Gathering in Wireless Sensor Networks with the Aid of Unmanned Aerial Vehicles

    Directory of Open Access Journals (Sweden)

    VLADUTA, A.-V.

    2016-05-01

    Full Text Available Data gathering in wireless sensor networks by employing unmanned aerial vehicles has been a subject of real interest in the recent years. While drones are seen as an efficient method of data gathering in almost any environment, wireless sensor networks are the key elements for generating data because they have low dimensions, improved flexibility, decreased power consumption and costs. This paper addresses the communication at the Medium Access Control (MAC layer between static deployed sensors and a moving drone whose unique role is to collect data from all sensors on its path. The most important part of the proposed protocol consists of prioritizing the sensors in such a manner that each of them has a fair chance to communicate with the drone. Simulations are performed in NS-2 and results demonstrate the capabilities of the proposed protocol.

  2. Magnetic activated cell sorting (MACS): utility in assisted reproduction.

    Science.gov (United States)

    Makker, Kartikeya; Agarwal, Ashok; Sharma, Rakesh K

    2008-07-01

    Assisted reproductive techniques (ART) have now been extensively incorporated in the management of infertile couples. But even after rapid methodological and technological advances the success rates of these procedures have been below expectations. This has led to development of many sperm preparation protocols to obtain an ideal semen sample for artificial reproduction. Sperm apoptosis has been heavily linked to failures in reproductive techniques. One of the earliest changes shown by apoptotic spermatozoa is externalization of phosphatidyl serine. Magnetic activated cell sorting (MACS) is a novel sperm preparation technique that separates apoptotic and non-apoptotic spermatozoa based on the expression of phosphatidylserine. This has led to the incorporation of MACS as a sperm preparation technique. The review highlights the principle and mechanism of this novel technique and enumerates its advantages as a sperm preparation technique. Its utility in ART as an efficient tool for sperm recovery and its application in cryopreservation of semen samples is also explained.

  3. Secure MAC for Wireless Sensor Networks through RBFNN

    Directory of Open Access Journals (Sweden)

    P.Sankara Rao

    2010-08-01

    Full Text Available This paper discusses an application of a neural network in wireless sensor network security. It presents a Radial Basic Function Neural Network based media access control protocol (MAC to secure a CSMA-based wireless sensor network against the denial-of-service attacks launched by adversaries. The Radial Basic Function Neural Network enhances the security of a WSN by constantly monitoring the parameters that exhibit unusual variations in case of an attack. The RBFN shuts down the MAC layer and the physical layer of the sensor node when the suspicion factor, the output of the MLP, exceeds a preset threshold level. The MLP-guarded secure WSN is implemented using the Prowler simulator. Simulation results show that the MLP helps in extending the lifetime of the WSN.

  4. On the Development of Low Power MAC Protocol for WBANs

    CERN Document Server

    Ullah, Sana; Kwak, Kyung Sup

    2009-01-01

    Current advances in wireless communication, microelectronics, semiconductor technologies, and intelligent sensors have contributed to the development of unobtrusive WBANs. These networks provide long term health monitoring of patients without any constraint in their normal activities. Traditional MAC protocols do not accommodate the assorted WBAN traffic requirements in a power efficient manner. In this paper, we present a brief discussion on the development process of a low power MAC protocol for WBANs. We observe the behavior of a beacon-enabled IEEE 802.15.4 for on-body sensor networks. We further propose a low power technique called traffic based wakeup mechanism for a WBAN that exploits the traffic patterns of the BAN Nodes to ensure power efficient and reliable communication.

  5. Activity Modelling and Comparative Evaluation of WSN MAC Security Attacks

    DEFF Research Database (Denmark)

    Pawar, Pranav M.; Nielsen, Rasmus Hjorth; Prasad, Neeli R.

    2012-01-01

    and initiate security attacks that disturb the normal functioning of the network in a severe manner. Such attacks affect the performance of the network by increasing the energy consumption, by reducing throughput and by inducing long delays. Of all existing WSN attacks, MAC layer attacks are considered....... The second aim of the paper is to simulate these attacks on hybrid MAC mechanisms, which shows the performance degradation of aWSN under the considered attacks. The modelling and implementation of the security attacks give an actual view of the network which can be useful in further investigating secure......Applications of wireless sensor networks (WSNs) are growing tremendously in the domains of habitat, tele-health, industry monitoring, vehicular networks, home automation and agriculture. This trend is a strong motivation for malicious users to increase their focus on WSNs and to develop...

  6. Gravitational Duality in MacDowell-Mansouri Gauge Theory

    CERN Document Server

    García-Compéan, H; Ramírez, C

    1998-01-01

    Strong-weak duality invariance can only be defined for particular sectors of supersymmetric Yang-Mills theories. Nevertheless, for full non-Abelian non-supersymmetric theories, dual theories with inverted couplings, have been found. We show that an analogous procedure allows to find the dual action to the gauge theory of gravity constructed by the MacDowell-Mansouri model plus the superposition of a $\\Theta$ term.

  7. Mac OS X Server Snow Leopard 雪豹

    Institute of Scientific and Technical Information of China (English)

    王炳晨

    2010-01-01

    日前,苹果公司宣布推出Mac OSX Server Snow Leopard服务器系统。这是一个真正意义的全64位操作系统,为充分发挥多核心处理器和内存的性能而设计,且完全兼容32位应用程序。

  8. LHC@home online tutorial for Mac users - recording

    CERN Document Server

    CERN. Geneva

    2016-01-01

    A step-by-step online tutorial about LHC@home for Mac users by Alexandre Racine. It contains detailed instructions on how-to-join this volunteer computing project.  There are 3 screen capture videos with the real installation process accelerated attached to the event page. This 5' video is linked from http://lhcathome.web.cern.ch/join-us Also from the CDS e-learning category.

  9. Archimedes Mass Filter Vaporizer

    Science.gov (United States)

    Putvinski, S.; Agnew, A. F.; Cluggish, B. P.; Ohkawa, T.; Sevier, L.; Umstadter, K. R.; Dresvin, S. V.; Kuteev, B. V.; Feygenson, O. N.; Ivanov, D. V.; Zverev, S. G.; Miroshnikov, I. V.; Egorov, S. M.; Kiesewetter, D. V.; Maliugin, V. I.

    2001-10-01

    Archimedes Technology Group, Inc., is developing a plasma mass separator called the Archimedes Filter that separates waste oxide mixtures ion by ion into two mass groups: light and heavy. Since high-level waste at Hanford has 99.9its radioactivity associated with heavy elements, the Archimedes Filter can effectively decontaminate over three-quarters of that waste. The Filter process involves some preprocessing followed by volatilization and separation by the magnetic and electric fields of the main plasma. This presentation describes the approach to volatilization of the waste oxy-hydroxide mixture by means of a very high heat flux (q > 10 MW/m2). Such a high heat flux is required to ensure congruent evaporation of the complex oxy-hydroxide mixture and is achieved by injection of small droplets of molten waste into an inductively coupled plasma (ICP) torch. This presentation further addresses different issues related to evaporation of the waste including modeling of droplet evaporation, estimates of parameters of plasma torch, and 2D modeling of the plasma. The experimental test bed for oxide vaporization and results of the initial experiments on oxide evaporation in 60 kW ICP torch will also be described.

  10. On the Selection of MAC Optimised Routing Protocol for VANET

    Directory of Open Access Journals (Sweden)

    Kanu Priya

    2017-02-01

    Full Text Available In today‘s era of modernization, the concept of smart vehicles, smart cities and automated vehicles is trending day by day. VANET (Vehicular Adhoc Network has also been emerging as a potential applicant to enable these smart applications. Though VANET is very much similar to MANET (Mobile Adhoc Network but VANET has more severe challenges as compared to MANET due to hostile channel conditions and high degree of mobility. So lot of work related to MAC and Network Layer need attention from the network designers. In this paper MAC Layer has been optimised in terms of Queue Size by using QoS Parameters namely Packet Collision Rate, Packet Drop Rate, Throughput Rate and Broadcast Rate. In doing so, simulative investigations have been done to find out optimum queue size. For this purpose various routing protocols namely DSDV, AODV, ADV and GOD have been considered and optimum queue length for each of these have been obtained. Further the most efficient routing protocol has also been identified. Moreover this paper also compares the performance of most efficient Routing Protocols selected in terms of QoS parameters for different MAC Interfaces.

  11. An Evaluation of Mass Absorption Cross-Section for Optical Carbon Analysis on Teflon Filter Media.

    Science.gov (United States)

    Presler-Jur, Paige; Doraiswamy, Prakash; Hammond, Oki; Rice, Joann

    2017-04-05

    Black carbon (BC) or elemental carbon (EC) is a by-product of incomplete fuel combustion, and contributes adversely to human health, visibility, and climate impacts. Previous studies have examined non-destructive techniques for particle light attenuation measurements on Teflon(®) filters to estimate BC. The incorporation of an inline Magee Scientific OT21 Transmissometer into the MTL AH-225 robotic weighing system provides the opportunity to perform optical transmission measurements on Teflon(®) filters at the same time as the gravimetric mass measurement. In this study, we characterize the performance of the inline OT21, and apply it to determine the mass absorption cross-section (MAC) of PM2.5 BC across the U.S. We analyzed 5393 archived Teflon(®) filters from the Chemical Speciation Network (CSN) collected during 2010-2011 and determined MAC by comparing light attenuation on Teflon(®) filters to corresponding thermal EC on quartz-fiber filters. Results demonstrated the importance of the initial transmission (I0) value used in light attenuation calculations. While light transmission varied greatly within filter lots, the average I0 of filter blanks during from the sampling period provided an estimate for archived filters. For newly collected samples, it is recommended that filter-specific I0 measurements be made (i.e., same filter before sample collection). The estimated MAC ranged from 6.9 to 9.4 m(2)/g that varied by region and season across the U.S., indicating that using a default value may lead to under- or over-estimated BC concentrations. An analysis of the chemical composition of these samples indicated good correlation with EC for samples with higher EC content as a fraction of total PM2.5 mass, while the presence of light scattering species such as crustal elements impacted the correlation affecting the MAC estimate. Overall, the method is demonstrated to be a quick, cost-effective approach to estimate BC from archived and newly sampled Teflon

  12. 42 CFR 423.2140 - MAC Review of ALJ decision in a case remanded by a Federal District Court.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 3 2010-10-01 2010-10-01 false MAC Review of ALJ decision in a case remanded by a... BENEFIT Reopening, ALJ Hearings, MAC review, and Judicial Review § 423.2140 MAC Review of ALJ decision in..., when a case is remanded by a Federal District Court for further consideration and the MAC remands the...

  13. Leukocyte integrin Mac-1 regulates thrombosis via interaction with platelet GPIbα.

    Science.gov (United States)

    Wang, Yunmei; Gao, Huiyun; Shi, Can; Erhardt, Paul W; Pavlovsky, Alexander; A Soloviev, Dmitry; Bledzka, Kamila; Ustinov, Valentin; Zhu, Liang; Qin, Jun; Munday, Adam D; Lopez, Jose; Plow, Edward; Simon, Daniel I

    2017-05-30

    Inflammation and thrombosis occur together in many diseases. The leukocyte integrin Mac-1 (also known as integrin αMβ2, or CD11b/CD18) is crucial for leukocyte recruitment to the endothelium, and Mac-1 engagement of platelet GPIbα is required for injury responses in diverse disease models. However, the role of Mac-1 in thrombosis is undefined. Here we report that mice with Mac-1 deficiency (Mac-1(-/-)) or mutation of the Mac-1-binding site for GPIbα have delayed thrombosis after carotid artery and cremaster microvascular injury without affecting parameters of haemostasis. Adoptive wild-type leukocyte transfer rescues the thrombosis defect in Mac-1(-/-) mice, and Mac-1-dependent regulation of the transcription factor Foxp1 contributes to thrombosis as evidenced by delayed thrombosis in mice with monocyte-/macrophage-specific overexpression of Foxp1. Antibody and small-molecule targeting of Mac-1:GPIbα inhibits thrombosis. Our data identify a new pathway of thrombosis involving leukocyte Mac-1 and platelet GPIbα, and suggest that targeting this interaction has anti-thrombotic therapeutic potential with reduced bleeding risk.

  14. Characteristics of Mycobacterium avium complex (MAC) pulmonary disease in previously treated lung cancer patients.

    Science.gov (United States)

    Meier, Erin; Pennington, Kelly; Gallo de Moraes, Alice; Escalante, Patricio

    2017-01-01

    Mycobacterium avium complex (MAC) is responsible for a large portion of non-tuberculous mycobacterial (NTM) infections worldwide. Host factors such as active malignancy, immunosuppression, chronic obstructive pulmonary disease (COPD) and bronchiectasis increase the risk of MAC infection. However, the relationship between previously treated lung cancer with subsequent development of MAC pulmonary disease and treatment outcomes have not been previously studied. We retrospectively identified all patients with lung cancer and MAC pulmonary disease documented in medical records at Mayo Clinic between January 2005 and October 2016. Patients who were diagnosed with MAC pulmonary disease before or at the time of lung cancer diagnosis were excluded. Patients meeting all inclusion criteria underwent chart review for prior oncologic treatments, clinical characteristics, and MAC treatment response. We identified 13 patients with MAC pulmonary disease and prior lung cancer, including 4 men and 9 women. Eight patients had structural lung disease that can predispose to MAC pulmonary disease, including bronchiectasis (23.0%) and COPD (46.2%). Four (30.8%) had no apparent immunosuppression or other risk factor(s) for MAC pulmonary disease. Primary pulmonary malignancies included pulmonary carcinoid, adenocarcinoma, and squamous cell carcinoma. Ten (76.9%) patients were started on antimicrobial treatment for MAC, and 8 (61.5%) patients completed MAC treatment with 6 (46.1%) patients achieving symptomatic improvement. MAC pulmonary disease in previously treated lung cancer can occur without apparent risk factors for this NTM infection. Symptomatic improvement with MAC antimicrobial therapy appears to be lower than expected but comorbidities might influence outcomes in this patient population.

  15. Optimal Filtering of Malicious IP Sources

    CERN Document Server

    Soldo, Fabio; Argyraki, Katerina

    2008-01-01

    How can we protect the network infrastructure from malicious traffic, such as scanning, malicious code propagation, and distributed denial-of-service (DDoS) attacks? One mechanism for blocking malicious traffic is filtering: access control lists (ACLs) can selectively block traffic based on fields of the IP header. Filters (ACLs) are already available in the routers today but are a scarce resource because they are stored in the expensive ternary content addressable memory (TCAM). In this paper, we develop, for the first time, a framework for studying filter selection as a resource allocation problem. Within this framework, we study five practical cases of source address/prefix filtering, which correspond to different attack scenarios and operator's policies. We show that filter selection optimization leads to novel variations of the multidimensional knapsack problem and we design optimal, yet computationally efficient, algorithms to solve them. We also evaluate our approach using data from Dshield.org and dem...

  16. ADVANCED HOT GAS FILTER DEVELOPMENT

    Energy Technology Data Exchange (ETDEWEB)

    E.S. Connolly; G.D. Forsythe

    2000-09-30

    DuPont Lanxide Composites, Inc. undertook a sixty-month program, under DOE Contract DEAC21-94MC31214, in order to develop hot gas candle filters from a patented material technology know as PRD-66. The goal of this program was to extend the development of this material as a filter element and fully assess the capability of this technology to meet the needs of Pressurized Fluidized Bed Combustion (PFBC) and Integrated Gasification Combined Cycle (IGCC) power generation systems at commercial scale. The principal objective of Task 3 was to build on the initial PRD-66 filter development, optimize its structure, and evaluate basic material properties relevant to the hot gas filter application. Initially, this consisted of an evaluation of an advanced filament-wound core structure that had been designed to produce an effective bulk filter underneath the barrier filter formed by the outer membrane. The basic material properties to be evaluated (as established by the DOE/METC materials working group) would include mechanical, thermal, and fracture toughness parameters for both new and used material, for the purpose of building a material database consistent with what is being done for the alternative candle filter systems. Task 3 was later expanded to include analysis of PRD-66 candle filters, which had been exposed to actual PFBC conditions, development of an improved membrane, and installation of equipment necessary for the processing of a modified composition. Task 4 would address essential technical issues involving the scale-up of PRD-66 candle filter manufacturing from prototype production to commercial scale manufacturing. The focus would be on capacity (as it affects the ability to deliver commercial order quantities), process specification (as it affects yields, quality, and costs), and manufacturing systems (e.g. QA/QC, materials handling, parts flow, and cost data acquisition). Any filters fabricated during this task would be used for product qualification tests

  17. Convergent Filter Bases

    OpenAIRE

    Coghetto Roland

    2015-01-01

    We are inspired by the work of Henri Cartan [16], Bourbaki [10] (TG. I Filtres) and Claude Wagschal [34]. We define the base of filter, image filter, convergent filter bases, limit filter and the filter base of tails (fr: filtre des sections).

  18. Convergent Filter Bases

    Directory of Open Access Journals (Sweden)

    Coghetto Roland

    2015-09-01

    Full Text Available We are inspired by the work of Henri Cartan [16], Bourbaki [10] (TG. I Filtres and Claude Wagschal [34]. We define the base of filter, image filter, convergent filter bases, limit filter and the filter base of tails (fr: filtre des sections.

  19. Inferior vena cava filters in cancer patients: to filter or not to filter

    Directory of Open Access Journals (Sweden)

    Hikmat Abdel-Razeq

    2011-03-01

    Full Text Available Hikmat Abdel-Razeq1, Asem Mansour2, Yousef Ismael1, Hazem Abdulelah11Department of Internal Medicine, 2Department of Radiology, King Hussein Cancer Center, Amman, JordanPurpose: Cancer and its treatment are recognized risk factors for venous thromboembolism (VTE; active cancer accounts for almost 20% of all newly diagnosed VTE. Inferior vena cava (IVC filters are utilized to provide mechanical thromboprophylaxis to prevent pulmonary embolism (PE or to avoid bleeding from systemic anticoagulation in high-risk situations. In this report, and utilizing a case study, we will address the appropriate utilization of such filters in cancer patients.Methods: The case of a 43-year-old female patient with rectal cancer, who developed deep vein thrombosis following a complicated medical course, will be presented. The patient was anticoagulated with a low molecular weight heparin, but a few months later and following an episode of bleeding, an IVC filter was planned. Using the PubMed database, articles published in English language addressing issues related to IVC filters in cancer patients were accessed and will be presented.Results: Many recent studies questioned the need to insert IVC filters in advanced-stage cancer patients, particularly those whose anticipated survival is short and prevention of PE may be of little clinical benefit and could be a poor utilization of resources.Conclusion: Systemic anticoagulation can be safely offered for the majority of cancer patients. When the risk of bleeding or pulmonary embolism is high, IVC filters can be utilized. However, placement of such filters should take into consideration the stage of disease and life expectancy of such patients.Keywords: anticoagulation, bleeding, chemotherapy

  20. The role of electron scattering from registration detector in the "Troitsk nu-mass" MAC-E type spectrometer

    Science.gov (United States)

    Grigorieva, P. V.; Nozik, A. A.; Pantuev, V. S.; Skasyrskaya, A. K.

    2016-10-01

    There is a proposal to search for a sterile neutrino in a few keV mass range by the "Troitsk nu-mass" facility. In order to estimate sterile neutrino mixing one needs to make precision spectrum measurements well below the endpoint using the existing electrostatic spectrometer with a magnetic adiabatic collimation, or MAC-E filter. The expected signature will be a kink in the electron energy spectrum in tritium beta-decay. In this paper we consider the systematic effect of electron backscattering on the detector used in the spectrometer. For this purpose we provide a set of Monte-Carlo simulation results of electron backscattering on a silicon detector with a thin golden window with realistic electric and magnetic fields in the spectrometer. We have found that the probability of such an effect reaches up to 20-30%. The scattered electron could be reflected backwards to the detector by electrostatic field or by magnetic mirror. There is also a few percent probability to escape from the spectrometer through its entrance. A time delay between the scattering on the detector and the return of the reflected electron can reach a couple of microseconds in the Troitsk spectrometer. Such estimations are critical for the planning upgrades of the detector and the registration electronics. All considered effects are relevant to any MAC-E type spectrometer with solid detector.

  1. Addressing Ozone Layer Depletion

    Science.gov (United States)

    Access information on EPA's efforts to address ozone layer depletion through regulations, collaborations with stakeholders, international treaties, partnerships with the private sector, and enforcement actions under Title VI of the Clean Air Act.

  2. Addressivity in cogenerative dialogues

    Science.gov (United States)

    Hsu, Pei-Ling

    2014-03-01

    Ashraf Shady's paper provides a first-hand reflection on how a foreign teacher used cogens as culturally adaptive pedagogy to address cultural misalignments with students. In this paper, Shady drew on several cogen sessions to showcase his journey of using different forms of cogens with his students. To improve the quality of cogens, one strategy he used was to adjust the number of participants in cogens. As a result, some cogens worked and others did not. During the course of reading his paper, I was impressed by his creative and flexible use of cogens and at the same time was intrigued by the question of why some cogens work and not others. In searching for an answer, I found that Mikhail Bakhtin's dialogism, especially the concept of addressivity, provides a comprehensive framework to address this question. In this commentary, I reanalyze the cogen episodes described in Shady's paper in the light of dialogism. My analysis suggests that addressivity plays an important role in mediating the success of cogens. Cogens with high addressivity function as internally persuasive discourse that allows diverse consciousnesses to coexist and so likely affords productive dialogues. The implications of addressivity in teaching and learning are further discussed.

  3. NOVEL MICROWAVE FILTER DESIGN TECHNIQUES.

    Science.gov (United States)

    ELECTROMAGNETIC WAVE FILTERS, MICROWAVE FREQUENCY, PHASE SHIFT CIRCUITS, BANDPASS FILTERS, TUNED CIRCUITS, NETWORKS, IMPEDANCE MATCHING , LOW PASS FILTERS, MULTIPLEXING, MICROWAVE EQUIPMENT, WAVEGUIDE FILTERS, WAVEGUIDE COUPLERS.

  4. TMAC: Timestamp-Ordered MAC Protocol for Wireless Mesh Networks

    KAUST Repository

    Nawab, Faisal

    2011-05-01

    Wireless Mesh Networks (WMNs) have emerged to meet a need for a self-organized and self-configured multi-hop wireless network infrastructure. Low cost infrastructure and ease of deployment have made WMNs an attractive technology for last mile access. However, 802.11 based WMNs are subject to serious fairness issues. With backlogged TCP traffic, nodes which are two or more hops away from the gateway are subject to starvation, while the one-hop away node saturates the channel with its own local traffic. We study the interactions of TCP and IEEE 802.11 MAC in WMNs to aid us in understanding and overcoming the unfairness problem. We propose a Markov chain to capture the behavior of TCP sessions, particularly the impact on network throughput performance due to the effect of queue utilization and packet relaying. A closed form solution is derived to numerically derive the throughput. Based on the developed model, we propose a distributed MAC protocol called Timestamp-ordered MAC (TMAC), aiming to alleviate the unfairness problem in WMNs via a manipulative per-node scheduling mechanism which takes advantage of the age of each packet as a priority metric. Simulation is conducted to validate our model and to illustrate the fairness characteristics of TMAC. Our results show that TMAC achieves excellent resource allocation fairness while maintaining above 90% of maximum link capacity in parking lot and large grid topologies. Our work illuminates the factors affecting TCP fairness in WMNs. Our theoretical and empirical findings can be used in future research to develop more fairness-aware protocols for WMNs.

  5. Miniaturized dielectric waveguide filters

    Science.gov (United States)

    Sandhu, Muhammad Y.; Hunter, Ian C.

    2016-10-01

    Design techniques for a new class of integrated monolithic high-permittivity ceramic waveguide filters are presented. These filters enable a size reduction of 50% compared to air-filled transverse electromagnetic filters with the same unloaded Q-factor. Designs for Chebyshev and asymmetric generalised Chebyshev filter and a diplexer are presented with experimental results for an 1800 MHz Chebyshev filter and a 1700 MHz generalised Chebyshev filter showing excellent agreement with theory.

  6. Tournament MAC with Constant Size Congestion Window for WLAN

    CERN Document Server

    Galtier, Jerome

    2007-01-01

    In the context of radio distributed networks, we present a generalized approach for the Medium Access Control (MAC) with fixed congestion window. Our protocol is quite simple to analyze and can be used in a lot of different situations. We give mathematical evidence showing that our performance is tight, in the sense that no protocol with fixed congestion window can do better. We also place ourselves in the WiFi/WiMAX framework, and show experimental results enlightening collision reduction of 14% to 21% compared to the best known other methods. We show channel capacity improvement, and fairness considerations.

  7. Dual Description of Supergravity MacDowell-Mansouri Theory

    CERN Document Server

    García-Compéan, H; Obregón, O; Ramírez, C

    1999-01-01

    In the context of field theory two elements seem to be necessary to search for strong-weak coupling duality. First, one needs a gauge theory and second, it should be supersymmetric. For gravitation these two elements are present in MacDowell-Mansouri supergravity. The search for an "effective duality" in this theory presents technical and conceptual problems that we discuss. Nevertheless, by means of a field theoretical approach, which in the abelian case coincides with $S$-duality, we exhibit a dual theory for supergravity, with inverted couplings. This results in a supersymmetric non-linear sigma model of the Freedman-Townsend type.

  8. Mac configuration management at the Los Alamos National Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Marcus, Allan B [Los Alamos National Laboratory

    2010-01-01

    The Los Alamos National Laboratory (LANL) had a need for central configuration management of non-Windows computers. LANL has three to five thousand Macs and an equal number of Linux based systems. The primary goal was to be able to inventory all non-windows systems and patch Mc OS X systems. LANL examined a number of commercial and open source solutions and ultimately selected Puppet. This paper will discuss why we chose Puppet, how we implemented it, and some lessons we learned along the way.

  9. Proximate analysis of coal by Leco MAC-400

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, S.T. (British Steel Corporation, London (UK). Ravenscraig Works)

    1988-01-01

    Discussion is presented of the use of the Leco Mac-400 Proximate Analyser at the Ravenscraig Steel Works, UK. It is used for the analysis of in-plant coals and the determination of ash in coke. The instrument does not meet the British Standard requirement for repeatability, so is not used for 'value in use' coal analysis. It has recently been overhauled, however, and will be re-evaluated to see if the overhaul has brought an improvement in performance. 6 figs., 7 tabs.

