These are representative sample records from Science.gov related to your search topic.
For comprehensive and current results, perform a real-time search at Science.gov.
1

Swinging Yo-Yo  

NSDL National Science Digital Library

Learners build a pendulum from a yo-yo, and then design their own experiment to determine what affects the pendulum's period of swing. They can alter the mass of the yo-yo by adding play dough, the length of the yo-yo string, or some other variable of their own choosing. Learners collect data and graph their results. This activity starts on p.17 of the manual. This manual contains 4 activities related to the Spectra's Force comic book published by the American Physical Society.

Rebecca Thompson

2011-01-01

2

Bouncing Yo-Yo  

NSDL National Science Digital Library

In this activity, learners build unique yo-yos, which spin round and round without moving up and down. Learners can construct their yo-yos out of wood using a saw and drill or more simply, out of a paper plate. Use this activity to explore angular motion, center of gravity, and energy. Note: a drill and saw may be used during this activity, but are not included in the cost of materials.

Workshop, Watsonville E.

2011-01-01

3

Yo-yo Pull Demonstration  

NASA Astrophysics Data System (ADS)

A popular demonstration involves placing a yo-yo on a level table and gently pulling the string horizontally when it is wrapped to come out below the center of the yo-yo's axis. Students are then asked to predict which way the yo-yo will move. A similar demonstration is performed with a tricycle by pulling forward on a pedal with the pedal down in its lowest position.2,3 As well as pulling the yo-yo horizontally, often the string is lifted until the angle it makes with the table causes no motion. This occurs when the line extended from the string intersects the point of contact of the yo-yo with the table.4 This paper describes an apparatus that extends these demonstrations to the situation where the force pulling the yo-yo is still horizontal yet is below the level of the table.

Layton, William

2013-03-01

4

The Yo-Yo Problem  

NSDL National Science Digital Library

In this math lesson, learners explore linear patterns, write a pattern in symbolic form, and solve linear equations using algebra tiles, symbolic manipulation, and a graphing calculator. The lesson begins with the presentation of the yo-yo problem. Then learners complete a hands-on activity involving a design created with pennies. Algebra tiles are introduced next as learners practice solving linear equations. Finally, learners return to solving the yo-yo problem.

Pbs

2012-01-01

5

Museum of Yo-Yo History  

NSDL National Science Digital Library

Perhaps no toy is as maligned as the yo-yo, despite its long and colorful history. The roots of the yo-yo can be traced back to antiquity, and there is even a Grecian urn in the collection of the Metropolitan Museum of Art that depicts that most well-known of yo-yo maneuvers: walking the dog. Visitors with a penchant for the yo-yo will appreciate the wide range of materials that can be found on the site, particularly the rather compelling online exhibit of highly valuable yo-yos, such as the 1984 Olympics No Jive model. For those who want to continue their exploration of the yo-yo, there is the âÂÂProfiles & Historyâ area, which contains player and company profiles, along with historical photographs of yo-yos in action.

2004-01-01

6

Mechanical study of a modern yo-yo  

Microsoft Academic Search

This paper presents the study of a modern yo-yo having a centrifugal clutch allowing the free rolling. First, the mechanical parts of the yo-yo are measured, allowing us to determine analytically its velocity according to its height of fall. Then, we are more particularly interested in the centrifugal device constituted by springs and small masses. The physics of this toy

Charles de Izarra

2011-01-01

7

Mechanical Study of a Modern Yo-Yo  

ERIC Educational Resources Information Center

This paper presents the study of a modern yo-yo having a centrifugal clutch allowing the free rolling. First, the mechanical parts of the yo-yo are measured, allowing us to determine analytically its velocity according to its height of fall. Then, we are more particularly interested in the centrifugal device constituted by springs and small…

de Izarra, Charles

2011-01-01

8

The Yo-Yo intermittent recovery test in basketball players.  

PubMed

The purpose of this study was to examine the physiological correlates of the Yo-Yo intermittent recovery test level 1 (Yo-Yo IR1) in basketball players. Twenty-two male basketball players (means+/-S.D., body mass 72.4+/-11.4kg, height 181.7+/-6.9cm, age 16.8+/-2.0 years) were tested for maximal oxygen uptake (VO(2max)), ventilatory threshold (VT) and running economy (RE) on a motorized treadmill. Lower limb explosive strength and anaerobic-capacity was assessed using vertical jumps (CMJ), 15m shuttle running sprint (15mSR) and line drill (LD), respectively. The same test battery was replicated after an experimental basketball game in order to assess selective effect of fatigue on physical performance. Pre to post-game CMJ (40.3+/-5.7 versus 39.9+/-5.9cm) and 15mSR (5.80+/-0.25 versus 5.77+/-0.22s) performances were not significantly different (p>0.05). LD performance decreased significantly post-game (from 26.7+/-1.3 to 27.7+/-2.7s, p<0.001). Yo-Yo IR1 performances (m) were significantly related to VO(2max) (r=0.77, p=0.0001), speed at VO(2max) (r=0.71, p=0.0001) and %VO(2max) at VT (r=-0.60, p=0.04). Yo-Yo IR1 performance was significantly correlated to post-game LD decrements (r=-0.52, p=0.02). These findings show that Yo-Yo IR1 may be considered as a valid basketball-specific test for the assessment of aerobic fitness and game-related endurance. PMID:17574917

Castagna, Carlo; Impellizzeri, Franco M; Rampinini, Ermanno; D'Ottavio, Stefano; Manzi, Vincenzo

2008-04-01

9

The Yo-Yo Problem: Solving Linear Equations  

NSDL National Science Digital Library

In this lesson, students explore linear patterns, write a pattern in symbolic form, and solve linear equations using algebra tiles, symbolic manipulation, and the graphing calculator. The lesson starts with the presentation of the yo-yo problem. Students then complete a hands-on activity involving a design created with pennies that allows them to explore a linear pattern and express that pattern in symbolic form. Algebra tiles are introduced as the students practice solving linear equations. Working from the concrete to the abstract is especially important for students who have difficulty with mathematics, and algebra tiles help students make this transition. In addition to using algebra tiles, students also use symbolic manipulation and the graphing calculator. Finally, the students return to solve the yo-yo problem. A feature of this lesson is the effective use of peer tutors in this inclusion classroom. Student worksheets are included to print.

2007-12-12

10

[A life of Ryu Sang-Kyu, a colonial modernized intellectual].  

PubMed

Many of the Korean intellectuals resisted against suppression of Japanese Imperialism with the people during the Japanese occupation period. Ryu Sang-Kyu was also one of those intellectuals. Ryu Sang-Kyu was born in Gang-gye of North Pyongan-do on 10th November, 1897. He entered Keijo Medical College as one of the first entering students in 1916. However, at the end of his third year, he participated in the 3.1 Independence Movement of Korea and was suspended from the college which was run by the Japanese on account of his participation. Then moving to Shanghai, he joined Heung Sa Dan, an active patriotic group fighting for independence of Korea. He initiated the provisional government of Korea as a network investigator and he played second string to Ahn Chang-Ho, one of major Korean independence activists for four years. In 1923, following Ahn Chang-Ho's advice, he returned to Keijo Medical College to complete the course. Even in colonial Korea, he continued independence movement and was involved in Dong Woo Hoe, the branch of Heung Sa Dan in Korea. After the graduation of Keijo Medical College in 1927, he had served at the department of surgery in Keijo Medical College. In 1930, he participated in founding of the Korean Medical Association. He also raised public awareness by writing to many articles on hygiene and public health issues in public journals and newspapers. In short, he did his best as an intellectual, a medical doctor, an activist of independence movement until he died from streptococcal infection on 7th July, 1936. PMID:20098056

Choi, Q Jin; Hwang, Sang Ik; Kim, Soo Youn

2009-12-01

11

Si, Yo Puedo Controlar Mi Diabetes!  

E-print Network

¡Si, Yo Puedo Controlar Mi Diabetes! ¡Si, Yo Puedo Controlar Mí Diabetes! (Si, Yo Puedo/Latinos with diabetes. The curriculum is predicated on the American Diabetes Association's national standards of care and lifestyle skills to better control their diabetes. Relevance · Diabetes costs Texas more than 12 billion

12

Exploring functional structure through system organization: Caenorhabditis elegans neuronal network  

E-print Network

Exploring functional structure through system organization: Caenorhabditis elegans neuronal network, systemic organization, modular structure, functional circuit #12; Hyeok Jung Kang1 , Myung-Kyu Choi2, Junho Lee2 , Namkyoo Park*1 *nkpark@snu.ac.kr 1 Photonic Systems

Park, Namkyoo

13

Acute effects of Yo-Yo intermittent recovery test level 1 (Yo-YoIR1) on hemorheological parameters in female volleyball players.  

PubMed

In the present study, we investigated possible alterations in red blood cell (RBC) deformability, plasma and whole blood viscosities (WBV) and hematological parameters in response to Yo-Yo intermittent recovery test level 1 (Yo-YoIR1) which is currently used to assess endurance performance, in female volleyball players. Eight volleyball player volunteers from Pamukkale University (mean age19,9 ± 2,2 years; mean body height 177.5 ± 1.99 cm; mean body mass index 21.66 ± 0.64 kg/m2) participated to the study. Blood samples were collected before and immediately after test. Red blood cell (RBC) deformability was determined by ektacytometer, plasma and whole blood viscosities (WBV) by a cone-plate rotational viscometer. Hematological parameters were determined using an electronic hematology analyzer. The Yo-YoIR1 applied, induced acute increments in WBV at native hematocrit (Hct) measured at a shear rate of 150 s-1 and 375 s-1, RBC deformability and WBC count. The results of the current study indicate that, the Yo-Yo IR1 test used to determine physical capacity of the player, by resulting in increments in RBC deformability contributes blood flow and thus, athletic performance of the individual. PMID:24840339

Kilic-Toprak, Emine; Yapici, Aysegul; Kilic-Erkek, Ozgen; Köklü, Yusuf; Tekin, Volkan; Alemdaroglu, Utku; Bor-Kucukatay, Melek

2014-05-19

14

Thermally Stable Gel Polymer Electrolytes Min-Kyu Song,a  

E-print Network

Thermally Stable Gel Polymer Electrolytes Min-Kyu Song,a Young-Taek Kim,a Yong Tae Kim,b Byung Won/polyvinylidene fluoride PEGDA/PVdF blend gel polymer electrolytes, low molecular weight (M 742) liquid PEGDA oligomer was mixed with PVdF-HFP dissolved in ethylene carbonate/dimethyl carbonate/LiPF6 liquid electrolytes

Popov, Branko N.

15

YO-3A parked on ramp  

NASA Technical Reports Server (NTRS)

NASA's YO-3A parked on the Dryden ramp. The YO-3A aircraft was originally a Schweizer SGS-2-23 sailplane. During the late 1960s Lockheed modified over a dozen of these sailplanes to create ultra-quiet observation aircraft for use over South Vietnam during the conflict there. This particular YO-3A flew combat missions and was later sold to an airframe and powerplant mechanics school. NASA's Ames Research Center at Mountain Veiw, California, acquired the aircraft from the school in 1978. It restored the YO-3A to flight status and fitted it with wing- and tail-mounted microphones as an accoustic research aircraft. Ames operated it at Edwards Air Force Base for noise measurements of helicopters and tilt rotor aircraft. One set of tests in December 1995 obtained free-flight noise data on the XV-15 tilt rotor. NASA also used the YO-3A for sonic boom measurements of a NASA SR-71 assigned to the Dryden Flight Research Center. NASA transferred the YO-3A to Dryden in December 1997, and as of April 2001 it was in flyable storage there. The designation YO-3A indicates that this aircraft was a pre-production (Y) observation (O) aircraft. Even though the YO-3A saw operational use, the Y designation was never removed. Its 210-horsepower Continental V-6 was modified to reduce noise. The engine was connected to a propeller through a belt-driven reduction system. This reduced the propeller's rotation speed. The propeller blades themselves were made of birch plywood and were wider than standard propellers. The result of these modifications was an aircraft so quiet that its noise was drowned out by the background sounds.

1997-01-01

16

Lasing in localized modes of a slow light photonic crystal waveguide Jin-Kyu Yang,1,2  

E-print Network

Lasing in localized modes of a slow light photonic crystal waveguide Jin-Kyu Yang,1,2 Heeso Noh,1 National University, Kongju 314-701, Republic of Korea 3 Joint Quantum Institute, NIST, University crystal waveguides with InAs quantum dots as gain medium. Structural disorder is present due

Cao, Hui

17

HUMAN DIVERSITY AND LANGUAGE DIVERSITY WILLIAM So-YoWANG  

E-print Network

dynastyand ruled the entirety of China for nearly 300 yearsHUMAN DIVERSITY AND LANGUAGE DIVERSITY WILLIAM So-YoWANG Departmentof still speakManchu.Thoseover thirty years old were likely to understandit

Wang, William Shi-Yuan

18

Toddlers’ choice: Yo-Yoing diabetes control or deci-unit insulin dosing?  

PubMed Central

While the incidence of toddlers’ diabetes is soaring, their mainstay insulins were withdrawn, namely the weak 10% or 20% insulin mixtures (WIM), which were injected only once or twice daily. Consequently, toddlers are coerced to use an insulin pump, multi-dose insulin regime (MuDIR), mix or dilute insulins. This paper highlights the difficulties and proposes a simple solution. While an insulin pump is the best available option, it is not readily available for everyone. Mixing insulins is not sufficiently precise in small doses. Although diluting insulin would allow precise dosing and reduce the dose variability secondary to dribbling after injections, it, like insulin mixing, deprives children from using the pen and related child-friendly accessories. In MuDIR, we inject 4-5 small doses of insulin instead of 1-2 daily larger doses of WIM. Thus, on using a half unit (½unit) insulin pen, a dose of 0.5, 1, 1.5 and 2 units are adjusted in steps of 100%, 50%, 33% or 25%; unlike the advisable 5%-20%. This does not easily match the tiny erratic meals of grazing toddlers. Maternal anxiety peaks on watching yo-yoing glycemia. Carers have to accept either persistently high sugar or wild fluctuation. The risks of such poor glycemic pattern are increasingly recognized. Using insulin U20 in a ½unit disposable pen allows deci-unit dosing, with 5%-20% dose-tuning, greater accuracy on delivering small doses and reduction of dose variability from dribbling. Deci-unit dosing may help avoid wide glycemic swings and provide the affordable alternative to insulin pumps for toddlers. Deci-unit pen materializes the Human Rights of Children, a safer and effective treatment. PMID:22375164

Abul-Ainine, Sarah AA; Abul-Ainine, Ahmad AA

2012-01-01

19

Fiber optic probe of free electron evanescent fields in the optical frequency range Jin-Kyu So, Kevin F. MacDonald, and Nikolay I. Zheludev  

E-print Network

Fiber optic probe of free electron evanescent fields in the optical frequency range Jin-Kyu So fabrication of bent near-field optical fiber probes by electric arc heating Rev. Sci. Instrum. 69, 3843 (1998 of thermal evaporation conditions used in coating aluminum on near-field fiber-optic probes Rev. Sci. Instrum

Zheludev, Nikolay

20

A STUDY ON THE EVOLUTION OF THE WEB Alexandros Ntoulas1, Junghoo Cho1, Hyun Kyu Cho2, Hyeonsung Cho2, and Young-Jo Cho2  

E-print Network

engine designers: the evolution of link structure over time and the rate of creation of new pagesA STUDY ON THE EVOLUTION OF THE WEB Alexandros Ntoulas1, Junghoo Cho1, Hyun Kyu Cho2, Hyeonsung Cho the evolution of content and link structure. Our measurements focus on aspects of potential interest to search

Cho, Junghoo "John"

21

Agent Program Planning Information S! Yo Puedo Controlar Mi Diabetes!  

E-print Network

Agent Program Planning Information Sí! ¡Yo Puedo Controlar Mi Diabetes! (A culturally appropriate type 2 diabetes self-management program for Hispanic/Latino, Spanish-speaking audiences) Relevance · Estimates from the Texas Health and Human Services Commission indicate that in 2011 diabetes cost Texas more

22

Evaluation of the Yo Puedo Summer Program--1985-86.  

ERIC Educational Resources Information Center

Designed for migrant students in grades 9 through 12, the Yo Puedo Program attempted to motivate students to remain in and graduate from high school and to continue their education at the university level. The 5-week summer program, conducted at the University of California at Santa Cruz, provided an academic setting and a positive learning…

Cognetta, Randall A.; Goodwine, Jean

23

Yo no soy Gayina 9 de junio de 2008  

E-print Network

secundario. River fue una aplanadora que aplast´o a los oponentes y en la segunda mi- 1 #12;tad del torneo. A pesar de que yo viv´ia en Mar del Plata, el domingo fuimos con mi viejo al estadio. Como olvidar aquella

Giménez de Castro, Guillermo Carlos

24

40 CFR 721.10013 - Manganese yttrium oxide (Mn2YO5).  

Code of Federal Regulations, 2011 CFR

...2011-07-01 false Manganese yttrium oxide (Mn2YO5). 721.10013 Section 721...Substances § 721.10013 Manganese yttrium oxide (Mn2YO5). (a) Chemical substance...substance identified as manganese yttrium oxide (Mn2 YO5 ) (PMN...

2011-07-01

25

40 CFR 721.10013 - Manganese yttrium oxide (Mn2YO5).  

...2014-07-01 false Manganese yttrium oxide (Mn2YO5). 721.10013 Section 721...Substances § 721.10013 Manganese yttrium oxide (Mn2 YO5 ). (a) Chemical substance...substance identified as manganese yttrium oxide (Mn2 YO5 ) (PMN...

2014-07-01

26

40 CFR 721.10009 - Manganese yttrium oxide (MnYO3).  

...2014-07-01 false Manganese yttrium oxide (MnYO3). 721.10009 Section 721...Substances § 721.10009 Manganese yttrium oxide (MnYO3 ). (a) Chemical substance...substance identified as manganese yttrium oxide (MnYO3 ) (PMN P-00-1122;...

2014-07-01

27

40 CFR 721.10009 - Manganese yttrium oxide (MnYO3).  

Code of Federal Regulations, 2012 CFR

...2012-07-01 false Manganese yttrium oxide (MnYO3). 721.10009 Section 721...Substances § 721.10009 Manganese yttrium oxide (MnYO3 ). (a) Chemical substance...substance identified as manganese yttrium oxide (MnYO3 ) (PMN P-00-1122;...

2012-07-01

28

40 CFR 721.10009 - Manganese yttrium oxide (MnYO3).  

Code of Federal Regulations, 2010 CFR

...2010-07-01 2010-07-01 false Manganese yttrium oxide (MnYO3). 721.10009...Chemical Substances § 721.10009 Manganese yttrium oxide (MnYO3). (a) Chemical...The chemical substance identified as manganese yttrium oxide (MnYO3 ) (PMN...

2010-07-01

29

40 CFR 721.10013 - Manganese yttrium oxide (Mn2YO5).  

Code of Federal Regulations, 2010 CFR

...2010-07-01 2010-07-01 false Manganese yttrium oxide (Mn2YO5). 721.10013...Chemical Substances § 721.10013 Manganese yttrium oxide (Mn2YO5). (a...The chemical substance identified as manganese yttrium oxide (Mn2 YO5 )...

2010-07-01

30

Synthesis, characterization and photocatalytic activity of new photocatalyst CdBiYO4  

NASA Astrophysics Data System (ADS)

CdBiYO4 was synthesized by a solid-state reaction method for the first time. The structural and photocatalytic properties of CdBiYO4 had been characterized by X-ray diffraction, scanning electron microscopy, X-ray photoelectron spectroscopy and X-ray spectrometry. CdBiYO4 crystallized with a tetragonal spinel structure by space group I41/amd. The lattice parameters for CdBiYO4 were a = b = 14.519 Å and c = 9.442 Å. The band gap of CdBiYO4 was estimated to be 2.41 eV. The photocatalytic degradation of methylene blue (MB) was realized under visible light irradiation with CdBiYO4 as catalyst. The results showed that CdBiYO4 owned higher photocatalytic activity compared with pure TiO2 or N-doped TiO2 for photocatalytic degradation of MB under visible light irradiation. The photocatalytic degradation of MB with CdBiYO4 or N-doped TiO2 as catalyst followed the first-order reaction kinetics, and the first-order rate constant was 0.0137 or 0.0033 min-1. After visible light irradiation for 225 min with CdBiYO4 as catalyst, complete removal and mineralization of MB were observed. The reduction of the total organic carbon, the formation of inorganic products, SO42- and NO3-, and the evolution of CO2 revealed the continuous mineralization of MB during the photocatalytic process. The possible photocatalytic degradation pathway of MB was obtained under visible light irradiation. CdBiYO4/(visible light) photocatalysis system was found to be suitable for textile industry wastewater treatment and could be utilized to resolve other environmental chemical pollution problems.

Du, Huiyang; Luan, Jingfei

2012-09-01

31

Rydberg and pulsed field ionization-zero electron kinetic energy spectra of YO  

Microsoft Academic Search

A spectroscopic study of the Rydberg states of YO accessed from\\u000a particular rotational levels of the A (2)Pi(1\\/2), v=0 state has been\\u000a combined with a pulsed field ionization, zero electron kinetic energy\\u000a (PFI-ZEKE) investigation. The results provide accurate values of the\\u000a ionization energy of YO, ionization energy I.E.(YO)=49 304.316(31)\\u000a cm(-1) {[}6.112 958(4) eV], and of the rotational constant (and bond

Colan Linton; Benoit Simard; HP Loock; Sara Wallin; Gretchen K. Rothschopf; Robert F. Gunion; Michael D. Morse; Peter B. Armentrout

1999-01-01

32

Synthesis and characterization of oxygen-rich delafossite CuYO 2+ x —Application to H 2photo production  

Microsoft Academic Search

Here we report the synthesis and photo electrochemical properties of super oxides CuYO2.50 and CuYO2.25 prepared from the delafossite CuYO2, respectively, by thermal oxidation at 380°C under O2-flow and soft chemistry in NaBrO solution (5N). Their applications as catalysts for H2 evolution upon visible light were investigated. The oxygen insertion was accompanied by partial oxidation of Cu+. For CuYO2.25, the

M. Younsi; S. Saadi; A. Bouguelia; A. Aider; M. Trari

2007-01-01

33

Thermodynamic Modeling of the YO(l.5)-ZrO2 System  

NASA Technical Reports Server (NTRS)

The YO1.5-ZrO2 system consists of five solid solutions, one liquid solution, and one intermediate compound. A thermodynamic description of this system is developed, which allows calculation of the phase diagram and thermodynamic properties. Two different solution models are used-a neutral species model with YO1.5 and ZrO2 as the components and a charged species model with Y(+3), Zr(+4), O(-2), and vacancies as components. For each model, regular and sub-regular solution parameters are derived fiom selected equilibrium phase and thermodynamic data.

Jacobson, Nathan S.; Liu, Zi-Kui; Kaufman, Larry; Zhang, Fan

2003-01-01

34

Build Brand yoU SM Strategies for Personal Brand Development  

E-print Network

Build Brand yoU SM Strategies for Personal Brand Development for the First Year College Student #12 college students This can be achieved by building your personal brand #12;ONTARGET What is a brand. #12;ONTARGET Popular Brands Your in good hands. AllState Have it your way. Burger King Just do it

Lin, Xiaodong

35

An Overview of Language Preservation at Ohi: Yo'., the Seneca Allegany Territory  

ERIC Educational Resources Information Center

This project seeks to discover and disseminate information pertaining to the language practices and values of a selected group of "Onodowa'ga:'" (Seneca) at "Ohi:yo'", or the Allegany Territory, in upstate New York. The goal is to find where the current practices and values are situated in the larger picture of Seneca preservation as well as the…

Borgia, Melissa E.

2010-01-01

36

The molecular yo-yo method: Live jump detection improves throughput of single-molecule force spectroscopy for out-of-equilibrium transitions  

NASA Astrophysics Data System (ADS)

By monitoring multiple molecular transitions, force-clamp, and trap-position-clamp methods have led to precise determinations of the free energies and free energy landscapes for molecular states populated in equilibrium at the same or similar forces. Here, we present a powerful new elaboration of the force-clamp and force-jump methods, applicable to transitions far from equilibrium. Specifically, we have implemented a live jump detection and force-clamp algorithm that intelligently adjusts and maintains the force on a single molecule in response to the measured state of that molecule. We are able to collect hundreds of individual molecular transitions at different forces, many times faster than previously, permitting us to accurately determine force-dependent lifetime distributions and reaction rates. Application of our method to unwinding and rewinding the nucleosome inner turn, using optical tweezers reveals experimental lifetime distributions that comprise a statistically meaningful number of transitions, and that are accurately single exponential. These measurements significantly reduce the error in the previously measured rates, and demonstrate the existence of a single, dominant free energy barrier at each force studied. A key benefit of the molecular yo-yo method for nucleosomes is that it reduces as far as possible the time spent in the tangentially bound state, which minimizes the loss of nucleosomes by dissociation.

Mack, A. H.; Schlingman, D. J.; Kamenetska, M.; Collins, R.; Regan, L.; Mochrie, S. G. J.

2013-08-01

37

New chrodrimanin congeners, chrodrimanins D-H, from YO-2 of Talaromyces sp.  

PubMed

Four new meroterpenoids, named chrodrimanins D-G (4-7), and one known compound, renamed chrodrimanin H (8), were isolated from okara (the insoluble residue of whole soybean) that had been fermented with the YO-2 strain of Talaromyces sp. Their structures were elucidated by spectroscopic methods. Chrodrimanins D (4), E (5), and F (6) showed insecticidal activity against silkworms with respective LD(50) values of 20, 10, and 50 µg/g of diet. PMID:22972343

Hayashi, Hideo; Oka, Yuki; Kai, Kenji; Akiyama, Kohki

2012-01-01

38

A new meroterpenoid, chrodrimanin C, from YO-2 of Talaromyces sp.  

PubMed

The new meroterpenoid, chrodrimanin C (3), together with chrodrimanins A (2) and B (1) were isolated from okara (the insoluble residue of whole soybean) that had been fermented with strain YO-2 of Talaromyces sp. Their structures were elucidated by spectroscopic methods. The partial structures of 1 essential for exhibiting insecticidal activity were investigated by using a silkworm assay. The absolute configuration of 1 was also determined. PMID:22484942

Hayashi, Hideo; Oka, Yuki; Kai, Kenji; Akiyama, Kohki

2012-01-01

39

Preparation of Delafossite-Type CuYO2 Films by Solution Method  

Microsoft Academic Search

The preparation of CuYO2 films on quartz glass substrates was carried out through the solution method using copper and yttrium nitrates as sources. Firstly, dip-coated films on the quartz glass substrates were annealed in air, and then annealed again under nitrogen flow. Continuous films were formed on the substrate surfaces. The films annealed in air at 900-950 °C were almost

Nozomu Tsuboi; Kenichi Tosaka; Satoshi Kobayashi; Keizo Kato; Futao Kaneko

2008-01-01

40

Purification and characterization of ?-Mannanase from Reinekea sp. KIT-YO10 with transglycosylation activity.  

PubMed

Marine bacterium Reinekea sp. KIT-YO10 was isolated from the seashore of Kanazawa Port in Japan as a seaweed-degrading bacterium. Homology between KIT-YO10 16S rDNA and the 16S rDNA of Reinekea blandensis and Reinekea marinisedimentorum was 96.4 and 95.4%, respectively. Endo-1,4-?-D-mannanase (?-mannanase, EC 3.2.1.78) from Reinekea sp. KIT-YO10 was purified 29.4-fold to a 21% yield using anion exchange chromatography. The purified enzyme had a molecular mass of 44.3 kDa, as estimated by SDS-PAGE. Furthermore, the purified enzyme displayed high specificity for konjac glucomannan, with no secondary agarase and arginase activity detected. Hydrolysis of konjac glucomannan and locust bean gum yielded oligosaccharides, compatible with an endo mode of substrate depolymerization. The purified enzyme possessed transglycosylation activity when mannooligosaccharides (mannotriose or mannotetraose) were used as substrates. Optimal pH and temperature were determined to be 8.0 and 70 °C, respectively. It showed thermostability at temperatures from 20 to 50 °C and alkaline stability up to pH 10.0. The current enzyme was thermostable and thermophile compared to the ?-mannanase of other marine bacteria. PMID:25036974

Hakamada, Yoshihiro; Ohkubo, Yoshitaka; Ohashi, Shinichi

2014-01-01

41

Yo, Hamlet!  

ERIC Educational Resources Information Center

This article presents Alan Sitomer, an English teacher at Lynwood High School, and how he teaches his students classic literature through hip-hop. These at-risk students attend a severely overcrowded, low-performing school in East Los Angeles that's surrounded by what Sitomer describes as "gangs, guns, and drugs." Prostitutes work the streets just…

Whelan, Debra Lau

2007-01-01

42

The Yo-Yo Problem  

NSDL National Science Digital Library

Students will explore linear patterns, write a pattern in symbolic form, and solve linear equations using algebra tiles, symbolic manipulation, and the graphing calculator. This lesson plan includes the objective, overview of the lesson, needed materials, procedures, assessment, extensions and adaptations, tips, resources, ideas for discussion, and the activity sheets and answer key.

Pbs; Math, Pbs T.

2007-12-12

43

Electronic structure and optical properties of CuYO2 nanocrystals  

NASA Astrophysics Data System (ADS)

A unique class of highly stabile, self-saturated and self-charge-compensated delafossite nanocrystals has been identified. The density functional theory (DFT) study of structural and electronic properties of these nano-crystalline CuYO2 will be presented. To have a better estimate of the electronic excitation energies, and consequently the optical gap, time dependent DFT has been employed as well. The goal is to show, first of all, that these unique set of nanocrystals exists, and to study whether the nano-phase can modify the electronic properties for enhanced optical absorption. It has potential application as photocatalysts for H2 production by water splitting.

Huda, Muhammad; Yan, Yanfa; Turner, John A.; Al-Jassim, Mowafak M.

2013-03-01

44

A new delafossite-type compound CuYO2 I. Synthesis and characterization  

Microsoft Academic Search

Single crystals of a new delafossite-type compound CuYO2 were grown from a Cu2O-Y2O3 melt by slow cooling from 1210°C. The crystal is hexagonal, P63\\/mmc, a = 3.5206(1) Å, c = 11.418(1) Å, Z = 2 and Dx = 5.01 g\\/cm3. Although the crystal belongs to the 2H-polytype of the delafossite family, selected peaks showed a large line broadening on the

T. Ishiguro; N. Ishizawa; N. Mizutani; M. Kato

1983-01-01

45

Anti-Yo Associated Paraneoplastic Cerebellar Degeneration in a Man with Large Cell Cancer of the Lung  

PubMed Central

Purkinje cell cytoplasmic antibody type 1 (PCA-1), or anti-Yo, is the most frequently detected autoantibody in paraneoplastic cerebellar degeneration (PCD). The vast majority of cases of anti-Yo PCD, however, occur in females over 60 years old and are associated with gynecologic tumors. Only 10 cases have been reported in males, and only 2 were associated with cancer of the lung. Here we describe the youngest known case of PCA-1 positive PCD in a male, whose lung tumor was undetectable even on FDG-PET. PMID:24167748

Lee, James; Wang, Bonnie H.; Yekkirala, Lalitha

2013-01-01

46

Increasing High School Students' Interest in STEM Education through Collaborative Brainstorming with Yo-Yos  

ERIC Educational Resources Information Center

Brainstorming is a creativity technique in which a group of people (or an individual person) spontaneously generates a set of ideas to find the solution to a particular problem. This paper describes an innovative approach called "brainstorming with yo-yos," which was implemented in an outreach to high school event to increase high school…

Fang, Ning

2013-01-01

47

Stratified Median Housing Prices (quarterly) Houses Mar-11 Dec-10 Sep-10 Mar-10 QoQ % YoY %  

E-print Network

Stratified Median Housing Prices (quarterly) Houses Mar-11 Dec-10 Sep-10 Mar-10 QoQ % Yo.5% National $406,279 $411,422 $409,140 $404,559 -1.2% 0.4% #12;Capital City Results Sydney · House prices fell by -0.7% over the quarter following a flat result in December · Sydney's median house price is now

Peters, Richard

48

The Yo me cuido(®) Program: Addressing Breast Cancer Screening and Prevention Among Hispanic Women.  

PubMed

Breast cancer is less likely to be diagnosed at the earliest stage in Hispanic/Latino (Hispanic) women compared to non-Hispanic White women, even after accounting for differences in age, socioeconomic status, and method of detection. Moffitt Cancer Center created a comprehensive health education program called Yo me cuido (®) (YMC) to address and reduce breast cancer disparities among Spanish- and English-speaking Hispanic women by providing breast cancer and healthy lifestyles awareness and education, and promoting breast cancer screenings, reminders, and referrals for women 40 years and older. The purpose of this paper is to showcase the innovative approaches and methods to cancer prevention and early detection of the YMC program, and to promote it as an effective tool for improving outcomes in community health education, outreach, and engagement activities with Hispanic populations. Key components of the program include educational workshops, mammogram referrals, and a multimedia campaign. The YMC program is unique because of its approaches in reaching the Hispanic population, such as delivering the program with compassionate services to empower participants to live a healthier lifestyle. Additionally, direct follow-up for mammography screenings is provided by program staff. From 2011 to 2013, YMC has educated 2,226 women and 165 men through 93 workshops. About 684 (52 %) women ages 40 and older have had a screening mammogram within their first year of participating in the program. The YMC program is an innovative cancer education and outreach program that has demonstrated a positive impact on the lives of the Hispanic community in the Tampa Bay region. PMID:25099235

Davis, Jenna L; Ramos, Roberto; Rivera-Colón, Venessa; Escobar, Myriam; Palencia, Jeannette; Grant, Cathy G; Green, B Lee

2014-08-01

49

Luminescence Properties of Delafossite-Type CuYO2 Doped with Calcium, Oxygen or Rare Earth Tb  

Microsoft Academic Search

Delafossite-type CuYO2 and CuY1-xCaxO2 (x<= 0.05) samples exhibited a green-PL-emission band due to the Cu+ interconfiguration transition from 3d94s1 to 3d10 at room temperature. With increasing Ca concentration, the Cu+ emission shifted slightly to the shorter-wavelength side with a slightly weaker emission intensity. This slight change in Cu+ emission property is considered to be caused by the increase in hole

Nozomu Tsuboi; Hiroshi Ohara; Takanobu Hoshino; Satoshi Kobayashi; Keizo Kato; Futao Kaneko

2005-01-01

50

Networking.  

ERIC Educational Resources Information Center

Networking is an information giving and receiving system, a support system, and a means whereby women can get ahead in careers--either in new jobs or in current positions. Networking information can create many opportunities: women can talk about how other women handle situations and tasks, and previously established contacts can be used in…

Duvall, Betty

51

Mössbauer investigation of Sr 1- xLa xFe 12- yCo yO 19 ferrites  

NASA Astrophysics Data System (ADS)

Sr 1- xLa xFe 12- yCo yO 19 powders with y/ x=0.75 and x=0.1, 0.2, 0.3, 0.4 were prepared according to a ceramic process. X-ray diffraction analysis shows that all the powders are of single, hexagonal M-type, phase. The Mössbauer investigation confirms that Co 2+ substitutes for Fe 3+ in both 4f 2 (mainly) and 2a sites. The most important hyperfine parameters changes concern the 12k, 4f 2 and 2b sites and are related to both Co 2+/Fe 3+ and La 3+/Sr 2+ substitution effects.

Lechevallier, L.; Le Breton, J. M.; Teillet, J.; Morel, A.; Kools, F.; Tenaud, P.

2003-04-01

52

Electrochemistry and structure of Li 2- xCr yMn 2- yO 4 phases  

NASA Astrophysics Data System (ADS)

The synthesis of phases in the solid state solution series Li 2Cr yMn 2- yO 4 where 0< y<2 and their use as cathodes in lithium ion cells was reported previously [I.J. Davidson, R.S. McMillan, J.J. Murray, J. Power Sources, 54 (1995) 205-208]. This paper reports the results of electrochemical evaluations with metallic lithium anodes and on Rietveld refinements of X-ray and neutron powder diffraction data for these phases. Although these materials are prepared at moderately high temperatures, the refinements show that they have a structure similar to the monoclinic layered form of LiMnO 2 prepared by soft chemistry at low temperatures by Armstrong and Bruce [A.R. Armstrong, P.G. Bruce, Nature, 381 (1996) 499-500] and by Delmas and Capitaine [C. Delmas, F. Capitaine, Extended Abstracts of the Eighth International Meeting on Lithium Batteries (1996) 470-471]. The degree of monoclinic distortion in the initial materials has an effect on the structural changes that occur on charging. The phases with a small monoclinic distortion change to an undistorted hexagonal structure on their first charge while those with a large monoclinic distortion change to a spinel-like structure on cycling.

Davidson, I. J.; McMillan, R. S.; Slegr, H.; Luan, B.; Kargina, I.; Murray, J. J.; Swainson, I. P.

53

UW MEDICINE | MEDICAL INforMAtIoN HoW to rEqUEst A Copy of yoUr  

E-print Network

UW MEDICINE | MEDICAL INforMAtIoN 06.2013 HoW to rEqUEst A Copy of yoUr UW MEDICINE MEDICAL r requested for continuation of care are released at no charge. To Obtain a Copy of your UW Medicine medical 98133 fax: 206.368.1920 phone: 206.368.1616 Hall Health Center Mail: 4060 NE stevens Way Box 354410

Borenstein, Elhanan

54

Optical and spectroscopic properties of human whole blood and plasma with and without Y?O? and Nd³?:Y?O? nanoparticles.  

PubMed

The optical properties of human whole blood and blood plasma with and without Y?O? and Nd³?:Y?O? nanoparticles are characterized in the near infrared region at 808 nm using a double integrating sphere technique. Using experimentally measured quantities of diffuse reflectance and diffuse transmittance, a computational analysis was conducted utilizing the Kubelka-Munk, the Inverse Adding Doubling, and Magic Light Kubelka-Munk and Monte Carlo Methods to determine optical properties of the absorption and scattering coefficients. Room temperature absorption and emission spectra were also acquired of Nd³?:Y?O? nanoparticles elucidating their utility as biological markers. The emission spectra of Nd³?:Y?O? were taken by exciting the nanoparticles before and after entering the whole blood sample. The emission from the ?F(3/2)????I(11/2) manifold transition of Nd³?:Y?O? nanoparticles readily propagates through the blood sample at excitation of 808 nm and exhibits a shift in relative intensities of the peaks due to differences in scattering. At 808 nm, in both whole blood and plasma samples, a direct relationship was found with absorption coefficient and Y?O? nanoparticle concentration. Results for the whole blood indicate a small inverse relationship with Y?O? nanoparticle concentration and scattering coefficient and in contrast a direct relation for the plasma. PMID:23380906

Barrera, Frederick J; Yust, Brian; Mimun, Lawrence C; Nash, Kelly L; Tsin, Andrew T; Sardar, Dhiraj K

2013-11-01

55

Thermodynamic Database for the NdO(1.5)-YO(1.5)-YbO(1.5)-ScO(1.5)-ZrO2 System  

NASA Technical Reports Server (NTRS)

A database for YO(1.5)-NdO(1.5)-YbO(1.5)-ScO(1.5)-ZrO2 for ThermoCalc (ThermoCalc AB, Stockholm, Sweden) has been developed. The basis of this work is the YO(1.5)-ZrO2 assessment by Y. Du, Z. Jin, and P. Huang, 'Thermodynamic Assessment of the ZrO2-YO(1.5) System'. Experimentally only the YO(1.5)-ZrO2 system has been well-studied. All other systems are only approximately known. The major simplification in this work is the treatment of each single cation unit as a component. The pure liquid oxides are taken as reference states and two term lattice stability descriptions are used for each of the components. The limited experimental phase diagrams are reproduced.