  10. Intelligent Cooperative MAC Protocol for Balancing Energy Consumption

    Science.gov (United States)

    Wu, S.; Liu, K.; Huang, B.; Liu, F.

    To extend the lifetime of wireless sensor networks, we proposed an intelligent balanced energy consumption cooperative MAC protocol (IBEC-CMAC) based on the multi-node cooperative transmission model. The protocol has priority to access high-quality channels for reducing energy consumption of each transmission. It can also balance the energy consumption among cooperative nodes by using high residual energy nodes instead of excessively consuming some node's energy. Simulation results show that IBEC-CMAC can obtain longer network lifetime and higher energy utilization than direct transmission.

  11. The role of electron scattering from registration detector in a MAC-E type spectrometer

    CERN Document Server

    Grigorieva, P V; Pantuev, V S; Skasyrskaya, A K

    2015-01-01

    There is a proposal to search for a sterile neutrino in a few keV mass range by the "Troitsk nu-mass" facility. In order to estimate sterile neutrino mixing one needs to make precision spectrum measurements well below the endpoint using the existing electrostatic spectrometer with a magnetic adiabatic collimation, or MAC-E filter. The expected signature will be a kink in the electron energy spectrum in tritium beta-decay. In this article we consider the systematic effect of electron backscattering on the detector used in the spectrometer. For this purpose we provide a set of Monte-Carlo simulation results of electron backscattering on a silicon detector with a thin golden window with realistic electric and magnetic fields in the spectrometer. We have found that the probability of such an effect reaches up to 20-30\\%. The scattered electron could be reflected backwards to the detector by electrostatic field or by magnetic mirror. There is also a few percent probability to escape from the spectrometer through i...

  12. Minimum alveolar concentration (MAC) for sevoflurane and xenon at normothermia and hypothermia in newborn pigs.

    Science.gov (United States)

    Liu, X; Dingley, J; Elstad, M; Scull-Brown, E; Steen, P A; Thoresen, M

    2013-05-01

    Neuroprotection from therapeutic hypothermia increases when combined with the anaesthetic gas xenon in animal studies. A clinical feasibility study of the combined treatment has been successfully undertaken in asphyxiated human term newborns. It is unknown whether xenon alone would be sufficient for sedation during hypothermia eliminating or reducing the need for other sedative or analgesic infusions in ventilated sick infants. Minimum alveolar concentration (MAC) of xenon is unknown in any neonatal species. Eight newborn pigs were anaesthetised with sevoflurane alone and then sevoflurane plus xenon at two temperatures. Pigs were randomised to start at either 38.5°C or 33.5°C. MAC for sevoflurane was determined using the claw clamp technique at the preset body temperature. For xenon MAC determination, a background of 0.5 MAC sevoflurane was used, and 60% xenon added to the gas mixture. The relationship between sevoflurane and xenon MAC is assumed to be additive. Xenon concentrations were changed in 5% steps until a positive clamp reaction was noted. Pigs' temperature was changed to the second target, and two MAC determinations for sevoflurane and 0.5 MAC sevoflurane plus xenon were repeated. MAC for sevoflurane was 4.1% [95% confidence interval (CI): 3.65-4.50] at 38.5°C and 3.05% (CI: 2.63-3.48) at 33.5°C, a significant reduction. MAC for xenon was 120% at 38.5°C and 116% at 33.5°C, not different. In newborn swine sevoflurane, MAC was temperature dependent, while xenon MAC was independent of temperature. There was large individual variability in xenon MAC, from 60% to 120%. © 2013 The Acta Anaesthesiologica Scandinavica Foundation.

  13. Astrometric sky survey of the zone +2° – +5.5° with the telescope MAC

    Science.gov (United States)

    Lazorenko, P.; Karbovsky, V.; Svachiy, L.; Buromsky, M.; Kasyan, S.

    2016-06-01

    We describe the results of the astrometric sky survey with the telescope MAC which was performed in 2010–2014 by the Main Astronomical observatory of NAS of Ukraine and Astronomical observatory of Taras Shevchenko Kiev national University. We obtained about 6 million of images of the sky objects to 17m in equatorial zone δ = +2°÷+5.5°. All images were obtained during 188 night observational series with use of V-band filter. Now we obtained the preliminary version of KMAC2.0 catalogue. We estimate that precision of positions for bright V<14m stars is 50–90 milliarcsecond and for fainter 14m

  14. Applications of nonwoven filter media

    Energy Technology Data Exchange (ETDEWEB)

    1988-11-01

    The multi-client technical and marketing report, Nonwovens in Filtration (1987) World Wide, has been completed by Filter Media Consulting, Inc. According to this 450-page report, $818 million in sales worldwide in nonwoven filter media represents a substantial segment of the entire nonwoven market. This total is mainly roll goods with a few exceptions. Meltblown composites represent $108 million, 13% of the total, and is the fastest growing segment as compared to needled felts, dry formed, thermobonded, spunbonded, wet laid and other unique processes, all extensively covered in this report. Included are 20 filtration applications covered in 190 pages, such as baghouse and dust filtration, Torit-type cartridge filters, HEPA/ULPA filtration, and heating, ventilation and air conditioning. Major markets are addressed, and trends in different fields are highlighted throughout the report.

  15. Sevoflurane decreases bispectral index values more than does halothane at equal MAC multiples.

    Science.gov (United States)

    Schwab, Hildebrand S; Seeberger, Manfred D; Eger, Edmond I; Kindler, Christoph H; Filipovic, Miodrag

    2004-12-01

    At the minimum alveolar concentration (MAC) of inhaled anesthetics, 50% of subjects move in response to noxious stimulation. Similarly, at MAC-awake, 50% of subjects respond appropriately to command. The bispectral index (BIS) nominally measures the effect of anesthetics on wakefulness or consciousness. We postulated that the use of halothane with a larger MAC-awake/MAC ratio than sevoflurane would produce higher BIS values at comparable levels of MAC. We studied 33 unpremedicated patients anesthetized by inhalation, 18 with sevoflurane and 15 with halothane. We measured BIS before and during anesthesia at 1 MAC, both before and after tracheal intubation facilitated by fentanyl and rocuronium and then at 1.5 MAC. BIS measurements were made after meeting steady-state conditions. No surgery was performed during this study. BIS values in awake patients did not differ between the sevoflurane and halothane groups (96 +/- 2 and 96 +/- 2, mean +/- sd, respectively). At 1 MAC without and with neuromuscular blockade and at 1.5 MAC, BIS values for patients anesthetized with halothane (54 +/- 7, 56 +/- 7, and 49 +/- 7, respectively) exceeded those for patients anesthetized with sevoflurane (34 +/- 6, 34 +/- 6, and 29 +/- 5, respectively) (P < 0.0001). This finding adds to other evidence indicating that BIS is drug specific.

  16. Power-Controlled MAC Protocols with Dynamic Neighbor Prediction for Ad hoc Networks

    Institute of Scientific and Technical Information of China (English)

    LI Meng; ZHANG Lin; XIAO Yong-kang; SHAN Xiu-ming

    2004-01-01

    Energy and bandwidth are the scarce resources in ad hoc networks because most of the mobile nodes are battery-supplied and share the exclusive wireless medium. Integrating the power control into MAC protocol is a promising technique to fully exploit these precious resources of ad hoc wireless networks. In this paper, a new intelligent power-controlled Medium Access Control (MAC) (iMAC) protocol with dynamic neighbor prediction is proposed. Through the elaborate design of the distributed transmit-receive strategy of mobile nodes, iMAC greatly outperforms the prevailing IEEE 802.11 MAC protocols in not only energy conservation but also network throughput. Using the Dynamic Neighbor Prediction (DNP), iMAC performs well in mobile scenes. To the best of our knowledge, iMAC is the first protocol that considers the performance deterioration of power-controlled MAC protocols in mobile scenes and then proposes a solution. Simulation results indicate that DNP is important and necessary for power-controlled MAC protocols in mobile ad hoc networks.

  17. An Empirical Study and some Improvements of the MiniMac Protocol for Secure Computation

    DEFF Research Database (Denmark)

    Damgård, Ivan Bjerre; Lauritsen, Rasmus; Toft, Tomas

    2014-01-01

    (nicknamed MiniMac). While TinyOT has already been implemented, we present in this paper the first implementation of MiniMac, using the same platform as the existing TinyOT implementation. We also suggest several improvements of MiniMac, both on the protocol design and implementation level. In particular, we...... suggest a modification of MiniMac that achieves increased parallelism at no extra communication cost. This gives an asymptotic improvement of the original protocol as well as an 8-fold speed-up of our implementation. We compare the resulting protocol to TinyOT for the case of secure computation in parallel...

  18. PA-MAC:A Passive Asynchronous MAC Protocol for Low Duty-Cycled Wireless Sensor Networks%PA-MAC:一种被动的异步低占空比无线传感器网络MAC协议

    Institute of Scientific and Technical Information of China (English)

    唐震洲; 施晓秋; 金可仲

    2011-01-01

    空闲侦听是无线传感器网络能耗的主要原因之一,而占空比机制是减少空闲侦听能量损耗最主要的方法之一.提出了一种新的无线传感器网络异步MAC协议,称为PA-MAC(Passive Asynchronous MAC),即被动异步MAC.PA-MAC通过采用接收方发起数据传输机制、异步占空比机制以及节点唤醒时间估计机制,降低了节点的工作占空比,提高了网络的能量有效性.在NS2网络仿真平台上对PA-MAC的性能进行了评估.仿真结果表明,在保持网络性能的前提下,PA-MAC能够进一步降低节点工作的占空比,进而减少节点的能耗.%The problem of idle listening is one of the most concerned issues in wireless sensor networks, and the duty cycling mechanism is widely used to reduce energy consumption. We present a new asynchronous MAC protocol, called Passive-Asynchronous MAC (PA-MAC). PA-MAC uses receiver-initiated data transmission scheme, asynchronous duty cycling mechanism and awakening time estimation scheme to achieve low duty cycle and high energy efficiency. Simulations have been done to evaluate the performance of the proposed new protocol, by which we can find out that,on the premise of keeping the network performance,PA-MAC can further reduce the nodes' duty cycle ,thereby reduce the energy consumption.

  19. Autonomous Power Control MAC Protocol for Mobile Ad Hoc Networks

    Directory of Open Access Journals (Sweden)

    2006-01-01

    Full Text Available Battery energy limitation has become a performance bottleneck for mobile ad hoc networks. IEEE 802.11 has been adopted as the current standard MAC protocol for ad hoc networks. However, it was developed without considering energy efficiency. To solve this problem, many modifications on IEEE 802.11 to incorporate power control have been proposed in the literature. The main idea of these power control schemes is to use a maximum possible power level for transmitting RTS/CTS and the lowest acceptable power for sending DATA/ACK. However, these schemes may degrade network throughput and reduce the overall energy efficiency of the network. This paper proposes autonomous power control MAC protocol (APCMP, which allows mobile nodes dynamically adjusting power level for transmitting DATA/ACK according to the distances between the transmitter and its neighbors. In addition, the power level for transmitting RTS/CTS is also adjustable according to the power level for DATA/ACK packets. In this paper, the performance of APCMP protocol is evaluated by simulation and is compared with that of other protocols.

  20. Learning Microsoft Excel 2011 for Mac video training DVD

    CERN Document Server

    Vaccaro, Guy

    2011-01-01

    In this video tutorial for Microsoft Excel 2011 For Mac, expert author Guy Vaccaro teaches you to effectively utilize the features and functions of Excel through project based learning. You will complete various projects, and along they way learn to leverage the power of the most important features Excel 2011 has to offer the Mac user. Starting your training course with the creation of a spreadsheet to record and monitor sales data, you will learn the basics of what you can do with a spreadsheet. You will then move on to creating a Profit and Loss report, learning formulas along the way. Moving to score sheets for a sports day, you will discover conditional based formatting, lookups, and more. You then create a functional expense claim form, advancing your Excel expertise. Moving on to a sales contact management sheet, you will discover how you can manipulate text, and even create mail merges from Excel. Finally, you will utilize all your knowledge thus far to create a sales report, including charts, pivot ta...

  1. MAC Layer Resource Allocation for Wireless Body Area Networks

    Institute of Scientific and Technical Information of China (English)

    Qinghua Shen; Xuemin Sherman Shen; Tom HLuan; Jing Liu

    2014-01-01

    Wireless body area networks (WBANs) can provide low-cost, timely healthcare services and are expected to be widely used for e-healthcare in hospitals. In a hospital, space is often limited and multiple WBANs have to coexist in an area and share the same channel in order to provide healthcare services to different patients. This causes severe interference between WBANs that could significantly reduce the network throughput and increase the amount of power consumed by sensors placed on the body. There-fore, an efficient channel-resource allocation scheme in the medium access control (MAC) layer is crucial. In this paper, we devel-op a centralized MAC layer resource allocation scheme for a WBAN. We focus on mitigating the interference between WBANs and reducing the power consumed by sensors. Channel and buffer state are reported by smartphones deployed in each WBAN, and channel access allocation is performed by a central controller to maximize network throughput. Sensors have strict limitations in terms of energy consumption and computing capability and cannot provide all the necessary information for channel allocation in a timely manner. This deteriorates network performance. We exploit the temporal correlation of the body area channel in order to minimize the number of channel state reports necessary. We view the network design as a partly observable optimization prob-lem and develop a myopic policy, which we then simulate in Matlab.

  2. A Review of MAC Scheduling Algorithms in LTE System

    Directory of Open Access Journals (Sweden)

    Satheesh Monikandan B

    2017-06-01

    Full Text Available The recent wireless communication networks rely on the new technology named Long Term Evolution (LTE to offer high data rate real-time (RT traffic with better Quality of Service (QoS for the increasing demand of customer requirement. LTE provide low latency for real-time services with high throughput, with the help of two-level packet retransmission. Hybrid Automatic Repeat Request (HARQ retransmission at the Medium Access Control (MAC layer of LTE networks achieves error-free data transmission. The performance of the LTE networks mainly depends on how effectively this HARQ adopted in the latest communication standard, Universal Mobile Telecommunication System (UMTS. The major challenge in LTE is to balance QoS and fairness among the users. Hence, it is very essential to design a down link scheduling scheme to get the expected service quality to the customers and to utilize the system resources efficiently. This paper provides a comprehensive literature review of LTE MAC layer and six types of QoS/Channel-aware downlink scheduling algorithms designed for this purpose. The contributions of this paper are to identify the gap of knowledge in the downlink scheduling procedure and to point out the future research direction. Based on the comparative study of algorithms taken for the review, this paper is concluded that the EXP Rule scheduler is most suited for LTE networks due to its characteristics of less Packet Loss Ratio (PLR, less Packet Delay (PD, high throughput, fairness and spectral efficiency.

  3. Conceptualizing ¬the Abstractions of Earthquakes Through an Instructional Sequence Using SeisMac and the Rapid Earthquake Viewer

    Science.gov (United States)

    Taber, J.; Hubenthal, M.; Wysession, M.

    2007-12-01

    Newsworthy earthquakes provide an engaging hook for students in Earth science classes, particularly when discussing their effects on people and the landscape. However, engaging students in an analysis of earthquakes that extends beyond death and damage, is frequently hampered by the abstraction of recorded ground motion data in the form of raw seismograms and the inability of most students to personally relate to ground accelerations. To overcome these challenges, an educational sequence has been developed using two software tools: SeisMac by Daniel Griscom, and the Rapid Earthquake Viewer (REV) developed by the University of South Carolina in collaboration with IRIS and DLESE. This sequence presents a unique opportunity for Earth Science teachers to "create" foundational experiences for students as they construction a framework of understanding of abstract concepts. The first activity is designed to introduce the concept of a three-component seismogram and to directly address the very abstract nature of seismograms through a kinesthetic experience. Students first learn to take the pulse of their classroom through a guided exploration of SeisMac, which displays the output of the laptop's built-in Sudden Motion Sensor (a 3-component accelerometer). This exploration allows students to view a 3-component seismogram as they move or tap the laptop and encourages them to propose and carry out experiments to explain the meaning of the 3-component seismogram. Once completed students are then asked to apply this new knowledge to a real 3-component seismogram printed from REV. Next the activity guides students through the process of identifying P and S waves and using SeisMac to connect the physical motion of the laptop to the "wiggles" they see on the SeisMac display and then comparing those to the "wiggles" they see on their seismogram. At this point students are more fully prepared to engage in an S-P location exercise such as those included in many state standards

  4. Filter quality of pleated filter cartridges.

    Science.gov (United States)

    Chen, Chun-Wan; Huang, Sheng-Hsiu; Chiang, Che-Ming; Hsiao, Ta-Chih; Chen, Chih-Chieh

    2008-04-01

    The performance of dust cartridge filters commonly used in dust masks and in room ventilation depends both on the collection efficiency of the filter material and the pressure drop across the filter. Currently, the optimization of filter design is based only on minimizing the pressure drop at a set velocity chosen by the manufacturer. The collection efficiency, an equally important factor, is rarely considered in the optimization process. In this work, a filter quality factor, which combines the collection efficiency and the pressure drop, is used as the optimization criterion for filter evaluation. Most respirator manufacturers pleat the filter to various extents to increase the filtration area in the limit space within the dust cartridge. Six sizes of filter holders were fabricated to hold just one pleat of filter, simulating six different pleat counts, ranging from 0.5 to 3.33 pleats cm(-1). The possible electrostatic charges on the filter were removed by dipping in isopropyl alcohol, and the air velocity is fixed at 100 cm s(-1). Liquid dicotylphthalate particles generated by a constant output atomizer were used as challenge aerosols to minimize particle loading effects. A scanning mobility particle sizer was used to measure the challenge aerosol number concentrations and size distributions upstream and downstream of the pleated filter. The pressure drop across the filter was monitored by using a calibrated pressure transducer. The results showed that the performance of pleated filters depend not only on the size of the particle but also on the pleat count of the pleated filter. Based on filter quality factor, the optimal pleat count (OPC) is always higher than that based on pressure drop by about 0.3-0.5 pleats cm(-1). For example, the OPC is 2.15 pleats cm(-1) from the standpoint of pressure drop, but for the highest filter quality factor, the pleated filter needed to have a pleat count of 2.65 pleats cm(-1) at particle diameter of 122 nm. From the aspect of

  5. Mac-1 deficiency induces respiratory failure by affecting type I alveolar epithelial cells.

    Science.gov (United States)

    Wang, J; Ci, Y B; Liu, C L; Sun, H M

    2017-08-31

    As a β2 integrin family member, Mac-1 plays an important role in the inflammatory response. Inflammation and lung injury are closely associated, but the involvement of Mac-1 in the occurrence and development of such pathologies remains poorly understood. We aimed to investigate the relationship between Mac-1 deficiency and respiratory failure in Mac-1 knockout {Mac-1(-/-)} mice, using C57BL/6J mice as a control. The newborn survival rate of Mac-1(-/-) mice was calculated, and mouse lung tissue was treated with hematoxylin and eosin and subjected to immunofluorescent staining. Moreover, western blotting and immunohistochemistry were used to detect the expression of molecules specific to type I and type II alveolar epithelial cells, as well as alveolar surfactant proteins secreted by the latter. Survival of Mac-1(-/-) pups was significantly lower than that of newborn C57BL/6J mice. In a float test, lung tissues from C57BL/6J mice were buoyant, whereas those of Mac-1(-/-) mice were not. Compared with C57BL/6J mice, expression of proSP-C {specific to type II alveolar epithelial cells} and alveolar surfactant proteins in Mac-1(-/-) mice was not significantly different, implying that type II cell function was unaltered. However, western blotting revealed expression of T1α, Aqp5, and Snx5 {type I alveolar epithelial cell markers} in Mac-1(-/-) mice to be significantly decreased {P Mac-1 may play an important role in respiratory failure. Its absence leads to this condition not by influencing type II alveolar epithelial cells or their secreted surfactant proteins, but rather by reducing type I alveolar cell numbers.

  6. Composing morphological filters

    NARCIS (Netherlands)

    H.J.A.M. Heijmans (Henk)

    1995-01-01

    textabstractA morphological filter is an operator on a complete lattice which is increasing and idempotent. Two well-known classes of morphological filters are openings and closings. Furthermore, an interesting class of filters, the alternating sequential filters, is obtained if one composes openin

  7. Composing morphological filters

    NARCIS (Netherlands)

    Heijmans, H.J.A.M.

    1995-01-01

    A morphological filter is an operator on a complete lattice which is increasing and idempotent. Two well-known classes of morphological filters are openings and closings. Furthermore, an interesting class of filters, the alternating sequential filters, is obtained if one composes openings and closi

  8. Passive Power Filters

    CERN Document Server

    Künzi, R

    2015-01-01

    Power converters require passive low-pass filters which are capable of reducing voltage ripples effectively. In contrast to signal filters, the components of power filters must carry large currents or withstand large voltages, respectively. In this paper, three different suitable filter struc tures for d.c./d.c. power converters with inductive load are introduced. The formulas needed to calculate the filter components are derived step by step and practical examples are given. The behaviour of the three discussed filters is compared by means of the examples. P ractical aspects for the realization of power filters are also discussed.

  9. Application of HollySys MACS DCS to PET plant%HollySys MACS DCS在PET装置中的应用

    Institute of Scientific and Technical Information of China (English)

    霍卫

    2015-01-01

    介绍了HollySys MACS DCS在PET装置中的应用,简要说明了PET装置的生产工艺和MACS系统的主要特点,介绍了该装置控制系统的软硬件构成,阐述了HollySys MACS DCS在PET装置中应用的控制方案.

  10. Addressing mathematics & statistics anxiety

    OpenAIRE

    Kotecha, Meena

    2015-01-01

    This paper should be of interest to mathematics and statistics educators ranging from pre-university to university education sectors. It will discuss some features of the author’s teaching model developed over her longitudinal study conducted to understand and address mathematics and statistics anxiety, which is one of the main barriers to engaging with these subjects especially in non-specialist undergraduates. It will demonstrate how a range of formative assessments are used to kindle, as w...

  11. Optimization and verification of the TR-MAC protocol for wireless sensor networks

    NARCIS (Netherlands)

    Morshed, Sarwar; Heijenk, Geert

    2015-01-01

    Energy-efficiency is an important requirement in the design of communication protocols for wireless sensor networks (WSN). TR-MAC is an energy-efficient medium access control (MAC) layer protocol for low power WSN that exploits transmitted-reference (TR) modulation in the physical layer. The underly

  12. Official Portrait of STS-52 Canadian Payload Specialist Steve G. MacLean

    Science.gov (United States)

    1992-01-01

    STS-52 Canadian Payload Specialist Steven G. MacLean, wearing a launch and entry suit (LES), poses with a launch and entry helmet (LEH) and Canadian flag for his Official portrait. MacLean representing the Canadian Space Agency (CSA) will fly aboard Columbia, Orbiter Vehicle (OV) 102, for the STS-52 mission.

  13. Transcriptomic microarray analysis of BoMac cells after infection with bovine foamy virus

    NARCIS (Netherlands)

    Rola-Luszczak, M.; Materniak, M.; Pluta, A.; Hulst, M.M.; Kuz'mak, J.

    2014-01-01

    Bovine foamy virus (BFV) infections are highly prevalent among cattle worldwide. However, relatively little is known about the impact of this virus on the host immune system. In our study, we focused on a bovine macrophage cell line (BoMac) and examined changes in the BoMac transcriptome after in vi

  14. Scheduled MAC in Beacon Overlay Networks for Underwater Localization and Time-Synchronization

    NARCIS (Netherlands)

    van Kleunen, W.A.P.; Meratnia, Nirvana; Havinga, Paul J.M.

    2011-01-01

    In this article we introduce a MAC protocol designed for underwater localization and time-synchronisation. The MAC protocol assumes a network of static reference nodes and allows blind nodes to be localized by listening-only to the beacon messages. Such a system is known to be very scalable. We show

  15. Simulation of 64-bit MAC Unit using Kogge Stone Adder and Ancient Indian Mathematics

    Directory of Open Access Journals (Sweden)

    Aapurva Kaul

    2016-05-01

    Full Text Available This paper describes that multiply and accumulate (MAC unit plays a very vital role in various Digital Signal Processing applications. Speed of these applications depends on the speed of these three sub units of MAC multiply unit, adder unit and accumulator unit. In this paper the delay of 64-bit MAC unit is decreased as compared to the previous MAC units. In this Kogge Stone Adder is used as adder in design Vedic Multiplier using Urdhva Tiryakbhyam sutra. The designing of MAC unit is done under VIRTEX-4 family, XC4VFX140 device, FF1517 package and -11 speed and comparison of proposed MAC unit design is done under SPARTAN- 3E family, XC3S500 device, FG320 package and -5 speed in Xilinx ISE 8.1i. The combinational path delay of the 64-bit MAC unit is 59.705ns in SPARTAN-3E family. Ancient Indian mathematics is being used for designing of multiplier unit to decrease the overall delay of the MAC unit.

  16. A concurrent access MAC protocol for cognitive radio ad hoc networks without common control channel

    Science.gov (United States)

    Timalsina, Sunil K.; Moh, Sangman; Chung, Ilyong; Kang, Moonsoo

    2013-12-01

    Cognitive radio ad hoc networks (CRAHNs) consist of autonomous nodes that operate in ad hoc mode and aim at efficient utilization of spectrum resources. Usually, the cognitive nodes in a CRAHN exploit a number of available channels, but these channels are not necessarily common to all nodes. Such a network environment poses the problem of establishing a common control channel (CCC) as there might be no channel common to all the network members at all. In designing protocols, therefore, it is highly desirable to consider the network environment with no CCC. In this article, we propose a MAC protocol called concurrent access MAC (CA-MAC) that operates in the network environment with no CCC. The two devices in a communication pair can communicate with each other even if they have only one common channel available. Therefore, the problems with CCC (such as channel saturation and denial of service attacks) can also be resolved. In CA-MAC, channel accesses are distributed over communication pairs, resulting in increased network connectivity. In addition, CA-MAC allows different communication pairs to access multiple channels concurrently. According to our performance study, CA-MAC provides higher network connectivity with shorter channel access delay compared to SYN-MAC, which is the conventional key MAC protocol for the network environment with no CCC, resulting in better network throughput.

  17. Investigation of Mycobacterium avium complex (MAC) in Australian commercial milk using qPCR.

    Science.gov (United States)

    Adhikari, Shraddha; Caro Tohme, Tanya; Whiley, Harriet

    2017-02-01

    This technical research communication describes the first study to use quantitative polymerase chain reaction (qPCR) to investigate the presence of Mycobacterium avium complex (MAC) in Australian pasteurised milk. MAC is the most common NTM responsible for human illnesses and includes M. avium subspecies paratuberculosis (MAP). MAC is a causative agent of lymphadenitis in children, with contaminated food and water considered as a likely source. As such the presence of MAC in milk would have public health significance. MAP has been linked to Crohn's disease and is also the causative agent of Johne's disease in cattle. Previous studies have detected MAP in pasteurised milk from Brazil, India, Czech Republic, USA, Argentina, UK, Iran, Ireland and the United Kingdom. This study investigated a total of 180 commercially available Australian pasteurised milk samples which were tested for MAC DNA in triplicate using PCR. All samples were negative for MAC DNA. An additional 14 milk samples were tested, incubated for 3 weeks at 37 °C to potentially increase the concentration of any viable MAC that may be present and then retested. All samples were again negative for MAC DNA. This could be due to concentrations below the limit of detection, limited sample size or could be reflective of the Australian biosecurity control protocols and surveillance of Johne's disease in ruminant animals.

  18. An update on the side channel cryptanalysis of MACs based on cryptographic hash functions

    DEFF Research Database (Denmark)

    Gauravaram, Praveen; Okeya, Katsuyuki

    2007-01-01

    into consideration. Next, we propose new hybrid NMAC/HMAC schemes for security against side channel attacks assuming that their underlying block cipher is ideal. We then show that M-NMAC, MDx-MAC and a variant of the envelope MAC scheme based on DM with an ideal block cipher are secure against DPA attacks....

  19. THE EFFECT OF TEMPERATURE ON THE GROWTH OF MYCOBACTERIUM AVIUM COMPLEX (MAC) ORGANISMS

    Science.gov (United States)

    MAC organisms are able to grow, persist, and colonize in water distribution systems and may amplify in hospital hot water systems. This study examined the response of MAC organisms (M. avium, M. intracellulare, and MX) to a range of temperatures commonly associated with drinking...

  20. Sevoflurane at 1 MAC provides optimal myocardial protection during off-pump CABG.

    Science.gov (United States)

    Wang, Jiang; Zheng, Hong; Chen, Chun-Ling; Lu, Wei; Zhang, Yong-Qiang

    2013-06-01

    We investigated the myocardial protective effect of sevoflurane in patients receiving off-pump coronary artery bypass grafting (OPCABG) and the role of brain natriuretic peptide (BNP). Forty-eight patients receiving elective OPCABG were randomly assigned to a control group, and to 0.75 MAC, 1.0 MAC and 1.5 MAC sevoflurane groups. Blood samples were collected and levels of BNP and cardiac troponin I (cTnI) were measured before anesthesia, and immediately, 24, 48 and 72 h after surgery. Dopamine was necessary to maintain blood pressure in the sevoflurane groups, but not in the control group (p MAC sevoflurane significantly decreased post-surgical cTnI levels (p MAC had no significant effect, and increasing sevoflurane concentrations to 1.5 MAC caused no further decrease in cTnI concentrations. There was no significant difference in BNP level among the groups (p = 0.227) or between any two groups, although values of BNP showed a significant correlation with cTnI values in control subjects immediately after (r = 0.847) and 24 h after (r = 0.661) surgery. Our results demonstrated that 1.0 MAC and 1.5 MAC sevoflurane can exert a significant myocardial protective effect. BNP cannot be used to predict the myocardial protective effect of sevoflurane in OPCABG.

  1. THE EFFECT OF TEMPERATURE ON THE GROWTH OF MYCOBACTERIUM AVIUM COMPLEX (MAC) ORGANISMS

    Science.gov (United States)

    MAC organisms are able to grow, persist, and colonize in water distribution systems and may amplify in hospital hot water systems. This study examined the response of MAC organisms (M. avium, M. intracellulare, and MX) to a range of temperatures commonly associated with drinking...

  2. Poincaré-MacMillan Equations of Motion for a Nonlinear Nonholonomic Dynamical System

    Institute of Scientific and Technical Information of China (English)

    Amjad Hussain; Syed Tauseef Mohyud-Din; Ahmet Yildirim

    2012-01-01

    MacMillan's equations are extended to Poincaré's formalism,and MacMillan's equations for nonlinear nonholonomic systems are obtained in terms of Poincaré parameters.The equivalence of the results obtained here with other forms of equations of motion is demonstrated.An illustrative example of the theory is provided as well.

  3. Un poste consulaire en Macédoine, Bitola-Monastir, 1851-1912

    Directory of Open Access Journals (Sweden)

    Bernard Lory

    2011-12-01

    Full Text Available Les consuls, plus détachés des nationalismes locaux, rendent compte des réalités sociales, culturelles et politiques de Bitola entre 1851 et 1912.L’article tente de restituer, à partir des archives consulaires de la ville macédonienne de Bitola, entre 1851 et 1912, une réalité sociale et culturelle de la Macédoine, moins filtrée par les idéologies nationales que celle que traduit la documentation interne en langues balkaniques. La plus grande partie des informations fournies par les correspondances consulaires provient des drogmans, interprètes assurant l’interface entre les autorités locales ottomanes et les consuls, mais les consuls s’informent aussi les uns les autres. À partir des années 1890, les questions politiques détrônent les intérêts économiques. Même si les historiens macédoniens de Bitola soulignent le rôle modernisateur des consuls, le corps consulaire y est trop restreint et replié sur lui-même pour exercer une influence significative. L’article analyse l’action politique des différents consulats. Ceux des États balkaniques organisent la subversion contre le pouvoir ottoman, ceux d’Autriche-Hongrie et de Russie, pays ayant des intérêts immédiats dans la zone balkanique, interviennent dans les affaires locales, officiellement ou de façon occulte, tandis que le rôle de ceux de Grande-Bretagne, d’Italie et de France est de maintenir le statut de Grande Puissance de ces pays.The article attempts to restore, starting with the consular archives of the Macedonian city of Bitola, between 1851 and 1912, a social and cultural reality of Macedonia, less filtered by the national ideologies than that which translates the internal documentation into Balkan languages. The greatest part of the information furnished by the consular correspondences derives from drogmans, interpretors assuring the interface between the local Ottoman authorities and the consuls, but the consuls also inform one another

  4. Adaptive Filtering Algorithms and Practical Implementation

    CERN Document Server

    Diniz, Paulo S R

    2013-01-01

    In the fourth edition of Adaptive Filtering: Algorithms and Practical Implementation, author Paulo S.R. Diniz presents the basic concepts of adaptive signal processing and adaptive filtering in a concise and straightforward manner. The main classes of adaptive filtering algorithms are presented in a unified framework, using clear notations that facilitate actual implementation. The main algorithms are described in tables, which are detailed enough to allow the reader to verify the covered concepts. Many examples address problems drawn from actual applications. New material to this edition includes: Analytical and simulation examples in Chapters 4, 5, 6 and 10 Appendix E, which summarizes the analysis of set-membership algorithm Updated problems and references Providing a concise background on adaptive filtering, this book covers the family of LMS, affine projection, RLS and data-selective set-membership algorithms as well as nonlinear, sub-band, blind, IIR adaptive filtering, and more. Several problems are...

  5. On PHY and MAC Performance in Body Sensor Networks

    Directory of Open Access Journals (Sweden)

    Sana Ullah

    2009-01-01

    Full Text Available This paper presents an empirical investigation on the performance of body implant communication using radio frequency (RF technology. In body implant communication, the electrical properties of the body influence the signal propagation in several ways. We use a Perspex body model (30 cm diameter, 80 cm height and 0.5 cm thickness filled with a liquid that mimics the electrical properties of the basic body tissues. This model is used to observe the effects of body tissue on the RF communication. We observe best performance at 3cm depth inside the liquid. We further present a simulation study of several low-power MAC protocols for an on-body sensor network and discuss the derived results. Also, the traditional preamble-based TMDA protocol is extended towards a beacon-based TDMA protocol in order to avoid preamble collision and to ensure low-power communication.

  6. Self and Otherness in Norman MacCaig’s Poetry

    Directory of Open Access Journals (Sweden)

    Dominique DELMAIRE

    2004-10-01

    Full Text Available No other Scottish poet has concerned himself more thoroughly than Norman MacCaig (1910-1996 — the author of such poems as “Ego,” “Other Self,” “Other self, same self,” and many more in the same vein — with the problematic issue of the subject and his relations to both reality and to his own multiple avatars or projections. “Other self” (Collected Poems 95 is such a case in point that it deserves full quoting:       My inmost creature, Caliban perhaps,      Perhaps St Francis (at least, a s...

  7. A Distributed MAC Protocol for Cooperation in Random Access Networks

    CERN Document Server

    Böcherer, Georg

    2008-01-01

    WLAN is one of the most successful applications of wireless communications in daily life because of low cost and ease of deployment. The enabling technique for this success is the use of random access schemes for the wireless channel. Random access requires minimal coordination between the nodes, which considerably reduces the cost of the infrastructure. Recently, cooperative communication in wireless networks has been of increasing interest because it promises higher rates and reliability. An additional MAC overhead is necessary to coordinate the nodes to allow cooperation and this overhead can possibly cancel out the cooperative benefits. In this work, a completely distributed protocol is proposed that allows nodes in the network to cooperate via Two-Hop and Decode-and-Forward for transmitting their data to a common gateway node. It is shown that high throughput gains are obtained in terms of the individual throughput that can be guaranteed to any node in the network. These results are validated by Monte Ca...

  8. Analysis and improvement of the MAC shaping mechanism in RPR

    Science.gov (United States)

    Li, Jing; Xu, Zhanqi; Yu, Shaohua

    2005-11-01

    Resilient Packet Ring (RPR) specified by IEEE 802.17 is a new standard for Metropolitan Area Networks (MANs). One of RPR's characteristics is that it can support three priorities traffic in a single datapath, i.e., class A, class B and class C, ranging from high priority to low priority, respectively. Different entities such as shaping, scheduling, fairness, topology and protection coordinate to guarantee the Quality of Service (QoS) for different services. Various pieces of the datapath in RPR are tied together through logical queues, thus we investigate the datapath from the view of logical queues in this paper. With a detailed analysis of the MAC shaping mechanism in RPR, we propose some improvement to achieve better transport performance for RPR's three priorities traffic. Simulation results show that our improvement is efficient.

  9. Marielle Macé, Le genre littéraire

    OpenAIRE

    2012-01-01

    Pour des termes génériques associés à une longue tradition et plusieurs écoles de pensée, la collection Corpus s’engage à présenter un panorama de définitions. Tel a été le cas, entre autres notions, pour celles d’auteur, de lecteur… L’ouvrage de Marielle Macé traite lui aussi d’une notion clé qui est au cœur d’une histoire plus que millénaire de la réflexion littéraire, mais aussi philosophique, voire linguistique et rhétorique, exposée aux vagues successives de remise en cause de la moderni...

  10. [Materials for the substantiation of the biological MAC of benzene].

    Science.gov (United States)

    Ulanova, I P; Avilova, G G; Karpukhina, E A; Karimova, L K; Boĭko, V I; Makar'eva, L M

    1990-09-01

    Relatively great amount of benzene-originated phenol, the presence of a definite relationship between phenol amount in the urine and benzene content in the air indicate that it is reasonable to use a phenol sample as an exposure test. To determine the intensity of benzene exposure, data on phenol content in the urine of people working at some big-tonnage enterprises has been analyzed. On the basis of the national and foreign literature data on the correlation between the phenol urine concentration and the level of benzene exposure a regression equation was deduced, which has made it possible to calculate phenol content in the urine on the level of average working day benzene concentration adopted in the USSR. This value equals 15 mg/l, which was proposed as a biological benzene MAC.

  11. MacBurn's cylinder test problem

    Energy Technology Data Exchange (ETDEWEB)

    Shestakov, Aleksei I. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2016-02-29

    This note describes test problem for MacBurn which illustrates its performance. The source is centered inside a cylinder with axial-extent-to-radius ratio s.t. each end receives 1/4 of the thermal energy. The source (fireball) is modeled as either a point or as disk of finite radius, as described by Marrs et al. For the latter, the disk is divided into 13 equal area segments, each approximated as a point source and models a partially occluded fireball. If the source is modeled as a single point, one obtains very nearly the expected deposition, e.g., 1/4 of the flux on each end and energy is conserved. If the source is modeled as a disk, both conservation and energy fraction degrade. However, errors decrease if the source radius to domain size ratio decreases. Modeling the source as a disk increases run-times.

  12. Sabine MacCormack, On the Wings of Time. Rome,

    OpenAIRE

    Rey, Sarah

    2011-01-01

    Que vient faire une antiquisante sur les hauteurs andines ? Sabine MacCormack, spécialiste de l’art romain, n’a pas à se justifier. Dans cette étude, l’abondante littérature qu’elle offre au lecteur suffit à prouver l’intérêt de sa démarche qui consiste à quêter les formes, les mots et les images de l’Antiquité apposés sur l’espace inca au moment de sa découverte. L’historienne donne une suite à son étude de 1991, Religion in the Andes  : Vision and Imagination in Early Colonial Peru. Pour re...

  13. MACS low-background doubly focusing neutron monochromator

    CERN Document Server

    Smee, S A; Scharfstein, G A; Qiu, Y; Brand, P C; Anand, D K; Broholm, C L

    2002-01-01

    A novel doubly focusing neutron monochromator has been developed as part of the Multi-Analyzer Crystal Spectrometer (MACS) at the NIST Center for Neutron Research. The instrument utilizes a unique vertical focusing element that enables active vertical and horizontal focusing with a large, 357-crystal (1428 cm sup 2), array. The design significantly reduces the amount of structural material in the beam path as compared to similar instruments. Optical measurements verify the excellent focal performance of the device. Analytical and Monte Carlo simulations predict that, when mounted at the NIST cold-neutron source, the device should produce a monochromatic beam (DELTA E=0.2 meV) with flux phi>10 sup 8 n/cm sup 2 s. (orig.)

  14. Antimoulting Activity of Eremanthus erythropappus (DC. MacLeisch

    Directory of Open Access Journals (Sweden)

    Danielle Barbosa

    2012-06-01

    Resumo. Os extratos e metabólitos secundários de plantas podem agir como agentes tóxicos e inibidores do da alimentação e do desenvolvimento em insetos. Neste estudo foi utilizado Oncopeltus fasciatus (Dallas (Hemiptera como modelo experimental a fim de avaliar as atividades do extrato etanólico bruto e frações obtidos das flores ou caules de Eremanthus erythropappus (DC. MacLeisch (Asteraceae, na mortalidade e sobre o desenvolvimento do inseto. A fração butanólica obtida do extrato etanólico mostrou toxidade sobre as ninfas de O. fasciatus, bem como atividade de inibição do crescimento. Os resultados sugerem que a fração butanólica de E. erythropappus possui substâncias ativas sobre a fisiologia, crescimento e desenvolvimento de insetos.

  15. On PHY and MAC Performance in Body Sensor Networks

    Directory of Open Access Journals (Sweden)

    Higgins Henry

    2009-01-01

    Full Text Available Abstract This paper presents an empirical investigation on the performance of body implant communication using radio frequency (RF technology. In body implant communication, the electrical properties of the body influence the signal propagation in several ways. We use a Perspex body model (30 cm diameter, 80 cm height and 0.5 cm thickness filled with a liquid that mimics the electrical properties of the basic body tissues. This model is used to observe the effects of body tissue on the RF communication. We observe best performance at 3cm depth inside the liquid. We further present a simulation study of several low-power MAC protocols for an on-body sensor network and discuss the derived results. Also, the traditional preamble-based TMDA protocol is extended towards a beacon-based TDMA protocol in order to avoid preamble collision and to ensure low-power communication.

  16. MAC Protocols for GSP in Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Maria Calle

    2008-06-01

    Full Text Available The Gossip-based Sleep Protocol (GSP is a routing protocol designed to save energy in Wireless Sensor Networks. This work presents two MAC protocols designed to complement the characteristics of GSP: MACGSP1 and MACGSP2 were evaluated in combination with GSP on square grids of 100, 400 and 900 simulated nodes. Both protocols show increased energy savings compared to GSP by itself. MACGSP1 provided the greatest energy savings, however MACGSP2 exhibited the best trade off between overhead, delay and packet reception probability. MACGSP2 reduces the duplicate packets generated by GSP, with no significant difference in end-to end delay and a reduced GSP packet reception probability of 10%.

  17. Interference Analysis Status and Plans for Aeronautical Mobile Airport Communications System (AeroMACS)

    Science.gov (United States)

    Kerczewski, Robert J.; Wilson, Jeffrey D.

    2010-01-01

    Interference issues related to the operation of an aeronautical mobile airport communications system (AeroMACS) in the C-Band (specifically 5091-5150 MHz) is being investigated. The issue of primary interest is co-channel interference from AeroMACS into mobile-satellite system (MSS) feeder uplinks. The effort is focusing on establishing practical limits on AeroMACS transmissions from airports so that the threshold of interference into MSS is not exceeded. The analyses are being performed with the software package Visualyse Professional, developed by Transfinite Systems Limited. Results with omni-directional antennas and plans to extend the models to represent AeroMACS more accurately will be presented. These models should enable realistic analyses of emerging AeroMACS designs to be developed from NASA Test Bed, RTCA 223, and European results.

  18. Reliable Multicast MAC Protocol for IEEE 802.11 Wireless LANs with Extended Service Range

    Science.gov (United States)

    Choi, Woo-Yong

    2011-11-01

    In this paper, we propose the efficient reliable multicast MAC protocol by which the AP (Access Point) can transmit reliably its multicast data frames to the recipients in the AP's one-hop or two-hop transmission range. The AP uses the STAs (Stations) that are directly associated with itself as the relays for the data delivery to the remote recipients that cannot be reached directly from itself. Based on the connectivity information among the recipients, the reliable multicast MAC protocol optimizes the number of the RAK (Request for ACK) frame transmissions in a reasonable computational time. Numerical examples show that our proposed MAC protocol significantly enhances the MAC performance compared with the BMMM (Batch Mode Multicast MAC) protocol that is extended to support the recipients that are in the AP's one-hop or two-hop transmission range in IEEE 802.11 wireless LANs.

  19. The identification of MacSe in Streptococcus equi ssp. equi

    Institute of Scientific and Technical Information of China (English)

    Jiande YANG; Yanfei LIU; Jun XU; Jifei MA

    2009-01-01

    Streptococcus equi subsp, equi (S. equi ssp. equi) causes equine strangles, a highly contagious and widespread purulent lymphadenitis of the head and neck. We have identified MacSe, a novel protein of S. equi, by screening a phage library of 3-8 kb random DNA fragments of S. equi CF32. MacSe shares 62% and 67.5% amino acid homology with Mac5005 and Mac8345 of S. pyogenes respectively. Expression during infection was shown by strong reactivity of the protein with convalescent sera and mucosal wash IgA of ponies infected by commingling exposure. Release into the culture medium was detected during the log phase of growth. Dose dependent anti-phagocytic activity for equine neutrophils involved interaction of MacSe with C3 and neutrophils.

  20. Self-Adaptive and Energy-Efficient MAC Protocol Based on Event-Driven

    Directory of Open Access Journals (Sweden)

    Xin Hou

    2013-01-01

    Full Text Available Combined with WSN MAC layer protocol characteristics and design requirements, according to the characteristic of WSN monitoring application requirements, this paper puts forward a method based on event driven MAC protocol. The agreement algorithm is to solve the problem of network congestion and node energy unnecessary consumption cause by a large number of redundant monitoring data transceiver. It is a kind of adaptive low power consumption of the MAC layer protocol, which is pointed out based on theoretical foundation of S_MAC protocol, made use of the event driven mechanism system theory, combined with event driven mechanism and the characteristics of the WSN. It has the periodic dormancy mechanism of S_MAC protocol, in the premise of the reliability data, to reduce data redundancy and communication delay time, improve the overall network throughput, to ensure the safety and reliability of the network, which can greatly extends  the node of working time.

  1. Energy efficient TDMA-based MAC protocol associated with GAF for wireless sensor networks

    Institute of Scientific and Technical Information of China (English)

    XIAO Xiao; ZHENG Bao-yu; YAN Zhen-ya; CHEN Chao

    2007-01-01

    The design of media access control (MAC) protocol for wireless sensor networks (WSNs) with the idea of cross layer attracts more and more attention. People can improve the MAC protocol by obtaining certain information regarding the network layer and physical layer. This article synthesizes and optimizes certain cross-layer protocols which have existed. On the basis of the routing, topology information in the network layer, and transmission power information in the physical layer, the time slot assignment algorithm has been improved in the MAC layer.By using geographical adaptive fidelity algorithm (GAF) to divide the grids, controlling of transmission power and scheduling the work/sleep duty cycle for sensor nodes, a new MAC protocol has been proposed to decrease energy consumption and enlarge the lifetime of WSNs. Simulation results show that the MAC protocol functions well.

  2. Research on low-latency MAC protocols for wireless sensor networks

    Science.gov (United States)

    He, Chenguang; Sha, Xuejun; Lee, Chankil

    2007-11-01

    Energy-efficient should not be the only design goal in MAC protocols for wireless sensor networks, which involve the use of battery-operated computing and sensing devices. Low-latency operation becomes the same important as energy-efficient in the case that the traffic load is very heavy or the real-time constrain is used in applications like tracking or locating. This paper introduces some causes of traditional time delays which are inherent in a multi-hops network using existing WSN MAC protocols, illuminates the importance of low-latency MAC design for wireless sensor networks, and presents three MACs as examples of low-latency protocols designed specially for sleep delay, wait delay and wakeup delay in wireless sensor networks, respectively. The paper also discusses design trade-offs with emphasis on low-latency and points out their advantages and disadvantages, together with some design considerations and suggestions for MAC protocols for future applications and researches.

  3. An Energy-Efficient, Application-Oriented Control Algorithm for MAC Protocols in WSN

    Science.gov (United States)

    Li, Deliang; Peng, Fei; Qian, Depei

    Energy efficiency has been a main concern in wireless sensor networks where Medium Access Control (MAC) protocol plays an important role. However, current MAC protocols designed for energy saving have seldom considered multiple applications coexisting in WSN with variation of traffic load dynamics and different QoS requirements. In this paper, we propose an adaptive control algorithm at MAC layer to promote energy efficiency. We focus on the tradeoff relation between collisions and control overhead as a reflection of traffic load and propose to balance the tradeoff under the constraints of QoS options. We integrate the algorithm into S-MAC and verify it through NS-2 platform. The results demonstrate the algorithm achieves observable improvement in energy performance while meeting QoS requirement for different coexisting applications in comparison with S-MAC.

  4. MAQF/MAC:A New QoS Provisioning MAC Mechanism for MANET

    Institute of Scientific and Technical Information of China (English)

    YAOYinxion; WANGHaoxing; WANXiang

    2003-01-01

    QoS provisioning is not an easy problem under the time varying and dynamic environment of MANET.Based on MANET Adaptive QoS Framework(MAQF)and through improving the scheme of MACA/PR,a new mechanism MAQF/MAC that can provide MAC layer QoS guarantees for MANET has been presented.MAQF/MAC can measure the variation of resource in real time,change the channel access policy and adapt the amount of resource captured by trafflc.In addition,this paper also concerns some key components of MAQF/MAC,including reservation table(RT),QoS routing,resource compression algorithm and etc.Simulation result show that MAQF/MAC ls superior to MACA/PR in the aspects of multi-level trafflc QoS provisioning and resource utilization.

  5. MicMac GIS application: free open source

    Science.gov (United States)

    Duarte, L.; Moutinho, O.; Teodoro, A.

    2016-10-01

    The use of Remotely Piloted Aerial System (RPAS) for remote sensing applications is becoming more frequent as the technologies on on-board cameras and the platform itself are becoming a serious contender to satellite and airplane imagery. MicMac is a photogrammetric tool for image matching that can be used in different contexts. It is an open source software and it can be used as a command line or with a graphic interface (for each command). The main objective of this work was the integration of MicMac with QGIS, which is also an open source software, in order to create a new open source tool applied to photogrammetry/remote sensing. Python language was used to develop the application. This tool would be very useful in the manipulation and 3D modelling of a set of images. The main objective was to create a toolbar in QGIS with the basic functionalities with intuitive graphic interfaces. The toolbar is composed by three buttons: produce the points cloud, create the Digital Elevation Model (DEM) and produce the orthophoto of the study area. The application was tested considering 35 photos, a subset of images acquired by a RPAS in the Aguda beach area, Porto, Portugal. They were used in order to create a 3D terrain model and from this model obtain an orthophoto and the corresponding DEM. The code is open and can be modified according to the user requirements. This integration would be very useful in photogrammetry and remote sensing community combined with GIS capabilities.

  6. Mac-1 Regulates IL-13 Activity in Macrophages by Directly Interacting with IL-13Rα1.

    Science.gov (United States)

    Cao, Chunzhang; Zhao, Juanjuan; Doughty, Emily K; Migliorini, Mary; Strickland, Dudley K; Kann, Maricel G; Zhang, Li

    2015-08-28

    Mac-1 exhibits a unique inhibitory activity toward IL-13-induced JAK/STAT activation and thereby regulates macrophage to foam cell transformation. However, the underlying molecular mechanism is unknown. In this study, we report the identification of IL-13Rα1, a component of the IL-13 receptor (IL-13R), as a novel ligand of integrin Mac-1, using a co-evolution-based algorithm. Biochemical analyses demonstrated that recombinant IL-13Rα1 binds Mac-1 in a purified system and supports Mac-1-mediated cell adhesion. Co-immunoprecipitation experiments revealed that endogenous Mac-1 forms a complex with IL-13Rα1 in solution, and confocal fluorescence microscopy demonstrated that these two receptors co-localize with each other on the surface of macrophages. Moreover, we found that genetic inactivation of Mac-1 promotes IL-13-induced JAK/STAT activation in macrophages, resulting in enhanced polarization along the alternative activation pathway. Importantly, we observed that Mac-1(-/-) macrophages exhibit increased expression of foam cell differentiation markers including 15-lipoxygenase and lectin-type oxidized LDL receptor-1 both in vitro and in vivo. Indeed, we found that Mac-1(-/-)LDLR(-/-) mice develop significantly more foam cells than control LDLR(-/-) mice, using an in vivo model of foam cell formation. Together, our data establish for the first time a molecular mechanism by which Mac-1 regulates the signaling activity of IL-13 in macrophages. This newly identified IL-13Rα1/Mac-1-dependent pathway may offer novel targets for therapeutic intervention in the future.