Jacobson, Nathan S.; Copland, Evan H.; Kaufman, Larry

2001-01-01

56

Wet precipitate method for mixing magnesium and uranium in preparation of Mg yU 1- yO 2+ x solid solution  

NASA Astrophysics Data System (ADS)

A wet method was studied to mix magnesium and uranium finely for fabricating homogeneous solid solution Mg yU 1- yO 2+ x ( x?0 or x < 0). The method consists of precipitate formation of ammonium diuranate (ADU) from dilute HNO 3 solution containing calculated concentrations of uranyl nitrate, NH 4NO 3 and Mg(NO 3) 2 · 6H 2O. Since a small portion of the solution containing Mg is held in the cream-like precipitate of ADU, subsequent heating after careful drying of the precipitate leads to form homogeneous solid solutions. NH 4NO 3 prevents the solution from precipitating Mg(OH) 2 on ammonia addition. The concentration relation of the chemical species was examined for 10 ml of 0.21 M uranyl nitrate solution in 0.014 M HNO 3. It was found that Mg(OH) 2 did not precipitate with the addition of 2 g NH 4NO 3. The 5 ml addition of 25 wt% ammonia water was sufficient for ADU formation. The concentration of Mg in the solid was proportional to the amount of Mg(NO 3) 2 · 6H 2O under the relevant condition. From the vacuum dried ADU precipitate (method (4)), homogeneous Mg yU 1- yO 2+ x solid solutions were prepared.

Fujino, Takeo; Hoshi, Yoshihide; Sato, Nobuaki; Yamada, Kohta

1999-10-01

57

Synthesis and luminescence properties of Sm3+-doped La2WyMo2-yO9 orange-red phosphors  

NASA Astrophysics Data System (ADS)

La2WyMo2-yO9 phosphors activated with the trivalent rare-earth Sm3+ were synthesized via a traditional solid-state reaction, their structure and luminescence properties were investigated by using X-ray diffractometer and fluorescence spectrophotometer. There were three emission peaks centered at 563, 599, and 646 nm corresponding to the 4G5/2?6H5/2, 4G5/2?6H7/2, 4G5/2?6H9/2 transitions of Sm3+ under the 402 nm ultraviolet excitation. Investigation on Sm3+ concentration-dependent emission spectra indicated that La1.97WMoO9:3% Sm3+ phosphor exhibited the strongest orange-red emission with a CIE value of (0.5425, 0.4541). Therefore, it is considered to be a new promising orange-red emitting phosphor for white light emitting diode (LED) application.

Deng, Yaomin; Yi, Shuangping; Huang, Jun; Zhao, Weiren; Xian, Jieqiang

2014-01-01

58

Intrinsic Josephson properties in Pb1-ySr2Y1-xCaxCu2+yO7+? epitaxial films  

NASA Astrophysics Data System (ADS)

We report the first observation of intrinsic Josephson junction (IJJ) characteristics in the Pb1-ySr2Y1-xCaxCu2+yO7+? (Pb1212) epitaxial film. Pb1212 epitaxial film has been grown on SrTiO3 (100) substrates by a two-step growth technique. A small mesa structure (S = 4?m2) has been fabricated on a film surface using a standard photolithography and an Ar ion milling technique. The superconducting transition temperature of the IJJ is 43 K. At 4.2 K, the value of Jc (the critical current density) is 2.2 kA/cm2. The depth of the hysteresis defined as ? = (Jc+Jr)/ Jc is 0.89, where Jr is the return current density. The temperature dependence of Jc shows good agreement with Ambegaokar-Baratoff theory.

Komori, Sachio; Kakeya, Itsuhiro

2014-12-01

59

Thermal stability and oxidation resistance of TiCrAlYO coatings on SS430 for solid oxide fuel cell interconnect applications  

SciTech Connect

Chromia-forming ferritic stainless steels are being considered for interconnects applications in planar solid oxide fuel cell (SOFC) stacks because of their low cost and physical properties. At high temperatures, ferritic steels lack environmental stability in the SOFC operating environment, and gradually degrade the cell performance. In this study, an effective, dense and well adherent TiCrAlYO coating was deposited on an SS430 alloy using the filtered arc deposition technique. High-energy ion backscattering was used to characterize the composition and the thermal stability of the coatings. The chromium volatility of the coated steel plates at 800 oC was also measured using ion beam analysis. Significant reductions in oxidation rates as well as reduced Cr volatility were observed for the coated alloys.

Chen, Hui; Lucas, J. A.; Priyantha, Weerasinghe A.; Kopczyk, M.; Smith, Richard J.; Lund, Kasey R.; Key, Camas; Finsterbusch, M.; Gannon, Paul E.; Deibert, Max; Gorokhovsky, Vladimir I.; Shutthanandan, V.; Nachimuthu, Ponnusamy

2008-06-25

60

Phase evaluation and optical studies of cubic MnxZr1-xO2 and CoyZr1-yO2 nanocrystals  

NASA Astrophysics Data System (ADS)

Nanocrystallites of cubic phase MnxZr1-xO2(0?x?0.25) and CoyZr1-yO2(0?y?0.20) have been synthesized by co-precipitation technique. The role of dopant concentration and the heat-treatment conditions on the cubic phase stability, crystallite size and optical behavior of these compounds have been discussed. Analysis of the structural data reveals that the cubic-phase is stable up to a critical dopant concentration xc ? 0.25 and yc ? 0.20 beyond which monoclinic phase of ZrO2 emerges. The diffuse-reflectance-spectroscopy of MnxZr1-xO2 exhibits a strong absorption peak at ? = 365 nm associated with ligand to metal charge-transfer transition 3P2(O)?1S0(Zr) representing the energy band-gap (Eg = 3.39 eV). In addition, a series of absorption bands are observed at 520, 654, and 712 nm associated with the crystal-field transitions of Mn4+ i.e. from 4A2g(F) state to 4T2g(F), 4T1g(P) and 2E states, respectively. However, in CoyZr1-yO2, the main absorption is centered at 211 nm due to the electronic transitions from valance band O2p to conduction band Zr4d together with inter-valence charge transfer transitions occurring at 242, 270, 358 and 757 nm.

Thota, S.; Ansari, A.; Singh, S. K.; Mallick, A.; Kumar, J.

2013-06-01

61

SPECTRAL FILTERING FOR PLANT PRODUCTION http://ncr101.montana.edu/Light1994Conf/7_1_Young/Yo... 1 of 13 12/20/06 9:34 AM  

E-print Network

SPECTRAL FILTERING FOR PLANT PRODUCTION http://ncr101.montana.edu/Light1994Conf/7_1_Young/Yo... 1) 1994 NASA-CP-95-3309 home | contents SPECTRAL FILTERING FOR PLANT PRODUCTION Roy E. Young, Margaret J. McMahon, Nihal C. Rajapakse and Dennis R. Decoteau RADIATION AND PLANTS In the scheme of living

Decoteau, Dennis R.

62

Network Management Network Management  

E-print Network

"From Networks and Network Management into Services and Service Management". J. of Network ans System · Operation deals with keeping the network up (and the service provided by the network) · Administration ­ Network management ­ System management ­ Application management ­ Service management Network Management

63

Effect of Mg doping on the local structure of LiMgyCo1-yO2 cathode material investigated by X-ray absorption spectroscopy  

NASA Astrophysics Data System (ADS)

A higher capacity and better cyclability are apparent when magnesium is introduced into the structure of LiCoO2 (y = 0.15). XRD analysis of LiMgyCo1-yO2 (y = 0, 0.1, 0.15), synthesized at 800 °C using a microwave assisted method, shows that the material is in the R-3m space group and to have a slightly expanded unit cell that increases with greater magnesium doping. Structural analysis by X-ray absorption spectroscopy (XAS) at the Co K-edge, L-edge and O K-edge shows that the magnesium is located in the transition metal layer rather than in the lithium layer and the charge balance results from the formation of oxygen vacancies rather than Co4+, while cobalt remains in the 3+ oxidation state. Interestingly, oxygen is found to participate in the charge compensation. Both magnesium, in the transition metal layer, and the Co-defect structure are attributed to the contribution towards structural stabilization of LiCoO2, thereby resulting in its enhanced electrochemical performance.

Cheng, J. H.; Pan, C. J.; Nithya, C.; Thirunakaran, R.; Gopukumar, S.; Chen, C. H.; Lee, J. F.; Chen, J. M.; Sivashanmugam, A.; Hwang, B. J.

2014-04-01

64

Electrical and magnetic properties of nanosized Mg0.2Mn0.5Ni0.3AlyFe2-yO4 ferrites  

NASA Astrophysics Data System (ADS)

Electrical and magnetic behavior of Mg0.2Mn0.5Ni0.3AlyFe2-yO4(y=0.0-0.3) spinel ferrites synthesized by citrate precursor method sintered at 1200°C are reported. Samples were characterized by X-ray diffraction technique at room temperature. Lattice parameter `a', saturation magnetization Ms, retentivity Mr, Bohr magneton nB and remnant ratio R=Mr/Ms are seen to decrease whereas coercivity Hc shows increasing trend with increasing Al3+ content. Anisotropy field HKA increases with aluminium content, which along with Ms enable calculation of magneto-crystalline anisotopy constant K1, which increases with increasing Al3+ content. The compositional variations of hysteresis parameters like Ms, Hc, Mr and R reveals that grains in composition studied are of multidomain type. A significant reduction in value of initial permeability and relative loss factor (RLF) was observed with increase of Al3+ ions. DC electrical resistivity decreases with increase in temperature exhibiting semiconductor like behavior. Activation energy is determined from dc electrical resistivity measurements. High dc resistivity and very low RLF makes these ferrites suitable particularly for high-frequency applications where eddy current losses are required to be low.

Verma, Satish; Chand, Jagdish; Kumar, Pawan; Singh, M.

2012-06-01

65

Role of Strong Electronic Correlations in the Metal-To-Insulator Transition in Disordered LiAlyTi2-yO4  

NASA Astrophysics Data System (ADS)

The compound LiAlyTi2-yO4 undergoes a metal-to-insulator transition for yc˜0.33. It is known that disorder alone is insufficient to explain this transition; e.g., a quantum site percolation model predicts yc˜0.8. We have included (Hubbard) electronic interactions into a model of this compound, using a real-space Hartree-Fock approach that achieves self-consistency at every site, and have found that for a Hubbard energy equal to 1.5 times the non-interacting bandwidth one obtains yc˜0.3. Further, with increasing Hubbard energy we find an Altshuler-Aronov suppression of the density of states, ?N(?)˜|?-?F|, that reduces the density of states at the Fermi energy to zero at the critical Hubbard interaction. Using this ratio of correlation to hopping energy one is led to a prediction of the near-neighbor superexchange (J/ ttilde 1/3) which is similar to that for the cuprate superconductors.

Fazileh, F.; Gooding, R. J.; Atkinson, W. A.; Johnston, D. C.

2006-02-01

66

Role of magnetic moments in the metal-to-insulator transition in LiAlyTi2-yO4  

NASA Astrophysics Data System (ADS)

While the high-Tc cuprate problem remains an active field of research, several parallel studies in potentially related physical systems have been undertaken. For example, LiTi2O4, known to have a superconducting Tc of about 13K, has been suggested to have a strong relation to the cuprates. Our studies are addressing the key question: Are strong electronic correlations found in LiTi2O4? To answer this we have focussed on a study of the metal-to-insulator transition that LiAlyTi2-yO4 is found to undergo for y~ 0.3, and have modelled this material using a quantum-site percolation model that includeselectronic correlations through an on-site repulsive Hubbard interaction. We find that in sucha model this transition is reproduced through the appearance of an Altshuler-Aronov-like suppression of the density of states at the Fermi level, called by some a pseudogap, when an intermediate-strength Hubbard interaction is introduced. Here we focus on results displaying the essential role that magnetic moments that develop on the Ti sites seem to play in producing this transition, physics absent from the original Altshuler-Aronov analysis.

Fazileh, F.; Chen, X.; Gooding, R. J.; Atkinson, W. A.; Johnston, D. C.

2009-02-01

67

Control of luminescence and conductivity of delafossite-type CuYO 2 by substitution of rare earth cation (Eu, Tb) and\\/or Ca cation for Y cation  

Microsoft Academic Search

Delafossite-type oxides of CuTbyY1?yO2, CuEuyY1?yO2, CuCaxTbyY1?x?yO2 and CuCaxEuyY1?x?yO2 have been prepared by solid state reactions. The lattice-parameter dependence on the composition implies substitution of the Tb3+, Eu3+ and Ca2+ cations for the Y3+ site. Noticeable sharp emission lines due to the f–f transitions (5D4?7FJ, J=3–6) of Tb3+ or due to the f–f transitions (5D0?7FJ, J=0–4) of Eu3+ are observed at

Nozomu Tsuboi; Takanobu Hoshino; Hiroshi Ohara; Tomonori Suzuki; Satoshi Kobayashi; Keizo Kato; Futao Kaneko

2005-01-01

68

Network Management Network Management  

E-print Network

, operational and QOS requirements...... ­ From:Saydam, Magendaz "From Networks and Network Management into Services and Service Management". J. of Network ans System Management #12;Network Management Pag. 3 Network · Provisioning means resource configuration to enable a given service Network management and QoS provisioning - 5

69

Structure, band gap, and Mn-related mid-gap states in epitaxial single crystal (Zn{sub 1-x}Mg{sub x}){sub 1-y}Mn{sub y}O thin films  

SciTech Connect

Epitaxial (Zn{sub 1-x}Mg{sub x}){sub 1-y}Mn{sub y}O thin films were grown on c-Al{sub 2}O{sub 3} substrates by radio frequency oxygen plasma assisted molecular beam epitaxy. Single crystal structure of the (Zn{sub 1-x}Mg{sub x}){sub 1-y}Mn{sub y}O films was revealed by reflection high energy electron diffraction and X-ray diffraction. The band gap of the films can be tuned dramatically with increasing the Mg concentration, while the onset energy of Mn-related mid-gap absorption band only shows a small blue shift. Photoconductivity measurements indicate the Mn-related mid-gap states in (Zn{sub 1-x}Mg{sub x}){sub 1-y}Mn{sub y}O films can create free carriers and contribute to charge transfer transitions. The conduction band offset {Delta}E{sub C} = 0.13 eV and valence band offset {Delta}E{sub V} = 0.1 eV were obtained for ZnO/Zn{sub 0.8}Mg{sub 0.2}O heterostructures, which increase to {Delta}E{sub C} = 0.21 eV and {Delta}E{sub V} = 0.14 eV for ZnO/Zn{sub 0.7}Mg{sub 0.3}O heterostructures.

Zhu Dapeng; Liu Guolei; Xiao Shuqin; Yan Shishen; He Shumin; Cai Li; Li Qinghao; Hu Shujun; Chen Yanxue; Kang Shishou; Mei Liangmo [School of Physics, National Key Laboratory of Crystal Materials, Shandong University, Jinan, Shandong 250100 (China); Cao Qiang [School of Physics, National Key Laboratory of Crystal Materials, Shandong University, Jinan, Shandong 250100 (China); Department of Physics, Qufu Normal University, Qufu, Shandong 273165 (China)

2013-05-07

70

Photoelectrical properties of sprayed In2-2xAl2xS3- 3yO3y alloys  

NASA Astrophysics Data System (ADS)

In2-2xAl2xS3-3yO3y alloys have been prepared on Pyrextrademark glass substrates by the spray pyrolysis technique. The shape of the photoconductivity spectrums Iph (hnu) and the variations Iph (f ) and Iph (V) allow us to understand the conduction mechanism and the photocarriers' recombination. For low compositions (xless-than-or-equal0.2), Iph)(V parabolic variation shows that this conduction is limited by the space charge zone in accordance with Child's law (Iph[is proportional to]V2) [N. F. Mott and R. W. Gurney, Electronics Processes in Ionic Crystals (Oxford, New York, 1940), p. 463]. The exploitation of such variation shows that the density of the trap centers increases with the composition. For x[greater-than-or-equal, slanted]0.4, the electrical conduction instead follows Ohm's law. In the same way, the analysis of an extension of Devore's model [Phys. Rev. 102, 86 (1956)] as (Iph)hnu2 versus photon energy hnu shows an increase of the band gap energy Eg according to a parabolic profile. On the other hand, for low compositions (x=0,0.05,0.1,0.2), the conductivity study as a function of the temperature presents a deviation to Arrhenius's law in the intermediate temperature domain ranging from 80 to 330 K. Moreover, in this domain, the study of the activation energy Ea)(T according to Werner's model [Solid State Phenom. 37, 214 (1994)] supposing potential fluctuations at the grain boundaries yields the values of the barrier high phib and the standard deviation sigma][phi. From these results, we see that Eg increased versus x and that the electrical properties are essentially preserved for low aluminum concentration films. This may be due to a minor presence of an Al2O3 phase for such deposits.

Bhira, L.; Belgacem, S.; Bernede, J. C.

2002-11-01

71

Como Lo Hago Yo: Myelomeningocele  

PubMed Central

Fortificación con ádico fólico es efectiva, pero aún falta conciencia en los jóvenes. La legalidad del aborto aumenta la importancia de la consulta prenatal. Realizo la cirugía bajo microcoscopio por razones didácticas. Irrigación continua para reducir la temperatura del tejido. Trato a la plaqueta como tejido viable. No suturo la plaqueta. No cierro músculo. ATB por una semana después de cirugía. Hidrocefalia: Válvula en todos los casos de ventriculomegalia. Médula anclada: Desanclar una sola vez. Chiari II: Revisar la válvula. Incluir en el seguimiento rendimiento escolar, puede indicar obstrucción de la válvula o médula anclada. PMID:24791217

Lazareff, Jorge

2014-01-01

72

Microstructure of Cu- and Y-rich YBa sub 2 Cu sub 3 O sub 7 minus x thin films: Identification of the CuYO sub 2 phase  

SciTech Connect

The CuYO{sub 2} delafossite-type structure has been identified as a second phase in thin films of Cu- and Y-rich YBa{sub 2}Cu{sub 3}O{sub 7{minus}{ital x}} (123) made by electron beam co-evaporation at conditions of low oxygen pressure; this phase occurs as extremely small, densely distributed, highly oriented precipitates within the 123 matrix. The smallest (sub-100 A) (00.1) oriented precipitates of this hexagonal phase are strained to give a better lattice match to the surrounding 123 structure. The results suggest that, for thin film deposition conditions of sufficiently low temperature and pressure, there may be a tie line between YBa{sub 2}Cu{sub 3}O{sub 7{minus}{ital x}} and CuYO{sub 2} in the equilibrium phase diagram. The size and distribution of the precipitates is such as would be expected to influence structurally sensitive superconducting transport properties.

Marshall, A.F.; Matijasevic, V.; Rosenthal, P.; Shinohara, K.; Hammond, R.H.; Beasley, M.R. (Stanford University, Stanford, CA (USA). Center for Materials Research Stanford University, Stanford, CA (USA). Department of Applied Physics)

1990-09-10

73

Examining the metal-to-insulator transitions in Li1+xTi2-xO4 and LiAlyTi2-yO4 with a quantum site percolation model  

NASA Astrophysics Data System (ADS)

We have studied the composition-induced metal-to-insulator transitions (MIT) of cation substituted lithium titanate, in the forms Li1+xTi2-xO4 and LiAlyTi2-yO4, utilizing a quantum site percolation model; we argue that such a model provides a very reliable representation of the noninteracting electrons in this material if strong correlations are ignored. We then determine whether or not such a model of 3d1 electrons moving on the Ti (corner-sharing tetrahedral) sublattice describes the observed MIT’s, with the critical concentration defined by the matching of the mobility edge and the chemical potential. Our analysis leads to quantitative predictions that are in disagreement with those measured experimentally. For example, experimentally for the LiAlyTi2-yO4 compound an Al concentration of yc?0.33 produces a metal-to-insulator transition, whereas our analysis of a quantum site percolation model predicts yc?0.83. One hypothesis that is consistent with these results is that since strong correlations are ignored in our quantum site percolation model, which includes the effects of configurational disorder only, such strong electronic correlations are both present and important.

Fazileh, F.; Gooding, R. J.; Johnston, D. C.

2004-03-01

74

istockphoto.com/tA2Yo4NoRi Digital Object Identifier 10.1109/MSP.2014.2329196  

E-print Network

], detect cliques in social networks [6], and analyze fluo- rescence spectroscopy data [7], to name a few article combines a tutorial on state-of-the-art ten- sor decomposition as it relates to big data analytics, especially for analyzing big data, and tensors easily turn really big, e.g., , , ,1 000 1 000 1 000 1

Sidiropoulos, Nikolaos D.

75

Introduction to k'yu ts'udalaas aa  

E-print Network

word for shell. Therefore, bivalve means that this organism has 2 shells, so is more similar to a clam than a worm. ­ A clam uses its shells for shelter, but the shipworm uses wood for shelter so its shells are much smaller than clam shells. ·There are over 100 different species of shipworms. ·These unique

76

Phase diagram calculations of ZrO 2 -based ceramics with an emphasis on the reduction\\/oxidation equilibria of cerium ions in the ZrO 2 YO 1.5 CeO 2 CeO 1.5 system  

Microsoft Academic Search

Phase diagram calculations that were made previously for the ZrO2-MO\\u000a m\\/2 (m = 2, 3, 4) systems and for the ZrO2-YO1.5-MO\\u000a m\\/2 (M = transition metals) systems have been extended to the ZrO2-YO1.5-CeO2(-CeO1.5) system to make an attempt to explain (1) thermogravimetric (TG) results as a function of oxygen potential, (2) electronic\\u000a conductivity as a function of oxygen potential, and

Harumi Yokokawa; Natsuko Sakai; Teruhisa Horita; Katsuhiko Yamaji; Yueping Xiong; Takanori Otake; Hiroo Yugami; Tatsuya Kawada; Junichiro Mizusaki

2001-01-01

77

Synthesis and investigation of magnetic properties of substituted ferrite nanoparticles of spinel system Mn 1-xZn x[Fe 2-yL y]O 4  

NASA Astrophysics Data System (ADS)

Superparamagnetic nanoparticles of the spinel ferrite four-element system Mn 1-xZn x[Fe 2-yL y]O 4 (where L:Gd 3+, La 3+, Ce 3+, Eu 3+, Dy 3+, Er 3+,Yb 3+) were synthesized by the co-precipitation method. The magnetic moments of the 10 nm diameter nanoparticles were comparable to the ones of Fe 3O 4 nanoparticles. A comparatively low TC (˜52-72 °C) was observed for some of the compositions. The heating mechanism of the superparamagnetic particles in the AC magnetic field at radiofrequency range is discussed and especially the absence of the hysteresis loop in the M-H curve at room temperature. One possible explanation—spontaneous particle agglomeration—was experimentally verified.

Brusentsova, Tatiana N.; Kuznetsov, Viatcheslav D.

2007-04-01

78

Network Cosmology  

NASA Astrophysics Data System (ADS)

Prediction and control of the dynamics of complex networks is a central problem in network science. Structural and dynamical similarities of different real networks suggest that some universal laws might accurately describe the dynamics of these networks, albeit the nature and common origin of such laws remain elusive. Here we show that the causal network representing the large-scale structure of spacetime in our accelerating universe is a power-law graph with strong clustering, similar to many complex networks such as the Internet, social, or biological networks. We prove that this structural similarity is a consequence of the asymptotic equivalence between the large-scale growth dynamics of complex networks and causal networks. This equivalence suggests that unexpectedly similar laws govern the dynamics of complex networks and spacetime in the universe, with implications to network science and cosmology.

Krioukov, Dmitri; Kitsak, Maksim; Sinkovits, Robert S.; Rideout, David; Meyer, David; Boguñá, Marián

2012-11-01

79

Network Cosmology  

PubMed Central

Prediction and control of the dynamics of complex networks is a central problem in network science. Structural and dynamical similarities of different real networks suggest that some universal laws might accurately describe the dynamics of these networks, albeit the nature and common origin of such laws remain elusive. Here we show that the causal network representing the large-scale structure of spacetime in our accelerating universe is a power-law graph with strong clustering, similar to many complex networks such as the Internet, social, or biological networks. We prove that this structural similarity is a consequence of the asymptotic equivalence between the large-scale growth dynamics of complex networks and causal networks. This equivalence suggests that unexpectedly similar laws govern the dynamics of complex networks and spacetime in the universe, with implications to network science and cosmology. PMID:23162688

Krioukov, Dmitri; Kitsak, Maksim; Sinkovits, Robert S.; Rideout, David; Meyer, David; Boguñá, Marián

2012-01-01

80

H+ diffusion and electrochemical stability of Li1+x+yAlxTi2-xSiyP3-yO12 glass in aqueous Li/air battery electrolytes  

SciTech Connect

It is well known that LATP (Li1+x+y AlxTi2?x SiyP3?yO12) glass is a good lithium ion conductor. However, the interaction between LATP glass and H+ ions (including its diffusion and surface adsorption) needs to be well understood before the long-term application of LATP glass in an aqueous electrolyte based Li-air batteries where H+ always present. In this work, we investigate the H+ ion diffusion properties in LATP glass and their surface interactions using both experimental and modeling approaches. Our analysis indicates that the apparent H+ related current observed in the initial cyclic voltammetry scan should be attributed to the adsorption of H+ ions on the LATP glass rather than the bulk diffusion of H+ ions in the glass. Furthermore, the density functional theory calculations indicate that the H+ ion diffusion energy barrier (3.21 eV) is much higher than that of Li+ ion (0.79 eV) and Na+ ion (0.79 eV) in NASICON type LiTi2(PO4)3 material. As a result, the H+ ion conductivity in LATP glass is negligible at room temperature. However, significant surface corrosion was found after the LATP glass was soaked in strong alkaline electrolyte for extended time. Therefore, appropriate electrolytes have to be developed to prevent the corrosion of LATP glass before its practical application for Li-air batteries using aqueous electrolyte.

Ding, Fei; Xu, Wu; Shao, Yuyan; Chen, Xilin; Wang, Zhiguo; Gao, Fei; Liu, Xingjiang; Zhang, Jiguang

2012-09-15

81

Relaxor single crystals in the (Bi1/2Na1/2)1-xBaxZryTi1-yO3 system exhibiting high electrostrictive strain  

NASA Astrophysics Data System (ADS)

Single crystals have been grown in the (Bi1/2Na1/2)1-xBaxZryTi1-yO3 perovskite system by a self-flux method over the range of compositions y=0.04 and x=0.06-0.012. Rhombohedral (x?0.08) and tetragonal phase (x?0.09) crystals have been obtained that do not show polarization or field-induced strain hysteresis characteristics of a ferroelectric. However, a frequency-dispersive dielectric response characteristic of a relaxor ferroelectric, and predominantly electrostrictive actuation, is observed across the range of compositions tested, with Q11=(2.8-3.3)×10-2m4/C2. Due to induced polarizations that do not saturate at fields beyond 50 kV/cm, high electrostrictive strains are obtained. Rhombohedral phase crystals exhibit d33 up to 1180 pC/N and strains of S3=0.3% before electrical breakdown, while tetragonal phase crystals exhibit d33 up to 2000 pC/N and S3 up to 0.45% strain. These crystals show the highest electrostrictive strains yet reported for an inorganic compound. The unusually high electrostriction is discussed in relation to an energy landscape that allows ferroelastic and ferroelectric distortions to be simultaneously accessible at the nanometer scale.

Sheets, Sossity A.; Soukhojak, Andrey N.; Ohashi, Naoki; Chiang, Yet-Ming

2001-11-01

82

Network Solutions.  

ERIC Educational Resources Information Center

This special section explains the latest developments in networking technologies, profiles school districts benefiting from successful implementations, and reviews new products for building networks. Highlights include ATM (asynchronous transfer mode), cable modems, networking switches, Internet screening software, file servers, network management…

Vietzke, Robert; And Others

1996-01-01

83

Networking standards  

NASA Technical Reports Server (NTRS)

The enterprise network is currently a multivendor environment consisting of many defacto and proprietary standards. During the 1990s, these networks will evolve towards networks which are based on international standards in both Local Area Network (LAN) and Wide Area Network (WAN) space. Also, you can expect to see the higher level functions and applications begin the same transition. Additional information is given in viewgraph form.

Davies, Mark

1991-01-01

84

Semantic Networks and Social Networks  

ERIC Educational Resources Information Center

Purpose: To illustrate the need for social network metadata within semantic metadata. Design/methodology/approach: Surveys properties of social networks and the semantic web, suggests that social network analysis applies to semantic content, argues that semantic content is more searchable if social network metadata is merged with semantic web…

Downes, Stephen

2005-01-01

85

ANe wApproac ht oMeasur eSingle-Event Relate dBrai nActivit yUsin gReal-Tim efMRI: Feasibilit yo fSensory ,Motor ,an dHigher Cognitiv eTasks  

Microsoft Academic Search

Real-tim efMR Ii sa rapidl yemergin gmethodolog ytha tenable smonitorin gchange si nbrain activit ydurin ga nongoin gexperiment .I nthi sarticl ew edemonstrat eth efeasibilit yo fperforming single-even tsensory ,motor ,an dhighe rcognitiv etask si nreal-tim eo na clinica lwhole-bod yscanner .This approac hrequire ssensitivit yoptimize dfMR Imethods :Usin gstatistica lparametri cmappin gw equan- tifie dth espatia lexten to fBOL

Valeri jKiselev

86

Efficient network camouflaging in wireless networks  

E-print Network

when protected networks are wireless networks, such as sensor networks and mobile ad hoc networks. The reason is that wireless networks are typically subject to resource constraints (e.g. bandwidth, power supply) and possess some unique characteristics...

Jiang, Shu

2006-04-12

87

Computer Networks  

NSDL National Science Digital Library

CSC 344. Computer Networks (3) Prerequisite: CSC 242. The theory and application of inter-computer communication. Local-area and wide-area networks; data transmission and error correction; OSI and TCP/IP layering protocols; ethernet, token ring, token bus and other network technologies; network topologies; the client-server model; bridges and multi-protocol routers; the Internet. Applications include electronic funds transfer and distributed databases.

Hudson, Mr T.

2003-04-21

88

Integrated Networks.  

ERIC Educational Resources Information Center

A strategy for integrated data and voice networks implemented at the University of Michigan is described. These networks often use multi-technologies, multi-vendors, and multi-transmission media that will be fused into a single integrated network. Transmission media include twisted-pair wire, coaxial cable, fiber optics, and microwave. (Author/MLW)

Robinovitz, Stewart

1987-01-01

89

On Networking.  

ERIC Educational Resources Information Center

This paper focuses on the theoretical and practical problems inherent in trying to build, create, develop, enhance, or strengthen networks among persons, groups, or organizations that would be useful in educational change efforts. The concepts of "social networks" and "networking" are defined, and background variables that might influence the…

Miles, Matthew B.

90

Communicative networks  

Microsoft Academic Search

This essay introduces the concept of communicative networks by analyzing Jacob A. Riis's journalistic attempts to solve social problems in New York's slums at the turn of last century. This renowned social reformer not only believed in the mobilizing potential of various networks for public transportation, but also established networks of his own through his books and newspaper articles, which

Peter Bro

2004-01-01

91

Como Lo Hago Yo: Lipomas Medulares  

PubMed Central

Basados en la experiencia de 82 casos; en 5% se observaron anomalías pélvicas asociadas. En los menores de 3 años el motivo de consulta (85%) fue la tumoración. En los mayores de 3 años (42%) tenía problemas neurológicos. Solo el 24% preocupados por la tumoración. El objetivo de la cirugía es desanclar la médula y no remover la totalidad del lipoma. El lipoma de filum es el que es mas simple para operar. Aún cuando la escuela francesa propone operar solamente cuando hay síntomas favorezco cirugía preventiva. Favorezco una segunda cirugía si hay signos de anclaje postoperatorio, aún cuando observamos empeoramiento postoperatorio motor en 2.5% de los operados y urológico a largo plazo en 6% de los operados. PMID:24791218

Portillo, Santiago

2014-01-01

92

our answers t scuss with yo  

E-print Network

betwe B ge you stopp yes, what ty ow long have C bnormal Pap S bnormal Ute acterial Vagi hlamydia? bleed? (Ex. mild m een periods? ped having p pe? _______ e you been u Smear rine Bleedin inosis / Vagi Gonorrhea Hepatitis B Herpes Human Pap Incontinenc ___________ Harborview Medi Northwest Hospit Seattle

Borenstein, Elhanan

93

Sensor networks for social networks  

E-print Network

This thesis outlines the development of software that makes use of Bayesian belief networks and signal processing techniques to make meaningful inferences about real-world phenomena using data obtained from sensor networks. ...

Farry, Michael P. (Michael Patrick)

2006-01-01

94

Spatial networks  

NASA Astrophysics Data System (ADS)

Complex systems are very often organized under the form of networks where nodes and edges are embedded in space. Transportation and mobility networks, Internet, mobile phone networks, power grids, social and contact networks, and neural networks, are all examples where space is relevant and where topology alone does not contain all the information. Characterizing and understanding the structure and the evolution of spatial networks is thus crucial for many different fields, ranging from urbanism to epidemiology. An important consequence of space on networks is that there is a cost associated with the length of edges which in turn has dramatic effects on the topological structure of these networks. We will thoroughly explain the current state of our understanding of how the spatial constraints affect the structure and properties of these networks. We will review the most recent empirical observations and the most important models of spatial networks. We will also discuss various processes which take place on these spatial networks, such as phase transitions, random walks, synchronization, navigation, resilience, and disease spread.

Barthélemy, Marc

2011-02-01

95

Network morphospace.  

PubMed

The structure of complex networks has attracted much attention in recent years. It has been noted that many real-world examples of networked systems share a set of common architectural features. This raises important questions about their origin, for example whether such network attributes reflect common design principles or constraints imposed by selectional forces that have shaped the evolution of network topology. Is it possible to place the many patterns and forms of complex networks into a common space that reveals their relations, and what are the main rules and driving forces that determine which positions in such a space are occupied by systems that have actually evolved? We suggest that these questions can be addressed by combining concepts from two currently relatively unconnected fields. One is theoretical morphology, which has conceptualized the relations between morphological traits defined by mathematical models of biological form. The second is network science, which provides numerous quantitative tools to measure and classify different patterns of local and global network architecture across disparate types of systems. Here, we explore a new theoretical concept that lies at the intersection between both fields, the 'network morphospace'. Defined by axes that represent specific network traits, each point within such a space represents a location occupied by networks that share a set of common 'morphological' characteristics related to aspects of their connectivity. Mapping a network morphospace reveals the extent to which the space is filled by existing networks, thus allowing a distinction between actual and impossible designs and highlighting the generative potential of rules and constraints that pervade the evolution of complex systems. PMID:25540237

Avena-Koenigsberger, Andrea; Goñi, Joaquín; Solé, Ricard; Sporns, Olaf

2015-02-01

96

Network morphospace  

PubMed Central

The structure of complex networks has attracted much attention in recent years. It has been noted that many real-world examples of networked systems share a set of common architectural features. This raises important questions about their origin, for example whether such network attributes reflect common design principles or constraints imposed by selectional forces that have shaped the evolution of network topology. Is it possible to place the many patterns and forms of complex networks into a common space that reveals their relations, and what are the main rules and driving forces that determine which positions in such a space are occupied by systems that have actually evolved? We suggest that these questions can be addressed by combining concepts from two currently relatively unconnected fields. One is theoretical morphology, which has conceptualized the relations between morphological traits defined by mathematical models of biological form. The second is network science, which provides numerous quantitative tools to measure and classify different patterns of local and global network architecture across disparate types of systems. Here, we explore a new theoretical concept that lies at the intersection between both fields, the ‘network morphospace’. Defined by axes that represent specific network traits, each point within such a space represents a location occupied by networks that share a set of common ‘morphological’ characteristics related to aspects of their connectivity. Mapping a network morphospace reveals the extent to which the space is filled by existing networks, thus allowing a distinction between actual and impossible designs and highlighting the generative potential of rules and constraints that pervade the evolution of complex systems. PMID:25540237

Avena-Koenigsberger, Andrea; Goñi, Joaquín; Solé, Ricard; Sporns, Olaf

2015-01-01

97

Network Security  

NSDL National Science Digital Library

This course on Network Security is provided by the Cyber Security Education Consortium (CSEC). The course requires students to perform laboratory assignments in securing networks and operating systems to learn about "network communications from a security standpoint" and "hardware and software security solutions." Links are provided to learn more about the Major Topics Covered, Course Learning Objectives, and Course Outline. The Course Outline includes a list of careers that require the knowledge from this course and related textbooks.

98

Innovation Networks  

NASA Astrophysics Data System (ADS)

The idea for this book started when we organized a topical workshop entitled "Innovation Networks - New Approaches in Modeling and Analyzing" (held in Augsburg, Germany in October 2005), under the auspices of Exystence, a network of excellence funded in the European Union's Fifth Framework Program. Unlike other conferences on innovation and networks, however, this workshop brought together scientists from economics, sociology, communication science, science and technology studies, and physics. With this book we aim to build further on a bridge connecting the bodies of knowledge on networks in economics, the social sciences and, more recently, statistical physics.

Pyka, Andreas; Scharnhorst, Andrea

99

Network reliability  

NASA Technical Reports Server (NTRS)

Network control (or network management) functions are essential for efficient and reliable operation of a network. Some control functions are currently included as part of the Open System Interconnection model. For local area networks, it is widely recognized that there is a need for additional control functions, including fault isolation functions, monitoring functions, and configuration functions. These functions can be implemented in either a central or distributed manner. The Fiber Distributed Data Interface Medium Access Control and Station Management protocols provide an example of distributed implementation. Relative information is presented here in outline form.

Johnson, Marjory J.

1985-01-01

100

Network mobilizer  

Microsoft Academic Search

Purpose – The aim of this paper is to identify how companies mobilize other companies in their surrounding network to work within the plans they develop. Design\\/methodology\\/approach – A conceptual model is developed and its applicability is illustrated by a case study involving a manufacturer-retailer network within Europe. Findings – The study identifies five different challenges that managers need to

Stefanos Mouzas; Pete Naudé

2007-01-01

101

Local networks  

Microsoft Academic Search

The rapidly evolving field of local network technology hasproduced a steady stream of local network products in recent years.The IEEE 802 standards that are now taking shape, because of theircomplexity, do little to narrow the range of alternative technicalapproaches and at the same time encourage more vendors into thefield. The purpose of this paper is to present a systematic,organized overview

William Stallings

1984-01-01

102

Temporal networks  

NASA Astrophysics Data System (ADS)

A great variety of systems in nature, society and technology-from the web of sexual contacts to the Internet, from the nervous system to power grids-can be modeled as graphs of vertices coupled by edges. The network structure, describing how the graph is wired, helps us understand, predict and optimize the behavior of dynamical systems. In many cases, however, the edges are not continuously active. As an example, in networks of communication via e-mail, text messages, or phone calls, edges represent sequences of instantaneous or practically instantaneous contacts. In some cases, edges are active for non-negligible periods of time: e.g., the proximity patterns of inpatients at hospitals can be represented by a graph where an edge between two individuals is on throughout the time they are at the same ward. Like network topology, the temporal structure of edge activations can affect dynamics of systems interacting through the network, from disease contagion on the network of patients to information diffusion over an e-mail network. In this review, we present the emergent field of temporal networks, and discuss methods for analyzing topological and temporal structure and models for elucidating their relation to the behavior of dynamical systems. In the light of traditional network theory, one can see this framework as moving the information of when things happen from the dynamical system on the network, to the network itself. Since fundamental properties, such as the transitivity of edges, do not necessarily hold in temporal networks, many of these methods need to be quite different from those for static networks. The study of temporal networks is very interdisciplinary in nature. Reflecting this, even the object of study has many names-temporal graphs, evolving graphs, time-varying graphs, time-aggregated graphs, time-stamped graphs, dynamic networks, dynamic graphs, dynamical graphs, and so on. This review covers different fields where temporal graphs are considered, but does not attempt to unify related terminology-rather, we want to make papers readable across disciplines.