  7. Mac-1 Regulates IL-13 Activity in Macrophages by Directly Interacting with IL-13Rα1*

    Science.gov (United States)

    Cao, Chunzhang; Zhao, Juanjuan; Doughty, Emily K.; Migliorini, Mary; Strickland, Dudley K.; Kann, Maricel G.; Zhang, Li

    2015-01-01

    Mac-1 exhibits a unique inhibitory activity toward IL-13-induced JAK/STAT activation and thereby regulates macrophage to foam cell transformation. However, the underlying molecular mechanism is unknown. In this study, we report the identification of IL-13Rα1, a component of the IL-13 receptor (IL-13R), as a novel ligand of integrin Mac-1, using a co-evolution-based algorithm. Biochemical analyses demonstrated that recombinant IL-13Rα1 binds Mac-1 in a purified system and supports Mac-1-mediated cell adhesion. Co-immunoprecipitation experiments revealed that endogenous Mac-1 forms a complex with IL-13Rα1 in solution, and confocal fluorescence microscopy demonstrated that these two receptors co-localize with each other on the surface of macrophages. Moreover, we found that genetic inactivation of Mac-1 promotes IL-13-induced JAK/STAT activation in macrophages, resulting in enhanced polarization along the alternative activation pathway. Importantly, we observed that Mac-1−/− macrophages exhibit increased expression of foam cell differentiation markers including 15-lipoxygenase and lectin-type oxidized LDL receptor-1 both in vitro and in vivo. Indeed, we found that Mac-1−/−LDLR−/− mice develop significantly more foam cells than control LDLR−/− mice, using an in vivo model of foam cell formation. Together, our data establish for the first time a molecular mechanism by which Mac-1 regulates the signaling activity of IL-13 in macrophages. This newly identified IL-13Rα1/Mac-1-dependent pathway may offer novel targets for therapeutic intervention in the future. PMID:26160172

  8. Method of securing filter elements

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Erik P.; Haslam, Jeffery L.; Mitchell, Mark A.

    2016-10-04

    A filter securing system including a filter unit body housing; at least one tubular filter element positioned in the filter unit body housing, the tubular filter element having a closed top and an open bottom; a dimple in either the filter unit body housing or the top of the tubular filter element; and a socket in either the filter unit body housing or the top of the tubular filter element that receives the dimple in either the filter unit body housing or the top of the tubular filter element to secure the tubular filter element to the filter unit body housing.

  9. Edge Preserved Speckle Noise Reduction Using Integrated Fuzzy Filters.

    Science.gov (United States)

    Biradar, Nagashettappa; Dewal, M L; Rohit, Manoj Kumar

    2014-01-01

    Echocardiographic images are inherent with speckle noise which makes visual reading and analysis quite difficult. The multiplicative speckle noise masks finer details, necessary for diagnosis of abnormalities. A novel speckle reduction technique based on integration of geometric, wiener, and fuzzy filters is proposed and analyzed in this paper. The denoising applications of fuzzy filters are studied and analyzed along with 26 denoising techniques. It is observed that geometric filter retains noise and, to address this issue, wiener filter is embedded into the geometric filter during iteration process. The performance of geometric-wiener filter is further enhanced using fuzzy filters and the proposed despeckling techniques are called integrated fuzzy filters. Fuzzy filters based on moving average and median value are employed in the integrated fuzzy filters. The performances of integrated fuzzy filters are tested on echocardiographic images and synthetic images in terms of image quality metrics. It is observed that the performance parameters are highest in case of integrated fuzzy filters in comparison to fuzzy and geometric-fuzzy filters. The clinical validation reveals that the output images obtained using geometric-wiener, integrated fuzzy, nonlocal means, and details preserving anisotropic diffusion filters are acceptable. The necessary finer details are retained in the denoised echocardiographic images.

  10. Bioreactors addressing diabetes mellitus.

    Science.gov (United States)

    Minteer, Danielle M; Gerlach, Jorg C; Marra, Kacey G

    2014-11-01

    The concept of bioreactors in biochemical engineering is a well-established process; however, the idea of applying bioreactor technology to biomedical and tissue engineering issues is relatively novel and has been rapidly accepted as a culture model. Tissue engineers have developed and adapted various types of bioreactors in which to culture many different cell types and therapies addressing several diseases, including diabetes mellitus types 1 and 2. With a rising world of bioreactor development and an ever increasing diagnosis rate of diabetes, this review aims to highlight bioreactor history and emerging bioreactor technologies used for diabetes-related cell culture and therapies.

  11. Geometric calibration of lens and filter distortions for multispectral filter-wheel cameras.

    Science.gov (United States)

    Brauers, Johannes; Aach, Til

    2011-02-01

    High-fidelity color image acquisition with a multispectral camera utilizes optical filters to separate the visible electromagnetic spectrum into several passbands. This is often realized with a computer-controlled filter wheel, where each position is equipped with an optical bandpass filter. For each filter wheel position, a grayscale image is acquired and the passbands are finally combined to a multispectral image. However, the different optical properties and non-coplanar alignment of the filters cause image aberrations since the optical path is slightly different for each filter wheel position. As in a normal camera system, the lens causes additional wavelength-dependent image distortions called chromatic aberrations. When transforming the multispectral image with these aberrations into an RGB image, color fringes appear, and the image exhibits a pincushion or barrel distortion. In this paper, we address both the distortions caused by the lens and by the filters. Based on a physical model of the bandpass filters, we show that the aberrations caused by the filters can be modeled by displaced image planes. The lens distortions are modeled by an extended pinhole camera model, which results in a remaining mean calibration error of only 0.07 pixels. Using an absolute calibration target, we then geometrically calibrate each passband and compensate for both lens and filter distortions simultaneously. We show that both types of aberrations can be compensated and present detailed results on the remaining calibration errors.

  12. A Self-Learning MAC Protocol for Energy Harvesting and Spectrum Access in Cognitive Radio Sensor Networks

    Directory of Open Access Journals (Sweden)

    Mohammed Hawa

    2016-01-01

    Full Text Available The fusion of Wireless Sensor Networks (WSNs and Cognitive Radio Networks (CRNs into Cognitive Radio Sensor Networks (CRSNs is quite an attractive proposal, because it allows a distributed set of low-powered sensor nodes to opportunistically access spectrum bands that are underutilized by their licensed owners (called primary users (PUs. In addition, when the PUs are actively transmitting in their own bands, sensor nodes can switch to energy harvesting mode to obtain their energy needs (for free, to achieve almost perpetual life. In this work, we present a novel and fully distributed MAC protocol, called S-LEARN, that allows sensor nodes in a CRSN to entwine their RF energy harvesting and data transmission activities, while intelligently addressing the issue of disproportionate difference between the high power necessary for the node to transmit data packets and the small amount of power it can harvest wirelessly from the environment. The presented MAC protocol can improve both the network throughput and total harvested energy, while being robust to changes in the network configuration. Moreover, S-LEARN can keep the cost of the system low, and it avoids the pitfalls from which centralized systems suffer.

  13. History-based MAC Protocol for Low Duty-Cycle Wireless Sensor Networks: the SLACK-MAC Protocol

    Directory of Open Access Journals (Sweden)

    Affoua Thérèse Aby

    2016-06-01

    Full Text Available Wireless sensor networks (WSNs are increasingly used in environmental monitoring applications. They are designed to operate for several months by featuring low activity cycles in order to save energy. In this paper, we propose a Medium Access Control (MAC protocol for suchWSNs with very low duty-cycles of 1% and less. Nodes are activated randomly and use a history of previous successful frame exchanges to decide their next activation time. We study the choice of the history size, and we compare the performance of our protocol with other protocols from the literature. We show by simulations and real experiments that with a limited history size of only six entries, our protocol achieves better performance than other protocols from the literature, while keeping the advantages of fully asynchronous protocols.

  14. A VHDL Implementation of Direct, Pipelined and Distributed Arithmetic FIR Filters

    Directory of Open Access Journals (Sweden)

    Sucharitha. L

    2013-03-01

    Full Text Available Digital filters are typically used to modify or alter the attributes of a signal in the time or frequency domain. In this project, various FIR filter structures will be studied and implemented in VHDL. Basic arithmetic blocks to carry out DSP on FPGAs will be discussed. The very popular LUT based approach for arithmetic circuit implementation will be presented. The conventional PDSP MAC and Distributed arithmetic MAC units will be implemented and their performance will be compared. Usage of Pipelining in multipliers for improving the speed will also be discussed. The ModelSim XE simulator will be used to simulate the design at various stages. Xilinx synthesis tool (XST will be used to synthesize the design for spartan3E family FPGA (XC3S500E. Xilinx Placement {&} Routing tools will be used for backend, design optimization and I/O routing

  15. Generalized Hampel Filters

    Science.gov (United States)

    Pearson, Ronald K.; Neuvo, Yrjö; Astola, Jaakko; Gabbouj, Moncef

    2016-12-01

    The standard median filter based on a symmetric moving window has only one tuning parameter: the window width. Despite this limitation, this filter has proven extremely useful and has motivated a number of extensions: weighted median filters, recursive median filters, and various cascade structures. The Hampel filter is a member of the class of decsion filters that replaces the central value in the data window with the median if it lies far enough from the median to be deemed an outlier. This filter depends on both the window width and an additional tuning parameter t, reducing to the median filter when t=0, so it may be regarded as another median filter extension. This paper adopts this view, defining and exploring the class of generalized Hampel filters obtained by applying the median filter extensions listed above: weighted Hampel filters, recursive Hampel filters, and their cascades. An important concept introduced here is that of an implosion sequence, a signal for which generalized Hampel filter performance is independent of the threshold parameter t. These sequences are important because the added flexibility of the generalized Hampel filters offers no practical advantage for implosion sequences. Partial characterization results are presented for these sequences, as are useful relationships between root sequences for generalized Hampel filters and their median-based counterparts. To illustrate the performance of this filter class, two examples are considered: one is simulation-based, providing a basis for quantitative evaluation of signal recovery performance as a function of t, while the other is a sequence of monthly Italian industrial production index values that exhibits glaring outliers.

  16. Environmental Assessment for Construction of Security Forces Facility/Demolition of Existing Building 528 MacDill AFB, Florida

    Science.gov (United States)

    2005-08-01

    Gennarro and Tish Maddy MacDill Air Force Base Environmental Restoration Program 7621 Hillsborough Loop Dr. MacDill AFB, FL 33621-5207 Bryan...MacDill Air Force Base Maddy, Tish Lead-based Paint and Asbestos Records, Building 528. Verbal correspondence, February 1, 2005. Naval

  17. 42 CFR 405.1140 - MAC review of ALJ decision in a case remanded by a Federal district court.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 2 2010-10-01 2010-10-01 false MAC review of ALJ decision in a case remanded by a...) Medicare Appeals Council Review § 405.1140 MAC review of ALJ decision in a case remanded by a Federal... district court for further consideration and the MAC remands the case to an ALJ, a decision subsequently...

  18. 42 CFR 405.1062 - Applicability of local coverage determinations and other policies not binding on the ALJ and MAC.

    Science.gov (United States)

    2010-10-01

    ... other policies not binding on the ALJ and MAC. 405.1062 Section 405.1062 Public Health CENTERS FOR... of local coverage determinations and other policies not binding on the ALJ and MAC. (a) ALJs and the MAC are not bound by LCDs, LMRPs, or CMS program guidance, such as program memoranda and manual...

  19. Wideband Lithium Niobate FBAR Filters

    Directory of Open Access Journals (Sweden)

    Thomas Baron

    2013-01-01

    Full Text Available Filters based on film bulk acoustic resonators (FBARs are widely used for mobile phone applications, but they can also address wideband aerospace requirements. These devices need high electromechanical coupling coefficients to achieve large band pass filters. The piezoelectric material LiNbO3 complies with such specifications and is compatible with standard fabrication processes. In this work, simple metal—LiNbO3—metal structures have been developed to fabricate single FBAR elements directly connected to each other on a single chip. A fabrication process based on LiNbO3/silicon Au-Au bonding and LiNbO3 lapping/polishing has been developed and is proposed in this paper. Electrical measurements of these FBAR filters are proposed and commented exhibiting filters with 8% of fractional bandwidth and 3.3 dB of insertion losses. Electrical measurements show possibilities to obtain 14% of fractional bandwidth. These devices have been packaged, allowing for power handling, thermal, and ferroelectric tests, corresponding to spatial conditions.

  20. Multibeam Advisory Committee (MAC) - Three Years of Working Towards the Consistent Acquisition of High Quality Multibeam Echosounder Data Across the US Academic Fleet

    Science.gov (United States)

    Johnson, P. D.; Beaudoin, J. D.; Ferrini, V. L.

    2014-12-01

    In 2010 the National Science Foundation (NSF) held a meeting to address the variability in quality of multibeam echosounder (MBES) data for ships of the US Academic Fleet. The participants of this meeting identified that there was a strong need to coordinate operational efforts for multibeam data acquisition across all vessels of the fleet. To address this need, the University of New Hampshire's Center for Coastal and Ocean Mapping joined with Lamont-Doherty Earth Observatory in submitting a proposal to NSF to form the Multibeam Advisory Committee (MAC), which was funded in the fall of 2011. The MAC through the last three years has assembled a team of experts who have been called upon to respond to questions about MBES data acquisition and data quality, conduct shipboard assessments of MBES systems, create documentation supporting best practices for multibeam acquisition and data workflow, and to develop tools to support both data acquisition and quality assessment. Tools and techniques developed through the MAC include: SVP Editor - a graphical display and editing program for SVP, CTD, XBT, and XSV data. This program integrates directly with multibeam acquisition software to both receive navigation and depth information, used during the processing of the sound velocity data, and also has the ability to send edited and processed cast directly to the sounder. MBES Accuracy and Swath Performance Tools - tools which can assess both the accuracy of MBES bathymetric data as compared to a reference surface grid and to examine swath width performance of MBES systems as a function of depth. Remote Patch Test Support - the MAC provides patch test site selection, detailed execution plans, and tools to support the transmittal of a downsized raw MBES data files from ships over satellite in order to determine the angular offset values (pitch, heading, and roll) for MBES systems with no MAC personnel on board. Built In Self Test (BIST) Evaluation Tools - tools which can plot and

  1. The Impact of Dynamic RTS Threshold Adjustment for IEEE 802.11 MAC Protocol

    Directory of Open Access Journals (Sweden)

    Mostafa Mjidi

    2009-01-01

    Full Text Available In recent years, wireless technologies and application received great attention. The Medium Access Control (MAC protocol is the main element that determines the efficiency in sharing the limited communication bandwidth of the wireless channel in wireless local area networks (WLANs. IEEE 802.11 introduced the optional RTS/CTS handshaking mechanism to address the hidden terminal problem as well as to reduces the chance of collision in case of higher node density and traffic. RTS Threshold (RT determines when RTS/CTS mechanism should be used and proved to be an important parameter for performance characteristics in data transmission. We first investigate to find a meaningful threshold value according to the network situation and determine the impact of using or disengaging the RTS/CTS optional mechanism and dynamically adjust the RTS Threshold to maximize data transmission. The results show a significant improvement over existing CSMA/CA and RTS/CTS schemes. Our adaptive scheme performed even better when data rate increases. We verify our proposed scheme both analytically and with extensive network simulation using ns-2.

  2. Ceramic High Efficiency Particulate Air (HEPA) Filter Final Report CRADA No. TC02160.0

    Energy Technology Data Exchange (ETDEWEB)

    Mitchell, M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Bergman, W. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2017-08-25

    The technical objective of this project was to develop a ceramic HEPA filter technology, by initially producing and testing coupon ceramics, small scale prototypes, and full scale prototype HEPA filters, and to address relevant manufacturing and commercialization technical issues.

  3. AN INTEGRATED APPROACH AGAINST APP-DDoS FOR MITIGATING IP SPOOFED ATTACKS AND MAC ATTACKS

    Directory of Open Access Journals (Sweden)

    S.PRABHA

    2013-06-01

    Full Text Available The nature of data traffic flow from wired network is extremely different from wireless network. Therefore as the DDoS application service attacks from the wired ones are produced from IP frame and wireless ones from Media Access Control (MAC frame. The variant in the frames motivates the requirement of enhanced resistive mechanism for application DDoS attacks for interfaced internet application servers enabled with both wired and wireless infrastructure. With the wired and wireless interface access in internet application services made us to present an Application Service Network Request Identification (ASNRI scheme in this work. ASNRI scheme first identifies the type of data stream frame and input it to the IHBCM method. In Bayes packet classifier, separated data frames are verified for its malicious characteristic in its data frame attributes to filter out the malicious data packet frames. Simulations are carried out to evaluate the performance of ASNRI to conventional application DDoS attack resistance schemes by measuring its true positive and true negative of data frame classification and its malicious attack resistance rate at different traffic volumes.In the process of applying Bayes has been planned to provide insight into the behavior of this technique itself. In this paper has been illustrated the sensitivity of the algorithm to its initial assumptions and demonstrated the use of two techniques, one to break the Gaussian assumptions and the other to improve the quality of discriminators as input, It leads to significant improvements in the accuracy of the Bayes technique. Integrated Hidden Markov Model (HMM and Bayes Packet Classifier based Gaussian distribution factor to detect and respond to the App-DDoS attacks if they occur during a flash crowd event for both dynamic and stationary objects.

  4. 基于用户过滤的校园无线网用户聚类方法%User filtering based campus WLAN user clustering method

    Institute of Scientific and Technical Information of China (English)

    仇一泓; 尧婷娟; 秦丰林; 葛连升

    2014-01-01

    With the widespread of smart terminals such as smart phones and smart pads, using MAC address as user iden-tification in campus wireless local area network (WLAN) user clustering research cannot exactly represent user behavior. An user filtering based user clustering is proposed. This method filters users’ behavior data by their degree of activeness, and then further conducts clustering analysis of campus WLAN user behavior. The experimental result verifies the effec-tiveness of the proposed method.%随着智能终端地普及,在校园无线网用户聚类研究中采用MAC地址作为用户区分已不能真实反映用户的行为,为此,提出了一个基于用户过滤的校园无线网用户聚类方法,该方法基于用户活跃度对用户行为数据进行过滤,在此基础上对校园无线网用户行为做进一步地聚类分析。实验结果表明了该方法的有效性。

  5. MST Filterability Tests

    Energy Technology Data Exchange (ETDEWEB)

    Poirier, M. R. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Burket, P. R. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Duignan, M. R. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2015-03-12

    The Savannah River Site (SRS) is currently treating radioactive liquid waste with the Actinide Removal Process (ARP) and the Modular Caustic Side Solvent Extraction Unit (MCU). The low filter flux through the ARP has limited the rate at which radioactive liquid waste can be treated. Recent filter flux has averaged approximately 5 gallons per minute (gpm). Salt Batch 6 has had a lower processing rate and required frequent filter cleaning. Savannah River Remediation (SRR) has a desire to understand the causes of the low filter flux and to increase ARP/MCU throughput. In addition, at the time the testing started, SRR was assessing the impact of replacing the 0.1 micron filter with a 0.5 micron filter. This report describes testing of MST filterability to investigate the impact of filter pore size and MST particle size on filter flux and testing of filter enhancers to attempt to increase filter flux. The authors constructed a laboratory-scale crossflow filter apparatus with two crossflow filters operating in parallel. One filter was a 0.1 micron Mott sintered SS filter and the other was a 0.5 micron Mott sintered SS filter. The authors also constructed a dead-end filtration apparatus to conduct screening tests with potential filter aids and body feeds, referred to as filter enhancers. The original baseline for ARP was 5.6 M sodium salt solution with a free hydroxide concentration of approximately 1.7 M.3 ARP has been operating with a sodium concentration of approximately 6.4 M and a free hydroxide concentration of approximately 2.5 M. SRNL conducted tests varying the concentration of sodium and free hydroxide to determine whether those changes had a significant effect on filter flux. The feed slurries for the MST filterability tests were composed of simple salts (NaOH, NaNO2, and NaNO3) and MST (0.2 – 4.8 g/L). The feed slurry for the filter enhancer tests contained simulated salt batch 6 supernate, MST, and filter enhancers.

  6. A Priority-Based Adaptive MAC Protocol for Wireless Body Area Networks

    Directory of Open Access Journals (Sweden)

    Sabin Bhandari

    2016-03-01

    Full Text Available In wireless body area networks (WBANs, various sensors and actuators are placed on/inside the human body and connected wirelessly. WBANs have specific requirements for healthcare and medical applications, hence, standard protocols like the IEEE 802.15.4 cannot fulfill all the requirements. Consequently, many medium access control (MAC protocols, mostly derived from the IEEE 802.15.4 superframe structure, have been studied. Nevertheless, they do not support a differentiated quality of service (QoS for the various forms of traffic coexisting in a WBAN. In particular, a QoS-aware MAC protocol is essential for WBANs operating in the unlicensed Industrial, Scientific, and Medical (ISM bands, because different wireless services like Bluetooth, WiFi, and Zigbee may coexist there and cause severe interference. In this paper, we propose a priority-based adaptive MAC (PA-MAC protocol for WBANs in unlicensed bands, which allocates time slots dynamically, based on the traffic priority. Further, multiple channels are effectively utilized to reduce access delays in a WBAN, in the presence of coexisting systems. Our performance evaluation results show that the proposed PA-MAC outperforms the IEEE 802.15.4 MAC and the conventional priority-based MAC in terms of the average transmission time, throughput, energy consumption, and data collision ratio.

  7. A Priority-Based Adaptive MAC Protocol for Wireless Body Area Networks.

    Science.gov (United States)

    Bhandari, Sabin; Moh, Sangman

    2016-03-18

    In wireless body area networks (WBANs), various sensors and actuators are placed on/inside the human body and connected wirelessly. WBANs have specific requirements for healthcare and medical applications, hence, standard protocols like the IEEE 802.15.4 cannot fulfill all the requirements. Consequently, many medium access control (MAC) protocols, mostly derived from the IEEE 802.15.4 superframe structure, have been studied. Nevertheless, they do not support a differentiated quality of service (QoS) for the various forms of traffic coexisting in a WBAN. In particular, a QoS-aware MAC protocol is essential for WBANs operating in the unlicensed Industrial, Scientific, and Medical (ISM) bands, because different wireless services like Bluetooth, WiFi, and Zigbee may coexist there and cause severe interference. In this paper, we propose a priority-based adaptive MAC (PA-MAC) protocol for WBANs in unlicensed bands, which allocates time slots dynamically, based on the traffic priority. Further, multiple channels are effectively utilized to reduce access delays in a WBAN, in the presence of coexisting systems. Our performance evaluation results show that the proposed PA-MAC outperforms the IEEE 802.15.4 MAC and the conventional priority-based MAC in terms of the average transmission time, throughput, energy consumption, and data collision ratio.

  8. A tale of two mitochondrial channels, MAC and PTP, in apoptosis.

    Science.gov (United States)

    Kinnally, Kathleen W; Antonsson, Bruno

    2007-05-01

    The crucial step in the intrinsic, or mitochondrial, apoptotic pathway is permeabilization of the mitochondrial outer membrane. Permeabilization triggers release of apoptogenic factors, such as cytochrome c, from the mitochondrial intermembrane space into the cytosol where these factors ensure propagation of the apoptotic cascade and execution of cell death. However, the mechanism(s) underlying permeabilization of the outer membrane remain controversial. Two mechanisms, involving opening of two different mitochondrial channels, have been proposed to be responsible for the permeabilization; the permeability transition pore (PTP) in the inner membrane and the mitochondrial apoptosis-induced channel (MAC) in the outer membrane. Opening of PTP would lead to matrix swelling, subsequent rupture of the outer membrane, and an unspecific release of intermembrane proteins into the cytosol. However, many believe PTP opening is a consequence of apoptosis and this channel is thought to principally play a role in necrosis, not apoptosis. Activation of MAC is exquisitely regulated by Bcl-2 family proteins, which are the sentinels of apoptosis. MAC provides specific pores in the outer membrane for the passage of intermembrane proteins, in particular cytochrome c, to the cytosol. The electrophysiological characteristics of MAC are very similar to Bax channels and depletion of Bax significantly diminishes MAC activity, suggesting that Bax is an essential constituent of MAC in some systems. The characteristics of various mitochondrial channels and Bax are compared. The involvement of MAC and PTP activities in apoptosis of disease and their pharmacology are discussed.

  9. A cross-layer duty cycle MAC protocol supporting a pipeline feature for wireless sensor networks.

    Science.gov (United States)

    Tong, Fei; Xie, Rong; Shu, Lei; Kim, Young-Chon

    2011-01-01

    Although the conventional duty cycle MAC protocols for Wireless Sensor Networks (WSNs) such as RMAC perform well in terms of saving energy and reducing end-to-end delivery latency, they were designed independently and require an extra routing protocol in the network layer to provide path information for the MAC layer. In this paper, we propose a new cross-layer duty cycle MAC protocol with data forwarding supporting a pipeline feature (P-MAC) for WSNs. P-MAC first divides the whole network into many grades around the sink. Each node identifies its grade according to its logical hop distance to the sink and simultaneously establishes a sleep/wakeup schedule using the grade information. Those nodes in the same grade keep the same schedule, which is staggered with the schedule of the nodes in the adjacent grade. Then a variation of the RTS/CTS handshake mechanism is used to forward data continuously in a pipeline fashion from the higher grade to the lower grade nodes and finally to the sink. No extra routing overhead is needed, thus increasing the network scalability while maintaining the superiority of duty-cycling. The simulation results in OPNET show that P-MAC has better performance than S-MAC and RMAC in terms of packet delivery latency and energy efficiency.