Holme, Petter; Saramäki, Jari

2012-10-01

103

Technological Networks  

NASA Astrophysics Data System (ADS)

The study of networks in the form of mathematical graph theory is one of the fundamental pillars of discrete mathematics. However, recent years have witnessed a substantial new movement in network research. The focus of the research is shifting away from the analysis of small graphs and the properties of individual vertices or edges to consideration of statistical properties of large scale networks. This new approach has been driven largely by the availability of technological networks like the Internet [12], World Wide Web network [2], etc. that allow us to gather and analyze data on a scale far larger than previously possible. At the same time, technological networks have evolved as a socio-technological system, as the concepts of social systems that are based on self-organization theory have become unified in technological networks [13]. In today’s society, we have a simple and universal access to great amounts of information and services. These information services are based upon the infrastructure of the Internet and the World Wide Web. The Internet is the system composed of ‘computers’ connected by cables or some other form of physical connections. Over this physical network, it is possible to exchange e-mails, transfer files, etc. On the other hand, the World Wide Web (commonly shortened to the Web) is a system of interlinked hypertext documents accessed via the Internet where nodes represent web pages and links represent hyperlinks between the pages. Peer-to-peer (P2P) networks [26] also have recently become a popular medium through which huge amounts of data can be shared. P2P file sharing systems, where files are searched and downloaded among peers without the help of central servers, have emerged as a major component of Internet traffic. An important advantage in P2P networks is that all clients provide resources, including bandwidth, storage space, and computing power. In this chapter, we discuss these technological networks in detail. The review is organized as follows. Section 2 presents an introduction to the Internet and different protocols related to it. This section also specifies the socio-technological properties of the Internet, like scale invariance, the small-world property, network resilience, etc. Section 3 describes the P2P networks, their categorization, and other related issues like search, stability, etc. Section 4 concludes the chapter.

Mitra, Bivas

104

Tokunaga Networks  

NASA Astrophysics Data System (ADS)

Tokunaga self-similar networks have a wide range of applications in the geosciences. The original application was to drainage networks. Tokunaga extended the Horton-Strahler length-order scaling of stream networks to include self-similar side branching. The addition of side branching provided important constraints on alternative models of river networks. A classic model for network generation is diffusion-limited aggregation (DLA). The branching statistics of DLA satisfy Tokunaga scaling. A modification of DLA can simulate river-network scaling. Aftershocks are another example of Tokunaga networks. Synthetic aftershock catalogs are generated using the BASS (branching aftershock sequence) model. Aftershocks of aftershocks play an essential role. Magnitude-order statistics are shown to satisfy Tokunaga scaling to a good approximation . Tokunaga scaling of a tree structure also provides an understanding of SOC (self-organized criticality). The forest-fire model provides the basis of our analysis. Trees are introduced one at a time but the loss of trees is dominated by the largest fires. Individual trees cascade from small tree clusters to large tree clusters by cluster coalescence. The coalescence of clusters generate a tree-like struction that satisfies Tokunaga statistics.

Newman, W. I.; Turcotte, D. L.

2009-12-01

105

DNA Structure and Supercoiling: Ribbons and a Yo-Yo Model  

ERIC Educational Resources Information Center

The double-helical structure of DNA is a pop cultural icon. Images of the DNA molecule appear in newspapers, popular journals, and advertisements. In addition to scientific instrument sales, the aura surrounding the central molecule of life has been used to sell everything from perfume to beverages and is the inspiration of items ranging from…

Van Horn, J. David

2011-01-01

106

The Yo-Yo IR2 test: physiological response, reliability, and application to elite soccer.  

PubMed

The purpose of this study was to compare the effects of resistance training performed on either a stable or unstable surface on performance tests in female soccer players. Nineteen National Collegiate Athletic Association Division II female soccer players were assigned to either an unstable training group (UST: 19.0 ± 0.47 years; 1.69 ± 6.4 m; 67.8 ± 7.7 kg) or a stable training group (ST: 19.6 ± 0.49 years; 1.64 ± 3.2 m; 62.7 ± 6.27 kg). Player positions were distributed evenly between the groups. Both the groups followed a 5-week periodized resistance training program designed to develop maximum muscular strength. The groups performed the same exercises during each workout, with the UST performing 2 of the exercises in each session on an unstable surface. Pretraining and posttraining measures of straight-line sprint speed, planned and reactive agility, aerobic capacity, and countermovement vertical jump (CMJ) were taken. Significant main effects for time were reported for straight-line sprint speed, planned agility, and reactive agility with both groups demonstrating improvements during the posttraining testing session. The ST demonstrated a significant increase in CMJ during the posttraining session (change in mean: 0.04 m) in contrast to the decline demonstrated by the UST (change in mean: -0.01 m). Performing resistance training exercises on an unstable surface confers no advantage over traditional resistance training exercises for improving the speed, agility, and aerobic capacity of female soccer players. Furthermore, the use of an unstable surface may inhibit the effects of resistance training on vertical jump height, an important variable in soccer performance. PMID:22130388

Oberacker, Lisa M; Davis, Shala E; Haff, G Gregory; Witmer, Chad A; Moir, Gavin L

2012-10-01

107

The Istria yo-yo - evidence for millennial seismic cycle in the northern Adriatic  

NASA Astrophysics Data System (ADS)

The Istria Peninsula in the northern Adriatic Sea (Croatia and Slovenia) is considered to be a nearly aseismic part of the Adriatic microplate, as opposed to the seismically active frontal ranges of the highly active Dinaric orogen. New archaeoseismological data from the Medieval Eufrasius cathedral in Pore? on the west coast of Istria demonstrate two, previously unknown major earthquakes, which occured approx. a millennium apart. Evidence for slow coastal uplift alternating with rapid subsidence allows to identify the seismic cycle. A marine notch, otherwise an excellent marker of sea level, extends along a 240 km segment of the northern Adriatic rocky coast, from Trieste to Zadar. We interpret the following history of vertical displacements: (1) Slow uplift, evidenced by the 1-2 m high, roofed marine notch oversized with respect to the microtidal regime of the Adriatic Sea. 0.5-1 m deep notches were etched into the coast between ~3000 BC until the 4-6th century AD (Faivre et al., 2010). (2) Rapid submergence of the notch to 1-2 m depth below sea level, dated by the construction of successive cathedrals of Pore? built on increasingly higher ground at the seaside (4-6th century AD); submergence of Cissa town on Pag island in 361 AD. (3) Slow uplift of less than 2 m between the construction of the last, Eufrasius cathedral in the 4-6th century AD and the ~1440 AD earthquake. No conspicuous notch were etched in the rocky shore during this period. (4) Rapid submergence of terrestrial sediments below sea level after 1400 AD (Faivre et al., 2011). Major earthquake damage in Pore? cathedral just before 1440 AD. (5) Slow uplift after 1440 AD, corroborated by three decades of high-precision levelling and recent GPS data (Rezo et al., 2010). No conspicuous notch etched in the rocky shore during this period. (6) Next major earthquake with subsidence on land and uplift in the sea with tsunami... when? In our interpretation of the seismic cycle, Istria is slowly raised, about 1-2 m in a millennium, during stress accumulation caused by a locked fault plane. Stress release produces sudden subsidence of the coast, which is recorded by subsided coastal features (marine notch, terrestrial sediments, cathedral of Pore?). We speculate that the thrust fault responsible for the earthquakes lies below the 2-5 km thick Triassic-Cretaceous carbonate platform sequence. The fault plane is assumed to be a gently sloping surface descending towards the east within the Permian-Lower Triassic clastic and evaporite beds. Over the centuries betweeen earthquakes the fault remained locked and the gradually increasing strain was manifested by the uplift (bulging) of the west coast of Istria, whereas the offshore portion of the hanging wall probably bowed downward above the fault. When rupture occurred, the bulge suddenly lowered back to the 'original' elevation. Meanwhile, the bowed, submarine portion of Istria relaxed and possibly triggered a tsunami. Continuing NNW-ward motion of the Adriatic microplate towards Eurasia, well-documented by GPS measurements, provides energy for stress accumulation of the next earthquake cycle. These observations challenge the current notion of Istria as the region of low seismic hazard and invite further paleoseismological research (M.K. OTKA K67.583; M.V. ARRS L1-5452 grant. B.S. contributed as Alexander von Humboldt Research Fellow) References: Faivre et al. (2010): GeoActa, SP 3, 125-134; Faivre et al. (2011): Quat. Int. 232, 132-143; Rezo et al. (2010): EJGE 15, 1835-1847

Kázmér, Miklós; Vrabec, Marko; Székely, Balázs

2014-05-01

108

Why network? Theoretical perspectives on networking  

Microsoft Academic Search

In recent years, networking and collaboration have become increasingly popular in education. However, there is at present a lack of attention to the theoretical basis of networking, which could illuminate when and when not to network and under what conditions networks are likely to be successful. In this paper, we will attempt to sketch the theoretical background to networking drawing

Daniel Muijs; Mel West; Mel Ainscow

2010-01-01

109

Protocols in optical networks -1 Optical Networks  

E-print Network

#12;Protocols in optical networks - 6 Goal: reduce complexity Ethernet Token Bus Token Ring FDDI DQDBProtocols in optical networks - 1 Optical Networks: from fiber transmission to photonic switching Protocols in Optical Networks Fabio Neri and Marco Mellia TLC Networks Group ­ Electronics Department e

Mellia, Marco

110

A Probabilistic Selection Network with Butterfly Networks  

E-print Network

A Probabilistic Selection Network with Butterfly Networks Takahiro Ikeda Department of Information the practical aspects of a butterfly network and shows some useful properties of a butterfly network, which of view that they have been concerned in the implementation of the network by using practical butterfly

Imai, Hiroshi

111

Sentient networks  

SciTech Connect

The engineering problems of constructing autonomous networks of sensors and data processors that can provide alerts for dangerous situations provide a new context for debating the question whether man-made systems can emulate the cognitive capabilities of the mammalian brain. In this paper we consider the question whether a distributed network of sensors and data processors can form ``perceptions`` based on sensory data. Because sensory data can have exponentially many explanations, the use of a central data processor to analyze the outputs from a large ensemble of sensors will in general introduce unacceptable latencies for responding to dangerous situations. A better idea is to use a distributed ``Helmholtz machine`` architecture in which the sensors are connected to a network of simple processors, and the collective state of the network as a whole provides an explanation for the sensory data. In general communication within such a network will require time division multiplexing, which opens the door to the possibility that with certain refinements to the Helmholtz machine architecture it may be possible to build sensor networks that exhibit a form of artificial consciousness.

Chapline, G.

1998-03-01

112

Neural Networks  

SciTech Connect

Physicists use large detectors to measure particles created in high-energy collisions at particle accelerators. These detectors typically produce signals indicating either where ionization occurs along the path of the particle, or where energy is deposited by the particle. The data produced by these signals is fed into pattern recognition programs to try to identify what particles were produced, and to measure the energy and direction of these particles. Ideally, there are many techniques used in this pattern recognition software. One technique, neural networks, is particularly suitable for identifying what type of particle caused by a set of energy deposits. Neural networks can derive meaning from complicated or imprecise data, extract patterns, and detect trends that are too complex to be noticed by either humans or other computer related processes. To assist in the advancement of this technology, Physicists use a tool kit to experiment with several neural network techniques. The goal of this research is interface a neural network tool kit into Java Analysis Studio (JAS3), an application that allows data to be analyzed from any experiment. As the final result, a physicist will have the ability to train, test, and implement a neural network with the desired output while using JAS3 to analyze the results or output. Before an implementation of a neural network can take place, a firm understanding of what a neural network is and how it works is beneficial. A neural network is an artificial representation of the human brain that tries to simulate the learning process [5]. It is also important to think of the word artificial in that definition as computer programs that use calculations during the learning process. In short, a neural network learns by representative examples. Perhaps the easiest way to describe the way neural networks learn is to explain how the human brain functions. The human brain contains billions of neural cells that are responsible for processing information [2]. Each one of these cells acts as a simple processor. When individual cells interact with one another, the complex abilities of the brain are made possible. In neural networks, the input or data are processed by a propagation function that adds up the values of all the incoming data. The ending value is then compared with a threshold or specific value. The resulting value must exceed the activation function value in order to become output. The activation function is a mathematical function that a neuron uses to produce an output referring to its input value. [8] Figure 1 depicts this process. Neural networks usually have three components an input, a hidden, and an output. These layers create the end result of the neural network. A real world example is a child associating the word dog with a picture. The child says dog and simultaneously looks a picture of a dog. The input is the spoken word ''dog'', the hidden is the brain processing, and the output will be the category of the word dog based on the picture. This illustration describes how a neural network functions.

Smith, Patrick I.

2003-09-23

113

Securing Ad Hoc Networks  

Microsoft Academic Search

Ad hoc networks are a new wireless networking paradigm for mobile hosts. Unlike traditional mobile wireless networks, ad hoc networks do not rely on any fixed infrastructure. Instead, hosts rely on each other to keep the network connected. The military tactical and other security-sensitive operations are still the main applications of ad hoc networks, although there is a trend to

Lidong Zhou; Zygmunt J. Haas

1999-01-01

114

Sensor Networks Communication strategies  

E-print Network

Outline Sensor Networks Communication strategies Follow on Distributed estimation in sensor@dsi.unifi.it February 1, 2007 A. Benavoli Fully Decentralized Networks #12;Outline Sensor Networks Communication strategies Follow on Outline 1 Sensor Networks An introduction to Sensor Networks Network architectures

Chisci, Luigi

115

Network Management Survey.  

ERIC Educational Resources Information Center

A study was made of management practices in different computer networks. The five networks were chosen as typical of different approaches to network implementation and management: Defense Advanced Research Projects Agency (ARPA) Network, MERIT Network, Triangle Universities Computation Center (TUCC), Oregon State Regional Network, and Tymnet (a…

Cotton, Ira W.

116

Tourism networks and computer networks  

E-print Network

The body of knowledge accumulated in recent years on the structure and the dynamics of complex networks has offered useful insights on the behaviour of many natural and artificial complex systems. The analysis of some of these, namely those formed by companies and institutions, however, has proved problematical mainly for the difficulties in collecting a reasonable amount of data. This contribution argues that the World Wide Web can provide an efficient and effective way to gather significant samples of networked socio-economic systems to be used for network analyses and simulations. The case discussed refers to a tourism destination, the fundamental subsystem of an industry which can be considered one of the most important in today's World economy.

Baggio, Rodolfo

2008-01-01

117

Progress in supervised neural networks  

Microsoft Academic Search

Theoretical results concerning the capabilities and limitations of various neural network models are summarized, and some of their extensions are discussed. The network models considered are divided into two basic categories: static networks and dynamic networks. Unlike static networks, dynamic networks have memory. They fall into three groups: networks with feedforward dynamics, networks with output feedback, and networks with state

D. R. Hush; B. G. Horne

1993-01-01

118

Sensor networks Opportunities for theory  

E-print Network

Sensor networks Opportunities for theory The future Sensor Networks and the Future of Networked Networks and the Future of Networked Computation #12;Sensor networks Opportunities for theory The future Rationale Classical networks Sensor networks The present The future Why wireless sensor networks? Question

Feigenbaum, Joan

119

Global Networking.  

ERIC Educational Resources Information Center

Discusses the state of the Internet. Highlights include the magnitude of the infrastructure, costs, its increasing pace, constraints in international links, provision of network capacity to homes and small businesses, cable television modems, political and cultural problems, the digital library concept, search engines, the failure of personal…

Lynch, Clifford

1997-01-01

120

Knowledge Networks  

ERIC Educational Resources Information Center

The blogosphere and the Internet are both examples of complex, self-organizing networks. So too is the world of academic publishing. Some faculty members are prolific article and book writers. Their publications often are hubs, or even superhubs, in the scholarly literature, cited regularly by others. Some scholars might just be nodes, with…

McLeod, Scott

2008-01-01

121

Network Management Framework for Wireless Sensor Networks  

NASA Astrophysics Data System (ADS)

Network Management is the process of managing, monitoring, and controlling the network. Conventional network management was based on wired network which is heavy and unsuitable for resource constrained WSNs. WSNs can have large scale network and it is impossible to manage each node individually. Also, polling mechanism of Simple Network Management Protocol (SNMP) impose heavy management traffic overhead. Since management messages consume resources of WSNs, it can affect the performance of the network. Therefore, it is necessary for WSNs to perform energy efficient network management. In this paper, we will propose network management framework. We will introduce cluster-based network management architecture, and classify the Management Information Base (MIB) according to their characteristics. Then, we will define management messages and message exchange operation for each kind of MIB. The analysis result of the management overhead indicates that the proposed framework can reduce management traffic compared to polling mechanism.

Kim, Jaewoo; Jeon, Hahnearl; Lee, Jaiyong

122

TELECOM 1 multiservices network  

NASA Astrophysics Data System (ADS)

The main objectives of the TELECOM 1 French domestic satellite project are to set up a business communication network which is to carry a wide range of digital services including data, voice, and pictures between a number of small earth stations located on the subscribers' premises. The parallel development of terrestrial specialized services networks has enabled the fitting of the TELECOM 1 network with high interworking capabilities with these networks. It has also allowed TELECOM 1 to be designed as the basis of the Future Integrated Services Digital Network. The TELECOM 1 network consists of the terrestrial network, the satellite network, and the maintenance network. Various elements which include the terrestrial network; the satellite network, and its modulation, TDMA frame and terminals; the System Management Center; the signalling system; and the demand assignment operation which are involved in the operation of the multiservices network are presented. The TELECOM 1 network evolution until 1990 through the rapid development of the ISDN is discussed.

Lombard, D.; Ramat, P.; Rancy, F.

123

Nested Neural Networks  

NASA Technical Reports Server (NTRS)

Report presents analysis of nested neural networks, consisting of interconnected subnetworks. Analysis based on simplified mathematical models more appropriate for artificial electronic neural networks, partly applicable to biological neural networks. Nested structure allows for retrieval of individual subpatterns. Requires fewer wires and connection devices than fully connected networks, and allows for local reconstruction of damaged subnetworks without rewiring entire network.

Baram, Yoram

1992-01-01

124

Network exception handlers: host-network control in enterprise networks  

Microsoft Academic Search

Enterprise network architecture and management have followed the Internet's design principles despite different requirements and characteristics: enterprise hosts are administered by a single authority, which intrinsically assigns different values to traffic from different business applications. We advocate a new approach where hosts are no longer relegated to the network's periphery, but actively participate in network-related decisions. To enable host participation,

Thomas Karagiannis; Richard Mortier; Antony Rowstron

2008-01-01

125

NHLBI ARDS Network  

MedlinePLUS

... Patient and Family Information ARDSNet Studies Related Links Network Sites For Clinicians & Researchers For the General Public ... of the factors considered in the selection of network clinical trials? What is the ARDS Network? Who ...

126

National Lymphedema Network  

MedlinePLUS

... and article archives // Knowledge and support National Lymphedema Network NLN Position Papers The NLN Position Papers reflect ... list. twitter Facebook LinkedIn Copyright 2014 National Lymphedema Network © 2013 National Lymphedema Network 225 Bush Street, Suite ...

127

Animal transportation networks  

PubMed Central

Many group-living animals construct transportation networks of trails, galleries and burrows by modifying the environment to facilitate faster, safer or more efficient movement. Animal transportation networks can have direct influences on the fitness of individuals, whereas the shape and structure of transportation networks can influence community dynamics by facilitating contacts between different individuals and species. In this review, we discuss three key areas in the study of animal transportation networks: the topological properties of networks, network morphogenesis and growth, and the behaviour of network users. We present a brief primer on elements of network theory, and then discuss the different ways in which animal groups deal with the fundamental trade-off between the competing network properties of travel efficiency, robustness and infrastructure cost. We consider how the behaviour of network users can impact network efficiency, and call for studies that integrate both network topology and user behaviour. We finish with a prospectus for future research. PMID:25165598

Perna, Andrea; Latty, Tanya

2014-01-01

128

Complex Networks and Graphs  

NSDL National Science Digital Library

Students learn about complex networks and how to represent them using graphs. They also learn that graph theory is a useful mathematical tool for studying complex networks in diverse applications of science and engineering, such as neural networks in the brain, biochemical reaction networks in cells, communication networks, such as the internet, and social networks. Topics covered include set theory, defining a graph, as well as defining the degree of a node and the degree distribution of a graph.

2014-09-18

129

The deep space network  

NASA Technical Reports Server (NTRS)

Summaries are given of Deep Space Network progress in flight project support, tracking and data acquisition research and technology, network engineering, hardware and software implementation, and operations.

1975-01-01

130

Energy aware network coding in wireless networks  

E-print Network

Energy is one of the most important considerations in designing reliable low-power wireless communication networks. We focus on the problem of energy aware network coding. In particular, we investigate practical energy ...

Shi, Xiaomeng, Ph. D. Massachusetts Institute of Technology

2012-01-01

131

ENLIGHT Network  

E-print Network

State-of-the-art techniques borrowed from particle accelerators and detectors are a key element in hadrontherapy and several European projects are actively fostering the collaboration amongst the various disciplines and countries. ENLIGHT was established in 2002 to coordinate these European efforts in hadron therapy. The ENLIGHT network is formed by the European hadrontherapy Community, with more than 300 participants from twenty European countries. A major achievement of ENLIGHT has been the blending of traditionally separate communities so that clinicians, physicists, biologists and engineers with experience and interest in particle therapy are working together.

Ballantine, A;; Dixon-Altaber, H;; Dosanjh, M;; Kuchina, L

2011-01-01

132

Communications Network  

NASA Technical Reports Server (NTRS)

The Multi-Compatible Network Interface Unit (MCNIU) is intended to connect the space station's communications and tracking, guidance and navigation, life support, electric power, payload data, hand controls, display consoles and other systems, and also communicate with diverse processors. Honeywell is now marketing MCNIU commercially. It has applicability in certain military operations or civil control centers. It has nongovernment utility among large companies, universities and research organizations that transfer large amounts of data among workstations and computers. *This product is no longer commercially available.

1990-01-01

133

Computer Networks and Networking: A Primer.  

ERIC Educational Resources Information Center

Provides a basic introduction to computer networks and networking terminology. Topics addressed include modems; the Internet; TCP/IP (Transmission Control Protocol/Internet Protocol); transmission lines; Internet Protocol numbers; network traffic; Fidonet; file transfer protocol (FTP); TELNET; electronic mail; discussion groups; LISTSERV; USENET;…

Collins, Mauri P.

1993-01-01

134

PROXIMITY MODE INCLINED UV LITHOGRAPHY Yong-Kyu Yoon and Mark G. Allen  

E-print Network

, nozzles with various orifice sizes of 0 m to 255 m, a height of 250 m, a side wall tilting angle of 25 and the substrate g, and are described as follows: doti: inner diameter of orifice tip= 2*g/tan i-dm (1) doto: outer diameter of orifice tip= 2*g/tan i+dm (2) dori: inner diameter of orifice root= 2*g/tan i-dm+2*t*tan r (3

135

Spectroscopic networks  

NASA Astrophysics Data System (ADS)

Approaches related to graph theory are investigated which allow a better understanding and yield routes for systematic enlargement and improvement of experimental spectroscopic line lists of molecules. The proposed protocols are based on the fact that quantum mechanics builds, in a simple and natural way, large-scale, weighted, undirected graphs, whereby the vertices are discrete energy levels, the edges are transitions, and the weights are transition intensities. A small part of molecular quantum mechanical graphs can be probed experimentally via high-resolution spectroscopic techniques, while the complete graph encompassing the full line list information for a given molecule can be obtained through sophisticated variational nuclear motion computations. Both approaches yield what one may call spectroscopic networks (SNs). It is shown on the example of the HD 16O isotopologue of the water molecule that both the measured and the computed one-photon absorption SNs have a scale-free behavior with all of the usual consequences, including appearance of hubs, robustness, error tolerance, and the "small-world" property. For the complete computed "deterministic" network the scale-free property holds if a realistic intensity cut-off is employed during its build-up, thus introducing "stochasticity". The graph-theoretical view of molecular spectra offers several new ideas for improving the accuracy and robustness of the information systems containing high-resolution spectroscopic data.

Császár, Attila G.; Furtenbacher, Tibor

2011-04-01

136

Networking the Classroom.  

ERIC Educational Resources Information Center

This issue of "CQ Researcher" examines the theme of computer networking in the classroom and discusses uses past and present. It begins with an essay by Christopher Conte that discusses: "Does computer networking really enhance learning? Are teachers adequately prepared to take advantage of computer networking? Will computer networking promote…

Stencel, Sandra, Ed.; And Others

1995-01-01

137

Network epistemology Discrete models  

E-print Network

Network epistemology Discrete models Continuous models Social Structure and Social Influence A study in network epistemology Kevin J.S. Zollman Social Dynamics Seminar Kevin J.S. Zollman Social Structure and Social Influence #12;Network epistemology Discrete models Continuous models Network

Zollman, Kevin

138

The constitution of networks  

Microsoft Academic Search

The idea of a constitution of networks may be a useful addition to our ways of understanding what happens within the business landscape. We describe a constitution of networks as a system of values, norms, rules and other conventions that are shared by actors in business networks. Whether by intention or not, the constitution of networks provides a framework within

Stefanos Mouzas; David Ford

2009-01-01

139

Designing Secure Library Networks.  

ERIC Educational Resources Information Center

Focuses on designing a library network to maximize security. Discusses UNIX and file servers; connectivity to campus, corporate networks and the Internet; separation of staff from public servers; controlling traffic; the threat of network sniffers; hubs that eliminate eavesdropping; dividing the network into subnets; Switched Ethernet;…

Breeding, Michael

1997-01-01

140

Reti Fotoniche (Optical Networks)  

E-print Network

Ethernet n Storagearea networks: Fibre Channel Reti ottiche di seconda generazione: n reti broadcast to Communication Protocols Total Network VisibilityTM Courtesy Network General Corporation OSI Layers Application 7 Presentation 6 Session 5 Transport 4 Network 3 Logical Link 2 Physical 1 Ridurre la complessità Ethernet Token

Mellia, Marco

141

MONET: multiwavelength optical networking  

Microsoft Academic Search

This paper presents an overview of the multiwavelength optical networking (MONET) program and summarizes its vision. The program objective is to advance, demonstrate, and integrate network architecture and economics, advanced multiwavelength technology, and network management and control to achieve high capacity, reconfigurable, high performance, reliable multiwavelength optical networks, with scalability to national scale, for both commercial and specialized government applications.

Richard E. Wagner; Rod C. Alferness; A. A. M. Saleh; Matthew S. Goodman

1996-01-01

142

Directed network modules  

Microsoft Academic Search

A search technique locating network modules, i.e. internally densely connected groups of nodes in directed networks is introduced by extending the clique percolation method originally proposed for undirected networks. After giving a suitable definition for directed modules we investigate their percolation transition in the Erdos Rényi graph both analytically and numerically. We also analyse four real-world directed networks, including Google's

Gergely Palla; Illés J. Farkas; Péter Pollner; Imre Derényi; Tamás Vicsek

2007-01-01

143

Secure Ad hoc Networking  

Microsoft Academic Search

The ad hoc networking technology can enable novel civilian and military applications. However, ad hoc networking protocols are vulnerable to a wide range of attacks. The design of defense mechanisms is a challenging problem, especially in comparison to securing traditional, fixed-infrastructure networks. In this paper, we discuss challenges and guidelines to secure ad hoc networking protocols, and describe a protocol

Panagiotis Papadimitratos

2006-01-01

144

Network operating systems  

Microsoft Academic Search

Network operating systems represent a promising approach for realizing the full potential of computer communication networks. A network operating system (NOS) is a collection of software and protocols that allow a set of autonomous computers, which are interconnected by a computer network, to be used together in a convenient and cost effective manner. This report investigates some of the technical

R. H. Thomas; R. E. Schantz; H. C. Forsdick

1978-01-01

145

FES Science Network Requirements  

E-print Network

FES Science Network Requirements Report of the Fusion Energy Sciences Network Requirements Workshop Conducted March 13 and 14, 2008 #12;FES Science Network Requirements Workshop Fusion Energy Sciences Program Office, DOE Office of Science Energy Sciences Network Gaithersburg, MD ­ March 13 and 14, 2008 ESnet

Geddes, Cameron Guy Robinson

146

Network observability: theory  

SciTech Connect

A complete theory of network observability is presented. Starting from a fundamental notion of the observability of a network, a number of basic facts relating to network observability, unobservable states, unobservable branches, observable islands, relevancy of measurements, etc. are derived. Simple and efficient algorithms can be developed based on these basic facts to test network observability, identify observable islands and place measurements for observability.

Monticelli, A.; Wu, F.F.

1985-05-01

147

K-winner networks  

Microsoft Academic Search

A special class of mutually inhibitory networks is analyzed, and parameters for reliable K-winner performance are presented. The network dynamics are modeled using interactive activation, and results are compared with the sigmoid model. For equal external inputs, network parameters that select the units with the larger initial activations (the network converges to the nearest stable state) are derived. Conversely, for

W. J. Wolfe; D. Mathis; C. Anderson; J. Rothman; M. Gottler; G. Brady; R. Walker; G. Duane; G. Alaghband

1991-01-01

148

Network epidemiology and plant trade networks  

PubMed Central

Models of epidemics in complex networks are improving our predictive understanding of infectious disease outbreaks. Nonetheless, applying network theory to plant pathology is still a challenge. This overview summarizes some key developments in network epidemiology that are likely to facilitate its application in the study and management of plant diseases. Recent surveys have provided much-needed datasets on contact patterns and human mobility in social networks, but plant trade networks are still understudied. Human (and plant) mobility levels across the planet are unprecedented—there is thus much potential in the use of network theory by plant health authorities and researchers. Given the directed and hierarchical nature of plant trade networks, there is a need for plant epidemiologists to further develop models based on undirected and homogeneous networks. More realistic plant health scenarios would also be obtained by developing epidemic models in dynamic, rather than static, networks. For plant diseases spread by the horticultural and ornamental trade, there is the challenge of developing spatio-temporal epidemic simulations integrating network data. The use of network theory in plant epidemiology is a promising avenue and could contribute to anticipating and preventing plant health emergencies such as European ash dieback. PMID:24790128

Pautasso, Marco; Jeger, Mike J.

2014-01-01

149

Network epidemiology and plant trade networks.  

PubMed

Models of epidemics in complex networks are improving our predictive understanding of infectious disease outbreaks. Nonetheless, applying network theory to plant pathology is still a challenge. This overview summarizes some key developments in network epidemiology that are likely to facilitate its application in the study and management of plant diseases. Recent surveys have provided much-needed datasets on contact patterns and human mobility in social networks, but plant trade networks are still understudied. Human (and plant) mobility levels across the planet are unprecedented-there is thus much potential in the use of network theory by plant health authorities and researchers. Given the directed and hierarchical nature of plant trade networks, there is a need for plant epidemiologists to further develop models based on undirected and homogeneous networks. More realistic plant health scenarios would also be obtained by developing epidemic models in dynamic, rather than static, networks. For plant diseases spread by the horticultural and ornamental trade, there is the challenge of developing spatio-temporal epidemic simulations integrating network data. The use of network theory in plant epidemiology is a promising avenue and could contribute to anticipating and preventing plant health emergencies such as European ash dieback. PMID:24790128

Pautasso, Marco; Jeger, Mike J

2014-01-01

150

Epidemics on interconnected networks  

NASA Astrophysics Data System (ADS)

Populations are seldom completely isolated from their environment. Individuals in a particular geographic or social region may be considered a distinct network due to strong local ties but will also interact with individuals in other networks. We study the susceptible-infected-recovered process on interconnected network systems and find two distinct regimes. In strongly coupled network systems, epidemics occur simultaneously across the entire system at a critical infection strength ?c, below which the disease does not spread. In contrast, in weakly coupled network systems, a mixed phase exists below ?c of the coupled network system, where an epidemic occurs in one network but does not spread to the coupled network. We derive an expression for the network and disease parameters that allow this mixed phase and verify it numerically. Public health implications of communities comprising these two classes of network systems are also mentioned.

Dickison, Mark; Havlin, S.; Stanley, H. E.

2012-06-01

151

Networks in Cell Biology  

NASA Astrophysics Data System (ADS)

Introduction; 1. Network views of the cell Paolo De Los Rios and Michele Vendruscolo; 2. Transcriptional regulatory networks Sarath Chandra Janga and M. Madan Babu; 3. Transcription factors and gene regulatory networks Matteo Brilli, Elissa Calistri and Pietro Lió; 4. Experimental methods for protein interaction identification Peter Uetz, Björn Titz, Seesandra V. Rajagopala and Gerard Cagney; 5. Modeling protein interaction networks Francesco Rao; 6. Dynamics and evolution of metabolic networks Daniel Segré; 7. Hierarchical modularity in biological networks: the case of metabolic networks Erzsébet Ravasz Regan; 8. Signalling networks Gian Paolo Rossini; Appendix 1. Complex networks: from local to global properties D. Garlaschelli and G. Caldarelli; Appendix 2. Modelling the local structure of networks D. Garlaschelli and G. Caldarelli; Appendix 3. Higher-order topological properties S. Ahnert, T. Fink and G. Caldarelli; Appendix 4. Elementary mathematical concepts A. Gabrielli and G. Caldarelli; References.

Buchanan, Mark; Caldarelli, Guido; De Los Rios, Paolo; Rao, Francesco; Vendruscolo, Michele

2010-05-01

152

Spectroscopic networks  

NASA Astrophysics Data System (ADS)

Approaches related to graph theory are given which allow a better understanding of and yield routes for systematic enlargement and improvement of experimental spectroscopic line lists of molecules. The protocols are based on the fact that the information in line lists can be related to large-scale, weighted, undirected graphs, whereby the vertices are discrete energy levels, the edges are transitions, and the weights are transition intensities. The resulting graph is what one may call a spectroscopic network (SN). It is shown on the example of the HD16O isotopologue of the water molecule that both its measured and first-principles one-photon absorption SNs have a scale-free behavior with all of the usual consequences, including appearance of hubs, robustness, error tolerance, and the "small-world" property. The graph-theoretical view of molecular spectra offers several new ideas for improving the accuracy and robustness of the information systems containing high-resolution spectroscopic data.

Csaszar, A. G.; Furtenbacher, T.

2011-05-01

153

Native Networks  

NSDL National Science Digital Library

Over the past few years, Native Americans have made significant contributions in a host of different media, including television, radio, and film. Involved in all aspects of this type of artistic and cultural expression, many Native Americans have also looked for a way to disseminate their substantial efforts in this arena. Fortunately, there is the Native Networks website (first launched in 2001), designed to provide information about such creations. The website was created by the Film and Video Center of the National Museum of the American Indian, and contains information about upcoming Native American film festivals and âÂÂclose-upâ profiles of people actively working in the field. Some of these features include material on the indigenous video makers in Mexico and an in-depth look at the film âÂÂHouse Made of DawnâÂÂ, which deals with a young Pueblo man in crisis. The site is available in both Spanish and English versions. [KMG

154

Interconnection networks  

DOEpatents

A network of interconnected processors is formed from a vertex symmetric graph selected from graphs GAMMA/sub d/(k) with degree d, diameter k, and (d + 1)exclamation/ (d /minus/ k + 1)exclamation processors for each d greater than or equal to k and GAMMA/sub d/(k, /minus/1) with degree d /minus/ 1, diameter k + 1, and (d + 1)exclamation/(d /minus/ k + 1)exclamation processors for each d greater than or equal to k greater than or equal to 4. Each processor has an address formed by one of the permutations from a predetermined sequence of letters chosen a selected number of letters at a time, and an extended address formed by appending to the address the remaining ones of the predetermined sequence of letters. A plurality of transmission channels is provided from each of the processors, where each processor has one less channel than the selected number of letters forming the sequence. Where a network GAMMA/sub d/(k, /minus/1) is provided, no processor has a channel connected to form an edge in a direction delta/sub 1/. Each of the channels has an identification number selected from the sequence of letters and connected from a first processor having a first extended address to a second processor having a second address formed from a second extended address defined by moving to the front of the first extended address the letter found in the position within the first extended address defined by the channel identification number. The second address is then formed by selecting the first elements of the second extended address corresponding to the selected number used to form the address permutations. 9 figs.

Faber, V.; Moore, J.W.

1988-06-20

155

Terminal Attractors In Neural Networks  

NASA Technical Reports Server (NTRS)

Neural networks made to "learn" faster. Report presents theoretical study of terminal attractors in neural networks. Includes systematic analysis of applications to activation dynamics of neural networks.

Zak, Michail A.

1991-01-01

156

INTERACTING WITH SOCIAL NETWORKS TO IMPROVE HEALTHCARE BODY SENSOR NETWORKS  

E-print Network

INTERACTING WITH SOCIAL NETWORKS TO IMPROVE HEALTHCARE BODY SENSOR NETWORKS by DAVID BAUSCHLICHER.........................................................................................3 2.1 Wireless Sensor Networks.............................................................3 2.2 Body Sensor Networks..................................................................5 2.2.1 Energy

Miles, Will

157

Knitted Complex Networks  

E-print Network

To a considerable extent, the continuing importance and popularity of complex networks as models of real-world structures has been motivated by scale free degree distributions as well as the respectively implied hubs. Being related to sequential connections of edges in networks, paths represent another important, dual pattern of connectivity (or motif) in complex networks (e.g., paths are related to important concepts such as betweeness centrality). The present work proposes a new supercategory of complex networks which are organized and/or constructed in terms of paths. Two specific network classes are proposed and characterized: (i) PA networks, obtained by star-path transforming Barabasi-Albert networks; and (ii) PN networks, built by performing progressive paths involving all nodes without repetition. Such new networks are important not only from their potential to provide theoretical insights, but also as putative models of real-world structures. The connectivity structure of these two models is investig...

Costa, Luciano da Fontoura

2007-01-01

158

Parallel Consensual Neural Networks  

NASA Technical Reports Server (NTRS)

A new neural network architecture is proposed and applied in classification of remote sensing/geographic data from multiple sources. The new architecture is called the parallel consensual neural network and its relation to hierarchical and ensemble neural networks is discussed. The parallel consensual neural network architecture is based on statistical consensus theory. The input data are transformed several times and the different transformed data are applied as if they were independent inputs and are classified using stage neural networks. Finally, the outputs from the stage networks are then weighted and combined to make a decision. Experimental results based on remote sensing data and geographic data are given. The performance of the consensual neural network architecture is compared to that of a two-layer (one hidden layer) conjugate-gradient backpropagation neural network. The results with the proposed neural network architecture compare favorably in terms of classification accuracy to the backpropagation method.

Benediktsson, J. A.; Sveinsson, J. R.; Ersoy, O. K.; Swain, P. H.

1993-01-01

159

Wayfinding in Social Networks  

NASA Astrophysics Data System (ADS)

With the recent explosion of popularity of commercial social-networking sites like Facebook and MySpace, the size of social networks that can be studied scientifically has passed from the scale traditionally studied by sociologists and anthropologists to the scale of networks more typically studied by computer scientists. In this chapter, I will highlight a recent line of computational research into the modeling and analysis of the small-world phenomenon - the observation that typical pairs of people in a social network are connected by very short chains of intermediate friends - and the ability of members of a large social network to collectively find efficient routes to reach individuals in the network. I will survey several recent mathematical models of social networks that account for these phenomena, with an emphasis on both the provable properties of these social-network models and the empirical validation of the models against real large-scale social-network data.

Liben-Nowell, David

160

Morphological neural networks  

SciTech Connect

The theory of artificial neural networks has been successfully applied to a wide variety of pattern recognition problems. In this theory, the first step in computing the next state of a neuron or in performing the next layer neural network computation involves the linear operation of multiplying neural values by their synaptic strengths and adding the results. Thresholding usually follows the linear operation in order to provide for nonlinearity of the network. In this paper we introduce a novel class of neural networks, called morphological neural networks, in which the operations of multiplication and addition are replaced by addition and maximum (or minimum), respectively. By taking the maximum (or minimum) of sums instead of the sum of products, morphological network computation is nonlinear before thresholding. As a consequence, the properties of morphological neural networks are drastically different than those of traditional neural network models. In this paper we consider some of these differences and provide some particular examples of morphological neural network.

Ritter, G.X.; Sussner, P. [Univ. of Florida, Gainesville, FL (United States)

1996-12-31

161

Gossip on Weighted Networks  

E-print Network

We investigate how suitable a weighted network is for gossip spreading. The proposed model is based on the gossip spreading model introduced by Lind et.al. on unweighted networks. Weight represents "friendship." Potential spreader prefers not to spread if the victim of gossip is a "close friend". Gossip spreading is related to the triangles and cascades of triangles. It gives more insight about the structure of a network. We analyze gossip spreading on real weighted networks of human interactions. 6 co-occurrence and 7 social pattern networks are investigated. Gossip propagation is found to be a good parameter to distinguish co-occurrence and social pattern networks. As a comparison some miscellaneous networks and computer generated networks based on ER, BA, WS models are also investigated. They are found to be quite different than the human interaction networks.

Tasgin, Mursel

2012-01-01

162

Percolation of a general network of networks  

NASA Astrophysics Data System (ADS)

Percolation theory is an approach to study the vulnerability of a system. We develop an analytical framework and analyze the percolation properties of a network composed of interdependent networks (NetONet). Typically, percolation of a single network shows that the damage in the network due to a failure is a continuous function of the size of the failure, i.e., the fraction of failed nodes. In sharp contrast, in NetONet, due to the cascading failures, the percolation transition may be discontinuous and even a single node failure may lead to an abrupt collapse of the system. We demonstrate our general framework for a NetONet composed of n classic Erd?s-Rényi (ER) networks, where each network depends on the same number m of other networks, i.e., for a random regular network (RR) formed of interdependent ER networks. The dependency between nodes of different networks is taken as one-to-one correspondence, i.e., a node in one network can depend only on one node in the other network (no-feedback condition). In contrast to a treelike NetONet in which the size of the largest connected cluster (mutual component) depends on n, the loops in the RR NetONet cause the largest connected cluster to depend only on m and the topology of each network but not on n. We also analyzed the extremely vulnerable feedback condition of coupling, where the coupling between nodes of different networks is not one-to-one correspondence. In the case of NetONet formed of ER networks, percolation only exhibits two phases, a second order phase transition and collapse, and no first order percolation transition regime is found in the case of the no-feedback condition. In the case of NetONet composed of RR networks, there exists a first order phase transition when the coupling strength q (fraction of interdependency links) is large and a second order phase transition when q is small. Our insight on the resilience of coupled networks might help in designing robust interdependent systems.

Gao, Jianxi; Buldyrev, Sergey V.; Stanley, H. Eugene; Xu, Xiaoming; Havlin, Shlomo

2013-12-01

163

Network exception handlers: host-network control in enterprise networks  

Microsoft Academic Search

Enterprise network architecture and management have followed the Internet's design principles despite different requirements and char- acteristics: enterprise hosts are administered by a single authority, which intrinsically assigns different values to traffic from different business applications. We advocate a new approach where hosts are no longer relegated tothenetwork'speriphery, butactively participateinnetwork-related decisions. To enable host participation, network information, such as dynamic

Thomas Karagiannis; Richard Mortier; Antony I. T. Rowstron

2008-01-01

164

India Network Gopher  

NSDL National Science Digital Library

The India Network Gopher: The network of the Asian Indian Community, the India Network of mailing lists and gopher and Web sites was established to discuss and provide information about issues related to India facing Indians living abroad. The India Network and Research Foundation was established in 1993 to provide stable network resources and to fund a graduate assistantship to work on network related chores. The 'welcome' file includes detailed information about joining their mailing lists, such as the India News Digest and the list for faculty of Indian origin.

165

Rare Diseases Clinical Research Network  

MedlinePLUS

... Network Conference on Clinical Research on Rare Diseases Network Resources The Rare Diseases Clinical Research Network (RDCRN), ... Former Partners of the Rare Diseases Clinical Research Network [+] Clinical Research Consortium for Spinocerebellar Ataxias Spinocerebellar ataxia: ...

166

EMPOWER: A Network Emulator for Wireless and Wireline Networks  

Microsoft Academic Search

The increasing need of protocol development environments and network performance evaluation tools gives rise to the research of flexible, scalable, and accurate network emulators. The desired network emulator should be able to facilitate the emulation of either wireline or wireless networks. In the case when network topology is critical to the underlying network protocol, the emulator should provide specific mechanisms

Pei Zheng; Lionel M. Ni

2003-01-01

167

Distributed network computing over local ATM networks  

SciTech Connect

Communication between processors has long been the bottleneck of distributed network computing. However, recent progress in switch-based high-speed Local Area Networks (LANs) may be changing this situation. Asynchronous Transfer Mode (ATM) is one of the most widely-accepted and emerging high-speed network standards which can potentially satisfy the communication needs of distributed network computing. In this paper, the authors investigate distributed network computing over local ATM networks. They first study the performance characteristics involving end-to-end communication in an environment that includes several types of workstations interconnected via a Fore Systems` ASX-100 ATM Switch. They then compare the communication performance of four different Application Programming Interfaces (APIs). The four APIs were Fore Systems ATM API, BSD socket programming interface, Sun`s Remote Procedure Call (RPC), and the Parallel Virtual Machine (PVM) message passing library. Each API represents distributed programming at a different communication protocol layer. They evaluate parallel Matrix Multiplication over the local ATM network. The experimental results show that network computing is promising over local ATM networks.

Lin, M.; Hsieh, J.; Du, D.H.C.; MacDonald, J.A. [Univ. of Minnesota, Minneapolis, MN (United States); Thomas, J.P. [Minnesota Supercomputer Center Inc., Minneapolis, MN (United States)

1994-12-31

168

OncoArray Network  

Cancer.gov

The overall goal of the OncoArray Network is to gain new insight into the genetic architecture and mechanisms underlying breast, ovarian, prostate, colorectal, and lung cancers. The Network's major aim is to discover new cancer susceptibility variants.

169

Fiber wireless networks  

NASA Astrophysics Data System (ADS)

Broadband wireless networks based on a number of new frequency windows at higher microwave and millimeter-wave frequencies have been actively pursued to provide ultra-high bandwidth services over a wireless networks. These networks will have a large number of antenna base-stations with high throughput. Significant reductions in antenna base-station complexity can be achieved if most of the signal routing and switching functions centralized at a central office in the network. In such a network, fiber feed networks can be effectively deployed to provide high bandwidth interconnections between multiple antenna base-stations and the central office. With wavelength division multiplexing, efficient optical fiber feed network architectures could be realised to provide interconnection to a large number of antenna base-stations. In this paper, we present an over view of our recent research into system technologies for fiber wireless networks.

Nirmalathas, A.; Bakaul, M.; Lim, C.; Novak, D.; Waterhouse, R.

2005-11-01

170

The deep space network  

NASA Technical Reports Server (NTRS)

A report is given of the Deep Space Networks progress in (1) flight project support, (2) tracking and data acquisition research and technology, (3) network engineering, (4) hardware and software implementation, and (5) operations.

1979-01-01

171

The deep space network  

NASA Technical Reports Server (NTRS)

A Deep Space Network progress report is presented dealing with in flight project support, tracking and data acquisition research and technology, network engineering, hardware and software implementation, and operations.

1977-01-01

172

Congenital Heart Information Network  

MedlinePLUS

... heart defects. Important Notice The Congenital Heart Information Network website is temporarily out of service. Please join ... and Uwe Baemayr for The Congenital Heart Information Network Exempt organization under Section 501(c)3. Copyright © ...

173

Juvenile Scleroderma Network  

MedlinePLUS

... and your family can help. What if Juvenile Scleroderma Network earned a penny every time you searched ... goodsearch.com and be sure to enter Juvenile Scleroderma Network as the charity you want to support. ...

174

The deep space network  

NASA Technical Reports Server (NTRS)

The functions and facilities of the Deep Space Network are considered. Progress in flight project support, tracking and data acquisition research and technology, network engineering, hardware and software implementation, and operations is reported.

1980-01-01

175

Connectibles : tangible social networking  

E-print Network

This thesis presents "Connectibles," an instantiation of a tangible social network, a new type of social network application rooted in physical objects and real world social behavior. This research is inspired by social ...

Kalanithi, Jeevan James

2007-01-01

176

Using Neural Networks  

E-print Network

unmeasurable parameters in a first-principles mathematical model of the engine. The network is trained using data derived from measured data taken on an auxiliary power unit (APU) engine (from an aircraft application). A discussion of the neural network...

Gabel, S.

177

The deep space network  

NASA Technical Reports Server (NTRS)

Progress is reported in flight project support, tracking and data acquisition research and technology, network engineering, hardware and software implementation, and operations. The functions and facilities of the Deep Space Network are emphasized.

1979-01-01

178

The deep space network  

NASA Technical Reports Server (NTRS)

The facilities, programming system, and monitor and control system for the deep space network are described. Ongoing planetary and interplanetary flight projects are reviewed, along with tracking and ground-based navigation, communications, and network and facility engineering.

1977-01-01

179

Valley Networks  

NASA Technical Reports Server (NTRS)

[figure removed for brevity, see original site]

Released 30 July 2003

Valley networks are a relatively common feature in the southern highlands of Mars. This THEMIS visible image contains several of these small channels. Some appear clustered near the smaller crater at the top of the image. There is still some debate over the origin of these enigmatic martian landforms. Were they caused by overland flow after precipitation, underground sapping, or a combination of both?

Image information: VIS instrument. Latitude -40.6, Longitude 165.2 East (194.8 West). 19 meter/pixel resolution.

Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

2003-01-01

180

Electro-Magnetic Earthquake Bursts and Critical Rupture of Peroxy Bond Networks in Rocks  

E-print Network

We propose a mechanism for the low frequency electromagnetic emissions and other electromagnetic phenomena which have been associated with earthquakes. The mechanism combines the critical earthquake concept and the concept of crust acting as a charging electric battery under increasing stress. The electric charges are released by activation of dormant charge carriers in the oxygen anion sublattice, called peroxy bonds or positive hole pairs (PHP), where a PHP represents an $O_3X/^{OO}\\backslash YO_3$ with $X,Y = Si^{4+}, Al^{3+}...$, i.e. an $O^-$ in a matrix of $O^{2-}$ of silicates. We propose that PHP are activated by plastic deformations during the slow cooperative build-up of stress and the increasingly correlated damage culminating in a large ``critical'' earthquake. Recent laboratory experiments indeed show that stressed rocks form electric batteries which can release their charge when a conducting path closes the equivalent electric circuit. We conjecture that the intermittent and erratic occurrences of EM signals are a consequence of the progressive build-up of the battery charges in the Earth crust and their erratic release when crack networks are percolating throughout the stressed rock volumes, providing a conductive pathway for the battery currents to discharge. EM signals are thus expected close to the rupture, either slightly before or after, that is, when percolation is most favored.

F. Freund; D. Sornette

2006-03-24

181

Tuned analog network  

NASA Technical Reports Server (NTRS)

A noninverting, direct current amplifier stage is cascaded into an integrator stage to form a two stage tuned network with a single input junction common to both stages. The network provides independent adjustment of center frequency, bandwidth and voltage gain. The insertion of a positive feedback loop between the stages provides a very narrow bandwidth network. The addition of back to back zener diodes between the common input node and ground converts the network into an oscillator.

Kleinberg, L. L. (inventor)

1983-01-01

182

Local area networking: Ames centerwide network  

NASA Technical Reports Server (NTRS)

A computer network can benefit the user by making his/her work quicker and easier. A computer network is made up of seven different layers with the lowest being the hardware, the top being the user, and the middle being the software. These layers are discussed.

Price, Edwin

1988-01-01

183

Telecommunications network management laboratory  

Microsoft Academic Search

This work discusses network management laboratory design and implementation at the University of Wollongong in the School of Electrical, Computer and Telecommunications Engineering in years of 2002 and 2003 for a final year specialisation subject called telecommunication network management for telecommunications engineering students. The design and implementation included that of a network management GUI incorporating the fundamental aspects and functionality

I. Raad; P. Vial

2004-01-01

184

Covert Communication Networks  

E-print Network

of resilient covert communications networks that: (1) minimize the impact on the network in the event of a subverted node; and (2) maximize the connectivity of the survivor network with the removal of the subverted node and its closed neighborhood. We analyze...

Nix, Timothy Glen

2013-08-02

185

CULTIVATING NETWORKS: IMPLEMENTING SURGICAL  

E-print Network

i CULTIVATING NETWORKS: IMPLEMENTING SURGICAL TELEMEDICINE Margunn Aanestad THE INTERVENTIONAL OF MATHEMATICS AND NATURAL SCIENCES, UNIVERSITY OF OSLO #12;ii CULTIVATING NETWORKS: IMPLEMENTING SURGICAL single site use: the challenges of growing networks 38 6.2.2 Micro- and macro-level design in use 39 6

Sahay, Sundeep

186

Networking Computers Schoolwide.  

ERIC Educational Resources Information Center

Discusses the planning that is needed to effectively network school computers. Topics addressed include advantages of networking, including electronic mail, cost effectiveness, and time savings; use by students and teachers; wiring systems; network configurations; and use by library/media centers. (LRW)

Lipman, Art

1994-01-01

187

Equilibrium games in networks  

NASA Astrophysics Data System (ADS)

It seems a universal phenomenon of networks that the attacks on a small number of nodes by an adversary player Alice may generate a global cascading failure of the networks. It has been shown (Li et al., 2013) that classic scale-free networks (Barabási and Albert, 1999, Barabási, 2009) are insecure against attacks of as small as O(logn) many nodes. This poses a natural and fundamental question: Can we introduce a second player Bob to prevent Alice from global cascading failure of the networks? We proposed a game in networks. We say that a network has an equilibrium game if the second player Bob has a strategy to balance the cascading influence of attacks by the adversary player Alice. It was shown that networks of the preferential attachment model (Barabási and Albert, 1999) fail to have equilibrium games, that random graphs of the Erdös-Rényi model (Erdös and Rényi, 1959, Erdös and Rényi, 1960) have, for which randomness is the mechanism, and that homophyly networks (Li et al., 2013) have equilibrium games, for which homophyly and preferential attachment are the underlying mechanisms. We found that some real networks have equilibrium games, but most real networks fail to have. We anticipate that our results lead to an interesting new direction of network theory, that is, equilibrium games in networks.

Li, Angsheng; Zhang, Xiaohui; Pan, Yicheng; Peng, Pan

2014-12-01

188

Smart networks for control  

Microsoft Academic Search

Control networks move small packets of data to a large set of nodes, so as to integrate and automate everything from home appliances to entire factories. This is due to the use of embedded microprocessors. The author discusses the control net architecture, network topology and the fast response of the network

R. S. Raji

1994-01-01

189

Introduction to Telecommunications Networks  

NSDL National Science Digital Library

This page from Delmar Learning provides more information about the book "Introduction To Telecommunications Networks" by Gordon F. Snyder of the ICT Center. The book includes information on the history of the public switched telephone network, electronics, public and private telecommunications networks and other related information. Users may order the book via this website. A link is also provided to request a review copy.

Snyder, Gordon F.

2012-10-22

190

Aeronautical ad hoc networks  

Microsoft Academic Search

There has been an enormous growth in mobile ad hoc networks (MANETs) in land based small to medium size networks with relatively strict power and resources. In this paper the concept of ad hoc networking between aircraft is introduced, which can be considered as a novel approach in increasing the data rate and practicality of future in-flight broadband Internet access.

Ehssan Sakhaee; Abbas Jamalipour; Nei Kato

2006-01-01

191

Metallic nanowire networks  

DOEpatents

A metallic nanowire network synthesized using chemical reduction of a metal ion source by a reducing agent in the presence of a soft template comprising a tubular inverse micellar network. The network of interconnected polycrystalline nanowires has a very high surface-area/volume ratio, which makes it highly suitable for use in catalytic applications.

Song, Yujiang; Shelnutt, John A.

2012-11-06

192

Computational Verb Neural Networks  

Microsoft Academic Search

When any attribute value in a conventional neural network is verbified, the result is a computational verb neural network(VNN). We can verbify inputs, outputs, biases, weights and many other attributes of conventional neural networks. In this paper, we reported two types of VNNs. The first one consists of computational verb inputs and numerical output. The second one consists of computational

Tao Yang

2007-01-01

193

Appalachia Community Cancer Network  

Cancer.gov

A multidisciplinary team of collaborators from academic institutions and communities in Appalachian regions of Kentucky, West Virginia, Ohio, Pennsylvania, New York, Maryland, and Virginia are proposing to build on a strong foundation of previous activity of the Appalachia Cancer Network (ACN), an NCI-funded Special Populations Network, and develop the Appalachia Community Cancer Network (ACCN).

194

Multimedia Networks: Mission Impossible?  

ERIC Educational Resources Information Center

Running multimedia on a network, often difficult because of the memory and processing power required, is becoming easier thanks to new protocols and products. Those developing network design criteria may wish to consider making use of Fast Ethernet, Asynchronous Transfer Method (ATM), switches, "fat pipes", additional network segmentation, and…

Weiss, Andrew M.

1996-01-01

195

Internet2 Network  

NSDL National Science Digital Library

Internet2 provides the U.S. research and education community with a dynamic, innovative and cost-effective hybrid optical and packet network. The network was designed to provide next-generation production services as well as a platform for the development of new networking ideas and protocols.

2009-08-14

196

A Network Security Monitor  

Microsoft Academic Search

This study concentrates on the security-related issues in a single broadcast LAN (local area network) such as Ethernet. The authors formalize various possible network attacks. Their basic strategy is to develop profiles of usage of network resources and then compare current usage patterns with the historical profile to determine possible security violations. Thus, the work is similar to the host-based

L. Todd Herberlein; Gihan V. Dias; Karl N. Levitt; Biswanath Mukherjee; Jeff Wood; David Wolber

1990-01-01

197

Resilience in multilayer networks  

Microsoft Academic Search

. The integration of different technologies such as ATM, SDH and WDMin future multi-layer transport networks requires a better coordination between theindividual network layers. Especially in the area of network survivability, it is feltthat much can be gained by a better coordination and integration of the healingactions taken by the different layers in the event of failures. We present aframework

Piet Demeester; Michael Gryseels; A. Autenrieth; C. Brianza; L. Castagna; G. Signorelli; R. Clemenfe; M. Ravera; A. Jajszczyk; D. Janukowicz; K. Van Doorselaere; Y. Harada

1999-01-01

198

Quantifying network heterogeneity.  

PubMed

Despite degree distributions give some insights about how heterogeneous a network is, they fail in giving a unique quantitative characterization of network heterogeneity. This is particularly the case when several different distributions fit for the same network, when the number of data points is very scarce due to network size, or when we have to compare two networks with completely different degree distributions. Here we propose a unique characterization of network heterogeneity based on the difference of functions of node degrees for all pairs of linked nodes. We show that this heterogeneity index can be expressed as a quadratic form of the Laplacian matrix of the network, which allows a spectral representation of network heterogeneity. We give bounds for this index, which is equal to zero for any regular network and equal to one only for star graphs. Using it we study random networks showing that those generated by the Erdös-Rényi algorithm have zero heterogeneity, and those generated by the preferential attachment method of Barabási and Albert display only 11% of the heterogeneity of a star graph. We finally study 52 real-world networks and we found that they display a large variety of heterogeneities. We also show that a classification system based on degree distributions does not reflect the heterogeneity properties of real-world networks. PMID:21230700

Estrada, Ernesto

2010-12-01

199

Emergent Network Defense  

ERIC Educational Resources Information Center

The research problem that inspired this effort is the challenge of managing the security of systems in large-scale heterogeneous networked environments. Human intervention is slow and limited: humans operate at much slower speeds than networked computer communications and there are few humans associated with each network. Enabling each node in the…

Crane, Earl Newell

2013-01-01

200

ad hoc networks.\\  

Microsoft Academic Search

Purpose – Mobile ad hoc networks rely on cooperation to perform essential network mechanisms such as routing. Therefore, network performance depends to a great extent on giving participating nodes an incentive for cooperation. The level of trust among nodes is the most frequently used parameter for promoting cooperation in distributed systems. There are different models for representing trust, each of

Marcela Mejia; Néstor M. Peña; Jose L. Muñoz; Oscar Esparza

2009-01-01

201

The Shared Information Network.  

ERIC Educational Resources Information Center

Discusses the use of shared information networks within organizations to decrease information hoarding and maximize operating efficiencies. Network development issues discussed include choosing the department responsible for development, selecting information to be included in the network, designing the information format, distribution strategies,…

Stanat, Ruth

1990-01-01

202

The Network Classroom.  

ERIC Educational Resources Information Center

Discussion of the role of new computer communications technologies in education focuses on modern networking systems, including fiber distributed data interface and Integrated Services Digital Network; strategies for implementing networked-based communication; and public online information resources for the classroom, including Bitnet, Internet,…

Maule, R. William

1993-01-01

203

Aspects of Network Design  

Microsoft Academic Search

Abstract In this dissertation we study two problems from the area of network design. The flrst part discusses the multicommodity buy-at-bulk network design problem, a problem that occurs naturally in the design of telecommunication and transportation networks. We are given an underlying graph and associated with each edge of the graph, a cost function that represents the price of routing

Adriana Karagiozova

2007-01-01

204

Networks: 4.0  

NSDL National Science Digital Library

These five activities give students practice in interpreting and creating network representations that organize information and relate connectedness and other metrics such as time and distance. Among the types of networks studied are transport distances, family trees, events tree diagrams, and factor networks. Teaching suggestions, links to materials, and progress indicators are included.

2010-07-29

205

Spanish Museum Libraries Network.  

ERIC Educational Resources Information Center

This paper describes the creation of an automated network of museum libraries in Spain. The only way in which the specialized libraries in the world today can continue to be active and to offer valid information is to automate the service they offer, and create network libraries with cooperative plans. The network can be configured with different…

Lopez de Prado, Rosario

206

Towards global network positioning  

Microsoft Academic Search

We propose a new approach to predict Internet network distance called Global Network Positioning (GNP). This approach models the Internet as a geometric space and distributedly computes geometric coordinates to characterize the positions of hosts in the Internet. By conducting Internet experiments, we show that the geometric distances implied by the GNP hosts coordinates can accurately predict the Internet network

T. S. Eugene Ng; Hui Zhang

2001-01-01

207

Bayesian Networks without Tears  

Microsoft Academic Search

Over the last few years, a method of reasoning using probabilities, vari- ously called belief networks, Bayesian networks, knowl- edge maps, proba- bilistic causal networks, and so on, has become popular within the AI proba- bility and uncertain- ty community. This method is best sum- marized in Judea Pearl's (1988) book, but the ideas are a product of many hands.

Eugene Charniak

1991-01-01

208

Network Characterization Service (NCS)  

SciTech Connect

Distributed applications require information to effectively utilize the network. Some of the information they require is the current and maximum bandwidth, current and minimum latency, bottlenecks, burst frequency, and congestion extent. This type of information allows applications to determine parameters like optimal TCP buffer size. In this paper, we present a cooperative information-gathering tool called the network characterization service (NCS). NCS runs in user space and is used to acquire network information. Its protocol is designed for scalable and distributed deployment, similar to DNS. Its algorithms provide efficient, speedy and accurate detection of bottlenecks, especially dynamic bottlenecks. On current and future networks, dynamic bottlenecks do and will affect network performance dramatically.

Jin, Guojun; Yang, George; Crowley, Brian; Agarwal, Deborah

2001-06-06

209

Networks Technology Conference  

NASA Technical Reports Server (NTRS)

The papers included in these proceedings represent the most interesting and current topics being pursued by personnel at GSFC's Networks Division and supporting contractors involved in Space, Ground, and Deep Space Network (DSN) technical work. Although 29 papers are represented in the proceedings, only 12 were presented at the conference because of space and time limitations. The proceedings are organized according to five principal technical areas of interest to the Networks Division: Project Management; Network Operations; Network Control, Scheduling, and Monitoring; Modeling and Simulation; and Telecommunications Engineering.

Tasaki, Keiji K. (editor)

1993-01-01

210

An algebraic approach to network coding  

Microsoft Academic Search

We take a new look at the issue of network capacity. It is shown that network coding is an essential ingredient in achieving the capacity of a network. Building on recent work by Li et al., who examined the network capacity of multicast networks, we extend the network coding framework to arbitrary networks and robust networking. For networks which are

Ralf Koetter; Muriel Médard

2003-01-01

211

Doing Shakespeare: "Yo! A Hit! A Very Palpable Hit!"  

ERIC Educational Resources Information Center

Describes the realities of current state of the teaching of William Shakespeare in U.S. schools. Compares these realities with the philosophy of teaching of the Folger Shakespeare Library in Washington, DC. Shows how the Folger Library's education program resonates with their proclaimed philosophy. (HB)

O'Brien, Peggy

1993-01-01

212

yoU Totally Aware Phone:...............817-272-3381  

E-print Network

, what makes you think they won't cheat you? #12;Double Stack--or PMA is a designer analog of meth-amphetamine lasts only an hour. Ice--A smokable form of recrystallized meth- amphetamine with a similar effect hours. Cat--is a designer analog of meth- amphetamine which has been brought into the country from

Texas at Arlington, University of

213

Network topology analysis.  

SciTech Connect

Emerging high-bandwidth, low-latency network technology has made network-based architectures both feasible and potentially desirable for use in satellite payload architectures. The selection of network topology is a critical component when developing these multi-node or multi-point architectures. This study examines network topologies and their effect on overall network performance. Numerous topologies were reviewed against a number of performance, reliability, and cost metrics. This document identifies a handful of good network topologies for satellite applications and the metrics used to justify them as such. Since often multiple topologies will meet the requirements of the satellite payload architecture under development, the choice of network topology is not easy, and in the end the choice of topology is influenced by both the design characteristics and requirements of the overall system and the experience of the developer.

Kalb, Jeffrey L.; Lee, David S.

2008-01-01

214

Percolation on sparse networks.  

PubMed

We study percolation on networks, which is used as a model of the resilience of networked systems such as the Internet to attack or failure and as a simple model of the spread of disease over human contact networks. We reformulate percolation as a message passing process and demonstrate how the resulting equations can be used to calculate, among other things, the size of the percolating cluster and the average cluster size. The calculations are exact for sparse networks when the number of short loops in the network is small, but even on networks with many short loops we find them to be highly accurate when compared with direct numerical simulations. By considering the fixed points of the message passing process, we also show that the percolation threshold on a network with few loops is given by the inverse of the leading eigenvalue of the so-called nonbacktracking matrix. PMID:25432059

Karrer, Brian; Newman, M E J; Zdeborová, Lenka

2014-11-14

215

Mutually connected component of networks of networks with replica nodes  

NASA Astrophysics Data System (ADS)

We describe the emergence of the giant mutually connected component in networks of networks in which each node has a single replica node in any layer and can be interdependent only on its replica nodes in the interdependent layers. We prove that if, in these networks, all the nodes of one network (layer) are interdependent on the nodes of the same other interconnected layer, then, remarkably, the mutually connected component does not depend on the topology of the network of networks. This component coincides with the mutual component of the fully connected network of networks constructed from the same set of layers, i.e., a multiplex network.

Bianconi, Ginestra; Dorogovtsev, Sergey N.; Mendes, José F. F.

2015-01-01

216

EFFICIENT NETWORK CAMOUFLAGING IN WIRELESS NETWORKS A Dissertation  

E-print Network

EFFICIENT NETWORK CAMOUFLAGING IN WIRELESS NETWORKS A Dissertation by SHU JIANG Submitted CAMOUFLAGING IN WIRELESS NETWORKS A Dissertation by SHU JIANG Submitted to the Office of Graduate Studies ABSTRACT Efficient Network Camouflaging in Wireless Networks. (December 2005) Shu Jiang, B.E., University

Vaidya, Nitin

217

8: Network Security 8-1 Network Security Overview  

E-print Network

"confidentiality" authentication message integrity security in practice: security in application (eg. Email8: Network Security 8-1 Network Security Overview Computer Networking: A Top Down Approach , Jim Kurose, Keith Ross Based on: Chapter 8 #12;8: Network Security 8-2 Chapter 8: Network Security Chapter

Lu, Enyue "Annie"

218

Serial Network Flow Monitor  

NASA Technical Reports Server (NTRS)

Using a commercial software CD and minimal up-mass, SNFM monitors the Payload local area network (LAN) to analyze and troubleshoot LAN data traffic. Validating LAN traffic models may allow for faster and more reliable computer networks to sustain systems and science on future space missions. Research Summary: This experiment studies the function of the computer network onboard the ISS. On-orbit packet statistics are captured and used to validate ground based medium rate data link models and enhance the way that the local area network (LAN) is monitored. This information will allow monitoring and improvement in the data transfer capabilities of on-orbit computer networks. The Serial Network Flow Monitor (SNFM) experiment attempts to characterize the network equivalent of traffic jams on board ISS. The SNFM team is able to specifically target historical problem areas including the SAMS (Space Acceleration Measurement System) communication issues, data transmissions from the ISS to the ground teams, and multiple users on the network at the same time. By looking at how various users interact with each other on the network, conflicts can be identified and work can begin on solutions. SNFM is comprised of a commercial off the shelf software package that monitors packet traffic through the payload Ethernet LANs (local area networks) on board ISS.

Robinson, Julie A.; Tate-Brown, Judy M.

2009-01-01

219

A network security monitor  

SciTech Connect

The study of security in computer networks is a rapidly growing area of interest because of the proliferation of networks and the paucity of security measures in most current networks. Since most networks consist of a collection of inter-connected local area networks (LANs), this paper concentrates on the security-related issues in a single broadcast LAN such as Ethernet. Specifically, we formalize various possible network attacks and outline methods of detecting them. Our basic strategy is to develop profiles of usage of network resources and then compare current usage patterns with the historical profile to determine possible security violations. Thus, our work is similar to the host-based intrusion-detection systems such as SRI's IDES. Different from such systems, however, is our use of a hierarchical model to refine the focus of the intrusion-detection mechanism. We also report on the development of our experimental LAN monitor currently under implementation. Several network attacks have been simulated and results on how the monitor has been able to detect these attacks are also analyzed. Initial results demonstrate that many network attacks are detectable with our monitor, although it can surely be defeated. Current work is focusing on the integration of network monitoring with host-based techniques. 20 refs., 2 figs.

Heberlein, L.T.; Dias, G.V.; Levitt, K.N.; Mukherjee, B.; Wood, J.; Wolber, D. (California Univ., Davis, CA (USA). Dept. of Electrical Engineering and Computer Science)

1989-11-01

220

A practical gated expert network  

Microsoft Academic Search

Difficulties in training multilayer networks for strongly nonlinear problems has led some researchers to propose the gated expert networks. The idea is based on having several local “expert networks”, where each learns a particular region of the input space. A “gating network” combines the outputs of the expert networks to produce the final output. We propose a practical gated expert

A. Atiya; R. Aiyad; S. Shaheen

1998-01-01

221

An approach for modeling vulnerability of the network of networks  

NASA Astrophysics Data System (ADS)

In this paper, a framework is given to model the network of networks and to investigate the vulnerability of the network of networks subjected to failures. Because there are several redundant systems in infrastructure systems, the dependent intensity between two networks is introduced and adopted to discuss the vulnerability of the interdependent infrastructure networks subjected to failures. Shanghai electrified rail transit network is used to illustrate the feasibility and effectiveness of the proposed framework. Because the rail network is dependent on the power grid and communication network, the corresponding power grid and communication network are also included in this system. Meanwhile the failures to the power grid and communication network are utilized to investigate the vulnerability of the rail network. The results show that the rail network strongly depends on the power grid and weakly depends on the communication network, and the transport functionality loss of the rail network increases with the increase of dependent intensity. Meanwhile the highest betweenness node-based attack to the power grid and the largest degree node-based attack to the communication network can result in the most functionality losses to the rail network. Moreover, the functionality loss of the rail network has the smallest value when the tolerance parameter of the power grid equals 0.75 and the critical nodes of the power grid and communication network can be obtained by simulations.

Zhang, Jianhua; Song, Bo; Zhang, Zhaojun; Liu, Haikuan

2014-10-01

222

Reconfigureable network node  

DOEpatents

Nodes in a network having a plurality of nodes establish communication links with other nodes using available transmission media, as the ability to establish such links becomes available and desirable. The nodes predict when existing communications links will fail, become overloaded or otherwise degrade network effectiveness and act to establish substitute or additional links before the node's ability to communicate with the other nodes on the network is adversely affected. A node stores network topology information and programmed link establishment rules and criteria. The node evaluates characteristics that predict existing links with other nodes becoming unavailable or degraded. The node then determines whether it can form a communication link with a substitute node, in order to maintain connectivity with the network. When changing its communication links, a node broadcasts that information to the network. Other nodes update their stored topology information and consider the updated topology when establishing new communications links for themselves.

Vanderveen, Keith B. (Tracy, CA); Talbot, Edward B. (Livermore, CA); Mayer, Laurence E. (Davis, CA)

2008-04-08

223

Compressive Network Analysis  

PubMed Central

Modern data acquisition routinely produces massive amounts of network data. Though many methods and models have been proposed to analyze such data, the research of network data is largely disconnected with the classical theory of statistical learning and signal processing. In this paper, we present a new framework for modeling network data, which connects two seemingly different areas: network data analysis and compressed sensing. From a nonparametric perspective, we model an observed network using a large dictionary. In particular, we consider the network clique detection problem and show connections between our formulation with a new algebraic tool, namely Randon basis pursuit in homogeneous spaces. Such a connection allows us to identify rigorous recovery conditions for clique detection problems. Though this paper is mainly conceptual, we also develop practical approximation algorithms for solving empirical problems and demonstrate their usefulness on real-world datasets.

Jiang, Xiaoye; Yao, Yuan; Liu, Han; Guibas, Leonidas

2014-01-01

224

Reconstructing Regulatory Network Transitions  

PubMed Central

Cellular responses often involve a transition of cells from one state to another. A transition from a stem cell to differentiated cell state, for example, may occur in response to gene expression changes induced by a transcription factor, or signaling cascades triggered by a hormone or pathogen. Regulatory networks are thought to control such cellular transitions. Thus, many researchers are interested in reconstructing regulatory networks, not only to gain a deeper understanding of cellular transitions, but also with the aim of using networks to predict and potentially manipulate cellular transitions and outcomes. In this review, we highlight approaches to the reconstruction of regulatory networks underlying cellular transitions, with special attention to transcriptional regulatory networks. We describe recent regulatory network reconstructions in a variety of organisms and discuss the success they share in identifying new regulatory components as well as shared relationships and phenotypic outcomes. PMID:21632251

Petricka, Jalean J.; Benfey, Philip N.

2011-01-01

225

MSAT network architecture  

NASA Technical Reports Server (NTRS)

The Mobile Satellite (MSAT) communications system will support mobile voice and data services using circuit switched and packet switched facilities with interconnection to the public switched telephone network and private networks. Control of the satellite network will reside in a Network Control System (NCS) which is being designed to be extremely flexible to provide for the operation of the system initially with one multi-beam satellite, but with capability to add additional satellites which may have other beam configurations. The architecture of the NCS is described. The signalling system must be capable of supporting the protocols for the assignment of circuits for mobile public telephone and private network calls as well as identifying packet data networks. The structure of a straw-man signalling system is discussed.

Davies, N. G.; Skerry, B.

1990-01-01

226

Networked Innovation in Innovation Networks: A Home Appliances Case Study  

NASA Astrophysics Data System (ADS)

Amongst different types of Collaborative Networked Organizations it is possible to highlight those created to develop and market product, process or business model innovation. In this type of innovation network, which has special characteristics, the challenge is to introduce effective networked innovation in the very same innovation network. This paper presents the main features of TALAI-SAREA © methodology that includes a reference model, a set of analysis tools and a method for implementing networked innovation in innovation networks.

Berasategi, Luis; Arana, Joseba; Castellano, Eduardo

227

From Photo Networks to Social Networks, Creation and Use of a Social Network Derived with Photos  

E-print Network

From Photo Networks to Social Networks, Creation and Use of a Social Network Derived with Photos and photos have received plenty of attention in the digital age. In this paper, we show how social photos that reveals social attributes. From this photo network, a social network is extracted that can help to build

Boyer, Edmond

228

Investigating the validity of current network analysis on static conglomerate networks by protein network stratification  

Microsoft Academic Search

BACKGROUND: A molecular network perspective forms the foundation of systems biology. A common practice in analyzing protein-protein interaction (PPI) networks is to perform network analysis on a conglomerate network that is an assembly of all available binary interactions in a given organism from diverse data sources. Recent studies on network dynamics suggested that this approach might have ignored the dynamic

Minlu Zhang; Long J. Lu

2010-01-01

229

The deep space network  

NASA Technical Reports Server (NTRS)

The objectives, functions, and organization of the Deep Space Network are summarized along with deep space station, ground communication, and network operations control capabilities. Mission support of ongoing planetary/interplanetary flight projects is discussed with emphasis on Viking orbiter radio frequency compatibility tests, the Pioneer Venus orbiter mission, and Helios-1 mission status and operations. Progress is also reported in tracking and data acquisition research and technology, network engineering, hardware and software implementation, and operations.

1975-01-01

230

Affinity driven social networks  

NASA Astrophysics Data System (ADS)

In this work we present a model for evolving networks, where the driven force is related to the social affinity between individuals of a population. In the model, a set of individuals initially arranged on a regular ordered network and thus linked with their closest neighbors are allowed to rearrange their connections according to a dynamics closely related to that of the stable marriage problem. We show that the behavior of some topological properties of the resulting networks follows a non trivial pattern.

Ruyú, B.; Kuperman, M. N.

2007-04-01

231

Processes on Complex Networks  

NSDL National Science Digital Library

Building on their understanding of graphs, students are introduced to random processes on networks. They walk through an illustrative example to see how a random process can be used to represent the spread of an infectious disease, such as the flu, on a social network of students. This demonstrates how scientists and engineers use mathematics to model and simulate random processes on complex networks. Topics covered include random processes and modeling disease spread, specifically the SIR (susceptible, infectious, resistant) model.

2014-09-18

232

The Cartoon Network  

Microsoft Academic Search

Currently seen in 70 million U.S. homes and 145 countries around the world, Cartoon Network is Turner Broadcasting System, Inc.'s 24-hour, ad-supported cable service offering animated entertainment. Since its launch in 1992, Cartoon Network has remained one of cable's highest-rated offerings. Drawing from the world's largest cartoon library, Cartoon Network also showcases a number of unique and award-winning original ventures.

Alan D. Fletcher

2002-01-01

233

NASA Integrated Network COOP  

NASA Technical Reports Server (NTRS)

Natural disasters, terrorist attacks, civil unrest, and other events have the potential of disrupting mission-essential operations in any space communications network. NASA's Space Communications and Navigation office (SCaN) is in the process of studying options for integrating the three existing NASA network elements, the Deep Space Network, the Near Earth Network, and the Space Network, into a single integrated network with common services and interfaces. The need to maintain Continuity of Operations (COOP) after a disastrous event has a direct impact on the future network design and operations concepts. The SCaN Integrated Network will provide support to a variety of user missions. The missions have diverse requirements and include anything from earth based platforms to planetary missions and rovers. It is presumed that an integrated network, with common interfaces and processes, provides an inherent advantage to COOP in that multiple elements and networks can provide cross-support in a seamless manner. The results of trade studies support this assumption but also show that centralization as a means of achieving integration can result in single points of failure that must be mitigated. The cost to provide this mitigation can be substantial. In support of this effort, the team evaluated the current approaches to COOP, developed multiple potential approaches to COOP in a future integrated network, evaluated the interdependencies of the various approaches to the various network control and operations options, and did a best value assessment of the options. The paper will describe the trade space, the study methods, and results of the study.

Anderson, Michael L.; Wright, Nathaniel; Tai, Wallace

2012-01-01

234

Albuquerque Basin seismic network  

USGS Publications Warehouse

The U.S. Geological Survey has recently completed the installation of a seismic network around the Albuquerque Basin in New Mexico. The network consists of two seismometer arrays, a thirteen-station array monitoring an area of approximately 28,000 km 2 and an eight-element array monitoring the area immediately adjacent to the Albuquerque Seismological Laboratory. This report describes the instrumentation deployed in the network.