  10. DLD-MAC:A Diffserv-based Low-delay MAC Protocol for WSNs%DLD-MAC:一种区分服务的低时延传感器网络MAC协议

    Institute of Scientific and Technical Information of China (English)

    舒俊浩; 白光伟; 沈航

    2012-01-01

    针对现有无线传感器网络MAC协议不能提供区分服务和传输时廷较大的问题,在经典多跳传输协议DW-MAC的基础上,提出了一种具有区分服务功能的低时延MAC协议—DLD-MAC(Diffserv-based Low-Delay MAC).其基本思路是让高优先级数据选择更小的竞争窗口,以降低时延和能耗.Markov建模分析表明,DLD-MAC能对不同优先级的业务流进行很好的服务区分,而且相较于传统的无线传感器网络MAC协议,其在时延性能上有显著优势,能更有效地保障服务质量.%Considering that most of the existing MAC protocols in wireless sensor networks do not support any priority scheme,this paper proposed a novel,Diffserv-based low-delay MAC mechanismCDLD-MAC),on the basis of the existing DW-MAC protocol. The main idea is that, by introducing differentiated services, the high priority data chooses smaller back-off window, so that it can achieve much more chance to be delivered, and its packet transmission latency and energy consumption can be reduced significantly compared with low priority data. On the other hand, a Markov chain model was designed in this work, to analyze and evaluate the mechanism performance. Our analytical analyses show that the proposed DLD-MAC can effectively make the high priority data achieve higher QoS over the low priority data, and achieve much lower transmission latency than traditional MAC protocol as well,which is adequate to serve delay-sensitive data flow.

  11. An extended smart utilization medium access control (ESU-MAC) protocol for ad hoc wireless systems

    Science.gov (United States)

    Vashishtha, Jyoti; Sinha, Aakash

    2006-05-01

    The demand for spontaneous setup of a wireless communication system has increased in recent years for areas like battlefield, disaster relief operations etc., where a pre-deployment of network infrastructure is difficult or unavailable. A mobile ad-hoc network (MANET) is a promising solution, but poses a lot of challenges for all the design layers, specifically medium access control (MAC) layer. Recent existing works have used the concepts of multi-channel and power control in designing MAC layer protocols. SU-MAC developed by the same authors, efficiently uses the 'available' data and control bandwidth to send control information and results in increased throughput via decreasing contention on the control channel. However, SU-MAC protocol was limited for static ad-hoc network and also faced the busy-receiver node problem. We present the Extended SU-MAC (ESU-MAC) protocol which works mobile nodes. Also, we significantly improve the scheme of control information exchange in ESU-MAC to overcome the busy-receiver node problem and thus, further avoid the blockage of control channel for longer periods of time. A power control scheme is used as before to reduce interference and to effectively re-use the available bandwidth. Simulation results show that ESU-MAC protocol is promising for mobile, ad-hoc network in terms of reduced contention at the control channel and improved throughput because of channel re-use. Results show a considerable increase in throughput compared to SU-MAC which could be attributed to increased accessibility of control channel and improved utilization of data channels due to superior control information exchange scheme.

  12. An Economic Analysis of MAC Versus WALANT: A Trigger Finger Release Surgery Case Study.

    Science.gov (United States)

    Codding, Jason L; Bhat, Suneel B; Ilyas, Asif M

    2017-07-01

    There has been recent interest in wide awake hand surgery, also referred to as "wide awake local anesthesia with no tourniquet" (WALANT) surgery. Using a model of single trigger finger release (TFR) surgery, a hypothesis was made that WALANT would result in decreased hospital time and cost than patients receiving sedation with monitored anesthetic care (MAC). Consecutive cases of single TFR surgery with MAC were compared with WALANT. All surgeries were performed in the same manner, at the same facility, and by the same surgeon. Total operating room (OR) time, surgical time, recovery time, and anesthesia costs were analyzed. There were 78 patients: 31 MAC and 47 WALANT. The MAC group averaged 27.2 minutes of OR time; the WALANT group averaged 25.2 minutes. The MAC group surgical time was 10.2 minutes versus WALANT of 10.4 minutes. Post-operatively, the MAC group averaged 72.3 minutes in the recovery room compared with WALANT group of 30.2 minutes. Each case performed under MAC had a minimum of excess charges from anesthesia of approximately $105. Patients undergoing single TFR surgery under WALANT trended toward less time in the OR, had similar surgical times, and spent significantly less time in the recovery room, compared with MAC, thereby resulting in less indirect costs. Each MAC case also had minimum direct excess anesthesia charges of $105, which knowingly underestimates overall charges as it excludes material and fixed costs associated with the delivery of anesthesia. Avoiding sedation for high-volume procedures such as TFR may result in significant systemic savings to payers, and in the future with bundling and episode-based payments can become increasingly important to patients, facilities, and surgeons.

  13. PLEIOTROPHIN, A MULTIFUNCTIONAL CYTOKINE AND GROWTH FACTOR, INDUCES LEUKOCYTE RESPONSES THROUGH THE INTEGRIN MAC-1.

    Science.gov (United States)

    Shen, Di; Podolnikova, Nataly P; Yakubenko, Valentin P; Ardell, Christopher L; Balabiyev, Arnat; Ugarova, Tatiana P; Wang, Xu

    2017-09-22

    Pleiotrophin (PTN) is a multifunctional, cationic, glycosaminoglycan-binding cytokine and growth factor involved in numerous physiological and pathological processes, including tissue repair and inflammation-related diseases. PTN has been shown to promote leukocyte responses by inducing their migration and expression of inflammatory cytokines. However, the mechanisms through which PTN mediates these responses remain unclear. Here, we identified the integrin Mac-1 (αMβ2, CD11b/CD18) as the receptor mediating macrophage adhesion and migration to PTN. We also found that expression of Mac-1 on the surface of human embryonic kidney (HEK) 293 cells induced their adhesion and migration to PTN. Accordingly, PTN promoted Mac-1-dependent cell spreading and initiated intracellular signaling manifested in phosphorylation of Erk1/2. While binding to PTN, Mac-1 on Mac-1-expressing HEK293 cells appear to cooperate with cell-surface proteoglycans, since both anti-Mac-1 function-blocking mAb and heparin were required to block adhesion. Moreover, biolayer interferometry and NMR indicated a direct interaction between the αMI domain, the major ligand-binding region of Mac-1, and PTN. Using peptide libraries, we found that in PTN, the αMI domain bound sequences enriched in basic and hydrophobic residues, indicating that PTN conforms to the general principle of ligand-recognition specificity of the αMI domain toward cationic proteins/peptides. Finally, using recombinant PTN-derived fragments, we show that PTN contains two distinct Mac-1-binding sites in each of its constitutive domains. Collectively, these results identify PTN as a ligand for the integrin Mac-1 on the surface of leukocytes and suggest that this interaction may play a role in inflammatory responses. Copyright © 2017, The American Society for Biochemistry and Molecular Biology.

  14. Guided image filtering.

    Science.gov (United States)

    He, Kaiming; Sun, Jian; Tang, Xiaoou

    2013-06-01

    In this paper, we propose a novel explicit image filter called guided filter. Derived from a local linear model, the guided filter computes the filtering output by considering the content of a guidance image, which can be the input image itself or another different image. The guided filter can be used as an edge-preserving smoothing operator like the popular bilateral filter [1], but it has better behaviors near edges. The guided filter is also a more generic concept beyond smoothing: It can transfer the structures of the guidance image to the filtering output, enabling new filtering applications like dehazing and guided feathering. Moreover, the guided filter naturally has a fast and nonapproximate linear time algorithm, regardless of the kernel size and the intensity range. Currently, it is one of the fastest edge-preserving filters. Experiments show that the guided filter is both effective and efficient in a great variety of computer vision and computer graphics applications, including edge-aware smoothing, detail enhancement, HDR compression, image matting/feathering, dehazing, joint upsampling, etc.

  15. Particle Filter Tracking without Dynamics

    Directory of Open Access Journals (Sweden)

    Jaime Ortegon-Aguilar

    2007-01-01

    Full Text Available People tracking is an interesting topic in computer vision. It has applications in industrial areas such as surveillance or human-machine interaction. Particle Filters is a common algorithm for people tracking; challenging situations occur when the target's motion is poorly modelled or with unexpected motions. In this paper, an alternative to address people tracking is presented. The proposed algorithm is based in particle filters, but instead of using a dynamical model, it uses background subtraction to predict future locations of particles. The algorithm is able to track people in omnidirectional sequences with a low frame rate (one or two frames per second. Our approach can tackle unexpected discontinuities and changes in the direction of the motion. The main goal of the paper is to track people from laboratories, but it has applications in surveillance, mainly in controlled environments.

  16. Measurements of the Sunyaev-Zel'dovich Effect in MACS J0647.7+7015 and MACS J1206.2-0847 at High Angular Resolution with MUSTANG

    CERN Document Server

    Young, Alexander H; Romero, Charles; Sayers, Jack; Balestra, Italo; Clarke, Tracy E; Czakon, Nicole; Devlin, Mark; Dicker, Simon R; Ferrari, Chiara; Girardi, Marisa; Golwala, Sunil; Intema, Huib; Korngut, Phillip M; Mason, Brian S; Mercurio, Amata; Nonino, Mario; Reese, Erik D; Rosati, Piero; Sarazin, Craig; Umetsu, Keiichi

    2014-01-01

    We present high resolution (9$^{\\prime \\prime}$) imaging of the Sunyaev-Zel'dovich Effect (SZE) toward two massive galaxy clusters, MACS J0647.7+7015 ($z=0.591$) and MACS J1206.2-0847 ($z=0.439$). We compare these 90 GHz measurements, taken with the MUSTANG receiver on the Green Bank Telescope, with generalized Navarro-Frenk-White (gNFW) models derived from Bolocam 140 GHz SZE data as well as maps of the thermal gas derived from {\\it Chandra} X-ray observations. For MACS J0647.7+7015, we find a gNFW profile with core slope parameter $\\gamma= 0.9$ fits the MUSTANG image with $\\chi^{2}_{red}=1.005$ and probability to exceed (PTE) = 0.34. For MACS J1206.2-0847, we find $\\gamma=0.7$, $\\chi^{2}_{red}=0.993$, and PTE = 0.70. In addition, we find a significant ($>$3-$\\sigma$) residual SZE feature in MACS J1206.2-0847 coincident with a group of galaxies identified in VLT data and filamentary structure found in a weak-lensing mass reconstruction. We suggest the detected sub-structure may be the SZE decrement from a lo...

  17. A Study on the Distributed Antenna Based Heterogeneous Cognitive Wireless Network Synchronous MAC Protocol

    Directory of Open Access Journals (Sweden)

    Lian-Fen Huang

    2015-01-01

    Full Text Available This paper introduces distributed antennas into a cognitive radio network and presents a heterogeneous network. The best contribution of this paper is that it designs a synchronous cognitive MAC protocol (DAHCWNS-MAC protocol: distributed antenna based heterogeneous cognitive wireless network synchronous MAC protocol. The novel protocol aims at combining the advantages of cognitive radio and distributed antennas to fully utilize the licensed spectrum, broaden the communication range, and improve throughput. This paper carries out the mathematical modeling and performance simulation to demonstrate its superiority in improving the network throughput at the cost of increasing antenna hardware costs.

  18. Approximate discrete time analysis of the hybrid Token-CDMA MAC system

    CSIR Research Space (South Africa)

    Liu, YS

    2007-09-01

    Full Text Available of the Hybrid Token-CDMA MAC System Yi Sheng Liu, Student Member, IEEE, Fambirai Takawira, Member, IEEE , and Hong Jun Xu, Member, IEEE Abstract— In this paper a hybrid Token-CDMA based medium access control (MAC) protocol is considered. The MAC scheme...Zulu-Natal, Howard College Campus. He received the BSc degree in 1984 from the University of Guilin Technology and the MSc degree from the Institute of Telecontrol and Telemeasure in Shi Jian Zhuang, 1989, and the PhD degree from the Beijing University...

  19. Learn AppleScript The Comprehensive Guide to Scripting and Automation on MAC OS X

    CERN Document Server

    Rosenthal, Hanaan

    2009-01-01

    AppleScript is an English-like, easy-to-understand scripting language built into every Mac. AppleScript can automate hundreds of AppleScriptable applications, performing tasks both large and small, complex and simple. Learn AppleScript: The Comprehensive Guide to Scripting and Automation on Mac OS X, Third Edition has been completely updated for Mac OS X Snow Leopard. It's all here, with an emphasis on practical information that will help you solve any automation problem-from the most mundane repetitive tasks to highly integrated workflows of complex systems. * Friendly enough for beginners, d

  20. Computer Aided Filter Design.

    Science.gov (United States)

    1987-12-01

    FIR filter can be described in the following. [Ref. 2] 1. FIR filters with exact linear phase can be easily designed. Linear phase filters are important...response for the four cases of linear phase filter , i.e., even or odd symmetry with an even or odd number of terms, can be written in the form: H (eJ ) = e...Ansari, The Design and Application of Optimal FIR Fractional Phase Filters , IEEE on Acoutics, Speech and Signal Processing, Vol. 2, 1987, pp.896-899. 77 14

  1. A unified Kalman filter

    Science.gov (United States)

    Stubberud, Allen R.

    2017-01-01

    When considering problems of linear sequential estimation, two versions of the Kalman filter, the continuous-time version and the discrete-time version, are often used. (A hybrid filter also exists.) In many applications in which the Kalman filter is used, the system to which the filter is applied is a linear continuous-time system, but the Kalman filter is implemented on a digital computer, a discrete-time device. The two general approaches for developing a discrete-time filter for implementation on a digital computer are: (1) approximate the continuous-time system by a discrete-time system (called discretization of the continuous-time system) and develop a filter for the discrete-time approximation; and (2) develop a continuous-time filter for the system and then discretize the continuous-time filter. Generally, the two discrete-time filters will be different, that is, it can be said that discretization and filter generation are not, in general, commutative operations. As a result, any relationship between the discrete-time and continuous-time versions of the filter for the same continuous-time system is often obfuscated. This is particularly true when an attempt is made to generate the continuous-time version of the Kalman filter through a simple limiting process (the sample period going to zero) applied to the discrete-time version. The correct result is, generally, not obtained. In a 1961 research report, Kalman showed that the continuous-time Kalman filter can be obtained from the discrete-time Kalman filter by taking limits as the sample period goes to zero if the white noise process for the continuous-time version is appropriately defined. Using this basic concept, a discrete-time Kalman filter can be developed for a continuous-time system as follows: (1) discretize the continuous-time system using Kalman's technique; and (2) develop a discrete-time Kalman filter for that discrete-time system. Kalman's results show that the discrete-time filter generated in

  2. Bias aware Kalman filters

    DEFF Research Database (Denmark)

    Drecourt, J.-P.; Madsen, H.; Rosbjerg, Dan

    2006-01-01

    . The colored noise filter formulation is extended to correct both time correlated and uncorrelated model error components. A more stable version of the separate filter without feedback is presented. The filters are implemented in an ensemble framework using Latin hypercube sampling. The techniques...... are illustrated on a simple one-dimensional groundwater problem. The results show that the presented filters outperform the standard Kalman filter and that the implementations with bias feedback work in more general conditions than the implementations without feedback. 2005 Elsevier Ltd. All rights reserved....

  3. Optimal Source-Based Filtering of Malicious Traffic

    CERN Document Server

    Soldo, Fabio; Markopoulou, Athina

    2010-01-01

    In this paper, we consider the problem of blocking malicious traffic on the Internet, via source-based filtering. In particular, we consider filtering via access control lists (ACLs): these are already available at the routers today but are a scarce resource because they are stored in the expensive ternary content addressable memory (TCAM). Aggregation (by filtering source prefixes instead of individual IP addresses) helps reduce the number of filters, but comes also at the cost of blocking legitimate traffic originating from the filtered prefixes. We show how to optimally choose which source prefixes to filter, for a variety of realistic attack scenarios and operators' policies. In each scenario, we design optimal, yet computationally efficient, algorithms. Using logs from Dshield.org, we evaluate the algorithms and demonstrate that they bring significant benefit in practice.

  4. MAC Protocol for Ad Hoc Networks Using a Genetic Algorithm

    Directory of Open Access Journals (Sweden)

    Omar Elizarraras

    2014-01-01

    Full Text Available The problem of obtaining the transmission rate in an ad hoc network consists in adjusting the power of each node to ensure the signal to interference ratio (SIR and the energy required to transmit from one node to another is obtained at the same time. Therefore, an optimal transmission rate for each node in a medium access control (MAC protocol based on CSMA-CDMA (carrier sense multiple access-code division multiple access for ad hoc networks can be obtained using evolutionary optimization. This work proposes a genetic algorithm for the transmission rate election considering a perfect power control, and our proposition achieves improvement of 10% compared with the scheme that handles the handshaking phase to adjust the transmission rate. Furthermore, this paper proposes a genetic algorithm that solves the problem of power combining, interference, data rate, and energy ensuring the signal to interference ratio in an ad hoc network. The result of the proposed genetic algorithm has a better performance (15% compared to the CSMA-CDMA protocol without optimizing. Therefore, we show by simulation the effectiveness of the proposed protocol in terms of the throughput.

  5. Pliable Cognitive MAC for Heterogeneous Adaptive Cognitive Radio Sensor Networks.

    Directory of Open Access Journals (Sweden)

    Mohammed Al-Medhwahi

    Full Text Available The rapid expansion of wireless monitoring and surveillance applications in several domains reinforces the trend of exploiting emerging technologies such as the cognitive radio. However, these technologies have to adjust their working concepts to consider the common characteristics of conventional wireless sensor networks (WSNs. The cognitive radio sensor network (CRSN, still an immature technology, has to deal with new networks that might have different types of data, traffic patterns, or quality of service (QoS requirements. In this paper, we design and model a new cognitive radio-based medium access control (MAC algorithm dealing with the heterogeneous nature of the developed networks in terms of either the traffic pattern or the required QoS for the node applications. The proposed algorithm decreases the consumed power on several fronts, provides satisfactory levels of latency and spectrum utilization with efficient scheduling, and manages the radio resources for various traffic conditions. An intensive performance evaluation is conducted to study the impact of key parameters such as the channel idle time length, node density, and the number of available channels. The performance evaluation of the proposed algorithm shows a better performance than the comparable protocols. Moreover, the results manifest that the proposed algorithm is suitable for real time monitoring applications.

  6. MAC to VAX Connectivity: Heartrate Spectral Analysis System

    Science.gov (United States)

    Rahman, Hasan H.; Faruque, Monazer

    1993-01-01

    The heart rate Spectral Analysis System (SAS) acquires and analyzes, in real-time, the Space Shuttle onboard electrocardiograph (EKG) experiment signals, calculates the heartrate, and applies a Fast Fourier Transformation (FFT) to the heart rate. The system also calculates other statistical parameters such as the 'mean heart rate' over specific time period and heart rate histogram. This SAS is used by NASA Principal Investigators as a research tool to determine the effects of weightlessness on the human cardiovascular system. This is also used to determine if Lower Body Negative Pressure (LBNP) is an effective countermeasure to the orthostatic intolerance experienced by astronauts upon return to normal gravity. In microgravity, astronauts perform the LBNP experiment in the mid deck of the Space Shuttle. The experiment data are downlinked by the orbiter telemetry system, then processed and analyzed in real-time by the integrated Life Sciences Data Acquisition (LSDS) - Spectral Analysis System. The data system is integrated within the framework of two different computer systems, VAX and Macintosh (Mac), using the networking infrastructure to assist the investigators in further understanding the most complex machine on Earth--the human body.

  7. Tracing the merger history of MACS clusters using the GMRT

    CERN Document Server

    Paul, S; Intema, H T

    2014-01-01

    Galaxy-cluster merger shocks efficiently accelerate the ambient electrons through diffusive shock acceleration and amplify magnetic field by compressing the Inter Cluster Medium. As a result, such objects produce a significant amount of synchrotron radio emission. Radio halo and Mpc scale peripheral radio relics thus help us to trace back the cluster formation history. To study the dynamical state of the galaxy clusters and their relation to the merging scenario, as a pilot project, we thus observed four suitable candidates from the MACS (Massive Cluster Survey) cluster sample. Observations were carried out simultaneously at 610 and 235 MHz with the GMRT. We observed a rare phenomena in the cluster MACSJ0014.3-3022, which hosts both a peripheral spectacular radio relic and an unusually flat spectrum central giant radio halo of more than 1.5 Mpc dimension. We also report that another cluster MACSJ0152.5-2852 is possibly showing the sign of one of the earliest and young merging system where, we saw a faint 0.5 ...

  8. A MAC Protocol to Support Monitoring of Underwater Spaces †

    Science.gov (United States)

    Santos, Rodrigo; Orozco, Javier; Ochoa, Sergio F.; Meseguer, Roc; Eggly, Gabriel; Pistonesi, Marcelo F.

    2016-01-01

    Underwater sensor networks are becoming an important field of research, because of their everyday increasing application scope. Examples of their application areas are environmental and pollution monitoring (mainly oil spills), oceanographic data collection, support for submarine geolocalization, ocean sampling and early tsunamis alert. The challenge of performing underwater communications is well known, provided that radio signals are useless in this medium, and a wired solution is too expensive. Therefore, the sensors in these networks transmit their information using acoustic signals that propagate well under water. This data transmission type not only brings an opportunity, but also several challenges to the implementation of these networks, e.g., in terms of energy consumption, data transmission and signal interference. In order to help advance the knowledge in the design and implementation of these networks for monitoring underwater spaces, this paper proposes a MAC protocol for acoustic communications between the nodes, based on a self-organized time division multiple access mechanism. The proposal was evaluated using simulations of a real monitoring scenario, and the obtained results are highly encouraging. PMID:27355950

  9. A MAC Protocol to Support Monitoring of Underwater Spaces

    Directory of Open Access Journals (Sweden)

    Rodrigo Santos

    2016-06-01

    Full Text Available Underwater sensor networks are becoming an important field of research, because of their everyday increasing application scope. Examples of their application areas are environmental and pollution monitoring (mainly oil spills, oceanographic data collection, support for submarine geolocalization, ocean sampling and early tsunamis alert. The challenge of performing underwater communications is well known, provided that radio signals are useless in this medium, and a wired solution is too expensive. Therefore, the sensors in these networks transmit their information using acoustic signals that propagate well under water. This data transmission type not only brings an opportunity, but also several challenges to the implementation of these networks, e.g., in terms of energy consumption, data transmission and signal interference. In order to help advance the knowledge in the design and implementation of these networks for monitoring underwater spaces, this paper proposes a MAC protocol for acoustic communications between the nodes, based on a self-organized time division multiple access mechanism. The proposal was evaluated using simulations of a real monitoring scenario, and the obtained results are highly encouraging.

  10. A MAC Protocol to Support Monitoring of Underwater Spaces.

    Science.gov (United States)

    Santos, Rodrigo; Orozco, Javier; Ochoa, Sergio F; Meseguer, Roc; Eggly, Gabriel; Pistonesi, Marcelo F

    2016-01-01

    Underwater sensor networks are becoming an important field of research, because of their everyday increasing application scope. Examples of their application areas are environmental and pollution monitoring (mainly oil spills), oceanographic data collection, support for submarine geolocalization, ocean sampling and early tsunamis alert. The challenge of performing underwater communications is well known, provided that radio signals are useless in this medium, and a wired solution is too expensive. Therefore, the sensors in these networks transmit their information using acoustic signals that propagate well under water. This data transmission type not only brings an opportunity, but also several challenges to the implementation of these networks, e.g., in terms of energy consumption, data transmission and signal interference. In order to help advance the knowledge in the design and implementation of these networks for monitoring underwater spaces, this paper proposes a MAC protocol for acoustic communications between the nodes, based on a self-organized time division multiple access mechanism. The proposal was evaluated using simulations of a real monitoring scenario, and the obtained results are highly encouraging.

  11. Emergency Handling for MAC Protocol in Human Body Communication

    Directory of Open Access Journals (Sweden)

    Kwon Youngmi

    2011-01-01

    Full Text Available The human body communication (HBC is a technology that enables short range data communication using the human body as a medium, like an electrical wire. Thus it removes the need for a traditional antenna. HBC may be used as a type of data communication in body area network (BAN, while the devices are being in contact with body. One of important issues in BAN is an emergency alarm because it may be closely related to human life. For emergency data communication, the most critical factor is the time constraint. IEEE 802.15.6 specifies that the emergency alarm for the BAN must be notified in less than 1 sec and must provide prioritization mechanisms for emergency traffic and notification. As one type of BAN, the HBC must follow this recommendation, too. Existing emergency handling methods in BAN are based on the carrier sensing capability on radio frequencies to detect the status of channels. However, PHY protocol in HBC does not provide the carrier sensing. So the previous methods are not well suitable for HBC directly. Additionally, in the environment that the emergency rate is very low, the allocation of dedicated slot(s for emergency in each superframe is very wasteful. In this work, we proposed specific emergency handling operation for human body communication's medium access control (HBC-MAC protocol to meet the emergency requirements for BAN. We also showed the optimal number of emergency slots for the various combinations of beacon intervals and emergency rates.

  12. LAMAN: Load Adaptable MAC for Ad Hoc Networks

    Directory of Open Access Journals (Sweden)

    Realp Marc

    2005-01-01

    Full Text Available In mobile ad hoc radio networks, mechanisms on how to access the radio channel are extremely important in order to improve network efficiency. In this paper, the load adaptable medium access control for ad hoc networks (LAMAN protocol is described. LAMAN is a novel decentralized multipacket MAC protocol designed following a cross-layer approach. Basically, this protocol is a hybrid CDMA-TDMA-based protocol that aims at throughput maximization in multipacket communication environments by efficiently combining contention and conflict-free protocol components. Such combination of components is used to adapt the nodes' access priority to changes on the traffic load while, at the same time, accounting for the multipacket reception (MPR capability of the receivers. A theoretical analysis of the system is developed presenting closed expressions of network throughput and packet delay. By simulations the validity of our analysis is shown and the performances of a LAMAN-based system and an Aloha-CDMA-based one are compared.

  13. Design and Analysis of an Asynchronous Zero Collision MAC Protocol

    CERN Document Server

    Lee, Jiwoong

    2008-01-01

    This paper proposes and analyzes a distributed MAC protocol that achieves zero collision with no control message exchange nor synchronization. ZC (ZeroCollision) is neither reservation-based nor dynamic TDMA; the protocol supports variable-length packets and does not lose efficiency when some of the stations do not transmit. At the same time, ZC is not a CSMA; in its steady state, it is completely collision-free. The stations transmit repeatedly in a round-robin order once the convergence state is reached. If some stations skip their turn, their transmissions are replaced by idle $20 \\mu$-second mini-slots that enable the other stations to keep track of their order. Because of its short medium access delay and its efficiency, the protocol supports both real-time and elastic applications. The protocol allows for nodes leaving and joining the network; it can allocate more throughput to specific nodes (such as an access point). The protocol is robust against carrier sensing errors or clock drift. While collision...