Jaksha, Lawrence H.; Locke, Jerry; Thompson, J.B.; Garcia, Alvin

1977-01-01

235

Autonomous Mobile Networks  

Microsoft Academic Search

Summary form only given, as follows. Autonomous mobile networks are distributed ad-hoc networks of nodes that can sense, actuate, compute and communicate with each other using point-to-point multi-hop communication. The nodes in such networks include static sensors, mobile sensors, robots, and humans. Such systems combine the most advanced concepts in perception, communication and control to create computational systems capable of

Daniela Rus

2004-01-01

236

Network problem threshold  

NASA Technical Reports Server (NTRS)

Network transmission errors such as collisions, CRC errors, misalignment, etc. are statistical in nature. Although errors can vary randomly, a high level of errors does indicate specific network problems, e.g. equipment failure. In this project, we have studied the random nature of collisions theoretically as well as by gathering statistics, and established a numerical threshold above which a network problem is indicated with high probability.

Gejji, Raghvendra, R.

1992-01-01

237

Survivable WDM Mesh Networks  

Microsoft Academic Search

Abstract, In a wavelength-division-muliplexing (WDM) optical network, the failure of network elements (e. g., fiber links and cross connects) may cause the failure of several optical channels, thereby leading to large data losses. This study examines different approaches to protect a mesh-based WDM optical network from such failures. These approaches are based on two survivability paradigms: 1) path protection\\/restoration and

S. Ramamurthy; Laxman Sahasrabuddhe; Biswanath Mukherjee

2003-01-01

238

Solving Playground Network Problems  

NSDL National Science Digital Library

In this activity, learners use cooperation and logical thinking to find solutions to network problems on the playground. Learners act both as computer routers, figuring out with each other how to effectively get data to the place it's being sent, and as the actual data, because the learners travel various edges of a network to get to their destination or "home" point. Learners use geometry skills to determine the most efficient routes in the network.

Exploratorium

2010-01-01

239

Mobile Computing/Mobile Computing/Mobile Computing/Mobile Computing/ Mobile NetworksMobile NetworksMobile NetworksMobile Networks  

E-print Network

Network Protocols for Wired Network: EthernetNetwork: EthernetNetwork: EthernetNetwork: Ethernet Solomon's book addresses? Does it have two Ethernet addresses? What are differences between UDP and TCP? #12;3 Contents IP Optimization Current Topics 4 Network Protocols for WiredNetwork Protocols for WiredNetwork Protocols for Wired

Yu, Chansu

240

Closeness Possible through Computer Networking.  

ERIC Educational Resources Information Center

Points out the benefits of computer networking for scholastic journalism. Discusses three systems currently offering networking possibilities for publications: the Student Press Information Network; the Youth Communication Service; and the Dow Jones Newspaper Fund's electronic mail system. (MS)

Dodd, Julie E.

1989-01-01

241

American Samoa Community Cancer Network  

Cancer.gov

American Samoa Community Cancer Network  Back to CRCHD Ongoing Research CNP Project Listing American Samoa Community Cancer Network CNP Pilot Projects American Samoa Community Cancer Network PRINCIPAL INVESTIGATOR: Victor T. Williams Tofaeono,

242

Topics in neural networks  

SciTech Connect

Some aspects of the behavior of several neural networks are considered. The original Hopfield Associative Memory (HAM) is examined, and a lower bound on the number of spurious minima is derived when the stored memories are orthogonal. Two locally interconnected variations of the basic HAM network are proposed in which the maximum distance between two neurons that can be connected is upper bounded by B. It is shown that for such locally interconnected networks containing N neurons, if B/N {yields} 0 as N {yields} {infinity} then the capacity of the network is determined by B and is independent of N. A macroscopic-analysis technique first proposed by Amari for networks with random, nonsymmetric connection weights is modified to show that HAMs must have either one or two macroscopic stable states. The analysis and simulations show that the macroscopic behavior of networks with symmetric and nonsymmetric connections are qualitatively similar. A new class of neural networks derived from the trellis-graph representation of a convolutional code is proposed. Such a network can be viewed as a collection of winner-take-all networks interconnected to reflect the structure of the trellis graph.

Petsche, T.

1988-01-01

243

Competing edge networks  

NASA Astrophysics Data System (ADS)

We introduce a model for a pair of nonlinear evolving networks, defined over a common set of vertices, subject to edgewise competition. Each network may grow new edges spontaneously or through triad closure. Both networks inhibit the other's growth and encourage the other's demise. These nonlinear stochastic competition equations yield to a mean field analysis resulting in a nonlinear deterministic system. There may be multiple equilibria; and bifurcations of different types are shown to occur within a reduced parameter space. This situation models competitive communication networks such as BlackBerry Messenger displacing SMS; or instant messaging displacing emails.

Parsons, Mark; Grindrod, Peter

2012-06-01

244

Mixing navigation on networks  

NASA Astrophysics Data System (ADS)

In this article, we propose a mixing navigation mechanism, which interpolates between random-walk and shortest-path protocol. The navigation efficiency can be remarkably enhanced via a few routers. Some advanced strategies are also designed: For non-geographical scale-free networks, the targeted strategy with a tiny fraction of routers can guarantee an efficient navigation with low and stable delivery time almost independent of network size. For geographical localized networks, the clustering strategy can simultaneously increase efficiency and reduce the communication cost. The present mixing navigation mechanism is of significance especially for information organization of wireless sensor networks and distributed autonomous robotic systems.

Zhou, Tao

2008-05-01

245

Celestial data routing network  

NASA Astrophysics Data System (ADS)

Imagine that information processing human-machine network is threatened in a particular part of the world. Suppose that an anticipated threat of physical attacks could lead to disruption of telecommunications network management infrastructure and access capabilities for small geographically distributed groups engaged in collaborative operations. Suppose that small group of astronauts are exploring the solar planet and need to quickly configure orbital information network to support their collaborative work and local communications. The critical need in both scenarios would be a set of low-cost means of small team celestial networking. To the geographically distributed mobile collaborating groups such means would allow to maintain collaborative multipoint work, set up orbital local area network, and provide orbital intranet communications. This would be accomplished by dynamically assembling the network enabling infrastructure of the small satellite based router, satellite based Codec, and set of satellite based intelligent management agents. Cooperating single function pico satellites, acting as agents and personal switching devices together would represent self-organizing intelligent orbital network of cooperating mobile management nodes. Cooperative behavior of the pico satellite based agents would be achieved by comprising a small orbital artificial neural network capable of learning and restructing the networking resources in response to the anticipated threat.

Bordetsky, Alex

2000-11-01

246

Learn More About Networking  

NSDL National Science Digital Library

These are some interesting sites that will help you to understand networking and how it can benefit you. These sites contain sound so you may want to wear headphones if you are in a classroom. Learn how the internet began and the basics of the www. Learn why a network is useful. Jans network contains the important concepts of networking, Work through section 7 to learn about different types of connections, transmissions, media, and configurations. Then take the quiz at the end to see how ...

Watts, Mrs.

2007-10-12

247

Tangible Social Network System.  

E-print Network

?? Tangible social network system is a home-based communication solution specifically designed for elders. Former researches indicate that insufficient communication among elders cause several challenges… (more)

Mannapperuma, Chanaka

2010-01-01

248

Mission Critical Networking  

SciTech Connect

Mission-Critical Networking (MCN) refers to networking for application domains where life or livelihood may be at risk. Typical application domains for MCN include critical infrastructure protection and operation, emergency and crisis intervention, healthcare services, and military operations. Such networking is essential for safety, security and economic vitality in our complex world characterized by uncertainty, heterogeneity, emergent behaviors, and the need for reliable and timely response. MCN comprise networking technology, infrastructures and services that may alleviate the risk and directly enable and enhance connectivity for mission-critical information exchange among diverse, widely dispersed, mobile users.

Eltoweissy, Mohamed Y.; Du, David H.C.; Gerla, Mario; Giordano, Silvia; Gouda, Mohamed; Schulzrinne, Henning; Youssef, Moustafa

2010-06-01

249

Fault localization in backbone networks  

E-print Network

B. Gruschke. Integrated event management: Event correlationnetwork event correlation. In Integrated Network Managementevent correlation. In Fourth International Symposium on Integrated Network Management,

Kompella, Ramana Rao

2007-01-01

250

Avoiding catastrophic failure in correlated networks of networks  

NASA Astrophysics Data System (ADS)

Networks in nature do not act in isolation, but instead exchange information and depend on one another to function properly. Theory has shown that connecting random networks may very easily result in abrupt failures. This finding reveals an intriguing paradox: if natural systems organize in interconnected networks, how can they be so stable? Here we provide a solution to this conundrum, showing that the stability of a system of networks relies on the relation between the internal structure of a network and its pattern of connections to other networks. Specifically, we demonstrate that if interconnections are provided by network hubs, and the connections between networks are moderately convergent, the system of networks is stable and robust to failure. We test this theoretical prediction on two independent experiments of functional brain networks (in task and resting states), which show that brain networks are connected with a topology that maximizes stability according to the theory.

Reis, Saulo D. S.; Hu, Yanqing; Babino, Andrés; Andrade, José S., Jr.; Canals, Santiago; Sigman, Mariano; Makse, Hernán A.

2014-10-01

251

Network of Networks and the Climate System  

NASA Astrophysics Data System (ADS)

Network of networks is a new direction in complex systems science. One can find such networks in various fields, such as infrastructure (power grids etc.), human brain or Earth system. Basic properties and new characteristics, such as cross-degree, or cross-betweenness will be discussed. This allows us to quantify the structural role of single vertices or whole sub-networks with respect to the interaction of a pair of subnetworks on local, mesoscopic, and global topological scales. Next, we consider an inverse problem: Is there a backbone-like structure underlying the climate system? For this we propose a method to reconstruct and analyze a complex network from data generated by a spatio-temporal dynamical system. This technique is then applied to 3-dimensional data of the climate system. We interpret different heights in the atmosphere as different networks and the whole as a network of networks. This approach enables us to uncover relations to global circulation patterns in oceans and atmosphere. The global scale view on climate networks offers promising new perspectives for detecting dynamical structures based on nonlinear physical processes in the climate system. This concept is applied to Indian Monsoon data in order to characterize the regional occurrence of strong rain events and its impact on predictability. References: Arenas, A., A. Diaz-Guilera, J. Kurths, Y. Moreno, and C. Zhou, Phys. Reports 2008, 469, 93. Donges, J., Y. Zou, N. Marwan, and J. Kurths, Europhys. Lett. 2009, 87, 48007. Donner, R., Y. Zou, J. Donges, N. Marwan, and J. Kurths, Phys. Rev. E 2010, 81, 015101(R ). Mokhov, I. I., D. A. Smirnov, P. I. Nakonechny, S. S. Kozlenko, E. P. Seleznev, and J. Kurths, Geophys. Res. Lett. 2011, 38, L00F04. Malik, N., B. Bookhagen, N. Marwan, and J. Kurths, Climate Dynamics, 2012, 39, 971. Donges, J., H. Schultz, N. Marwan, Y. Zou, J. Kurths, Eur. J. Phys. B 2011, 84, 635-651. Donges, J., R. Donner, M. Trauth, N. Marwan, H.J. Schellnhuber, and J. Kurths, PNAS 2011, 108, 20422-20427. Runge, J. , J. Heitzig, V. Petoukhov, J. Kurths, Phys. Rev. Lett. 2012, 108, 258701.

Kurths, Jürgen; Boers, Niklas; Bookhagen, Bodo; Donges, Jonathan; Donner, Reik; Malik, Nishant; Marwan, Norbert; Stolbova, Veronika

2013-04-01

252

A Network Synthesis Model for Generating Protein Interaction Network Families  

PubMed Central

In this work, we introduce a novel network synthesis model that can generate families of evolutionarily related synthetic protein–protein interaction (PPI) networks. Given an ancestral network, the proposed model generates the network family according to a hypothetical phylogenetic tree, where the descendant networks are obtained through duplication and divergence of their ancestors, followed by network growth using network evolution models. We demonstrate that this network synthesis model can effectively create synthetic networks whose internal and cross-network properties closely resemble those of real PPI networks. The proposed model can serve as an effective framework for generating comprehensive benchmark datasets that can be used for reliable performance assessment of comparative network analysis algorithms. Using this model, we constructed a large-scale network alignment benchmark, called NAPAbench, and evaluated the performance of several representative network alignment algorithms. Our analysis clearly shows the relative performance of the leading network algorithms, with their respective advantages and disadvantages. The algorithm and source code of the network synthesis model and the network alignment benchmark NAPAbench are publicly available at http://www.ece.tamu.edu/bjyoon/NAPAbench/. PMID:22912671

Sahraeian, Sayed Mohammad Ebrahim; Yoon, Byung-Jun

2012-01-01

253

Receding Horizon Networked Control  

Microsoft Academic Search

This paper deals with the design of control systems over lossy networks. A network is assumed to exist between the sensor and the controller and between the latter and the actuator. Packets are dropped according to a Bernoulli independent process, with ? and \\

Vijay Gupta; Bruno Sinopoli; Sachin Adlakha; Andrea Goldsmith; Richard Murray

2006-01-01

254

Social networking sites.  

PubMed

In this bimonthly series, the author examines how nurse educators can use the Internet and Web-based computer technologies such as search, communication, and collaborative writing tools, social networking and social bookmarking sites, virtual worlds, and Web-based teaching and learning programs. This article describes social networking Web sites and techniques to increase their safe use. PMID:20173583

Wink, Diane M

2010-01-01

255

K-12 Computer Networking.  

ERIC Educational Resources Information Center

The "ERIC Review" is published three times a year and announces research results, publications, and new programs relevant to each issue's theme topic. This issue explores computer networking in elementary and secondary schools via two principal articles: "Plugging into the 'Net'" (Michael B. Eisenberg and Donald P. Ely); and "Computer Networks for…

ERIC Review, 1993

1993-01-01

256

Coherent optical CDMA networks  

Microsoft Academic Search

Recent work in optical code-division multiple access (CDMA) is reviewed, progressing from incoherent to coherent techniques. It is shown that under appropriate conditions, coherent CDMA can in principle rival wavelength-division multiplexing (WDM) in terms of aggregate network throughput. Furthermore, it is shown that at high data rates, some of the components for WDM are coherent CDMA networks are nearly identical,

Michel E. Marhic

1993-01-01

257

Community Wireless Networks  

ERIC Educational Resources Information Center

With increasing frequency, communities are seeing the arrival of a new class of noncommercial broadband providers: community wireless networks (CWNs). Utilizing the same wireless technologies that many colleges and universities have used to create wireless networks on campus, CWNs are creating broadband access for free or at costs well below…

Feld, Harold

2005-01-01

258

Evolving neural networks  

Microsoft Academic Search

Neural networks are parallel processing structures that provide the capability to perform various pattern recognition tasks. A network is typically trained over a set of exemplars by adjusting the weights of the interconnections using a back propagation algorithm. This gradient search converges to locally optimal solutions which may be far removed from the global optimum. In this paper, evolutionary programming

D. B. Fogel; L. J. Fogel; V. W. Porto

1990-01-01

259

A Balanced Memory Network  

PubMed Central

A fundamental problem in neuroscience is understanding how working memory—the ability to store information at intermediate timescales, like tens of seconds—is implemented in realistic neuronal networks. The most likely candidate mechanism is the attractor network, and a great deal of effort has gone toward investigating it theoretically. Yet, despite almost a quarter century of intense work, attractor networks are not fully understood. In particular, there are still two unanswered questions. First, how is it that attractor networks exhibit irregular firing, as is observed experimentally during working memory tasks? And second, how many memories can be stored under biologically realistic conditions? Here we answer both questions by studying an attractor neural network in which inhibition and excitation balance each other. Using mean-field analysis, we derive a three-variable description of attractor networks. From this description it follows that irregular firing can exist only if the number of neurons involved in a memory is large. The same mean-field analysis also shows that the number of memories that can be stored in a network scales with the number of excitatory connections, a result that has been suggested for simple models but never shown for realistic ones. Both of these predictions are verified using simulations with large networks of spiking neurons. PMID:17845070

Roudi, Yasser; Latham, Peter E

2007-01-01

260

Wireless Sensors Network (Sensornet)  

NASA Technical Reports Server (NTRS)

The Wireless Sensor Network System presented in this paper provides a flexible reconfigurable architecture that could be used in a broad range of applications. It also provides a sensor network with increased reliability; decreased maintainability costs, and assured data availability by autonomously and automatically reconfiguring to overcome communication interferences.

Perotti, J.

2003-01-01

261

Wireless Sensor Networks Approach  

NASA Technical Reports Server (NTRS)

This viewgraph presentation provides information on hardware and software configurations for a network architecture for sensors. The hardware configuration uses a central station and remote stations. The software configuration uses the 'lost station' software algorithm. The presentation profiles a couple current examples of this network architecture in use.

Perotti, Jose M.

2003-01-01

262

The Community Networking Handbook.  

ERIC Educational Resources Information Center

This publication outlines the complete community networking process: planning, developing partnerships, funding, marketing, content, public access, and evaluation, and discusses the variety of roles that the local public library can play in this process. Chapter One, "The Importance of Community Networking," describes the importance of community…

Bajjaly, Stephen T.

263

Marketing action in networks  

Microsoft Academic Search

Purpose – The aim of this paper is to describe and explain how organizations develop and implement marketing action within their surrounding business networks. Design\\/methodology\\/approach – The paper is an empirical case study research that covered periods 1993 to 1998 and 2002 to 2003 in manufacturer-retailer networks in Germany. A conceptual model is developed and its applicability is illustrated. Findings

Stefanos Mouzas

2006-01-01

264

Developing network insight  

Microsoft Academic Search

A challenge facing organizations is that of amalgamating possibilities which do not exist in a transparent and concentrated form, but rather as dispersed individual cognitive ‘pictures’ perceived by managers embedded in business networks. Based on our research of business networks involving manufacturers of consumer goods, pharmaceutical companies, producers of semiconductors and telecommunication and utility service providers, we propose the concept

Stefanos Mouzas; Stephan Henneberg; Peter Naudé

2008-01-01

265

Home networks - getting there  

Microsoft Academic Search

The drivers for the next evolutionary step in home networking the technology, the market, and the consumer - are essentially in place. What is still needed to realize the promise of home networking are drivers such as open, complete solutions, clear business models, and an end-to-end infrastructure that offers valuable, integrated services to the home

S. Sharan

2002-01-01

266

Local Area Networks.  

ERIC Educational Resources Information Center

Discusses cabling that is needed in local area networks (LANs). Types of cables that may be selected are described, including twisted pair, coaxial cables (or ethernet), and fiber optics; network topologies, the manner in which the cables are laid out, are considered; and cable installation issues are discussed. (LRW)

Marks, Kenneth E.; Nielsen, Steven

1991-01-01

267

Energy Efficient Digital Networks  

E-print Network

Ethernet and process IP packets. Devices supporting other physical layers and protocolsEthernet Adaptive Link Rate (ALR): Analysis of a MAC Handshake Protocol.Ethernet RF Radio frequency RPS Rapid PHY selection SNE Small network equipment SNMP Simple network management protocol

Lanzisera, Steven

2014-01-01

268

Student Observation Network DVD  

NSDL National Science Digital Library

This DVD is meant to be given to educators after the 16 hour training on the Tracking a Solar Storm Module of NASA's Student Observation Network. It was created to be used as a resource for content about solar storms and a quick refresher of the modules available through the Student Observation Network.

2004-01-01

269

Miniaturized wireless sensor network  

Microsoft Academic Search

This paper addresses an overview of the wireless sensor networks. It is shown\\u000athat MEMS\\/NEMS technologies and SIP concept are well suited for advanced\\u000aarchitectures. It is also shown analog architectures have to be compatible with\\u000adigital signal techniques to develop smart network of microsystem.

Aubin Lecointre; Daniela Dragomirescu; David Dubuc; Grenier Katia; Pons Patrick; Hervé Aubert; A. Muller; Pascal Berthou; Thierry Gayraud; Robert Plana

2010-01-01

270

The deep space network  

NASA Technical Reports Server (NTRS)

The progress is reported of Deep Space Network (DSN) research in the following areas: (1) flight project support, (2) spacecraft/ground communications, (3) station control and operations technology, (4) network control and processing, and (5) deep space stations. A description of the DSN functions and facilities is included.

1974-01-01

271

Trees, networks, and hydrology  

Microsoft Academic Search

This paper reviews theoretical and observational material on form and function of natural networks appeared in somewhat disparate contexts from physics to biology, whose study is related to hydrologic research. Moving from the exact result that drainage network configurations minimizing total energy dissipation are stationary solutions of the general equation describing landscape evolution, we discuss the properties and the dynamic

Andrea Rinaldo; Jayanth R. Banavar; Amos Maritan

2006-01-01

272

Abstract -C networks, fuzzy  

E-print Network

Abstract - C networks, fuzzy networks and usefulness and applications. V technological re capable, includi Takagi-Sugano building blocks of fuzzy and ne] several applica concluded with chip. Fascination started in Kohonen uns backpropagatior staredrapid dew Neuro-fuzzy Systems and Their Applications Bogdan M

Wilamowski, Bogdan Maciej

273

Hubless satellite communications networks  

NASA Astrophysics Data System (ADS)

Frequency Comb Multiple Access (FCMA) is a new combined modulation and multiple access method which will allow cheap hubless Very Small Aperture Terminal (VSAT) networks to be constructed. Theoretical results show bandwidth efficiency and power efficiency improvements over other modulation and multiple access methods. Costs of the VSAT network are reduced dramatically since a hub station is not required.

Robinson, Peter Alan

1994-02-01

274

Superpositional Quantum Network Topologies  

Microsoft Academic Search

We introduce superposition-based quantum networks composed of (i) the classical perceptron model of multilayered, feedforward neural networks and (ii) the algebraic model of evolving reticular quantum structures as described in quantum gravity. The main feature of this model is moving from particular neural topologies to a quantum metastructure which embodies many differing topological patterns. Using quantum parallelism, training is possible

Christopher Altman; Jaroslaw Pykacz; Romàn R. Zapatrin

2004-01-01

275

Networks; Who, Why, How?  

ERIC Educational Resources Information Center

The May-June, 1975, issue of Wisconsin Library Bulletin contains articles about library cooperative programs and networks. Subjects covered include: library network planning and definitions of terms; views on the National Commission on Libraries and Information Science program by school, public, academic, and state librarians; the Midwest Library…

Wisconsin Library Bulletin, 1975

1975-01-01

276

Shallow water acoustic networks  

Microsoft Academic Search

Underwater acoustic networks are generally formed by acoustically connected ocean bottom sensor nodes, autonomous underwater vehicles (AUVs), and surface stations that serve as gateways and provide radio communication links to on-shore stations. The quality of service of such networks is limited by the low bandwidth of acoustic transmission channels, high latency resulting from the slow propagation of sound, and elevated

John G. Proakis; Ethem M. Sozer; Joseph A. Rice; M. Stojanovic

2001-01-01

277

Networked Teaching and Learning.  

ERIC Educational Resources Information Center

This theme issue on networked teaching and learning contains 11 articles written by teachers of English and language arts in Bread Loaf's primarily rural, teacher networks. Most of these narratives describe how teachers have taught writing and literature using online exchanges or teleconferencing involving students in different locations and grade…

Benson, Chris, Ed.

2002-01-01

278

Optimal Phase Oscillatory Network  

NASA Astrophysics Data System (ADS)

Important topics as preventive detection of epidemics, collective self-organization, information flow and systemic robustness in clusters are typical examples of processes that can be studied in the context of the theory of complex networks. It is an emerging theory in a field, which has recently attracted much interest, involving the synchronization of dynamical systems associated to nodes, or vertices, of the network. Studies have shown that synchronization in oscillatory networks depends not only on the individual dynamics of each element, but also on the combination of the topology of the connections as well as on the properties of the interactions of these elements. Moreover, the response of the network to small damages, caused at strategic points, can enhance the global performance of the whole network. In this presentation we explore an optimal phase oscillatory network altered by an additional term in the coupling function. The application to associative-memory network shows improvement on the correct information retrieval as well as increase of the storage capacity. The inclusion of some small deviations on the nodes, when solutions are attracted to a false state, results in additional enhancement of the performance of the associative-memory network.

Follmann, Rosangela

2013-03-01

279

Social Insect Networks  

NSDL National Science Digital Library

Social insect colonies have many of the properties of adaptive networks. The simple rules governing how local interactions among individuals translate into group behaviors are found across social groups, giving social insects the potential to have a profound impact on our understanding of the interplay between network dynamics and social evolution.

Jennifer Fewell (Arizona State University; School of Life Sciences)

2003-09-26

280

Applications to aging networks.  

PubMed

This chapter will introduce a few additional network concepts, and then it will focus on the application of the material in the previous chapter to the study of systems biology of aging. In particular, we will examine how the material can be used to study aging networks in two sample species: Caenorhabditis elegans and Saccharomyces cerevisiae. PMID:25341510

Wimble, Christopher; Witten, Tarynn M

2015-01-01

281

CAISSON: Interconnect Network Simulator  

NASA Technical Reports Server (NTRS)

Cray response to HPCS initiative. Model future petaflop computer interconnect. Parallel discrete event simulation techniques for large scale network simulation. Built on WarpIV engine. Run on laptop and Altix 3000. Can be sized up to 1000 simulated nodes per host node. Good parallel scaling characteristics. Flexible: multiple injectors, arbitration strategies, queue iterators, network topologies.

Springer, Paul L.

2006-01-01

282

Academe's New Girl Network  

ERIC Educational Resources Information Center

A "networking" processing pioneered by the Committee for the Concerns of Women in New England Colleges and Universities, which is establishing a New Girl network to compete with and eventually mesh with the Old Boy system, is described. Lobbying and conference efforts of HERS (Higher Education Resource Services) are reported. (LBH)

Stent, Angela

1978-01-01

283

The Deep Space Network  

NASA Technical Reports Server (NTRS)

Deep Space Network progress in flight project support, tracking and data acquisition, research and technology, network engineering, hardware and software implementation, and operations is cited. Topics covered include: tracking and ground based navigation; spacecraft/ground communication; station control and operations technology; ground communications; and deep space stations.

1979-01-01

284

Multicommodity Capacitated Network Design  

Microsoft Academic Search

This paper presents a comprehensive survey of models and algorithms for multicommoditycapacitated network design problems, which are mostly encountered in telecommunicationsand transportation network planning. These problems are important not onlydue to the major relevance of their applications, but also because they pose considerablemodeling and algorithmic challenges. We present a general arc-based model, describeuseful alternative formulations and survey the literature on

Bernard Gendron; Teodor Gabriel Crainic; Antonio Frangioni

1997-01-01

285

Mobile Computing/ Mobile Networks  

E-print Network

Multicast Interoperability Network reliability (TCP) Quality of service (QoS) #12;2 3 The Internet 1969) in 1969 They documented the Internet protocols Email was developed Networked 4 computers together Government also funded universities for research 4 1989-1990 Transfer of Internet from Government

Yu, Chansu

286

PESTICIDE INFORMATION NETWORK  

EPA Science Inventory

The Pesticide Information Network (PIN) is an interactive database containing information about pesticides. PIN is a free service offered by the USEPAs Office of Pesticide Programs which provides contacts on pesticide issues, has a bulletin board network for public and private us...

287

Hubless satellite communications networks  

NASA Technical Reports Server (NTRS)

Frequency Comb Multiple Access (FCMA) is a new combined modulation and multiple access method which will allow cheap hubless Very Small Aperture Terminal (VSAT) networks to be constructed. Theoretical results show bandwidth efficiency and power efficiency improvements over other modulation and multiple access methods. Costs of the VSAT network are reduced dramatically since a hub station is not required.

Robinson, Peter Alan

1994-01-01

288

A Distributed Magnetometer Network  

E-print Network

Various possiblities for a distributed magnetometer network are considered. We discuss strategies such as croudsourcing smartphone magnetometer data, the use of trees as magnetometers, and performing interferometry using magnetometer arrays to synthesize the magnetometers into the world's largest telescope. Geophysical and other applications of such a network are discussed.

Scoville, John; Freund, Friedemann

2014-01-01

289

Network Collaboration with UNIX.  

ERIC Educational Resources Information Center

Discusses networking as a collaboration tool in the teaching of technical writing. Argues that some degree of collaboration is innate to all writing, that word processing already facilitates that collaboration, and that networking is the next enhancement to the collaborative process. (RS)

Horn, Wm. Dennis

1993-01-01

290

TOXNET (TOXICOLOGY DATA NETWORK)  

EPA Science Inventory

TOXNET (Toxicology Data Network) is a computerized system of files oriented to toxicology and related areas. It is managed by the National Library of Medicines Toxicology and Environmental Health Information Program (TEHIP) and runs on a series of microcomputers in a networked cl...

291

Modeling semiflexible polymer networks  

E-print Network

Here, we provide an overview of theoretical approaches to semiflexible polymers and their networks. Such semiflexible polymers have large bending rigidities that can compete with the entropic tendency of a chain to crumple up into a random coil. Many studies on semiflexible polymers and their assemblies have been motivated by their importance in biology. Indeed, crosslinked networks of semiflexible polymers form a major structural component of tissue and living cells. Reconstituted networks of such biopolymers have emerged as a new class of biological soft matter systems with remarkable material properties, which have spurred many of the theoretical developments discussed here. Starting from the mechanics and dynamics of individual semiflexible polymers, we review the physics of semiflexible bundles, entangled solutions and disordered cross-linked networks. Finally, we discuss recent developments on marginally stable fibrous networks, which exhibit critical behavior similar to other marginal systems such as jammed soft matter.

Chase P. Broedersz; Fred. C. MacKintosh

2014-04-16

292

Dynamic Network Delay Cartography  

E-print Network

Path delays in IP networks are important metrics, required by network operators for assessment, planning, and fault diagnosis. Monitoring delays of all source-destination pairs in a large network is however challenging and wasteful of resources. The present paper advocates a spatio-temporal Kalman filtering approach to construct network-wide delay maps using measurements on only a few paths. The proposed network cartography framework allows efficient tracking and prediction of delays by relying on both topological as well as historical data. Optimal paths for delay measurement are selected in an online fashion by leveraging the notion of submodularity. The resulting predictor is optimal in the class of linear predictors, and outperforms competing alternatives on real-world datasets.

Rajawat, Ketan; Giannakis, Georgios B

2012-01-01

293

Collective network routing  

DOEpatents

Disclosed are a unified method and apparatus to classify, route, and process injected data packets into a network so as to belong to a plurality of logical networks, each implementing a specific flow of data on top of a common physical network. The method allows to locally identify collectives of packets for local processing, such as the computation of the sum, difference, maximum, minimum, or other logical operations among the identified packet collective. Packets are injected together with a class-attribute and an opcode attribute. Network routers, employing the described method, use the packet attributes to look-up the class-specific route information from a local route table, which contains the local incoming and outgoing directions as part of the specifically implemented global data flow of the particular virtual network.

Hoenicke, Dirk

2014-12-02

294

Self Evolving Modular Network  

NASA Astrophysics Data System (ADS)

We propose a novel modular network called the Self-Evolving Modular Network (SEEM). The SEEM has a modular network architecture with a graph structure and these following advantages: (1) new modules are added incrementally to allow the network to adapt in a self-organizing manner, and (2) graph's paths are formed based on the relationships between the models represented by modules. The SEEM is expected to be applicable to evolving functions of an autonomous robot in a self-organizing manner through interaction with the robot's environment and categorizing large-scale information. This paper presents the architecture and an algorithm for the SEEM. Moreover, performance characteristic and effectiveness of the network are shown by simulations using cubic functions and a set of 3D-objects.

Tokunaga, Kazuhiro; Kawabata, Nobuyuki; Furukawa, Tetsuo

295

Introduction to Network Analysis 1 Epidemics on Networks  

E-print Network

for Large Networks connections between open sites, i.e., the utility of network infection at node i is lessIntroduction to Network Analysis 1 Epidemics on Networks Analysis of infection spread: · In theory could catch one if comes into contact with infected individual Susceptible Someone who has the disease

Safro, Ilya

296

Maximum Network Lifetime in Fault Tolerant Sensor Networks  

E-print Network

Maximum Network Lifetime in Fault Tolerant Sensor Networks Petar Djukic and Shahrokh Valaee introduces a novel technique to maxi- mize the lifetime of fault tolerant sensor networks. The proposed-- Sensor networks, system design, fault tolerance, mathematical programming/optimization I. INTRODUCTION

Valaee, Shahrokh

297

Prolonging Network Lifetime for Target Coverage in Sensor Networks  

E-print Network

Prolonging Network Lifetime for Target Coverage in Sensor Networks Yuzhen Liu and Weifa Liang. Target coverage is a fundamental problem in sensor networks for environment monitoring and surveillance purposes. To prolong the network lifetime, a typical approach is to partition the sensors in a net- work

Liang, Weifa

298

Introduction to Network Analysis 1 Introduction to Network Analysis  

E-print Network

Introduction to Network Analysis 1 Introduction to Network Analysis Instructor: Ilya Safro, 228 McAdams Hall Course: Introduction to Network Analysis, CP SC 881 Time: 2:30-3:45 MW Place: 114 McAdams Hall). Points Grade 92 A 80 B 60 C 0 F #12;Introduction to Network Analysis 2 Recommended Books (optional

Safro, Ilya

299

Network Resilience:Network Resilience: JANET and the LHCOPN  

E-print Network

Network Resilience:Network Resilience: JANET and the LHCOPN Robin Tasker STFC, Daresbury Laboratory ­ Overview, Status and Resilienceand Resilience Your university or experiment logo here27/03/2009 Network Resilience: JANET and the LHCOPN #12;JANET Network Update Upgrading to STM-256 (aka 40Gbits/s) Configuration

University College London

300

Enhancing business networks using social network based virtual communities  

Microsoft Academic Search

Purpose – To enhance an entrepreneur's business network through the integration of the social network concepts and design principles of virtual communities. Design\\/methodology\\/approach – This study documents the design and initial deployment of a virtual community case, Innovation Information Infrastructure, based on social network concepts. Findings – Basic design principles, deployment strategy, and future directions for social network-based virtual communities

Bih-ru Lea; Wen-bin Yu; Nisha Maguluru; Michael Nichols

2006-01-01

301

NETWORKS OF PRACTICE AS HETEROGENEOUS ACTOR-NETWORKS  

Microsoft Academic Search

This paper discusses some of the difficulties involved in using the concepts of ‘communities of practice’ and ‘networks of practice’ when understanding the exchange of knowledge among globally dispersed communities of professionals. It proposes rethinking ‘networks of practice’ as heterogeneous networks in the sense used by the actor-network theory. The revised concept is illustrated with examples from the author's study

Yuri Takhteyev

2009-01-01

302

Cisco Network Admission Control and Microsoft Network Access Protection  

E-print Network

Cisco Network Admission Control and Microsoft Network Access Protection Interoperability Architecture Cisco Systems and Microsoft Corporation Published:September 2006 #12; Abstract Cisco Systems®, Inc the NetworkAdmission Control (NAC) platform available from Cisco® and the NetworkAccess Protection (NAP

Hunt, Galen

303

Chapter 5. Communications and Networking Communication and Network  

E-print Network

and Networking 5-2 RLE Progress Report 152 1. Future Optical Network Architecture Sponsors DARPA ­ FONA: HR0011 to the realization of Network-Centric Warfare in the defense world. Sustained exponential growth in communications cost-effective communications in the future. Cost optimized optical network architecture

304

Improved Autoassociative Neural Networks  

NASA Technical Reports Server (NTRS)

Improved autoassociative neural networks, denoted nexi, have been proposed for use in controlling autonomous robots, including mobile exploratory robots of the biomorphic type. In comparison with conventional autoassociative neural networks, nexi would be more complex but more capable in that they could be trained to do more complex tasks. A nexus would use bit weights and simple arithmetic in a manner that would enable training and operation without a central processing unit, programs, weight registers, or large amounts of memory. Only a relatively small amount of memory (to hold the bit weights) and a simple logic application- specific integrated circuit would be needed. A description of autoassociative neural networks is prerequisite to a meaningful description of a nexus. An autoassociative network is a set of neurons that are completely connected in the sense that each neuron receives input from, and sends output to, all the other neurons. (In some instantiations, a neuron could also send output back to its own input terminal.) The state of a neuron is completely determined by the inner product of its inputs with weights associated with its input channel. Setting the weights sets the behavior of the network. The neurons of an autoassociative network are usually regarded as comprising a row or vector. Time is a quantized phenomenon for most autoassociative networks in the sense that time proceeds in discrete steps. At each time step, the row of neurons forms a pattern: some neurons are firing, some are not. Hence, the current state of an autoassociative network can be described with a single binary vector. As time goes by, the network changes the vector. Autoassociative networks move vectors over hyperspace landscapes of possibilities.

Hand, Charles

2003-01-01

305

Scatterable Sensor Networks for Network Centric Warfare Applications  

Microsoft Academic Search

This paper investigates the utility of realistic, time and scale-constrained sensor networks in cooperation with semi-autonomous robots as envisioned in future Network-Centric Warfare. The particular application chosen is a networked minefield based roughly on the United States Military Family of Scatterable Mines (FASCAM) with similar emplacement and planning techniques. Algorithms for sensor network operation and sensor network control are provided.

Kenneth E. Viall

2007-01-01

306

Application of network theory to potential mycorrhizal networks  

Microsoft Academic Search

The concept of a common mycorrhizal network implies that the arrangement of plants and mycorrhizal fungi in a community shares\\u000a properties with other networks. A network is a system of nodes connected by links. Here we apply network theory to mycorrhizas\\u000a to determine whether the architecture of a potential common mycorrhizal network is random or scale-free. We analyzed mycorrhizal\\u000a data

D. Southworth; X.-H. He; W. Swenson; C. S. Bledsoe; W. R. Horwath

2005-01-01

307

Seawind: a Wireless Network Emulator  

Microsoft Academic Search

Behavior of current communication protocols as well as current and future networked ap- plications is of fundamental importance for technical and commercial success of Mobile Internet. The forthcoming wireless Wide-Area Networks, such as GPRS and UMTS, are quite complex and network operators have a large set of parameters to tune the transfer performance of these networks. In this situation it

Markku Kojo; Andrei Gurtov; Jukka Manner; Pasi Sarolahti; Timo O. Alanko; Kimmo E. E. Raatikainen

2001-01-01

308

Network Leadership: An Emerging Practice  

ERIC Educational Resources Information Center

Network leadership is an emerging approach that can have an impact on change in education and in society. According to Merriam-Webster (2011), a network is "an interconnected or interrelated chain, group, or system." Intentional interconnectedness is what separates network leadership from other leadership theories. Network leadership has the…

Tremblay, Christopher W.

2012-01-01

309

Wireless sensor networks: a survey  

Microsoft Academic Search

This paper describes the concept of sensor networks which has been made viable by the convergence of micro- electro-mechanical systems technology, wireless communications and digital electronics. First, the sensing tasks and the potential sensor networks applications are explored, and a review of factors influencing the design of sensor networks is provided. Then, the communication architecture for sensor networks is outlined,

Ian F. Akyildiz; Weilian Su; Yogesh Sankarasubramaniam; Erdal Cayirci

2002-01-01

310

Hybrid learning in expert networks  

Microsoft Academic Search

Expert networks are defined as the embodiment of an expert's rule-based knowledge in an acyclic feedforward network. A transformation process is used to create an expert network from an expert system to enable training of the certainty factors of the expert system's rules from data. Certainty factors in the expert system correspond to connection weights in the network. The training

S. I. Hruska; D. C. Kuncicky; R. C. Lacher

1991-01-01

311

The Georgia Tech Network Simulator  

Microsoft Academic Search

We introduce a new network simulation environment, developed by our research group, called the Georgia Tech Network Simulator (GTNetS). Our simulator is designed specifically to allow much larger-scale simulations than can easily be created by existing network simulation tools. The design of the simulator very closely matches the design of real network protocol stacks and hardware. Thus, anyone with a

George F. Riley

2003-01-01

312

Managing Network Resources in Condor  

Microsoft Academic Search

Data-intensive applications in the Condor High Throughput Computing environment can place heavy demands on network resources for checkpointing and remote data access. We have developed mechanisms to monitor, control, and schedule network usage in Condor. By managing network resources, these mechanisms provide administrative control over Condor's network usage and improve the execution efficiency of Condor applications.