  14. Pliable Cognitive MAC for Heterogeneous Adaptive Cognitive Radio Sensor Networks.

    Science.gov (United States)

    Al-Medhwahi, Mohammed; Hashim, Fazirulhisyam; Ali, Borhanuddin Mohd; Sali, Aduwati

    2016-01-01

    The rapid expansion of wireless monitoring and surveillance applications in several domains reinforces the trend of exploiting emerging technologies such as the cognitive radio. However, these technologies have to adjust their working concepts to consider the common characteristics of conventional wireless sensor networks (WSNs). The cognitive radio sensor network (CRSN), still an immature technology, has to deal with new networks that might have different types of data, traffic patterns, or quality of service (QoS) requirements. In this paper, we design and model a new cognitive radio-based medium access control (MAC) algorithm dealing with the heterogeneous nature of the developed networks in terms of either the traffic pattern or the required QoS for the node applications. The proposed algorithm decreases the consumed power on several fronts, provides satisfactory levels of latency and spectrum utilization with efficient scheduling, and manages the radio resources for various traffic conditions. An intensive performance evaluation is conducted to study the impact of key parameters such as the channel idle time length, node density, and the number of available channels. The performance evaluation of the proposed algorithm shows a better performance than the comparable protocols. Moreover, the results manifest that the proposed algorithm is suitable for real time monitoring applications.

  15. Modified pterional craniotomy without "MacCarty keyhole".

    Science.gov (United States)

    Moscovici, Samuel; Mizrahi, Cezar José; Margolin, Emil; Spektor, Sergey

    2016-02-01

    Pterional craniotomy is one of the most widely used approaches in neurosurgery. The MacCarty keyhole has remained the preferred means of beginning the craniotomy to achieve a low access point; however, the bone opening may result in a residual defect and an aesthetically unpleasant depression in the periorbital area. We present our modification of the traditional technique. Instead of drilling the keyhole in the frontoperiorbital area, the classical location, we perform a 5 × 15 mm strip craniectomy at the lowest accessible point in the infratemporal fossa, corresponding to the projection of the most lateral point of the sphenoid ridge. The anterior half of this opening exposes the basal frontal dura, while the posterior half brings the temporal dura into view. This modified technique was applied in 48 pterional craniotomies performed for removal of a variety of neoplasms during 2014-2015. There were no approach-related complications. Aesthetic outcomes and patient acceptance have been good; no patient developed skin depression in the periorbital area. In our experience, craniotomy for a pterional approach with the lowest possible access to the frontotemporal skull base may be performed by drilling a narrow oblong opening, without the use of any keyhole or burr hole, to create a smaller skull defect and achieve optimal aesthetic outcomes. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. Ceramic fiber filter technology

    Energy Technology Data Exchange (ETDEWEB)

    Holmes, B.L.; Janney, M.A.

    1996-06-01

    Fibrous filters have been used for centuries to protect individuals from dust, disease, smoke, and other gases or particulates. In the 1970s and 1980s ceramic filters were developed for filtration of hot exhaust gases from diesel engines. Tubular, or candle, filters have been made to remove particles from gases in pressurized fluidized-bed combustion and gasification-combined-cycle power plants. Very efficient filtration is necessary in power plants to protect the turbine blades. The limited lifespan of ceramic candle filters has been a major obstacle in their development. The present work is focused on forming fibrous ceramic filters using a papermaking technique. These filters are highly porous and therefore very lightweight. The papermaking process consists of filtering a slurry of ceramic fibers through a steel screen to form paper. Papermaking and the selection of materials will be discussed, as well as preliminary results describing the geometry of papers and relative strengths.

  17. Addressing psychiatric comorbidity.

    Science.gov (United States)

    Woody, G E; McLellan, A T; O'Brien, C P; Luborsky, L

    1991-01-01

    Research studies indicate that addressing psychiatric comorbidity can improve treatment for selected groups of substance-abusing patients. However, the chances for implementing the necessary techniques on a large scale are compromised by the absence of professional input and guidance within programs. This is especially true in public programs, which treat some of the most disadvantaged, disturbed, and socially destructive individuals in the entire mental health system. One starting point for upgrading the level of knowledge and training of staff members who work in this large treatment system could be to develop a better and more authoritative information dissemination network. Such a system exists in medicine; physicians are expected to read appropriate journals and to guide their treatment decisions using the data contained in the journals. Standards of practice and methods for modifying current practice are within the tradition of reading new facts, studying old ones, and comparing treatment outcome under different conditions with what is actually being done. No such general system of information-gathering or -sharing exists, particularly in public treatment programs. One of the most flagrant examples of this "educational shortfall" can be found among those methadone programs that adamantly insist on prescribing no more than 30 to 35 mg/day for all patients, in spite of the overwhelming evidence that these dose levels generally are inadequate. In some cases, program directors are unaware of studies that have shown the relationship between dose and outcome. In other cases, they are aware of the studies but do not modify their practices accordingly. This example of inadequate dosing is offered as an example of one situation that could be improved by adherence to a system of authoritative and systematic information dissemination. Many issues in substance abuse treatment do not lend themselves to information dissemination as readily as that of methadone dosing

  18. Analysis of an Adaptive P-Persistent MAC Scheme for WLAN Providing Delay Fairness

    Science.gov (United States)

    Yen, Chih-Ming; Chang, Chung-Ju; Chen, Yih-Shen; Huang, Ching Yao

    The paper proposes and analyzes an adaptive p-persistent-based (APP) medium access control (MAC) scheme for IEEE 802.11 WLAN. The APP MAC scheme intends to support delay fairness for every station in each access, denoting small delay variance. It differentiates permission probabilities of transmission for stations which are incurred with various packet delays. This permission probability is designed as a function of the numbers of retransmissions and re-backoffs so that stations with larger packet delay are endowed with higher permission probability. Also, the scheme is analyzed by a Markov-chain analysis, where the collision probability, the system throughput, and the average delay are successfully obtained. Numerical results show that the proposed APP MAC scheme can attain lower mean delay and higher mean throughput. In the mean time, simulation results are given to justify the validity of the analysis, and also show that the APP MAC scheme can achieve more delay fairness than conventional algorithms.

  19. Corrections to "Connectivity-Based Reliable Multicast MAC Protocol for IEEE 802.11 Wireless LANs"

    Directory of Open Access Journals (Sweden)

    Choi Woo-Yong

    2010-01-01

    Full Text Available We have found the errors in the throughput formulae presented in our paper "Connectivity-based reliable multicast MAC protocol for IEEE 802.11 wireless LANs". We provide the corrected formulae and numerical results.

  20. Evaluation of video transmission of MAC protocols in wireless sensor network

    Science.gov (United States)

    Maulidin, Mahmuddin, M.; Kamaruddin, L. M.; Elsaikh, Mohamed

    2016-08-01

    Wireless Sensor Network (WSN) is a wireless network which consists of sensor nodes scattered in a particular area which are used to monitor physical or environment condition. Each node in WSN is also scattered in sensor field, so an appropriate scheme of MAC protocol should have to develop communication link for data transferring. Video transmission is one of the important applications for the future that can be transmitted with low aspect in side of cost and also power consumption. In this paper, comparison of five different MAC WSN protocol for video transmission namely IEEE 802.11 standard, IEEE 802.15.4 standard, CSMA/CA, Berkeley-MAC, and Lightweight-MAC protocol are studied. Simulation experiment has been conducted in OMNeT++ with INET network simulator software to evaluate the performance. Obtained results indicate that IEEE 802.11 works better than other protocol in term of packet delivery, throughput, and latency.

  1. Four new species of Adicella MacLachlan (Trichoptera: Leptoceridae: Triaenodini) from Sabah, East Malaysia

    NARCIS (Netherlands)

    Huisman, J.; Andersen, T.

    1997-01-01

    Four new species of Adicella MacLachlan, 1877, A. anakpanah spec, nov., A. bavanga spec, nov., A. danumensis spec, nov., and A. gada spec, nov., from Sabah (Borneo), East Malaysia, are described and figured.

  2. An Improved MAC Scheme of HORNET Based on Node Structure with Variable Optical Buffer

    Institute of Scientific and Technical Information of China (English)

    Nian Fang; Lutang Wang; Zhaoming Huang

    2003-01-01

    An improved unslotted CSMA/CA MAC scheme of HORNET based on the node structure with variable optical buffer is reported. It can be used for transmitting high effectively all variable IP packets in the WDM network.

  3. Industrial WSN Based on IR-UWB and a Low-Latency MAC Protocol

    Science.gov (United States)

    Reinhold, Rafael; Underberg, Lisa; Wulf, Armin; Kays, Ruediger

    2016-07-01

    Wireless sensor networks for industrial communication require high reliability and low latency. As current wireless sensor networks do not entirely meet these requirements, novel system approaches need to be developed. Since ultra wideband communication systems seem to be a promising approach, this paper evaluates the performance of the IEEE 802.15.4 impulse-radio ultra-wideband physical layer and the IEEE 802.15.4 Low Latency Deterministic Network (LLDN) MAC for industrial applications. Novel approaches and system adaptions are proposed to meet the application requirements. In this regard, a synchronization approach based on circular average magnitude difference functions (CAMDF) and on a clean template (CT) is presented for the correlation receiver. An adapted MAC protocol titled aggregated low latency (ALL) MAC is proposed to significantly reduce the resulting latency. Based on the system proposals, a hardware prototype has been developed, which proves the feasibility of the system and visualizes the real-time performance of the MAC protocol.

  4. Side channel analysis of some hash based MACs:A response to SHA-3 requirements

    DEFF Research Database (Denmark)

    function which is more resistant to known side channel attacks (SCA) when plugged into HMAC, or that has an alternative MAC mode which is more resistant to known SCA than the other submitted alternatives. In response to this, we perform differential power analysis (DPA) on the possible smart card...... implementations of some of the recently proposed MAC alternatives to NMAC (a fully analyzed variant of HMAC) and HMAC algorithms and NMAC/HMAC versions of some recently proposed hash and compression function modes. We show that the recently proposed BNMAC and KMDP MAC schemes are even weaker than NMAC....../HMAC against the DPA attacks, whereas multi-lane NMAC, EMD MAC and the keyed wide-pipe hash have similar security to NMAC against the DPA attacks. Our DPA attacks do not work on the NMAC setting of MDC-2, Grindahl and MAME compression functions. This talk outlines our results....

  5. A Multi-Channel Diversity Based MAC Protocol for Power-Constrained Cognitive Ad Hoc Networks

    CERN Document Server

    Wang, Yichen; Du, Qinghe; Zhang, Chao

    2011-01-01

    One of the major challenges in the medium access control (MAC) protocol design over cognitive Ad Hoc networks (CAHNs) is how to efficiently utilize multiple opportunistic channels, which vary dynamically and are subject to limited power resources. To overcome this challenge, in this paper we first propose a novel diversity technology called \\emph{Multi-Channel Diversity} (MCD), allowing each secondary node to use multiple channels simultaneously with only one radio per node under the upperbounded power. Using the proposed MCD, we develop a MCD based MAC (MCD-MAC) protocol, which can efficiently utilize available channel resources through joint power-channel allocation. Particularly, we convert the joint power-channel allocation to the Multiple-Choice Knapsack Problem, such that we can obtain the optimal transmission strategy to maximize the network throughput through dynamic programming. Simulation results show that our proposed MCD-MAC protocol can significantly increase the network throughput as compared to...

  6. 78 FR 2879 - Federal Agricultural Mortgage Corporation Funding and Fiscal Affairs; Farmer Mac Investment...

    Science.gov (United States)

    2013-01-15

    ..., 2012 (77 FR 66375) is effective December 31, 2012. FOR FURTHER INFORMATION CONTACT: Joseph T. Connor... 3052-AC56 Federal Agricultural Mortgage Corporation Funding and Fiscal Affairs; Farmer Mac...

  7. AN EFFICIENT MAC PROTOCOL BASED ON HYBRID SUPERFRAME FOR WIRELESS SENSOR NETWORKS

    Directory of Open Access Journals (Sweden)

    Ge Ma

    2009-07-01

    Full Text Available Designing low energy consumption, high efficiency Media Access Control (MAC protocols are one ofthe most important directions in wireless sensor networks (WSN. In this paper, we proposed a newcontention reserve MAC protocol, named CRMAC, under the inspiration of IEEE 802.15.4’s superframestructure. CRMAC is a MAC protocol suitable for intra-cluster WSN that combines the advantages ofcontention and schedule-based MAC protocols. We introduce the mechanism and superframe structure ofCRMAC in detail and verified the performance of this protocol through simulations. Our results showthat CRMAC performs better than IEEE 802.15.4 in energy consumption, system delay and networkthroughput. CRMAC is especially suitable for short packet transmission under low load networks, whichis the main situation in WSN.

  8. Experimental Evaluation of Simulation Abstractions for Wireless Sensor Network MAC Protocols

    Directory of Open Access Journals (Sweden)

    G. P. Halkes

    2010-01-01

    Full Text Available The evaluation of MAC protocols for Wireless Sensor Networks (WSNs is often performed through simulation. These simulations necessarily abstract away from reality in many ways. However, the impact of these abstractions on the results of the simulations has received only limited attention. Moreover, many studies on the accuracy of simulation have studied either the physical layer and per link effects or routing protocol effects. To the best of our knowledge, no other work has focused on the study of the simulation abstractions with respect to MAC protocol performance. In this paper, we present the results of an experimental study of two often used abstractions in the simulation of WSN MAC protocols. We show that a simple SNR-based reception model can provide quite accurate results for metrics commonly used to evaluate MAC protocols. Furthermore, we provide an analysis of what the main sources of deviation are and thereby how the simulations can be improved to provide even better results.

  9. Three-zone pupil filters

    Science.gov (United States)

    Sheppard, Colin J. R.; Campos, Juan; Escalera, Juan C.; Ledesma, Silvia

    2008-07-01

    The performance of pupil filters consisting of three zones each of constant complex amplitude transmittance is investigated. For filters where the transmittance is real, different classes of potentially useful filter are identified. These include leaky filters with an inner zone of low amplitude transmittance, pure phase filters with phase change of π, and equal area filters.

  10. Mac-2 binding protein is a novel E-selectin ligand expressed by breast cancer cells.

    Science.gov (United States)

    Shirure, Venktesh S; Reynolds, Nathan M; Burdick, Monica M

    2012-01-01

    Hematogenous metastasis involves the adhesion of circulating tumor cells to vascular endothelium of the secondary site. We hypothesized that breast cancer cell adhesion is mediated by interaction of endothelial E-selectin with its glycoprotein counter-receptor(s) expressed on breast cancer cells. At a hematogenous wall shear rate, ZR-75-1 breast cancer cells specifically adhered to E-selectin expressing human umbilical vein endothelial cells when tested in parallel plate flow chamber adhesion assays. Consistent with their E-selectin ligand activity, ZR-75-1 cells expressed flow cytometrically detectable epitopes of HECA-452 mAb, which recognizes high efficiency E-selectin ligands typified by sialofucosylated moieties. Multiple E-selectin reactive proteins expressed by ZR-75-1 cells were revealed by immunoprecipitation with E-selectin chimera (E-Ig chimera) followed by Western blotting. Mass spectrometry analysis of the 72 kDa protein, which exhibited the most prominent E-selectin ligand activity, corresponded to Mac-2 binding protein (Mac-2BP), a heretofore unidentified E-selectin ligand. Immunoprecipitated Mac-2BP expressed sialofucosylated epitopes and possessed E-selectin ligand activity when tested by Western blot analysis using HECA-452 mAb and E-Ig chimera, respectively, demonstrating that Mac-2BP is a novel high efficiency E-selectin ligand. Furthermore, silencing the expression of Mac-2BP from ZR-75-1 cells by shRNA markedly reduced their adhesion to E-selectin expressing cells under physiological flow conditions, confirming the functional E-selectin ligand activity of Mac-2BP on intact cells. In addition to ZR-75-1 cells, several other E-selectin ligand positive breast cancer cell lines expressed Mac-2BP as detected by Western blot and flow cytometry, suggesting that Mac-2BP may be an E-selectin ligand in a variety of breast cancer types. Further, invasive breast carcinoma tissue showed co-localized expression of Mac-2BP and HECA-452 antigens by

  11. Truman and MacArthur: The Winding Road to Dismissal

    Science.gov (United States)

    2006-01-01

    Fort Leavenworth,KS,66027 8. PERFORMING ORGANIZATION REPORT NUMBER 9. SPONSORING/ MONITORING AGENCY NAME(S) AND ADDRESS(ES) 10. SPONSOR/MONITOR’S...once told Dean Acheson, his secretary of state, he liked “being a nose buster and an ass kicker much better” than a statesman.) On the other hand

  12. Efficiency analysis of color image filtering

    Directory of Open Access Journals (Sweden)

    Egiazarian Karen

    2011-01-01

    Full Text Available Abstract This article addresses under which conditions filtering can visibly improve the image quality. The key points are the following. First, we analyze filtering efficiency for 25 test images, from the color image database TID2008. This database allows assessing filter efficiency for images corrupted by different noise types for several levels of noise variance. Second, the limit of filtering efficiency is determined for independent and identically distributed (i.i.d. additive noise and compared to the output mean square error of state-of-the-art filters. Third, component-wise and vector denoising is studied, where the latter approach is demonstrated to be more efficient. Fourth, using of modern visual quality metrics, we determine that for which levels of i.i.d. and spatially correlated noise the noise in original images or residual noise and distortions because of filtering in output images are practically invisible. We also demonstrate that it is possible to roughly estimate whether or not the visual quality can clearly be improved by filtering.

  13. Topics in particle filtering and smoothing

    NARCIS (Netherlands)

    Saha, Saikat

    2009-01-01

    Particle filtering/smoothing is a relatively new promising class of algorithms to deal with the estimation problems in nonlinear and/or non- Gaussian systems. Currently, this is a very active area of research and there are many issues that are not either properly addressed or are still open. One of

  14. Achievable rates for transmission of discrete constellations over the Gaussian MAC channe

    CERN Document Server

    Ghaffar, Rizwan; Lee, Jungwon

    2011-01-01

    In this paper we consider the achievable rate region of the Gaussian Multiple Access Channel (MAC) when suboptimal transmission schemes are employed. Focusing on the two-user MAC and assuming uncoded Pulse Amplitude Modulation (PAM), we derive a rate region that is a pentagon, and propose a strategy with which it can be achieved. We also compare the region with outer bounds and with orthogonal transmission.

  15. Performance evaluation of MAC transmission power control in wireless sensor networks.

    OpenAIRE

    Egea López, Estebán

    2007-01-01

    In this paper we provide a method to analytically compute the energy saving provided by the use of Transmission Power Control (TPC) at the MAC layer in Wireless Sensor Networks (WSN). We consider a classical TPC mechanism: data packets are transmitted with the minimum required power to achieve a given packet error probability, whereas the additional MAC control packets are transmitted with the nominal (maximum) power. This scheme has been chosen because it does not modify the network to...

  16. John MacCulloch, MD (1773-1835): a dedicated geologist.

    Science.gov (United States)

    Hull, Gillian

    2007-11-01

    The teaching in Scottish medical schools in the second half of the 18th century had a reputation that stretched far beyond Britain. Edinburgh attracted students not only for its high academic standards but also for its freedom from religious constraints and its developing interest in the sciences. John MacCulloch was taught at Edinburgh by Joseph Black (1728-99) who had chosen chemistry as a career rather than medicine. Already MacCulloch's enquiring mind ranged over many subjects.

  17. TraPy-MAC: Traffic Priority Aware Medium Access Control Protocol for Wireless Body Area Network.

    Science.gov (United States)

    Ullah, Fasee; Abdullah, Abdul Hanan; Kaiwartya, Omprakash; Cao, Yue

    2017-06-01

    Recently, Wireless Body Area Network (WBAN) has witnessed significant attentions in research and product development due to the growing number of sensor-based applications in healthcare domain. Design of efficient and effective Medium Access Control (MAC) protocol is one of the fundamental research themes in WBAN. Static on-demand slot allocation to patient data is the main approach adopted in the design of MAC protocol in literature, without considering the type of patient data specifically the level of severity on patient data. This leads to the degradation of the performance of MAC protocols considering effectiveness and traffic adjustability in realistic medical environments. In this context, this paper proposes a Traffic Priority-Aware MAC (TraPy-MAC) protocol for WBAN. It classifies patient data into emergency and non-emergency categories based on the severity of patient data. The threshold value aided classification considers a number of parameters including type of sensor, body placement location, and data transmission time for allocating dedicated slots patient data. Emergency data are not required to carry out contention and slots are allocated by giving the due importance to threshold value of vital sign data. The contention for slots is made efficient in case of non-emergency data considering threshold value in slot allocation. Moreover, the slot allocation to emergency and non-emergency data are performed parallel resulting in performance gain in channel assignment. Two algorithms namely, Detection of Severity on Vital Sign data (DSVS), and ETS Slots allocation based on the Severity on Vital Sign (ETS-SVS) are developed for calculating threshold value and resolving the conflicts of channel assignment, respectively. Simulations are performed in ns2 and results are compared with the state-of-the-art MAC techniques. Analysis of results attests the benefit of TraPy-MAC in comparison with the state-of-the-art MAC in channel assignment in realistic medical

  18. Autonomous Navigation System Using a Fuzzy Adaptive Nonlinear H∞ Filter

    Directory of Open Access Journals (Sweden)

    Fariz Outamazirt

    2014-09-01

    Full Text Available Although nonlinear H∞ (NH∞ filters offer good performance without requiring assumptions concerning the characteristics of process and/or measurement noises, they still require additional tuning parameters that remain fixed and that need to be determined through trial and error. To address issues associated with NH∞ filters, a new SINS/GPS sensor fusion scheme known as the Fuzzy Adaptive Nonlinear H∞ (FANH∞ filter is proposed for the Unmanned Aerial Vehicle (UAV localization problem. Based on a real-time Fuzzy Inference System (FIS, the FANH∞ filter continually adjusts the higher order of the Taylor development thorough adaptive bounds  and adaptive disturbance attenuation , which significantly increases the UAV localization performance. The results obtained using the FANH∞ navigation filter are compared to the NH∞ navigation filter results and are validated using a 3D UAV flight scenario. The comparison proves the efficiency and robustness of the UAV localization process using the FANH∞ filter.

  19. Characterization of a Regenerable Impactor Filter for Spacecraft Cabin Applications

    Science.gov (United States)

    Agui, Juan H.; Vijayakumar, R.

    2015-01-01

    Regenerable filters will play an important role in human exploration beyond low-Earth orbit. Life Support Systems aboard crewed spacecrafts will have to operate reliably and with little maintenance over periods of more than a year, even multiple years. Air filters are a key component of spacecraft life support systems, but they often require frequent routine maintenance. Bacterial filters aboard the International Space Station require almost weekly cleaning of the pre-filter screen to remove large lint debris captured in the microgravity environment. The source of the airborne matter which is collected on the filter screen is typically from clothing fibers, biological matter (hair, skin, nails, etc.) and material wear. Clearly a need for low maintenance filters requiring little to no crew intervention will be vital to the success of the mission. An impactor filter is being developed and tested to address this need. This filter captures large particle matter through inertial separation and impaction methods on collection surfaces, which can be automatically cleaned after they become heavily loaded. The impactor filter can serve as a pre-filter to augment the life of higher efficiency filters that capture fine and ultrafine particles. A prototype of the filter is being tested at the Particulate Filtration Laboratory at NASA Glenn Research Center to determine performance characteristics, including particle cut size and overall efficiency. Model results are presented for the flow characteristics near the orifice plate through which the particle-laden flow is accelerated as well as around the collection bands.

  20. FPGA IMPLEMENTATION OF MAC HEADER BLOCK OF TRANSMITTER FOR Wi-Fi

    Directory of Open Access Journals (Sweden)

    A.M.BHAVIKATTI,

    2011-04-01

    Full Text Available For the wireless communication, IEEE 802.11 is one of the protocols available. The IEEE 802.11b uses the medium access control layer (MAC for wireless local area network. These wireless local area networks use Carrier Sense multiple access with collision avoidance (CSMA/CS for the MAC layer .But only the MAC layer for transmitter is considered here for simulation. So, the Wi-Fi transmitter module is divided into 5 blocks i.e. Data Unit Interface block, Controller block, Pay Load Data Storage, MAC Header Register block and Data Processing block. In this paper we consider only the simulation of MAC header register blocks. So, other blocks i.e. Data unit interface block, Controller block, pay load Data Storage block & Data Processing block are not discussed further in this paper. A field programmable gate array (FPGA device has been used as the hardware implementation platform. The proposed MAC-layer hardware is implemented with Xilinx xcv300e Virtex E FPGA.

  1. FPGA IMPLEMENTATION OF MAC HEADER BLOCK OF TRANSMITTER FOR Wi-Fi

    Directory of Open Access Journals (Sweden)

    A.M.BHAVIKATTI,

    2011-04-01

    Full Text Available For the wireless communication, IEEE 802.11 is one of the protocols available. The IEEE 802.11b uses the medium access control layer (MAC for wireless local area network. These wireless local area networks use Carrier Sense multiple access with collision avoidance (CSMA/CS for the MAC layer .But only the MAC layer for transmitter is considered here for simulation. So, the Wi-Fi transmitter module is divided into 5 blocks i.e. Data Unit Interface block, Controller block, Pay Load Data Storage, MAC Header Register block and Data Processing block. In this paper we consider only the simulation of MAC header register blocks. So, other blocks i.e. Data unit interface block, Controller block, pay load Data Storage block & Data Processing block are not discussed further in this paper. A field programmable gate array (FPGA device has been used as the hardware implementation platform. The proposed MAC-layer hardware is implemented with Xilinx xcv300e Virtex E FPGA

  2. HARVESTED ENERGY-ADAPTIVE MAC PROTOCOL FOR ENERGY HARVESTING IOT NETWORKS

    Directory of Open Access Journals (Sweden)

    Hyeong-Kyu Lee

    2015-12-01

    Full Text Available In energy harvesting IoT networks, an energy queue state of an IoT device will change dynamically and the number of IoT devices that transmit data to the IoT AP will vary in a frame. So we need a MAC protocol to adjust the frame length taking the amount of energy of IoT devices into consideration. Since the existing Framed slotted ALOHA (F-ALOHA Medium Access Control (MAC protocol utilizes the fixed frame size, the resource efficiency can be reduced. In this paper, we propose a Harvested Energy-adaptive Medium Access Control (HEMAC protocol where an IoT Access Point (AP allocates slots in accordance with the number of IoT devices that try to transmit data in a frame. The proposed HE-MAC protocol improves the resource efficiency of the F-ALOHA MAC protocol. We show that the resource efficiency of the HE-MAC protocol is superior to those of the F-ALOHA MAC protocol through simulations.