Jim Basney; Miron Livny

2000-01-01

313

Micromagnetic study of network media  

Microsoft Academic Search

Magnetic hysteresis and recording properties of network film media were studied via micromagnetic modeling. It was found that the chain-like arrangement of magnetic grains in the network media suppresses clustering magnetization reversal. In comparison with conventional thin film medium, the network medium exhibits lower transition noise at high recording densities. The network medium is also more thermally stable than the

Jian-Gang Zhu; Hao Fang

1998-01-01

314

Optical Network Testbeds Workshop  

SciTech Connect

This is the summary report of the third annual Optical Networking Testbed Workshop (ONT3), which brought together leading members of the international advanced research community to address major challenges in creating next generation communication services and technologies. Networking research and development (R&D) communities throughout the world continue to discover new methods and technologies that are enabling breakthroughs in advanced communications. These discoveries are keystones for building the foundation of the future economy, which requires the sophisticated management of extremely large qualities of digital information through high performance communications. This innovation is made possible by basic research and experiments within laboratories and on specialized testbeds. Initial network research and development initiatives are driven by diverse motives, including attempts to solve existing complex problems, the desire to create powerful new technologies that do not exist using traditional methods, and the need to create tools to address specific challenges, including those mandated by large scale science or government agency mission agendas. Many new discoveries related to communications technologies transition to wide-spread deployment through standards organizations and commercialization. These transition paths allow for new communications capabilities that drive many sectors of the digital economy. In the last few years, networking R&D has increasingly focused on advancing multiple new capabilities enabled by next generation optical networking. Both US Federal networking R&D and other national R&D initiatives, such as those organized by the National Institute of Information and Communications Technology (NICT) of Japan are creating optical networking technologies that allow for new, powerful communication services. Among the most promising services are those based on new types of multi-service or hybrid networks, which use new optical networking technologies. Several years ago, when many of these optical networking research topics were first being investigated, they were the subject of controversial debate. The new techniques challenged many long-held concepts related to architecture and technology. However, today all major networking organizations are transitioning toward infrastructure that incorporates these new concepts. This progress has been assisted through the series of Optical Networking Testbed Workshops (ONT). The first (ONT1) outlined a general framework of key issues and topics and developed a series of recommendations (www.nren.nasa.gov/workshop7). The second (ONT2) developed a common vision of optical network technologies, services, infrastructure, and organizations (www.nren.nasa.gov/workshop8). Processes that allow for a common vision encourage widespread deployment of these types of resources among advanced networking communities. Also, such a shared vision enables key concepts and technologies to migrate from basic research testbeds to wider networking communities. The ONT-3 workshop built on these earlier activities by expanding discussion to include additional considerations of the international interoperability and of greater impact of optical networking technology on networking in general. In accordance with this recognition, the workshop confirmed that future-oriented research and development is indispensable to fundamentally change the current Internet architecture to create a global network incorporating completely new concepts. The workshop also recognized that the first priority to allow for this progress is basic research and development, including international collaborative activities, which are important for the global realization of interoperability of a new generation architecture.

Joe Mambretti

2007-06-01

315

Toward Optimal Transport Networks  

NASA Technical Reports Server (NTRS)

Strictly evolutionary approaches to improving the air transport system a highly complex network of interacting systems no longer suffice in the face of demand that is projected to double or triple in the near future. Thus evolutionary approaches should be augmented with active design methods. The ability to actively design, optimize and control a system presupposes the existence of predictive modeling and reasonably well-defined functional dependences between the controllable variables of the system and objective and constraint functions for optimization. Following recent advances in the studies of the effects of network topology structure on dynamics, we investigate the performance of dynamic processes on transport networks as a function of the first nontrivial eigenvalue of the network's Laplacian, which, in turn, is a function of the network s connectivity and modularity. The last two characteristics can be controlled and tuned via optimization. We consider design optimization problem formulations. We have developed a flexible simulation of network topology coupled with flows on the network for use as a platform for computational experiments.

Alexandrov, Natalia; Kincaid, Rex K.; Vargo, Erik P.

2008-01-01

316

Complex Semantic Networks  

NASA Astrophysics Data System (ADS)

Verbal language is a dynamic mental process. Ideas emerge by means of the selection of words from subjective and individual characteristics throughout the oral discourse. The goal of this work is to characterize the complex network of word associations that emerge from an oral discourse from a discourse topic. Because of that, concepts of associative incidence and fidelity have been elaborated and represented the probability of occurrence of pairs of words in the same sentence in the whole oral discourse. Semantic network of words associations were constructed, where the words are represented as nodes and the edges are created when the incidence-fidelity index between pairs of words exceeds a numerical limit (0.001). Twelve oral discourses were studied. The networks generated from these oral discourses present a typical behavior of complex networks and their indices were calculated and their topologies characterized. The indices of these networks obtained from each incidence-fidelity limit exhibit a critical value in which the semantic network has maximum conceptual information and minimum residual associations. Semantic networks generated by this incidence-fidelity limit depict a pattern of hierarchical classes that represent the different contexts used in the oral discourse.

Teixeira, G. M.; Aguiar, M. S. F.; Carvalho, C. F.; Dantas, D. R.; Cunha, M. V.; Morais, J. H. M.; Pereira, H. B. B.; Miranda, J. G. V.

317

Simulated Associating Polymer Networks  

NASA Astrophysics Data System (ADS)

Telechelic associating polymer networks consist of polymer chains terminated by endgroups that have a different chemical composition than the polymer backbone. When dissolved in a solution, the endgroups cluster together to form aggregates. At low temperature, a strongly connected reversible network is formed and the system behaves like a gel. Telechelic networks are of interest since they are representative for biopolymer networks (e.g. F-actin) and are widely used in medical applications (e.g. hydrogels for tissue engineering, wound dressings) and consumer products (e.g. contact lenses, paint thickeners). In this thesis such systems are studied by means of a molecular dynamics/Monte Carlo simulation. At first, the system in rest is studied by means of graph theory. The changes in network topology upon cooling to the gel state, are characterized. Hereto an extensive study of the eigenvalue spectrum of the gel network is performed. As a result, an in-depth investigation of the eigenvalue spectra for spatial ER, scale-free, and small-world networks is carried out. Next, the gel under the application of a constant shear is studied, with a focus on shear banding and the changes in topology under shear. Finally, the relation between the gel transition and percolation is discussed.

Billen, Joris

318

Stochastically evolving networks  

NASA Astrophysics Data System (ADS)

We discuss a class of models for the evolution of networks in which new nodes are recruited into the network at random times, and links between existing nodes that are not yet directly connected may also form at random times. The class contains both models that produce “small-world” networks and less tightly linked models. We produce both trees, appropriate in certain biological applications, and networks in which closed loops can appear, which model communication networks and networks of human sexual interactions. One of our models is closely related to random recursive trees, and some exact results known in that context can be exploited. The other models are more subtle and difficult to analyze. Our analysis includes a number of exact results for moments, correlations, and distributions of coordination number and network size. We report simulations and also discuss some mean-field approximations. If the system has evolved for a long time and the state of a random node (which thus has a random age) is observed, power-law distributions for properties of the system arise in some of these models.

Chan, Derek Y.; Hughes, Barry D.; Leong, Alex S.; Reed, William J.

2003-12-01

319

Parallel consensual neural networks.  

PubMed

A new type of a neural-network architecture, the parallel consensual neural network (PCNN), is introduced and applied in classification/data fusion of multisource remote sensing and geographic data. The PCNN architecture is based on statistical consensus theory and involves using stage neural networks with transformed input data. The input data are transformed several times and the different transformed data are used as if they were independent inputs. The independent inputs are first classified using the stage neural networks. The output responses from the stage networks are then weighted and combined to make a consensual decision. In this paper, optimization methods are used in order to weight the outputs from the stage networks. Two approaches are proposed to compute the data transforms for the PCNN, one for binary data and another for analog data. The analog approach uses wavelet packets. The experimental results obtained with the proposed approach show that the PCNN outperforms both a conjugate-gradient backpropagation neural network and conventional statistical methods in terms of overall classification accuracy of test data. PMID:18255610

Benediktsson, J A; Sveinsson, J R; Ersoy, O K; Swain, P H

1997-01-01

320

Markets on Networks  

NASA Astrophysics Data System (ADS)

The dynamics of human, and most biological populations is characterized by competition for resources. By its own nature, this dynamics creates the group of "elites", formed by those agents who have strategies that are the most successful in the given situation, and therefore the rest of the agents will tend to follow, imitate, or interact with them, creating a social structure of leadership in the agent society. These inter-agent communications generate a complex social network with small-world character which itself forms the substrate for a second network, the action network. The latter is a highly dynamic, adaptive, directed network, defined by those inter-agent communication links on the substrate along which the passed information /prediction is acted upon by the other agents. By using the minority game for competition dynamics, here we show that when the substrate network is highly connected, the action network spontaneously develops hubs with a broad distribution of out-degrees, defining a robust leadership structure that is scale-free. Furthermore, in certain, realistic parameter ranges, facilitated by information passing on the action network, agents can spontaneously generate a high degree of cooperation making the collective almost maximally efficient.

Toroczkai, Zoltan; Anghel, Marian; Bassler, Kevin; Korniss, Gyorgy

2003-03-01

321

Network aware distributed applications  

SciTech Connect

Most distributed applications today manage to utilize only a small percentage of the needed and available network bandwidth. Often application developers are not aware of the potential bandwidth of the network, and therefore do not know what to expect. Even when application developers are aware of the specifications of the machines and network links, they have few resources that can help determine why the expected performance was not achieved. What is needed is a ubiquitous and easy-to-use service that provides reliable, accurate, secure, and timely estimates of dynamic network properties. This service will help advise applications on how to make use of the network's increasing bandwidth and capabilities for traffic shaping and engineering. When fully implemented, this service will make building currently unrealizable levels of network awareness into distributed applications a relatively mundane task. For example, a remote data visualization application could choose between sending a wireframe, a pre-rendered image, or a 3-D representation, based on forecasts of CPU availability and power, compression options, and available bandwidth. The same service will provide on-demand performance information so that applications can compare predicted with actual results, and allow detailed queries about the end-to-end path for application and network tuning and debugging.

Agarwal, Deborah; Tierney, Brian L.; Gunter, Dan; Lee, Jason; Johnston, William

2001-02-04

322

Network connectivity entropy and its application on network connectivity reliability  

NASA Astrophysics Data System (ADS)

The network structure entropy has served as one of the index measuring network heterogeneity, but it gives no considerations to the impact of isolated nodes on the network structure. In addition, the all-terminal reliability is zero and is unable to compare it between disconnected networks. Therefore, the concept of network connectivity entropy is suggested to remove the current bottleneck and helps facilitate new index in terms of network connectivity reliability. This study fully proves the rules as follows: when the edges of network are diminishing, the newly-established network connectivity reliability will remain unchanged or become weaker; conversely, when the edges of network are increasing, the network connectivity reliability will remain unchanged or become stronger. Thus, the proposed index of network connectivity reliability is proved reasonable. Furthermore, the impaired metro network of Nanjing city is exemplified to demonstrate the validity and practicability of network connectivity reliability. The result shows that this new approach is in good position to compute network connectivity reliability quickly and effectively, and also to compare it between different networks.

Wu, Liusan; Tan, Qingmei; Zhang, Yuehui

2013-11-01

323

The Orphan Disease Networks  

PubMed Central

The low prevalence rate of orphan diseases (OD) requires special combined efforts to improve diagnosis, prevention, and discovery of novel therapeutic strategies. To identify and investigate relationships based on shared genes or shared functional features, we have conducted a bioinformatic-based global analysis of all orphan diseases with known disease-causing mutant genes. Starting with a bipartite network of known OD and OD-causing mutant genes and using the human protein interactome, we first construct and topologically analyze three networks: the orphan disease network, the orphan disease-causing mutant gene network, and the orphan disease-causing mutant gene interactome. Our results demonstrate that in contrast to the common disease-causing mutant genes that are predominantly nonessential, a majority of orphan disease-causing mutant genes are essential. In confirmation of this finding, we found that OD-causing mutant genes are topologically important in the protein interactome and are ubiquitously expressed. Additionally, functional enrichment analysis of those genes in which mutations cause ODs shows that a majority result in premature death or are lethal in the orthologous mouse gene knockout models. To address the limitations of traditional gene-based disease networks, we also construct and analyze OD networks on the basis of shared enriched features (biological processes, cellular components, pathways, phenotypes, and literature citations). Analyzing these functionally-linked OD networks, we identified several additional OD-OD relations that are both phenotypically similar and phenotypically diverse. Surprisingly, we observed that the wiring of the gene-based and other feature-based OD networks are largely different; this suggests that the relationship between ODs cannot be fully captured by the gene-based network alone. PMID:21664998

Zhang, Minlu; Zhu, Cheng; Jacomy, Alexis; Lu, Long J.; Jegga, Anil G.

2011-01-01

324

Attractor Metabolic Networks  

PubMed Central

Background The experimental observations and numerical studies with dissipative metabolic networks have shown that cellular enzymatic activity self-organizes spontaneously leading to the emergence of a Systemic Metabolic Structure in the cell, characterized by a set of different enzymatic reactions always locked into active states (metabolic core) while the rest of the catalytic processes are only intermittently active. This global metabolic structure was verified for Escherichia coli, Helicobacter pylori and Saccharomyces cerevisiae, and it seems to be a common key feature to all cellular organisms. In concordance with these observations, the cell can be considered a complex metabolic network which mainly integrates a large ensemble of self-organized multienzymatic complexes interconnected by substrate fluxes and regulatory signals, where multiple autonomous oscillatory and quasi-stationary catalytic patterns simultaneously emerge. The network adjusts the internal metabolic activities to the external change by means of flux plasticity and structural plasticity. Methodology/Principal Findings In order to research the systemic mechanisms involved in the regulation of the cellular enzymatic activity we have studied different catalytic activities of a dissipative metabolic network under different external stimuli. The emergent biochemical data have been analysed using statistical mechanic tools, studying some macroscopic properties such as the global information and the energy of the system. We have also obtained an equivalent Hopfield network using a Boltzmann machine. Our main result shows that the dissipative metabolic network can behave as an attractor metabolic network. Conclusions/Significance We have found that the systemic enzymatic activities are governed by attractors with capacity to store functional metabolic patterns which can be correctly recovered from specific input stimuli. The network attractors regulate the catalytic patterns, modify the efficiency in the connection between the multienzymatic complexes, and stably retain these modifications. Here for the first time, we have introduced the general concept of attractor metabolic network, in which this dynamic behavior is observed. PMID:23554883

De la Fuente, Ildefonso M.; Cortes, Jesus M.; Pelta, David A.; Veguillas, Juan

2013-01-01

325

Functional Molecular Ecological Networks  

PubMed Central

Biodiversity and its responses to environmental changes are central issues in ecology and for society. Almost all microbial biodiversity research focuses on “species” richness and abundance but not on their interactions. Although a network approach is powerful in describing ecological interactions among species, defining the network structure in a microbial community is a great challenge. Also, although the stimulating effects of elevated CO2 (eCO2) on plant growth and primary productivity are well established, its influences on belowground microbial communities, especially microbial interactions, are poorly understood. Here, a random matrix theory (RMT)-based conceptual framework for identifying functional molecular ecological networks was developed with the high-throughput functional gene array hybridization data of soil microbial communities in a long-term grassland FACE (free air, CO2 enrichment) experiment. Our results indicate that RMT is powerful in identifying functional molecular ecological networks in microbial communities. Both functional molecular ecological networks under eCO2 and ambient CO2 (aCO2) possessed the general characteristics of complex systems such as scale free, small world, modular, and hierarchical. However, the topological structures of the functional molecular ecological networks are distinctly different between eCO2 and aCO2, at the levels of the entire communities, individual functional gene categories/groups, and functional genes/sequences, suggesting that eCO2 dramatically altered the network interactions among different microbial functional genes/populations. Such a shift in network structure is also significantly correlated with soil geochemical variables. In short, elucidating network interactions in microbial communities and their responses to environmental changes is fundamentally important for research in microbial ecology, systems microbiology, and global change. PMID:20941329

Zhou, Jizhong; Deng, Ye; Luo, Feng; He, Zhili; Tu, Qichao; Zhi, Xiaoyang

2010-01-01

326

The Gay Financial Network  

NSDL National Science Digital Library

In his mission statement, Walter B. Schubert, CEO and president of the Gay Financial Network (GFN), explains the driving force behind GFN's creation: "To build the first all encompassing financial services Web site to empower the American gay and lesbian community..." The Gay Financial Network is a financial news portal that targets the gay community. The articles are divided into several "channels" including Gay Financial News, Financial Planning, Home and Office, and Women's Channel. Financial services include information on online trading, banking, mortgages, and annuities. GFN also provides professional tools such as a gay and gay-friendly professionals directory and articles and information for career networking.

327

Network Security: Concepts  

NSDL National Science Digital Library

Prepared and presented by Professor Raj Jain at Washington University in St. Louis, this series of presentations is designed to introduce computer science students to the fundamentals of network security. Visitors have the option of choosing to download or view the presentations with audio, as individual slides only, or as a single PDF document. Topics here include: security requirements, public key encryption, digital signatures, and confidentiality. This is an excellent site for educators to use in the classroom or as a supplementary resource to introduce students to computer network security. Students may also wish to view or download the presentations to learn the basic concepts of network security.

Jain, Raj

328

Learning In networks  

NASA Technical Reports Server (NTRS)

Intelligent systems require software incorporating probabilistic reasoning, and often times learning. Networks provide a framework and methodology for creating this kind of software. This paper introduces network models based on chain graphs with deterministic nodes. Chain graphs are defined as a hierarchical combination of Bayesian and Markov networks. To model learning, plates on chain graphs are introduced to model independent samples. The paper concludes by discussing various operations that can be performed on chain graphs with plates as a simplification process or to generate learning algorithms.

Buntine, Wray L.

1995-01-01

329

NIRVANA network requirements  

SciTech Connect

NIRVANA is an effort to standardize electrical computer-aided design workstations at Sandia National Laboratories in Albuquerque, New Mexico. The early effect of this project will be the introduction of at least 60 new engineering workstations at Sandia National Laboratories. Albuquerque, and at Allied Signal, Kansas City Division. These workstations are expected to begin arriving in September 1990. This paper proposes a design and outlines the requirements for a network to support the NIRVANA project. The author proposes a near-term network design, describes the security profile and caveats of this design, and proposes a long-term networking strategy for NIRVANA. 6 refs., 7 figs.

Wood, B.J.

1990-08-01

330

ONE: The Ohio Network Emulator  

Microsoft Academic Search

Studying network protocols and distributed applications in real networks can bedifficult due to the need for complex topologies, hard to find physical channels (e.g.,satellite channels), and conditions beyond the control of a researcher (e.g., queue sizes).Network emulators can provide a controlled and reproducible environment for networktesting. This paper discusses ONE, a network emulator we have written and tested.1 IntroductionNetwork emulators,

Adam Caldwell; Mark Allman; Shawn Ostermann

1996-01-01

331

Trust Maximization in Social Networks  

NASA Astrophysics Data System (ADS)

Trust is a human-related phenomenon in social networks. Trust research on social networks has gained much attention on its usefulness, and on modeling propagations. There is little focus on finding maximum trust in social networks which is particularly important when a social network is oriented by certain tasks. In this paper, we propose a trust maximization algorithm based on the task-oriented social networks.

Zhan, Justin; Fang, Xing

332

Relating Network Synaptic Connectivity and Network Activity in the Lobster (Panulirus interruptus) Pyloric Network  

E-print Network

Relating Network Synaptic Connectivity and Network Activity in the Lobster (Panulirus interruptus in the lobster (Panulirus interrup- tus) pyloric network. J Neurophysiol 90: 2378­2386, 2003. First published June 11, 2003; 10.1152/jn.00705.2002. The lobster pyloric network has a densely interconnected synaptic

Hooper, Scott

333

Fluvial network organization imprints on microbial co-occurrence networks.  

PubMed

Recent studies highlight linkages among the architecture of ecological networks, their persistence facing environmental disturbance, and the related patterns of biodiversity. A hitherto unresolved question is whether the structure of the landscape inhabited by organisms leaves an imprint on their ecological networks. We analyzed, based on pyrosequencing profiling of the biofilm communities in 114 streams, how features inherent to fluvial networks affect the co-occurrence networks that the microorganisms form in these biofilms. Our findings suggest that hydrology and metacommunity dynamics, both changing predictably across fluvial networks, affect the fragmentation of the microbial co-occurrence networks throughout the fluvial network. The loss of taxa from co-occurrence networks demonstrates that the removal of gatekeepers disproportionately contributed to network fragmentation, which has potential implications for the functions biofilms fulfill in stream ecosystems. Our findings are critical because of increased anthropogenic pressures deteriorating stream ecosystem integrity and biodiversity. PMID:25136087

Widder, Stefanie; Besemer, Katharina; Singer, Gabriel A; Ceola, Serena; Bertuzzo, Enrico; Quince, Christopher; Sloan, William T; Rinaldo, Andrea; Battin, Tom J

2014-09-01

334

Identification of influential nodes in network of networks  

E-print Network

The network of networks(NON) research is focused on studying the properties of n interdependent networks which is ubiquitous in the real world. Identifying the influential nodes in the network of networks is theoretical and practical significance. However, it is hard to describe the structure property of the NON based on traditional methods. In this paper, a new method is proposed to identify the influential nodes in the network of networks base on the evidence theory. The proposed method can fuse different kinds of relationship between the network components to constructed a comprehensive similarity network. The nodes which have a big value of similarity are the influential nodes in the NON. The experiment results illustrate that the proposed method is reasonable and significant

Li, Meizhu; Liu, Qi; Deng, Yong

2015-01-01

335

NSIUWG: Science networking retreat  

NASA Technical Reports Server (NTRS)

The purpose of this session was to study and identify alternatives to be recommended for the science networking areas of vision; roles and responsibilities; and technical approach and transition. This presentation is represented by charts and viewgraphs only.

Hart, Jim

1991-01-01

336

RESEARCH HIGHLIGHTS QUANTUM NETWORKS  

E-print Network

of the process. The success of this procedure marks a significant advance on the road towards the realization of a quantum network protocol. NONLINEAR OPTICS At a stretch Opt.Lett.Doc.ID:81112 (2007) A long interaction

Fan, Xudong "Sherman"

337

Configuring the Networked Citizen  

Microsoft Academic Search

Among legal scholars of technology, it has become commonplace to acknowledge that the design of networked information technologies has regulatory effects. For the most part, that discussion has been structured by the taxonomy developed by Lawrence Lessig, which classifies \\

Julie E. Cohen

2012-01-01

338

The Deep Space Network  

NASA Technical Reports Server (NTRS)

Progress on the Deep Space Network (DSN) supporting research and technology, advanced development, engineering and implementation, and DSN operations is presented. The functions and facilities of the DSN are described.

1979-01-01

339

Architecting space communication networks  

E-print Network

Reliable communication and navigation services are critical to robotic and human space missions. NASA currently provides them through three independent and uncoordinated network that consist of both Earth-based and space-based ...

Sanchez Net, Marc

2014-01-01

340

Essays on Network Formation  

E-print Network

This dissertation contains two essays which examine the roles that individual incentives, competition, and information play in network formation. In the first essay, I examine a model in which two competing groups offer different allocation rules...

Mueller, William Graham

2012-10-19

341

Growing networks with superjoiners.  

PubMed

We study the Krapivsky-Redner (KR) network growth model, but where new nodes can connect to any number of existing nodes, m, picked from a power-law distribution p(m)?m^{-?}. Each of the m new connections is still carried out as in the KR model with probability redirection r (corresponding to degree exponent ?_{KR}=1+1/r in the original KR model). The possibility to connect to any number of nodes resembles a more realistic type of growth in several settings, such as social networks, routers networks, and networks of citations. Here we focus on the in-, out-, and total-degree distributions and on the potential tension between the degree exponent ?, characterizing new connections (outgoing links), and the degree exponent ?_{KR}(r) dictated by the redirection mechanism. PMID:25493839

Jabr-Hamdan, Ameerah; Sun, Jie; Ben-Avraham, Daniel

2014-11-01

342

Ethernet Network Functionality Testing.  

E-print Network

?? Ethernet functionality testing as a generic term used for checking connectivity,throughput and capability to transfer packets over the network. Especially in the packet-switchenvironment, Ethernet… (more)

Mirza, Aamir Mehmood

2009-01-01

343

The Deep Space Network  

NASA Technical Reports Server (NTRS)

The various systems and subsystems are discussed for the Deep Space Network (DSN). A description of the DSN is presented along with mission support, program planning, facility engineering, implementation and operations.

1977-01-01

344

The expandable network disk  

E-print Network

This thesis presents a virtual disk cluster called END, the Expandable Network Disk. END aggregates storage on a cluster of servers into a single virtual disk. END's main goals are to offer good performance during normal ...

Muthitacharoen, Athicha, 1976-

2008-01-01

345

ENVIRONMENTAL LAW NETWORK  

E-print Network

ENVIRONMENTAL LAW NETWORK INTERNATIONAL R�SEAU INTERNATIONAL DE DROIT DE L´ENVIRONNEMENT INTERNATIONALES NETZWERK UMWELTRECHT EU Enforcement Policy of Community Environmental law as presented in the Commission Communication on implementing European Community Environmental law Marta Ballesteros The direct

Paris-Sud XI, Université de

346

Introduction to Network Security  

NSDL National Science Digital Library

Provided by Internet Security Company Interhack, and written by Matt Curtin, this sixteen-page document is available in HTML, PDF, and Postscript formats. The document includes some history of networking, as well as an introduction to TCP/IP and internetworking. The document then goes on to consider risk management, network threats, firewalls, and more special-purpose secure networking devices. According to the abstract, the author hopes that â??the reader will have a wider perspective on security in general, and better understand how to reduce and manage risk personally, at home, and in the workplace.â? This is a great resource for students and teachers of introductory computer network security and cyber security courses.

Curtin, Matt

347

Bioprinting: Functional droplet networks  

NASA Astrophysics Data System (ADS)

Tissue-mimicking printed networks of droplets separated by lipid bilayers that can be functionalized with membrane proteins are able to spontaneously fold and transmit electrical currents along predefined paths.

Durmus, Naside Gozde; Tasoglu, Savas; Demirci, Utkan

2013-06-01

348

Yeast Education Network  

NSDL National Science Digital Library

The Yeast Education Network provides a variety of resources to facilitate use of the budding yeast Saccharomyces cerevisiae in undergraduate science curricula. Laboratory, classroom, and computer-based activities can be used with college and advanced high school students.

349

International Cancer Screening Network  

Cancer.gov

Skip to Main Content Search International Cancer Screening Network Sponsored by the National Cancer Institute Working Together to Evaluate Cancer Screening and Improve Outcomes Internationally About the ICSN Overview Participating Countries Contact

350

Addition deletion networks  

NASA Astrophysics Data System (ADS)

We study structural properties of growing networks where both addition and deletion of nodes are possible. Our model network evolves via two independent processes. With rate r, a node is added to the system and this node links to a randomly selected existing node. With rate 1, a randomly selected node is deleted and its parent node inherits the links of its immediate descendants. We show that the in-component size distribution decays algebraically, ck ~ k-? as k ? ?. The exponent ? = 2 + (r - 1)-1 varies continuously with the addition rate r. Structural properties of the network including the height distribution, the diameter of the network, the average distance between two nodes and the fraction of dangling nodes are also obtained analytically. Interestingly, the deletion process leads to a giant hub, a single node with a macroscopic degree whereas all other nodes have a microscopic degree.

Ben-Naim, E.; Krapivsky, P. L.

2007-07-01

351

Honors Faculty Mentor Network  

E-print Network

-2007 #12;DAVID WILLIAMS, Dire DAVID WILLIAMS, Director dwilliam@uga.edu STEVE ELLIOTT-GOWER, Associate@uga.edu SMITH WYCKOFF, Graduate Assistant sw@uga.edu Faculty & Staff #12;Honors Faculty Mentor Network Table

Arnold, Jonathan

352

The Colombia Seismological Network  

NASA Astrophysics Data System (ADS)

The latest seismological equipment and data processing instrumentation installed at the Colombia Seismological Network (RSNC) are described. System configuration, network operation, and data management are discussed. The data quality and the new seismological products are analyzed. The main purpose of the network is to monitor local seismicity with a special emphasis on seismic activity surrounding the Colombian Pacific and Caribbean oceans, for early warning in case a Tsunami is produced by an earthquake. The Colombian territory is located at the South America northwestern corner, here three tectonic plates converge: Nazca, Caribbean and the South American. The dynamics of these plates, when resulting in earthquakes, is continuously monitored by the network. In 2012, the RSNC registered in 2012 an average of 67 events per day; from this number, a mean of 36 earthquakes were possible to be located well. In 2010 the network was also able to register an average of 67 events, but it was only possible to locate a mean of 28 earthquakes daily. This difference is due to the expansion of the network. The network is made up of 84 stations equipped with different kind of broadband 40s, 120s seismometers, accelerometers and short period 1s sensors. The signal is transmitted continuously in real-time to the Central Recording Center located at Bogotá, using satellite, telemetry, and Internet. Moreover, there are some other stations which are required to collect the information in situ. Data is recorded and processed digitally using two different systems, EARTHWORM and SEISAN, which are able to process and share the information between them. The RSNC has designed and implemented a web system to share the seismological data. This innovative system uses tools like Java Script, Oracle and programming languages like PHP to allow the users to access the seismicity registered by the network almost in real time as well as to download the waveform and technical details. The coverage of the RSNC network is presented along with the improvement in earthquake location and the quality of the data. New tools to calculate moment magnitude and focal mechanism are implemented as a result of the network expansion. The principal seismic sources in Colombia and the challenges for the future of the network are discussed.

Blanco Chia, J. F.; Poveda, E.; Pedraza, P.

2013-05-01

353

Evolution of networks  

Microsoft Academic Search

We review the recent fast progress in statistical physics of evolving\\u000anetworks. Interest has focused mainly on the structural properties of random\\u000acomplex networks in communications, biology, social sciences and economics. A\\u000anumber of giant artificial networks of such a kind came into existence\\u000arecently. This opens a wide field for the study of their topology, evolution,\\u000aand complex processes

S. N. Dorogovtsev; J. F. F. Mendes

2002-01-01

354

The VHN network  

Microsoft Academic Search

We describe VHN, the versatile home network, an EIA standard (EIA\\/CEA-851) developed with broad industry input, that.defines a home intranet. VHN ties together other home LAN, such as Ethernet or IEEE 802.11a, allowing any device on a home network to communicate with any other device. The VHN architecture implements a whole-home backbone, using IEEE 1394b, a long distance version of

S. G. Ungar

2002-01-01

355

Inferring Transcriptional Regulatory Network  

Microsoft Academic Search

\\u000a Genes are coordinately regulated and expressed as forming various transcriptional modules or networks to carry out complex\\u000a and condition-specific biological functions in living cells. In this chapter, we describe a series of new methodologies for\\u000a identifying transcriptional modules and regulatory networks and examining their evolutionarily conserved and divergent patterns\\u000a from gene expression and transcription factor data. The methods are based

Ming Zhan

356

Bolivian Seismic Network  

NASA Astrophysics Data System (ADS)

One of the biggest challenges into the Seismic Network of Bolivia, composed of seven stations, is to connect all the differents characteristic of them. The Observatory San Calixto, network operator, is one of the few private seismic observatories in the world and for this reason is working only with agreement support or extern cooperation. This problem needs a promptly solution to obtain data system more convenient, in a real time, more effective and compatible with a future extension network. Now, we have differences in the equipment and transmission too. Two of our network stations, are part of the IMS (International System of Data), the information are transmitted by telemetry way from Primary Station PS6 (LPAZ) to OSC, and then by Vsat to IMS and by optic fiber to AFTAC. The auxiliary seismic station AS08 (SIV) sends information to DASE France by satellite way, and then DASE transmits to the IMS, and to the OSC by Internet. Similar situation is used for another station: MOC. The data of the other four stations are transmitted by telemetry to the OSC center, but here the difference with the other stations is that they are working with analogy system. This network does not cover all the Bolivian territory for a completed monitoring of the seismic activity of the country. For this reason it is very important for Bolivia to extend the network with installation of other stations and a project for the characteristic compatibility (formats specially) of this news stations with the actual stations and temporally stations. Temporally stations are mainly used to support the network and to obtain the evaluation of micro activity in some areas that have a possible seismic threat and because of the actual network distribution where the activity is unknown for us.

Minaya, E.; Rougon, P.; Valero, D.; Fernandez, G.; Lazaro, E.; Cano, W.

2007-05-01

357

Phobos - Control network analysis  

NASA Technical Reports Server (NTRS)

Initial analysis of the Mariner 9 high resolution pictures of Phobos surface features has been completed. A control network of 38 landmarks has been established and used to determine the physical size, shape, orientation, libration, and topography properties of Phobos. The results verified the synchronous rotation of Phobos and revealed a libration of approximately 5 deg in the orbit plane of Phobos. A preliminary map of Phobos, based on the control network analysis, is given.

Duxbury, T. C.

1974-01-01

358

Underwater acoustic networks  

Microsoft Academic Search

With the advances in acoustic modem technology that enabled high-rate reliable communications, current research focuses on communication between various remote instruments within a network environment. Underwater acoustic (UWA) networks are generally formed by acoustically connected ocean-bottom sensors, autonomous underwater vehicles, and a surface station, which provides a link to an on-shore control center. While many applications require long-term monitoring of

Ethem M. Sozer; Milica Stojanovic; John G. Proakis

2000-01-01

359

Wireless Multimedia Sensor Networks  

Microsoft Academic Search

\\u000a The emergence of low-cost and mature technologies in wireless communication, visual sensor devices, and digital signal processing\\u000a facilitate of wireless multimedia sensor networks (WMSN). Like sensor networks which respond to sensory information such as\\u000a temperature and humidity, WMSN interconnects autonomous devices for capturing and processing video and audio sensory information.\\u000a This survey highlights the following topics (1) a summary of

Ivan Lee; William Shaw; Xiaoming Fan

360

Information Horizons in Networks  

Microsoft Academic Search

We investigate and quantify the interplay between topology and ability to\\u000asend specific signals in complex networks. We find that in a majority of\\u000ainvestigated real-world networks the ability to communicate is favored by the\\u000anetwork topology on small distances, but disfavored at larger distances. We\\u000afurther discuss how the ability to locate specific nodes can be improved if\\u000ainformation

A. Trusina; M. Rosvall; K. Sneppen

2004-01-01

361

Leaf Pack Network  

NSDL National Science Digital Library

The Leaf Pack Network (LPN) is a network of teachers and students investigating their local stream ecosystems by participating in the leaf pack experiment, which involves creating an artificial leaf pack (dry leaves in a mesh bag), immersing it in a stream for 3-4 weeks, and examining it for signs of aquatic insects as indicators of stream health. Participating classrooms share their data through the internet. This activity highlights the connection between streamside forests and the ecology of rivers and streams.

362

Networks of strong ties  

NASA Astrophysics Data System (ADS)

Social networks transmitting covert or sensitive information cannot use all ties for this purpose. Rather, they can only use a subset of ties that are strong enough to be “trusted”. This paper addresses whether it is still possible, under this restriction, for information to be transmitted widely and rapidly in social networks. We use transitivity as evidence of strong ties, requiring one or more shared contacts in order to count an edge as strong. We examine the effect of removing all non-transitive ties in two real social network data sets, imposing varying thresholds in the number of shared contacts. We observe that transitive ties occupy a large portion of the network and that removing all other ties, while causing some individuals to become disconnected, preserves the majority of the giant connected component. Furthermore, the average shortest path, important for the rapid diffusion of information, increases only slightly relative to the original network. We also evaluate the cost of forming transitive ties by modeling a random graph composed entirely of closed triads and comparing its connectivity and average shortest path with the equivalent Erdös-Renyi random graph. Both the empirical study and random model point to a robustness of strong ties with respect to the connectivity and small world property of social networks.

Shi, Xiaolin; Adamic, Lada A.; Strauss, Martin J.

2007-05-01

363

Transcriptional network classifiers  

PubMed Central

Background Gene interactions play a central role in transcriptional networks. Many studies have performed genome-wide expression analysis to reconstruct regulatory networks to investigate disease processes. Since biological processes are outcomes of regulatory gene interactions, this paper develops a system biology approach to infer function-dependent transcriptional networks modulating phenotypic traits, which serve as a classifier to identify tissue states. Due to gene interactions taken into account in the analysis, we can achieve higher classification accuracy than existing methods. Results Our system biology approach is carried out by the Bayesian networks framework. The algorithm consists of two steps: gene filtering by Bayes factor followed by collinearity elimination via network learning. We validate our approach with two clinical data. In the study of lung cancer subtypes discrimination, we obtain a 25-gene classifier from 111 training samples, and the test on 422 independent samples achieves 95% classification accuracy. In the study of thoracic aortic aneurysm (TAA) diagnosis, 61 samples determine a 34-gene classifier, whose diagnosis accuracy on 33 independent samples achieves 82%. The performance comparisons with three other popular methods, PCA/LDA, PAM, and Weighted Voting, confirm that our approach yields superior classification accuracy and a more compact signature. Conclusions The system biology approach presented in this paper is able to infer function-dependent transcriptional networks, which in turn can classify biological samples with high accuracy. The validation of our classifier using clinical data demonstrates the promising value of our proposed approach for disease diagnosis. PMID:19761563

Chang, Hsun-Hsien; Ramoni, Marco F

2009-01-01

364

Network reconfiguration and neuronal plasticity in rhythm-generating networks.  

PubMed

Neuronal networks are highly plastic and reconfigure in a state-dependent manner. The plasticity at the network level emerges through multiple intrinsic and synaptic membrane properties that imbue neurons and their interactions with numerous nonlinear properties. These properties are continuously regulated by neuromodulators and homeostatic mechanisms that are critical to maintain not only network stability and also adapt networks in a short- and long-term manner to changes in behavioral, developmental, metabolic, and environmental conditions. This review provides concrete examples from neuronal networks in invertebrates and vertebrates, and illustrates that the concepts and rules that govern neuronal networks and behaviors are universal. PMID:21856733

Koch, Henner; Garcia, Alfredo J; Ramirez, Jan-Marino

2011-12-01

365

Social Network Visualization in Epidemiology  

PubMed Central

Epidemiological investigations and interventions are increasingly focusing on social networks. Two aspects of social networks are relevant in this regard: the structure of networks and the function of networks. A better understanding of the processes that determine how networks form and how they operate with respect to the spread of behavior holds promise for improving public health. Visualizing social networks is a key to both research and interventions. Network images supplement statistical analyses and allow the identification of groups of people for targeting, the identification of central and peripheral individuals, and the clarification of the macro-structure of the network in a way that should affect public health interventions. People are inter-connected and so their health is inter-connected. Inter-personal health effects in social networks provide a new foundation for public health. PMID:22544996

Christakis, Nicholas A.; Fowler, James H.

2010-01-01

366

LINCS: Livermore's network architecture. [Octopus computing network  

SciTech Connect

Octopus, a local computing network that has been evolving at the Lawrence Livermore National Laboratory for over fifteen years, is currently undergoing a major revision. The primary purpose of the revision is to consolidate and redefine the variety of conventions and formats, which have grown up over the years, into a single standard family of protocols, the Livermore Interactive Network Communication Standard (LINCS). This standard treats the entire network as a single distributed operating system such that access to a computing resource is obtained in a single way, whether that resource is local (on the same computer as the accessing process) or remote (on another computer). LINCS encompasses not only communication but also such issues as the relationship of customer to server processes and the structure, naming, and protection of resources. The discussion includes: an overview of the Livermore user community and computing hardware, the functions and structure of each of the seven layers of LINCS protocol, the reasons why we have designed our own protocols and why we are dissatisfied by the directions that current protocol standards are taking.

Fletcher, J.G.

1982-01-01

367

The Complexity of Terrorist Networks  

NASA Astrophysics Data System (ADS)

Complexity science affords a number of novel tools for examining terrorism, particularly network analysis and NK-Boolean fitness landscapes. The following paper explores various aspects of terrorist networks which can be illuminated through applications of non-linear dynamical systems modeling to terrorist network structures. Of particular interest are some of the emergent properties of terrorist networks as typified by the 9-11 hijackers network, properties of centrality, hierarchy and distance, as well as ways in which attempts to disrupt the transmission of information through terrorist networks may be expected to produce greater or lesser levels of fitness in those organizations.

Fellman, Philip Vos

368

Multiple network interface core apparatus and method  

DOEpatents

A network interface controller and network interface control method comprising providing a single integrated circuit as a network interface controller and employing a plurality of network interface cores on the single integrated circuit.

Underwood, Keith D. (Albuquerque, NM); Hemmert, Karl Scott (Albuquerque, NM)

2011-04-26

369

Security and privacy in emerging wireless networks [Guest Editorial  

Microsoft Academic Search

Rapid advances in wireless ad hoc networking have extended its application from mobile ad hoc networks and wireless sensor networks to emerging wireless networks including wireless mesh networks, delay-tolerant networks, vehicular networks, and urban sensing networks. While facilitating ubiquitous network access as well as social interactions, these emerging networks are particularly vulnerable to numerous privacy and security threats. For example,

Guohong Cao; J.-P. Hubaux; Yongdae Kim; Yanchao Zhang

2010-01-01

370

Interictal networks in magnetoencephalography.  

PubMed

Epileptic networks involve complex relationships across several brain areas. Such networks have been shown on intracerebral EEG (stereotaxic EEG, SEEG), an invasive technique. Magnetoencephalography (MEG) is a noninvasive tool, which was recently proven to be efficient for localizing the generators of epileptiform discharges. However, despite the importance of characterizing non-invasively network aspects in partial epilepsies, only few studies have attempted to retrieve fine spatiotemporal dynamics of interictal discharges with MEG. Our goal was to assess the relevance of magnetoencephalography for detecting and characterizing the brain networks involved in interictal epileptic discharges. We propose here a semi-automatic method based on independent component analysis (ICA) and on co-occurrence of events across components. The method was evaluated in a series of seven patients by comparing its results with networks identified in SEEG. On both MEG and SEEG, we found that interictal discharges can involve remote regions which are acting in synchrony. More regions were identified in SEEG (38 in total) than in MEG (20). All MEG regions were confirmed by SEEG when an electrode was present in the vicinity. In all patients, at least one region could be identified as leading according to our criteria. A majority (71%) of MEG leaders were confirmed by SEEG. We have therefore shown that MEG measurements can extract a significant proportion of the networks visible in SEEG. This suggests that MEG can be a useful tool for defining noninvasively interictal epileptic networks, in terms of regions and patterns of connectivity, in search for a "primary irritative zone". PMID:24105895

Malinowska, Urszula; Badier, Jean-Michel; Gavaret, Martine; Bartolomei, Fabrice; Chauvel, Patrick; Bénar, Christian-George

2014-06-01

371

Network Adaptive Deadband: NCS Data Flow Control for Shared Networks  

PubMed Central

This paper proposes a new middleware solution called Network Adaptive Deadband (NAD) for long time operation of Networked Control Systems (NCS) through the Internet or any shared network based on IP technology. The proposed middleware takes into account the network status and the NCS status, to improve the global system performance and to share more effectively the network by several NCS and sensor/actuator data flows. Relationship between network status and NCS status is solved with a TCP-friendly transport flow control protocol and the deadband concept, relating deadband value and transmission throughput. This creates a deadband-based flow control solution. Simulation and experiments in shared networks show that the implemented network adaptive deadband has better performance than an optimal constant deadband solution in the same circumstances. PMID:23208556

Díaz-Cacho, Miguel; Delgado, Emma; Prieto, José A. G.; López, Joaquín

2012-01-01

372

Spatial Network Services in Location-Aware Sensor Networks.  

E-print Network

??Emerging technologies in low-power microsensors, actuators, embedded processors, and RF radios have facilitated the deployment of large-scale sensor networks and enabled such networks to monitor… (more)

Xu, Yingqi

2006-01-01

373

Taming the IXP Network Processor Network Speed Technologies, Inc  

E-print Network

@network-speed.com Matthias Blume Toyota Technological Institute at Chicago blume@tti-c.org ABSTRACT We compile Nova, a new S Figure 1: Micro-engine architecture when processing data at gigabit line rates, network processors

Blume, Matthias

374

Investigating the validity of current network analysis on static conglomerate networks by protein network stratification  

PubMed Central

Background A molecular network perspective forms the foundation of systems biology. A common practice in analyzing protein-protein interaction (PPI) networks is to perform network analysis on a conglomerate network that is an assembly of all available binary interactions in a given organism from diverse data sources. Recent studies on network dynamics suggested that this approach might have ignored the dynamic nature of context-dependent molecular systems. Results In this study, we employed a network stratification strategy to investigate the validity of the current network analysis on conglomerate PPI networks. Using the genome-scale tissue- and condition-specific proteomics data in Arabidopsis thaliana, we present here the first systematic investigation into this question. We stratified a conglomerate A. thaliana PPI network into three levels of context-dependent subnetworks. We then focused on three types of most commonly conducted network analyses, i.e., topological, functional and modular analyses, and compared the results from these network analyses on the conglomerate network and five stratified context-dependent subnetworks corresponding to specific tissues. Conclusions We found that the results based on the conglomerate PPI network are often significantly different from those of context-dependent subnetworks corresponding to specific tissues or conditions. This conclusion depends neither on relatively arbitrary cutoffs (such as those defining network hubs or bottlenecks), nor on specific network clustering algorithms for module extraction, nor on the possible high false positive rates of binary interactions in PPI networks. We also found that our conclusions are likely to be valid in human PPI networks. Furthermore, network stratification may help resolve many controversies in current research of systems biology. PMID:20846443

2010-01-01

375

Application of Wavelet Neural-Networks in Wireless Sensor Networks  

Microsoft Academic Search

Some of the algorithms developed within the artificial neural-networks tradition can be easily adopted to wireless sensor network platforms and in the same time they can meet the requirements for sensor networks like: simple parallel distributed computation, distributed storage, data robustness and auto-classification of sensor readings. Dimensionality reduction, obtained simply from the outputs of the neural-networks clustering algorithms, leads to

Andrea Kulakov; Danco Davcev; Goran Trajkovski

2005-01-01

376

MMS: An autonomic network-layer foundation for network management  

Microsoft Academic Search

Abstract—Networks cannot be managed,without communi- cation among,geographically distributed network devices and control agents. Unfortunately, computer networks today lack an autonomic mechanism that enables such communications, and the stopgap solutions used in practice are seriously flawed. To address the problem, this paper presents the design and implementation of the Meta-Management System (MMS), a network-layer subsystem that provides robust and,universal support for

Hemant Gogineni; Albert G. Greenberg; David A. Maltz; Tze Sing Eugene Ng; Hong Yan; Hui Zhang

2010-01-01

377

Bayesian Network Analysis of Signaling Networks: A Primer  

NSDL National Science Digital Library

High-throughput proteomic data can be used to reveal the connectivity of signaling networks and the influences between signaling molecules. We present a primer on the use of Bayesian networks for this task. Bayesian networks have been successfully used to derive causal influences among biological signaling molecules (for example, in the analysis of intracellular multicolor flow cytometry). We discuss ways to automatically derive a Bayesian network model from proteomic data and to interpret the resulting model.

Dana Pe'er (Harvard Medical School; Department of Genetics REV)

2005-04-26

378

Structural and magnetic properties of Ge0.7Mn0.3 thin films Sung-Kyu Kim a  

E-print Network

fabricated on Al2O3 (0001) and glass substrates at growth temperatures ranging from room temperature to 500: Semiconductors Deposition process Sputtering Magnetic properties and measurements Ge0.7Mn0.3 thin films were °C by a radio frequency magnetron sputtering. We found that the Ge0.7Mn0.3 thin films showed

Jo, Moon-Ho

379

Physical Layout Automation for System-On-Packages Ramprasad Ravichandran, Jacob Minz, Mohit Pathak, Siddharth Easwar, and Sung Kyu Lim  

E-print Network

the traditional multi-layer PCB or MCM packaging. In this paper, we present the first 3D physical design, the existing design tools for PCB or MCM packaging [7,8,9] can not be used directly for the design of SOP algorithms targeting SOP technology. 3D partitioning divides the input design into multiple layers. 3D

Lim, Sung Kyu

380

GaN light-emitting triodes for high-efficiency hole injection and light Jong Kyu Kima,*  

E-print Network

attention for applications such as chemical and biological detection systems, water and air sterilization of the most important challenges especially for deep UV LEDs ( , as shown in the Fig. 1 (a). The tunneling probability of holes through the EBL is low due to a high

Jiang, Hongxing

381

Theorizing Network-Centric Activity in Education  

ERIC Educational Resources Information Center

Networks and network-centric activity are increasingly prevalent in schools and school districts. In addition to ubiquitous social network tools like Facebook and Twitter, educational leaders deal with a wide variety of network organizational forms that include professional development, advocacy, informational networks and network-centric reforms.…

HaLevi, Andrew

2011-01-01

382

Geometric Interpretation of Gene Coexpression Network Analysis  

Microsoft Academic Search

The merging of network theory and microarray data analysis techniques has spawned a new field: gene coexpression network analysis. While network methods are increasingly used in biology, the network vocabulary of computational biologists tends to be far more limited than that of, say, social network theorists. Here we review and propose several potentially useful network concepts. We take advantage of

Steve Horvath; Jun Dong

2008-01-01

383

Fragile Networks: Identifying Vulnerabilities and Synergies  

E-print Network

Fragile Networks: Identifying Vulnerabilities and Synergies in an Uncertain Age Anna Nagurney and Acquisitions, Network Integration, and Synergies #12;Part I #12;Why Study Fragile Networks? Networks provide of catastrophic events that have drawn attention to network vulnerability and fragility. Since many networks

Nagurney, Anna

384

Fragile Networks: Identifying Vulnerabilities and Synergies  

E-print Network

Fragile Networks: Identifying Vulnerabilities and Synergies in an Uncertain World Pre and Acquisitions, Network Integration, and Synergies #12;Module I #12;Why Study Fragile Networks? Networks provide of catastrophic events that have drawn attention to network vulnerability and fragility. Since many networks

Nagurney, Anna

385

Current approaches to gene regulatory network modelling  

Microsoft Academic Search

Many different approaches have been developed to model and simulate gene regulatory networks. We proposed the following categories for gene regulatory network models: network parts lists, network topology models, network control logic models, and dynamic models. Here we will describe some examples for each of these categories. We will study the topology of gene regulatory networks in yeast in more

Thomas Schlitt; Alvis Brazma

2007-01-01

386

Social Network Infiltration  

NASA Astrophysics Data System (ADS)

Social networks are websites (or software that distributes media online) where users can distribute content to either a list of friends on that site or to anyone who surfs onto their page, and where those friends can interact and discuss the content. By linking to friends online, the users’ personal content (pictures, songs, favorite movies, diaries, websites, and so on) is dynamically distributed, and can "become viral", that is, get spread rapidly as more people see it and spread it themselves. Social networks are immensely popular around the planet, especially with younger users. The biggest social networks are Facebook and MySpace; an IYA2009 user already exists on Facebook, and one will be created for MySpace (in fact, several NASA satellites such as GLAST and Swift already have successful MySpace pages). Twitter is another network where data distribution is more limited; it is more like a mini-blog, but is very popular. IYA2009 already has a Twitter page, and will be updated more often with relevant information. In this talk I will review the existing social networks, show people how and why they are useful, and give them the tools they need to contribute meaningfully to IYA's online reach.

Plait, Philip

2008-05-01

387

Uniformly sparse neural networks  

NASA Astrophysics Data System (ADS)

Application of neural networks to problems with a large number of sensory inputs is severely limited when the processing elements (PEs) need to be fully connected. This paper presents a new network model in which a trade off between the number of connections to a node and the number of processing layers can be made. This trade off is an important issue in the VLSI implementation of neural networks. The performance and capability of a hierarchical pyramidal network architecture of limited fan-in PE layers is analyzed. Analysis of this architecture requires the development of a new learning rule, since each PE has access to limited information about the entire network input. A spatially local unsupervised training rule is developed in which each PE optimizes the fraction of its output variance contributed by input correlations, resulting in PEs behaving as adaptive local correlation detectors. It is also shown that the output of a PE optimally represents the mutual information among the inputs to that PE. Applications of the developed model in image compression and motion detection are presented.

Haghighi, Siamack

1992-07-01

388

Quantifying loopy network architectures.  

PubMed

Biology presents many examples of planar distribution and structural networks having dense sets of closed loops. An archetype of this form of network organization is the vasculature of dicotyledonous leaves, which showcases a hierarchically-nested architecture containing closed loops at many different levels. Although a number of approaches have been proposed to measure aspects of the structure of such networks, a robust metric to quantify their hierarchical organization is still lacking. We present an algorithmic framework, the hierarchical loop decomposition, that allows mapping loopy networks to binary trees, preserving in the connectivity of the trees the architecture of the original graph. We apply this framework to investigate computer generated graphs, such as artificial models and optimal distribution networks, as well as natural graphs extracted from digitized images of dicotyledonous leaves and vasculature of rat cerebral neocortex. We calculate various metrics based on the asymmetry, the cumulative size distribution and the Strahler bifurcation ratios of the corresponding trees and discuss the relationship of these quantities to the architectural organization of the original graphs. This algorithmic framework decouples the geometric information (exact location of edges and nodes) from the metric topology (connectivity and edge weight) and it ultimately allows us to perform a quantitative statistical comparison between predictions of theoretical models and naturally occurring loopy graphs. PMID:22701593

Katifori, Eleni; Magnasco, Marcelo O

2012-01-01

389

Complex aperture networks  

NASA Astrophysics Data System (ADS)

A complex network approach is proposed for studying the shear behavior of a rough rock joint. Similarities between aperture profiles are established, and a functional complex network-in each shear displacement-is constructed in two directions: parallel and perpendicular to the shear direction. We find that the growth of the clustering coefficient and that of the number of edges are approximately scaled with the development of shear strength and hydraulic conductivity, which could possibly be utilized to estimate and formulate a friction law and the evolution of shear distribution over asperities. Moreover, the frictional interface is mapped in the global-local parameter space of the corresponding functional friction network, showing the evolution path and, eventually, the residual stage. Furthermore, we show that with respect to shear direction, parallel aperture patches are more adaptable to environmental stimuli than perpendicular profiles. We characterize the pure-contact profiles using the same approach. Unlike the first case, the later networks show a growing trend while in the residual stage; a saturation of links is encoded in contact networks.

Ghaffari, H. O.; Sharifzadeh, M.; Young, R. Paul

2013-02-01

390

Networks of Emotion Concepts  

PubMed Central

The aim of this work was to study the similarity network and hierarchical clustering of Finnish emotion concepts. Native speakers of Finnish evaluated similarity between the 50 most frequently used Finnish words describing emotional experiences. We hypothesized that methods developed within network theory, such as identifying clusters and specific local network structures, can reveal structures that would be difficult to discover using traditional methods such as multidimensional scaling (MDS) and ordinary cluster analysis. The concepts divided into three main clusters, which can be described as negative, positive, and surprise. Negative and positive clusters divided further into meaningful sub-clusters, corresponding to those found in previous studies. Importantly, this method allowed the same concept to be a member in more than one cluster. Our results suggest that studying particular network structures that do not fit into a low-dimensional description can shed additional light on why subjects evaluate certain concepts as similar. To encourage the use of network methods in analyzing similarity data, we provide the analysis software for free use (http://www.becs.tkk.fi/similaritynets/). PMID:22276099

Toivonen, Riitta; Kivelä, Mikko; Saramäki, Jari; Viinikainen, Mikko; Vanhatalo, Maija; Sams, Mikko

2012-01-01

391

Tidal networks 2. Watershed delineation and comparative network morphology  

E-print Network

of three, we quantify various tidal network properties including common power law relationships which have common power law relationships quantified for terrestrial systems to tidal systems and use these analysesTidal networks 2. Watershed delineation and comparative network morphology Andrea Rinaldo,1 Sergio

Fagherazzi, Sergio

392

Validating Large Scale Networks Using Temporary Local Scale Networks  

Technology Transfer Automated Retrieval System (TEKTRAN)

The USDA NRCS Soil Climate Analysis Network and NOAA Climate Reference Networks are nationwide meteorological and land surface data networks with soil moisture measurements in the top layers of soil. There is considerable interest in scaling these point measurements to larger scales for validating ...

393

Networks and Learning: Communities, Practices and the Metaphor of Networks  

ERIC Educational Resources Information Center

This article argues that the use of the network metaphor can link together various different aspects of research into the use of advanced learning technologies based on computer networks. The idea of networked learning has become commonplace as an alternative to e-learning that stresses the interaction of learners, tutors and resources through…

Jones, Chris

2004-01-01

394

A new transient network model for associative polymer networks  

Microsoft Academic Search

A new model for the linear viscoelastic behavior of polymer networks is developed. In this model the polymer system is described as a network of spring segments connected via sticky points (as in the Lodge model). [Lodge, A. S., “A network theory of flow birefringence and stress in concentrated polymer solutions,” Trans. Faraday Soc. 52, 120–130 (1956).] An important extension

R. H. W. Wientjes; R. J. J. Jongschaap; M. H. G. Duits; J. Mellema

1999-01-01

395

Promoting Social Network Awareness: A Social Network Monitoring System  

ERIC Educational Resources Information Center

To increase communication and collaboration opportunities, members of a community must be aware of the social networks that exist within that community. This paper describes a social network monitoring system--the KIWI system--that enables users to register their interactions and visualize their social networks. The system was implemented in a…

Cadima, Rita; Ferreira, Carlos; Monguet, Josep; Ojeda, Jordi; Fernandez, Joaquin

2010-01-01

396

Improving network lifetime with mobile wireless sensor networks  

Microsoft Academic Search

Sensors are used to monitor and control the physical environment. In mobile sensor networks, nodes can self-propel via springs, wheels, or they can be attached to transporters, such as vehicles. Sensors have limited energy supply and the sensor network is expected to be functional for a long time, so optimizing the energy consumption to prolong the network lifetime becomes an

Yinying Yang; Mirela I. Fonoage; Mihaela Cardei

2010-01-01

397

Mobile Network Management and Robust Spatial Retreats via Network Dynamics  

E-print Network

1 Mobile Network Management and Robust Spatial Retreats via Network Dynamics Ke Ma, Yanyong Zhang., Piscataway, NJ 08854. Abstract-- The mobility provided by mobile ad hoc and sen- sor networks will facilitate new mobility-oriented services. Recent work has demonstrated that, for many issues, mobility

Zhang, Yanyong

398

Incorporating existing network information into gene network inference.  

PubMed

One methodology that has met success to infer gene networks from gene expression data is based upon ordinary differential equations (ODE). However new types of data continue to be produced, so it is worthwhile to investigate how to integrate these new data types into the inference procedure. One such data is physical interactions between transcription factors and the genes they regulate as measured by ChIP-chip or ChIP-seq experiments. These interactions can be incorporated into the gene network inference procedure as a priori network information. In this article, we extend the ODE methodology into a general optimization framework that incorporates existing network information in combination with regularization parameters that encourage network sparsity. We provide theoretical results proving convergence of the estimator for our method and show the corresponding probabilistic interpretation also converges. We demonstrate our method on simulated network data and show that existing network information improves performance, overcomes the lack of observations, and performs well even when some of the existing network information is incorrect. We further apply our method to the core regulatory network of embryonic stem cells utilizing predicted interactions from two studies as existing network information. We show that including the prior network information constructs a more closely representative regulatory network versus when no information is provided. PMID:19710931

Christley, Scott; Nie, Qing; Xie, Xiaohui

2009-01-01

399

Network coding in duty-cycled sensor networks  

Microsoft Academic Search

Network coding and duty-cycling are two popular techniques for saving energy in wireless adhoc and sensor networks. To the best of our knowledge, the idea to combine these two techniques, for more aggressive energy savings, has not been explored. One explanation is that these techniques achieve energy efficiency through conflicting means, e.g., network coding saves energy by exploiting overhearing, whereas

Roja Chandanala; Radu Stoleru

2010-01-01

400

Controlling across complex networks - Emerging links between networks and control  

Microsoft Academic Search

This paper discusses the interplay between networks and control systems. As we gain more understanding about the structure and dynamics of physical networks, their effects on the performance of closed-loop control systems, as well as the ability to control such networks, provide fertile areas of research. The paper reviews such research with special emphasis on the connectivity and delays in

A. Clauset; H. G. Tanner; Chaouki T. Abdallah; Raymond H. Byrne

2008-01-01

401

Configuring Networks and Devices with Simple Network Management Protocol (SNMP)  

Microsoft Academic Search

This document is written for readers interested in the Internet Standard Management Framework and its protocol, the Simple Network Management Protocol (SNMP). In particular, it offers guidance in the effective use of SNMP for configuration management. This information is relevant to vendors that build network elements, management application developers, and those that acquire and deploy this technology in their networks.

D. Partain; J. Saperia; W. Tackabury

402

Internet network management using the simple network management protocol  

Microsoft Academic Search

The simple network management protocol (SNMP) is an application protocol that allows logically remote users to inspect or alter management variables. The SNMP is typically used for the management network of networks, or internets, which utilize the TCP\\/IP protocol suite. A brief introduction to the SNMP is presented, and its architectural principles are described. The transport paradigm and SNMP applications

Jeffrey D. Case; James R. Davin; Mark S. Fedor; Martin L. Schoffstall

1989-01-01

403

Do You Lock Your Network Doors? Some Network Management Precautions.  

ERIC Educational Resources Information Center

Discusses security problems and solutions for networked organizations with Internet connections. Topics include access to private networks from electronic mail information; computer viruses; computer software; corporate espionage; firewalls, that is computers that stand between a local network and the Internet; passwords; and physical security.…

Neray, Phil

1997-01-01

404

CRCHD National Outreach Network (NON)  

Cancer.gov

NATIONAL OUTREACH NETWORK (NON) Overview The National Cancer Institute’s (NCI) National Outreach Network is a multidisciplinary program that bridges NCI-supported outreach and community education efforts with cancer health disparities research and

405

Local Area Networks (The Printout).  

ERIC Educational Resources Information Center

Describes the Local Area Network (LAN), a project in which students used LAN-based word processing and electronic mail software as the center of a writing process approach. Discusses the advantages and disadvantages of networking. (MM)

Aron, Helen; Balajthy, Ernest

1989-01-01

406

Huge networks, tiny faulty nodes  

E-print Network

Can one build, and efficiently use, networks of arbitrary size and topology using a "standard" node whose resources, in terms of memory and reliability, do not need to scale up with the complexity and size of the network? ...

Peserico, Enoch (Peserico Stecchini Negri de Salvi)

2007-01-01

407

National Network for Immunization Information  

MedlinePLUS

The National Network for Immunization Information (NNii) provides up-to-date, science-based information to healthcare professionals, the media, and the ... Fever Varicella (Chickenpox) Yellow Fever © Copyright 2010. National Network for Immunization Information (NNii). The information contained in ...

408

Weight-Control Information Network  

MedlinePLUS

... Facebook Welcome to WIN The Weight-control Information Network provides the general public, health professionals, the media, ... niddk.nih.gov ; or write Weight-control Information Network, 1 WIN Way, Bethesda, MD 20892–3665. Last ...

409

Intervention in gene regulatory networks  

E-print Network

In recent years Boolean Networks (BN) and Probabilistic Boolean Networks (PBN) have become popular paradigms for modeling gene regulation. A PBN is a collection of BNs in which the gene state vector transitions according to the rules of one...

Choudhary, Ashish

2006-10-30

410

Onion structure and network robustness  

E-print Network

In a recent work [Proc. Natl. Acad. Sci. USA 108, 3838 (2011)], Schneider et al. proposed a new measure for network robustness and investigated optimal networks with respect to this quantity. For networks with a power-law degree distribution, the optimized networks have an onion structure-high-degree vertices forming a core with radially decreasing degrees and an over-representation of edges within the same radial layer. In this paper we relate the onion structure to graphs with good expander properties (another characterization of robust network) and argue that networks of skewed degree distributions with large spectral gaps (and thus good expander properties) are typically onion structured. Furthermore, we propose a generative algorithm producing synthetic scale-free networks with onion structure, circumventing the optimization procedure of Schneider et al. We validate the robustness of our generated networks against malicious attacks and random removals.

Wu, Zhi-Xi; 10.1103/PhysRevE.84.026106

2011-01-01

411

Network coding for anonymous broadcast  

E-print Network

This thesis explores the use of network coding for anonymous broadcast. Network coding, the technique of transmitting or storing mixtures of messages rather than individual messages, can provide anonymity with its mixing ...

Sergeev, Ivan A

2013-01-01

412

JAMMING COMMUNICATION NETWORKS UNDER COMPLETE ...  

E-print Network

This paper describes a problem of interdicting/jamming wireless communi- ... Jamming communication networks is an important problem but has ...... On connectivity in ad hoc networks under jamming using directional antennas and mobility,.

2007-02-08

413

Meteorological applications surface network of  

E-print Network

Meteorological applications of a surface network of Global Positioning System receivers Siebren de network of Global Positioning System receivers Meteorologische toepassingen van een grondnetwerk van Global Positioning System ontvangers Proefschrift ter verkrijging van de graad doctor op gezag van de

Stoffelen, Ad

414

Network Coding: Exploiting Broadcast and  

E-print Network

Network Coding: Exploiting Broadcast and Superposition in Wireless Networks Jasper Goseling #12 : uur door Jasper GOSELING, elektrotechnisch ingenieur, geboren te Enschede. #12;Dit proefschri a pleasure. Jasper Goseling Enschede, October . #12;#12;Contents Introduction . Challenges in Wireless

Boucherie, Richard J.

415

Video Communication Networks Dan Schonfeld  

E-print Network

Video Communication Networks Dan Schonfeld Multimedia Communications Laboratory Department Chicago, IL 60607-7053 ds@ece.uic.edu Abstract In this presentation, a broad overview of video communication networks is provided. Numerous video communication applications are currently being developed

Schonfeld, Dan

416

Network-dosage compensation topologies as recurrent network motifs in natural gene networks  

PubMed Central

Background Global noise in gene expression and chromosome duplication during cell-cycle progression cause inevitable fluctuations in the effective number of copies of gene networks in cells. These indirect and direct alterations of network copy numbers have the potential to change the output or activity of a gene network. For networks whose specific activity levels are crucial for optimally maintaining cellular functions, cells need to implement mechanisms to robustly compensate the effects of network dosage fluctuations. Results Here, we determine the necessary conditions for generalized N-component gene networks to be network-dosage compensated and show that the compensation mechanism can robustly operate over large ranges of gene expression levels. Furthermore, we show that the conditions that are necessary for network-dosage compensation are also sufficient. Finally, using genome-wide protein-DNA and protein-protein interaction data, we search the yeast genome for the abundance of specific dosage-compensation motifs and show that a substantial percentage of the natural networks identified contain at least one dosage-compensation motif. Conclusions Our results strengthen the hypothesis that the special network topologies that are necessary for network-dosage compensation may be recurrent network motifs in eukaryotic genomes and therefore may be an important design principle in gene network assembly in cells. PMID:24929807

2014-01-01

417

Wireless mesh networks: a survey  

Microsoft Academic Search

Wireless mesh networks (WMNs) consist of mesh routers and mesh clients, where mesh routers have minimal mobi- lity and form the backbone of WMNs. They provide network access for both mesh and conventional clients. The inte- gration of WMNs with other networks such as the Internet, cellular, IEEE 802.11, IEEE 802.15, IEEE 802.16, sensor networks, etc., can be accomplished through

Ian F. Akyildiz; Xudong Wang; Weilin Wang

2005-01-01

418

Network management research in ATDNet  

Microsoft Academic Search

The Advanced Technology Demonstration Network (ATDNet) is a major testbed facility established by DARPA and other U.S. government agencies to conduct network and applications research on the next generation of high speed ATM\\/SONET networks. This article presents the approaches and results of our work in network management on ATDNet. The research addresses different aspects of next-generation systems design, including integrated

R. Doverspike; M. Maeda; S. Narain; J. Pastor; Chien-Chung Shen; N. Stoffel; Yukun Tsai; B. Wilson

1996-01-01

419

The All Sky Camera Network  

NSDL National Science Digital Library

In 2001, the All Sky Camera Network came to life as an outreach program to connect the Denver Museum of Nature and Science (DMNS) exhibit Space Odyssey with Colorado schools. The network is comprised of cameras placed strategically at schools throughout Colorado to capture fireballs--rare events that produce meteorites. Students involved in the network participate in an authentic, inquiry-based experience by tracking meteor events. This article discusses the past, present, and future of the All Sky Camera Network.

Caldwell, Andy

2005-02-01

420

Inference Networks for Document Retrieval  

Microsoft Academic Search

The use of inference networks to support document retrieval is introduced. A network-basead retrieval model is described and compared to conventional probabilis- tic and Boolean models. Network representations have been used in information retrieval since at least the early 1960's. Networks have been used to support diverse retrieval functions, including browsing (TC89), document clustering (CroSO), spreading activation search (CK87), support

Howard R. Turtle; W. Bruce Croft

1990-01-01

421

Programmable multimode quantum networks  

PubMed Central

Entanglement between large numbers of quantum modes is the quintessential resource for future technologies such as the quantum internet. Conventionally, the generation of multimode entanglement in optics requires complex layouts of beamsplitters and phase shifters in order to transform the input modes into entangled modes. Here we report the highly versatile and efficient generation of various multimode entangled states with the ability to switch between different linear optics networks in real time. By defining our modes to be combinations of different spatial regions of one beam, we may use just one pair of multi-pixel detectors in order to measure multiple entangled modes. We programme virtual networks that are fully equivalent to the physical linear optics networks they are emulating. We present results for N=2 up to N=8 entangled modes here, including N=2, 3, 4 cluster states. Our approach introduces the highly sought after attributes of flexibility and scalability to multimode entanglement. PMID:22929783

Armstrong, Seiji; Morizur, Jean-François; Janousek, Jiri; Hage, Boris; Treps, Nicolas; Lam, Ping Koy; Bachor, Hans-A.

2012-01-01

422

Neighborhood Environmental Watch Network  

SciTech Connect

The Neighborhood Environmental Watch Network (NEWNET) is a regional network of environmental monitoring stations and a data archival center that supports collaboration between communities, industry, and government agencies to solve environmental problems. The stations provide local displays of measurements for the public and transmit measurements via satellite to a central site for archival and analysis. Station managers are selected from the local community and trained to support the stations. Archived data and analysis tools are available to researchers, educational institutions, industrial collaborators, and the public across the nation through a communications network. Los Alamos National Laboratory and the Environmental Protection Agency have developed a NEWNET pilot program for the Department of Energy. The pilot program supports monitoring stations in Nevada, Arizona, Utah, Wyoming, and California. Additional stations are being placed in Colorado and New Mexico. Pilot stations take radiological and meteorological measurements. Other measurements are possible by exchanging sensors.

Sanders, L.D.

1993-10-01

423

The malignant social network  

PubMed Central

Tumors contain a vastly complicated cellular network that relies on local communication to execute malignant programs. The molecular cues that are involved in cell-cell adhesion orchestrate large-scale tumor behaviors such as proliferation and invasion. We have recently begun to appreciate that many tumors contain a high degree of cellular heterogeneity and are organized in a cellular hierarchy, with a cancer stem cell (CSC) population identified at the apex in multiple cancer types. CSCs reside in unique microenvironments or niches that are responsible for directing their behavior through cellular interactions between CSCs and stromal cells, generating a malignant social network. Identifying cell-cell adhesion mechanisms in this network has implications for the basic understanding of tumorigenesis and the development of more effective therapies. In this review, we will discuss our current understanding of cell-cell adhesion mechanisms used by CSCs and how these local interactions have global consequences for tumor biology. PMID:22796941

Hale, James S.; Li, Meizhang; Lathia, Justin D.

2012-01-01

424

Hyperbolic Hopfield neural networks.  

PubMed

In recent years, several neural networks using Clifford algebra have been studied. Clifford algebra is also called geometric algebra. Complex-valued Hopfield neural networks (CHNNs) are the most popular neural networks using Clifford algebra. The aim of this brief is to construct hyperbolic HNNs (HHNNs) as an analog of CHNNs. Hyperbolic algebra is a Clifford algebra based on Lorentzian geometry. In this brief, a hyperbolic neuron is defined in a manner analogous to a phasor neuron, which is a typical complex-valued neuron model. HHNNs share common concepts with CHNNs, such as the angle and energy. However, HHNNs and CHNNs are different in several aspects. The states of hyperbolic neurons do not form a circle, and, therefore, the start and end states are not identical. In the quantized version, unlike complex-valued neurons, hyperbolic neurons have an infinite number of states. PMID:24808287

Kobayashi, M

2013-02-01

425

Network acceleration techniques  

NASA Technical Reports Server (NTRS)

Splintered offloading techniques with receive batch processing are described for network acceleration. Such techniques offload specific functionality to a NIC while maintaining the bulk of the protocol processing in the host operating system ("OS"). The resulting protocol implementation allows the application to bypass the protocol processing of the received data. Such can be accomplished this by moving data from the NIC directly to the application through direct memory access ("DMA") and batch processing the receive headers in the host OS when the host OS is interrupted to perform other work. Batch processing receive headers allows the data path to be separated from the control path. Unlike operating system bypass, however, the operating system still fully manages the network resource and has relevant feedback about traffic and flows. Embodiments of the present disclosure can therefore address the challenges of networks with extreme bandwidth delay products (BWDP).

Crowley, Patricia (Inventor); Awrach, James Michael (Inventor); Maccabe, Arthur Barney (Inventor)

2012-01-01

426

Synchronization in complex networks  

SciTech Connect

Synchronization processes in populations of locally interacting elements are in the focus of intense research in physical, biological, chemical, technological and social systems. The many efforts devoted to understand synchronization phenomena in natural systems take now advantage of the recent theory of complex networks. In this review, we report the advances in the comprehension of synchronization phenomena when oscillating elements are constrained to interact in a complex network topology. We also overview the new emergent features coming out from the interplay between the structure and the function of the underlying pattern of connections. Extensive numerical work as well as analytical approaches to the problem are presented. Finally, we review several applications of synchronization in complex networks to different disciplines: biological systems and neuroscience, engineering and computer science, and economy and social sciences.

Arenas, A.; Diaz-Guilera, A.; Moreno, Y.; Zhou, C.; Kurths, J.

2007-12-12

427

LCOGT network observatory operations  

NASA Astrophysics Data System (ADS)

We describe the operational capabilities of the Las Cumbres Observatory Global Telescope Network. We summarize our hardware and software for maintaining and monitoring network health. We focus on methodologies to utilize the automated system to monitor availability of sites, instruments and telescopes, to monitor performance, permit automatic recovery, and provide automatic error reporting. The same jTCS control system is used on telescopes of apertures 0.4m, 0.8m, 1m and 2m, and for multiple instruments on each. We describe our network operational model, including workloads, and illustrate our current tools, and operational performance indicators, including telemetry and metrics reporting from on-site reductions. The system was conceived and designed to establish effective, reliable autonomous operations, with automatic monitoring and recovery - minimizing human intervention while maintaining quality. We illustrate how far we have been able to achieve that.

Pickles, Andrew; Hjelstrom, Annie; Boroson, Todd; Burleson, Ben; Conway, Patrick; De Vera, Jon; Elphick, Mark; Haworth, Brian; Rosing, Wayne; Saunders, Eric; Thomas, Doug; White, Gary; Willis, Mark; Walker, Zach

2014-08-01

428

Patient Safety Network  

NSDL National Science Digital Library

The Agency for Healthcare Research and Quality (AHRQ) Patient Safety Network (PSNet) website contains recent news and resources to provide those studying to be in the medical profession and for those currently in the medical field. Resources include an extensive glossary as well as a vast supply of articles from various periodicals. The site also contains numerous �Did You Know?� articles that include visual aids and citations. Articles can be sorted or browsed by target audience, resource type, clinical area, error type, safety target, approach to improving safety, and setting of care. Users have the ability to sign up for the weekly AHRQ Patient Safety Network and monthly AHRQ Web Morbidity and Mortality (WEBM&M) newsletters. Users may also sign up for a free account on the AHRQ Patient Safety Network website to receive e-mail alerts that match the users' interests.

429

The Social Network Classroom  

NASA Astrophysics Data System (ADS)

Online social networking is an important part in the everyday life of college students. Despite the increasing popularity of online social networking among students and faculty members, its educational benefits are largely untested. This paper presents our experience in using social networking applications and video content distribution websites as a complement of traditional classroom education. In particular, the solution has been based on effective adaptation, extension and integration of Facebook, Twitter, Blogger YouTube and iTunes services for delivering educational material to students on mobile platforms like iPods and 3 rd generation mobile phones. The goals of the proposed educational platform, described in this paper, are to make the learning experience more engaging, to encourage collaborative work and knowledge sharing among students, and to provide an interactive platform for the educators to reach students and deliver lecture material in a totally new way.

Bunus, Peter

430

Quantum random networks  

NASA Astrophysics Data System (ADS)

Quantum mechanics offers new possibilities to process and transmit information. In recent years, algorithms and cryptographic protocols exploiting the superposition principle and the existence of entangled states have been designed. They should allow us to realize communication and computational tasks that outperform any classical strategy. Here we show that quantum mechanics also provides fresh perspectives in the field of random networks. Already the simplest model of a classical random graph changes markedly when extended to the quantum case, where we obtain a distinct behaviour of the critical probabilities at which different subgraphs appear. In particular, in a network of N nodes, any quantum subgraph can be generated by local operations and classical communication if the entanglement between pairs of nodes scales as N-2. This result also opens up new vistas in the domain of quantum networks and their applications.

Perseguers, S.; Lewenstein, M.; Acín, A.; Cirac, J. I.

2010-07-01

431

The DARPA Quantum Network  

E-print Network

A team from BBN Technologies, Boston University, and Harvard University has recently built and begun to operate the world's first Quantum Key Distribution (QKD)network under DARPA sponsorship. The DARPA Quantum Network became fully operational on October 23, 2003 in BBN's laboratories, and in June 2004 was fielded through dark fiber under the streets of Cambridge, Mass., to link our campuses with non-stop quantum cryptography, twenty-four hours per day. As of December 2004, it consists of six nodes. Four are 5 MHz, BBN-built BB84 systems designed for telecommunications fiber and inter-connected by a photonic switch. Two are the electronics subsystems for a high speed free-space system designed and built by NIST. This paper describes the motivation for our work, the current status of the DARPA Quantum Network, its unique optical switching and key relay protocols, and our future plans.

Elliott, C

2004-01-01

432

The DARPA Quantum Network  

E-print Network

A team from BBN Technologies, Boston University, and Harvard University has recently built and begun to operate the world's first Quantum Key Distribution (QKD)network under DARPA sponsorship. The DARPA Quantum Network became fully operational on October 23, 2003 in BBN's laboratories, and in June 2004 was fielded through dark fiber under the streets of Cambridge, Mass., to link our campuses with non-stop quantum cryptography, twenty-four hours per day. As of December 2004, it consists of six nodes. Four are 5 MHz, BBN-built BB84 systems designed for telecommunications fiber and inter-connected by a photonic switch. Two are the electronics subsystems for a high speed free-space system designed and built by NIST. This paper describes the motivation for our work, the current status of the DARPA Quantum Network, its unique optical switching and key relay protocols, and our future plans.

Chip Elliott

2004-12-03

433

Network topology mapper  

DOEpatents

A method enables the topology of an acyclic fully propagated network to be discovered. A list of switches that comprise the network is formed and the MAC address cache for each one of the switches is determined. For each pair of switches, from the MAC address caches the remaining switches that see the pair of switches are located. For each pair of switches the remaining switches are determined that see one of the pair of switches on a first port and the second one of the pair of switches on a second port. A list of insiders is formed for every pair of switches. It is determined whether the insider for each pair of switches is a graph edge and adjacent ones of the graph edges are determined. A symmetric adjacency matrix is formed from the graph edges to represent the topology of the data link network.