  3. Address Points, Addressing, Published in 2008, Taylor County.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Address Points dataset, was produced all or in part from Orthoimagery information as of 2008. It is described as 'Addressing'. Data by this publisher are often...

  4. Generic Kalman Filter Software

    Science.gov (United States)

    Lisano, Michael E., II; Crues, Edwin Z.

    2005-01-01

    The Generic Kalman Filter (GKF) software provides a standard basis for the development of application-specific Kalman-filter programs. Historically, Kalman filters have been implemented by customized programs that must be written, coded, and debugged anew for each unique application, then tested and tuned with simulated or actual measurement data. Total development times for typical Kalman-filter application programs have ranged from months to weeks. The GKF software can simplify the development process and reduce the development time by eliminating the need to re-create the fundamental implementation of the Kalman filter for each new application. The GKF software is written in the ANSI C programming language. It contains a generic Kalman-filter-development directory that, in turn, contains a code for a generic Kalman filter function; more specifically, it contains a generically designed and generically coded implementation of linear, linearized, and extended Kalman filtering algorithms, including algorithms for state- and covariance-update and -propagation functions. The mathematical theory that underlies the algorithms is well known and has been reported extensively in the open technical literature. Also contained in the directory are a header file that defines generic Kalman-filter data structures and prototype functions and template versions of application-specific subfunction and calling navigation/estimation routine code and headers. Once the user has provided a calling routine and the required application-specific subfunctions, the application-specific Kalman-filter software can be compiled and executed immediately. During execution, the generic Kalman-filter function is called from a higher-level navigation or estimation routine that preprocesses measurement data and post-processes output data. The generic Kalman-filter function uses the aforementioned data structures and five implementation- specific subfunctions, which have been developed by the user on

  5. FILDIG: a program to filter brain electrical signals in the frequency domain.

    Science.gov (United States)

    Guevara, M A; Ramos, J; Hernández-González, M; Corsi-Cabrera, M

    2005-11-01

    A software program to filter brain electrical signals in the frequency domain has been developed and is presently reported. Many other filters are commercially available; however, most of them are linked to data acquisition and/or analysis programs rendering them costly. Depending on the experimental field, the full programs are not always needed. To overcome the need to obtain narrow bands in EEG research and other biological signals in an easy, fast and cheap way, we developed a computer program (FILDIG) that renders an almost ideal in-phase filter in the frequency domain and can be used in all types of personal microcomputers (PC and Mac's) and with few resources. The system uses an interactive graphic display and, with a minimum interface, it is capable of filtering multiple channels and simultaneously obtaining electrical signals (EEG, EMG, EOG, etc.) without noise or specific frequency bands.

  6. Concentric Split Flow Filter

    Science.gov (United States)

    Stapleton, Thomas J. (Inventor)

    2015-01-01

    A concentric split flow filter may be configured to remove odor and/or bacteria from pumped air used to collect urine and fecal waste products. For instance, filter may be designed to effectively fill the volume that was previously considered wasted surrounding the transport tube of a waste management system. The concentric split flow filter may be configured to split the air flow, with substantially half of the air flow to be treated traveling through a first bed of filter media and substantially the other half of the air flow to be treated traveling through the second bed of filter media. This split flow design reduces the air velocity by 50%. In this way, the pressure drop of filter may be reduced by as much as a factor of 4 as compare to the conventional design.

  7. Crux vena cava filter.

    Science.gov (United States)

    Murphy, Erin H; Johnson, Eric D; Kopchok, George E; Fogarty, Thomas J; Arko, Frank R

    2009-09-01

    Inferior vena cava filters are widely accepted for pulmonary embolic prophylaxis in high-risk patients with contraindications to anticoagulation. While long-term complications have been associated with permanent filters, retrievable filters are now available and have resulted in the rapid expansion of this technology. Nonetheless, complications are still reported with optional filters. Furthermore, device tilting and thrombus load may prevent retrieval in up to 30% of patients, thereby eliminating the benefits of this technology. The Crux vena cava filter is a novel, self-centering, low-profile filter that is designed for ease of delivery, retrievability and improved efficacy while limiting fatigue-related device complications. This device has been proven safe and user-friendly in an ovine model and has recently been implanted in human subjects.

  8. CrowdFilter

    DEFF Research Database (Denmark)

    Mortensen, Michael Lind; Wallace, Byron C.; Kraska, Tim

    for complex multi-criteria search problems through crowdsourcing. The CrowdFilter system is capable of supporting both criteria-level labels and n-gram rationales, capturing the human decision making process behind each filtering choice. Using the data provided through CrowdFilter we also introduce a novel......Multi-criteria filtering of mixed open/closed-world data is a time-consuming task, requiring significant manual effort when latent open-world attributes are present. In this work we introduce a novel open-world filtering framework CrowdFilter, enabling automatic UI generation and label elicitation...... multi-criteria active learning method; capable of incorporating labels and n-gram rationales per inclusion criteria, and thus capable of determining both clear includes/excludes, as well as complex borderline cases. By incorporating the active learning approach into the elicitation process of Crowd...

  9. Conservative Noise Filters

    Directory of Open Access Journals (Sweden)

    Mona M.Jamjoom

    2016-05-01

    Full Text Available Noisy training data have a huge negative impact on machine learning algorithms. Noise-filtering algorithms have been proposed to eliminate such noisy instances. In this work, we empirically show that the most popular noise-filtering algorithms have a large False Positive (FP error rate. In other words, these noise filters mistakenly identify genuine instances as outliers and eliminate them. Therefore, we propose more conservative outlier identification criteria that improve the FP error rate and, thus, the performance of the noise filters. With the new filter, an instance is eliminated if and only if it is misclassified by a mutual decision of Naïve Bayesian (NB classifier and the original filtering criteria being used. The number of genuine instances that are incorrectly eliminated is reduced as a result, thereby improving the classification accuracy.

  10. Hybrid Filter Membrane

    Science.gov (United States)

    Laicer, Castro; Rasimick, Brian; Green, Zachary

    2012-01-01

    Cabin environmental control is an important issue for a successful Moon mission. Due to the unique environment of the Moon, lunar dust control is one of the main problems that significantly diminishes the air quality inside spacecraft cabins. Therefore, this innovation was motivated by NASA s need to minimize the negative health impact that air-suspended lunar dust particles have on astronauts in spacecraft cabins. It is based on fabrication of a hybrid filter comprising nanofiber nonwoven layers coated on porous polymer membranes with uniform cylindrical pores. This design results in a high-efficiency gas particulate filter with low pressure drop and the ability to be easily regenerated to restore filtration performance. A hybrid filter was developed consisting of a porous membrane with uniform, micron-sized, cylindrical pore channels coated with a thin nanofiber layer. Compared to conventional filter media such as a high-efficiency particulate air (HEPA) filter, this filter is designed to provide high particle efficiency, low pressure drop, and the ability to be regenerated. These membranes have well-defined micron-sized pores and can be used independently as air filters with discreet particle size cut-off, or coated with nanofiber layers for filtration of ultrafine nanoscale particles. The filter consists of a thin design intended to facilitate filter regeneration by localized air pulsing. The two main features of this invention are the concept of combining a micro-engineered straight-pore membrane with nanofibers. The micro-engineered straight pore membrane can be prepared with extremely high precision. Because the resulting membrane pores are straight and not tortuous like those found in conventional filters, the pressure drop across the filter is significantly reduced. The nanofiber layer is applied as a very thin coating to enhance filtration efficiency for fine nanoscale particles. Additionally, the thin nanofiber coating is designed to promote capture of

  11. Oriented Fiber Filter Media

    Directory of Open Access Journals (Sweden)

    R. Bharadwaj

    2008-06-01

    Full Text Available Coalescing filters are widely used throughout industry and improved performance will reduce droplet emissions and operating costs. Experimental observations show orientation of micro fibers in filter media effect the permeability and the separation efficiency of the filter media. In this work two methods are used to align the fibers to alter the filter structure. The results show that axially aligned fiber media improve quality factor on the order of 20% and cutting media on an angle from a thick layered media can improve performance by about 40%. The results also show the improved performance is not monotonically correlated to the average fiber angle of the medium.

  12. Fundamentals of Stochastic Filtering

    CERN Document Server

    Crisan, Dan

    2008-01-01

    The objective of stochastic filtering is to determine the best estimate for the state of a stochastic dynamical system from partial observations. The solution of this problem in the linear case is the well known Kalman-Bucy filter which has found widespread practical application. The purpose of this book is to provide a rigorous mathematical treatment of the non-linear stochastic filtering problem using modern methods. Particular emphasis is placed on the theoretical analysis of numerical methods for the solution of the filtering problem via particle methods. The book should provide sufficient

  13. Use of MAC-ELISA for evaluation of yellow fever vaccination Uso do MAC-ELISA para avaliação de vacinados contra febre amarela

    Directory of Open Access Journals (Sweden)

    Rita M. Ribeiro Nogueira

    1992-10-01

    Full Text Available An evaluation of the IgM antibody immune response against yellow fever using strain 17D was carried out by MAC-ELISA and PRNT. The results showed an agreement of 97% between both tests and the authors conclude that MAC-ELISA can be used as a specific and sensitive asssay to replace the PRNT for detecting yellow fever antibodies in human sera, after vaccination programs.Foi avaliada a resposta imune de anticorpos IgM em vacinados contra febre amarela usando a amostra 17D empregando-se provas de captura de anticorpos IgM (MAC-ELISA e teste de neutralização por redução de placas (PRNT. Os resulta-dos mostraram uma concordância de 97% entre ambas as provas e os autores concluem que o MAC-ELISA pode ser utilizado como um método específico e sensível para substituir o teste de neutralização para detecção de anticorpos IgM em vacinados contra febre amarela.

  14. Filter holder and gasket assembly for candle or tube filters

    Science.gov (United States)

    Lippert, Thomas Edwin; Alvin, Mary Anne; Bruck, Gerald Joseph; Smeltzer, Eugene E.

    1999-03-02

    A filter holder and gasket assembly for holding a candle filter element within a hot gas cleanup system pressure vessel. The filter holder and gasket assembly includes a filter housing, an annular spacer ring securely attached within the filter housing, a gasket sock, a top gasket, a middle gasket and a cast nut.

  15. The role of electron scattering from registration detector in the “Troitsk nu-mass” MAC-E type spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    Grigorieva, P.V. [Institute for Nuclear Research of Russian Academy of Sciences, prospekt 60-letiya Oktyabrya 7a, Moscow 117312 (Russian Federation); Moscow Institute of Physics and Technology, 9 Institutskiy per., Dolgoprudny, Moscow Region, 141700 (Russian Federation); Nozik, A.A., E-mail: nozik@inr.ru [Institute for Nuclear Research of Russian Academy of Sciences, prospekt 60-letiya Oktyabrya 7a, Moscow 117312 (Russian Federation); Moscow Institute of Physics and Technology, 9 Institutskiy per., Dolgoprudny, Moscow Region, 141700 (Russian Federation); Pantuev, V.S., E-mail: pantuev@inr.ru [Institute for Nuclear Research of Russian Academy of Sciences, prospekt 60-letiya Oktyabrya 7a, Moscow 117312 (Russian Federation); Skasyrskaya, A.K. [Institute for Nuclear Research of Russian Academy of Sciences, prospekt 60-letiya Oktyabrya 7a, Moscow 117312 (Russian Federation)

    2016-10-01

    There is a proposal to search for a sterile neutrino in a few keV mass range by the “Troitsk nu-mass” facility. In order to estimate sterile neutrino mixing one needs to make precision spectrum measurements well below the endpoint using the existing electrostatic spectrometer with a magnetic adiabatic collimation, or MAC-E filter. The expected signature will be a kink in the electron energy spectrum in tritium beta-decay. In this paper we consider the systematic effect of electron backscattering on the detector used in the spectrometer. For this purpose we provide a set of Monte-Carlo simulation results of electron backscattering on a silicon detector with a thin golden window with realistic electric and magnetic fields in the spectrometer. We have found that the probability of such an effect reaches up to 20–30%. The scattered electron could be reflected backwards to the detector by electrostatic field or by magnetic mirror. There is also a few percent probability to escape from the spectrometer through its entrance. A time delay between the scattering on the detector and the return of the reflected electron can reach a couple of microseconds in the Troitsk spectrometer. Such estimations are critical for the planning upgrades of the detector and the registration electronics. All considered effects are relevant to any MAC-E type spectrometer with solid detector.

  16. Characterization of the murine myeloid precursor cell line MuMac-E8.

    Science.gov (United States)

    Fricke, Stephan; Pfefferkorn, Cathleen; Wolf, Doris; Riemschneider, Sina; Kohlschmidt, Janine; Hilger, Nadja; Fueldner, Christiane; Knauer, Jens; Sack, Ulrich; Emmrich, Frank; Lehmann, Jörg

    2014-01-01

    Starting point for the present work was the assumption that the cell line MuMac-E8 represents a murine cell population with stem cell properties. Preliminary studies already pointed to the expression of stem-cell associated markers and a self-regenerative potential of the cells. The cell line MuMac-E8 should be examined for their differential stage within stem cell hierarchy. MuMac-E8 cells were derived from a chimeric mouse model of arthritis. It could be shown that MuMac-E8 cells express mRNA of some genes associated with pluripotent stem cells (Nanog, Nucleostemin), of genes for hematopoietic markers (EPCR, Sca-1, CD11b, CD45), for the mesenchymal marker CD105 and of genes for the neural markers Pax-6 and Ezrin. In methylcellulose and May-Grünwald-Giemsa staining, hematopoietic colonies were obtained but the hematopoietic system of lethally irradiated mice could not be rescued. Osteogenic differentiation was not detectable. Thus, it became evident that MuMac-E8 represents not a stem cell line. However, MuMac-E8 cells expressed several myeloid surface markers (i.e. CD11b, F4/80, CD14, CD64), showed phagocytosis and is capable of producing nitric oxide. Thus, this cell line seems to be arrested an advanced stage of myeloid differentiation. Adherence data measured by impedance-based real-time cell analysis together with cell morphology data suggested that MuMac-E8 represents a new macrophage precursor cell line exhibiting weak adherence. This cell line is suitable as an in-vitro model for testing of macrophage functions. Moreover, it might be also useful for differentiation or reprogramming studies.

  17. Characterization of the murine myeloid precursor cell line MuMac-E8.

    Directory of Open Access Journals (Sweden)

    Stephan Fricke

    Full Text Available Starting point for the present work was the assumption that the cell line MuMac-E8 represents a murine cell population with stem cell properties. Preliminary studies already pointed to the expression of stem-cell associated markers and a self-regenerative potential of the cells. The cell line MuMac-E8 should be examined for their differential stage within stem cell hierarchy. MuMac-E8 cells were derived from a chimeric mouse model of arthritis. It could be shown that MuMac-E8 cells express mRNA of some genes associated with pluripotent stem cells (Nanog, Nucleostemin, of genes for hematopoietic markers (EPCR, Sca-1, CD11b, CD45, for the mesenchymal marker CD105 and of genes for the neural markers Pax-6 and Ezrin. In methylcellulose and May-Grünwald-Giemsa staining, hematopoietic colonies were obtained but the hematopoietic system of lethally irradiated mice could not be rescued. Osteogenic differentiation was not detectable. Thus, it became evident that MuMac-E8 represents not a stem cell line. However, MuMac-E8 cells expressed several myeloid surface markers (i.e. CD11b, F4/80, CD14, CD64, showed phagocytosis and is capable of producing nitric oxide. Thus, this cell line seems to be arrested an advanced stage of myeloid differentiation. Adherence data measured by impedance-based real-time cell analysis together with cell morphology data suggested that MuMac-E8 represents a new macrophage precursor cell line exhibiting weak adherence. This cell line is suitable as an in-vitro model for testing of macrophage functions. Moreover, it might be also useful for differentiation or reprogramming studies.

  18. Word-serial Architectures for Filtering and Variable Rate Decimation

    Directory of Open Access Journals (Sweden)

    Eugene Grayver

    2002-01-01

    Full Text Available A new flexible architecture is proposed for word-serial filtering and variable rate decimation/interpolation. The architecture is targeted for low power applications requiring medium to low data rate and is ideally suited for implementation on either an ASIC or an FPGA. It combines the small size and low power of an ASIC with the programmability and flexibility of a DSP. An efficient memory addressing scheme eliminates the need for power hungry shift registers and allows full reconfiguration. The decimation ratio, filter length and filter coefficients can all be changed in real time. The architecture takes advantage of coefficient symmetries in linear phase filters and in polyphase components.

  19. An energy-efficient MAC protocol using dynamic queue management for delay-tolerant mobile sensor networks.

    Science.gov (United States)

    Li, Jie; Li, Qiyue; Qu, Yugui; Zhao, Baohua

    2011-01-01

    Conventional MAC protocols for wireless sensor network perform poorly when faced with a delay-tolerant mobile network environment. Characterized by a highly dynamic and sparse topology, poor network connectivity as well as data delay-tolerance, delay-tolerant mobile sensor networks exacerbate the severe power constraints and memory limitations of nodes. This paper proposes an energy-efficient MAC protocol using dynamic queue management (EQ-MAC) for power saving and data queue management. Via data transfers initiated by the target sink and the use of a dynamic queue management strategy based on priority, EQ-MAC effectively avoids untargeted transfers, increases the chance of successful data transmission, and makes useful data reach the target terminal in a timely manner. Experimental results show that EQ-MAC has high energy efficiency in comparison with a conventional MAC protocol. It also achieves a 46% decrease in packet drop probability, 79% increase in system throughput, and 25% decrease in mean packet delay.

  20. Fast Anisotropic Gauss Filtering

    NARCIS (Netherlands)

    Geusebroek, J.M.; Smeulders, A.W.M.; van de Weijer, J.; Heyden, A.; Sparr, G.; Nielsen, M.; Johansen, P.

    2002-01-01

    We derive the decomposition of the anisotropic Gaussian in a one dimensional Gauss filter in the x-direction followed by a one dimensional filter in a non-orthogonal direction phi. So also the anisotropic Gaussian can be decomposed by dimension. This appears to be extremely efficient from a computin

  1. Multilevel ensemble Kalman filter

    KAUST Repository

    Chernov, Alexey

    2016-01-06

    This work embeds a multilevel Monte Carlo (MLMC) sampling strategy into the Monte Carlo step of the ensemble Kalman filter (EnKF). In terms of computational cost vs. approximation error the asymptotic performance of the multilevel ensemble Kalman filter (MLEnKF) is superior to the EnKF s.

  2. Updating the OMERACT filter

    DEFF Research Database (Denmark)

    Wells, George; Beaton, Dorcas E; Tugwell, Peter;

    2014-01-01

    The "Discrimination" part of the OMERACT Filter asks whether a measure discriminates between situations that are of interest. "Feasibility" in the OMERACT Filter encompasses the practical considerations of using an instrument, including its ease of use, time to complete, monetary costs, and inter...

  3. On the filter approach to perceptual transparency.

    Science.gov (United States)

    Faul, Franz; Ekroll, Vebjørn

    2011-06-09

    In F. Faul and V. Ekroll (2002), we proposed a filter model of perceptual transparency that describes typical color changes caused by optical filters and accurately predicts perceived transparency. Here, we provide a more elaborate analysis of this model: (A) We address the question of how the model parameters can be estimated in a robust way. (B) We show that the parameters of the original model, which are closely related to physical properties, can be transformed into the alternative parameters hue H, saturation S, transmittance V, and clarity C that better reflect perceptual dimensions of perceived transparency. (C) We investigate the relation of H, S, V, and C to the physical parameters of optical filters and show that C is closely related to the refractive index of the filter, whereas V and S are closely related to its thickness. We also demonstrate that the latter relationship can be used to estimate relative filter thickness from S and V. (D) We investigate restrictions on S that result from properties of color space and determine its distribution under realistic choices of physical parameters. (E) We experimentally determine iso-saturation curves that yield nominal saturation values for filters of different hue such that they appear equally saturated.

  4. Vena cava filter; Vena-cava-Filter

    Energy Technology Data Exchange (ETDEWEB)

    Helmberger, T. [Klinikum Bogenhausen, Institut fuer Diagnostische und Interventionelle Radiologie und Nuklearmedizin, Muenchen (Germany)

    2007-05-15

    Fulminant pulmonary embolism is one of the major causes of death in the Western World. In most cases, deep leg and pelvic venous thrombosis are the cause. If an anticoagulant/thrombotic therapy is no longer possible or ineffective, a vena cava filter implant may be indicated if an embolism is threatening. Implantation of the filter is a simple and safe intervention. Nevertheless, it is necessary to take into consideration that the data base for determining the indications for this treatment are very limited. Currently, a reduction in the risk of thromboembolism with the use of filters of about 30%, of recurrences of almost 5% and fatal pulmonary embolism of 1% has been reported, with a risk of up to 20% of filter induced vena cava thrombosis. (orig.) [German] Die fulminante Lungenembolie zaehlt zu den Haupttodesursachen in der westlichen Welt. In der Mehrzahl der Faelle sind tiefe Bein- und Beckenvenenthrombosen ursaechlich verantwortlich. Ist eine antikoagulative/-thrombotische Therapie nicht (mehr) moeglich oder unwirksam, kann bei drohender Emboliegefahr die Vena-cava-Filterimplantation indiziert sein. Die Filterimplantation ist eine einfache und sehr sichere Intervention. Dennoch muss bei der Indikationsstellung beruecksichtigt werden, dass die Datenlage zur Wirksamkeit sehr limitiert ist. So wird aktuell ueber eine Reduktion des Thrombembolierisikos um 30% bei Embolierezidiven von knapp 5% und fatalen Lungenembolien von 1% unter Filterprophylaxe berichtet, bei einem Risiko von bis zu 20% fuer die filterinduzierte Vena-cava-Thrombose. (orig.)

  5. Plasma filtering techniques for nuclear waste remediation

    CERN Document Server

    Gueroult, Renaud; Fisch, Nathaniel J

    2015-01-01

    Nuclear waste cleanup is challenged by the handling of feed stocks that are both unknown and complex. Plasma filtering, operating on dissociated elements, offers advantages over chemical methods in processing such wastes. The costs incurred by plasma mass filtering for nuclear waste pretreatment, before ultimate disposal, are similar to those for chemical pretreatment. However, significant savings might be achieved in minimizing the waste mass. This advantage may be realized over a large range of chemical waste compositions, thereby addressing the heterogeneity of legacy nuclear waste.

  6. Plasma filtering techniques for nuclear waste remediation.

    Science.gov (United States)

    Gueroult, Renaud; Hobbs, David T; Fisch, Nathaniel J

    2015-10-30

    Nuclear waste cleanup is challenged by the handling of feed stocks that are both unknown and complex. Plasma filtering, operating on dissociated elements, offers advantages over chemical methods in processing such wastes. The costs incurred by plasma mass filtering for nuclear waste pretreatment, before ultimate disposal, are similar to those for chemical pretreatment. However, significant savings might be achieved in minimizing the waste mass. This advantage may be realized over a large range of chemical waste compositions, thereby addressing the heterogeneity of legacy nuclear waste.

  7. Sparse adaptive filters for echo cancellation

    CERN Document Server

    Paleologu, Constantin

    2011-01-01

    Adaptive filters with a large number of coefficients are usually involved in both network and acoustic echo cancellation. Consequently, it is important to improve the convergence rate and tracking of the conventional algorithms used for these applications. This can be achieved by exploiting the sparseness character of the echo paths. Identification of sparse impulse responses was addressed mainly in the last decade with the development of the so-called ``proportionate''-type algorithms. The goal of this book is to present the most important sparse adaptive filters developed for echo cancellati

  8. Robustifying Vector Median Filter

    Directory of Open Access Journals (Sweden)

    Valentín Gregori

    2011-08-01

    Full Text Available This paper describes two methods for impulse noise reduction in colour images that outperform the vector median filter from the noise reduction capability point of view. Both methods work by determining first the vector median in a given filtering window. Then, the use of complimentary information from componentwise analysis allows to build robust outputs from more reliable components. The correlation among the colour channels is taken into account in the processing and, as a result, a more robust filter able to process colour images without introducing colour artifacts is obtained. Experimental results show that the images filtered with the proposed method contain less noisy pixels than those obtained through the vector median filter. Objective measures demonstrate the goodness of the achieved improvement.

  9. Filter cake breaker systems

    Energy Technology Data Exchange (ETDEWEB)

    Garcia, Marcelo H.F. [Poland Quimica Ltda., Duque de Caxias, RJ (Brazil)

    2004-07-01

    Drilling fluids filter cakes are based on a combination of properly graded dispersed particles and polysaccharide polymers. High efficiency filter cakes are formed by these combination , and their formation on wellbore walls during the drilling process has, among other roles, the task of protecting the formation from instantaneous or accumulative invasion of drilling fluid filtrate, granting stability to well and production zones. Filter cake minimizes contact between drilling fluid filtrate and water, hydrocarbons and clay existent in formations. The uniform removal of the filter cake from the entire interval is a critical factor of the completion process. The main methods used to breaking filter cake are classified into two groups, external or internal, according to their removal mechanism. The aim of this work is the presentation of these mechanisms as well their efficiency. (author)

  10. Naive Bayesian for Email Filtering

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The paper presents a method of email filter based on Naive Bayesian theory that can effectively filter junk mail and illegal mail. Furthermore, the keys of implementation are discussed in detail. The filtering model is obtained from training set of email. The filtering can be done without the users specification of filtering rules.

  11. 42 CFR 405.1104 - Request for MAC review when an ALJ does not issue a decision timely.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 2 2010-10-01 2010-10-01 false Request for MAC review when an ALJ does not issue a...) Medicare Appeals Council Review § 405.1104 Request for MAC review when an ALJ does not issue a decision... under § 405.1016 may request MAC review if— (1) The appellant files a written request with the ALJ to...