Quist, Daniel A. (Los Alamos, NM); Gavrilov, Eugene M. (Los Alamos, NM); Fisk, Michael E. (Jemez, NM)

2008-01-15

434

Neural network technologies  

NASA Technical Reports Server (NTRS)

A whole new arena of computer technologies is now beginning to form. Still in its infancy, neural network technology is a biologically inspired methodology which draws on nature's own cognitive processes. The Software Technology Branch has provided a software tool, Neural Execution and Training System (NETS), to industry, government, and academia to facilitate and expedite the use of this technology. NETS is written in the C programming language and can be executed on a variety of machines. Once a network has been debugged, NETS can produce a C source code which implements the network. This code can then be incorporated into other software systems. Described here are various software projects currently under development with NETS and the anticipated future enhancements to NETS and the technology.

Villarreal, James A.

1991-01-01

435

High speed optical networks  

NASA Astrophysics Data System (ADS)

This overview will discuss core network technology and cost trade-offs inherent in choosing between "analog" architectures with high optical transparency, and ones heavily dependent on frequent "digital" signal regeneration. The exact balance will be related to the specific technology choices in each area outlined above, as well as the network needs such as node geographic spread, physical connectivity patterns, and demand loading. Over the course of a decade, optical networks have evolved from simple single-channel SONET regenerator-based links to multi-span multi-channel optically amplified ultra-long haul systems, fueled by high demand for bandwidth at reduced cost. In general, the cost of a well-designed high capacity system is dominated by the number of optical to electrical (OE) and electrical to optical (EO) conversions required. As the reach and channel capacity of the transport systems continued to increase, it became necessary to improve the granularity of the demand connections by introducing (optical add/drop multiplexers) OADMs. Thus, if a node requires only small demand connectivity, most of the optical channels are expressed through without regeneration (OEO). The network costs are correspondingly reduced, partially balanced by the increased cost of the OADM nodes. Lately, the industry has been aggressively pursuing a natural extension of this philosophy towards all-optical "analog" core networks, with each demand touching electrical digital circuitry only at the in/egress nodes. This is expected to produce a substantial elimination of OEO costs, increase in network capacity, and a notionally simpler operation and service turn-up. At the same time, such optical "analog" network requires a large amount of complicated hardware and software for monitoring and manipulating high bit rate optical signals. New and more complex modulation formats that provide resiliency to both optical noise and nonlinear propagation effects are important for extended unregenerated reach. More sophisticated optical amplifiers provide lower noise for increased reach and increased spectral bandwidth for higher wavelength count lower wavelength blocking probability. Optical analog networks also require methods for mitigating optical power transients, for controlling optical spectral flatness, and for dynamically managing changes (e.g. in chromatic dispersion and polarization mode dispersion.) Since signals stay in the optical domain, optical performance monitoring techniques are required for fault isolation and correction. Efficient routing of optical signals also requires sophisticated switching nodes with an ability to selectively steer optical signals into several directions with single-channel spectral granularity. Most of these technologies are not modular and require interruption of service if not deployed at the initial system installation, thereby increasing first install costs substantially, even if initial capacity loading is small. Further, validation of systems and software targeting a specific network design is complex. Only a small fraction of the total network may be reasonably reproduced in the lab, and many field configurations are not predictable or even dynamic. Thus, extra system margin has to be allocated to handle the behavior uncertainty. To constrain the complexity of both hardware technology and software algorithms, regions of network transparency can be established with OEO forced at perimeters. Thus, "analog" regions are surrounded by "digital" interfaces. Following are some example tradeoffs that will be discussed. What is a good modulation format choice, and does increased reach and impairment resiliency justify hardware and controls that are more complicated? What are reasonable amplifier choices to make under specific network assumptions? Can high transport system capacity be leveraged to simplify optical switch node design by reducing spectral efficiency?

Frankel, Michael Y.; Livas, Jeff

2005-02-01

436

Prostate Cancer Regulatory Networks  

PubMed Central

Although the timing with which common epithelial malignancies arise and become established remains a matter of debate, it is clear that by the time they are detected these tumors harbor hundreds of deregulated, aberrantly expressed or mutated genes. This enormous complexity poses formidable challenges to identify gene pathways that are drivers of tumorigenesis, potentially suitable for therapeutic intervention. An alternative approach is to consider cancer pathways as interconnected networks, and search for potential nodal proteins capable of connecting multiple signaling networks of tumor maintenance. We have modeled this approach in advanced prostate cancer, a condition with current limited therapeutic options. We propose that the integration of three signaling networks, including chaperone-mediated mitochondrial homeostasis, integrin-dependent cell signaling, and Runx2-regulated gene expression in the metastatic bone microenvironment plays a critical role in prostate cancer maintenance, and offers novel options for molecular therapy. PMID:19492418

Altieri, Dario C.; Languino, Lucia R.; Lian, Jane B.; Stein, Janet L.; Leav, Irwin; van Wijnen, Andre J.; Jiang, Zhong; Stein, Gary S.

2010-01-01

437

Community Seismic Network (CSN)  

NASA Astrophysics Data System (ADS)

The CSN is a network of low-cost accelerometers deployed in the Pasadena, CA region. It is a prototype network with the goal of demonstrating the importance of dense measurements in determining the rapid lateral variations in ground motion due to earthquakes. The main product of the CSN is a map of peak ground produced within seconds of significant local earthquakes that can be used as a proxy for damage. Examples of this are shown using data from a temporary network in Long Beach, CA. Dense measurements in buildings are also being used to determine the state of health of structures. In addition to fixed sensors, portable sensors such as smart phones are also used in the network. The CSN has necessitated several changes in the standard design of a seismic network. The first is that the data collection and processing is done in the "cloud" (Google cloud in this case) for robustness and the ability to handle large impulsive loads (earthquakes). Second, the database is highly de-normalized (i.e. station locations are part of waveform and event-detection meta data) because of the mobile nature of the sensors. Third, since the sensors are hosted and/or owned by individuals, the privacy of the data is very important. The location of fixed sensors is displayed on maps as sensor counts in block-wide cells, and mobile sensors are shown in a similar way, with the additional requirement to inhibit tracking that at least two must be present in a particular cell before any are shown. The raw waveform data are only released to users outside of the network after a felt earthquake.

Clayton, R. W.; Heaton, T. H.; Kohler, M. D.; Cheng, M.; Guy, R.; Chandy, M.; Krause, A.; Bunn, J.; Olson, M.; Faulkner, M.

2011-12-01

438

Bornholm network analysis rup Nielsen  

E-print Network

Bornholm network analysis Finn A Ã? rup Nielsen Informatics and Mathematical Modelling Technical A Ã? rup Nielsen, IMM, DTU April 7, 2002 OVERVIEW #15; Applications. #15; The network as a matrix #15; Centrality #15; Iterative centrality #15; Network measures #15; Max ow-min cut 2 #12; Finn A Ã? rup Nielsen

Nielsen, Finn Ã?rup

439

Spatial queries in sensor networks  

Microsoft Academic Search

Recent advances in low-power sensing devices coupled with the widespread availability of wireless ad-hoc networks have fueled the development of sensor networks. These are typically deployed over wide areas to gather data in the environment and monitor events of interest. The ability to run spatial queries is extremely useful for sensor networks. Spatial query execution has been extensively studied in

Amir Soheili; Vana Kalogeraki; Dimitrios Gunopulos

2005-01-01

440

Microscopic evolution of social networks  

Microsoft Academic Search

We present a detailed study of network evolution by analyzing four large online social networks with full temporal information about node and edge arrivals. For the first time at such a large scale, we study individual node arrival and edge creation processes that collectively lead to macroscopic properties of networks. Using a methodology based on the maximum-likelihood principle, we in-

Jure Leskovec; Lars Backstrom; Ravi Kumar; Andrew Tomkins

2008-01-01

441

Computer Networking Goes to School.  

ERIC Educational Resources Information Center

Describes the design and implementation of the microcomputer network that will soon link every vocational center and comprehensive high school in West Virginia. The author discusses the advantages of networking, what equipment is used, instructional emphases, how various programs use the network, teacher training, and learner outcomes. (CT)

Cook, John

1985-01-01

442

Airborne information and reconnaissance network  

Microsoft Academic Search

We describe a broadband\\/tactical communication network architecture for implementing a rapidly deployable, broadband, mobile, wireless network using unmanned airborne relay vehicles for extended LOS range. The essential concept consists of a deployed group of unmanned airborne vehicles (UAV) providing wireless network service among mobile terrestrial and airborne stations. Each UAV is linked via wireless to one or more of its

Arun Ayyagari; J. P. Harrang; S. Ray

1996-01-01

443

Inference networks for document retrieval  

Microsoft Academic Search

Abstract The use of inference networks,to support,document,retrieval is introduced.,A network-basead retrieval model,is described and compared,to conventional,probabilis- tic and Boolean models. 1,Introduction Network,representations,have,been,used,in information,retrieval since at least the early

H. Turtle; W. B. Croft

1989-01-01

444

Network-Based Management Procedures.  

ERIC Educational Resources Information Center

Network-based management procedures serve as valuable aids in organizational management, achievement of objectives, problem solving, and decisionmaking. Network techniques especially applicable to educational management systems are the program evaluation and review technique (PERT) and the critical path method (CPM). Other network charting…

Buckner, Allen L.

445

NLD SENSOR NETWORKS: THEORETICAL STUDIES  

E-print Network

1 NLD SENSOR NETWORKS: THEORETICAL STUDIES Theory Faculty: Prof. Thomas Antonsen (ECE, Physics Briefly Discusses Three Current Research Projects · Adaptive Learning Network Sensor Using Chaos Sync model to simulate coupled systems of several chaotic oscillators acting in a sensor network. ·Talk

Anlage, Steven

446

Distributed Algorithms for Sensor Networks  

E-print Network

Distributed Algorithms for Sensor Networks By Christoph Lenzen1 and Roger Wattenhofer2 1 School, Switzerland Distributed algorithms are an established tool for designing protocols for sensor networks. In this article we discuss the relation between distributed computing theory and sensor network applications

447

Scalable Coordination in Sensor Networks  

Microsoft Academic Search

Network sensorsthose that coordinate amongst themselvesto achieve a larger sensing taskwill revolutionizeinformation gathering and processing both in urban environmentsand in inhospitable terrain. The sheer numbers ofthese sensors and the expected dynamics in these environmentspresent unique challenges in the design of unattendedautonomous sensor networks. These challenges lead us tohypothesize that sensor network coordination applicationsmay need to be structured dierently from...

Deborah Estrin; John Heidemann; Ramesh Govindan

1999-01-01

448

NASA Integrated Space Communications Network  

NASA Technical Reports Server (NTRS)

The NASA Integrated Network for Space Communications and Navigation (SCaN) has been in the definition phase since 2010. It is intended to integrate NASA s three existing network elements, i.e., the Space Network, Near Earth Network, and Deep Space Network, into a single network. In addition to the technical merits, the primary purpose of the Integrated Network is to achieve a level of operating cost efficiency significantly higher than it is today. Salient features of the Integrated Network include (a) a central system element that performs service management functions and user mission interfaces for service requests; (b) a set of common service execution equipment deployed at the all stations that provides return, forward, and radiometric data processing and delivery capabilities; (c) the network monitor and control operations for the entire integrated network are conducted remotely and centrally at a prime-shift site and rotating among three sites globally (a follow-the-sun approach); (d) the common network monitor and control software deployed at all three network elements that supports the follow-the-sun operations.

Tai, Wallace; Wright, Nate; Prior, Mike; Bhasin, Kul

2012-01-01

449

Neural Networks for Readability Analysis.  

ERIC Educational Resources Information Center

This paper describes and reports on the performance of six related artificial neural networks that have been developed for the purpose of readability analysis. Two networks employ counts of linguistic variables that simulate a traditional regression-based approach to readability. The remaining networks determine readability from "visual snapshots"…

McEneaney, John E.

450

Systems Competition and Network Effects  

Microsoft Academic Search

This paper discusses firm behavior, market performance, and the public and private institutions that arise in systems markets, i.e., markets where consumers use compatible components together to generate benefits. In such markets, which include communications networks and 'hardware\\/software' networks, popular products are inherently more valuable. These 'network effects' can drive corporate strategies and are critical in understanding innovation in many

Michael L Katz; Carl Shapiro

1994-01-01

451

Hypothesis Generation in Signaling Networks  

Microsoft Academic Search

Biological signaling networks comprise the chemical processes by which cells detect and re- spond to changes in their environment. Such networks have been implicated in the regulation of important cellular activities, including cellular reproduction, mobility, and death. Though technological and scientific advances have facilitated the rapid accumulation of information about signaling networks, utilizing these massive information resources has become infeasible

Derek A. Ruths; Luay Nakhleh; M. Sriram Iyengar; Shrikanth A. G. Reddy; Prahlad T. Ram

2006-01-01

452

Architecture selection for neural networks  

Microsoft Academic Search

Researchers worldwide converge into the fact that the exhaustive search over the space of network architectures is computationally infeasible even for networks of modest size. The use of heuristic strategies that dramatically reduce the search complexity is a common technique. These heuristic approaches employ directed search algorithms, such as selection of the number of nodes via sequential network construction (SNC),

Pythagoras Karampiperis; Nikos Manouselis; Theodore B. Trafalis

2002-01-01

453

A survey on sensor networks  

Microsoft Academic Search

The advancement in wireless communications and electronics has enabled the development of low-cost sensor networks. The sensor networks can be used for various application areas (e.g., health, military, home). For different application areas, there are different technical issues that researchers are currently resolving. The current state of the art of sensor networks is captured in this article, where solutions are

Ian F. Akyildiz; Weilian Su; Yogesh Sankarasubramaniam; Erdal Cayirci

2002-01-01

454

VEHICLE NETWORKS: ACHIEVING REGULAR FORMATION  

E-print Network

VEHICLE NETWORKS: ACHIEVING REGULAR FORMATION MADALENA CHAVES, ROBERT DAY, LUCIA GOMEZ a network of vehicles exchanging information among themselves with the intention of achieving a specified the performance of the vehicle network. A stochastic model for information flow is also considered, allowing

455

The Johns Hopkins Hospital Network  

PubMed Central

The Johns Hopkins Hospital has initiated an ambitious program to apply modern technologies to the development of a new, comprehensive clinical information system. One component of this system is a networking technology for supporting the integration of diverse and functionally distinct information systems. This paper discusses the selection of the networking technology implemented at JHH, issues and problems, networking concepts, protocols and reliability.

Tolchin, Stephen G.; Barta, Wendy; Harkness, Kenneth

1985-01-01

456

Presented by NCCS Network Roadmap  

E-print Network

optimized data transfer nodes ­ Deployed network and infrastructure to support CMRS · 2011 ­ Evaluate IB/Ethernet Summary: Continuous improvement projects in both high-speed wide-area connectivity and ultra-high-speed_Networking_SC10 NCCS network roadmap summary Ethernet core scaled to match wide-area connectivity and archive

457

Neural network learning without backpropagation.  

PubMed

The method introduced in this paper allows for training arbitrarily connected neural networks, therefore, more powerful neural network architectures with connections across layers can be efficiently trained. The proposed method also simplifies neural network training, by using the forward-only computation instead of the traditionally used forward and backward computation. PMID:20858577

Wilamowski, Bogdan M; Yu, Hao

2010-11-01

458

Cooperation in wireless communication networks  

Microsoft Academic Search

The concept of cooperation in wireless communication networks has drawn significant attention recently from both academia and industry as it can be effective in addressing the performance limitations of wireless networks due to user mobility and the scarcity of network resources. In this article, we aim to shed some light on potential benefits of such an approach and discuss its

Weihua Zhuang; Muhammad Ismail

2012-01-01

459

Bayesian Networks Applications in Genetics  

E-print Network

Bayesian Networks Applications in Genetics Segregation, IBD and Linkage from the Perspective the Perspective of BNT #12;Bayesian Networks Applications in Genetics Outline 1 Bayesian Networks Model and Notations Belief Propagation Exact Inference 2 Applications in Genetics Segregation IBD Linkage G. NUEL

Nuel, Gregory

460

Fast restoration of ATM networks  

Microsoft Academic Search

Asynchronous transfer mode (ATM) is now well recognized as the fundamental switching and multiplexing technique for future broadband ISDN. As these networks will be increasingly relied upon for providing a multitude of integrated voice, data, and video services, network reliability is a key concern. There are several intrinsic features of ATM networks that could potentially be exploited to provide improved

Jon Anderson; B. T. Doshi; Subrahmanyam Dravida; P. Harshavardhana

1994-01-01

461

Flow networks for Ocean currents  

NASA Astrophysics Data System (ADS)

Complex networks have been successfully applied to various systems such as society, technology, and recently climate. Links in a climate network are defined between two geographical locations if the correlation between the time series of some climate variable is higher than a threshold. Therefore, network links are considered to imply heat exchange. However, the relationship between the oceanic and atmospheric flows and the climate network's structure is still unclear. Recently, a theoretical approach verifying the correlation between ocean currents and surface air temperature networks has been introduced, where the Pearson correlation networks were constructed from advection-diffusion dynamics on an underlying flow. Since the continuous approach has its limitations, i.e., by its high computational complexity, we here introduce a new, discrete construction of flow-networks, which is then applied to static and dynamic velocity fields. Analyzing the flow-networks of prototypical flows we find that our approach can highlight the zones of high velocity by degree and transition zones by betweenness, while the combination of these network measures can uncover how the flow propagates within time. We also apply the method to time series data of the Equatorial Pacific Ocean Current and the Gulf Stream ocean current for the changing velocity fields, which could not been done before, and analyse the properties of the dynamical system. Flow-networks can be powerful tools to theoretically understand the step from system's dynamics to network's topology that can be analyzed using network measures and is used for shading light on different climatic phenomena.

Tupikina, Liubov; Molkenthin, Nora; Marwan, Norbert; Kurths, Jürgen

2014-05-01

462

Teachers Seek Specialized Peer Networks  

ERIC Educational Resources Information Center

Within the wide expanse of social networking, educators appear to be gravitating to more protected and exclusive spaces. While teachers often use such popular mainstream social networks as Facebook, they are more likely to seek out and return to less-established networks that offer the privacy, peer-to-peer connections, and resource sharing that…

Tomassini, Jason

2013-01-01

463

Reducing Distortion in Phylogenetic Networks  

Microsoft Academic Search

When multiple genes are used in a phylogenetic study, the result is often a collection of incompatible trees. Phylogenetic networks and super-networks can be employed to analyze and visualize the incom- patible signals in such a data set. In many situations, it is important to have control over the amount of imcompatibility that is represented in a phylogenetic network, for

Daniel H. Huson; Mike A. Steel; Jim Whitfield

2006-01-01

464

Frenetic: A Network Programming Language  

Microsoft Academic Search

Modern networks provide a variety of interrelated services including routing, traffic monitoring, load balancing, and access control. Unfortunately, the languages used to program today's networks lack modern features - they are usually defined at the low level of abstraction supplied by the underlying hardware and they fail to provide even rudimentary support for modular programming. As a result, network programs

Nate Foster; Rob Harrison; Michael J. Freedman; Christopher Monsanto; Jennifer Rexford; Alec Story; David Walker

2011-01-01

465

Network Systems Administration Needs Assessment.  

ERIC Educational Resources Information Center

In spring 1996, Lexington Community College (LCC) in Kentucky, conducted a survey to gather information on employment trends and educational needs in the field of network systems administration (NSA). NSA duties involve the installation and administration of network operating systems, applications software, and networking infrastructure;…

Lexington Community Coll., KY. Office of Institutional Research.

466

Benchmarking a network storage service  

Microsoft Academic Search

Benchmarking a network file server introduces some unique considerations over traditional benchmarking scenarios. Since the user is executing on a client system interconnected to the file server, the client and network must be provided for during benchmarking. During a recent procurement action, Sandia National Laboratories (SNL) was challenged to develop a benchmark suite that would accurately test the network requirements.

Suzanne M. Kelly; Rena A. Haynes; M. J. Ernest

1991-01-01

467

Process-in-Network: A Comprehensive Network Processing Approach  

PubMed Central

A solid and versatile communications platform is very important in modern Ambient Intelligence (AmI) applications, which usually require the transmission of large amounts of multimedia information over a highly heterogeneous network. This article focuses on the concept of Process-in-Network (PIN), which is defined as the possibility that the network processes information as it is being transmitted, and introduces a more comprehensive approach than current network processing technologies. PIN can take advantage of waiting times in queues of routers, idle processing capacity in intermediate nodes, and the information that passes through the network. PMID:22969390

Urzaiz, Gabriel; Villa, David; Villanueva, Felix; Lopez, Juan Carlos

2012-01-01

468

Synthetic biological networks  

NASA Astrophysics Data System (ADS)

Despite their obvious relationship and overlap, the field of physics is blessed with many insightful laws, while such laws are sadly absent in biology. Here we aim to discuss how the rise of a more recent field known as synthetic biology may allow us to more directly test hypotheses regarding the possible design principles of natural biological networks and systems. In particular, this review focuses on synthetic gene regulatory networks engineered to perform specific functions or exhibit particular dynamic behaviors. Advances in synthetic biology may set the stage to uncover the relationship of potential biological principles to those developed in physics.

Archer, Eric; Süel, Gürol M.

2013-09-01

469

Global Telescope Network Website  

NSDL National Science Digital Library

The Global Telescope Network (GTN) is an informal association of scientists, students, individuals and observatories interested in supporting the NASA Fermi Gamma-ray Space Telescope (formerly GLAST), Swift, and XMM-Newton missions by obtaining and reducing ground-based observations for objects related to the primary science goals for these missions. The GTN website involves students, teachers, and amateur astronomers in cutting-edge astronomical research; contains activities and instructional materials for a range of levels and interests; and provides mentoring in research practices, telescope use, data analysis and educational resources for both partners (those with their own telescopes) and associates (those who wish to use a network telescope).

2012-12-06

470

Teacher Leaders Network  

NSDL National Science Digital Library

The Teacher Leaders Network (TLN) is an independent, web-based network of experienced, leading, and award-winning teachers who have achieved success as authors, professional developers, trained mentors, policy consultants, and community leaders. This virtual community participates in daily online discussions that explore and debate the merits of educational policies, techniques, and philosophies. Materials available at the TLN web site include weblogs in which members share their experience and insights; links to resources for teacher leadership, coaching and mentoring, education policy, and other topics; links to news articles and publications; and information on the organization's sponsors, funding, and partners.

471

Interpreting network formalisms  

SciTech Connect

In a recent paper, Reiter and Criscuolo (1980) remark that (semantic) networks are notational variants of logical formulae is by now a truism in artificial intelligence circles. Shamelessly exploiting the foregoing quote as a pretext, the author attempts to sketch adequate semantic accounts for at least two (kinds of) semantic network formalisms: one, based on the notion of inheritance, one, not. A crucial condition of adequacy to be satisfied is fidelity to some of the intuitions of the creators of the formalisms. 34 references.

Israel, D.J.

1983-01-01

472

Analysis of network statistics  

NASA Astrophysics Data System (ADS)

This talk discusses the types and sources of data obtainable from networks of computer systems and terminals connected by communications paths. These paths often utilize mixtures of protocols and devices (such as modems, multiplexors, switches and front-ends) from multiple vendors. The talk describes how the data can be gathered from these devices and protocol layers, consolidated, stored, and analyzed. The analysis typically includes merging information from data bases describing the network topology, components, etc. Examples of reports and displays of the information gleaned are shown, together with illustrations of how the information may be useful for troubleshooting, performance measurement, auditing, accounting, and trend prediction.

Cottrell, R. L. A.

1987-08-01

473

River Network Online  

NSDL National Science Digital Library

The mission of River Network, a non-governmental organization, is "to help people organize to protect and restore rivers and watersheds." To that end, the River Network homepage offers a wealth of information and links on rivers and watersheds including publications, upcoming conferences, watershed protection issues, river conservation job listings, related organizations, and a searchable National Directory of River and Watershed Organizations. The What's New section announces recent publications, events, and ongoing important river/watershed issues. For anyone interested in learning about or participating in River/Watershed initiatives, this is an excellent resource.

1999-01-01

474

Social networking and adolescents.  

PubMed

Online social networking is a 21st century innovation increasingly embraced by today's young people. It provides new opportunities for communication that expand an adolescent's world. Yet adults, often suspicious of new trends and technologies initially embraced by youth, often see these new environments as perilous places to visit. These fears have been accentuated by media hype, especially about sexual predators. How dangerous are they? Because the rush to go on these sites is a new phenomenon, research is as yet scant. This review explores current beliefs and knowledge about the dangers of social networking sites. PMID:19492691

Fuld, Gilbert L

2009-04-01

475

Network and Computer Security  

NSDL National Science Digital Library

A wide variety of educational resources and course materials are available through the Massachusetts Institute of Technologyâ??s Open Courseware Project. This particular course â??Network and Computer Securityâ? contains problem sets and exams with solutions as well as a full reading list that is accessible to the public. Some of the topics covered in this course are: cryptography, authentication and identification schemes, viruses, software protection, firewalls, and electronic commerce among others. Computer science students will find the reading materials and practice problems available here especially useful. This is an excellent source of information for anyone who is currently studying or interested in network and computer security.

Rivest, Ronald L.

476

Hybrid network intrusion detection  

NASA Astrophysics Data System (ADS)

We report on a machine learning classifier that can be used to discover the patterns hidden within large networking data flows. It utilizes an existing intrusion detection system (IDS) as an oracle to learn a faster, less resource intensive normalcy classifier as a front-end to a hybrid network IDS. This system has the capability to recognize new attacks that are similar to known attack signatures. It is also more highly scalable and distributable than the signature-based IDS. The new hybrid design also allows distributed updates and retraining of the normalcy classifier to stay up-to-date with current threats.

Tahmoush, David

2014-05-01

477

E-Print Network  

NSDL National Science Digital Library

Created by the United States Department of Energy, this website allows users to explore online papers that have been submitted for distribution and review among peers; for publication in journals; or for presentations at conferences. Through the E-print Network, advanced students and scientists can search e-prints on many websites and databases, browse e-prints by subject, and find many scientific societies. Although the network primarily contains physics-related documents, e-prints dealing with other subjects such as chemistry, material sciences, and nuclear sciences are also included.

478

Adaptive parallel logic networks  

NASA Technical Reports Server (NTRS)

Adaptive, self-organizing concurrent systems (ASOCS) that combine self-organization with massive parallelism for such applications as adaptive logic devices, robotics, process control, and system malfunction management, are presently discussed. In ASOCS, an adaptive network composed of many simple computing elements operating in combinational and asynchronous fashion is used and problems are specified by presenting if-then rules to the system in the form of Boolean conjunctions. During data processing, which is a different operational phase from adaptation, the network acts as a parallel hardware circuit.

Martinez, Tony R.; Vidal, Jacques J.

1988-01-01

479

Elasticity of biopolymer networks  

NASA Astrophysics Data System (ADS)

This thesis presents a study of the elasticity of three very different cytoskeletal materials, microtubules (MTs), filamentous actin (F-actin) and vimentin, one of the intermediate filaments (IFs). Using bulk rheology, multiple particle tracking, confocal microscopy, and transmission electron microscopy (TEM), we study the microscopic origin of the elasticity of these cytoskeletal networks. In Chapter 1, we briefly introduce the properties of the three components of cytoskeletal filaments as well as the rheology essential to provide the background and motivation of this thesis. In Chapter 2, we describe the materials and experimental techniques involved. In Chapter 3, we study solutions of purified MTs, as well as networks permanently cross-linked with biotin-NeutrAvidin. We show that the mechanical properties of MT solutions cannot be explained by the non-interacting rigid rod model. Instead, they show behavior very similar to the permanently cross-linked networks, suggesting the presence of effective cross-linking even in pure MT solutions. We develop a simple model based on transient cross-linking interactions between MTs to interpret the rheological response. We also calculate a lower bound estimate of the strength of this interaction. In Chapter 4, we investigate the mechanical response of the composite networks of F-actin and MTs. We find that even a small concentration of MTs leads to dramatic and qualitative changes in the elastic properties of F-actin networks. MTs provide a way to regulate the nonlinear stiffening response of F-actin. Theoretically this can be understood in terms of an inhomogeneity in the strain field of the gel. This finding is highly relevant for interpretation of the mechanical behavior of the intracellular cytoskeleton, in which a dilute network of MTs coexists with a denser meshwork of more flexible biopolymers such as F-actin. In Chapter 5, we study the third and final filamentous protein of the cytoskeleton, intermediate filaments (IFs). We find that divalent ions act as cross-linkers in vimentin networks. We demonstrate that the linear and nonlinear elastic responses of vimentin IF networks at intermediate stress can be quantitatively explained by stretching the entropic fluctuations of single semiflexible filaments; at high stress, we propose that enthalpic stretching of the individual filaments contributes to the observed nonlinear response.

Lin, Yi-Chia

2009-12-01

480

Network line plotting  

E-print Network

from one zone to another are placed on the links of the minimum path tree between ti. e zones, regardless of the volume capacity of the links. Upon analyzing the points of stress of the future loading of the network, proposals for changes..." to the system. Traffic Network Model Establishing a netvrork description by coding data for key-punch- ing into link data cards is the first job of the traffic analyst. The following explanation will enable development of the sample street system shown...

Pry, William Freeman

2012-06-07

481

Evaluating predictive performance of network biomarkers with network structures.  

PubMed

Network is a powerful structure which reveals valuable characteristics of the underlying data. However, previous work on evaluating the predictive performance of network-based biomarkers does not take nodal connectedness into account. We argue that it is necessary to maximize the benefit from the network structure by employing appropriate techniques. To address this, we aim to learn a weight coefficient for each node in the network from the quantitative measure such as gene expression data. The weight coefficients are computed from an optimization problem which minimizes the total weighted difference between nodes in a network structure; this can be expressed in terms of graph Laplacian. After obtaining the coefficient vector for the network markers, we can then compute the corresponding network predictor. We demonstrate the effectiveness of the proposed method by conducting experiments using published breast cancer biomarkers with three patient cohorts. Network markers are first grouped based on GO terms related to cancer hallmarks. We compare the predictive performance of each network marker group across gene expression datasets. We also evaluate the network predictor against the average method for feature aggregation. The reported results show that the predictive performance of network markers is generally not consistent across patient cohorts. PMID:25219385

Gao, Shang; Karakira, Ibrahim; Afra, Salim; Naji, Ghada; Alhajj, Reda; Zeng, Jia; Demetrick, Douglas

2014-10-01

482

Inferring network interactions using recurrent neural networks and swarm intelligence.  

PubMed

We present a novel algorithm combining artificial neural networks and swarm intelligence (SI) methods to infer network interactions. The algorithm uses ant colony optimization (ACO) to identify the optimal architecture of a recurrent neural network (RNN), while the weights of the RNN are optimized using particle swarm optimization (PSO). Our goal is to construct an RNN that mimics the true structure of an unknown network and the time-series data that the network generated. We applied the proposed hybrid SI-RNN algorithm to infer a simulated genetic network. The results indicate that the algorithm has a promising potential to infer complex interactions such as gene regulatory networks from time-series gene expression data. PMID:17946231

Ressom, Habtom W; Zhang, Yuji; Xuan, Jianhua; Wang, Yue; Clarke, Robert

2006-01-01

483

Network robustness of multiplex networks with interlayer degree correlations  

NASA Astrophysics Data System (ADS)

We study the robustness properties of multiplex networks consisting of multiple layers of distinct types of links, focusing on the role of correlations between degrees of a node in different layers. We use generating function formalism to address various notions of the network robustness relevant to multiplex networks, such as the resilience of ordinary and mutual connectivity under random or targeted node removals, as well as the biconnectivity. We found that correlated coupling can affect the structural robustness of multiplex networks in diverse fashion. For example, for maximally correlated duplex networks, all pairs of nodes in the giant component are connected via at least two independent paths and network structure is highly resilient to random failure. In contrast, anticorrelated duplex networks are on one hand robust against targeted attack on high-degree nodes, but on the other hand they can be vulnerable to random failure.

Min, Byungjoon; Yi, Su Do; Lee, Kyu-Min; Goh, K.-I.

2014-04-01

484

Whether information network supplements friendship network  

NASA Astrophysics Data System (ADS)

Homophily is a significant mechanism for link prediction in complex network, of which principle describes that people with similar profiles or experiences tend to tie with each other. In a multi-relationship network, friendship among people has been utilized to reinforce similarity of taste for recommendation system whose basic idea is similar to homophily, yet how the taste inversely affects friendship prediction is little discussed. This paper contributes to address the issue by analyzing two benchmark data sets both including user's behavioral information of taste and friendship based on the principle of homophily. It can be found that the creation of friendship tightly associates with personal taste. Especially, the behavioral information of taste involving with popular objects is much more effective to improve the performance of friendship prediction. However, this result seems to be contradictory to the finding in Zhang et al. (2013) that the behavior information of taste involving with popular objects is redundant in recommendation system. We thus discuss this inconformity to comprehensively understand the correlation between them.

Miao, Lili; Zhang, Qian-Ming; Nie, Da-Cheng; Cai, Shi-Min

2015-02-01

485

Evolution of cosmic string networks  

NASA Technical Reports Server (NTRS)

A discussion of the evolution and observable consequences of a network of cosmic strings is given. A simple model for the evolution of the string network is presented, and related to the statistical mechanics of string networks. The model predicts the long string density throughout the history of the universe from a single parameter, which researchers calculate in radiation era simulations. The statistical mechanics arguments indicate a particular thermal form for the spectrum of loops chopped off the network. Detailed numerical simulations of string networks in expanding backgrounds are performed to test the model. Consequences for large scale structure, the microwave and gravity wave backgrounds, nucleosynthesis and gravitational lensing are calculated.

Albrecht, Andreas; Turok, Neil

1989-01-01

486

Mixed deterministic and probabilistic networks  

PubMed Central

The paper introduces mixed networks, a new graphical model framework for expressing and reasoning with probabilistic and deterministic information. The motivation to develop mixed networks stems from the desire to fully exploit the deterministic information (constraints) that is often present in graphical models. Several concepts and algorithms specific to belief networks and constraint networks are combined, achieving computational efficiency, semantic coherence and user-interface convenience. We define the semantics and graphical representation of mixed networks, and discuss the two main types of algorithms for processing them: inference-based and search-based. A preliminary experimental evaluation shows the benefits of the new model. PMID:20981243

Dechter, Rina

2010-01-01

487

Computers, Networks and Education.  

ERIC Educational Resources Information Center

Discussed is how globally networked, easy-to-use computers can enhance learning only within an educational environment that encourages students to question "facts" and seek challenges. The strengths and weaknesses of computers used as amplifiers for learning are described. (KR)

Kay, Alan C.

1991-01-01

488

Research Network Product Development  

E-print Network

/institution are focusing on a broad variety of themes ranging from storage technology to electrical drive, from vehicle safety to future integration of electric mobility in urban transport systems. The network constitutes.-Ing Dietmar Göhlich Dipl.-Ing Felix Spangenberg 5 E Bus Berlin e-THF e-logistics car sharing multimodal

Berlin,Technische Universität

489

Social Networks and Entrepreneurship  

Microsoft Academic Search

A central tenet in sociology holds that positions in social structure influence the attitudes, behaviors, and outcomes of the actors occupying those positions. Though this proposition underlies much sociological thinking, perhaps the clearest instantiation of it appears in the literature collectively referred to as 'social network theory'. Research in this area investigates both the structure of the relations between social

Arent Greve; Janet W. Salaff

2003-01-01

490

The Falcon Telescope Network  

NASA Astrophysics Data System (ADS)

The Falcon Telescope Network (FTN) is a global network of small aperture telescopes developed by the Center for Space Situational Awareness Research in the Department of Physics at the United States Air Force Academy (USAFA). Consisting of commercially available equipment, the FTN is a collaborative effort between USAFA and other educational institutions ranging from two- and four-year colleges to major research universities. USAFA provides the equipment (e.g. telescope, mount, camera, filter wheel, dome, weather station, computers and storage devices) while the educational partners provide the building and infrastructure to support an observatory. The user base includes USAFA along with K-12 and higher education faculty and students. Since the FTN has a general use purpose, objects of interest include satellites, astronomical research, and STEM support images. The raw imagery, all in the public domain, will be accessible to FTN partners and will be archived at USAFA in the Cadet Space Operations Center. FTN users will be able to submit observational requests via a web interface. The requests will then be prioritized based on the type of user, the object of interest, and a user-defined priority. A network wide schedule will be developed every 24 hours and each FTN site will autonomously execute its portion of the schedule. After an observational request is completed, the FTN user will receive notification of collection and a link to the data. The Falcon Telescope Network is an ambitious endeavor, but demonstrates the cooperation that can be achieved by multiple educational institutions.

Chun, F.; Tippets, R.; Dearborn, M.; Gresham, K.; Freckleton, R.; Douglas, M.

2014-09-01

491

Chinese VLBI Network Project  

NASA Astrophysics Data System (ADS)

The Chinese VLBI Network (CVN) project was proposed early in 1979, and since then VLBI research has been actively developed in Shanghai Observatory. However, only recently the whole project was accepted by the Astronomy Committee, Division of Mathematics and Physics, Academia Sinica.

Wan, T. S.; Qian, Z.

492

Great Lakes Information Network  

NSDL National Science Digital Library

The Great Lakes Information Network (GLIN) is a partnership that has compiled information relating to the binational Great Lakes-St. Lawrence region of North America. Sections of the site include an overview of the Great Lakes, the environment of the Great Lakes, the economy of the Great Lakes, education, maps and Geographic Information Systems (GIS), and tourism.

2007-10-26

493

Computers: Networks, Registration  

ERIC Educational Resources Information Center

A computer network serves 53 schools and colleges in North Carolina; Essex County College in New Jersey has an on-line computer registration system that is used by students and administrators to enter information or ask questions. (Author/MLF)

Nation's Schools and Colleges, 1975

1975-01-01

494

STREAM NETWORK TEMPERATURE  

EPA Science Inventory

The Stream Network Temperature (SNTEMP) model is a mechanistic, one-dimensional heat transport formulation that predicts daily mean and maximum water temperature as a function of stream distance and environmental heat flux. Net heat flux is calculated as the sum of heat to or fr...

495

Architecting the Network  

ERIC Educational Resources Information Center

The word "architect" calls to mind a designer of buildings. An architect's job is to develop a structure to fit the client's needs, some of which are conflicting (or seem to be). When it comes to designing a campus network, IT infrastructure architects have a similar function. Like a building architect, an IT architect must develop a…

Chretien, Wendy

2007-01-01

496

Wireless sensor networks  

Microsoft Academic Search

Advances in commercial IC fabrication technology have made possible the integration of wireless transceivers, CMOS signal processing, and sensing in one integrated circuit package. Combination with actuation is also possible. This amounts to a low-cost means to link communications and computer networks to the physical world, and may have profound consequences in such diverse areas as security, process control, planetary

G. J. Pottie

1998-01-01

497

Research Networks - Applied Research  

Cancer.gov

Research networks such as those listed below have established new approaches to data collection, sharing, and analysis. These approaches allow investigators to deepen their understanding of barriers to cancer prevention, early detection, treatment, and healthcare services in community settings and how these barriers affect quality of life and other cancer outcomes.

498

Noisy Road Network Matching  

Microsoft Academic Search

Let N and M be two road networks represented in vector form and covering rectangular areas R and R0, respectively, not necessarily parallel to each other, but with R0 ‰ R. We assume that N and M use difierent coordinate systems at (possibly) difierent, but known scales. Let B and A denote sets of \\\\prominent\\

Yago Diez; Mario A. Lopez; Joan Antoni Sellarès

2008-01-01

499

Babylonian Resistor Networks  

ERIC Educational Resources Information Center

The ancient Babylonians had an iterative technique for numerically approximating the values of square roots. Their method can be physically implemented using series and parallel resistor networks. A recursive formula for the equivalent resistance R[subscript eq] is developed and converted into a nonrecursive solution for circuits using…

Mungan, Carl E.; Lipscombe, Trevor C.

2012-01-01

500

Home network security  

Microsoft Academic Search

Telcordia has submitted proposals to standards bodies for the specification of two easily implemented security services, SSL\\/TLS and IPSec, that can provide a substantial defense for the home. We show how these services would be implemented in both user devices on the home network and in the residential gateway, and describe the cooperation that would be necessary to effect home

S. G. Ungar

2002-01-01