  12. Eliminating the Heart from the Curcumin Molecule: Monocarbonyl Curcumin Mimics (MACs

    Directory of Open Access Journals (Sweden)

    Dinesh Shetty

    2014-12-01

    Full Text Available Curcumin is a natural product with several thousand years of heritage. Its traditional Asian application to human ailments has been subjected in recent decades to worldwide pharmacological, biochemical and clinical investigations. Curcumin’s Achilles heel lies in its poor aqueous solubility and rapid degradation at pH ~ 7.4. Researchers have sought to unlock curcumin’s assets by chemical manipulation. One class of molecules under scrutiny are the monocarbonyl analogs of curcumin (MACs. A thousand plus such agents have been created and tested primarily against cancer and inflammation. The outcome is clear. In vitro, MACs furnish a 10–20 fold potency gain vs. curcumin for numerous cancer cell lines and cellular proteins. Similarly, MACs have successfully demonstrated better pharmacokinetic (PK profiles in mice and greater tumor regression in cancer xenografts in vivo than curcumin. The compounds reveal limited toxicity as measured by murine weight gain and histopathological assessment. To our knowledge, MAC members have not yet been monitored in larger animals or humans. However, Phase 1 clinical trials are certainly on the horizon. The present review focuses on the large and evolving body of work in cancer and inflammation, but also covers MAC structural diversity and early discovery for treatment of bacteria, tuberculosis, Alzheimer’s disease and malaria.

  13. Cooperative Defense Against Pollution Attacks in Network Coding Using SpaceMac

    CERN Document Server

    Le, Anh

    2011-01-01

    Intra-session network coding is known to be vulnerable to pollution attacks. In this work, first, we introduce a novel homomorphic MAC scheme called SpaceMac, which allows an intermediate node to verify if its received packets belong to a specific subspace, even if the subspace is expanding over time. Then, we use SpaceMac as a building block to design a cooperative scheme that provides complete defense against pollution attacks: (i) it can detect polluted packets early at intermediate nodes and (ii) it can identify the exact location of all, even colluding, attackers, thus making it possible to eliminate them. Our scheme is cooperative: parents and children of any node cooperate to detect any corrupted packets sent by the node, and nodes in the network cooperate with a central controller to identify the exact location of all attackers. We implement SpaceMac in both C/C++ and Java as a library, and we make the library available online. Our evaluation on both a PC and an Android device shows that (i) SpaceMac'...

  14. Silicon Nanostructures Produced by Modified MacEtch Method for Antireflective Si Surface.

    Science.gov (United States)

    Nichkalo, Stepan; Druzhinin, Anatoly; Evtukh, Anatoliy; Bratus', Oleg; Steblova, Olga

    2017-12-01

    This work pertains to the method for modification of silicon (Si) wafer morphology by metal-assisted chemical etching (MacEtch) technique suitable for fabrication of antireflective Si surfaces. For this purpose, we made different Au catalyst patterns on the surface of Si substrate. This modification allowed to obtain the close-packed Au nanodrop (ND) pattern that generates the nanowires (NWs) and the well-separated Au NDs, which induce the nanopore (NP) formation. The antireflective properties of these structures in comparison with NWs produced by the conventional Ag-MacEtch method were analysed. The total surface reflectance of 1~7% for SiNWs and ~17% for SiNPs was observed over the entire Si-absorbing region. Moreover, SiNWs prepared by Au-MacEtch demonstrate better antireflective properties in contrast to those formed by conventional Ag-assisted chemical etching. So, the use of SiNWs produced by the modified Au-MacEtch method as the antireflective material is favored over those prepared by Ag-MacEtch due to their higher light absorption and lower reflectance. The possible reason of these findings is discussed.

  15. Halothane concentrations required to block the cardiovascular responses to incision (MAC CVR) in infants and children.

    Science.gov (United States)

    Ishizawa, Y; Dohi, S

    1993-01-01

    The purpose of this study was to determine the halothane concentration in N2O required to block the cardiovascular responses to skin incision (MAC CVR) in infants and children. We studied 64 unpremedicated ASA 1 infants and children (one month to seven years). In each infant or child, anaesthesia was induced slowly with halothane and N2O, and an endotracheal tube was placed. The MAC CVR was assessed, after a steady state end-tidal halothane concentration had been established for ten minutes, by the "up and down technique" of Dixon. Positive responses were defined as an increase in MAP or HR > 10%. The MAC CVR50 values of halothane with 60% N2O were 1.16 +/- 0.23% at 1-6 mo, 1.17 +/- 0.18% at 7-12 mo, 0.95 +/- 0.26% at 1-3 yr, and 1.12 +/- 0.16% at 4-7 yr. The value at 1-3 years children was less than those in the other age groups (P values of MAC CVR50 of halothane in infants and children are higher than those required to block motor responses (MAC). The halothane requirement to block cardiovascular responses is lowest in the children aged one to three years.

  16. A macrophage activation switch (MAcS)-index for assessment of monocyte/macrophage activation

    DEFF Research Database (Denmark)

    Maniecki, Maciej Bogdan; Lauridsen, Mette; Knudsen, Troels Bygum

    2008-01-01

    of inflammatory markers (IL-1β, IL-6, IL-8, IL-10, and TNF-α) was determined by RT-qPCR. Normalized values of sCD163 and mCD163 were calculated by dividing each value by the median value of the healthy population. The MAcS-index was then calculated as the ratio between normalized sCD163 and normalized mCD163....... A MAcS-index > 1 indicates relative increase in sCD163 as compared to mCD163, suggested to reflect a predominant M1 activation.   RESULTS AND DISCUSSION: The MAcS-index of healthy individuals clustered around 1 (2.5-97.5 percentile: 0.28-3.11), whereas the MAcS-index of the patients varied from 0.......06 to 5139, with 4% below the 2.5 % limit of healthy individuals, and 60% above the 97.5 upper limit of healthy individuals.  The MAcS-index in infected patients (with assumed M1 activation) was clearly elevated. The index was significantly higher in patients with clinical signs of infection (median: 9...

  17. MAP, MAC, and vortex-rings configurations in the Weinberg-Salam model

    Science.gov (United States)

    Teh, Rosy; Ng, Ban-Loong; Wong, Khai-Ming

    2015-11-01

    We report on the presence of new axially symmetric monopoles, antimonopoles and vortex-rings solutions of the SU(2)×U(1) Weinberg-Salam model of electromagnetic and weak interactions. When the ϕ-winding number n = 1, and 2, the configurations are monopole-antimonopole pair (MAP) and monopole-antimonopole chain (MAC) with poles of alternating sign magnetic charge arranged along the z-axis. Vortex-rings start to appear from the MAP and MAC configurations when the winding number n = 3. The MAP configurations possess zero net magnetic charge whereas the MAC configurations possess net magnetic charge of 4 πn / e. In the MAP configurations, the monopole-antimonopole pair is bounded by the Z0 field flux string and there is an electromagnetic current loop encircling it. The monopole and antimonopole possess magnetic charges ± 4πn/e sin2θW respectively. In the MAC configurations there is no string connecting the monopole and the adjacent antimonopole and they possess magnetic charges ± 4 πn/e respectively. The MAC configurations possess infinite total energy and zero magnetic dipole moment whereas the MAP configurations which are actually sphalerons possess finite total energy and magnetic dipole moment. The configurations were investigated for varying values of Higgs self-coupling constant 0 ≤ λ ≤ 40 at Weinberg angle θW = π/4.

  18. Noniterative Design of 2-Channel FIR Orthogonal Filters

    Directory of Open Access Journals (Sweden)

    Jiménez M Elena Domínguez

    2007-01-01

    Full Text Available This paper addresses the problem of obtaining an explicit expression of all real FIR paraunitary filters. In this work, we present a general parameterization of 2-channel FIR orthogonal filters. Unlike other approaches which make use of a lattice structure, we show that our technique designs any orthogonal filter directly, with no need of iteration procedures. Moreover, in order to design an -tap 2-channel paraunitary filterbank, it suffices to choose independent parameters, and introduce them in a simple expression which provides the filter coefficients directly. Some examples illustrate how this new approach can be used for designing filters with certain desired properties. Further conditions can be eventually imposed on the parameters so as to design filters for specific applications.

  19. LLCL-Filtered Grid Converter with Improved Stability and Robustness

    DEFF Research Database (Denmark)

    Min, Huang; Wang, Xiongfei; Loh, Poh Chiang

    2016-01-01

    impedance variations, making its design more challenging. To address these concerns, a new parameter design method for LLCL-filter has been formulated in the paper, which when enforced, guarantees robust and stable grid current control regardless of how the grid conditions change. It is thus an enhanced......LLCL-filter has been proven to introduce more filtering at the converter switching frequency, while using smaller passive components. However, like other higher order filters, it introduces resonance to the grid when used with a grid converter. Its stability and robustness are also affected by grid...... method even with no damping added to the grid converter. The method has been applied to the development of an LLCL-filter for testing in the laboratory with a 5-kW, 400-V, and 50-Hz grid converter. The method can also be applied to the lower order LCL-filter with only a slight modification needed....

  20. CONTENT-ADDRESSABLE MEMORY SYSTEMS,

    Science.gov (United States)

    The utility of content -addressable memories (CAM’s) within a general purpose computing system is investigated. Word cells within CAM may be...addressed by the character of all or a part of cell contents . Multimembered sets of word cells may be addressed simultaneously. The distributed logical...capabilities of CAM are extended to allow simultaneous transformation of multimembered sets and to allow communication between neighboring word cells. A

  1. Reclaiming unused IPv4 addresses

    CERN Multimedia

    IT Department

    2016-01-01

    As many people might know, the number of IPv4 addresses is limited and almost all have been allocated (see here and here for more information).   Although CERN has been allocated some 340,000 addresses, the way these are allocated across the site is not as efficient as we would like. As we face an increasing demand for IPv4 addresses with the growth in virtual machines, the IT Department’s Communication Systems Group will be reorganising address allocation during 2016 to make more efficient use of the IPv4 address ranges that have been allocated to CERN. We aim, wherever possible, to avoid giving out fixed IP addresses, and have all devices connected to the campus network obtain an address dynamically each time they connect. As a first stage, starting in February, IP addresses that have not been used for more than 9 months will be reclaimed. No information about the devices concerned will be deleted from LANDB, but a new IP address will have to be requested if they are ever reconnected to t...

  2. 2015 ASHG Awards and Addresses

    Science.gov (United States)

    2016-01-01

    Each year at the annual meeting of The American Society of Human Genetics (ASHG), addresses are given in honor of The Society and a number of award winners. A summary of each of these is given below. On the following pages, we have printed the presidential address and the addresses for the William Allan Award, the Curt Stern Award, and the Victor A. McKusick Leadership Award. Webcasts of these addresses, as well as those of many other presentations, can be found at http://www.ashg.org.

  3. Low power listening MAC protocol with collision avoidance and traffic adaption%带冲突避免和流量自适应的低功耗侦听MAC协议

    Institute of Scientific and Technical Information of China (English)

    彭昌睿; 黄宏光

    2013-01-01

    为提升无线传感器网络在能耗、时延以及动态适应负载方面的综合性能,对几种典型MAC协议进行了分析,提出了一种带冲突避免和流量自适应的LCT-MAC协议.在该协议中,长前导码被划分为多个小前导码,并嵌入目的节点地址信息,避免了串音;节点可以根据网络流量调整睡眠周期,减少了时延;在重负载时,节点能基于优先级信息选择退避时长,避免冲突.仿真结果表明,与S-MAC协议和LPL协议相比,LCT-MAC协议降低了传输时延,并减少了全网能耗和数据包碰撞次数,具有优良的综合性能.%To improve performance of wireless sensor networks in terms of energy consumption,network latency and traffic adaption,this paper proposed LCT-MAC with collision avoidance and traffic adaption through analyzing some classic MAC protocols.This protocol divided the long preamble into lots of small ones embedded with destination address to avoid crosstalk,and adjusted nodes sleep cycle according to traffic loads dynamically,and chose proper backoff time to avoid message collisions on the basis of nodes' priority.Simulations demonstrate that LCT-MAC is superior to both S-MAC and LPL in aspects of network latency,energy consumption as well as message collision,and has a good performance.

  4. Derivative free filtering using Kalmtool

    DEFF Research Database (Denmark)

    Bayramoglu, Enis; Hansen, Søren; Ravn, Ole;

    2010-01-01

    In this paper we present a toolbox enabling easy evaluation and comparison of different filtering algorithms. The toolbox is called Kalmtool 4 and is a set of MATLAB tools for state estimation of nonlinear systems. The toolbox contains functions for extended Kalman filtering as well as for DD1...... filter and the DD2 filter. It also contains functions for Unscented Kalman filters as well as several versions of particle filters. The toolbox requires MATLAB version 7, but no additional toolboxes are required....

  5. Circuits and filters handbook

    CERN Document Server

    Chen, Wai-Kai

    2003-01-01

    A bestseller in its first edition, The Circuits and Filters Handbook has been thoroughly updated to provide the most current, most comprehensive information available in both the classical and emerging fields of circuits and filters, both analog and digital. This edition contains 29 new chapters, with significant additions in the areas of computer-aided design, circuit simulation, VLSI circuits, design automation, and active and digital filters. It will undoubtedly take its place as the engineer's first choice in looking for solutions to problems encountered in the design, analysis, and behavi

  6. EMI filter design

    CERN Document Server

    Ozenbaugh, Richard Lee

    2011-01-01

    With today's electrical and electronics systems requiring increased levels of performance and reliability, the design of robust EMI filters plays a critical role in EMC compliance. Using a mix of practical methods and theoretical analysis, EMI Filter Design, Third Edition presents both a hands-on and academic approach to the design of EMI filters and the selection of components values. The design approaches covered include matrix methods using table data and the use of Fourier analysis, Laplace transforms, and transfer function realization of LC structures. This edition has been fully revised

  7. Randomized Filtering Algorithms

    DEFF Research Database (Denmark)

    Katriel, Irit; Van Hentenryck, Pascal

    2008-01-01

    of AllDifferent and is generalization, the Global Cardinality Constraint. The first delayed filtering scheme is a Monte Carlo algorithm: its running time is superior, in the worst case, to that of enforcing are consistency after every domain event, while its filtering effectiveness is analyzed...... in the expected sense. The second scheme is a Las Vegas algorithm using filtering triggers: Its effectiveness is the same as enforcing are consistency after every domain event, while in the expected case it is faster by a factor of m/n, where n and m are, respectively, the number of nodes and edges...

  8. A network architecture for precision formation flying using the IEEE 802.11 MAC Protocol

    Science.gov (United States)

    Clare, Loren P.; Gao, Jay L.; Jennings, Esther H.; Okino, Clayton

    2005-01-01

    Precision Formation Flying missions involve the tracking and maintenance of spacecraft in a desired geometric formation. The strong coupling of spacecraft in formation flying control requires inter-spacecraft communication to exchange information. In this paper, we present a network architecture that supports PFF control, from the initial random deployment phase to the final formation. We show that a suitable MAC layer for the application protocol is IEEE's 802.11 MAC protocol. IEEE 802.11 MAC has two modes of operations: DCF and PCF. We show that DCF is suitable for the initial deployment phase while switching to PCF when the spacecraft are in formation improves jitter and throughput. We also consider the effect of routing on protocol performance and suggest when it is profitable to turn off route discovery to achieve better network performance.

  9. MAC-layer protocol for TCP fairness in Wireless Mesh Networks

    KAUST Repository

    Nawab, Faisal

    2012-08-01

    In this paper we study the interactions of TCP and IEEE 802.11 MAC in Wireless Mesh Networks (WMNs). We use a Markov chain to capture the behavior of TCP sessions, particularly the impact on network throughput performance due to the effect of queue utilization and packet relaying. A closed form solution is derived to numerically determine the throughput. Based on the developed model, we propose a distributed MAC protocol to alleviate the unfairness problem in WMNs. Our protocol uses the age of packet as a priority metric for packet scheduling. Simulation is conducted to validate our model and to illustrate the fairness characteristics of our proposed MAC protocol. We conclude that we can achieve fairness with only little impact on network capacity.

  10. RMAC: A Reliable MAC Protocol Supporting Multicast for Wireless Ad Hoc Networks

    Institute of Scientific and Technical Information of China (English)

    Wei-Sheng Si; Cheng-Zhi Li

    2005-01-01

    This paper presents a new reliable MAC protocol called "RMAC" supporting reliable multicast for wireless ad hoc networks. By utilizing the busy tones to realize the multicast reliability, RMAC has three novelties: (1) it uses a variablelength control frame to stipulate an order for the receivers to respond, thus solving the feedback collision problem; (2) it extends the usage of busy tone for preventing data frame collisions into the multicast scenario; and (3) it introduces a new usage of busy tone for acknowledging data frames positively. In addition, RMAC is generalized into a comprehensive MAC protocol that provides both reliable and unreliable services for all the three modes of communications: unicast, multicast,and broadcast, making it capable of supporting various upper-layer protocols. The evaluation shows that RMAC achieves high reliability with very limited overhead. RMAC is also compared with other reliable MAC protocols, showing that RMAC not only provides higher reliability but also involves lower cost.

  11. The international epidemiology of disseminated Mycobacterium avium complex infection in AIDS. International MAC Study Group.

    Science.gov (United States)

    Fordham von Reyn, C; Arbeit, R D; Tosteson, A N; Ristola, M A; Barber, T W; Waddell, R; Sox, C H; Brindle, R J; Gilks, C F; Ranki, A; Bartholomew, C; Edwards, J; Falkinham, J O; O'Connor, G T

    1996-08-01

    To determine rates of disseminated Mycobacterium avium complex (MAC) infection among AIDS patients in developed and developing countries, and to determine whether different rates reflect differences in exposure or immunity, or both. Prospective cohort study. University hospitals and outpatient AIDS programs. HIV-infected subjects with CD4 counts or = 5 mm were present in 20% of patients from Kenya compared to 1% at other sites (P swimming in an indoor pool, history of bronchoscopy, regular consumption of raw or partially cooked fish/shellfish and treatment with granulocyte colony-stimulating factor. Rates of disseminated MAC in AIDS are higher in developed than developing countries and are due to both differences in exposure and differences in immunity. These data provide a rationale for prevention of MAC through both active immunization and reduction in exposure to the organism.

  12. Performance evaluation of IEEE 802.11 MAC layer in supporting delay sensitive services

    Directory of Open Access Journals (Sweden)

    Jyotsna Sengupta

    2010-02-01

    Full Text Available Providing QoS requirements like good throughput and minimum access delay are challenging tasks with regard to 802.11 WLAN protocols and Medium Access Control (MAC functions. IEEE 802.11 MAC layer supports two main protocols: DCF (Distributed Coordination Function and EDCF (Enhanced Distributed Coordination Function. During the evaluation of EDCF, the performance of various access categories was thedetermining factor. Two scenarios, with same Physical and MAC parameters, one implementing the DCF and other EDCF, were created in the network simulation tool (OPNET MODELER [5] to obtain the results. The results showed that the performance of EDCF was better in providing QoS for real-time interactive services (like video conferencing as compared to DCF, because of its ability to differentiate and prioritize various services. Whereas the DCF’s overall performance was marginally better for all kinds of services taken together.

  13. A MAC protocol for medical monitoring applications of wireless body area networks.

    Science.gov (United States)

    Shu, Minglei; Yuan, Dongfeng; Zhang, Chongqing; Wang, Yinglong; Chen, Changfang

    2015-06-03

    Targeting the medical monitoring applications of wireless body area networks (WBANs), a hybrid medium access control protocol using an interrupt mechanism (I-MAC) is proposed to improve the energy and time slot utilization efficiency and to meet the data delivery delay requirement at the same time. Unlike existing hybrid MAC protocols, a superframe structure with a longer length is adopted to avoid unnecessary beacons. The time slots are mostly allocated to nodes with periodic data sources. Short interruption slots are inserted into the superframe to convey the urgent data and to guarantee the real-time requirements of these data. During these interruption slots, the coordinator can break the running superframe and start a new superframe. A contention access period (CAP) is only activated when there are more data that need to be delivered. Experimental results show the effectiveness of the proposed MAC protocol in WBANs with low urgent traffic.

  14. An Approach to Analyze Physical Memory Image File of Mac OS X

    Institute of Scientific and Technical Information of China (English)

    LiJuan Xu; LianHai Wang

    2014-01-01

    Memory analysis is one of the key techniques in computer live forensics. Especially, the analysis of a Mac OS X operating system’ s memory image file plays an important role in identifying the running status of an apple computer. However, how to analyze the image file without using extra”mach-kernel” file is one of the unsolved difficulties. In this paper, we firstly compare several approaches for physical memory acquisition and analyze the effects of each approach on physical memory. Then, we discuss the traditional methods for the physical memory file analysis of Mac OS X. A novel physical memory image file analysis approach without using extra“mach-kernel” file is proposed base on the discussion. We verify the performance of the new approach on Mac OS X 10�8�2. The experimental results show that the proposed approach is simpler and more practical than previous ones.

  15. Optimization of listening time of S-MAC for wireless sensor networks

    Institute of Scientific and Technical Information of China (English)

    LI Cheng; WANG Kui-ru; ZHANG Jin-long; ZHAO De-xin; LI Wang

    2009-01-01

    In wireless sensor networks, sensor nodes are usually battery-operated computing and sensing devices, hence operations are limited by the initially equipped batteries, which are hard to be recharged or replaced. In this sense, saving energy consumption becomes significant. As most energy waste is from the always-on wireless interface, S-MAC is suggested to reduce energy consumption by introducing periodic listen/sleep scheme. However, when designing the listening time, S-MAC fails to consider the traffic distribution factor. In this article, an optimization for this scheme is proposed based on the distribution model. Evaluations show that the optimized S-MAC achieves considerable improvement in energy and latency.

  16. Optimal sensor placement for maximum area coverage (MAC) for damage localization in composite structures

    Science.gov (United States)

    Thiene, M.; Sharif Khodaei, Z.; Aliabadi, M. H.

    2016-09-01

    In this paper an optimal sensor placement algorithm for attaining the maximum area coverage (MAC) within a sensor network is presented. The proposed novel approach takes into account physical properties of Lamb wave propagation (attenuation profile, direction dependant group velocity due to material anisotropy) and geometrical complexities (boundary reflections, presence of openings) of the structure. A feature of the proposed optimization approach lies in the fact that it is independent of characteristics of the damage detection algorithm (e.g. probability of detection) making it readily up-scalable to large complex composite structures such as aircraft stiffened composite panel. The proposed fitness function (MAC) is independent of damage parameters (type, severity, location). Statistical analysis carried out shows that the proposed optimum sensor network with MAC results in high probability of damage localization. Genetic algorithm is coupled with the fitness function to provide an efficient optimization strategy.

  17. Learn Objective-C on the Mac for OS X and iOS

    CERN Document Server

    Knaster, Scott; Malik, Waqar

    2012-01-01

    Learn to write apps for some of today's hottest technologies, including the iPhone and iPad (using iOS), as well as the Mac (using OS X). It starts with Objective-C, the base language on which the native iOS software development kit (SDK) and the OS X are based. Learn Objective-C on the Mac: For OS X and iOS, Second Edition updates a best selling book and is an extensive, newly updated guide to Objective-C. Objective-C is a powerful, object-oriented extension of C, making this update the perfect follow-up to Dave Mark's bestselling Learn C on the Mac. Whether you're an experienced C programmer

  18. Plasma filtering techniques for nuclear waste remediation

    Energy Technology Data Exchange (ETDEWEB)

    Gueroult, Renaud, E-mail: rgueroul@pppl.gov [Princeton Plasma Physics Laboratory, Princeton, NJ 08540 (United States); Hobbs, David T. [Savannah River National Laboratory, Aiken, SC 29808 (United States); Fisch, Nathaniel J. [Princeton Plasma Physics Laboratory, Princeton, NJ 08540 (United States)

    2015-10-30

    Highlights: • A detailed economic study on plasma mass filtering techniques is presented. • Comparison with chemical techniques shows similar costs for solid-waste pretreatment. • Significant savings potential is identified through superior waste minimization. - Abstract: Nuclear waste cleanup is challenged by the handling of feed stocks that are both unknown and complex. Plasma filtering, operating on dissociated elements, offers advantages over chemical methods in processing such wastes. The costs incurred by plasma mass filtering for nuclear waste pretreatment, before ultimate disposal, are similar to those for chemical pretreatment. However, significant savings might be achieved in minimizing the waste mass. This advantage may be realized over a large range of chemical waste compositions, thereby addressing the heterogeneity of legacy nuclear waste.

  19. The Visual Effects of Intraocular Colored Filters

    Directory of Open Access Journals (Sweden)

    Billy R. Hammond

    2012-01-01

    Full Text Available Modern life is associated with a myriad of visual problems, most notably refractive conditions such as myopia. Human ingenuity has addressed such problems using strategies such as spectacle lenses or surgical correction. There are other visual problems, however, that have been present throughout our evolutionary history and are not as easily solved by simply correcting refractive error. These problems include issues like glare disability and discomfort arising from intraocular scatter, photostress with the associated transient loss in vision that arises from short intense light exposures, or the ability to see objects in the distance through a veil of atmospheric haze. One likely biological solution to these more long-standing problems has been the use of colored intraocular filters. Many species, especially diurnal, incorporate chromophores from numerous sources (e.g., often plant pigments called carotenoids into ocular tissues to improve visual performance outdoors. This review summarizes information on the utility of such filters focusing on chromatic filtering by humans.

  20. WORKLOAD CHARACTERIZATION OF SPAM EMAIL FILTERING SYSTEMS

    Directory of Open Access Journals (Sweden)

    Yan Luo

    2010-01-01

    Full Text Available Email systems have suffered from degraded quality of service due to rampant spam, phishing and fraudulent emails. This is partly because the classification speed of email filtering systems falls far behindthe requirements of email service providers. We are motivated to address this issue from the perspective of computer architecture support. In this paper, as the first step towards novel architecture designs, we present extensive performance data collected from measurement and profiling experiments using representative email filtering systems including CRM114, DSPAM, SpamAssassin and TREC Bogofilter. We provide detailed analysis of the time consuming functions in the systems under study. We also show how the processor architecture parameters affect the performance of these email filters through simulation experiments.